Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/30/14
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1045 PM EDT SUN JUN 29 2014
.SYNOPSIS...
UPPER RIDGE WILL CONTINUE OVER THE AREA THROUGH TUESDAY. A
DISTURBANCE OFF THE SOUTHEAST COAST WILL MEANDER OFF THE COAST.
ISOLATED TO WIDELY SCATTERED SHOWERS AND THUNDERSTORMS ARE
POSSIBLE THROUGH TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
THROUGH MIDNIGHT...ACTIVITY FROM THE UPSTATE AND GEORGIA HAS MOVED
INTO THE PIEDMONT AND CENTRAL SAVANNAH RIVER AREA. HOWEVER...IS
HAS WEAKENED QUITE A BIT. MODELS INDICATE THIS ACTIVITY ASSOCIATED
WITH A WEAKENING S/W MOVING EASTWARD ACROSS THE CWA TONIGHT.
EXPECT THE ACTIVITY TO GRADUALLY DIMINISH AFTER MIDNIGHT. FROM
MIDNIGHT TOWARD MORNING...THE UPPER LEVEL RIDGE OVER THE AREA WILL
CONTINUE TO FLATTEN. WEAK LOW WILL REMAIN OFF THE SOUTHEASTERN
COAST. ALTHOUGH PWAT VALUES WILL REMAIN IN EXCESS OF 1.7 INCHES
OVERNIGHT...INSTABILITY WILL REMAIN WEAK AND MODELS INDICATE SOME
SUBSIDENCE ACROSS THE EASTERN MIDLANDS WITH RIDING ALOFT AND LOW
ALONG THE SOUTHEAST COAST. WILL CONTINUE WITH HIGHEST POPS OVER
THE CSRA AND WESTERN MIDLANDS BEFORE MIDNIGHT WITH LITTLE CHANCE
OF RAIN AFTER MIDNIGHT. OVERNIGHT LOWS WILL BE IN THE UPPER 60S TO
LOWER 70S.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY/...
A SURFACE LOW WILL MEANDER OFF THE SOUTHEAST COAST AND DRIFT
SLOWLY TOWARD FLORIDA THROUGH TUESDAY. RIDGING ALOFT WILL
CONTINUE OVER THE FORECAST AREA. WHILE MOISTURE REMAINS
PLENTIFUL...THERE WILL BE A GENERAL LACK OF FORCING FOR
CONVECTION. THUS AM TRENDING POPS DOWN IN THE SHORT
TERM...EXPECTING ONLY WIDELY SCATTERED SHOWERS OR STORMS MAINLY
LATE AFTERNOON AND EARLY EVENING. TEMPS NEAR GUIDANCE WITH AFTERNOON
HIGHS IN THE LOWER TO MIDDLE 90S AND OVERNIGHT LOWS IN THE LOWER
70S.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
THE FORECAST FOR THE LONG TERM DEPENDS ON THE EVOLUTION OF THE
SYSTEM OFF THE SOUTHEAST COAST. CURRENT THINKING IS THAT THIS
SYSTEM WILL STAY OFF THE COAST AND NOT HAVE MUCH IMPACT ON THE
FORECAST AREA. THE NHC SAYS IT IS LIKELY THAT THE SYSTEM WILL FOR
INTO A TROPICAL DEPRESSION BY MID WEEK AS THE ENVIRONMENTAL
CONDITIONS BECOME MORE FAVORABLE. CONFIDENCE FOR PRECIPITATION IS
ON THE LOW SIDE OF MEDIUM...FOR NOW WILL CONTINUE NORMAL TO
SLIGHTLY ABOVE NORMAL TEMPS WITH PRECIPITATION CHANCES AROUND 20
PERCENT AT NIGHT AND 30 PERCENT DURING THE DAY.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
HIGH PRESSURE ACROSS THE TAF SITES BOTH SURFACE AND ALOFT WILL KEEP
WINDS LIGHT AND VARIABLE THROUGH THE PERIOD.
EVENING CONVECTION CONTINUES TO DIMINISH...SO WILL NOT INCLUDE IN
TAFS. LOW LEVELS REMAIN MOIST SO IFR/MVFR FOG/STRATUS IS POSSIBLE
AFTER 08Z...ESPECIALLY AT AGS/DNL/OGB. BASED ON LATEST RUC MODEL AND
PERSISTENCE...WILL INDICATE MVFR CONDITIONS AFTER 08Z. ANY
FOG/STRATUS THAT DEVELOP SHOULD LIFT/DISSIPATE IN THE 13Z-17Z
TIME-FRAME...WITH MAINLY VFR FOR MONDAY AFTERNOON. SCATTERED
CONVECTION POSSIBLE MONDAY AFTERNOON...ALTHOUGH THE BEST CHANCE WILL
BE WEST OF THE TAF SITES WHERE MOISTURE AND INSTABILITY WILL BE
GREATER.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE IN LATE
NIGHT/EARLY MORNING STRATUS/FOG AS WELL AS SCATTERED
AFTERNOON/EVENING THUNDERSTORMS THROUGH FRIDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
77
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
949 PM CDT SUN JUN 29 2014
.DISCUSSION...
801 PM CDT
ALL ATTENTION THIS EVENING IS FOCUSED ON THE RATHER IMPRESSIVE
ONGOING CONVECTION ACROSS IOWA.
IT APPEARS THAT ALTHOUGH LARGE SCALE FORCING FOR ASCENT IS RATHER
WEAK...THAT THE CONVECTIVE ACTIVITY WILL CONTINUE TO DEVELOP/MAINTAIN
ITSELF ACROSS CENTRAL AND EASTERN SECTIONS OF IOWA THROUGH THIS
EVENING AS THE LOW LEVEL JET INCREASES. THE MAIN CONCERNS FOR MY
AREA IS IF ANY OF THIS ACTIVITY WILL BUILD UPSCALE INTO ANY FORWARD
PROPAGATING SEGMENTS. UNFORTUNATELY CONFIDENCE REMAINS LOW WITH THIS
POSSIBILITY. HOWEVER...IF THIS WERE TO OCCUR...THE CORFIDI FORWARD
PROPAGATING VECTORS SUGGEST THAT THE FORWARD PROPAGATING SEGMENTS
WOULD FAVOR A NEARLY DUE EASTERLY MOVEMENT. THIS WOULD SUGGEST THAT
FAR NORTHERN ILLINOIS WOULD BE THE MOST LIKELY CANDIDATES FOR THIS
ACTIVITY LATER TONIGHT AFTER MIDNIGHT. THE 00 UTC SOUNDING OUT OF
KDVN INDICATES THE PRESENCE OF A STRONGLY UNSTABLE ENVIRONMENT...WITH
JUST OVER 3800 J/KG OF SBCAPE...THANKS TO THE PRESENCE OF VERY STEEP MID
LEVEL LAPSE RATES ASSOCIATED WITH AN EML. ALTHOUGH THIS EML IS
ACTING AS A CAP CURRENTLY...ONCE STORMS EVOLVE EASTWARD...THE DRY
AIR IN THE MID LEVELS SUGGESTS THE POTENTIAL OF OUTFLOW DOMINATE
STORMS...WHICH WOULD CERTAINLY FAVOR THE POTENTIAL FOR FORWARD
PROPAGATING CONVECTIVE ELEMENTS CAPABLE OF PRODUCING DAMAGING
WINDS AND POSSIBLY SOME LARGE HAIL...ESPECIALLY CONSIDERING THE
PRESENCE OF NEARLY 50 KT OF MID LEVEL WESTERLY FLOW.
THE MAIN WILDCARD TO THIS POSSIBILITY OF CONVECTION MOVING ACROSS
NORTHERN ILLINOIS TONIGHT WILL BE IF AND HOW THE CONVECTIVE ACTIVITY
EXPECTED FARTHER SOUTH ACROSS MISSOURI TONIGHT AFFECTS THE MOISTURE
TRANSPORT INTO NORTHERN ILLINOIS. MODEL GUIDANCE DOES SUGGEST THAT
THE PORTIONS OF MISSOURI WILL RESIDE ALONG THE NOSE OF THE LOW LEVEL
JET TONIGHT...AND THIS COMBINED WITH THE PRESENCE OF A CONVECTIVELY
ENHANCED SHORT WAVE ACROSS EASTERN KANSAS...COULD FAVOR CONVECTIVE
ACTIVITY TO THRIVE IN MISSOURI TONIGHT. IN RETURN...THIS COULD ACT
TO ROB THE MOISTURE TRANSPORT FROM STORMS MOVING INTO NORTHERN
ILLINOIS...WHICH COULD CAUSE THEM TO WEAKEN AS THEY SHIFT EASTWARD
OVERNIGHT.
GIVEN THE UNCERTAINTY IN WHICH SCENARIO WILL PLAY OUT...I HAVE CHOSEN
TO NOT MAKE ANY BIG CHANGES TO THE GOING POPS AT THIS TIME. OUR
CURRENT FORECAST PLACES THE HIGHEST CHANCES ACROSS NORTH CENTRAL
ILLINOIS FROM 6 TO 9 UTC TONIGHT...WHICH STILL SEEMS
REASONABLE.
THE SEVERE WEATHER THREAT CONTINUES TO LOOK THE GREATEST FOR LATE
MONDAY AFTERNOON AND EVENING.
KJB
//PREV DISCUSSION...
204 PM CDT
TONIGHT...
LINGERING STRATUS CLOUDS FINALLY BURNED OFF LATE THIS MORNING...WITH
SOME SCATTERED CUMULUS DEVELOPING EARLY THIS AFTN. VISIBLE IMAGERY
INDICATES SOME OF THE CU FIELD WAS BECOMING AGITATED AND TRYING TO
BUILD SOUTH OF I-80 THIS AFTN...WHICH WAS THE REGION WHERE BETTER
MOISTURE WAS AVAILABLE AS DEW POINTS LINGERED ARND 70 TO LOW 70S.
THE STRONGER WAVE WAS STILL WELL WEST OF THE CWFA INTO
CENTRAL/WESTERN IOWA...WITH THE FOCUS FOR STRONG/SEVERE STORMS THIS
AFTN/EVE WILL RESIDE. FURTHER EAST ACROSS NORTHERN IL/NORTHWEST
IN...THE ATMOSPHERE WILL STEADILY BECOME MORE UNSTABLE. SOUNDINGS
CONTINUE TO INDICATE A WEAK WARM LAYER ALOFT...HOWEVER IT HAS BEEN
SLIGHTLY COOLER THAN WAS EXPECTED. WHICH WILL LIKELY KEEP TEMPS
SLIGHTLY COOLER THIS AFTN...ALTHOUGH A FEW POINTS ALONG AND SOUTH OF
LASALLE TO VALPARAISO COULD STILL TAG 90 THIS AFTN. OTHERWISE TEMPS
SHUD TOP OUT IN THE MID TO PERHAPS UPR 80S.
THE STORY FOR TONIGHT WILL BE SHOW OR NO-SHOW IN REGARDS TO
CONVECTION. THEN IN WHAT CAPACITY WILL IT ARRIVE ACROSS A PORTION OF
OUR CWFA TONIGHT/EARLY MON. LATEST RAP SOUNDINGS WOULD SUGGEST WE
ARE SITTING ON ABOUT 2K J/KG OF CAPE...UNFORTUNATELY A WARM LAYER
ALOFT WILL LIKELY KEEP CONVECTIVE COVERAGE TO A MINIMA THRU AT LEAST
23Z. UPSTREAM THE SPC MESOANALYSIS INDICATES THE INHIBITION OVER
CENTRAL IA SHUD BEGIN TO DISSOLVE BY 20-21Z...AND EXPECT AN UPTICK
IN CONVECTIVE GROWTH THERE. LOCAL ARW8KM SOLUTION HAS A SIMILAR WARM
LAYER ALOFT...WHICH WILL LIKELY ACT AS A CAP AND COULD LINGER TO
ARND 00Z MON TO POSSIBLY 04Z.
UTILIZING THE BUNKER STORM MOTION...IT APPEARS THAT IF CONVECTION
CAN DEVELOP UPSTREAM IT WOULD SLIDE EAST TOWARDS THE CENTRAL CWFA
THEN TURN SOUTHEAST CLIPPING THE SOUTHERN CWFA. BUT THE QUESTION
REMAINS WILL CONVECTION BE ABLE TO MAINTAIN ITSELF INTO THE CWFA
TONIGHT...AND WITH THE STRENGTHENING PUSH OF WARM AIR ALOFT THIS
LOOKS TO BE CHALLENGING.
EXPECT TEMPS TO REMAIN MILD WITH LOWS IN THE LOW 70S.
MONDAY...
THIS CONTINUES TO BE THE DAY OF GREATEST CONCERN FOR STRONG/SEVERE
STORMS. THE TIMING FOR CONVECTIVE DEVELOPMENT LOOKS TO BE FOCUSED IN
THE AFTN/EVE TIMEFRAME. THE DAY SHUD START OFF WITH SOME SCT SHOWERS
POSSIBLY AN ISOLATED STORM OR TWO. PROFILES INDICATE STEEPENING
LAPSE RATES BY EARLY AFTN...HOWEVER THERE IS STILL A SIZABLE PUSH
OF WARM AIR ALOFT THAT COULD KEEP THINGS CAPPED YET AGAIN THRU
21-22Z MON. GUIDANCE CONTINUES TO SUGGEST THE WAVE OVER IOWA ALONG
THE LEADING EDGE OF A MID-LVL TROUGH/VORT TO BE THE FOCAL POINT.
THIS FEATURE IS PROGGED TO ARRIVE OVER THE FORECAST AREA AFT
21Z...SO THE TIMING OF LATE AFTN/EVE FOR GREATEST CONVECTIVE GROWTH
AND COVERAGE REMAINS IN PLACE. STORM MOTION MON EVE LOOKS TO BE
PUSHING EAST THEN BEGIN TURNING SOUTHEAST. AT THIS TIME SPC HAS THE
ENTIRE AREA OUTLOOKED FOR SLIGHT RISK...WITH THE GREATEST HAZARDS
BEING LARGE HAIL AND DAMAGING WINDS.
TEMPS MON WILL HINGE UPON THE MORNING CLOUD COVERAGE AND HOW QUICKLY
THAT CAN ERODE. AT THIS TIME IT APPEARS TEMPS SHUD PUSH INTO THE
MID/UPR 80S WITH DEW PTS IN THE LOW 70S. THE COMBINATION WILL CREATE
HEAT INDEX VALUES IN THE MID/UPR 90S.
TUESDAY THROUGH THURSDAY...
DRY SLOT QUICKLY ARRIVES BEHIND THE VORT PASSAGE TUE...WHICH SHUD
ALLOW MUCH OF TUE TO BE DRY. LLVL FLOW WILL REMAIN SOUTHWESTERLY
WITH A MORE ROBUST MID-LVL TROUGH JUST UPSTREAM ACROSS THE NORTHERN
PLAINS THAT WILL ARRIVE ACROSS THE REGION WED. ANOTHER LOBE OF
VORTICITY IS PROGGED TO PIVOT OVERHEAD WED MORNING...AND WILL BRING
ANOTHER CHC FOR PRECIP. GIVEN THE LACK OF STRONG INSTABILITY...IT
LOOKS LIKE THIS WILL BE GENERAL SHOWERS. FLOW THEN TURNS
NORTHWESTERLY WITH MUCH COOLER AIR FILTERING INTO THE CWFA. TUE
HIGHS WILL LIKELY STILL TAG THE 80S...WITH TEMPS STRUGGLING TO WARM
BEYOND THE LOW/MID 70S WED/THUR. BROAD SFC RIDGE THEN QUICKLY BUILDS
IN WED NGT/THUR...WITH PLEASANT AND LESS HUMID CONDS DEVELOPING.
CONFIDENCE...HIGH.
FRIDAY THROUGH SUNDAY...
ENSEMBLES CONTINUE TO SUGGEST THAT THE PATTERN MAY BE ADJUSTING FOR
THE END OF THE WEEK/WEEKEND WITH A RIDGE BUILDING INTO THE CANADIAN
ROCKIES...WHICH WOULD ALLOW A DOWNSTREAM TROUGH ACROSS THE GREAT
LAKES/NORTHEAST CONUS. IN CONCERT WITH THE RIDGE OUT WEST...THERMAL
TEMPS ARE PROGGED TO SOAR WELL ABOVE NORMAL IN THE WEST AS WELL.
THIS WILL LIKELY AID IN MORE SEASONAL TEMPS FOR THE OUR FORECAST
AREA WITH TEMPS GENERALLY IN THE 70S TO POSSIBLY MID 80S. WHILE IT
LOOKS LIKE A DRY WEEKEND IS IN STORE FOR THE CWFA...IT IS POSSIBLE A
WEAK WAVE COULD SLIDE SOUTHEAST TOWARDS THE REGION AND GENERATE SOME
LOW CHC POPS.
CONFIDENCE...HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 03Z...
* LIKELIHOOD FOR SHRA LATE TONIGHT AND POSSIBLE TSRA.
* MVFR CIGS LIKELY DEVELOPING THROUGH TONIGHT AND PERSISTING
MONDAY MORNING.
* NEAR DUE SOUTHERLY GUSTY WINDS ON MONDAY.
* STRONG GUSTY T-STORMS MONDAY EVENING.
//DISCUSSION...UPDATED 00Z...
THE MAIN IMPACT DURING THE TAF PERIOD WILL LIKELY BE TSRA LATE
MONDAY AFTERNOON AND ESPECIALLY EVENING...HOWEVER SEVERAL THINGS
OF NOTE THROUGHOUT THE NEXT 24-30 HOURS. VERY MOIST LOW-LEVEL AIR
CONTINUES TO FEED NORTHWARD ACROSS THE REGION THIS EVENING. WITHIN
THAT MOIST AIR...PATCHES OF MVFR CIGS HAVE DEVELOPED ACROSS
CENTRAL IL AND FEEL SOME OF THIS COULD GET ADVECTED OR DEVELOP
UPSTREAM ACROSS NORTHERN IL LATE TONIGHT AND PERSIST INTO MONDAY
MORNING. THE 00Z DVN WEATHER BALLOON DATA DOES INDICATE A CAP
CONTINUING WHICH SHOULD PREVENT ANY STORM DEVELOPMENT THIS EVE.
OVERNIGHT THOUGH...STORMS ACROSS IA AS OF 00Z SHOULD EVOLVE
EASTWARD AND FEED ON UNSTABLE AIR ALOFT. THESE WILL LIKELY REACH
THE ROCKFORD AREA NEAR OR SHORTLY AFTER 06Z-07Z. IT IS CHALLENGING
TO SAY WHAT COVERAGE WILL BE...AND THAT WILL BE A DETERMINANT FOR
HOW MUCH IF ANY STORMS CAN REACH EASTWARD TO THE CHICAGO
TERMINALS. FOR THAT REASON...CONTINUING VICINITY MENTION.
MONDAY WILL SEE EARLY MORNING CLOUDS LIFT AND LIKELY SCATTER WITH
GUSTY SOUTHERLY WINDS AS ANOMALOUSLY DEEP LOW PRESSURE FOR
SUMMERTIME MOVES EAST FROM THE CENTRAL PLAINS. IN
RESPONSE...ROBUST THUNDERSTORM DEVELOPMENT IS EXPECTED ACROSS THE
EASTERN HALF OF IA INTO SOUTHERN WI AND NORTHWEST IL DURING MID
TO LATE AFTERNOON ON MONDAY. CONFIDENCE IS HIGH IN THIS GIVEN THE
WEATHER PATTERN...THOUGH TIMING COULD VARY BY A COUPLE/FEW HOURS.
THESE STORMS SHOULD TRACK EAST PRESENTING A SEVERE WEATHER
THREAT...ESPECIALLY VERY GUSTY WINDS AS THEY MOVE ACROSS THE
CHICAGOLAND AREA MONDAY EVE.
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* HIGH IN WINDS.
* LOW IN WHETHER TSRA REACHES AIRFIELDS LATE TONIGHT.
* MEDIUM IN MVFR CIGS DEVELOPING LATE TONIGHT/MONDAY MORNING.
* HIGH IN TSRA OCCURRING MONDAY EVENING. MEDIUM IN TIMING.
//OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z...
TUESDAY...VFR.
WEDNESDAY...SLIGHT CHANCE OF SHRA AND MVFR.
THURSDAY-SATURDAY...VFR LIKELY.
MTF
&&
.MARINE...
212 PM CDT
UNSEASONABLY STRONG LOW PRESSURE SYSTEM LIES OVER MANITOBA THIS
AFTERNOON WITH MODERATE SOUTHERLY FLOW ACROSS LAKE MICHIGAN.
STABLE CONDITIONS OVER THE LAKE ARE HELPING TO KEEP THE WINDS IN
CHECK TO SOME DEGREE...BUT SOME SHIPS HAVE REPORTED WINDS TO
AROUND 30 KT SO FAR TODAY. THE GRADIENT WILL BE MAINTAINED THROUGH
TUESDAY WITH THE MODERATE WINDS CONTINUING THROUGH THIS PERIOD.
WINDS WILL BE CLOSE TO SMALL CRAFT ADVISORY CRITERIA BOTH ON
MONDAY AND AGAIN TUESDAY. ALSO...DEWPOINTS INTO THE 60S HAVE BEEN
TRANSPORTED INTO THE GREAT LAKES REGION AND CONTINUES TO RESULT IN
FOG ESPECIALLY ACROSS THE NORTH HALF OF THE LAKE. THERE IS NO
CLEAR REASON FOR THE FOG TO DISSIPATE UNTIL LATER TUESDAY INTO
WEDNESDAY WHEN A COLD FRONT SWEEPS ACROSS THE LAKE. WILL EXTEND
THE FOG ADVISORY FOR NORTHERN LAKE MICHIGAN INTO MONDAY
AFTERNOON...BUT IT MAY BE NEEDED FOR ANOTHER 24 HOURS OR SO BEYOND
THAT EVEN.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ868 UNTIL 9 PM MONDAY.
&&
$$
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AREA FORECAST DISCUSSION...UPDATED
NWS CHICAGO/ROMEOVILLE IL
807 PM CDT SUN JUN 29 2014
.DISCUSSION...
801 PM CDT
ALL ATTENTION THIS EVENING IS FOCUSED ON THE RATHER IMPRESSIVE
ONGOING CONVECTION ACROSS IOWA.
IT APPEARS THAT ALTHOUGH LARGE SCALE FORCING FOR ASCENT IS RATHER
WEAK...THAT THE CONVECTIVE ACTIVITY WILL CONTINUE TO DEVELOP/MAINTAIN
ITSELF ACROSS CENTRAL AND EASTERN SECTIONS OF IOWA THROUGH THIS
EVENING AS THE LOW LEVEL JET INCREASES. THE MAIN CONCERNS FOR MY
AREA IS IF ANY OF THIS ACTIVITY WILL BUILD UPSCALE INTO ANY FORWARD
PROPAGATING SEGMENTS. UNFORTUNATELY CONFIDENCE REMAINS LOW WITH THIS
POSSIBILITY. HOWEVER...IF THIS WERE TO OCCUR...THE CORFIDI FORWARD
PROPAGATING VECTORS SUGGEST THAT THE FORWARD PROPAGATING SEGMENTS
WOULD FAVOR A NEARLY DUE EASTERLY MOVEMENT. THIS WOULD SUGGEST THAT
FAR NORTHERN ILLINOIS WOULD BE THE MOST LIKELY CANDIDATES FOR THIS
ACTIVITY LATER TONIGHT AFTER MIDNIGHT. THE 00 UTC SOUNDING OUT OF
KDVN INDICATES THE PRESENCE OF A STRONGLY UNSTABLE ENVIRONMENT...WITH
JUST OVER 3800 J/KG OF SBCAPE...THANKS TO THE PRESENCE OF VERY STEEP MID
LEVEL LAPSE RATES ASSOCIATED WITH AN EML. ALTHOUGH THIS EML IS
ACTING AS A CAP CURRENTLY...ONCE STORMS EVOLVE EASTWARD...THE DRY
AIR IN THE MID LEVELS SUGGESTS THE POTENTIAL OF OUTFLOW DOMINATE
STORMS...WHICH WOULD CERTAINLY FAVOR THE POTENTIAL FOR FORWARD
PROPAGATING CONVECTIVE ELEMENTS CAPABLE OF PRODUCING DAMAGING
WINDS AND POSSIBLY SOME LARGE HAIL...ESPECIALLY CONSIDERING THE
PRESENCE OF NEARLY 50 KT OF MID LEVEL WESTERLY FLOW.
THE MAIN WILDCARD TO THIS POSSIBILITY OF CONVECTION MOVING ACROSS
NORTHERN ILLINOIS TONIGHT WILL BE IF AND HOW THE CONVECTIVE ACTIVITY
EXPECTED FARTHER SOUTH ACROSS MISSOURI TONIGHT AFFECTS THE MOISTURE
TRANSPORT INTO NORTHERN ILLINOIS. MODEL GUIDANCE DOES SUGGEST THAT
THE PORTIONS OF MISSOURI WILL RESIDE ALONG THE NOSE OF THE LOW LEVEL
JET TONIGHT...AND THIS COMBINED WITH THE PRESENCE OF A CONVECTIVELY
ENHANCED SHORT WAVE ACROSS EASTERN KANSAS...COULD FAVOR CONVECTIVE
ACTIVITY TO THRIVE IN MISSOURI TONIGHT. IN RETURN...THIS COULD ACT
TO ROB THE MOISTURE TRANSPORT FROM STORMS MOVING INTO NORTHERN
ILLINOIS...WHICH COULD CAUSE THEM TO WEAKEN AS THEY SHIFT EASTWARD
OVERNIGHT.
GIVEN THE UNCERTAINTY IN WHICH SCENARIO WILL PLAY OUT...I HAVE CHOSEN
TO NOT MAKE ANY BIG CHANGES TO THE GOING POPS AT THIS TIME. OUR
CURRENT FORECAST PLACES THE HIGHEST CHANCES ACROSS NORTH CENTRAL
ILLINOIS FROM 6 TO 9 UTC TONIGHT...WHICH STILL SEEMS
REASONABLE.
THE SEVERE WEATHER THREAT CONTINUES TO LOOK THE GREATEST FOR LATE
MONDAY AFTERNOON AND EVENING.
KJB
&&
.PREV DISCUSSION...
204 PM CDT
TONIGHT...
LINGERING STRATUS CLOUDS FINALLY BURNED OFF LATE THIS MORNING...WITH
SOME SCATTERED CUMULUS DEVELOPING EARLY THIS AFTN. VISIBLE IMAGERY
INDICATES SOME OF THE CU FIELD WAS BECOMING AGITATED AND TRYING TO
BUILD SOUTH OF I-80 THIS AFTN...WHICH WAS THE REGION WHERE BETTER
MOISTURE WAS AVAILABLE AS DEW POINTS LINGERED ARND 70 TO LOW 70S.
THE STRONGER WAVE WAS STILL WELL WEST OF THE CWFA INTO
CENTRAL/WESTERN IOWA...WITH THE FOCUS FOR STRONG/SEVERE STORMS THIS
AFTN/EVE WILL RESIDE. FURTHER EAST ACROSS NORTHERN IL/NORTHWEST
IN...THE ATMOSPHERE WILL STEADILY BECOME MORE UNSTABLE. SOUNDINGS
CONTINUE TO INDICATE A WEAK WARM LAYER ALOFT...HOWEVER IT HAS BEEN
SLIGHTLY COOLER THAN WAS EXPECTED. WHICH WILL LIKELY KEEP TEMPS
SLIGHTLY COOLER THIS AFTN...ALTHOUGH A FEW POINTS ALONG AND SOUTH OF
LASALLE TO VALPARAISO COULD STILL TAG 90 THIS AFTN. OTHERWISE TEMPS
SHUD TOP OUT IN THE MID TO PERHAPS UPR 80S.
THE STORY FOR TONIGHT WILL BE SHOW OR NO-SHOW IN REGARDS TO
CONVECTION. THEN IN WHAT CAPACITY WILL IT ARRIVE ACROSS A PORTION OF
OUR CWFA TONIGHT/EARLY MON. LATEST RAP SOUNDINGS WOULD SUGGEST WE
ARE SITTING ON ABOUT 2K J/KG OF CAPE...UNFORTUNATELY A WARM LAYER
ALOFT WILL LIKELY KEEP CONVECTIVE COVERAGE TO A MINIMA THRU AT LEAST
23Z. UPSTREAM THE SPC MESOANALYSIS INDICATES THE INHIBITION OVER
CENTRAL IA SHUD BEGIN TO DISSOLVE BY 20-21Z...AND EXPECT AN UPTICK
IN CONVECTIVE GROWTH THERE. LOCAL ARW8KM SOLUTION HAS A SIMILAR WARM
LAYER ALOFT...WHICH WILL LIKELY ACT AS A CAP AND COULD LINGER TO
ARND 00Z MON TO POSSIBLY 04Z.
UTILIZING THE BUNKER STORM MOTION...IT APPEARS THAT IF CONVECTION
CAN DEVELOP UPSTREAM IT WOULD SLIDE EAST TOWARDS THE CENTRAL CWFA
THEN TURN SOUTHEAST CLIPPING THE SOUTHERN CWFA. BUT THE QUESTION
REMAINS WILL CONVECTION BE ABLE TO MAINTAIN ITSELF INTO THE CWFA
TONIGHT...AND WITH THE STRENGTHENING PUSH OF WARM AIR ALOFT THIS
LOOKS TO BE CHALLENGING.
EXPECT TEMPS TO REMAIN MILD WITH LOWS IN THE LOW 70S.
MONDAY...
THIS CONTINUES TO BE THE DAY OF GREATEST CONCERN FOR STRONG/SEVERE
STORMS. THE TIMING FOR CONVECTIVE DEVELOPMENT LOOKS TO BE FOCUSED IN
THE AFTN/EVE TIMEFRAME. THE DAY SHUD START OFF WITH SOME SCT SHOWERS
POSSIBLY AN ISOLATED STORM OR TWO. PROFILES INDICATE STEEPENING
LAPSE RATES BY EARLY AFTN...HOWEVER THERE IS STILL A SIZABLE PUSH
OF WARM AIR ALOFT THAT COULD KEEP THINGS CAPPED YET AGAIN THRU
21-22Z MON. GUIDANCE CONTINUES TO SUGGEST THE WAVE OVER IOWA ALONG
THE LEADING EDGE OF A MID-LVL TROUGH/VORT TO BE THE FOCAL POINT.
THIS FEATURE IS PROGGED TO ARRIVE OVER THE FORECAST AREA AFT
21Z...SO THE TIMING OF LATE AFTN/EVE FOR GREATEST CONVECTIVE GROWTH
AND COVERAGE REMAINS IN PLACE. STORM MOTION MON EVE LOOKS TO BE
PUSHING EAST THEN BEGIN TURNING SOUTHEAST. AT THIS TIME SPC HAS THE
ENTIRE AREA OUTLOOKED FOR SLIGHT RISK...WITH THE GREATEST HAZARDS
BEING LARGE HAIL AND DAMAGING WINDS.
TEMPS MON WILL HINGE UPON THE MORNING CLOUD COVERAGE AND HOW QUICKLY
THAT CAN ERODE. AT THIS TIME IT APPEARS TEMPS SHUD PUSH INTO THE
MID/UPR 80S WITH DEW PTS IN THE LOW 70S. THE COMBINATION WILL CREATE
HEAT INDEX VALUES IN THE MID/UPR 90S.
TUESDAY THROUGH THURSDAY...
DRY SLOT QUICKLY ARRIVES BEHIND THE VORT PASSAGE TUE...WHICH SHUD
ALLOW MUCH OF TUE TO BE DRY. LLVL FLOW WILL REMAIN SOUTHWESTERLY
WITH A MORE ROBUST MID-LVL TROUGH JUST UPSTREAM ACROSS THE NORTHERN
PLAINS THAT WILL ARRIVE ACROSS THE REGION WED. ANOTHER LOBE OF
VORTICITY IS PROGGED TO PIVOT OVERHEAD WED MORNING...AND WILL BRING
ANOTHER CHC FOR PRECIP. GIVEN THE LACK OF STRONG INSTABILITY...IT
LOOKS LIKE THIS WILL BE GENERAL SHOWERS. FLOW THEN TURNS
NORTHWESTERLY WITH MUCH COOLER AIR FILTERING INTO THE CWFA. TUE
HIGHS WILL LIKELY STILL TAG THE 80S...WITH TEMPS STRUGGLING TO WARM
BEYOND THE LOW/MID 70S WED/THUR. BROAD SFC RIDGE THEN QUICKLY BUILDS
IN WED NGT/THUR...WITH PLEASANT AND LESS HUMID CONDS DEVELOPING.
CONFIDENCE...HIGH.
FRIDAY THROUGH SUNDAY...
ENSEMBLES CONTINUE TO SUGGEST THAT THE PATTERN MAY BE ADJUSTING FOR
THE END OF THE WEEK/WEEKEND WITH A RIDGE BUILDING INTO THE CANADIAN
ROCKIES...WHICH WOULD ALLOW A DOWNSTREAM TROUGH ACROSS THE GREAT
LAKES/NORTHEAST CONUS. IN CONCERT WITH THE RIDGE OUT WEST...THERMAL
TEMPS ARE PROGGED TO SOAR WELL ABOVE NORMAL IN THE WEST AS WELL.
THIS WILL LIKELY AID IN MORE SEASONAL TEMPS FOR THE OUR FORECAST
AREA WITH TEMPS GENERALLY IN THE 70S TO POSSIBLY MID 80S. WHILE IT
LOOKS LIKE A DRY WEEKEND IS IN STORE FOR THE CWFA...IT IS POSSIBLE A
WEAK WAVE COULD SLIDE SOUTHEAST TOWARDS THE REGION AND GENERATE SOME
LOW CHC POPS.
CONFIDENCE...HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* CHANCE FOR TSRA LATE TONIGHT/EARLY MONDAY MORNING.
* MVFR CIGS LIKELY DEVELOPING LATE TONIGHT AND PERSISTING MONDAY
MORNING.
* GUSTY WINDS NEAR DUE SOUTH AT TIMES ON MONDAY.
* STRONG GUSTY T-STORMS MONDAY EVENING.
//DISCUSSION...UPDATED 00Z...
THE MAIN IMPACT DURING THE TAF PERIOD WILL LIKELY BE TSRA LATE
MONDAY AFTERNOON AND ESPECIALLY EVENING...HOWEVER SEVERAL THINGS
OF NOTE THROUGHOUT THE NEXT 24-30 HOURS. VERY MOIST LOW-LEVEL AIR
CONTINUES TO FEED NORTHWARD ACROSS THE REGION THIS EVENING. WITHIN
THAT MOIST AIR...PATCHES OF MVFR CIGS HAVE DEVELOPED ACROSS
CENTRAL IL AND FEEL SOME OF THIS COULD GET ADVECTED OR DEVELOP
UPSTREAM ACROSS NORTHERN IL LATE TONIGHT AND PERSIST INTO MONDAY
MORNING. THE 00Z DVN WEATHER BALLOON DATA DOES INDICATE A CAP
CONTINUING WHICH SHOULD PREVENT ANY STORM DEVELOPMENT THIS EVE.
OVERNIGHT THOUGH...STORMS ACROSS IA AS OF 00Z SHOULD EVOLVE
EASTWARD AND FEED ON UNSTABLE AIR ALOFT. THESE WILL LIKELY REACH
THE ROCKFORD AREA NEAR OR SHORTLY AFTER 06Z-07Z. IT IS CHALLENGING
TO SAY WHAT COVERAGE WILL BE...AND THAT WILL BE A DETERMINANT FOR
HOW MUCH IF ANY STORMS CAN REACH EASTWARD TO THE CHICAGO
TERMINALS. FOR THAT REASON...CONTINUING VICINITY MENTION.
MONDAY WILL SEE EARLY MORNING CLOUDS LIFT AND LIKELY SCATTER WITH
GUSTY SOUTHERLY WINDS AS ANOMALOUSLY DEEP LOW PRESSURE FOR
SUMMERTIME MOVES EAST FROM THE CENTRAL PLAINS. IN
RESPONSE...ROBUST THUNDERSTORM DEVELOPMENT IS EXPECTED ACROSS THE
EASTERN HALF OF IA INTO SOUTHERN WI AND NORTHWEST IL DURING MID
TO LATE AFTERNOON ON MONDAY. CONFIDENCE IS HIGH IN THIS GIVEN THE
WEATHER PATTERN...THOUGH TIMING COULD VARY BY A COUPLE/FEW HOURS.
THESE STORMS SHOULD TRACK EAST PRESENTING A SEVERE WEATHER
THREAT...ESPECIALLY VERY GUSTY WINDS AS THEY MOVE ACROSS THE
CHICAGOLAND AREA MONDAY EVE.
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* HIGH IN WINDS.
* LOW IN WEATHER TSRA REACHES AIRFIELDS LATE TONIGHT.
* MEDIUM IN MVFR CIGS DEVELOPING LATE TONIGHT/MONDAY MORNING.
* HIGH IN TSRA OCCURRING MONDAY EVENING. MEDIUM IN TIMING.
//OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z...
TUESDAY...VFR.
WEDNESDAY...SLIGHT CHANCE OF SHRA AND MVFR.
THURSDAY-SATURDAY...VFR LIKELY.
MTF
&&
.MARINE...
212 PM CDT
UNSEASONABLY STRONG LOW PRESSURE SYSTEM LIES OVER MANITOBA THIS
AFTERNOON WITH MODERATE SOUTHERLY FLOW ACROSS LAKE MICHIGAN.
STABLE CONDITIONS OVER THE LAKE ARE HELPING TO KEEP THE WINDS IN
CHECK TO SOME DEGREE...BUT SOME SHIPS HAVE REPORTED WINDS TO
AROUND 30 KT SO FAR TODAY. THE GRADIENT WILL BE MAINTAINED THROUGH
TUESDAY WITH THE MODERATE WINDS CONTINUING THROUGH THIS PERIOD.
WINDS WILL BE CLOSE TO SMALL CRAFT ADVISORY CRITERIA BOTH ON
MONDAY AND AGAIN TUESDAY. ALSO...DEWPOINTS INTO THE 60S HAVE BEEN
TRANSPORTED INTO THE GREAT LAKES REGION AND CONTINUES TO RESULT IN
FOG ESPECIALLY ACROSS THE NORTH HALF OF THE LAKE. THERE IS NO
CLEAR REASON FOR THE FOG TO DISSIPATE UNTIL LATER TUESDAY INTO
WEDNESDAY WHEN A COLD FRONT SWEEPS ACROSS THE LAKE. WILL EXTEND
THE FOG ADVISORY FOR NORTHERN LAKE MICHIGAN INTO MONDAY
AFTERNOON...BUT IT MAY BE NEEDED FOR ANOTHER 24 HOURS OR SO BEYOND
THAT EVEN.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ868 UNTIL 9 PM MONDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
655 PM CDT SUN JUN 29 2014
.DISCUSSION...
204 PM CDT
TONIGHT...
LINGERING STRATUS CLOUDS FINALLY BURNED OFF LATE THIS MORNING...WITH
SOME SCATTERED CUMULUS DEVELOPING EARLY THIS AFTN. VISIBLE IMAGERY
INDICATES SOME OF THE CU FIELD WAS BECOMING AGITATED AND TRYING TO
BUILD SOUTH OF I-80 THIS AFTN...WHICH WAS THE REGION WHERE BETTER
MOISTURE WAS AVAILABLE AS DEW POINTS LINGERED ARND 70 TO LOW 70S.
THE STRONGER WAVE WAS STILL WELL WEST OF THE CWFA INTO
CENTRAL/WESTERN IOWA...WITH THE FOCUS FOR STRONG/SEVERE STORMS THIS
AFTN/EVE WILL RESIDE. FURTHER EAST ACROSS NORTHERN IL/NORTHWEST
IN...THE ATMOSPHERE WILL STEADILY BECOME MORE UNSTABLE. SOUNDINGS
CONTINUE TO INDICATE A WEAK WARM LAYER ALOFT...HOWEVER IT HAS BEEN
SLIGHTLY COOLER THAN WAS EXPECTED. WHICH WILL LIKELY KEEP TEMPS
SLIGHTLY COOLER THIS AFTN...ALTHOUGH A FEW POINTS ALONG AND SOUTH OF
LASALLE TO VALPARAISO COULD STILL TAG 90 THIS AFTN. OTHERWISE TEMPS
SHUD TOP OUT IN THE MID TO PERHAPS UPR 80S.
THE STORY FOR TONIGHT WILL BE SHOW OR NO-SHOW IN REGARDS TO
CONVECTION. THEN IN WHAT CAPACITY WILL IT ARRIVE ACROSS A PORTION OF
OUR CWFA TONIGHT/EARLY MON. LATEST RAP SOUNDINGS WOULD SUGGEST WE
ARE SITTING ON ABOUT 2K J/KG OF CAPE...UNFORTUNATELY A WARM LAYER
ALOFT WILL LIKELY KEEP CONVECTIVE COVERAGE TO A MINIMA THRU AT LEAST
23Z. UPSTREAM THE SPC MESOANALYSIS INDICATES THE INHIBITION OVER
CENTRAL IA SHUD BEGIN TO DISSOLVE BY 20-21Z...AND EXPECT AN UPTICK
IN CONVECTIVE GROWTH THERE. LOCAL ARW8KM SOLUTION HAS A SIMILAR WARM
LAYER ALOFT...WHICH WILL LIKELY ACT AS A CAP AND COULD LINGER TO
ARND 00Z MON TO POSSIBLY 04Z.
UTILIZING THE BUNKER STORM MOTION...IT APPEARS THAT IF CONVECTION
CAN DEVELOP UPSTREAM IT WOULD SLIDE EAST TOWARDS THE CENTRAL CWFA
THEN TURN SOUTHEAST CLIPPING THE SOUTHERN CWFA. BUT THE QUESTION
REMAINS WILL CONVECTION BE ABLE TO MAINTAIN ITSELF INTO THE CWFA
TONIGHT...AND WITH THE STRENGTHENING PUSH OF WARM AIR ALOFT THIS
LOOKS TO BE CHALLENGING.
EXPECT TEMPS TO REMAIN MILD WITH LOWS IN THE LOW 70S.
MONDAY...
THIS CONTINUES TO BE THE DAY OF GREATEST CONCERN FOR STRONG/SEVERE
STORMS. THE TIMING FOR CONVECTIVE DEVELOPMENT LOOKS TO BE FOCUSED IN
THE AFTN/EVE TIMEFRAME. THE DAY SHUD START OFF WITH SOME SCT SHOWERS
POSSIBLY AN ISOLATED STORM OR TWO. PROFILES INDICATE STEEPENING
LAPSE RATES BY EARLY AFTN...HOWEVER THERE IS STILL A SIZABLE PUSH
OF WARM AIR ALOFT THAT COULD KEEP THINGS CAPPED YET AGAIN THRU
21-22Z MON. GUIDANCE CONTINUES TO SUGGEST THE WAVE OVER IOWA ALONG
THE LEADING EDGE OF A MID-LVL TROUGH/VORT TO BE THE FOCAL POINT.
THIS FEATURE IS PROGGED TO ARRIVE OVER THE FORECAST AREA AFT
21Z...SO THE TIMING OF LATE AFTN/EVE FOR GREATEST CONVECTIVE GROWTH
AND COVERAGE REMAINS IN PLACE. STORM MOTION MON EVE LOOKS TO BE
PUSHING EAST THEN BEGIN TURNING SOUTHEAST. AT THIS TIME SPC HAS THE
ENTIRE AREA OUTLOOKED FOR SLIGHT RISK...WITH THE GREATEST HAZARDS
BEING LARGE HAIL AND DAMAGING WINDS.
TEMPS MON WILL HINGE UPON THE MORNING CLOUD COVERAGE AND HOW QUICKLY
THAT CAN ERODE. AT THIS TIME IT APPEARS TEMPS SHUD PUSH INTO THE
MID/UPR 80S WITH DEW PTS IN THE LOW 70S. THE COMBINATION WILL CREATE
HEAT INDEX VALUES IN THE MID/UPR 90S.
TUESDAY THROUGH THURSDAY...
DRY SLOT QUICKLY ARRIVES BEHIND THE VORT PASSAGE TUE...WHICH SHUD
ALLOW MUCH OF TUE TO BE DRY. LLVL FLOW WILL REMAIN SOUTHWESTERLY
WITH A MORE ROBUST MID-LVL TROUGH JUST UPSTREAM ACROSS THE NORTHERN
PLAINS THAT WILL ARRIVE ACROSS THE REGION WED. ANOTHER LOBE OF
VORTICITY IS PROGGED TO PIVOT OVERHEAD WED MORNING...AND WILL BRING
ANOTHER CHC FOR PRECIP. GIVEN THE LACK OF STRONG INSTABILITY...IT
LOOKS LIKE THIS WILL BE GENERAL SHOWERS. FLOW THEN TURNS
NORTHWESTERLY WITH MUCH COOLER AIR FILTERING INTO THE CWFA. TUE
HIGHS WILL LIKELY STILL TAG THE 80S...WITH TEMPS STRUGGLING TO WARM
BEYOND THE LOW/MID 70S WED/THUR. BROAD SFC RIDGE THEN QUICKLY BUILDS
IN WED NGT/THUR...WITH PLEASANT AND LESS HUMID CONDS DEVELOPING.
CONFIDENCE...HIGH.
FRIDAY THROUGH SUNDAY...
ENSEMBLES CONTINUE TO SUGGEST THAT THE PATTERN MAY BE ADJUSTING FOR
THE END OF THE WEEK/WEEKEND WITH A RIDGE BUILDING INTO THE CANADIAN
ROCKIES...WHICH WOULD ALLOW A DOWNSTREAM TROUGH ACROSS THE GREAT
LAKES/NORTHEAST CONUS. IN CONCERT WITH THE RIDGE OUT WEST...THERMAL
TEMPS ARE PROGGED TO SOAR WELL ABOVE NORMAL IN THE WEST AS WELL.
THIS WILL LIKELY AID IN MORE SEASONAL TEMPS FOR THE OUR FORECAST
AREA WITH TEMPS GENERALLY IN THE 70S TO POSSIBLY MID 80S. WHILE IT
LOOKS LIKE A DRY WEEKEND IS IN STORE FOR THE CWFA...IT IS POSSIBLE A
WEAK WAVE COULD SLIDE SOUTHEAST TOWARDS THE REGION AND GENERATE SOME
LOW CHC POPS.
CONFIDENCE...HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* CHANCE FOR TSRA LATE TONIGHT/EARLY MONDAY MORNING.
* MVFR CIGS LIKELY DEVELOPING LATE TONIGHT AND PERSISTING MONDAY
MORNING.
* GUSTY WINDS NEAR DUE SOUTH AT TIMES ON MONDAY.
* STRONG GUSTY T-STORMS MONDAY EVENING.
//DISCUSSION...UPDATED 00Z...
THE MAIN IMPACT DURING THE TAF PERIOD WILL LIKELY BE TSRA LATE
MONDAY AFTERNOON AND ESPECIALLY EVENING...HOWEVER SEVERAL THINGS
OF NOTE THROUGHOUT THE NEXT 24-30 HOURS. VERY MOIST LOW-LEVEL AIR
CONTINUES TO FEED NORTHWARD ACROSS THE REGION THIS EVENING. WITHIN
THAT MOIST AIR...PATCHES OF MVFR CIGS HAVE DEVELOPED ACROSS
CENTRAL IL AND FEEL SOME OF THIS COULD GET ADVECTED OR DEVELOP
UPSTREAM ACROSS NORTHERN IL LATE TONIGHT AND PERSIST INTO MONDAY
MORNING. THE 00Z DVN WEATHER BALLOON DATA DOES INDICATE A CAP
CONTINUING WHICH SHOULD PREVENT ANY STORM DEVELOPMENT THIS EVE.
OVERNIGHT THOUGH...STORMS ACROSS IA AS OF 00Z SHOULD EVOLVE
EASTWARD AND FEED ON UNSTABLE AIR ALOFT. THESE WILL LIKELY REACH
THE ROCKFORD AREA NEAR OR SHORTLY AFTER 06Z-07Z. IT IS CHALLENGING
TO SAY WHAT COVERAGE WILL BE...AND THAT WILL BE A DETERMINANT FOR
HOW MUCH IF ANY STORMS CAN REACH EASTWARD TO THE CHICAGO
TERMINALS. FOR THAT REASON...CONTINUING VICINITY MENTION.
MONDAY WILL SEE EARLY MORNING CLOUDS LIFT AND LIKELY SCATTER WITH
GUSTY SOUTHERLY WINDS AS ANOMALOUSLY DEEP LOW PRESSURE FOR
SUMMERTIME MOVES EAST FROM THE CENTRAL PLAINS. IN
RESPONSE...ROBUST THUNDERSTORM DEVELOPMENT IS EXPECTED ACROSS THE
EASTERN HALF OF IA INTO SOUTHERN WI AND NORTHWEST IL DURING MID
TO LATE AFTERNOON ON MONDAY. CONFIDENCE IS HIGH IN THIS GIVEN THE
WEATHER PATTERN...THOUGH TIMING COULD VARY BY A COUPLE/FEW HOURS.
THESE STORMS SHOULD TRACK EAST PRESENTING A SEVERE WEATHER
THREAT...ESPECIALLY VERY GUSTY WINDS AS THEY MOVE ACROSS THE
CHICAGOLAND AREA MONDAY EVE.
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* HIGH IN WINDS.
* LOW IN WEATHER TSRA REACHES AIRFIELDS LATE TONIGHT.
* MEDIUM IN MVFR CIGS DEVELOPING LATE TONIGHT/MONDAY MORNING.
* HIGH IN TSRA OCCURRING MONDAY EVENING. MEDIUM IN TIMING.
//OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z...
TUESDAY...VFR.
WEDNESDAY...SLIGHT CHANCE OF SHRA AND MVFR.
THURSDAY-SATURDAY...VFR LIKELY.
MTF
&&
.MARINE...
212 PM CDT
UNSEASONABLY STRONG LOW PRESSURE SYSTEM LIES OVER MANITOBA THIS
AFTERNOON WITH MODERATE SOUTHERLY FLOW ACROSS LAKE MICHIGAN.
STABLE CONDITIONS OVER THE LAKE ARE HELPING TO KEEP THE WINDS IN
CHECK TO SOME DEGREE...BUT SOME SHIPS HAVE REPORTED WINDS TO
AROUND 30 KT SO FAR TODAY. THE GRADIENT WILL BE MAINTAINED THROUGH
TUESDAY WITH THE MODERATE WINDS CONTINUING THROUGH THIS PERIOD.
WINDS WILL BE CLOSE TO SMALL CRAFT ADVISORY CRITERIA BOTH ON
MONDAY AND AGAIN TUESDAY. ALSO...DEWPOINTS INTO THE 60S HAVE BEEN
TRANSPORTED INTO THE GREAT LAKES REGION AND CONTINUES TO RESULT IN
FOG ESPECIALLY ACROSS THE NORTH HALF OF THE LAKE. THERE IS NO
CLEAR REASON FOR THE FOG TO DISSIPATE UNTIL LATER TUESDAY INTO
WEDNESDAY WHEN A COLD FRONT SWEEPS ACROSS THE LAKE. WILL EXTEND
THE FOG ADVISORY FOR NORTHERN LAKE MICHIGAN INTO MONDAY
AFTERNOON...BUT IT MAY BE NEEDED FOR ANOTHER 24 HOURS OR SO BEYOND
THAT EVEN.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ868 UNTIL 9 PM MONDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
338 PM CDT SAT JUN 28 2014
.DISCUSSION...
338 PM CDT
WITH NO AIRMASS CHANGE COMING UNTIL MONDAY NIGHT OR TUESDAY...THE
AREA WILL SEE CONTINUED WARM AND HUMID CONDITIONS SUNDAY AND MONDAY
WITH ONGOING CHANCES OF SHOWERS AND THUNDERSTORMS...SOME POSSIBLY
SEVERE LATE MONDAY...FOLLOWED BY COOLER AND DRIER AIR FOR MID WEEK.
A WEAK UPPER DISTURBANCE AND SURFACE WARM FRONT THAT LIFTED THROUGH
THE AREA THIS MORNING BROUGHT A FEW LIGHT SHOWERS AND USHERED IN
WARM HUMID AIR THAT IS SUPPORTING ISOLATED THUNDERSTORMS THIS
AFTERNOON. OVERNIGHT AND TOMORROW MORNING...A STRONGER SHORTWAVE
PASSING ALOFT WILL SUPPORT AN INCREASING CHANCE OF THUNDERSTORMS
DESPITE THE LESS FAVORABLE DIURNAL TIMING. COVERAGE THEN AGAIN
DECREASES AS THIS WAVE EXITS THE AREA TOMORROW AFTERNOON. THE
PATTERN REPEATS ITSELF SUNDAY NIGHT BUT WITH A SOMEWHAT WEAKER WAVE
ALOFT.
BY DAYTIME MONDAY A MORE ACTIVE SCENARIO BEGINS TO EVOLVE. IN
ADDITION TO SHORTWAVE ENERGY SPINNING THROUGH THE UPPER CENTRAL
CONUS TROUGH AND ACROSS THE LOCAL AREA...COPIOUS BOUNDARY LAYER
MOISTURE WILL BE IN PLACE AHEAD OF AN APPROACHING COLD FRONT. BY
LATE MONDAY THE SOUTHERN EDGE OF THE UPPER JET ALSO BEGINS TO WORK
INTO THE AREA...AND WINDS AT BOTH 850 AND 700 MB ARE SIMILARLY
STRONG. SOUTHERLY SURFACE WINDS WILL SUPPORT RELATIVELY BACKED LOW
LEVEL FLOW...CONSIDERABLE MOISTURE TRANSPORT...AND MODERATE DEEP
LAYER SPEED AND DIRECTIONAL SHEAR. THE SHEAR COMPONENT APPEARS TO
BE MOST PRONOUNCED ACROSS NORTHWESTERN ILLINOIS CLOSER TO THE FRONT
AND UNDER THE STRONGER WINDS ALOFT. THE COMBINATION OF ALL THESE
ELEMENTS WILL SUPPORT A SEVERE WEATHER THREAT ACROSS MOST OR ALL OF
THE AREA...AS DEPICTED IN THE LATEST SPC DAY 3 OUTLOOK. IN ADDITION
TO A HAIL THREAT FROM DEEP ORGANIZED CONVECTION...DRY AIR AT MID
LEVELS WILL SUPPORT A DAMAGING WIND THREAT. THE TORNADO THREAT IS
LESS CLEAR AT THIS POINT. THE MOST FAVORABLE PERIOD APPEARS TO BE
LATE MONDAY AFTERNOON OR EVENING...AND A SLOWER TIMING OF THIS
SYSTEM WELL AFTER PEAK HEATING COULD DAMPEN THE ACTIVITY
CONSIDERABLY...AS WOULD A STRONGER CAP AT THE BASE OF THE MIXED
LAYER ALOFT.
AFTER THE COLD FRONT PASSES MONDAY NIGHT...THE AXIS OF THE UPPER
TROUGH THAT IS SUPPORTING THUNDERSTORM CHANCES THROUGH MONDAY DOES
NOT REALLY MOVE EAST OF THE AREA AND ALLOW A BROAD SURFACE HIGH TO
MOVE IN UNTIL THURSDAY. TUESDAY WILL THEREFORE REMAIN WARM BUT NOT
AS HUMID OR UNSETTLED. WEDNESDAY WILL BE A DAY OF TRANSITION BUT
LOOKS TO BE SEVERAL DEGREES COOLER WITH MORE WESTERLY TO
NORTHWESTERLY FLOW. THURSDAY IS SHAPING UP TO BE BOTH COOLER AND
DRIER AS PRONOUNCED NORTHWEST FLOW BECOMES ESTABLISHED AT THE
SURFACE AHEAD OF AN APPROACHING HIGH. THE HIGH THEN APPEARS TO
SETTLE OVERHEAD ON FRIDAY...PROVIDING A DRY AND QUIET INDEPENDENCE
DAY...AT LEAST WEATHERWISE.
AS THE HIGH CONTINUES EAST NEXT WEEKEND...WARMER AND MORE HUMID AIR
AGAIN BEGINS TO MOVE INTO THE AREA. MODELS ARE NOT IN CLOSE
AGREEMENT REGARDING THE APPROACH OF AN UPPER TROUGH...BUT THIS WOULD
LEND SUPPORT TO INCREASED SHOWER AND THUNDERSTORM CHANCES BY NEXT
SATURDAY AND SUNDAY.
LENNING
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* ISOLATED THUNDERSTORMS THIS AFTERNOON/EVENING THEN ANOTHER CHANCE OF
THUNDERSTORMS OVERNIGHT INTO EARLY SUNDAY.
* GUSTY SOUTH WINDS.
BMD
//DISCUSSION...UPDATED 18Z...
LOW PRESSURE IS LIFTING ACROSS THE NORTHERN PLAINS THIS AFTERNOON
WITH SOUTHERLY FLOW IN PLACE ACROSS MUCH OF THE MIDWEST. UNSTABLE
CONDITIONS ARE IN PLACE WITH A REMNANT MCV LIFTING NE ACROSS WEST
CENTRAL ILLINOIS KICKING OFF WIDELY SCATTERED THUNDERSTORMS ACROSS
EAST CENTRAL AND NORTHEAST ILLINOIS. OVERALL THE FORCING REMAINS
FAIRLY WEAK ACROSS THE AREA SO DO NOT ANTICIPATE COVERAGE TO
GREATLY INCREASE. WILL HAVE TO MONITOR NEAR TERM TRENDS TO SEE IF
SOMETHING MAY IMPACT THE TERMINALS DIRECTLY. OTHERWISE...GUSTY SOUTH
WINDS WILL CONTINUE THROUGH THE AFTERNOON AND EVENING.
TONIGHT A NEGATIVELY TILTED TROUGH WILL LIFT FROM THE CENTRAL PLAINS
INTO THE UPPER MISSISSIPPI VALLEY KICKING OFF ADDITIONAL
THUNDERSTORMS TO OUR WEST. THESE STORMS MAY CONGEAL INTO A LINE OF
THUNDERSTORMS THAT WILL BEGIN TO MOVE ACROSS NORTHERN ILLINOIS LATE
OVERNIGHT TOWARDS DAYBREAK SUNDAY. IF THIS OCCURS...TSRA WOULD
EXPECTED TO BE IN A WEAKENING TREND AS IT NEARS THE CHICAGO
TERMINALS. WINDS WILL BE MORE SOUTHWESTERLY DURING THE DAY SUNDAY
WITH GUSTY WINDS CONTINUING.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM-HIGH CONFIDENCE IN WIND DIRECTION/SPEED.
* MEDIUM CONFIDENCE IN ISOLATED TSRA THIS AFTERNOON/EVENING.
* LOW CONFIDENCE IN TSRA OVERNIGHT/EARLY SUNDAY.
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
* SUNDAY NIGHT...CHANCE OF TSRA LATE.
* MONDAY...TSRA LIKELY.
* TUESDAY AND WEDNESDAY...SLIGHT CHANCE SHRA.
* THURSDAY AND FRIDAY...DRY/VFR.
&&
.MARINE...
155 PM CDT
VISIBLE SATELLITE IMAGERY SHOWS SOME AREAS OF FOG...MAINLY CLOSE TO
THE WISCONSIN SHORE...AND GIVEN THE MODEST GRADIENT AND WARMER
TEMPERATURES ADVECTING IN BELIEVE THE THREAT OF WIDESPREAD DENSE FOG
IS FAIRLY LOW. MAINLY SOUTH TO SOUTHEAST WINDS LIKELY TO PERSIST THE
NEXT SEVERAL DAYS BEFORE THE WEAKENING LOW TRACKS EAST TOWARD HUDSON
BAY RESULTING IN A STRENGTHENING PRESSURE GRADIENT LATER SUNDAY
NIGHT INTO MONDAY. WIND SHIFT TO WEST BEHIND THE FRONT THOUGH STABLE
CONDITIONS OVER THE OPEN WATER WILL LIKELY RESULT IN A BACKED
(SOUTHERLY) AND LIGHTER FLOW.
IZZI
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
301 PM CDT Sat Jun 28 2014
.DISCUSSION...
ISSUED 300 PM CDT Sat Jun 28 2014
SHORT TERM...Tonight through Tuesday: Our seemingly daily bout of
diurnal convection will continue into this evening across central
and southeast Illinois. The showers/storms will be most numerous
along the west and east ends of the forecast area in the vicinity
of a couple weak upper waves. However, unlike recent nights, the
threat for precipitation will linger through the night, as a
stronger wave, currently pushing into western MO/IA, crosses the
area. Given the rather weak shear profiles, and diminishing
instability, none of these storms are expected to be severe.
Despite the persistent wetness of many of the models, feel the
bulk of Sunday/Sunday night will wind up dry locally. The
precipitation and/or outflow associated with the MO/IA wave should
be largely east of the forecast area by Sunday morning, with
little in the way of obvious forcing for additional precipitation.
However, storms can certainly not be ruled out due to the fairly
strong instability that is likely to build (around 3000 j/kg
during peak heating). In addition, by late Sunday night we may be
impacted by a MCS or its remnants that develops upstream in the
strong WAA pattern ahead of Monday/Monday night`s cold front.
The precipitation risk for much of Monday is not clear at this
time. There may be some MCS remnants around to start the day, or
most of them may have dissipated before reaching the area. In any
event, dissipated or not, the local airmass is likely to have been
modified by the MCS`s outflow, which could stabilize things for
much of the day. Then, shower/storm chances should increase from
the northwest late in the day into Monday night as a cold front
pushes through the area. Some of the storms with the front could
be severe with fairly strong pre-frontal instability and at least
moderate shear profiles.
Tuesday should be largely dry behind the cold front, although
there may be some lingering precipitation in southeast Illinois.
The passage of the front should signal the start of a fairly
quiet, and somewhat cooler than normal, period across the region.
LONG TERM...Wednesday through Saturday: A least weakly cyclonic
northwest upper level flow will be with us for much of the period,
although it will be be trending more neutral with time. This upper
pattern will also be conducive for high pressure at the surface
for the most part. Have had to add a slight chance of precipitation
to parts of the area for Wednesday as many models now suggest a
stronger wave/trof will pivot around the mean trof in our
vicinity. While this wave will likely be moisture starved, it may
be able to squeeze out a shower or storm. Otherwise, the bulk of
the period is apt to be dry and cooler.
Bak
&&
.AVIATION...
ISSUED 102 PM CDT Sat Jun 28 2014
MVFR ceilings will gradually improve to low VFR at most terminals
over the next couple of hours. The exception will be KBMI, where
slightly lower ceilings will prevail. Subsidence on the back side
of a departing upper-level wave will prevent widespread convection
this afternoon: however, latest satellite imagery and HRRR
guidance suggests widely scattered thunderstorms will develop
across the Illinois River Valley. Have therefore included VCTS at
both KPIA and KSPI through 00z. Any storms that develop this
afternoon will rapidly dissipate by early evening followed by a
period of partly to mostly clear conditions. Next aviation
challenge will be evolution of storms expected to develop across
the Plains this afternoon. Models are offering a wide range of
solutions, with both the HRRR and 4km WRF-NMM indicating storms
crossing the Mississippi River into west-central Illinois in a
weakening state by mid to late evening. Have trended toward this
solution, featuring a period of VCTS at both KPIA and KSPI between
04z and 08z. Think storms will dissipate further east, so will
keep the remaining TAF sites dry with a low VFR ceiling through
the night into Sunday morning.
Barnes
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
259 PM CDT SAT JUN 28 2014
.DISCUSSION...
1047 AM CDT
SMALL BUT WELL DEFINED MCV OVER WEST CENTRAL ILLINOIS IS TWIRLING
VERY SLOWLY EASTWARD. MID LEVEL CLOUDINESS IS PRETTY EXTENSIVE
WITH THIS FEATURE...THOUGH NARROW RIBBON OF SOME CLEARING OVER
EASTERN ILLINOIS HAS ALLOWED FOR SOME BETTER INSOLATION AND
SUBSEQUENT INSTABILITY. ILX AND DVN SOUNDINGS THIS MORNING WERE
VERY MOIST AND MODIFYING FOR CURRENT CONDITIONS ACROSS THE AREA
YIELD MLCAPE VALUES NEARING 2000 J/KG WITH VERY LITTLE CINH.
ALREADY SEEING SOME CONVECTION BEGIN TO POP WITHIN THAT CLEARING
AREA AND SUSPECT THIS TREND WILL CONTINUE WITH COVERAGE INCREASING
OVER MAINLY THE EASTERN 1/3RD OF CWA THROUGH EARLY AFTERNOON. VERY
WEAK VERTICAL SHEAR SHOULD RESULT IN PULSY AND RATHER UNORGANIZED
STORMS.
ANY CLEARING OF THE MID LEVEL DECK UPSTREAM COULD ALSO BE ENOUGH
FOR CONVECTIVE TEMP TO BE REACHED AND SCTD STORMS TO DEVELOP THERE
THIS AFTERNOON AS WELL. OVERALL THINK GOING FORECAST OF ISOLD-SCTD
SHOWERS AND STORMS THIS AFTERNOON ADEQUATELY COVERS EXPECTATIONS.
MORE EXTENSIVE CLOUD COVER IS LOOKING LIKELY TO KEEP TEMPS DOWN A
BIT AND HAVE SHAVED HIGHS TODAY DOWN BY NEARLY A CATEGORY...THOUGH
WITH JUICY DEWPOINTS NEAR 70 IT WILL STILL FEEL PRETTY TOASTY.
IZZI
//PREV DISCUSSION...
355 AM CDT
MAIN FORECAST CHALLENGES ARE THUNDERSTORM CHANCES AND TEMPERATURES
WITH WARM/HUMID CONDITIONS THROUGH MONDAY...THEN GRADUAL COOLING
TUESDAY-WEDNESDAY. HIGH PRESSURE LATE IN THE WEEK SHOULD MAKE FOR
NICE WEATHER FOR THE JULY 4TH HOLIDAY...WITH SIGNS OF WARMER WEATHER
RETURNING OVER THE HOLIDAY WEEKEND.
RATHER INDISTINCT SURFACE WARM FRONT WAS ANALYZED FROM THE UPPER
MIDWEST...SOUTHEAST ACROSS ILLINOIS AND INTO CENTRAL INDIANA EARLY
THIS MORNING. THIS WARM FRONT WILL CONTINUE TO LIFT ACROSS THE
FORECAST AREA THIS MORNING...WITHIN BROAD SOUTHERLY RETURN FLOW IN
LOW LEVELS AHEAD OF LOW PRESSURE OVER THE PLAINS. WARM/MOIST AIR
MASS CHARACTERIZED BY TEMPS IN THE LOW-MID 70S AND DEW POINTS OF
65-70 IS EXPECTED TO DESTABILIZE AFTER SUNRISE...WITH FORECAST
SOUNDINGS FROM 06Z RAP DEPICTING LITTLE/NO CAP AND MLCAPE
APPROACHING 1000 J/KG BY MID/LATE MORNING. SIMILAR TO THE PAST FEW
DAYS...WEAK FLOW ALOFT AND LACK OF STRONG LOW LEVEL CONVERGENT FOCUS
SUGGESTS ONLY ISOLATED TO SCATTERED COVERAGE OF SHOWERS AND
THUNDERSTORMS TODAY. WEAK MID-LEVEL SHORT WAVE IS NOTED OVER THE
REGION THIS MORNING HOWEVER...WITH SOME PERSISTENT WEAK RADAR
RETURNS VICINITY KBMI EVIDENCE OF VORT. PRESENCE OF THIS WEAK WAVE
AND EARLY DESTABILIZATION IS EXPECTED TO RESULT IN ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING BY LATE MORNING WITH
EASTERN PORTIONS OF THE CWA PERHAPS MORE FAVORED GIVEN TRACK OF
VORT. STEEP MID-LEVEL LAPSE RATES/EML SEEN IN UPSTREAM TOP/SGF 00Z
SOUNDINGS WILL APPROACH LATER IN THE DAY PER FORECAST SOUNDINGS...
WHICH MAY PROVIDE A BIT MORE CAPPING BY AFTERNOON WHICH ALONG WITH
MID-LEVEL WAVE SLOWLY LIFTING NORTH OF THE AREA MAY LIMIT COVERAGE
AT THAT TIME...THOUGH DIURNAL PEAK HEATING WILL LIKELY ALLOW FOR A
FEW SCATTERED STORMS TO CONTINUE. LOCALLY HEAVY RAINFALL WILL REMAIN
A POSSIBILITY WITH ANY STORMS THAT DEVELOP...WITH PRECIPITABLE WATER
VALUES IN EXCESS OF 1.7 INCHES.
A GREATER CHANCE OF MORE ORGANIZED THUNDERSTORMS IS EXPECTED LATER
TONIGHT INTO SUNDAY...AS A MORE AMPLIFIED SHORT WAVE PROPAGATES FROM
THE PLAINS TO THE UPPER MIDWEST AND NORTHERN GREAT LAKES THROUGH
SUNDAY MORNING. MODEST ORGANIZED HEIGHT FALLS WITH THIS FEATURE AS
WELL AS MODESTLY INCREASED MOISTURE TRANSPORT ON 30-35 KT SOUTHWEST
LOW LEVEL JET SHOULD HELP OFFSET POOR DIURNAL TIMING...THOUGH HAVE
GENERALLY GONE WITH LOWER RANGE OF GUIDANCE POPS WITH HIGH CHANCE/50
PERCENT RANGE DURING THE LATE NIGHT/SUNDAY MORNING PERIOD. HAVE
MAINTAINED CHANCE POPS INTO SUNDAY AFTERNOON MAINLY SOUTHEAST OF A
PONTIAC TO GARY LINE...AND LOWERED POPS TO A SLIGHT 20 PERCENT
NORTHWEST OF IT. LARGE SCALE FORCING DECREASES BEHIND DEPARTING
SHORT WAVE TROUGH AXIS SUNDAY AFTERNOON...THOUGH NAM FORECAST
SOUNDINGS MAINTAIN CONSIDERABLE MLCAPE WITH LITTLE/NO CAP ACROSS THE
REGION. GFS AND LOCAL WRF RUN DEPICT A STRONGER CAP WHICH APPEARS A
BIT MORE LIKELY GIVEN HEIGHT RISES...SUPPORTING LOW/NIL POPS ACROSS
NORTHERN IL FOR THE AFTERNOON/EVENING HOURS. WESTERLY FLOW ALOFT
STRENGTHENS ACROSS PLAINS/UPPER MIDWEST BY SUNDAY NIGHT...WITH THE
RESULTING INCREASE IN DEEP LAYER WIND SHEAR SUPPORTING DEVELOPMENT
OF POTENTIALLY SEVERE STORMS ACROSS AREAS TO OUR WEST. OUR CHANCE OF
THUNDERSTORMS LOOKS TO INCREASE ONCE AGAIN LATE SUNDAY NIGHT INTO
MONDAY AS LARGE-SCALE UPPER TROUGH DEVELOPS ACROSS THE REGION AND
SURFACE COLD FRONT EVENTUALLY MOVES THROUGH THE AREA LATE MONDAY.
GUIDANCE IN GENERAL AGREEMENT IN THUNDERSTORM POTENTIAL INCREASING
MAINLY ACROSS NORTH CENTRAL IL LATE SUNDAY NIGHT...THEN SPREADING
ACROSS THE REMAINDER OF THE CWA MONDAY/MONDAY NIGHT. INCREASED DEEP
SHEAR WITH STRONGER JET ALOFT...AND INSTABILITY FED BY POOLING OF
HIGHER DEW POINT AIR AHEAD OF COLD FRONT INDICATES THE POTENTIAL FOR
SEVERE STORMS FOR THE FORECAST AREA MONDAY...AS DEPICTED IN SPC DAY 3
OUTLOOK.
GUIDANCE WAS SIGNIFICANTLY COOL WITH TEMPS FRIDAY...AND IT APPEARS
THIS BIAS CONTINUES TODAY...SUNDAY AND POTENTIALLY MONDAY. HAVE GONE
ABOVE MOS NUMBERS BASED ON LOCAL 850 HPA TEMP CLIMO...THOUGH
INCREASED CLOUD COVER MAY COMPLICATE THINGS A BIT. SUNDAY AND MONDAY
HAVE THE POTENTIAL TO BE VERY WARM...LOW 90S IN SPOTS...DEPENDENT ON
AMOUNT OF CLOUDS.
ONCE COLD FRONT CLEARS AREA MONDAY NIGHT...A GRADUAL COOLING TREND
SETS UP FOR THE MID/LATE WEEK PERIOD. NORTHWEST FLOW WITH A COUPLE
OF SHORT WAVE IMPULSES NOTED TUES-WED WHICH MAY PRODUCE A FEW
SCATTERED AFTERNOON SHOWERS THOSE DAYS...BUT HIGH PRESSURE BUILDS IN
BY THE 4TH WHICH SHOULD ALLOW FOR PLEASANT HOLIDAY WEATHER WITH
TEMPS NEAR 80 AND 70S NEAR THE LAKE. LONGER RANGE MODEL SOLUTIONS
INDICATE A RETURN OF WARMER WEATHER OVER THE HOLIDAY WEEKEND...JUST
BEYOND THE CURRENT FORECAST PERIOD.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* ISOLATED THUNDERSTORMS THIS AFTERNOON/EVENING THEN ANOTHER CHANCE OF
THUNDERSTORMS OVERNIGHT INTO EARLY SUNDAY.
* GUSTY SOUTH WINDS.
BMD
//DISCUSSION...UPDATED 18Z...
LOW PRESSURE IS LIFTING ACROSS THE NORTHERN PLAINS THIS AFTERNOON
WITH SOUTHERLY FLOW IN PLACE ACROSS MUCH OF THE MIDWEST. UNSTABLE
CONDITIONS ARE IN PLACE WITH A REMNANT MCV LIFTING NE ACROSS WEST
CENTRAL ILLINOIS KICKING OFF WIDELY SCATTERED THUNDERSTORMS ACROSS
EAST CENTRAL AND NORTHEAST ILLINOIS. OVERALL THE FORCING REMAINS
FAIRLY WEAK ACROSS THE AREA SO DO NOT ANTICIPATE COVERAGE TO
GREATLY INCREASE. WILL HAVE TO MONITOR NEAR TERM TRENDS TO SEE IF
SOMETHING MAY IMPACT THE TERMINALS DIRECTLY. OTHERWISE...GUSTY SOUTH
WINDS WILL CONTINUE THROUGH THE AFTERNOON AND EVENING.
TONIGHT A NEGATIVELY TILTED TROUGH WILL LIFT FROM THE CENTRAL PLAINS
INTO THE UPPER MISSISSIPPI VALLEY KICKING OFF ADDITIONAL
THUNDERSTORMS TO OUR WEST. THESE STORMS MAY CONGEAL INTO A LINE OF
THUNDERSTORMS THAT WILL BEGIN TO MOVE ACROSS NORTHERN ILLINOIS LATE
OVERNIGHT TOWARDS DAYBREAK SUNDAY. IF THIS OCCURS...TSRA WOULD
EXPECTED TO BE IN A WEAKENING TREND AS IT NEARS THE CHICAGO
TERMINALS. WINDS WILL BE MORE SOUTHWESTERLY DURING THE DAY SUNDAY
WITH GUSTY WINDS CONTINUING.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM-HIGH CONFIDENCE IN WIND DIRECTION/SPEED.
* MEDIUM CONFIDENCE IN ISOLATED TSRA THIS AFTERNOON/EVENING.
* LOW CONFIDENCE IN TSRA OVERNIGHT/EARLY SUNDAY.
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
* SUNDAY NIGHT...CHANCE OF TSRA LATE.
* MONDAY...TSRA LIKELY.
* TUESDAY AND WEDNESDAY...SLIGHT CHANCE SHRA.
* THURSDAY AND FRIDAY...DRY/VFR.
&&
.MARINE...
155 PM CDT
VISIBLE SATELLITE IMAGERY SHOWS SOME AREAS OF FOG...MAINLY CLOSE TO
THE WISCONSIN SHORE...AND GIVEN THE MODEST GRADIENT AND WARMER
TEMPERATURES ADVECTING IN BELIEVE THE THREAT OF WIDESPREAD DENSE FOG
IS FAIRLY LOW. MAINLY SOUTH TO SOUTHEAST WINDS LIKELY TO PERSIST THE
NEXT SEVERAL DAYS BEFORE THE WEAKENING LOW TRACKS EAST TOWARD HUDSON
BAY RESULTING IN A STRENGTHENING PRESSURE GRADIENT LATER SUNDAY
NIGHT INTO MONDAY. WIND SHIFT TO WEST BEHIND THE FRONT THOUGH STABLE
CONDITIONS OVER THE OPEN WATER WILL LIKELY RESULT IN A BACKED
(SOUTHERLY) AND LIGHTER FLOW.
IZZI
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
155 PM CDT SAT JUN 28 2014
.DISCUSSION...
1047 AM CDT
SMALL BUT WELL DEFINED MCV OVER WEST CENTRAL ILLINOIS IS TWIRLING
VERY SLOWLY EASTWARD. MID LEVEL CLOUDINESS IS PRETTY EXTENSIVE
WITH THIS FEATURE...THOUGH NARROW RIBBON OF SOME CLEARING OVER
EASTERN ILLINOIS HAS ALLOWED FOR SOME BETTER INSOLATION AND
SUBSEQUENT INSTABILITY. ILX AND DVN SOUNDINGS THIS MORNING WERE
VERY MOIST AND MODIFYING FOR CURRENT CONDITIONS ACROSS THE AREA
YIELD MLCAPE VALUES NEARING 2000 J/KG WITH VERY LITTLE CINH.
ALREADY SEEING SOME CONVECTION BEGIN TO POP WITHIN THAT CLEARING
AREA AND SUSPECT THIS TREND WILL CONTINUE WITH COVERAGE INCREASING
OVER MAINLY THE EASTERN 1/3RD OF CWA THROUGH EARLY AFTERNOON. VERY
WEAK VERTICAL SHEAR SHOULD RESULT IN PULSY AND RATHER UNORGANIZED
STORMS.
ANY CLEARING OF THE MID LEVEL DECK UPSTREAM COULD ALSO BE ENOUGH
FOR CONVECTIVE TEMP TO BE REACHED AND SCTD STORMS TO DEVELOP THERE
THIS AFTERNOON AS WELL. OVERALL THINK GOING FORECAST OF ISOLD-SCTD
SHOWERS AND STORMS THIS AFTERNOON ADEQUATELY COVERS EXPECTATIONS.
MORE EXTENSIVE CLOUD COVER IS LOOKING LIKELY TO KEEP TEMPS DOWN A
BIT AND HAVE SHAVED HIGHS TODAY DOWN BY NEARLY A CATEGORY...THOUGH
WITH JUICY DEWPOINTS NEAR 70 IT WILL STILL FEEL PRETTY TOASTY.
IZZI
//PREV DISCUSSION...
355 AM CDT
MAIN FORECAST CHALLENGES ARE THUNDERSTORM CHANCES AND TEMPERATURES
WITH WARM/HUMID CONDITIONS THROUGH MONDAY...THEN GRADUAL COOLING
TUESDAY-WEDNESDAY. HIGH PRESSURE LATE IN THE WEEK SHOULD MAKE FOR
NICE WEATHER FOR THE JULY 4TH HOLIDAY...WITH SIGNS OF WARMER WEATHER
RETURNING OVER THE HOLIDAY WEEKEND.
RATHER INDISTINCT SURFACE WARM FRONT WAS ANALYZED FROM THE UPPER
MIDWEST...SOUTHEAST ACROSS ILLINOIS AND INTO CENTRAL INDIANA EARLY
THIS MORNING. THIS WARM FRONT WILL CONTINUE TO LIFT ACROSS THE
FORECAST AREA THIS MORNING...WITHIN BROAD SOUTHERLY RETURN FLOW IN
LOW LEVELS AHEAD OF LOW PRESSURE OVER THE PLAINS. WARM/MOIST AIR
MASS CHARACTERIZED BY TEMPS IN THE LOW-MID 70S AND DEW POINTS OF
65-70 IS EXPECTED TO DESTABILIZE AFTER SUNRISE...WITH FORECAST
SOUNDINGS FROM 06Z RAP DEPICTING LITTLE/NO CAP AND MLCAPE
APPROACHING 1000 J/KG BY MID/LATE MORNING. SIMILAR TO THE PAST FEW
DAYS...WEAK FLOW ALOFT AND LACK OF STRONG LOW LEVEL CONVERGENT FOCUS
SUGGESTS ONLY ISOLATED TO SCATTERED COVERAGE OF SHOWERS AND
THUNDERSTORMS TODAY. WEAK MID-LEVEL SHORT WAVE IS NOTED OVER THE
REGION THIS MORNING HOWEVER...WITH SOME PERSISTENT WEAK RADAR
RETURNS VICINITY KBMI EVIDENCE OF VORT. PRESENCE OF THIS WEAK WAVE
AND EARLY DESTABILIZATION IS EXPECTED TO RESULT IN ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING BY LATE MORNING WITH
EASTERN PORTIONS OF THE CWA PERHAPS MORE FAVORED GIVEN TRACK OF
VORT. STEEP MID-LEVEL LAPSE RATES/EML SEEN IN UPSTREAM TOP/SGF 00Z
SOUNDINGS WILL APPROACH LATER IN THE DAY PER FORECAST SOUNDINGS...
WHICH MAY PROVIDE A BIT MORE CAPPING BY AFTERNOON WHICH ALONG WITH
MID-LEVEL WAVE SLOWLY LIFTING NORTH OF THE AREA MAY LIMIT COVERAGE
AT THAT TIME...THOUGH DIURNAL PEAK HEATING WILL LIKELY ALLOW FOR A
FEW SCATTERED STORMS TO CONTINUE. LOCALLY HEAVY RAINFALL WILL REMAIN
A POSSIBILITY WITH ANY STORMS THAT DEVELOP...WITH PRECIPITABLE WATER
VALUES IN EXCESS OF 1.7 INCHES.
A GREATER CHANCE OF MORE ORGANIZED THUNDERSTORMS IS EXPECTED LATER
TONIGHT INTO SUNDAY...AS A MORE AMPLIFIED SHORT WAVE PROPAGATES FROM
THE PLAINS TO THE UPPER MIDWEST AND NORTHERN GREAT LAKES THROUGH
SUNDAY MORNING. MODEST ORGANIZED HEIGHT FALLS WITH THIS FEATURE AS
WELL AS MODESTLY INCREASED MOISTURE TRANSPORT ON 30-35 KT SOUTHWEST
LOW LEVEL JET SHOULD HELP OFFSET POOR DIURNAL TIMING...THOUGH HAVE
GENERALLY GONE WITH LOWER RANGE OF GUIDANCE POPS WITH HIGH CHANCE/50
PERCENT RANGE DURING THE LATE NIGHT/SUNDAY MORNING PERIOD. HAVE
MAINTAINED CHANCE POPS INTO SUNDAY AFTERNOON MAINLY SOUTHEAST OF A
PONTIAC TO GARY LINE...AND LOWERED POPS TO A SLIGHT 20 PERCENT
NORTHWEST OF IT. LARGE SCALE FORCING DECREASES BEHIND DEPARTING
SHORT WAVE TROUGH AXIS SUNDAY AFTERNOON...THOUGH NAM FORECAST
SOUNDINGS MAINTAIN CONSIDERABLE MLCAPE WITH LITTLE/NO CAP ACROSS THE
REGION. GFS AND LOCAL WRF RUN DEPICT A STRONGER CAP WHICH APPEARS A
BIT MORE LIKELY GIVEN HEIGHT RISES...SUPPORTING LOW/NIL POPS ACROSS
NORTHERN IL FOR THE AFTERNOON/EVENING HOURS. WESTERLY FLOW ALOFT
STRENGTHENS ACROSS PLAINS/UPPER MIDWEST BY SUNDAY NIGHT...WITH THE
RESULTING INCREASE IN DEEP LAYER WIND SHEAR SUPPORTING DEVELOPMENT
OF POTENTIALLY SEVERE STORMS ACROSS AREAS TO OUR WEST. OUR CHANCE OF
THUNDERSTORMS LOOKS TO INCREASE ONCE AGAIN LATE SUNDAY NIGHT INTO
MONDAY AS LARGE-SCALE UPPER TROUGH DEVELOPS ACROSS THE REGION AND
SURFACE COLD FRONT EVENTUALLY MOVES THROUGH THE AREA LATE MONDAY.
GUIDANCE IN GENERAL AGREEMENT IN THUNDERSTORM POTENTIAL INCREASING
MAINLY ACROSS NORTH CENTRAL IL LATE SUNDAY NIGHT...THEN SPREADING
ACROSS THE REMAINDER OF THE CWA MONDAY/MONDAY NIGHT. INCREASED DEEP
SHEAR WITH STRONGER JET ALOFT...AND INSTABILITY FED BY POOLING OF
HIGHER DEW POINT AIR AHEAD OF COLD FRONT INDICATES THE POTENTIAL FOR
SEVERE STORMS FOR THE FORECAST AREA MONDAY...AS DEPICTED IN SPC DAY 3
OUTLOOK.
GUIDANCE WAS SIGNIFICANTLY COOL WITH TEMPS FRIDAY...AND IT APPEARS
THIS BIAS CONTINUES TODAY...SUNDAY AND POTENTIALLY MONDAY. HAVE GONE
ABOVE MOS NUMBERS BASED ON LOCAL 850 HPA TEMP CLIMO...THOUGH
INCREASED CLOUD COVER MAY COMPLICATE THINGS A BIT. SUNDAY AND MONDAY
HAVE THE POTENTIAL TO BE VERY WARM...LOW 90S IN SPOTS...DEPENDENT ON
AMOUNT OF CLOUDS.
ONCE COLD FRONT CLEARS AREA MONDAY NIGHT...A GRADUAL COOLING TREND
SETS UP FOR THE MID/LATE WEEK PERIOD. NORTHWEST FLOW WITH A COUPLE
OF SHORT WAVE IMPULSES NOTED TUES-WED WHICH MAY PRODUCE A FEW
SCATTERED AFTERNOON SHOWERS THOSE DAYS...BUT HIGH PRESSURE BUILDS IN
BY THE 4TH WHICH SHOULD ALLOW FOR PLEASANT HOLIDAY WEATHER WITH
TEMPS NEAR 80 AND 70S NEAR THE LAKE. LONGER RANGE MODEL SOLUTIONS
INDICATE A RETURN OF WARMER WEATHER OVER THE HOLIDAY WEEKEND...JUST
BEYOND THE CURRENT FORECAST PERIOD.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* WIDELY SCATTERED THUNDERSTORMS THIS AFTERNOON/EVENING THEN
ANOTHER CHANCE OF THUNDERSTORMS OVERNIGHT INTO EARLY SUNDAY.
* GUSTY SOUTH WINDS.
BMD
//DISCUSSION...UPDATED 18Z...
LOW PRESSURE IS LIFTING ACROSS THE NORTHERN PLAINS THIS AFTERNOON
WITH SOUTHERLY FLOW IN PLACE ACROSS MUCH OF THE MIDWEST. UNSTABLE
CONDITIONS ARE IN PLACE WITH A REMNANT MCV LIFTING NE ACROSS WEST
CENTRAL ILLINOIS KICKING OFF WIDELY SCATTERED THUNDERSTORMS ACROSS
EAST CENTRAL AND NORTHEAST ILLINOIS. OVERALL THE FORCING REMAINS
FAIRLY WEAK ACROSS THE AREA SO DO NOT ANTICIPATE COVERAGE TO
GREATLY INCREASE. WILL HAVE TO MONITOR NEAR TERM TRENDS TO SEE IF
SOMETHING MAY IMPACT THE TERMINALS DIRECTLY. OTHERWISE...GUSTY SOUTH
WINDS WILL CONTINUE THROUGH THE AFTERNOON AND EVENING.
TONIGHT A NEGATIVELY TILTED TROUGH WILL LIFT FROM THE CENTRAL PLAINS
INTO THE UPPER MISSISSIPPI VALLEY KICKING OFF ADDITIONAL
THUNDERSTORMS TO OUR WEST. THESE STORMS MAY CONGEAL INTO A LINE OF
THUNDERSTORMS THAT WILL BEGIN TO MOVE ACROSS NORTHERN ILLINOIS LATE
OVERNIGHT TOWARDS DAYBREAK SUNDAY. IF THIS OCCURS...TSRA WOULD
EXPECTED TO BE IN A WEAKENING TREND AS IT NEARS THE CHICAGO
TERMINALS. WINDS WILL BE MORE SOUTHWESTERLY DURING THE DAY SUNDAY
WITH GUSTY WINDS CONTINUING.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM-HIGH CONFIDENCE IN WIND DIRECTION/SPEED.
* MEDIUM CONFIDENCE IN WIDELY SCATTERED TSRA THIS AFTERNOON.
* LOW CONFIDENCE IN TSRA OVERNIGHT/EARLY SUNDAY.
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
* SUNDAY NIGHT...CHANCE OF TSRA LATE.
* MONDAY...TSRA LIKELY.
* TUESDAY AND WEDNESDAY...SLIGHT CHANCE SHRA.
* THURSDAY AND FRIDAY...DRY/VFR.
&&
.MARINE...
155 PM CDT
VISIBLE SATELLITE IMAGERY SHOWS SOME AREAS OF FOG...MAINLY CLOSE TO
THE WISCONSIN SHORE...AND GIVEN THE MODEST GRADIENT AND WARMER
TEMPERATURES ADVECTING IN BELIEVE THE THREAT OF WIDESPREAD DENSE FOG
IS FAIRLY LOW. MAINLY SOUTH TO SOUTHEAST WINDS LIKELY TO PERSIST THE
NEXT SEVERAL DAYS BEFORE THE WEAKENING LOW TRACKS EAST TOWARD HUDSON
BAY RESULTING IN A STRENGTHENING PRESSURE GRADIENT LATER SUNDAY
NIGHT INTO MONDAY. WIND SHIFT TO WEST BEHIND THE FRONT THOUGH STABLE
CONDITIONS OVER THE OPEN WATER WILL LIKELY RESULT IN A BACKED
(SOUTHERLY) AND LIGHTER FLOW.
IZZI
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1235 PM CDT SAT JUN 28 2014
.DISCUSSION...
1047 AM CDT
SMALL BUT WELL DEFINED MCV OVER WEST CENTRAL ILLINOIS IS TWIRLING
VERY SLOWLY EASTWARD. MID LEVEL CLOUDINESS IS PRETTY EXTENSIVE
WITH THIS FEATURE...THOUGH NARROW RIBBON OF SOME CLEARING OVER
EASTERN ILLINOIS HAS ALLOWED FOR SOME BETTER INSOLATION AND
SUBSEQUENT INSTABILITY. ILX AND DVN SOUNDINGS THIS MORNING WERE
VERY MOIST AND MODIFYING FOR CURRENT CONDITIONS ACROSS THE AREA
YIELD MLCAPE VALUES NEARING 2000 J/KG WITH VERY LITTLE CINH.
ALREADY SEEING SOME CONVECTION BEGIN TO POP WITHIN THAT CLEARING
AREA AND SUSPECT THIS TREND WILL CONTINUE WITH COVERAGE INCREASING
OVER MAINLY THE EASTERN 1/3RD OF CWA THROUGH EARLY AFTERNOON. VERY
WEAK VERTICAL SHEAR SHOULD RESULT IN PULSY AND RATHER UNORGANIZED
STORMS.
ANY CLEARING OF THE MID LEVEL DECK UPSTREAM COULD ALSO BE ENOUGH
FOR CONVECTIVE TEMP TO BE REACHED AND SCTD STORMS TO DEVELOP THERE
THIS AFTERNOON AS WELL. OVERALL THINK GOING FORECAST OF ISOLD-SCTD
SHOWERS AND STORMS THIS AFTERNOON ADEQUATELY COVERS EXPECTATIONS.
MORE EXTENSIVE CLOUD COVER IS LOOKING LIKELY TO KEEP TEMPS DOWN A
BIT AND HAVE SHAVED HIGHS TODAY DOWN BY NEARLY A CATEGORY...THOUGH
WITH JUICY DEWPOINTS NEAR 70 IT WILL STILL FEEL PRETTY TOASTY.
IZZI
//PREV DISCUSSION...
355 AM CDT
MAIN FORECAST CHALLENGES ARE THUNDERSTORM CHANCES AND TEMPERATURES
WITH WARM/HUMID CONDITIONS THROUGH MONDAY...THEN GRADUAL COOLING
TUESDAY-WEDNESDAY. HIGH PRESSURE LATE IN THE WEEK SHOULD MAKE FOR
NICE WEATHER FOR THE JULY 4TH HOLIDAY...WITH SIGNS OF WARMER WEATHER
RETURNING OVER THE HOLIDAY WEEKEND.
RATHER INDISTINCT SURFACE WARM FRONT WAS ANALYZED FROM THE UPPER
MIDWEST...SOUTHEAST ACROSS ILLINOIS AND INTO CENTRAL INDIANA EARLY
THIS MORNING. THIS WARM FRONT WILL CONTINUE TO LIFT ACROSS THE
FORECAST AREA THIS MORNING...WITHIN BROAD SOUTHERLY RETURN FLOW IN
LOW LEVELS AHEAD OF LOW PRESSURE OVER THE PLAINS. WARM/MOIST AIR
MASS CHARACTERIZED BY TEMPS IN THE LOW-MID 70S AND DEW POINTS OF
65-70 IS EXPECTED TO DESTABILIZE AFTER SUNRISE...WITH FORECAST
SOUNDINGS FROM 06Z RAP DEPICTING LITTLE/NO CAP AND MLCAPE
APPROACHING 1000 J/KG BY MID/LATE MORNING. SIMILAR TO THE PAST FEW
DAYS...WEAK FLOW ALOFT AND LACK OF STRONG LOW LEVEL CONVERGENT FOCUS
SUGGESTS ONLY ISOLATED TO SCATTERED COVERAGE OF SHOWERS AND
THUNDERSTORMS TODAY. WEAK MID-LEVEL SHORT WAVE IS NOTED OVER THE
REGION THIS MORNING HOWEVER...WITH SOME PERSISTENT WEAK RADAR
RETURNS VICINITY KBMI EVIDENCE OF VORT. PRESENCE OF THIS WEAK WAVE
AND EARLY DESTABILIZATION IS EXPECTED TO RESULT IN ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING BY LATE MORNING WITH
EASTERN PORTIONS OF THE CWA PERHAPS MORE FAVORED GIVEN TRACK OF
VORT. STEEP MID-LEVEL LAPSE RATES/EML SEEN IN UPSTREAM TOP/SGF 00Z
SOUNDINGS WILL APPROACH LATER IN THE DAY PER FORECAST SOUNDINGS...
WHICH MAY PROVIDE A BIT MORE CAPPING BY AFTERNOON WHICH ALONG WITH
MID-LEVEL WAVE SLOWLY LIFTING NORTH OF THE AREA MAY LIMIT COVERAGE
AT THAT TIME...THOUGH DIURNAL PEAK HEATING WILL LIKELY ALLOW FOR A
FEW SCATTERED STORMS TO CONTINUE. LOCALLY HEAVY RAINFALL WILL REMAIN
A POSSIBILITY WITH ANY STORMS THAT DEVELOP...WITH PRECIPITABLE WATER
VALUES IN EXCESS OF 1.7 INCHES.
A GREATER CHANCE OF MORE ORGANIZED THUNDERSTORMS IS EXPECTED LATER
TONIGHT INTO SUNDAY...AS A MORE AMPLIFIED SHORT WAVE PROPAGATES FROM
THE PLAINS TO THE UPPER MIDWEST AND NORTHERN GREAT LAKES THROUGH
SUNDAY MORNING. MODEST ORGANIZED HEIGHT FALLS WITH THIS FEATURE AS
WELL AS MODESTLY INCREASED MOISTURE TRANSPORT ON 30-35 KT SOUTHWEST
LOW LEVEL JET SHOULD HELP OFFSET POOR DIURNAL TIMING...THOUGH HAVE
GENERALLY GONE WITH LOWER RANGE OF GUIDANCE POPS WITH HIGH CHANCE/50
PERCENT RANGE DURING THE LATE NIGHT/SUNDAY MORNING PERIOD. HAVE
MAINTAINED CHANCE POPS INTO SUNDAY AFTERNOON MAINLY SOUTHEAST OF A
PONTIAC TO GARY LINE...AND LOWERED POPS TO A SLIGHT 20 PERCENT
NORTHWEST OF IT. LARGE SCALE FORCING DECREASES BEHIND DEPARTING
SHORT WAVE TROUGH AXIS SUNDAY AFTERNOON...THOUGH NAM FORECAST
SOUNDINGS MAINTAIN CONSIDERABLE MLCAPE WITH LITTLE/NO CAP ACROSS THE
REGION. GFS AND LOCAL WRF RUN DEPICT A STRONGER CAP WHICH APPEARS A
BIT MORE LIKELY GIVEN HEIGHT RISES...SUPPORTING LOW/NIL POPS ACROSS
NORTHERN IL FOR THE AFTERNOON/EVENING HOURS. WESTERLY FLOW ALOFT
STRENGTHENS ACROSS PLAINS/UPPER MIDWEST BY SUNDAY NIGHT...WITH THE
RESULTING INCREASE IN DEEP LAYER WIND SHEAR SUPPORTING DEVELOPMENT
OF POTENTIALLY SEVERE STORMS ACROSS AREAS TO OUR WEST. OUR CHANCE OF
THUNDERSTORMS LOOKS TO INCREASE ONCE AGAIN LATE SUNDAY NIGHT INTO
MONDAY AS LARGE-SCALE UPPER TROUGH DEVELOPS ACROSS THE REGION AND
SURFACE COLD FRONT EVENTUALLY MOVES THROUGH THE AREA LATE MONDAY.
GUIDANCE IN GENERAL AGREEMENT IN THUNDERSTORM POTENTIAL INCREASING
MAINLY ACROSS NORTH CENTRAL IL LATE SUNDAY NIGHT...THEN SPREADING
ACROSS THE REMAINDER OF THE CWA MONDAY/MONDAY NIGHT. INCREASED DEEP
SHEAR WITH STRONGER JET ALOFT...AND INSTABILITY FED BY POOLING OF
HIGHER DEW POINT AIR AHEAD OF COLD FRONT INDICATES THE POTENTIAL FOR
SEVERE STORMS FOR THE FORECAST AREA MONDAY...AS DEPICTED IN SPC DAY 3
OUTLOOK.
GUIDANCE WAS SIGNIFICANTLY COOL WITH TEMPS FRIDAY...AND IT APPEARS
THIS BIAS CONTINUES TODAY...SUNDAY AND POTENTIALLY MONDAY. HAVE GONE
ABOVE MOS NUMBERS BASED ON LOCAL 850 HPA TEMP CLIMO...THOUGH
INCREASED CLOUD COVER MAY COMPLICATE THINGS A BIT. SUNDAY AND MONDAY
HAVE THE POTENTIAL TO BE VERY WARM...LOW 90S IN SPOTS...DEPENDENT ON
AMOUNT OF CLOUDS.
ONCE COLD FRONT CLEARS AREA MONDAY NIGHT...A GRADUAL COOLING TREND
SETS UP FOR THE MID/LATE WEEK PERIOD. NORTHWEST FLOW WITH A COUPLE
OF SHORT WAVE IMPULSES NOTED TUES-WED WHICH MAY PRODUCE A FEW
SCATTERED AFTERNOON SHOWERS THOSE DAYS...BUT HIGH PRESSURE BUILDS IN
BY THE 4TH WHICH SHOULD ALLOW FOR PLEASANT HOLIDAY WEATHER WITH
TEMPS NEAR 80 AND 70S NEAR THE LAKE. LONGER RANGE MODEL SOLUTIONS
INDICATE A RETURN OF WARMER WEATHER OVER THE HOLIDAY WEEKEND...JUST
BEYOND THE CURRENT FORECAST PERIOD.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* WIDELY SCATTERED THUNDERSTORMS THIS AFTERNOON/EVENING THEN
ANOTHER CHANCE OF THUNDERSTORMS OVERNIGHT INTO EARLY SUNDAY.
* GUSTY SOUTH WINDS.
BMD
//DISCUSSION...UPDATED 18Z...
LOW PRESSURE IS LIFTING ACROSS THE NORTHERN PLAINS THIS AFTERNOON
WITH SOUTHERLY FLOW IN PLACE ACROSS MUCH OF THE MIDWEST. UNSTABLE
CONDITIONS ARE IN PLACE WITH A REMNANT MCV LIFTING NE ACROSS WEST
CENTRAL ILLINOIS KICKING OFF WIDELY SCATTERED THUNDERSTORMS ACROSS
EAST CENTRAL AND NORTHEAST ILLINOIS. OVERALL THE FORCING REMAINS
FAIRLY WEAK ACROSS THE AREA SO DO NOT ANTICIPATE COVERAGE TO
GREATLY INCREASE. WILL HAVE TO MONITOR NEAR TERM TRENDS TO SEE IF
SOMETHING MAY IMPACT THE TERMINALS DIRECTLY. OTHERWISE...GUSTY SOUTH
WINDS WILL CONTINUE THROUGH THE AFTERNOON AND EVENING.
TONIGHT A NEGATIVELY TILTED TROUGH WILL LIFT FROM THE CENTRAL PLAINS
INTO THE UPPER MISSISSIPPI VALLEY KICKING OFF ADDITIONAL
THUNDERSTORMS TO OUR WEST. THESE STORMS MAY CONGEAL INTO A LINE OF
THUNDERSTORMS THAT WILL BEGIN TO MOVE ACROSS NORTHERN ILLINOIS LATE
OVERNIGHT TOWARDS DAYBREAK SUNDAY. IF THIS OCCURS...TSRA WOULD
EXPECTED TO BE IN A WEAKENING TREND AS IT NEARS THE CHICAGO
TERMINALS. WINDS WILL BE MORE SOUTHWESTERLY DURING THE DAY SUNDAY
WITH GUSTY WINDS CONTINUING.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM-HIGH CONFIDENCE IN WIND DIRECTION/SPEED.
* MEDIUM CONFIDENCE IN WIDELY SCATTERED TSRA THIS AFTERNOON.
* LOW CONFIDENCE IN TSRA OVERNIGHT/EARLY SUNDAY.
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
* SUNDAY NIGHT...CHANCE OF TSRA LATE.
* MONDAY...TSRA LIKELY.
* TUESDAY AND WEDNESDAY...SLIGHT CHANCE SHRA.
* THURSDAY AND FRIDAY...DRY/VFR.
&&
.MARINE...
240 AM...HIGH PRESSURE OVER NEW ENGLAND WILL SLOWLY DRIFT OFF THE
EAST COAST SUNDAY AND SUNDAY NIGHT. A LARGE TROUGH OF LOW PRESSURE
EXTENDING FROM MANITOBA TO KANSAS WILL SLOWLY DRIFT NORTH FORMING
A DEEP AREA OF LOW PRESSURE OVER SOUTHERN MANITOBA ON SUNDAY. THE
GRADIENT WILL SLOWLY TIGHTEN AS THIS OCCURS WITH SOUTHERLY WINDS
INCREASING INTO THE 15-25KT RANGE OVER LAKE MICHIGAN. THE LOW WILL
SLOWLY MOVE NORTHEAST REACHING JAMES BAY TUESDAY WITH A TRAILING
COLD FRONT MOVING ACROSS THE LAKE MONDAY NIGHT OR TUESDAY MORNING.
THE STRONGEST WINDS WILL LIKELY BE AHEAD OF THIS COLD FRONT...ON
MONDAY. WINDS THEN SHIFT WESTERLY BEHIND THE FRONT. THE STRONGER
WINDS ARE EXPECTED TO PREVENT ANY WIDESPREAD DENSE FOG OVER THE
LAKE BUT WILL MAINTAIN CURRENT HAZE/PATCHY DENSE FOG WORDING. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1101 AM CDT SAT JUN 28 2014
.DISCUSSION...
1047 AM CDT
SMALL BUT WELL DEFINED MCV OVER WEST CENTRAL ILLINOIS IS TWIRLING
VERY SLOWLY EASTWARD. MID LEVEL CLOUDINESS IS PRETTY EXTENSIVE
WITH THIS FEATURE...THOUGH NARROW RIBBON OF SOME CLEARING OVER
EASTERN ILLINOIS HAS ALLOWED FOR SOME BETTER INSOLATION AND
SUBSEQUENT INSTABILITY. ILX AND DVN SOUNDINGS THIS MORNING WERE
VERY MOIST AND MODIFYING FOR CURRENT CONDITIONS ACROSS THE AREA
YIELD MLCAPE VALUES NEARING 2000 J/KG WITH VERY LITTLE CINH.
ALREADY SEEING SOME CONVECTION BEGIN TO POP WITHIN THAT CLEARING
AREA AND SUSPECT THIS TREND WILL CONTINUE WITH COVERAGE INCREASING
OVER MAINLY THE EASTERN 1/3RD OF CWA THROUGH EARLY AFTERNOON. VERY
WEAK VERTICAL SHEAR SHOULD RESULT IN PULSY AND RATHER UNORGANIZED
STORMS.
ANY CLEARING OF THE MID LEVEL DECK UPSTREAM COULD ALSO BE ENOUGH
FOR CONVECTIVE TEMP TO BE REACHED AND SCTD STORMS TO DEVELOP THERE
THIS AFTERNOON AS WELL. OVERALL THINK GOING FORECAST OF ISOLD-SCTD
SHOWERS AND STORMS THIS AFTERNOON ADEQUATELY COVERS EXPECTATIONS.
MORE EXTENSIVE CLOUD COVER IS LOOKING LIKELY TO KEEP TEMPS DOWN A
BIT AND HAVE SHAVED HIGHS TODAY DOWN BY NEARLY A CATEGORY...THOUGH
WITH JUICY DEWPOINTS NEAR 70 IT WILL STILL FEEL PRETTY TOASTY.
IZZI
//PREV DISCUSSION...
355 AM CDT
MAIN FORECAST CHALLENGES ARE THUNDERSTORM CHANCES AND TEMPERATURES
WITH WARM/HUMID CONDITIONS THROUGH MONDAY...THEN GRADUAL COOLING
TUESDAY-WEDNESDAY. HIGH PRESSURE LATE IN THE WEEK SHOULD MAKE FOR
NICE WEATHER FOR THE JULY 4TH HOLIDAY...WITH SIGNS OF WARMER WEATHER
RETURNING OVER THE HOLIDAY WEEKEND.
RATHER INDISTINCT SURFACE WARM FRONT WAS ANALYZED FROM THE UPPER
MIDWEST...SOUTHEAST ACROSS ILLINOIS AND INTO CENTRAL INDIANA EARLY
THIS MORNING. THIS WARM FRONT WILL CONTINUE TO LIFT ACROSS THE
FORECAST AREA THIS MORNING...WITHIN BROAD SOUTHERLY RETURN FLOW IN
LOW LEVELS AHEAD OF LOW PRESSURE OVER THE PLAINS. WARM/MOIST AIR
MASS CHARACTERIZED BY TEMPS IN THE LOW-MID 70S AND DEW POINTS OF
65-70 IS EXPECTED TO DESTABILIZE AFTER SUNRISE...WITH FORECAST
SOUNDINGS FROM 06Z RAP DEPICTING LITTLE/NO CAP AND MLCAPE
APPROACHING 1000 J/KG BY MID/LATE MORNING. SIMILAR TO THE PAST FEW
DAYS...WEAK FLOW ALOFT AND LACK OF STRONG LOW LEVEL CONVERGENT FOCUS
SUGGESTS ONLY ISOLATED TO SCATTERED COVERAGE OF SHOWERS AND
THUNDERSTORMS TODAY. WEAK MID-LEVEL SHORT WAVE IS NOTED OVER THE
REGION THIS MORNING HOWEVER...WITH SOME PERSISTENT WEAK RADAR
RETURNS VICINITY KBMI EVIDENCE OF VORT. PRESENCE OF THIS WEAK WAVE
AND EARLY DESTABILIZATION IS EXPECTED TO RESULT IN ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING BY LATE MORNING WITH
EASTERN PORTIONS OF THE CWA PERHAPS MORE FAVORED GIVEN TRACK OF
VORT. STEEP MID-LEVEL LAPSE RATES/EML SEEN IN UPSTREAM TOP/SGF 00Z
SOUNDINGS WILL APPROACH LATER IN THE DAY PER FORECAST SOUNDINGS...
WHICH MAY PROVIDE A BIT MORE CAPPING BY AFTERNOON WHICH ALONG WITH
MID-LEVEL WAVE SLOWLY LIFTING NORTH OF THE AREA MAY LIMIT COVERAGE
AT THAT TIME...THOUGH DIURNAL PEAK HEATING WILL LIKELY ALLOW FOR A
FEW SCATTERED STORMS TO CONTINUE. LOCALLY HEAVY RAINFALL WILL REMAIN
A POSSIBILITY WITH ANY STORMS THAT DEVELOP...WITH PRECIPITABLE WATER
VALUES IN EXCESS OF 1.7 INCHES.
A GREATER CHANCE OF MORE ORGANIZED THUNDERSTORMS IS EXPECTED LATER
TONIGHT INTO SUNDAY...AS A MORE AMPLIFIED SHORT WAVE PROPAGATES FROM
THE PLAINS TO THE UPPER MIDWEST AND NORTHERN GREAT LAKES THROUGH
SUNDAY MORNING. MODEST ORGANIZED HEIGHT FALLS WITH THIS FEATURE AS
WELL AS MODESTLY INCREASED MOISTURE TRANSPORT ON 30-35 KT SOUTHWEST
LOW LEVEL JET SHOULD HELP OFFSET POOR DIURNAL TIMING...THOUGH HAVE
GENERALLY GONE WITH LOWER RANGE OF GUIDANCE POPS WITH HIGH CHANCE/50
PERCENT RANGE DURING THE LATE NIGHT/SUNDAY MORNING PERIOD. HAVE
MAINTAINED CHANCE POPS INTO SUNDAY AFTERNOON MAINLY SOUTHEAST OF A
PONTIAC TO GARY LINE...AND LOWERED POPS TO A SLIGHT 20 PERCENT
NORTHWEST OF IT. LARGE SCALE FORCING DECREASES BEHIND DEPARTING
SHORT WAVE TROUGH AXIS SUNDAY AFTERNOON...THOUGH NAM FORECAST
SOUNDINGS MAINTAIN CONSIDERABLE MLCAPE WITH LITTLE/NO CAP ACROSS THE
REGION. GFS AND LOCAL WRF RUN DEPICT A STRONGER CAP WHICH APPEARS A
BIT MORE LIKELY GIVEN HEIGHT RISES...SUPPORTING LOW/NIL POPS ACROSS
NORTHERN IL FOR THE AFTERNOON/EVENING HOURS. WESTERLY FLOW ALOFT
STRENGTHENS ACROSS PLAINS/UPPER MIDWEST BY SUNDAY NIGHT...WITH THE
RESULTING INCREASE IN DEEP LAYER WIND SHEAR SUPPORTING DEVELOPMENT
OF POTENTIALLY SEVERE STORMS ACROSS AREAS TO OUR WEST. OUR CHANCE OF
THUNDERSTORMS LOOKS TO INCREASE ONCE AGAIN LATE SUNDAY NIGHT INTO
MONDAY AS LARGE-SCALE UPPER TROUGH DEVELOPS ACROSS THE REGION AND
SURFACE COLD FRONT EVENTUALLY MOVES THROUGH THE AREA LATE MONDAY.
GUIDANCE IN GENERAL AGREEMENT IN THUNDERSTORM POTENTIAL INCREASING
MAINLY ACROSS NORTH CENTRAL IL LATE SUNDAY NIGHT...THEN SPREADING
ACROSS THE REMAINDER OF THE CWA MONDAY/MONDAY NIGHT. INCREASED DEEP
SHEAR WITH STRONGER JET ALOFT...AND INSTABILITY FED BY POOLING OF
HIGHER DEW POINT AIR AHEAD OF COLD FRONT INDICATES THE POTENTIAL FOR
SEVERE STORMS FOR THE FORECAST AREA MONDAY...AS DEPICTED IN SPC DAY 3
OUTLOOK.
GUIDANCE WAS SIGNIFICANTLY COOL WITH TEMPS FRIDAY...AND IT APPEARS
THIS BIAS CONTINUES TODAY...SUNDAY AND POTENTIALLY MONDAY. HAVE GONE
ABOVE MOS NUMBERS BASED ON LOCAL 850 HPA TEMP CLIMO...THOUGH
INCREASED CLOUD COVER MAY COMPLICATE THINGS A BIT. SUNDAY AND MONDAY
HAVE THE POTENTIAL TO BE VERY WARM...LOW 90S IN SPOTS...DEPENDENT ON
AMOUNT OF CLOUDS.
ONCE COLD FRONT CLEARS AREA MONDAY NIGHT...A GRADUAL COOLING TREND
SETS UP FOR THE MID/LATE WEEK PERIOD. NORTHWEST FLOW WITH A COUPLE
OF SHORT WAVE IMPULSES NOTED TUES-WED WHICH MAY PRODUCE A FEW
SCATTERED AFTERNOON SHOWERS THOSE DAYS...BUT HIGH PRESSURE BUILDS IN
BY THE 4TH WHICH SHOULD ALLOW FOR PLEASANT HOLIDAY WEATHER WITH
TEMPS NEAR 80 AND 70S NEAR THE LAKE. LONGER RANGE MODEL SOLUTIONS
INDICATE A RETURN OF WARMER WEATHER OVER THE HOLIDAY WEEKEND...JUST
BEYOND THE CURRENT FORECAST PERIOD.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* ISOLATED SHRA/TSRA MID MORNING THRU LATE AFTERNOON.
* GUSTY SOUTHERLY WINDS MID MORNING THRU SUNSET.
* CHANCE OF SHRA/TSRA SUNDAY MORNING. CMS/BMD
//DISCUSSION...UPDATED 12Z...
A WEAK UPPER WAVE WILL MOVE ACROSS THE AREA LATER THIS MORNING
INTO THIS AFTERNOON AND IS EXPECTED TO AID TSRA DEVELOPMENT BUT
TIMING AND COVERAGE REMAIN UNCERTAIN...THOUGH HI RES/SHORT TERM
GUIDANCE SUGGEST SHRA DEVELOPMENT BY MID MORNING. WITH DEWPOINTS
IN THE MID/UPPER 60S...AS TEMPS WARM DURING THE MORNING...SOME
ISOLATED ACTIVITY IS CERTAINLY POSSIBLE. BUT BEST TIMING FOR TSRA
APPEARS TO BE IN THE EARLY/MID AFTERNOON AS THE UPPER WAVE
ARRIVES. AS THIS WAVE DEPARTS LATER THIS AFTERNOON...EXPECT SOME
DECREASE IN COVERAGE BUT ISOLATED ACTIVITY MAY CONTINUE THROUGH
SUNSET.
ADDITIONAL TSRA EXPECTED TO DEVELOP FURTHER WEST TODAY AND THEN
MOVE EAST TONIGHT AND POTENTIALLY ACROSS THE TERMINALS EARLY/MID
SUNDAY MORNING. CONFIDENCE IS FAIRLY LOW REGARDING HOW MUCH OF
THIS ACTIVITY WILL REACH THE TERMINALS.
SOUTH/SOUTHEAST WINDS AROUND 10KTS WILL INCREASE INTO THE 12-16KT
RANGE THROUGH LATE MORNING WITH HIGHER GUSTS INTO THE 20KT RANGE
AND WINDS SHOULD TURN MORE SOUTHERLY BY LATE MORNING. CMS
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* LOW-MEDIUM FOR ISOLATED SHRA/TSRA THRU LATE AFTERNOON...LOW FOR
COVERAGE AND TIMING.
* MEDIUM FOR WINDS THRU THE PERIOD.
* LOW FOR SHRA/TSRA SUNDAY MORNING. CMS/BMD
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
* SUNDAY NIGHT...CHANCE OF TSRA LATE.
* MONDAY...TSRA LIKELY.
* TUESDAY AND WEDNESDAY...SLIGHT CHANCE SHRA.
* THURSDAY AND FRIDAY...DRY/VFR.
&&
.MARINE...
240 AM...HIGH PRESSURE OVER NEW ENGLAND WILL SLOWLY DRIFT OFF THE
EAST COAST SUNDAY AND SUNDAY NIGHT. A LARGE TROUGH OF LOW PRESSURE
EXTENDING FROM MANITOBA TO KANSAS WILL SLOWLY DRIFT NORTH FORMING
A DEEP AREA OF LOW PRESSURE OVER SOUTHERN MANITOBA ON SUNDAY. THE
GRADIENT WILL SLOWLY TIGHTEN AS THIS OCCURS WITH SOUTHERLY WINDS
INCREASING INTO THE 15-25KT RANGE OVER LAKE MICHIGAN. THE LOW WILL
SLOWLY MOVE NORTHEAST REACHING JAMES BAY TUESDAY WITH A TRAILING
COLD FRONT MOVING ACROSS THE LAKE MONDAY NIGHT OR TUESDAY MORNING.
THE STRONGEST WINDS WILL LIKELY BE AHEAD OF THIS COLD FRONT...ON
MONDAY. WINDS THEN SHIFT WESTERLY BEHIND THE FRONT. THE STRONGER
WINDS ARE EXPECTED TO PREVENT ANY WIDESPREAD DENSE FOG OVER THE
LAKE BUT WILL MAINTAIN CURRENT HAZE/PATCHY DENSE FOG WORDING. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1047 AM CDT SAT JUN 28 2014
.DISCUSSION...
1047 AM CDT
SMALL BUT WELL DEFINED MCV OVER WEST CENTRAL ILLINOIS IS TWIRLING
VERY SLOWLY EASTWARD. MID LEVEL CLOUDINESS IS PRETTY EXTENSIVE
WITH THIS FEATURE...THOUGH NARROW RIBBON OF SOME CLEARING OVER
EASTERN ILLINOIS HAS ALLOWED FOR SOME BETTER INSOLATION AND
SUBSEQUENT INSTABILITY. ILX AND DVN SOUNDINGS THIS MORNING WERE
VERY MOIST AND MODIFYING FOR CURRENT CONDITIONS ACROSS THE AREA
YIELD MLCAPE VALUES NEARING 2000 J/KG WITH VERY LITTLE CINH.
ALREADY SEEING SOME CONVECTION BEGIN TO POP WITHIN THAT CLEARING
AREA AND SUSPECT THIS TREND WILL CONTINUE WITH COVERAGE INCREASING
OVER MAINLY THE EASTERN 1/3RD OF CWA THROUGH EARLY AFTERNOON. VERY
WEAK VERTICAL SHEAR SHOULD RESULT IN PULSY AND RATHER UNORGANIZED
STORMS.
ANY CLEARING OF THE MID LEVEL DECK UPSTREAM COULD ALSO BE ENOUGH
FOR CONVECTIVE TEMP TO BE REACHED AND SCTD STORMS TO DEVELOP THERE
THIS AFTERNOON AS WELL. OVERALL THINK GOING FORECAST OF ISOLD-SCTD
SHOWERS AND STORMS THIS AFTERNOON ADEQUATELY COVERS EXPECTATIONS.
MORE EXTENSIVE CLOUD COVER IS LOOKING LIKELY TO KEEP TEMPS DOWN A
BIT AND HAVE SHAVED HIGHS TODAY DOWN BY NEARLY A CATEGORY...THOUGH
WITH JUICY DEWPOINTS NEAR 70 IT WILL STILL FEEL PRETTY TOASTY.
IZZI
&&
.PREV DISCUSSION...
355 AM CDT
MAIN FORECAST CHALLENGES ARE THUNDERSTORM CHANCES AND TEMPERATURES
WITH WARM/HUMID CONDITIONS THROUGH MONDAY...THEN GRADUAL COOLING
TUESDAY-WEDNESDAY. HIGH PRESSURE LATE IN THE WEEK SHOULD MAKE FOR
NICE WEATHER FOR THE JULY 4TH HOLIDAY...WITH SIGNS OF WARMER WEATHER
RETURNING OVER THE HOLIDAY WEEKEND.
RATHER INDISTINCT SURFACE WARM FRONT WAS ANALYZED FROM THE UPPER
MIDWEST...SOUTHEAST ACROSS ILLINOIS AND INTO CENTRAL INDIANA EARLY
THIS MORNING. THIS WARM FRONT WILL CONTINUE TO LIFT ACROSS THE
FORECAST AREA THIS MORNING...WITHIN BROAD SOUTHERLY RETURN FLOW IN
LOW LEVELS AHEAD OF LOW PRESSURE OVER THE PLAINS. WARM/MOIST AIR
MASS CHARACTERIZED BY TEMPS IN THE LOW-MID 70S AND DEW POINTS OF
65-70 IS EXPECTED TO DESTABILIZE AFTER SUNRISE...WITH FORECAST
SOUNDINGS FROM 06Z RAP DEPICTING LITTLE/NO CAP AND MLCAPE
APPROACHING 1000 J/KG BY MID/LATE MORNING. SIMILAR TO THE PAST FEW
DAYS...WEAK FLOW ALOFT AND LACK OF STRONG LOW LEVEL CONVERGENT FOCUS
SUGGESTS ONLY ISOLATED TO SCATTERED COVERAGE OF SHOWERS AND
THUNDERSTORMS TODAY. WEAK MID-LEVEL SHORT WAVE IS NOTED OVER THE
REGION THIS MORNING HOWEVER...WITH SOME PERSISTENT WEAK RADAR
RETURNS VICINITY KBMI EVIDENCE OF VORT. PRESENCE OF THIS WEAK WAVE
AND EARLY DESTABILIZATION IS EXPECTED TO RESULT IN ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING BY LATE MORNING WITH
EASTERN PORTIONS OF THE CWA PERHAPS MORE FAVORED GIVEN TRACK OF
VORT. STEEP MID-LEVEL LAPSE RATES/EML SEEN IN UPSTREAM TOP/SGF 00Z
SOUNDINGS WILL APPROACH LATER IN THE DAY PER FORECAST SOUNDINGS...
WHICH MAY PROVIDE A BIT MORE CAPPING BY AFTERNOON WHICH ALONG WITH
MID-LEVEL WAVE SLOWLY LIFTING NORTH OF THE AREA MAY LIMIT COVERAGE
AT THAT TIME...THOUGH DIURNAL PEAK HEATING WILL LIKELY ALLOW FOR A
FEW SCATTERED STORMS TO CONTINUE. LOCALLY HEAVY RAINFALL WILL REMAIN
A POSSIBILITY WITH ANY STORMS THAT DEVELOP...WITH PRECIPITABLE WATER
VALUES IN EXCESS OF 1.7 INCHES.
A GREATER CHANCE OF MORE ORGANIZED THUNDERSTORMS IS EXPECTED LATER
TONIGHT INTO SUNDAY...AS A MORE AMPLIFIED SHORT WAVE PROPAGATES FROM
THE PLAINS TO THE UPPER MIDWEST AND NORTHERN GREAT LAKES THROUGH
SUNDAY MORNING. MODEST ORGANIZED HEIGHT FALLS WITH THIS FEATURE AS
WELL AS MODESTLY INCREASED MOISTURE TRANSPORT ON 30-35 KT SOUTHWEST
LOW LEVEL JET SHOULD HELP OFFSET POOR DIURNAL TIMING...THOUGH HAVE
GENERALLY GONE WITH LOWER RANGE OF GUIDANCE POPS WITH HIGH CHANCE/50
PERCENT RANGE DURING THE LATE NIGHT/SUNDAY MORNING PERIOD. HAVE
MAINTAINED CHANCE POPS INTO SUNDAY AFTERNOON MAINLY SOUTHEAST OF A
PONTIAC TO GARY LINE...AND LOWERED POPS TO A SLIGHT 20 PERCENT
NORTHWEST OF IT. LARGE SCALE FORCING DECREASES BEHIND DEPARTING
SHORT WAVE TROUGH AXIS SUNDAY AFTERNOON...THOUGH NAM FORECAST
SOUNDINGS MAINTAIN CONSIDERABLE MLCAPE WITH LITTLE/NO CAP ACROSS THE
REGION. GFS AND LOCAL WRF RUN DEPICT A STRONGER CAP WHICH APPEARS A
BIT MORE LIKELY GIVEN HEIGHT RISES...SUPPORTING LOW/NIL POPS ACROSS
NORTHERN IL FOR THE AFTERNOON/EVENING HOURS. WESTERLY FLOW ALOFT
STRENGTHENS ACROSS PLAINS/UPPER MIDWEST BY SUNDAY NIGHT...WITH THE
RESULTING INCREASE IN DEEP LAYER WIND SHEAR SUPPORTING DEVELOPMENT
OF POTENTIALLY SEVERE STORMS ACROSS AREAS TO OUR WEST. OUR CHANCE OF
THUNDERSTORMS LOOKS TO INCREASE ONCE AGAIN LATE SUNDAY NIGHT INTO
MONDAY AS LARGE-SCALE UPPER TROUGH DEVELOPS ACROSS THE REGION AND
SURFACE COLD FRONT EVENTUALLY MOVES THROUGH THE AREA LATE MONDAY.
GUIDANCE IN GENERAL AGREEMENT IN THUNDERSTORM POTENTIAL INCREASING
MAINLY ACROSS NORTH CENTRAL IL LATE SUNDAY NIGHT...THEN SPREADING
ACROSS THE REMAINDER OF THE CWA MONDAY/MONDAY NIGHT. INCREASED DEEP
SHEAR WITH STRONGER JET ALOFT...AND INSTABILITY FED BY POOLING OF
HIGHER DEW POINT AIR AHEAD OF COLD FRONT INDICATES THE POTENTIAL FOR
SEVERE STORMS FOR THE FORECAST AREA MONDAY...AS DEPICTED IN SPC DAY 3
OUTLOOK.
GUIDANCE WAS SIGNIFICANTLY COOL WITH TEMPS FRIDAY...AND IT APPEARS
THIS BIAS CONTINUES TODAY...SUNDAY AND POTENTIALLY MONDAY. HAVE GONE
ABOVE MOS NUMBERS BASED ON LOCAL 850 HPA TEMP CLIMO...THOUGH
INCREASED CLOUD COVER MAY COMPLICATE THINGS A BIT. SUNDAY AND MONDAY
HAVE THE POTENTIAL TO BE VERY WARM...LOW 90S IN SPOTS...DEPENDENT ON
AMOUNT OF CLOUDS.
ONCE COLD FRONT CLEARS AREA MONDAY NIGHT...A GRADUAL COOLING TREND
SETS UP FOR THE MID/LATE WEEK PERIOD. NORTHWEST FLOW WITH A COUPLE
OF SHORT WAVE IMPULSES NOTED TUES-WED WHICH MAY PRODUCE A FEW
SCATTERED AFTERNOON SHOWERS THOSE DAYS...BUT HIGH PRESSURE BUILDS IN
BY THE 4TH WHICH SHOULD ALLOW FOR PLEASANT HOLIDAY WEATHER WITH
TEMPS NEAR 80 AND 70S NEAR THE LAKE. LONGER RANGE MODEL SOLUTIONS
INDICATE A RETURN OF WARMER WEATHER OVER THE HOLIDAY WEEKEND...JUST
BEYOND THE CURRENT FORECAST PERIOD.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* ISOLATED SHRA/TSRA MID MORNING THRU LATE AFTERNOON.
* GUSTY SOUTHERLY WINDS MID MORNING THRU SUNSET.
* CHANCE OF SHRA/TSRA SUNDAY MORNING. CMS/BMD
//DISCUSSION...UPDATED 12Z...
A WEAK UPPER WAVE WILL MOVE ACROSS THE AREA LATER THIS MORNING
INTO THIS AFTERNOON AND IS EXPECTED TO AID TSRA DEVELOPMENT BUT
TIMING AND COVERAGE REMAIN UNCERTAIN...THOUGH HI RES/SHORT TERM
GUIDANCE SUGGEST SHRA DEVELOPMENT BY MID MORNING. WITH DEWPOINTS
IN THE MID/UPPER 60S...AS TEMPS WARM DURING THE MORNING...SOME
ISOLATED ACTIVITY IS CERTAINLY POSSIBLE. BUT BEST TIMING FOR TSRA
APPEARS TO BE IN THE EARLY/MID AFTERNOON AS THE UPPER WAVE
ARRIVES. AS THIS WAVE DEPARTS LATER THIS AFTERNOON...EXPECT SOME
DECREASE IN COVERAGE BUT ISOLATED ACTIVITY MAY CONTINUE THROUGH
SUNSET.
ADDITIONAL TSRA EXPECTED TO DEVELOP FURTHER WEST TODAY AND THEN
MOVE EAST TONIGHT AND POTENTIALLY ACROSS THE TERMINALS EARLY/MID
SUNDAY MORNING. CONFIDENCE IS FAIRLY LOW REGARDING HOW MUCH OF
THIS ACTIVITY WILL REACH THE TERMINALS.
SOUTH/SOUTHEAST WINDS AROUND 10KTS WILL INCREASE INTO THE 12-16KT
RANGE THROUGH LATE MORNING WITH HIGHER GUSTS INTO THE 20KT RANGE
AND WINDS SHOULD TURN MORE SOUTHERLY BY LATE MORNING. CMS
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* MEDIUM FOR ISOLATED SHRA/TSRA MID MORNING THRU LATE
AFTERNOON...LOW FOR COVERAGE AND TIMING.
* MEDIUM FOR WINDS THRU THE PERIOD.
* LOW FOR SHRA/TSRA SUNDAY MORNING. CMS/BMD
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
* SUNDAY NIGHT...CHANCE OF TSRA LATE.
* MONDAY...TSRA LIKELY.
* TUESDAY AND WEDNESDAY...SLIGHT CHANCE SHRA.
* THURSDAY AND FRIDAY...DRY/VFR.
&&
.MARINE...
240 AM...HIGH PRESSURE OVER NEW ENGLAND WILL SLOWLY DRIFT OFF THE
EAST COAST SUNDAY AND SUNDAY NIGHT. A LARGE TROUGH OF LOW PRESSURE
EXTENDING FROM MANITOBA TO KANSAS WILL SLOWLY DRIFT NORTH FORMING
A DEEP AREA OF LOW PRESSURE OVER SOUTHERN MANITOBA ON SUNDAY. THE
GRADIENT WILL SLOWLY TIGHTEN AS THIS OCCURS WITH SOUTHERLY WINDS
INCREASING INTO THE 15-25KT RANGE OVER LAKE MICHIGAN. THE LOW WILL
SLOWLY MOVE NORTHEAST REACHING JAMES BAY TUESDAY WITH A TRAILING
COLD FRONT MOVING ACROSS THE LAKE MONDAY NIGHT OR TUESDAY MORNING.
THE STRONGEST WINDS WILL LIKELY BE AHEAD OF THIS COLD FRONT...ON
MONDAY. WINDS THEN SHIFT WESTERLY BEHIND THE FRONT. THE STRONGER
WINDS ARE EXPECTED TO PREVENT ANY WIDESPREAD DENSE FOG OVER THE
LAKE BUT WILL MAINTAIN CURRENT HAZE/PATCHY DENSE FOG WORDING. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
905 AM CDT SAT JUN 28 2014
.DISCUSSION...
355 AM CDT
MAIN FORECAST CHALLENGES ARE THUNDERSTORM CHANCES AND TEMPERATURES
WITH WARM/HUMID CONDITIONS THROUGH MONDAY...THEN GRADUAL COOLING
TUESDAY-WEDNESDAY. HIGH PRESSURE LATE IN THE WEEK SHOULD MAKE FOR
NICE WEATHER FOR THE JULY 4TH HOLIDAY...WITH SIGNS OF WARMER WEATHER
RETURNING OVER THE HOLIDAY WEEKEND.
RATHER INDISTINCT SURFACE WARM FRONT WAS ANALYZED FROM THE UPPER
MIDWEST...SOUTHEAST ACROSS ILLINOIS AND INTO CENTRAL INDIANA EARLY
THIS MORNING. THIS WARM FRONT WILL CONTINUE TO LIFT ACROSS THE
FORECAST AREA THIS MORNING...WITHIN BROAD SOUTHERLY RETURN FLOW IN
LOW LEVELS AHEAD OF LOW PRESSURE OVER THE PLAINS. WARM/MOIST AIR
MASS CHARACTERIZED BY TEMPS IN THE LOW-MID 70S AND DEW POINTS OF
65-70 IS EXPECTED TO DESTABILIZE AFTER SUNRISE...WITH FORECAST
SOUNDINGS FROM 06Z RAP DEPICTING LITTLE/NO CAP AND MLCAPE
APPROACHING 1000 J/KG BY MID/LATE MORNING. SIMILAR TO THE PAST FEW
DAYS...WEAK FLOW ALOFT AND LACK OF STRONG LOW LEVEL CONVERGENT FOCUS
SUGGESTS ONLY ISOLATED TO SCATTERED COVERAGE OF SHOWERS AND
THUNDERSTORMS TODAY. WEAK MID-LEVEL SHORT WAVE IS NOTED OVER THE
REGION THIS MORNING HOWEVER...WITH SOME PERSISTENT WEAK RADAR
RETURNS VICINITY KBMI EVIDENCE OF VORT. PRESENCE OF THIS WEAK WAVE
AND EARLY DESTABILIZATION IS EXPECTED TO RESULT IN ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING BY LATE MORNING WITH
EASTERN PORTIONS OF THE CWA PERHAPS MORE FAVORED GIVEN TRACK OF
VORT. STEEP MID-LEVEL LAPSE RATES/EML SEEN IN UPSTREAM TOP/SGF 00Z
SOUNDINGS WILL APPROACH LATER IN THE DAY PER FORECAST SOUNDINGS...
WHICH MAY PROVIDE A BIT MORE CAPPING BY AFTERNOON WHICH ALONG WITH
MID-LEVEL WAVE SLOWLY LIFTING NORTH OF THE AREA MAY LIMIT COVERAGE
AT THAT TIME...THOUGH DIURNAL PEAK HEATING WILL LIKELY ALLOW FOR A
FEW SCATTERED STORMS TO CONTINUE. LOCALLY HEAVY RAINFALL WILL REMAIN
A POSSIBILITY WITH ANY STORMS THAT DEVELOP...WITH PRECIPITABLE WATER
VALUES IN EXCESS OF 1.7 INCHES.
A GREATER CHANCE OF MORE ORGANIZED THUNDERSTORMS IS EXPECTED LATER
TONIGHT INTO SUNDAY...AS A MORE AMPLIFIED SHORT WAVE PROPAGATES FROM
THE PLAINS TO THE UPPER MIDWEST AND NORTHERN GREAT LAKES THROUGH
SUNDAY MORNING. MODEST ORGANIZED HEIGHT FALLS WITH THIS FEATURE AS
WELL AS MODESTLY INCREASED MOISTURE TRANSPORT ON 30-35 KT SOUTHWEST
LOW LEVEL JET SHOULD HELP OFFSET POOR DIURNAL TIMING...THOUGH HAVE
GENERALLY GONE WITH LOWER RANGE OF GUIDANCE POPS WITH HIGH CHANCE/50
PERCENT RANGE DURING THE LATE NIGHT/SUNDAY MORNING PERIOD. HAVE
MAINTAINED CHANCE POPS INTO SUNDAY AFTERNOON MAINLY SOUTHEAST OF A
PONTIAC TO GARY LINE...AND LOWERED POPS TO A SLIGHT 20 PERCENT
NORTHWEST OF IT. LARGE SCALE FORCING DECREASES BEHIND DEPARTING
SHORT WAVE TROUGH AXIS SUNDAY AFTERNOON...THOUGH NAM FORECAST
SOUNDINGS MAINTAIN CONSIDERABLE MLCAPE WITH LITTLE/NO CAP ACROSS THE
REGION. GFS AND LOCAL WRF RUN DEPICT A STRONGER CAP WHICH APPEARS A
BIT MORE LIKELY GIVEN HEIGHT RISES...SUPPORTING LOW/NIL POPS ACROSS
NORTHERN IL FOR THE AFTERNOON/EVENING HOURS. WESTERLY FLOW ALOFT
STRENGTHENS ACROSS PLAINS/UPPER MIDWEST BY SUNDAY NIGHT...WITH THE
RESULTING INCREASE IN DEEP LAYER WIND SHEAR SUPPORTING DEVELOPMENT
OF POTENTIALLY SEVERE STORMS ACROSS AREAS TO OUR WEST. OUR CHANCE OF
THUNDERSTORMS LOOKS TO INCREASE ONCE AGAIN LATE SUNDAY NIGHT INTO
MONDAY AS LARGE-SCALE UPPER TROUGH DEVELOPS ACROSS THE REGION AND
SURFACE COLD FRONT EVENTUALLY MOVES THROUGH THE AREA LATE MONDAY.
GUIDANCE IN GENERAL AGREEMENT IN THUNDERSTORM POTENTIAL INCREASING
MAINLY ACROSS NORTH CENTRAL IL LATE SUNDAY NIGHT...THEN SPREADING
ACROSS THE REMAINDER OF THE CWA MONDAY/MONDAY NIGHT. INCREASED DEEP
SHEAR WITH STRONGER JET ALOFT...AND INSTABILITY FED BY POOLING OF
HIGHER DEW POINT AIR AHEAD OF COLD FRONT INDICATES THE POTENTIAL FOR
SEVERE STORMS FOR THE FORECAST AREA MONDAY...AS DEPICTED IN SPC DAY 3
OUTLOOK.
GUIDANCE WAS SIGNIFICANTLY COOL WITH TEMPS FRIDAY...AND IT APPEARS
THIS BIAS CONTINUES TODAY...SUNDAY AND POTENTIALLY MONDAY. HAVE GONE
ABOVE MOS NUMBERS BASED ON LOCAL 850 HPA TEMP CLIMO...THOUGH
INCREASED CLOUD COVER MAY COMPLICATE THINGS A BIT. SUNDAY AND MONDAY
HAVE THE POTENTIAL TO BE VERY WARM...LOW 90S IN SPOTS...DEPENDENT ON
AMOUNT OF CLOUDS.
ONCE COLD FRONT CLEARS AREA MONDAY NIGHT...A GRADUAL COOLING TREND
SETS UP FOR THE MID/LATE WEEK PERIOD. NORTHWEST FLOW WITH A COUPLE
OF SHORT WAVE IMPULSES NOTED TUES-WED WHICH MAY PRODUCE A FEW
SCATTERED AFTERNOON SHOWERS THOSE DAYS...BUT HIGH PRESSURE BUILDS IN
BY THE 4TH WHICH SHOULD ALLOW FOR PLEASANT HOLIDAY WEATHER WITH
TEMPS NEAR 80 AND 70S NEAR THE LAKE. LONGER RANGE MODEL SOLUTIONS
INDICATE A RETURN OF WARMER WEATHER OVER THE HOLIDAY WEEKEND...JUST
BEYOND THE CURRENT FORECAST PERIOD.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* ISOLATED SHRA/TSRA MID MORNING THRU LATE AFTERNOON.
* GUSTY SOUTHERLY WINDS MID MORNING THRU SUNSET.
* CHANCE OF SHRA/TSRA SUNDAY MORNING. CMS/BMD
//DISCUSSION...UPDATED 12Z...
A WEAK UPPER WAVE WILL MOVE ACROSS THE AREA LATER THIS MORNING
INTO THIS AFTERNOON AND IS EXPECTED TO AID TSRA DEVELOPMENT BUT
TIMING AND COVERAGE REMAIN UNCERTAIN...THOUGH HI RES/SHORT TERM
GUIDANCE SUGGEST SHRA DEVELOPMENT BY MID MORNING. WITH DEWPOINTS
IN THE MID/UPPER 60S...AS TEMPS WARM DURING THE MORNING...SOME
ISOLATED ACTIVITY IS CERTAINLY POSSIBLE. BUT BEST TIMING FOR TSRA
APPEARS TO BE IN THE EARLY/MID AFTERNOON AS THE UPPER WAVE
ARRIVES. AS THIS WAVE DEPARTS LATER THIS AFTERNOON...EXPECT SOME
DECREASE IN COVERAGE BUT ISOLATED ACTIVITY MAY CONTINUE THROUGH
SUNSET.
ADDITIONAL TSRA EXPECTED TO DEVELOP FURTHER WEST TODAY AND THEN
MOVE EAST TONIGHT AND POTENTIALLY ACROSS THE TERMINALS EARLY/MID
SUNDAY MORNING. CONFIDENCE IS FAIRLY LOW REGARDING HOW MUCH OF
THIS ACTIVITY WILL REACH THE TERMINALS.
SOUTH/SOUTHEAST WINDS AROUND 10KTS WILL INCREASE INTO THE 12-16KT
RANGE THROUGH LATE MORNING WITH HIGHER GUSTS INTO THE 20KT RANGE
AND WINDS SHOULD TURN MORE SOUTHERLY BY LATE MORNING. CMS
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* MEDIUM FOR ISOLATED SHRA/TSRA MID MORNING THRU LATE
AFTERNOON...LOW FOR COVERAGE AND TIMING.
* MEDIUM FOR WINDS THRU THE PERIOD.
* LOW FOR SHRA/TSRA SUNDAY MORNING. CMS/BMD
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
* SUNDAY NIGHT...CHANCE OF TSRA LATE.
* MONDAY...TSRA LIKELY.
* TUESDAY AND WEDNESDAY...SLIGHT CHANCE SHRA.
* THURSDAY AND FRIDAY...DRY/VFR.
&&
.MARINE...
240 AM...HIGH PRESSURE OVER NEW ENGLAND WILL SLOWLY DRIFT OFF THE
EAST COAST SUNDAY AND SUNDAY NIGHT. A LARGE TROUGH OF LOW PRESSURE
EXTENDING FROM MANITOBA TO KANSAS WILL SLOWLY DRIFT NORTH FORMING
A DEEP AREA OF LOW PRESSURE OVER SOUTHERN MANITOBA ON SUNDAY. THE
GRADIENT WILL SLOWLY TIGHTEN AS THIS OCCURS WITH SOUTHERLY WINDS
INCREASING INTO THE 15-25KT RANGE OVER LAKE MICHIGAN. THE LOW WILL
SLOWLY MOVE NORTHEAST REACHING JAMES BAY TUESDAY WITH A TRAILING
COLD FRONT MOVING ACROSS THE LAKE MONDAY NIGHT OR TUESDAY MORNING.
THE STRONGEST WINDS WILL LIKELY BE AHEAD OF THIS COLD FRONT...ON
MONDAY. WINDS THEN SHIFT WESTERLY BEHIND THE FRONT. THE STRONGER
WINDS ARE EXPECTED TO PREVENT ANY WIDESPREAD DENSE FOG OVER THE
LAKE BUT WILL MAINTAIN CURRENT HAZE/PATCHY DENSE FOG WORDING. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
635 AM CDT SAT JUN 28 2014
.DISCUSSION...
355 AM CDT
MAIN FORECAST CHALLENGES ARE THUNDERSTORM CHANCES AND TEMPERATURES
WITH WARM/HUMID CONDITIONS THROUGH MONDAY...THEN GRADUAL COOLING
TUESDAY-WEDNESDAY. HIGH PRESSURE LATE IN THE WEEK SHOULD MAKE FOR
NICE WEATHER FOR THE JULY 4TH HOLIDAY...WITH SIGNS OF WARMER WEATHER
RETURNING OVER THE HOLIDAY WEEKEND.
RATHER INDISTINCT SURFACE WARM FRONT WAS ANALYZED FROM THE UPPER
MIDWEST...SOUTHEAST ACROSS ILLINOIS AND INTO CENTRAL INDIANA EARLY
THIS MORNING. THIS WARM FRONT WILL CONTINUE TO LIFT ACROSS THE
FORECAST AREA THIS MORNING...WITHIN BROAD SOUTHERLY RETURN FLOW IN
LOW LEVELS AHEAD OF LOW PRESSURE OVER THE PLAINS. WARM/MOIST AIR
MASS CHARACTERIZED BY TEMPS IN THE LOW-MID 70S AND DEW POINTS OF
65-70 IS EXPECTED TO DESTABILIZE AFTER SUNRISE...WITH FORECAST
SOUNDINGS FROM 06Z RAP DEPICTING LITTLE/NO CAP AND MLCAPE
APPROACHING 1000 J/KG BY MID/LATE MORNING. SIMILAR TO THE PAST FEW
DAYS...WEAK FLOW ALOFT AND LACK OF STRONG LOW LEVEL CONVERGENT FOCUS
SUGGESTS ONLY ISOLATED TO SCATTERED COVERAGE OF SHOWERS AND
THUNDERSTORMS TODAY. WEAK MID-LEVEL SHORT WAVE IS NOTED OVER THE
REGION THIS MORNING HOWEVER...WITH SOME PERSISTENT WEAK RADAR
RETURNS VICINITY KBMI EVIDENCE OF VORT. PRESENCE OF THIS WEAK WAVE
AND EARLY DESTABILIZATION IS EXPECTED TO RESULT IN ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING BY LATE MORNING WITH
EASTERN PORTIONS OF THE CWA PERHAPS MORE FAVORED GIVEN TRACK OF
VORT. STEEP MID-LEVEL LAPSE RATES/EML SEEN IN UPSTREAM TOP/SGF 00Z
SOUNDINGS WILL APPROACH LATER IN THE DAY PER FORECAST SOUNDINGS...
WHICH MAY PROVIDE A BIT MORE CAPPING BY AFTERNOON WHICH ALONG WITH
MID-LEVEL WAVE SLOWLY LIFTING NORTH OF THE AREA MAY LIMIT COVERAGE
AT THAT TIME...THOUGH DIURNAL PEAK HEATING WILL LIKELY ALLOW FOR A
FEW SCATTERED STORMS TO CONTINUE. LOCALLY HEAVY RAINFALL WILL REMAIN
A POSSIBILITY WITH ANY STORMS THAT DEVELOP...WITH PRECIPITABLE WATER
VALUES IN EXCESS OF 1.7 INCHES.
A GREATER CHANCE OF MORE ORGANIZED THUNDERSTORMS IS EXPECTED LATER
TONIGHT INTO SUNDAY...AS A MORE AMPLIFIED SHORT WAVE PROPAGATES FROM
THE PLAINS TO THE UPPER MIDWEST AND NORTHERN GREAT LAKES THROUGH
SUNDAY MORNING. MODEST ORGANIZED HEIGHT FALLS WITH THIS FEATURE AS
WELL AS MODESTLY INCREASED MOISTURE TRANSPORT ON 30-35 KT SOUTHWEST
LOW LEVEL JET SHOULD HELP OFFSET POOR DIURNAL TIMING...THOUGH HAVE
GENERALLY GONE WITH LOWER RANGE OF GUIDANCE POPS WITH HIGH CHANCE/50
PERCENT RANGE DURING THE LATE NIGHT/SUNDAY MORNING PERIOD. HAVE
MAINTAINED CHANCE POPS INTO SUNDAY AFTERNOON MAINLY SOUTHEAST OF A
PONTIAC TO GARY LINE...AND LOWERED POPS TO A SLIGHT 20 PERCENT
NORTHWEST OF IT. LARGE SCALE FORCING DECREASES BEHIND DEPARTING
SHORT WAVE TROUGH AXIS SUNDAY AFTERNOON...THOUGH NAM FORECAST
SOUNDINGS MAINTAIN CONSIDERABLE MLCAPE WITH LITTLE/NO CAP ACROSS THE
REGION. GFS AND LOCAL WRF RUN DEPICT A STRONGER CAP WHICH APPEARS A
BIT MORE LIKELY GIVEN HEIGHT RISES...SUPPORTING LOW/NIL POPS ACROSS
NORTHERN IL FOR THE AFTERNOON/EVENING HOURS. WESTERLY FLOW ALOFT
STRENGTHENS ACROSS PLAINS/UPPER MIDWEST BY SUNDAY NIGHT...WITH THE
RESULTING INCREASE IN DEEP LAYER WIND SHEAR SUPPORTING DEVELOPMENT
OF POTENTIALLY SEVERE STORMS ACROSS AREAS TO OUR WEST. OUR CHANCE OF
THUNDERSTORMS LOOKS TO INCREASE ONCE AGAIN LATE SUNDAY NIGHT INTO
MONDAY AS LARGE-SCALE UPPER TROUGH DEVELOPS ACROSS THE REGION AND
SURFACE COLD FRONT EVENTUALLY MOVES THROUGH THE AREA LATE MONDAY.
GUIDANCE IN GENERAL AGREEMENT IN THUNDERSTORM POTENTIAL INCREASING
MAINLY ACROSS NORTH CENTRAL IL LATE SUNDAY NIGHT...THEN SPREADING
ACROSS THE REMAINDER OF THE CWA MONDAY/MONDAY NIGHT. INCREASED DEEP
SHEAR WITH STRONGER JET ALOFT...AND INSTABILITY FED BY POOLING OF
HIGHER DEW POINT AIR AHEAD OF COLD FRONT INDICATES THE POTENTIAL FOR
SEVERE STORMS FOR THE FORECAST AREA MONDAY...AS DEPICTED IN SPC DAY 3
OUTLOOK.
GUIDANCE WAS SIGNIFICANTLY COOL WITH TEMPS FRIDAY...AND IT APPEARS
THIS BIAS CONTINUES TODAY...SUNDAY AND POTENTIALLY MONDAY. HAVE GONE
ABOVE MOS NUMBERS BASED ON LOCAL 850 HPA TEMP CLIMO...THOUGH
INCREASED CLOUD COVER MAY COMPLICATE THINGS A BIT. SUNDAY AND MONDAY
HAVE THE POTENTIAL TO BE VERY WARM...LOW 90S IN SPOTS...DEPENDENT ON
AMOUNT OF CLOUDS.
ONCE COLD FRONT CLEARS AREA MONDAY NIGHT...A GRADUAL COOLING TREND
SETS UP FOR THE MID/LATE WEEK PERIOD. NORTHWEST FLOW WITH A COUPLE
OF SHORT WAVE IMPULSES NOTED TUES-WED WHICH MAY PRODUCE A FEW
SCATTERED AFTERNOON SHOWERS THOSE DAYS...BUT HIGH PRESSURE BUILDS IN
BY THE 4TH WHICH SHOULD ALLOW FOR PLEASANT HOLIDAY WEATHER WITH
TEMPS NEAR 80 AND 70S NEAR THE LAKE. LONGER RANGE MODEL SOLUTIONS
INDICATE A RETURN OF WARMER WEATHER OVER THE HOLIDAY WEEKEND...JUST
BEYOND THE CURRENT FORECAST PERIOD.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* ISOLATED SHRA/TSRA MID MORNING THRU LATE AFTERNOON.
* GUSTY SOUTHERLY WINDS MID MORNING THRU SUNSET.
* CHANCE OF SHRA/TSRA SUNDAY MORNING. CMS
//DISCUSSION...UPDATED 12Z...
A WEAK UPPER WAVE WILL MOVE ACROSS THE AREA LATER THIS MORNING
INTO THIS AFTERNOON AND IS EXPECTED TO AID TSRA DEVELOPMENT BUT
TIMING AND COVERAGE REMAIN UNCERTAIN...THOUGH HI RES/SHORT TERM
GUIDANCE SUGGEST SHRA DEVELOPEMENT BY MID MORNING. WITH DEWPOINTS
IN THE MID/UPPER 60S...AS TEMPS WARM DURING THE MORNING...SOME
ISOLATED ACTIVITY IS CERTAINLY POSSIBLE. BUT BEST TIMING FOR TSRA
APPEARS TO BE IN THE EARLY/MID AFTERNOON AS THE UPPER WAVE
ARRIVES. AS THIS WAVE DEPARTS LATER THIS AFTERNOON...EXPECT SOME
DECREASE IN COVERAGE BUT ISOLATED ACTIVITY MAY CONTINUE THROUGH
SUNSET.
ADDITIONAL TSRA EXPECTED TO DEVELOP FURTHER WEST TODAY AND THEN
MOVE EAST TONIGHT AND POTENTIALLY ACROSS THE TERMINALS EARLY/MID
SUNDAY MORNING. CONFIDENCE IS FAIRLY LOW REGARDING HOW MUCH OF
THIS ACTIVITY WILL REACH THE TERMINALS.
SOUTH/SOUTHEAST WINDS AROUND 10KTS WILL INCREASE INTO THE 12-16KT
RANGE THROUGH LATE MORNING WITH HIGHER GUSTS INTO THE 20KT RANGE
AND WINDS SHOULD TURN MORE SOUTHERLY BY LATE MORNING. CMS
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* MEDIUM FOR ISOLATED SHRA/TSRA MID MORNING THRU LATE
AFTERNOON...LOW FOR COVERAGE AND TIMING.
* MEDIUM FOR WINDS THRU THE PERIOD.
* LOW FOR SHRA/TSRA SUNDAY MORNING. CMS
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
* SUNDAY NIGHT...CHANCE OF TSRA LATE.
* MONDAY...TSRA LIKELY.
* TUESDAY AND WEDNESDAY...SLIGHT CHANCE SHRA.
* THURSDAY AND FRIDAY...DRY/VFR.
&&
.MARINE...
240 AM...HIGH PRESSURE OVER NEW ENGLAND WILL SLOWLY DRIFT OFF THE
EAST COAST SUNDAY AND SUNDAY NIGHT. A LARGE TROUGH OF LOW PRESSURE
EXTENDING FROM MANITOBA TO KANSAS WILL SLOWLY DRIFT NORTH FORMING
A DEEP AREA OF LOW PRESSURE OVER SOUTHERN MANITOBA ON SUNDAY. THE
GRADIENT WILL SLOWLY TIGHTEN AS THIS OCCURS WITH SOUTHERLY WINDS
INCREASING INTO THE 15-25KT RANGE OVER LAKE MICHIGAN. THE LOW WILL
SLOWLY MOVE NORTHEAST REACHING JAMES BAY TUESDAY WITH A TRAILING
COLD FRONT MOVING ACROSS THE LAKE MONDAY NIGHT OR TUESDAY MORNING.
THE STRONGEST WINDS WILL LIKELY BE AHEAD OF THIS COLD FRONT...ON
MONDAY. WINDS THEN SHIFT WESTERLY BEHIND THE FRONT. THE STRONGER
WINDS ARE EXPECTED TO PREVENT ANY WIDESPREAD DENSE FOG OVER THE
LAKE BUT WILL MAINTAIN CURRENT HAZE/PATCHY DENSE FOG WORDING. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
402 AM CDT SAT JUN 28 2014
.DISCUSSION...
355 AM CDT
MAIN FORECAST CHALLENGES ARE THUNDERSTORM CHANCES AND TEMPERATURES
WITH WARM/HUMID CONDITIONS THROUGH MONDAY...THEN GRADUAL COOLING
TUESDAY-WEDNESDAY. HIGH PRESSURE LATE IN THE WEEK SHOULD MAKE FOR
NICE WEATHER FOR THE JULY 4TH HOLIDAY...WITH SIGNS OF WARMER WEATHER
RETURNING OVER THE HOLIDAY WEEKEND.
RATHER INDISTINCT SURFACE WARM FRONT WAS ANALYZED FROM THE UPPER
MIDWEST...SOUTHEAST ACROSS ILLINOIS AND INTO CENTRAL INDIANA EARLY
THIS MORNING. THIS WARM FRONT WILL CONTINUE TO LIFT ACROSS THE
FORECAST AREA THIS MORNING...WITHIN BROAD SOUTHERLY RETURN FLOW IN
LOW LEVELS AHEAD OF LOW PRESSURE OVER THE PLAINS. WARM/MOIST AIR
MASS CHARACTERIZED BY TEMPS IN THE LOW-MID 70S AND DEW POINTS OF
65-70 IS EXPECTED TO DESTABILIZE AFTER SUNRISE...WITH FORECAST
SOUNDINGS FROM 06Z RAP DEPICTING LITTLE/NO CAP AND MLCAPE
APPROACHING 1000 J/KG BY MID/LATE MORNING. SIMILAR TO THE PAST FEW
DAYS...WEAK FLOW ALOFT AND LACK OF STRONG LOW LEVEL CONVERGENT FOCUS
SUGGESTS ONLY ISOLATED TO SCATTERED COVERAGE OF SHOWERS AND
THUNDERSTORMS TODAY. WEAK MID-LEVEL SHORT WAVE IS NOTED OVER THE
REGION THIS MORNING HOWEVER...WITH SOME PERSISTENT WEAK RADAR
RETURNS VICINITY KBMI EVIDENCE OF VORT. PRESENCE OF THIS WEAK WAVE
AND EARLY DESTABILIZATION IS EXPECTED TO RESULT IN ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING BY LATE MORNING WITH
EASTERN PORTIONS OF THE CWA PERHAPS MORE FAVORED GIVEN TRACK OF
VORT. STEEP MID-LEVEL LAPSE RATES/EML SEEN IN UPSTREAM TOP/SGF 00Z
SOUNDINGS WILL APPROACH LATER IN THE DAY PER FORECAST SOUNDINGS...
WHICH MAY PROVIDE A BIT MORE CAPPING BY AFTERNOON WHICH ALONG WITH
MID-LEVEL WAVE SLOWLY LIFTING NORTH OF THE AREA MAY LIMIT COVERAGE
AT THAT TIME...THOUGH DIURNAL PEAK HEATING WILL LIKELY ALLOW FOR A
FEW SCATTERED STORMS TO CONTINUE. LOCALLY HEAVY RAINFALL WILL REMAIN
A POSSIBILITY WITH ANY STORMS THAT DEVELOP...WITH PRECIPITABLE WATER
VALUES IN EXCESS OF 1.7 INCHES.
A GREATER CHANCE OF MORE ORGANIZED THUNDERSTORMS IS EXPECTED LATER
TONIGHT INTO SUNDAY...AS A MORE AMPLIFIED SHORT WAVE PROPAGATES FROM
THE PLAINS TO THE UPPER MIDWEST AND NORTHERN GREAT LAKES THROUGH
SUNDAY MORNING. MODEST ORGANIZED HEIGHT FALLS WITH THIS FEATURE AS
WELL AS MODESTLY INCREASED MOISTURE TRANSPORT ON 30-35 KT SOUTHWEST
LOW LEVEL JET SHOULD HELP OFFSET POOR DIURNAL TIMING...THOUGH HAVE
GENERALLY GONE WITH LOWER RANGE OF GUIDANCE POPS WITH HIGH CHANCE/50
PERCENT RANGE DURING THE LATE NIGHT/SUNDAY MORNING PERIOD. HAVE
MAINTAINED CHANCE POPS INTO SUNDAY AFTERNOON MAINLY SOUTHEAST OF A
PONTIAC TO GARY LINE...AND LOWERED POPS TO A SLIGHT 20 PERCENT
NORTHWEST OF IT. LARGE SCALE FORCING DECREASES BEHIND DEPARTING
SHORT WAVE TROUGH AXIS SUNDAY AFTERNOON...THOUGH NAM FORECAST
SOUNDINGS MAINTAIN CONSIDERABLE MLCAPE WITH LITTLE/NO CAP ACROSS THE
REGION. GFS AND LOCAL WRF RUN DEPICT A STRONGER CAP WHICH APPEARS A
BIT MORE LIKELY GIVEN HEIGHT RISES...SUPPORTING LOW/NIL POPS ACROSS
NORTHERN IL FOR THE AFTERNOON/EVENING HOURS. WESTERLY FLOW ALOFT
STRENGTHENS ACROSS PLAINS/UPPER MIDWEST BY SUNDAY NIGHT...WITH THE
RESULTING INCREASE IN DEEP LAYER WIND SHEAR SUPPORTING DEVELOPMENT
OF POTENTIALLY SEVERE STORMS ACROSS AREAS TO OUR WEST. OUR CHANCE OF
THUNDERSTORMS LOOKS TO INCREASE ONCE AGAIN LATE SUNDAY NIGHT INTO
MONDAY AS LARGE-SCALE UPPER TROUGH DEVELOPS ACROSS THE REGION AND
SURFACE COLD FRONT EVENTUALLY MOVES THROUGH THE AREA LATE MONDAY.
GUIDANCE IN GENERAL AGREEMENT IN THUNDERSTORM POTENTIAL INCREASING
MAINLY ACROSS NORTH CENTRAL IL LATE SUNDAY NIGHT...THEN SPREADING
ACROSS THE REMAINDER OF THE CWA MONDAY/MONDAY NIGHT. INCREASED DEEP
SHEAR WITH STRONGER JET ALOFT...AND INSTABILITY FED BY POOLING OF
HIGHER DEW POINT AIR AHEAD OF COLD FRONT INDICATES THE POTENTIAL FOR
SEVERE STORMS FOR THE FORECAST AREA MONDAY...AS DEPICTED IN SPC DAY 3
OUTLOOK.
GUIDANCE WAS SIGNIFICANTLY COOL WITH TEMPS FRIDAY...AND IT APPEARS
THIS BIAS CONTINUES TODAY...SUNDAY AND POTENTIALLY MONDAY. HAVE GONE
ABOVE MOS NUMBERS BASED ON LOCAL 850 HPA TEMP CLIMO...THOUGH
INCREASED CLOUD COVER MAY COMPLICATE THINGS A BIT. SUNDAY AND MONDAY
HAVE THE POTENTIAL TO BE VERY WARM...LOW 90S IN SPOTS...DEPENDENT ON
AMOUNT OF CLOUDS.
ONCE COLD FRONT CLEARS AREA MONDAY NIGHT...A GRADUAL COOLING TREND
SETS UP FOR THE MID/LATE WEEK PERIOD. NORTHWEST FLOW WITH A COUPLE
OF SHORT WAVE IMPULSES NOTED TUES-WED WHICH MAY PRODUCE A FEW
SCATTERED AFTERNOON SHOWERS THOSE DAYS...BUT HIGH PRESSURE BUILDS IN
BY THE 4TH WHICH SHOULD ALLOW FOR PLEASANT HOLIDAY WEATHER WITH
TEMPS NEAR 80 AND 70S NEAR THE LAKE. LONGER RANGE MODEL SOLUTIONS
INDICATE A RETURN OF WARMER WEATHER OVER THE HOLIDAY WEEKEND...JUST
BEYOND THE CURRENT FORECAST PERIOD.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* ISOLATED SHRA/TSRA MID MORNING THRU EARLY EVENING.
* GUSTY SOUTHERLY WINDS MID MORNING THRU SUNSET. CMS
//DISCUSSION...UPDATED 06Z...
MODELS SHOW A WEAK UPPER WAVE LIFTING NORTH ACROSS THE AREA LATER
THIS MORNING INTO THIS AFTERNOON WITH SOME DIFFERENCES REGARDING
TIMING AND LOCATION WITH SOME CONSENSUS FOR SHRA/TSRA ACTIVITY TO
DEVELOP SOUTH OF THE TERMINALS AND THEN LIFT NORTH ACROSS SOUTHERN
MI AND INDIANA. ITS POSSIBLE THAT ACTIVITY COULD BE DEVELOPING AS
EARLY AS 15Z-17Z BUT CONFIDENCE IS TOO LOW TO INCLUDE ANY
ADDITIONAL MENTION IN THIS FORECAST. A SLOWER MOVEMENT OF THIS
WAVE WOULD THEN ALLOW FOR LATER DEVELOPMENT...CLOSER TO THE TIMING
OF THE CURRENT PROB GROUP AND THEREFORE MADE NO CHANGES.
COMPLEX OF STORMS EXPECTED TO DEVELOP OVER THE PLAINS LATER TODAY
WILL CONTINUE EAST TONIGHT AND LIKELY BE DECAYING AS THEY MOVE
INTO NORTHWEST IL EARLY SUNDAY MORNING. CURRENT TIMING WOULD
SUGGEST ARRIVAL AFTER CURRENT END TIME OF THIS FORECAST...BUT
CONFIDENCE FOR ACTIVITY EARLY SUNDAY MORNING IS MEDIUM.
SOUTH/SOUTHEAST WINDS UNDER 10 KTS EARLY THIS MORNING WILL
INCREASE INTO THE 10-15KT RANGE BY MID MORNING WITH GUSTS INTO THE
UPPER TEEN RANGE DEVELOPING BY MID/LATE MORNING. POTENTIAL FOR
STRONGER GUSTS...ESPECIALLY ACROSS NORTHWEST IL AND RFD...BUT WILL
BE DEPENDENT ON CLOUD COVER/PRECIP COVERAGE. CMS
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* MEDIUM FOR ISOLATED SHRA/TSRA FROM MID MORNING THRU EARLY
EVENING...LOW FOR COVERAGE AND TIMING.
* MEDIUM FOR WINDS THRU THE PERIOD. CMS
//OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z...
SUNDAY THROUGH TUESDAY...CHC OF TSRA AND MVFR CIGS.
WEDNESDAY THROUGH THURSDAY...MAINLY VFR AND DRY.
BEACHLER
&&
.MARINE...
240 AM...HIGH PRESSURE OVER NEW ENGLAND WILL SLOWLY DRIFT OFF THE
EAST COAST SUNDAY AND SUNDAY NIGHT. A LARGE TROUGH OF LOW PRESSURE
EXTENDING FROM MANITOBA TO KANSAS WILL SLOWLY DRIFT NORTH FORMING
A DEEP AREA OF LOW PRESSURE OVER SOUTHERN MANITOBA ON SUNDAY. THE
GRADIENT WILL SLOWLY TIGHTEN AS THIS OCCURS WITH SOUTHERLY WINDS
INCREASING INTO THE 15-25KT RANGE OVER LAKE MICHIGAN. THE LOW WILL
SLOWLY MOVE NORTHEAST REACHING JAMES BAY TUESDAY WITH A TRAILING
COLD FRONT MOVING ACROSS THE LAKE MONDAY NIGHT OR TUESDAY MORNING.
THE STRONGEST WINDS WILL LIKELY BE AHEAD OF THIS COLD FRONT...ON
MONDAY. WINDS THEN SHIFT WESTERLY BEHIND THE FRONT. THE STRONGER
WINDS ARE EXPECTED TO PREVENT ANY WIDESPREAD DENSE FOG OVER THE
LAKE BUT WILL MAINTAIN CURRENT HAZE/PATCHY DENSE FOG WORDING. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
355 AM CDT SAT JUN 28 2014
.DISCUSSION...
355 AM CDT
MAIN FORECAST CHALLENGES ARE THUNDERSTORM CHANCES AND TEMPERATURES
WITH WARM/HUMID CONDITIONS THROUGH MONDAY...THEN GRADUAL COOLING
TUESDAY-WEDNESDAY. HIGH PRESSURE LATE IN THE WEEK SHOULD MAKE FOR
NICE WEATHER FOR THE JULY 4TH HOLIDAY...WITH SIGNS OF WARMER WEATHER
RETURNING OVER THE HOLIDAY WEEKEND.
RATHER INDISTINCT SURFACE WARM FRONT WAS ANALYZED FROM THE UPPER
MIDWEST...SOUTHEAST ACROSS ILLINOIS AND INTO CENTRAL INDIANA EARLY
THIS MORNING. THIS WARM FRONT WILL CONTINUE TO LIFT ACROSS THE
FORECAST AREA THIS MORNING...WITHIN BROAD SOUTHERLY RETURN FLOW IN
LOW LEVELS AHEAD OF LOW PRESSURE OVER THE PLAINS. WARM/MOIST AIR
MASS CHARACTERIZED BY TEMPS IN THE LOW-MID 70S AND DEW POINTS OF
65-70 IS EXPECTED TO DESTABILIZE AFTER SUNRISE...WITH FORECAST
SOUNDINGS FROM 06Z RAP DEPICTING LITTLE/NO CAP AND MLCAPE
APPROACHING 1000 J/KG BY MID/LATE MORNING. SIMILAR TO THE PAST FEW
DAYS...WEAK FLOW ALOFT AND LACK OF STRONG LOW LEVEL CONVERGENT FOCUS
SUGGESTS ONLY ISOLATED TO SCATTERED COVERAGE OF SHOWERS AND
THUNDERSTORMS TODAY. WEAK MID-LEVEL SHORT WAVE IS NOTED OVER THE
REGION THIS MORNING HOWEVER...WITH SOME PERSISTENT WEAK RADAR
RETURNS VICINITY KBMI EVIDENCE OF VORT. PRESENCE OF THIS WEAK WAVE
AND EARLY DESTABILIZATION IS EXPECTED TO RESULT IN ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING BY LATE MORNING WITH
EASTERN PORTIONS OF THE CWA PERHAPS MORE FAVORED GIVEN TRACK OF
VORT. STEEP MID-LEVEL LAPSE RATES/EML SEEN IN UPSTREAM TOP/SGF 00Z
SOUNDINGS WILL APPROACH LATER IN THE DAY PER FORECAST SOUNDINGS...
WHICH MAY PROVIDE A BIT MORE CAPPING BY AFTERNOON WHICH ALONG WITH
MID-LEVEL WAVE SLOWLY LIFTING NORTH OF THE AREA MAY LIMIT COVERAGE
AT THAT TIME...THOUGH DIURNAL PEAK HEATING WILL LIKELY ALLOW FOR A
FEW SCATTERED STORMS TO CONTINUE. LOCALLY HEAVY RAINFALL WILL REMAIN
A POSSIBILITY WITH ANY STORMS THAT DEVELOP...WITH PRECIPITABLE WATER
VALUES IN EXCESS OF 1.7 INCHES.
A GREATER CHANCE OF MORE ORGANIZED THUNDERSTORMS IS EXPECTED LATER
TONIGHT INTO SUNDAY...AS A MORE AMPLIFIED SHORT WAVE PROPAGATES FROM
THE PLAINS TO THE UPPER MIDWEST AND NORTHERN GREAT LAKES THROUGH
SUNDAY MORNING. MODEST ORGANIZED HEIGHT FALLS WITH THIS FEATURE AS
WELL AS MODESTLY INCREASED MOISTURE TRANSPORT ON 30-35 KT SOUTHWEST
LOW LEVEL JET SHOULD HELP OFFSET POOR DIURNAL TIMING...THOUGH HAVE
GENERALLY GONE WITH LOWER RANGE OF GUIDANCE POPS WITH HIGH CHANCE/50
PERCENT RANGE DURING THE LATE NIGHT/SUNDAY MORNING PERIOD. HAVE
MAINTAINED CHANCE POPS INTO SUNDAY AFTERNOON MAINLY SOUTHEAST OF A
PONTIAC TO GARY LINE...AND LOWERED POPS TO A SLIGHT 20 PERCENT
NORTHWEST OF IT. LARGE SCALE FORCING DECREASES BEHIND DEPARTING
SHORT WAVE TROUGH AXIS SUNDAY AFTERNOON...THOUGH NAM FORECAST
SOUNDINGS MAINTAIN CONSIDERABLE MLCAPE WITH LITTLE/NO CAP ACROSS THE
REGION. GFS AND LOCAL WRF RUN DEPICT A STRONGER CAP WHICH APPEARS A
BIT MORE LIKELY GIVEN HEIGHT RISES...SUPPORTING LOW/NIL POPS ACROSS
NORTHERN IL FOR THE AFTERNOON/EVENING HOURS. WESTERLY FLOW ALOFT
STRENGTHENS ACROSS PLAINS/UPPER MIDWEST BY SUNDAY NIGHT...WITH THE
RESULTING INCREASE IN DEEP LAYER WIND SHEAR SUPPORTING DEVELOPMENT
OF POTENTIALLY SEVERE STORMS ACROSS AREAS TO OUR WEST. OUR CHANCE OF
THUNDERSTORMS LOOKS TO INCREASE ONCE AGAIN LATE SUNDAY NIGHT INTO
MONDAY AS LARGE-SCALE UPPER TROUGH DEVELOPS ACROSS THE REGION AND
SURFACE COLD FRONT EVENTUALLY MOVES THROUGH THE AREA LATE MONDAY.
GUIDANCE IN GENERAL AGREEMENT IN THUNDERSTORM POTENTIAL INCREASING
MAINLY ACROSS NORTH CENTRAL IL LATE SUNDAY NIGHT...THEN SPREADING
ACROSS THE REMAINDER OF THE CWA MONDAY/MONDAY NIGHT. INCREASED DEEP
SHEAR WITH STRONGER JET ALOFT...AND INSTABILITY FED BY POOLING OF
HIGHER DEW POINT AIR AHEAD OF COLD FRONT INDICATES THE POTENTIAL FOR
SEVERE STORMS FOR THE FORECAST AREA MONDAY...AS DEPICTED IN SPC DAY 3
OUTLOOK.
GUIDANCE WAS SIGNIFICANTLY COOL WITH TEMPS FRIDAY...AND IT APPEARS
THIS BIAS CONTINUES TODAY...SUNDAY AND POTENTIALLY MONDAY. HAVE GONE
ABOVE MOS NUMBERS BASED ON LOCAL 850 HPA TEMP CLIMO...THOUGH
INCREASED CLOUD COVER MAY COMPLICATE THINGS A BIT. SUNDAY AND MONDAY
HAVE THE POTENTIAL TO BE VERY WARM...LOW 90S IN SPOTS...DEPENDENT ON
AMOUNT OF CLOUDS.
ONCE COLD FRONT CLEARS AREA MONDAY NIGHT...A GRADUAL COOLING TREND
SETS UP FOR THE MID/LATE WEEK PERIOD. NORTHWEST FLOW WITH A COUPLE
OF SHORT WAVE IMPULSES NOTED TUES-WED WHICH MAY PRODUCE A FEW
SCATTERED AFTERNOON SHOWERS THOSE DAYS...BUT HIGH PRESSURE BUILDS IN
BY THE 4TH WHICH SHOULD ALLOW FOR PLEASANT HOLIDAY WEATHER WITH
TEMPS NEAR 80 AND 70S NEAR THE LAKE. LONGER RANGE MODEL SOLUTIONS
INDICATE A RETURN OF WARMER WEATHER OVER THE HOLIDAY WEEKEND...JUST
BEYOND THE CURRENT FORECAST PERIOD.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* ISOLATED SHRA/TSRA MID MORNING THRU EARLY EVENING.
* GUSTY SOUTHERLY WINDS MID MORNING THRU SUNSET. CMS
//DISCUSSION...UPDATED 06Z...
MODELS SHOW A WEAK UPPER WAVE LIFTING NORTH ACROSS THE AREA LATER
THIS MORNING INTO THIS AFTERNOON WITH SOME DIFFERENCES REGARDING
TIMING AND LOCATION WITH SOME CONSENSUS FOR SHRA/TSRA ACTIVITY TO
DEVELOP SOUTH OF THE TERMINALS AND THEN LIFT NORTH ACROSS SOUTHERN
MI AND INDIANA. ITS POSSIBLE THAT ACTIVITY COULD BE DEVELOPING AS
EARLY AS 15Z-17Z BUT CONFIDENCE IS TOO LOW TO INCLUDE ANY
ADDITIONAL MENTION IN THIS FORECAST. A SLOWER MOVEMENT OF THIS
WAVE WOULD THEN ALLOW FOR LATER DEVELOPMENT...CLOSER TO THE TIMING
OF THE CURRENT PROB GROUP AND THEREFORE MADE NO CHANGES.
COMPLEX OF STORMS EXPECTED TO DEVELOP OVER THE PLAINS LATER TODAY
WILL CONTINUE EAST TONIGHT AND LIKELY BE DECAYING AS THEY MOVE
INTO NORTHWEST IL EARLY SUNDAY MORNING. CURRENT TIMING WOULD
SUGGEST ARRIVAL AFTER CURRENT END TIME OF THIS FORECAST...BUT
CONFIDENCE FOR ACTIVITY EARLY SUNDAY MORNING IS MEDIUM.
SOUTH/SOUTHEAST WINDS UNDER 10 KTS EARLY THIS MORNING WILL
INCREASE INTO THE 10-15KT RANGE BY MID MORNING WITH GUSTS INTO THE
UPPER TEEN RANGE DEVELOPING BY MID/LATE MORNING. POTENTIAL FOR
STRONGER GUSTS...ESPECIALLY ACROSS NORTHWEST IL AND RFD...BUT WILL
BE DEPENDENT ON CLOUD COVER/PRECIP COVERAGE. CMS
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM FOR ISOLATED SHRA/TSRA FROM MID MORNING THRU EARLY
EVENING...LOW FOR COVERAGE AND TIMING.
* MEDIUM FOR WINDS THRU THE PERIOD. CMS
//OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z...
SUNDAY THROUGH TUESDAY...CHC OF TSRA AND MVFR CIGS.
WEDNESDAY THROUGH THURSDAY...MAINLY VFR AND DRY.
BEACHLER
&&
.MARINE...
240 AM...HIGH PRESSURE OVER NEW ENGLAND WILL SLOWLY DRIFT OFF THE
EAST COAST SUNDAY AND SUNDAY NIGHT. A LARGE TROUGH OF LOW PRESSURE
EXTENDING FROM MANITOBA TO KANSAS WILL SLOWLY DRIFT NORTH FORMING
A DEEP AREA OF LOW PRESSURE OVER SOUTHERN MANITOBA ON SUNDAY. THE
GRADIENT WILL SLOWLY TIGHTEN AS THIS OCCURS WITH SOUTHERLY WINDS
INCREASING INTO THE 15-25KT RANGE OVER LAKE MICHIGAN. THE LOW WILL
SLOWLY MOVE NORTHEAST REACHING JAMES BAY TUESDAY WITH A TRAILING
COLD FRONT MOVING ACROSS THE LAKE MONDAY NIGHT OR TUESDAY MORNING.
THE STRONGEST WINDS WILL LIKELY BE AHEAD OF THIS COLD FRONT...ON
MONDAY. WINDS THEN SHIFT WESTERLY BEHIND THE FRONT. THE STRONGER
WINDS ARE EXPECTED TO PREVENT ANY WIDESPREAD DENSE FOG OVER THE
LAKE BUT WILL MAINTAIN CURRENT HAZE/PATCHY DENSE FOG WORDING. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
240 AM CDT SAT JUN 28 2014
.DISCUSSION...
325 PM CDT
MAIN FORECAST CONCERNS/CHALLENGES ARE WITH THUNDERSTORM CHANCES
THROUGH THE PERIOD WITH AN INCREASING POSSIBILITY FOR STRONGER AND
MORE ORGANIZED THUNDERSTORMS LATE IN THE WEEKEND AND EARLY NEXT
WEEK.
LOW STRATUS AND FOG HAVE FINALLY EXITED TO THE NORTH OF THE
ILLINOIS/INDIANA LAKE MICHIGAN SHORE TODAY AS STRONGER SOUTHERLY
FLOW HAS ALLOWED FOR A PUSH OF WARMER AIR INTO THE REGION. THE
LAST OF THIS STRATUS SHIELD CAN BE NOTED PUSHING INTO THE
MILWAUKEE AREA...WITH ALL LOCAL WEBCAMS SHOWING VERY LITTLE NO LOW
CLOUDS OR FOG AT ALL AT THIS TIME. WHAT IS PRESENT THOUGH IS HAZE
AND IS MORE PREDOMINANT ONCE AGAIN NEAR THE SHORE. THIS WILL
LIKELY REMAIN A FEATURE THIS EVENING AND OVERNIGHT...WITH ANY
DENSE FOG THAT REDEVELOPS LATER THIS EVENING TO REMAIN OFFSHORE
AND TO THE NORTH OF THE AREA. ABOUT THE ONLY AREA WHICH COULD
OBSERVE THIS REDEVELOPING FOG IS FAR NORTHEAST LAKE COUNTY
ILLINOIS BUT WITH CONFIDENCE LOW...HAVE LEFT OUT ANY MENTION AT
THIS TIME BUT WILL MONITOR TRENDS THIS AFTERNOON.
WITH WARM FRONT LIFTING NORTH THROUGH NORTHERN ILLINOIS AND
NORTHWEST INDIANA TODAY...MUCH WARMER AND MORE MOIST CONDITIONS
HAVE PREVAILED SOUTH OF IT. TEMPERATURES TO THE SOUTH OF THIS
FRONT ARE IN THE MID UPPER 80S AND WITH TEMPS TO THE NORTH
REMAINING IN THE MID TO UPPER 70S. LATEST RADAR IMAGERY DEPICTING
THIS WARM FRONT SLOWLY TRYING TO PUSH NORTHWARD OVER FAR NORTHEAST
ILLINOIS...BUT IS OBSERVING SOME LAKE INFLUENCE RESISTANCE.
TEMPERATURE TRENDS FROM CHICAGO NORTHWARD MAY BE A LITTLE TRICKY
IN THE NEAR TERM WITH THE MOVEMENT OF THIS MEANDERING BOUNDARY
BEING KEY. WITH IT ALMOST ON THE DOORSTEPS OF DOWNTOWN
CHICAGO...ITS POSSIBLE FOR THE THE CURRENT 70 DEGREE TEMPS BEING
REPORTED TO RAPIDLY JUMP INTO THE 80S HERE OVER THE NEXT ONE TO
TWO HOURS WITH SIMILAR TRENDS POSSIBLE NORTHWARD. ALTHOUGH THE
LAKE INFLUENCE COULD EASILY DOMINATE THIS AFTERNOON INTO THE
EVENING ESPECIALLY AS SYNOPTIC SOUTHERLY WIND SPEEDS
SUBSIDE...WITH THE 70S MAINTAINING IN THESE AREAS. HAVE TRENDED
TOWARDS THIS COOLER SOLUTION THIS AFTERNOON AND EVENING...ONCE
AGAIN KEEPING THESE 70 DEGREE TEMPS IN PLACE.
ISOLATED SHOWER AND THUNDERSTORM DEVELOPMENT IS ONGOING ACROSS
EAST CENTRAL ILLINOIS THIS AFTERNOON...BUT IS REMAINING LIGHT AND
BRIEF AT THIS TIME. EXPECT THIS TREND TO CONTINUE THIS AFTERNOON
WITH NO REAL SURFACE FOCUS AND WITH WEAKLY FORCED UPPER LEVEL
SUPPORT OWING TO WEAK SHORT WAVE ENERGY APPROACHING FROM THE
SOUTH. ONLY EXPECT BRIEF HEAVY DOWNPOURS TO BE THE MAIN THREAT
THIS AFTERNOON...WITH WEAK FLOW/LOW BULK SHEAR VALUES IN PLACE.
EXPECT MOST AREAS ACROSS THE CWA HAVING SIMILAR LOW CHANCES FOR
THIS BRIEF DEVELOPMENT THIS AFTERNOON...BEFORE THIS CONVECTION
DIMINISHES IN THE EVENING. ANY BETTER DEVELOPMENT THIS
AFTERNOON/EARLY EVENING WELL WEST OF THE CWA SHOULD STAY TO THE
WEST/NORTHWEST AS IT DIMINISHES TONIGHT...BUT WITH SOME GUIDANCE
TRYING TO INDICATE FURTHER DEVELOPMENT ACROSS THE SOUTHEAST THIRD
OF THE CWA OVERNIGHT. THE APPROACHING WEAK WAVE WILL CONTINUE
EAST/NORTHEAST TONIGHT WITH SHOWER/THUNDERSTORM DEVELOPMENT TRYING
TO PERSIST. WITH THE ONGOING ISOLATED CONVECTION PARTIALLY
DIURNALLY DRIVEN...FEEL THAT THE MODELS ARE OVERDOING IT AND HAVE
THE ENTIRE CWA DRY LATE THIS EVENING THROUGH TONIGHT.
SIMILAR SITUATION TO UNFOLD ON SATURDAY WITH WEAK ENERGY TO MOVE
ACROSS WARM/MOIST AND UNSTABLE ENVIRONMENT. WILL LIKELY OBSERVE
QUICK CU DEVELOPMENT BY MID/LATE MORNING BEFORE ISOLATED TO
SCATTERED SHOWER/THUNDERSTORM DEVELOPMENT OCCURRING ONCE AGAIN
THROUGH THE AFTERNOON. BEST FLOW/SHORT WAVE ENERGY WILL ONCE AGAIN
REMAIN TO THE WEST/NORTHWEST AND WITH WEAK FLOW ALOFT...DONT
ANTICIPATE ANY STRONG/SEVERE STORMS BUT WITH HEAVY DOWNPOURS STILL
THE MAIN THREAT. SHORT WAVE TROUGH OVER IOWA WILL SWING
EAST/NORTHEAST ACROSS THE REGION SATURDAY NIGHT AND AS THIS
OCCURS...ASSOCIATED THUNDERSTORM DEVELOPMENT COULD RIDE VEERING
LLJ INTO NORTHERN ILLINOIS. DO INCREASE POPS INTO LATE SATURDAY
NIGHT TO HIGH CHANCE POPS ESPECIALLY FOR NORTHERN ILLINOIS...BUT
LIMITED POPS THERE WITH UNCERTAINTY TO A POSSIBLE DIMINISHING
TREND DURING THIS TIME. IF THIS DOES NOT DIMINISH...THERE COULD BE
THE POTENTIAL FOR SOME STRONGER STORM DEVELOPMENT...ESPECIALLY AS
THE LLJ BECOMES MORE ORIENTED TOWARD NORTHERN ILLINOIS.
CONFIDENCE IS LOWER WITH REGARDS TO THE END RESULT OF THE PRECIP
THAT COULD POSSIBLY MOVE INTO NORTHERN ILLINOIS SATURDAY NIGHT.
THAT BEING SAID...COULD SEE ANY STORMS THAT DO MOVE THROUGH THE
AREA SATURDAY NIGHT TO CONTINUE PUSHING THROUGH SUNDAY MORNING AS
THE MID LEVEL TROUGH CONTINUES EAST. SO MAINTAIN HIGH CHANCE POPS
SUNDAY MORNING BUT DO LOWER IN THE AFTERNOON...WITH THE DEPARTURE
THE BETTER DEVELOPMENT. DID LEAVE SOME MENTION OF CHANCE THUNDER
IN THE AFTERNOON...MAINLY ONLY OWING TO REDEVELOPING POP UP
CONVECTION IN THE AFTERNOON. THUNDERSTORM DEVELOPMENT WILL ONCE
AGAIN OCCUR SUNDAY NIGHT WEST OF THE CWA. ONCE AGAIN UNCERTAINTIES
OF EVOLUTION OF THUNDERSTORMS TO THE WEST REMAIN BUT WITH ANY
COMPLEX EITHER APPROACHING LATE SUNDAY NIGHT OR EARLY MONDAY
MORNING. ANY DIMINISHING TREND THAT OCCURS OUT AHEAD OF IT WILL
EITHER OCCUR TO THE NORTHWEST OF THE CWA OR ON TOP OF THE CWA.
EITHER WAY...CHANCES FOR STRONG TO SEVERE WEATHER INCREASE MONDAY
INTO MONDAY NIGHT AS MCS DEVELOPMENT WILL BE FAVORED AT SOME POINT
ESPECIALLY GOING INTO MONDAY NIGHT.
RODRIGUEZ
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* ISOLATED SHRA/TSRA MID MORNING THRU EARLY EVENING.
* GUSTY SOUTHERLY WINDS MID MORNING THRU SUNSET. CMS
//DISCUSSION...UPDATED 06Z...
MODELS SHOW A WEAK UPPER WAVE LIFTING NORTH ACROSS THE AREA LATER
THIS MORNING INTO THIS AFTERNOON WITH SOME DIFFERENCES REGARDING
TIMING AND LOCATION WITH SOME CONSENSUS FOR SHRA/TSRA ACTIVITY TO
DEVELOP SOUTH OF THE TERMINALS AND THEN LIFT NORTH ACROSS SOUTHERN
MI AND INDIANA. ITS POSSIBLE THAT ACTIVITY COULD BE DEVELOPING AS
EARLY AS 15Z-17Z BUT CONFIDENCE IS TOO LOW TO INCLUDE ANY
ADDITIONAL MENTION IN THIS FORECAST. A SLOWER MOVEMENT OF THIS
WAVE WOULD THEN ALLOW FOR LATER DEVELOPMENT...CLOSER TO THE TIMING
OF THE CURRENT PROB GROUP AND THEREFORE MADE NO CHANGES.
COMPLEX OF STORMS EXPECTED TO DEVELOP OVER THE PLAINS LATER TODAY
WILL CONTINUE EAST TONIGHT AND LIKELY BE DECAYING AS THEY MOVE
INTO NORTHWEST IL EARLY SUNDAY MORNING. CURRENT TIMING WOULD
SUGGEST ARRIVAL AFTER CURRENT END TIME OF THIS FORECAST...BUT
CONFIDENCE FOR ACTIVITY EARLY SUNDAY MORNING IS MEDIUM.
SOUTH/SOUTHEAST WINDS UNDER 10 KTS EARLY THIS MORNING WILL
INCREASE INTO THE 10-15KT RANGE BY MID MORNING WITH GUSTS INTO THE
UPPER TEEN RANGE DEVELOPING BY MID/LATE MORNING. POTENTIAL FOR
STRONGER GUSTS...ESPECIALLY ACROSS NORTHWEST IL AND RFD...BUT WILL
BE DEPENDENT ON CLOUD COVER/PRECIP COVERAGE. CMS
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM FOR ISOLATED SHRA/TSRA FROM MID MORNING THRU EARLY
EVENING...LOW FOR COVERAGE AND TIMING.
* MEDIUM FOR WINDS THRU THE PERIOD. CMS
//OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z...
SUNDAY THROUGH TUESDAY...CHC OF TSRA AND MVFR CIGS.
WEDNESDAY THROUGH THURSDAY...MAINLY VFR AND DRY.
BEACHLER
&&
.MARINE...
240 AM...HIGH PRESSURE OVER NEW ENGLAND WILL SLOWLY DRIFT OFF THE
EAST COAST SUNDAY AND SUNDAY NIGHT. A LARGE TROUGH OF LOW PRESSURE
EXTENDING FROM MANITOBA TO KANSAS WILL SLOWLY DRIFT NORTH FORMING
A DEEP AREA OF LOW PRESSURE OVER SOUTHERN MANITOBA ON SUNDAY. THE
GRADIENT WILL SLOWLY TIGHTEN AS THIS OCCURS WITH SOUTHERLY WINDS
INCREASING INTO THE 15-25KT RANGE OVER LAKE MICHIGAN. THE LOW WILL
SLOWLY MOVE NORTHEAST REACHING JAMES BAY TUESDAY WITH A TRAILING
COLD FRONT MOVING ACROSS THE LAKE MONDAY NIGHT OR TUESDAY MORNING.
THE STRONGEST WINDS WILL LIKELY BE AHEAD OF THIS COLD FRONT...ON
MONDAY. WINDS THEN SHIFT WESTERLY BEHIND THE FRONT. THE STRONGER
WINDS ARE EXPECTED TO PREVENT ANY WIDESPREAD DENSE FOG OVER THE
LAKE BUT WILL MAINTAIN CURRENT HAZE/PATCHY DENSE FOG WORDING. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
236 AM CDT Sat Jun 28 2014
.DISCUSSION...
ISSUED 235 AM CDT Sat Jun 28 2014
Fairly boring surface pattern continues across Illinois early
this morning, with maybe a hint of a boundary earlier near
Champaign having shifted a bit north toward Kankakee. 500 mb
analysis does show a weak trough/circulation over the area as
well, which has helped some showers linger in the eastern CWA.
Main activity was located out over the Plains, near a pair of
surface lows over South Dakota and the Oklahoma panhandle.
Main forecast challenge continues to be with rain chances over the
next few days, particularly on Monday and Monday night, which also
stands to be our best chance of severe weather.
SHORT TERM...Today through Monday night:
Elongated upper wave over the central and southern Plains will be
tracking toward the Mississippi Valley this weekend, but
flattening out a bit in the process as an upper low develops over
southern Manitoba. Ahead of this wave, shower and storm chances
will continue to be diurnally driven today, mainly late morning
through the afternoon. The air mass will remain juicy, and
precipitable waters of 1.8 inches and slow storm movement leading
to locally heavy rains again.
Mesoscale convective system (MCS) expected to form west of the
Mississippi River this evening, then track eastward overnight. The
evening models have a fairly sizable spread in how much of this
remains intact as it crosses into Illinois, with the Canadian
model the most robust, followed by the NAM. The ECMWF is weaker
but also slower, with the main thrust arriving Sunday morning.
Leaned a bit toward the NAM and brought in some likely PoP`s west
of I-55 late Saturday night and east of there Sunday morning. All
models are showing good agreement in a drying trend during the
afternoon from the west. Started the trend by dropping to slight
PoP`s west of I-55 during the afternoon, but this could likely be
dropped completely if subsequent model runs continue this trend.
Low pressure over Colorado/New Mexico expected to lift northeast
into the central Plains by early Monday, and will be drawn ahead
of the main wave moving into the upper Mississippi Valley. As
opposed to recent trends, there looks to be fairly decent shear
moving into the area on Monday, with 0-6km bulk shear around 40
knots across the northwest CWA and CAPE`s of 3000-4000 J/kg or
higher. Latest SPC Day3 convective outlook has most of the CWA in
a slight risk of severe weather. Line of convection with another
MCS expected to develop during the afternoon and move southeast.
Main question is whether this arrives soon enough to take
advantage of the afternoon heating. The NAM spreads some rain as
far east as I-55 during the afternoon, but the other models mostly
favor an evening arrival. As such, have limited likely PoP`s
during Monday afternoon to northwest of the Illinois River,
spreading it southeast toward the I-72 corridor during the
evening. Precipitable waters of 2-2.5" expected as this MCS
arrives, so will need to watch for flash flood potential by
evening across the northwest half of the forecast area.
LONG TERM...Tuesday through Friday:
Welcome pattern shift expected much of the period as a broad
trough passes through the Great Lakes and mid-Mississippi Valley.
850 mb temperatures dropping to around 9C by midday Wednesday
resulting in surface highs around 80 degrees Wednesday and
Thursday. Longer range models showing a heat dome building across
the Rockies with amplification of the surface ridge there. Some
gradual warming of the temperatures aloft will take place in our
area late in the week, but a surface high over the Great Lakes is
expected to keep conditions dry during most of this period.
Geelhart
&&
.AVIATION...
ISSUED 1150 PM CDT Fri Jun 27 2014
Broken mid level clouds 12-15k ft over central IL will continue
overnight but may break up later tonight from SW as weakening
short wave over west central IL pulls slowly NNE. GFS model shows
700-1500 foot broken to overcast ceilings late tonight until mid
morning Sat while NAM model keeps VFR ceilings. HRRR shows clouds
below 1K ft developing over eastern IL by CMI after 08Z tonight.
Will compromise and have scattered low clouds after 09Z and also
have light fog/haze with vsbys 4-6 miles til 14-15Z. Scattered to
broken cumulus clouds of 3-4k ft develop late by Sat morning with
weak short wave trof over central IL and continue into early Sat
evening along with isolated to scattered showers and
thunderstorms. Added VCSH during midday and early Sat afternoon
and also added prob30 group for thunderstorms with MVFR vsbys and
ceilings (possibly briefly lower in heavy rain cores) from 20Z-24Z.
SSE winds of 4-9 kts overnight to veer south and increase to 10-15
kts by 15Z/10 am Sat with few gusts of 15-20 kts late morning and
afternoon. South winds diminish to near 10 kts after sunset Sat
and convection and cumulus clouds also diminish around sunset.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1231 AM CDT SAT JUN 28 2014
.DISCUSSION...
325 PM CDT
MAIN FORECAST CONCERNS/CHALLENGES ARE WITH THUNDERSTORM CHANCES
THROUGH THE PERIOD WITH AN INCREASING POSSIBILITY FOR STRONGER AND
MORE ORGANIZED THUNDERSTORMS LATE IN THE WEEKEND AND EARLY NEXT
WEEK.
LOW STRATUS AND FOG HAVE FINALLY EXITED TO THE NORTH OF THE
ILLINOIS/INDIANA LAKE MICHIGAN SHORE TODAY AS STRONGER SOUTHERLY
FLOW HAS ALLOWED FOR A PUSH OF WARMER AIR INTO THE REGION. THE
LAST OF THIS STRATUS SHIELD CAN BE NOTED PUSHING INTO THE
MILWAUKEE AREA...WITH ALL LOCAL WEBCAMS SHOWING VERY LITTLE NO LOW
CLOUDS OR FOG AT ALL AT THIS TIME. WHAT IS PRESENT THOUGH IS HAZE
AND IS MORE PREDOMINANT ONCE AGAIN NEAR THE SHORE. THIS WILL
LIKELY REMAIN A FEATURE THIS EVENING AND OVERNIGHT...WITH ANY
DENSE FOG THAT REDEVELOPS LATER THIS EVENING TO REMAIN OFFSHORE
AND TO THE NORTH OF THE AREA. ABOUT THE ONLY AREA WHICH COULD
OBSERVE THIS REDEVELOPING FOG IS FAR NORTHEAST LAKE COUNTY
ILLINOIS BUT WITH CONFIDENCE LOW...HAVE LEFT OUT ANY MENTION AT
THIS TIME BUT WILL MONITOR TRENDS THIS AFTERNOON.
WITH WARM FRONT LIFTING NORTH THROUGH NORTHERN ILLINOIS AND
NORTHWEST INDIANA TODAY...MUCH WARMER AND MORE MOIST CONDITIONS
HAVE PREVAILED SOUTH OF IT. TEMPERATURES TO THE SOUTH OF THIS
FRONT ARE IN THE MID UPPER 80S AND WITH TEMPS TO THE NORTH
REMAINING IN THE MID TO UPPER 70S. LATEST RADAR IMAGERY DEPICTING
THIS WARM FRONT SLOWLY TRYING TO PUSH NORTHWARD OVER FAR NORTHEAST
ILLINOIS...BUT IS OBSERVING SOME LAKE INFLUENCE RESISTANCE.
TEMPERATURE TRENDS FROM CHICAGO NORTHWARD MAY BE A LITTLE TRICKY
IN THE NEAR TERM WITH THE MOVEMENT OF THIS MEANDERING BOUNDARY
BEING KEY. WITH IT ALMOST ON THE DOORSTEPS OF DOWNTOWN
CHICAGO...ITS POSSIBLE FOR THE THE CURRENT 70 DEGREE TEMPS BEING
REPORTED TO RAPIDLY JUMP INTO THE 80S HERE OVER THE NEXT ONE TO
TWO HOURS WITH SIMILAR TRENDS POSSIBLE NORTHWARD. ALTHOUGH THE
LAKE INFLUENCE COULD EASILY DOMINATE THIS AFTERNOON INTO THE
EVENING ESPECIALLY AS SYNOPTIC SOUTHERLY WIND SPEEDS
SUBSIDE...WITH THE 70S MAINTAINING IN THESE AREAS. HAVE TRENDED
TOWARDS THIS COOLER SOLUTION THIS AFTERNOON AND EVENING...ONCE
AGAIN KEEPING THESE 70 DEGREE TEMPS IN PLACE.
ISOLATED SHOWER AND THUNDERSTORM DEVELOPMENT IS ONGOING ACROSS
EAST CENTRAL ILLINOIS THIS AFTERNOON...BUT IS REMAINING LIGHT AND
BRIEF AT THIS TIME. EXPECT THIS TREND TO CONTINUE THIS AFTERNOON
WITH NO REAL SURFACE FOCUS AND WITH WEAKLY FORCED UPPER LEVEL
SUPPORT OWING TO WEAK SHORT WAVE ENERGY APPROACHING FROM THE
SOUTH. ONLY EXPECT BRIEF HEAVY DOWNPOURS TO BE THE MAIN THREAT
THIS AFTERNOON...WITH WEAK FLOW/LOW BULK SHEAR VALUES IN PLACE.
EXPECT MOST AREAS ACROSS THE CWA HAVING SIMILAR LOW CHANCES FOR
THIS BRIEF DEVELOPMENT THIS AFTERNOON...BEFORE THIS CONVECTION
DIMINISHES IN THE EVENING. ANY BETTER DEVELOPMENT THIS
AFTERNOON/EARLY EVENING WELL WEST OF THE CWA SHOULD STAY TO THE
WEST/NORTHWEST AS IT DIMINISHES TONIGHT...BUT WITH SOME GUIDANCE
TRYING TO INDICATE FURTHER DEVELOPMENT ACROSS THE SOUTHEAST THIRD
OF THE CWA OVERNIGHT. THE APPROACHING WEAK WAVE WILL CONTINUE
EAST/NORTHEAST TONIGHT WITH SHOWER/THUNDERSTORM DEVELOPMENT TRYING
TO PERSIST. WITH THE ONGOING ISOLATED CONVECTION PARTIALLY
DIURNALLY DRIVEN...FEEL THAT THE MODELS ARE OVERDOING IT AND HAVE
THE ENTIRE CWA DRY LATE THIS EVENING THROUGH TONIGHT.
SIMILAR SITUATION TO UNFOLD ON SATURDAY WITH WEAK ENERGY TO MOVE
ACROSS WARM/MOIST AND UNSTABLE ENVIRONMENT. WILL LIKELY OBSERVE
QUICK CU DEVELOPMENT BY MID/LATE MORNING BEFORE ISOLATED TO
SCATTERED SHOWER/THUNDERSTORM DEVELOPMENT OCCURRING ONCE AGAIN
THROUGH THE AFTERNOON. BEST FLOW/SHORT WAVE ENERGY WILL ONCE AGAIN
REMAIN TO THE WEST/NORTHWEST AND WITH WEAK FLOW ALOFT...DONT
ANTICIPATE ANY STRONG/SEVERE STORMS BUT WITH HEAVY DOWNPOURS STILL
THE MAIN THREAT. SHORT WAVE TROUGH OVER IOWA WILL SWING
EAST/NORTHEAST ACROSS THE REGION SATURDAY NIGHT AND AS THIS
OCCURS...ASSOCIATED THUNDERSTORM DEVELOPMENT COULD RIDE VEERING
LLJ INTO NORTHERN ILLINOIS. DO INCREASE POPS INTO LATE SATURDAY
NIGHT TO HIGH CHANCE POPS ESPECIALLY FOR NORTHERN ILLINOIS...BUT
LIMITED POPS THERE WITH UNCERTAINTY TO A POSSIBLE DIMINISHING
TREND DURING THIS TIME. IF THIS DOES NOT DIMINISH...THERE COULD BE
THE POTENTIAL FOR SOME STRONGER STORM DEVELOPMENT...ESPECIALLY AS
THE LLJ BECOMES MORE ORIENTED TOWARD NORTHERN ILLINOIS.
CONFIDENCE IS LOWER WITH REGARDS TO THE END RESULT OF THE PRECIP
THAT COULD POSSIBLY MOVE INTO NORTHERN ILLINOIS SATURDAY NIGHT.
THAT BEING SAID...COULD SEE ANY STORMS THAT DO MOVE THROUGH THE
AREA SATURDAY NIGHT TO CONTINUE PUSHING THROUGH SUNDAY MORNING AS
THE MID LEVEL TROUGH CONTINUES EAST. SO MAINTAIN HIGH CHANCE POPS
SUNDAY MORNING BUT DO LOWER IN THE AFTERNOON...WITH THE DEPARTURE
THE BETTER DEVELOPMENT. DID LEAVE SOME MENTION OF CHANCE THUNDER
IN THE AFTERNOON...MAINLY ONLY OWING TO REDEVELOPING POP UP
CONVECTION IN THE AFTERNOON. THUNDERSTORM DEVELOPMENT WILL ONCE
AGAIN OCCUR SUNDAY NIGHT WEST OF THE CWA. ONCE AGAIN UNCERTAINTIES
OF EVOLUTION OF THUNDERSTORMS TO THE WEST REMAIN BUT WITH ANY
COMPLEX EITHER APPROACHING LATE SUNDAY NIGHT OR EARLY MONDAY
MORNING. ANY DIMINISHING TREND THAT OCCURS OUT AHEAD OF IT WILL
EITHER OCCUR TO THE NORTHWEST OF THE CWA OR ON TOP OF THE CWA.
EITHER WAY...CHANCES FOR STRONG TO SEVERE WEATHER INCREASE MONDAY
INTO MONDAY NIGHT AS MCS DEVELOPMENT WILL BE FAVORED AT SOME POINT
ESPECIALLY GOING INTO MONDAY NIGHT.
RODRIGUEZ
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* ISOLATED SHRA/TSRA MID MORNING THRU EARLY EVENING.
* GUSTY SOUTHERLY WINDS MID MORNING THRU SUNSET. CMS
//DISCUSSION...UPDATED 06Z...
MODELS SHOW A WEAK UPPER WAVE LIFTING NORTH ACROSS THE AREA LATER
THIS MORNING INTO THIS AFTERNOON WITH SOME DIFFERENCES REGARDING
TIMING AND LOCATION WITH SOME CONSENSUS FOR SHRA/TSRA ACTIVITY TO
DEVELOP SOUTH OF THE TERMINALS AND THEN LIFT NORTH ACROSS SOUTHERN
MI AND INDIANA. ITS POSSIBLE THAT ACTIVITY COULD BE DEVELOPING AS
EARLY AS 15Z-17Z BUT CONFIDENCE IS TOO LOW TO INCLUDE ANY
ADDITIONAL MENTION IN THIS FORECAST. A SLOWER MOVEMENT OF THIS
WAVE WOULD THEN ALLOW FOR LATER DEVELOPMENT...CLOSER TO THE TIMING
OF THE CURRENT PROB GROUP AND THEREFORE MADE NO CHANGES.
COMPLEX OF STORMS EXPECTED TO DEVELOP OVER THE PLAINS LATER TODAY
WILL CONTINUE EAST TONIGHT AND LIKELY BE DECAYING AS THEY MOVE
INTO NORTHWEST IL EARLY SUNDAY MORNING. CURRENT TIMING WOULD
SUGGEST ARRIVAL AFTER CURRENT END TIME OF THIS FORECAST...BUT
CONFIDENCE FOR ACTIVITY EARLY SUNDAY MORNING IS MEDIUM.
SOUTH/SOUTHEAST WINDS UNDER 10 KTS EARLY THIS MORNING WILL
INCREASE INTO THE 10-15KT RANGE BY MID MORNING WITH GUSTS INTO THE
UPPER TEEN RANGE DEVELOPING BY MID/LATE MORNING. POTENTIAL FOR
STRONGER GUSTS...ESPECIALLY ACROSS NORTHWEST IL AND RFD...BUT WILL
BE DEPENDENT ON CLOUD COVER/PRECIP COVERAGE. CMS
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM FOR ISOLATED SHRA/TSRA FROM MID MORNING THRU EARLY
EVENING...LOW FOR COVERAGE AND TIMING.
* MEDIUM FOR WINDS THRU THE PERIOD. CMS
//OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z...
SUNDAY THROUGH TUESDAY...CHC OF TSRA AND MVFR CIGS.
WEDNESDAY THROUGH THURSDAY...MAINLY VFR AND DRY.
BEACHLER
&&
.MARINE...
211 PM CDT
PRIMARY FORECAST CONCERN INITIALLY IS WITH DENSE FOG POTENTIAL.
VISIBLE SATELLITE IMAGERY SHOWS FOG/LOW STRATUS RAPIDLY DISSIPATING
OVER THE LAKE THIS AFTERNOON WITH BETTER PUSH OF WARMER AIR MOVING.
WHILE HIGH DEWPOINTS WILL CONTINUE TO ADVECT IN THE AMBIENT AIR MASS
WILL ALSO BE CONSIDERABLY WARMER RAISING DOUBTS ABOUT HOW WIDESPREAD
DENSE FOG WILL BE COMPARED TO PREVIOUS DAYS. WILL BE ALLOWING DENSE
FOG ADVISORY TO EXPIRE AT 3 PM AS SCHEDULED WITH THE MAJORITY OF THE
LINGERING DENSE FOG NOW CONFINED TO WISCONSIN NEARSHORE WATERS.
WHILE HAZE AND POTENTIALLY SOME AREAS OF DENSE FOG (MAINLY NORTH)
WILL LINGER THROUGH THE WEEKEND...FIGURE THE STRENGTHENING SOUTHERLY
FLOW WILL PROBABLY KEEP COVERAGE OF DENSE FOG MORE LIMITED.
IZZI
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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Area Forecast Discussion
National Weather Service Lincoln IL
1152 PM CDT Fri Jun 27 2014
.DISCUSSION...
ISSUED 900 PM CDT Fri Jun 27 2014
Forecast again on track tonight and main update is to remove the
evening period as isolated showers and thunderstorms have
dissipated around sunset. Partly to mostly cloudy skies tonight
with muggy lows getting close to dewpoints in the upper 60s to
around 70F. South to southeast winds 5 to 10 mph over central IL
and light in southeast IL.
Weakening short wave over sw IL will lift slowly nne across IL
overnight, but mostly dry conditions expected with convection more
diurnally driven during the afternoon and early evening hours.
More cloud cover tonight especially at mid levels along with a
bit higher SSE winds over central IL should keep fog from
forming. If southeast IL can clear out later tonight some patchy
ground fog could form where winds are light.
07
&&
.AVIATION...
ISSUED 1150 PM CDT Fri Jun 27 2014
Broken mid level clouds 12-15k ft over central IL will continue
overnight but may break up later tonight from sw as weakening
short wave over west central IL pulls slowly nne. GFS model shows
700-1500 foot broken to overcast ceings late tonight until mid
morning Sat while NAM model keeps VFR ceilings. HRRR shows clouds
below 1K ft developing over eastern IL by CMI after 08Z tonight.
Will compromise and have scattered low clouds after 09Z and also
have light fog/haze with vsbys 4-6 miles til 14-15Z. Scattered to
broken cumulus clouds of 3-4k ft develop late by Sat morning with
weak short wave trof over central IL and continue into early Sat
evening along with isolated to scattered showers and
thunderstorms. Added VCSH during midday and early Sat afternoon
and also added prob30 group for thunderstorms with MVFR vsbys and
ceilings (possibly briefly lower in heavy rain cores) from 20Z-24Z.
SSE winds of 4-9 kts overnight to veer south and increase to 10-15
kts by 15Z/10 am Sat with few gusts of 15-20 kts late morning and
afternoon. South winds diminish to near 10 kts after sunset Sat
and convection and cumulus clouds also diminish around sunset.
07
&&
.PREV DISCUSSION...
ISSUED 236 PM CDT Fri Jun 27 2014
SHORT TERM...Tonight through Monday: Another day of scattered diurnal
convection continues to fire over and in the vicinity of central
and southeast Illinois. Two short waves are evident on water vapor
imagery, one centered over Arkansas and the other over Iowa, are
helping to focus the convection, but weak shear profiles over the
forecast area should keep coverage pretty minimal here. Expect any
showers/storms locally to rapidly die off toward sunset, a common
theme for us the last several days.
A weak short wave is progged to be in our vicinity for Saturday,
which may help to focus the daily convection a little more than
today. However, shear profiles are still expected to be rather
weak (bulk shear less than 20 kts). Instability will be a little
better than today, with CAPE values as high as 2000 j/kg forecast
during peak heating.
A stronger short wave is progged to come through late Saturday
night into early Sunday. This feature should be accompanied by a
MCS which appears most likely to appear here late night
Saturday/early morning Sunday. The balance of Sunday should end up
fairly quiet behind this system.
Finally, our strongest short wave of the next several days is
expected to push into the area late Monday into Monday night.
There is some model spread in the timing of this wave, with the
NAM currently coming in a few hours faster than the model
consensus. The timing of this wave/surface cold front will be
important to the severe storm risk. The faster NAM solution would
be most favorable for severe storms, with the system arriving
closer to peak heating. However, at this point, the NAM is an
outlier and tend not to trust it at the end of its forecast range.
Also, even within the model consensus, there are disagreements
with respect to where the best pre-frontal shear/instability areas
will lie. That being said, most model solutions forecast
instability during peak heating in excess of 3000 j/kg, and bulk
shear values along/ahead of the front in excess of 30 kts. So, it
would appear severe storms are certainly possible late Monday into
Monday night, but the exact timing and location are unclear.
LONG TERM...Tuesday through Friday: The cold front should clear
the forecast area by early Tuesday if it has not already done so.
In the wake of the front, and driving upper wave, at least weakly
cyclonic upper flow will be with us for the rest of the work week.
However, the position of the trof axis supports high pressure
being in place at the surface locally. This pattern appears to be
supportive of temperatures trending to the cool side of normal,
with some highs in the 70s possible, as well as mostly dry
weather. While things could certainly change, model/ensemble
agreement is unusually good, providing a higher confidence
forecast than we have had lately.
BAK
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1251 PM CDT Sat Jun 28 2014
...Updated aviation section...
.SYNOPSIS...
ISSUED AT 413 AM CDT SAT JUN 28 2014
The 00z upper air analysis showed a 90 knot 250 millibar jet
extending from Oregon into northeast New Mexico. Broad upper level
troughing was in place from the Pacific Northwest into the central
and southern High Plains. A shortwave trough was moving across
eastern Colorado and New Mexico. Widespread thunderstorm activity
was slowly propagating southeast over central and southwest Kansas
early this morning. This activity was pushing an outflow boundary
south across southwest Kansas. Moist southerly low level flow was
riding up over the boundary and helping sustain the thunderstorm
complex.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 413 AM CDT SAT JUN 28 2014
Latest radar trends show the thunderstorm complex starting to weaken
somewhat. RAP 850 wind analysis has indicated a low level jet from
the Texas panhandle extending up into far southwest Kansas which has
been helping sustain the overnight convection. Latest progs show the
low level jet veering through the remainder of the early morning
hours which should help usher the complex eastward into central
Kansas. Will keep some high chance pops going over central Kansas
through the morning hours but the precipitation should come to an
end as the mid level shortwave moves east of the region. The models
continue to keep the low level boundary lingering in south central
Kansas later this afternoon. There could be some additional
thunderstorm development later this afternoon/early evening along
the boundary if it does get hung up in that area but with the upper
level dynamics shifting off to the east, any thunderstorm activity
should diminish fairly early this evening with the remainder of the
night staying dry.
.LONG TERM...(Sunday through Friday)
ISSUED AT 413 AM CDT SAT JUN 28 2014
Upper level westerly flow lifts into the northern part of the
country on Sunday. The westerly flow will result in a surface low
pressure trough in the lee of the Rockies. A weak fast moving
shortwave trough will push east through the northern plains. This
could bring a few showers and thunderstorms to the area around I-70
during the afternoon and evening.
A cold front will push south across western Kansas Monday afternoon
and night as a strong shortwave moves through the northern Plains.
Low level moisture will continue to stream northward into the
central Plains and impinge on the front, bringing another round of
thunderstorms to much of southwest Kansas. With saturated soil
conditions from tonight`s and previous days rains, flood and/or
flash flood headlines may be necessary.
The models show the front moving far enough south to bring a break
in rainfall across Southwest Kansas by Tuesday night into Wednesday.
Later in the week, upper level ridging will build from the western
states into the central part of the country. We should see a trend
toward somewhat warmer temperatures along with continued small
chances for thunderstorms through Friday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
ISSUED AT 1248 PM CDT SAT JUN 28 2014
VFR conditions will prevail today with mostly clear skies. Winds
will be from the south southwest this afternoon shifting to the
southeast this evening into the overnight period.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 88 66 94 72 / 20 20 10 10
GCK 88 65 95 70 / 10 10 10 10
EHA 92 62 100 70 / 0 0 10 10
LBL 91 66 98 73 / 10 10 10 10
HYS 86 66 94 71 / 50 10 20 20
P28 87 69 93 75 / 100 30 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...Gerard
SHORT TERM...Gerard
LONG TERM...Gerard
AVIATION...Hovorka_42
AREA FORECAST DISCUSSION
NWS TOPEKA KS
622 AM CDT Sat Jun 28 2014
...AVIATION UPDATE...
.SHORT TERM...(Today and Tonight)
Issued at 312 AM CDT SAT JUN 28 2014
08Z water vapor imagery and profiler data shows a negatively tilted
mid level trough from southwest KS northwest through the NEB
panhandle and into northeastern WY. At the surface, obs show a
general trough of low pressure from the southern highs plains
through the Dakotas with a moist airmass over central and eastern
KS.
Moisture advection from the low level jet has helped keep the
broken line of showers and thunderstorms going as the whole line
slowly progresses east. The forecast anticipates this line of storms
to gradually weaken as the low level jet slowly veers to the
southwest and moisture convergence diminishes. However by the late
morning or early afternoon, models bring the trough axis across
northeast KS with good forcing for precip to redevelop. The strength
of the storms this afternoon will hinge on how much destabilization
is able to occur. This is most likely over far eastern KS where some
insolation may take place. However deep layer shear around 25 to 30
KTS is on the low end needed for good supercell structure. With this
in mind there remains some uncertainty in how convection will evolve
this afternoon and the extent for severe weather. Model progs of
modest instability around 2000 J/kg, mainly over east central KS,
suggests there is the potential for some hail and wind. Perhaps the
greater hazard will be locally heavy rainfall. Concerned that with
the remnant outflow boundary from this mornings convection nearly
parallel to the mid level flow and PWs progged to be between 1.5 and
2 inches, that storms capable of heavy rainfall may tend to train
north northeast along the boundary. Considered the need for a flash
flood watch but have opted to hold off for now. Think that the upper
trough and forcing for convection should remain progressive enough
that the overall storms system should continue to propagate east.
Additionally flash flood guidance for one hour is around 2 inches.
Nevertheless later shifts will want to watch out for the flash flood
potential. Cloud cover and occasional precip is expected to hold
afternoon highs to around 80 or the lower 80s.
Think precip should come to an end rather quickly this evening as
the forcing from the upper trough rotates north and the right exit
region of the upper jet and its associated subsidence overspreads
northeast KS. Southerly winds should persist through the night since
there is no strong front expected to move through the area due to
the main surface wave forming north over the Dakotas. Therefore
think temps will remain relatively mild with lows for Sunday morning
around 70.
.LONG TERM...(Sunday through Friday)
Issued at 312 AM CDT SAT JUN 28 2014
Overnight showers and thunderstorms is expected to be east of the
CWA Sunday morning with the focus shifting to hot and humid
conditions for the afternoon. A broad surface trough of the
central CONUS is expected to deepen and lift northward while a
closed mid level wave shifts east over southern Canada. This will
usher a cold front southeast across the high plains into central
Nebraska by late afternoon. The tightening pressure gradient and
associated gusty south winds will advect low to mid 70 dewpoint
temps into the area. Temperatures also rise into the lower and
middle 90s, boosting heat indices in the 100 to 103 degree range.
A weakening capping inversion at h85 may allow a few thunderstorms
firing ahead of the frontal boundary to impact areas near the
Nebraska border by late afternoon. If they do, effective shear
near 40 kts and ample instability support rotating updrafts
capable of large hail and strong winds. Better thunderstorm
chances exist as the cold front and precip shifts southeast
towards the CWA Sunday evening. A stout 40 kt low level jet with
elevated CAPE at or above 2000 J/KG would maintain a chance for
isolated severe storms capable of hail and gusty winds.
Current guidance trends are focusing on Monday afternoon for
possible severe convection impacting a decent area of the CWA. Any
existing showers will exit Monday morning with the atmosphere
quickly destabilizing under mostly sunny skies. The cold front will
continue to progress southeastward through the morning, reaching
near the Interstate 70 corridor by late afternoon. Atmosphere
profiles suggest dewpoints in the low 70s and some mid level cooling
as a shortwave trough crossing the central plains. Weakening
inhibition will give way to near 4000 J/KG of surface CAPE as 0-6 KM
shear values back and increase to 40 kts. Given this environment,
scattered severe convection may develop along and ahead of the
boundary through early evening. Very large hail and damaging winds
would be the primary hazards. Afternoon highs ahead of the boundary
peak in the low to perhaps middle 90s with Tuesday morning lows in
the upper 60s.
Latest GFS and ECMWF maintain slightly variability on where the
frontal boundary and embedded shortwave trough stalls Tuesday. GFS
is further north into the area while the ECMWF develops organized
convection over southern Kansas. Not highly confident on
precipitation chances and will leave slight mention south of the KS
turnpike through Tuesday evening.
It appears there may finally be a dry period Wednesday and Thursday
as upper ridging builds into the area and organized vertical lift
focuses southward. Within the northwest flow on the eastern edge of
the ridge, could see overnight storms Thursday evening into Friday.
Temperatures from Tuesday onward will cool below normal in the low
to middle 80s. Drier air in place will make the apparent temperature
feel a bit less humid.
&&
.AVIATION...(For the 12Z TAFs through 12Z Sunday Morning)
Issued at 622 AM CDT SAT JUN 28 2014
There is quite a bit of uncertainty in how TS will evolve today.
Water vapor shows the mid level trough axis is still to the
southwest and the RAP and NAM continue to develop new convection
by the early afternoon over TOP and FOE. However with the outflow
pushing south and east of the terminals, am wondering if
thunderstorms development later today will be shifted southeast.
Will stay the course since the NAM and RAP show development. Think
precip will be ending by 00Z.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...Wolters
LONG TERM...Bowen
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
603 AM CDT Sat Jun 28 2014
...Updated aviation discussion...
.SYNOPSIS...
ISSUED AT 413 AM CDT SAT JUN 28 2014
The 00z upper air analysis showed a 90 knot 250 millibar jet
extending from Oregon into northeast New Mexico. Broad upper level
troughing was in place from the Pacific Northwest into the central
and southern High Plains. A shortwave trough was moving across
eastern Colorado and New Mexico. Widespread thunderstorm activity
was slowly propagating southeast over central and southwest Kansas
early this morning. This activity was pushing an outflow boundary
south across southwest Kansas. Moist southerly low level flow was
riding up over the boundary and helping sustain the thunderstorm
complex.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 413 AM CDT SAT JUN 28 2014
Latest radar trends show the thunderstorm complex starting to weaken
somewhat. RAP 850 wind analysis has indicated a low level jet from
the Texas panhandle extending up into far southwest Kansas which has
been helping sustain the overnight convection. Latest progs show the
low level jet veering through the remainder of the early morning
hours which should help usher the complex eastward into central
Kansas. Will keep some high chance pops going over central Kansas
through the morning hours but the precipitation should come to an
end as the mid level shortwave moves east of the region. The models
continue to keep the low level boundary lingering in south central
Kansas later this afternoon. There could be some additional
thunderstorm development later this afternoon/early evening along
the boundary if it does get hung up in that area but with the upper
level dynamics shifting off to the east, any thunderstorm activity
should diminish fairly early this evening with the remainder of the
night staying dry.
.LONG TERM...(Sunday through Friday)
ISSUED AT 413 AM CDT SAT JUN 28 2014
Upper level westerly flow lifts into the northern part of the
country on Sunday. The westerly flow will result in a surface low
pressure trough in the lee of the Rockies. A weak fast moving
shortwave trough will push east through the northern plains. This
could bring a few showers and thunderstorms to the area around I-70
during the afternoon and evening.
A cold front will push south across western Kansas Monday afternoon
and night as a strong shortwave moves through the northern Plains.
Low level moisture will continue to stream northward into the
central Plains and impinge on the front, bringing another round of
thunderstorms to much of southwest Kansas. With saturated soil
conditions from tonight`s and previous days rains, flood and/or
flash flood headlines may be necessary.
The models show the front moving far enough south to bring a break
in rainfall across Southwest Kansas by Tuesday night into Wednesday.
Later in the week, upper level ridging will build from the western
states into the central part of the country. We should see a trend
toward somewhat warmer temperatures along with continued small
chances for thunderstorms through Friday.
&&
.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)
ISSUED AT 603 AM CDT SAT JUN 28 2014
Scattered thunderstorms around Hays and Dodge City will gradually
move off to the east and southeast of those TAF sites early this
morning. VFR conditions will prevail through much of the day.
Later this afternoon, widely scattered thunderstorms could
develop over parts of central and southwest Kansas. Will carry
VCTS at Hays for a few hours late this afternoon.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 88 66 94 72 / 20 20 10 10
GCK 88 65 95 70 / 10 10 10 10
EHA 92 62 100 70 / 10 0 10 10
LBL 91 66 98 73 / 10 10 10 10
HYS 86 66 94 71 / 50 10 20 20
P28 87 69 93 75 / 50 30 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...Gerard
SHORT TERM...Gerard
LONG TERM...Gerard
AVIATION...Gerard
AREA FORECAST DISCUSSION
NWS GOODLAND KS
430 AM MDT SAT JUN 28 2014
.UPDATE...
ISSUED AT 430 AM MDT SAT JUN 28 2014
UPDATE SENT TO ADJUST POPS THIS MORNING THROUGH EARLY AFTERNOON.
PRECIP TO THE EAST EXITING A BIT FASTER WHILE TO THE WEST A SMALL
AREA OF SHOWERS ABOUT TO ENTER THE FORECAST AREA. 09Z RUC BRINGS
THE MOISTURE ASSOCIATED WITH THE SHOWERS ACROSS THE AREA THIS
MORNING SO HAVE ATTEMPTED TO TIME ITS PASSAGE IN THE GRIDS. NO
OTHER CHANGES MADE.
&&
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 300 AM MDT SAT JUN 28 2014
TODAY-TONIGHT...UPPER TROUGH AXIS AND AREA OF LIGHT PRECIPITATION
CURRENTLY COVERING THE FAR EAST THROUGH SOUTHEAST PARTS OF THE
AREA EXPECTED TO MOVE OUT SHORTLY AFTER SUNRISE OR PERHAPS 15Z
THIS MORNING. AROUND 18Z OR SO DRYLINE/WIND SHIFT EXPECTED ACROSS
THE FAR EAST WHERE CIN IS WEAK THUS CANT RULE OUT A FEW
SHOWERS/THUNDERSTORMS. FOR THE REST OF THE DAY AM EXPECTING ANY
PRECIPITATION OUT THE WAY TO SLOWLY MOVE EAST AS DRYER AIR MOVES
IN. FOR TONIGHT 06Z NAM AND A LESSER EXTENT 00Z GFS SHOWING SOME
ELEVATED INSTABILITY WITH WEAKENING INHIBITION ON NOSE OF 850 JET
PRIMARILY ALONG AND NORTH OF THE INTERSTATE. WILL HOLD OFF ON
INTRODUCING SMALL CHANCES FOR THUNDERSTORMS AT PRESENT TIME AND
LET NEXT SHIFT TAKE ANOTHER LOOK. HIGHS THIS AFTERNOON IN THE 80S
WITH LOWS TONIGHT IN THE MID 50S TO LOW 60S IN EASTERN
COLORADO...LOW TO MID 60S EAST OF THE BORDER.
SUNDAY-SUNDAY NIGHT...A FEW WEATHER DISTURBANCES EXPECTED TO MOVE
THROUGH WESTERLY FLOW ALOFT. MAY SEE A FEW THUNDERSTORMS IN THE
NORTHEAST PORTION OF THE AREA BY 18Z (COULD BE EXTENSION FOR
POSSIBLE STORMS EARLIER IN THE DAY/MORNING) WHERE SOME WEAK LOW
LEVEL WIND CONVERGENCE WORKS WITH FAVORABLE MOISTURE AND WEAKENING
CONVECTIVE INHIBITION. FOR THE REST OF THE DAY AND AREA INHIBITION
IS FURTHER WEAKENED AND CANT COMPLETELY RULE OUT AN ISOLATED STORM
SO I HAVE EXPECTED THE COVERAGE FURTHER WEST. THESE MOSTLY
DIURNALLY DRIVEN AFTERNOON STORMS SHOULD WEAKEN OR AT LEAST MOVE
EAST OUT OF THE AREA EARLY SUNDAY NIGHT. AFTERNOON TEMPERATURES
WARM INTO THE 90S WITH LOWS GENERALLY IN THE 60S. A FEW LOW 70S
POSSIBLE IN THE NORTON TO HILL CITY TO GOVE AREAS AND POINTS EAST.
MONDAY-MONDAY NIGHT...UPPER FLOW SHIFTS TO THE NORTHWEST WITH A
WEATHER DISTURBANCE REACHING THE WESTERN 1/3-1/2 OF THE AREA BY
DAYS END...SLIDING SOUTHEAST DURING THE NIGHT. NOT A WHOLE LOT OF
CHANGE TO POP/WX FORECAST AT THIS TIME. AFTERNOON TEMPERATURES
WILL BE COOLER WITH 80S FOR MOST...MAYBE SOME 90S FROM HILL CITY
TO GOVE AND LEOTI. LOWS GENERALLY IN THE MID 50S TO LOW 60S. NORTH
WINDS 15-20 MPH AND GUSTY MONDAY MORNING SLOWLY VEERING TO THE
NORTHEAST WHILE ALSO SLOWLY DECREASING IN SPEED DURING THE
AFTERNOON.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 300 AM MDT SAT JUN 28 2014
MEDIUM RANGE DETERMINISTIC GUIDANCE IS IN REASONABLY GOOD AGREEMENT
ON PLACEMENT AND TIMING OF A SHORTWAVE QUICKLY MOVING EASTWARD
ACROSS THE CENTRAL PLAINS ON TUESDAY. A SYNOPTIC SCALE BOUNDARY
FORCED BY A PRECEDING SHORTWAVE WILL BE ORIENTED EAST TO WEST ACROSS
SOUTHWEST KANSAS. RELATIVELY DRY NORTHERLY LOW LEVEL FLOW WILL BE
PRESENT NORTH OF THIS BOUNDARY ACROSS THE ENTIRE FORECAST AREA.
OVERALL...GUIDANCE HAS TRENDED DEEPER AND MORE PRONOUNCED WITH THESE
SHORTWAVES AND CONSEQUENTLY FURTHER SOUTH WITH THE SURFACE BOUNDARY.
HAVE TRENDED POPS DOWNWARD SLIGHTLY FOR THE MIDDLE OF THE WEEK WITH
GREATEST COVERAGE EXPECTED SOUTH OF THE FORECAST AREA...CLOSER TO
THE BOUNDARY AND HIGHER LOW LEVEL MOISTURE.
A BUILDING UPPER RIDGE WILL BRING RISING HEIGHTS THURSDAY AND FRIDAY.
MEDIUM RANGE MODELS REMAIN IN AGREEMENT ON THE OVERALL PATTERN
DURING THIS PERIOD ALTHOUGH THE ECMWF IS LESS AMPLIFIED THAN GFS.
EITHER WAY A WARMING TREND WILL OCCUR THROUGHOUT THE WEEK. ALTHOUGH
SIGNIFICANT WARMING ALOFT OCCURS...MOIST LOW LEVEL SOUTHEASTERLY
FLOW AND SHARPENING LEE TROUGH MAY BE ENOUGH FOR AT LEAST ISOLATED
CONVECTION IN THE LATTER HALF OF THE EXTENDED PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 300 AM MDT SAT JUN 28 2014
KGLD...VFR EXPECTED THROUGH THE PERIOD. LIGHT NORTHWEST WINDS AT
TAF ISSUANCE FORECAST TO SLOWLY INCREASE THROUGH EARLY AFTERNOON
WITH SUSTAINED SPEEDS AROUND 15KTS WITH SOME HIGHER GUSTS. BY MID
TO LATE AFTERNOON SPEEDS FALL BELOW 12KTS. FOR TONIGHT
LIGHT/VARIABLE WINDS SLOWLY INCREASE FROM THE SOUTH TO SOUTHWEST
AT SPEEDS NEAR 10KTS. WILL HAVE TO WATCH FOR THUNDERSTORM CHANCES
IN THE 05Z-08Z TIMEFRAME SUNDAY MORNING.
KMCK...VFR EXPECTED THROUGH THE PERIOD. LIGHT WEST WINDS AT TAF
ISSUANCE EXPECTED TO REMAIN BELOW 10KTS THROUGH 18Z THEN INCREASE
INTO THE 10-13KT RANGE THIS AFTERNOON. LIGHT/VARIABLE WINDS
EXPECTED EARLY TONIGHT THEN SLOWLY BECOME SOUTH/SOUTHWESTERLY
AROUND 06KTS. WILL HAVE TO WATCH FOR THUNDERSTORM CHANCES IN THE
08Z-12Z TIMEFRAME SUNDAY MORNING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...99
SHORT TERM...99
LONG TERM...BRB
AVIATION...99
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
415 AM CDT Sat Jun 28 2014
...Updated synopsis, short and long term discussions...
.SYNOPSIS...
ISSUED AT 413 AM CDT SAT JUN 28 2014
The 00z upper air analysis showed a 90 knot 250 millibar jet
extending from Oregon into northeast New Mexico. Broad upper level
troughing was in place from the Pacific Northwest into the central
and southern High Plains. A shortwave trough was moving across
eastern Colorado and New Mexico. Widespread thunderstorm activity
was slowly propagating southeast over central and southwest Kansas
early this morning. This activity was pushing an outflow boundary
south across southwest Kansas. Moist southerly low level flow was
riding up over the boundary and helping sustain the thunderstorm
complex.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 413 AM CDT SAT JUN 28 2014
Latest radar trends show the thunderstorm complex starting to weaken
somewhat. RAP 850 wind analysis has indicated a low level jet from
the Texas panhandle extending up into far southwest Kansas which has
been helping sustain the overnight convection. Latest progs show the
low level jet veering through the remainder of the early morning
hours which should help usher the complex eastward into central
Kansas. Will keep some high chance pops going over central Kansas
through the morning hours but the precipitation should come to an
end as the mid level shortwave moves east of the region. The models
continue to keep the low level boundary lingering in south central
Kansas later this afternoon. There could be some additional
thunderstorm development later this afternoon/early evening along
the boundary if it does get hung up in that area but with the upper
level dynamics shifting off to the east, any thunderstorm activity
should diminish fairly early this evening with the remainder of the
night staying dry.
.LONG TERM...(Sunday through Friday)
ISSUED AT 413 AM CDT SAT JUN 28 2014
Upper level westerly flow lifts into the northern part of the
country on Sunday. The westerly flow will result in a surface low
pressure trough in the lee of the Rockies. A weak fast moving
shortwave trough will push east through the northern plains. This
could bring a few showers and thunderstorms to the area around I-70
during the afternoon and evening.
A cold front will push south across western Kansas Monday afternoon
and night as a strong shortwave moves through the northern Plains.
Low level moisture will continue to stream northward into the
central Plains and impinge on the front, bringing another round of
thunderstorms to much of southwest Kansas. With saturated soil
conditions from tonight`s and previous days rains, flood and/or
flash flood headlines may be necessary.
The models show the front moving far enough south to bring a break
in rainfall across Southwest Kansas by Tuesday night into Wednesday.
Later in the week, upper level ridging will build from the western
states into the central part of the country. We should see a trend
toward somewhat warmer temperatures along with continued small
chances for thunderstorms through Friday.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
ISSUED AT 102 AM CDT SAT JUN 28 2014
Clusters of thunderstorms will track east across central and
southwest Kansas through the early morning hours. Expect variable
and gusty winds along with MVFR visibilities in moderate to heavy
rain at the TAF sites as the storms move through. Conditions will
be improving across the area after 10z as the area of storms moves
east. There could be some MVFR visibility reductions in mist
around sunrise. While some uncertainty exists on areal coverage
and location, there could be additional thunderstorms developing
after 21z at Hays and Dodge City.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 88 66 94 72 / 20 20 10 10
GCK 88 65 95 70 / 10 10 10 10
EHA 92 62 100 70 / 10 0 10 10
LBL 91 66 98 73 / 10 10 10 10
HYS 86 66 94 71 / 50 10 20 20
P28 87 69 93 75 / 50 30 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...Gerard
SHORT TERM...Gerard
LONG TERM...Gerard
AVIATION...Gerard
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
102 AM CDT Sat Jun 28 2014
...Updated aviation discussion...
.SHORT TERM...(This afternoon through Saturday)
ISSUED AT 1128 AM CDT FRI JUN 27 2014
Later afternoon and evening thunderstorms are expected. The best
chance for storms will be near the I70 corridor where capping is
weaker and there is better moisture convergence.
Thermodynamically, the setup is impressive with 3500 J/kg of
SBCAPE, 8.5 C/KM lapse rates, and decent boundary layer dewpoints.
A few problems with today`s setup though. All the models show
backing upper level winds and only about 35 kt of 0-EL shear. This
suggests that storm mode tonight will likely be on the HP side.
PWATs are forecast to be in the 1.5" range, which is well above
normal. This also suggests storms with high precipitation
efficiency. Feel the most discrete storms will be up in GLD`s area,
where mean flow and boundary layer winds are more orthogonal.
There could be an isolated tornado up north, as the HRRR is
indicating some updraft helicity. In addition, low level
directional and speed shear is not that bad. Given the
aforementioned upper level shear, it won`t take long through before
you get cold pools and resultant upscale growth, so that should
cut down on the tornado chances. Precip will exit the area
late tonight. Additional MCS activity is possible tomorrow
afternoon, with better moisture convergence and lift along and
east of Highway 283.
.LONG TERM...(Saturday night through Friday)
ISSUED AT 1214 PM CDT FRI JUN 27 2014
The main upper jet and storm track shifts north on Sunday then a
northern branch upper trough swings across the Northern and Central
Plains late Monday and Monday night with a chance for thunderstorms.
Unsettled weather continues in back of the upper trough into
Thursday with northwest flow aloft and more chances for showers and
thunderstorms. By Friday and upper level ridge is forecast with dry
weather for a change.
At the surface, a deepening trough of low pressure in the Rockies
will give strong southerly winds of 25 to 35 mph on Sunday, with a
cold front moving across western Kansas late Monday and winds
shifting to the north and gusty. Cooler temps will follow the
front as high pressure builds into the Plains with weaker winds
into mid next week.
Lows will be mild in the 60s and 70s, with highs in the 90s Sunday
and Monday, cooling into the 80s Tuesday into Thursday behind the cold
front, then back into the 90s by Friday.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
ISSUED AT 102 AM CDT SAT JUN 28 2014
Clusters of thunderstorms will track east across central and
southwest Kansas through the early morning hours. Expect variable
and gusty winds along with MVFR visibilities in moderate to heavy
rain at the TAF sites as the storms move through. Conditions will
be improving across the area after 10z as the area of storms moves
east. There could be some MVFR visibility reductions in mist
around sunrise. While some uncertainty exists on areal coverage
and location, there could be additional thunderstorms developing
after 21z at Hays and Dodge City.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 67 95 74 91 / 10 10 10 20
GCK 66 97 72 91 / 10 10 10 10
EHA 63 101 70 95 / 0 0 10 20
LBL 67 99 74 95 / 10 0 10 20
HYS 67 95 72 89 / 10 10 10 10
P28 70 94 75 97 / 20 10 10 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Sugden
LONG TERM...Kruse
AVIATION...Gerard
AREA FORECAST DISCUSSION
NWS JACKSON KY
958 PM EDT SUN JUN 29 2014
.UPDATE...
ISSUED AT 958 PM EDT SUN JUN 29 2014
MCV CONTINUES TO SPAWN SCATTERED CONVECTION WEST OF I-75 SO WILL
KEEP WITH A MENTION OF SHOWERS AND ISOLATED STORMS THROUGH THE NIGHT
AS THIS SYSTEM PASSES THROUGH. ONLY SOME MINOR TWEAKS TO PRECIP
TIMING AND RAIN CHANCES WERE MADE...AND TEMPS WERE RAISED A DEGREE
OR TWO WITH AMPLE CLOUD COVER LIKELY KEEPING MOST LOCATIONS IN THE
UPPER 60S TO NEAR 70.
UPDATE ISSUED AT 746 PM EDT SUN JUN 29 2014
INITIAL CONVECTION ON OLD OUTFLOW HAS NOW EXITED THE AREA TO THE
NORTH AND EAST. MCV IS STILL EVIDENT OVER CENTRAL KENTUCKY AS IT
CHURNS TOWARD OUR AREA BUT STILL NOT EXACTLY SURE HOW THIS FEATURE
WILL BEHAVE AS IT CROSSES OUR AREA AFTER SUNSET. WILL STAY THE
COURSE WITH THE INHERITED IDEA OF AN INCREASE IN CONVECTION AGAIN
LATER THIS EVENING AND OVERNIGHT AND WATCH RADAR TRENDS OVER THE NEXT
COUPLE OF HOURS BEFORE ADJUSTING TONIGHT/S FORECAST ANY.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 306 PM EDT SUN JUN 29 2014
OUTFLOW FROM THE WESTERN TN MCS FROM EARLIER TODAY HAS IGNITED
NUMEROUS THUNDERSTORMS ACROSS THE SOUTHWEST PART OF THE FORECAST AREA
AND THESE CONTINUE TO ADVANCE NORTHEAST. STORMS HAVE BEEN MOVING NE
AT ABOUT 14 TO 18 KNOTS THUS LIMITING THE RESIDENCE TIME OF THE
EXTREMELY HEAVY RAIN. HOWEVER ADDITIONAL THUNDERSTORMS CONTINUE TO
DEVELOP UPSTREAM SO LOCALIZED FLASH FLOODING STILL REMAINS A THREAT
WITH PRECIPITABLE WATER IN EXCESS OF 1.6 INCHES. RADAR ESTIMATES OVER
1.5 INCHES IN WHITLEY COUNTY EARLIER THIS AFTERNOON.
WITH LOSS OF DAYTIME HEATING WE EXPECT A DECREASE IN THE SHOWERS AND
THUNDERSTORMS. HOWEVER THE REMNANT MESOSCALE CIRCULATION FROM THE TN
MCS SHOULD MOVE OVER OUR AREA TOWARDS MIDNIGHT. THERE IS SOME
INDICATION THAT THE LOW LEVEL JET WILL INCREASE AFTER 03Z AND THERE
WILL BE AN INCREASE IN 7H UVV. THE GFS IS MUCH MORE AGGRESSIVE WITH
THIS IDEA THAN THE NAM...BUT CONCEPTUALLY AN INCREASE IN CONVECTION
LATER TONIGHT MAKES SENSE. IN FACT THE LATEST HRRR IS ALSO SHOWING A
DECREASE IN CONVECTION EARLY TONIGHT AND THEN AN UPTICK LATER
TONIGHT. HAVE DECIDED TO FOLLOW THIS IDEA IN THE GRIDS...AND NOT
FOLLOW THE TYPICAL DIURNAL PROBABILITY OF PRECIPITATION CYCLE.
FOR MONDAY INTO MONDAY NIGHT WE EXPECT A MORE TYPICAL PATTERN OF
AFTERNOON AND EVENING CONVECTION WITH CONVECTION ENDING DURING THE
OVERNIGHT PERIOD OF MONDAY NIGHT INTO EARLY TUESDAY MORNING.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 306 PM EDT SUN JUN 29 2014
GIVEN THE TIME OF YEAR...MODELS ARE IN FAIRLY GOOD AGREEMENT INTO
NEXT WEEKEND. A RATHER SIGNIFICANT WEATHER CHANGE IS ON TAP FOR THE
END OF THE WEEK...JUST IN TIME FOR THE 4TH OF JULY WEEKEND.
TO START THE PERIOD...HEAT AND HUMIDITY WILL REMAIN IN PLACE ON
TUESDAY. A WEAKENING FRONTAL BOUNDARY WILL DROP IN FROM THE
NORTHWEST BY THE AFTERNOON HOURS. GIVEN THE INSTABILITY
EXPECTED...THIS SUBTLE FEATURE SHOULD BE ENOUGH TO WARRANT SCATTERED
SHOWERS AND STORMS AGAIN TUESDAY AFTERNOON AND EVENING. ISOLATED
SHOWERS MAY LINGER THROUGH THE NIGHT AS THE BOUNDARY STALLS OVERHEAD
AND CANNOT RULE OUT A SHOWER POPPING UP JUST ABOUT ANYWHERE.
BY WEDNESDAY...A SHARP TROUGH WILL BE DROPPING INTO THE CENTRAL
PLAINS AND GREAT LAKES REGION. HEAT AND HUMIDITY WILL AGAIN LEAD TO
ISOLATED TO SCATTERED SHOWERS AND STORMS DURING THE AFTERNOON.
HOWEVER...WE SEEM TO BE MISSING TRIGGERS...SO CONVECTION MAY NOT BE
ALL THAT WIDESPREAD. BY THURSDAY...A STRONG COLD FRONT FINALLY
PUSHES ITS WAY ACROSS EASTERN KENTUCKY WITH PROBABLY THE BEST
CHANCES FOR RAIN THIS WEEK. DRY...MUCH COOLER...AND LESS HUMID
CONDITIONS WILL THEN SURGE SOUTHWARD THURSDAY NIGHT INTO
INDEPENDENCE DAY SETTING UP A BEAUTIFUL HOLIDAY WEEKEND. THE COOLER
AND LESS HUMID CONDITIONS WILL PERSIST THROUGH SUNDAY WITH DEWPOINTS
DOWN INTO THE 50S AND POSSIBLY A FEW UPPER 40S. THIS WILL PROVIDE
COOL MORNINGS WITH LOWS WELL INTO THE 50S. HIGHS SHOULD REBOUND INTO
THE 80S EACH DAY...BUT THE LACK OF HUMIDITY WON`T MAKE IT FEEL QUITE
SO BAD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 746 PM EDT SUN JUN 29 2014
THUNDERSTORMS HAVE EXITED THE AREA FOR THE TIME BEING. HOWEVER AN
UPPER LEVEL DISTURBANCE WILL BRING AN INCREASED THREAT OF
THUNDERSTORMS AGAIN LATE THIS EVENING AND OVERNIGHT. FOG IS A BIG
WILD CARD. WE CURRENTLY EXPECT IT DEVELOP LATE IN THE NIGHT WITH IFR
OR WORSE CONDITIONS IMPACTING THE REGION INTO MONDAY MORNING. THIS
COULD SET IN MUCH QUICKER THAN CURRENTLY FORECAST IN THE TAFS SHOULD
THE INCOMING DISTURBANCE DIE OUT AND NOT PRODUCE ANY UPTICK IN
SHOWER/THUNDERSTORM ACTIVITY OVERNIGHT. WHATEVER HAPPENS...
CONDITIONS WILL GRADUALLY IMPROVE TO VFR AFTER 12Z MONDAY...BUT MORE
SCATTERED THUNDERSTORMS ARE EXPECTED MONDAY AFTERNOON.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ABE
SHORT TERM...SBH
LONG TERM...KAS
AVIATION...ABE
AREA FORECAST DISCUSSION
NWS JACKSON KY
746 PM EDT SUN JUN 29 2014
.UPDATE...
ISSUED AT 746 PM EDT SUN JUN 29 2014
INITIAL CONVECTION ON OLD OUTFLOW HAS NOW EXITED THE AREA TO THE
NORTH AND EAST. MCV IS STILL EVIDENT OVER CENTRAL KENTUCKY AS IT
CHURNS TOWARD OUR AREA BUT STILL NOT EXACTLY SURE HOW THIS FEATURE
WILL BEHAVE AS IT CROSSES OUR AREA AFTER SUNSET. WILL STAY THE
COURSE WITH THE INHERITED IDEA OF AN INCREASE IN CONVECTION AGAIN
LATER THIS EVENING AND OVERNIGHT AND WATCH RADAR TRENDS OVER THE NEXT
COUPLE OF HOURS BEFORE ADJUSTING TONIGHT/S FORECAST ANY.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 306 PM EDT SUN JUN 29 2014
OUTFLOW FROM THE WESTERN TN MCS FROM EARLIER TODAY HAS IGNITED
NUMEROUS THUNDERSTORMS ACROSS THE SOUTHWEST PART OF THE FORECAST AREA
AND THESE CONTINUE TO ADVANCE NORTHEAST. STORMS HAVE BEEN MOVING NE
AT ABOUT 14 TO 18 KNOTS THUS LIMITING THE RESIDENCE TIME OF THE
EXTREMELY HEAVY RAIN. HOWEVER ADDITIONAL THUNDERSTORMS CONTINUE TO
DEVELOP UPSTREAM SO LOCALIZED FLASH FLOODING STILL REMAINS A THREAT
WITH PRECIPITABLE WATER IN EXCESS OF 1.6 INCHES. RADAR ESTIMATES OVER
1.5 INCHES IN WHITLEY COUNTY EARLIER THIS AFTERNOON.
WITH LOSS OF DAYTIME HEATING WE EXPECT A DECREASE IN THE SHOWERS AND
THUNDERSTORMS. HOWEVER THE REMNANT MESOSCALE CIRCULATION FROM THE TN
MCS SHOULD MOVE OVER OUR AREA TOWARDS MIDNIGHT. THERE IS SOME
INDICATION THAT THE LOW LEVEL JET WILL INCREASE AFTER 03Z AND THERE
WILL BE AN INCREASE IN 7H UVV. THE GFS IS MUCH MORE AGGRESSIVE WITH
THIS IDEA THAN THE NAM...BUT CONCEPTUALLY AN INCREASE IN CONVECTION
LATER TONIGHT MAKES SENSE. IN FACT THE LATEST HRRR IS ALSO SHOWING A
DECREASE IN CONVECTION EARLY TONIGHT AND THEN AN UPTICK LATER
TONIGHT. HAVE DECIDED TO FOLLOW THIS IDEA IN THE GRIDS...AND NOT
FOLLOW THE TYPICAL DIURNAL PROBABILITY OF PRECIPITATION CYCLE.
FOR MONDAY INTO MONDAY NIGHT WE EXPECT A MORE TYPICAL PATTERN OF
AFTERNOON AND EVENING CONVECTION WITH CONVECTION ENDING DURING THE
OVERNIGHT PERIOD OF MONDAY NIGHT INTO EARLY TUESDAY MORNING.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 306 PM EDT SUN JUN 29 2014
GIVEN THE TIME OF YEAR...MODELS ARE IN FAIRLY GOOD AGREEMENT INTO
NEXT WEEKEND. A RATHER SIGNIFICANT WEATHER CHANGE IS ON TAP FOR THE
END OF THE WEEK...JUST IN TIME FOR THE 4TH OF JULY WEEKEND.
TO START THE PERIOD...HEAT AND HUMIDITY WILL REMAIN IN PLACE ON
TUESDAY. A WEAKENING FRONTAL BOUNDARY WILL DROP IN FROM THE
NORTHWEST BY THE AFTERNOON HOURS. GIVEN THE INSTABILITY
EXPECTED...THIS SUBTLE FEATURE SHOULD BE ENOUGH TO WARRANT SCATTERED
SHOWERS AND STORMS AGAIN TUESDAY AFTERNOON AND EVENING. ISOLATED
SHOWERS MAY LINGER THROUGH THE NIGHT AS THE BOUNDARY STALLS OVERHEAD
AND CANNOT RULE OUT A SHOWER POPPING UP JUST ABOUT ANYWHERE.
BY WEDNESDAY...A SHARP TROUGH WILL BE DROPPING INTO THE CENTRAL
PLAINS AND GREAT LAKES REGION. HEAT AND HUMIDITY WILL AGAIN LEAD TO
ISOLATED TO SCATTERED SHOWERS AND STORMS DURING THE AFTERNOON.
HOWEVER...WE SEEM TO BE MISSING TRIGGERS...SO CONVECTION MAY NOT BE
ALL THAT WIDESPREAD. BY THURSDAY...A STRONG COLD FRONT FINALLY
PUSHES ITS WAY ACROSS EASTERN KENTUCKY WITH PROBABLY THE BEST
CHANCES FOR RAIN THIS WEEK. DRY...MUCH COOLER...AND LESS HUMID
CONDITIONS WILL THEN SURGE SOUTHWARD THURSDAY NIGHT INTO
INDEPENDENCE DAY SETTING UP A BEAUTIFUL HOLIDAY WEEKEND. THE COOLER
AND LESS HUMID CONDITIONS WILL PERSIST THROUGH SUNDAY WITH DEWPOINTS
DOWN INTO THE 50S AND POSSIBLY A FEW UPPER 40S. THIS WILL PROVIDE
COOL MORNINGS WITH LOWS WELL INTO THE 50S. HIGHS SHOULD REBOUND INTO
THE 80S EACH DAY...BUT THE LACK OF HUMIDITY WON`T MAKE IT FEEL QUITE
SO BAD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 746 PM EDT SUN JUN 29 2014
THUNDERSTORMS HAVE EXITED THE AREA FOR THE TIME BEING. HOWEVER AN
UPPER LEVEL DISTURBANCE WILL BRING AN INCREASED THREAT OF
THUNDERSTORMS AGAIN LATE THIS EVENING AND OVERNIGHT. FOG IS A BIG
WILD CARD. WE CURRENTLY EXPECT IT DEVELOP LATE IN THE NIGHT WITH IFR
OR WORSE CONDITIONS IMPACTING THE REGION INTO MONDAY MORNING. THIS
COULD SET IN MUCH QUICKER THAN CURRENTLY FORECAST IN THE TAFS SHOULD
THE INCOMING DISTURBANCE DIE OUT AND NOT PRODUCE ANY UPTICK IN
SHOWER/THUNDERSTORM ACTIVITY OVERNIGHT. WHATEVER HAPPENS...
CONDITIONS WILL GRADUALLY IMPROVE TO VFR AFTER 12Z MONDAY...BUT MORE
SCATTERED THUNDERSTORMS ARE EXPECTED MONDAY AFTERNOON.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ABE
SHORT TERM...SBH
LONG TERM...KAS
AVIATION...ABE
AREA FORECAST DISCUSSION
NWS JACKSON KY
102 PM EDT SAT JUN 28 2014
.UPDATE...
ISSUED AT 102 PM EDT SAT JUN 28 2014
SHOWERS AND A FEW THUNDERSTORMS CONTINUE TO EXPAND NORTHEASTWARD
ACROSS EASTERN KENTUCKY. MOVEMENT HAS BEEN VERY SLOW AND SOME AREAS
IN THE NORTH OR NORTHEAST MAY NOT GET IN ON THE SHOWER/STORM ACTIVITY
UNTIL 21Z OR LATER. OF COURSE...GIVEN THE PEAK HEATING OF THE DAY
THIS AFTERNOON...A ROGUE SHOWER OR STORM CANNOT BE RULED OUT PRIOR TO
THE ARRIVAL OF THE MORE ORGANIZED ACTIVITY. OTHERWISE...ONLY MINOR
TWEAKS TO POPS AND WEATHER TO ACCOUNT FOR CURRENT TRENDS. DID ADJUST
TEMPERATURES DOWN A BIT GIVEN CLOUD COVER HAS SIGNIFICANTLY SLOWED
THE WARMING TREND THROUGH THE DAY.
UPDATE ISSUED AT 935 AM EDT SAT JUN 28 2014
UPDATED FORECAST TO REFINE POPS THROUGH THE MORNING HOURS AS SHOWERS
WILL LIKELY HOLD OFF IN THE EAST AND NORTHEAST UNTIL THE AFTERNOON
HOURS. OTHERWISE...FORECAST IS ON TRACK.
UPDATE ISSUED AT 740 AM EDT SAT JUN 28 2014
UPDATED THE GRIDS TO FINE TUNE POPS INTO THE FIRST PART OF THE
MORNING. ALSO BACKED OFF ON THE DENSE VALLEY FOG AS THE CLOUDS HAVE
BEEN ENOUGH TO KEEP THE LOWEST VISIBILITIES AT BAY. FINALLY...DID
TWEAK THE T/TD GRIDS TO REFLECT THE LATEST OBS AND TRENDS. UPDATES
HAVE BEEN SENT TO THE NDFD AND WEB SERVERS WITH A NEW ZFP TO FOLLOW
SHORTLY.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 355 AM EDT SAT JUN 28 2014
07Z SFC ANALYSIS SHOWS AN EXTENSIVE AREA OF LOW PRESSURE THROUGH THE
HIGH PLAINS AND A WASHED OUT STATIONARY BOUNDARY STREWN FROM NORTH
TO SOUTH ACROSS CENTRAL KENTUCKY. WHILE THE LATEST RADAR IMAGES SHOW
THE REMAINS OF EARLIER SHOWERS DYING OUT JUST SOUTH OF JKL...ON
SATELLITE...A MASS OF MID AND HIGH LEVEL CLOUDS ARE PUSHING NORTH
FROM THE GULF COAST...OVER THE TENNESSEE VALLEY...AND INTO KENTUCKY.
THESE CLOUDS ARE HELPING TO KEEP THE FOG TO A MINIMUM SO FAR THIS
NIGHT DESPITE THE POCKETS OF HEAVY RAIN THAT FELL DURING THE PAST
DAY. SIMILAR TO THE LAST SEVERAL NIGHTS...TEMPERATURES ARE RUNNING
IN THE UPPER 60S TO LOWER 70S WHILE DEWPOINTS REMAIN IN THE MID AND
UPPER 60S...MAKING FOR A WARM AND MUGGY NIGHT.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION
OF THE FORECAST. THEY ALL DEPICT RIDGING OVER THE SOUTHEAST PART OF
THE NATION AND DEEP TROUGHING OVER THE NORTHWEST THIRD OF THE
NATION. THE CORE OF THIS TROUGH SHIFTS EAST INTO SOUTH CENTRAL CANADA
TONIGHT BRUSHING PAST THE OHIO VALLEY AND LOWERING HEIGHTS A TAD INTO
SUNDAY. A FEW WAVES OF ENERGY WILL PASS OVER KENTUCKY THROUGH THE
WEEKEND ON THE NORTHERN FRINGE OF THE WEAK SOUTHEAST RIDGE. ONE OF
THESE IS PASSING THROUGH WESTERN KENTUCKY THIS MORNING...MOVING FROM
SOUTH TO NORTH. ANOTHER DECENT ONE WILL PUSH FROM WEST TO EAST OVER
KENTUCKY DURING THE LATTER PART OF THE DAY SUNDAY. WITH THE MODEL
AGREEMENT...FAVORED A GENERAL BLEND WITH A LEAN TOWARD THE HIGHER
RESOLUTION NAM12 AND HRRR FOR THE NEAR TERM.
SENSIBLE WEATHER WILL FEATURE A WARM...HUMID...AND STORMY COUPLE OF
DAYS AS THAT WEAK BOUNDARY REMAINS IN PLACE WITH AMPLE MOISTURE OVER
EAST KENTUCKY...PWS OVER 1.8 INCHES. THE CONVECTION WILL BE
AMPLIFIED BY THE DIURNAL CYCLE...PEAKING LATE EACH AFTERNOON AND
LINGERING WELL INTO THE EVENING. THE GRIDS WHERE CREATED WITH THIS
IN MIND...MAKING FOR SLIGHTLY LOWER HIGHS FOR MOST OF THE AREA TODAY
THAN WE SAW ON FRIDAY AND POPS TOPPING OUT IN THE 60 PERCENT RANGE.
GIVEN THE ENVIRONMENT...KEPT POPS IN THROUGH THE NIGHT WITH AT LEAST
A 20 PERCENT GOING AT ALL TIMES. PATCHY FOG WILL BE A POSSIBILITY...
BUT PROBABLY NOT TOO EXTENSIVE OR THICK GIVEN THE ANTICIPATED CLOUD
COVER. SIMILARLY...THE RIDGE TO VALLEY TEMPERATURE DIFFERENCES
TONIGHT WILL BE FAIRLY SMALL.
AGAIN USED THE BCCONSSHORT AS A STARTING POINT FOR THE T AND TD GRIDS
THROUGH THE FIRST 24 HOURS AND THEN THE BCCONSALL THEREAFTER. DID
MAKE SOME MINOR ADJUSTMENTS TO THE RIDGE AND VALLEY SPOTS TONIGHT. AS
FOR POPS...ENDED UP PRETTY CLOSE TO THE RATHER WET GFS MOS GUIDANCE
THROUGH THE SHORT TERM.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 335 AM EDT SAT JUN 28 2014
AN UPPER LEVEL SHORTWAVE PASSING OVER THE APPALACHIANS...ALONG WITH
A STREAM OF WARM MOIST AND UNSTABLE GULF AIR INTO THE OHIO RIVER
VALLEY REGION...WILL BE ENOUGH TO KEEP SHOWERS AND THUNDERSTORMS
GOING THROUGHOUT THE NIGHT SUNDAY NIGHT...AND CONTINUING INTO THE
DAY MONDAY. THE SHORTWAVE WILL BEGIN TO EXIT TO THE EAST BY LATE
MONDAY AFTERNOON...PULLING THE BEST PRECIP CHANCES WITH IT. BY
OVERNIGHT...LOSS OF DIURNAL HEATING...AND A BRIEF LULL IN THE
SYNOPTIC ACTIVITY...SHOULD BE ENOUGH TO REMOVE CONVECTIVE CHANCES
ALL TOGETHER ACROSS MUCH OF THE CWA.
THIS LULL IN THE ACTIVITY WILL BE SHORT-LIVED...AS A STRONG UPPER
LEVEL LOW MOVES JUST NORTH OF THE UPPER GREAT LAKES REGION BY
TUESDAY MORNING. AS IT MOVES EASTWARD...THIS WILL SERVE TO PUSH A
COLD FRONT TOWARDS AND EVENTUALLY ALONG THE OHIO RIVER VALLEY.
UNFORTUNATELY...RIDGING OVER THE SOUTHERN CONUS WILL PREVENT ANY
QUICK FORWARD PROGRESSION OF THIS BOUNDARY THROUGH KY. THIS WILL
LEAD TO CONVECTIVE CHANCES ONCE MORE FROM TUESDAY THROUGH WEDNESDAY
NIGHT. BY THIS POINT THE UPPER LEVEL TROUGH WILL HAVE EXTENDED DOWN
ACROSS MUCH OF THE EASTERN CONUS...EVENTUALLY PUSHING THE RIDGING
FURTHER TO THE SOUTH AND ALLOWING THE SURFACE FEATURES TO FINALLY
PROGRESS ALONG THE SAME PATTERN. AS THE SURFACE COLD FRONT PUSHES
THROUGH KY THURSDAY...WINDS WILL HAVE TURNED TO A NRLY DIRECTION.
THIS WILL PULL IN A MUCH ANTICIPATED DRIER AND COOLER AIR MASS INTO
THE OHIO VALLEY REGION. PRECIP CHANCES WILL SLOWLY TAPER OFF DURING
THE DAY THURSDAY AS THIS DRIER AIR WORKS IN FROM NORTH TO SOUTH.
DAYTIME HIGHS WILL BE SLIGHTLY COOLER WITH THE MORE NORTHERN
FLOW...REACHING THE LOW 80S FOR HIGHS.
SURFACE RIDGING WILL TAKE A STRONG HOLD FOR THE REMAINDER OF THE
FORECAST PERIOD. THIS SHOULD KEEP PRECIP CHANCES OUT OF THE FORECAST
FOR BOTH FRIDAY AND SATURDAY...AS WELL AS ALLOW FOR MOSTLY CLEAR
SKIES. AIRMASS MODIFICATION WILL TAKE PLACE HOWEVER...WITH GOOD
SOLAR RADIATION...SO EXPECT TEMPS TO BE ON THE RISE ONCE MORE. HIGHS
WILL REACH BACK UP INTO UPPER 80S BY SATURDAY. HOWEVER...ON THE SAME
NOTE...LOSS OF RADIATION OVERNIGHT WILL ALLOW TEMPS TO DROP BACK
DOWN INTO THE LOW 60S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 102 PM EDT SAT JUN 28 2014
SCATTERED TO NUMEROUS SHOWERS AND ISOLATED STORMS WILL CONTINUE TO
PUSH NORTHEAST ACROSS EASTERN KENTUCKY THROUGH THE AFTERNOON AND
EARLY EVENING HOURS. WHILE THE ORGANIZED SHOWERS AND STORMS HAVE
DEPARTED KSME AND KLOZ...ADDITIONAL ACITIVITY WILL REMAIN IN THE
VICINITY OF THESE AIRPORTS THROUGH THE REMAINDER OF THE DAY AND
CANNOT RULE OUT A SHOWER OR STORM DIRECTLY IMPACTING THESE AIRPORTS
LATER ON. HOWEVER...GIVEN THE SCATTERED NATURE OF THE
CONVECTION...OPTED TO GO WITH VCTS AND AMEND AS NECESSARY THIS
AFTERNOON. AS FOR KJKL AND KSJS...SHOWERS AND STORMS WILL BE PUSHING
INTO THESE AREAS AROUND 21Z OR A BIT FASTER. WE SHOULD SEE EVERYTHING
DIE OFF THIS EVENING AS INSTABILITY DECREASES AND CONDITIONS
STABILIZE ACROSS THE AREA. AN ISOLATED SHOWER COULD STILL IMPACT KSJS
INTO THE LATE EVENING HOURS...BUT NOT ENOUGH CONFIDENCE TO GO WITH IT
IN THE TAF. GIVEN THE HIGHER DEWPOINTS AND RAIN TODAY...FOG WILL BE A
CONCERN LATER TONIGHT AND WILL INCLUDE A MENTION OF FOG IN ALL OF THE
TAFS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KAS
SHORT TERM...GREIF
LONG TERM...JMW
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
935 AM EDT SAT JUN 28 2014
.UPDATE...
ISSUED AT 935 AM EDT SAT JUN 28 2014
UPDATED FORECAST TO REFINE POPS THROUGH THE MORNING HOURS AS SHOWERS
WILL LIKELY HOLD OFF IN THE EAST AND NORTHEAST UNTIL THE AFTERNOON
HOURS. OTHERWISE...FORECAST IS ON TRACK.
UPDATE ISSUED AT 740 AM EDT SAT JUN 28 2014
UPDATED THE GRIDS TO FINE TUNE POPS INTO THE FIRST PART OF THE
MORNING. ALSO BACKED OFF ON THE DENSE VALLEY FOG AS THE CLOUDS HAVE
BEEN ENOUGH TO KEEP THE LOWEST VISIBILITIES AT BAY. FINALLY...DID
TWEAK THE T/TD GRIDS TO REFLECT THE LATEST OBS AND TRENDS. UPDATES
HAVE BEEN SENT TO THE NDFD AND WEB SERVERS WITH A NEW ZFP TO FOLLOW
SHORTLY.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 355 AM EDT SAT JUN 28 2014
07Z SFC ANALYSIS SHOWS AN EXTENSIVE AREA OF LOW PRESSURE THROUGH THE
HIGH PLAINS AND A WASHED OUT STATIONARY BOUNDARY STREWN FROM NORTH
TO SOUTH ACROSS CENTRAL KENTUCKY. WHILE THE LATEST RADAR IMAGES SHOW
THE REMAINS OF EARLIER SHOWERS DYING OUT JUST SOUTH OF JKL...ON
SATELLITE...A MASS OF MID AND HIGH LEVEL CLOUDS ARE PUSHING NORTH
FROM THE GULF COAST...OVER THE TENNESSEE VALLEY...AND INTO KENTUCKY.
THESE CLOUDS ARE HELPING TO KEEP THE FOG TO A MINIMUM SO FAR THIS
NIGHT DESPITE THE POCKETS OF HEAVY RAIN THAT FELL DURING THE PAST
DAY. SIMILAR TO THE LAST SEVERAL NIGHTS...TEMPERATURES ARE RUNNING
IN THE UPPER 60S TO LOWER 70S WHILE DEWPOINTS REMAIN IN THE MID AND
UPPER 60S...MAKING FOR A WARM AND MUGGY NIGHT.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION
OF THE FORECAST. THEY ALL DEPICT RIDGING OVER THE SOUTHEAST PART OF
THE NATION AND DEEP TROUGHING OVER THE NORTHWEST THIRD OF THE
NATION. THE CORE OF THIS TROUGH SHIFTS EAST INTO SOUTH CENTRAL CANADA
TONIGHT BRUSHING PAST THE OHIO VALLEY AND LOWERING HEIGHTS A TAD INTO
SUNDAY. A FEW WAVES OF ENERGY WILL PASS OVER KENTUCKY THROUGH THE
WEEKEND ON THE NORTHERN FRINGE OF THE WEAK SOUTHEAST RIDGE. ONE OF
THESE IS PASSING THROUGH WESTERN KENTUCKY THIS MORNING...MOVING FROM
SOUTH TO NORTH. ANOTHER DECENT ONE WILL PUSH FROM WEST TO EAST OVER
KENTUCKY DURING THE LATTER PART OF THE DAY SUNDAY. WITH THE MODEL
AGREEMENT...FAVORED A GENERAL BLEND WITH A LEAN TOWARD THE HIGHER
RESOLUTION NAM12 AND HRRR FOR THE NEAR TERM.
SENSIBLE WEATHER WILL FEATURE A WARM...HUMID...AND STORMY COUPLE OF
DAYS AS THAT WEAK BOUNDARY REMAINS IN PLACE WITH AMPLE MOISTURE OVER
EAST KENTUCKY...PWS OVER 1.8 INCHES. THE CONVECTION WILL BE
AMPLIFIED BY THE DIURNAL CYCLE...PEAKING LATE EACH AFTERNOON AND
LINGERING WELL INTO THE EVENING. THE GRIDS WHERE CREATED WITH THIS
IN MIND...MAKING FOR SLIGHTLY LOWER HIGHS FOR MOST OF THE AREA TODAY
THAN WE SAW ON FRIDAY AND POPS TOPPING OUT IN THE 60 PERCENT RANGE.
GIVEN THE ENVIRONMENT...KEPT POPS IN THROUGH THE NIGHT WITH AT LEAST
A 20 PERCENT GOING AT ALL TIMES. PATCHY FOG WILL BE A POSSIBILITY...
BUT PROBABLY NOT TOO EXTENSIVE OR THICK GIVEN THE ANTICIPATED CLOUD
COVER. SIMILARLY...THE RIDGE TO VALLEY TEMPERATURE DIFFERENCES
TONIGHT WILL BE FAIRLY SMALL.
AGAIN USED THE BCCONSSHORT AS A STARTING POINT FOR THE T AND TD GRIDS
THROUGH THE FIRST 24 HOURS AND THEN THE BCCONSALL THEREAFTER. DID
MAKE SOME MINOR ADJUSTMENTS TO THE RIDGE AND VALLEY SPOTS TONIGHT. AS
FOR POPS...ENDED UP PRETTY CLOSE TO THE RATHER WET GFS MOS GUIDANCE
THROUGH THE SHORT TERM.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 335 AM EDT SAT JUN 28 2014
AN UPPER LEVEL SHORTWAVE PASSING OVER THE APPALACHIANS...ALONG WITH
A STREAM OF WARM MOIST AND UNSTABLE GULF AIR INTO THE OHIO RIVER
VALLEY REGION...WILL BE ENOUGH TO KEEP SHOWERS AND THUNDERSTORMS
GOING THROUGHOUT THE NIGHT SUNDAY NIGHT...AND CONTINUING INTO THE
DAY MONDAY. THE SHORTWAVE WILL BEGIN TO EXIT TO THE EAST BY LATE
MONDAY AFTERNOON...PULLING THE BEST PRECIP CHANCES WITH IT. BY
OVERNIGHT...LOSS OF DIURNAL HEATING...AND A BRIEF LULL IN THE
SYNOPTIC ACTIVITY...SHOULD BE ENOUGH TO REMOVE CONVECTIVE CHANCES
ALL TOGETHER ACROSS MUCH OF THE CWA.
THIS LULL IN THE ACTIVITY WILL BE SHORT-LIVED...AS A STRONG UPPER
LEVEL LOW MOVES JUST NORTH OF THE UPPER GREAT LAKES REGION BY
TUESDAY MORNING. AS IT MOVES EASTWARD...THIS WILL SERVE TO PUSH A
COLD FRONT TOWARDS AND EVENTUALLY ALONG THE OHIO RIVER VALLEY.
UNFORTUNATELY...RIDGING OVER THE SOUTHERN CONUS WILL PREVENT ANY
QUICK FORWARD PROGRESSION OF THIS BOUNDARY THROUGH KY. THIS WILL
LEAD TO CONVECTIVE CHANCES ONCE MORE FROM TUESDAY THROUGH WEDNESDAY
NIGHT. BY THIS POINT THE UPPER LEVEL TROUGH WILL HAVE EXTENDED DOWN
ACROSS MUCH OF THE EASTERN CONUS...EVENTUALLY PUSHING THE RIDGING
FURTHER TO THE SOUTH AND ALLOWING THE SURFACE FEATURES TO FINALLY
PROGRESS ALONG THE SAME PATTERN. AS THE SURFACE COLD FRONT PUSHES
THROUGH KY THURSDAY...WINDS WILL HAVE TURNED TO A NRLY DIRECTION.
THIS WILL PULL IN A MUCH ANTICIPATED DRIER AND COOLER AIR MASS INTO
THE OHIO VALLEY REGION. PRECIP CHANCES WILL SLOWLY TAPER OFF DURING
THE DAY THURSDAY AS THIS DRIER AIR WORKS IN FROM NORTH TO SOUTH.
DAYTIME HIGHS WILL BE SLIGHTLY COOLER WITH THE MORE NORTHERN
FLOW...REACHING THE LOW 80S FOR HIGHS.
SURFACE RIDGING WILL TAKE A STRONG HOLD FOR THE REMAINDER OF THE
FORECAST PERIOD. THIS SHOULD KEEP PRECIP CHANCES OUT OF THE FORECAST
FOR BOTH FRIDAY AND SATURDAY...AS WELL AS ALLOW FOR MOSTLY CLEAR
SKIES. AIRMASS MODIFICATION WILL TAKE PLACE HOWEVER...WITH GOOD
SOLAR RADIATION...SO EXPECT TEMPS TO BE ON THE RISE ONCE MORE. HIGHS
WILL REACH BACK UP INTO UPPER 80S BY SATURDAY. HOWEVER...ON THE SAME
NOTE...LOSS OF RADIATION OVERNIGHT WILL ALLOW TEMPS TO DROP BACK
DOWN INTO THE LOW 60S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 755 AM EDT SAT JUN 28 2014
JUST SOME MVFR FOG AROUND FOR THE NEXT HOUR OR TWO AT THE SME AND LOZ
SITES THEN ATTENTION WILL TURN TO THE POTENTIAL FOR CONVECTION
TODAY...WITH THE BIGGEST THREAT ANTICIPATED DURING THE 16 TO 22Z
TIME FRAME. HAVE INCLUDED A VCTS FOR THIS IN THE TAFS AND ALSO A
TEMPO TO MVFR VIS DURING THE FOUR HOUR BLOCK OF BEST CHANCES IN THE
MID TO LATE AFTERNOON. DID DROP THE VCTS BACK TO VCSH A COUPLE OF
HOURS AFTER SUNSET TONIGHT WITH JUST LOCAL POCKETS OF BR EXPECTED DUE
TO THE CLOUD COVER. WINDS WILL REMAIN LIGHT AND VARIABLE THROUGH THE
PERIOD...OUTSIDE OF ANY SLOW MOVING STORMS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KAS
SHORT TERM...GREIF
LONG TERM...JMW
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
755 AM EDT SAT JUN 28 2014
.UPDATE...
ISSUED AT 740 AM EDT SAT JUN 28 2014
UPDATED THE GRIDS TO FINE TUNE POPS INTO THE FIRST PART OF THE
MORNING. ALSO BACKED OFF ON THE DENSE VALLEY FOG AS THE CLOUDS HAVE
BEEN ENOUGH TO KEEP THE LOWEST VISIBILITIES AT BAY. FINALLY...DID
TWEAK THE T/TD GRIDS TO REFLECT THE LATEST OBS AND TRENDS. UPDATES
HAVE BEEN SENT TO THE NDFD AND WEB SERVERS WITH A NEW ZFP TO FOLLOW
SHORTLY.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 355 AM EDT SAT JUN 28 2014
07Z SFC ANALYSIS SHOWS AN EXTENSIVE AREA OF LOW PRESSURE THROUGH THE
HIGH PLAINS AND A WASHED OUT STATIONARY BOUNDARY STREWN FROM NORTH
TO SOUTH ACROSS CENTRAL KENTUCKY. WHILE THE LATEST RADAR IMAGES SHOW
THE REMAINS OF EARLIER SHOWERS DYING OUT JUST SOUTH OF JKL...ON
SATELLITE...A MASS OF MID AND HIGH LEVEL CLOUDS ARE PUSHING NORTH
FROM THE GULF COAST...OVER THE TENNESSEE VALLEY...AND INTO KENTUCKY.
THESE CLOUDS ARE HELPING TO KEEP THE FOG TO A MINIMUM SO FAR THIS
NIGHT DESPITE THE POCKETS OF HEAVY RAIN THAT FELL DURING THE PAST
DAY. SIMILAR TO THE LAST SEVERAL NIGHTS...TEMPERATURES ARE RUNNING
IN THE UPPER 60S TO LOWER 70S WHILE DEWPOINTS REMAIN IN THE MID AND
UPPER 60S...MAKING FOR A WARM AND MUGGY NIGHT.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION
OF THE FORECAST. THEY ALL DEPICT RIDGING OVER THE SOUTHEAST PART OF
THE NATION AND DEEP TROUGHING OVER THE NORTHWEST THIRD OF THE
NATION. THE CORE OF THIS TROUGH SHIFTS EAST INTO SOUTH CENTRAL CANADA
TONIGHT BRUSHING PAST THE OHIO VALLEY AND LOWERING HEIGHTS A TAD INTO
SUNDAY. A FEW WAVES OF ENERGY WILL PASS OVER KENTUCKY THROUGH THE
WEEKEND ON THE NORTHERN FRINGE OF THE WEAK SOUTHEAST RIDGE. ONE OF
THESE IS PASSING THROUGH WESTERN KENTUCKY THIS MORNING...MOVING FROM
SOUTH TO NORTH. ANOTHER DECENT ONE WILL PUSH FROM WEST TO EAST OVER
KENTUCKY DURING THE LATTER PART OF THE DAY SUNDAY. WITH THE MODEL
AGREEMENT...FAVORED A GENERAL BLEND WITH A LEAN TOWARD THE HIGHER
RESOLUTION NAM12 AND HRRR FOR THE NEAR TERM.
SENSIBLE WEATHER WILL FEATURE A WARM...HUMID...AND STORMY COUPLE OF
DAYS AS THAT WEAK BOUNDARY REMAINS IN PLACE WITH AMPLE MOISTURE OVER
EAST KENTUCKY...PWS OVER 1.8 INCHES. THE CONVECTION WILL BE
AMPLIFIED BY THE DIURNAL CYCLE...PEAKING LATE EACH AFTERNOON AND
LINGERING WELL INTO THE EVENING. THE GRIDS WHERE CREATED WITH THIS
IN MIND...MAKING FOR SLIGHTLY LOWER HIGHS FOR MOST OF THE AREA TODAY
THAN WE SAW ON FRIDAY AND POPS TOPPING OUT IN THE 60 PERCENT RANGE.
GIVEN THE ENVIRONMENT...KEPT POPS IN THROUGH THE NIGHT WITH AT LEAST
A 20 PERCENT GOING AT ALL TIMES. PATCHY FOG WILL BE A POSSIBILITY...
BUT PROBABLY NOT TOO EXTENSIVE OR THICK GIVEN THE ANTICIPATED CLOUD
COVER. SIMILARLY...THE RIDGE TO VALLEY TEMPERATURE DIFFERENCES
TONIGHT WILL BE FAIRLY SMALL.
AGAIN USED THE BCCONSSHORT AS A STARTING POINT FOR THE T AND TD GRIDS
THROUGH THE FIRST 24 HOURS AND THEN THE BCCONSALL THEREAFTER. DID
MAKE SOME MINOR ADJUSTMENTS TO THE RIDGE AND VALLEY SPOTS TONIGHT. AS
FOR POPS...ENDED UP PRETTY CLOSE TO THE RATHER WET GFS MOS GUIDANCE
THROUGH THE SHORT TERM.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 335 AM EDT SAT JUN 28 2014
AN UPPER LEVEL SHORTWAVE PASSING OVER THE APPALACHIANS...ALONG WITH
A STREAM OF WARM MOIST AND UNSTABLE GULF AIR INTO THE OHIO RIVER
VALLEY REGION...WILL BE ENOUGH TO KEEP SHOWERS AND THUNDERSTORMS
GOING THROUGHOUT THE NIGHT SUNDAY NIGHT...AND CONTINUING INTO THE
DAY MONDAY. THE SHORTWAVE WILL BEGIN TO EXIT TO THE EAST BY LATE
MONDAY AFTERNOON...PULLING THE BEST PRECIP CHANCES WITH IT. BY
OVERNIGHT...LOSS OF DIURNAL HEATING...AND A BRIEF LULL IN THE
SYNOPTIC ACTIVITY...SHOULD BE ENOUGH TO REMOVE CONVECTIVE CHANCES
ALL TOGETHER ACROSS MUCH OF THE CWA.
THIS LULL IN THE ACTIVITY WILL BE SHORT-LIVED...AS A STRONG UPPER
LEVEL LOW MOVES JUST NORTH OF THE UPPER GREAT LAKES REGION BY
TUESDAY MORNING. AS IT MOVES EASTWARD...THIS WILL SERVE TO PUSH A
COLD FRONT TOWARDS AND EVENTUALLY ALONG THE OHIO RIVER VALLEY.
UNFORTUNATELY...RIDGING OVER THE SOUTHERN CONUS WILL PREVENT ANY
QUICK FORWARD PROGRESSION OF THIS BOUNDARY THROUGH KY. THIS WILL
LEAD TO CONVECTIVE CHANCES ONCE MORE FROM TUESDAY THROUGH WEDNESDAY
NIGHT. BY THIS POINT THE UPPER LEVEL TROUGH WILL HAVE EXTENDED DOWN
ACROSS MUCH OF THE EASTERN CONUS...EVENTUALLY PUSHING THE RIDGING
FURTHER TO THE SOUTH AND ALLOWING THE SURFACE FEATURES TO FINALLY
PROGRESS ALONG THE SAME PATTERN. AS THE SURFACE COLD FRONT PUSHES
THROUGH KY THURSDAY...WINDS WILL HAVE TURNED TO A NRLY DIRECTION.
THIS WILL PULL IN A MUCH ANTICIPATED DRIER AND COOLER AIR MASS INTO
THE OHIO VALLEY REGION. PRECIP CHANCES WILL SLOWLY TAPER OFF DURING
THE DAY THURSDAY AS THIS DRIER AIR WORKS IN FROM NORTH TO SOUTH.
DAYTIME HIGHS WILL BE SLIGHTLY COOLER WITH THE MORE NORTHERN
FLOW...REACHING THE LOW 80S FOR HIGHS.
SURFACE RIDGING WILL TAKE A STRONG HOLD FOR THE REMAINDER OF THE
FORECAST PERIOD. THIS SHOULD KEEP PRECIP CHANCES OUT OF THE FORECAST
FOR BOTH FRIDAY AND SATURDAY...AS WELL AS ALLOW FOR MOSTLY CLEAR
SKIES. AIRMASS MODIFICATION WILL TAKE PLACE HOWEVER...WITH GOOD
SOLAR RADIATION...SO EXPECT TEMPS TO BE ON THE RISE ONCE MORE. HIGHS
WILL REACH BACK UP INTO UPPER 80S BY SATURDAY. HOWEVER...ON THE SAME
NOTE...LOSS OF RADIATION OVERNIGHT WILL ALLOW TEMPS TO DROP BACK
DOWN INTO THE LOW 60S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 755 AM EDT SAT JUN 28 2014
JUST SOME MVFR FOG AROUND FOR THE NEXT HOUR OR TWO AT THE SME AND LOZ
SITES THEN ATTENTION WILL TURN TO THE POTENTIAL FOR CONVECTION
TODAY...WITH THE BIGGEST THREAT ANTICIPATED DURING THE 16 TO 22Z
TIME FRAME. HAVE INCLUDED A VCTS FOR THIS IN THE TAFS AND ALSO A
TEMPO TO MVFR VIS DURING THE FOUR HOUR BLOCK OF BEST CHANCES IN THE
MID TO LATE AFTERNOON. DID DROP THE VCTS BACK TO VCSH A COUPLE OF
HOURS AFTER SUNSET TONIGHT WITH JUST LOCAL POCKETS OF BR EXPECTED DUE
TO THE CLOUD COVER. WINDS WILL REMAIN LIGHT AND VARIABLE THROUGH THE
PERIOD...OUTSIDE OF ANY SLOW MOVING STORMS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...GREIF
LONG TERM...JMW
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
355 AM EDT SAT JUN 28 2014
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 355 AM EDT SAT JUN 28 2014
07Z SFC ANALYSIS SHOWS AN EXTENSIVE AREA OF LOW PRESSURE THROUGH THE
HIGH PLAINS AND A WASHED OUT STATIONARY BOUNDARY STREWN FROM NORTH
TO SOUTH ACROSS CENTRAL KENTUCKY. WHILE THE LATEST RADAR IMAGES SHOW
THE REMAINS OF EARLIER SHOWERS DYING OUT JUST SOUTH OF JKL...ON
SATELLITE...A MASS OF MID AND HIGH LEVEL CLOUDS ARE PUSHING NORTH
FROM THE GULF COAST...OVER THE TENNESSEE VALLEY...AND INTO KENTUCKY.
THESE CLOUDS ARE HELPING TO KEEP THE FOG TO A MINIMUM SO FAR THIS
NIGHT DESPITE THE POCKETS OF HEAVY RAIN THAT FELL DURING THE PAST
DAY. SIMILAR TO THE LAST SEVERAL NIGHTS...TEMPERATURES ARE RUNNING
IN THE UPPER 60S TO LOWER 70S WHILE DEWPOINTS REMAIN IN THE MID AND
UPPER 60S...MAKING FOR A WARM AND MUGGY NIGHT.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION
OF THE FORECAST. THEY ALL DEPICT RIDGING OVER THE SOUTHEAST PART OF
THE NATION AND DEEP TROUGHING OVER THE NORTHWEST THIRD OF THE
NATION. THE CORE OF THIS TROUGH SHIFTS EAST INTO SOUTH CENTRAL CANADA
TONIGHT BRUSHING PAST THE OHIO VALLEY AND LOWERING HEIGHTS A TAD INTO
SUNDAY. A FEW WAVES OF ENERGY WILL PASS OVER KENTUCKY THROUGH THE
WEEKEND ON THE NORTHERN FRINGE OF THE WEAK SOUTHEAST RIDGE. ONE OF
THESE IS PASSING THROUGH WESTERN KENTUCKY THIS MORNING...MOVING FROM
SOUTH TO NORTH. ANOTHER DECENT ONE WILL PUSH FROM WEST TO EAST OVER
KENTUCKY DURING THE LATTER PART OF THE DAY SUNDAY. WITH THE MODEL
AGREEMENT...FAVORED A GENERAL BLEND WITH A LEAN TOWARD THE HIGHER
RESOLUTION NAM12 AND HRRR FOR THE NEAR TERM.
SENSIBLE WEATHER WILL FEATURE A WARM...HUMID...AND STORMY COUPLE OF
DAYS AS THAT WEAK BOUNDARY REMAINS IN PLACE WITH AMPLE MOISTURE OVER
EAST KENTUCKY...PWS OVER 1.8 INCHES. THE CONVECTION WILL BE
AMPLIFIED BY THE DIURNAL CYCLE...PEAKING LATE EACH AFTERNOON AND
LINGERING WELL INTO THE EVENING. THE GRIDS WHERE CREATED WITH THIS
IN MIND...MAKING FOR SLIGHTLY LOWER HIGHS FOR MOST OF THE AREA TODAY
THAN WE SAW ON FRIDAY AND POPS TOPPING OUT IN THE 60 PERCENT RANGE.
GIVEN THE ENVIRONMENT...KEPT POPS IN THROUGH THE NIGHT WITH AT LEAST
A 20 PERCENT GOING AT ALL TIMES. PATCHY FOG WILL BE A POSSIBILITY...
BUT PROBABLY NOT TOO EXTENSIVE OR THICK GIVEN THE ANTICIPATED CLOUD
COVER. SIMILARLY...THE RIDGE TO VALLEY TEMPERATURE DIFFERENCES
TONIGHT WILL BE FAIRLY SMALL.
AGAIN USED THE BCCONSSHORT AS A STARTING POINT FOR THE T AND TD GRIDS
THROUGH THE FIRST 24 HOURS AND THEN THE BCCONSALL THEREAFTER. DID
MAKE SOME MINOR ADJUSTMENTS TO THE RIDGE AND VALLEY SPOTS TONIGHT. AS
FOR POPS...ENDED UP PRETTY CLOSE TO THE RATHER WET GFS MOS GUIDANCE
THROUGH THE SHORT TERM.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 335 AM EDT SAT JUN 28 2014
AN UPPER LEVEL SHORTWAVE PASSING OVER THE APPALACHIANS...ALONG WITH
A STREAM OF WARM MOIST AND UNSTABLE GULF AIR INTO THE OHIO RIVER
VALLEY REGION...WILL BE ENOUGH TO KEEP SHOWERS AND THUNDERSTORMS
GOING THROUGHOUT THE NIGHT SUNDAY NIGHT...AND CONTINUING INTO THE
DAY MONDAY. THE SHORTWAVE WILL BEGIN TO EXIT TO THE EAST BY LATE
MONDAY AFTERNOON...PULLING THE BEST PRECIP CHANCES WITH IT. BY
OVERNIGHT...LOSS OF DIURNAL HEATING...AND A BRIEF LULL IN THE
SYNOPTIC ACTIVITY...SHOULD BE ENOUGH TO REMOVE CONVECTIVE CHANCES
ALL TOGETHER ACROSS MUCH OF THE CWA.
THIS LULL IN THE ACTIVITY WILL BE SHORT-LIVED...AS A STRONG UPPER
LEVEL LOW MOVES JUST NORTH OF THE UPPER GREAT LAKES REGION BY
TUESDAY MORNING. AS IT MOVES EASTWARD...THIS WILL SERVE TO PUSH A
COLD FRONT TOWARDS AND EVENTUALLY ALONG THE OHIO RIVER VALLEY.
UNFORTUNATELY...RIDGING OVER THE SOUTHERN CONUS WILL PREVENT ANY
QUICK FORWARD PROGRESSION OF THIS BOUNDARY THROUGH KY. THIS WILL
LEAD TO CONVECTIVE CHANCES ONCE MORE FROM TUESDAY THROUGH WEDNESDAY
NIGHT. BY THIS POINT THE UPPER LEVEL TROUGH WILL HAVE EXTENDED DOWN
ACROSS MUCH OF THE EASTERN CONUS...EVENTUALLY PUSHING THE RIDGING
FURTHER TO THE SOUTH AND ALLOWING THE SURFACE FEATURES TO FINALLY
PROGRESS ALONG THE SAME PATTERN. AS THE SURFACE COLD FRONT PUSHES
THROUGH KY THURSDAY...WINDS WILL HAVE TURNED TO A NRLY DIRECTION.
THIS WILL PULL IN A MUCH ANTICIPATED DRIER AND COOLER AIR MASS INTO
THE OHIO VALLEY REGION. PRECIP CHANCES WILL SLOWLY TAPER OFF DURING
THE DAY THURSDAY AS THIS DRIER AIR WORKS IN FROM NORTH TO SOUTH.
DAYTIME HIGHS WILL BE SLIGHTLY COOLER WITH THE MORE NORTHERN
FLOW...REACHING THE LOW 80S FOR HIGHS.
SURFACE RIDGING WILL TAKE A STRONG HOLD FOR THE REMAINDER OF THE
FORECAST PERIOD. THIS SHOULD KEEP PRECIP CHANCES OUT OF THE FORECAST
FOR BOTH FRIDAY AND SATURDAY...AS WELL AS ALLOW FOR MOSTLY CLEAR
SKIES. AIRMASS MODIFICATION WILL TAKE PLACE HOWEVER...WITH GOOD
SOLAR RADIATION...SO EXPECT TEMPS TO BE ON THE RISE ONCE MORE. HIGHS
WILL REACH BACK UP INTO UPPER 80S BY SATURDAY. HOWEVER...ON THE SAME
NOTE...LOSS OF RADIATION OVERNIGHT WILL ALLOW TEMPS TO DROP BACK
DOWN INTO THE LOW 60S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 200 AM EDT SAT JUN 28 2014
DUE TO THE EARLIER SHOWERS AND STORMS...FOG WILL BE A CONCERN AT SME
THROUGH THE NIGHT...ALTHOUGH ADDITIONAL CLOUD COVER AND SLIGHT
SOUTHERLY WINDS DEVELOPING OVERNIGHT MAY KEEP IFR OR WORSE
CONDITIONS FROM BECOMING PREDOMINANT FOR THE BULK OF THE TIME INTO
DAWN. ALSO EXPECT SOME IFR OR WORSE FOG WITHIN THE DEEPER VALLEYS
ONCE AGAIN...BUT THAT SOUTHERLY WINDS AND CLOUD COVER SHOULD KEEP THE
FOG AT BAY AT SJS AND JKL COMPARED TO LAST NIGHT. CONVECTION WILL BE
POSSIBLE AT ALL SITES THROUGH THE DAY SATURDAY...WITH THE BIGGEST
THREAT BETWEEN THE 16 AND 22Z TIME FRAME. HAVE INCLUDED A VCTS FOR
THIS IN THE TAFS AND ALSO A TEMPO TO MVFR VIS DURING THE FOUR HOUR
BLOCK OF BEST CHANCES IN THE MID TO LATE AFTERNOON. WINDS WILL REMAIN
LIGHT AND VARIABLE THROUGH THE PERIOD...OUTSIDE OF ANY SLOW MOVING
STORMS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...JMW
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1227 AM EDT SAT JUN 28 2014
.SYNOPSIS...
HIGH PRESSURE CENTERED OVER NEW ENGLAND WILL MOVE OFFSHORE THIS
WEEKEND. A COLD FRONT IS EXPECTED TO APPROACH THE AREA FROM THE
NORTHWEST DURING MIDWEEK. HIGH PRESSURE IS EXPECTED TO BUILD OVER
THE AREA FOR THE 4TH OF JULY.
&&
.NEAR TERM /OVERNIGHT/...
OUR EYES ARE FIXED ON THE HVY RAFL OCCURRING ACROSS WRN MADISON TO
NWRN NELSON. RNK VWP IS MORE REPRESENTATIVE THAN LWX. THIS SHOWS
ERLY WINDS TO 10K FT. WHEN I SEE THIS SITUATION I THINK OF THE
MAJOR FLDG OF JUN `95. BUT THE LO LVL WINDS ARE MUCH WEAKER TNGT
AND NOT XPCTD TO LAST FOR MULTIPLE DAYS LK IN THAT CASE. HRRR SHOWS
THIS CONTINUING THRU ARND 10Z AND THEN DIMINISH. THE PROBLEM IS
THE RAIN IS FALLING IN A RLTVLY UNINHABITED AREA SO WE ARE NOT
RCVG ANY FLD REPORTS. FLSH FLD WRNGS IS IN EFFECT TIL 115 AM...BUT
UNLESS THE CELLS SHOW A RAPID WEAKENING WE`LL PRBLY BE XTND THE WRNG.
&&
.SHORT TERM /TODAY THROUGH MONDAY/...
HIPRES RDG...SFC THRU H5...REMAINS IN PLACE THRU SUNDAY. GIVEN
THE STBL AMS...WK LAPSE RATES...AND SELY FLOW...THINK THAT THE
CSTL PLAIN /E OF THE THE BLURDG/ SHUD HV A NICE DAY. MDL GDNC IN
AGREEMENT WRT MAXT IN THE MID 80S. BIGGEST WRINKLE MAY BE IN TERMS
OF CLDCVR...AS THE MID LVLS APPEAR TO BE MOIST ENUF FOR WAA-
INDUCED ALTOCU DVLPMNT. IN THE MTNS...ON THE OTHER
HAND...OROGRAPHIC LIFT AND DIURNAL HEATING MAY BE ENUF TO YIELD
SCT TSRA WHEN COMBINED W/ HIER CAPE VALUES. POP FCST ACCTS FOR
THAT. OVERALL...POPS HV BEEN TRIMMED.
WAA...AND MID DECK CLDS...INCREASE THRU THE NGT. DEWPTS MAY RISE A
CPL DEGF AS WMFNT APPROACHES. DEWS SUPPORT MOS MIN-T...AND WENT ON
THE HIER SIDE. HV TSRA DSPTG W/ LOSS OF DAYTIME HTG...AND HV
ATTEMPTED TO SQUEAK IN A DRY OVNGT PD. THATS NOT ON THE FIRMEST OF
FOOTING...DEPENDING UPON HOW QUICKLY S/WV ENERGY EJECTS EWD. BASED
ON AMPLITUDE OF UPA RDG...AM SIDING SLOWER.
WITH THAT IN MIND...PVA SHUD CROSS CWFA DURING THE DAY ON MON.
THAT/LL REDUCE AMPLITUDE OF UPA RDG...WHICH WL FOSTER A BETTER
OPPORTUNITY FOR TSRA AS SLY FLOW WL PERMIT WARMER AND MORE UNSTBL
AIR TO ADVANCE TWD I-95. TOOK MAXT INTO THE UPR 80S IN SPITE OF
AMPLE INSOLATION.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
POSITIVELY UPPER RIDGE IN PLACE STARTING NEXT WEEK WITH WARMING AND
HUMID CONDITIONS EXPECTED THROUGH AT LEAST MID WEEK. MODELS STILL
KEYING IN ON VORT MAX TRAVERSING RIDGE TOP MONDAY INTO MONDAY NIGHT
WITH SURFACE TROUGH AND DAYTIME HEATING TRIGGERING AFTERNOON STORMS
WEST THAT PUSH EAST ACROSS THE REGION THROUGH MONDAY EVENING.
PREFRONTAL TROUGH TUESDAY FOLLOWED BY "COLD" FRONT TUESDAY NIGHT AS
UPPER SHORT WAVE TROUGH AROUND THE BASE CANADIAN CLOSED LOW
APPROACHES...WILL BRING ADDITIONAL LIFTING MECHANISMS FOR ISOLATED
TO SCATTERED STORMS IN AN ALREADY UNSTABLE ENVIRONMENT. THE BEST
CHANCE FOR MORE WIDESPREAD AND STRONGER STORMS WILL COME WEDNESDAY
HOWEVER AS BASE OF LONG WAVE UPPER TROUGH LIFTS TOWARD
NORTHEAST...RESULTING IN DECREASED STABILITY WITH COOLER AIR ALOFT.
GFS MODEL SHOWS AXIS OF 4000+ J/KG MUCAPE IN PLACE WEDNESDAY. DEEP
LAYER SHEAR ALSO BECOMING MORE FAVORABLE THROUGH THE EVENING AS
HEIGHT GRADIENT TIGHTENS ALOFT. HUMIDITY DROPS FOR THURSDAY POST
FROPA...AND 4TH OF JULY IS STILL LOOKING GREAT WITH HIGH PRESSURE IN
PLACE.
&&
.AVIATION /04Z SATURDAY THROUGH WEDNESDAY/...
EASTERLY FLOW MAY BRING SOME LOW CLOUDS LATE TONIGHT...LOOKING
MOST LIKELY AT CHO PER GUIDANCE BUT CAN/T RULE OUT MRB/IAD BEING
AFFECTED. CONVECTION IS EXPECTED TO REMAIN WEST OF THE HUBS
SATURDAY. LOW VSBYS WILL ALSO BE POSSIBLE AT MRB/IAD.
GNLY VFR SUN-MON OUTSIDE OF CNVCTN. ON SUNDAY...CHC TSRA MAY MAKE IT
TO CHO/MRB. ALL TERMINALS STAND A BETTER CHC MON. WUDNT COMPLETELY
RULE OUT PATCHY PREDAWN FOG /MVFR/ ELY MON MRNG EITHER.
ISOLATED TO SCATTERED THUNDERSTORMS WILL BE POSSIBLE
EARLY NEXT WEEK IN AN UNSETTLED PATTERN. MORE WIDESPREAD ACTIVITY IS
EXPECTED WED AFTERNOON/EVENING AS A FRONT PUSHES THROUGH THE REGION.
HIGH PRESSURE WILL BUILD IN FOR THE END OF THE WEEK.
&&
.MARINE...
EASTERLY FLOW INCREASED ACROSS THE LOWER TIDAL POTOMAC AND MD BAY
SOUTH OF DRUM PT AND TANGIER SOUND LATE THIS AFTERNOON ADN EARLY
THIS EVENING. A SCA IS IN EFFECT THIS EVENING. FLOW SHOULD RELAX
LATE TONIGHT AND VEER TO THE SE AS HIGH PRESSURE MOVES OFF THE NEW
ENGLAND COAST. THIS MAY ENHANCE SPEEDS SOME OVER THE LOWER MD
BAY/LOWER TIDAL POTOMAC RIVER BUT CURRENTLY ARE EXPECTED TO REMAIN
BELOW SCA CRITERIA.
RDG OVER THE WATERS SUN WL MV TO THE E MON. FLOW WL VEER SLY...BUT
SPDS SHUD REMAIN BLO SCA CRIT.
UNSETTLED WEATHER PATTERN WILL BRING CHANCES OF
THUNDERSTORMS EARLY/MID NEXT WEEK. THE BEST CHANCE WILL BE WEDNESDAY
AFTERNOON/EVENING WITH A COLD FRONT. HIGH PRESSURE WILL BUILD IN FOR
THE END OF THE WEEK.
&&
.TIDES/COASTAL FLOODING...
WATER LEVELS ARE RUNNING ABOUT 1/2 FT ABOVE NORMAL THIS
EVENING AND ARE EXPECTED TO INCREASE TONIGHT INTO SATURDAY GIVEN AN
EASTERLY FLOW. A NEW MOON IS PRESENT TODAY AS WELL. MINOR COASTAL
FLOODING IS EXPECTED AT ANNAPOLIS EARLY SATURDAY MORNING. WILL
NEED TO WATCH WATER LEVELS AT FORT MCHENRY SINCE PREDICTIONS ARE
CLOSE TO MINOR THRESHOLDS.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...COASTAL FLOOD ADVISORY FROM 4 AM TO 9 AM EDT THIS MORNING FOR
MDZ014.
VA...NONE.
WV...NONE.
MARINE...NONE.
&&
$$
UPDATE...WOODY!
PRVS...HAS/HTS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
411 AM EDT SAT JUN 28 2014
.UPDATE...
ISSUED AT 1042 PM EDT FRI JUN 27 2014
SHRA AND ISOLD TSRA AFFECTING WESTERN UPR MICHIGAN THIS EVENING.
AFTER PRODUCING SOME ISOLD WIND DAMAGE OVER PORTIONS OF NORTHERN
WI IN NWS LA CROSSE CWA...THESE STORMS LOST PUNCH WHILE MOVING NORTH
AWAY FM GREATER MLCAPES OVER 1000 J/KG TO THE SOUTH AND WEST CLOSER
TO MAIN SFC WARM FRONT. DECENT AREA OF LIGHT TO MODERATE RAIN STILL
OVER THE WEST AS THE SHRA/TSRA ARE BEING DRIVEN BY SHORTWAVE LIFTING
OVER WESTERN LK SUPERIOR AND ASSOCIATED H85-H7 MOISTURE TRANSPORT.
HAD REPORT VIA SOCIAL MEDIA OF NEAR A THIRD OF AN INCH IN THE
IRONWOOD AREA THIS EVENING. FOLLOWING POCKET OF HIGHER H7-H5 RH OFF
RUC/NAM INDICATES SHORTWAVE AND LIFT WILL LIFT TOWARD SCNTRL LK
SUPERIOR OVERNIGHT TONIGHT. SINCE ISOLD SHRA/TSRA ARE OCCURRING OVR
CNTRL WI ON SOUTHERN EDGE OF BETTER FORCING AND THIS IS FORECAST TO
LIFT OVER CNTRL CWA...HAVE EXPANDED THE EASTERN EDGE OF SLIGHT CHANCE
POPS INTO DICKINSON AND MARQUETTE COUNTIES OVERNIGHT. 00Z HRRR COMPOSITIVE
REFLECTIVITY FORECAST ALSO SHOWING SIMILAR SCENARIO. CANNOT RULE OUT
ISOLD TSRA WITH BRIEF HEAVY DOWNPOUR AS 1-6KM MUCAPE IS STILL A FEW
HUNDRED J/KG AND PWATS REMAIN AROUND 175 PCT OF NORMAL.
STEADY SOUTH WIND AND INCREASING LOW-LEVEL MOISTURE WITH DWPNTS AOA
60 DEGREES HAS RESTRICTED TEMP FALL THUS FAR. NUDGED OVERNIGHT LOW
TEMPS UPWARD BY A FEW DEGREES...ESPECIALLY CLOSER TO LK SUPERIOR
WHERE THE SOUTH WINDS PROVIDE A BIT OF DOWNSLOPE WARMING.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 448 PM EDT FRI JUN 27 2014
THIS AFTERNOON INTO TONIGHT...THIS AFTERNOON A COUPLE SHORTWAVES TO
NOTE ARE SHOWING UP ON BOTH WV LOOP AND THE RUC ANALYSIS. THE FIRST
WAVE IS PUSHING SLOWLY THROUGH THE WESTERN HALF OF THE U.P. WHILE
THE NEXT ONE OVER SOUTHERN MN IS DIRECTLY BEHIND IT...BUT SLIGHTLY
WEST OF THE TRACK OF THE FIRST WAVE. THE FIRST WAVE HAS BEEN
TOUCHING OFF A FEW SHOWERS AND A COUPLE ISOLATED THUNDERSTORMS OVER
NORTHERN WI AND WESTERN UPPER MI...BUT THE OVERALL TREND FOR THE
PRECIP HAS BEEN TO VERY SLOWLY DIMINISHING. HI RES MODEL ANALYSIS
SHOWS THIS TREND IS EXPECTED TO CONTINUE INTO THE LATE AFTERNOON
HOURS. THIS MAKES SENSE AS MOST OF THE INSTABILITY AND BETTER
MOISTURE SOURCE IS MAINLY SOUTH AND WEST OF THE U.P. WITH ONLY MINOR
FORCING ASSOCIATED WITH THE WAVE AS IT PUSHES THROUGH THE WESTERN
U.P. ONCE THE FIRST WAVE PUSHES OUT OF THE U.P. LATE THIS AFTERNOON
THERE WILL BE A BIT OF A LULL IN THE PRECIP BEFORE THE SECOND WAVE
MOVES IN. THIS WAVE IS EXPECTED TO PUSH INTO THE WESTERN HALF OF THE
U.P. AROUND 00Z/28...THEREFORE...HAVE KEPT THE INCREASED CHANCE OF
SHOWERS AND THUNDERSTORMS IN THE FAR WEST AROUND THAT TIME AND
LINGERING THROUGH ABOUT 10Z. MUCH OF THE RAINFALL WILL OCCUR OVER
WESTERN LAKE SUPERIOR AND OVER THE ARROWHEAD OF MN...CLOSER TO THE
BETTER FORCING. HAVE ADDED PATCHY FOG IN THE FORECAST FOR MAINLY THE
SOUTH CENTRAL AND WEST HALF...MAINLY NEAR THE WI BORDER
OVERNIGHT...DUE LARGELY TO THE INCREASED SURFACE MOISTURE FROM RAIN
THIS AFTERNOON AND DUE TO THE OVERALL INCREASING DEWPOINTS OVER THE
AREA.
SATURDAY...AS THE AFOREMENTIONED SHORTWAVE CONTINUES TO LIFT TO THE
NORTH OVER WESTERN LAKE SUPERIOR...EXPECT LINGERING CHANCES OF
SHOWERS AND THUNDERSTORMS IN THE MORNING OVER THE WESTERN LAKE AND
OVER FAR WESTERN UPPER MI. THE MAIN TROUGH AND ASSOCIATED SURFACE
LOW OVER THE NORTHERN PLAINS ARE PROGGED TO INTENSIFY ALLOWING A
RIDGE OVER MUCH OF THE EASTERN U.S. TO STRENGTHEN AS WELL. THIS WILL
HELP THE WESTERN EDGE OF THE RIDGE TO REMAIN IN PLACE OVER THE
EASTERN HALF OF THE U.P. THROUGH MUCH OF THE DAY SATURDAY...KEEPING
MUCH OF THE PRECIPITATION CONFINED TO THE FAR WESTERN HALF OF THE
U.P. DRIER AIR WILL LIKELY LINGER OVER THE EAST HALF UNDER THE
INFLUENCE OF THE HIGH...WHICH WILL ALSO HELP REDUCE ANY CHANCE OF
SHOWERS AND THUNDERSTORMS. BY LATE SATURDAY AFTERNOON THE UPPER
LEVEL RIDGE AND UPPER LEVEL TROUGH WILL SHIFT SLOWLY EASTWARD. THIS
WILL ALLOW SHOWERS AND THUNDERSTORMS TO AGAIN INCREASE IN COVERAGE
OVER THE ARROWHEAD OF MN...WESTERN LAKE SUPERIOR AND OVER THE FAR
WESTERN U.P. AS MOISTURE/FORCING INCREASES OVER THOSE AREAS AS SHOWN
BY ANALYZING 1000-500RH ALONG WITH DEEP LAYER QCONV.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 409 AM EDT SAT JUN 28 2014
MAIN FCST CONCERNS DURING THE LONGER TERM PERIOD ARE FOCUSED ON THE
CHANCE FOR SHOWERS/TS ON SUN THRU MON AS A STRONG SW FLOW BTWN HI
PRES OFF THE E COAST AND DEEP LO PRES IN SCENTRAL CANADA ADVECTS
ABUNDANT MOISTURE INTO THE UPR LKS AND IS LIFTED AT TIMES BY
DISTURBANCES ROTATING ARND THE CNDN LO. THE TIMING AND TRACK OF
THESE DISTURBANCES ARE THE MOST CHALLENING ASPECTS OF THIS FCST.
TEMPS THRU MON WL BE RUNNING ABV NORMAL BEFORE COOLER AIR RETURNS ON
TUE FOLLOWING COLD FROPA ATTENDANT TO SFC/CLOSED LO SHIFTING E THRU
NW ONTARIO.
SUN...FAIRLY VIGOROUS SHRTWV AND ACCOMPANYING AXIS OF DEEP LYR
QVECTOR CNVGC AND HIER H85-5 RH ARE FCST TO SWING NEWD THRU THE UPR
LKS DURING THE MRNG TO THE SE OF DEEP UPR LO NEAR LK WINNIPEG AND
GIVE WAY TO A PERIOD OF DNVA/DEEP LYR QVECTOR DVGC AND DEEP DRYING.
THE MAJORITY OF THE NUMERICAL MODELS CONTINUE TO SHOW AN ILLOGICAL
NEGATIVE H85 THETA E ADVCTN UNDER THE AXIS OF THE DEEP LYR QVECTOR
CNVGC/HIER MID LVL RH. HOWEVER...WL MAINTAIN GOING FCST SHOWING
LIKELY POPS MARCHING SW TO NE ACRS THE CWA GIVEN THE RATHER
IMPRESSIVE SHRTWV AND OVERALL PWAT NEAR 1.50 INCHES /NEAR 170 PCT OF
NORMAL/. LIMITED DEEP LYR SHEAR GENERALLY AOB 30 KTS AND DISPARITY
BTWN DYNAMIC FORCING/ LLVL MSTR WL LIMIT THE SEVERITY OF ANY TS. IN
FACT...SPC HAS REMOVED THE SLGT RISK FOR SVR TS FOR THE CWA IN THEIR
LATEST OUTLOOK. SOME OF THE MODELS INDICATE ADDITIONAL SFC BASED
SHRA/TS WL DVLP IN THE AFTN WITH DAYTIME HEATING/DESTABILIZATION
FOLLOWING THE CLRG THAT WL LIFT HI TEMPS INTO THE 80S UNDER H85
TEMPS ARND 16C AND SBCAPES NEAR 1000 J/KG...BUT ADVERTISED
DRYING/NEGATIVE DYNAMICS THAT CONTRIBUTE TO CAP SHOWN BEST ON NAM
FCST SNDGS WARRANTS NO HIER THAN LO CHC POPS.
SUN NIGHT...ALTHOUGH THERE IS GENERAL AGREEMENT AMONG THE MODELS
ANOTHER WEAKER SHRTWV ROTATING ARND THE CLOSED LO TO THE NW WL MOVE
NEWD TOWARD THE UPR LKS...THERE IS DISAGREEMENT ON THE TIMING/TRACK
OF THIS DISTURBANCE. THE 00Z NAM IS QUITE A BIT FASTER AND FARTHER
TO THE NW...SHOWING THIS SHRTWV TRACKING RIGHT ACRS UPR MI DURING
THE EVNG. WL TEND TOWARD TOWARD THE OTHER GUIDANCE...WHICH SHOWS A
SLOWER SHRTWV FARTHER TO THE S...WHERE THE DYNAMIC SUPPORT WOULD
TRIGGER SCT SHRA/TS OVER THE SE CWA OVERNGT CLOSER TO AREA OF HIER
H85 THETA-E/MSTR GRADIENT LEFT IN THE WAKE OF SHRTWV THAT WL CROSS
THE FA ON SUN MRNG. THE BULK OF THESE MODELS HOWEVER SHOW THE NW
PART OF THE CWA REMAINING PCPN FREE WITH THE MID LVLS REMAINING TOO
DRY TO SUPPORT PCPN.
MON INTO MON NIGHT...CLOSED LO OVER SRN MANITOBA IS FCST TO DRIFT
INTO NW ONTARIO...AND MODELS INDICATE YET ANOTHER STRONGER SHRTWV/
AREA OF DEEP LYR QVECTOR CNVGC WL MOVE THRU THE UPR LKS ARND THAT
LARGER SCALE FEATURE. MODEL CONSENSUS IS ACTUALLY IN FAIR AGREEMENT
SHOWING ACCOMPANYING DEEP LYR QVECTOR CNVGC IMPACTING MAINLY THE SE
CWA IN THE 18Z MON-06Z TUE TIME ALONG LEFTOVER THERMAL/MSTR GRADIENT
AND AREA OF HIER H85 THETA E. LARGER SCALE DRYING IN THE WAKE OF
THIS PASSING DISTURBANCE DURING A PERIOD OF NOCTURNAL COOLING WL
RESULT IN DIMINISHING POPS ON MON NGT. BUT APRCHG UPR TROF AXIS/
PSBLY ANOTHER DISTURBANCE/BACKWASH MSTR FM THE W AND DEEP CYC FLOW
WARRANTS AT LEAST SOME LO CHC POPS OVER THE ENTIRE CWA THRU THE NGT.
TUE...A NUMBER OF THE MEDIUM RANGE MODELS HINT A SHRTWV ROTATING
ARND THE CLOSED LO DRIFTING E THRU ONTARIO AND WITHIN ARPCHG UPR
TROF AXIS EXTENDING S INTO THE WRN LKS WL IMPACT UPR MI. IN THE
PRESENCE OF DIURNAL HEATING AND GENERAL LLVL CYC FLOW...THERE WL BE
SOME SHOWERS/PSBLY A TS. TUE SHOULD BE QUITE A BIT COOLER AS H85
TEMPS FALL TOWARD 10C.
EXTENDED...AREA OF DEEPER MSTR UNDER THE UPR TROF AXIS EXTENDING S
INTO THE UPR LKS FM DEPARTING CLOSED LO SHIFTING INTO QUEBEC WL
BRING A GOOD DEAL OF CLD COVER AND PSBLY A LINGERING SHOWER TO THE
CWA ON WED...BUT RISING HGTS LATER IN THE DAY FOLLOWING THE PASSAGE
OF THE TROF AXIS SHOULD BRING MORE SUNSHINE. WITH TRAILING HI PRES
DOMINATING ON THU...EXPECT A MOSUNNY AND PLEASANT DAY. MODELS HAVE
TENDED TO SHIFT THIS HI MORE QUICKLY TO THE E BY FRI...WITH A RETURN
SW FLOW DVLPG OVER THE UPR LKS. THE EXTENDED MODELS ARE NOW HINTING
THERE COULD BE SOME SHOWERS/TS ON JULY 4TH AS A DISTURBANCE IN THE
MORE ZONAL FLOW ALOFT INTERACTS WITH THE RETURNING WARMER/MOISTER
AIR.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 110 AM EDT SAT JUN 28 2014
EXPECT SHRA AND PERHAPS AN ISOLD TSRA TO AFFECT KCMX EARLY THIS
MORNING...WITH JUST A SLIM CHANCE OF A SHRA/TSRA AT KIWD AND KSAW.
CONDITIONS SHOULD STAY VFR THOUGH. AFTER THE CHANCE OF RAIN ENDS
LATER THIS MORNING...EXPECT MAINLY QUIET WEATHER THROUGH MUCH OF
TODAY WITH SCT MID CLOUDS. NEXT CHANCE OF SHRA/TSRA WILL RETURN TO
KIWD LATER THIS EVENING. HAVE INCLUDED MENTION OF LOW-LEVEL WIND
SHEAR AS LOW-LEVEL JET IS OVERHEAD THIS MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 AM EDT SAT JUN 28 2014
ALTHOUGH THE PRES GRADIENT WILL BE TIGHTENING OVER THE UPPER LAKES
THRU EARLY NEXT WEEK ON THE SE FLANK OF AN UNSEASONABLY DEEP LO PRES
MOVING ENEWD THRU SCENTRAL CANADA...HI STABILITY OVER THE CHILLY
LAKE WATERS WL VERY LIKELY HOLD WINDS TO 25 KTS OR LESS THRU THIS
PERIOD. AS MORE HUMID AIR ARRIVES THRU THE WEEKEND OVER THE CHILLY
WATERS...EXPECT SOME FOG TO DEVELOP AND PERSIST UNTIL DRIER AIR
FOLLOWS A COLD FRONTAL PASSAGE AND WIND SHIFT TO THE W EARLY NEXT
WEEK.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...JLA
SHORT TERM...KEC
LONG TERM...KC
AVIATION...JLA
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
111 AM EDT SAT JUN 28 2014
.UPDATE...
ISSUED AT 1042 PM EDT FRI JUN 27 2014
SHRA AND ISOLD TSRA AFFECTING WESTERN UPR MICHIGAN THIS EVENING.
AFTER PRODUCING SOME ISOLD WIND DAMAGE OVER PORTIONS OF NORTHERN
WI IN NWS LA CROSSE CWA...THESE STORMS LOST PUNCH WHILE MOVING NORTH
AWAY FM GREATER MLCAPES OVER 1000 J/KG TO THE SOUTH AND WEST CLOSER
TO MAIN SFC WARM FRONT. DECENT AREA OF LIGHT TO MODERATE RAIN STILL
OVER THE WEST AS THE SHRA/TSRA ARE BEING DRIVEN BY SHORTWAVE LIFTING
OVER WESTERN LK SUPERIOR AND ASSOCIATED H85-H7 MOISTURE TRANSPORT.
HAD REPORT VIA SOCIAL MEDIA OF NEAR A THIRD OF AN INCH IN THE
IRONWOOD AREA THIS EVENING. FOLLOWING POCKET OF HIGHER H7-H5 RH OFF
RUC/NAM INDICATES SHORTWAVE AND LIFT WILL LIFT TOWARD SCNTRL LK
SUPERIOR OVERNIGHT TONIGHT. SINCE ISOLD SHRA/TSRA ARE OCCURRING OVR
CNTRL WI ON SOUTHERN EDGE OF BETTER FORCING AND THIS IS FORECAST TO
LIFT OVER CNTRL CWA...HAVE EXPANDED THE EASTERN EDGE OF SLIGHT CHANCE
POPS INTO DICKINSON AND MARQUETTE COUNTIES OVERNIGHT. 00Z HRRR COMPOSITIVE
REFLECTIVITY FORECAST ALSO SHOWING SIMILAR SCENARIO. CANNOT RULE OUT
ISOLD TSRA WITH BRIEF HEAVY DOWNPOUR AS 1-6KM MUCAPE IS STILL A FEW
HUNDRED J/KG AND PWATS REMAIN AROUND 175 PCT OF NORMAL.
STEADY SOUTH WIND AND INCREASING LOW-LEVEL MOISTURE WITH DWPNTS AOA
60 DEGREES HAS RESTRICTED TEMP FALL THUS FAR. NUDGED OVERNIGHT LOW
TEMPS UPWARD BY A FEW DEGREES...ESPECIALLY CLOSER TO LK SUPERIOR
WHERE THE SOUTH WINDS PROVIDE A BIT OF DOWNSLOPE WARMING.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 448 PM EDT FRI JUN 27 2014
THIS AFTERNOON INTO TONIGHT...THIS AFTERNOON A COUPLE SHORTWAVES TO
NOTE ARE SHOWING UP ON BOTH WV LOOP AND THE RUC ANALYSIS. THE FIRST
WAVE IS PUSHING SLOWLY THROUGH THE WESTERN HALF OF THE U.P. WHILE
THE NEXT ONE OVER SOUTHERN MN IS DIRECTLY BEHIND IT...BUT SLIGHTLY
WEST OF THE TRACK OF THE FIRST WAVE. THE FIRST WAVE HAS BEEN
TOUCHING OFF A FEW SHOWERS AND A COUPLE ISOLATED THUNDERSTORMS OVER
NORTHERN WI AND WESTERN UPPER MI...BUT THE OVERALL TREND FOR THE
PRECIP HAS BEEN TO VERY SLOWLY DIMINISHING. HI RES MODEL ANALYSIS
SHOWS THIS TREND IS EXPECTED TO CONTINUE INTO THE LATE AFTERNOON
HOURS. THIS MAKES SENSE AS MOST OF THE INSTABILITY AND BETTER
MOISTURE SOURCE IS MAINLY SOUTH AND WEST OF THE U.P. WITH ONLY MINOR
FORCING ASSOCIATED WITH THE WAVE AS IT PUSHES THROUGH THE WESTERN
U.P. ONCE THE FIRST WAVE PUSHES OUT OF THE U.P. LATE THIS AFTERNOON
THERE WILL BE A BIT OF A LULL IN THE PRECIP BEFORE THE SECOND WAVE
MOVES IN. THIS WAVE IS EXPECTED TO PUSH INTO THE WESTERN HALF OF THE
U.P. AROUND 00Z/28...THEREFORE...HAVE KEPT THE INCREASED CHANCE OF
SHOWERS AND THUNDERSTORMS IN THE FAR WEST AROUND THAT TIME AND
LINGERING THROUGH ABOUT 10Z. MUCH OF THE RAINFALL WILL OCCUR OVER
WESTERN LAKE SUPERIOR AND OVER THE ARROWHEAD OF MN...CLOSER TO THE
BETTER FORCING. HAVE ADDED PATCHY FOG IN THE FORECAST FOR MAINLY THE
SOUTH CENTRAL AND WEST HALF...MAINLY NEAR THE WI BORDER
OVERNIGHT...DUE LARGELY TO THE INCREASED SURFACE MOISTURE FROM RAIN
THIS AFTERNOON AND DUE TO THE OVERALL INCREASING DEWPOINTS OVER THE
AREA.
SATURDAY...AS THE AFOREMENTIONED SHORTWAVE CONTINUES TO LIFT TO THE
NORTH OVER WESTERN LAKE SUPERIOR...EXPECT LINGERING CHANCES OF
SHOWERS AND THUNDERSTORMS IN THE MORNING OVER THE WESTERN LAKE AND
OVER FAR WESTERN UPPER MI. THE MAIN TROUGH AND ASSOCIATED SURFACE
LOW OVER THE NORTHERN PLAINS ARE PROGGED TO INTENSIFY ALLOWING A
RIDGE OVER MUCH OF THE EASTERN U.S. TO STRENGTHEN AS WELL. THIS WILL
HELP THE WESTERN EDGE OF THE RIDGE TO REMAIN IN PLACE OVER THE
EASTERN HALF OF THE U.P. THROUGH MUCH OF THE DAY SATURDAY...KEEPING
MUCH OF THE PRECIPITATION CONFINED TO THE FAR WESTERN HALF OF THE
U.P. DRIER AIR WILL LIKELY LINGER OVER THE EAST HALF UNDER THE
INFLUENCE OF THE HIGH...WHICH WILL ALSO HELP REDUCE ANY CHANCE OF
SHOWERS AND THUNDERSTORMS. BY LATE SATURDAY AFTERNOON THE UPPER
LEVEL RIDGE AND UPPER LEVEL TROUGH WILL SHIFT SLOWLY EASTWARD. THIS
WILL ALLOW SHOWERS AND THUNDERSTORMS TO AGAIN INCREASE IN COVERAGE
OVER THE ARROWHEAD OF MN...WESTERN LAKE SUPERIOR AND OVER THE FAR
WESTERN U.P. AS MOISTURE/FORCING INCREASES OVER THOSE AREAS AS SHOWN
BY ANALYZING 1000-500RH ALONG WITH DEEP LAYER QCONV.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 448 PM EDT FRI JUN 27 2014
MAIN FCST CONCERNS DURING THE LONGER TERM PERIOD ARE FOCUSED ON THE
CHANCE FOR SHOWERS/TS LATE SAT THRU MON AND THE POTENTIAL FOR ANY
SEVERE STORMS AS A STRONG SW FLOW BTWN HI PRES OFF THE E COAST AND
DEEP LO PRES IN SCENTRAL CANADA ADVECTS PLENTY OF MOISTURE INTO THE
UPR LKS. TEMPS THRU MON WL BE RUNNING ABV NORMAL BEFORE COOLER AIR
RETURNS ON TUE FOLLOWING COLD FROPA ATTENDANT TO SFC/CLOSED LO
SHIFTING E INTO ONTARIO.
SAT NIGHT INTO SUNDAY...UPR MI WL BE SITUATED IN THE WARM SECTOR OF
MID-LVL TROF AND DEVELOPING CLOSED LOW NEAR LK WINNIPEG AND WILL BE
UNDER THE INFLUENCE OF A WARM...HUMID SSW FLOW BTWN THIS LO AND
NEARLY STATIONARY HI PRES OFF THE E COAST. THIS PATTERN WILL SET THE
STAGE FOR TSRA DEVELOPMENT...ESPECIALLY LATE SAT NIGHT INTO SUNDAY
AS MODELS ADVERTISE A VIGOROUS SHORTWAVE LIFTING NE FROM THE PLAINS
INTO THE UPPER GREAT LAKES REGION. THE BEST CHC FOR SHOWERS/TS LATE
SAT NIGHT SHOULD BE OVER THE WRN CWA CLOSER TO THE CLOSED LOW AND
ITS ASSOC FRONTAL BOUNDARY APPROACHING FROM THE WEST. HOWEVER...SOME
OF THE MODELS INDICATE THE ACCOMPANYING DYNAMIC SUPPORT (Q-VECT
CONV) MAY NOT BE IN SYNC WITH H85 THETA E ADVECTION. HOWEVER
CONSIDERING THE MOIST AND UNSTABLE AIRMASS IN PLACE...THE PASSAGE OF
THE SHORTWAVE AND THE ACCOMPANYING FRONTAL BOUNDARY MOVING INTO THE
AREA DID BUMP UP POPS TO LIKELY OVER THE WEST LATE SAT NIGHT AND
ACROSS MUCH OF THE CWA ON SUNDAY. SPC HAS THE WRN THIRD OF CWA IN A
SLIGHT RISK FOR SVR ON DAY3 (SUNDAY). SINCE THE 12Z ECMWF AND GFS
SHOW MLCAPE VALUES RISING AOA 1000 J/KG WITH DEEP LAYER SHEAR
INCREASING TO AROUND 30 KT BY MIDDAY SUNDAY WILL CONTINUE TO MENTION
POSSIBLE SVR STORMS IN THE HWO OVER PRIMARILY THE WEST HALF FOR SAT
NIGHT INTO SUNDAY. DAYTIME MAX TEMPS ON SUN SHOULD RISE INTO THE 80S
AWAY FM THE LK MI COOLING WITH H85 TEMPS FCST ARND 17C.
SUN NIGHT...SOME OF THE MODELS...PARTICULARLY THE ECMWF SUGGEST
THERE COULD BE A BREAK IN CONVECTION ESPECIALLY LATER SUN NIGHT WITH
A LACK OF SHORTWAVES MOVING THROUGH THE AREA AND DRYING/SUBSIDENCE
HINTED BY MODEL SNDGS. FOG COULD BECOME MORE OF A FACTOR SUN NIGHT
WITH WARM HUMID AIRMASS STILL IN PLACE AND A POSIBLE BREAK IN PCPN.
THE LOWEST TEMPS WILL BE MOST LIKELY DOWNWIND OF THE COOLING
INFLUENCE OF LK MI...WHERE FOG MAY ALSO ADVECT IN OFF THE LK.
MON INTO MON NIGHT...AS THE CLOSED LOW OVER SRN MANITOBA
DRIFTS INTO NW ONTARIO...MODELS SHOW THAT THE ASSOCIATED COLD FRONT
EXTENDING FROM THE SFC LOW WILL MOVE SLOWLY E ACROSS UPR MI. MODEL
CONSENSUS SHOWS THE FRONT MOVING THROUGH WRN UPR MI IN THE MORNING
WITH THE PASSAGE OF ONE NRN PLAINS SHORTWAVE...THEN THE FRONT STALLS
TEMPORARILY OVER CENTRAL UPR MI MON AFTERNOON BEFORE ANOTHER
STRONGER NRN PLAINS SHORTWAVE PUSHES THE FRONT EAST OF THE CWA BY
LATE MON EVENING/EARLY TUE MORNING. MODERATE MID-LVL Q-VECT CONV AND
MOISTENING AHEAD OF THIS SECONDARY SHORTWAVE SHOULD INITIATE MORE
WIDESPREAD SHRA/TSRA OVER CENTRAL AND ERN PORTIONS OF THE CWA MON
EVENING. DRYING IN THE WAKE OF THE MONDAY/S COLD FROPA AS WELL AS
NOCTURNAL COOLING WL RESULT IN DIMINISHING CHCS FOR PCPN LATE MON
NIGHT.
TUE AND WED... ALTHOUGH DRIER AIR WL REMAIN IN PLACE...MOST OF THE
EXTENDED MODELS HINT THAT A SERIES OF SHRTWVS MAY ROTATE AROUND
THE CLOSED LOW DRIFTING E THRU ONTARIO AND IMPACT THE UPR LKS. IN
THE PRESENCE OF LLVL CYCLONIC FLOW OR ESPECIALLY IF TIMED WITH
DIURNAL HEATING THESE SHORTWAVES COULD TRIGGER SOME ISOLD SHOWERS.
MODELS ADVERTISE MUCH COOLER AIR (5-8C OFF 00Z ECMWF) WITH THE
PASSAGE OF THESE SHORTWAVES SO BLO NORMAL TEMPS SHOULD BE THE RULE
TUE INTO THU.
THU AND THE 4TH OF JULY...BOTH THE ECMWF AND GFS INDICATE STRONG SFC
RDGG BEGINNING TO BUILD IN FM THE WEST SO HAVE BETTER CONFIDENCE FOR
DRY FCST TOWARD THE END OF THE WEEK. TEMPS BY THE 4TH WILL BEGIN TO
REBOUND BUT MAY STILL BE SLIGHTLY BLO NORMAL VALUES WITH HIGHS
LIKELY IN THE LOWER TO MID 70S ACROSS MUCH OF THE AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 110 AM EDT SAT JUN 28 2014
EXPECT SHRA AND PERHAPS AN ISOLD TSRA TO AFFECT KCMX EARLY THIS
MORNING...WITH JUST A SLIM CHANCE OF A SHRA/TSRA AT KIWD AND KSAW.
CONDITIONS SHOULD STAY VFR THOUGH. AFTER THE CHANCE OF RAIN ENDS
LATER THIS MORNING...EXPECT MAINLY QUIET WEATHER THROUGH MUCH OF
TODAY WITH SCT MID CLOUDS. NEXT CHANCE OF SHRA/TSRA WILL RETURN TO
KIWD LATER THIS EVENING. HAVE INCLUDED MENTION OF LOW-LEVEL WIND
SHEAR AS LOW-LEVEL JET IS OVERHEAD THIS MORNING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 448 PM EDT FRI JUN 27 2014
HIGH PRESSURE WILL DOMINATE INTO SATURDAY KEEPING WINDS GENERALLY
LIGHT OVER LAKE SUPERIOR...LESS THAN 25 KTS. SUNDAY INTO MONDAY AN
AREA OF LOW PRESSURE WILL APPROACH THE UPPER GREAT LAKES REGION
BRINGING SOUTHERLY WINDS INTO THE AREA...YET WIND SPEEDS WILL STILL
REMAIN 25 KNOTS OR LESS. PATCHY FOG WILL BE POSSIBLE OVER MUCH OF
THE LAKE INTO MONDAY NIGHT. HIGH PRESSURE WILL BUILD BACK INTO THE
REGION BY WEDNESDAY KEEPING WINDS GENERALLY LESS THAN 15 KNOTS OVER
LAKE SUPERIOR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...JLA
SHORT TERM...KEC
LONG TERM...VOSS
AVIATION...JLA
MARINE...KEC
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
337 PM CDT SAT JUN 28 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 337 PM CDT SAT JUN 28 2014
EARLY AFTERNOON WATER VAPOR IMAGERY TOGETHER WITH RAP 500MB HEIGHTS
AND WINDS SHOWED A NEGATIVELY TILTED TROUGH ACROSS THE EASTERN
DAKOTAS DOWN THROUGH THE NE/IA BORDER. A FEW EMBEDDED VORTICITY
MAXIMA WITHIN THIS TROUGH WILL LIFT NORTH NORTHEAST AND PROVIDE
UPPER LEVEL ASCENT NEEDED FOR SHOWERS AN THUNDERSTORMS THIS
AFTERNOON. AT THE SURFACE...A NORTH/SOUTH ORIENTED WARM FRONT WAS
LOCATED ACROSS WESTERN/CENTRAL MN...AS EVIDENT BY THE SOUTH
SOUTHEASTERLY WINDS AND LOWER 70 DEWPOINTS ON THE EAST SIDE OF THE
FRONT...AND SOUTH SOUTHWESTERLY WINDS WITH LOW 60 DEWPOINTS ON THE
WEST SIDE OF THE FRONT. CONVERGENCE ALONG THIS BOUNDARY LED TO A
LINE OF SHOWERS AND THUNDERSTORMS EXTENDING NORTHWEST MN DOWN
THROUGH CENTRAL IOWA.
RAP FORECAST SOUNDINGS AHEAD OF THIS LINE OF CONVECTION SHOW
GENERALLY SOUTHERLY WINDS THROUGHOUT THE TROPOPAUSE...SO LITTLE IN
THE WAY OF DEEP LAYER DIRECTION SHEAR. HOWEVER...CHANGES IN SPEED
WITHIN THE LOWER LEVEL OF THE ATMOSPHERE RESULTED IN 15 TO 25KTS
OF 1KM SHEAR. MLCAPE WAS 1500 TO 2000J/KG...WHILE THE 0-3KM CAPE
AROUND 50J/KG. GIVEN THE AFOREMENTIONED PARAMETERS...A SEVERE
THUNDERSTORM WATCH IS IN EFFECT UNTIL 9PM CDT. THE HIRES MODELS
CONTINUE TO SHOW THE CONVECTION WEAKENING LATER THIS EVENING AS IT
CROSSES INTO WESTERN WI AND OUTRUNS THE UPPER LEVEL FORCING...BUT IN
THE MEAN TIME A FEW STRONG WINDS COULD MIX DOWN WITH THE HEAVIER
PRECIP CORES...SO FEEL THAT DAMAGING WINDS ARE THE PRIMARY THREAT.
LOW LCLS WOULD BE FAVORABLE FOR A BRIEF TORNADO...BUT AT THIS TIME
HODOGRAPHS WOULD NOT SUPPORT ANYTHING MORE THAN THAT.
THIS PRECIP WILL CONTINUE NORTHEAST OVERNIGHT AS A DRY SLOT DEVELOPS
IN IS WAKE. SOUTHWESTERLY WINDS WILL APPROACH WIND ADVISORY
CRITERIA...BUT THE STRONGEST WINDS SHOULD BE WEST OF THE CWA. THIS
DRY SLOT IS CHARACTERIZED BY STEEP MID LEVEL LAPSE RATES...WHICH
WILL MOVE ACROSS THE REGION ON SUNDAY. THE WARM MOIST BOUNDARY LAYER
WILL STILL BE IN PLACE...SETTING THE STAGE FOR AFTERNOON CAPE VALUES
NEAR 3000J/KG. DEEP LAYER SHEAR WILL INCREASE DURING THE AFTERNOON
TO AROUND 50KTS...BUT THE ONE LIMITING FACTOR FOR SEVERE WEATHER IS
THE LACK OF LOW LEVEL CONVERGENCE...WHICH IS BETTER TO THE SOUTH
ACROSS IOWA. THEREFORE WE STILL HAVE A CONDITIONAL THREAT FOR SEVERE
WEATHER...BUT IT WILL DEPEND ON WHETHER OR NOT THE STORMS ARE ABLE
TO FIRE IN SOUTHERN/CENTRAL MN. IF THEY DO...EXPECT THEM TO QUICKLY
TURN SEVERE...WITH HIGH END SEVERE POSSIBLE...MEANING HAIL OVER 2
INCHES...AND WINDS IN EXCESS OF 75MPH. AS OF NOW...THE BEST CHANCE
IS IN SOUTHEASTERN MN...GENERALLY ALONG A LINE FROM FAIRMONT MN
THROUGH MANKATO MN TO RED WING MN.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 337 PM CDT SAT JUN 28 2014
LONG TERM ANALYSIS/FORECASTING CUT SHORT TODAY WITH BOTH
FORECASTERS FOCUSED ON SHORT TERM DUTIES. OVERALL...THE LONG TERM
PERIOD BEGINS WITH A MASSIVE UPPER LOW OVER SOUTHERN MANITOBA.
THE FA WILL BE ON THE SOUTHERN FRINGE OF STRONG WESTERLIES EARLY
IN THE PERIOD. MODEL SOLUTIONS POINT TO MUCH OF THE CONVECTION BY THE
TIME SUNDAY NIGHT ARRIVES WILL BE OVER THE FAR SOUTHERN AND
EASTERN FA. SOME BRIEF DRYING WILL OCCUR DURING THE NIGHT...BUT A
SHORT WAVE ROTATING AROUND THE UPPER LOW WILL BRING MORE SHOWERS
AND THUNDERSTORMS FROM THE CENTRAL PLAINS INTO SOUTHERN MINNESOTA
AND ADJOINING AREAS OF WESTERN WI BY MONDAY MORNING. AS THE UPPER
LOW MOVES INTO WESTERN ONTARIO DURING THE DAY ON MONDAY...THE
SOUTHERN ACTIVITY WILL SLIDE EAST WHILE SCATTERED SHOWERS BEGIN
MOVING IN FROM THE NORTHWEST. THE COLD TROUGH ALOFT WILL BE OVER
THE REGION ON TUESDAY WITH SCATTERED SHOWERS EXPECTED ALONG WITH
HIGHS ONLY IN THE MIDDLE 60S TO LOWER 70S. WEDNESDAY WILL BE
ANOTHER COOL DAY WITH SIMILAR HIGHS AND YET ANOTHER THREAT FOR
SHOWERS AS THE FINAL SHORT WAVE ROTATES THROUGH. THURSDAY IS OUR
ONLY SOLID DRY DAY BEFORE THE UPPER FLOW TURNS MORE WESTERLY
ALLOWING SHORT WAVE ENERGY IN FROM THE PLAINS. THIS WILL LIKELY
LEAD TO SCATTERED SHOWERS AND THUNDERSTORMS FOR FRIDAY (4TH OF
JULY) AND SATURDAY. HIGH TEMPERATURES WILL REBOUND LATE IN THE
WEEK WITH SEASONAL HIGHS IN THE LOWER TO MIDDLE 80S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1200 PM CDT SAT JUN 28 2014
TWO ISSUES AT TAF ISSUANCE. FIRST IS THE MVFR CEILINGS THAT
STRETCH FROM KAXN TO KRWF ON EASTWARD. THE CEILINGS ARE SLOWLY
LIFTING AS MIXING INCREASES DUE TO DEEPENING LOW PRESSURE OVER THE
DAKOTAS. GRADUALLY BROUGHT ALL SITES UP TO VFR DURING THE
AFTERNOON. THE SECOND ISSUE IS THE FINE LINE OF CONVECTION ALONG A
PREFONTAL CONVERGENCE ZONE NEAR KAXN TO KRWF. LATEST HRRR AND 12Z
HOPWRF MEMBERS ARE IN GOOD AGREEMENT ON CONVECTION INCREASING IN A
NORTH-SOUTH LINE DURING THE AFTERNOON AS IT HEADS SLOWLY EAST.
TIMED THE CONVECTION PER THE AFOREMENTIONED SOLUTIONS. THE MOST
ROBUST ACTIVITY AFFECTS THE TWIN CITIES IN THE 22Z-24Z TIME FRAME.
THE CONVECTION WILL BE MOVING ACROSS WEST CENTRAL WI EARLY THIS
EVENING. SOME CLEARING IN THE WAKE OF THE STORMS TONIGHT COUPLED
WITH THE MOIST LOW LEVELS AND DIMINISHING WIND WILL ALLOW MVFR OR
LOWER CEILINGS TO DEVELOP. CONFIDENCE IS HIGHEST ACROSS EASTERN MN
AND WEST CENTRAL WI WHERE AFTERNOON/EVENING SHOWERS AND
THUNDERSTORMS WILL OCCUR...MOISTENING THE BOUNDARY LAYER EVEN
MORE BEFORE SUNSET. PRELIMINARY LOOK AT SUNDAY SUGGESTS MUCH OF THE
CONVECTION MAY BE JUST SOUTH OF KRWF-KMSP-KEAU. WINDS THIS
AFTERNOON SSE 15-20 KNOTS GUSTING 25-30 KNOTS. WINDS SUNDAY SSW
15-20 KNOTS GUSTING 25-30 KNOTS.
KMSP...CEILINGS LIFTING TO VFR EARLY THIS AFTERNOON. SEVERAL WAVES
OF CONVECTION EXPECTED AT THE AIRFIELD IN THE 22Z-24Z TIME PERIOD
WITH GUSTY SW WINDS TO 40 KNOTS AND SMALL HAIL. MVFR CEILINGS ARE
FORECAST FOR LATE TONIGHT AND EARLY SUNDAY WITH VFR THEREAFTER.
/OUTLOOK FOR KMSP/
SUN NITE...VFR. WINDS SW 10KTS.
MON...VFR. WINDS W 10-15KTS.
TUE...VFR WITH MVFR CIGS POSSIBLE. WINDS NW 20KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...JRB
LONG TERM...RAH
AVIATION...RAH
AREA FORECAST DISCUSSION
NWS DULUTH MN
106 PM CDT SAT JUN 28 2014
.UPDATE...
ISSUED AT 103 PM CDT SAT JUN 28 2014
SHORT TERM FOCUS ON TIMING OF THUNDERSTORMS AND SEVERE POTENTIAL
THROUGH TONIGHT.
CURRENT SATELLITE/RADAR IMAGERY SHOWS A WELL DEFINED LOW
CIRCULATION OVER THE BISMARK AREA...WITH CONVECTION BEGINNING TO
INITIATE ALONG A LINE FROM GENERALLY FARGO...THROUGH THE BRAINERD
AREA...AND WESTERN TWIN CITIES METRO. LATEST RUC MESO- ANALYSIS
DEPICTS THE DEVELOPING STORMS ARE ALONG AN AXIS OF INCREASING ML
CAPE/ERODING CIN...ALONG WITH STRONG SHEAR. EXPECT THIS LINE OF
STORMS TO INCREASE IN COVERAGE AND INTENSITY THROUGH THE
AFTERNOON...WHILE THE CORRIDOR OF FAVORABLE INSTABILITY GRADUALLY
SHIFTS EAST. THE LATEST HRRR SEEMS TO HAVE A GOOD HANDLE ON THE
CURRENT SITUATION AND SUGGESTS THE LEADING EDGE OF THE LINE OF
STORMS REACHES THE AREAS OF KINL...TO KHIB...AND EXTENDS SOUTH
ALONG THE I-35 CORRIDOR AROUND 00Z...BECOMING WIDESPREAD OVER MUCH
OF THE DLH CWA BY 03Z.
THE MAIN THREAT FOR THESE STORMS REMAINS HEAVY DOWNPOURS/LOCALIZED
FLOODING...POTENTIAL FOR DOWNBURSTS/WIND DAMAGE...AND A POSSIBLE
TORNADO. THERE IS A MINIMAL THREAT FOR LARGE HAIL DUE TO FREEZING
LEVELS AROUND 14 KFT
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 420 AM CDT SAT JUN 28 2014
AN AREA OF SHOWERS WITH EMBEDDED THUNDERSTORMS IS MOVING ACROSS
NORTHERN MINNESOTA THIS MORNING. THIS AREA OF CONVECTION IS WITHIN
A BROAD AREA OF WARM MOIST ADVECTION...WITH A LOW LEVEL JET OF 35 TO
45 KNOTS EXTENDING FROM TEXAS NORTH UP ACROSS THE PLAINS TO NORTHERN
MINNESOTA. ANOTHER AREA OF SHOWERS AND THUNDERSTORMS IS GRADUALLY
DECAYING OVER EASTERN SOUTH DAKOTA...EXTENDING INTO EASTERN
NEBRASKA. EARLY THIS MORNING THE CURRENT AREA OF STORMS SHOULD EXIT
OFF TO THE NORTH...LEAVING OUR NORTHERN MINNESOTA COUNTIES WITH JUST
SOME LINGERING SHOWERS FOR MOST OF OUR MORNING HOURS. THE
CONVECTION NOW OVER SOUTH DAKOTA IS EXPECTED TO DECAY TO MAINLY MID
CLOUDS AND A FEW SHOWERS BEFORE IT GETS HERE. WILL BE WATCHING
THESE TRENDS CLOSELY. THEN...THIS AFTERNOON NEW CONVECTION IS
EXPECTED TO FORM IN THIS DEEP MOISTURE PLUME...AND THEN MOVE ACROSS
THE AREA TONIGHT. THIS AFTERNOON AND EVENING PLENTY OF INSTABILITY
IS EXPECTED...WITH HIGHS NEAR 80 AND DEWPOINTS IN THE 60S. CAPE
VALUES WILL GENERALLY BE AROUND 1000J/KG...WITH BULK SHEAR VALUES OF
30-40KTS...MAINLY ACROSS THE SOUTHWESTERN PORTIONS OF THE FORECAST
AREA. WITH THIS DEEP WARM AIRMASS IT APPEARS THAT WIND WILL BE OUR
MAIN THREAT. WITH WET BULB ZERO HEIGHTS UP OVER 12KFT...HAIL SHOULD
BE HARDER TO GET. PRECIPITABLE WATER VALUES WILL BE UP OVER 1.5
INCHES...WHICH IS APPROACHING 200 PERCENT OF NORMAL FOR THIS TIME OF
YEAR. THIS DOES HIGHLIGHT MORE OF A FLASH FLOOD RISK FOR THIS
AFTERNOON AND TONIGHT AS THE CONVECTION ROLLS ACROSS THE AREA.
HOWEVER...RECENT RAINFALL IS RELATIVELY LOW...WITH 7 DAY PRECIP
ACCUMULATIONS GENERALLY LESS THAN AN INCH WITH MOST OF THAT 7 DAYS
AGO. THUS...OUR FLASH FLOOD GUIDANCE IS MAINLY IN THE 2-3 INCH IN
6 HOURS RANGE...WITH THE LOWEST VALUES OVER NORTHWEST WISCONSIN.
THUS...WHILE THE THREAT FOR FLASH FLOODING IS THERE...AM THINKING IT
WILL TAKE TRAINING OF STORMS AND/OR MULTIPLE ROUNDS OF STORMS FOR
THE SAME LOCATION BEFORE FLASH FLOODING DEVELOPS. THUS...HAVE HELD
OFF FOR NOW ON ANY FLASH FLOOD WATCH...AND WE CAN MONITOR HOW THE
CONVECTION MOVES IN THIS AFTERNOON BEFORE MAKING THE CALL ON THAT.
AM STILL CARRYING LIKELY OR CATEGORICAL POPS FOR TONIGHT. TEMPS TO
REMAIN MILD TONIGHT WITH LOWS IN THE LOW 60S MOST AREAS.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 420 AM CDT SAT JUN 28 2014
THE FIRST HALF OF THE FORECAST PERIOD WILL BE UNDER THE INFLUENCE OF
A LARGE UPPER LEVEL CLOSED LOW OVER THAT WILL SLOWLY MOVE ACROSS
SOUTHERN CANADA. SERIES OF SHORTWAVES WILL ROTATE SOUTH AROUND THE
LOW AND BRING PERIODS OF SHOWERS AND MAYBE THUNDERSTORMS TO THE
NORTHLAND THROUGH TUESDAY...BUT BY TUESDAY THEY SHOULD BE WIDELY
SCATTERED. BY WEDNESDAY THE UPPER LOW AND ITS ASSOCIATED TROF WILL
HAVE MOVED EAST AND HAVE BEEN REPLACE BY A RIDGE OF HIGH PRESSURE
WHICH WILL BRING SOME DRY WEATHER FEW A COUPLE DAYS. BY FRIDAY
ANOTHER LOW PRESSURE WILL BE ADVANCING TOWARD THE AREA. AN INCREASE
IN MOISTURE IN THE SOUTHERLY FLOW AND A COLD FRONT WILL PROVIDE A
CHANCE FOR SOME SHOWERS AND THUNDERSTORMS INTO THE WEEKEND. THE
ECMWF IS PRETTY HEAVY OF THE PCPN COMPARED TO THE GFS ESPECIALLY
LATE THURSDAY NIGHT...BUT THIS CAN BE EXPECTED IN CONVECTIVE QPF.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1236 PM CDT SAT JUN 28 2014
A STRONG PUSH OF WARM MOIST UNSTABLE AIR WILL CONTINUE TODAY
ACROSS THE NORTHLAND WITH GUSTY SOUTH WINDS AND A LINE OF
CONVECTION DEVELOPING TO THE SW AND MOVING E/NEWD THROUGH THE
REGION. TIMING OF SHOWERS AND STORMS APPEARS TO BE LATE THIS
AFTERNOON AND THROUGH THE EVENING FROM WSW TO THE EAST. AFTER
SHOWERS AND STORMS DEPART TO THE EAST LATE TONIGHT...COULD SEE
PATCHY FOG DEVELOP AT DLH AND HIB. CONDITIONS BECOME VFR SUNDAY
MORNING AND WINDS INCREASE AGAIN OUT OF THE SW BEFORE 18Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 62 78 59 77 / 70 20 30 30
INL 67 78 59 72 / 80 30 40 60
BRD 68 80 61 78 / 70 20 20 20
HYR 69 82 63 80 / 70 30 40 30
ASX 65 81 62 78 / 70 40 40 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...DENSE FOG ADVISORY UNTIL 4 AM CDT SUNDAY FOR LSZ140>145.
&&
$$
UPDATE...GRANING
SHORT TERM...LE
LONG TERM...CLC
AVIATION...BJT
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1200 PM CDT SAT JUN 28 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 401 AM CDT SAT JUN 28 2014
MAIN SHORT TERM CONCERNS CONTINUE TO DEAL WITH REDEVELOPMENT OF
RAIN/THUNDER AND SEVERE WEATHER THREAT.
LATEST SPC MESOANALYSIS SHOWS LAYERED DIFFERENTIAL VORTICITY
ADVECTION LIFTING NORTH ACROSS NORTHERN MN AS SHORT WAVE EXITS THE
AREA. SOME RESIDUAL SHOWERS REMAIN IN WAA PATTERN OVER THE
NORTHWEST CWA...BUT THESE SHOULD GRADUALLY END AS WELL. ALSO..THE
MCS THAT MOVED ACROSS NEBRASKA/EASTERN SOUTH DAKOTA IS WEAKENING IN
LINE WITH VARIOUS HIRES SOLUTIONS FOR THIS MORNING. WILL MAINTAIN
SOME CHANCE POPS TO THE WEST EARLY THIS MORNING...THEN TREND LIKELY
POPS ACROSS THE WEST BY 18Z. WE ALSO MAINTAIN STRONG PRESSURE
GRADIENT OVER THE AREA TODAY. THIS WILL CONTINUE THE BREEZY SE-S
WINDS GUSTING OVER 25KTS IN THE WEST.
WE STILL MAINTAIN CONTINUOUS MOISTURE FEED NORTH WITH PW`S
INCREASING CLOSE TO 2 INCHES AS THE UPPER TROUGH SWINGS EAST.
HAVE CLOSE TO AN INCH OF QPF IN THE GRIDS FOR THE THIS
AFTERNOON/TONIGHT PERIOD ACROSS CENTRAL AND EASTERN AREAS. WE WILL
HAVE TO MONITOR THE HYDRO SITUATION NONETHELESS...AS PRECIP RATES
WILL BE HIGH IN ANY ORGANIZED ACTIVITY..
SEVERE WEATHER THREAT WILL DEPEND ON CLOUDS COVER/DESTABILIZATION
RATE INTO THE AFTERNOON. EXPECTING A FAIR AMOUNT OF CLOUD COVER SO
IT MAY LIMIT HIGHER CAPE POTENTIAL. DEEP LAYER SHEAR INCREASES TO
35-45KTS THIS AFTERNOON AND MID LEVEL LAPSE RATES INCREASE TO AROUND
7C/KM. WIND AND HAIL WILL BE A THREAT...MAINLY ACROSS THE EASTERN
PORTION OF THE CWA THIS AFTERNOON/TONIGHT.
THE TROUGH SWINGS EAST OVERNIGHT AND WILL TRAIL OFF POPS FROM WEST
TO EAST DURING THE NIGHT. CLOUDS WILL REMAIN FOR THE MOST PART.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 401 AM CDT SAT JUN 28 2014
MOST OF THE CONVECTION WILL CLEAR THE CWA BY EARLY SUNDAY MORNING
AS THE TROUGH PUSHES EAST. MUCH DRIER AIR ALOFT WILL BE PUSHING IN
SO AM ANTICIPATING QUITE A BIT OF SUN IN THE MORNING AND EARLY
AFTERNOON. MEANWHILE...A MID LEVEL SPEED MAX EJECTING EAST FROM
THE ROCKIES WILL ACCELERATE AS IT APPROACHES THE UPPER MIDWEST DUE
TO A BUILDING RIDGE ACROSS THE SOUTHERN PLAINS AND A DEEPENING
CYCLONE ACROSS SOUTHERN CANADA. THIS ZONAL FLOW SPEED MAX WILL
INTERACT WITH A MODERATE TO VERY UNSTABLE AIRMASS IN PLACE OVER
CENTRAL/SOUTHERN MN AND NORTHERN IA AND SHOULD PRODUCE RAPIDLY
DEVELOPING DISCRETE SUPERCELLS BY EARLY OR MID AFTERNOON OVER
SOUTHWEST/SOUTH CENTRAL MN...POSSIBLY INTO EAST CENTRAL MN. THERE
IS STILL A FAIR AMOUNT OF UNCERTAINTY OF PRECISELY WHERE THIS
DEVELOPMENT WILL OCCUR GIVEN THE TREND FOR MODELS TO PUSH THIS
ACTIVITY SOUTH WITH SEEMINGLY EACH RUN. DID REDUCE POPS ACROSS THE
MAJORITY OF THE AREA...EXCEPT OVER SOUTHERN MN FOR THIS TREND.
HOWEVER...THIS IS NOT TO SAY STORMS ARE NOT POSSIBLE FURTHER
NORTH INTO CENTRAL MN AND NORTHWEST WI...THEY WILL JUST BE MORE
ISOLATED. ALL MODES OF SEVERE WEATHER CAN BE EXPECTED...INCLUDING
TORNADOES. IN FACT...THE TOGGIE TOR PROBS OF EQ 1 AND EQ 2 SHOW
HIGH PROBABILITIES /50 TO 80 PERCENT/ ACROSS SOUTHERN MN AND
WESTERN WI. SIG TOR PARAMETERS ARE ALSO WELL INTO THE FAVORABLE
RANGE. THUS THE SITUATION BEARS WATCHING...ESPECIALLY IN THE
DISCRETE SUPERCELL PHASE SUNDAY AFTERNOON. THE NORTHERN AND
CENTRAL PORTIONS OF THIS ACTIVITY WILL CONGEAL INTO A FORWARD
PROPAGATING MCS AND PUSH INTO WI DURING THE EVENING HOURS WITH A
MAIN CONCERN FOR DAMAGING WINDS. THE SOUTHERN THIRD OF THIS
CONVECTION MAY BECOME ANCHORED ON A WARM FRONT AND TRAIN OVER
NORTHERN IA AND/OR FAR SOUTHERN MN WITH A THREAT FOR CONTINUED
SEVERE WEATHER...VERY HEAVY RAIN AND FLASH FLOODING.
ANOTHER COMPLEX MAY FORM OVER NORTHWEST IA/NORTHEAST NE OVERNIGHT
AS THE LLJ STRENGTHENS. THERE IS EVEN MORE UNCERTAINTY WHERE THIS
BATCH WILL TRACK AND WILL DEPEND LARGELY ON THE FIRST MCS. 00Z
RUNS DO PUSH IT NORTH INTO SOUTHERN MN AND WESTERN WI BY MONDAY
MORNING SO FELT COMPELLED TO INCREASE POPS DURING THIS TIME.
DRY SLOT WILL FINALLY PUSH IN MONDAY AFTERNOON BEFORE THE MOIST
CYCLONIC FLOW SAGS SOUTH MONDAY EVENING AND PERSISTS THROUGH
TUESDAY. CONSIDERABLE CLOUDINESS AND SCATTERED SHOWERS LOOK LIKE A
DECENT BET ALONG WITH MUCH BELOW NORMAL TEMPS. HIGHS MAY REMAIN IN
THE 60S TUESDAY.
POOL OF COOL AIR ALOFT WILL BE SLOW TO EXIT MIDWEEK AND WEDNESDAY
LOOKS LIKE ANOTHER COOL DAY. THE RETURN OF WARMER AIR BEGINS
THURSDAY AND FRIDAY AS RIDGING OVER THE ROCKIES EXPANDS EASTWARD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1200 PM CDT SAT JUN 28 2014
TWO ISSUES AT TAF ISSUANCE. FIRST IS THE MVFR CEILINGS THAT
STRETCH FROM KAXN TO KRWF ON EASTWARD. THE CEILINGS ARE SLOWLY
LIFTING AS MIXING INCREASES DUE TO DEEPENING LOW PRESSURE OVER THE
DAKOTAS. GRADUALLY BROUGHT ALL SITES UP TO VFR DURING THE
AFTERNOON. THE SECOND ISSUE IS THE FINE LINE OF CONVECTION ALONG A
PREFONTAL CONVERGENCE ZONE NEAR KAXN TO KRWF. LATEST HRRR AND 12Z
HOPWRF MEMBERS ARE IN GOOD AGREEMENT ON CONVECTION INCREASING IN A
NORTH-SOUTH LINE DURING THE AFTERNOON AS IT HEADS SLOWLY EAST.
TIMED THE CONVECTION PER THE AFOREMENTIONED SOLUTIONS. THE MOST
ROBUST ACTIVITY AFFECTS THE TWIN CITIES IN THE 22Z-24Z TIME FRAME.
THE CONVECTION WILL BE MOVING ACROSS WEST CENTRAL WI EARLY THIS
EVENING. SOME CLEARING IN THE WAKE OF THE STORMS TONIGHT COUPLED
WITH THE MOIST LOW LEVELS AND DIMINISHING WIND WILL ALLOW MVFR OR
LOWER CEILINGS TO DEVELOP. CONFIDENCE IS HIGHEST ACROSS EASTERN MN
AND WEST CENTRAL WI WHERE AFTERNOON/EVENING SHOWERS AND
THUNDERSTORMS WILL OCCUR...MOISTENING THE BOUNDARY LAYER EVEN
MORE BEFORE SUNSET. PRELIMINARY LOOK AT SUNDAY SUGGESTS MUCH OF THE
CONVECTION MAY BE JUST SOUTH OF KRWF-KMSP-KEAU. WINDS THIS
AFTERNOON SSE 15-20 KNOTS GUSTING 25-30 KNOTS. WINDS SUNDAY SSW
15-20 KNOTS GUSTING 25-30 KNOTS.
KMSP...CEILINGS LIFTING TO VFR EARLY THIS AFTERNOON. SEVERAL WAVES
OF CONVECTION EXPECTED AT THE AIRFIELD IN THE 22Z-24Z TIME PERIOD
WITH GUSTY SW WINDS TO 40 KNOTS AND SMALL HAIL. MVFR CEILINGS ARE
FORECAST FOR LATE TONIGHT AND EARLY SUNDAY WITH VFR THEREAFTER.
/OUTLOOK FOR KMSP/
SUN NITE...VFR. WINDS SW 10KTS.
MON...VFR. WINDS W 10-15KTS.
TUE...VFR WITH MVFR CIGS POSSIBLE. WINDS NW 20KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...DWE
LONG TERM...BORGHOFF
AVIATION...RAH
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
910 PM CDT SUN JUN 29 2014
.UPDATE...
00Z EVENING ANALYSIS INDICATES H5 UPPER RIDGING CONTINUES TO BUILD
INTO THE REGION AND THE SURFACE HIGH IN THE NRN GULF SLOWLY DRIFTS TO
THE NW. 00Z KJAN/KSHV SOUNDINGS INDICATES INCREASING LOW LEVEL
CAPPING INVERSION...WHICH HELD CONVECTIVE ACTIVITY AT A MINIMUM THIS
AFTERNOON. LIGHT SRLY FLOW WILL KEEP FOG POTENTIAL LOW
OVERNIGHT...BUT SOME STRATUS COULD BUILD BACK INTO ALONG AND S OF
I-20 AND MAINLY IN THE SW. DUE TO CURRENT DEWPOINTS RUNNING SLIGHTLY
WARMER AND CAPPING INVERSION...THERE REMAINS POTENTIAL FOR SOME LOW
STRATUS TONIGHT. THIS IS SUPPORTED IN THE HRRR/SREF CEILING PROBS
OVERNIGHT AROUND 12Z MONDAY. LOWS TONIGHT WENT SLIGHTLY WARMER IN THE
W/SW DUE TO DEWPOINTS CURRENTLY RUNNING WARMER THAN LAV GUIDANCE AND
POTENTIAL FOR LOWER STRATUS OVERNIGHT TONIGHT. ONLY ADJUSTED HOURLY
TEMPS/DEWPOINT/SKY GRIDS TO CURRENT TRENDS. REST OF THE FORECAST IS
ON TRACK. /DC/
&&
.AVIATION...VFR CONDITIONS WILL EXIST FOR MUCH OF TONIGHT WITH A
TREND TOWARD SOME PATCHY MVFR VIS CONDITIONS BY 10-11Z.
ADDITIONALLY...HRRR GUIDANCE IS INDICATING SOME PATCHY IFR CEILINGS
MAY DEVELOP BETWEEN 11-13Z FOR LOCATIONS ALONG AND S OF I-20.
CONFIDENCE IS NOT REAL HIGH ON THIS DEVELOPMENT AT THE MOMENT...BUT
SOMETHING TO KEEP AN EYE ON. LOOK FOR ANY RESTRICTED CONDITIONS TO
BREAK BY 14-15Z WITH VFR CONDITIONS PREVAILING ON MONDAY. /CME/
&&
.PREV DISCUSSION... /ISSUED 345 PM CDT SUN JUN 29 2014/
DISSCUSSION...THE UPPER RIDGE WAS BUILDING IN FROM THE SOUTHWEST.
THE UPPER DISTURBANCE MOVING THROUGH THE MID SOUTH HAS FINALLY
SHIFTED EAST...BUT THE TROUGH AXIS EXTENDS SOUTH INTO THE NORTHEAST
ZONES. SHOWERS WERE DEVELOPING ACROSS THE NORTH WITH A THUNDERSTORM
OR TWO IN THE NORTHEAST ZONES. WITH PLENTY OF MOISTURE
AVAILABLE...HEAVY RAIN IS LIKELY. THE RUC CARRIED RAIN INTO THE NIGHT
AND EXTENDED INTO THE CENTRAL ZONES. HOWEVER...THE LOCAL WRF AND THE
REST OF THE MODELS KEPT THE ACTIVITY NORTH. THE GFS CAME IN WITH LOW
POPS FOR THE CWA TONIGHT. BASED ON WHAT`S HAPPENING...DECIDED TO
STICK WITH GUIDANCE. WENT WITH A PRE FIRST PERIOD TO KEEP THE MENTION
OF SHOWERS AND THUNDERSTORMS THROUGH THE EARLY EVENING. EXPECTING
CONVECTION TO END WITH THE LOSS OF THE SUN.
GUIDANCE SEEMED GOOD. NEAR NORMAL TEMPS LOWER TO MID 90S AND LOWER 70S
WILL MAINTAIN THROUGH MID WEEK. HEAT INDEX VALUES MAY APPROACH 100 OR
THE LOWER 100S. MODEL SOUNDINGS SUPPORT GOOD SUBSIDENCE BY MONDAY
AFTERNOON...SO THE AREA SHOULD REMAIN DRY...ALTHOUGH SURFACE MOISTURE
WILL HANG AROUND. DRY CONDITIONS HANG AROUND THROUGH EARLY WEDNESDAY.
THE NEXT UPPER TROUGH AND FRONT DROP INTO THE AREA BY WEDNESDAY
AFTERNOON BRINGING SMALL RAIN CHANCES BACK TO THE AREA.
NO REAL CHANGES TO THE FORECAST. THE AREA WILL GET A SHORT BREAK FROM
THE RAIN...BUT THE HEAT WILL RETURN. /07/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 73 94 73 95 / 0 3 4 7
MERIDIAN 71 94 69 95 / 0 7 4 7
VICKSBURG 73 92 71 94 / 0 3 4 8
HATTIESBURG 73 95 72 96 / 0 4 9 8
NATCHEZ 74 90 72 92 / 0 3 7 6
GREENVILLE 74 93 73 95 / 0 2 4 9
GREENWOOD 73 93 72 95 / 0 3 4 8
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
DC/CME/07
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
949 PM CDT Sun Jun 29 2014
.UPDATE:
Issued at 948 PM CDT Sun Jun 29 2014
Scattered thunderstorms over north central and northwest Missouri
are occurring in an axis of 925-850mb moisture convergence that
shows up well in latest run of the RAP. This forcing will shift
eastward the next few hours as the low level winds veer. Current
motion of the supercell over north central Missouri has it moving
into the the northwestern CWA around midnight. HRRR composite
reflectivity still shows that current activity will move east into
central and northeast Missouri and west central Illinois through
09Z before diminishing. Have maintained likely PoPs during the late
evening and overnight hours in these areas with chance PoPs
elsewhere. Rest of forecast still looks on track.
Britt
&&
.SHORT TERM: (Through Late Tonight)
Issued at 357 PM CDT Sun Jun 29 2014
An area of convection was moving through southeastern MO, clipping
the extreme southern portion of the forecast area this afternoon,
with more scattered activity mainly between COU and STL. This
convection was mainly due to diurnal heating and destabilization and
should dissipate by sunset. More organized convection is expected
to develop this evening and move through the northern and western
portion of our forecast area late this evening and overnight.
Convection is expected to develop across southeastern Nebraska,
northeast Kansas and southwest Iowa late this afternoon and early
this evening ahead of a vort max or MCV moving eastward into
northeast KS, and in an area of low level warm air advection on the
nose of a s-swly low level jet. Some of this convection should move
southeastward into central MO late this evening and into the
overnight hours with additional convection developing or moving into
northeast MO and west central IL during this time period as well.
The atmosphere will be very unstable and there will be adequate
low-mid level wind shear that some of the storms across northeast MO
could be severe with damaging winds being the most likely hazard.
Most of the convection should remain north and west of STL. Low
temperatures tonight should be a little warmer than the previous
night due to slightly stronger surface winds and slightly higher
surface dew points.
GKS
.LONG TERM: (Monday through Next Sunday)
Issued at 357 PM CDT Sun Jun 29 2014
It appears that going forecasts have a fairly good handle on
convective/precip trends heading into the new work week, which
remains the primary short-term forecast concern.
Although the exact evolution of tonight`s activity is still a bit
uncertain, based on model consensus and climatology any convection
that is generated during the overnight hours should be exiting
southeast sections of the CWA early Monday morning. Once this
occurs, there should be a fairly prolonged period of dry weather as
very warm mid-level temps cap any additional development until the
approach of the cold front towards northwest sections of our CWA
late in the day. It certainly appears that the last day of June is
going to be a steamy one over most of the FA, and even taking into
account mixing it appears that dewpoints will hold in the low-mid
70s over most of the region. Don`t believe that the low clouds of
today will be hanging around tomorrow, especially in the afternoon,
so with at least partial sunshine and 850mb temps of 20-22C progged
over the region highs should be topping out in the low-mid 90s.
This combo of temperatures and dewpoints will push the afternoon
heat index to around 105 degrees in the STL metro, so will be going
out with a heat advisory for this area from 17z Monday-01z Tuesday
(Monday afternoon and early evening).
Obviously this AMS will be extremely unstable, and as the
aforementioned cold front and associated shortwave interact with it
during the afternoon a large area of strong to severe convection
will develop from IA and possibly extending into northwest and/or
north central MO. Some of these storms may threaten northwest
sections of the FA by late in the afternoon, but the primary threat
in our CWA will likely be Monday evening. There will certainly be
some severe weather potential in northern sections of our CWA with
this activity due to the extreme instability (even some of the more
conservative output suggests MUCAPES of 3000-4000 j/kg) and 30-50kts
of bulk shear> However, all of the operational models suggest
intensity and coverage of convection should wane as cold front
pushes into southern sections of the CWA later in the night, and
this appears reasonable with primary shortwave energy tracking
almost due east along with weakening frontal convergence and
instability. Again, this trend is already in going forecast and
looks good.
Synoptic scale models are still suggesting several additional
shortwaves will migrate through the region Tuesday-Tuesday night as
upper trof deepens from the Great Lakes into the Mississippi
Valley. These dynamics should interact with moisture near and
north of slowing cold front to maintain some shower and thunderstorm
threat. Best chances should be over the southern half of the CWA
on Tuesday night, but given the baroclinicity and potential
iscentropic lift have continued some very low slight chance PoPs as
far north as UIN. The threat of precip with the last shortwave
should wind down on Wednesday.
Latest medium range guidance still suggests some atypically cool and
low humidity air will blanket the area heading into the 4th of July
holiday. However, temperatures and humidity levels should begin to
rebound to more normal summertime levels during the weekend as trof
works east and ridge over the Rockies rebounds into the central
CONUS. A threat of showers and thunderstorms will return during
the latter half of the weekend as a shortwave on east side of
ridge clips the area.
Truett
&&
.AVIATION: (For the 00z TAFs through 00z Monday Evening)
Issued at 621 PM CDT Sun Jun 29 2014
Sly winds will continue thru tonight. A TSRA complex is expected
to develop across ern KS and move ewd this evening. Latest
guidance suggests this complex will impact COU with another
complex potentially impacting UIN late tonight. Have kept VCTS
mention going for now and will update as timing becomes more
confident. Uncertainty remains how far E this complex will
propagate before dissipating. Guidance suggests it will dissipate
as it arrives in the SUS/CPS area, or track just N of the
terminals. Due to lower probability, have kept TAF dry for now.
Otherwise, expect MVFR cigs to develop around sunrise Mon morning
once again with cigs breaking up during the late morning hours.
Gusty sly to swly winds are expected into the early evening hours
Monday.
Specifics for KSTL: Sly winds will continue thru tonight. A TSRA
complex is expected to develop across ern KS and move ewd this
evening. Uncertainty remains how far E this complex will propagate
before dissipating. Guidance suggests it will dissipate as it arrives
in the area, or track just N of the terminal. Due to lower
probability, have kept TAF dry for now. Otherwise, expect MVFR
cigs to develop around sunrise Mon morning once again with cigs
breaking up during the late morning hours. Gusty sly to swly winds
are expected into the early evening hours Monday.
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...HEAT ADVISORY from Noon to 8 PM CDT Monday FOR St. Charles MO-
St. Louis City MO-St. Louis MO.
IL...HEAT ADVISORY from Noon to 8 PM CDT Monday FOR Madison IL-St.
Clair IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
943 PM CDT Sun Jun 29 2014
.UPDATE...
Issued at 937 PM CDT SUN JUN 29 2014
00Z/7pm CDT upper air observation at KSGF shows some warming in
the 800-700mb with ongoing warm air advection in that layer.
Progged soundings for the same time (00z), while overdoing the
cap/warming, have latched onto the idea of fairly poor lapse rates
in that layer. In the near term, looking for continued quiet
weather.
Later tonight....New 00z NAM (and the 18z) is just doing a terrible job
in the near term with convection. HRRR and ARW (among some others)
seem to have a good general handle with ongoing convection over NE
Kansas/NW Missouri. Could see convection develop southeast with
convective outflow interacting with the nocturnal low level jet
overnight. Best chances for precip would be over the northern
cwfa, but overall have cut back on pops and severe weather chances
tonight (still limited). Will continue to watch trends unfold and
make adjustments as needed.
&&
.SHORT TERM...(This Evening through Monday)
Issued at 249 PM CDT SUN JUN 29 2014
The active weather pattern will continue through Monday...and
beyond. As we go through early this evening, we are expecting
pop-up type convection over the eastern Ozarks to slowly wane.
Meanwhile, confidence is beginning to increase that we may have to
deal with another line of storms from later this evening into the
overnight period. We will be closely watching for convective
initiation across northeastern Kansas/northern Missouri this
afternoon. Cold pools from what will initially be cellular
convection should quickly conglomerate given very high low level
theta-e differentials. Once conglomeration occurs and a low level
jet strengthens this evening, any developing MCS should take a
hard turn to the south-southeast and become forward-propagating
in nature. It will certainly have damaging wind potential given
extreme instability and high theta-e differentials (especially
north of I-44).
Timing remains a question as it will be highly dependent on
if/when initiation occurs across the I-70 corridor. It could
come into west-central Missouri as early as 7 to 8 PM...but may
also hold off until late evening. Regardless, we will be ramping
up PoPs tonight and hitting the wind potential in the Hazardous
Weather Outlook products. We will also have to watch for
regenerative growth later tonight if the convective outflow stalls
and interacts with the low level jet.
It should be noted that there are also multiple convection-
allowing models that do not generate an MCS at all to our north.
If the MCS does not pan out, we would be left with isolated to
widely scattered convective potential as a low level jet veers
over the region later tonight. The bottom line here...we will be
keeping our eyes peeled on the I-70 corridor into this
evening...making forecast adjustments if necessary.
Any leftover activity should quickly diminish Monday morning with
the majority of the day looking dry, hot, and humid. Highs will
have no problem warming into the lower 90s with heat indices in
the 98 to 104 degree range. It will also be a windy day with brisk
and gusty south to southwest surface winds. By late in the
afternoon, we are expecting another MCS to develop up towards I-70
along an advancing cold front. It is possible that this activity
approaches the Truman and Lake of the Ozarks region by late
afternoon. Once again, this activity will have wind damage
potential.
.LONG TERM...(Monday Night through Sunday)
Issued at 249 PM CDT SUN JUN 29 2014
That cold front will then seep south into the area Monday night
and Tuesday continuing the threat for showers and thunderstorms.
That front will then get nudge into northern Arkansas from Tuesday
night into Wednesday morning. More showers and thunderstorms are
probable, especially across extreme southeastern Kansas and
southern Missouri during this time period. A threat for strong to
severe storms will remain...with perhaps an increasing threat for
flooding due to a cumulative effect from multiple rounds of
thunderstorms. We considered a Flash Flood Watch, but would like
to get a better feel for the track of MCSs before pulling the
trigger.
The threat for storms should finally push south of the Missouri
Ozarks by Wednesday night with dry and cooler weather currently
anticipated from Thursday through Saturday. High temperatures will
be pleasant with highs in the upper 70s to lower 80s and lows in
the lower 60s.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday Evening)
Issued at 720 PM CDT SUN JUN 29 2014
For the KSGF/KJLN/KBBG tafs: VFR conditions will occur in the near
term. An area of thunderstorms over ne KS/nw MO and any further
development will be watched over the next few hours. Some guidance
has this convection eventually developing southeast in the form of
a weakening convective complex and outflow boundary. Have a prob30
group for this possibility for now. The latest upper air
observation and progged soundings have shown some increased
capping/warming in the 800-700mb level and this could limit
overall potential if the line of storms doesn`t develop. Kept a
marginal mention of low level wind shear in all tafs with modest
speed but fairly good directional shear. Should see some
moderately gusty winds late in the taf period with daytime mixing
with 20-25 kts gusts possible.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
UPDATE...DSA
SHORT TERM...Schaumann
LONG TERM...Schaumann
AVIATION...DSA
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
342 PM CDT Sat Jun 28 2014
.SHORT TERM: (Through Late Tonight)
Issued at 341 PM CDT Sat Jun 28 2014
Scattered showers and storms have developed this afternoon, mainly
across central and northeast MO into west central IL, due to diurnal
heating and destabilization. Although most of this current activity
will dissipate by sunset, a more organized band of showers and
storms is expected to translate eastward through our forecast area
the evening into the overnight hours. This convection is ahead of a
shortwave trough currently extending across eastern portions of
Nebraska and Kansas. The HRRR model moves this band of convection
eastward into central MO just after 7 pm, then into the St Louis
metro area by late evening. There may be some strong wind gusts
with these storms across northeast and central MO. The convection
may gradually weaken late this evening and overnight as it shifts
eastward through the St Louis metro area. Low temperatures will be
similar to last night, generally in the lower 70s.
GKS
.LONG TERM: (Sunday through Next Saturday)
Issued at 341 PM CDT Sat Jun 28 2014
Overall, it appears that the unsettled weather trend will continue
across the region heading into the start of the new week. Trying to
pin down these periodic storm chances remain the primary forecast
concern.
For Sunday, forecast will reflect the thinking that tonight`s
convection should be exiting southeast sections of the CWA on Sunday
morning; however, if tonight`s complex is quicker than expected,
then these morning PoPs may be too high. Once this activity exits,
then the question is whether there will be any redevelopment as AMS
destabilizes during the afternoon. Short range guidance based off of
12z UA data does suggest several very weak ripples in the flow that
will impact the area during the afternoon during max heating,
but they are also indicating warming mid level temps along and west
of the Mississippi River that may tend to cap any surface based
redevelopment. GFS and GEM are a bit more bullish on the increase
of 7h temps over central MO, so have left forecast dry in this area
with slight chance/low chance PoPs elsewhere.
Intense onvection is expected to blossom over the mid-Missouri
Valley Sunday afternoon in the very unstable airmass near the
surface boundary and ahead of the next shortwave, with this activity
quickly growing upscale into a convective complex that will then
work into the mid-Mississippi Valley during the overnight hours.
While there is still uncertainly on the exact location of storm
genesis, all storm propagation vectors from the various 12z
solutions have a fairly pronounced southerly component which
suggests complex try to build into our CWA with time. Based on
this, I`ve tried to be fairly generous with the southward expansion
of PoPs and have taken mention of thunder to the I44 corridor in
MO/I70 corridor in IL by 12z Monday.
Remnants of Sunday nights convection will exit Monday morning, and
then there should be a bit of a lull before the third round of
convection sweeps across the region (primarily on Monday night) as
main cold front and associated shortwave move into the region and
interact with the very unstable airmass. Depending upon the amount
of cloud cover, Monday should certainly be one of the warmest day so
far this summer with 850MB temps of 20-22C and gusty southwest
winds, and have maintained going highs in the low-mid 90s over all
but our far NW counties.
Medium range output continues to suggest below average temperatures,
and unusually low summertime humidities, for the first several days
of July. Guidance remains in good agreement that axis of atypically
deep mid level trof will work into the Great Lakes region, bringing
relatively cool and dry air into the mid-Mississippi Valley.
Several shortwaves rotating through the trof will track across the
region at the same time, which will likely mean a continuation of
some shower and thunderstorm threat in the Tuesday-Wednesday time
frame, mainly over southern sections of the CWA where dynamics will
have the best chance to interact with the lower level
baroclinicity.
Right now it looks like more typical temps/humidity levels will be
returning by the Fourth of July weekend as upper trof works east and
ridging expands from the Rockies into the central CONUS. Rain
chances look to be quite low in the Thursday-Saturday time
frame.
Truett
&&
.AVIATION: (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1251 PM CDT Sat Jun 28 2014
Scattered showers and a few storms were developing early this
afternoon from the COU area ne through UIN area. Should also get
at least widely scattered showers and storms to develop later this
afternoon in the St Louis metro area. A second round of
showers/storms is expected this evening into the overnight hours
as an upper level disturbance moves eastward through the area.
Diurnal cumulus clouds will develop again Sunday morning leading
to a possible brief period of MVFR ceilings. Sly surface wind will
become more swly by Sunday morning.
Specifics for KSTL: Widely scattered to scattered showers/storms
will develop this afternoon and continue until early evening. A
second round of showers/storms is expected late this evening into
the overnight hours. Diurnal cumulus clouds will develop again
Sunday morning leading to a possible brief period of MVFR
ceilings. Sly surface wind will become more swly by Sunday
morning.
GKS
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
102 PM CDT Sat Jun 28 2014
.SHORT TERM: (Through Late This Afternoon)
Issued at 405 AM CDT Sat Jun 28 2014
Convective trends are once again the primary forecast problem for
today. Still plenty of moisture, and forecast soundings indicate a
little more instability than yesterday. There is a well developed
MCV over Oklahoma which will move northeast and produce another
round of precipitation over western Missouri from late morning into
the afternoon, and there is another subtle shortwave currently over
western Missouri which the RUC and HRRR seem to be keying on to
produce widely scattered convection over central and northeast
Missouri early this morning. Have a pretty high confidence it will
rain somewhere in the CWFA, sometime today due to these features,
tho confidence is low on exact timing and coverage. Generally
speaking tho we should see a general increase in coverage due to
diurnal heating in the afternoon. MOS temperatures in the mid to
upper 80s looked reasonable for highs today with 850mb temps in the
16-18C range, tho any convection will have a large impact on what
highs actually turn out to be.
Carney
.LONG TERM: (Tonight through Friday)
Issued at 405 AM CDT Sat Jun 28 2014
A strong storm system over the Plains currently will track
east-northeast into IA and the Upper MS Valley tonight. This will
tail a vorticity lobe into our region, and this should be plenty to
work convection in and keep it going thru much of the night. This
convection will probably come in two waves...the first working in
during the evening having already formed further west earlier and
then accelerating east and weakening. Enough shear and instability
with what should be a mature enough development to warrant a risk
for damaging winds in NE and Central MO. Another, more sustained,
but likely not severe, wave of convection to then move thru
overnight and should keep going--this being supported better by the
upper level shortwave. Rain from this wave should then exit on
Sunday morning with some redevelopment in the afternoon possible.
A MCS is expected to form to our northwest over the Mid-MO valley
Sunday night and then track eastward. The main effect will largely
miss our region, but this should lay out a boundary for additional
development Monday with anticipated destabilization on its south
side. Once the synoptic cold front catches up with this Monday
night and into Tuesday, should see higher PoPs for more widespread
rain.
With what should be a more northwesterly mid-level flow heading into
the middle of next week, this front is expected to push well south,
allowing for a series of cool high pressures to invade and settle in
for the end of the week. A dry forecast is therefore in order for
most areas to close out the 7-day forecast.
Temps to remain at or above normal until about the middle of next
week, peaking on Monday with widespread 90s expected. Temps Monday
a bit questionable in the north with interference from MCS boundary
and enhanced rain chances but I-70 and south, it looks hot.
Afternoon heat index values may top out at close to 105 for STL
metro and this will need to be watched for need of an Advisory. A
couple of bonus nice days Wednesday and Thursday with maxes in the
lo-mid 80s. Despite east-southeast flow on the 4th of July, rising
heights to 590dm at h500 will warrant higher temps that day, but
still looks to be mid-upper 80s for now. A more typical summertime
ridging pattern aloft looks to be in store for the rest of the
holiday weekend and into the following week with what could be a
prolonged period of hot weather. Summer is here.
TES
&&
.AVIATION: (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1251 PM CDT Sat Jun 28 2014
Scattered showers and a few storms were developing early this
afternoon from the COU area ne through UIN area. Should also get
at least widely scattered showers and storms to develop later this
afternoon in the St Louis metro area. A second round of
showers/storms is expected this evening into the overnight hours
as an upper level disturbance moves eastward through the area.
Diurnal cumulus clouds will develop again Sunday morning leading
to a possible brief period of MVFR ceilings. Sly surface wind will
become more swly by Sunday morning.
Specifics for KSTL: Widely scattered to scattered showers/storms
will develop this afternoon and continue until early evening. A
second round of showers/storms is expected late this evening into
the overnight hours. Diurnal cumulus clouds will develop again
Sunday morning leading to a possible brief period of MVFR
ceilings. Sly surface wind will become more swly by Sunday
morning.
GKS
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
702 AM CDT Sat Jun 28 2014
.SHORT TERM: (Through Late This Afternoon)
Issued at 405 AM CDT Sat Jun 28 2014
Convective trends are once again the primary forecast problem for
today. Still plenty of moisture, and forecast soundings indicate a
little more instability than yesterday. There is a well developed
MCV over Oklahoma which will move northeast and produce another
round of precipitation over western Missouri from late morning into
the afternoon, and there is another subtle shortwave currently over
western Missouri which the RUC and HRRR seem to be keying on to
produce widely scattered convection over central and northeast
Missouri early this morning. Have a pretty high confidence it will
rain somewhere in the CWFA, sometime today due to these features,
tho confidence is low on exact timing and coverage. Generally
speaking tho we should see a general increase in coverage due to
diurnal heating in the afternoon. MOS temperatures in the mid to
upper 80s looked reasonable for highs today with 850mb temps in the
16-18C range, tho any convection will have a large impact on what
highs actually turn out to be.
Carney
.LONG TERM: (Tonight through Friday)
Issued at 405 AM CDT Sat Jun 28 2014
A strong storm system over the Plains currently will track
east-northeast into IA and the Upper MS Valley tonight. This will
tail a vorticity lobe into our region, and this should be plenty to
work convection in and keep it going thru much of the night. This
convection will probably come in two waves...the first working in
during the evening having already formed further west earlier and
then accelerating east and weakening. Enough shear and instability
with what should be a mature enough development to warrant a risk
for damaging winds in NE and Central MO. Another, more sustained,
but likely not severe, wave of convection to then move thru
overnight and should keep going--this being supported better by the
upper level shortwave. Rain from this wave should then exit on
Sunday morning with some redevelopment in the afternoon possible.
A MCS is expected to form to our northwest over the Mid-MO valley
Sunday night and then track eastward. The main effect will largely
miss our region, but this should lay out a boundary for additional
development Monday with anticipated destabilization on its south
side. Once the synoptic cold front catches up with this Monday
night and into Tuesday, should see higher PoPs for more widespread
rain.
With what should be a more northwesterly mid-level flow heading into
the middle of next week, this front is expected to push well south,
allowing for a series of cool high pressures to invade and settle in
for the end of the week. A dry forecast is therefore in order for
most areas to close out the 7-day forecast.
Temps to remain at or above normal until about the middle of next
week, peaking on Monday with widespread 90s expected. Temps Monday
a bit questionable in the north with interference from MCS boundary
and enhanced rain chances but I-70 and south, it looks hot.
Afternoon heat index values may top out at close to 105 for STL
metro and this will need to be watched for need of an Advisory. A
couple of bonus nice days Wednesday and Thursday with maxes in the
lo-mid 80s. Despite east-southeast flow on the 4th of July, rising
heights to 590dm at h500 will warrant higher temps that day, but
still looks to be mid-upper 80s for now. A more typical summertime
ridging pattern aloft looks to be in store for the rest of the
holiday weekend and into the following week with what could be a
prolonged period of hot weather. Summer is here.
TES
&&
.AVIATION: (For the 12z TAFs through 12z Sunday Morning)
Issued at 644 AM CDT Sat Jun 28 2014
Thunderstorms remain the primary concern for today. Expecting
areas of MVFR and patchy IFR CIGS (primarily over Illinois) to lift
through the morning. VFR flight conditions should prevail across
the area by late morning or early afternoon. Then, expect widely
scattered thunderstorms again this afternoon due to daytime
heating. Currently, it looks like the best chance for storms will
be over central Missouri where an outflow boundary from storms
this morning over Kansas will combine with support from an upper
level disturbance. Storms should weaken and dissipate somewhat
after sunset, but there will be another chance of storms later
Saturday night primarily over eastern Missouri and southwest
Illinois as another disturbance moves across the area.
Specifics for KSTL:
Thunderstorms remain the primary concern for today. Any remaining
threat of MVFR CIGS should be done by 14-15Z this morning.
Attention then turns to thunderstorm chances, which will increase
through the afternoon. Expect that widely scattered storms will
decrease in coverage after peak heating as we lose instability.
There will be another chance of thunderstorms overnight as an
upper level disturbance moves across the area. VFR flight
conditions are expected outside of storms.
Carney
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
405 AM CDT Sat Jun 28 2014
.SHORT TERM: (Through Late This Afternoon)
Issued at 405 AM CDT Sat Jun 28 2014
Convective trends are once again the primary forecast problem for
today. Still plenty of moisture, and forecast soundings indicate a
little more instability than yesterday. There is a well developed
MCV over Oklahoma which will move northeast and produce another
round of precipitation over western Missouri from late morning into
the afternoon, and there is another subtle shortwave currently over
western Missouri which the RUC and HRRR seem to be keying on to
produce widely scattered convection over central and northeast
Missouri early this morning. Have a pretty high confidence it will
rain somewhere in the CWFA, sometime today due to these features,
tho confidence is low on exact timing and coverage. Generally
speaking tho we should see a general increase in coverage due to
diurnal heating in the afternoon. MOS temperatures in the mid to
upper 80s looked reasonable for highs today with 850mb temps in the
16-18C range, tho any convection will have a large impact on what
highs actually turn out to be.
Carney
.LONG TERM: (Tonight through Friday)
Issued at 405 AM CDT Sat Jun 28 2014
A strong storm system over the Plains currently will track
east-northeast into IA and the Upper MS Valley tonight. This will
tail a vorticity lobe into our region, and this should be plenty to
work convection in and keep it going thru much of the night. This
convection will probably come in two waves...the first working in
during the evening having already formed further west earlier and
then accelerating east and weakening. Enough shear and instability
with what should be a mature enough development to warrant a risk
for damaging winds in NE and Central MO. Another, more sustained,
but likely not severe, wave of convection to then move thru
overnight and should keep going--this being supported better by the
upper level shortwave. Rain from this wave should then exit on
Sunday morning with some redevelopment in the afternoon possible.
A MCS is expected to form to our northwest over the Mid-MO valley
Sunday night and then track eastward. The main effect will largely
miss our region, but this should lay out a boundary for additional
development Monday with anticipated destabilization on its south
side. Once the synoptic cold front catches up with this Monday
night and into Tuesday, should see higher PoPs for more widespread
rain.
With what should be a more northwesterly mid-level flow heading into
the middle of next week, this front is expected to push well south,
allowing for a series of cool high pressures to invade and settle in
for the end of the week. A dry forecast is therefore in order for
most areas to close out the 7-day forecast.
Temps to remain at or above normal until about the middle of next
week, peaking on Monday with widespread 90s expected. Temps Monday
a bit questionable in the north with interference from MCS boundary
and enhanced rain chances but I-70 and south, it looks hot.
Afternoon heat index values may top out at close to 105 for STL
metro and this will need to be watched for need of an Advisory. A
couple of bonus nice days Wednesday and Thursday with maxes in the
lo-mid 80s. Despite east-southeast flow on the 4th of July, rising
heights to 590dm at h500 will warrant higher temps that day, but
still looks to be mid-upper 80s for now. A more typical summertime
ridging pattern aloft looks to be in store for the rest of the
holiday weekend and into the following week with what could be a
prolonged period of hot weather. Summer is here.
TES
&&
.AVIATION: (For the 06z TAFs through 06z Saturday Night)
Issued at 1117 PM CDT Fri Jun 27 2014
There is still some low chance for thunderstorms to redevelop
toward sunrise, but this chance is not high enough to include in
any of the TAFs at this time. Have maintained broken ceilings
between 1200-1500ft AGL developing after 09Z as there is some
indication of these ceilings currently over the plains, and
latest model guidance still points to these conditions developing
overnight and lasting through mid morning. Also expect scattered
thunderstorms to redevelop by midday and continue until just
before sunset. Additional thunderstorms are expected tomorrow
evening, though did not include with this TAF issuance because do
not have enough confidence on timing. Brief MVFR or possibly IFR
conditions can be expected with the heavier cores.
Specifics for KSTL: Have kept 1200 foot ceilings between 10-15Z
for now as lower atmosphere is very moist from recent rainfall and latest
model guidance still points to these conditions developing overnight
and lasting through mid morning. Also expect scattered
thunderstorms to redevelop by midday and continue until just
before sunset. Additional thunderstorms are expected tomorrow
evening, though did not include with this TAF issuance because do
not have enough confidence on timing.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1057 PM CDT SUN JUN 29 2014
.SYNOPSIS...
ISSUED AT 251 PM CDT SUN JUN 29 2014
WEATHER CONDITIONS WILL CLOSELY MONITORED FOR SEVERE
STORM DEVELOPMENT OVERNIGHT. A COLD FRONT WILL MOVE THROUGH LATE
TONIGHT AND MONDAY MORNING STABILIZING THE ATMOSPHERE. A
REINFORCING COLD FRONT ARRIVES TUESDAY. COOL WEATHER CONTINUES
THROUGH WEDNESDAY FOLLOWED BY A WARMING TREND THURSDAY THROUGH
SUNDAY WITH NEAR OR SLIGHTLY ABOVE NORMAL TEMPERATURES AND
GENERALLY ISOLATED RAIN CHANCES.
&&
.UPDATE...
ISSUED AT 1056 PM CDT SUN JUN 29 2014
UPDATED FORECAST TO ACCOUNT FOR ECHOES MOVING INTO SOUTHWEST
NEBRASKA FROM NORTHEAST COLORADO. LOW LEVEL JET TO KICK UP AGAIN
TONIGHT AND EXPAND THUNDERSTORMS FROM NORTHERN KANSAS NORTH INTO
NORTH CENTRAL NEBRASKA SIMILAR TO LAST NIGHT. HAVE BEEN A BIT
LIBERAL WITH NORTHWARD PROGRESSION.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 251 PM CDT SUN JUN 29 2014
TONIGHT AND TOMORROW. CONVECTION CHANCES TO HEADLINE
THE SHORT TERM DISCUSSION. KEEPING SLIGHT CHANCE TO LOW END CHANCE
OF POPS IN THE FORECAST FOR LOCATIONS GENERALLY EAST OF HIGHWAY 83
THIS AFTERNOON AND EVENING. UNDER MOSTLY CLEAR SKIES THE ATMOSPHERE
HAS UNDERGONE STRONG DESTABILIZATION...WITH THE OPERATIONAL RAP AND
LATEST LAPS DATA GENERATING UPWARDS OF 3000 J/KG OF MUCAPE ACROSS
SOUTHEASTERN PORTIONS OF THE FORECAST AREA. WITH OPTIMAL DEEP SHEAR
IN PLACE...STORMS...SOME OF WHICH MAY BE SEVERE WITH HAIL AND
DAMAGING WIND BEING THE PRIMARY THREATS...ARE ANTICIPATED TO FORM.
A SIGNIFICANT -10 TO -30C CONTRIBUTION TO THE CAPE /CLOSING ON A
1000 J/KG/ WOULD SUPPORT SOME LARGE HAIL. THE LATEST NEAR TERM
CONVECTION ALLOWING MODELS GENERATES THE PROJECTED ACTIVITY WELL TO
THE EAST OF THE CWA...BUT RECENT SATELLITE OBS INDICATE OTHERWISE
WITH THE FORMATION OF A AGITATED CU FIELD ACROSS CUSTER COUNTY.
WILL CONTINUE TO MONITOR THE CONVECTIVE TRENDS. WEST OF THIS
AREA...INSTABILITY AND AVAILABLE CAPE DECREASES RAPIDLY...ONLY
ISOLATED GENERAL STORMS WOULD BE POSSIBLE.
FOR THE OVERNIGHT...INCREASINGLY RICH THETA-E BUILDS BACK TO THE
NORTHWEST WITH THE STRENGTHENING OF A LLJ. THE THREAT OF STORMS
WILL REMAIN THROUGH THE OVERNIGHT FOR LOCATIONS MAINLY EAST OF
HIGHWAY 83. OVERNIGHT LOWS WILL RANGE FROM THE 50S ACROSS THE
NORTHWEST...TO MID 60S ACROSS THE EAST.
SLIGHTLY COOLER FOR MONDAY WITH A FRONTAL PASSAGE EARLY. HIGHS IN
THE 70S TO LOWER 80S SHOULD PREVAIL. LINGERING POST FRONTAL STORMS
ARE POSSIBLE EARLY MONDAY ACROSS NORTH CENTRAL NEBRASKA...BUT BY
AFTERNOON THIS ACTIVITY SHOULD BE OFF TO THE EAST.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 251 PM CDT SUN JUN 29 2014
MONDAY NIGHT THROUGH WEDNESDAY...A REINFORCING CANADIAN COLD FRONT
WILL MOVE THROUGH TUESDAY. THE PRECEDING PACIFIC COLD FRONT SUPPORTS
LOWS IN THE 50S TUESDAY MORNING. LOWS WEDNESDAY MORNING ARE ABOUT 5F
COLDER FOR LOWS IN THE LOWER 50S. THERE IS POTENTIAL FOR COOLER LOWS
WEDNESDAY MORNING BUT THE MODELS SHOW 850MB-700MB CLOUDS WRAPPING
SOUTH AROUND A DEPARTING UPPER LEVEL LOW ACROSS ONTARIO.
RAIN CHANCES CONTINUE IN PLACE TUESDAY WITH COLD AIR MOVING IN
ALOFT. H700MB TEMPERATURES FALL TO 6C TO 10C AND HIGHS RISE TO ONLY
70 NORTH. NORTHWEST WINDS INCREASE TO 20 TO 30 MPH TUESDAY WITH
HIGH PRESSURE BUILDING SOUTH ALSO.
THE COLD AIR ALOFT MOVES OFF EAST WEDNESDAY FOR HIGHS 75 TO 80 WITH
NEARLY FULL SUN AND LIGHT WINDS...A COMPLETE REVERSE OF TUESDAYS
WIND...CLOUDS...SHOWERS AND COOLER TEMPERATURES.
WEDNESDAY NIGHT THROUGH SUNDAY...THE MODELS ARE IN VERY GOOD
AGREEMENT PRODUCING 20 TO 25 MPH SLY RETURN FLOW THURSDAY AND
FRIDAY. THE WARMING TREND IS SLOWER GIVEN THE STRONGER PUSH OF
CANADIAN AIR TUESDAY FOR HIGHS IN THE 80S TO AROUND 90 THURSDAY
THROUGH SUNDAY. REGARDLESS...INSTABILITY INCREASES IN THE
ECM...GFS AND GEM MODELS THURSDAY THROUGH SATURDAY. IF WINDS ALOFT
CAN REMAIN STRONG AS SHOWN THE GEM AND GFS SOLNS THEN ISOLATED
THUNDERSTORMS COULD DEVELOP IN A NORTHWEST FLOW REGIME THURSDAY
AND BEYOND. THE ECM BUILDS THE UPPER LEVEL RIDGE STRONGLY
PRODUCING WEAK WINDS ALOFT. THE FORECAST FOLLOWS THE GFS AND
INCLUDES ISOLATED POPS WHICH FITS THE CLASSIC JULY NORTHWEST FLOW
CLIMATOLOGY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 655 PM CDT SUN JUN 29 2014
ISOLATED THUNDERSTORMS WILL CONTINUE OVER EASTERN NEBRASKA THROUGH
THE EVENING. THERE IS THE POSSIBILITY OF THUNDERSTORMS OVER
WESTERN NEBRASKA TONIGHT BUT THE PROBABILITY THAT A THUNDERSTORM
WILL OCCUR AT KVTN OR KLBF IS VERY LOW. MOSTLY CLEAR SKIES ARE
EXPECTED WITH LIGHT AND VARIABLE WINDS.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...POWER
SYNOPSIS...CDC
SHORT TERM...JACOBS
LONG TERM...CDC
AVIATION...POWER
AREA FORECAST DISCUSSION
NWS HASTINGS NE
952 PM CDT SUN JUN 29 2014
.UPDATE...
ISSUED AT 928 PM CDT SUN JUN 29 2014
INCREASED POPS ACROSS FAR NORTHERN KANSAS AND MUCH OF SOUTH
CENTRAL NEBRASKA...ESPECIALLY IN THE TRI CITIES AREA. FORECAST
MODELS CONTINUE TO INDICATE A WELL PLACED LOW LEVEL JET WITH
CONVERGENCE ALONG THE NOSE OF THIS JET CENTERED OVER OUR FORECAST
AREA AFTER MIDNIGHT. THE HRRR IS THE FURTHEREST SOUTH WITH THE
CONVECTION FOCUSING THE HEAVIEST CONVECTION OVER NORTH CENTRAL
KANSAS AND THE FAR SOUTHERN TIER OF NEBRASKA COUNTIES AFTER
MIDNIGHT. THE NAM...RAP...AND SREF FOCUS THE CONVECTION A LITTLE
FURTHER NORTH CENTERING THE HIGHEST POPS OVER THE TRI CITIES
BETWEEN 3 AM AND 7 AM. WILL FOLLOW THE CONSENSUS GUIDANCE WITH THE
HIGHEST POPS ACROSS SOUTH CENTRAL NEBRASKA. THUNDERSTORMS SHOULD
BEGIN TO FORM ANYTIME AFTER 10 PM ACROSS SOUTHWEST NEBRASKA NEAR
THE KANSAS STATE LINE AND THEN TRACK EAST POSSIBLY BUILDING SOUTH
INTO NORTHERN KANSAS. SOUNDINGS INDICATE SIGNIFICANT ELEVATED
INSTABILITY WITH OVER 3000 J/KG OF CAPE FROM AN ELEVATED PARCEL.
THE COMBINATION OF HIGH INSTABILITY AND DEEP LAYER WIND SHEAR TO
NEAR 50 KTS WILL CERTAINLY SET THE STAGE FOR THE POSSIBILITY OF A
LATE NIGHT SEVERE WEATHER EVENT. WOULD NOT BE SURPRISED TO SEE
SOME GOLF BALL SIZED OR EVEN LARGER HAIL REPORTS DURING THE
MIDDLE OF THE OVERNIGHT PERIOD.
UPDATE ISSUED AT 631 PM CDT SUN JUN 29 2014
DESPITE THE HIGH INSTABILITY AND STRONG VERTICAL WIND SHEAR...IT
APPEARS THAT THE LACK OF GOOD FORCING HAS BEEN WINNING OUT THIS
EVENING AND THUS WE HAVE SEEN NO CONVECTIVE DEVELOPMENT ACROSS OUR
AREA. THE ONLY THUNDERSTORMS HAVE BEEN EAST OF OUR FORECAST AREA
WHERE THE FORCING IS BETTER. WE ARE COLLABORATING WITH THE SPC ON
TRIMMING SOME OF THE WESTERN COUNTIES FROM OUR TORNADO WATCH. IT
SEEMS LIKELY AT THIS POINT IN TIME THAT MOST OF OUR TORNADO WATCH
WILL BE CANCELED EARLY UNLESS WE START TO SEE SOMETHING DEVELOP
SOON.
WE WILL SEE BETTER FORCING BY LATE EVENING ASSOCIATED WITH THE
INCREASING LOW LEVEL JET WHICH WILL NOSE INTO OUR FORECAST AREA IN
NEAR TEXT BOOK FASHION FOR AN INCREASING THREAT OF ELEVATED
STRONG TO SEVERE THUNDERSTORMS PRIMARILY AFTER 10 PM. WOULD NOT BE
SURPRISED IF A SEVERE THUNDERSTORM WATCH ENDS UP BEING NEEDED
AS WE HEAD TOWARDS MIDNIGHT OR INTO THE PRE DAWN HOURS OF EARLY
MONDAY MORNING.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 332 PM CDT SUN JUN 29 2014
MAIN FORECAST CONCERN WILL BE THUNDERSTORMS THROUGH MONDAY MORNING.
CLOUDS FROM THE MORNING CONVECTION HAVE MAINLY CLEARED OUT OF THE
FORECAST AREA DURING THE EARLY AFTERNOON. A FEW CUMULUS HAVE
STARTED TO DEVELOP BUT NONE OF THEM HAVE MUCH VERTICAL EXTENT
AN UPPER LEVEL WAVE WILL BE MOVING THROUGH THE FORECAST AREA THIS
AFTERNOON AND INTO THE EVENING HOURS. THUNDERSTORMS ARE EXPECTED TO
DEVELOP THIS AFTERNOON IN THE VICINITY OF THE UPPER LEVEL WAVE.
THERE IS OVER 4000 J/KG MU CAPE THIS AFTERNOON AND WITH THE SUNSHINE
THE ATMOSPHERE IS DESTABILIZING AND THUNDERSTORMS ARE EXPECTED TO
DEVELOP THIS AFTERNOON. EXPECT THAT MOST OF THE THUNDERSTORMS SHOULD
MOVE OFF TO THE EAST FAIRLY QUICKLY...MOVING OUT OF THE AREA DURING
THE EVENING. THIS AFTERNOON AND EVENING EXPECT THERE COULD BE HAIL
AND WINDS THE PRIMARY THREAT...BUT AN ISOLATED TORNADO IS NOT OUT OF
THE QUESTION.
LATER TONIGHT ANOTHER UPPER LEVEL WAVE WILL MOVE INTO THE AREA AND
BRING ANOTHER CHANCE FOR SOME THUNDERSTORMS LATER TONIGHT. MODELS
HAVE A FEW DIFFERENCES IN WHERE THE THUNDERSTORMS WILL BE WITH THE
SECOND ROUND OF STORMS. MOST OF THE MODELS TRY TO KEEP IT FURTHER TO
THE NORTH...BUT THE 4KM WRF...HRRR AND EVEN THE NAM KEEP IT A LITTLE
FURTHER SOUTH. WITH THAT IN MIND HAVE KEPT SOME LOWER POPS IN THE
SOUTH WITH HIGHER POPS IN THE NORTH. THIS COULD BRING SOME WIND AND
HEAVIER RAINS WHICH WOULD CAUSE SOME LOCALIZED FLOODING.
THE THUNDERSTORMS SHOULD LAST INTO MONDAY MORNING AGAIN BEFORE
MOVING OFF TO THE EAST. TEMPERATURES SHOULD BE A LITTLE COOLER
DURING THE DAY MONDAY.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 332 PM CDT SUN JUN 29 2014
THE BIGGEST ISSUE WILL BE PERIODIC THUNDERSTORM CHANCES FOR PARTS OF
THE CWA FOR THE BEGINNING AND LATTER PERIODS OF THE LONG TERM.
UPPER LEVEL FLOW WILL BE IN THE PROCESS OF AMPLIFYING...AS A RIDGE
DEVELOPS TO THE WEST AND A SHORTWAVE TROUGH MOVING
THROUGH/APPROACHING THE NORTH/CENTRAL PLAINS THAT WILL EVENTUALLY
SET UP A TROUGH IN THE EAST.
FOR MONDAY NIGHT...THERE COULD BE SOME SHOWERS AND THUNDERSTORMS IN
THE FAR SOUTHERN CWA IN NORTH CENTRAL KANSAS AS A LOW-LEVEL JET
DEVELOPS...WITH THE NOSE APPROACHING OUR SOUTHERN COUNTY WARNING
AREA. A STRONG STORM CAN NOT BE RULED OUT...BUT STORM PARAMETERS DO
NOT POINT TOWARD AN OVERWHELMING MOVE TOWARD MENTIONING SEVERE
WEATHER AT THIS TIME.
THE TROUGH SLIDING THROUGH ON TUESDAY IN THE NORTHERN/CENTRAL PLAINS
COULD HELP SPARK SOME SHOWERS AND THUNDERSTORMS FOR TUESDAY DURING
THE DAY ACROSS MAINLY OUR NEBRASKA COUNTIES...BUT AFTER THIS...A
SURFACE HIGH SLIDES AND WE SHOULD COOL OFF INTO THE 70S...STILL JUST
EAST OF THE DEVELOPING AND EXPANDING RIDGE...WITH ITS AXIS OVER THE
ROCKY MOUNTAINS.
THE RIDGE EXPANDS OVER OUR AREA AND WILL EFFECTIVELY SHUT OF THE
SPIGOT FOR A COUPLE OF DAYS...WHILE TEMPERATURES BEGIN TO MODERATE
ONCE AGAIN...TOWARD MORE NORMAL TEMPERATURES.
WE COULD GET SOME SHOWERS AND THUNDERSTORMS BY FRIDAY NIGHT WITH
ANOTHER LOW-LEVEL JET DEVELOPING...BUT STRONGER STORMS WILL PROBABLY
BE FARTHER NORTH WHERE THE NOSE OF THE JET WILL MORE LIKELY BE.
STORM CHANCES CONTINUE INTO THE WEEKEND AS A FEW WEAKNESSES IN THE
RIDGE ALLOW FOR SOME PERTURBATIONS TO POSSIBLY KICK UP A FEW
THUNDERSTORMS...BUT TEMPERATURES AT 700 MB APPROACHING 14 C INDICATE
THAT A HEALTHY CAP WILL BE IN PLACE AND COULD TAKE SOME WORK GETTING
THAT BROKEN. TEMPERATURES WARM UP TO SUMMER-TIME STANDARDS BY THE
WEEKEND WITH HIGHS IN THE MID 80S TO LOWER 90S.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 631 PM CDT SUN JUN 29 2014
KGRI AND KEAR WILL LIKELY BE DRY UNTIL AFTER SUNSET. A LOW LEVEL
JET WILL INCREASE AFTER SUNSET AND WE MAY SEE A THUNDERSTORM IN
THE VICINITY OF THE TWO TERMINALS. WILL KEEP THUNDER OUT OF THE
TAF UNTIL WE SEE WHERE THESE STORMS ACTUALLY DEVELOP. THE WIND
WILL REMAIN SOUTHERLY THROUGH THE NIGHT AND THEN TURN NORTHERLY
MONDAY MORNING BEHIND A SFC FRONT.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...WESELY
SHORT TERM...JCB
LONG TERM...HEINLEIN
AVIATION...WESELY
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
652 PM CDT SUN JUN 29 2014
.SHORT TERM...(TONIGHT THROUGH WEDNESDAY)
ISSUED AT 355 PM CDT SUN JUN 29 2014
CHANCE FOR SEVERE THUNDERSTORMS TONIGHT INTO MONDAY IS THE PRIMARY
FORECAST CONCERN.
AFTER MORNING THUNDERSTORMS ROLLED THROUGH PARTS OF EASTERN NEBRASKA
AND WESTERN IOWA...ATMOSPHERE HAD STABILIZED FOR A TIME INTO EARLY
AFTERNOON. HOWEVER LINGERING CLOUD COVER HAS EVAPORATED...ALLOWING
TEMPERATURES TO REBOUND INTO THE MIDDLE 80S MANY SPOTS. THIS
COMBINED WITH DEW POINTS IN THE LOWER 70S AND SOME COOLING ALOFT HAS
PRODUCED SURFACE-BASED CAPES EXCEEDING 3500 J/KG. 18Z SOUNDING AT
KOAX SHOWED 3692 J/KG OF SURFACE-BASED CAPE WITH ALMOST NO
INHIBITION. LAYER SHEAR...0-6KM...WAS 34KT...AND IS EXPECTED TO
INCREASE AS THE AFTERNOON WEARS ON. HOWEVER OUR 18Z SOUNDING SHOWS
LIFTING A MIXED-LAYER PARCEL YIELDS ONLY 1500 J/KG OF CAPE AND
INHIBITION RUNNING OVER 100. THUS MAY HAVE TO WAIT A WHILE BEFORE
CINH GOES AWAY AND HIGH INSTABILITY CAN BE REALIZED. A FEW AREAS OF
ISOLATED CONVECTION WERE NOTED AT MID AFTERNOON...BUT NONE ARE
SHOWING SIGNS OF GROWING AT THE MOMENT. MOST LIKELY AREA OF
INITIATION FOR MORE ROBUST DEVELOPMENT THIS AFTERNOON APPEARS TO BE
SETTING UP FROM CENTRAL NEBRASKA TO THE COLUMBUS...FREMONT AND
MISSOURI VALLEY AREAS. ENHANCED CUMULUS FIELD WAS STARTING TO EXPAND
HERE...WITH WEAK AREA OF FRONTAL CONVERGENCE AS PER RAP 19Z
INITIALIZATION. OTHER SUBTLE BOUNDARIES LEFT OVER FROM MORNING
STORMS COULD ALSO FOCUS STORMS THIS AFTERNOON. WHERE STORMS DO FIRE
THIS AFTERNOON...EXPECT RAPID DEVELOPMENT TOWARD STRONG/SEVERE
LEVELS IN HIGH INSTABILITY ENVIRONMENT. ORIENTATION OF LAYER SHEAR
VECTORS SUGGEST SOME SUPERCELL STRUCTURES WITH INITIAL DEVELOPMENT
OF STORMS WHICH SHOULD MOVE OFF TO THE EAST AND SOUTHEAST. CONTINUED
DEVELOPMENT AND INCREASING LOW LEVEL JET SUGGEST MCS DEVELOPMENT
WITH PROPAGATION TO THE SOUTHEAST THIS EVENING. EXPECT A HAIL AND
TORNADO THREAT WITH EARLY CONVECTION...THEN EVOLVING INTO A
HAIL...WIND AND HEAVY RAIN THREAT THROUGH THE EVENING.
EXPECT MOST OF THIS ACTIVITY TO MOVE OUT OF OUR AREA BY LATE
EVENING. THEN AN AREA OF LOW PRESSURE ROLLING OUT OF WESTERN KANSAS
ALONG FRONTAL BOUNDARY WILL ENHANCE LIFT OVER EASTERN NEBRASKA AND
AFTER MIDNIGHT...THEN SPREAD ACROSS WESTERN IOWA MONDAY MORNING.
LINGERING HIGH PRECIPITABLE WATER VALUES NEAR 2 INCHES POINT TO A
POTENTIAL OF HEAVY RAIN WITH ANY STORMS THROUGH MONDAY MORNING. SLOW-
MOVING COLD FRONT IS FORECAST TO LIMP SOUTH THROUGH MONDAY
AFTERNOON...AND CYCLONIC FLOW ALOFT COMBINED WITH WAVES RIPPLING
ALONG FRONT POINT TO REPEATED DEVELOPMENT OF MODERATE TO HEAVY RAIN
UNTIL FRONT CLEARS OUR SOUTHEAST LATE IN THE DAY.
AFTER FRONT SLIPS SOUTH OF THE FORECAST AREA MONDAY EVENING...WILL
CONTINUE OUR DRY FORECAST THROUGH TUESDAY MORNING. THEN A SHORTWAVE
ROTATING THROUGH THE NORTHERN PLAINS WILL PUSH A COLD FRONT INTO THE
AREA TUESDAY AFTERNOON WHEN ENHANCED INSTABILITY WILL LEAD TO
SCATTERED SHOWERS OR THUNDERSTORMS AS FAR SOUTH AS OMAHA. THESE
SHOULD BE DIURNALLY DRIVEN AND END AT SUNSET. TUESDAY WILL BE COOLER
AS 850 TEMPERATURES DROP INTO THE LOWER TEENS...THEN EVEN COOLER
WEDNESDAY WITH 850 TEMPS IN THE SINGLE DIGITS. MANY HIGHS BOTH DAYS
SHOULD HOLD IN THE 70S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 355 PM CDT SUN JUN 29 2014
LONG TERM PERIOD WILL START WITH MID LEVEL RIDGING BUILDING INTO THE
MIDDLE OF THE COUNTRY INTO THURSDAY...TAKING STORM TRACK TO OUR
NORTH. SURFACE HIGH PRESSURE AND ONLY SLOWLY RECOVERING 850
TEMPERATURES WILL KEEP HIGHS BELOW 80 THEN. A SHORTWAVE WILL THEN
ROLL INTO THE PLAINS FRIDAY INTO SATURDAY...BRINGING RAIN CHANCES
BACK TO OUR AREA BY FRIDAY NIGHT. COULD SEE SOME STORMS FIRE FRIDAY
AFTERNOON...BUT THE REAL FIREWORKS SHOULD HOLD OFF UNTIL THE EVENING
AND OVERNIGHT INTO SATURDAY. GFS SHOWS SYSTEM EXITING TO THE SOUTH
FOR SATURDAY NIGHT AND SUNDAY...BUT SEVERAL ENSEMBLE MEMBERS
INDICATE TIMING OF SHORTWAVE MAY BE A BIT FAST. THUS WILL CONTINUE
SMALL RAIN CHANCES INTO SUNDAY.
&&
.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 643 PM CDT SUN JUN 29 2014
SOMEWHAT DIFFICULT FCST FOR THE REST OF THIS EVENING. ENVIRONMENT
IS HIGHLY UNSTABLE WITH AMPLE SHEAR TO PRODUCE SVR STORMS WITH SEVERAL
OUTFLOW BOUNDARIES OBSERVED. AT THIS POINT...BELIEVE ANY OTHER
TSRA DEVELOPMENT THE NEXT SEVERAL HOURS WILL BE ISOLATED IN NATURE
OVER ERN NEB...THUS HAVE REMOVED TEMPO GROUPS THIS TAF ISSUANCE.
MEANWHILE...HAVE ADDED PROB30 GROUPS FOR POSSIBLE MORNING
CONVECTION PUSHING ACROSS THE AREA BTWN 12Z-18Z TIMEFRAME. LOW
CONFIDENCE THAT ANY TSRA ACTIVITY WILL CONTINUE MON AFTN...THUS
MENTION INCLUDED.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...DERGAN
LONG TERM...DERGAN
AVIATION...DEE
AREA FORECAST DISCUSSION
NWS HASTINGS NE
313 PM CDT SAT JUN 28 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 302 PM CDT SAT JUN 28 2014
MAIN FORECAST CONCERNS WILL BE CHANCES FOR THUNDERSTORMS AND
TEMPERATURES.
SURFACE ANALYSIS SHOWS A BOUNDARY IN THE EASTERN PART OF THE
FORECAST AREA EARLY THIS AFTERNOON. SATELLITE HAS SOME CUMULUS
FORMING MAINLY IN THE NORTHERN PART OF NEBRASKA WITH A FEW
FURTHER WEST AS WELL.
AN UPPER LEVEL WAVE IS MOVING THROUGH THE FORECAST AREA LATE THIS
AFTERNOON AND THIS EVENING. MODELS SHOW THE WAVE THROUGH THE AREA
DURING THE EVENING AND THE SURFACE BOUNDARY WEAKENING.
THUNDERSTORMS ARE EXPECTED TO DEVELOP LATE THIS AFTERNOON NEAR THE
WEAKENING BOUNDARY AND THE UPPER WAVE. THE HRRR KEEPS THE
PRECIPITATION MAINLY NORTH OF THE AREA WHILE THE 4KM WRF HAS IT A
LITTLE FURTHER SOUTH. BOTH OF THEM KEEP THE PRECIPITATION MAINLY
IN THE EAST OR NORTHEAST. THE MUCAPE IS MAINLY AROUND 3000 J/KG
SO THERE COULD BE SOME STRONG TO SEVERE STORMS. THE STORMS SHOULD
MOVE OUT OF THE AREA BEFORE MIDNIGHT.
ANOTHER UPPER LEVEL WAVE MOVES INTO THE AREA LATE TONIGHT. IN
ADDITION THERE IS A WEAK LOW LEVEL JET. THERE COULD BE A FEW
SHOWERS AND THUNDERSTORMS IN THE FAR WEST LATE TONIGHT.
EXPECT THERE TO BE A BREAK DURING THE MORNING SUNDAY BEFORE MORE
THUNDERSTORMS DURING THE AFTERNOON. THE UPPER WAVE CONTINUES TO
MOVE THROUGH THE AREA DURING THE DAY. THE MUCAPE IS OVER 4000 J/KG
DURING THE AFTERNOON. EXPECT THUNDERSTORMS TO DEVELOP IN THE EARLY
AFTERNOON. THESE STORMS ARE EXPECTED TO BECOME SEVERE.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 302 PM CDT SAT JUN 28 2014
THE BIGGEST ISSUE WILL BE POTENTIAL ONGOING THUNDERSTORMS SUNDAY
EVENING...AND THE CHANCES OF SEVERE WEATHER.
UPPER LEVEL FLOW WILL BE QUASI-ZONAL...BUT BROADLY CYCLONIC FOR
SUNDAY AS AN UPPER LEVEL JET MAKES ITS WAY ACROSS THE NORTHWEST
INTO THE NORTHERN PLAINS. A CLOSED LOW WILL BE WELL NORTH OVER
MANITOBA WHILE FLAT SUBTROPICAL RIDGING WILL OCCUR ACROSS THE
SOUTHERN TIER. WE MAY CATCH THE SOUTHERN FRINGES OF THE
AFOREMENTIONED UPPER LEVEL JET TOWARD THE NORTHER CWA. A SURFACE
COLD FRONT WILL CONTINUE TO SLOWLY SAG SOUTH AND EAST...BUT WILL
BE THE FOCUS FOR CONVECTION BY SUNDAY EVENING. WITH A BULK SHEAR
MAGNITUDE OF 35 TO 45 KTS AND CAPE LIKELY TO BE GREATER THAN 3000
J/KG FOR MUCH OF THE CWA...SEVERE WEATHER APPEARS TO BE LIKELY AS
DISCREET SUPERCELLS LIKELY FORMING INTO A LINE THAT WILL HELP
PUSH THE FRONT SOUTH WITH ITS OUTFLOW. THIS LOOKS LIKE AN EARLY
SHOW WITH INCREASED DEWPOINTS ENCOURAGING THUNDERSTORM
DEVELOPMENT NEAR THE SURFACE FRONT...AGAIN WITH OUTFLOW
ENCOURAGING A PUSH TO THE SOUTH...PROBABLY ENDING THE CHANCE OF
SEVERE WEATHER BY EARLY TO MID-EVENING. SREF SEVERE PARAMETERS
EXPLODE IN THE AFTERNOON...BUT WANE QUICKLY BY EVENING. TORNADO
PARAMETERS ARE ALSO SLIGHTLY ELEVATED...SO AN ISOLATED TORNADO IS
NOT OUT OF THE QUESTION...BUT NOT AS LIKELY INTO THE EVENING. SOME
ELEVATED STORMS COULD POP UP...ESPECIALLY NORTH LATER ON SUNDAY
NIGHT...BUT THE SUPPORT FOR SEVERE WEATHER WILL BE LARGELY GONE BY
THEN.
BY MONDAY...THE SURFACE FRONT SHOULD BE FAR ENOUGH SOUTH WITH ENOUGH
SINKING AIR TO PREVENT ANY CONVECTION OVER OUR AREA...ALTHOUGH IT
MAY BE A BIT BREEZY...CONSIDERING POTENTIAL HEIGHT
RISES.
WE TRANSITION TO NORTHWEST FLOW LATER IN THE FORECAST
TUESDAY/WEDNESDAY. A SHORTWAVE TROUGH IS FORECAST TO MOVE THROUGH
WITHIN THE NORTHWEST FLOW AS A RIDGE BUILDS IN THE WEST AND TROUGH
IN THE EAST. WE SEEM TO BE TRANSITIONING TO A WARMER AND DRY PERIOD
AS THE HIGH BECOMES MORE ESTABLISHED...MOSTLY SUPPRESSING RAIN
DEVELOPMENT AND WARMING TEMPERATURES ALOFT. HOWEVER...THERE IS SOME
THAT THE EASTERN EDGE OF THE HIGH COULD WEAKEN AND
PERHAPS ALLOW SOME WAVES TO AFFECT US...ESPECIALLY IN OUR EAST.
MODELS HAVE BACKED OFF OF PRECIPITATION FOR WEDNESDAY
NIGHT...PUSHING THE NEXT SHOT AT SLIGHT CHANCES OF THUNDERSTORMS TO
THURSDAY NIGHT WITH THE AID OF A DEVELOPING LOW-LEVEL JET.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1218 PM CDT SAT JUN 28 2014
THERE IS AN OUTSIDE CHANCE FOR A FEW THUNDERSTORMS NEAR THE KGRI
TERMINAL AREA...BUT EXPECT THAT ACTIVITY SHOULD BE TO THE EAST OF
THE TERMINAL. EXPECT VFR CONDITIONS THROUGH THE NIGHT AND INTO
SUNDAY MORNING.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...JCB
LONG TERM...HEINLEIN
AVIATION...JCB
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
722 AM CDT SAT JUN 28 2014
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 300 AM CDT SAT JUN 28 2014
HEAVY RAIN POTENTIAL TODAY AND SEVERE WEATHER/HEAVY RAIN THREAT
SUNDAY AFTERNOON/SUNDAY NIGHT MAIN FORECAST CONCERN IN SHORT TERM.
EARLY MORNING SATELLITE IMAGERY SHOWED NEGATIVELY TILTED UPPER
TROUGH EXTENDING THROUGH NEBR AND INTO CNTRL KS WITH LARGE
CONVECTIVE AREA ON ITS SERN FLANK WITH SECOND AREA LIFTING N
ACROSS THE DAKOTAS. LOW LEVEL JET WILL CONTINUE TRANSPORTING
MOISTURE INTO ONGOING CONVECTIVE BAND AND PROPAGATION/CORFIDI
VECTORS FORECAST TO REMAIN SHORT. THUS HEAVY RAIN REMAINS A
THREAT...ESPECIALLY THIS MORNING AND MAINLY CNTRL/SERN SECTIONS.
THREAT WOULD APPEAR TO SHIFT MORE INTO SERN ZONES LATER TODAY AS
QG FORCING SHIFTS TO THE FAR SE...BUT SOME REDEVELOPMENT CANNOT BE
RULED OUT WRN ZONES NEAR WEAKENING COOL FRONT ESPECIALLY IF BREAKS
CAN DEVELOP PROVIDING A LITTLE ADDITIONAL BOOST TO CAPE VALUES.
LONG STORY SHORTENED...WILL CONTINUE FLASH FLOOD WATCH. MORE
DISCUSSION BELOW IN HYDRO SECTION. WILL COUNT ON A FEW...BUT NOT
TOO MANY...BREAKS TO DEVELOP LATER TODAY TO ALLOW MOST READINGS TO
REACH NEAR 80. GENERALLY ON COOLER SIDE OF GUIDANCE AND LITTLE/NO
CHANGE FROM PRIOR FORECAST.
AMOUNT...IF ANY...LATE AFTN/EARLY EVENING DEVELOPMENT ON
WEAKENING COOL FRONT WILL PROBABLY PROVIDE MAIN CONVECTIVE CHANCE
TO FORECAST AREA TONIGHT. THIS MAY INFLUENCE WHETHER CURRENT
FLASH FLOOD WATCH IS EXTENDED LATER TODAY OR DROPPED AS
CONVECTIVE TRENDS THIS MORNING PLUS SHORT TERM FORECAST BECOMES
BETTER ANALYZED. HOWEVER...LATER TONIGHT PRECIP CHANCES SEEM TO
DECREASE EVEN MORE AS MUCH LESS STRONG/WIDESPREAD HIGH PLAINS
ACTIVITY IS EXPECTED TODAY TO HOLD TOGETHER LATER TONIGHT.
ALTHOUGH A EARLY DAY TSTM CANNOT BE RULED OUT SUNDAY ALONG
BOUNDARY NEAR WRN ZONES AS MOISTURE RETURNS...CHANCES INCREASE
MARKEDLY IN THE LATE AFTN HOURS AS HEATING SHOULD BE MUCH STRONGER
THAN PAST FEW DAYS. MOST AREAS SHOULD APPROACH IF NOT EXCEED 90
DEGREES. ALL MODES OF SEVERE WEATHER REMAIN POSSIBLE...SPECLY NRN
ZONES...AS AREA REMAINS JUST SOUTH OF STRONG WRLY JET OVER SD
PROVIDING IMPRESSIVE SHEAR VALUES TO GO ALONG WITH SBCAPES OF 4K
OR MORE J/KG. EVOLUTION INTO THE EVENING AND THEN OVERNIGHT HOURS
A LITTLE LESS CERTAIN...AS SOME INDICATIONS THAT CONVECTION
DEVELOPING NEAR BOUNDARY INTO SCNTRL NEBR COULD SPREAD ACROSS SERN
ZONES THRU 06Z POSSIBLY INFLUENCING IF NOT HINDERING LATE NIGHT
ACTIVITY FARTHER N. ACTIVITY NRN ZONES COULD EXPERIENCE DECENT
ECHO TRAINING NEAR AND AFTER 06Z AS STEEP MID LEVEL LAPSE RATES
BUILD INTO SERN NEBR TOWARD 12Z MONDAY POSSIBLY LIMITING SWD
DEVELOPMENT/MOVEMENT. IN OTHER WORDS...A HEAVY RAIN THREAT WILL
LIKELY EVOLVE AFTER IF NOT IN CONJUNCTION WITH SVR RISK...ALTHOUGH
WHERE IT SETS UP IN FLUX. WILL CONTINUE TO HIT BOTH SVR AND HEAVY
RAIN THREATS HARD IN HWO. INCREASED POPS NRN ZONES ESPECIALLY
SUNDAY NIGHT AS THAT AREA SEEMED MOST LIKELY.
ALSO INCREASED POPS NERN/ERN AREAS MONDAY...ESPECIALLY EARLY IN
THE MORNING AS SOME LINGERING POST FRONT PRECIP INDICATED BY
00Z NAM/GFS/ECMWF WITH LATTER 2 MODELS FORECASTING A MINOR WAVE
ROTATING ACROSS SD ON SOUTH SIDE OF CANADIAN UPPER LOW. LITTLE
CHANGES TO TEMPS...NORTH AND NORTHEAST ZONES SHOULD BE
COOLER...ESPECIALLY IF PRECIP LINGERS PAST MIDDAY...BUT SOME
RECOVERY POSSIBLE SOUTH AHEAD OF FRONT.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 300 AM CDT SAT JUN 28 2014
GENERALLY COOLER AND DRY WEATHER SHOULD PREVAIL TUESDAY WITH ONLY
A MODEST TEMP RECOVERY EXPECTED WEDNESDAY AS NORTHWESTERLY FLOW
SHOVES THE WARMER/MORE MOIST AIR TO OUR SOUTH. ALTHOUGH PRECIP
CHANCES DO NOT APPEAR THAT GREAT...THEY DO INCREASE SOME LATER IN
THE WEEK AS MOISTURE/INSTABILITY RETURN AS UPPER RIDGE BEGINS
BUILDING EWD. HOWEVER...CAP MAY INCREASE AS FAST AS UPPER HEIGHTS
BUILD TO MORE SUMMER-LIKE VALUES. PATTERN DOES LOOK MUCH LESS
ACTIVE...HOWEVER...AND TEMPERATURES LOOK TO BE SHIFTING MORE TO
ABOVE NORMAL VALUES.
&&
.AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 720 AM CDT SAT JUN 28 2014
VARIABLE CONDITIONS ARE ONCE AGAIN IN PLACE OVER THE AREA AT THE
START OF THE PERIOD WITH A DIMINISHING AREA OF SHOWERS NEAR THE
SOUTHERN NEBRASKA BORDER. A SHARP MID LEVEL TROUGH STRETCHING FROM
THE WESTERN DAKOTAS THROUGH CENTRAL KANSAS AT 12Z IS EXPECTED TO
HELP TRIGGER ANOTHER ROUND OF CONVECTION BY THIS AFTERNOON AND
INTO THE EVENING AS A COLD FRONT OVER THE NORTHERN PLAINS DROPS
INTO EASTERN NEBRASKA. SHORT RANGE RAP MODEL WANTS TO FOCUS MOST
OF THE CONVECTIVE ACTIVITY EAST AND SOUTH OF THE TAF SITES. HAVE
GENERALLY TRENDED FORECAST TOWARD THIS IDEA WITH PRIMARILY VFR
CONDITONS THROUGH THE PERIOD. SINCE KOMA WILL BE ON THE WESTERN
EDGE OF THIS ACTIVITY DID PUT IN PROB GROUP THERE FOR THE LATE
AFTERNOON.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...FLASH FLOOD WATCH UNTIL 7 PM CDT THIS EVENING FOR NEZ015-018-
030>034-042>045-050>053-065>068-078-088>093.
IA...FLASH FLOOD WATCH UNTIL 7 PM CDT THIS EVENING FOR IAZ043-055-056-
069-079-080-090-091.
&&
$$
SHORT TERM...CHERMOK
LONG TERM...CHERMOK
AVIATION...FOBERT
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1250 AM CDT SAT JUN 28 2014
.SYNOPSIS...
ISSUED AT 209 PM CDT FRI JUN 27 2014
A DEEP UPPER LEVEL LOW OFF THE WASHINGTON COAST MOVES
INLAND THROUGH SRN CANADA SUNDAY AND SENDS A STRONG PACIFIC COLD
FRONT THROUGH WRN AND NCNTL NEB. THIS WILL BRING COOLER AIR INTO THE
FCST AREA MONDAY THROUGH WEDNESDAY. WARMER WEATHER DEVELOPS THURSDAY
AND FRIDAY AS A MORE SUMMER-LIKE PATTERN DEVELOPS.
RAIN CHANCES DECREASE AFTER THE PASSAGE OF THE COLD FRONT SUNDAY.
UNTIL THEN THUNDERSTORMS AND SEVERE WEATHER WILL BE POSSIBLE.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 209 PM CDT FRI JUN 27 2014
TONIGHT AND SATURDAY...ABBREVIATED DISCUSSION AS WE ARE CURRENTLY
WATCHING CONVECTIVE TRENDS. MULTIPLE MODES OF CONVECTION CAN BE
ANTICIPATED ACROSS WESTERN AND NORTH CENTRAL NEBRASKA LATE THIS
AFTERNOON AND THROUGH THE OVERNIGHT. THE POTENTIAL OF SEVERE
STORMS WITH LARGE HAIL...DAMAGING WIND...AND GUSTY OUTFLOW EXISTS.
IN ADDITION...HEAVY RAINFALL MAY ACCOMPANY STORMS THIS EVENING AND
OVERNIGHT AS CELLS MERGE AND CONVECTIVE COMPLEXES FORM. THE
FORECAST IN THE SHORT TERM RELIES ON A BLEND OF THE 27.12Z NAM AND
NEAR TERM CONVECTION ALLOWING MODELS. THE OVERALL IDEA IS THAT
MULTIPLE THUNDERSTORMS WILL DEVELOP ACROSS THE REGION THIS
AFTERNOON AND EVENING AS A SHORTWAVE IMPULSE ASSOCIATED WITH A
NEGATIVELY TILTED TROUGH EJECTS NORTHEAST ATOP THE CENTRAL PLAINS
FROM SOUTH CENTRAL COLORADO. MVFR STRATUS HAS BACKED INTO THE
EASTERN THIRD OF THE FORECAST AREA EARLY TODAY...LIMITING LOW
LEVEL LAPSE RATES AND PROVIDING FOR A FAIRLY SIGNIFICANT CAP /SEE
18Z SPECIAL KLBF SOUNDING/. WITH THAT BEING SAID...THE STRATUS IS
SLOWLY BREAKING...WITH A BKN DECK NOW GENERALLY ALONG AND EAST OF
A KOGA TO KONL LINE. THE ATMOSPHERE SHOULD FURTHER DESTABILIZE AS
THE IMPULSE CLOSES AND ADDITIONAL CLEARING OCCURS. RAP GENERATED
SBCAPES APPROACH 3000 J/KG BY LATE AFTERNOON EAST OF A IMPERIAL TO
NORTH PLATTE TO BROKEN BOW LINE...WITH UP TO 2000 J/KG ACROSS
WESTERN NEBRASKA AND MUCH OF THE SANDHILLS REGION. ONCE THE CAP
ERODES...STORMS ARE LIKELY TO FORM IN TWO GENERAL AREAS...FIRST
ACROSS WESTERN NEBRASKA AND NORTHEAST COLORADO...IN THE VICINITY
OF A NORTH TO SOUTH SFC TROUGH EXTENDING FROM A SFC LOW CENTERED
IN FAR WEST CENTRAL KANSAS. IN THIS AREA THE MAIN THREAT WILL BE
HAIL INITIALLY...BUT THEN TRANSITION TO A WIND THREAT AS THE
STORMS MERGE INTO A CONVECTIVE LINE AND DCAPES APPROACH 1000 J/KG.
THIS ACTIVITY PROJECTED TO LIFT EAST NORTHEAST ACROSS MUCH OF THE
SANDHILLS THIS EVENING.
THE SECOND AREA OF CONVECTION WILL BE ANTICIPATED INVOF THE
TRIPLE POINT THAT IS SHOWN TO SLOWLY BULGE NORTHEAST INTO NORTHERN
KANSAS/SOUTHWEST NEBRASKA. STORMS IN THIS AREA MAY PRODUCE A BRIEF
TORNADO AS THE SUPERCELLS REMAIN SEMI-DISCRETE. THE TORNADO THREAT
WILL BE SHORT-LIVED HOWEVER AS THE STORMS SHOULD QUICKLY EVOLVE INTO
MULTIPLE CLUSTERS. IN ADDITION TO THE BRIEF TORNADO
THREAT...HAIL...SOME OF WHICH MAY BE VERY LARGE...WILL BE POSSIBLE
AS A SIGNIFICANT CONTRIBUTION OF CAPE RESIDES IN THE -10 TO -30C
LAYER...BUT ONCE AGAIN THE VERY LARGE HAIL THREAT WILL BE MAINLY
TIED DURING THE INITIAL SEMI-DISCRETE SUPERCELL STAGE. THIS
ACTIVITY FROM SOUTHWEST NEBRASKA IS PROJECTED TO MERGE TO THE
NORTHEAST AND WILL PRODUCE GUSTY WIND AND HEAVY RAINFALL AS PWATS
INCREASE TO THE 1.25-1.50" RANGE. MORE ON THE RAIN THREAT BELOW.
THE FORECAST GENERALLY CALLS FOR WIDESPREAD 50-60% POPS OVER MUCH OF
THE SANDHILLS...WESTERN...SOUTHWEST AND SOUTH CENTRAL NEBRASKA THIS
EVENING...WITH POPS INCREASING ACROSS NORTH CENTRAL NEBRASKA LATE
THIS EVENING AND OVERNIGHT. DIDN/T WANT TO GO MUCH HIGHER AS
CONVECTION...WELL IT/S CONVECTION.
CONCERNING THE HEAVY RAINFALL POTENTIAL...THE POTENTIAL MCS/S/ MAY
PROVE TO BE A FOCUS FOR HEAVY RAINFALL OVERNIGHT AS A COLD POOL
DEVELOPS AND POSSIBLY REINFORCING A WEST TO EAST BOUNDARY...FOR
WHICH REDEVELOPMENT/TRAINING WOULD OCCUR AS THE LLJ STRENGTHENS.
AGAIN PWATS INCREASE TO OVER 1.25" ATOP EASTERN PORTIONS OF THE
CWA...WITH THE POTENTIAL OF 1.50" OVER FRONTIER AND CUSTER
COUNTIES. WE MAY SEE A LOCALIZED FLOOD THREAT.
FOR SATURDAY...LINGERING SHOWERS AND STORMS ARE POSSIBLE ACROSS
NORTH CENTRAL NEBRASKA AS THE FOCUS FOR STORMS SHIFTS EAST WITH THE
BEST LOW LEVEL CONVERGENCE. TEMPERATURES WILL BE PLEASANT...WITH
WIDESPREAD 80S ANTICIPATED.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 209 PM CDT FRI JUN 27 2014
SATURDAY NIGHT THROUGH MONDAY...THUNDERSTORMS CHANCES REVOLVE AROUND
THE PROGRESSION OF RETURN MOISTURE AND A PACIFIC COLD FRONT FCST TO
ARRIVE SUNDAY. RETURN MOISTURE SATURDAY NIGHT MIGHT PRODUCE ENOUGH
INSTABILITY FOR ISOLATED TSTMS ACROSS THE NORTHEAST ZONES. THE
BETTER CHANCES OCCUR SUNDAY AFTN/NIGHT AS THE PACIFIC FRONT SAGS
THRU THE FORECAST AREA FROM SOUTHWEST TO NORTHEAST. AREAS EAST OF
HIGHWAY 83 ARE MORE FAVORED AT THIS TIME.
A FAIRLY STRONG THERMAL RIDGE/CAP DEVELOPS SUNDAY AHEAD OF THE COLD
FRONT WITH H700MB TEMPERATURES RISING TO 15C ACROSS SWRN NEB. THIS
SHOULD SUPPORT HIGHS IN THE LOWER 90S AHEAD OF THE FRONT. GIVEN THE
THE PROXIMITY OF AN UPPER LOW OVER MANITOBA...HEATING AND
MOISTURE...HIGH CAPE AND STRONG WINDS ALOFT SUPPORT SEVERE TSTM
DEVELOPMENT AS THE CAP WEAKENS SUNDAY AFTN AND EVENING. POPS TAPER
ACROSS SWRN NEB WITH THE CAP IN PLACE UNTIL 06Z OR LATER.
MONDAY NIGHT THROUGH FRIDAY...A SUBTROPICAL UPPER LEVEL RIDGE BUILDS
ACROSS THE MID SOUTH AND THEN AMPLIFIES SOMEWHAT ACROSS THE ROCKIES.
RETURN MOISTURE DEVELOPS WEDNESDAY AND BEYOND. GIVEN THE WARMING
ALOFT...SLOW MOISTURE RETURN AND WEAKENING WIND FIELDS...ISOLATED
POPS ARE LIMITED TO THE NIGHTTIME PERIOD. THE MODELS SUGGEST H500MB
TEMPS WOULD RISE TO -6C TO -8C WHICH WOULD GENERALLY CAP DAYTIME
CONVECTION. TEMPERATURES RISE FROM AROUND 80 TUESDAY TO THE 90S BY
FRIDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1235 AM CDT SAT JUN 28 2014
THUNDERSTORMS ARE EXITING THE AREA WITH VISUAL FLIGHT RULES AT
TERMINALS KLBF AND KVTN. ISOLATED SHOWERS MAY BE SEEN OVER THE
NEXT COUPLE OF HOURS. OTHERWISE...OVERNIGHT MAIN CONCERN IS FOG OR STRATUS
DEVELOPMENT THROUGH 09Z WITH FOG INTRODUCED IN BOTH TERMINAL
FORECASTS. SHORT TERM MODELS SHOW DRIER AIR ADVECTING IN...YET AS
TEMPERATURES FALL TEMP AND DEWPOINT SPREAD GAP WILL CLOSE. THEN TIME
SECTIONS SUGGEST BETTER CHANCE FOR STRATUS INTO THE VALENTINE AREA
AND WILL MONITOR FOR LATER UPDATES.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...CDC
SHORT TERM...JACOBS
LONG TERM...CDC
AVIATION...KECK
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1023 PM EDT SUN JUN 29 2014
.SYNOPSIS...
HIGH PRESSURE WILL MOVE OFF THE MID-ATLANTIC COAST THROUGH THE
MIDDLE OF THE WEEK BRINGING A SLOW WARMING TREND. AN AREA OF
TROPICAL LOW PRESSURE DEVELOPING OFF THE FLORIDA COAST MAY LIFT TO
THE NORTH LATE IN THE WEEK BRINGING INCREASING RAIN CHANCES. A COLD
FRONT WILL STALL AS IT APPROACHES THE AREA LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
AS OF 1030 PM SUNDAY...CIRRUS FROM DYING CONVECTION IN THE FOOTHILLS
AND WESTERN PIEDMONT IS SPILLING OVER THE UPPER RIDGE AND MOVING
SOUTHWARD ACROSS THE CENTRAL CAROLINAS. TYPICALLY THIN CIRRUS LIKE
THIS LOOKS A LOT WORSE ON INFRARED SATELLITE IMAGERY THAN IT DOES
FROM THE GROUND...SO I WILL MAINTAIN SKY COVER FORECASTS BELOW 15
PERCENT OVERNIGHT WHICH YIELDS "CLEAR" IN THE FORECAST PHASE-OLOGY.
WINDS HAVE ALREADY DROPPED BELOW 5 KNOTS AT ALL AIRPORT ASOS/AWOS
SITES AWAY FROM THE BEACHES. I HAVE TWEAKED LOWS DOWN SLIGHTLY
ACROSS SE NORTH CAROLINA WITH NO CHANGES ELSEWHERE. PREVIOUS
DISCUSSION FROM 730 PM FOLLOWS...
SURPRISINGLY MILD TEMPERATURES ARE EXPECTED TONIGHT AS 1023 MB HIGH
PRESSURE OFF THE MID-ATLANTIC COAST EXTENDS A RIDGE AXIS ACROSS THE
CAROLINAS. OUR FORECAST LOWS ARE IN THE MID TO UPPER 60S AWAY FROM
THE BEACHES. AT WILMINGTON OUR FORECAST LOW (67 DEGREES) IS IN THE
LOWEST 17 PERCENTILE FOR THIS DATE AND 5 DEGREES BELOW NORMAL.
DAYTIME CUMULUS WERE LIMITED TO THE VICINITY OF THE SEABREEZE
BOUNDARY THIS EVENING...MAINLY ACROSS SOUTH CAROLINA WHERE DEWPOINTS
WERE HIGHEST. DRY AIR ASSOCIATED WITH SUBSIDENCE WITHIN THE HIGH
PRESSURE TO OUR NORTH MIXED DEWPOINTS DOWN INTO THE UPPER 50S ACROSS
MUCH OF NORTH CAROLINA INTO INTERIOR NORTHEASTERN SOUTH CAROLINA.
CLEAR SKIES SHOULD PREVAIL TONIGHT WITH PRETTY DECENT RADIATIONAL
COOLING CONSIDERING THE AIRMASS AND TIME OF YEAR. FOG POTENTIAL IS
QUITE LOW OVERALL...BUT THE PEE DEE REGION OF SOUTH CAROLINA AND
ALONG THE SANTEE RIVER PROBABLY HAVE THE HIGHEST POTENTIAL WITH
FORECAST SOUNDINGS FROM THE NAM AND RUC SHOWING SUFFICIENT MOISTURE
PRESENT THROUGH 800-1000 FEET AGL WITH DRYING ALOFT. THE GFS
SOUNDINGS ARE DRIER IN THE LOW-LEVELS WHICH WOULD PRECLUDE FOG.
OUR INCREASINGLY TROPICAL LOW EAST OF FLORIDA IS NOW ALMOST 400
MILES SOUTH OF CAPE FEAR AND SHOULD STALL OVER THE NEXT 12-24 HOURS.
THE OUTERMOST CLOUD BANDS ASSOCIATED WITH THIS FEATURE WILL REMAIN
TO OUR SOUTH TONIGHT WITH NO IMPACTS LOCALLY.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
AS OF 300 PM SUNDAY...SEASONABLE AND QUIET WEATHER FOR THE SHORT
TERM AS THE CALENDAR TICKS INTO JULY. THE SENSIBLE WEATHER WILL BE
CONTROLLED BY HIGH PRESSURE DRIFTING OFF THE MID-ATLANTIC
COAST...AND A MID-LEVEL RIDGE BLOSSOMING FROM THE GULF COAST. ON
MONDAY...MID-LEVEL RIDGE AXIS WILL BE ALIGNED NEARLY
OVERHEAD...SWEEPING OFF TO THE EAST ON TUESDAY. ALTHOUGH THE RIDGE
MOVES EAST ON TUESDAY...THICKNESSES WILL ACTUALLY BE A BIT HIGHER
THAN WHAT IS EXPECTED ON MONDAY. THIS IS IMPORTANT BECAUSE ALTHOUGH
COLUMN MOISTURE INCREASES FROM MONDAY TO TUESDAY...INCREASED
SUBSIDENCE WILL SOMEWHAT OFFSET THE CONVECTIVE POTENTIAL TUESDAY.
STILL...ISOLATED TSTMS WILL BE POSSIBLE TUESDAY...WHILE MONDAY IS
EXPECTED TO REMAIN DRY. TEMPS WILL SLOWLY CLIMB EARLY WEEK...WITH
HIGHS AROUND 90 EXPECTED MONDAY...LOW 90S ON TUESDAY. LOWS MONDAY
NIGHT WILL DROP TO AROUND 70 AWAY FROM THE BEACHES...BUT ONLY INTO
THE LOW/MID 70S TUESDAY NIGHT AS SOUTHERLY RETURN FLOW DEVELOPS
AROUND THE OFFSHORE HIGH PRESSURE.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 300 PM SUNDAY...H5 RIDGE PATTERN ACROSS THE SOUTHEAST WILL
BREAK DOWN DURING THE EXTENDED AS A SHORT WAVE TROUGH SHIFTS EAST
OF THE MID-WEST AND INTO NEW ENGLAND BY THE END OF THE WEEK. OTHER
THAN SOME TYPICAL SUMMERTIME DIURNAL CONVECTION ALL EYES WILL BE
ON THE POTENTIAL DEVELOPMENT OF A TROPICAL SYSTEM OFF THE
SOUTHEAST UNITED STATES COAST. THERE IS NO CONSISTENCY EVIDENT IN
THE MODELS AT THIS TIME WITH THE NAM FAIRLY AGGRESSIVE AND ECMWF
TRACKING THE STORM OFF THE NC COAST FRIDAY. TOO MANY VARIABLES AND
INCONSISTENCIES EXIST AT THIS TIME...THUS LOW CONFIDENCE FORECAST
CONTINUES IN THE EXTENDED. MAX/MIN TEMPERATURES THROUGH THE PERIOD
WILL BE AT OR JUST ABOVE NORMAL WED/THU...WHILE THE GFS IS
POSSIBLY A CATEGORY TOO HIGH FOR MAX TEMPS FRI AND SAT.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
AS OF 00Z...VFR CONDITIONS EXPECTED AT ALL TAF SITES OVERVIEW.
WILL MENTION JUST A TEMPO AT FLO AFTER 08Z FOR MVFR IN BR AS MODEL
SOUNDING DOES SHOW SOME LOW LEVEL MOISTURE IN THE LOWER PORTION OF
THE COLUMN SO WILL JUST MENTION TEMPO TO COVER. OTHERWISE MODELS ARE
SOMEWHAT DRIER IN THE LOW LEVEL FOR THE OVERNIGHT PERIOD. LATEST SAT
IR DOES SHOW CIRRUS DEBRIS CLOUDS WORKING EWD AND THIS WOULD IMPACT
THE REGION OVERNIGHT IN THE FORM OF HIGH CLOUDS WHICH WILL BECOME
SCATTERED TO BROKEN OVER THE TERMINALS OVERNIGHT INTO MONDAY. WINDS
WILL SLACKEN OFF OVERNIGHT TO LIGHT AND VARIABLE AND BECOME MORE E
TO NE THROUGHOUT THE DAY MONDAY AND VEERING TO THE SE ACROSS THE
MYRTLES DURING THE AFTERNOON AS THE SEA BREEZES MOVES ACROSS.
EXTENDED OUTLOOK...AFTERNOON AND EVENING SHOWERS EXPECTED THROUGH
THE PERIOD POSSIBLY CREATING PERIODS OF MVFR/IFR. OTHERWISE EXPECT
VFR. SOME UNCERTAINTY WITH POSSIBLE TROPICAL SYSTEM INTERACTION
WEDNESDAY THROUGH FRIDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 PM SUNDAY...VERY FEW CHANGES ARE NEEDED TO THE FORECAST
LATE THIS EVENING. PREVIOUS DISCUSSION FROM 730 PM FOLLOWS...
LOW PRESSURE HAS DRIFTED TO A POSITION ABOUT 400 MILES SOUTH OF CAPE
FEAR THIS EVENING. THIS HAS MADE WAY FOR 1023 MB HIGH PRESSURE OFF
THE MID-ATLANTIC COAST TO BUILD ACROSS THE INTERIOR CAROLINAS. EAST
TO NORTHEAST WINDS BETWEEN THIS HIGH AND THE LOW EAST OF FLORIDA
WILL CONTINUE THROUGH THE NIGHT...WITH GRADUALLY DIMINISHING WIND
SPEEDS EXPECTED AS THE PRESSURE GRADIENT WEAKENS. THE LONG ONSHORE
FLOW HAS BUILT SEAS TO AS HIGH AS 4 FEET WITHIN 20 MILES OF
SHORE...ESPECIALLY EAST OF CAPE FEAR. SEAS CURRENTLY CONSIST OF A
5-SECOND NORTHEAST WIND WAVE PLUS A 9-SECOND SOUTHEAST SWELL.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 300 PM SUNDAY...PRETTY QUIET MARINE CONDITIONS DURING THE
SHORT TERM...EVEN AS WINDS FLUCTUATE THROUGH MANY COMPASS
DIRECTIONS. HIGH PRESSURE MOVING OFF THE MID-ATLANTIC COAST DRIVES
NE WINDS AROUND 10 KTS ON MONDAY...BUT AS THIS HIGH PUSHES OFFSHORE
THE GRADIENT WILL WEAKEN...AND WINDS WILL BECOME VARIABLE UNTIL
EVENTUALLY BECOMING SW AROUND 10 KTS LATE IN THE PERIOD. SEAS WILL
BE DRIVEN BY A RESIDUAL GROUND SWELL AND A 5 SEC WIND
CHOP...CREATING 2-3 FT SEAS BOTH DAYS.
LONG TERM /WEDNESDAY THROUGH FRIDAY/...
AS OF 300 PM SUNDAY...SOUTHERLY FLOW IS EXPECTED TO PREVAIL
WEDNESDAY INTO WEDNESDAY NIGHT...WITH BACKING TO THE SOUTHEAST AND
INCREASING SPEEDS DURING THURSDAY. BIG QUESTION MARKS REMAIN
THEREAFTER DEPENDING ON THE EVOLUTION OF THE DISTURBED WEATHER OFF
THE GA/FL COASTS. HAVE NUDGED SEAS UP A FOOT FROM THE PREVIOUS
FORECAST AS THE FETCH WILL LIKELY DIRECT MORE ENERGETIC WAVES
TOWARD THE COAST. SMALL CRAFT CONDITIONS ARE POSSIBLE BY THE END
OF THE WEEK...AGAIN ALL DEPENDING ON WHAT HAPPENS WITH THE
AFOREMENTIONED AREA OF DISTURBED WEATHER.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...JDW
NEAR TERM...TRA
SHORT TERM...JDW
LONG TERM...SRP
AVIATION...MAC
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
947 PM EDT SUN JUN 29 2014
.SYNOPSIS...
LOW PRESSURE OFF THE SOUTH CAROLINA COAST WILL MOVE SLOWLY SOUTH
OVER THE NEXT FEW DAYS. HIGH PRESSURE WILL BUILD INTO THE AREA
TODAY THEN SLIDE OFFSHORE. THE LOW PRESSURE OFF THE SOUTHEAST
COAST WILL MOVE NORTH MID WEEK AND MAY COMBINE WITH A FRONT MOVING
IN FROM THE WEST LATE IN THE WEEK. HIGH PRESSURE WILL BUILD IN
FROM THE NORTHWEST SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
AS OF 950 PM SUNDAY...VERY NICE WEATHER FOR LATE JUNE WITH
SURFACE RIDGE BUILDING DOWN THE MID ATLANTIC TO THE CAROLINAS.
DEWPOINTS ARE GENERALLY IN THE 60S ACROSS THE AREA WITH LIGHT NE/E
WINDS. LOW TEMPERATURES OVERNIGHT SHOULD BE MAINLY IN THE
MID/UPPER 60S WITH PERHAPS SOME LOW 60S AT THE NORMALLY COOLER
SPOTS. EXPECT PATCHY HIGH CLOUDS...MAINLY NEAR THE COAST. NO REAL
CHANGES TO THE CURRENT FORECAST.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
UPPER RIDGE ALONG THE EASTERN SEABOARD REMAINS THE MAJOR PLAYER IN
AREA WEATHER ON MONDAY WITH SFC HIGH PRESSURE TO THE NORTH
GRADUALLY SHIFTING OFFSHORE. SUBSIDENCE AND NIL FORCING WILL AGAIN
SUPPRESS CONVECTION AND LIMIT PRECIP CHANCES SO WILL KEEP THE FCST
DRY. DEW POINTS WILL BEGIN TO RECOVER BUT STILL RELATIVELY
COMFORTABLE FOR THIS TIME OF YEAR WHILE HIGHS REACH NEAR 90
INLAND FROM THE COAST MONDAY. SOME HIGH CLOUDS MAY OVERSPILL THE
UPPER RIDGE AND A FEW SMALL CU MAY DEVELOP IN THE AFTN OTHERWISE A
MOSTLY SUNNY DAY TO BEGIN THE WORK WEEK.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
AS OF 3 PM SUN...SFC HIGH PRESSURE WILL EXTEND OVER THE AREA
MONDAY NIGHT THROUGH WED. UPPER RIDGE WILL CONTINUE TO BUILD OVER
THE AREA TUE AND WED...LIKELY SUPPRESSING MUCH CONVECTIVE
COVERAGE...THOUGH RESULTING IN HOT AND HUMID CONDITIONS ACROSS THE
AREA. LOW LEVEL THICKNESS VALUES AND 850MB TEMPS SUPPORT HIGHS IN
THE MID 80S TO MID 90S. AT THIS TIME WED LOOKS LIKE THE WARMEST
DAY WITH HEAT INDEX VALUES AROUND 100 DEGREES. RIDGE BREAKS DOWN
LATE WEEK AS UPPER TROUGH AND FRONTAL SYSTEM APPROACH FROM THE
WEST.
CONFIDENCE REMAINS LOW LATE WEEK INTO THE EARLY PART OF THE
WEEKEND WITH CONTINUED MODEL DIFFERENCES AND THE POTENTIAL FOR A
STRENGTHENING SFC LOW OFF THE SE COAST. THE ECMWF CONTINUES TO BE
MUCH STRONGER WITH THE LOW THAN GFS...MOVING THE LOW OFF THE NC
COAST FRI/FRI NIGHT...WHILE THE GFS CONTINUES TO FAVOR A MORE
INLAND SOLUTION. CONTINUED TO TREND WITH WPC AND PREVIOUS FORECAST
AT THIS TIME. PLEASE STAY TUNED TO LATEST FORECASTS OVER THE NEXT
SEVERAL DAYS.
FRONTAL BOUNDARY WILL LIKELY COMBINE WITH SFC LOW LATE WEEK...WITH
FRONT LIKELY PUSHING THROUGH THE AREA THIS WEEKEND. COOLER AND
DRIER AIR EXPECTED LATE SAT AND SUN AS HIGH PRESSURE BUILDS IN
FROM THE NW...AND LOW PRESSURE SYSTEM MOVES NNE.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
SHORT TERM /THROUGH 18Z MONDAY/...
AS OF 7 PM SUNDAY...VFR CONDITIONS SHOULD DOMINATE TONIGHT AND
MONDAY. LATEST HRRR GUIDANCE AND LOOK AT THE CONDENSATION PRESSURE
DEFICIT SHOWS MINIMAL CHANCE OF FOG. NUMERICAL GUIDANCE SHOWS A
BRIEF PERIOD OF MVFR VSBY FOG AT THE TAF SITES GIVEN DECOUPLING OF
WIND LATE AND GOOD RADIATIONAL COOLING CONDITIONS. WILL CONTINUE
FORECAST OF MVFR FOG LATE TONIGHT. ANY FOG LIFTS QUICKLY AFTER
SUNRISE MONDAY.
LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 3 PM SUN...PRED VFR CONDITIONS EXPECTED THROUGH THE PERIOD.
ISOLATED AFTERNOON AND EVENING CONVECTION POSSIBLE WED...WITH
BETTER CHANCES THU AND FRI. PATCHY FOG AND STRATUS POSSIBLE EACH
NIGHT/EARLY MORNING WITH MOIST BOUNDARY LAYER.
&&
.MARINE...
SHORT TERM /THROUGH MONDAY/...
AS OF 950 PM SUNDAY...MINIMAL CHANGES TO CURRENT MARINE FORECAST
WITH NE/E WINDS GENERALLY 10 KNOTS OR LESS...EXCEPT OCCASIONAL TO
15 KNOTS AROUND DIAMOND BUOY. WINDS SHOULD BECOME MORE SOUTHEAST ON
MONDAY. SEAS SHOULD CONTINUE IN THE 2 TO 4 FOOT RANGE TONIGHT AND
MONDAY.
LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 3 PM SUN...QUIET AND BENIGN BOATING CONDITIONS FOR THE FIRST
PART OF THE PERIOD. SE FLOW MON NIGHT BECOMING SLY TUE. S/SW FLOW
5-15KT WILL CONTINUE TUE THROUGH WED NIGHT...WITH SEAS GENERALLY
2-4FT. CONFIDENCE REMAINS LOW THU AND FRI WITH CONTINUED MODEL
DIFFERENCES AND THE POTENTIAL FOR A STRENGTHENING SFC LOW OFF THE
SE COAST. THE ECMWF CONTINUES TO BE MUCH STRONGER WITH THE LOW
THAN GFS...MOVING THE LOW OFF THE NC COAST FRI/FRI NIGHT...WHILE
THE GFS CONTINUES TO FAVOR A MORE INLAND SOLUTION. PLEASE STAY
TUNED TO LATEST FORECASTS OVER THE NEXT SEVERAL DAYS.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...BTC
NEAR TERM...CTC
SHORT TERM...BTC
LONG TERM...CQD
AVIATION...CTC/CQD
MARINE...CTC/CQD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
920 PM EDT SUN JUN 29 2014
.SYNOPSIS...AN UPPER LEVEL RIDGE OVER THE REGION WILL WEAKEN BY MID
WEEK AS AN UPPER LEVEL TROUGH AND ATTENDANT COLD FRONT APPROACH FROM
THE NORTHWEST. MEANWHILE...AN AREA OF DISTURBED WEATHER OFFSHORE THE
SOUTHEAST COAST MAY DEVELOP INTO A TROPICAL CYCLONE THAT COULD
AFFECT PORTIONS OF THE SOUTHEAST COAST MID TO LATE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 920 PM SUNDAY...
LATEST REGIONAL RADAR SHOWS THE THIN LINE OF SHOWERS AND A FEW TSTMS
MOVING ACROSS THE FOOTHILLS AND SOON APPROACHING THE WESTERN
PIEDMONT. THESE SHOWERS HAVE BEEN TRENDING DOWNWARD IN COVERAGE AND
INTENSITY...AND EXPECT THIS TREND TO CONTINUE GIVEN THE CURRENT
MESOANALYSIS WHICH SHOWS RELATIVELY DRIER AIR OVER CENTRAL NC.
NEARLY ALL THERMODYNAMIC AND MOISTURE PARAMETERS SUGGEST THAT THESE
SHOWERS WILL DISSIPATE EITHER JUST BEFORE...OR SHORTLY AFTER
REACHING OUR FAR WESTERN ZONES. WOULDN`T BE SURPRISED TO SEE PLACES
LIKE WINSTON-SALEM AND LEXINGTON SEE A VERY BRIEF LIGHT SHOWER
AROUND MIDNIGHT...BUT THAT`S ABOUT AS FAR EAST AS THE SHOWERS WILL
MAKE IT BEFORE COMPLETELY DISSIPATING. THIS SCENARIO IS WELL-
SUPPORTED BY LATEST RUN OF THE HRRR. OTHERWISE FOR THE REST OF THE
OVERNIGHT...LOOK FOR MID AND HIGH CLOUDS CURRENTLY TO OUR WEST TO
SPREAD EAST. LOW TEMPS IN THE MID 60S STILL LOOKS ON-TRACK GIVEN
CURRENT TEMPS/DWPTS AND CLOUDS. ANY FEW SPOTS THAT REMAIN MOSTLY
CLEAR SKIES OVERNIGHT MAY EVEN BE ABLE TO DIP DOWN A LITTLE
COOLER...CLOSER TO 60. OTHER THAN A FEW TWEAKS FOR CURRENT
CONDITIONS...NO MAJOR GRID CHANGES PLANNED FOR THE EVENING UPDATE.
PREVIOUS NEAR TERM DISCUSSION AS OF 250 PM SUNDAY... THE LATEST
SURFACE ANALYSIS IS LITTLE CHANGED FROM EARLIER TODAY... WITH HIGH
PRESSURE OVER CENTRAL NORTH CAROLINA AND A DIFFUSE FRONT OVER THE
WESTERN CAROLINAS...ESSENTIALLY SEPARATING SURFACE DEW POINTS
LARGELY IN THE 50S FROM DEW POINTS WELL INTO THE 60S OR NEAR 70F.
MAIN WEATHER CONCERN THROUGH THE EVENING HOURS IS THE PROGRESS OF A
NARROW BAND OF MID-LEVEL MOISTURE...WITH A WEAK 700MB WAVE AS
ANALYZED BY THE MAJORITY OF NWP ON THE GRADIENT OF HIGHER 850MB
THETA-E AND PRECIPITABLE WATER...MOVING EAST INTO CENTRAL NORTH
CAROLINA. HIGH PRESSURE AND BELOW NORMAL OVERALL MOISTURE TO THE
EAST OF THE WAVE HAS RESULTED IN A STRUGGLE OF THE CLOUDS TO MOVE
MUCH PAST THE WESTERN TWO TIERS OF COUNTIES OR SO...WITH PATCHY RAIN
CONFINED LARGELY TO FORSYTH COUNTY AND INTO WESTERN PERSON COUNTY.
WITH LOW DEW POINTS IN PLACE...MUCH OF ANY PRECIPITATION THIS
EVENING COULD BE SPRINKLES...AND THE LATEST VISIBLE IMAGERY HAS
SHOWN SOME EROSION OF THE WEST END OF THE CLOUD BAND AS THE RAGGED
EAST EDGE OF THE CLOUDS MOVES SLOWLY EAST. THE NAM AND THE GFS
FORECAST THE MID-LEVEL WAVE TO STEADILY MOVE EAST ACROSS CENTRAL
NORTH CAROLINA OVERNIGHT...AND SOME OF THE BUFR SOUNDINGS WOULD
INDICATE A PERIOD OF MOSTLY CLOUDY CONDITIONS ESPECIALLY TOWARD KRDU
AND KRWI OVERNIGHT. GRIDDED GUIDANCE FROM THE GFS WOULD PROVIDE FOR
CONSIDERABLE CLOUD COVER OVERNIGHT...BUT THE LATEST TRENDS AND THE
MOISTURE FIELDS...PARTICULARLY FROM THE LATEST RAP...WOULD SUGGEST
THAT IS TOO PESSIMISTIC. FOR THIS FORECAST...WILL AVERAGE A PARTLY
CLOUDY SKY OVERNIGHT IN CENTRAL NORTH CAROLINA WITH THE LEAST AMOUNT
OF CLOUDS TOWARD KFAY AND KCTZ. PRECIPITABLE WATER VALUES SHOULD
CREEP UP OVERNIGHT AS THE UPPER RIDGE AXIS MOVES VERY SLOWLY EAST...
AND WILL FORECAST LOWS MOSTLY WITH A BLEND OF THE MAV AND MET MOS
GUIDANCE...THOUGH CERTAINLY TOWARD THE WARMER MET NEAR KRWI...MOSTLY
IN THE MID 60S.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 250 PM SUNDAY...
THE NAM AND THE GFS FORECAST PRECIPITABLE WATER VALUES INCREASING BY
AFTERNOON IN CENTRAL NORTH CAROLINA TO VALUES NOW AT OR ABOVE
NORMAL...TO NEARLY TWO INCHES ON THE GFS BY 00Z TUESDAY...AND WHILE
NOT SO HIGH ON THE NAM STILL TO ABOUT 1.8 INCHES BY THE SAME TIME.
AS THE MOISTURE INCREASES...WEAK SURFACE HIGH PRESSURE REMAINS...
LEAVING LITTLE LOW-LEVEL MECHANISMS FOR STRONG LIFT. BOTH THE NAM
AND THE GFS SUGGEST UPPER-LEVEL CONVERGENCE FOR THIS PART OF THE
FORECAST...AND ONLY WEAK 850MB CONVERGENCE MAINLY TOWARD THE WESTERN
PIEDMONT WHERE THE BETTER LIFT...RELATIVE TO THE REST OF CENTRAL
NORTH CAROLINA...IS FORECAST. GFS AND NAM BUFR SOUNDINGS SHOW THAT
ESSENTIALLY THE AIR MASS OVER CENTRAL NORTH CAROLINA IS CAPPED TO
DEEP CONVECTION EXCEPT TOWARD THE TRIAD...WHERE THERE WOULD BE
ENOUGH INSTABILITY IF A STORM COULD DEVELOP OR MOVE INTO THE AREA TO
BE SUSTAINED. MLCAPE IN THE LOWEST KM IS UNDER 1000J/KG AND
DOWNDRAFT CAPE IS WEAK...UNDER 400J/KG...SO CURRENTLY THE CHANCES OF
VIGOROUS CONVECTION APPEARS LOW. LIFTED INDICES MONDAY AFTERNOON ARE
TO -2C ON THE NAM WHICH GENERATES NO QPF AT ALL IN CENTRAL NORTH
CAROLINA...AND TO -4C OR SO ON THE GFS WHICH DOES PROVIDE FOR A
LARGER AREA OF QPF OVER THE WESTERN PIEDMONT MONDAY AFTERNOON WEST
OF U.S. 1...ALTHOUGH WITH LESSER MOS GUIDANCE POPS THAN THE NAM.
SOME OF THE HRRR WRF GUIDANCE WOULD SUGGEST ISOLATED TO WIDELY
SCATTERED SHOWERS AND STORMS POSSIBLE WEST OF U.S. 1 MONDAY
AFTERNOON INTO THE EVENING SO WILL BLEND THE NAM...GFS...AND THE WRF
GUIDANCE AND SHOW THE POTENTIAL FOR MAINLY ISOLATED SHOWERS AND
THUNDERSTORMS IN THAT AREA MONDAY AFTERNOON INTO MONDAY EVENING
BEFORE WANING DIURNALLY. HIGHS MONDAY AROUND 90 ON AVERAGE OVER
CENTRAL NORTH CAROLINA WITH OVERNIGHT LOWS MONDAY NIGHT IN THE UPPER
60S TO NEAR 70...CLOSER TO THE WARMER MOS GUIDANCE DUE TO THE
INCREASINGLY MOIST AIR. -DJF
TUE/TUE NIGHT: THE UPPER LEVEL RIDGE CURRENTLY IN PLACE OVER THE
SOUTHEASTERN CONUS WILL BEGIN TO FLATTEN TUE/TUE NIGHT AS AN UPPER
LEVEL LOW (CURRENTLY IN MANITOBA) TRACKS ESE TO THE UPPER GREAT
LAKES...RESULTING IN HEIGHT FALLS AND STRENGTHENING SOUTHWEST FLOW
ALOFT ACROSS THE NORTHERN MID-ATLANTIC...THOUGH THE HEIGHT GRADIENT
WILL CHANGE LITTLE FURTHER SOUTH IN THE CAROLINAS. A PRE-FRONTAL
TROUGH IN ADVANCE OF A COLD FRONT ATTENDANT THE AFOREMENTIONED UPPER
LEVEL WAVE WILL PROGRESS INTO THE MID-ATLANTIC TUE AFT/EVE. FORCING
FOR ASCENT WILL BE CONFINED TO WEAK/SHALLOW CONVERGENCE IN VICINITY
OF THE PIEDMONT TROUGH AND ALONG THE SEABREEZE...THE LATTER OF WHICH
COULD PENETRATE WELL INLAND VIA ONSHORE FLOW (S/SE). MID-LEVEL LAPSE
RATES ARE PROGGED TO STEEPEN FROM THE WEST TUE AFT/EVE AS A MODIFIED
EML ADVECTS INTO THE SOUTHERN APPALACHIANS. THOUGH THIS FEATURE WILL
RESULT IN ENHANCED DESTABILIZATION ACROSS THE WESTERN PIEDMONT (UP
TO 2000 J/KG MLCAPE)...IT WILL ALSO RESULT IN AN ENHANCED MID-LEVEL
CAP AND /DRY MID-LEVEL AIRMASS/ THAT COULD PRECLUDE DEVELOPMENT IN
THE PRESENCE OF SUCH WEAK FORCING. HOWEVER...GIVEN A POTENTIAL FOR
MOUNTAIN CONVECTION TO DRIFT EASTWARD IN AN ENV. WHICH WOULD FAVOR
STRONG COLD POOLS...A SLIGHT CHANCE OF CONVECTION APPEARS WARRANTED
IN THE FAR WESTERN PIEDMONT. WILL ALSO INDICATE A SLIGHT CHANCE OF
CONVECTION IN THE SOUTHEAST COASTAL PLAIN IN ASSOC/W ONSHORE FLOW IN
THE PRESENCE OF A WEAKER MID-LEVEL CAP (ALBEIT WITH WEAKER
INSTABILITY). EXPECT HIGHS TUE IN THE 90-95F RANGE...WARMEST IN THE
SANDHILLS. LOWS TUE NIGHT WILL BE MUGGY GIVEN ONSHORE FLOW...IN THE
LOWER TO MID 70S. -VINCENT
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY NIGHT/...
AS OF 325 PM SUNDAY...
WEDNESDAY THROUGH FRIDAY: EXPECT ABOVE NORMAL HIGHS AND
CLIMATOLOGICAL CHANCES FOR CONVECTION ON WED AS SOUTHWEST FLOW ALOFT
ADVECTS A WARMER MID-LEVEL AIRMASS INTO THE REGION...FOLLOWED BY
NEAR NORMAL HIGHS AND ABOVE NORMAL CHANCES FOR CONVECTION THU/FRI IN
ASSOC/W INCREASINGLY CYCLONIC FLOW ALOFT OVER THE MID-ATLANTIC/
CAROLINAS AND LOW-LEVEL CONVERGENCE ASSOC/W A COLD FRONT ATTENDANT
AN UPPER LEVEL TROUGH APPROACHING FROM THE WEST. HOWEVER...FORECAST
UNCERTAINTY HAS INCREASED ACROSS THE SOUTHEAST CONUS IN ASSOC/W THE
POTENTIAL FOR HOMEGROWN TROPICAL CYCLONE DEVELOPMENT ALONG THE
SOUTHEAST COAST WED-FRI. IF A TROPICAL CYCLONE DEVELOPS AND TRACKS
ALONG/JUST OFFSHORE THE CAROLINA COAST...THERE ARE TWO PRIMARY
SCENARIOS: 1) IF THE TRACK IS FURTHER OFFSHORE AND/OR THE
APPROACHING TROUGH IS SLOWER...PRECIP CHANCES COULD BE LOWER THAN
OTHERWISE EXPECTED IN THE COASTAL PLAIN IN ASSOC/W SUBSIDENCE AND A
DRY MID-LEVEL AIRMASS ON THE WESTERN PERIPHERY OF THE SYSTEM...OR 2)
IF THE TRACK IS CLOSER TO THE COAST (OR INLAND) AND THE TROUGH
APPROACHES AS PROGGED BY 12Z GUIDANCE...THEN THE ENVIRONMENT WOULD
FAVOR A `LEFT OF TRACK` SCENARIO WITH POTENTIALLY SIGNIFICANT
PRECIPITATION ACROSS PORTIONS OF EASTERN NC. GIVEN ABOVE NORMAL
UNCERTAINTY...WILL MAKE FEW CHANGES TO THE FORECAST FOR THIS PERIOD.
SATURDAY THROUGH MONDAY: THE PROGRESSIVE UPPER LEVEL TROUGH MOVING
EAST INTO THE REGION WED-FRI IS EXPECTED TO TRACK OFFSHORE THE MID-
ATLANTIC COAST EARLY SATURDAY...STEERING THE POTENTIAL TROPICAL
CYCLONE OFFSHORE WITH EVENTUAL INTERACTION /EXTRATROPICAL
TRANSITION/ OCCURRING WELL NORTHEAST OF CENTRAL NC OFF THE MID-
ATLANTIC COAST. WITH SYNOPTIC SUBSIDENCE AND A DRIER /MORE STABLE/
AIRMASS IN PLACE IN THE WAKE OF THE COLD FRONTAL PASSAGE...EXPECT
NEAR NORMAL TEMPS AND DRY CONDITIONS THROUGH THE WEEKEND. -VINCENT
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
AS OF 750 PM SUNDAY...
VFR CONDITIONS ARE EXPECTED TO PERSIST THROUGH THE CURRENT TAF
PERIOD AS HIGH PRESSURE...BOTH AT THE SURFACE AND ALOFT...DOMINATE
THE WEATHER ACROSS CENTRAL NC. PERIODS OF MID/HIGH CLOUDS WILL BE
POSSIBLE...ESPECIALLY DURING THE DAY ON MONDAY. WINDS WILL GENERALLY
BE LIGHT AND VARIABLE...EVENTUALLY BECOMING S/SW ON MONDAY AS THE
SURFACE HIGH STARTS TO SHIFT OFFSHORE. ONLY AN ISOLATED DIURNAL
SHOWER/STORM OR TWO IS EXPECTED FOR MONDAY...MAINLY ACROSS THE WEST
(KINT/KGSO).
OUTLOOK...WITH HIGH PRESSURE IN CONTROL BOTH AT THE SURFACE AND
ALOFT...TYPICAL DIURNAL SUMMERTIME CONVECTION IS EXPECTED ONCE AGAIN
ON TUESDAY. THEN FOR THE REMAINDER OF THE WEEK...THE HIGH PRESSURE
SYSTEM IS EXPECTED TO WEAKEN AS AN UPPER LEVEL TROUGH/SURFACE FRONT
APPROACHES THE REGION...RESULTING IN A BETTER CHANCE FOR AFTERNOON
SHOWERS AND THUNDERSTORMS. OTHERWISE...SHOULD SEE A BRIEF PERIOD OF
EARLY MORNING FOG/LOW STRATUS...ESPECIALLY FOR THE LATTER HALF OF
THE WEEK.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...NP/DJF
SHORT TERM...DJF/VINCENT
LONG TERM...VINCENT
AVIATION...KRD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
753 PM EDT SUN JUN 29 2014
.SYNOPSIS...AN UPPER LEVEL RIDGE OVER THE REGION WILL WEAKEN BY MID
WEEK AS AN UPPER LEVEL TROUGH AND ATTENDANT COLD FRONT APPROACH FROM
THE NORTHWEST. MEANWHILE...AN AREA OF DISTURBED WEATHER OFFSHORE THE
SOUTHEAST COAST MAY DEVELOP INTO A TROPICAL CYCLONE THAT COULD
AFFECT PORTIONS OF THE SOUTHEAST COAST MID TO LATE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 250 PM SUNDAY...
THE LATEST SURFACE ANALYSIS IS LITTLE CHANGED FROM EARLIER TODAY...
WITH HIGH PRESSURE OVER CENTRAL NORTH CAROLINA AND A DIFFUSE FRONT
OVER THE WESTERN CAROLINAS...ESSENTIALLY SEPARATING SURFACE DEW
POINTS LARGELY IN THE 50S FROM DEW POINTS WELL INTO THE 60S OR NEAR
70F. MAIN WEATHER CONCERN THROUGH THE EVENING HOURS IS THE PROGRESS
OF A NARROW BAND OF MID-LEVEL MOISTURE...WITH A WEAK 700MB WAVE AS
ANALYZED BY THE MAJORITY OF NWP ON THE GRADIENT OF HIGHER 850MB
THETA-E AND PRECIPITABLE WATER...MOVING EAST INTO CENTRAL NORTH
CAROLINA. HIGH PRESSURE AND BELOW NORMAL OVERALL MOISTURE TO THE
EAST OF THE WAVE HAS RESULTED IN A STRUGGLE OF THE CLOUDS TO MOVE
MUCH PAST THE WESTERN TWO TIERS OF COUNTIES OR SO...WITH PATCHY RAIN
CONFINED LARGELY TO FORSYTH COUNTY AND INTO WESTERN PERSON COUNTY.
WITH LOW DEW POINTS IN PLACE...MUCH OF ANY PRECIPITATION THIS
EVENING COULD BE SPRINKLES...AND THE LATEST VISIBLE IMAGERY HAS
SHOWN SOME EROSION OF THE WEST END OF THE CLOUD BAND AS THE RAGGED
EAST EDGE OF THE CLOUDS MOVES SLOWLY EAST. THE NAM AND THE GFS
FORECAST THE MID-LEVEL WAVE TO STEADILY MOVE EAST ACROSS CENTRAL
NORTH CAROLINA OVERNIGHT...AND SOME OF THE BUFR SOUNDINGS WOULD
INDICATE A PERIOD OF MOSTLY CLOUDY CONDITIONS ESPECIALLY TOWARD KRDU
AND KRWI OVERNIGHT. GRIDDED GUIDANCE FROM THE GFS WOULD PROVIDE FOR
CONSIDERABLE CLOUD COVER OVERNIGHT...BUT THE LATEST TRENDS AND THE
MOISTURE FIELDS...PARTICULARLY FROM THE LATEST RAP...WOULD SUGGEST
THAT IS TOO PESSIMISTIC. FOR THIS FORECAST...WILL AVERAGE A PARTLY
CLOUDY SKY OVERNIGHT IN CENTRAL NORTH CAROLINA WITH THE LEAST AMOUNT
OF CLOUDS TOWARD KFAY AND KCTZ. PRECIPITABLE WATER VALUES SHOULD
CREEP UP OVERNIGHT AS THE UPPER RIDGE AXIS MOVES VERY SLOWLY EAST...
AND WILL FORECAST LOWS MOSTLY WITH A BLEND OF THE MAV AND MET MOS
GUIDANCE...THOUGH CERTAINLY TOWARD THE WARMER MET NEAR KRWI...MOSTLY
IN THE MID 60S.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 250 PM SUNDAY...
THE NAM AND THE GFS FORECAST PRECIPITABLE WATER VALUES INCREASING BY
AFTERNOON IN CENTRAL NORTH CAROLINA TO VALUES NOW AT OR ABOVE
NORMAL...TO NEARLY TWO INCHES ON THE GFS BY 00Z TUESDAY...AND WHILE
NOT SO HIGH ON THE NAM STILL TO ABOUT 1.8 INCHES BY THE SAME TIME.
AS THE MOISTURE INCREASES...WEAK SURFACE HIGH PRESSURE REMAINS...
LEAVING LITTLE LOW-LEVEL MECHANISMS FOR STRONG LIFT. BOTH THE NAM
AND THE GFS SUGGEST UPPER-LEVEL CONVERGENCE FOR THIS PART OF THE
FORECAST...AND ONLY WEAK 850MB CONVERGENCE MAINLY TOWARD THE WESTERN
PIEDMONT WHERE THE BETTER LIFT...RELATIVE TO THE REST OF CENTRAL
NORTH CAROLINA...IS FORECAST. GFS AND NAM BUFR SOUNDINGS SHOW THAT
ESSENTIALLY THE AIR MASS OVER CENTRAL NORTH CAROLINA IS CAPPED TO
DEEP CONVECTION EXCEPT TOWARD THE TRIAD...WHERE THERE WOULD BE
ENOUGH INSTABILITY IF A STORM COULD DEVELOP OR MOVE INTO THE AREA TO
BE SUSTAINED. MLCAPE IN THE LOWEST KM IS UNDER 1000J/KG AND
DOWNDRAFT CAPE IS WEAK...UNDER 400J/KG...SO CURRENTLY THE CHANCES OF
VIGOROUS CONVECTION APPEARS LOW. LIFTED INDICES MONDAY AFTERNOON ARE
TO -2C ON THE NAM WHICH GENERATES NO QPF AT ALL IN CENTRAL NORTH
CAROLINA...AND TO -4C OR SO ON THE GFS WHICH DOES PROVIDE FOR A
LARGER AREA OF QPF OVER THE WESTERN PIEDMONT MONDAY AFTERNOON WEST
OF U.S. 1...ALTHOUGH WITH LESSER MOS GUIDANCE POPS THAN THE NAM.
SOME OF THE HRRR WRF GUIDANCE WOULD SUGGEST ISOLATED TO WIDELY
SCATTERED SHOWERS AND STORMS POSSIBLE WEST OF U.S. 1 MONDAY
AFTERNOON INTO THE EVENING SO WILL BLEND THE NAM...GFS...AND THE WRF
GUIDANCE AND SHOW THE POTENTIAL FOR MAINLY ISOLATED SHOWERS AND
THUNDERSTORMS IN THAT AREA MONDAY AFTERNOON INTO MONDAY EVENING
BEFORE WANING DIURNALLY. HIGHS MONDAY AROUND 90 ON AVERAGE OVER
CENTRAL NORTH CAROLINA WITH OVERNIGHT LOWS MONDAY NIGHT IN THE UPPER
60S TO NEAR 70...CLOSER TO THE WARMER MOS GUIDANCE DUE TO THE
INCREASINGLY MOIST AIR. -DJF
TUE/TUE NIGHT: THE UPPER LEVEL RIDGE CURRENTLY IN PLACE OVER THE
SOUTHEASTERN CONUS WILL BEGIN TO FLATTEN TUE/TUE NIGHT AS AN UPPER
LEVEL LOW (CURRENTLY IN MANITOBA) TRACKS ESE TO THE UPPER GREAT
LAKES...RESULTING IN HEIGHT FALLS AND STRENGTHENING SOUTHWEST FLOW
ALOFT ACROSS THE NORTHERN MID-ATLANTIC...THOUGH THE HEIGHT GRADIENT
WILL CHANGE LITTLE FURTHER SOUTH IN THE CAROLINAS. A PRE-FRONTAL
TROUGH IN ADVANCE OF A COLD FRONT ATTENDANT THE AFOREMENTIONED UPPER
LEVEL WAVE WILL PROGRESS INTO THE MID-ATLANTIC TUE AFT/EVE. FORCING
FOR ASCENT WILL BE CONFINED TO WEAK/SHALLOW CONVERGENCE IN VICINITY
OF THE PIEDMONT TROUGH AND ALONG THE SEABREEZE...THE LATTER OF WHICH
COULD PENETRATE WELL INLAND VIA ONSHORE FLOW (S/SE). MID-LEVEL LAPSE
RATES ARE PROGGED TO STEEPEN FROM THE WEST TUE AFT/EVE AS A MODIFIED
EML ADVECTS INTO THE SOUTHERN APPALACHIANS. THOUGH THIS FEATURE WILL
RESULT IN ENHANCED DESTABILIZATION ACROSS THE WESTERN PIEDMONT (UP
TO 2000 J/KG MLCAPE)...IT WILL ALSO RESULT IN AN ENHANCED MID-LEVEL
CAP AND /DRY MID-LEVEL AIRMASS/ THAT COULD PRECLUDE DEVELOPMENT IN
THE PRESENCE OF SUCH WEAK FORCING. HOWEVER...GIVEN A POTENTIAL FOR
MOUNTAIN CONVECTION TO DRIFT EASTWARD IN AN ENV. WHICH WOULD FAVOR
STRONG COLD POOLS...A SLIGHT CHANCE OF CONVECTION APPEARS WARRANTED
IN THE FAR WESTERN PIEDMONT. WILL ALSO INDICATE A SLIGHT CHANCE OF
CONVECTION IN THE SOUTHEAST COASTAL PLAIN IN ASSOC/W ONSHORE FLOW IN
THE PRESENCE OF A WEAKER MID-LEVEL CAP (ALBEIT WITH WEAKER
INSTABILITY). EXPECT HIGHS TUE IN THE 90-95F RANGE...WARMEST IN THE
SANDHILLS. LOWS TUE NIGHT WILL BE MUGGY GIVEN ONSHORE FLOW...IN THE
LOWER TO MID 70S. -VINCENT
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY NIGHT/...
AS OF 325 PM SUNDAY...
WEDNESDAY THROUGH FRIDAY: EXPECT ABOVE NORMAL HIGHS AND
CLIMATOLOGICAL CHANCES FOR CONVECTION ON WED AS SOUTHWEST FLOW ALOFT
ADVECTS A WARMER MID-LEVEL AIRMASS INTO THE REGION...FOLLOWED BY
NEAR NORMAL HIGHS AND ABOVE NORMAL CHANCES FOR CONVECTION THU/FRI IN
ASSOC/W INCREASINGLY CYCLONIC FLOW ALOFT OVER THE MID-ATLANTIC/
CAROLINAS AND LOW-LEVEL CONVERGENCE ASSOC/W A COLD FRONT ATTENDANT
AN UPPER LEVEL TROUGH APPROACHING FROM THE WEST. HOWEVER...FORECAST
UNCERTAINTY HAS INCREASED ACROSS THE SOUTHEAST CONUS IN ASSOC/W THE
POTENTIAL FOR HOMEGROWN TROPICAL CYCLONE DEVELOPMENT ALONG THE
SOUTHEAST COAST WED-FRI. IF A TROPICAL CYCLONE DEVELOPS AND TRACKS
ALONG/JUST OFFSHORE THE CAROLINA COAST...THERE ARE TWO PRIMARY
SCENARIOS: 1) IF THE TRACK IS FURTHER OFFSHORE AND/OR THE
APPROACHING TROUGH IS SLOWER...PRECIP CHANCES COULD BE LOWER THAN
OTHERWISE EXPECTED IN THE COASTAL PLAIN IN ASSOC/W SUBSIDENCE AND A
DRY MID-LEVEL AIRMASS ON THE WESTERN PERIPHERY OF THE SYSTEM...OR 2)
IF THE TRACK IS CLOSER TO THE COAST (OR INLAND) AND THE TROUGH
APPROACHES AS PROGGED BY 12Z GUIDANCE...THEN THE ENVIRONMENT WOULD
FAVOR A `LEFT OF TRACK` SCENARIO WITH POTENTIALLY SIGNIFICANT
PRECIPITATION ACROSS PORTIONS OF EASTERN NC. GIVEN ABOVE NORMAL
UNCERTAINTY...WILL MAKE FEW CHANGES TO THE FORECAST FOR THIS PERIOD.
SATURDAY THROUGH MONDAY: THE PROGRESSIVE UPPER LEVEL TROUGH MOVING
EAST INTO THE REGION WED-FRI IS EXPECTED TO TRACK OFFSHORE THE MID-
ATLANTIC COAST EARLY SATURDAY...STEERING THE POTENTIAL TROPICAL
CYCLONE OFFSHORE WITH EVENTUAL INTERACTION /EXTRATROPICAL
TRANSITION/ OCCURRING WELL NORTHEAST OF CENTRAL NC OFF THE MID-
ATLANTIC COAST. WITH SYNOPTIC SUBSIDENCE AND A DRIER /MORE STABLE/
AIRMASS IN PLACE IN THE WAKE OF THE COLD FRONTAL PASSAGE...EXPECT
NEAR NORMAL TEMPS AND DRY CONDITIONS THROUGH THE WEEKEND. -VINCENT
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
AS OF 750 PM SUNDAY...
VFR CONDITIONS ARE EXPECTED TO PERSIST THROUGH THE CURRENT TAF
PERIOD AS HIGH PRESSURE...BOTH AT THE SURFACE AND ALOFT...DOMINATE
THE WEATHER ACROSS CENTRAL NC. PERIODS OF MID/HIGH CLOUDS WILL BE
POSSIBLE...ESPECIALLY DURING THE DAY ON MONDAY. WINDS WILL GENERALLY
BE LIGHT AND VARIABLE...EVENTUALLY BECOMING S/SW ON MONDAY AS THE
SURFACE HIGH STARTS TO SHIFT OFFSHORE. ONLY AN ISOLATED DIURNAL
SHOWER/STORM OR TWO IS EXPECTED FOR MONDAY...MAINLY ACROSS THE WEST
(KINT/KGSO).
OUTLOOK...WITH HIGH PRESSURE IN CONTROL BOTH AT THE SURFACE AND
ALOFT...TYPICAL DIURNAL SUMMERTIME CONVECTION IS EXPECTED ONCE AGAIN
ON TUESDAY. THEN FOR THE REMAINDER OF THE WEEK...THE HIGH PRESSURE
SYSTEM IS EXPECTED TO WEAKEN AS AN UPPER LEVEL TROUGH/SURFACE FRONT
APPROACHES THE REGION...RESULTING IN A BETTER CHANCE FOR AFTERNOON
SHOWERS AND THUNDERSTORMS. OTHERWISE...SHOULD SEE A BRIEF PERIOD OF
EARLY MORNING FOG/LOW STRATUS...ESPECIALLY FOR THE LATTER HALF OF
THE WEEK.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...DJF
SHORT TERM...DJF/VINCENT
LONG TERM...VINCENT
AVIATION...KRD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
731 PM EDT SUN JUN 29 2014
.SYNOPSIS...
HIGH PRESSURE WILL MOVE OFF THE MID-ATLANTIC COAST THROUGH THE
MIDDLE OF THE WEEK BRINGING A SLOW WARMING TREND. AN AREA OF
TROPICAL LOW PRESSURE DEVELOPING OFF THE FLORIDA COAST MAY LIFT TO
THE NORTH LATE IN THE WEEK BRINGING INCREASING RAIN CHANCES. A COLD
FRONT WILL STALL AS IT APPROACHES THE AREA LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
AS OF 730 PM SUNDAY...SURPRISINGLY MILD TEMPERATURES ARE EXPECTED
TONIGHT AS 1023 MB HIGH PRESSURE OFF THE MID-ATLANTIC COAST EXTENDS
A RIDGE AXIS ACROSS THE CAROLINAS. OUR FORECAST LOWS ARE IN THE MID
TO UPPER 60S AWAY FROM THE BEACHES. AT WILMINGTON OUR FORECAST LOW
(67 DEGREES) IS IN THE LOWEST 17 PERCENTILE FOR THIS DATE AND 5
DEGREES BELOW NORMAL.
DAYTIME CUMULUS WERE LIMITED TO THE VICINITY OF THE SEABREEZE
BOUNDARY THIS EVENING...MAINLY ACROSS SOUTH CAROLINA WHERE DEWPOINTS
WERE HIGHEST. DRY AIR ASSOCIATED WITH SUBSIDENCE WITHIN THE HIGH
PRESSURE TO OUR NORTH MIXED DEWPOINTS DOWN INTO THE UPPER 50S ACROSS
MUCH OF NORTH CAROLINA INTO INTERIOR NORTHEASTERN SOUTH CAROLINA.
CLEAR SKIES SHOULD PREVAIL TONIGHT WITH PRETTY DECENT RADIATIONAL
COOLING CONSIDERING THE AIRMASS AND TIME OF YEAR. FOG POTENTIAL IS
QUITE LOW OVERALL...BUT THE PEE DEE REGION OF SOUTH CAROLINA AND
ALONG THE SANTEE RIVER PROBABLY HAVE THE HIGHEST POTENTIAL WITH
FORECAST SOUNDINGS FROM THE NAM AND RUC SHOWING SUFFICIENT MOISTURE
PRESENT THROUGH 800-1000 FEET AGL WITH DRYING ALOFT. THE GFS
SOUNDINGS ARE DRIER IN THE LOW-LEVELS WHICH WOULD PRECLUDE FOG.
OUR INCREASINGLY TROPICAL LOW EAST OF FLORIDA IS NOW ALMOST 400
MILES SOUTH OF CAPE FEAR AND SHOULD STALL OVER THE NEXT 12-24 HOURS.
THE OUTERMOST CLOUD BANDS ASSOCIATED WITH THIS FEATURE WILL REMAIN
TO OUR SOUTH TONIGHT WITH NO IMPACTS LOCALLY.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
AS OF 300 PM SUNDAY...SEASONABLE AND QUIET WEATHER FOR THE SHORT
TERM AS THE CALENDAR TICKS INTO JULY. THE SENSIBLE WEATHER WILL BE
CONTROLLED BY HIGH PRESSURE DRIFTING OFF THE MID-ATLANTIC
COAST...AND A MID-LEVEL RIDGE BLOSSOMING FROM THE GULF COAST. ON
MONDAY...MID-LEVEL RIDGE AXIS WILL BE ALIGNED NEARLY
OVERHEAD...SWEEPING OFF TO THE EAST ON TUESDAY. ALTHOUGH THE RIDGE
MOVES EAST ON TUESDAY...THICKNESSES WILL ACTUALLY BE A BIT HIGHER
THAN WHAT IS EXPECTED ON MONDAY. THIS IS IMPORTANT BECAUSE ALTHOUGH
COLUMN MOISTURE INCREASES FROM MONDAY TO TUESDAY...INCREASED
SUBSIDENCE WILL SOMEWHAT OFFSET THE CONVECTIVE POTENTIAL TUESDAY.
STILL...ISOLATED TSTMS WILL BE POSSIBLE TUESDAY...WHILE MONDAY IS
EXPECTED TO REMAIN DRY. TEMPS WILL SLOWLY CLIMB EARLY WEEK...WITH
HIGHS AROUND 90 EXPECTED MONDAY...LOW 90S ON TUESDAY. LOWS MONDAY
NIGHT WILL DROP TO AROUND 70 AWAY FROM THE BEACHES...BUT ONLY INTO
THE LOW/MID 70S TUESDAY NIGHT AS SOUTHERLY RETURN FLOW DEVELOPS
AROUND THE OFFSHORE HIGH PRESSURE.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 300 PM SUNDAY...H5 RIDGE PATTERN ACROSS THE SOUTHEAST WILL
BREAK DOWN DURING THE EXTENDED AS A SHORT WAVE TROUGH SHIFTS EAST
OF THE MID-WEST AND INTO NEW ENGLAND BY THE END OF THE WEEK. OTHER
THAN SOME TYPICAL SUMMERTIME DIURNAL CONVECTION ALL EYES WILL BE
ON THE POTENTIAL DEVELOPMENT OF A TROPICAL SYSTEM OFF THE
SOUTHEAST UNITED STATES COAST. THERE IS NO CONSISTENCY EVIDENT IN
THE MODELS AT THIS TIME WITH THE NAM FAIRLY AGGRESSIVE AND ECMWF
TRACKING THE STORM OFF THE NC COAST FRIDAY. TOO MANY VARIABLES AND
INCONSISTENCIES EXIST AT THIS TIME...THUS LOW CONFIDENCE FORECAST
CONTINUES IN THE EXTENDED. MAX/MIN TEMPERATURES THROUGH THE PERIOD
WILL BE AT OR JUST ABOVE NORMAL WED/THU...WHILE THE GFS IS
POSSIBLY A CATEGORY TOO HIGH FOR MAX TEMPS FRI AND SAT.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
AS OF 00Z...VFR CONDITIONS EXPECTED AT ALL TAF SITES OVERVIEW.
WILL MENTION JUST A TEMPO AT FLO AFTER 08Z FOR MVFR IN BR AS MODEL
SOUNDING DOES SHOW SOME LOW LEVEL MOISTURE IN THE LOWER PORTION OF
THE COLUMN SO WILL JUST MENTION TEMPO TO COVER. OTHERWISE MODELS ARE
SOMEWHAT DRIER IN THE LOW LEVEL FOR THE OVERNIGHT PERIOD. LATEST SAT
IR DOES SHOW CIRRUS DEBRIS CLOUDS WORKING EWD AND THIS WOULD IMPACT
THE REGION OVERNIGHT IN THE FORM OF HIGH CLOUDS WHICH WILL BECOME
SCATTERED TO BROKEN OVER THE TERMINALS OVERNIGHT INTO MONDAY. WINDS
WILL SLACKEN OFF OVERNIGHT TO LIGHT AND VARIABLE AND BECOME MORE E
TO NE THROUGHOUT THE DAY MONDAY AND VEERING TO THE SE ACROSS THE
MYRTLES DURING THE AFTERNOON AS THE SEA BREEZES MOVES ACROSS.
EXTENDED OUTLOOK...AFTERNOON AND EVENING SHOWERS EXPECTED THROUGH
THE PERIOD POSSIBLY CREATING PERIODS OF MVFR/IFR. OTHERWISE EXPECT
VFR. SOME UNCERTAINTY WITH POSSIBLE TROPICAL SYSTEM INTERACTION
WEDNESDAY THROUGH FRIDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 730 PM SUNDAY...LOW PRESSURE HAS DRIFTED TO A POSITION ABOUT
400 MILES SOUTH OF CAPE FEAR THIS EVENING. THIS HAS MADE WAY FOR
1023 MB HIGH PRESSURE OFF THE MID-ATLANTIC COAST TO BUILD ACROSS THE
INTERIOR CAROLINAS. EAST TO NORTHEAST WINDS BETWEEN THIS HIGH AND
THE LOW EAST OF FLORIDA WILL CONTINUE THROUGH THE NIGHT...WITH
GRADUALLY DIMINISHING WIND SPEEDS EXPECTED AS THE PRESSURE GRADIENT
WEAKENS. THE LONG ONSHORE FLOW HAS BUILT SEAS TO AS HIGH AS 4 FEET
WITHIN 20 MILES OF SHORE...ESPECIALLY EAST OF CAPE FEAR. SEAS
CURRENTLY CONSIST OF A 5-SECOND NORTHEAST WIND WAVE PLUS A 9-SECOND
SOUTHEAST SWELL.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 300 PM SUNDAY...PRETTY QUIET MARINE CONDITIONS DURING THE
SHORT TERM...EVEN AS WINDS FLUCTUATE THROUGH MANY COMPASS
DIRECTIONS. HIGH PRESSURE MOVING OFF THE MID-ATLANTIC COAST DRIVES
NE WINDS AROUND 10 KTS ON MONDAY...BUT AS THIS HIGH PUSHES OFFSHORE
THE GRADIENT WILL WEAKEN...AND WINDS WILL BECOME VARIABLE UNTIL
EVENTUALLY BECOMING SW AROUND 10 KTS LATE IN THE PERIOD. SEAS WILL
BE DRIVEN BY A RESIDUAL GROUND SWELL AND A 5 SEC WIND
CHOP...CREATING 2-3 FT SEAS BOTH DAYS.
LONG TERM /WEDNESDAY THROUGH FRIDAY/...
AS OF 300 PM SUNDAY...SOUTHERLY FLOW IS EXPECTED TO PREVAIL
WEDNESDAY INTO WEDNESDAY NIGHT...WITH BACKING TO THE SOUTHEAST AND
INCREASING SPEEDS DURING THURSDAY. BIG QUESTION MARKS REMAIN
THEREAFTER DEPENDING ON THE EVOLUTION OF THE DISTURBED WEATHER OFF
THE GA/FL COASTS. HAVE NUDGED SEAS UP A FOOT FROM THE PREVIOUS
FORECAST AS THE FETCH WILL LIKELY DIRECT MORE ENERGETIC WAVES
TOWARD THE COAST. SMALL CRAFT CONDITIONS ARE POSSIBLE BY THE END
OF THE WEEK...AGAIN ALL DEPENDING ON WHAT HAPPENS WITH THE
AFOREMENTIONED AREA OF DISTURBED WEATHER.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...JDW
NEAR TERM...TRA
SHORT TERM...JDW
LONG TERM...SRP
AVIATION...MAC
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
705 PM EDT SUN JUN 29 2014
.SYNOPSIS...
LOW PRESSURE OFF THE SOUTH CAROLINA COAST WILL MOVE SLOWLY SOUTH
OVER THE NEXT FEW DAYS. HIGH PRESSURE WILL BUILD INTO THE AREA
TODAY THEN SLIDE OFFSHORE. THE LOW PRESSURE OFF THE SOUTHEAST
COAST WILL MOVE NORTH MID WEEK AND MAY COMBINE WITH A FRONT MOVING
IN FROM THE WEST LATE IN THE WEEK. HIGH PRESSURE WILL BUILD IN
FROM THE NORTHWEST SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
VERY NICE WEATHER FOR LATE JUNE WITH SURFACE RIDGE BUILDING DOWN
THE MID ATLANTIC TO THE CAROLINAS. DEWPOINTS ARE GENERALLY IN THE
60S ACROSS THE AREA WITH LIGHT NE/E WINDS. LOW TEMPERATURES WILL
ONCE AGAIN DROP INTO THE 60S OVER MOST ALL OF THE AREA TONIGHT
WITH SOME PATCHY HIGH CLOUDS...MAINLY NEAR THE COAST. NO REAL
CHANGES TO THE CURRENT FORECAST.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
UPPER RIDGE ALONG THE EASTERN SEABOARD REMAINS THE MAJOR PLAYER IN
AREA WEATHER ON MONDAY WITH SFC HIGH PRESSURE TO THE NORTH
GRADUALLY SHIFTING OFFSHORE. SUBSIDENCE AND NIL FORCING WILL AGAIN
SUPPRESS CONVECTION AND LIMIT PRECIP CHANCES SO WILL KEEP THE FCST
DRY. DEW POINTS WILL BEGIN TO RECOVER BUT STILL RELATIVELY
COMFORTABLE FOR THIS TIME OF YEAR WHILE HIGHS REACH NEAR 90
INLAND FROM THE COAST MONDAY. SOME HIGH CLOUDS MAY OVERSPILL THE
UPPER RIDGE AND A FEW SMALL CU MAY DEVELOP IN THE AFTN OTHERWISE A
MOSTLY SUNNY DAY TO BEGIN THE WORK WEEK.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
AS OF 3 PM SUN...SFC HIGH PRESSURE WILL EXTEND OVER THE AREA
MONDAY NIGHT THROUGH WED. UPPER RIDGE WILL CONTINUE TO BUILD OVER
THE AREA TUE AND WED...LIKELY SUPPRESSING MUCH CONVECTIVE
COVERAGE...THOUGH RESULTING IN HOT AND HUMID CONDITIONS ACROSS THE
AREA. LOW LEVEL THICKNESS VALUES AND 850MB TEMPS SUPPORT HIGHS IN
THE MID 80S TO MID 90S. AT THIS TIME WED LOOKS LIKE THE WARMEST
DAY WITH HEAT INDEX VALUES AROUND 100 DEGREES. RIDGE BREAKS DOWN
LATE WEEK AS UPPER TROUGH AND FRONTAL SYSTEM APPROACH FROM THE
WEST.
CONFIDENCE REMAINS LOW LATE WEEK INTO THE EARLY PART OF THE
WEEKEND WITH CONTINUED MODEL DIFFERENCES AND THE POTENTIAL FOR A
STRENGTHENING SFC LOW OFF THE SE COAST. THE ECMWF CONTINUES TO BE
MUCH STRONGER WITH THE LOW THAN GFS...MOVING THE LOW OFF THE NC
COAST FRI/FRI NIGHT...WHILE THE GFS CONTINUES TO FAVOR A MORE
INLAND SOLUTION. CONTINUED TO TREND WITH WPC AND PREVIOUS FORECAST
AT THIS TIME. PLEASE STAY TUNED TO LATEST FORECASTS OVER THE NEXT
SEVERAL DAYS.
FRONTAL BOUNDARY WILL LIKELY COMBINE WITH SFC LOW LATE WEEK...WITH
FRONT LIKELY PUSHING THROUGH THE AREA THIS WEEKEND. COOLER AND
DRIER AIR EXPECTED LATE SAT AND SUN AS HIGH PRESSURE BUILDS IN
FROM THE NW...AND LOW PRESSURE SYSTEM MOVES NNE.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
SHORT TERM /THROUGH 18Z MONDAY/...
AS OF 7 PM SUNDAY...VFR CONDITIONS SHOULD DOMINATE TONIGHT AND
MONDAY. LATEST HRRR GUIDANCE AND LOOK AT THE CONDENSATION PRESSURE
DEFICIT SHOWS MINIMAL CHANCE OF FOG. NUMERICAL GUIDANCE SHOWS A
BRIEF PERIOD OF MVFR VSBY FOG AT THE TAF SITES GIVEN DECOUPLING OF
WIND LATE AND GOOD RADIATIONAL COOLING CONDITIONS. WILL CONTINUE
FORECAST OF MVFR FOG LATE TONIGHT. ANY FOG LIFTS QUICKLY AFTER
SUNRISE MONDAY.
LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 3 PM SUN...PRED VFR CONDITIONS EXPECTED THROUGH THE PERIOD.
ISOLATED AFTERNOON AND EVENING CONVECTION POSSIBLE WED...WITH
BETTER CHANCES THU AND FRI. PATCHY FOG AND STRATUS POSSIBLE EACH
NIGHT/EARLY MORNING WITH MOIST BOUNDARY LAYER.
&&
.MARINE...
SHORT TERM /THROUGH MONDAY/...
AS OF 705 PM SUNDAY...GENERALLY NORTHEAST WINDS AT 15 KNOTS OR
LESS OVER THE COASTAL WATERS THIS EVENING...BECOMING MORE EAST
LATE TONIGHT AND SOUTHEAST ON MONDAY. SEAS SHOULD CONTINUE IN THE
2 TO 4 FOOT RANGE TONIGHT AND MONDAY.
LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 3 PM SUN...QUIET AND BENIGN BOATING CONDITIONS FOR THE FIRST
PART OF THE PERIOD. SE FLOW MON NIGHT BECOMING SLY TUE. S/SW FLOW
5-15KT WILL CONTINUE TUE THROUGH WED NIGHT...WITH SEAS GENERALLY
2-4FT. CONFIDENCE REMAINS LOW THU AND FRI WITH CONTINUED MODEL
DIFFERENCES AND THE POTENTIAL FOR A STRENGTHENING SFC LOW OFF THE
SE COAST. THE ECMWF CONTINUES TO BE MUCH STRONGER WITH THE LOW
THAN GFS...MOVING THE LOW OFF THE NC COAST FRI/FRI NIGHT...WHILE
THE GFS CONTINUES TO FAVOR A MORE INLAND SOLUTION. PLEASE STAY
TUNED TO LATEST FORECASTS OVER THE NEXT SEVERAL DAYS.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...BTC
NEAR TERM...CTC
SHORT TERM...BTC
LONG TERM...CQD
AVIATION...CTC/CQD
MARINE...CTC/CQD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
241 PM EDT SAT JUN 28 2014
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL SLOWLY DEVELOP OFF THE SOUTHEAST U.S.
COAST THROUGH EARLY NEXT WEEK...AND THIS WILL KEEP THE RISK OF
SHOWERS AND THUNDERSTORMS WITH HEAVY RAIN IN THE FORECAST THROUGH
THE WEEKEND. RIDGING WILL BUILD OVERHEAD NEXT WEEK...BRINGING A
RETURN TO ABOVE NORMAL TEMPERATURES.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 230 PM SATURDAY...A BROAD AREA OF LOW PRESSURE AROUND 120
NM SOUTHEAST OF SOUTH CAROLINA WILL MOVE SLOWLY SOUTH THROUGH THE
NEAR TERM...BRINGING PERIODS OF SHOWERS AND THUNDERSTORMS...MAINLY
TO THE COASTAL COUNTIES. ANALYSIS OF MORNING SOUNDINGS SHOWS THAT
A DEEPLY MOIST AND MARGINALLY UNSTABLE AIRMASS WITH SOME TROPICAL
CHARACTERISTICS WILL CONTINUE TO ADVECT ONSHORE THROUGH THE NEAR
TERM. FOR US THAT MEANS PERIODS OF HEAVY RAIN WITH THE THREAT OF
LOCALIZED FLOODING ALONG THE COAST...BUT OTHERWISE NOT AS MUCH IN
THE WAY OF LIGHTNING AND WITH A MINIMAL CHANCE OF SEVERE WEATHER
IN THE FORM OF DAMAGING WINDS OR LARGE HAIL.
THE HURRICANE CENTER IS FOLLOWING THIS SYSTEM FOR POSSIBLE
DEVELOPMENT AND AT PRESENT GIVES IT A 40 PERCENT CHANCE OF FORMATION
WITHIN THE NEXT 48 HOURS AND 60 PERCENT THROUGH THE NEXT 5 DAYS. IN
ANY CASE...IT IS DRIFTING SOUTHWARD AND EXPECT ITS ASSOCIATED
RAINBANDS TO BE PULLED SOUTH WITH IT. HAVE GRADUALLY DECREASED POPS
THROUGH THE PERIOD AS THIS SOUTHWARD MOVEMENT PROGRESSES.
HAVE CONTINUED TO STAY ON THE HIGH SIDE OF GUIDANCE...AND CLOSE TO
THE LAV...FOR OVERNIGHT MINIMUMS. THIS STRATEGY HAS CONTINUED TO
WORK VERY WELL. THIS WILL GIVE US LOWS OF AROUND 70 FOR MOST
PLACES...WITH MID 70S AT THE COAST.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 230 PM SATURDAY...SURFACE HIGH WILL NOSE IN FROM THE NORTH
WHILE LOW PRESSURE OFF THE FL/GA COAST BECOMES A LITTLE MORE
DEFINED SUN. THIS WILL MAINTAIN LOW LEVEL EAST TO NORTHEAST FLOW
BUT BUILDING 5H RIDGE WILL WORK TO DRY THE MID LEVELS. ALTHOUGH
PRECIPITABLE WATER VALUES WILL DROP BY AROUND HALF AN INCH SUN
THEY WILL STILL BE VERY CLOSE TO CLIMO. THE AFOREMENTIONED MID
LEVEL SUBSIDENCE WILL WORK TO SUPPRESS CONVECTION BUT LOW LEVEL
CONVERGENCE AND LINGERING CONVECTIVE BOUNDARIES WILL STILL BE ABLE
TO DEVELOP SOME ISOLATED ACTIVITY...ESPECIALLY ALONG THE COAST.
UNDER THE 5H RIDGE STORM MOTIONS WILL AGAIN BE UNDER 10 KT AND
STORMS WILL HAVE ABILITY TO PRODUCE SIGNIFICANT RAINFALL TOTALS.
HOWEVER THE OVERALL FLOODING THREAT IS DECREASED GIVEN THE LOWER
EXPECTED COVERAGE. HIGHS CONTINUE TO RUN BELOW CLIMO WITH CLOUD
COVER AND EASTERLY FLOW KEEPING READINGS IN THE MID TO UPPER 80S.
CLOUDS AND MOISTURE WILL HELP KEEP LOWS ABOVE CLIMO...LOW TO MID
70S.
MID LEVEL RIDGING CONTINUES TO STRENGTHEN MON FURTHER DRYING MID
LEVELS WITH INCREASED SUBSIDENCE. CONFIDENCE MON IS ON THE LOW
SIDE...IN PART DUE TO EVOLUTION OF LOW PRESSURE LURKING OFF THE
SOUTHEAST COAST. THE STRENGTHENING MID LEVEL RIDGE AND RESULTING
MID LEVEL DRY AIR/SUBSIDENCE AND THE LACK OF SIGNIFICANT SURFACE
FEATURES WOULD POINT TO PRECIP CHANCES DECREASING LATER IN THE
PERIOD. WILL CARRY LOW CHC POP MON WITH HIGHEST VALUES ALONG THE
COAST. HIGHS WILL CREEP UP A DEGREE OR TWO...NEARING CLIMO...AS
THE 5H RIDGE BUILDS. LOWS CONTINUE TO RUN ABOVE CLIMO.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 300 PM SATURDAY...FOCUS WILL REMAIN ON THE EVOLUTION OF THE
TROPICAL LOW OFF THE SOUTHEAST COAST THROUGH THE WEEK. ON TUESDAY
THE LOW SHOULD BE OFF THE FLORIDA COAST BUT MODELS DIFFER AS TO THE
FATE OF THE LOW THROUGH THE WEEK. AT THE SAME TIME A LOW PRESSURE
SYSTEM OVER THE NORTHERN GREAT LAKES WILL DIG DOWN THROUGH MID WEEK
PUSHING A TROUGH/FRONT EAST THROUGH THURS BEFORE LIFTING OFF TO THE
NORTHEAST BY FRIDAY. THE TROPICAL LOW OR ITS REMNANTS SHOULD GET
PICKED UP BY THIS TROUGH PUSHING EAST. GFS JUST SHOWS SOME
CONVECTION MOVING UP THROUGH THE OFF SHORE WATERS FRI INTO SATURDAY
WHILE THE ECMWF KEEPS A MORE DEFINED SFC LOW TRACKING UP THROUGH THE
OFF SHORE WATERS OFF OF CAPE FEAR FRI REACHING THE WATERS OFF OF
CAPE HATTERAS BY SAT MORNING.
INITIALLY SHOULD SEE WEAK RETURN FLOW AROUND ATLANTIC RIDGE WITH
PIEDMONT TROUGH OVER INLAND AREAS TUES INTO WED. CONVECTION SHOULD
BE MORE ISOLATED THROUGH MID WEEK AS RIDGE REMAINS IN PLACE UP THE
EAST COAST. BY LATE WED INTO THURS MID TO UPPER TROUGH WILL PUSH FAR
ENOUGH EAST TO ENHANCE CONVECTIVE DEVELOPMENT OVER THE
CAROLINAS....MAINLY WELL INLAND. BY LATE THURS INTO FRIDAY...THE
ENTIRE TROUGH PUSHES EAST AS THE REMNANT TROPICAL LOW MOVES UP THE
COAST. SHOULD SEE ADDED SUPPORT FOR CONVECTION TO THE EAST OF THE
TROUGH OVER COASTAL CAROLINAS BEFORE SHIFTING OFF SHORE. FOR NOW IT
LOOKS LIKE THE TROUGH WILL PUSH EAST KEEPING GREATEST CONVECTION
FROM THE LOW WELL OFF SHORE AS HIGH PRESSURE BUILDS INTO THE
CAROLINAS BEHIND FRONT THROUGH LATE FRI INTO SATURDAY. OVERALL IT
LOOKS LIKE BEST CHC OF MORE WIDESPREAD CONVECTION WILL BE WED WELL
INLAND AND LATE THURS INTO FRI OVER MOST OF LOCAL FORECAST AREA.
TEMPS WILL REMAIN ON THE WARMER SIDE OF GUIDANCE IN A MOISTURE RICH
AIR MASS THROUGH MUCH OF THE WEEK. MAX TEMPS WILL BE BETWEEN 90 TO
95 MOST DAYS AND OVERNIGHT LOWS WILL BE AROUND 70.
&&
.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
AS OF 18Z...A LOW PRESSURE AREA TO THE SOUTHEAST OF THE TAF SITES
IS SPIRALING MOISTURE OVER THE AREA TO THE NORTH OF A STATIONARY
FRONTAL BOUNDARY. THIS MOISTURE AND NORTH TO NORTHEASTERLY FLOW
HAS BROUGHT IN LOW CEILINGS AND VISIBILITIES AND THEY ARE LIFTING.
BUT...NOW THE TROPICAL CONVECTION IS OCCURRING MAINLY OVER
ILM...THE LATEST HRRR SHOWS CONVECTION SLOWLY INCREASE NEAR THE
TAF SITES AND WILL HAVE A MENTION OF TS AND VCTS THROUGH LATE
EVENING AT THE OTHER SITES. EXPECT POSSIBLE STRATUS AND FOG AGAIN
OVERNIGHT WITH IFR CONDITIONS POSSIBLE. CONVECTION IS EXPECT AFTER
15 UTC ON SUNDAY.
EXTENDED OUTLOOK...AFTERNOON AND EVENING SHOWERS EXPECTED THROUGH
THE PERIOD POSSIBLY CREATING PERIODS OF MVFR/IFR. OTHERWISE EXPECT
VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 3:00 PM FRIDAY...A BROAD AREA OF LOW PRESSURE AROUND 120 NM
SOUTHEAST OF SOUTH CAROLINA WILL KEEP UP A STEADY NORTHEASTERLY FLOW
OF 10 TO 15 KTS OVER THE WATERS. SEAS WILL STAY IN THEIR PRESENT 2
OR 3 FT RANGE. THE LOW IS PROJECTED TO MOVE SLOWLY SOUTH THROUGH THE
NEAR TERM...BRINGING PERIODS OF SHOWERS AND THUNDERSTORMS TO THE
WATERS THROUGH THE NEAR TERM.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 230 PM SATURDAY...SURFACE HIGH BUILDING IN FROM THE NORTH
AND LOW PRESSURE TO THE SOUTH WILL MAINTAIN EAST TO NORTHEAST FLOW
OVER THE WATERS SUN. WINDS BECOME MORE EASTERLY MON WITH
POTENTIAL FOR SOUTHEAST DIRECTION LATE IN THE PERIOD AS HIGH
PRESSURE MOVES OFF THE MID ATLANTIC COAST AND SETTLES SOUTH.
GRADIENT REMAINS FAIRLY STABLE THROUGH THE PERIOD KEEPING SPEEDS
10 TO 15 KT WITH THE CAVEAT THAT THE LOW OFF THE SOUTHEAST COAST
DOES NOT UNDERGO ANY MEANINGFUL STRENGTHENING DURING THE NEXT 48
HOURS. SEAS WILL RUN 2 TO 3 FT WITH ISOLATED 4 FT POSSIBLE ALONG
OUTER EDGES OF NC ZONES.
LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 230 PM SATURDAY...WEAK RETURN FLOW WILL CONTINUE AROUND
BERMUDA HIGH PRESSURE THROUGH MID WEEK WITH LAND/SEA BREEZE
DOMINATING NEAR SHORE WINDS. TROPICAL LOW SHOULD BE OFF THE COAST
OF FLORIDA ON TUES AND IT SHOULD BEGIN TO TRACK NORTHWARD THROUGH
WED INTO THURS AS TROUGH OVER THE GREAT LAKES DIGS DOWN AND PUSHES
EASTWARD. MODELS DIFFER AS TO INTENSITY OF THIS LOW WITH THE GFS
BEING THE WEAKEST WHILE THE ECMWF TRACKS A 1013 MB LOW OFF THE
NORTH CAROLINA COAST ON FRI. EITHER WAY...WINDS WILL INCREASE OUT
OF THE S-SW WED NIGHT INTO THURS AS GRADIENT TIGHTENS BETWEEN
THESE TWO SYSTEMS. EXPECT WINDS 10 KTS OR LESS TUES INTO WED WITH
SEAS 3 FT OR LESS. INCREASING SOUTHERLY WINDS WED NIGHT INTO THURS
WILL PUSH SEAS UP TO 3 TO 5 FT BY THURS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...REK
SHORT TERM...III
LONG TERM...RGZ
AVIATION...DRH
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
134 PM EDT SAT JUN 28 2014
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL SLOWLY DEVELOP OFF THE SOUTHEAST U.S.
COAST THROUGH EARLY NEXT WEEK...AND THIS WILL KEEP THE RISK OF
SHOWERS AND THUNDERSTORMS WITH HEAVY RAIN IN THE FORECAST THROUGH
THE WEEKEND. RIDGING WILL BUILD OVERHEAD NEXT WEEK...BRINGING A
RETURN TO ABOVE NORMAL TEMPERATURES.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1:30 PM SATURDAY...SHOWERS WITH A VERY TROPICAL FEEL ARE
MOVING SW ALONG THE COASTAL COUNTIES WITH VERY LITTLE ACTIVITY
FURTHER INLAND. HAVE UPDATED POPS TO REFLECT THIS AND HAVE ALSO
LOWERED TEMPERATURES ALONG THE COAST. PREVIOUS DISCUSSION FROM
EARLY THIS MORNING FOLLOWS:
WEAK LOW PRESSURE WAS LOCATED JUST OFFSHORE OF THE SOUTH CAROLINA
COAST THIS MORNING. THIS AREA OF LOW PRESSURE IS EXPECTED TO REMAIN
NEARLY STATIONARY THROUGH THE PERIOD WITH LITTLE INTENSIFICATION
EXPECTED THROUGH TONIGHT.
HOWEVER...THE DEEP AND MOIST CIRCULATION AROUND THIS FEATURE COUPLED
WITH A NEARLY STATIONARY FRONT JUST TO OUR S AND E WILL PROVIDE AN
ENVIRONMENT CONDUCIVE FOR THE DEVELOPMENT OF SHOWERS AND
THUNDERSTORMS AS MOIST AIR IS LIFTED UP AND OVER THE SHALLOW FRONT.
EVEN THOUGH WE WILL BE ON THE OTHER SIDE OF THE FRONT TODAY...THE
AIR MASS IS EVERY BIT AS MOIST AS THAT OF FRIDAY WITH PRECIPITABLE
WATER VALUES UP NEAR 2.25 INCHES. STORM MOTIONS WILL BE SIMILAR TO
FRIDAY...AROUND 5 KT. THE SYNOPTIC SETUP IS A LITTLE BIT DIFFERENT
IN THAT THE GREATEST PROBABILITY FOR HEAVY RAIN AND THE RESULTING
FLOOD RISK WILL BE ALONG AND NEAR THE COAST AS SHOWERS AND
THUNDERSTORMS WRAP CYCLONICALLY AROUND DEVELOPING LOW PRESSURE.
STILL...THE CIRCULATION IS BROAD ENOUGH TO INCLUDE LIKELY POPS FOR
THE ENTIRE FORECAST AREA WITH ABOUT CATEGORICAL FOR MOST OF THE
IMMEDIATE COAST. SOME OF THE HIGHER RESOLUTION MODELS ARE INDICATING
OFFSHORE CONVECTION WILL WRAP INTO THE NEAR SHORE WATERS AND MORE
COASTAL ENVIRONS TO INCLUDE THE BEACHES THIS MORNING.
THE GREATEST RISK FROM THUNDERSTORMS THIS PERIOD WILL AGAIN BE HEAVY
RAIN. SIGNIFICANT PONDING OF WATER IN LOW-LYING AREAS IS LIKELY. THE
RISK FOR FLOODING WILL BE HIGHER TODAY IN COMMUNITIES WHERE HEAVY
RAIN FELL ON FRIDAY. THE PROBABILITY FOR FLOODING WILL BE HIGHEST IN
URBANIZED AREAS. ADDITIONAL RAINFALL AMOUNTS THROUGH TONIGHT WILL
AVERAGE NEAR AN INCH ON THE COAST WITH PREDICTED AMOUNTS TAPERING TO
AROUND A THIRD OF AN INCH WEST OF INTERSTATE 95. HOWEVER...LIKE WE
SAW ON FRIDAY...THE POTENTIAL IS THERE FOR RAINFALL AMOUNTS TO
EXCEED 3 OR 4 INCHES. ONE TO THREE HOUR FLASH FLOOD GUIDANCE IS ON
THE ORDER OF 2.5 TO 3.5 INCHES AND UP TO 4 INCHES. GIVEN THE
HEAVIEST RAIN IS LIKELY TO DEVELOP IN LOCATIONS WHERE THE GUIDANCE
SUGGESTS...RAINFALL AMOUNTS NECESSARY TO CAUSE SIGNIFICANT FLOODING
IS HIGHEST...DECIDED A FLOOD WATCH WAS NOT QUITE WARRANTED AT THIS
TIME.
HIGH MOISTURE CONTENT AND SHOWERS AND THUNDERSTORMS WILL KEEP CLOUDS
PLENTIFUL THROUGH THE PERIOD. THIS WILL IMPACT HIGHS WHICH ARE ONLY
EXPECTED TO REACH THE MID AND UPPER 80S WITH PERHAPS A FEW 90 DEGREE
READINGS ACROSS INLAND PORTIONS OF THE PEE DEE REGION. RAIN COOLED
COMMUNITIES WILL LIKELY DROP INTO THE 70S AND THEN ATTEMPT TO
RECOVER ONCE THE THUNDERSTORMS MOVE OUT. LOWS TONIGHT WILL BE NEAR
70 ACROSS MANY INLAND LOCATIONS WITH LOWER TO MID 70S AT THE COAST.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 AM SATURDAY...DESPITE BUILDING MID LEVEL RIDGE FORECAST
SOUNDINGS ARE NOT INDICATIVE OF ANY SIGNIFICANT DRYING OF THE COLUMN
AS PW REMAINS ABOVE 2 INCHES. SURFACE WAVE WILL HAVE SUNKEN OFF THE
NE FL COAST BY SUNDAY AND HIGH PRESSURE WILL BE LOCATED OFF LONG
ISLAND. COMBINED THIS LEADS TO A CONTINUATION OF ONSHORE FLOW OF LOW
LEVEL MOISTURE. WILL HOLD ON TO A FAIR AMOUNT OF CLOUDINESS AND
SCATTERED POPS A LITTLE HIGHER ALONG THE COAST. THE UPPER RIDGE WILL
WEAKEN SLIGHTLY ON MONDAY WHEREAS IT REMAINS TO BE SEEN WHAT THE
FUTURE HOLDS FOR THE SURFACE SYSTEM. REGARDLESS IT APPEARS TO BE FAR
ENOUGH AWAY IF ITS STILL AROUND TO HAVE MUCH INFLUENCE ON LOCAL
WEATHER. WITH A SMALL DECREASE IN EXPECTED CLOUD COVER MONDAYS HIGHS
SHOULD BE CLOSER TO NORMAL THAN THEIR SUPPRESSED SUNDAY
COUNTERPARTS. THERE SHOULD STILL BE A SCATTERING OF MAINLY AFTERNOON
TSTMS HOWEVER AS NUMEROUS OUTFLOW AND DIFFERENTIAL HEATING
BOUNDARIES WILL LIKELY BE PRESENT.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 300 AM SATURDAY...TUESDAY STILL FINDS A MID LEVEL RIDGE OVER
THE REGION BUT IT WILL BE RATHER BROAD AND OF LOW AMPLITUDE. THIS
RIDGE MOVES OFFSHORE AND STRENGTHENS OVER THE MIDWEEK PERIOD AS
TROUGHINESS TAKES OVER THE GREAT LAKES. IT WILL THUS BE HARD TO PICK
OUT ANY GIVEN DAY WHERE RAIN CHANCES DEVIATE MUCH FROM THE TYPICAL
LOW END CHANCE RANGE...FOLLOWED BY HIGHER VALUES ASSOCIATED THURSDAY
AND FRIDAY WITH A FRONT THAT ENTERS THE AREA AND LIKELY STALLS.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
AS OF 18Z...A LOW PRESSURE AREA TO THE SOUTHEAST OF THE TAF SITES
IS SPIRALING MOISTURE OVER THE AREA TO THE NORTH OF A STATIONARY
FRONTAL BOUNDARY. THIS MOISTURE AND NORTH TO NORTHEASTERLY FLOW
HAS BROUGHT IN LOW CEILINGS AND VISIBILITIES AND THEY ARE LIFTING.
BUT...NOW THE TROPICAL CONVECTION IS OCCURRING MAINLY OVER
ILM...THE LATEST HRRR SHOWS CONVECTION SLOWLY INCREASE NEAR THE
TAF SITES AND WILL HAVE A MENTION OF TS AND VCTS THROUGH LATE
EVENING AT THE OTHER SITES. EXPECT POSSIBLE STRATUS AND FOG AGAIN
OVERNIGHT WITH IFR CONDITIONS POSSIBLE. CONVECTION IS EXPECT AFTER
15 UTC ON SUNDAY.
EXTENDED OUTLOOK...AFTERNOON AND EVENING SHOWERS EXPECTED THROUGH
THE PERIOD POSSIBLY CREATING PERIODS OF MVFR/IFR. OTHERWISE EXPECT
VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1:30 PM SATURDAY...NO CHANGES TO THE FORECAST WITH THE
LATEST UPDATE. PREVIOUS DISCUSSION FOLLOWS:
SHOWERS AND THUNDERSTORMS WERE DEVELOPING ACROSS THE WATERS THIS
MORNING AND WERE MOST NUMEROUS ACROSS THE NEAR SHORE WATERS.
LOW PRESSURE WILL REMAIN WEAK AND NEARLY STATIONARY OFF THE SOUTH
CAROLINA COAST THIS PERIOD. A FRONT IS EXPECTED TO LIE NEAR OR JUST
OFFSHORE OF THE WATERS THROUGH THE PERIOD AS WELL. THIS WILL KEEP
THE PRESSURE GRADIENT RATHER LOOSE. WIND SPEEDS WILL THUS NOT EXCEED
10 TO 15 KT. THE DIRECTION WILL BE E OR NE THROUGH TONIGHT. SEAS
WILL BE A COMBINATION OF WIND AND SWELL ENERGY. TOTAL SEAS WILL BE
MAINLY 3 TO 4 FT. AN 8 TO 10 SECOND ESE SWELL WILL PERSIST.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 AM SATURDAY...LIGHT EAST WINDS ON SUNDAY BROUGHT ABOUT BY
THE DISTANT LOW TO THE SOUTH AS WELL AS HIGH PRESSURE OFF LONG
ISLAND. THOUGH WIND SPEEDS MINIMAL THE EASTERLY/ONSHORE FLOW WILL BE
MAXIMALLY EFFECTIVE AT BRINGING HIGHER OFFSHORE WAVES INTO THE FORECAST
ZONES ALTHOUGH THEY WILL LIKELY BE CAPPED AT 3 FT THEMSELVES. THE
SURFACE LOW MAY STILL BE AROUND TO THE SOUTH WHILE THE OFFSHORE HIGH
DRIFTS EASTWARD. LOCAL FLOW MAY REMAIN EASTERLY OR BEGIN TO VEER. NO
REAL CHANGES IN SPEEDS HOWEVER AND SEAS WILL REMAIN RELATIVELY
UNCHANGED.
LONG TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 300 AM SATURDAY...BARRING TROPICAL DEVELOPMENT SOMEWHERE OFF
THE COAST WIND AND SEAS TO REMAIN QUITE SUMMER LIKE AND MINIMAL. WIND
SPEEDS CAPPED AT 10 KT AND SEAS GENERALLY 2 TO 3 FT. AT SOME POINT
THE WIND IS EXPECTED TO VEER TO THE SOUTH AHEAD OF AN APPROACHING
COLD FRONT...BUT EXACTLY WHEN THIS OCCURS HINGES ON THE YET
UNCERTAIN FATE OF THE AFOREMENTIONED LOW PRESSURE.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MBB
NEAR TERM...REK/RJD
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...DRH
MARINE...REK/RJD/MBB
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
150 AM EDT SAT JUN 28 2014
.SYNOPSIS...
LOW PRESSURE IS EXPECTED TO SLOWLY DEVELOP OFF THE SOUTHEAST U.S.
COAST INTO EARLY NEXT WEEK AND THIS WILL KEEP THE RISK OF SHOWERS
AND THUNDERSTORMS WITH HEAVY RAIN IN THE FORECAST THROUGH THE
WEEKEND. UPPER RIDGING WILL BUILD OVERHEAD NEXT WEEK BRINGING A
RETURN TO ABOVE NORMAL TEMPERATURES.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1045 PM FRIDAY...THE ATMOSPHERE HAS BEEN COMPLETELY OVERTURNED
AND SURFACE-BASED PARCELS ARE CAPPED TO FURTHER DEEP CONVECTION.
ELEVATED INSTABILITY MAY CONTINUE TO FUEL NEW CONVECTIVE ACTIVITY
OVERNIGHT ALTHOUGH THE BEST POTENTIAL FOR THIS IS SHIFTING OFFSHORE.
THROUGH MIDNIGHT THE HIGHEST CHANCE (30-40 PERCENT) OF SHOWERS AND
T-STORMS OVER LAND IS IN THE MYRTLE BEACH VICINITY AND ALONG THE
SANTEE RIVER...BUT THIS POTENTIAL SHOULD WANE AFTER MIDNIGHT WITH
ONLY A 20 POP FORECAST LATE. TEMPERATURES ARE WITHIN A DEGREE OR TWO
OF FORECAST LOWS IN MANY LOCATIONS SO I HAVE ADJUSTED THEM DOWN A
LITTLE...WITH 70-74 NOW FORECAST. PREVIOUS DISCUSSION FROM 730 PM
FOLLOWS...
THE LOWEST PRESSURES OBSERVED ON ASOS/AWOS OBSERVATIONS ARE ABOUT 70
MILES WEST OF GEORGETOWN SC...29.98 INCHES OR ABOUT 1015 MB. THIS IS
AN INTERESTING LITTLE LOW PRESSURE AREA THAT HAS DEVELOPED ALONG A
WEAK COLD FRONT DROPPING SOUTHWARD THROUGH THE CAROLINAS. THE LOW IS
ANTICIPATED TO CONTINUE MOVING SOUTH AND SHOULD PUSH INTO THE
WESTERN ATLANTIC TOMORROW WHERE IT WILL REMAIN FOR SEVERAL DAYS. THE
HURRICANE CENTER HAS A 20 PERCENT CHANCE OF POTENTIAL DEVELOPMENT
FORECAST ON THIS FEATURE WHICH WILL BEAR WATCHING FOR THE NEXT FEW
DAYS.
CLOSER TO HOME...SURFACE-BASED INSTABILITY ON THE ORDER OF 2000-3000
J/KG AND BROAD SURFACE CONVERGENCE INTO THE FRONTAL BAND AND THE
SURFACE LOW LED TO WIDESPREAD THUNDERSTORMS...MANY OF WHICH CONTINUE
INTO THE EVENING HOURS. RADAR HAS ESTIMATED UP TO 4.8 INCHES OF RAIN
NEAR LONGS SOUTH CAROLINA...WITH THE HIGHEST GAUGE-MEASURED TOTALS
INCLUDING 2.48 INCHES IN CONWAY SC...2.36 INCHES IN LUMBERTON
NC...AND 1.57 INCHES AT BACK ISLAND NC (HOLLY SHELTER SWAMP).
THUNDERSTORMS CONTINUE TO DEVELOP ALONG OUTFLOW BOUNDARIES ANYWHERE
THEY CAN FIND BUBBLES OF UNSTABLE AIR THAT HAVEN`T BEEN WORKED OVER
YET. UNTAPPED INSTABILITY REMAINS WEST OF FLORENCE AND SOUTHWARD
TOWARD THE SANTEE RIVER...AND THIS IS WHERE I HAVE THE HIGHEST
POTENTIAL FOR THUNDERSTORMS OVER THE NEXT 2-3 HOURS BEFORE ACTIVITY
WANES OVERNIGHT. CHANGES WITH THIS UPDATE INCLUDE INITIALIZING 100
PERCENT POPS ALONG AND JUST DOWNSTREAM OF CURRENTLY OBSERVED
ACTIVITY...AND USING THE HRRR MODEL AS A GUIDE FOR THE SOUTHWARD
PROPAGATION OF STORMS OVER THE NEXT FEW HOURS.
THE LAST SEVERAL HRRR MODEL RUNS SHOW SOME POTENTIAL FOR NOCTURNAL
CONVECTION OFFSHORE AFTER MIDNIGHT...SO I HAVE INCREASED POPS THERE
EVEN AS I HAVE LOWERED THEM INLAND. NO CHANGES HAVE BEEN MADE TO
OVERNIGHT LOW TEMPERATURE FORECASTS WHICH REMAIN IN THE 72-75
RANGE...WARMEST AT THE SC BEACHES.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 230 PM FRIDAY...REMAINS OF A FRONT STALLED IN THE AREA
ALONG WITH LINGERING OUTFLOW FROM PREVIOUS DAYS CONVECTION WILL
GENERATE SHOWERS AND THUNDERSTORMS ACROSS THE AREA THIS WEEKEND.
SAT CONTINUES TO LOOK LIKE THE BETTER OF THE 2 DAYS WITH DEEP
EASTERLY FLOW CONTINUING TO PUSH DEEP MOISTURE OVER THE SOUTHEAST.
PRECIPITABLE WATER VALUES WILL REMAIN OVER 2 INCHES THROUGH THE
PERIOD. THERE IS ALSO THE SPECTER OF WEAK LOW PRESSURE DEVELOPING
OFF THE COAST ALONG THE STALLED BOUNDARY. WHILE THE CHANCE THIS
SYSTEM DEVELOPS INTO ANYTHING SIGNIFICANT IS LOW IT WILL ENHANCE
LOW LEVEL EASTERLY FLOW...FURTHER INCREASING MOISTURE AND
POTENTIALLY ADDING SOME LOW LEVEL FORCING. BUILDING MID LEVEL
RIDGE...WHILE NOT STRONG ENOUGH TO HAVE MUCH IMPACT SAT...IS
LIKELY TO RESULT IN A DECREASE IN STORM COVERAGE SUN...AS WILL THE
SOUTHWARD/EASTWARD DRIFT OF THE WEAK SURFACE LOW DURING THE SECOND
HALF OF THE PERIOD.
MID LEVEL FORCING WILL BE ALMOST NON-EXISTENT DUE THE BUILD RIDGE.
THIS WILL KEEP STORMS THAT DEVELOP ON THE WEAKER SIDE...LESSENING
THE WIND/HAIL THREAT. IT WILL ALSO RESULT IN STORM MOTIONS THAT ARE
ON THE ORDER OF 5 MPH AND POSSIBLY LESS. DEEP MOISTURE...SLOW STORM
MOTIONS...AND DEEP WARM LAYER(FREEZING LEVEL REMAINS ABOVE 15K FT)
MEAN ANY STORMS THAT DEVELOP WILL HAVE THE POTENTIAL TO CAUSE
FLOODING.
CLOUD COVER AND PRECIP THROUGH THE PERIOD WILL KEEP HIGHS BELOW
CLIMO...MID TO UPPER 80S AND KEEP LOWS ABOVE CLIMO...LOW TO MID 70S.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 300 AM FRIDAY...BUILDING RIDGE ALOFT WILL LEAD TO A WARMING
TREND MOST OF THE UPCOMING WEEK...AHEAD OF A COLD FRONT WHICH WILL
APPROACH ON THURSDAY. SOME DRIER AIR LOCALLY ON MONDAY COMBINED WITH
THE RIDGING ALOFT WILL PROMOTE ONLY ISOLATED CONVECTION CHANCES FOR
EARLY IN THE PERIOD...BUT AS HIGH PRESSURE PUSHES OFFSHORE MOIST
ADVECTION WILL QUICKLY RAMP BACK UP AND CONVECTION CHANCES WILL
INCREASE TUES/WED...WITH THE PIEDMONT TROUGH AND SEA BREEZE
BOUNDARIES BECOMING MORE ACTIVE EACH DAY AS HEAT AND MOISTURE DRIVE
HIGHER INSTABILITY. GUIDANCE SUGGESTS A COLD FRONT WILL CROSS THE
AREA EARLY THURSDAY...BUT ONCE AGAIN...LITTLE TEMPERATURE CHANGE
BEHIND THIS...AS IT SERVES MORE AS A DRYING BOUNDARY THAN A
TEMPERATURE BOUNDARY. WILL SHOW DECREASED POP FOR LATE WEEK BUT WITH
TEMPS REMAINING ABOVE CLIMO FOR THE BEGINNING OF JULY.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 06Z...EXPECT SHOWERS AND THUNDERSTORMS TO BLOSSOM ACROSS THE
WATERS THROUGH THE EARLY MORNING HOURS AND SOME OF THIS ACTIVITY
WILL SPREAD TO THE COASTAL TERMINALS. WILL INCLUDE TEMPO MVFR
VISIBILITIES IN CONVECTIVE RAINS FROM ABOUT 09-10Z THROUGH 12-14Z AT
KMYR/KCRE AND KILM. INLAND...STRATUS PERSISTS AND WILL INCLUDE
CATEGORICAL IFR AT KFLO AND KLBT.
TODAY WILL BE ANOTHER ACTIVE DAY WITH LOW PRESSURE DRIFTING ALONG A
NEARLY STATIONARY BOUNDARY. STORMS COULD POP JUST ABOUT ANY
TIME...ALTHOUGH MAIN FOCUS WILL PROBABLY BE NEAR THE COAST WHERE
STRONGEST LOW PRESSURE WILL RESIDE. STILL LOOKING AT HIGH
PRECIPITABLE WATER VALUES AND SLOW STORM MOTIONS...WHICH INCREASES
THE RISK FOR IFR VISIBILITIES IN HEAVY RAIN.
EXTENDED OUTLOOK...AFTERNOON AND EVENING SHOWERS EXPECTED THROUGH
THE PERIOD POSSIBLY CREATING PERIODS OF MVFR/IFR. OTHERWISE EXPECT
VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 PM FRIDAY...WINDS ARE BACKING TO THE EAST AND NORTHEAST A
LITTLE FASTER THAN EARLIER THOUGHT. THIS IS REFLECTED IN THE 18Z GFS
BUT NOT THE 00Z NAM. NO OTHER SIGNIFICANT CHANGES. PREVIOUS
DISCUSSION FROM 730 PM FOLLOWS...
LOW PRESSURE LOCATED APPROXIMATELY 70 MILES WEST OF GEORGETOWN SOUTH
CAROLINA WILL MOVE SOUTHWARD TONIGHT... PUSHED BY A WEAK COLD FRONT
DROPPING IN FROM THE NORTH. THERE IS VERY LITTLE CHANGE IN AIRMASS
ON EITHER SIDE OF THIS FRONT AND VERY LITTLE REASON TO CALL IT A
"FRONT" OTHER THAN WIND DIRECTIONS SHIFTING FROM THE SOUTH TO MORE
EAST OR NORTHEASTERLY.
PLENTY OF THUNDERSTORM ACTIVITY ACROSS THE COASTAL CAROLINAS THIS
AFTERNOON HAS PUSHED RAIN-COOLED AIR OFFSHORE...ESPECIALLY FROM
MYRTLE BEACH NORTHWARD. THIS HAS LED TO A MUDDLED WIND PATTERN WHERE
INDIVIDUAL THUNDERSTORMS HAVE HAD MORE INFLUENCE OVER WIND
SPEED/DIRECTIONS THAN THE OVERALL SYNOPTIC WIND FLOW. AS
THUNDERSTORMS BECOME LESS NUMEROUS OVERNIGHT LOOK FOR THE EASTERLY
WINDS TO BECOME MORE DOMINANT...ALTHOUGH WITH WIND SPEEDS ONLY
AVERAGING 10 KNOTS.
SEAS CURRENTLY RANGE FROM 1-2 FEET ACROSS THE WATERS. WITH NO
SUBSTANTIAL INCREASE IN WIND SPEEDS ANTICIPATED OVERNIGHT LOOK FOR
LITTLE CHANGE IN SEA HEIGHTS.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 230 PM FRIDAY...SURFACE HIGH TO THE NORTH AND STALLED
DISSIPATING FRONT IN THE AREA...WITH WEAK LOW DEVELOPING ALONG THE
BOUNDARY WILL RESULT IN NORTHEAST TO EAST FLOW ACROSS THE WATERS
THROUGH THE PERIOD. GRADIENT WILL REMAIN LIGHT SO SPEEDS WILL BE
ON THE ORDER OF 10 KT OR LESS THROUGH THE WEEKEND WITH SEAS 2 TO 3
FT.
LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 300 AM FRIDAY...LOW PRESSURE OFF THE SC COAST WILL WEAKEN AND
DRIFT EAST MONDAY...ALLOWING STRENGTHENING HIGH PRESSURE ACROSS THE
ATLANTIC TO BECOME THE DOMINANT FEATURE. THIS CAUSES WINDS TO VEER
FROM NE TO SE ON MONDAY...AND FURTHER TO THE SOUTH ON TUESDAY...BUT
WITH SPEEDS AROUND 10 KTS BOTH DAYS. WAVE HEIGHTS WILL CONTINUE IN
THE 2-3 FT RANGE WITH A VEERING WIND-WAVE AND A CONTINUED SE GROUND
SWELL MAKING UP THE SPECTRUM.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...III
LONG TERM...JDW
AVIATION...43/RJD
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1214 AM EDT SAT JUN 28 2014
.SYNOPSIS...
A FRONT SOUTH OF EASTERN NORTH CAROLINA WILL REMAIN SOUTH OF THE
AREA THROUGH THE BEGINNING OF NEXT WEEK. LOW PRESSURE WILL PUSH
SLOWLY EAST ALONG THE FRONT...MOVING OFFSHORE ON SUNDAY. HIGH
PRESSURE WILL BE OVER THE AREA TUESDAY AS ANOTHER FRONT APPROACHES
FROM THE WEST ON WEDNESDAY. THIS FRONT IS EXPECTED TO PASS THROUGH
THE AREA WEDNESDAY NIGHT WITH UNSETTLED WEATHER THROUGH THE
REMAINDER OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1210 AM SAT...HAVE UPDATED ZONES TO TAKE OUT MENTION OF
PRECIP OVERNIGHT ACROSS MUCH OF THE INLAND COUNTIES. WILL CONTINUE
CHANCE ALONG IMMEDIATE COAST AND OUTER BANKS. HRRR CONTINUES TO
SHOW PRECIP GRADUALLY PUSHING SOUTHWARD THIS EVENING WITH BEST
PRECIP CHANCES ACROSS THE EASTERN HALF OF THE CWA...GENERALLY EAST
OF HIGHWAY 17...AFTER MIDNIGHT AND HAVE TRENDED POPS IN A SIMILAR
FASHION. TEMPS HAVE COOLED TO THE LOW TO MID 70S AND EXPECT LITTLE
CHANGE IN TEMPS THROUGH THE REST OF THE OVERNIGHT.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 AM SUNDAY/...
AS OF 131 PM FRI...STRONG SLOW MOVING STORMS THAT FORMED ALONG THE
SEABREEZE DURING THE AFTERNOON HOURS WILL CONTINUE INTO THE EVENING
HOURS. FRONT SOUTH OF THE AREA WITH LOW PRESSURE ALONG IT COMBINING
WITH UPPER LEVEL ENERGY FOR SCATTERED STORMS ELSEWHERE ACROSS THE
FORECAST AREA. MODELS IN GOOD AGREEMENT ON PLACEMENT OF FRONTAL
BOUNDARY AND ASSOCIATED LOW PRESSURE...KEEPING THEM SOUTH OF THE
AREA THROUGH TONIGHT. UPPER LEVEL ENERGY...COMBINED WITH VARIOUS LOW
LEVEL BOUNDARIES AND DEEP LAYER MOISTURE...WILL KEEP CHANCE OF
ACTIVITY GOING THROUGH THE NIGHTTIME HOURS. SLOW MOVEMENT AND HIGH
PWS COULD PRODUCE SOME LOCALIZED FLOODING. WILL KEEP HIGHEST POPS
ALONG THE SOUTH WITH THE VICINITY OF FRONT/LOW.
&&
.LONG TERM /SUNDAY THROUGH SATURDAY/...
UPPER RIDGE WILL PEAK OVER THE AREA DURING THE LATTER HALF OF THE
WEEKEND. HOWEVER A WEAKNESS IN THE RIDGE TO THE SOUTH ALONG WITH
A STALLED SFC BNDRY TO THE SOUTH WILL CONTINUE TO PROVIDE
SUFFICIENT MOISTURE AND INSTABILITY FOR ISOLATED TO SCATTERED
SHOWERS AND THUNDERSTORMS PARTICULARLY DURING PEAK HEATING SUNDAY
AFTERNOON INTO EARLY EVENING. PARTIAL CLOUDINESS AND AN EAST FLOW
SUGGESTS HIGH TEMPS NEAR CLIMO NORMALS SUNDAY...MAINLY UPPER 80S
INLAND TO LOW 80S AT THE BEACHES.
UPPER RIDGE SETTLES TO THE SW EARLY NEXT WEEK WITH THE LOW-LEVEL
FLOW BECOMING MORE SOUTHERLY AND THE SEMI-PERMANENT PIEDMONT
TROUGH REDEVELOPING BY MIDWEEK. WILL KEEP POPS NEAR CLIMATOLOGY AT
20 TO 30 PCT THROUGH THE EXTENDED PERIOD...HIGHEST AFTN AND
EVENING WHEN INSTAB PEAKS. LOW LVL THICKNESS RIDGE WILL BUILD OVER
THE REGION THRU THE EXTENDED PERIOD..THIS WILL LEAD TO HIGHS OF 85
TO 90 ON MONDAY RISING INTO THE 90 TO 95 DGR RANGE THRU THE MIDDLE
OF NEXT WEEK.
&&
.AVIATION /04Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM /THROUGH SATURDAY/...
AS OF 1210 AM SAT...GENERALLY VFR TO MVFR CONDITIONS AT THE
TERMINALS AT PRESENT BUT WITH ABUNDANT RAINFALL BRINGING A VERY
MOIST BOUNDARY LAYER...EXPECT AREAS OF STRATUS OR FOG THROUGH
ABOUT MID MORNING SAT. MOS GUIDANCE...SREF...NARRES AND HRRR
INDICATING DESCENT CHANCES OF MVFR TO IFR CIGS DEVELOPING WITH
VSBYS MAINLY REMAINING IN THE VFR/MVFR RANGE AND FOLLOWED SUIT IN
THE TAFS. BRINGING IFR CONDITIONS TO ALL TERMINALS EXCEPT EWN
WHERE GUIDANCE IS LEAST BULLISH. A MOIST UNSTABLE AIRMASS
CONTINUES ACROSS THE AREA SAT WITH SCT CONVECTION
POSSIBLE...ESPECIALLY THROUGH THE AFTERNOON HOURS.
LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 145 PM FRI...CONVECTIVE ACTIVITY WILL BE MORE ISOLATED SUN-
TUE. BRIEF PATCHY FOG/STRATUS POSSIBLE EACH NIGHT...ESPECIALLY IN
AREAS WHERE PRECIPITATION OCCURS...AND PERHAPS A BRIEF REDUCTION
TO SUB-VFR IN ANY AFTERNOON AND EVENING CONVECTION THROUGH THE
PERIOD.
&&
.MARINE...
SHORT TERM /TONIGHT AND SATURDAY/
AS OF 1210 AM SAT...WINDS GENERALLY EAST TO NORTHEAST ACROSS THE
MARINE ZONES AND SOUNDS. FORECAST IN GOOD SHAPE. NO CHANGES
PLANNED.
LOW PRESSURE OVER COASTAL SOUTH CAROLINA THIS EVENING WITH
ASSOCIATED FRONT SOUTH OF THE WATERS. THE LOW WILL VERY GRADUALLY
PUSH OFF THE SC COAST THROUGH THE SHORT TERM. GENERALLY ELY FLOW
WILL PREVAIL ACROSS THE WATERS TONIGHT...AROUND 5-15
KT...STRONGEST NORTH OF OREGON INLET AND SOUTH OF OCRACOKE INLET.
WINDS INCREASE TO AROUND 15-20 KT NORTHERN WATERS AND 10-15 KT
SOUTHERN WATERS SATURDAY AS GRADIENTS TIGHTEN BETWEEN HIGH PRES
OFF THE MID-ATLANTIC COAST AND THE LOW OFF THE SC COAST SEAS
AROUND 2 FT THIS EVENING WILL BUILD SLIGHTLY...UP TO 4 FT NRN
WATERS...SAT AS ELY FLOW INCREASES.
LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
HIGH PRES TO THE N AND DEVELOPING WEAK LOW PRESSURE TO THE S WILL
LEAD TO MAINLY E WINDS 10 TO 15 KTS THRU SUNDAY. AS THE HIGH
SLIDES E LOW LVL FLOW WILL BECOME MORE SE MON AND SOUTHERLY BY
TUE. SPEEDS WILL REMAIN MAINLY IN THE 5 TO 15 KT RANGE MON AND
TUE. SEAS WILL AVERAGE 2 TO 4 FEET THRU SUN AND SUBSIDE TO 2 TO 3
FEET MON INTO EARLY TUE. LATER TUE COULD AGAIN SEE SOME 4 FT SEAS
OUTER WATERS AS SRLY WINDS INCREASE A BIT.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...CGG
NEAR TERM...HSA/SK
SHORT TERM...CGG
LONG TERM...BTC/RF
AVIATION...HSA/SK/CGG
MARINE...HSA/SK/BTC
AREA FORECAST DISCUSSION
NWS BISMARCK ND
250 PM CDT SAT JUN 28 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 250 PM CDT SAT JUN 28 2014
THE HEAVY RAIN THREAT WILL CONTINUE OVER CENTRAL NORTH DAKOTA
THROUGH THE LATE AFTERNOON AND EARLY EVENING HOURS. WILL MAINTAIN
THE CURRENT FLASH FLOOD WATCH IN EFFECT UNTIL 00Z AS A RESULT.
SURFACE LOW IS BEGINNING TO TIGHTEN UP AND LIFT NORTH ACROSS
CENTRAL NORTH DAKOTA THIS AFTERNOON. THIS HAS LED TO INCREASING
WIND SPEED AND PERSISTENT LIGHT TO MODERATE RAINFALL ROTATING
SOUTH ACROSS CENTRAL NORTH DAKOTA. THE LATEST HRRR CONTINUES TO
PROG THE LOW TO CONTINUE TO LIFT NORTH INTO CANADA TONIGHT...WITH
PRECIPITATION CHANCES TAPERING OFF FROM SOUTH TO NORTH THIS
EVENING. THINK THE FLOODING THREAT SHOULD END ACROSS THE REGION BY
LATE EVENING.
FOCUS THEN SHIFTS TO THE WINDS ON SUNDAY. THE AFOREMENTIONED LOW
IS PROGGED TO DEEPEN AS IT STALLS OVER LAKE MANITOBA. THIS WILL
TIGHTEN THE GRADIENT FLOW OVER NORTH DAKOTA SUNDAY...LEADING TO
WINDY CONDITIONS DEVELOPING AREAWIDE BY MID-MORNING AND CONTINUING
THROUGH THE AFTERNOON. THE WINDIEST AREAS WILL LIKELY BE IN THE
HIGHER TERRAIN OF SOUTHWESTERN NORTH DAKOTA. HOWEVER...WILL LET
LATER SHIFTS DECIDE ON WHERE AND FOR HOW LONG TO PUT OUT A WIND
ADVISORY (IF WARRANTED) FOR SUNDAY.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 250 PM CDT SAT JUN 28 2014
CYCLONIC FLOW ALOFT WILL CONTINUE OVER NORTH DAKOTA THROUGH
MONDAY...GENERATING A CHANCE OF SCATTERED TO ISOLATED
THUNDERSHOWERS. IN ADDITION...WITH THE SLOWER PROGRESSION OF THE
UPPER LOW IN EXITING THE REGION...A STRONGER SURFACE LOW BENEATH
THE UPPER LOW WILL RESULT IN A STRONG PRESSURE GRADIENT...WILL
BRING GUSTY WEST TO NORTHWEST WINDS MONDAY.
A RIDGE IN THE UPPER LEVEL PATTERN BUILDS OVER THE ROCKIES AND
BEGINS TO PUSH INTO THE DAKOTAS BY TUESDAY
NIGHT/WEDNESDAY...BRINGING SURFACE HIGH PRESSURE AND LITTLE TO NO
CHANCE OF RAIN FOR WEDNESDAY AND THURSDAY.
THE RIDGE FLATTENS BY FRIDAY AND CHANCES OF THUNDERSTORMS RETURN
WITH FAST-MOVING DISTURBANCES IN THE UPPER FLOW THROUGH SATURDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 102 PM CDT SAT JUN 28 2014
MVFR/IFR CONDITIONS IN LIGHT TO MODERATE RAIN SHOWERS WILL
CONTINUE OVER KBIS-KMOT-KJMS THROUGH THE AFTERNOON HOURS.
PRECIPITATION WILL BEGIN TO TAPER OFF FROM SOUTH TO NORTH THIS
EVENING AND OVERNIGHT LEADING TO VFR CONDITIONS DEVELOPING FROM
SOUTH TO NORTH. WESTERLY WIND GUSTS UP TO 30 KNOTS WILL DEVELOP
OVER WESTERN AND CENTRAL NORTH DAKOTA SUNDAY MORNING...WITH WINDY
CONDITIONS CONTINUING THROUGH THE SUNDAY AFTERNOON.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 7 PM CDT /6 PM MDT/ THIS EVENING FOR
NDZ003>005-011>013-018>023-025-033>037-041-042-044>048-050-051.
&&
$$
SHORT TERM...TM
LONG TERM...TM
AVIATION...TM
AREA FORECAST DISCUSSION
NWS BISMARCK ND
102 PM CDT SAT JUN 28 2014
.UPDATE...
ISSUED AT 102 PM CDT SAT JUN 28 2014
NO MAJOR UPDATES WERE REQUIRED TO THE ONGOING FORECAST. OCCASIONAL
RAIN SHOWERS WITH ISOLATED THUNDERSTORMS CONTINUE TO ROTATE OVER
WESTERN AND CENTRAL NORTH DAKOTA THIS AFTERNOON. SURFACE-BASED
CONVECTIVE ACTIVITY IS CURRENTLY NOTED OVER EASTERN MONTANA. THIS
ACTIVITY SHOULD GRADUALLY ADVECT INTO NORTHWESTERN NORTH DAKOTA
BETWEEN 22Z-23Z THIS AFTERNOON...PER THE HRRR SOLUTION. THESE
STORMS SHOULD REMAIN BELOW SEVERE LIMITS.
UPDATE ISSUED AT 1019 AM CDT SAT JUN 28 2014
COPIOUS AMOUNTS OF MOISTURE WILL PERSIST OVER WESTERN AND
CENTRAL NORTH DAKOTA TODAY. THE 12Z KBIS SOUNDING INDICATED PWATS
AROUND 186 PERCENT OF NORMAL THIS MORNING.
THE LATEST HI-RES DETERMINISTIC SOLUTIONS CONTINUE TO INDICATE
WRAP-AROUND MOISTURE/EMBEDDED HEAVY RAIN PERSISTING OVER MOST OF
WESTERN AND CENTRAL NORTH DAKOTA ON THE BACK SIDE OF A SURFACE
LOW THIS MORNING. AS ITS PARENT UPPER LEVEL TROUGH PIVOTS NORTH
THIS AFTERNOON...THE LOW IS FORECAST TO LIFT NORTH INTO
NORTHEASTERN NORTH DAKOTA BY 23Z. PRECIP CHANCES SHOULD BEGIN TO
TAPER OFF FROM SOUTH TO NORTH BY 20Z...WITH THIS TREND CONTINUING
THROUGH LATE EVENING.
NO MAJOR UPDATES WERE REQUIRED TO THE ONGOING FORECAST. THE
UPDATED PRODUCTS HAVE BEEN SENT.
UPDATE ISSUED AT 628 AM CDT SAT JUN 28 2014
FOLLOWED THE 09-10 UTC RAP/HRRR ITERATIONS FOR POPS AND QPF
THROUGH THE REMAINDER OF THE MORNING AND THE AFTERNOON WITH THEIR
CURRENT GOOD HANDLING OF PRECIPITATION PLACEMENT BASED ON RADAR
TRENDS THROUGH 1130 UTC. SEE WPC MESOSCALE PRECIPITATION
DISCUSSION #160 FOR HEAVY RAIN AND FLASH FLOOD THREAT DETAILS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 318 AM CDT SAT JUN 28 2014
THE LATEST WATER VAPOR IMAGERY SHOWS A NEGATIVELY TILTED TROUGH
FROM WESTERN MONTANA INTO KANSAS...WITH A DECENT SHORTWAVE LIFTING
INTO SOUTHERN SOUTH DAKOTA. A DEEPENING SURFACE LOW PRESSURE
IS BEING REFLECTED IN CENTRAL SOUTH DAKOTA...WHICH IS FORECAST TO
SHIFT INTO THE JAMES RIVER VALLEY BY 18Z TODAY...AND THEN INTO THE
TURTLE MOUNTAINS BY 00Z SUNDAY. A COLD FRONTAL SYSTEM HAS BECOME
NEARLY STATIONARY OVERNIGHT WITH THE SOUTHERLY FLOW ALOFT
PARALLELING THIS SURFACE FEATURE. AS THE AFOREMENTIONED SURFACE
LOW SLIDES NORTH ALONG THE STALLED BOUNDARY...EXPECT PRECIPITATION
TO EXPAND TODAY. THIS IS IN LINE WITH THE LATEST HRRR...GFS AND
ECMWF. THUS WENT CATEGORICAL POPS ALONG THE TRACK OF THE LOW...AND
HAVE EXTENDED THE FLOOD WATCH THROUGH EARLY SATURDAY EVENING.
WOULD EXPECT SOME COUNTIES IN THE WEST TO BE SHAVED OFF FROM THE
WATCH AREA DURING THE DAY TODAY AS THE HEAVIER SHOWERS BECOME
FOCUSED MAINLY OVER CENTRAL NORTH DAKOTA. POPS TAPER OFF FROM
SOUTHWEST TO NORTHEAST THIS EVENING AND OVERNIGHT.
FOR THE NEAR TERM...AREAS OF FOG...DENSE AT TIMES IN THE JAMES
RIVER VALLEY...WILL CONTINUE FOR A COUPLE MORE HOURS. AN AREA OF
SHOWERS AND THUNDERSTORMS NOW CROSSING THE SOUTHERN BORDER SHOULD
HELP TO ERODE THIS AREA. ISSUED A NOWCAST TO COVER THIS AS THE
DURATION AND AREAL COVERAGE OF DENSE FOG SHOULD REMAIN MINIMAL.
WILL CONTINUE TO MONITOR AND ADJUST IF NECESSARY.
.LONG TERM...(SUNDAY THROUGH SATURDAY)
ISSUED AT 318 AM CDT SAT JUN 28 2014
THE IMPACTS OF AN ANOMALOUSLY DEEP LOW ACROSS SOUTHERN CANADA SUNDAY
AND MONDAY...FOLLOWED BY A POSSIBLE WARM UP FOR THE FOURTH WILL
HIGHLIGHT THE EXTENDED FORECAST.
A -3.5 STANDARD DEVIATION LOW ACROSS SOUTHERN MANITOBA
SUNDAY...AND INTO WESTERN ONTARIO MONDAY WILL YIELD A WINDY PERIOD
SUNDAY AND MONDAY SOUTH OF THE LOW ACROSS WESTERN AND CENTRAL
NORTH DAKOTA. WIND GUSTS TO 40 MPH ARE POSSIBLE ON SUNDAY...WHICH
IS JUST SHY OF ADVISORY. FOR SUNDAY...SCATTERED TO WIDELY
SCATTERED RAIN SHOWER AND THUNDERSTORM ACTIVITY WILL REMAIN ACROSS THE
US HIGHWAY 2 CORRIDOR WITH A DRY SLOT ACROSS SOUTHERN NORTH
DAKOTA. FOR MONDAY...GREATER WRAP AROUND MOISTURE AND COLD AIR
ALOFT SUPPORT NUMEROUS SHOWERS WITH EMBEDDED THUNDERSTORMS THROUGH
THE DAY ON MONDAY...ENHANCED BY AFTERNOON HEATING. A POTENTIAL
WARM UP WITH HIGHS WELL INTO THE 80S IS SUGGESTED BY THE 00 UTC
DETERMINISTIC AND ENSEMBLE SUITE FOR THE FOURTH AND THE FIFTH WITH
A BROAD...LOW AMPLITUDE UPPER LEVEL RIDGE CENTERED ACROSS THE
CENTRAL CONUS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 102 PM CDT SAT JUN 28 2014
MVFR/IFR CONDITIONS IN LIGHT TO MODERATE RAIN SHOWERS WILL
CONTINUE OVER KBIS-KMOT-KJMS THROUGH THE AFTERNOON HOURS.
PRECIPITATION WILL BEGIN TO TAPER OFF FROM SOUTH TO NORTH THIS
EVENING AND OVERNIGHT LEADING TO VFR CONDITIONS DEVELOPING FROM
SOUTH TO NORTH. WESTERLY WIND GUSTS UP TO 30 KNOTS WILL DEVELOP
OVER WESTERN AND CENTRAL NORTH DAKOTA SUNDAY MORNING...WITH WINDY
CONDITIONS CONTINUING THROUGH THE SUNDAY AFTERNOON.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 7 PM CDT /6 PM MDT/ THIS EVENING FOR
NDZ003>005-011>013-018>023-025-033>037-041-042-044>048-050-051.
&&
$$
UPDATE...TM
SHORT TERM...KS
LONG TERM...AYD
AVIATION...TM
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1215 AM CDT SAT JUN 28 2014
.UPDATE...
ISSUED AT 1215 AM CDT SAT JUN 28 2014
THE LATEST LOCAL/REGIONAL RADAR AND WATER VAPOR SHOWS A COUPLE OF
NICELY DEFINED SHORTWAVES ROTATING NORTH FROM SOUTH DAKOTA AND
NEBRASKA. ONE SHORTWAVE NEAR FAITH SOUTH DAKOTA IS MOVING NORTH
WITH CATEGORICAL POPS CONTINUING IN THE SOUTHWEST. THIS SHORTWAVE
MAINTAINS A NORTHWARD PROGRESSION OVERNIGHT AND HAVE UPPED POPS
FARTHER NORTH ACROSS NORTH CENTRAL NORTH DAKOTA. A MORE IMPRESSIVE
SHORTWAVE IN CENTRAL NEBRASKA IS SUPPORTING A DEVELOPING SURFACE
LOW NEAR PIERRE SOUTH DAKOTA. THIS LOW WILL DEEPEN OVERNIGHT AND
MOVE TOWARDS THE JAMES RIVER VALLEY BY 18Z SATURDAY...THEN INTO
THE TURTLE MOUNTAINS BY 00Z SUNDAY. CONSEQUENTLY...THIS LOW WILL
SLIDE NORTH ALONG A VERY SLOW MOVING COLD FRONT IN CENTRAL NORTH
DAKOTA SETTING THE STAGE FOR PERSISTENT MODERATE TO HEAVY RAIN
SHOWERS AND THUNDERSTORMS. THUS THE FLOOD WATCH AND THREAT FOR
HEAVY RAINFALL/FLOODING CONTINUES. CURRENT MODEL GUIDANCE NOT
HANDLING THE CURRENT PRECIPITATION AREA...AND RELIED MAINLY ON
UPSTREAM TRENDS FOR THE OVERNIGHT PERIOD WHICH INDICATE WIDESPREAD
DEVELOPMENT INTO SOUTH CENTRAL NORTH DAKOTA BY 07Z SATURDAY. WENT
CATEGORICAL POPS ACROSS MOST OF SOUTHERN NORTH DAKOTA REST OF THE
OVERNIGHT PERIOD.
UPDATE ISSUED AT 953 PM CDT FRI JUN 27 2014
MAIN ISSUE FOR THE LATE EVENING UPDATE WAS TO DROP THE FLASH FLOOD
WATCH FOR PORTIONS OF THE NORTHWEST. ALSO DROPPED THE MENTION OF
SEVERE WEATHER TONIGHT...AND UPDATED POPS BASED ON LATEST RADAR
TRENDS. SHORTWAVE MOVING THROUGH SOUTH DAKOTA CONTINUES TO PRODUCE
THUNDERSTORMS WITH HEAVY RAIN ALONG A SLOW MOVING BOUNDARY ACROSS
CENTRAL NORTH DAKOTA. THIS HAS ENDED THE HEAVY RAIN THREAT IN THE
NORTHWEST. ALTHOUGH AN ISOLATED SEVERE STORM WITH QUARTER SIZED
HAIL OR LOCALLY GUSTY WINDS CAN NOT BE RULED OUT THE GREATEST
THREAT FOR THE REMAINDER OF THE NIGHT WILL BE THUNDERSTORMS
PRODUCING VERY HEAVY RAINFALL.
UPDATE ISSUED AT 716 PM CDT FRI JUN 27 2014
MAIN FORECAST ISSUE THIS EVENING WAS TO CLEAR UP POP FORECAST.
AREA OF SHOWERS AND THUNDERSTORMS THAT LIFTED NORTH THROUGH THE
JAMES RIVER VALLEY HAS PRETTY MUCH CLEARED THE FORECAST AREA. BUT
DID KEEP SOME SMALL POPS IN THE EAST AND CHANCE POPS NORTHEAST
THIS EVENING. FOCUS IS NOW IN THE SOUTHWEST WHERE NUMEROUS SHOWERS
AND THUNDERSTORMS OVER WESTERN SOUTH DAKOTA CONTINUE TO LIFT
NORTHEAST INTO SOUTHWEST NORTH DAKOTA. HAVE INCREASED POPS OVER
THIS AREA THIS EVENING...AND SPREAD IT INTO THE SOUTH CENTRAL LATE
THIS EVENING AND OVERNIGHT. IN ADDITION SEVERAL FUNNEL CLOUDS HAVE
BEEN REPORTED RECENTLY IN THE MOTT TO HETTINGER AND LEMON SD AREA.
LCL HEIGHTS REMAIN LOW IN THIS AREA WITH A NON SUPERCELL TORNADO
PARA MATER MAXIMA IN THIS AREA.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 257 PM CDT FRI JUN 27 2014
MCV OVER NORTH CENTRAL SOUTH DAKOTA CONTINUES TO LIFT NORTH THIS
AFTERNOON. THIS FEATURE HAS SPARKED THUNDERSTORM ACTIVITY OVER
THE JAMES RIVER VALLEY EARLY THIS AFTERNOON. THE LATEST HRRR PROGS
THIS MCV AND ATTENDANT CONVECTIVE ACTIVITY TO CONTINUE TO MOVE
NORTH ACROSS EAST-CENTRAL NORTH DAKOTA LATE THIS AFTERNOON. DO
NOT SEE ANY REASON TO DEVIATE FROM THIS FORECAST...SO KEPT LIKELY
POPS GOING FOR THE EASTERN CWA.
THE SHORT RANGE MODELS CONTINUE TO PAINT A WET PICTURE ACROSS THE
STATE TONIGHT THROUGH SATURDAY AS A NEGATIVELY TILTED TROUGH
PIVOTS OVER THE DAKOTAS. NOT REAL CONFIDENT IN THUNDERSTORMS
BECOMING SEVERE LATE THIS AFTERNOON AND EVENING. HOWEVER...AM NOT
CONFIDENT ENOUGH TO REMOVE SEVERE WORDING FROM THE FORECAST EITHER.
FOR NOW WILL KEEP THE SEVERE WORDING IN THE ZONES FOR THIS
UPDATE...AND CONTINUE THE FLASH FLOOD WATCH THROUGH 12Z SATURDAY.
WILL ALLOW LATER SHIFTS DECIDE IF THE WATCH WILL NEED TO BE
EXTENDED IN TIME BASED ON HOW THE CONVECTIVE ACTIVITY EVOLVES.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 257 PM CDT FRI JUN 27 2014
THUNDERSTORM CHANCES ON SATURDAY NIGHT AND STRONG WINDS ON SUNDAY
AND MONDAY WILL HIGHLIGHT THE EXTENDED FORECAST.
SATURDAY NIGHT THE UPPER LEVEL TROUGH EXTENDS FROM THE UPPER LOW
OVER ALBERTA/BRITISH COLUMBIA...AND LIFTS NORTHEASTWARD THROUGH THE
NIGHT. EXPECT SCATTERED THUNDERSTORMS SATURDAY NIGHT BUT NO SEVERE
WEATHER EXPECTED.
AS THE UPPER TROUGH LIFTS NORTHEASTWARD SATURDAY NIGHT...THE UPPER
LOW MOVES/DEVELOPS EASTWARD INTO SOUTHERN
SASKATCHEWAN/MANITOBA...WHERE IT REMAINS THROUGH SUNDAY...BEFORE
FINALLY LIFTING NORTHEASTWARD TOWARDS HUDSON BAY ON MONDAY. THIS
SCENARIO WILL KEEP A CYCLONIC FLOW ALOFT OVER NORTH DAKOTA THROUGH
MONDAY...AND HENCE A CHANCE OF SCATTERED TO ISOLATED THUNDERSHOWERS.
IN ADDITION...WITH THE SLOWER PROGRESSION OF THE UPPER LOW IN
EXITING THE REGION...A STRONGER SURFACE LOW BENEATH THE UPPER LOW
WILL RESULT IN A STRONG PRESSURE GRADIENT...AND BRING GUSTY WEST TO
NORTHWEST WINDS TO THE FORECAST AREA SUNDAY AND MONDAY.
A RIDGE IN THE UPPER LEVEL PATTERN BUILDS OVER THE ROCKIES AND
BEGINS TO PUSH INTO THE DAKOTAS BY TUESDAY
NIGHT/WEDNESDAY...BRINGING SURFACE HIGH PRESSURE AND LITTLE TO NO
CHANCE OF RAIN FOR WEDNESDAY AND THURSDAY.
THE RIDGE FLATTENS BY FRIDAY AND CHANCES OF THUNDERSTORMS RETURN
WITH FAST-MOVING DISTURBANCES IN THE UPPER FLOW.
A WARMING TREND WITH HIGHS 65 TO 75 MONDAY...WARMING TO 75 TO 85 BY
THURSDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1215 AM CDT SAT JUN 28 2014
WIDESPREAD/NUMEROUS SHOWERS AND THUNDERSTORMS WILL SPREAD FROM
KDIK INTO KBIS AND KMOT SHORTLY AFTER 06Z SATURDAY. THIS
PRECIPITATION WILL SLOWLY EXPAND INTO THE JAMES RIVER VALLEY/KJMS
TERMINAL SATURDAY MORNING. MVFR CIGS/VSBYS WILL ACCOMPANY THE
PRECIPITATION WITH BRIEF PERIODS OF IFR CONDITIONS POSSIBLE IN THE
HEAVIEST PRECIPITATION AREAS. EXPECT SHOWERS AND THUNDERSTORMS
TO CONTINUE THROUGH SATURDAY EVENING BEFORE DWINDLING FROM
SOUTHWEST TO NORTHEAST.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 7 AM CDT /6 AM MDT/ THIS MORNING FOR
NDZ003>005-011>013-018>023-025-033>037-040>048-050-051.
&&
$$
UPDATE...KS
SHORT TERM...TM
LONG TERM...JV
AVIATION...KS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1137 PM CDT FRI JUN 27 2014
.UPDATE...
ISSUED AT 944 PM CDT FRI JUN 27 2014
MADE SOME MINOR ADJUSTMENTS TO THE POP/WX FORECAST FOR TONIGHT.
THE FIRST UPPER WAVE IS SLOWLY PROPAGATING NORTH/NORTHEAST...AND
SHOULD BRING AN AREA OF SHOWERS TO THE EASTERN FA OVER THE NEXT
SEVERAL HOURS (ADJUSTED POPS TO ACCOUNT FOR EXPECTED TIMING OF
THESE SHOWERS). OTHERWISE...MUCH OF THE NIGHT STILL EXPECTED TO BE
MOSTLY DRY WITH INCREASING ACTIVITY AFTER SUNRISE. SEE 728 PM
UPDATE CONCERNING FLASH FLOOD CONCERNS.
UPDATE ISSUED AT 728 PM CDT FRI JUN 27 2014
FLASH FLOOD POTENTIAL THROUGH SATURDAY...AND PRECIP COVERAGE
TONIGHT WILL BE THE MAIN CHALLENGES. THE UPPER WAVE RESPONSIBLE
FOR THE CURRENT ACTIVITY CAN BE SEEN IN THE RADAR IMAGERY...JUST
ENTERING EXTREME SOUTHEAST NORTH DAKOTA. THIS WAVE WILL BE EXITING
THE REGION BY 06Z...AND SIGNIFICANTLY LOWERED POPS TO ACCOUNT FOR
THE EXPECTED BREAK IN ACTIVITY LATER THIS EVENING. MOST AREAS HAVE
RECEIVED A TRACE TO AN INCH OF RAIN...WITH ISOLATED AREAS UP TO 2
INCHES...AND VERY LOCALIZED AREAS UP TO 3 INCHES. ALTHOUGH FLASH
FLOODING WILL NOT BE A THREAT THIS EVENING/OVERNIGHT...STILL
CONCERNED WITH THE NEXT WAVE APPROACHING FROM THE SOUTHWEST. THE
FEATURE APPEARS TO BE STRONGER...AND SHOULD BE INTERACTING WITH A
SIMILAR AIRMASS (HIGH PWATS...LOW INSTABILITY). SO...THIS FIRST
WAVE OF ACTIVITY HAS SET THE STAGE FOR POTENTIAL FLASH FLOODING ON
SATURDAY. THE AREA OF THE FLASH FLOOD WATCH STILL APPEARS
REASONABLE GIVEN THE EXPECTED TRACK OF THE UPPER WAVE.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 220 PM CDT FRI JUN 27 2014
THE MAIN CHALLENGE WILL BE HEAVY RAINFALL THROUGH SATURDAY. THE
MODELS ARE IN DECENT AGREEMENT...BUT STILL DIFFERENCES IN OVERALL
EVOLUTION OF CONVECTION. THE HRRR IS DOING A GOOD JOG IN THE NEAR
TERM...AND THE NAM/GFS ARE NOT TOO BAD WITH LARGE SCALE FEATURES
INTO SUNDAY.
FOR THE REST OF THIS AFTERNOON THROUGH SAT...THE THREAT FOR HEAVY
RAIN IS BECOMING MORE LIKELY...AND WE WILL ISSUE A FLASH FLOOD
WATCH ALONG AND WEST OF THE VALLEY THROUGH 18Z SUNDAY. THERE IS A
SHORTWAVE/MCV THAT WILL LIFT NORTH AND AFFECT THE DVL BASIN AND
THE VALLEY. EXPECT VIGOROUS CONVECTION WITH TORRENTIAL
RAIN...SOME SMALL HAIL AND PERHAPS SOME WIND GIVEN THE HIGH
MOISTURE...PWATS TO 1.75 INCHES LATER TONIGHT AND MUCAPE TO 3000
J/KG. THE LIMITING FACTOR FOR SEVERE WEATHER THROUGH TONIGHT AN
EVEN INTO SAT WILL BE FAIRLY WEAK DEEP LAYERED SHEAR ONLY AROUND
25-30KT. GIVEN THE HIGH INSTABILITY AND 70 DEWPOINTS...WE CAN
NEVER TOTALLY RULE OUT SEVERE STORMS. WE WILL MENTION HEAVY RAIN IN
THE GRIDS THROUGH SATURDAY. THE THREAT FOR HEAVY RAIN INTO THE MN
COUNTIES LATER TONIGHT AND SAT WILL NEED TO BE MONITORED...WITH
HEAVY RAIN POSSIBLE ANYWHERE A THUNDERSTORM CAN DEVELOP IN THIS
TROPICAL ENVIRONMENT. THE MAIN SHORTWAVE TROUGH WILL LIFT THROUGH
THE REGION SATURDAY...AND ANOTHER ROUND OF SHOWERS AND STORMS ARE
LIKELY AFTER PERHAPS A BREAK DURING THE MORNING WITH MAINLY
DIURNALLY DRIVEN STORMS...SINCE THE LLJ IS NOT THAT STRONG AROUND
30-35KT OR SO. ONCE AGAIN...THE MAIN THREAT IS HEAVY RAIN WITH
DEEP LAYERED SHEAR FAIRLY WEAK BUT A BIT STRONGER THAN TODAY...SO
ONCE AGAIN A FEW SEVERE STORMS POSSIBLE WITH HAIL/WIND. THERE WILL
BE SOME AREAS THAT COULD RECEIVE VERY HEAVY RAINFALL AMOUNTS IN
EXCESS OF 3 INCHES...PERHAPS MORE WHERE STORMS PERSIST FOR ANY
LENGTH OF TIME THROUGH SATURDAY.
ON SAT NIGHT...THERE WILL BE A DRYING TREND FROM WEST TO EAST AND
THE ORGANIZED CONVECTIVE THREAT SHOULD END.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 220 PM CDT FRI JUN 27 2014
ON SUNDAY...A STRONG LOW WILL WRAP UP IN CANADA WITH STRONGER
WINDS POSSIBLE NEAR THE CANADIAN BORDER. THERE WILL BE THE
CONTINUED THREAT FOR SHOWERS AND A FEW STORMS MAINLY IN THE NORTH.
FOR MONDAY...IT SHOULD BE COOL AND THE POTENTIAL FOR MORE SHOWERS
AND PERHAPS A STORM. THERE WILL STILL BE HIGH PWATS OVER 1.25
INCHES IN THE NORTH...SO MORE LOCALLY HEAVY RAINFALL CAN/T BE
RULED OUT.
LARGE UPPER LOW WILL DEPART THE AREA TO THE EAST TUESDAY WITH A
LINGERING LOW CHANCE FOR DIURNAL SHOWERS. THEN DRIER AIR WORKS IN
FOR WED-THU BEFORE NEXT SYSTEM ARRIVES BRINGING CHANCE FOR
THUNDERSTORMS THURSDAY NIGHT INTO FRIDAY. GFS/ECMWF HAVING RUN TO
RUN ISSUES IN REGARDS TO WHETHER THERE WILL BE AN UPPER RIDGE
BUILDING OVER THE NRN PLAINS LATE IN THE WEEK OR A FLATTER ZONAL
FLOW. HOWEVER IT DOES APPEAR A SHORT WAVE WILL IMPACT NORTH
DAKOTA/NRN MN LATE WEEK BUT UNLIKE THE PAST TWO SYSTEMS MAY NOT
LINGER AROUND AS LONG AS IT MOVES EAST FRI NIGHT-SATURDAY. LATE
WEEK MAY TURN QUITE WARM AND VERY HUMID.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1137 PM CDT FRI JUN 27 2014
VERY DIFFICULT FORECAST AND CONFIDENCE IS LOW. LOWER CIGS SHOULD
CONTINUE TO DEVELOP AND AFFECT MOST TAF SITES AT SOME POINT BEFORE
SUNRISE. SHOWERS/THUNDERSTORMS WILL BE WIDELY SCATTERED...THEN
INCREASE IN COVERAGE BY LATER SATURDAY MORNING (AT LEAST ALONG AND
WEST OF THE VALLEY).
&&
.HYDROLOGY...
ISSUED AT 1250 PM CDT FRI JUN 27 2014
CANCELLED THE RIVER FLOOD WARNINGS FOR THE S BUFFALO RIVER AT SABIN
WHERE RIVER LEVELS DROPPED BELOW FLOOD STAGE AND FOR THE TWO RIVERS
RIVER AT HALLOCK...WHERE STAGES PEAKED JUST BELOW FLOOD STAGE. THE
RED RIVER AT FARGO CONTINUES TO DECLINE...WHILE RIVER STAGES ARE
HOLDING FAIRLY STEADY FROM EAST GRAND FORKS TO DRAYTON. OSLO IS THE
ONLY FORECAST POINT THAT REMAINS IN MODERATE FLOOD STAGE. PLACEMENT
AND COVERAGE OF THE HEAVIER RAINFALL THIS WEEKEND WILL DETERMINE
POTENTIAL IMPACTS FOR AREA RIVERS AND STREAMS.
SHOWERS AND THUNDERSTORMS THIS AFTERNOON THROUGH SATURDAY NIGHT WILL
POSE THE RISK FOR LOCALLY HEAVY RAINFALL. THUS...FLOODING CONCERNS
WILL NEED TO BE MONITORED THROUGH THE WEEKEND.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...FLASH FLOOD WATCH THROUGH SATURDAY AFTERNOON FOR NDZ006>008-
014>016-024-026>030-038-039-049-052>054.
MN...FLASH FLOOD WATCH THROUGH SATURDAY AFTERNOON FOR MNZ001>004-007-
029.
&&
$$
UPDATE...TG
SHORT TERM...DK
LONG TERM...DK/RIDDLE
AVIATION...TG
HYDROLOGY...MAKOWSKI
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
402 PM EDT SAT JUN 28 2014
.SYNOPSIS...
A WARM AND HUMID AIR MASS WILL CONTINUE TO SUPPORT OCCASIONAL
SHOWERS AND THUNDERSTORMS THROUGH THE WEEKEND. ADDITIONAL WEATHER
DISTURBANCES MOVING EAST THROUGH THE OHIO VALLEY WILL ALLOW FOR
THE CHANCE OF STORMS TO CONTINUE INTO THE MIDDLE OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
A VERY MOIST AIR MASS IS NOW IN PLACE ACROSS THE ENTIRETY OF THE
ILN FORECAST AREA. A WEAK FRONTAL BOUNDARY IS NOW STRETCHING
ACROSS CENTRAL OHIO FROM NNW-TO-SSE. TO THE SOUTHWEST OF THIS
BOUNDARY...CONDITIONS WERE RAINY AND CLOUDY FOR MUCH OF THE
MORNING...WHICH HAS HINDERED RISES IN TEMPERATURES.
HOWEVER...LAPS ANALYSIS SHOWS THAT INSTABILITY VALUES ARE SIMILAR
ON EITHER SIDE...AS DEWPOINTS REMAIN HIGHER TO THE SOUTHWEST.
NONETHELESS...THE MOST ACTIVE CONVECTION HAS DEVELOPED NEAR THE
FRONT...WHERE HEATING WAS MAXIMIZED AND CONVERGENCE IS ALSO
PRESENT.
PRECIPITABLE WATER VALUES ARE WELL OVER AN INCH AND A HALF...AND
SLOW STORM MOTIONS WILL LIKELY CONTRIBUTE TO THE OCCASIONAL THREAT
OF HEAVY RAINFALL. SOME OF THE STRONGER CORES ALSO PRODUCED BRIEF
STRONG DOWNDRAFT WINDS (DEPICTED ON TCMH) EARLIER...AND A FEW
STRONG WIND GUSTS WILL REMAIN POSSIBLE...THOUGH ONLY WITH THE MOST
INTENSE OF THE CONVECTION. THE SPECIFICS ON
TIMING...PLACEMENT...AND INTENSITY ACROSS THE CWA ARE NOT AS
CERTAIN AS WOULD BE IDEAL. HIGH-RESOLUTION MODELS SHOW A
DIMINISHING TREND AFTER 21Z...WITH THE AXIS OF GREATEST ACTIVITY
MOVING NORTHEAST WITH TIME. HOWEVER...THERE IS A LOT OF ADDITIONAL
DEVELOPMENT OVER SOUTHERN INDIANA AND CENTRAL KENTUCKY...SO THIS
MAY NOT BE AS QUICK A DIMINISHING TREND AS THE HRRR (FOR EXAMPLE)
IS FORECASTING.
BY OVERNIGHT...CONDITIONS ARE EXPECTED TO BE REDUCED TO SCATTERED
SHOWERS...WITH MUCH OF THE CWA DRYING OUT FOR A WHILE GOING INTO
THE MORNING HOURS ON SUNDAY. WITH NO CHANGE TO THE MOIST
CONDITIONS...WARM MIN TEMPS CAN BE EXPECTED (NEAR 70 DEGREES).
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/...
THOUGH CONDITIONS MAY BE MOSTLY DRY ACROSS THE CWA ON SUNDAY
MORNING...A WEAK MID-LEVEL SHORTWAVE IN THE SOUTHWESTERLY FLOW
WILL BEGIN MOVING EAST THROUGH THE OHIO VALLEY. WITH LITTLE CHANGE
TO THE AIR MASS...SHOWERS AND STORMS WILL AGAIN BE POSSIBLE...WITH
TIMING ACROSS THE ILN CWA APPEARING TO BE MAXIMIZED DURING THE
PEAK OF THE DIURNAL CYCLE. HEADING INTO MONDAY NIGHT...THE AXIS OF
THE SHORTWAVE WILL BE PASSING THE REGION...AND SLIGHTLY DRIER AIR
WILL BE FILTERING INTO THE NORTHWESTERN HALF OF THE CWA.
WITH AN EXPECTATION FOR CLOUDS AND MOIST CONDITIONS...MAX TEMPS
FOR MONDAY WERE BROUGHT DOWN A COUPLE DEGREES FROM THE PREVIOUS
FORECAST...ESPECIALLY IN THE NORTHWEST HALF OF THE CWA. SIMILAR
MIN TEMPS ARE EXPECTED MONDAY NIGHT IN COMPARISON TO SUNDAY NIGHT.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
LARGE SCALE MID LEVEL TROUGH WILL BE SLOWLY MOVING THROUGH SOUTH
CENTRAL CANADA AND THE NORTHERN PLAINS ON MONDAY. A COLD FRONT WILL
BE ASSOCIATED WITH THIS SYSTEM...BUT THIS FEATURE WILL NOT ARRIVE
INTO OUR REGION UNTIL TUESDAY. IN THE MEANTIME...MINOR DISTURBANCES
IN THE FLOW ALOFT COMBINED WITH DAYTIME HEATING WILL RESULT IN
TYPICAL CHANCE POPS FOR SHOWERS/STORMS FOR THIS TIME OF THE YEAR ON
MONDAY.
LARGE SCALE MID LVL TROUGH WILL CONTINUE TO DIG SOUTHEAST INTO THE
GREAT LAKES MONDAY NIGHT INTO TUESDAY NIGHT. THIS SCENARIO WILL
SLOWLY PUSH AFOREMENTIONED COLD FRONT INTO THE REGION ON
TUESDAY...WITH THE BOUNDARY SLOWING UP AS IT PUSHES INTO THE
ERN/SERN CWFA TUESDAY NIGHT. MAIN UPR LVL DYNAMICS REMAIN TO THE
NORTH AND NORTHWEST...SO CHANCES OF SHOWERS/STORMS WILL BE DEPENDENT
ON DAYTIME HEATING AND FRONTAL CONVERGENCE. HAVE RAMPED POPS UP TO A
LEAST 50 FOR NOW AS AM NOT CONVINCED IF CONVERGENCE WILL BE STRONG
ENOUGH FOR LIKELY POPS TUESDAY AFTERNOON/EARLY EVENING. POPS WILL
WANE TUESDAY NIGHT AND WILL REMAIN IN THE EAST/SRN ZONES DUE TO THE
FRONT IN THE PROXIMITY.
FOR WEDNESDAY INTO THURSDAY...LATEST MODEL RUNS SHOW SOME ADDITIONAL
ENERGY MERGING INTO THE LARGE SCALE TROUGH AS IT DIGS SLOWLY INTO
THE GREAT LAKES. FIRST FRONTAL BOUNDARY MAY EXIT OUR SE AND PERHAPS
DISSIPATE ON WEDNESDAY WHILE ANOTHER COLD FRONT APPROACHES THE
REGION FROM THE NORTHWEST. TIMING AND FRONTAL CONVERGENCE OUR IN
QUESTION FOR THE NEXT FRONT AT THIS POINT IN TIME SO HAVE GONE WITH
CHANCE POPS WEDNESDAY/WEDNESDAY NIGHT...WITH POPS DECREASING FROM
WEST TO EAST ON THURSDAY AS THE FRONT PUSHES EAST.
LARGE SCALE TROUGH WILL PUSH INTO SE CANADA AND THE CENTRAL/ERN
GREAT LAKES THURSDAY NIGHT INTO FRIDAY AS SURFACE HIGH PRESSURE
BUILDS INTO THE REGION FROM THE WEST. THIS WILL OFFER A DRIER AND A
LITTLE COOLER AIRMASS.
AFOREMENTIONED SFC HIGH REMAINS OVER THE REGION ON SATURDAY WHILE
THE MID LEVEL TROUGH EXITS EAST. MODELS SUGGEST THAT MID LVL RIDGING
WILL TRY TO BUILD IN FROM THE WEST.
AS FOR TEMPERATURES...WARM AND MUGGY CONDITIONS WILL CONTINUE MONDAY
THROUGH WEDNESDAY. DRIER AIR AND TEMPERATURES IN THE UPPER 70S TO
THE LOWER 80S ARE EXPECTED BY THURSDAY AND FRIDAY. TEMPERATURES WILL
THEN MODIFY ON SATURDAY WITH 80S EXPECTED FOR HIGHS.
&&
.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
SCATTERED SHOWER ACTIVITY WILL AFFECT KCVG AND KLUK WITH SOME
THUNDERSTORMS BECOMING A DISTINCT POSSIBILITY IN THE NEXT FEW
HOURS BUT NOT NECESSARILY AFFECTING THE TAF SITES. SHOWERS HITTING
KDAY AND KILN WILL OCCUR EARLY AND LIKELY NOT REACH ANY STRENGTH
TO SEE THUNDERSTORMS TODAY. AT KCMH/KLCK THERE COULD STILL BE A
STORM POP AS TEMPERATURES THERE HAVE BUMPED TOWARDS 90 DEGREES AND
CONVECTION COULD STILL INITIATE WHERE SUNSHINE IS STILL ABUNDANT.
HIGHER CLOUDS AT 12-15KFT WILL PREVAIL TONIGHT AND INTO TOMORROW.
LOWER STRATOCU AND CU WILL DISSIPATE OVERNIGHT IN MOST SPOTS AND
IF SKIES CLEAR OUT A LITTLE IN THE 12-15KFT RANGE...FOG MAY
DEVELOP IN THE PREDAWN HOURS.
SHOWERS AND THUNDERSTORMS WILL LIKELY INITIATE TOMORROW IN THE
LATE MORNING AND MOVE INTO OHIO FROM INDIANA AND AFFECT WESTERN
TAF SITES LATE IN THE PERIOD.
OUTLOOK...SHOWERS MAY BRING MVFR CIGS MONDAY AND THUNDERSTORMS ARE
POSSIBLE TUESDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HATZOS
NEAR TERM...HATZOS
SHORT TERM...HATZOS
LONG TERM...HICKMAN
AVIATION...FRANKS
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
840 AM EDT SAT JUN 28 2014
.SYNOPSIS...
SOUTHERLY WINDS INCREASE MOISTURE TODAY. ROUNDS OF SHOWERS AND
THUNDERSTORMS THROUGH TUESDAY. FRONT WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
830 AM UPDATE...TWEAKED POP AND SKY GRIDS BASED ON CURRENT
TRENDS...MOISTURE A LITTLE SLOWER TO WORK INTO THE REGION THAN
PREVIOUSLY FORECAST. OTHERWISE...NO CHANGES NEEDED.
PREVIOUS DISCUSSION FOLLOWS...
SOME FAIRLY LARGE DIFFERENCES IN THE MODELS TODAY. NAM IS THE
SLOWEST BRINGING DEEPER MOISTURE INTO THE REGION WHILE THE GFS IS
THE FASTEST. RUC SEEMS TO REPRESENT A MIDDLE GROUND. LOOKING AT THE
VAD WINDS...BELIEVE THAT THE NAM MAY HAVE TOO WEAK OF A FLOW AT 700
MB...SO WILL LEAN MORE TOWARD THE RUC SOLUTION. THIS WOULD ALLOW FOR
THE BEST DEVELOPMENT OF THUNDERSTORMS ON THE SOUTHERN AND WESTERN
FLANKS. WILL RUN THE HIGHEST POPS IN THESE AREAS. MODELS INDICATE
THAT SHOWERS AND THUNDERSTORMS SHOULD CONTINUE SATURDAY NIGHT...SO
WILL KEEP SOME POPS THROUGHOUT THE NIGHT.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
WILL BE TRACKING A S/W TROF THAT WILL MAKE A RUN AT THE AREA FROM
THE W ON SUNDAY...DAMPENING OUT AS IT DOES SO. TROF AXIS SLOWLY
PUSHES THRU CWA SUNDAY NIGHT INTO MONDAY BUT WITH LOSS OF
HEATING...EXPECT A DECREASE OF COVERAGE SUNDAY NIGHT BEFORE RAMPING
BACK UP MONDAY ACROSS E ZONES. KEPT INHERITED HEAVY RAIN WORDING IN
STORMS WITH PWATS AROUND 2 INCHES AND GENERALLY WEAK FLOW...THINK
DOWNPOURS A GOOD POSSIBILITY AND WILL HAVE TO WATCH FOR ANY S TO N
TRAINING SUNDAY FOR WATER CONCERNS. WILL HAVE A MENTION OF WATER
CONCERNS IN HWO FOR SUNDAY. OVERALL THOUGH...AREA IS ON THE DRY SIDE
SO IT WOULD TAKE SLOW MOVERS WITH SOME TRAINING TO REALLY ALLOW A
FLOOD THREAT TO MATERIALIZE.
DRIER AIR IN THE MID LEVELS WORKS IN MONDAY NIGHT WITH PWATS
LOWERING. WITH NO TRIGGER...ELECTED TO GO POP FREE MONDAY NIGHT
EXCEPT ACROSS THE MOUNTAINS WHERE RESIDUAL SE FLOW MAY KEEP AN
ISOLATED SHRA THREAT GOING.
SOME CHANGES FOR TUESDAY AS GFS AND GEM HAVE SLOWED PROGRESSION OF
UPPER TROF AND ASSOCIATED COLD FRONT. THE NEW ECMWF HAS ALSO SLOWED
THINGS DOWN BUT NOT TO THE EXTENT OF THE OTHER TWO MODELS. AS
SUCH...HAVE STIFF ARMED HIGH POPS UNTIL LATE TUESDAY AFTERNOON AND
EVENING ACROSS W ZONES.
BLENDED IN INHERITED TEMPERATURES WITH LATEST ALLBLEND TOOL WITH
SOME INCORPORATION OF HIRES ARW EARLY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
NO MAJOR CHANGES IN OUR THINKING FROM YESTERDAY. A PSEUDO LULL IN
COVERAGE OF SHOWERS AND THUNDERSTORMS STILL FIGURED FOR OVERNIGHT
MONDAY NIGHT INTO EARLY TUESDAY...AS 12Z MODELS PUSH THE DEEPER
MOISTURE EAST OF THE MOUNTAIN COUNTIES AFTER 00Z TUESDAY.
AFTER THE WEAK AND SLUGGISH SUMMER FLOW OVER THE WEEKEND INTO
MONDAY...WINDS AT ALL LEVELS BEGINS TO INCREASE OVERNIGHT MONDAY
NIGHT.
STILL FIGURING ON ABOUT A 30 KNOT STEERING CURRENT FLOW ON TUESDAY.
FASTER MOVING STORMS ARE LIKELY. NOT THE BEST SUPPORT TUESDAY
AFTERNOON FROM THE 60 TO 70 MPH 300 MB JET MAX STILL LOCATED OVER
THE MIDWEST. 12Z GFS FORECAST SOUNDINGS STILL HAVE EL ABOUT 40 THSD
FT. CAN NOT RULE OUT SEVERE TO STRONG THUNDERSTORMS ON TUESDAY
AFTERNOON INTO TUESDAY EVENING.
WILL LEAVE CHANCE OF LIGHTER LEFTOVERS...SHOWERS/STORMS...ON
WEDNESDAY...FIGURING THE SURFACE FRONT STILL MOVING THROUGH. THIS
SHOULD SET UP US FOR DRIER AND FRESHER AIR THURSDAY...HOPING IT
HOLDS FOR INDEPENDENCE DAY TOO.
&&
.AVIATION /13Z SATURDAY THROUGH WEDNESDAY/...
SOME PATCHY FOG ACROSS SOUTHEAST OHIO AND NORTHERN WV WILL DISSIPATE
QUICKLY EARLY THIS MORNING. CUMULUS CLOUDS CAN BE EXPECTED TODAY
WITH SOME THUNDERSTORMS CAUSING RESTRICTIONS. SCATTERED
THUNDERSTORMS ARE EXPECTED TO CONTINUE SATURDAY NIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z SUNDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: TIMING OF SHOWERS AND THUNDERSTORMS TODAY AND
SATURDAY NIGHT COULD VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 11 12 13 14 15 16 17 18 19 20 21 22
EDT 1HRLY 07 08 09 10 11 12 13 14 15 16 17 18
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H L L H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY M L H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z SUNDAY...
IFR CONDITIONS POSSIBLE IN ROUNDS OF THUNDERSTORMS SATURDAY NIGHT INTO
WEDNESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KTB/RPY/30
NEAR TERM...RPY/SL
SHORT TERM...30
LONG TERM...KTB
AVIATION...RPY
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
613 AM EDT SAT JUN 28 2014
.SYNOPSIS...
SOUTHERLY WINDS INCREASE MOISTURE TODAY. ROUNDS OF SHOWERS AND
THUNDERSTORMS THROUGH TUESDAY. FRONT WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
SOME FAIRLY LARGE DIFFERENCES IN THE MODELS TODAY. NAM IS THE
SLOWEST BRINGING DEEPER MOISTURE INTO THE REGION WHILE THE GFS IS
THE FASTEST. RUC SEEMS TO REPRESENT A MIDDLE GROUND. LOOKING AT THE
VAD WINDS...BELIEVE THAT THE NAM MAY HAVE TOO WEAK OF A FLOW AT 700
MB...SO WILL LEAN MORE TOWARD THE RUC SOLUTION. THIS WOULD ALLOW FOR
THE BEST DEVELOPMENT OF THUNDERSTORMS ON THE SOUTHERN AND WESTERN
FLANKS. WILL RUN THE HIGHEST POPS IN THESE AREAS. MODELS INDICATE
THAT SHOWERS AND THUNDERSTORMS SHOULD CONTINUE SATURDAY NIGHT...SO
WILL KEEP SOME POPS THROUGHOUT THE NIGHT.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
WILL BE TRACKING A S/W TROF THAT WILL MAKE A RUN AT THE AREA FROM
THE W ON SUNDAY...DAMPENING OUT AS IT DOES SO. TROF AXIS SLOWLY
PUSHES THRU CWA SUNDAY NIGHT INTO MONDAY BUT WITH LOSS OF
HEATING...EXPECT A DECREASE OF COVERAGE SUNDAY NIGHT BEFORE RAMPING
BACK UP MONDAY ACROSS E ZONES. KEPT INHERITED HEAVY RAIN WORDING IN
STORMS WITH PWATS AROUND 2 INCHES AND GENERALLY WEAK FLOW...THINK
DOWNPOURS A GOOD POSSIBILITY AND WILL HAVE TO WATCH FOR ANY S TO N
TRAINING SUNDAY FOR WATER CONCERNS. WILL HAVE A MENTION OF WATER
CONCERNS IN HWO FOR SUNDAY. OVERALL THOUGH...AREA IS ON THE DRY SIDE
SO IT WOULD TAKE SLOW MOVERS WITH SOME TRAINING TO REALLY ALLOW A
FLOOD THREAT TO MATERIALIZE.
DRIER AIR IN THE MID LEVELS WORKS IN MONDAY NIGHT WITH PWATS
LOWERING. WITH NO TRIGGER...ELECTED TO GO POP FREE MONDAY NIGHT
EXCEPT ACROSS THE MOUNTAINS WHERE RESIDUAL SE FLOW MAY KEEP AN
ISOLATED SHRA THREAT GOING.
SOME CHANGES FOR TUESDAY AS GFS AND GEM HAVE SLOWED PROGRESSION OF
UPPER TROF AND ASSOCIATED COLD FRONT. THE NEW ECMWF HAS ALSO SLOWED
THINGS DOWN BUT NOT TO THE EXTENT OF THE OTHER TWO MODELS. AS
SUCH...HAVE STIFF ARMED HIGH POPS UNTIL LATE TUESDAY AFTERNOON AND
EVENING ACROSS W ZONES.
BLENDED IN INHERITED TEMPERATURES WITH LATEST ALLBLEND TOOL WITH
SOME INCORPORATION OF HIRES ARW EARLY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
NO MAJOR CHANGES IN OUR THINKING FROM YESTERDAY. A PSEUDO LULL IN
COVERAGE OF SHOWERS AND THUNDERSTORMS STILL FIGURED FOR OVERNIGHT
MONDAY NIGHT INTO EARLY TUESDAY...AS 12Z MODELS PUSH THE DEEPER
MOISTURE EAST OF THE MOUNTAIN COUNTIES AFTER 00Z TUESDAY.
AFTER THE WEAK AND SLUGGISH SUMMER FLOW OVER THE WEEKEND INTO
MONDAY...WINDS AT ALL LEVELS BEGINS TO INCREASE OVERNIGHT MONDAY
NIGHT.
STILL FIGURING ON ABOUT A 30 KNOT STEERING CURRENT FLOW ON TUESDAY.
FASTER MOVING STORMS ARE LIKELY. NOT THE BEST SUPPORT TUESDAY
AFTERNOON FROM THE 60 TO 70 MPH 300 MB JET MAX STILL LOCATED OVER
THE MIDWEST. 12Z GFS FORECAST SOUNDINGS STILL HAVE EL ABOUT 40 THSD
FT. CAN NOT RULE OUT SEVERE TO STRONG THUNDERSTORMS ON TUESDAY
AFTERNOON INTO TUESDAY EVENING.
WILL LEAVE CHANCE OF LIGHTER LEFTOVERS...SHOWERS/STORMS...ON
WEDNESDAY...FIGURING THE SURFACE FRONT STILL MOVING THROUGH. THIS
SHOULD SET UP US FOR DRIER AND FRESHER AIR THURSDAY...HOPING IT
HOLDS FOR INDEPENDENCE DAY TOO.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
SOME PATCHY FOG ACROSS SOUTHEAST OHIO AND NORTHERN WV WILL DISSIPATE
QUICKLY EARLY THIS MORNING. CUMULUS CLOUDS CAN BE EXPECTED TODAY
WITH SOME THUNDERSTORMS CAUSING RESTRICTIONS. SCATTERED
THUNDERSTORMS ARE EXPECTED TO CONTINUE SATURDAY NIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z SUNDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: TIMING OF SHOWERS AND THUNDERSTORMS TODAY AND
SATURDAY NIGHT COULD VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SAT 06/28/14
UTC 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19
EDT 1HRLY 04 05 06 07 08 09 10 11 12 13 14 15
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H L L L L L H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z SUNDAY...
IFR CONDITIONS POSSIBLE IN ROUNDS OF THUNDERSTORMS SATURDAY NIGHT INTO
WEDNESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KTB/RPY/30
NEAR TERM...RPY
SHORT TERM...30
LONG TERM...KTB
AVIATION...RPY
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
300 AM EDT SAT JUN 28 2014
.SYNOPSIS...
SOUTHERLY WINDS INCREASE MOISTURE TODAY. ROUNDS OF SHOWERS AND
THUNDERSTORMS THROUGH TUESDAY. FRONT WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
SOME FAIRLY LARGE DIFFERENCES IN THE MODELS TODAY. NAM IS THE
SLOWEST BRINGING DEEPER MOISTURE INTO THE REGION WHILE THE GFS IS
THE FASTEST. RUC SEEMS TO REPRESENT A MIDDLE GROUND. LOOKING AT THE
VAD WINDS...BELIEVE THAT THE NAM MAY HAVE TOO WEAK OF A FLOW AT 700
MB...SO WILL LEAN MORE TOWARD THE RUC SOLUTION. THIS WOULD ALLOW FOR
THE BEST DEVELOPMENT OF THUNDERSTORMS ON THE SOUTHERN AND WESTERN
FLANKS. WILL RUN THE HIGHEST POPS IN THESE AREAS. MODELS INDICATE
THAT SHOWERS AND THUNDERSTORMS SHOULD CONTINUE SATURDAY NIGHT...SO
WILL KEEP SOME POPS THROUGHOUT THE NIGHT.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
WILL BE TRACKING A S/W TROF THAT WILL MAKE A RUN AT THE AREA FROM
THE W ON SUNDAY...DAMPENING OUT AS IT DOES SO. TROF AXIS SLOWLY
PUSHES THRU CWA SUNDAY NIGHT INTO MONDAY BUT WITH LOSS OF
HEATING...EXPECT A DECREASE OF COVERAGE SUNDAY NIGHT BEFORE RAMPING
BACK UP MONDAY ACROSS E ZONES. KEPT INHERITED HEAVY RAIN WORDING IN
STORMS WITH PWATS AROUND 2 INCHES AND GENERALLY WEAK FLOW...THINK
DOWNPOURS A GOOD POSSIBILITY AND WILL HAVE TO WATCH FOR ANY S TO N
TRAINING SUNDAY FOR WATER CONCERNS. WILL HAVE A MENTION OF WATER
CONCERNS IN HWO FOR SUNDAY. OVERALL THOUGH...AREA IS ON THE DRY SIDE
SO IT WOULD TAKE SLOW MOVERS WITH SOME TRAINING TO REALLY ALLOW A
FLOOD THREAT TO MATERIALIZE.
DRIER AIR IN THE MID LEVELS WORKS IN MONDAY NIGHT WITH PWATS
LOWERING. WITH NO TRIGGER...ELECTED TO GO POP FREE MONDAY NIGHT
EXCEPT ACROSS THE MOUNTAINS WHERE RESIDUAL SE FLOW MAY KEEP AN
ISOLATED SHRA THREAT GOING.
SOME CHANGES FOR TUESDAY AS GFS AND GEM HAVE SLOWED PROGRESSION OF
UPPER TROF AND ASSOCIATED COLD FRONT. THE NEW ECMWF HAS ALSO SLOWED
THINGS DOWN BUT NOT TO THE EXTENT OF THE OTHER TWO MODELS. AS
SUCH...HAVE STIFF ARMED HIGH POPS UNTIL LATE TUESDAY AFTERNOON AND
EVENING ACROSS W ZONES.
BLENDED IN INHERITED TEMPERATURES WITH LATEST ALLBLEND TOOL WITH
SOME INCORPORATION OF HIRES ARW EARLY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
NO MAJOR CHANGES IN OUR THINKING FROM YESTERDAY. A PSEUDO LULL IN
COVERAGE OF SHOWERS AND THUNDERSTORMS STILL FIGURED FOR OVERNIGHT
MONDAY NIGHT INTO EARLY TUESDAY...AS 12Z MODELS PUSH THE DEEPER
MOISTURE EAST OF THE MOUNTAIN COUNTIES AFTER 00Z TUESDAY.
AFTER THE WEAK AND SLUGGISH SUMMER FLOW OVER THE WEEKEND INTO
MONDAY...WINDS AT ALL LEVELS BEGINS TO INCREASE OVERNIGHT MONDAY
NIGHT.
STILL FIGURING ON ABOUT A 30 KNOT STEERING CURRENT FLOW ON TUESDAY.
FASTER MOVING STORMS ARE LIKELY. NOT THE BEST SUPPORT TUESDAY
AFTERNOON FROM THE 60 TO 70 MPH 300 MB JET MAX STILL LOCATED OVER
THE MIDWEST. 12Z GFS FORECAST SOUNDINGS STILL HAVE EL ABOUT 40 THSD
FT. CAN NOT RULE OUT SEVERE TO STRONG THUNDERSTORMS ON TUESDAY
AFTERNOON INTO TUESDAY EVENING.
WILL LEAVE CHANCE OF LIGHTER LEFTOVERS...SHOWERS/STORMS...ON
WEDNESDAY...FIGURING THE SURFACE FRONT STILL MOVING THROUGH. THIS
SHOULD SET UP US FOR DRIER AND FRESHER AIR THURSDAY...HOPING IT
HOLDS FOR INDEPENDENCE DAY TOO.
&&
.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
SOME LOW LEVEL WINDS EARLY THIS MORNING WILL PREVENT DENSE
FOG...ALTHOUGH SOME MVFR VALLEY FOG IS POSSIBLE IN SOUTHEAST OHIO
AND NORTHERN WV. CUMULUS CLOUDS CAN BE EXPECTED TODAY WITH SOME
THUNDERSTORMS CAUSING RESTRICTIONS. SCATTERED THUNDERSTORMS ARE
EXPECTED TO CONTINUE SATURDAY NIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z SUNDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF VALLEY FOG EARLY THIS
MORNING COULD VARY. TIMING OF SHOWERS AND THUNDERSTORMS TODAY AND
SATURDAY NIGHT COULD VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SAT 06/28/14
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EDT 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H L L L L L H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 06Z SUNDAY...
IFR CONDITIONS POSSIBLE IN ROUNDS OF THUNDERSTORMS SATURDAY NIGHT INTO
WEDNESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KTB/RPY/30
NEAR TERM...RPY
SHORT TERM...30
LONG TERM...KTB
AVIATION...RPY
AREA FORECAST DISCUSSION
NWS TULSA OK
1226 PM CDT SAT JUN 28 2014
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
CLUSTER OF SHOWER/THUNDERSTORMS WILL MOVE INTO NE OK TAF SITES AFTER
18Z. THE STRONGER STORMS WILL LIKELY PRODUCE IFR CONDITIONS WITH
BRIEF HEAVY RAINFALL. THUNDERSTORM ACTIVITY IS EXPECTED TO SHIFT
INTO NORTHWEST ARKANSAS BY LATE AFTERNOON/EVENING. SCT/BKN LOW
CLOUDS SHOULD REDEVELOP AGAIN LATE TONIGHT...HOWEVER DID NOT
FORECAST AS LOW OF CEILINGS AS CURRENT MAV/MET GUIDANCE...WHICH
HAS BEEN TOO PESSIMISTIC THE LAST FEW DAYS.
&&
.PREV DISCUSSION... /ISSUED 1059 AM CDT SAT JUN 28 2014/
..UPDATE...
DISCUSSION...
STRONG/ISOLATED SEVERE THUNDERSTORM COMPLEX CONTINUES EASTWARD
THIS MORNING ACROSS NORTH CENTRAL OKLAHOMA. AHEAD OF ACTIVITY...
MOIST/UNSTABLE AIR-MASS REMAINS IN PLACE WITH MLCAPE RUNNING INTO
THE 1500-2000 J/KG RANGE. STRONGER FORCING IN ASSOCIATION WITH
UPPER WAVE LIFTING NORTHEAST INTO THE CENTRAL PLAINS. DEEP LAYER
SHEAR WILL BE SOMEWHAT MARGINAL AS THUNDERSTORM COMPLEX PUSHES
EASTWARD THIS AFTERNOON. BUT...AS SURFACE HEATING CONTINUES...COULD
STILL SEE THE THREAT FOR STRONG TO MARGINALLY SEVERE STORMS AS
CONVECTIVE LINE MOVES THROUGH NORTHEAST OKLAHOMA. THIS SCENARIO IS
IN LINE WITH WITH THE LATEST LOCAL WRF AND HRRR RUNS. UPDATE SENT
PREVIOUSLY TO REFLECT CURRENT THINKING...HOWEVER WILL LIKELY TWEAK
TIMING OF POPS INTO THIS AFTERNOON AS TRENDS BECOME MORE CERTAIN.
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
AVIATION...12
AREA FORECAST DISCUSSION
NWS TULSA OK
1059 AM CDT SAT JUN 28 2014
...UPDATE...
.DISCUSSION...
STRONG/ISOLATED SEVERE THUNDERSTORM COMPLEX CONTINUES EASTWARD
THIS MORNING ACROSS NORTH CENTRAL OKLAHOMA. AHEAD OF ACTIVITY...
MOIST/UNSTABLE AIR-MASS REMAINS IN PLACE WITH MLCAPE RUNNING INTO
THE 1500-2000 J/KG RANGE. STRONGER FORCING IN ASSOCIATION WITH
UPPER WAVE LIFTING NORTHEAST INTO THE CENTRAL PLAINS. DEEP LAYER
SHEAR WILL BE SOMEWHAT MARGINAL AS THUNDERSTORM COMPLEX PUSHES
EASTWARD THIS AFTERNOON. BUT...AS SURFACE HEATING CONTINUES...COULD
STILL SEE THE THREAT FOR STRONG TO MARGINALLY SEVERE STORMS AS
CONVECTIVE LINE MOVES THROUGH NORTHEAST OKLAHOMA. THIS SCENARIO IS
IN LINE WITH WITH THE LATEST LOCAL WRF AND HRRR RUNS. UPDATE SENT
PREVIOUSLY TO REFLECT CURRENT THINKING...HOWEVER WILL LIKELY TWEAK
TIMING OF POPS INTO THIS AFTERNOON AS TRENDS BECOME MORE CERTAIN.
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
SHORT TERM...12
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1035 PM EDT SUN JUN 29 2014
.SYNOPSIS...
OFFSHORE HIGH AND LOW PRESSURE SYSTEMS WILL CONTINUE TO BRING IN
HIGH AMOUNTS OF ATLANTIC MOISTURE...POSSIBLY PRODUCING LOCALIZED
FLOODING EVENTS THIS EVENING. THE WEATHER PATTERN WILL CHANGE ON
MONDAY WITH A TREND BACK TO A TYPICAL SUMMERTIME REGIME THROUGH THE
END OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
AT 1030 PM EDT SUNDAY... CONVECTIVE PRECIPITATION AND TRAILING AREAS
OF LIGHT RAIN ARE DIMINISHING AS THEY MOVE INTO EASTERN PORTION OF
THE CWA. ACCORDINGLY... POPS HAVE BEEN INCREASED A BIT IN THE EAST
AND DECREASED SUBSTANTIALLY IN THE WEST. NEARLY ALL PRECIPITATION
SHOULD END BY 2 AM.
PREVIOUS DISCUSSIONS...
AT 730 PM... NARROW LINE OF CONVECTIVE RAIN MOVING INTO CENTRAL
PORTION OF THE CWA HAS LEFT BEHIND AREAS OF RAIN IN THE WEST. RADAR
TRENDS INDICATE THE PRECIPITATION IN THE WEST IS ON THE WANE... BUT
CONVECTIVE LINE IS MAINTAINING ITS STRENGTH. THE CONVECTIVE
PRECIPITATION SHOULD DIMINISH AS IT MOVES INTO EASTERN CWA. THE
CAPE... LI... AND K INDEX ALL SHOW A TIGHT DECREASING GRADIENT OVER
THE EASTERN ZONES. EXPECT THE ONGOING CONVECTION WILL WEAKEN AS IT
APPROACHES THAT AREA. EARLY EVENING UPDATE HOLDS ON TO HIGH POPS IN
THE WEST TAILING OFF TOWARD THE EAST. WILL MONITOR WITH INTENTION OF
INCREASING POPS IN THE EAST IF EXPECTED DISSIPATION DOES NOT OCCUR.
AT 630 PM EDT SUNDAY... PREVIOUSLY DISCUSSED WEATHER AND POPS STILL
APPLY BUT POPS HAVE BEEN INCREASED OVER WESTERN ZONES TO ACCOUNT FOR
EXPANSIVE LIGHT TO MODERATE RAIN FOLLOWING CONVECTIVE STORMS.
LOCALLY HEAVY RAIN WILL BE A CONCERN THROUGH THE EVENING ALONG AND
NEAR THE BLUE RIDGE ESCARPMENT AND INTO THE FOOTHILLS.
AT 430 PM EDT SUNDAY... FAIRLY EXTENSIVE AREA OF CONVECTIVE STORMS
AND ASSOCIATED AREAS OF LIGHT TO MODERATE RAIN WERE MOVING INTO TO
THE WESTERN PORTION OF THE FORECAST AREA LATE THIS AFTERNOON.
CONVECTION IS FEEDING ON CAPE VALUES GREATER THAN 1500 J/KG IN A
TONGUE OF HIGH ENERGY EXTENDING FROM SOUTHEAST GEORGIA INTO WESTERN
UPSTATE SOUTH CAROLINA. HAVE INCREASED POPS OVER WESTERN ZONES TO
ACCOUNT FOR THE LATE AFTERNOON AND EVENING STORMS. HRRR HAS A
REASONABLE... BUT FAR FROM EXACT... DEPICTION OF THE CONVECTION. THE
HRRR TREND FITS THE FORECAST CAPE FIELD WHICH FOLLOWS A TYPICAL
DIURNAL DOWNWARD TREND AROUND SUNSET AND DURING THE SUBSEQUENT
HOURS. WILL LOWER POPS ACCORDINGLY DURING THE EVENING. HMT-SOUTHEAST
PROFILERS IN THE FOOTHILLS INDICATE A VERY WEAK UPSLOPE FLOW NEAR
THE SURFACE BUT LIGHT WINDS BECOME NEARLY PARALLEL TO THE TERRAIN
ABOVE APPROXIMATELY 3K FEET. CAPE VALUES REMAIN QUITE LOW OVER
EASTERN ZONES AND SATELLITE IMAGERY SHOWS LITTLE IN THE WAY OF
CONVECTIVE CLOUDS OTHER THAN FAIR WEATHER CUMULUS.
AT 230 PM EDT SUNDAY...THE EAST COAST UPPER RIDGE WILL DEAMPLIFY
TONIGHT AND MONDAY...LEADING TO A ZONAL FLOW OVER THE SOUTHERN
APPALACHIANS. A SLOW MOVING UPPER LEVEL IMPULSE IS EXPECTED TO
APPROACH THE SOUTHERN APPALACHIANS THIS EVENING..CROSSING THE
MOUNTAINS AROUND DAYBREAK...AND MOVING ACROSS THE FOOTHILLS AND
PIEDMONT ON MONDAY.
MEANWHILE...A STATIONARY FRONT WILL SLOWLY WEAKEN OVER THE SAVANNAH
RIVER VALLEY...AND HIGH PRESSURE WILL DRIFT OFF THE EAST COAST. A
SURFACE LOW DRIFTING SLOWLY SOUTH OFF THE FL COAST IS BEING
MONITORED BY NHC FOR SIGNS OF TROPICAL DEVELOPMENT. DEEP MOISTURE
REMAINS BANKED UP AGAINST THE APPALACHIANS.
AFTERNOON CONVECTION IS EXPECTED TO LINGER INTO THE EVENING...WITH A
GRADUAL SHIFT FROM THE BLUE RIDGE EAST IN A WEAK STEERING FLOW.
HEAVY RAINFALL WILL BE POSSIBLE WITH SLOW MOVING CELLS...PRESENTING
THE POSSIBILITY OF LOCALIZED FLOODING. WITH ONLY MODEST INSTABILITY
PRESENT...SEVERE WEATHER IS NOT EXPECTED OF GREAT CONCERN. MINIMUM
TEMPERATURES WILL RUN SLIGHTLY ABOVE CLIMATOLOGY IN ABOVE NORMAL
MOISTURE. DAYBREAK FOG WILL BE MOST LIKELY IN MOUNTAIN VALLEYS...
AND RAIN SOAKED AREAS IN THE LEE OF THE MOUNTAINS.
INSTABILITY IS ONLY EXPECTED TO BE SLIGHTLY GREATER ON MONDAY...
SLIGHTLY DRIER AIR ALOFT WILL BE AVAILABLE FOR EVAPORATIVE COOLING.
ALTHOUGH MOISTURE APPEARS SLIGHTLY MORE LIMITED IN MODEL
SOUNDINGS...STEERING FLOW REMAINS WEAK...AND HEAVY RAIN STILL
REMAINS A CONCERN WITH SLOW MOVING CONVECTION PROVOKED BY THE UPPER
LEVEL IMPULSE. DESPITE LOWER HEIGHTS ALOFT WITH THE BREAKDOWN OF
THE UPPER RIDGE...SURFACE TEMPERATURES ARE EXPECTED TO BE WARMER AS
THE AIR MASS MODIFIES AND SW FLOW ENSUES IN THE WAKE OF THE SURFACE
HIGH.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
AT 230 PM EDT SUNDAY. FOR THE PERIOD MONDAY NIGHT THROUGH WEDNESDAY.
A S/W WILL BE CROSSING OUR FORECAST AREA MONDAY NIGHT...WHILE HAVING
THE OPPORTUNITY TO INTERCEPT MOISTURE AND INSTABILITY FROM THOSE
LOCATIONS THAT DID NOT HAVE THE ATMOSPHERE WORKED OVER DURING THE
DAYLIGHT HOURS MONDAY. WE WILL THEN ALLOW POPS TO LOWER DURING THE
WEE HOURS MONDAY/PREDAWN TUESDAY...AS THE S/W PASSES BY AND
SUBSIDENCE PREVAILS.
ON TUESDAY WE ARE CAUGHT IN THE MIDDLE OF DUAL AMPLIFYING TROFS TO
OUR NORTH AND NORTHWEST...AND THE SYSTEM OFF THE EAST COAST OF
FLORIDA. IT APPEARS WE MAY BE IN A CONVECTIVE LULL WITH INHIBITION
NOTED ON VARIOUS SOUNDINGS...EXCEPT IN THE MOUNTAINS. THEREFORE HAVE
ONLY A SLIGHT CHANCE POPS...ALBEIT A TAD HIGHER IN THE
MOUNTAINS...WHERE SOME MINOR LOW LEVEL CONVERGENCE WAS NOTED...AND
SWLY UPSLOPE FLOW PREVAILS. H85 THERMAL PATTERN SUGGESTS TEMPS ON
THE WAY UP TUESDAY...AND THIS IS SUPPORTED BY NEARLY ALL GUIDE
TEMPERATURE PACKAGES.
ANY ISOLATED CONVECTION TUESDAY EVENING WILL END WITH LOSS OF
HEATING FOLLOWED BY FAIR SKIES.
A BIT MORE INTERESTING WEDNESDAY WITH LESS CONVECTIVE INHIBITION...
CONSIDERABLE "FAT" LOOKING CAPE...AND SOME WEAK BOUNDARY DRIFTING
INTO THE REGION FROM THE WEST. THEREFORE HAVE EDGED POPS UPWARD INTO
THE CHANCE CATEGORY...WITH A VERY WARM AND JUICY AIRMASS STILL IN
PLACE.
MEANWHILE...APPARENT TEMPERATURES ON BOTH TUESDAY AND WEDNESDAY WILL
RANGE FROM 95 TO 100 DEGREES...IN THE WESTERN PIEDMONT OF NC/UPSTATE
SC AND PARTS OF NE GEORGIA.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 200 PM EDT SUNDAY...MODEL AGREEMENT STILL VERY GOOD ON THE
DEVELOPMENT OF HIGH AMPLITUDE PROGRESSIVE UPPER LEVEL PATTERN FOR
THE MEDIUM RANGE. A SLOW-MOVING TROF AXIS SHUD ENTER THE GREAT LAKES
TO THE TN VALLEY BY EARLY THURSDAY...THEN GRADUALLY CROSS THE
APPALACHIANS AND EAST COAST FRIDAY THRU SATURDAY. THIS TROF IS
EXPECTED TO PICK UP A TROPICAL DISTURBANCE (WHICH MAY BE A TROPICAL
STORM OR HURRICANE BY THEN)...FROM THE FL ATLANTIC COAST REGION. THE
LATEST NHC FCST IS CLOSE TO THE 00Z ECMWF...WITH A LIKELY TROPICAL
STORM LIFTING NE JUST OFFSHORE...AHEAD OF A COLD FRONT THAT IS
EXPECTED TO CROSS OUR AREA FROM THE WEST ON THURSDAY. SO AT THIS
TIME...STILL NOT EXPECTING ANY DIRECT IMPACT FROM THAT SYSTEM. AS
FOR THE FRONT ITSELF...GUIDANCE SHOWS ENHANCED CAPE IN THE WARM
SECTOR ALONG AND AHEAD OF THE BNDRY...WITH DECENT QPF RESPONSE.
TAKING A BLEND OF WPC GRIDS AND THE MODEL CONSENSUS...POPS WERE
BUMPED UP TO HIGH-END CHC TO LOW-LIKELY FOR THURSDAY ACRS PRETTY
MUCH THE ENTIRE CWFA.
SOME DRIER AIR AND FALLING THICKNESSES SHUD RESULT IN ONLY ISOLD TO
WIDELY SCATTERED DIURNALLY-DRIVEN CONVECTION FOR FRIDAY AND
SATURDAY...WITH TEMPS BACK TO NEAR OR EVEN A DEG OR TWO BELOW NORMAL
FOR NEXT WEEKEND.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
AT KCLT...SCATTERED TO OCCASIONALLY BROKEN CLOUDS NEAR 4K AND 10K FT
EXPECTED OVERNIGHT. LINE OF SHOWERS AND THUNDERSTORMS THAT WAS
OVER WESTERN CAROLINAS SUNDAY EVENING HAS WEAKENED STEADILY WHILE
MOVING EASTWARD. RAIN SHOWERS WITH VISIBILITY NEAR 5 MILES WILL BE
IN THE VICINITY OF THE AERODROME UNTIL APPROXIMATELY 06Z AS THE
WEAKENING PRECIPITATION CROSSES THE AREA. RAIN CAN CONTRIBUTE TO FOG
AND VISIBILITY 4 TO 6 MILES BETWEEN 06Z AND 12Z. AFTER SUNRISE
MONDAY... UNRESTRICTED VISIBILITY AND SCATTERED CUMULUS WITH BASES
NEAR 4K FT BECOMING OCCASIONALLY BROKEN AFTER 18Z. ISOLATED TO
SCATTERED THUNDERSTORMS POSSIBLE DURING MID AND LATE AFTERNOON.
SURFACE WINDS OVERNIGHT WILL FAVOR A SOUTHEAST DIRECTION... BUT THEY
ARE LIKELY TO BE LIGHT AND VARIABLE AT TIMES.
ELSEWHERE...SCATTERED TO BROKEN LAYERS NEAR 4K AND 10K FT. AREAS OF
FOG DURING THE EARLY MORNING HOURS WILL REDUCE VISIBILITY TO 1 TO 3
MILES AND BE ACCOMPANIED BY CEILING BELOW 1K FT. AFTER SUNRISE...
VISIBILITY WILL BECOME UNRESTRICTED AND SCATTERED TO BROKEN CUMULUS
WITH BASES NEAR 4K FT WILL DEVELOP. AFTER 18Z... EXPECT ISOLATED TO
SCATTERED THUNDERSTORMS... MOST NUMEROUS VICINTIY KAVL.
OUTLOOK...A RETURN TO MORE TYPICAL SUMMERTIME CONDITIONS IS EXPECTED
THROUGH THE WEEK...WITH MORNING CIG AND VSBY RESTRICTIONS IN FOG
MOST LIKELY IN THE MOUNTAINS.
CONFIDENCE TABLE...
02-08Z 08-14Z 14-20Z 20-02Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 99% HIGH 90% HIGH 100% HIGH 100%
KAVL MED 72% HIGH 90% MED 79% LOW 58%
KHKY HIGH 100% HIGH 82% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 95% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 81% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...ARK
NEAR TERM...LGL
SHORT TERM...TS
LONG TERM...ARK
AVIATION...LGL
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
801 PM EDT SUN JUN 29 2014
.SYNOPSIS...
OFFSHORE HIGH AND LOW PRESSURE SYSTEMS WILL CONTINUE TO BRING IN
HIGH AMOUNTS OF ATLANTIC MOISTURE...POSSIBLY PRODUCING LOCALIZED
FLOODING EVENTS THIS EVENING. THE WEATHER PATTERN WILL CHANGE ON
MONDAY WITH A TREND BACK TO A TYPICAL SUMMERTIME REGIME THROUGH THE
END OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
AT 730 PM EDT SUNDAY... NARROW LINE OF CONVECTIVE PRECIPITATION
MOVING INTO CENTRAL PORTION OF THE CWA HAS LEFT BEHIND AREAS OF
RAIN IN THE WEST. RADAR TRENDS INDICATE THE PRECIPITATION IN THE
WEST IS ON THE WANE... BUT CONVECTIVE LINE IS MAINTAINING ITS
STRENGTH. THE CONVECTIVE PRECIPITATION SHOULD DIMINISH AS IT MOVES
INTO EASTERN CWA. THE CAPE... LI... AND K INDEX ALL SHOW A TIGHT
DECREASING GRADIENT OVER THE EASTERN ZONES. EXPECT THE ONGOING
CONVECTION WILL WEAKEN AS IT APPROACHES THAT AREA. EARLY EVENING
UPDATE HOLDS ON TO HIGH POPS IN THE WEST TAILING OFF TOWARD THE
EAST. WILL MONITOR WITH INTENTION OF INCREASING POPS IN THE EAST
IF EXPECTED DISSIPATION DOES NOT OCCUR.
PREVIOUS DISCUSSIONS...
AT 630 PM EDT SUNDAY... PREVIOUSLY DISCUSSED WEATHER AND POPS STILL
APPLY BUT POPS HAVE BEEN INCREASED OVER WESTERN ZONES TO ACCOUNT FOR
EXPANSIVE LIGHT TO MODERATE RAIN FOLLOWING CONVECTIVE STORMS.
LOCALLY HEAVY RAIN WILL BE A CONCERN THROUGH THE EVENING ALONG AND
NEAR THE BLUE RIDGE ESCARPMENT AND INTO THE FOOTHILLS.
AT 430 PM EDT SUNDAY... FAIRLY EXTENSIVE AREA OF CONVECTIVE STORMS
AND ASSOCIATED AREAS OF LIGHT TO MODERATE RAIN WERE MOVING INTO TO
THE WESTERN PORTION OF THE FORECAST AREA LATE THIS AFTERNOON.
CONVECTION IS FEEDING ON CAPE VALUES GREATER THAN 1500 J/KG IN A
TONGUE OF HIGH ENERGY EXTENDING FROM SOUTHEAST GEORGIA INTO WESTERN
UPSTATE SOUTH CAROLINA. HAVE INCREASED POPS OVER WESTERN ZONES TO
ACCOUNT FOR THE LATE AFTERNOON AND EVENING STORMS. HRRR HAS A
REASONABLE... BUT FAR FROM EXACT... DEPICTION OF THE CONVECTION. THE
HRRR TREND FITS THE FORECAST CAPE FIELD WHICH FOLLOWS A TYPICAL
DIURNAL DOWNWARD TREND AROUND SUNSET AND DURING THE SUBSEQUENT
HOURS. WILL LOWER POPS ACCORDINGLY DURING THE EVENING. HMT-SOUTHEAST
PROFILERS IN THE FOOTHILLS INDICATE A VERY WEAK UPSLOPE FLOW NEAR
THE SURFACE BUT LIGHT WINDS BECOME NEARLY PARALLEL TO THE TERRAIN
ABOVE APPROXIMATELY 3K FEET. CAPE VALUES REMAIN QUITE LOW OVER
EASTERN ZONES AND SATELLITE IMAGERY SHOWS LITTLE IN THE WAY OF
CONVECTIVE CLOUDS OTHER THAN FAIR WEATHER CUMULUS.
AT 230 PM EDT SUNDAY...THE EAST COAST UPPER RIDGE WILL DEAMPLIFY
TONIGHT AND MONDAY...LEADING TO A ZONAL FLOW OVER THE SOUTHERN
APPALACHIANS. A SLOW MOVING UPPER LEVEL IMPULSE IS EXPECTED TO
APPROACH THE SOUTHERN APPALACHIANS THIS EVENING..CROSSING THE
MOUNTAINS AROUND DAYBREAK...AND MOVING ACROSS THE FOOTHILLS AND
PIEDMONT ON MONDAY.
MEANWHILE...A STATIONARY FRONT WILL SLOWLY WEAKEN OVER THE SAVANNAH
RIVER VALLEY...AND HIGH PRESSURE WILL DRIFT OFF THE EAST COAST. A
SURFACE LOW DRIFTING SLOWLY SOUTH OFF THE FL COAST IS BEING
MONITORED BY NHC FOR SIGNS OF TROPICAL DEVELOPMENT. DEEP MOISTURE
REMAINS BANKED UP AGAINST THE APPALACHIANS.
AFTERNOON CONVECTION IS EXPECTED TO LINGER INTO THE EVENING...WITH A
GRADUAL SHIFT FROM THE BLUE RIDGE EAST IN A WEAK STEERING FLOW.
HEAVY RAINFALL WILL BE POSSIBLE WITH SLOW MOVING CELLS...PRESENTING
THE POSSIBILITY OF LOCALIZED FLOODING. WITH ONLY MODEST INSTABILITY
PRESENT...SEVERE WEATHER IS NOT EXPECTED OF GREAT CONCERN. MINIMUM
TEMPERATURES WILL RUN SLIGHTLY ABOVE CLIMATOLOGY IN ABOVE NORMAL
MOISTURE. DAYBREAK FOG WILL BE MOST LIKELY IN MOUNTAIN VALLEYS...
AND RAIN SOAKED AREAS IN THE LEE OF THE MOUNTAINS.
INSTABILITY IS ONLY EXPECTED TO BE SLIGHTLY GREATER ON MONDAY...
SLIGHTLY DRIER AIR ALOFT WILL BE AVAILABLE FOR EVAPORATIVE COOLING.
ALTHOUGH MOISTURE APPEARS SLIGHTLY MORE LIMITED IN MODEL
SOUNDINGS...STEERING FLOW REMAINS WEAK...AND HEAVY RAIN STILL
REMAINS A CONCERN WITH SLOW MOVING CONVECTION PROVOKED BY THE UPPER
LEVEL IMPULSE. DESPITE LOWER HEIGHTS ALOFT WITH THE BREAKDOWN OF
THE UPPER RIDGE...SURFACE TEMPERATURES ARE EXPECTED TO BE WARMER AS
THE AIR MASS MODIFIES AND SW FLOW ENSUES IN THE WAKE OF THE SURFACE
HIGH.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
AT 230 PM EDT SUNDAY. FOR THE PERIOD MONDAY NIGHT THROUGH WEDNESDAY.
A S/W WILL BE CROSSING OUR FORECAST AREA MONDAY NIGHT...WHILE HAVING
THE OPPORTUNITY TO INTERCEPT MOISTURE AND INSTABILITY FROM THOSE
LOCATIONS THAT DID NOT HAVE THE ATMOSPHERE WORKED OVER DURING THE
DAYLIGHT HOURS MONDAY. WE WILL THEN ALLOW POPS TO LOWER DURING THE
WEE HOURS MONDAY/PREDAWN TUESDAY...AS THE S/W PASSES BY AND
SUBSIDENCE PREVAILS.
ON TUESDAY WE ARE CAUGHT IN THE MIDDLE OF DUAL AMPLIFYING TROFS TO
OUR NORTH AND NORTHWEST...AND THE SYSTEM OFF THE EAST COAST OF
FLORIDA. IT APPEARS WE MAY BE IN A CONVECTIVE LULL WITH INHIBITION
NOTED ON VARIOUS SOUNDINGS...EXCEPT IN THE MOUNTAINS. THEREFORE HAVE
ONLY A SLIGHT CHANCE POPS...ALBEIT A TAD HIGHER IN THE
MOUNTAINS...WHERE SOME MINOR LOW LEVEL CONVERGENCE WAS NOTED...AND
SWLY UPSLOPE FLOW PREVAILS. H85 THERMAL PATTERN SUGGESTS TEMPS ON
THE WAY UP TUESDAY...AND THIS IS SUPPORTED BY NEARLY ALL GUIDE
TEMPERATURE PACKAGES.
ANY ISOLATED CONVECTION TUESDAY EVENING WILL END WITH LOSS OF
HEATING FOLLOWED BY FAIR SKIES.
A BIT MORE INTERESTING WEDNESDAY WITH LESS CONVECTIVE INHIBITION...
CONSIDERABLE "FAT" LOOKING CAPE...AND SOME WEAK BOUNDARY DRIFTING
INTO THE REGION FROM THE WEST. THEREFORE HAVE EDGED POPS UPWARD INTO
THE CHANCE CATEGORY...WITH A VERY WARM AND JUICY AIRMASS STILL IN
PLACE.
MEANWHILE...APPARENT TEMPERATURES ON BOTH TUESDAY AND WEDNESDAY WILL
RANGE FROM 95 TO 100 DEGREES...IN THE WESTERN PIEDMONT OF NC/UPSTATE
SC AND PARTS OF NE GEORGIA.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 200 PM EDT SUNDAY...MODEL AGREEMENT STILL VERY GOOD ON THE
DEVELOPMENT OF HIGH AMPLITUDE PROGRESSIVE UPPER LEVEL PATTERN FOR
THE MEDIUM RANGE. A SLOW-MOVING TROF AXIS SHUD ENTER THE GREAT LAKES
TO THE TN VALLEY BY EARLY THURSDAY...THEN GRADUALLY CROSS THE
APPALACHIANS AND EAST COAST FRIDAY THRU SATURDAY. THIS TROF IS
EXPECTED TO PICK UP A TROPICAL DISTURBANCE (WHICH MAY BE A TROPICAL
STORM OR HURRICANE BY THEN)...FROM THE FL ATLANTIC COAST REGION. THE
LATEST NHC FCST IS CLOSE TO THE 00Z ECMWF...WITH A LIKELY TROPICAL
STORM LIFTING NE JUST OFFSHORE...AHEAD OF A COLD FRONT THAT IS
EXPECTED TO CROSS OUR AREA FROM THE WEST ON THURSDAY. SO AT THIS
TIME...STILL NOT EXPECTING ANY DIRECT IMPACT FROM THAT SYSTEM. AS
FOR THE FRONT ITSELF...GUIDANCE SHOWS ENHANCED CAPE IN THE WARM
SECTOR ALONG AND AHEAD OF THE BNDRY...WITH DECENT QPF RESPONSE.
TAKING A BLEND OF WPC GRIDS AND THE MODEL CONSENSUS...POPS WERE
BUMPED UP TO HIGH-END CHC TO LOW-LIKELY FOR THURSDAY ACRS PRETTY
MUCH THE ENTIRE CWFA.
SOME DRIER AIR AND FALLING THICKNESSES SHUD RESULT IN ONLY ISOLD TO
WIDELY SCATTERED DIURNALLY-DRIVEN CONVECTION FOR FRIDAY AND
SATURDAY...WITH TEMPS BACK TO NEAR OR EVEN A DEG OR TWO BELOW NORMAL
FOR NEXT WEEKEND.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
AT KCLT...SCATTERED TO OCCASIONALLY BROKEN CLOUDS NEAR 5K AND 10 FT
EXPECTED THIS EVENING. LINE OF SHOWERS AND THUNDERSTORMS OVER
WESTERN CAROLINAS MOVING TOWARD THE EAST COULD RESULT IN LOWER
CONDITIONS LATER... BUT A WEAKENING IS EXPECTED BEFORE REACHING
KCLT. WILL AMEND IF NECESSARY. VISIBILITY WILL REMAIN UNRESTRICTED
UNLESS PRECIPITATION REACHES THE AIRFIELD. OVERNIGHT NO SIGNIFICANT
CLOUDS OR WEATHER EXPECTED... ALTHOUGH FOG WILL BE A POSSIBILITY IF
RAIN REACHES THE TERMINAL AREA. AFTER SUNRISE MONDAY... UNRESTRICTED
VISIBILITY AND SCATTERED CUMULUS WITH BASES NEAR 4K FT BECOMING
OCCASIONALLY BROKEN AFTER 18Z. SURFACE WINDS OVERNIGHT WILL FAVOR A
SOUTHEAST DIRECTION... BUT THEY ARE LIKELY TO BE LIGHT AND VARIABLE
AT TIMES.
ELSEWHERE...CEILING AND VISIBILITY RESTRICTIONS WILL PERSIST IN
SHOWERS AND THUNDERSTORMS MOVING EAST OF KAVL AND KGSP. ISOLATED
SHOWERS OR THUNDERSTORMS POSSIBLE OVERNIGHT... BUT TERMINALS THAT
RECEIVED RAINFALL ARE LIKELY TO EXPERIENCE FOG DURING THE EARLY
MORNING HOURS. AFTER SUNRISE... VISIBILITY WILL BECOME UNRESTRICTED
AND SCATTERED TO BROKEN CUMULUS WITH BASES NEAR 4K FT WILL DEVELOP.
AFTER 18Z... EXPECT WIDELY SCATTERED THUNDERSTORMS... ESPECIALLY
VICINITY KAVL.
OUTLOOK...A RETURN TO MORE TYPICAL SUMMERTIME CONDITIONS IS EXPECTED
THROUGH THE WEEK...WITH MORNING CIG AND VSBY RESTRICTIONS IN FOG
MOST LIKELY IN THE MOUNTAINS.
CONFIDENCE TABLE...
00-06Z 06-12Z 12-18Z 18-24Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 99% HIGH 93% HIGH 98% HIGH 100%
KAVL HIGH 82% HIGH 81% HIGH 89% MED 60%
KHKY HIGH 100% HIGH 96% HIGH 97% HIGH 100%
KGMU HIGH 99% HIGH 97% HIGH 98% HIGH 100%
KAND HIGH 100% HIGH 91% HIGH 90% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...ARK
NEAR TERM...LGL
SHORT TERM...TS
LONG TERM...ARK
AVIATION...LGL
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1049 PM CDT SUN JUN 29 2014
.UPDATE...
ISSUED AT 1019 PM CDT SUN JUN 29 2014
ONE STRAY STORM IN EXTREME SOUTHEAST CORNER OF THE CWA WITHIN THE
LAST HOUR IS EXPECTED TO BE THE END OF EVENING ACTIVITY ACROSS THE
AREA...AND TRYING TO TIME POTENTIAL REDEVELOPMENT LATER TONIGHT IS
THE CHALLENGE OF THE NIGHT. EARLIER HI-RES WRF MODELS DEPICTED LITTLE
IF ANY REDEVELOPMENT PRIOR TO 12Z AS FAR NORTH AS OUR CWA...INSTEAD
CONFINING IT TO AREAS NEAR THE I-80 CORRIDOR WHERE BOTH THE ARW AND
NMM HELD THE 850MB FRONTAL BOUNDARY THROUGH THE LATE NIGHT HOURS...
WITH ACTIVITY THEN EXPANDING QUICKLY NORTHWARD INTO OUR SOUTHERN CWA
AFTER 12Z AS THE UPPER WAVE MOVES ACROSS THE REGION. 29/18Z NAM
SEEMED TO SHARE THIS IDEA...BUT 30/00Z RUNS NOW LIFT THE ELEVATED
WARM FRONT NORTH MORE QUICKLY...BRINGING STORM THREAT INTO OUR FAR
SOUTHERN AREAS DURING THE PRE-DAWN HOURS AS CURRENTLY DEPICTED IN OUR
FORECAST. RAP IS OF LITTLE HELP IN THE DECISION PROCESS...AS IT HAS
GROSSLY OVERDONE PRECIP ACROSS THE WESTERN PLAINS THROUGHOUT THE
EVENING...AND THUS LARGELY IGNORED IT FOR THE EVENING UPDATES.
GIVEN FAIR PERFORMANCE OF THE HIGH-RES MODELS OF LATE...AND SEEING A
FINE LINE/LOW LEVEL BOUNDARY DRIFTING SOUTH ON KLNX RADAR IN CENTRAL
NEBRASKA...IS TEMPTING TO CUT POPS FOR LATE TONIGHT IN OUR SOUTH.
TOUGH TO PULL COMPLETELY THOUGH...SO HAVE TRIMMED BACK TO JUST CHANCE
RANGE SOUTH OF I-90 THROUGH DAYBREAK WITH QUICK RAMP- UP JUST AFTER
12Z ACROSS NORTHWEST IOWA.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 316 PM CDT SUN JUN 29 2014
CONVECTION SO FAR HAS NOT REALLY BLOSSOMED TO SAY THE LEAST IN OUR
SOUTHEAST ZONES. 18Z SOUNDINGS FROM KOAX AND KTOP SHOW SOME FAIRLY
DECENT CAPPING FROM 900-850MB THAT NEEDS TO BE OVERCOME...AND ONE
CAN ASSUME THAT THE CAPPING IS PROBABLY EVEN WORSE IN NORTHWEST IA.
BUT THERE IS A WEAK BOUNDARY...WITH WEST TO SOUTHWEST WINDS NOTED
OVER MOST OF OUR FORECAST AREA...BUT A WEAK SOUTHERLY FLOW AT STORM
LAKE. IN ADDITION...A STOUT DRY LINE HAS MOVED EASTWARD GENERALLY
EXTENDING FROM JUST WEST OF YANKTON TO NEAR MARSHALL WHERE IT WILL
LIKELY STALL. THEREFORE CONVECTIVE CHANCES WILL BE LIMITED LIKELY
SOUTH OF A DIXON COUNTY NEBRASKA TO SPENCER IA LINE...WITH THE BEST
CHANCE FOR SEVERE STORMS PROBABLY CONFINED FROM SIOUX CITY TO STORM
LAKE. AND EVEN THAT ACTIVITY WILL LIKELY RAPIDLY WANE IN THE EARLY
EVENING HOURS...CERTAINLY BEFORE MIDNIGHT. LATER TONIGHT...THE
FORECAST AREA BEGINS TO FEEL THE EFFECTS OF A STRONG SHORT WAVE
MOVING DOWN THE BACKSIDE OF A STRONG UPPER LOW IN SOUTH CENTRAL
CANADA. THIS WAVE IS DIFFICULT TO NOTE ON CURRENT WATER VAPOR
IMAGERY NEAR THE MT AND CANADIAN BORDER...BUT WILL STRENGTHEN AS IT
MOVES DOWN THE WESTERN PLAINS. EVENTUALLY...THIS WAVE WILL GIVE
STRONG CHANCES FOR RAINFALL LATE TONIGHT AND MONDAY MORNING ALONG
AND SOUTH OF A TYNDALL SD TO JACKSON MN LINE. CHANCES FOR MEASURABLE
RAINFALL WILL ALSO EXIST NORTH OF THERE DEEPER INTO SOUTHEAST SD...
BUT AMOUNTS WILL VERY LIKELY BE LIGHTER. LOCALIZED RAINFALL AMOUNTS
OF 1 TO 2 INCHES COULD OCCUR IN NORTHWEST IA BEFORE ALL IS SAID AND
DONE WITH THIS SHORT WAVE ON MONDAY...BUT AVERAGE AMOUNTS WILL BE
MORE CONFINED IN THE HALF INCH TO TWO THIRDS OF AN INCH RANGE. SO
THUS HAVE NOT ISSUED A FLASH FLOOD WATCH FOR OUR SOUTHEAST ZONES.
CONCERNING TEMPERATURES...LOWS TONIGHT COULD VARY QUITE A BIT WITH
VALUES RANGING FROM THE MID TO UPPER 50S AROUND HURON IN THE DRY
AIR...TO MID TO UPPER 60S NEAR SIOUX CITY AND STORM LAKE. HIGHS ON
MONDAY WILL BE PLEASANT FOR THIS TIME OF YEAR WITH A LOT OF LOWER
80S...AND DRY AIR PREVALENT IN OUR WEST AND NORTH WHICH WILL
EVENTUALLY MOVE INTO NORTHWEST IA TOWARD MONDAY EVENING.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 316 PM CDT SUN JUN 29 2014
A COOL UPPER TROUGH WILL SETTLE OVER THE AREA FOR TUESDAY AND
WEDNESDAY. SKIES SHOULD START MONDAY NIGHT MOSTLY CLEAR BUT
NORTHWEST WINDS WILL REMAIN STRONG AS THEY CONTINUE TO BRING COLD
AIR IN THROUGH THE NIGHT. GENERALLY EXPECT WINDS FROM 10 TO 20 MPH
ALL NIGHT. IN ADDITION...CLOUDS WILL SPREAD SOUTH THROUGH THE
NIGHT AHEAD OF VORTICITY LOBE AND SECONDARY COLD FRONT. THE STRONG
WINDS AND MIXING WILL KEEP LOWS IN THE UPPER 50S TO AROUND 60. ON
TUESDAY...ANY SUN IN THE MORNING WILL QUICKLY GIVE WAY TO THICK
CUMULUS. THE INSTABILITY IN THE BOUNDARY LAYER IS NOT A DEEP AS
WAS SHOWN YESTERDAY BUT STILL ENOUGH TO RESULT IN SHOWERS OR EVEN
AN ISOLATED THUNDERSTORM. WITH SUCH COLD AIR ALOFT AND LARGE SCALE
ASCENT WITH THE UPPER VORTICITY LOBE...COULD SEE SHOWERS NORTH OF
I90 SHORTLY AFTER SUNRISE...ALTHOUGH THE BEST CHANCE WILL BE
DURING THE AFTERNOON WHEN TEMPERATURES HAVE MAXED OUT IN THE UPPER
60S TO LOWER 70S. HAVE THE HIGHEST PROBABILITIES IN SW MN WHERE
TEMPERATURES ARE COOLEST ABOVE THE SURFACE. WOULD NOT BE SURPRISED
IF MANY LOCATIONS ACTUALLY REACH THEIR HIGH AROUND NOON AND THEN
FLUCTUATE THE REMAINDER OF THE DAY BASED UPON WHEN PRECIPITATION
OCCURS. GIVEN THE UNCERTAINTY OF WHEN ANY ONE LOCATION WILL SEE
RAIN...BASICALLY HAVE STEADY TEMPS ALL AFTERNOON NEAR FORECAST
HIGHS. IT WILL ALSO BE WINDY MUCH OF THE DAY WITH SUSTAINED WINDS
OF 20 TO 30 MPH.
THE SHOWERS SHOULD DISSIPATE AROUND SUNSET AND WINDS SHOULD DROP TO
AROUND 10 MPH. WITH FAIRLY COOL AIR IN PLACE AND SOME CLEARING...
ESPECIALLY WEST OF I-29...LOWS WILL GENERALLY BE IN THE LOWER TO
MID 50S. ON WEDNESDAY...ANOTHER WEAK VORT LOBE WILL MOVE ACROSS MN
DURING THE LATE MORNING AND EARLY AFTERNOON. IT REMAINS UNSTABLE
IN THE BOUNDARY ACROSS SW MN AND NW IA SO KEPT A SLIGHT CHANCE OF
SHOWERS MOST OF THE DAY FROM MARSHALL TO STORM LAKE. ALTHOUGH
THERE WILL BE MORE SUN IN MOST LOCATIONS...TEMPERATURES WILL NOT
BE MUCH WARMER WITH HIGHS FROM AROUND 70 OVER MUCH OF SW MN AND NW
IA TO THE MID 70S WEST OF THE JAMES RIVER.
FOR THU THROUGH SUNDAY...ALL MODELS SHOW THE LONG WAVE TROUGH MOVING
EAST WITH RISING 500 MB HEIGHTS THROUGH THE WEEK. THIS RESULTS IN
A SLOW WARMING TREND FOR LATE IN THE WEEK AS THE STRONGER
WESTERLIES SHIFT TOWARD THE CANADIAN BORDER. PRECIPITATION CHANCES
FOR THE HOLIDAY WEEKEND DEPEND UPON TIMING OF WEAK WAVES MOVING
OVER THE TOP OF THE RIDGE AND INTO THE EASTERN PLAINS. THESE TYPE
OF WAVES ARE NOTORIOUSLY DIFFICULT TO FORECAST BEYOND A COUPLE OF
DAYS MAKING ANY PRECIPITATION FORECAST RELATIVELY UNCERTAIN. SO
WHILE THE 06Z GFS WITH A TROUGH DEVELOPING IN MN/IA ON SUNDAY IS
POSSIBLE...IT REALLY DEPENDS UPON THE EVOLUTION OF A WAVE IN THE
NW FLOW FROM SATURDAY. THE 00Z AND 12Z ECMWF AS WELL AS THE 12Z
GEM AND 12Z GFS ALSO HAVE THIS WAVE MOVE THROUGH THE EASTERN
PLAINS ON SATURDAY BUT DO NOT DEEPEN IT. THE ECMWF IS WEAKEST WITH
THIS WAVES AND CONTINUES TO BUILD THE RIDGE OVER THE AREA. AT THIS
POINT...WILL LEAN TOWARD THIS SOLUTION WHICH WOULD MEAN A BIT
WARMER TEMPERATURES FOR SUNDAY. OVERALL WILL HAVE CHANCE OF
THUNDERSTORMS FROM LATE THURSDAY NIGHT INTO SATURDAY NIGHT. THE
BEST CHANCE FOR STORMS WILL BE FRIDAY AFTERNOON AND FRIDAY NIGHT. AS
FOR TEMPERATURES...WILL START OUT BELOW NORMAL ON THURSDAY AND
WARMING TO NORMAL BY THE WEEKEND. FORECAST HIGHS ARE LEAST
CERTAIN ON SATURDAY SINCE IF THERE IS CONVECTION LATE FRIDAY
NIGHT...LINGERING CLOUDS COULD KEEP TEMPERATURES COOLER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1049 PM CDT SUN JUN 29 2014
MOSTLY VFR THROUGH 01/06Z. THE MAIN EXCEPTION WILL BE SCATTERED
TO NUMEROUS SHRA/TSRA EXPECTED SOUTHEAST OF A YKN/MJQ LINE...OR TO
THE S AND E OF FSD ...10Z-18Z WITH LOCAL AND BRIEF LOWERING TO
MVFR CEILINGS AND VISIBILITIES. AFTER 01/03Z CEILINGS 3-5K FEET
MAY BEGIN TO INCREASE OVER THE NORTHERN PART OF THE AREA. A FEW
SURFACE GUSTS TO 25 KNOTS FROM THE WEST WILL BE POSSIBLE IN
SOUTHEAST SD 16Z-01/00Z.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
UPDATE...JH
SHORT TERM...MJ
LONG TERM...SCHUMACHER
AVIATION...
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1019 PM CDT SUN JUN 29 2014
.UPDATE...
ISSUED AT 1019 PM CDT SUN JUN 29 2014
ONE STRAY STORM IN EXTREME SOUTHEAST CORNER OF THE CWA WITHIN THE
LAST HOUR IS EXPECTED TO BE THE END OF EVENING ACTIVITY ACROSS THE
AREA...AND TRYING TO TIME POTENTIAL REDEVELOPMENT LATER TONIGHT IS
THE CHALLENGE OF THE NIGHT. EARLIER HI-RES WRF MODELS DEPICTED LITTLE
IF ANY REDEVELOPMENT PRIOR TO 12Z AS FAR NORTH AS OUR CWA...INSTEAD
CONFINING IT TO AREAS NEAR THE I-80 CORRIDOR WHERE BOTH THE ARW AND
NMM HELD THE 850MB FRONTAL BOUNDARY THROUGH THE LATE NIGHT HOURS...
WITH ACTIVITY THEN EXPANDING QUICKLY NORTHWARD INTO OUR SOUTHERN CWA
AFTER 12Z AS THE UPPER WAVE MOVES ACROSS THE REGION. 29/18Z NAM
SEEMED TO SHARE THIS IDEA...BUT 30/00Z RUNS NOW LIFT THE ELEVATED
WARM FRONT NORTH MORE QUICKLY...BRINGING STORM THREAT INTO OUR FAR
SOUTHERN AREAS DURING THE PRE-DAWN HOURS AS CURRENTLY DEPICTED IN OUR
FORECAST. RAP IS OF LITTLE HELP IN THE DECISION PROCESS...AS IT HAS
GROSSLY OVERDONE PRECIP ACROSS THE WESTERN PLAINS THROUGHOUT THE
EVENING...AND THUS LARGELY IGNORED IT FOR THE EVENING UPDATES.
GIVEN FAIR PERFORMANCE OF THE HIGH-RES MODELS OF LATE...AND SEEING A
FINE LINE/LOW LEVEL BOUNDARY DRIFTING SOUTH ON KLNX RADAR IN CENTRAL
NEBRASKA...IS TEMPTING TO CUT POPS FOR LATE TONIGHT IN OUR SOUTH.
TOUGH TO PULL COMPLETELY THOUGH...SO HAVE TRIMMED BACK TO JUST CHANCE
RANGE SOUTH OF I-90 THROUGH DAYBREAK WITH QUICK RAMP- UP JUST AFTER
12Z ACROSS NORTHWEST IOWA.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 316 PM CDT SUN JUN 29 2014
CONVECTION SO FAR HAS NOT REALLY BLOSSOMED TO SAY THE LEAST IN OUR
SOUTHEAST ZONES. 18Z SOUNDINGS FROM KOAX AND KTOP SHOW SOME FAIRLY
DECENT CAPPING FROM 900-850MB THAT NEEDS TO BE OVERCOME...AND ONE
CAN ASSUME THAT THE CAPPING IS PROBABLY EVEN WORSE IN NORTHWEST IA.
BUT THERE IS A WEAK BOUNDARY...WITH WEST TO SOUTHWEST WINDS NOTED
OVER MOST OF OUR FORECAST AREA...BUT A WEAK SOUTHERLY FLOW AT STORM
LAKE. IN ADDITION...A STOUT DRY LINE HAS MOVED EASTWARD GENERALLY
EXTENDING FROM JUST WEST OF YANKTON TO NEAR MARSHALL WHERE IT WILL
LIKELY STALL. THEREFORE CONVECTIVE CHANCES WILL BE LIMITED LIKELY
SOUTH OF A DIXON COUNTY NEBRASKA TO SPENCER IA LINE...WITH THE BEST
CHANCE FOR SEVERE STORMS PROBABLY CONFINED FROM SIOUX CITY TO STORM
LAKE. AND EVEN THAT ACTIVITY WILL LIKELY RAPIDLY WANE IN THE EARLY
EVENING HOURS...CERTAINLY BEFORE MIDNIGHT. LATER TONIGHT...THE
FORECAST AREA BEGINS TO FEEL THE EFFECTS OF A STRONG SHORT WAVE
MOVING DOWN THE BACKSIDE OF A STRONG UPPER LOW IN SOUTH CENTRAL
CANADA. THIS WAVE IS DIFFICULT TO NOTE ON CURRENT WATER VAPOR
IMAGERY NEAR THE MT AND CANADIAN BORDER...BUT WILL STRENGTHEN AS IT
MOVES DOWN THE WESTERN PLAINS. EVENTUALLY...THIS WAVE WILL GIVE
STRONG CHANCES FOR RAINFALL LATE TONIGHT AND MONDAY MORNING ALONG
AND SOUTH OF A TYNDALL SD TO JACKSON MN LINE. CHANCES FOR MEASURABLE
RAINFALL WILL ALSO EXIST NORTH OF THERE DEEPER INTO SOUTHEAST SD...
BUT AMOUNTS WILL VERY LIKELY BE LIGHTER. LOCALIZED RAINFALL AMOUNTS
OF 1 TO 2 INCHES COULD OCCUR IN NORTHWEST IA BEFORE ALL IS SAID AND
DONE WITH THIS SHORT WAVE ON MONDAY...BUT AVERAGE AMOUNTS WILL BE
MORE CONFINED IN THE HALF INCH TO TWO THIRDS OF AN INCH RANGE. SO
THUS HAVE NOT ISSUED A FLASH FLOOD WATCH FOR OUR SOUTHEAST ZONES.
CONCERNING TEMPERATURES...LOWS TONIGHT COULD VARY QUITE A BIT WITH
VALUES RANGING FROM THE MID TO UPPER 50S AROUND HURON IN THE DRY
AIR...TO MID TO UPPER 60S NEAR SIOUX CITY AND STORM LAKE. HIGHS ON
MONDAY WILL BE PLEASANT FOR THIS TIME OF YEAR WITH A LOT OF LOWER
80S...AND DRY AIR PREVALENT IN OUR WEST AND NORTH WHICH WILL
EVENTUALLY MOVE INTO NORTHWEST IA TOWARD MONDAY EVENING.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 316 PM CDT SUN JUN 29 2014
A COOL UPPER TROUGH WILL SETTLE OVER THE AREA FOR TUESDAY AND
WEDNESDAY. SKIES SHOULD START MONDAY NIGHT MOSTLY CLEAR BUT
NORTHWEST WINDS WILL REMAIN STRONG AS THEY CONTINUE TO BRING COLD
AIR IN THROUGH THE NIGHT. GENERALLY EXPECT WINDS FROM 10 TO 20 MPH
ALL NIGHT. IN ADDITION...CLOUDS WILL SPREAD SOUTH THROUGH THE
NIGHT AHEAD OF VORTICITY LOBE AND SECONDARY COLD FRONT. THE STRONG
WINDS AND MIXING WILL KEEP LOWS IN THE UPPER 50S TO AROUND 60. ON
TUESDAY...ANY SUN IN THE MORNING WILL QUICKLY GIVE WAY TO THICK
CUMULUS. THE INSTABILITY IN THE BOUNDARY LAYER IS NOT A DEEP AS
WAS SHOWN YESTERDAY BUT STILL ENOUGH TO RESULT IN SHOWERS OR EVEN
AN ISOLATED THUNDERSTORM. WITH SUCH COLD AIR ALOFT AND LARGE SCALE
ASCENT WITH THE UPPER VORTICITY LOBE...COULD SEE SHOWERS NORTH OF
I90 SHORTLY AFTER SUNRISE...ALTHOUGH THE BEST CHANCE WILL BE
DURING THE AFTERNOON WHEN TEMPERATURES HAVE MAXED OUT IN THE UPPER
60S TO LOWER 70S. HAVE THE HIGHEST PROBABILITIES IN SW MN WHERE
TEMPERATURES ARE COOLEST ABOVE THE SURFACE. WOULD NOT BE SURPRISED
IF MANY LOCATIONS ACTUALLY REACH THEIR HIGH AROUND NOON AND THEN
FLUCTUATE THE REMAINDER OF THE DAY BASED UPON WHEN PRECIPITATION
OCCURS. GIVEN THE UNCERTAINTY OF WHEN ANY ONE LOCATION WILL SEE
RAIN...BASICALLY HAVE STEADY TEMPS ALL AFTERNOON NEAR FORECAST
HIGHS. IT WILL ALSO BE WINDY MUCH OF THE DAY WITH SUSTAINED WINDS
OF 20 TO 30 MPH.
THE SHOWERS SHOULD DISSIPATE AROUND SUNSET AND WINDS SHOULD DROP TO
AROUND 10 MPH. WITH FAIRLY COOL AIR IN PLACE AND SOME CLEARING...
ESPECIALLY WEST OF I-29...LOWS WILL GENERALLY BE IN THE LOWER TO
MID 50S. ON WEDNESDAY...ANOTHER WEAK VORT LOBE WILL MOVE ACROSS MN
DURING THE LATE MORNING AND EARLY AFTERNOON. IT REMAINS UNSTABLE
IN THE BOUNDARY ACROSS SW MN AND NW IA SO KEPT A SLIGHT CHANCE OF
SHOWERS MOST OF THE DAY FROM MARSHALL TO STORM LAKE. ALTHOUGH
THERE WILL BE MORE SUN IN MOST LOCATIONS...TEMPERATURES WILL NOT
BE MUCH WARMER WITH HIGHS FROM AROUND 70 OVER MUCH OF SW MN AND NW
IA TO THE MID 70S WEST OF THE JAMES RIVER.
FOR THU THROUGH SUNDAY...ALL MODELS SHOW THE LONG WAVE TROUGH MOVING
EAST WITH RISING 500 MB HEIGHTS THROUGH THE WEEK. THIS RESULTS IN
A SLOW WARMING TREND FOR LATE IN THE WEEK AS THE STRONGER
WESTERLIES SHIFT TOWARD THE CANADIAN BORDER. PRECIPITATION CHANCES
FOR THE HOLIDAY WEEKEND DEPEND UPON TIMING OF WEAK WAVES MOVING
OVER THE TOP OF THE RIDGE AND INTO THE EASTERN PLAINS. THESE TYPE
OF WAVES ARE NOTORIOUSLY DIFFICULT TO FORECAST BEYOND A COUPLE OF
DAYS MAKING ANY PRECIPITATION FORECAST RELATIVELY UNCERTAIN. SO
WHILE THE 06Z GFS WITH A TROUGH DEVELOPING IN MN/IA ON SUNDAY IS
POSSIBLE...IT REALLY DEPENDS UPON THE EVOLUTION OF A WAVE IN THE
NW FLOW FROM SATURDAY. THE 00Z AND 12Z ECMWF AS WELL AS THE 12Z
GEM AND 12Z GFS ALSO HAVE THIS WAVE MOVE THROUGH THE EASTERN
PLAINS ON SATURDAY BUT DO NOT DEEPEN IT. THE ECMWF IS WEAKEST WITH
THIS WAVES AND CONTINUES TO BUILD THE RIDGE OVER THE AREA. AT THIS
POINT...WILL LEAN TOWARD THIS SOLUTION WHICH WOULD MEAN A BIT
WARMER TEMPERATURES FOR SUNDAY. OVERALL WILL HAVE CHANCE OF
THUNDERSTORMS FROM LATE THURSDAY NIGHT INTO SATURDAY NIGHT. THE
BEST CHANCE FOR STORMS WILL BE FRIDAY AFTERNOON AND FRIDAY NIGHT. AS
FOR TEMPERATURES...WILL START OUT BELOW NORMAL ON THURSDAY AND
WARMING TO NORMAL BY THE WEEKEND. FORECAST HIGHS ARE LEAST
CERTAIN ON SATURDAY SINCE IF THERE IS CONVECTION LATE FRIDAY
NIGHT...LINGERING CLOUDS COULD KEEP TEMPERATURES COOLER.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 630 PM CDT SUN JUN 29 2014
GENERALLY VFR THROUGH 31/00Z. ONE EXCEPTION WILL BE ISOLATED TSRA
WITH VERY LOCAL AND BRIEF LOWERING TO MVFR THROUGH 03Z ONLY IN THE
AREA EAST OF KSUX TO SLB. THE MAIN EXCEPTION TO VFR WILL BE SCATTERED
TO NUMEROUS SHRA/TSRA EXPECTED SOUTHEAST OF A YKN/MJQ LINE...OR
TO THE S AND E OF FSD ...10Z-18Z WITH LOCAL AND BRIEF LOWERING TO
MVFR CEILINGS AND VISIBILITIES.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
UPDATE...JH
SHORT TERM...MJ
LONG TERM...SCHUMACHER
AVIATION...
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
1131 PM MDT FRI JUN 27 2014
.UPDATE...
ISSUED AT 852 PM MDT FRI JUN 27 2014
COMPLEX OF THUNDERSTORMS CONTINUES TO MOVE NORTHEAST ACROSS EASTERN
PORTIONS OF THE CWA AS UPPER TROF PIVOTS THROUGH THE AREA. ANOTHER
BOWED LINE OF STORMS IS MOVING QUICKLY ACROSS NORTH CENTRAL NEB
AND WILL MOVE INTO SOUTH CENTRAL SD WITHIN THE NEXT HOUR. THE
THREAT FOR SEVERE STORMS WILL GRADUALLY DIMINISH OVER FAR
NORTHERN AND EASTERN PORTIONS OF THE CWA OVER THE NEXT HOUR OR
TWO...WITH THE GREATEST RISK TOWARD CENTRAL SD.
SLOW MOVING THUNDERSTORMS HAVE PRODUCED A LOT OF RAIN ACROSS
PORTIONS OF NORTHWESTERN SD...ESPECIALLY OVER PERKINS CO. FLASH
FLOOD WARNINGS ARE IN EFFECT FOR NORTHEASTERN AND SOUTHERN
PORTIONS OF PERKINS COUNTY...WHERE 2 TO 4 INCHES OF RAIN HAS BEEN
ESTIMATED BY RADAR. ANOTHER INCH OR MORE OF RAINFALL IS POSSIBLE
ACROSS THE AREA THROUGH THE REST OF THE EVENING.
HAVE UPDATED TO REMOVE THE FLASH FLOOD WATCH FROM NORTHEAST WY AND
SOUTHWESTERN SD...WHILE ALSO CANCELLING THE SEVERE THUNDERSTORM
WATCH FOR MUCH OF FAR WESTERN SD. THERE IS ANOTHER UPPER LEVEL
WAVE ROTATING THROUGH THE TROF...WITH SCATTERED SHOWERS AND
THUNDERSTORMS ACROSS NORTH CENTRAL INTO EASTERN WY. WILL KEEP
CHANCES FOR PCPN LINGERING THROUGH THE NIGHT FOR MOST AREAS.
&&
.SHORT TERM...THIS EVENING THROUGH SATURDAY NIGHT
ISSUED AT 149 PM MDT FRI JUN 27 2014
WATER VAPOR IMAGERY SHOWS AN UPPER TROUGH ACROSS THE NRN TO CNTRL
ROCKIES AREA WITH SEVERAL WAVES ALONG THE MAIN AXIS OVER WY TO THE
CNTRL HIGH PLAINS. SURFACE ANALYSIS SHOWS LOW PRESSURE ACROSS THE
WRN DAKOTAS. OBS SHOW A SLOW MOVING COLD FRONT STATIONED NEAR THE
SD/WY BORDER...WITH 10+ DEGREE TEMP DIFFERENCE FROM NE WY TO WRN SD.
LARGE SCALE ASCENT WILL CONTINUE TO INCREASE THIS AFTERNOON AS UPPER
FORCING SLIDES NORTHWARD WITH THE NEXT WAVE. KUDX RADAR SHOWING
SHOWERS/STORMS BEGINNING TO INCREASE IN COVERAGE AT THIS TIME.
STRONGEST CAPE WILL BE STRONGEST ACROSS CNTRL SD AT 1500
J/KG...OTHERWISE WEAK CAPE ACROSS NE WY WILL HINDER ANY SIGNIFICANTLY
STRONG UPDRAFTS AND LIMIT HAIL POTENTIAL. NAM KEEPS DCAPE WEAK OVER
MUCH OF THE CWA...BUT LATEST RAP DOES BRING SOME HIGHER DCAPE TO WRN
SD SUGGESTING A POTENTIAL FOR STRONG WINDS ALONG WITH HAIL. HEAVY
RAIN/FLOODING THREAT CONTINUES THROUGH THE EVNG WITH AMPLE MOISTURE
AND AN ALREADY SATURATED GROUND FROM RECENT HEAVY RAINS. WILL KEEP
THE FLASH FLOOD WATCH GOING.
CYCLONIC FLOW WILL CONTINUE SATURDAY WITH A SERIES OF WAVES CROSSING
THE REGION. DRIER POST FRONTAL AIRMASS WILL KEEP INSTABILITY WEAK
ACROSS THE CWA...BUT ENOUGH FOR SOME SHOWERS/STORMS TO POP UP
ESPECIALLY TOWARD THE AFTERNOON. SO WILL CONTINUE LOW CHANCE POPS
THROUGH THE DAY. SHOWERS WILL MOSTLY DISSIPATE BY EVENING. TEMPS
WILL BE NEAR AVERAGE SATURDAY.
&&
.LONG TERM...SUNDAY THROUGH FRIDAY
ISSUED AT 149 PM MDT FRI JUN 27 2014
DRIER WX WILL BEGIN WORKING INTO THE REGION ON SUNDAY AS THE UPPER
LEVEL TROF PUSHES TO OUR EAST. AN UPPER LEVEL RIDGE WILL THEN BUILD
IN BEHIND IT FROM WESTERN NORTH AMERICA...MOVING INTO THE PLAINS
STATES THROUGH NEXT WEEK. MAINLY DRY WEATHER IS EXPECTED WITH SLOWLY
WARMING TEMPERATURES...WITH ABOVE AVERAGE READINGS POSSIBLE BY THE
END OF THE WEEK. THERE COULD BE A FEW DISTURBANCES THAT MOVE THROUGH
THE RIDGE AND BRING A THUNDERSTORM OR TWO LATER IN THE WEEK...BUT
MOST AREAS SHOULD REMAIN DRY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1122 PM MDT FRI JUN 27 2014
MID LEVEL IMPULSE AND ASSOCIATED CONVECTION WILL SHIFT EAST OUT OF
THE AREA OVERNIGHT. LINGERING POCKET OF MVFR CIGS OVER THE
NORTHERN/CENTRAL BLACK HILLS AND NE WY ARE EXPECTED TO DIMINISH AS
DRIER AIR CONTINUES TO WORK INTO THE REGION. A BRIEF PERIOD OF
MVFR BR IS POSSIBLE INVOF OF KGCC TONIGHT...BEFORE LL FLOW BEGINS
TO INCREASE WITH DRY AIR MIXING DOWN. OTHERWISE...VFR CONDS
EXPECTED OVER THE REMAINDER OF THE FA. ANOTHER WEAK IMPULSE WILL
ADVECT THROUGH THE AREA SAT...BRINGING SCT SHRA/TS TO THE FA...ESP
NORTHERN PORTIONS OF THE FA IN THE AFTERNOON.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
UPDATE...26
SHORT TERM...13
LONG TERM...JOHNSON
AVIATION...JC
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
743 PM CDT SUN JUN 29 2014
.UPDATE...FOR 00Z TAFS...
&&
.AVIATION...
A CHANCE OF SHOWERS AND THUNDERSTORMS WILL CONTINUE THIS EVENING.
MOSTLY JUST ISOLATED ACTIVITY, SO DIDN`T INCLUDE PRECIP AT CKV AND
BNA. STILL SOME SHOWERS MOVING ACROSS THE NORTHERN CUMBERLAND
PLATEAU, SO LEFT A VCSH AT CSV UNTIL 03Z. CONDITIONS APPEAR
FAVORABLE FOR FOG AFTER 06Z WITH 3SM TO 5SM LIKELY AT ALL SITES.
CIGS ARE FORECAST TO FALL OVERNIGHT INTO THE IFR AND MVFR RANGE.
ANOTHER ROUND OF SHOWERS IS LIKELY AFTER 14Z MONDAY WITH
SCATTERED SHOWERS AND THUNDERSTORMS POSSIBLE THROUGH EARLY
AFTERNOON. CIGS SHOULD BEGIN TO IMPROVE AROUND 20Z AS A SHORTWAVE
PUSHES EAST OF MIDDLE TENNESSEE.
&&
.PREV DISCUSSION... /ISSUED 547 PM CDT SUN JUN 29 2014/
MESOSCALE UPDATE...DISCUSSION VALID THROUGH 06Z
CONVECTION CURRENTLY JUST OFF TO THE EAST OF NASHVILLE PRODUCED
WIND GUSTS 30 TO 40 MPH AROUND THE LEBANON AREA LAST HALF HOUR
WITH LOCALLY HEAVY RAINFALL. ONE LEBANON OBSERVER MEASURED 1.22
INCHES OF RAIN WITHIN A 30 MINUTE PERIOD ENDING AT 530 PM CAUSING
PONDING OF WATER IN LOW LYING AREAS. AS BE SEEN IN MOSAIC MOST IF
NOT ALL OF THE CONVECTION IS NOW IN EASTERN MIDDLE TENNESSEE AND
ALONG PLATEAU. AREAS WEST OF INTERSTATE 65 ARE CURRENTLY FREE OF
CONVECTION. LOOKING AT LATEST RUC RUN MID LEVEL SHORT WAVE AXIS IS
DOWN THROUGH CENTRAL TENNESSEE AS DEPICTED BY 700 MBARS BY WIND AND
HEIGHT FIELDS. SHORT WAVE AXIS WILL GRADUALLY SLIP EASTWARD THIS
EVENING KEEPING CONVECTION CHANCES MAINLY EASTERN MIDDLE AND
PLATEAU AT LEAST THROUGH 06Z. AREAS WEST OF INTERSTATE 65 LIKELY
TO REMAIN DRY.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
11
AREA FORECAST DISCUSSION...UPDATED
NWS MORRISTOWN TN
951 AM EDT SAT JUN 28 2014
.DISCUSSION...
A MIDLEVEL SHORTWAVE TROUGH IS MOVING ACROSS THE AREA THIS MORNING.
ADDITIONAL SHOWERS ARE EXPECTED TO DEVELOP THIS AFTERNOON AS THE
TROUGH MOVES NE...WHICH WILL FAVOR NORTHERN SECTIONS FOR PRECIP
COVERAGE. THE RAP AND THE HRRR AGREE WITH THIS PATTERN...AND WILL
RAISE POPS NORTH SLIGHTLY BUT REMAIN IN THE LIKELY RANGE. POPS WILL
BE LOWERED SLIGHTLY SOUTH TO HIGH CHANCES. LOCALLY HEAVY RAIN WILL
BE THE MAIN ISSUE WITH THE SHOWERS. TEMPERATURES MAY NEED TO BE
NUDGED DOWN A BIT BASED ON LATEST LAMP GUIDANCE.
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DGS
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
1042 PM CDT SUN JUN 29 2014
.DISCUSSION...ONLY CHANGE FROM PREVIOUS UPDATE WAS TO INCREASE
CLOUD COVER OVER THE COASTAL PLAINS AS STRATUS CONTINUES TO
DEVELOP WITH LOW LEVEL JET INCREASING TO 30-35 KNOTS.
&&
.MARINE...WIND SPEEDS HAVE SUBSIDED OVER THE SOUTHERN BAYS AND
HAVE CANCELLED THE SCA EARLY. THE WINDS REMAIN STRONG AT BOB HALL
PIER AND PORT ARANSAS CMAN. SREF AND HRRR MODELS ARE IN AGREEMENT
THAT WINDS WILL DIMINISH AROUND 06Z AND KEPT SCA EXPIRATION AS IS.
&&
.PREV DISCUSSION... /ISSUED 602 PM CDT SUN JUN 29 2014/
DISCUSSION...SEE AVIATION DISCUSSION BELOW FOR THE 00Z TAFS.
AVIATION...A FAIRLY PERSISTENT FCST IS EXPECTED FOR S TX WITH VFR
CONDITIONS PREVAILING THROUGH THE EVENING THEN MVFR CIGS DVLPG
OVERNIGHT IN RESPONSE TO A 30-35KT LLJ. VFR CONDITIONS RESUME BY
MID MORNING ON MONDAY. SFC WINDS WILL DECREASE THIS EVENING BUT
REMAIN ELEVATED OVERNIGHT...THUS LLWS IS NOT ANTICIPATED. SFC
WINDS RESTRENGTHEN THROUGH MID MORNING WITH GUSTS RANGING FROM
22-30KTS DURING THE DAY MONDAY.
PREV DISCUSSION... /ISSUED 552 PM CDT SUN JUN 29 2014/
DISCUSSION...SEE MARINE SECTION FOR SMALL CRAFT ADVISORY ISSUANCE.
MARINE...STRONG THERMAL GRADIENT OVER THE SOUTHERN COASTAL BEND
HAS INCREASED WIND SPEEDS TO SCA CRITERIA. SOUTH-SOUTHEAST LOW LEVEL
FLOW WILL INCREASE TO 25-35 KNOTS ALONG THE COAST THIS EVENING...SO
WILL KEEP SCA UP UNTIL 04Z FOR SOUTHERN BAYS AND 06Z FOR SOUTHERN
NEAR SHORE WATERS. WILL WATCH TRENDS THIS EVENING...MAY NEED TO
EXTEND SCA LATER TONIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 78 94 77 97 78 / 10 10 10 10 10
VICTORIA 78 94 76 94 77 / 10 10 10 10 10
LAREDO 78 103 77 104 79 / 10 10 10 10 10
ALICE 77 97 76 100 77 / 10 10 10 10 10
ROCKPORT 80 89 81 92 80 / 10 10 10 10 10
COTULLA 77 100 76 102 76 / 10 10 10 10 10
KINGSVILLE 78 97 77 99 77 / 10 10 10 10 10
NAVY CORPUS 80 89 80 92 80 / 10 10 10 10 10
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 1 AM CDT MONDAY FOR THE FOLLOWING
ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT ARANSAS OUT
20 NM.
&&
$$
TT/89...SHORT TERM
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1129 PM CDT FRI JUN 27 2014
.AVIATION...
MVFR CIGS ARE BEGINNING TO OVERSPREAD THE I-35 TAF SITES AND WILL
BEGIN THE 06Z TAFS WITH MVFR CONDITIONS. WIND SPEEDS WILL REMAIN
OVER 10 KNOTS OVERNIGHT AS A LLJ SETS UP ACROSS THE AREA. THIS
SHOULD PREVENT IFR CIGS FOR MOST OF THE NIGHT...BUT IT IS POSSIBLE
MAINLY AROUND DAYBREAK. BREEZY CONDITIONS ARE EXPECTED IN THE
AFTERNOON WITH GUSTS BETWEEN 25 AND 30 KNOTS. ANOTHER ROUND OF
MVFR STRATUS IS EXPECTED TOMORROW NIGHT. RAIN CHANCES ARE TOO LOW
TO MENTION WITH THE HIGHEST PROBABILITIES EAST OF THE TAF SITES.
HAMPSHIRE
&&
.PREV DISCUSSION... /ISSUED 848 PM CDT FRI JUN 27 2014/
UPDATE...
COASTAL PLAINS SHOWERS AND THUNDERSTORMS ARE TAPERING OFF EARLY
THIS EVENING. SOME OF THESE SHOWERS COULD AFFECT THE SOUTHERN
PORTION OF LAVACA COUNTY WITHIN THE HOUR...OTHERWISE...DRY
WEATHER CONDITIONS ARE EXPECTED FOR MUCH OF THE AREA THE REST OF
TONIGHT. LATER TONIGHT...FEW SHOWERS OR AN ISOLATED THUNDERSTORM
COULD AFFECT THE NORTHWEST PART OF VAL VERDE COUNTY. THESE STORMS
ARE PUSHING EASTWARD AHEAD OF A DRY-LINE OVER WEST TEXAS. IF THE
STORMS DO MAKE IT INTO NORTHWEST VAL VERDE COUNTY...COULD PRODUCE
FEW HUNDREDTHS OF AN INCH OF RAINFALL. A DRYING TREND IS IN STORE
FOR THE UPCOMING WEEKEND WITH SEA BREEZE CONVECTION TYPE SATURDAY
AFTERNOON MAINLY ALONG AND EAST OF HIGHWAY 183.
PREV DISCUSSION... /ISSUED 307 PM CDT FRI JUN 27 2014/
SHORT TERM (TODAY THROUGH SATURDAY)...WEAK MID AND UPPER LEVEL
SHEAR AXIS REMAINS ACROSS THE EASTERN CWA TODAY. ISOLATED SHOWERS
ALONG AND EAST OF I-35 WILL GRADUALLY END AROUND SUNSET. HRRR AND
GFS INDICATING THE POTENTIAL FOR ISOLATED SHOWERS AND THUNDERSTORMS
MAKING IT INTO VAL VERDE COUNTY TONIGHT...ASSOCIATED WITH TAIL
END OF FORCING FROM MID AND UPPER LEVEL SHORTWAVE COMING OUT OF NM
INTO WEST TEXAS THIS AFTERNOON AND EVENING. HAVE A LOW 10-20 POP
OUT ACROSS VAL VERDE TO ACCOUNT FOR THIS TONIGHT. THE LOW AND MID
LEVEL MOISTURE AXIS HANGS ON ALONG AND EAST OF I-35 INTO SATURDAY.
ONE MORE DAY OF ISOLATED TO LOW END SCATTERED SHOWERS AND
THUNDERSTORMS ACROSS THE REGION ON SATURDAY...BEFORE DRYING TAKES
PLACE.
LONG TERM (SATURDAY NIGHT THROUGH THURSDAY)...MID LEVEL DRYING IS
INDICATED BY MODELS SUNDAY AND MONDAY ACROSS SOUTH-CENTRAL TEXAS...
WITH FLAT UPPER LEVEL RIDGE BUILDING JUST TO NORTH. WARMING TREND
WITH DRY CONDITIONS ARE FORECAST SUNDAY THROUGH MONDAY. A MODEST
INCREASE IN MOISTURE TAKES PLACE ACROSS SOUTHERN AND EASTERN ZONES
TUESDAY THROUGH FRIDAY...BENEATH THE RIDGE TO THE NORTH. ISOLATED
CONVECTION ACROSS SOUTHEASTERN COUNTIES WILL BE POSSIBLE MAINLY
IN THE AFTERNOONS WEDNESDAY THROUGH FRIDAY WITH JUST A SLIGHT
REDUCTION IN TEMPS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 76 92 78 93 76 / 10 20 10 - -
AUSTIN BERGSTROM INTL AIRPORT 76 93 77 93 76 / 10 20 10 - -
NEW BRAUNFELS MUNI AIRPORT 75 92 77 94 77 / 10 20 10 - -
BURNET MUNI AIRPORT 73 90 75 90 73 / 10 20 10 - -
DEL RIO INTL AIRPORT 77 96 78 95 77 / 10 - - - -
GEORGETOWN MUNI AIRPORT 75 92 76 92 75 / 10 20 10 - -
HONDO MUNI AIRPORT 75 92 76 94 75 / 10 10 10 - -
SAN MARCOS MUNI AIRPORT 76 92 77 93 77 / 10 20 10 - -
LA GRANGE - FAYETTE REGIONAL 77 92 78 92 77 / 20 20 10 - -
SAN ANTONIO INTL AIRPORT 77 92 78 94 77 / 10 20 10 - -
STINSON MUNI AIRPORT 76 93 78 94 77 / 10 20 10 - -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...26
SYNOPTIC/GRIDS...17
AREA FORECAST DISCUSSION
NWS PORTLAND OR
253 AM PDT SAT JUN 28 2014
.SYNOPSIS...A FINAL FEW SHORTWAVES WILL MOVE THROUGH THE PACIFIC NW
THIS WEEKEND WITH A STRONG WESTERLY JET ALOFT. THE JET WILL SHIFT N
BY THE END OF THE WEEKEND THEN A SURFACE HIGH PRES SYSTEM WILL
BUILD OFF THE COAST SUN NIGHT...AND MOVE INLAND EARLY IN THE WEEK TO
BRING A RETURN TO DRY WARM WEATHER.
&&
.SHORT TERM...A FEW SHOWERS REMAINED ON RADAR EARLY SAT MORNING...
MAINLY OFF THE S WA AND FAR N OREGON PART OF THE COAST. A STRONG JET
REMAINED ACROSS THE N PACIFIC EXTENDING INLAND OVER FAR NORTHERN
OREGON. MODELS CONTINUE TO DEPICT SEVERAL SHORTWAVES TRACKING E INTO
WA OVER THE NEXT 36 HOURS AS THE JET AXIS SLOWLY LIFTS N INTO WA.
THE MOST OBVIOUS OF THE WAVES IS SEEN IN WATER VAPOR PICTURES THIS
MORNING N OF 45N CROSSING 135W. MODELS BRING THIS WAVE INLAND THIS
AFTERNOON...BUT ON A TRACK N OF THE REGION. MODEL SOUNDINGS STILL
SHOW AMPLE MOISTURE AND INSTABAILITY BELOW ABOUT 700 MB TODAY...BUT
IN TIME THE SUBSIDENCE INVERSION LOWERS...GRADUALLY REDUCING THE
THREAT FOR SHOWERS. OVERALL WILL CONTINUE WITH ONLY MINOR CHANGES TO
THE FORECAST...INDICATING THE BEST CHANCES FOR SHOWERS TODAY ESP IN
THE N...THEN DECREASING SAT NIGHT AND SUN.
BY SUN NIGHT AND MON AIR MASS STABILIZES WITH RIDGING ALOFT AND THE
LOW LEVEL FLOW BECOMES MORE NORTHERLY. THIS RESULTS IN A RETURN TO
DRIER WEATHER AS WELL AS SIGNIFICANTLY WARMER TEMPS FOR MON.
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS. MONDAY NIGHT
THROUGH FRIDAY...A PROGRESSIVE UPPER LEVEL RIDGE WILL REMAIN OVER
THE FORECAST AREA THROUGH TUESDAY...BRINGING DRY...SUNNY AND WARM
CONDITIONS. INLAND HIGHS WILL BE CREEPING UP INTO THE UPPER 80S
TUESDAY...BEFORE THE ECMWF AND GFS HAVE AN UPPER LEVEL TROUGH
ORIGINATING IN THE GULF OF ALASKA DRIFTING EASTWARD BY WEDNESDAY.
THIS WILL USHER IN A MARINE PUSH...COOLING TEMPERATURES OFF BACK TO
NEAR NORMAL FOR THE REMAINDER OF THE WORK WEEK. WILL SEE THE RETURN
OF MARINE STRATUS PUSHING INLAND ALONG THE COLUMBIA RIVER AND
THROUGH COASTAL GAPS OVERNIGHT...THEN AFTERNOON SUN. EXPECT A
STRONGER MARINE PUSH NEXT THURSDAY AND FRIDAY. /27 &&
.AVIATION...SHOWERS RETURN TODAY AS AN UPPER LEVEL SHORTWAVE MOVES
INTO THE AREA THIS MORNING AND LIFTS NORTH IN THE AFTERNOON.
EXPECT MVFR ON THE COAST WITH CIGS IN THE 1500-2500 FT RANGE
THROUGH THE MORNING...FOLLOWED BY SOME IMPROVEMENT LATER IN THE
AFTERNOON. INLAND AREAS GENERALLY VFR WITH AREAS OF MVFR THROUGH
MIDDAY. MVFR CIGS WILL PROBABLY BE IN THE 2000-3000 FT RANGE.
KPDX AND APPROACHES...EXPECT VFR TODAY AND TONIGHT. THERE ARE SOME
MVFR CIGS DEVELOPING OVER THE APPROACHES AT 10Z AND IT LOOK LIKE
IT WILL PROBABLY REACH KPDX AS WELL FOR SEVERAL HOURS THIS
MORNING. MORE ACTIVE SHOWERS LATER THIS MORNING AND AFTERNOON
COULD BRIEFLY BRING MVFR CIGS AS WELL.
&&
.MARINE...A LOW PRES CENTER WILL PERSIST NEAR THE NORTHERN B.C.
COAST THROUGH THE WEEKEND WITH A TROUGH EXTENDING TO THE PACNW.
WINDS SHOULD REMAIN BELOW 20 KT BUT TODAY THERE WILL PROBABLY BE
GUSTS 20 KT AS A WEAK TROUGH NEARS THE WATERS. HIGH PRESSURE AND
NORTHERLY WINDS WILL RETURN SUNDAY NIGHT AND PERSIST THROUGH NEXT
WEEK. THE PRESSURE GRADIENT WILL BE TIGHTEST TO THE SOUTH WHERE
WINDS WILL PERIODICALLY BLOW GREATER THAN 25 KT...ESPECIALLY IN
THE LATE AFTERNOONS AND EVENINGS.
STEEP SEAS WILL CONTINUE TONIGHT WITH OVERALL HEIGHTS DROPPING
AROUND 5 FEET THEN A W-NW SWELL WILL BUILD AND PEAK NEAR 9 FEET
SUNDAY. TJ/MH
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 8 AM PDT
THIS MORNING.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
Area Forecast Discussion
National Weather Service Spokane WA
230 AM PDT SAT JUN 28 2014
.SYNOPSIS...
Scattered rain showers and isolated thunderstorms will continue
over much of the region in some shape or form until Monday. Some
thunderstorms may produce heavy rainfall. A drying trend will
begin on Monday with more summer-like temperatures expected
through mid-week. The next round of showers and thunderstorms may
arrive by the end of the work week.
&&
.DISCUSSION...
Today through Sunday: The shortwave disturbance that produced the
thunderstorms yesterday is slowly shifting across eastern WA and
into the ID Panhandle at 2:00 AM. We are still hanging on to some
lingering showers with this wave over the basin, but the best mid
level instability and lift will be across the Panhandle through
the early morning. This is where I expect the heaviest rainfall
to occur and some lingering isolated thunderstorms to continue in
the morning. This system will shift into MT by the late morning
hours with some weak shortwave ridging building into the region by
the afternoon. Models do show drier air moving into the basin
today. This will result in much less instability over the basin
compared to yesterday and may result in a dry day for the Moses
Lake Area and much of the Upper Columbia Basin. Moisture is not
expected to mix out much across the mountains where dew points
will remain in the lower, including over the Okanogan Highlands,
Northeast Mtns and in the ID Panhandle. These areas will likely
see showers redevelop in the afternoon with isolated thunderstorms
possible. How much showers activity we see out in the Spokane
Area and on the Palouse is a tough call. I think the Spokane Area
will see a decent chance for showers in the afternoon due to the
fact that current dew points are in the mid 50s. Showers are
likely to be less prevalent further south for locations such as
Pullman/Moscow and the L-C Valley.
There is another shortwave trough of lower pressure approaching
the region in the eastern Pacific. This upper level disturbance is
located west of Vancouver Island at 130W. Forcing associated with
this wave will approach the Cascade Mtns in the afternoon, and
then spread across eastern WA and into the Panhandle overnight.
Best lift and precip chances will likely be across the northern
mtns. The cold pool associated with this final disturbance,
before the ridge builds in, will linger across the northeastern
portion of the forecast area on Sunday. This will result in more
scattered showers for Sunday afternoon primarily across the
northern mtns and in the ID Panhandle. Showers will be even less
likely across the basin, into the Spokane Area and down to the L-C
Valley for Sunday.
Temperatures over the weekend should rebound a little bit, but
will remain below seasonal normals. Expect high temperatures
generally in the mid 60s to upper 70s for most locations across
the Inland Northwest. /SVH
Sun Nt through Thurs: Following an isolated shower threat along
the Idaho/Montana border Sun Nt under unstable NW steering flow, a
quick transition to upper height rises/warming temps aloft will
commence as the next cool front approaches the Pac NW coast Tue.
The low-level thermal ridge (axis of warmest temps) also surges
north...with the warmest temps within this ridge peaking Tues and
Wed before a cool-down associated with the passage of the
aforementioned front Wed or Thurs. We have our lowest uncertainty
of the timing of this fropa for Thurs, with model guidance showing
quite a difference as far as how quickly east the front (and
cooler wx) advances across Ern Wa and N Id. For pcpn, we did not
make big changes to the fcst and kept the best chance for isolated
thunder limited to Wed- Thurs. Gusty winds along and near the E
Slopes of the Cascades will become a possible issue beginning as
early as Tues...then increasing Wed and Thurs as the marine
boundary lyr deepens across the interior of Wrn Oregon/Wa.bz
Thursday Night through Saturday night: A fairly benign far
extended forecast is in store for the Inland Northwest, including
the 4th of July Holiday. The ridge that will have brought very
warm temperatures mid week should shift east of the region, being
replaced by a trough sitting off the Pacific Northwest coastline.
Temperatures will be a degree or two cooler on Friday, with
similar temperatures on Saturday. Precipitation chances will be
kept to a minimum each day due to very dry low levels over most
locations. The exception may be over far southeast WA and adjacent
areas of the Idaho Panhandle on Friday. Some slightly better
moisture may advect into these areas, which, depending on timing,
could allow for some brief precipitation development. ty
&&
.AVIATION...
06Z TAFS: Not too much of a change to the synoptic setup keeping a
cool upper level trof containing a somewhat moist and unstable
airmass overhead. The same trof is steering a number of weather
disturbances in a southwest to northeast trajectory through it
over the aviation area of Northeast Washington and Northern for
the next 24 hours. MVFR ceilings seem to be the longest lingering
issue of note. Additionally any of the stronger pulse thunderstorms
that occur may bring some heavy rain and small hail. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 70 51 71 50 78 55 / 40 40 20 10 0 0
Coeur d`Alene 66 48 70 48 77 51 / 60 40 40 20 0 0
Pullman 69 48 69 45 76 48 / 30 10 10 0 0 0
Lewiston 76 55 77 53 83 56 / 20 10 10 0 0 0
Colville 70 48 72 48 83 52 / 70 60 40 20 0 0
Sandpoint 62 47 67 44 76 47 / 80 50 50 20 10 0
Kellogg 61 47 64 47 74 54 / 80 40 40 20 0 0
Moses Lake 81 54 80 54 86 56 / 20 10 0 0 0 0
Wenatchee 79 56 78 56 85 63 / 20 10 10 0 0 0
Omak 78 52 79 51 88 56 / 40 40 20 0 0 0
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
Area Forecast Discussion
National Weather Service Spokane WA
1040 PM PDT FRI JUN 27 2014
.SYNOPSIS...
Scattered rain showers and isolated thunderstorms will continue
over much of the region in some shape or form until Monday. Some
thunderstorms may produce heavy rainfall. Unsettled weather will
prevail into the weekend...especially for locations near the
Canadian border. A drying trend will begin on Monday with more
summer- like temperatures expected through mid- week. The next
round of showers and thunderstorms may arrive by the end of the
work week.
&&
.DISCUSSION...
A reminder: As the Spokane radar is still out for maintenance the
regional radar mosaic products will underdo their depiction of
shower and thunderstorm activity in the area. Have been relying on
IR satellite imagery, lightning detection equipment, and spotter
reports to fine tune what short term models like the HRRR have
been depiction this evening and overnight. Most of the coldest
cloud tops on IR satellite imagery associated with the more
intense shower and thunderstorms is up in extreme Northeast
Washington and North Idaho and working its way out. There are
still going to be showers in the area but their cloud tops are not
as high in comparison to those thunderstorms and as such are much
more difficult to pick out from the IR satellite imagery right
now. So until Monday this trofy active flow pattern sticks around
making it a cluttered and messy forecast this weekend. There seems
to be more potential for shortwave passage for the remainder of
tonight and for much of Saturday. The flow becomes a bit more
zonal rather than trofy Sunday which may mean a rain shadow
between the cascade crest higher terrain of North Idaho may have a
better chance of keeping the lowlands (including Spokane and Coeur
d` Alene) dry for most of Sunday but this is still not a certainty
with a flat zonal flow in place. What can be said now is that
ridge amplification indeed takes place Monday of next week and
rids the area of the active flow pattern which allows for a
considerably drier and warmer forecast in comparison to this
weekend. With so much going on there may not be much in a way of
an update to the text based products while short term grid
updates are more likely to occur.
/Pelatti
&&
.AVIATION...
06Z TAFS: Not too much of a change to the synoptic setup keeping a
cool upper level trof containing a somewhat moist and unstable
airmass ovehead. The same trof is steering a number of weather
disturbances in a southwest to northeast trajectory through it
over the aviation area of Northeast Washington and Northern for
the next 24 hours. MVFR ceilings seem to be the longest lingering
issue of note. Additionally any of the stronger pulse
thunderstorms that occur may bring some heavy rain and small hail.
/Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 52 71 51 71 50 77 / 60 40 30 20 10 0
Coeur d`Alene 52 68 48 70 48 75 / 70 50 40 20 20 0
Pullman 50 71 48 69 45 75 / 60 30 10 10 10 0
Lewiston 56 77 55 77 53 83 / 60 20 10 10 0 0
Colville 51 70 48 72 48 80 / 80 70 40 30 20 0
Sandpoint 52 64 47 67 44 75 / 80 90 50 30 20 10
Kellogg 49 62 47 64 47 73 / 80 80 30 20 20 0
Moses Lake 56 79 54 80 54 84 / 10 20 10 0 0 0
Wenatchee 58 78 56 78 56 85 / 10 20 10 0 0 0
Omak 53 77 52 79 51 85 / 20 30 10 10 10 0
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
955 PM CDT SUN JUN 29 2014
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
AND NEW INFORMATION ADDED TO UPDATE SECTION
.UPDATE...
ISSUED AT 942 PM CDT SUN JUN 29 2014
CAUTIOUSLY OPTIMISTIC THE WX SITN FOR OUR FCST AREA IS SETTLING
DOWN FOR THE NGT. NEED TO MAKE SURE THE SVR STORM COMING ESE ALONG
THE UPPER MICHIGAN BORDER REMAINS IN MI. IT APPEARS THAT WL
HAPPEN...BUT WL CONT TO MONITOR. THE STRONGEST CONVECTION COMING
OUT OF IA APPEARS DESTINED TO STAY TO OUR S.
CONVECTIVE POTENTIAL FOR TOMORROW CONTS TO BE DIFFICULT TO GET A
HANDLE ON WITH MUCH CONFIDENCE. THE NEW NAM IS OFF TO A HORRENDOUS
START WITH NO PCPN IN WI/IA/IL BTWN 00Z AND 03Z. IT GETS SOMETHING
GOING OVER SE WI BY MIDNIGHT...WHICH IS PROBABLY A REFLECTION OF
THE CURRENT ACTIVITY...THEN TAKES THAT OFF TO THE E LATER TNGT. IT
HAS HIGH DWPTS ACRS THE AREA TOMORROW...PRIOR TO GENERATING STG
CONVECTION...BUT IT SUFFERS FROM OBVIOUS FEEDBACK AT THAT TIME.
NOT SURE HOW USEFUL NAM FCST REALLY WILL BE. THE LATEST RAP SEEMS
UNDERDONE WITH CURRENT ACTIVITY ALSO...BUT IS AT LEAST BETTER THAN
THAN NAM. HOWEVER...IT SIGNIFICANTLY LOWERS DWPTS OVER THE AREA
MID-DAY TOMORROW...PROBABLY DUE TO MIXING. THAT WOULD SUGGEST SVR
THREAT WOULD REMAIN PRIMARILY TO OUR S.
UPDATED HWO TO REMOVE SVR RISK FM THE N FOR TNGT. DID NOT MAKE
ANY CHANGES FOR TOMORROW AS WE/LL NEED TO SEE HOW CURRENT
CONVECTION TO OUR S BEHAVES OVERNIGHT AND MAYBE WHERE WE ARE AT IN
TERMS OF MORNING CLOUDS TOMORROW BEFORE WE GET A BETTER FEEL FOR
WHAT WL HAPPEN IN THE AFTN.
&&
.SHORT TERM...TONIGHT AND MONDAY
ISSUED AT 238 PM CDT SUN JUN 29 2014
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW AN UPPER
LEVEL LOW SPINNING OVER LAKE WINNIPEG AND AN OCCLUDED FRONT BOWING
SOUTHWARD ACROSS MINNESOTA AND INTO NORTHWEST IOWA. AHEAD OF THIS
BOUNDARY IN A REGION OF MID-LEVEL CONVERGENCE...CLUSTERS OF SHOWERS
AND THUNDERSTORMS ARE MOVING ENE OVER NORTHERN IOWA. STORM MOTION
WOULD TAKE THE NORTHERN EDGE OF THIS CLUSTER OVER WAUSHARA AND
WINNEBAGO COUNTIES AFTER 4 PM IF THEY HOLD TOGETHER...WHICH IS NOT A
SURE BET. NOT EXPECTING ANYTHING SEVERE BY THE TIME THESE STORMS
ARRIVE. MEANWHILE FURTHER NORTH...SHORTWAVE ACTIVITY IS RIDING
WITHIN THE LEFT EXIT REGION OF A 90+ KT JET STREAK WHICH IS PUNCHING
INTO SOUTHERN MINNESOTA. A FEW SUPERCELLS DEVELOPED OVER NORTHWEST
WISCONSIN FROM THIS SHORTWAVE...ONE WHICH PROMPTED A SVR TSTORM
WARNING. ANOTHER WEAK IMPULSE IS UPSTREAM OVER CENTRAL
MINNESOTA...WHICH IS PROGGED TO ARRIVE LATER THIS AFTERNOON OVER N-C
WISCONSIN. WITH FURTHER DESTABILIZATION EXPECTED AHEAD OF THE
OCCLUDED FRONT ACROSS THE NORTH...A FEW STORMS COULD FIRE AFTER
22Z. IF STORMS DEVELOP...DAMAGING WINDS AND LARGE HAIL WILL BE
POSSIBLE DUE TO THE STRONG WIND FIELDS ALOFT. CONVECTION TRENDS ARE
THE MAIN FORECAST CONCERN.
TONIGHT...RATHER COMPLEX FORECAST TONIGHT THAT CONTINUES RIGHT INTO
MONDAY. CONVECTION OVER NORTHERN IOWA WILL BE HEADING TOWARDS THE
ROUTE 21 CORRIDOR EARLY THIS EVENING. OTHERWISE...A BEEFY 100 KT
JET STREAK WILL RESIDE FROM SOUTH DAKOTA TO SOUTHERN
WISCONSIN...PLACING THE LEFT FRONT QUAD ACROSS THE NORTHERN PART OF
THE BADGER STATE AT THE START OF THE EVENING. SHORTWAVE ACTIVITY
ROUNDING THE BASE OF THE UPPER LOW POSITIONED OVER LAKE WINNIPEG
WILL BE SWINGING THROUGH NORTHWEST WISCONSIN AT THE SAME TIME. IF
SUFFICIENT DESTABILIZATION TAKES PLACE SO A FEW STORMS
DEVELOP ACROSS N-C WISCONSIN...THINK ISOLATED TO SCATTERED
THUNDERSTORMS WILL CONTINUE THROUGH AT LEAST MID-EVENING. JUDGING
BY UPSTREAM ACTIVITY...SUPERCELLS WITH LARGE HAIL AND DAMAGING WINDS
WILL BE POSSIBLE. SOME OF THIS THUNDERSTORM ACTIVITY COULD SPREAD
SOUTHEAST INTO THE FOX VALLEY AND NORTHEAST WISCONSIN LATE IN THE
EVENING THOUGH FORCING WILL BE WEAKENING FARTHER SOUTHEAST. STORMS
SHOULD BE WEAKENING MID-EVENING ONWARD DUE TO NOCTURNAL
COOLING...BUT A FEW ELEVATED STORMS COULD TAP INTO 2000 J/KG OF
ELEVATED CAPE WHICH COULD BRING A LOW SEVERE CHANCE. THE UPPER JET
WILL BE SHIFTING NORTH OVERNIGHT WHICH WILL TAKE THE UPPER
DIVERGENCE WITH IT. MODELS INDICATE LITTLE TO NO CONVERGENCE ALONG
AN UPSTREAM COOL FRONT OVER THE NORTHERN MISSISSIPPI VALLEY SO ANY
LINGERING CONVECTION SHOULD CONTINUE TO WEAKEN OVERNIGHT.
REDUCED PRECIP CHANCES DUE TO THE UNCERTAINTY OF THE DEVELOPMENT AND
COVERAGE OF STORMS. MUGGY AND BREEZY NIGHT TIME LOWS IN THE MIDDLE
TO UPPER 60S.
MONDAY...WEAK UPSTREAM OCCLUDED FRONT WILL MOVE SLOWLY TO THE EAST INTO
CENTRAL WISCONSIN DURING THE AFTERNOON...PLACING EASTERN PORTIONS OF
THE STATE IN THE WARM SECTOR. ANTICIPATE AREAS OF LOW STRATUS OVER
PARTS OF THE AREA TO START THE MORNING. BUT WITH HEATING...MIXING
SHOULD YIELD AT LEAST PARTLY CLOUDY CONDITIONS BY MIDDAY. FURTHER
HEATING INTO THE LOWER TO MIDDLE 80S WILL YIELD 2000-3000 J/KG OF ML
CAPE DURING PEAK HEATING AND LITTLE TO NO CIN OVER EAST-CENTRAL WISCONSIN.
0-6KM BULK SHEAR WILL BE IN THE 40-50 KT RANGE WITH CURVED
HODOGRAPHS SUGGESTING A DISCRETE STORM MODE. FORCING VIA MID-LEVEL
HEIGHT FALLS AND WEAK SHORTWAVES ROUNDING THE BASE OF THE UPPER
TROUGH IS PROGGED TO ARRIVE LATE IN THE AFTERNOON. THESE CONDITIONS
SUPPORT A POTENTIAL FOR A SEVERE WEATHER EVENT LATE AFTERNOON ONWARD
OVER EAST-CENTRAL AND NORTHEAST WISCONSIN PENDING MORNING
CLOUDINESS/SHORTWAVE TIMING WHICH COULD DELAY THUNDERSTORM
FORMATION. THREATS WILL INCLUDE DAMAGING WINDS AND LARGE HAIL.
HIGHS IN THE LOWER TO MIDDLE 80S.
.LONG TERM...MONDAY NIGHT THROUGH SUNDAY
ISSUED AT 238 PM CDT SUN JUN 29 2014
THE SEVERE THUNDERSTORM AND HEAVY RAINFALL THREAT MONDAY EVENING
IS THE BIGGEST FCST CHALLENGE.
A WIDESPREAD SVR TSTM AND HEAVY RAINFALL THREAT OVER THE FOX
VALLEY/LKSHR ON MONDAY EVG AREAS LOOKS LIKE IT WILL BE CONTINGENT
UPON THE DEVELOPMENT AND MOVMT OF A SFC WAVE ALONG THE ADVANCING
COLD FRONT. THE ECMWF/GEM AND GFS ALL HAVE SOME SEMBLANCE OF A
SFC WAVE MOVG FROM FAR SW WI AT 00Z TO NE WI OR CENTRAL LK MICH BY
06Z...WITH STG 0-3 KM HELICITIES OF 300-400 MOVG THROUGH OUR SE
CWA DURING THE EVG HOURS. DEEP LAYER SHEAR OF 45 TO 60 KTS WILL BE
VERY FAVORABLE FOR SUPERCELLS AS WELL. STRONG UPPER LEVEL DIVG IN
THE RRQ OF A 100+ KT JET STREAK WILL COMBINE THE APPROACHING FRONT
AND A DEVELOPING LLJ TO PROVIDE PLENTY OF LIFT FOR TSTM
DEVELOPMENT. SBCAPE OF 1500-2000 J/KG IS EXPECTED OVER THE FOX
VALLEY EARLY IN THE EVG...ALONG WITH A VERY MOIST AIR MASS WITH
PWATS NEAR 2 INCHES AND H8 DEW POINTS OF +14 TO +18 C. HOWEVER...
THE NAM/SREF SUGGEST THAT THE SFC WAVE AND ASSOCIATED WARM FRONT
MAY GET HUNG UP NEAR THE IL/WI BORDER...AND FOCUS THE BEST SEVERE
WX AND HEAVY RAINFALL POTENTIAL OVER SOUTHERN WI. THESE
DIFFERENCES COULD MAKE THE DIFFERENCE BETWEEN A TORNADO OUTBREAK
ACROSS THE SE THIRD OF GRB CWA...OR A GLANCING BLOW WITH SOUTHERN
WI GETTING THE BRUNT OF THE ACTION. HAVE KEPT CATEGORICAL POPS
OVER OUR SE COUNTIES...TAPERING BACK TO LIKELY/CHC CATEGORIES
FARTHER NW. HAVE KEPT THE OVERNIGHT PERIOD DRY...ALTHOUGH WILL
NEED TO WATCH THIS...AS THE ECMWF HAS PCPN LINGERING IN NE WI
PAST MIDNIGHT.
AN UPPER LEVEL TROF AND ASSOCIATED NW CYCLONIC FLOW AT THE SFC
WILL KEEP SHOWERS IN THE FCST THROUGH WEDNESDAY AFTERNOON OR
EVENING...WITH CANADIAN HIGH PRESSURE BRINGING DRY CONDITIONS
ON THURSDAY AND FRIDAY. COOLER TEMPS WILL BE FELT DURING THIS
PERIOD.
MODELS DISAGREE ON HOW QUICKLY THE SFC HIGH WILL SHIFT EAST
LATER IN THE WEEK...WITH THE GEFS SLOWEST TO PULL THE HIGH
OUT OF THE WESTERN GREAT LAKES. OVERALL...EXPECT A SLIGHT
WARMING TREND INTO THE WEEKEND...WITH A SMALL CHANCE OF
TSTMS...ESPECIALLY IN OUR WESTERN AND NORTHERN COUNTIES.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 942 PM CDT SUN JUN 29 2014
MIXING INTO SLIGHTLY DRIER AIR ALOFT KNOCKED HUMIDITIES DOWN A
BIT TDA...AND SHOULD WORK AGAINST GETTING TOO MUCH FG FORMATION
OVERNIGHT. THE BULK OF THE SHRA/TSRA ACTIVITY THE REST OF THE
NIGHT IS LIKELY TO REMAIN TO OUR S. STILL A LOT OF QUESTIONS ABOUT
TOMORROW. WL MAKE ISSUANCE TIME DECISION ON WHETHER OR NOT RISK OF
STORMS IS GREAT ENOUGH TO WARRANT EXPLICIT INCLUSION OF THUNDER IN
THE LATTER PERIOD OF THE TAFS.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE.........SKOWRONSKI
SHORT TERM.....MPC
LONG TERM......KIECKBUSCH
AVIATION.......SKOWRONSKI
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
616 PM CDT SUN JUN 29 2014
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND MONDAY
ISSUED AT 238 PM CDT SUN JUN 29 2014
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW AN UPPER
LEVEL LOW SPINNING OVER LAKE WINNIPEG AND AN OCCLUDED FRONT BOWING
SOUTHWARD ACROSS MINNESOTA AND INTO NORTHWEST IOWA. AHEAD OF THIS
BOUNDARY IN A REGION OF MID-LEVEL CONVERGENCE...CLUSTERS OF SHOWERS
AND THUNDERSTORMS ARE MOVING ENE OVER NORTHERN IOWA. STORM MOTION
WOULD TAKE THE NORTHERN EDGE OF THIS CLUSTER OVER WAUSHARA AND
WINNEBAGO COUNTIES AFTER 4 PM IF THEY HOLD TOGETHER...WHICH IS NOT A
SURE BET. NOT EXPECTING ANYTHING SEVERE BY THE TIME THESE STORMS
ARRIVE. MEANWHILE FURTHER NORTH...SHORTWAVE ACTIVITY IS RIDING
WITHIN THE LEFT EXIT REGION OF A 90+ KT JET STREAK WHICH IS PUNCHING
INTO SOUTHERN MINNESOTA. A FEW SUPERCELLS DEVELOPED OVER NORTHWEST
WISCONSIN FROM THIS SHORTWAVE...ONE WHICH PROMPTED A SVR TSTORM
WARNING. ANOTHER WEAK IMPULSE IS UPSTREAM OVER CENTRAL
MINNESOTA...WHICH IS PROGGED TO ARRIVE LATER THIS AFTERNOON OVER N-C
WISCONSIN. WITH FURTHER DESTABILIZATION EXPECTED AHEAD OF THE
OCCLUDED FRONT ACROSS THE NORTH...A FEW STORMS COULD FIRE AFTER
22Z. IF STORMS DEVELOP...DAMAGING WINDS AND LARGE HAIL WILL BE
POSSIBLE DUE TO THE STRONG WIND FIELDS ALOFT. CONVECTION TRENDS ARE
THE MAIN FORECAST CONCERN.
TONIGHT...RATHER COMPLEX FORECAST TONIGHT THAT CONTINUES RIGHT INTO
MONDAY. CONVECTION OVER NORTHERN IOWA WILL BE HEADING TOWARDS THE
ROUTE 21 CORRIDOR EARLY THIS EVENING. OTHERWISE...A BEEFY 100 KT
JET STREAK WILL RESIDE FROM SOUTH DAKOTA TO SOUTHERN
WISCONSIN...PLACING THE LEFT FRONT QUAD ACROSS THE NORTHERN PART OF
THE BADGER STATE AT THE START OF THE EVENING. SHORTWAVE ACTIVITY
ROUNDING THE BASE OF THE UPPER LOW POSITIONED OVER LAKE WINNIPEG
WILL BE SWINGING THROUGH NORTHWEST WISCONSIN AT THE SAME TIME. IF
SUFFICIENT DESTABILIZATION TAKES PLACE SO A FEW STORMS
DEVELOP ACROSS N-C WISCONSIN...THINK ISOLATED TO SCATTERED
THUNDERSTORMS WILL CONTINUE THROUGH AT LEAST MID-EVENING. JUDGING
BY UPSTREAM ACTIVITY...SUPERCELLS WITH LARGE HAIL AND DAMAGING WINDS
WILL BE POSSIBLE. SOME OF THIS THUNDERSTORM ACTIVITY COULD SPREAD
SOUTHEAST INTO THE FOX VALLEY AND NORTHEAST WISCONSIN LATE IN THE
EVENING THOUGH FORCING WILL BE WEAKENING FARTHER SOUTHEAST. STORMS
SHOULD BE WEAKENING MID-EVENING ONWARD DUE TO NOCTURNAL
COOLING...BUT A FEW ELEVATED STORMS COULD TAP INTO 2000 J/KG OF
ELEVATED CAPE WHICH COULD BRING A LOW SEVERE CHANCE. THE UPPER JET
WILL BE SHIFTING NORTH OVERNIGHT WHICH WILL TAKE THE UPPER
DIVERGENCE WITH IT. MODELS INDICATE LITTLE TO NO CONVERGENCE ALONG
AN UPSTREAM COOL FRONT OVER THE NORTHERN MISSISSIPPI VALLEY SO ANY
LINGERING CONVECTION SHOULD CONTINUE TO WEAKEN OVERNIGHT.
REDUCED PRECIP CHANCES DUE TO THE UNCERTAINTY OF THE DEVELOPMENT AND
COVERAGE OF STORMS. MUGGY AND BREEZY NIGHT TIME LOWS IN THE MIDDLE
TO UPPER 60S.
MONDAY...WEAK UPSTREAM OCCLUDED FRONT WILL MOVE SLOWLY TO THE EAST INTO
CENTRAL WISCONSIN DURING THE AFTERNOON...PLACING EASTERN PORTIONS OF
THE STATE IN THE WARM SECTOR. ANTICIPATE AREAS OF LOW STRATUS OVER
PARTS OF THE AREA TO START THE MORNING. BUT WITH HEATING...MIXING
SHOULD YIELD AT LEAST PARTLY CLOUDY CONDITIONS BY MIDDAY. FURTHER
HEATING INTO THE LOWER TO MIDDLE 80S WILL YIELD 2000-3000 J/KG OF ML
CAPE DURING PEAK HEATING AND LITTLE TO NO CIN OVER EAST-CENTRAL WISCONSIN.
0-6KM BULK SHEAR WILL BE IN THE 40-50 KT RANGE WITH CURVED
HODOGRAPHS SUGGESTING A DISCRETE STORM MODE. FORCING VIA MID-LEVEL
HEIGHT FALLS AND WEAK SHORTWAVES ROUNDING THE BASE OF THE UPPER
TROUGH IS PROGGED TO ARRIVE LATE IN THE AFTERNOON. THESE CONDITIONS
SUPPORT A POTENTIAL FOR A SEVERE WEATHER EVENT LATE AFTERNOON ONWARD
OVER EAST-CENTRAL AND NORTHEAST WISCONSIN PENDING MORNING
CLOUDINESS/SHORTWAVE TIMING WHICH COULD DELAY THUNDERSTORM
FORMATION. THREATS WILL INCLUDE DAMAGING WINDS AND LARGE HAIL.
HIGHS IN THE LOWER TO MIDDLE 80S.
.LONG TERM...MONDAY NIGHT THROUGH SUNDAY
ISSUED AT 238 PM CDT SUN JUN 29 2014
THE SEVERE THUNDERSTORM AND HEAVY RAINFALL THREAT MONDAY EVENING
IS THE BIGGEST FCST CHALLENGE.
A WIDESPREAD SVR TSTM AND HEAVY RAINFALL THREAT OVER THE FOX
VALLEY/LKSHR ON MONDAY EVG AREAS LOOKS LIKE IT WILL BE CONTINGENT
UPON THE DEVELOPMENT AND MOVMT OF A SFC WAVE ALONG THE ADVANCING
COLD FRONT. THE ECMWF/GEM AND GFS ALL HAVE SOME SEMBLANCE OF A
SFC WAVE MOVG FROM FAR SW WI AT 00Z TO NE WI OR CENTRAL LK MICH BY
06Z...WITH STG 0-3 KM HELICITIES OF 300-400 MOVG THROUGH OUR SE
CWA DURING THE EVG HOURS. DEEP LAYER SHEAR OF 45 TO 60 KTS WILL BE
VERY FAVORABLE FOR SUPERCELLS AS WELL. STRONG UPPER LEVEL DIVG IN
THE RRQ OF A 100+ KT JET STREAK WILL COMBINE THE APPROACHING FRONT
AND A DEVELOPING LLJ TO PROVIDE PLENTY OF LIFT FOR TSTM
DEVELOPMENT. SBCAPE OF 1500-2000 J/KG IS EXPECTED OVER THE FOX
VALLEY EARLY IN THE EVG...ALONG WITH A VERY MOIST AIR MASS WITH
PWATS NEAR 2 INCHES AND H8 DEW POINTS OF +14 TO +18 C. HOWEVER...
THE NAM/SREF SUGGEST THAT THE SFC WAVE AND ASSOCIATED WARM FRONT
MAY GET HUNG UP NEAR THE IL/WI BORDER...AND FOCUS THE BEST SEVERE
WX AND HEAVY RAINFALL POTENTIAL OVER SOUTHERN WI. THESE
DIFFERENCES COULD MAKE THE DIFFERENCE BETWEEN A TORNADO OUTBREAK
ACROSS THE SE THIRD OF GRB CWA...OR A GLANCING BLOW WITH SOUTHERN
WI GETTING THE BRUNT OF THE ACTION. HAVE KEPT CATEGORICAL POPS
OVER OUR SE COUNTIES...TAPERING BACK TO LIKELY/CHC CATEGORIES
FARTHER NW. HAVE KEPT THE OVERNIGHT PERIOD DRY...ALTHOUGH WILL
NEED TO WATCH THIS...AS THE ECMWF HAS PCPN LINGERING IN NE WI
PAST MIDNIGHT.
AN UPPER LEVEL TROF AND ASSOCIATED NW CYCLONIC FLOW AT THE SFC
WILL KEEP SHOWERS IN THE FCST THROUGH WEDNESDAY AFTERNOON OR
EVENING...WITH CANADIAN HIGH PRESSURE BRINGING DRY CONDITIONS
ON THURSDAY AND FRIDAY. COOLER TEMPS WILL BE FELT DURING THIS
PERIOD.
MODELS DISAGREE ON HOW QUICKLY THE SFC HIGH WILL SHIFT EAST
LATER IN THE WEEK...WITH THE GEFS SLOWEST TO PULL THE HIGH
OUT OF THE WESTERN GREAT LAKES. OVERALL...EXPECT A SLIGHT
WARMING TREND INTO THE WEEKEND...WITH A SMALL CHANCE OF
TSTMS...ESPECIALLY IN OUR WESTERN AND NORTHERN COUNTIES.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 612 PM CDT SUN JUN 29 2014
MIXING INTO SLIGHTLY DRIER AIR ALOFT HAS KNOCKED HUMIDITIES DOWN A
BIT...AND SHOULD WORK AGAINST GETTING TOO MUCH FG FORMATION
OVERNIGHT. SHRA MAINLY OUT OF MID CLD DECK WL AFFECT THE CENTRAL
AND E-C WI TAF SITES THIS EVENING. MORE CELLULAR DEVELOPMENT IN NW
WI MAY AFFECT THE RHI AREA FOR A TIME. AFTER THAT...BEST GUESS IS
THAT SIG PCPN WL HOLD OFF UNTIL TOMORROW. BUT...WL NEED TO WATCH
CLOSELY ANY DEVELOPMENT THAT OCCURS IN IA TO MAKE SURE IT DOESN/T
CLIP THE C/E-C WI TAF SITES. SO CONFIDENCE IN DRY FCST NOT AS HIGH
AS IT COULD BE.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......KIECKBUSCH
AVIATION.......JS
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 243 PM CDT SAT JUN 28 2014
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW LOW
PRESSURE MOVING NORTH OVER THE NORTHERN PLAINS AND AN ASSOCIATED
COLD FRONT MOVING EAST OVER EASTERN SOUTH DAKOTA/NEBRASKA AND
KANSAS. STORMS HAVE BEGUN TO FIRE ALONG AN UPPER LEVEL FRONT OVER
MINNESOTA AND IOWA THAT IS OUTRUNNING THE SURFACE BOUNDARY. OVER
THE WESTERN GREAT LAKES...WEAK SHORTWAVE ENERGY IS MOVING NORTHWARD
OVER EASTERN WISCONSIN AND NORTHERN ILLINOIS/INDIANA AND IS
GENERATING ISOLATED SHOWERS AND STORMS OVER THE EASTERN PART OF THE
STATE. ANTICIPATE ISOLATED SHOWERS AND STORMS TO CONTINUE TO POP
UP THROUGH THE AFTERNOON AS THE ATMOSPHERE IS UNCAPPED. SEVERE
WEATHER IS NOT EXPECTED DUE TO VERY WEAK WIND FIELDS ALOFT...BUT
COULD SEE BRIEF HEAVY DOWNPOURS AND WIND GUSTS TO 40 MPH. AS THE
UPSTREAM FRONT DRAWS CLOSER TO THE REGION...THUNDERSTORM POTENTIAL
REMAINS THE MAIN FORECAST CONCERN.
TONIGHT...A SHORTWAVE TROUGH OVER THE CENTRAL PLAINS WILL PUSH THE
UPPER LEVEL FRONT TO THE NORTHEAST AND ACROSS THE STATE TONIGHT.
ISOLATED SHOWERS AND STORMS MAY CONTINUE INTO THE MIDDLE EVENING
HOURS OVER NORTHEAST WISCONSIN FROM THE WEAK SHORTWAVE ENERGY...BUT
THINKING THESE SHOWERS/STORMS SHOULD DIMINISH WITH LOSS OF SURFACE
HEATING. THEN ATTENTION WILL TURN TO A LINE OF STORMS ALONG THE
UPPER LEVEL FRONT FROM LATE EVENING ONWARD. THOUGH PWATS WILL BE
UPWARDS OF 1.75 INCHES...SURFACE BASED INSTABILITY WILL BE
DIMINISHING WITH TIME TONIGHT. PROGGED SOUNDINGS SHOW SUSTAINED
ELEVATED CAPES AROUND 500 J/KG DURING THIS PERIOD WHEN STORMS SHOULD
BE PUSHING THROUGH. WITH FORCING ON THE WEAKER SIDE AND EFFECTIVE
BULK SHEARS ONLY 15-20 KTS...AM THINKING THAT THE LINE OF STORMS
WILL BE WEAKENING AS THEY MOVE THROUGH THE AREA TONIGHT. HEAVY
RAINFALL WILL BE THE MAIN THREAT FROM THESE STORMS BUT THEY SHOULD BE
MOVING THROUGH AT A MODERATE CLIP THERE BY KEEPING THE EXCESSIVE
RAINFALL THREAT IN CHECK. MUGGY LOWS IN THE MIDDLE TO UPPER 60S.
SUNDAY...SHOWERS AND STORMS WILL CONTINUE OVER NE WISCONSIN UNTIL
THE UPPER FRONT CLEARS DOOR COUNTY...WHICH SHOULD OCCUR BY LATE
MORNING. THEREAFTER...AN UPPER LEVEL LOW WILL BE TAKING UP SHOP
OVER THE LAKE WINNIPEG REGION AS A BEEFY 100KT JET STREAK ROUNDS THE
BASE OF THE LOW. SHOULD SEE A PERIOD OF CLEARING TAKE PLACE FROM
MID-MORNING ONWARD AS DRIER AIR MOVES IN FROM THE SOUTHWEST. THE
CLEARING SKIES WILL SERVE TO DESTABILIZE THE ATMOSPHERE THROUGH PEAK
HEATING AHEAD OF A STALLED SURFACE BOUNDARY OVER EASTERN MINNESOTA.
WITH THE POSSIBILITY OF SHORT WAVE ENERGY ACCOMPANYING THE JET
STREAK...WILL START RAMPING UP THE SHOWER AND STORM THREAT BY
MID-AFTERNOON. LOW LEVEL TEMPS WILL BE WARMER TOMORROW AFTERNOON
COMPARED TO TODAYS READINGS...SO BOOSTED UP MAXES A COUPLE DEGREES.
ML CAPES SHOULD STILL REMAIN IN THE 1500-2000 J/KG RANGE BUT 0-6KM
BULK SHEARS WILL INCREASE WITH THE ARRIVAL OF THE JET STREAK TO 35-45
KNOTS. IF ANY WEAK SHORTWAVE IMPULSE CAN GENERATE A FEW
STORMS...SEVERE WEATHER WILL BE POSSIBLE DUE TO THE STRONG WIND
FIELDS. A DISCRETE STORM MODE WILL BE LIKELY WITH ANY
STORMS...WHICH WOULD BE CAPABLE OF PRODUCING LARGE HAIL...DAMAGING
WINDS...AND A TORNADO. AT THIS TIME...THINKING ISOLATED TO LOW
END SCATTERED COVERAGE LATE TOMORROW AFTERNOON. HIGHS IN THE MIDDLE
TO UPPER 80S.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 243 PM CDT SAT JUN 28 2014
SEVERE TSTM AND HEAVY RAINFALL POTENTIAL SUNDAY NIGHT THROUGH MONDAY
EVENING...AND A RETURN TO COOLER TEMPERATURES DURING THE NEXT WORK
WEEK...ARE THE MAIN FCST CONCERNS.
LATEST MODEL RUNS SUGGEST THAT SCATTERED SEVERE CONVECTION MAY BE
ONGOING OVER THE NW HALF OF THE CWA BY EARLY SUNDAY EVENING...AIDED
BY THE TAIL END OF A S/W TROF...A JET STREAK...STRONG INSTABILITY
AND DEEP LAYER SHEAR OF 50-60 KTS. GIVEN THE DEGREE OF WIND
SHEAR...SUPERCELLS OR BOWING LINE SEGMENTS ARE EXPECTED. THIS
ACTIVITY SHOULD GRADUALLY SHIFT EAST OVERNIGHT...AND BE SUSTAINED
BY THE RRQ OF AN UNSEASONABLY STRONG UPPER LEVEL JET. HAVE GONE
WITH HIGH-END CHANCE OR LOW-END LIKELY POPS...DUE TO UNCERTAINTIES
IN LOCATION AND TIMING. WITH H8 DEW POINTS INCREASING TO +12 TO
+16 C AND K-INDICES OF 35 TO 40... LOCALLY HEAVY RAINFALL IS
ALSO ANTICIPATED.
ON MONDAY...MODELS DEPICT A GENERAL LULL IN THE CONVECTION DURING
THE MORNING...ALLOWING THE ATMOSPHERE TO RECHARGE AHEAD OF AN
APPROACHING COLD FRONT. EXPECT SEVERE CONVECTION TO FIRE AGAIN
ALONG AND AHEAD OF THE COLD FRONT AS IT MOVES THROUGH C/NE WI
MONDAY AFTERNOON AND EVENING. ONCE AGAIN...THE TSTM ACTIVITY WILL
BE AIDED BY STRONG UPPER LEVEL DIVG WITH THE RRQ OF A 100 KT JET
STREAK. MODELS HAVE SOME CRITICAL DIFFERENCES...WHICH WILL HAVE
A HIGH IMPACT ON THE FCST. FIRST OF ALL...THE ECMWF IS SLOWER
WITH THE ARRIVAL OF THE HEAVIER PCPN...DELAYING IT UNTIL MONDAY
EVENING...WHILE THE GEM/GFS BRING A BULLSEYE INTO THE RGN MONDAY
AFTERNOON. ANOTHER KEY FEATURE IS THE PRESENCE OF A SFC LOW
RIPPLING NE ALONG THE FRONTAL BOUNDARY ON THE ECMWF/NAM MODEL RUNS.
IF THIS OCCURS...LOW-LEVEL SHEAR WILL BECOME MUCH MORE FAVORABLE
FOR TORNADO DEVELOPMENT. WITH PWATS INCREASING TO 2 INCHES AHEAD
OF THE FRONT...HEAVY RAINFALL IS AN OBVIOUS CONCERN.
WILL ISSUE AN ESF TO ADDRESS THE HYDRO CONCERNS FOR SUNDAY NIGHT
THROUGH MONDAY EVENING.
THE COLD FRONT WILL SHIFT EAST OF THE REGION LATE MONDAY EVENING...
ALLOWING PCPN TO END AFTER MIDNIGHT. A SECONDARY COLD FRONT AND
S/W TROF WILL ARRIVE ON TUESDAY...RESULTING IN SCT SHRA/ISOLD
TSRA. PCPN CHANCES WILL LINGER INTO MIDWEEK...AS THE UPPER
LEVEL TROF AXIS SLOWLY MOVES THROUGH THE REGION. THE ECMWF
ACTUALLY HAS SOME SIGNIFICANT PCPN OVER THE FA ON WEDS NGT...
BUT WILL WAIT TO SEE ANOTHER COUPLE MODEL RUNS BEFORE JUMPING ON
THAT TREND.
CANADIAN HIGH PRESSURE WILL BRING MAINLY DRY CONDITIONS FROM
THURSDAY INTO FRIDAY...WITH DEVELOPING RETURN FLOW BRINGING
A CHANCE OF TSTMS AGAIN BY THE WEEKEND.
TEMPERATURES WILL START OFF WARM AND MUGGY SUNDAY NIGHT INTO
MONDAY...THEN DROP BLO NORMAL FOR MUCH OF THE WORK WEEK. A
RETURN TO NORMAL READINGS IS EXPECTED BY FRIDAY/SATURDAY.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1205 PM CDT SAT JUN 28 2014
WEAK DISTURBANCE LIFTING NORTHWARD ACROSS EASTERN WISCONSIN COMBINED
WITH DAYTIME INSTABILITY WILL LEAD TO ISOLATED TO SCATTERED THUNDERSTORM
DEVELOPMENT THIS AFTERNOON. MAINLY THINKING STORMS WILL OCCUR EAST
OF THE INTERSTATE 39/US 51 CORRIDOR. ONCE THE DISTURBANCE EXITS
EARLY THIS EVENING...CIGS WILL BE SLOWLY FALLING DUE TO A HUMID
AIRMASS IN PLACE. THE NEXT ROUND OF STORMS WILL ARRIVE OVERNIGHT
AHEAD OF THE NEXT DISTURBANCE. AM THINKING THE STORMS WILL BE
WEAKENING AS THEY MOVE EAST ACROSS THE REGION BEFORE EXITING
NORTHEAST WISCONSIN BETWEEN 12-15Z. IFR/MVFR CIGS/VSBYS CAN BE
EXPECTED WITHIN ANY STORMS. CLEARING SKIES AFTER 15Z THROUGH THE
END OF THE TAF PERIOD.
&&
.MARINE...
ISSUED AT 243 PM CDT SAT JUN 28 2014
VISIBLE SATELLITE IMAGERY SHOWS AREAS OF DENSE FOG
OFFSHORE FROM CENTRAL WISCONSIN TO CENTRAL DOOR COUNTY. DUE TO
JUICY AIR FLOWING OVER THE COLDER WATERS...DENSE FOG WILL BE
POSSIBLE ALONG THE LAKE MICHIGAN SHORELINE THROUGH AT LEAST TOMORROW
NIGHT AND POSSIBLY INTO MONDAY. WILL KEEP THE DENSE FOG ADVISORY
GOING THROUGH TOMORROW AFTERNOON FOR STARTERS. BUT DESPITE THE
ONSHORE FLOW...NO BEACH HAZARD STATEMENT WILL BE ISSUED DUE TO THE
FOG AND COLD WATERS.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......KIECKBUSCH
AVIATION.......MPC
MARINE.........MPC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
152 PM CDT SAT JUN 28 2014
.SHORT TERM...(TONIGHT THROUGH SUNDAY NIGHT)
ISSUED AT 152 PM CDT SAT JUN 28 2014
SEVERE THREAT INCLUDING HEAVY RAINFALL REMAIN THE MAIN CONCERN
THROUGH THE REST OF THIS WEEKEND.
WATER VAPOR LOOP AND RAP ANALYSIS HAS A NEGATIVELY TILTED MID-LEVEL
TROUGH/WEAK SURFACE COLD FRONT EXTENDING FROM WESTERN ND THROUGH THE
CENTRAL PLAINS. FEED OF MOISTURE TRANSPORT AHEAD OF THE TROUGH WAS
PRODUCING SEVERAL LINES OF SHOWERS/THUNDERSTORMS ACROSS MN/IA...AND
INTO THE CENTRAL PLAINS. OTHERWISE...A WARM AND MUGGY AIRMASS WAS IN
PLACE ACROSS THE AREA WITH TEMPERATURES IN THE LOWER 80S AND DEW
POINTS IN THE UPPER 60S TO THE LOWER 70S.
WILL BE WATCHING THE PROGRESSION OF THE MID-LEVEL TROUGH/WEAK
SURFACE COLD FRONT AND CONVECTION THROUGH THE REST OF THIS AFTERNOON
INTO TONIGHT. CONSENSUS OF MESO-WRF MODELS CONTINUE TO ENHANCE
THUNDERSTORM ACTIVITY ALONG AND AHEAD OF THIS TROUGH/FRONT AS IT
MOVES INTO THE AREA LATE THIS AFTERNOON/EARLY EVENING. NAM 0-1KM
MLCAPE IN THE 500-1000J/KG RANGE WITH 0-3KM BULK SHEAR AROUND 20KT.
MEANWHILE... PRECIPITABLE WATER VALUES APPROACHING 2 INCHES.
SO...INGREDIENTS ARE THERE FOR PERHAPS SOME ORGANIZED LINE/S OF
THUNDERSTORMS MOVING INTO THE AREA LATE THIS AFTERNOON AND EARLY
EVENING WITH THE MAIN IMPACT BEING BOUTS OF HEAVY RAINFALL AND
POTENTIAL FOR DAMAGING WINDS. RAP ALSO SHOWING SOMEWHAT ENHANCED NON-
TORNADIC SUPERCELL SIGNATURE FOR PERHAPS A BRIEF SPIN-UP OF AN
ISOLATED TORNADO OR TWO ON THE LEADING EDGE OF THE LINE/S OF
CONVECTION. APPEARS RIGHT NOW THE MAIN SEVERE THREAT WILL BE IN THE
4-10 PM TIME FRAME. APPEARS THE TROUGH AND BULK OF THE
SHOWER/THUNDERSTORMS WILL EXIT THE AREA AFTER MIDNIGHT.
ON SUNDAY...AFTER A BRIEF MORNING LULL IN THE ACTION...PLAN ON
ANOTHER ROUND OF THUNDERSTORMS TO MOVE BACK INTO THE AREA MAINLY
LATER IN THE AFTERNOON INTO SUNDAY NIGHT AS ANOTHER MID-LEVEL TROUGH
INTERACTS WITH THE SURFACE FRONTAL BOUNDARY LAID OUT ACROSS SOUTHERN
WI THROUGH CENTRAL IA. THERE WILL BE AMPLE 0-3KM BULK SHEAR IN THE
30-35KT RANGE AND MUCAPE IN THE 1800-2500J/KG GOING INTO SUNDAY
EVENING FOR A ANOTHER POTENTIAL FOR ORGANIZED LINES OF THUNDERSTORMS
WITH DAMAGING WINDS AND HEAVY RAINFALL. MID-LEVELS WILL ALSO BE IN
COOLING MODE FOR STEEPER LAPSE RATES AND LARGE HAIL POTENTIAL.
ALSO...CANNOT RULE OUT A BRIEF TORNADO OR TWO AS WELL.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 152 PM CDT SAT JUN 28 2014
ANOTHER ROUND OF SEVERE WEATHER/HEAVY RAINFALL LIKELY MONDAY.
MODELS HAVE BEEN COMING INTO BETTER AGREEMENT IN GENERATING A MID-
LEVEL WAVE OVER THE CENTRAL PLAINS AND RACING ITO NORTHEAST ACROSS
THE STALLED OUT BOUNDARY RUNNING FROM SOUTHERN WI INTO CENTRAL IA.
MODEL CONSENSUS 0-3KM MUCAPE RUNNING SOMEWHERE AROUND 1200J/KG
ALONG/NORTH OF I-94...TO NEAR 3000J/KG ACROSS NORTHEAST IA. THE NAM
IS THE MOST BALLISTIC WITH CAPE NEARING 5500J/KG BY AFTERNOON ACROSS
NORTHEAST IA. NAM/GFS/ECMWF ALL INDICATING AMPLE 0-3KM BULK SHEAR IN
THE 35-55KT RANGE. SO...LOOKS LIKE ANOTHER SHOT FOR SEVERE
THUNDERSTORMS WITH HEAVY RAINFALL. TORNADO/LARGE HAIL THREAT ALSO
LOOKS HIGHER FOR PORTIONS OF SOUTHWEST WI INTO NORTHEAST IA WHERE
NAM INDICATES STORM RELATIVE HELICITY VALUES IN THE 500-700 RANGE.
LOOK FOR THE BULK OF THIS CONVECTION TO PUSH EAST OF THE AREA DURING
THE MID-LATE EVENING HOURS.
FOR TUESDAY THROUGH THURSDAY...GFS/ECMWF INDICATING COOLER/CYCLONIC
FLOW DOMINATING THE REGION. TUESDAY LOOKS PRIME FOR SOME INSTABILITY
SHOWERS/ISOLATED THUNDERSTORMS MAINLY TUESDAY AFTERNOON WITH COLDEST
POOL OF AIR ALOFT.
FOR FRIDAY/SATURDAY...SOME DIFFERENCES BETWEEN THE ECMWF/GFS ARISE
AS THE ECMWF BUILDS A FLAT RIDGE INTO THE REGION WHILE THE GFS
MAINTAINS COOLER/BROAD CYCLONIC FLOW. EITHER WAY...LOOKS LIKE A
COUPLE ROUNDS OF SHOWERS/THUNDERSTORMS WILL BE POSSIBLE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1205 PM CDT SAT JUN 28 2014
UPPER LEVEL SHORTWAVE TROUGH SLATED TO DRIVE EAST/NORTHEAST ACROSS
THE REGION TONIGHT...AND WILL SERVE AS THE MAIN FOCUS FOR A LINE OF
TSRA/SHRA THAT WILL IMPACT KRST/KLSE BETWEEN 22-03Z. EXPECTING
IFR/MVFR CONDITIONS WITH THE STORMS...ALONG WITH THE LIKELIHOOD OF
ENHANCED WINDS. VERY HEAVY RAIN WILL ALSO ACCOMPANY THE STRONGER
STORMS. MOST OF THE ACTIVITY WILL HAVE MOVED EAST BY 03Z...WITH SOME
LINGERING SHOWERS POSSIBLE INTO THE EARLY OVERNIGHT. MODELS THEN
HINT THAT LOW STRATUS COULD AGAIN DEVELOP UNDER THE LOW LEVEL
INVERSION TOWARD 12Z ON SUN - SIMILAR TO WHAT OCCURRED THIS MORNING.
LOOKS REASONABLE ENOUGH TO ADD TO THE FORECAST AT THIS TIME...BUT
WILL NEED TO EVALUATED LATER TO SEE IF THE POTENTIAL IS STILL
PROBABLE.
&&
.HYDROLOGY...
ISSUED AT 152 PM CDT SAT JUN 28 2014
PLAN ON PERIODS OF HEAVY RAINFALL THROUGH THE REST OF THE WEEKEND
AND AGAIN ON MONDAY AS SEVERAL ROUNDS OF THUNDERSTORMS ARE FORECAST
TO MOVE THROUGH. DUE TO MOSTLY TRANSITORY NATURE OF THE
CONVECTION...FLASH FLOODING WILL LIKELY END UP BEING MORE OF A
LOCALIZED THREAT. HOWEVER...IF TRAINING OCCURS...HEAVY RAINFALL
COULD BE PROBLEMATIC. THIS COULD BE THE ISSUE MORE ON MONDAY. WILL
HAVE TO WATCH EVOLUTION OF THIS ACTIVITY AND POTENTIAL FOR A FLASH
FLOOD WATCH
PLAN ON THE MAIN STEM OF THE MISSISSIPPI TO REMAIN HIGH THROUGH NEXT
WEEK DUE TO ADDITIONAL RAINFALL THROUGH MONDAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...RIECK
HYDROLOGY...DAS
AREA FORECAST DISCUSSION
NWS ALBANY NY
515 AM EDT MON JUN 30 2014
.SYNOPSIS...
HIGH PRESSURE OFFSHORE WILL TRANSFORM INTO A BERMUDA HIGH. A WEAK
WARM FRONT CROSSING THE REGION TODAY WILL BRING SOME WIDELY
SCATTERED SHOWERS AND MAYBE A THUNDERSTORM. IT WILL THEN TURN MORE
HUMID AND HOT MID WEEK WITH SCATTERED MAINLY AFTERNOON
THUNDERSTORMS. WHILE MOST OF THE TIME WILL BE RAINFREE ANY
THUNDERSTORM THAT DEVELOPS COULD CONTAIN HEAVY RAINFALL AND GUSTY
WINDS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 500 AM EDT...A BROKEN LIGHT OF SHOWERS HAS WORKED INTO THE
NORTHWESTERN AREAS OF OUR FORECAST AREA...NAMELY THE ADIRONDACK
PARK. WE HAVE NOT SEEN A SINGLE CLOUD TO LIGHTNING STRIKE ON OUR
WATCH AND THEREFORE FOR NOW...WILL JUST CALL IT SHOWERS. (THE RUC13
INDICATED NO REAL INSTABILITY THROUGH THE EARLY MORNING HOURS).
THE LINE OF SHOWERS WAS THE RESULT OF A SECONDARY WARM
FRONT...REALLY MORE LIKE A DEWPOINT DISCONTINUITY LINE OVER CENTRAL
NEW YORK. DEWPOINTS ON THE EAST SIDE OF THIS BOUNDARY WERE STILL
GENERALLY IN THE 50S...AND IN SOME CASES...FALLING. TO THE WEST OF
THIS BOUNDARY...THEY HAD RISEN WELL INTO THE 60S.
THE 06Z HRRR STILL INDICATED SHOWER AND AFTERNOON THUNDERSTORM
ACTIVITY VERY RANDOMLY DISTRIBUTED OVER THE REGION...MAINLY WEST OF
THE HUDSON VALLEY...WHERE INSTABILITY LOOKS TO BE A LITTLE
BETTER...AS OPPOSED TO FURTHER EAST. UP TO 1000 J/KG OF INSTABILITY
IS POSSIBLE WEST OF THE HUDSON VALLEY. WE HAVE WE PLACED 40 POPS TO
THE NW OF THE CAPITAL REGION...30 CAPITAL REGION...ONLY 20 (LATE)
FURTHER SOUTH AND EAST.
DUE TO A LITTLE MORE IN THE WAY OF CLOUDS AND THE FRONT
NEARBY...TEMPERATURES TODAY COULD ACTUALLY BE A POINT OR TWO LOWER
THAN YESTERDAY BUT HUMIDITY WILL BEGIN TO CREEP UPWARD.
A SOUTH WIND WILL PREVAIL 5 TO 15 MPH TODAY. LOOK FOR HIGHS IN THE
MID 80S MOST VALLEY LOCATIONS...CLOSER TO 80 HIGHER TERRAIN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
ANY THUNDERSTORM ACTIVITY SHOULD DWINDLE THIS EVENING WE LOOSE THE
HEATING. ALSO...THE AFOREMENTIONED WARM FRONT WILL LIKELY HAVE MOVED
TO OUR EAST BY THEN.
WE WILL ULTIMATELY BE LEFT WITH A MUGGY SOMEWHAT HAZY NIGHT. A SOUTH
WIND WILL CONTINUE 5-10 MPH. OVERNIGHT LOWS WILL BE IN THE MID TO
UPPER 60S.
TUESDAY LOOKS TO BE A HOT ONE. BERMUDA HIGH OFFSHORE WILL PUMP A
SOUTHWEST FLOW OUR WAY. THIS FLOW WILL SEND H850 TEMPERATURES TO
NEAR 20C ACROSS MUCH OF OUR REGION. DEWPOINTS WILL CLIMB WELL INTO
THE 60S. WITH A GOOD DEAL OF HAZY SUNSHINE...THIS WILL TRANSLATE TO
SURFACE TEMPERATURES HITTING CLOSE TO 90 DEGREES IN VALLEY
LOCATIONS...LOWER TO MID 80S HIGHER TERRAIN.
THE DAY WILL START OUT MAINLY RAINFREE. HOWEVER...INSTABILITY LOOKS
TO RAMP UP TO WELL OVER 1500 J/KG DURING THE AFTERNOON. THIS COULD
BE ENOUGH INSTABILITY WHEN COMBINED WITH A VERY WEAK DISTURBANCE
SPARKED BY AN UPSTREAM TROUGH...TO PRODUCE WIDELY SCATTERED
THUNDERSTORMS DURING THE AFTERNOON. WHILE COVERAGE OF THE
THUNDERSTORMS LOOKS WIDELY SCATTERED...ANY THUNDERSTORM THAT DOES
FORM AS A SLIGHT CHANCE OF PRODUCING GUSTY WINDS AND HEAVY
RAINFALL...AND COULD PULSE BRIEFLY TO SEVERE LIMITS...MAINLY WIND
DAMAGE.
THUNDERSTORMS WILL DIMINISH AGAIN TUESDAY NIGHT AS ONCE AGAIN IT
WILL BE QUITE MUGGY. OVERNIGHT LOWS WILL LIKELY STAY AT OR ABOVE 70
IN THE HUDSON VALLEY FROM THE CAPITAL REGION SOUTHWARD...LOWER TO
MID 60S HIGHER TERRAIN.
WEDNESDAY WILL BE HOT AGAIN. THIS TIME HOWEVER...A COLD FRONT WILL
BE APPROACHING FROM THE NORTHWEST. EITHER THE FRONT...OR MORE LIKELY
A PRE-FRONTAL TROUGH LOOKS TO BE FOCUS FOR ANY CONVECTION THAT
DEVELOPS MAINLY DURING THE AFTERNOON. WE HAVE INCREASED POPS TO 50
DURING THE AFTERNOON.
DEPENDING ON HOW MUCH SUNSHINE WE RECEIVE TEMPERATURES COULD ONCE
AGAIN HIT 90 OR A LITTLE HIGHER ACROSS THE HUDSON VALLEY...MID OR
UPPER 80S ELSEWHERE ACROSS THE REGION. WE EXPECT MORE SUNSHINE THAN
CLOUDS...AT LEAST THROUGH THE TIME OF THE PEAK HEATING.
THE COLD FRONT (OR FRONTS) WILL SLOWLY MOVE THROUGH WEDNESDAY NIGHT
SO SHOWERS AND THUNDERSTORM ACTIVITY SHOULD CONTINUE. OVERNIGHT LOWS
WILL COOL TO THE 50S ACROSS THE ADIRONDACKS PARK WHERE THE FRONT IS
FORECAST TO MOVE THROUGH. FURTHER SOUTH...LOWS WILL GENERALLY
REMAIN IN THE 60S.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
MOST OF THE ATTENTION THIS UPCOMING LONG TERM PERIOD WILL BE WHAT IF
ANY IMPACTS WILL OCCUR ACROSS THE CWFA FROM THE DEVELOPING TROPICAL
ENTITY OFF THE SOUTHEAST COAST. LATEST GLOBAL MODELS CONTINUE TO
SUGGEST THIS TROPICAL ENTITY WILL TRACK OFF THE ATLANTIC COAST.
HOWEVER...THIS IN TURN MAY HAVE AN IMPACT WITH A SLOWER COLD FRONTAL
PASSAGE FORECAST ON THURSDAY. FURTHERMORE...WHILE STILL QUITE EARLY
IN THE FORECAST PROCESS...A POTENTIAL "PRE" EVENT MAY UNFOLD FOR
PORTIONS OF OUR REGION. GIVEN THE UNCERTAINTY...WE WILL HOLD ONTO
AND EXPAND A BIT THE POPS/WX GRIDS THROUGH MOST OF THURSDAY INTO
THURSDAY NIGHT. GUIDANCE NUMBERS DO LOOK A LITTLE HIGH GIVEN THE
EXPECT CLOUD COVER AND THE CHANCE FOR PRECIP AS WE WILL SHADE
SLIGHTLY COOLER PER THE WPC/ECMWF NUMBERS.
THEREAFTER...A BROAD ANTICYCLONIC FLOW /SURFACE HIGH/ SLOWLY BUILDS
ACROSS THE REGION INDEPENDENCE DAY AND INTO THE HOLIDAY WEEKEND.
THIS COULD BRING ABOUT THE FIFTH CONSECUTIVE DRY WEEKEND TO THE
REGION AS SUBSIDENCE INCREASES IN THE WAKE OF THE COASTAL EVENT AND
RISING HEIGHTS ALOFT. AS SUNSHINE INCREASES...SO TOO WILL BE THE
SURFACE TEMPERATURES WITH MAINLY LOWER HALF OF THE 80S FOR AFTERNOON
HIGHS AND OVERNIGHT LOWS INTO THE 50S AND LOWER 60S.
&&
.AVIATION /08Z MONDAY THROUGH FRIDAY/...
MAINLY SKC/CLR ACROSS THE TAF LOCATIONS...HOWEVER...AS SEEN IN THE
SATELLITE IMAGERY THERE WILL BE AN INCREASE IN HIGH AND MID LEVEL
CLOUDS OVERNIGHT. THIS WILL ALSO RESULT IN A LOWER PROBABLY FOR
FOG FORMATION AS WE WILL PLACE A VCFG/MIFG IN THE TAFS /WITH THE
EXCEPTION OF KALB/. A LIGHT SOUTHERLY WIND THE REMAINDER OF THE
OVERNIGHT LESS THAN 5KTS. AS FOR SHOWER POTENTIAL...EXPECTATIONS
REMAIN ALONG A WEAKENING TREND AS THIS ACTIVITY TRACKS EASTS.
A MAINLY CLOUDY...VFR...START DAYLIGHT MONDAY MORNING AS WEAK FRONT
MOVES ACROSS THE REGION. THE CHANCE FOR SHOWERS REMAINS LOW AS WE
WILL CONTINUE WITH A VCSH AT THIS TIME. THOSE CLOUDS ARE EXPECTED
TO BREAK UP BY AFTERNOON. A LIGHTLY SOUTHERLY WIND AT 10KTS OR LESS
ARE EXPECTED.
INCREASING LOW LEVEL MOISTURE WILL ALLOW FOR BR/HZ TO DEVELOP MONDAY
EVENING AND MAY POSE A THREAT FOR MVFR/IFR CONDITIONS LATER MONDAY
NIGHT.
OUTLOOK...
MON NIGHT: LOW OPERATIONAL IMPACT. PATCHY FG.
TUE-WED NIGHT: MODERATE OPERATIONAL IMPACT.BREEZY CHANCE OF
SHRA...TSRA. THU: HIGH OPERATIONAL IMPACT. LIKELY SHRA...TSRA.
THU NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
INDEPENDENCE DAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
&&
.FIRE WEATHER...
MOST AREAS DID NOT SEE A FULL RECOVERY OVERNIGHT DUE TO A BREEZE AND
HIGH CLOUDS. HOWEVER...RH VALUES WILL REMAIN SLIGHTLY ELEVATED
THROUGHOUT THE DAY...BOTTOMING OUT AROUND 50 PERCENT. THERE WILL BE
MORE CLOUDS THAN YESTERDAY ALONG WITH WIDELY SCATTERED SHOWERS AND
MAYBE AN AFTERNOON THUNDERSTORM AROUND BUT MOST AREAS WILL LIKELY
NOT PICK UP A QUARTER OF AN INCH.
A NEARLY FULL RECOVERY LIKELY TONIGHT AS IT WILL BE MORE HUMID AND
THE BREEZE ONLY SLIGHT.
HOT TUESDAY WITH MOST VALLEY AREAS APPROACHING OR EVEN ECLIPSING 90
DEGREES. AFTERNOON RH VALUES WILL AROUND 50 PERCENT ONCE MORE.
A SOUTH TO SOUTHWEST WIND WILL INCREASE TO 10-15 MPH...WITH SOME
AFTERNOON GUSTS TO 25 MPH ON TUESDAY.
AFTERNOON THUNDERSTORMS ARE POSSIBLE ONCE MORE ON...MAINLY WEST OF
THE HUDSON VALLEY ON TUESDAY.
MORE THUNDERSTORMS POSSIBLE ALONG WITH HOT AND HUMID WEATHER FOR
WEDNESDAY. HOWEVER...A COLD FRONT WILL LIKELY WORK THROUGH WEDNESDAY
NIGHT...STALLING JUST SOUTH OF OUR REGION ON THURSDAY.
&&
.HYDROLOGY...
NO HYDRO PROBLEMS EXPECTED TODAY.
THERE WILL LIGHT SHOWERS AROUND THIS MORNING AND THE POSSIBILITY OF
WIDELY SCATTERED AFTERNOON THUNDERSTORMS. THESE DO NOT LOOK TO
PRODUCE AVERAGE BASIN RAINFALLS OF A QUARTER OF AN INCH OR MORE.
MORE ROBUST THUNDERSTORMS ARE POSSIBLE TUESDAY...MAINLY WEST OF THE
HUDSON VALLEY. SOME OF THESE COULD PRODUCE LOCALIZED DOWNPOURS AS
PWATS LOOK TO RAMP TO NEARLY 2 INCHES. ANY OF THESE THUNDERSTORMS
COULD PRODUCE PONDING OF WATER ON ROADWAYS AND AREAS OF POOR
DRAINAGE.
EVEN SO...AVERAGE BASIN RAINFALL ON TUESDAY WILL LIKELY REMAIN AT OR
BELOW A QUARTER INCH. MAJOR RIVERS WILL LIKELY SEE ONLY MINOR RISES
IF THAT.
BY WEDNESDAY...AS COLD FRONT PLOWS INTO THE TROPICAL
AIR...THUNDERSTORMS COULD BE A BIT MORE NUMEROUS AND AGAIN CONTAIN
TORRENTIAL DOWNPOURS LEADING TO MINOR FLOODING.
BY THURSDAY...THIS FRONT LOOKS TO STALL JUST SOUTH OF OUR REGION. AT
THE SAME TIME...SOME SORT OF TROPICAL SYSTEM LOOKS TO SPIN UP ALONG
THE EASTERN SEABOARD TO OUR SOUTH. WHILE ALL MODELS HAVE THE ACTUAL
ENTITY MISSING OUR REGION...A PREDECESSOR RAINFALL EVENT (PRE) IS
FORECAST BY ALL MODELS TO FORM ALONG THIS BOUNDARY. THIS QUESTION IS
HOW FAR NORTH THIS PRE WILL GET WHICH COULD PRODUCE SIGNIFICANT
WIDESPREAD RAINFALL THURSDAY.
STAY TUNED.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...HWJIV
LONG TERM...BGM
AVIATION...BGM
FIRE WEATHER...HWJIV
HYDROLOGY...HWJIV
AREA FORECAST DISCUSSION
NWS NEW YORK NY
457 AM EDT MON JUN 30 2014
.SYNOPSIS...
THE REGION WILL BE IN BETWEEN THE BERMUDA HIGH AND A SLOWLY
APPROACHING COLD FRONT THROUGH WEDNESDAY NIGHT. THE FRONT WILL
MOVE SLOWLY ACROSS FROM THURSDAY INTO FRIDAY. POTENTIAL LOW
PRESSURE MOVING NORTH ALONG THE EAST COAST SHOULD PASS SOUTH OF
THE REGION FRIDAY INTO FRIDAY NIGHT. HIGH PRESSURE WILL THEN BUILD
IN FOR THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 330 AM...HIGH TO MID CLOUDS ARE DISSIPATING AS THEY SPREAD
EAST INTO WESTERN NJ AND WESTERN ORANGE COUNTY. PCPN OVER NE PA
HAS DISSIPATED.
BROKEN CLOUDS...MENTIONED ABOVE...PASS ACROSS THE REGION THIS
MORNING AND THEN THIN THIS AFTERNOON.
HAVE CONTINUED THE 20 TSTM POP FOR ORANGE COUNTY FOR LATE AFTN AS
A DISSIPATING STORM COULD MAKE IT INTO THAT PART OF THE
FORECAST AREA.
HIGH TEMPS WILL BE NEAR 80 FOR THE COASTAL REGION IN A REPEAT OF
SUNDAY`S SEA BREEZE PATTERN. AWAY FROM THE COAST...MID 80S
EXPECTED...THOUGH THIS DEPENDS SOMEWHAT ON THE AMOUNT OF
CLOUD COVER.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
DEW POINTS CONTINUE A SLOW INCREASE THROUGH THE PERIOD AS
SOUTHERLY FLOW GRADUALLY INCREASES.
HAVE REMOVED THE FOG FROM THE FORECAST FOR TONIGHT. THINKING IS
THAT WE MAY FORM MORE OF A LOW STRATUS CONDITION ALONG THE COAST.
THIS BASED ON LATEST RAP SOUNDINGS AND MOS GUIDANCE. WITH WATER
TEMPS AROUND 70...ADVECTION FOG DOES NOT SEEM LIKELY.
ON TUESDAY...TEMPS CONTINUE TO SLOWLY WARM AND HAVE GONE WITH THE
WARMER GFS MOS.
CONTINUED THE 20-30 POP TO THE NW OF NYC WITH SBCAPE IN THE NAM
NEARING 1000 J/KG.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
ACTIVE WEATHER POSSIBLE LATE IN THE WEEK.
EAST COAST RIDGE GIVES WAY TO APPROACHING TROUGH MID TO LATE WEEK.
SFC HIGH PRESSURE OVER THE ATLANTIC DEPARTS AS THE SLOW MOVING COLD
FRONT APPROACHES THE AREA.
WARM AND HUMID WEATHER IS EXPECTED...WITH MAINLY DIURNALLY DRIVEN
SHOWERS AND THUNDERSTORMS THROUGH WEDNESDAY...WITH HIGHEST POPS
ACROSS THE INTERIOR. THEN POPS INCREASE THURSDAY...THURSDAY NIGHT
AND FRIDAY AS THE FRONT NEARS. PLENTY OF MOISTURE WILL BE TAPPED AS
TROPICAL LOW OFF THE SOUTHEAST COAST LOOKS TO GET PICKED UP BY
SOUTHERLY STEERING WINDS AHEAD OF THE TROUGH.
ECMWF...GFS SEEM TO BE IN REASONABLE AGREEMENT ON THE TRACK OF THE
FRONT...AND TROPICAL LOW. HEAVY RAIN IS POSSIBLE LATER
THURSDAY...THURSDAY NIGHT AND POSSIBLY INTO FRIDAY.
THE TROUGH MOVES ACROSS THE NORTHEAST WITH A RIDGE BUILDING IN
BEHIND FOR A GOOD PORTION OF THE WEEKEND.
WARM TEMPS ARE EXPECTED AS PERSISTENT SOUTHERLY FLOW PREVAILS. ABOVE
NORMAL READINGS CAN BE EXPECTED TUESDAY NIGHT THROUGH WEDNESDAY
NIGHT...WITH CLOSER TO NORMAL READINGS THEREAFTER. HOTTEST DAY THIS
TIME FRAME APPEARS TO BE WEDNESDAY WITH READINGS IN THE 80S TO
AROUND 90.
INCREASING CLOUDS AND HIGHER COVERAGE OF SHOWERS/TSTMS THURSDAY AND
FRIDAY WILL KNOCK A FEW DEGREES OFF DAYTIME TEMPS. PLENTY OF
SUNSHINE OVER THE WEEKEND SHOULD RESULT IN NEAR NORMAL READINGS BEHIND
THE LOW/FRONT.
&&
.AVIATION /09Z MONDAY THROUGH FRIDAY/...
HIGH PRESSURE OFF THE MID ATLANTIC COAST WILL DRIFT SLOWLY
EASTWARD...WITH CONTINUED S-SW FLOW.
VFR EXCEPT AT KGON...WHERE LOW STRATUS THAT DEVELOPED OVER
INTERIOR SE CT SHOULD SPREAD DOWN TOWARD THE COAST. CANNOT TOTALLY
RULE OUT EXPANSION TO KBDR OR KISP...AND WILL HAVE TO WATCH THIS
CAREFULLY INTO THE EARLY DAYLIGHT HOURS.
AFTERNOON SEA BREEZES WILL INCREASE WINDS TO 10 TO 15 KT AT THE
COASTAL TERMINALS. GUSTS UP TO 20 KT ARE POSSIBLE FROM LATE DAY
INTO EARLY EVENING AT KJFK/KLGA/KISP. WINDS DIMINISH THEREAFTER.
...NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS
CAN BE FOUND AT: HTTP://WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.
KLGA FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.
KEWR FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH
IMPLIES SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.
KHPN FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.
KISP FCSTER COMMENTS: BRIEF IFR CIGS POSSIBLE BEFORE 13Z.
.OUTLOOK FOR 06Z TUE THROUGH FRI...
.LATE MON NIGHT...PATCHY LOW CLOUDS WITH MVFR OR IFR CONDS ARE
LIKELY AT KGON...AND POSSIBLE AT THE OTHER TERMINALS LATE.
.TUE...CHANCE OF AN AFTERNOON TSTM WITH BRIEF MVFR OR LOWER CONDS
AND/OR AND GUSTY WINDS AT KSWF. FOG AND LOW STRATUS WITH MVFR OR
LOWER CONDS LIKELY LATE AT NIGHT.
.WED...FOG AND LOW STRATUS WITH MVFR OR LOWER CONDS BURNING OFF
EARLY IN THE MORNING. CHANCE OF SHOWERS/TSTMS WITH MVFR OR LOWER
CONDS IN THE AFTERNOON MAINLY FROM NYC METRO NORTH AND
WEST...SPREADING TO THE COAST IN THE EVENING.
.THU-FRI...NUMEROUS SHOWERS/TSTMS...WITH IFR CONDS IN HEAVY
RAIN POSSIBLE.
&&
.MARINE...
SEA BREEZES AGAIN LATE THIS AFTN WILL RESULT IN A PERIOD OF 15 KT
WITH GUST UP TO 20 KT ON THE WATERS. HIGHEST WOULD BE IN SOUTH OF
THE ROCKAWAYS.
SEA BREEZES ARE STRONGER YET TUESDAY AFTN WITH GUSTS UP TO 25 KT
AND THE POTENTIAL FOR SCA CONDITIONS...ESPECIALLY ON THE OCEAN.
PERSISTENT SOUTHERLY FLOW TUESDAY NIGHT WILL DIMINISH WEDNESDAY AND
THURSDAY AS A COLD FRONT APPROACHES AND THE PRESSURE GRADIENT
WEAKENS. WITH THE FRONT SLOWLY MOVING ACROSS THE WATERS EARLY
FRIDAY...WINDS REMAIN RATHER LIGHT. NEED TO MONITOR EVENTUAL
PROGRESSION OF A TROPICAL LOW LATE FRIDAY AS IT POSSIBLY APPROACHES
THE WATERS FROM THE SOUTH.
OCEAN SEAS OF 3 TO 6 FEET TUESDAY NIGHT WILL SUBSIDE AS THE
SOUTHERLY WINDS DIMINISH WEDNESDAY THROUGH THURSDAY. AT THIS
TIME...SEAS SHOULD REMAIN BELOW 5 FT MOST OF FRIDAY...BUT WOULD
LIKELY BUILD LATE IN THE DAY DEPENDING ON TRACK AND STRENGTH OF LOW
PRESSURE TO THE SOUTH.
&&
.HYDROLOGY...
NO SIGNIFICANT PRECIPITATION IS EXPECTED INTO TUESDAY.
THERE IS THE POTENTIAL FOR SIGNIFICANT RAINFALL TOWARD THE END OF
THE WEEK...THURSDAY AND THURSDAY NIGHT. AT THIS TIME THERE IS TOO
MUCH UNCERTAINTY TO SPECIFY EXACT AMOUNTS OR SPECIFIC THREATS.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TONGUE/PW
NEAR TERM...TONGUE
SHORT TERM...TONGUE
LONG TERM...PW
AVIATION...GOODMAN
MARINE...TONGUE/PW
HYDROLOGY...TONGUE/PW
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
359 AM EDT MON JUN 30 2014
.SYNOPSIS...
THE REGION WILL BE IN BETWEEN THE BERMUDA HIGH AND A SLOWLY
APPROACHING COLD FRONT THROUGH WEDNESDAY NIGHT. THE FRONT WILL
MOVE SLOWLY ACROSS FROM THURSDAY INTO FRIDAY. POTENTIAL LOW
PRESSURE MOVING NORTH ALONG THE EAST COAST SHOULD PASS SOUTH OF
THE REGION FRIDAY INTO FRIDAY NIGHT. HIGH PRESSURE WILL THEN BUILD
IN FOR THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 330 AM...HIGH TO MID CLOUDS ARE DISSIPATING AS THEY SPREAD
EAST INTO WESTERN NJ AND WESTERN ORANGE COUNTY. PCPN OVER NE PA
HAS DISSIPATED.
BROKEN CLOUDS...MENTIONED ABOVE...PASS ACROSS THE REGION THIS
MORNING AND THEN THIN THIS AFTERNOON.
HAVE CONTINUED THE 20 POP TSTM FOR ORANGE COUNTY FOR LATE AFTN AS
A DISSIPATING STORM COULD MAKE IT INTO THAT PART OF FORECAST AREA.
TEMPS ARE NEAR 80 FOR THE COASTAL REGION IS A REPEAT OF SUNDAY`S
SEA BREEZE PATTERN IS IN STORE FOR THE REGION. AWAY FROM THE
COAST...MID 80S EXPECTED...THOUGH THIS DEPENDS SOMEWHAT ON THE
AMOUNT OF CLOUD COVER.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
DEW POINTS CONTINUE A SLOW INCREASE THROUGH THE PERIOD AS
SOUTHERLY FLOW GRADUALLY INCREASES.
HAVE REMOVED THE FOG FROM THE FORECAST FOR TONIGHT. THINKING IS
THAT WE MAY FORM MORE OF A STRATUS CONDITION ALONG THE COAST. THIS
BASED ON LATEST RAP SOUNDINGS AND MOS GUIDANCE. WITH WATER TEMPS
AROUND 70...ADVECTION FOG DOES NOT SEEM LIKELY.
ON TUESDAY...TEMPS CONTINUE TO SLOWLY WARM AND HAVE GONE WITH THE
WARMER GFS MOS.
CONTINUED THE 20-30 POP TO THE NW OF NYC WITH SBCAPE`S IN THE NAM
NEARING 1000 J/KG.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
ACTIVE WEATHER POSSIBLE LATE IN THE WEEK.
EAST COAST RIDGE GIVES WAY TO APPROACHING TROUGH MID TO LATE WEEK.
SFC HIGH PRESSURE OVER THE ATLANTIC DEPARTS AS THE SLOW MOVING COLD
FRONT APPROACHES THE AREA.
WARM AND HUMID WEATHER IS EXPECTED...WITH MAINLY DIURNALLY DRIVEN
SHOWERS AND THUNDERSTORMS THROUGH WEDNESDAY...WITH HIGHEST POPS
ACROSS THE INTERIOR. THEN POPS INCREASE THURSDAY...THURSDAY NIGHT
AND FRIDAY AS THE FRONT NEARS. PLENTY OF MOISTURE WILL BE TAPPED AS
TROPICAL LOW OFF THE SOUTHEAST COAST LOOKS TO GET PICKED UP BY
SOUTHERLY STEERING WINDS AHEAD OF THE TROUGH.
ECMWF...GFS SEEM TO BE IN REASONABLE AGREEMENT ON THE TRACK OF THE
FRONT...AND TROPICAL LOW. HEAVY RAIN IS POSSIBLE LATER
THURSDAY...THURSDAY NIGHT AND POSSIBLY INTO FRIDAY.
THE TROUGH MOVES ACROSS THE NORTHEAST WITH A RIDGE BUILDING IN
BEHIND FOR A GOOD PORTION OF THE WEEKEND.
WARM TEMPS ARE EXPECTED AS PERSISTENT SOUTHERLY FLOW PREVAILS. ABOVE
NORMAL READINGS CAN BE EXPECTED TUESDAY NIGHT THROUGH WEDNESDAY
NIGHT...WITH CLOSER TO NORMAL READINGS THEREAFTER. HOTTEST DAY THIS
TIME FRAME APPEARS TO BE WEDNESDAY WITH READINGS IN THE 80S TO
AROUND 90.
INCREASING CLOUDS AND HIGHER COVERAGE OF SHOWERS/TSTMS THURSDAY AND
FRIDAY WILL KNOCK A FEW DEGREES OFF DAYTIME TEMPS. PLENTY OF
SUNSHINE OVER THE WEEKEND SHOULD RESULT IN NEAR NORMAL READINGS BEHIND
THE LOW/FRONT.
&&
.AVIATION /07Z MONDAY THROUGH FRIDAY/...
HIGH PRESSURE OFF THE MID ATLANTIC COAST WILL DRIFT SLOWLY
EASTWARD...WITH CONTINUED S-SW FLOW.
VFR EXCEPT AT KGON...WHICH SHOULD SEE MVFR VSBY DEVELOP LATE WITH
OCNL IFR VSBY.
AFTERNOON SEA BREEZES WILL INCREASE WINDS TO 10 TO 15 KT AT THE
COASTAL COASTAL TERMINALS. GUSTS UP TO 20 KT ARE POSSIBLE FROM
LATE DAY INTO EARLY EVENING AT KJFK/KLGA/KISP. WINDS DIMINISH
THEREAFTER.
.OUTLOOK FOR 06Z TUE THROUGH FRI...
.LATE MON NIGHT...PATCHY LOW CLOUDS/FOG LIKELY AT KGON...AND
POSSIBLE AT THE OTHER TERMINALS LATE.
.TUE-WED...MAINLY AFTERNOON/EVENING TSTM DEVELOPMENT POSSIBLE...
ESPECIALLY FROM NYC METRO AND KBDR NORTH/WEST.
.THU-FRI...SCT SHOWERS/TSTMS POSSIBLE.
&&
.MARINE...
SEA BREEZES AGAIN LATE THIS AFTN WILL RESULT IN A PERIOD OF 15 KT
WITH GUST UP TO 20 KT ON THE WATERS. HIGHEST WOULD BE IN SOUTH OF
THE ROCKAWAYS.
SEA BREEZES ARE STRONGER YET TUESDAY AFTN WITH GUSTS UP TO 25 KT
AND THE POTENTIAL FOR SCA CONDITIONS...ESPECIALLY ON THE OCEAN.
PERSISTENT SOUTHERLY FLOW TUESDAY NIGHT WILL DIMINISH WEDNESDAY AND
THURSDAY AS A COLD FRONT APPROACHES AND THE PRESSURE GRADIENT
WEAKENS. WITH THE FRONT SLOWLY MOVING ACROSS THE WATERS EARLY
FRIDAY...WINDS REMAIN RATHER LIGHT. NEED TO MONITOR EVENTUAL
PROGRESSION OF A TROPICAL LOW LATE FRIDAY AS IT POSSIBLY APPROACHES
THE WATERS FROM THE SOUTH.
OCEAN SEAS OF 3 TO 6 FEET TUESDAY NIGHT WILL SUBSIDE AS THE
SOUTHERLY WINDS DIMINISH WEDNESDAY THROUGH THURSDAY. AT THIS
TIME...SEAS SHOULD REMAIN BELOW 5 FT MOST OF FRIDAY...BUT WOULD
LIKELY BUILD LATE IN THE DAY DEPENDING ON TRACK AND STRENGTH OF LOW
PRESSURE TO THE SOUTH.
&&
.HYDROLOGY...
NO SIGNIFICANT PRECIPITATION IS EXPECTED INTO TUESDAY.
THERE IS THE POTENTIAL FOR SIGNIFICANT RAINFALL TOWARD THE END OF
THE WEEK...THURSDAY AND THURSDAY NIGHT. AT THIS TIME THERE IS TOO
MUCH UNCERTAINTY TO SPECIFY EXACT AMOUNTS OR SPECIFIC THREATS.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TONGUE/PW
NEAR TERM...TONGUE
SHORT TERM...TONGUE
LONG TERM...PW
AVIATION...GOODMAN
MARINE...TONGUE/PW
HYDROLOGY...TONGUE/PW
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
502 AM EDT MON JUN 30 2014
...LOW PRESSURE BEING MONITORED FOR TROPICAL DEVELOPMENT AS IT
DRIFTS TOWARDS THE EAST CENTRAL FLORIDA COAST...
.CURRENTLY...
EARLY MORNING SURFACE ANALYSIS DEPICTS LOW PRESSURE (1014
MILLIBARS) CENTERED ABOUT 210 MILES TO THE EAST-SOUTHEAST OF ST.
AUGUSTINE. THIS SYSTEM REMAINS DISORGANIZED...WITH ALL OF THE
CONVECTION DISPLACED TO THE SOUTH AND EAST OF THIS LARGE
CIRCULATION...OR OVER THE BAHAMAS AND THE GULF STREAM WATERS
ADJACENT TO EAST CENTRAL FLORIDA. THE WESTERN PERIPHERY OF THIS
CONVECTION IS LOCATED BEYOND 50 NAUTICAL MILES EAST OF THE FLAGLER
COUNTY COASTLINE. MEANWHILE...HIGH PRESSURE (1020 MILLIBARS) HAS
RETROGRADED WESTWARD DURING THE PAST 24 HOURS...AND IS NOW
CENTERED SOUTH OF THE FLORIDA PANHANDLE COAST. ALOFT...DEEP-
LAYERED RIDGING COVERS THE GULF OF MEXICO AND MOST OF THE
SOUTHEASTERN U.S...WHILE ATLANTIC RIDGING NOSES WESTWARD TOWARDS
THE SOUTHEASTERN BAHAMAS. CONVECTION THAT BLOSSOMED DURING THE
LATE EVENING HOURS OVER SOUTH CENTRAL GEORGIA WANED QUICKLY AFTER
CROSSING THE ALTAMAHA RIVER. FAIR SKIES WERE OBSERVED THROUGHOUT
OUR LAND AREAS...WITH TEMPERATURES AT 09Z RANGING FROM THE LOW/MID
70S INLAND TO NEAR 80 AT THE COAST.
.NEAR TERM (TODAY AND TONIGHT)...
MOST OF OUR REGION WILL REMAIN ON THE SUBSIDENT WESTERN PERIPHERY
OF THE LARGE CYCLONIC CIRCULATION OFFSHORE. MODEL SOUNDINGS
DEPICT DRIER AIR ADVECTING INTO COASTAL SOUTHEAST GA AND NORTHEAST
FL AS THE DAY PROGRESSES...WITH PRECIPITABLE WATER VAPOR (PWAT)
VALUES FALLING TO NEAR 1.5 INCHES THIS AFTERNOON...WHICH SHOULD
LIMIT CONVECTIVE DEVELOPMENT ALONG MOST OF THE INTERSTATE 95
CORRIDOR TODAY. THE HIGH-RES HRRR MODEL DEPICTS A FEW SHOWERS
IMPACTING FLAGLER AND ST. JOHNS COUNTIES DURING THE LATE MORNING
AND EARLY AFTERNOON HOURS...AND INCLUDED ISOLATED TO WIDELY
SCATTERED POPS IN THE FORECAST GRIDS FOR THESE LOCATIONS. DEEPER
MOISTURE WILL BE LOCATED IN A RIBBON FROM INTERIOR SOUTHEAST GA TO
THE FL BIG BEND...AND WIDELY SCATTERED CONVECTION SHOULD FIRE IN
THESE AREAS DURING THE AFTERNOON HOURS...WITH HIGHER CHANCES WEST
OF INTERSTATE 75...WHERE THE GULF COAST SEA BREEZE WILL
POTENTIALLY ENHANCE ACTIVITY. A FEW WET MICROBURSTS WILL BE
POSSIBLE WITHIN STRONGER ACTIVITY THAT DEVELOPS AS DRIER AIR ALOFT
POTENTIALLY ENHANCES DOWNDRAFTS. STORM MOTION IS EXPECTED TO BE
TOWARDS THE SOUTHWEST AT 10-15 MPH.
OUR LOCAL PRESSURE GRADIENT WILL CONTINUE TO SLOWLY TIGHTEN...WITH
BREEZY NE WINDS EXPECTED ALONG THE NORTHEAST FL COAST BY THIS
AFTERNOON. ONSHORE WINDS WILL KEEP HIGHS IN THE UPPER 80S AT THE
COAST...BUT SEASONABLY HOT CONDITIONS WILL PREVAIL INLAND...WITH
HIGHS IN INTERIOR SOUTHEAST GA AND THE SUWANNEE VALLEY REACHING
THE MID 90S BEFORE CONVECTION DEVELOPS LATER THIS AFTERNOON. THE
TREND OF DRY AIR MIXING TO THE SURFACE SHOULD CONTINUE IN THESE
LOCATIONS...WITH AFTERNOON DEW POINTS IN THE 60S...KEEPING HEAT
INDICES BELOW 105 DEGREES. EVENING CONVECTION ALONG AND WEST OF
THE I-75 CORRIDOR WILL WANE AS THE EVENING PROGRESSES...WITH A FEW
COASTAL SHOWERS REMAINING POSSIBLE SOUTH OF ST. AUGUSTINE AS LOW
PRESSURE EDGES TOWARDS THE EAST CENTRAL FL COAST OVERNIGHT. LOWS
TONIGHT WILL RANGE FROM THE LOW/MID 70S INLAND TO NEAR 80 AT THE
COAST.
.SHORT TERM (TUESDAY THROUGH WEDNESDAY NIGHT)...
SYNOPSIS...THE 00Z MODELS HAVE COME INTO BETTER AGREEMENT WITH AT
LEAST THE DIRECTIONAL WIND FIELD WITH THE LOW OFFSHORE...BUT THERE
REMAINS DISAGREEMENT BETWEEN THE WEAKER GFS AND THE STRONGER
NAM12/ECMWF. THE MODEL SUITE DRIFTS THE LOW FROM OFFSHORE OF THE
SE FL ATLANTIC COAST TUE NNW ALONG THE FL COASTLINE THROUGH TUE
NIGHT. BY WED MORNING THE SFC LOW IS PROGGED TO BE NEAR THE
N-CENTRAL FL ATLANTIC COAST AND THEREAFTER THERE IS MODEL
DISCREPANCIES AS THE GFS ADVERTISED THE LOW BECOME BROAD AND DRIFT
IT INLAND OVER THE AREA INTO A SURFACE TROUGH DRAPED ACROSS GA.
THE ECMWF/NAM12 SOLUTIONS ADVERTISED THE CLOSED LOW REMAINING
OFFSHORE PARALLELING THE N-FL/GA COAST TOWARD SC THROUGH WED NIGHT
UNTIL IT GETS PICKED UP BY THE MID LEVEL TROUGH CARVING OUT ALONG
THE EASTERN SEABOARD. FOR THIS PACKAGE INCREASED RAIN CHANCES
ALONG THE IMMEDIATE COAST AND ADJACENT MARINE WATERS TUE THROUGH
WED NIGHT AND USED A BLEND OF THE MODELS WIND FIELD BUT CAPPED
WINDS AT 20 KTS OFFSHORE.
TUE & TUE NIGHT...THE DRY SLOT WILL CONTINUE TO LIMIT CONVECTIVE
DEVELOPMENT...AND ADVERTISED A LOW 20% CHANCE OF COASTAL SHOWERS
TO START THE DAY UNDER INCREASINGLY BREEZY NNE FLOW ALONG THE
COAST WITH SPEEDS 15-20 MPH. BY MIDDAY ADVERTISED 30-40% CHANCES
OF POSSIBLE FRINGE SQUALLS BRUSHING ALONG THE COAST GENERALLY
SOUTH OF ST AUGUSTINE...WITH INLAND RAIN CHANCES WEST OF THE ST
JOHNS BASIN AND OVER SE GA ONLY IN THE 25-30%...WITH HIGH 35-40%
CHANCES WEST OF THE I-75 CORRIDOR TUE EVENING WHERE STRONGEST SEA
BREEZE/OUTFLOW CONVERGENCE WILL OCCUR. TUE NIGHT PRECIP DWINDLES
INLAND WHILE THE COAST COULD BE SKIRTED BY PASSING SQUALLS THE LOW
TRACKS NORTHWARD ALONG THE N-CENTRAL FL ATLANTIC COAST. ADVERTISED
RAIN CHANCES OF 40-50% GENERALLY W OF THE INTERSTATE 95 TO 20%
OVER INLAND NE FL TUE NIGHT WITH LESS THAN 10% RAIN CHANCES OVER
INLAND SE GA. TEMPS WILL BE WARM TUE WITH HIGH AGAIN IN THE MID
90S OVER INLAND SE GA AND THE I-10 CORRIDOR OF THE SUWANNEE RIVER
VALLEY..WITH LOW 90S ELSEWHERE INLAND. THE NNE FLOW AND INCREASING
CLOUDS WILL KEEP THE COAST IN THE UPPER 80S. MINS TUE NIGHT WILL
BE MILD UNDER BREEZY NNW WINDS ALONG THE COAST WITH LOWS IN THE
MID/UPPER 70S RIVER/COAST TO LOWER 70S FARTHER INLAND.
WED & WED NIGHT...INCREASED RAIN CHANCES ALONG THE COAST TO 60% AS
THE LOW IS EXPECTED TO TRACK NWD OFFSHORE DURING THIS PERIOD WITH
WEST SIDE SQUALLS POTENTIALLY IMPACTING OUR COASTAL AREAS. CAPPED
WINDS ALONG THE COAST TO 15-20 MPH FOR NOW WITH GUSTS UP TO 25-30
MPH POSSIBLE. FARTHER INLAND CONVECTION WILL BE ENHANCED BY
DAYTIME HEATING WITH CONVERGENCE FOCUSED ALONG A TROUGH AXIS
EXTENDING WEST OF THE SFC LOW FROM INLAND NE FL AND WESTWARD
ACROSS THE FL PANHANDLE. CAPPED RAIN CHANCES TO 30-40% FOR AREAS
WEST OF THE I-95 CORRIDOR WED AFTN. TEMPS WILL AGAIN RISE INTO THE
MID 90S WELL INLAND OVER SE GA WITH INCREASE CLOUD COVER KEEPING
FL AND THE IMMEDIATE COAST SLIGHTLY COOLER WITH HIGHS NEAR 90
INLAND MID/UPPER 80S COAST. WED NIGHT THE LOW IS EXPECTED TO
CONTINUE TO TRACK NORTH OF THE LOCAL AREA BEFORE IT IS PICKED UP
BY A DEEPENING EASTERN CONUS TROUGH. ADVERTISE OUR PRECIP CHANCES
FADING WITH LOSS OF HEATING INLAND AND KEPT 30-40% CHANCES ALONG
THE COAST AND THE EASTERN HALF OF SE GA AS THE LOW PULLS AWAY AND
A WAKE TROUGH AXIS LINGERS OVER THE LOCAL AREA.
AGAIN...THIS FORECAST IS HIGHLY DEPENDENT ON THE
TRACK/INTENSITY/STRUCTURE OF THE LOW DEVELOPING OFFSHORE OF THE FL
ATLANTIC COAST...SO PLEASE CONTINUE TO MONITOR THIS LOWS EVOLUTION
OVER THE NEXT SEVERAL DAYS AND ITS POTENTIAL LOCAL IMPACTS.
.LONG TERM (THURSDAY THROUGH MONDAY)...
LOW PRESSURE IS EXPECTED TO TRACK NE ALONG THE SE ATLANTIC
SEABOARD THU WITH A TRAILING WAKE TROUGH EXTENDING ACROSS THE
LOCAL FORECAST AREA. INCREASED RAIN CHANCES INTO THE 40-50% RANGE
WITH A DOMINANT WEST COAST SEA BREEZE REGIME. WSW STEERING FLOW
WILL CONTINUE FRI WITH THE LINGERING TROUGH AXIS MEANDERING ACROSS
THE REGION...BUT MODELS DIVERGE ON THE MOISTURE FIELDS WITH THE
ECMWF BRINGING IN A SWATH OF DRIER AIR AS THE LOW DEEPENS OFFSHORE
OF THE MID-ATLANTIC COAST WHILE THE GFS KEEPS MOISTURE RELATIVELY
HIGH LOCALLY AND THE LOW NOT AS STRONG TO THE NE OF THE REGION.
OPTED TO LEAN TOWARD CLIMO RAIN CHANCES NEAR 40% UNDER A
PREVAILING WESTERLY STEERING FLOW AND SLIGHTLY HIGHER RAIN CHANCES
OVER SE GA COMPARED TO NE FL AS THE BERMUDA RIDGE AXIS RE-
ESTABLISHES OVER THE SOUTHERN FL PENINSULA. NEXT WEEKEND CONTINUED
WITH 30-40% RAIN CHANCES UNDER PREVAILING WSW FLOW...THEN MON
ADVERTISED THE HIGHER CORE OF RAIN CHANCES INLAND BETWEEN I-75 AND
THE ST JOHNS RIVER BASIN AS THE MEAN RIDGE AXIS LIFTS FARTHER
NORTHWARD UP THE FL PENINSULA WITH SOUTHERLY STEERING FLOW IN
PLACE. TEMPS WILL BE NEAR TO SLIGHTLY ABOVE CLIMO VALUES WITH HIGH
TEMPS IN THE LOW/MID 90S INLAND TO UPPER 80S COAST AND MINS IN THE
LOW/MID 70S.
&&
.AVIATION...
MVFR/BRIEF PERIODS OF MVFR CONDITIONS ARE EXPECTED AT VQQ THROUGH
12Z. OTHERWISE...VFR CONDITIONS WILL PREVAIL AT THE REGIONAL
TERMINALS THROUGH AT LEAST 20Z. WIDELY SCATTERED THUNDERSTORMS MAY
IMPACT GNV TOWARDS 20Z. TIMING AND INTENSITY REMAIN IN
QUESTION...AND INCLUDED VCTS AT GNV THROUGH 00Z IN THE LATEST TAF
ISSUANCE. NORTHEAST SURFACE WINDS WILL INCREASE TO 10-15 KNOTS
TOWARDS 15Z AT THE REGIONAL TERMINALS...WITH GUSTS UP TO 20 KNOTS
POSSIBLE AT CRG AND SSI THROUGH 00Z.
&&
.MARINE...
SMALL CRAFT SHOULD EXERCISE CAUTION IN BOTH THE NEAR SHORE AND
OFFSHORE WATERS TODAY AS LOW PRESSURE CENTERED ABOUT 210 MILES
EAST-SOUTHEAST OF ST. AUGUSTINE THIS MORNING DRIFTS SOUTHWARD.
THIS SYSTEM IS EXPECTED TO BECOME BETTER ORGANIZED AS IT DRIFTS
SOUTH-SOUTHWESTWARD INTO THE WATERS ADJACENT TO EAST CENTRAL
FLORIDA TONIGHT AND TUES. THIS LOW PRESSURE CENTER IS THEN
EXPECTED TO TURN NORTHWARD...LIKELY MOVING THROUGH THE OFFSHORE
WATERS ADJACENT TO NORTHEAST FL ON WED...AND INTO THE OFFSHORE GA
WATERS BY WED NIGHT BEFORE ACCELERATING NORTHEASTWARD AND AWAY
FROM OUR REGION ON THURSDAY. SMALL CRAFT ADVISORY CONDITIONS ARE
POSSIBLE ON TUES/WED DEPENDING ON TRACK AND INTENSITY OF THIS
SYSTEM...WITH SQUALLS ON THE WESTERN PORTION OF THE CIRCULATION
POSSIBLY IMPACTING OUR COASTAL WATERS. DUE TO UNCERTAINTY OF THE
FUTURE TRACK AND INTENSITY...CAUTION CRITERIA WINDS/SEAS WERE
MAINTAINED IN THE OFFSHORE WATERS THROUGH THURSDAY NIGHT. WINDS
AND SEAS WILL SUBSIDE BY FRIDAY AS THIS SYSTEM MOVES AWAY FROM OUR
REGION.
RIP CURRENTS: MODERATE RISK EXPECTED THROUGH AT LEAST WEDNESDAY AS
ONSHORE WINDS CONTINUE AND EASTERLY SWELLS BUILD.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 96 72 96 73 / 40 30 30 30
SSI 87 77 88 76 / 10 10 30 30
JAX 91 74 92 74 / 10 10 30 30
SGJ 87 76 88 75 / 20 20 40 40
GNV 94 72 91 72 / 20 20 30 30
OCF 93 72 92 72 / 40 30 40 40
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
NELSON/ENYEDI
AREA FORECAST DISCUSSION...UPDATED
NWS CHICAGO/ROMEOVILLE IL
230 AM CDT MON JUN 30 2014
.MESOSCALE DISCUSSION...
229 AM CDT...
THE SUPERCELLULAR STORM WHICH PROMPTED A TORNADO WARNING FOR MCHENRY
COUNTY HAS SHOWN A WEAKENING TREND WITH REGARD TO ROTATION SINCE
ABOUT 210 AM CDT ON THE LOT...MKX...AND TDWRS WITHIN VIEWING RANGE.
THE STORM HAS BECOME MORE OUTFLOW OR REAR FLANK DOWNDRAFT-DRIVEN. IN
ADDITION...NO FURTHER FUNNEL CLOUD REPORTS OR ANY INDICATION OF A
TORNADO/WIND DAMAGE THUS FAR HAVE BEEN RECEIVED. THUS A NEW TORNADO
WARNING HAS NOT BEEN ISSUED INTO LAKE COUNTY. WILL CONTINUE TO
WATCH THIS STORM VERY CLOSELY.
OVERALL STORMS ACROSS NORTHERN ILLINOIS HAVE SHOWN A GENERAL
WEAKENING TREND AS THEY HAVE HEADED EAST...PARTICULARLY THE BOOKEND
VORTEX AND BOWING STRUCTURE NEAR AND JUST SOUTH OF INTERSTATE 88.
AMDAR DATA DOES INDICATE A LITTLE STRONGER INVERSION IN PLACE ACROSS
CHICAGOLAND AND WOULD EXPECT SEVERE THREAT TO BE LIMITED EAST OF
CURRENT WATCH...AS WELL AS GRADUALLY DIMINISHING IN THE CURRENT
WATCH RAIN HAVING DROPPED THE SURFACE TEMPERATURES 5-10 DEGREES
LIMITING MUCH FOR WIND/TORNADO POTENTIAL.
MTF
//PREV DISCUSSION... 204 PM CDT
TONIGHT...
LINGERING STRATUS CLOUDS FINALLY BURNED OFF LATE THIS MORNING...WITH
SOME SCATTERED CUMULUS DEVELOPING EARLY THIS AFTN. VISIBLE IMAGERY
INDICATES SOME OF THE CU FIELD WAS BECOMING AGITATED AND TRYING TO
BUILD SOUTH OF I-80 THIS AFTN...WHICH WAS THE REGION WHERE BETTER
MOISTURE WAS AVAILABLE AS DEW POINTS LINGERED ARND 70 TO LOW 70S.
THE STRONGER WAVE WAS STILL WELL WEST OF THE CWFA INTO
CENTRAL/WESTERN IOWA...WITH THE FOCUS FOR STRONG/SEVERE STORMS THIS
AFTN/EVE WILL RESIDE. FURTHER EAST ACROSS NORTHERN IL/NORTHWEST
IN...THE ATMOSPHERE WILL STEADILY BECOME MORE UNSTABLE. SOUNDINGS
CONTINUE TO INDICATE A WEAK WARM LAYER ALOFT...HOWEVER IT HAS BEEN
SLIGHTLY COOLER THAN WAS EXPECTED. WHICH WILL LIKELY KEEP TEMPS
SLIGHTLY COOLER THIS AFTN...ALTHOUGH A FEW POINTS ALONG AND SOUTH OF
LASALLE TO VALPARAISO COULD STILL TAG 90 THIS AFTN. OTHERWISE TEMPS
SHUD TOP OUT IN THE MID TO PERHAPS UPR 80S.
THE STORY FOR TONIGHT WILL BE SHOW OR NO-SHOW IN REGARDS TO
CONVECTION. THEN IN WHAT CAPACITY WILL IT ARRIVE ACROSS A PORTION OF
OUR CWFA TONIGHT/EARLY MON. LATEST RAP SOUNDINGS WOULD SUGGEST WE
ARE SITTING ON ABOUT 2K J/KG OF CAPE...UNFORTUNATELY A WARM LAYER
ALOFT WILL LIKELY KEEP CONVECTIVE COVERAGE TO A MINIMA THRU AT LEAST
23Z. UPSTREAM THE SPC MESOANALYSIS INDICATES THE INHIBITION OVER
CENTRAL IA SHUD BEGIN TO DISSOLVE BY 20-21Z...AND EXPECT AN UPTICK
IN CONVECTIVE GROWTH THERE. LOCAL ARW8KM SOLUTION HAS A SIMILAR WARM
LAYER ALOFT...WHICH WILL LIKELY ACT AS A CAP AND COULD LINGER TO
ARND 00Z MON TO POSSIBLY 04Z.
UTILIZING THE BUNKER STORM MOTION...IT APPEARS THAT IF CONVECTION
CAN DEVELOP UPSTREAM IT WOULD SLIDE EAST TOWARDS THE CENTRAL CWFA
THEN TURN SOUTHEAST CLIPPING THE SOUTHERN CWFA. BUT THE QUESTION
REMAINS WILL CONVECTION BE ABLE TO MAINTAIN ITSELF INTO THE CWFA
TONIGHT...AND WITH THE STRENGTHENING PUSH OF WARM AIR ALOFT THIS
LOOKS TO BE CHALLENGING.
EXPECT TEMPS TO REMAIN MILD WITH LOWS IN THE LOW 70S.
MONDAY...
THIS CONTINUES TO BE THE DAY OF GREATEST CONCERN FOR STRONG/SEVERE
STORMS. THE TIMING FOR CONVECTIVE DEVELOPMENT LOOKS TO BE FOCUSED IN
THE AFTN/EVE TIMEFRAME. THE DAY SHUD START OFF WITH SOME SCT SHOWERS
POSSIBLY AN ISOLATED STORM OR TWO. PROFILES INDICATE STEEPENING
LAPSE RATES BY EARLY AFTN...HOWEVER THERE IS STILL A SIZABLE PUSH
OF WARM AIR ALOFT THAT COULD KEEP THINGS CAPPED YET AGAIN THRU
21-22Z MON. GUIDANCE CONTINUES TO SUGGEST THE WAVE OVER IOWA ALONG
THE LEADING EDGE OF A MID-LVL TROUGH/VORT TO BE THE FOCAL POINT.
THIS FEATURE IS PROGGED TO ARRIVE OVER THE FORECAST AREA AFT
21Z...SO THE TIMING OF LATE AFTN/EVE FOR GREATEST CONVECTIVE GROWTH
AND COVERAGE REMAINS IN PLACE. STORM MOTION MON EVE LOOKS TO BE
PUSHING EAST THEN BEGIN TURNING SOUTHEAST. AT THIS TIME SPC HAS THE
ENTIRE AREA OUTLOOKED FOR SLIGHT RISK...WITH THE GREATEST HAZARDS
BEING LARGE HAIL AND DAMAGING WINDS.
TEMPS MON WILL HINGE UPON THE MORNING CLOUD COVERAGE AND HOW QUICKLY
THAT CAN ERODE. AT THIS TIME IT APPEARS TEMPS SHUD PUSH INTO THE
MID/UPR 80S WITH DEW PTS IN THE LOW 70S. THE COMBINATION WILL CREATE
HEAT INDEX VALUES IN THE MID/UPR 90S.
TUESDAY THROUGH THURSDAY...
DRY SLOT QUICKLY ARRIVES BEHIND THE VORT PASSAGE TUE...WHICH SHUD
ALLOW MUCH OF TUE TO BE DRY. LLVL FLOW WILL REMAIN SOUTHWESTERLY
WITH A MORE ROBUST MID-LVL TROUGH JUST UPSTREAM ACROSS THE NORTHERN
PLAINS THAT WILL ARRIVE ACROSS THE REGION WED. ANOTHER LOBE OF
VORTICITY IS PROGGED TO PIVOT OVERHEAD WED MORNING...AND WILL BRING
ANOTHER CHC FOR PRECIP. GIVEN THE LACK OF STRONG INSTABILITY...IT
LOOKS LIKE THIS WILL BE GENERAL SHOWERS. FLOW THEN TURNS
NORTHWESTERLY WITH MUCH COOLER AIR FILTERING INTO THE CWFA. TUE
HIGHS WILL LIKELY STILL TAG THE 80S...WITH TEMPS STRUGGLING TO WARM
BEYOND THE LOW/MID 70S WED/THUR. BROAD SFC RIDGE THEN QUICKLY BUILDS
IN WED NGT/THUR...WITH PLEASANT AND LESS HUMID CONDS DEVELOPING.
CONFIDENCE...HIGH.
FRIDAY THROUGH SUNDAY...
ENSEMBLES CONTINUE TO SUGGEST THAT THE PATTERN MAY BE ADJUSTING FOR
THE END OF THE WEEK/WEEKEND WITH A RIDGE BUILDING INTO THE CANADIAN
ROCKIES...WHICH WOULD ALLOW A DOWNSTREAM TROUGH ACROSS THE GREAT
LAKES/NORTHEAST CONUS. IN CONCERT WITH THE RIDGE OUT WEST...THERMAL
TEMPS ARE PROGGED TO SOAR WELL ABOVE NORMAL IN THE WEST AS WELL.
THIS WILL LIKELY AID IN MORE SEASONAL TEMPS FOR THE OUR FORECAST
AREA WITH TEMPS GENERALLY IN THE 70S TO POSSIBLY MID 80S. WHILE IT
LOOKS LIKE A DRY WEEKEND IS IN STORE FOR THE CWFA...IT IS POSSIBLE A
WEAK WAVE COULD SLIDE SOUTHEAST TOWARDS THE REGION AND GENERATE SOME
LOW CHC POPS.
CONFIDENCE...HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* TSRA 08Z-10Z EARLY THIS MORNING.
* LOW MVFR CIGS THROUGH MID MORNING.
* STRONG/GUSTY SOUTH/SOUTHWEST WINDS FROM MID/LATE MORNING THROUGH
MID EVENING.
* TSRA LATE AFTERNOON THROUGH MID EVENING WITH STRONG/ERRATIC
WINDS/HEAVY RAIN. CMS
//DISCUSSION...UPDATED 06Z...
LINE OF TSRA WILL MOVE ACROSS THE TERMINALS EARLY THIS MORNING
WITH SOME WEAKENING EXPECTED AS THEY REACH THE SOUTHERN END OF
LAKE MICHIGAN. STRONGEST STORMS WILL PRODUCE TORRENTIAL RAIN AND
STRONG/GUSTY WINDS. DEPENDING ON THE OVERALL EVOLUTION...IT IS
POSSIBLE STRONGEST CELLS MAY MOVE NORTH AND/OR SOUTH OF THE
TERMINALS.
DEWPOINTS BACK IN THE LOWER 70S EARLY THIS MORNING HAVE MAINTAINED
MIXED LOW LEVELS AND EXPECT GUSTY SOUTHERLY WINDS INTO THE MID/UPPER
TEEN RANGE UNTIL TSRA ARRIVE. MVFR CIGS HAVE ALSO DEVELOPED WITH
THESE MOIST LOW LEVELS. POSSIBLE CIGS MAY DIP TO IFR TOWARD
SUNRISE BUT PREVAILING LOWER MVFR CIGS LOOK ON TRACK THROUGH MID
OR POSSIBLY LATE MORNING.
ONCE THE CURRENT ACTIVITY WEAKENS/MOVES EAST OF THE TERMINALS...
EXPECT DRY CONDITIONS THROUGH MID AFTERNOON. TSRA EXPECTED TO
REDEVELOP JUST NORTHWEST OF RFD LATER THIS AFTERNOON WITH A LARGE
COMPLEX OF STORMS EXPECTED TO SPREAD ACROSS NORTHERN IL DURING THE
EARLY/MID EVENING. THESE STORMS WILL LIKELY PRODUCE STRONG/ERRATIC
WIND GUSTS AND TORRENTIAL RAIN WITH IFR/LIFR CIGS/VIS. MAINTAINED
TIMING FROM PREVIOUS FORECAST WHICH APPEARS TO BE THE BEST TIME
PERIOD...BUT SOME REFINEMENT CAN BE EXPECTED WITH LATER FORECASTS.
GUSTY SOUTHERLY WINDS WILL DEVELOP DURING THE MID/LATE MORNING
HOURS AND STRENGTHEN DURING THE AFTERNOON. FORECAST SOUNDINGS
SUGGEST THAT SOUTH/SOUTHWEST WINDS MAY BECOME QUITE STRONG BY MID
TO LATE AFTERNOON WITH GUSTS POSSIBLY EXCEEDING 30KTS. NOT TOO
CONFIDENT HOW STRONG WINDS WILL BECOME DURING THE LATE AFTERNOON
BUT DID BUMP SPEEDS/GUSTS UP A BIT. CMS
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH FOR TSRA EARLY THIS MORNING.
* HIGH FOR MVFR CIGS THROUGH MID MORNING.
* MEDIUM FOR WIND SPEEDS/GUSTS THROUGH THE PERIOD.
* HIGH FOR TSRA LATE AFTERNOON THROUGH MID EVENING...MEDIUM ON
TIMING. CMS
//OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z...
TUESDAY...VFR.
WEDNESDAY...SLIGHT CHANCE OF SHRA AND MVFR.
THURSDAY-SATURDAY...VFR LIKELY.
MTF
&&
.MARINE...
212 PM CDT
UNSEASONABLY STRONG LOW PRESSURE SYSTEM LIES OVER MANITOBA THIS
AFTERNOON WITH MODERATE SOUTHERLY FLOW ACROSS LAKE MICHIGAN.
STABLE CONDITIONS OVER THE LAKE ARE HELPING TO KEEP THE WINDS IN
CHECK TO SOME DEGREE...BUT SOME SHIPS HAVE REPORTED WINDS TO
AROUND 30 KT SO FAR TODAY. THE GRADIENT WILL BE MAINTAINED THROUGH
TUESDAY WITH THE MODERATE WINDS CONTINUING THROUGH THIS PERIOD.
WINDS WILL BE CLOSE TO SMALL CRAFT ADVISORY CRITERIA BOTH ON
MONDAY AND AGAIN TUESDAY. ALSO...DEWPOINTS INTO THE 60S HAVE BEEN
TRANSPORTED INTO THE GREAT LAKES REGION AND CONTINUES TO RESULT IN
FOG ESPECIALLY ACROSS THE NORTH HALF OF THE LAKE. THERE IS NO
CLEAR REASON FOR THE FOG TO DISSIPATE UNTIL LATER TUESDAY INTO
WEDNESDAY WHEN A COLD FRONT SWEEPS ACROSS THE LAKE. WILL EXTEND
THE FOG ADVISORY FOR NORTHERN LAKE MICHIGAN INTO MONDAY
AFTERNOON...BUT IT MAY BE NEEDED FOR ANOTHER 24 HOURS OR SO BEYOND
THAT EVEN.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ868 UNTIL 9 PM MONDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1233 AM CDT MON JUN 30 2014
.MESOSCALE DISCUSSION...
1210 AM CDT
BROKEN LINE OF CONVECTION CONTINUES TO MOVE EAST ACROSS SOUTHERN
WISCONSIN...WHILE FURTHER SOUTH A MORE WEST-EAST ORIENTED SEGMENT
IS STARTING TO SHOW SOME BOWING JUST NORTH OF THE QUAD CITIES.
SURFACE TEMPERATURES IN THE UPPER 70S WITH MID 70S DEW POINTS
INCLUDING REGULAR GUSTS ACROSS NORTHWEST IL ARE SUPPORTING OF
SURFACE-BASED ACTIVITY AND HAVE SEEN THIS REFLECTED IN RADAR THE
PAST COUPLE HOURS ALONG WITH TWO POTENTIAL TORNADO REPORTS FROM
THE MKX AND DVN CWAS. THE LOW-LEVEL SHEAR AND HELICITY ARE
STRONG...AROUND 25-30 KT AND 200-250 M2/S2 BASED ON THE DVN VAD
PROFILE. SO THE ENVIRONMENT REMAINS FAVORABLE FOR POSSIBLE LOW-
LEVEL ROTATION IN ANY SUPERCELL STRUCTURES AS WELL AS THE ABILITY
TO STRENGTHEN BOWING SEGMENTS. RADAR TRENDS IN THE PAST HALF HOUR
HAVE SHOWN SIGNS OF A LITTLE MORE OUTFLOW DRIVEN STORMS/SEGMENTS
WITHIN THE BROKEN LINE...INDICATING MORE OF A WIND
THREAT...THROUGH SOME REGULARLY MODEST BOOKEND VORTICY SIGNATURES
INCLUDING NEAR THE WISCONSIN/ILLINOIS STATE LINE NORTH OF ROCKFORD
AND NEAR CLINTON AS OF 1210 AM.
COMPARING VAD PROFILES BETWEEN DMX AND DVN IT IS CLEAR THERE IS A
MID-LEVEL WAVE...LIKELY CONVECTIVELY ENHANCED...THAT IS HELPING
TO KEEP THIS ACTIVITY ROBUST...ALONG WITH UPPER JET SUPPORT. THIS
WAVE SHOULD ALSO HELP TO MOVE STORMS ALONG EASTWARD...ALONG WITH
THE VEERING OF THE LOW-LEVEL JET THOUGH SOME BACKBUILDING HAS BEEN
SEEN. CONVECTION SHOULD STILL SEE A VERY SLOW WEAKENING
TREND...LIKELY MORE SO AS IT NEARS CHICAGO DUE TO A STRONGER
INVERSION. IF HOWEVER CONVECTION IS ORGANIZED WITH A SUSTAINING
COLD POOL...THEN A SEVERE WEATHER THREAT WILL BE MORE LIKELY
FURTHER EAST THAN CURRENT WATCH.
MTF
&&
.DISCUSSION...
801 PM CDT
ALL ATTENTION THIS EVENING IS FOCUSED ON THE RATHER IMPRESSIVE
ONGOING CONVECTION ACROSS IOWA.
IT APPEARS THAT ALTHOUGH LARGE SCALE FORCING FOR ASCENT IS RATHER
WEAK...THAT THE CONVECTIVE ACTIVITY WILL CONTINUE TO DEVELOP/MAINTAIN
ITSELF ACROSS CENTRAL AND EASTERN SECTIONS OF IOWA THROUGH THIS
EVENING AS THE LOW LEVEL JET INCREASES. THE MAIN CONCERNS FOR MY
AREA IS IF ANY OF THIS ACTIVITY WILL BUILD UPSCALE INTO ANY FORWARD
PROPAGATING SEGMENTS. UNFORTUNATELY CONFIDENCE REMAINS LOW WITH THIS
POSSIBILITY. HOWEVER...IF THIS WERE TO OCCUR...THE CORFIDI FORWARD
PROPAGATING VECTORS SUGGEST THAT THE FORWARD PROPAGATING SEGMENTS
WOULD FAVOR A NEARLY DUE EASTERLY MOVEMENT. THIS WOULD SUGGEST THAT
FAR NORTHERN ILLINOIS WOULD BE THE MOST LIKELY CANDIDATES FOR THIS
ACTIVITY LATER TONIGHT AFTER MIDNIGHT. THE 00 UTC SOUNDING OUT OF
KDVN INDICATES THE PRESENCE OF A STRONGLY UNSTABLE ENVIRONMENT...WITH
JUST OVER 3800 J/KG OF SBCAPE...THANKS TO THE PRESENCE OF VERY STEEP
MID LEVEL LAPSE RATES ASSOCIATED WITH AN EML. ALTHOUGH THIS EML IS
ACTING AS A CAP CURRENTLY...ONCE STORMS EVOLVE EASTWARD...THE DRY
AIR IN THE MID LEVELS SUGGESTS THE POTENTIAL OF OUTFLOW DOMINATE
STORMS...WHICH WOULD CERTAINLY FAVOR THE POTENTIAL FOR FORWARD
PROPAGATING CONVECTIVE ELEMENTS CAPABLE OF PRODUCING DAMAGING
WINDS AND POSSIBLY SOME LARGE HAIL...ESPECIALLY CONSIDERING THE
PRESENCE OF NEARLY 50 KT OF MID LEVEL WESTERLY FLOW.
THE MAIN WILDCARD TO THIS POSSIBILITY OF CONVECTION MOVING ACROSS
NORTHERN ILLINOIS TONIGHT WILL BE IF AND HOW THE CONVECTIVE ACTIVITY
EXPECTED FARTHER SOUTH ACROSS MISSOURI TONIGHT AFFECTS THE MOISTURE
TRANSPORT INTO NORTHERN ILLINOIS. MODEL GUIDANCE DOES SUGGEST THAT
THE PORTIONS OF MISSOURI WILL RESIDE ALONG THE NOSE OF THE LOW LEVEL
JET TONIGHT...AND THIS COMBINED WITH THE PRESENCE OF A CONVECTIVELY
ENHANCED SHORT WAVE ACROSS EASTERN KANSAS...COULD FAVOR CONVECTIVE
ACTIVITY TO THRIVE IN MISSOURI TONIGHT. IN RETURN...THIS COULD ACT
TO ROB THE MOISTURE TRANSPORT FROM STORMS MOVING INTO NORTHERN
ILLINOIS...WHICH COULD CAUSE THEM TO WEAKEN AS THEY SHIFT EASTWARD
OVERNIGHT.
GIVEN THE UNCERTAINTY IN WHICH SCENARIO WILL PLAY OUT...I HAVE CHOSEN
TO NOT MAKE ANY BIG CHANGES TO THE GOING POPS AT THIS TIME. OUR
CURRENT FORECAST PLACES THE HIGHEST CHANCES ACROSS NORTH CENTRAL
ILLINOIS FROM 6 TO 9 UTC TONIGHT...WHICH STILL SEEMS
REASONABLE.
THE SEVERE WEATHER THREAT CONTINUES TO LOOK THE GREATEST FOR LATE
MONDAY AFTERNOON AND EVENING.
KJB
//PREV DISCUSSION...
204 PM CDT
TONIGHT...
LINGERING STRATUS CLOUDS FINALLY BURNED OFF LATE THIS MORNING...WITH
SOME SCATTERED CUMULUS DEVELOPING EARLY THIS AFTN. VISIBLE IMAGERY
INDICATES SOME OF THE CU FIELD WAS BECOMING AGITATED AND TRYING TO
BUILD SOUTH OF I-80 THIS AFTN...WHICH WAS THE REGION WHERE BETTER
MOISTURE WAS AVAILABLE AS DEW POINTS LINGERED ARND 70 TO LOW 70S.
THE STRONGER WAVE WAS STILL WELL WEST OF THE CWFA INTO
CENTRAL/WESTERN IOWA...WITH THE FOCUS FOR STRONG/SEVERE STORMS THIS
AFTN/EVE WILL RESIDE. FURTHER EAST ACROSS NORTHERN IL/NORTHWEST
IN...THE ATMOSPHERE WILL STEADILY BECOME MORE UNSTABLE. SOUNDINGS
CONTINUE TO INDICATE A WEAK WARM LAYER ALOFT...HOWEVER IT HAS BEEN
SLIGHTLY COOLER THAN WAS EXPECTED. WHICH WILL LIKELY KEEP TEMPS
SLIGHTLY COOLER THIS AFTN...ALTHOUGH A FEW POINTS ALONG AND SOUTH OF
LASALLE TO VALPARAISO COULD STILL TAG 90 THIS AFTN. OTHERWISE TEMPS
SHUD TOP OUT IN THE MID TO PERHAPS UPR 80S.
THE STORY FOR TONIGHT WILL BE SHOW OR NO-SHOW IN REGARDS TO
CONVECTION. THEN IN WHAT CAPACITY WILL IT ARRIVE ACROSS A PORTION OF
OUR CWFA TONIGHT/EARLY MON. LATEST RAP SOUNDINGS WOULD SUGGEST WE
ARE SITTING ON ABOUT 2K J/KG OF CAPE...UNFORTUNATELY A WARM LAYER
ALOFT WILL LIKELY KEEP CONVECTIVE COVERAGE TO A MINIMA THRU AT LEAST
23Z. UPSTREAM THE SPC MESOANALYSIS INDICATES THE INHIBITION OVER
CENTRAL IA SHUD BEGIN TO DISSOLVE BY 20-21Z...AND EXPECT AN UPTICK
IN CONVECTIVE GROWTH THERE. LOCAL ARW8KM SOLUTION HAS A SIMILAR WARM
LAYER ALOFT...WHICH WILL LIKELY ACT AS A CAP AND COULD LINGER TO
ARND 00Z MON TO POSSIBLY 04Z.
UTILIZING THE BUNKER STORM MOTION...IT APPEARS THAT IF CONVECTION
CAN DEVELOP UPSTREAM IT WOULD SLIDE EAST TOWARDS THE CENTRAL CWFA
THEN TURN SOUTHEAST CLIPPING THE SOUTHERN CWFA. BUT THE QUESTION
REMAINS WILL CONVECTION BE ABLE TO MAINTAIN ITSELF INTO THE CWFA
TONIGHT...AND WITH THE STRENGTHENING PUSH OF WARM AIR ALOFT THIS
LOOKS TO BE CHALLENGING.
EXPECT TEMPS TO REMAIN MILD WITH LOWS IN THE LOW 70S.
MONDAY...
THIS CONTINUES TO BE THE DAY OF GREATEST CONCERN FOR STRONG/SEVERE
STORMS. THE TIMING FOR CONVECTIVE DEVELOPMENT LOOKS TO BE FOCUSED IN
THE AFTN/EVE TIMEFRAME. THE DAY SHUD START OFF WITH SOME SCT SHOWERS
POSSIBLY AN ISOLATED STORM OR TWO. PROFILES INDICATE STEEPENING
LAPSE RATES BY EARLY AFTN...HOWEVER THERE IS STILL A SIZABLE PUSH
OF WARM AIR ALOFT THAT COULD KEEP THINGS CAPPED YET AGAIN THRU
21-22Z MON. GUIDANCE CONTINUES TO SUGGEST THE WAVE OVER IOWA ALONG
THE LEADING EDGE OF A MID-LVL TROUGH/VORT TO BE THE FOCAL POINT.
THIS FEATURE IS PROGGED TO ARRIVE OVER THE FORECAST AREA AFT
21Z...SO THE TIMING OF LATE AFTN/EVE FOR GREATEST CONVECTIVE GROWTH
AND COVERAGE REMAINS IN PLACE. STORM MOTION MON EVE LOOKS TO BE
PUSHING EAST THEN BEGIN TURNING SOUTHEAST. AT THIS TIME SPC HAS THE
ENTIRE AREA OUTLOOKED FOR SLIGHT RISK...WITH THE GREATEST HAZARDS
BEING LARGE HAIL AND DAMAGING WINDS.
TEMPS MON WILL HINGE UPON THE MORNING CLOUD COVERAGE AND HOW QUICKLY
THAT CAN ERODE. AT THIS TIME IT APPEARS TEMPS SHUD PUSH INTO THE
MID/UPR 80S WITH DEW PTS IN THE LOW 70S. THE COMBINATION WILL CREATE
HEAT INDEX VALUES IN THE MID/UPR 90S.
TUESDAY THROUGH THURSDAY...
DRY SLOT QUICKLY ARRIVES BEHIND THE VORT PASSAGE TUE...WHICH SHUD
ALLOW MUCH OF TUE TO BE DRY. LLVL FLOW WILL REMAIN SOUTHWESTERLY
WITH A MORE ROBUST MID-LVL TROUGH JUST UPSTREAM ACROSS THE NORTHERN
PLAINS THAT WILL ARRIVE ACROSS THE REGION WED. ANOTHER LOBE OF
VORTICITY IS PROGGED TO PIVOT OVERHEAD WED MORNING...AND WILL BRING
ANOTHER CHC FOR PRECIP. GIVEN THE LACK OF STRONG INSTABILITY...IT
LOOKS LIKE THIS WILL BE GENERAL SHOWERS. FLOW THEN TURNS
NORTHWESTERLY WITH MUCH COOLER AIR FILTERING INTO THE CWFA. TUE
HIGHS WILL LIKELY STILL TAG THE 80S...WITH TEMPS STRUGGLING TO WARM
BEYOND THE LOW/MID 70S WED/THUR. BROAD SFC RIDGE THEN QUICKLY BUILDS
IN WED NGT/THUR...WITH PLEASANT AND LESS HUMID CONDS DEVELOPING.
CONFIDENCE...HIGH.
FRIDAY THROUGH SUNDAY...
ENSEMBLES CONTINUE TO SUGGEST THAT THE PATTERN MAY BE ADJUSTING FOR
THE END OF THE WEEK/WEEKEND WITH A RIDGE BUILDING INTO THE CANADIAN
ROCKIES...WHICH WOULD ALLOW A DOWNSTREAM TROUGH ACROSS THE GREAT
LAKES/NORTHEAST CONUS. IN CONCERT WITH THE RIDGE OUT WEST...THERMAL
TEMPS ARE PROGGED TO SOAR WELL ABOVE NORMAL IN THE WEST AS WELL.
THIS WILL LIKELY AID IN MORE SEASONAL TEMPS FOR THE OUR FORECAST
AREA WITH TEMPS GENERALLY IN THE 70S TO POSSIBLY MID 80S. WHILE IT
LOOKS LIKE A DRY WEEKEND IS IN STORE FOR THE CWFA...IT IS POSSIBLE A
WEAK WAVE COULD SLIDE SOUTHEAST TOWARDS THE REGION AND GENERATE SOME
LOW CHC POPS.
CONFIDENCE...HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* TSRA 08Z-10Z EARLY THIS MORNING.
* LOW MVFR CIGS THROUGH MID MORNING.
* STRONG/GUSTY SOUTH/SOUTHWEST WINDS FROM MID/LATE MORNING THROUGH
MID EVENING.
* TSRA LATE AFTERNOON THROUGH MID EVENING WITH STRONG/ERRATIC
WINDS/HEAVY RAIN. CMS
//DISCUSSION...UPDATED 06Z...
LINE OF TSRA WILL MOVE ACROSS THE TERMINALS EARLY THIS MORNING
WITH SOME WEAKENING EXPECTED AS THEY REACH THE SOUTHERN END OF
LAKE MICHIGAN. STRONGEST STORMS WILL PRODUCE TORRENTIAL RAIN AND
STRONG/GUSTY WINDS. DEPENDING ON THE OVERALL EVOLUTION...IT IS
POSSIBLE STRONGEST CELLS MAY MOVE NORTH AND/OR SOUTH OF THE
TERMINALS.
DEWPOINTS BACK IN THE LOWER 70S EARLY THIS MORNING HAVE MAINTAINED
MIXED LOW LEVELS AND EXPECT GUSTY SOUTHERLY WINDS INTO THE MID/UPPER
TEEN RANGE UNTIL TSRA ARRIVE. MVFR CIGS HAVE ALSO DEVELOPED WITH
THESE MOIST LOW LEVELS. POSSIBLE CIGS MAY DIP TO IFR TOWARD
SUNRISE BUT PREVAILING LOWER MVFR CIGS LOOK ON TRACK THROUGH MID
OR POSSIBLY LATE MORNING.
ONCE THE CURRENT ACTIVITY WEAKENS/MOVES EAST OF THE TERMINALS...
EXPECT DRY CONDITIONS THROUGH MID AFTERNOON. TSRA EXPECTED TO
REDEVELOP JUST NORTHWEST OF RFD LATER THIS AFTERNOON WITH A LARGE
COMPLEX OF STORMS EXPECTED TO SPREAD ACROSS NORTHERN IL DURING THE
EARLY/MID EVENING. THESE STORMS WILL LIKELY PRODUCE STRONG/ERRATIC
WIND GUSTS AND TORRENTIAL RAIN WITH IFR/LIFR CIGS/VIS. MAINTAINED
TIMING FROM PREVIOUS FORECAST WHICH APPEARS TO BE THE BEST TIME
PERIOD...BUT SOME REFINEMENT CAN BE EXPECTED WITH LATER FORECASTS.
GUSTY SOUTHERLY WINDS WILL DEVELOP DURING THE MID/LATE MORNING
HOURS AND STRENGTHEN DURING THE AFTERNOON. FORECAST SOUNDINGS
SUGGEST THAT SOUTH/SOUTHWEST WINDS MAY BECOME QUITE STRONG BY MID
TO LATE AFTERNOON WITH GUSTS POSSIBLY EXCEEDING 30KTS. NOT TOO
CONFIDENT HOW STRONG WINDS WILL BECOME DURING THE LATE AFTERNOON
BUT DID BUMP SPEEDS/GUSTS UP A BIT. CMS
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH FOR TSRA EARLY THIS MORNING.
* HIGH FOR MVFR CIGS THROUGH MID MORNING.
* MEDIUM FOR WIND SPEEDS/GUSTS THROUGH THE PERIOD.
* HIGH FOR TSRA LATE AFTERNOON THROUGH MID EVENING...MEDIUM ON
TIMING. CMS
//OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z...
TUESDAY...VFR.
WEDNESDAY...SLIGHT CHANCE OF SHRA AND MVFR.
THURSDAY-SATURDAY...VFR LIKELY.
MTF
&&
.MARINE...
212 PM CDT
UNSEASONABLY STRONG LOW PRESSURE SYSTEM LIES OVER MANITOBA THIS
AFTERNOON WITH MODERATE SOUTHERLY FLOW ACROSS LAKE MICHIGAN.
STABLE CONDITIONS OVER THE LAKE ARE HELPING TO KEEP THE WINDS IN
CHECK TO SOME DEGREE...BUT SOME SHIPS HAVE REPORTED WINDS TO
AROUND 30 KT SO FAR TODAY. THE GRADIENT WILL BE MAINTAINED THROUGH
TUESDAY WITH THE MODERATE WINDS CONTINUING THROUGH THIS PERIOD.
WINDS WILL BE CLOSE TO SMALL CRAFT ADVISORY CRITERIA BOTH ON
MONDAY AND AGAIN TUESDAY. ALSO...DEWPOINTS INTO THE 60S HAVE BEEN
TRANSPORTED INTO THE GREAT LAKES REGION AND CONTINUES TO RESULT IN
FOG ESPECIALLY ACROSS THE NORTH HALF OF THE LAKE. THERE IS NO
CLEAR REASON FOR THE FOG TO DISSIPATE UNTIL LATER TUESDAY INTO
WEDNESDAY WHEN A COLD FRONT SWEEPS ACROSS THE LAKE. WILL EXTEND
THE FOG ADVISORY FOR NORTHERN LAKE MICHIGAN INTO MONDAY
AFTERNOON...BUT IT MAY BE NEEDED FOR ANOTHER 24 HOURS OR SO BEYOND
THAT EVEN.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ868 UNTIL 9 PM MONDAY.
&&
$$
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AREA FORECAST DISCUSSION...UPDATED
NWS CHICAGO/ROMEOVILLE IL
1215 AM CDT MON JUN 30 2014
.MESOSCALE DISCUSSION...
1210 AM CDT
BROKEN LINE OF CONVECTION CONTINUES TO MOVE EAST ACROSS SOUTHERN
WISCONSIN...WHILE FURTHER SOUTH A MORE WEST-EAST ORIENTED SEGMENT
IS STARTING TO SHOW SOME BOWING JUST NORTH OF THE QUAD CITIES.
SURFACE TEMPERATURES IN THE UPPER 70S WITH MID 70S DEW POINTS
INCLUDING REGULAR GUSTS ACROSS NORTHWEST IL ARE SUPPORTING OF
SURFACE-BASED ACTIVITY AND HAVE SEEN THIS REFLECTED IN RADAR THE
PAST COUPLE HOURS ALONG WITH TWO POTENTIAL TORNADO REPORTS FROM
THE MKX AND DVN CWAS. THE LOW-LEVEL SHEAR AND HELICITY ARE
STRONG...AROUND 25-30 KT AND 200-250 M2/S2 BASED ON THE DVN VAD
PROFILE. SO THE ENVIRONMENT REMAINS FAVORABLE FOR POSSIBLE LOW-
LEVEL ROTATION IN ANY SUPERCELL STRUCTURES AS WELL AS THE ABILITY
TO STRENGTHEN BOWING SEGMENTS. RADAR TRENDS IN THE PAST HALF HOUR
HAVE SHOWN SIGNS OF A LITTLE MORE OUTFLOW DRIVEN STORMS/SEGMENTS
WITHIN THE BROKEN LINE...INDICATING MORE OF A WIND
THREAT...THROUGH SOME REGULARLY MODEST BOOKEND VORTICY SIGNATURES
INCLUDING NEAR THE WISCONSIN/ILLINOIS STATE LINE NORTH OF ROCKFORD
AND NEAR CLINTON AS OF 1210 AM.
COMPARING VAD PROFILES BETWEEN DMX AND DVN IT IS CLEAR THERE IS A
MID-LEVEL WAVE...LIKELY CONVECTIVELY ENHANCED...THAT IS HELPING
TO KEEP THIS ACTIVITY ROBUST...ALONG WITH UPPER JET SUPPORT. THIS
WAVE SHOULD ALSO HELP TO MOVE STORMS ALONG EASTWARD...ALONG WITH
THE VEERING OF THE LOW-LEVEL JET THOUGH SOME BACKBUILDING HAS BEEN
SEEN. CONVECTION SHOULD STILL SEE A VERY SLOW WEAKENING
TREND...LIKELY MORE SO AS IT NEARS CHICAGO DUE TO A STRONGER
INVERSION. IF HOWEVER CONVECTION IS ORGANIZED WITH A SUSTAINING
COLD POOL...THEN A SEVERE WEATHER THREAT WILL BE MORE LIKELY
FURTHER EAST THAN CURRENT WATCH.
MTF
&&
.DISCUSSION...
801 PM CDT
ALL ATTENTION THIS EVENING IS FOCUSED ON THE RATHER IMPRESSIVE
ONGOING CONVECTION ACROSS IOWA.
IT APPEARS THAT ALTHOUGH LARGE SCALE FORCING FOR ASCENT IS RATHER
WEAK...THAT THE CONVECTIVE ACTIVITY WILL CONTINUE TO DEVELOP/MAINTAIN
ITSELF ACROSS CENTRAL AND EASTERN SECTIONS OF IOWA THROUGH THIS
EVENING AS THE LOW LEVEL JET INCREASES. THE MAIN CONCERNS FOR MY
AREA IS IF ANY OF THIS ACTIVITY WILL BUILD UPSCALE INTO ANY FORWARD
PROPAGATING SEGMENTS. UNFORTUNATELY CONFIDENCE REMAINS LOW WITH THIS
POSSIBILITY. HOWEVER...IF THIS WERE TO OCCUR...THE CORFIDI FORWARD
PROPAGATING VECTORS SUGGEST THAT THE FORWARD PROPAGATING SEGMENTS
WOULD FAVOR A NEARLY DUE EASTERLY MOVEMENT. THIS WOULD SUGGEST THAT
FAR NORTHERN ILLINOIS WOULD BE THE MOST LIKELY CANDIDATES FOR THIS
ACTIVITY LATER TONIGHT AFTER MIDNIGHT. THE 00 UTC SOUNDING OUT OF
KDVN INDICATES THE PRESENCE OF A STRONGLY UNSTABLE ENVIRONMENT...WITH
JUST OVER 3800 J/KG OF SBCAPE...THANKS TO THE PRESENCE OF VERY STEEP MID
LEVEL LAPSE RATES ASSOCIATED WITH AN EML. ALTHOUGH THIS EML IS
ACTING AS A CAP CURRENTLY...ONCE STORMS EVOLVE EASTWARD...THE DRY
AIR IN THE MID LEVELS SUGGESTS THE POTENTIAL OF OUTFLOW DOMINATE
STORMS...WHICH WOULD CERTAINLY FAVOR THE POTENTIAL FOR FORWARD
PROPAGATING CONVECTIVE ELEMENTS CAPABLE OF PRODUCING DAMAGING
WINDS AND POSSIBLY SOME LARGE HAIL...ESPECIALLY CONSIDERING THE
PRESENCE OF NEARLY 50 KT OF MID LEVEL WESTERLY FLOW.
THE MAIN WILDCARD TO THIS POSSIBILITY OF CONVECTION MOVING ACROSS
NORTHERN ILLINOIS TONIGHT WILL BE IF AND HOW THE CONVECTIVE ACTIVITY
EXPECTED FARTHER SOUTH ACROSS MISSOURI TONIGHT AFFECTS THE MOISTURE
TRANSPORT INTO NORTHERN ILLINOIS. MODEL GUIDANCE DOES SUGGEST THAT
THE PORTIONS OF MISSOURI WILL RESIDE ALONG THE NOSE OF THE LOW LEVEL
JET TONIGHT...AND THIS COMBINED WITH THE PRESENCE OF A CONVECTIVELY
ENHANCED SHORT WAVE ACROSS EASTERN KANSAS...COULD FAVOR CONVECTIVE
ACTIVITY TO THRIVE IN MISSOURI TONIGHT. IN RETURN...THIS COULD ACT
TO ROB THE MOISTURE TRANSPORT FROM STORMS MOVING INTO NORTHERN
ILLINOIS...WHICH COULD CAUSE THEM TO WEAKEN AS THEY SHIFT EASTWARD
OVERNIGHT.
GIVEN THE UNCERTAINTY IN WHICH SCENARIO WILL PLAY OUT...I HAVE CHOSEN
TO NOT MAKE ANY BIG CHANGES TO THE GOING POPS AT THIS TIME. OUR
CURRENT FORECAST PLACES THE HIGHEST CHANCES ACROSS NORTH CENTRAL
ILLINOIS FROM 6 TO 9 UTC TONIGHT...WHICH STILL SEEMS
REASONABLE.
THE SEVERE WEATHER THREAT CONTINUES TO LOOK THE GREATEST FOR LATE
MONDAY AFTERNOON AND EVENING.
KJB
//PREV DISCUSSION...
204 PM CDT
TONIGHT...
LINGERING STRATUS CLOUDS FINALLY BURNED OFF LATE THIS MORNING...WITH
SOME SCATTERED CUMULUS DEVELOPING EARLY THIS AFTN. VISIBLE IMAGERY
INDICATES SOME OF THE CU FIELD WAS BECOMING AGITATED AND TRYING TO
BUILD SOUTH OF I-80 THIS AFTN...WHICH WAS THE REGION WHERE BETTER
MOISTURE WAS AVAILABLE AS DEW POINTS LINGERED ARND 70 TO LOW 70S.
THE STRONGER WAVE WAS STILL WELL WEST OF THE CWFA INTO
CENTRAL/WESTERN IOWA...WITH THE FOCUS FOR STRONG/SEVERE STORMS THIS
AFTN/EVE WILL RESIDE. FURTHER EAST ACROSS NORTHERN IL/NORTHWEST
IN...THE ATMOSPHERE WILL STEADILY BECOME MORE UNSTABLE. SOUNDINGS
CONTINUE TO INDICATE A WEAK WARM LAYER ALOFT...HOWEVER IT HAS BEEN
SLIGHTLY COOLER THAN WAS EXPECTED. WHICH WILL LIKELY KEEP TEMPS
SLIGHTLY COOLER THIS AFTN...ALTHOUGH A FEW POINTS ALONG AND SOUTH OF
LASALLE TO VALPARAISO COULD STILL TAG 90 THIS AFTN. OTHERWISE TEMPS
SHUD TOP OUT IN THE MID TO PERHAPS UPR 80S.
THE STORY FOR TONIGHT WILL BE SHOW OR NO-SHOW IN REGARDS TO
CONVECTION. THEN IN WHAT CAPACITY WILL IT ARRIVE ACROSS A PORTION OF
OUR CWFA TONIGHT/EARLY MON. LATEST RAP SOUNDINGS WOULD SUGGEST WE
ARE SITTING ON ABOUT 2K J/KG OF CAPE...UNFORTUNATELY A WARM LAYER
ALOFT WILL LIKELY KEEP CONVECTIVE COVERAGE TO A MINIMA THRU AT LEAST
23Z. UPSTREAM THE SPC MESOANALYSIS INDICATES THE INHIBITION OVER
CENTRAL IA SHUD BEGIN TO DISSOLVE BY 20-21Z...AND EXPECT AN UPTICK
IN CONVECTIVE GROWTH THERE. LOCAL ARW8KM SOLUTION HAS A SIMILAR WARM
LAYER ALOFT...WHICH WILL LIKELY ACT AS A CAP AND COULD LINGER TO
ARND 00Z MON TO POSSIBLY 04Z.
UTILIZING THE BUNKER STORM MOTION...IT APPEARS THAT IF CONVECTION
CAN DEVELOP UPSTREAM IT WOULD SLIDE EAST TOWARDS THE CENTRAL CWFA
THEN TURN SOUTHEAST CLIPPING THE SOUTHERN CWFA. BUT THE QUESTION
REMAINS WILL CONVECTION BE ABLE TO MAINTAIN ITSELF INTO THE CWFA
TONIGHT...AND WITH THE STRENGTHENING PUSH OF WARM AIR ALOFT THIS
LOOKS TO BE CHALLENGING.
EXPECT TEMPS TO REMAIN MILD WITH LOWS IN THE LOW 70S.
MONDAY...
THIS CONTINUES TO BE THE DAY OF GREATEST CONCERN FOR STRONG/SEVERE
STORMS. THE TIMING FOR CONVECTIVE DEVELOPMENT LOOKS TO BE FOCUSED IN
THE AFTN/EVE TIMEFRAME. THE DAY SHUD START OFF WITH SOME SCT SHOWERS
POSSIBLY AN ISOLATED STORM OR TWO. PROFILES INDICATE STEEPENING
LAPSE RATES BY EARLY AFTN...HOWEVER THERE IS STILL A SIZABLE PUSH
OF WARM AIR ALOFT THAT COULD KEEP THINGS CAPPED YET AGAIN THRU
21-22Z MON. GUIDANCE CONTINUES TO SUGGEST THE WAVE OVER IOWA ALONG
THE LEADING EDGE OF A MID-LVL TROUGH/VORT TO BE THE FOCAL POINT.
THIS FEATURE IS PROGGED TO ARRIVE OVER THE FORECAST AREA AFT
21Z...SO THE TIMING OF LATE AFTN/EVE FOR GREATEST CONVECTIVE GROWTH
AND COVERAGE REMAINS IN PLACE. STORM MOTION MON EVE LOOKS TO BE
PUSHING EAST THEN BEGIN TURNING SOUTHEAST. AT THIS TIME SPC HAS THE
ENTIRE AREA OUTLOOKED FOR SLIGHT RISK...WITH THE GREATEST HAZARDS
BEING LARGE HAIL AND DAMAGING WINDS.
TEMPS MON WILL HINGE UPON THE MORNING CLOUD COVERAGE AND HOW QUICKLY
THAT CAN ERODE. AT THIS TIME IT APPEARS TEMPS SHUD PUSH INTO THE
MID/UPR 80S WITH DEW PTS IN THE LOW 70S. THE COMBINATION WILL CREATE
HEAT INDEX VALUES IN THE MID/UPR 90S.
TUESDAY THROUGH THURSDAY...
DRY SLOT QUICKLY ARRIVES BEHIND THE VORT PASSAGE TUE...WHICH SHUD
ALLOW MUCH OF TUE TO BE DRY. LLVL FLOW WILL REMAIN SOUTHWESTERLY
WITH A MORE ROBUST MID-LVL TROUGH JUST UPSTREAM ACROSS THE NORTHERN
PLAINS THAT WILL ARRIVE ACROSS THE REGION WED. ANOTHER LOBE OF
VORTICITY IS PROGGED TO PIVOT OVERHEAD WED MORNING...AND WILL BRING
ANOTHER CHC FOR PRECIP. GIVEN THE LACK OF STRONG INSTABILITY...IT
LOOKS LIKE THIS WILL BE GENERAL SHOWERS. FLOW THEN TURNS
NORTHWESTERLY WITH MUCH COOLER AIR FILTERING INTO THE CWFA. TUE
HIGHS WILL LIKELY STILL TAG THE 80S...WITH TEMPS STRUGGLING TO WARM
BEYOND THE LOW/MID 70S WED/THUR. BROAD SFC RIDGE THEN QUICKLY BUILDS
IN WED NGT/THUR...WITH PLEASANT AND LESS HUMID CONDS DEVELOPING.
CONFIDENCE...HIGH.
FRIDAY THROUGH SUNDAY...
ENSEMBLES CONTINUE TO SUGGEST THAT THE PATTERN MAY BE ADJUSTING FOR
THE END OF THE WEEK/WEEKEND WITH A RIDGE BUILDING INTO THE CANADIAN
ROCKIES...WHICH WOULD ALLOW A DOWNSTREAM TROUGH ACROSS THE GREAT
LAKES/NORTHEAST CONUS. IN CONCERT WITH THE RIDGE OUT WEST...THERMAL
TEMPS ARE PROGGED TO SOAR WELL ABOVE NORMAL IN THE WEST AS WELL.
THIS WILL LIKELY AID IN MORE SEASONAL TEMPS FOR THE OUR FORECAST
AREA WITH TEMPS GENERALLY IN THE 70S TO POSSIBLY MID 80S. WHILE IT
LOOKS LIKE A DRY WEEKEND IS IN STORE FOR THE CWFA...IT IS POSSIBLE A
WEAK WAVE COULD SLIDE SOUTHEAST TOWARDS THE REGION AND GENERATE SOME
LOW CHC POPS.
CONFIDENCE...HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 03Z...
* LIKELIHOOD FOR SHRA LATE TONIGHT AND POSSIBLE TSRA.
* MVFR CIGS LIKELY DEVELOPING THROUGH TONIGHT AND PERSISTING
MONDAY MORNING.
* NEAR DUE SOUTHERLY GUSTY WINDS ON MONDAY.
* STRONG GUSTY T-STORMS MONDAY EVENING.
//DISCUSSION...UPDATED 00Z...
THE MAIN IMPACT DURING THE TAF PERIOD WILL LIKELY BE TSRA LATE
MONDAY AFTERNOON AND ESPECIALLY EVENING...HOWEVER SEVERAL THINGS
OF NOTE THROUGHOUT THE NEXT 24-30 HOURS. VERY MOIST LOW-LEVEL AIR
CONTINUES TO FEED NORTHWARD ACROSS THE REGION THIS EVENING. WITHIN
THAT MOIST AIR...PATCHES OF MVFR CIGS HAVE DEVELOPED ACROSS
CENTRAL IL AND FEEL SOME OF THIS COULD GET ADVECTED OR DEVELOP
UPSTREAM ACROSS NORTHERN IL LATE TONIGHT AND PERSIST INTO MONDAY
MORNING. THE 00Z DVN WEATHER BALLOON DATA DOES INDICATE A CAP
CONTINUING WHICH SHOULD PREVENT ANY STORM DEVELOPMENT THIS EVE.
OVERNIGHT THOUGH...STORMS ACROSS IA AS OF 00Z SHOULD EVOLVE
EASTWARD AND FEED ON UNSTABLE AIR ALOFT. THESE WILL LIKELY REACH
THE ROCKFORD AREA NEAR OR SHORTLY AFTER 06Z-07Z. IT IS CHALLENGING
TO SAY WHAT COVERAGE WILL BE...AND THAT WILL BE A DETERMINANT FOR
HOW MUCH IF ANY STORMS CAN REACH EASTWARD TO THE CHICAGO
TERMINALS. FOR THAT REASON...CONTINUING VICINITY MENTION.
MONDAY WILL SEE EARLY MORNING CLOUDS LIFT AND LIKELY SCATTER WITH
GUSTY SOUTHERLY WINDS AS ANOMALOUSLY DEEP LOW PRESSURE FOR
SUMMERTIME MOVES EAST FROM THE CENTRAL PLAINS. IN
RESPONSE...ROBUST THUNDERSTORM DEVELOPMENT IS EXPECTED ACROSS THE
EASTERN HALF OF IA INTO SOUTHERN WI AND NORTHWEST IL DURING MID
TO LATE AFTERNOON ON MONDAY. CONFIDENCE IS HIGH IN THIS GIVEN THE
WEATHER PATTERN...THOUGH TIMING COULD VARY BY A COUPLE/FEW HOURS.
THESE STORMS SHOULD TRACK EAST PRESENTING A SEVERE WEATHER
THREAT...ESPECIALLY VERY GUSTY WINDS AS THEY MOVE ACROSS THE
CHICAGOLAND AREA MONDAY EVE.
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* HIGH IN WINDS.
* LOW IN WHETHER TSRA REACHES AIRFIELDS LATE TONIGHT.
* MEDIUM IN MVFR CIGS DEVELOPING LATE TONIGHT/MONDAY MORNING.
* HIGH IN TSRA OCCURRING MONDAY EVENING. MEDIUM IN TIMING.
//OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z...
TUESDAY...VFR.
WEDNESDAY...SLIGHT CHANCE OF SHRA AND MVFR.
THURSDAY-SATURDAY...VFR LIKELY.
MTF
&&
.MARINE...
212 PM CDT
UNSEASONABLY STRONG LOW PRESSURE SYSTEM LIES OVER MANITOBA THIS
AFTERNOON WITH MODERATE SOUTHERLY FLOW ACROSS LAKE MICHIGAN.
STABLE CONDITIONS OVER THE LAKE ARE HELPING TO KEEP THE WINDS IN
CHECK TO SOME DEGREE...BUT SOME SHIPS HAVE REPORTED WINDS TO
AROUND 30 KT SO FAR TODAY. THE GRADIENT WILL BE MAINTAINED THROUGH
TUESDAY WITH THE MODERATE WINDS CONTINUING THROUGH THIS PERIOD.
WINDS WILL BE CLOSE TO SMALL CRAFT ADVISORY CRITERIA BOTH ON
MONDAY AND AGAIN TUESDAY. ALSO...DEWPOINTS INTO THE 60S HAVE BEEN
TRANSPORTED INTO THE GREAT LAKES REGION AND CONTINUES TO RESULT IN
FOG ESPECIALLY ACROSS THE NORTH HALF OF THE LAKE. THERE IS NO
CLEAR REASON FOR THE FOG TO DISSIPATE UNTIL LATER TUESDAY INTO
WEDNESDAY WHEN A COLD FRONT SWEEPS ACROSS THE LAKE. WILL EXTEND
THE FOG ADVISORY FOR NORTHERN LAKE MICHIGAN INTO MONDAY
AFTERNOON...BUT IT MAY BE NEEDED FOR ANOTHER 24 HOURS OR SO BEYOND
THAT EVEN.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ868 UNTIL 9 PM MONDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS TOPEKA KS
342 AM CDT Mon Jun 30 2014
.SHORT TERM...(Today and Tonight)
Issued at 340 AM CDT MON JUN 30 2014
08Z profiler data shows the low level jet of 30 to 40 KTS continues
to gradually veer to the southwest becoming more parallel to the
front across central NEB. Meanwhile, water vapor imagery shows a
shortwave rotating through ID and MT with nearly zonal flow from the
west coast into the central plains. Surface obs indicate a very warm
and moist airmass remains in place across the forecast area.
With the low level jet veering southwest, convergence along the
boundary is likely to diminish. Besides that any convergence along
the boundary for elevated storms should remain to the north of the
area. Therefore think much of the nocturnal precip will remain north
of the forecast area. Will keep a token slight chance across the
northern tier of counties as the light shower activity spreads east.
The shortwave rotating through the mean flow over the northern
plains is expected to help push the cold front south into the area
by this afternoon. With the front lifting a very moist and unstable
airmass, thunderstorms are likely to develop in eastern KS before
moving to the east. Deep layer shear is expected to be sufficient
for supercell storms and low level shear and LCL heights suggest
tornadoes will be possible. The main questions are how widespread
the convection may be and when storms could initiate. Models show a
low level cap over the warm sector around 850 MB until late in the
afternoon, not unlike what was observed yesterday. But eventually
the forecast soundings cool the layer removing any inhibition. It is
unclear as to where the cooling is coming from as winds within the
layer remain from the southwest. Additionally the stronger forcing
associated with the shortwave over the northern plains appears to
remain just north of the forecast area. So am concerned that these
two factors may limit the coverage of storms in the later afternoon
and early evening. Nevertheless any storm that forms could quickly
become severe with a potential for tornadoes due to the instability
greater than 4000 J/kg and shear progged by the models. At this
time, think thunderstorm initiation may occur over eastern KS with
storms moving to the east. The thunderstorm activity is expected to
push south through the night tonight as the front slowly moves
south.
Highs today should be several degrees warmer than yesterday as there
should be less high level clouds to start the day off and models
laying the thermal ridge over into northeast KS along the surface
trough. There is some uncertainty in how deep the boundary layer
will mix and in turn how warm temps will get. The RAP has had a bias
to mixing the boundary layer to deep and feel it is way to warm.
Since there is so much humidity in the air, opted to keep highs in
the lower and middle 90s. This humidity however will cause heat
indices to range from 100 to 105 this afternoon. If it looks like
temps could end up a degree or two warmer with dewpoints holding in
the 70s, a heat advisory may be needed. Lows tonight should fall
into the 60s with some drier air advecting in from the north along
with some weak cold air advection.
.LONG TERM...(Tuesday through Sunday)
Issued at 340 AM CDT MON JUN 30 2014
The previous active days will begin to calm for next week as a
cooler and more stable airmass settles into place. Still maintained
slight chances for thunderstorms Tuesday with the h85 front across
southern Kansas. Best chances for precipitation will reside near the
Kansas and Oklahoma border. Dry northwest flow aloft continues
Wednesday and Thursday as an expansive surface high builds from the
central plains through the Great Lakes. Light northerly sfc winds
around 10 mph Tuesday gradually will shift to the east and southeast
on Friday as the ridge nudges eastward. Upper ridging begins to
break down, tracking a shortwave trough into the central plains on
Friday evening. Mentioned slight chances for thunderstorms over the
northern CWA at this time, where highest lift resides. Confidence
however, in the southward extent to the trough is low at this time.
Periodic thunderstorms may be possible for next weekend as mid level
flow begins quasi-zonal, allowing for weak waves to pass through.
Unseasonably cooler temperatures Tuesday through Thursday, combined
with dewpoint temperatures in the 50s will make it feel much more
pleasant compared to the previous days. Highs behind the front
Tuesday begin in the low to middle 80s. Weak cool advection with the
surface ridge sliding south will lower highs Wednesday and Thursday
to the upper 70s and lower 80s. Overnight lows during this time with
decent radiational cooling and light winds may reach the upper 50s.
Thermal ridge begins to build over western and central KS
Independence Day as southerly flow returns, peaking highs to the low
and middle 80s. Weekend temps are track to return to near 90 degrees
with overnight lows in the upper 60s.
&&
.AVIATION...(For the 06Z TAFs through 06Z Monday Night)
Issued at 1212 AM CDT MON JUN 30 2014
Could see a few periods of briefly lowered visibilities in the
very humid airmass for the next several hours but expect enough
wind to keep this the exception. Enough agreement with cap
breaking with frontal passage for VCTS for a few hours around 22Z.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Wolters
LONG TERM...Bowen
AVIATION...65
AREA FORECAST DISCUSSION
NWS JACKSON KY
150 AM EDT MON JUN 30 2014
.UPDATE...
ISSUED AT 958 PM EDT SUN JUN 29 2014
MCV CONTINUES TO SPAWN SCATTERED CONVECTION WEST OF I-75 SO WILL
KEEP WITH A MENTION OF SHOWERS AND ISOLATED STORMS THROUGH THE NIGHT
AS THIS SYSTEM PASSES THROUGH. ONLY SOME MINOR TWEAKS TO PRECIP
TIMING AND RAIN CHANCES WERE MADE...AND TEMPS WERE RAISED A DEGREE
OR TWO WITH AMPLE CLOUD COVER LIKELY KEEPING MOST LOCATIONS IN THE
UPPER 60S TO NEAR 70.
UPDATE ISSUED AT 746 PM EDT SUN JUN 29 2014
INITIAL CONVECTION ON OLD OUTFLOW HAS NOW EXITED THE AREA TO THE
NORTH AND EAST. MCV IS STILL EVIDENT OVER CENTRAL KENTUCKY AS IT
CHURNS TOWARD OUR AREA BUT STILL NOT EXACTLY SURE HOW THIS FEATURE
WILL BEHAVE AS IT CROSSES OUR AREA AFTER SUNSET. WILL STAY THE
COURSE WITH THE INHERITED IDEA OF AN INCREASE IN CONVECTION AGAIN
LATER THIS EVENING AND OVERNIGHT AND WATCH RADAR TRENDS OVER THE NEXT
COUPLE OF HOURS BEFORE ADJUSTING TONIGHT/S FORECAST ANY.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 306 PM EDT SUN JUN 29 2014
OUTFLOW FROM THE WESTERN TN MCS FROM EARLIER TODAY HAS IGNITED
NUMEROUS THUNDERSTORMS ACROSS THE SOUTHWEST PART OF THE FORECAST AREA
AND THESE CONTINUE TO ADVANCE NORTHEAST. STORMS HAVE BEEN MOVING NE
AT ABOUT 14 TO 18 KNOTS THUS LIMITING THE RESIDENCE TIME OF THE
EXTREMELY HEAVY RAIN. HOWEVER ADDITIONAL THUNDERSTORMS CONTINUE TO
DEVELOP UPSTREAM SO LOCALIZED FLASH FLOODING STILL REMAINS A THREAT
WITH PRECIPITABLE WATER IN EXCESS OF 1.6 INCHES. RADAR ESTIMATES OVER
1.5 INCHES IN WHITLEY COUNTY EARLIER THIS AFTERNOON.
WITH LOSS OF DAYTIME HEATING WE EXPECT A DECREASE IN THE SHOWERS AND
THUNDERSTORMS. HOWEVER THE REMNANT MESOSCALE CIRCULATION FROM THE TN
MCS SHOULD MOVE OVER OUR AREA TOWARDS MIDNIGHT. THERE IS SOME
INDICATION THAT THE LOW LEVEL JET WILL INCREASE AFTER 03Z AND THERE
WILL BE AN INCREASE IN 7H UVV. THE GFS IS MUCH MORE AGGRESSIVE WITH
THIS IDEA THAN THE NAM...BUT CONCEPTUALLY AN INCREASE IN CONVECTION
LATER TONIGHT MAKES SENSE. IN FACT THE LATEST HRRR IS ALSO SHOWING A
DECREASE IN CONVECTION EARLY TONIGHT AND THEN AN UPTICK LATER
TONIGHT. HAVE DECIDED TO FOLLOW THIS IDEA IN THE GRIDS...AND NOT
FOLLOW THE TYPICAL DIURNAL PROBABILITY OF PRECIPITATION CYCLE.
FOR MONDAY INTO MONDAY NIGHT WE EXPECT A MORE TYPICAL PATTERN OF
AFTERNOON AND EVENING CONVECTION WITH CONVECTION ENDING DURING THE
OVERNIGHT PERIOD OF MONDAY NIGHT INTO EARLY TUESDAY MORNING.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 306 PM EDT SUN JUN 29 2014
GIVEN THE TIME OF YEAR...MODELS ARE IN FAIRLY GOOD AGREEMENT INTO
NEXT WEEKEND. A RATHER SIGNIFICANT WEATHER CHANGE IS ON TAP FOR THE
END OF THE WEEK...JUST IN TIME FOR THE 4TH OF JULY WEEKEND.
TO START THE PERIOD...HEAT AND HUMIDITY WILL REMAIN IN PLACE ON
TUESDAY. A WEAKENING FRONTAL BOUNDARY WILL DROP IN FROM THE
NORTHWEST BY THE AFTERNOON HOURS. GIVEN THE INSTABILITY
EXPECTED...THIS SUBTLE FEATURE SHOULD BE ENOUGH TO WARRANT SCATTERED
SHOWERS AND STORMS AGAIN TUESDAY AFTERNOON AND EVENING. ISOLATED
SHOWERS MAY LINGER THROUGH THE NIGHT AS THE BOUNDARY STALLS OVERHEAD
AND CANNOT RULE OUT A SHOWER POPPING UP JUST ABOUT ANYWHERE.
BY WEDNESDAY...A SHARP TROUGH WILL BE DROPPING INTO THE CENTRAL
PLAINS AND GREAT LAKES REGION. HEAT AND HUMIDITY WILL AGAIN LEAD TO
ISOLATED TO SCATTERED SHOWERS AND STORMS DURING THE AFTERNOON.
HOWEVER...WE SEEM TO BE MISSING TRIGGERS...SO CONVECTION MAY NOT BE
ALL THAT WIDESPREAD. BY THURSDAY...A STRONG COLD FRONT FINALLY
PUSHES ITS WAY ACROSS EASTERN KENTUCKY WITH PROBABLY THE BEST
CHANCES FOR RAIN THIS WEEK. DRY...MUCH COOLER...AND LESS HUMID
CONDITIONS WILL THEN SURGE SOUTHWARD THURSDAY NIGHT INTO
INDEPENDENCE DAY SETTING UP A BEAUTIFUL HOLIDAY WEEKEND. THE COOLER
AND LESS HUMID CONDITIONS WILL PERSIST THROUGH SUNDAY WITH DEWPOINTS
DOWN INTO THE 50S AND POSSIBLY A FEW UPPER 40S. THIS WILL PROVIDE
COOL MORNINGS WITH LOWS WELL INTO THE 50S. HIGHS SHOULD REBOUND INTO
THE 80S EACH DAY...BUT THE LACK OF HUMIDITY WON`T MAKE IT FEEL QUITE
SO BAD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 149 AM EDT MON JUN 30 2014
SHOWERS AND THUNDERSTORMS HAVE DISSIPATED FOR THE NIGHT IT SEEMS.
HOWEVER...FOG CONTINUES TO BE A BIG WILD CARD. BASED ON THE CLOUD
COVER ACROSS THE AREA...AND THE LACK OF ANY FOG DEVELOPMENT THUS FAR
AT POINTS UPSTREAM...WAS APT TO TAKE OUT FOG WORDING AT THIS TIME.
HOWEVER...IF AN AREA EXPERIENCES SIGNIFICANT CLEARING...ESPECIALLY
TOWARDS THE PREDAWN HOURS...FOG MAY STILL BECOME A FACTOR. WILL
AMMEND AS NECESSARY. WHATEVER HAPPENS...CONDITIONS WILL GRADUALLY
IMPROVE TO VFR AFTER 12Z MONDAY...BUT MORE SCATTERED THUNDERSTORMS
ARE EXPECTED MONDAY AFTERNOON.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ABE
SHORT TERM...SBH
LONG TERM...KAS
AVIATION...JMW
AREA FORECAST DISCUSSION
NWS GRAY ME
520 AM EDT MON JUN 30 2014
.SYNOPSIS...
HIGH PRESSURE SHIFTS OFFSHORE WHICH WILL INTRODUCE MORE HUMID AIR
TO THE REGION...ALONG WITH A CHANCE FOR SCATTERED AFTERNOON
SHOWERS AND THUNDERSTORMS TODAY AND TUESDAY. A COLD FRONT WILL
TRY TO PUSH THROUGH THE AREA MID TO LATE WEEK AND WILL BE THE
FOCUS FOR THUNDERSTORM ACTIVITY...ESPECIALLY WEDNESDAY AND
THURSDAY. LOW PRESSURE WILL MOVE UP THE MID ATLANTIC COAST ON
FRIDAY...BEFORE PASSING OUT TO SEA OVER THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATE...NO MAJOR CHANGES TO THE CURRENT FORECAST.
PREVIOUS DISCUSSION...RIDGE BUILDING INTO THE AREA ATTM...WITH
MOSTLY CLEAR SKIES AND MILDER TEMPS. SFC HIGH PRES HAS SLIPPED
EWD...ALLOWING SWLY FLOW TO SET UP OVER THE AREA. THIS WILL
INCREASE BOTH HEAT AND HUMIDITY FOR TODAY. SHOULD SEE READINGS
WELL INTO THE 80S AGAIN FOR MUCH OF THE AREA...AS WELL AS A
NOTABLE UPTICK IN DEWPOINTS MAKING THINGS A BIT MORE UNCOMFORTABLE
AWAY FROM THE WATER.
DESPITE UPPER RIDGE OVERHEAD...MODEL GUIDANCE HAS BEEN CONSISTENT
IN PASSING A WEAK DISTURBANCE THRU IT THIS AFTERNOON. FORCING IS
SUBTLE...SO DO NOT ANTICIPATE MUCH MORE THAN WIDELY SCT
SHRA/TSTMS...BUT DO EXPECT THERE TO BE SOME CONVECTION IN THE
HIGHER TERRAIN TODAY. HRRR AND HI-RES CONVECTION ALLOWING MODEL
GUIDANCE ARE ON BOARD WITH THIS THOUGHT AS WELL. WE WILL HAVE THE
HEAT AND HUMIDITY AS FUEL...BUT FLOW IS QUITE WEAK WITHIN THE
RIDGE. SO ANY STORMS WILL BE SLOW MOVING...WITH LOCALLY HEAVY
RNFL BEING THE MAIN THREAT. THE MAIN CULPRIT WILL BE SLOW STORM
MOTIONS...AS PWAT VALUES ARE NOT FORECAST TO BE ABOVE NORMAL
TODAY. IN ADDITION WARM CLOUD DEPTHS ARE FAIRLY LOW...NOT
APPROACHING 10 KFT UNTIL LATE IN THE DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
TONIGHT SWLY FLOW WILL CONTINUE. MODEL GUIDANCE IS GROWING
INCREASINGLY AGGRESSIVE IN DEVELOPING COASTAL FOG/STRATUS FOR THE
OVERNIGHT. I FEEL THAT NWP MAY BE RUSHING THINGS JUST A BIT.
DEWPOINT DEPRESSIONS DON/T APPROACH ZERO UNTIL TUE NIGHT...WHICH
WOULD FAVOR BETTER FOG CHANCES THEN. WILL HAVE SOME PATCHY FOG
TONIGHT WHERE RH VALUES ARE GREATER THAN 95 PERCENT OVER THE
WATERS.
TRIPLE H KIND OF DAY IN STORE FOR MUCH OF THE AREA TUE. SW FLOW
WARM SPOTS OF SRN NH ESPECIALLY SHOULD EXCEED 90 DEGREES.
DEWPOINTS WELL INTO THE 60S WILL ADD TO THE DISCOMFORT. ALSO HAVE
LESS POP TUE THAN TODAY. CWFA SHOULD BE FIRMLY WITHIN THE UPPER
RIDGE BY THEN...WITH MODEL GUIDANCE CONSISTENT AND IN AGREEMENT
THAT LITTLE IN THE WAY OF FORCING WILL BE IN PLACE. FARTHER W IN
NY STATE CONVECTION SHOULD BE ONGOING...POSSIBLY STRONG...AND THIS
COULD SPILL OVER INTO WRN ZONES AS IT DECAYS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
WEAKENING COLD FRONT WILL CONTINUE TO BRING SOME SCATTERED PRECIP
IN THE FORM OF SHOWERS AND SCATTERED THUNDERSTORMS ACROSS
NORTHERN NEW ENGLAND. BY THURSDAY...00Z MODEL SUITE IN GOOD
AGREEMENT WITH THE SURFACE FRONT BECOMING NEARLY STATIONARY OVER
OUR REGION. THIS INCREASES POPS AND WILL MOVE INTO THE LIKELY
CATEGORY THROUGH THURSDAY NIGHT DURING THIS PACKAGE UPDATE.
ON FRIDAY...A SYSTEM WILL MOVE UP THE MID ATLANTIC REGION. LATEST
EURO MODEL RUN DEEPENS THIS LOW RAPIDLY AS IT PASSES TO OUR EAST.
LITTLE IF ANY PRECIP EXPECTED WITH THE PASSAGE OF THIS
SYSTEM...HOWEVER SWELLS WILL BE ON THE INCREASE LATE IN THE
FORECAST PERIOD...LEADING TO ENHANCED RIP RISK.
&&
.AVIATION /09Z MONDAY THROUGH FRIDAY/...
SHORT TERM...MAINLY VFR CONDITIONS TO PREVAIL THRU TUE. A WEAK
DISTURBANCE SHOULD LEAD TO WIDELY SCT SHRA/TSTMS THIS
AFTERNOON...WHICH COULD LEAD TO LOCAL MVFR OR LOWER CONDITIONS IN
THE MTNS. MODEL GUIDANCE IS FAIRLY AGGRESSIVE IN DEVELOPING
COASTAL FOG/STRATUS TONIGHT...BUT NOT CONFIDENT ENOUGH YET TO
INCLUDE IN TAFS.
LONG TERM...MAINLY VFR CONDITIONS EXPECTED. LOCAL MVFR OR LOWER
CONDITIONS POSSIBLE IN SHRA OR TSRA...ESPECIALLY THU INTO EARLY
FRI.
&&
.MARINE...
SHORT TERM...SW FLOW HAS ALREADY DEVELOPED OVER THE WATERS THIS
MORNING. COLD WATER TEMPS WILL SUPPORT A SHALLOW INVERSION WHICH
SHOULD LIMIT GUST POTENTIAL. EXPECT ANY GUSTS TO REMAIN BELOW 25
KTS. SEAS WILL GRADUALLY BUILD THRU TUE...AND A SCA FOR HAZARDOUS
SEAS MAY BE NECESSARY BY TUE.
LONG TERM...SLOWLY ADVANCING TROF WILL SET UP LONG DURATION
SOUTHWESTERLY FLOW OVER THE WATERS FOR MUCH OF THE WEEK. WIND FETCH
SHOULD EVENTUALLY ALLOW SEAS TO BUILD TO AT LEAST 5 FEET. LONG
PERIOD SWELLS MAY ARRIVE WITH AN OFFSHORE SYSTEM OVER THE WEEKEND.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
LEGRO/JC
AREA FORECAST DISCUSSION
NWS GRAY ME
258 AM EDT MON JUN 30 2014
.SYNOPSIS...
HIGH PRESSURE SHIFTS OFFSHORE WHICH WILL INTRODUCE MORE HUMID AIR
TO THE REGION...ALONG WITH A CHANCE FOR SCATTERED AFTERNOON
SHOWERS AND THUNDERSTORMS TODAY AND TUESDAY. A COLD FRONT WILL
TRY TO PUSH THROUGH THE AREA MID TO LATE WEEK AND WILL BE THE
FOCUS FOR THUNDERSTORM ACTIVITY...ESPECIALLY WEDNESDAY AND
THURSDAY. LOW PRESSURE WILL MOVE UP THE MID ATLANTIC COAST ON
FRIDAY...BEFORE PASSING OUT TO SEA OVER THE WEEKEND.
&&
.NEAR TERM /THROUGH TODAY/...
RIDGE BUILDING INTO THE AREA ATTM...WITH MOSTLY CLEAR SKIES AND
MILDER TEMPS. SFC HIGH PRES HAS SLIPPED EWD...ALLOWING SWLY FLOW
TO SET UP OVER THE AREA. THIS WILL INCREASE BOTH HEAT AND HUMIDITY
FOR TODAY. SHOULD SEE READINGS WELL INTO THE 80S AGAIN FOR MUCH OF
THE AREA...AS WELL AS A NOTABLE UPTICK IN DEWPOINTS MAKING THINGS
A BIT MORE UNCOMFORTABLE AWAY FROM THE WATER.
DESPITE UPPER RIDGE OVERHEAD...MODEL GUIDANCE HAS BEEN CONSISTENT
IN PASSING A WEAK DISTURBANCE THRU IT THIS AFTERNOON. FORCING IS
SUBTLE...SO DO NOT ANTICIPATE MUCH MORE THAN WIDELY SCT
SHRA/TSTMS...BUT DO EXPECT THERE TO BE SOME CONVECTION IN THE
HIGHER TERRAIN TODAY. HRRR AND HI-RES CONVECTION ALLOWING MODEL
GUIDANCE ARE ON BOARD WITH THIS THOUGHT AS WELL. WE WILL HAVE THE
HEAT AND HUMIDITY AS FUEL...BUT FLOW IS QUITE WEAK WITHIN THE
RIDGE. SO ANY STORMS WILL BE SLOW MOVING...WITH LOCALLY HEAVY
RNFL BEING THE MAIN THREAT. THE MAIN CULPRIT WILL BE SLOW STORM
MOTIONS...AS PWAT VALUES ARE NOT FORECAST TO BE ABOVE NORMAL
TODAY. IN ADDITION WARM CLOUD DEPTHS ARE FAIRLY LOW...NOT
APPROACHING 10 KFT UNTIL LATE IN THE DAY.
&&
.SHORT TERM /TONIGHT THROUGH 6 PM TUESDAY/...
TONIGHT SWLY FLOW WILL CONTINUE. MODEL GUIDANCE IS GROWING
INCREASINGLY AGGRESSIVE IN DEVELOPING COASTAL FOG/STRATUS FOR THE
OVERNIGHT. I FEEL THAT NWP MAY BE RUSHING THINGS JUST A BIT.
DEWPOINT DEPRESSIONS DON/T APPROACH ZERO UNTIL TUE NIGHT...WHICH
WOULD FAVOR BETTER FOG CHANCES THEN. WILL HAVE SOME PATCHY FOG
TONIGHT WHERE RH VALUES ARE GREATER THAN 95 PERCENT OVER THE
WATERS.
TRIPLE H KIND OF DAY IN STORE FOR MUCH OF THE AREA TUE. SW FLOW
WARM SPOTS OF SRN NH ESPECIALLY SHOULD EXCEED 90 DEGREES.
DEWPOINTS WELL INTO THE 60S WILL ADD TO THE DISCOMFORT. ALSO HAVE
LESS POP TUE THAN TODAY. CWFA SHOULD BE FIRMLY WITHIN THE UPPER
RIDGE BY THEN...WITH MODEL GUIDANCE CONSISTENT AND IN AGREEMENT
THAT LITTLE IN THE WAY OF FORCING WILL BE IN PLACE. FARTHER W IN
NY STATE CONVECTION SHOULD BE ONGOING...POSSIBLY STRONG...AND THIS
COULD SPILL OVER INTO WRN ZONES AS IT DECAYS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
WEAKENING COLD FRONT WILL CONTINUE TO BRING SOME SCATTERED PRECIP
IN THE FORM OF SHOWERS AND SCATTERED THUNDERSTORMS ACROSS
NORTHERN NEW ENGLAND. BY THURSDAY...00Z MODEL SUITE IN GOOD
AGREEMENT WITH THE SURFACE FRONT BECOMING NEARLY STATIONARY OVER
OUR REGION. THIS INCREASES POPS AND WILL MOVE INTO THE LIKELY
CATEGORY THROUGH THURSDAY NIGHT DURING THIS PACKAGE UPDATE.
ON FRIDAY...A SYSTEM WILL MOVE UP THE MID ATLANTIC REGION. LATEST
EURO MODEL RUN DEEPENS THIS LOW RAPIDLY AS IT PASSES TO OUR EAST.
LITTLE IF ANY PRECIP EXPECTED WITH THE PASSAGE OF THIS
SYSTEM...HOWEVER SWELLS WILL BE ON THE INCREASE LATE IN THE
FORECAST PERIOD...LEADING TO ENHANCED RIP RISK.
&&
.AVIATION /07Z MONDAY THROUGH FRIDAY/...
SHORT TERM...MAINLY VFR CONDITIONS TO PREVAIL THRU TUE. A WEAK
DISTURBANCE SHOULD LEAD TO WIDELY SCT SHRA/TSTMS THIS
AFTERNOON...WHICH COULD LEAD TO LOCAL MVFR OR LOWER CONDITIONS IN
THE MTNS. MODEL GUIDANCE IS FAIRLY AGGRESSIVE IN DEVELOPING
COASTAL FOG/STRATUS TONIGHT...BUT NOT CONFIDENT ENOUGH YET TO
INCLUDE IN TAFS.
LONG TERM...MAINLY VFR CONDITIONS EXPECTED. LOCAL MVFR OR LOWER
CONDITIONS POSSIBLE IN SHRA OR TSRA...ESPECIALLY THU INTO EARLY
FRI.
&&
.MARINE...
SHORT TERM...SW FLOW HAS ALREADY DEVELOPED OVER THE WATERS THIS
MORNING. COLD WATER TEMPS WILL SUPPORT A SHALLOW INVERSION WHICH
SHOULD LIMIT GUST POTENTIAL. EXPECT ANY GUSTS TO REMAIN BELOW 25
KTS. SEAS WILL GRADUALLY BUILD THRU TUE...AND A SCA FOR HAZARDOUS
SEAS MAY BE NECESSARY BY TUE.
LONG TERM...SLOWLY ADVANCING TROF WILL SET UP LONG DURATION
SOUTHWESTERLY FLOW OVER THE WATERS FOR MUCH OF THE WEEK. WIND FETCH
SHOULD EVENTUALLY ALLOW SEAS TO BUILD TO AT LEAST 5 FEET. LONG
PERIOD SWELLS MAY ARRIVE WITH AN OFFSHORE SYSTEM OVER THE WEEKEND.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
LEGRO/JC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
434 AM EDT MON JUN 30 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 432 AM EDT MON JUN 30 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW WSW FLOW OVER THE
UPR LKS ARND UNSEASONABLY DEEP CLOSED LO CENTERED NEAR LK WINNIPEG.
A SHRTWV THAT ROTATED ACRS NRN LK SUP EARLY THIS MRNG GENERATED SOME
SHOWERS/TS OVER THE CWA EARLIER...BUT VIGOROUS H85-7 DRY ADVCTN
DOWNSTREAM OF VERY DRY 00Z MPX RAOB /WHERE THE 00Z PWAT WAS NEAR
0.75 INCH OR ABOUT 85 PCT OF NORMAL/ AND DNVA/DEEP LYR QVECTOR DVGC
AS WELL AS NOCTURNAL COOLING HAVE ENDED THIS PCPN. HOWEVER...STEEP
LAPSE RATES SHOWN ON THE 00Z MPX RAOB HAVE ALLOWED SOME ISOLD
SHOWERS/TS TO POP UP FM TIME TO TIME OVER NCENTRAL WI AND CENTRAL
UPR MI DESPITE THE LARGER SCALE DRYING TRENDS/NOCTURNAL COOLING.
ANOTHER LARGER CLUSTER OF SHOWERS/TS IS PRESENT OVER SE WI...WHERE
THE SHRTWV IN SCENTRAL MN IS INTERACTING WITH AREA OF HIER H85-7
DEWPTS ON SE FLANK OF DRY WEDGE PUSHING INTO UPR MI. FARTHER
UPSTREAM...THERE ARE SEVERAL SHRTWVS MOVING EWD THRU THE NRN PLAINS
IN THE WLY FLOW ON THE SRN FLANK OF CLOSED LO.
MAIN FCST CONCERNS DURING THIS TIME ARE SHOWER/TS CHANCES...
ESPECIALLY LATE TODAY/TNGT WHEN A STRONGER SHRTWV ROTATING ARND THE
CLOSED LO IS FCST TO MOVE THRU THE UPR MIDWEST.
EARLY THIS MRNG/TODAY...DRY AIR SWEEPING ENEWD WITH H85-5 MEAN LYR
RH DOWN TO 30-40 PCT SHOULD ENSURE DRY WX FOR MOST OF THE CWA THIS
MRNG EVEN THOUGH SHRTWV NOW IN MN AND ASSOCIATED DPVA/SOME DEEP LYR
QVECTOR CNVGC ASSOCIATED WITH SHRTWV NOW OVER SCENTRAL MN WL SWING
ACRS THE AREA. HOWEVER...DID ALLOW FOR SOME LINGERING ISOLD
SHOWERS/TS OVER THE SE HALF OF THE CWA THRU ABOUT 15Z TO ACCOUNT FOR
THIS SHRTWV/FORCING/STEEP H85-5 LAPSE RATES UP TO 8-8.5C/KM. THESE
SHOWERS SHOULD END FOLLOWING THE EXIT OF THE SHRTWV/ARRIVAL OF
DNVA/LARGE SCALE QVECTOR DVGC. PCPN CHCS WL INCRS LATER IN THE AFTN
WITH APRCH OF STRONGER SHRTWV ROTATING ARND THE SSE FLANK OF CLOSED
LO SLOWLY DRIFTING INTO FAR NW ONTARIO. AS THE H85 WINDS BACK A BIT
WITH THE APRCH OF THIS STRONGER DISTURBANCE...MODELS INDICATE HIER
H85-7 DEWPTS/WL SURGE NEWD INTO MAINLY THE SE HALF OF THE CWA. IN
CONCERT WITH ACCOMPANYING DPVA/DEEP LYR QVECTOR CNVGC ASSOCIATED
WITH THE SHRTWV AND H4-2 DVGC IN RRQ OF 100KT H3 JET MAX MOVING THRU
NW LK SUP...WL CONT TO SHOW INCRSG POPS OVER MAINLY THE SCENTRAL
LATE IN THE DAY. CONSIDERING THE RATHER IMPRESSIVE DYNAMICS/MSTR
RETURN THAT IS FCST TO LIFT PWAT CLOSE TO 2 INCHES OVER THE SCENTRAL
BY 00Z /175 PCT OF NORMAL/...PREFER THE HIER POPS A BIT FARTHER TO
THE W/HIER QPF SHOWN BY THE 00Z NAM/REGIONAL CNDN MODEL. AS FOR
TEMPS...EXPECT THE HIEST TEMPS OVER THE INTERIOR W HALF WHERE THERE
WL BE MORE SUNSHINE THRU MUCH OF THE DAY UNTIL CLDS BEGIN TO INCRS
THIS AFTN. DEEP MIXING TO H75 WL SUPPORT HI TEMPS APRCHG 85 AND
ALLOW FOR GUSTY WINDS TO MIX TO THE SFC.
TNGT...VIGOROUS DYNAMICS/MSTR RETURN ARE FCST TO IMPACT MAINLY THE
SE 2/3 OF THE CWA IN THE 00Z-06Z PERIOD AND JUSTIFY SOME CATEGORICAL
POPS OVER THE SE CWA IN THE EVNG BEFORE DNVA/DEEP LYR QVECTOR
DVGC/MID LVL DRYING RETURNS IN THE WAKE OF SHRTWV PASSAGE.
CONSIDERING THE UNSEASONABLY STRONG UPR DYNAMICS...THERE IS SOME
CONCERN AS TO WHETHER ANY OF THE TS COULD BE STRONG TO SEVERE. THE
LATEST SPC CONVECTIVE OUTLOOK SHOWS UPR MI JUST N OF THE THE SLGT
RISK AREA. THE BEST CHC FOR SOME SVR TS WOULD BE WHEN THE DYNAMICS
ARRIVE LATE THIS AFTN WHEN LLVL LAPSE RATES ARE STILL STEEP/DCAPE
WOULD BE HIER FOLLOWING THE DAYTIME HEATING AND WHEN THE LLVL
ENVIRONMENTAL WINDS ARE A UNIDIRECTIONAL SW AND AS HI AS 50 KTS AT
H7. GUSTY WINDS WOULD BE THE MAIN THREAT. DURING THIS EVNG...HEAVY
RA LOOKS TO BE THE MAIN CONCERN WITH RATHER HI FRZG LVL NEAR 13K FT/
MARGINAL MID LVL LAPSE RATES DESPITE SOME FAIRLY STRONG WINDS ALF.
ARRVIAL OF SOME COOLER AIR/MID LVL DRYING WL ALLOW TEMPS OVER THE W
TO FALL INTO THE 50S TNGT. SOME LOCALLY DENSE FOG COULD OCCUR OVER
THE E LATE WITH SOME MID LVL DRYING FOLLOWING DEPARTING SHRTWV OVER
THE RA MOISTENED LLVLS WITH SW FLOW OFF LK MI.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 328 AM EDT MON JUN 30 2014
A LARGE UPPER TROUGH WILL STILL BE IN PLACE OVER ONTARIO AND THE
NORTH CENTRAL CONUS ON TUESDAY MORNING. A SHORTWAVE ROTATING AROUND
THIS UPPER TROUGH WILL SHIFT THROUGH THE UPPER GREAT LAKES REGION
TONIGHT AND BE PULLING NORTHEAST OUT OF THE AREA. EXPECT ANY
CONVECTION ASSOCIATED WITH THIS SHORTWAVE AND LOW CENTER TO QUICKLY
BE MOVING NORTHEAST THROUGH ONTARIO ON TUESDAY MORNING. A COLD FRONT
STRETCHING SOUTHEAST FROM THE LOW IN ONTARIO WILL TRACK ACROSS THE
UPPER GREAT LAKES REGION TUESDAY AFTERNOON AND NIGHT...LEADING TO
ANOTHER OPPORTUNITY FOR SHOWERS AND MAYBE A FEW THUNDERSTORMS.
EXPECT THE BULK OF THE SHOWER COVERAGE TO DEVELOP OVER THE LAND
AREAS AROUND NOON ON TUESDAY AND SPREAD IN COVERAGE THROUGH THE
AFTERNOON HOURS. THINK THE BEST COVERAGE WILL BE OVER THE
EAST/SOUTHEAST HALF OF UPPER MICHIGAN...ESPECIALLY
ALGER/SCHOOLCRAFT/LUCE COUNTIES WHERE THERE WILL BE SOME HELP FROM
CONVERGENCE OFF LAKE SUPERIOR. WILL CONTINUE TO SHOW HIGH CHANCE OR
LOW END LIKELY VALUES IN THOSE AREAS. FARTHER TO THE WEST...COVERAGE
IS A LITTLE MORE UNCERTAIN DUE TO INDICATIONS OF A WEAK SURFACE
TROUGH SHIFTING THROUGH DURING THE DAY. THIS WILL SHIFT WINDS A
LITTLE MORE WESTERLY (OR EVEN NORTHWESTERLY) AND BRING IN MORE
STABLE AIR FROM LAKE SUPERIOR. THINK THAT WILL KEEP MUCH OF THE
KEWEENAW PENINSULA DRY AND WILL HOLD ONTO SLIGHT OR LOW CHANCES FOR
THE REST OF THE WESTERN HALF OF UPPER MICHIGAN. MID LEVEL LAPSE
RATES ARE ONLY AROUND 5-6 C/KM...HELPING TO LIMIT THUNDER POTENTIAL
AND KEEPING ML CAPES GENERALLY BELOW 200 J/KG. THUS...WILL CONTINUE
TO KEEP THUNDER CHANCES CAPPED AT SLIGHT CHANCES (ALTHOUGH WITH THE
LATEST TRENDS THAT MAY BE GENEROUS). IN ADDITION...IT WILL BE BREEZY
OVER THE KEWEENAW ON TUESDAY. A TIGHT PRESSURE GRADIENT AND STRONGER
WINDS ALOFT (950-925MB WINDS OF 30-35KTS) WILL LEAD TO GUSTS
AROUND 30KTS OVER THE HIGHER TERRAIN LOCATIONS...ALTHOUGH THE MARINE
LAYER MAY TRY TO HOLD SOME OF THE WINDS AT BAY NEAR THE SHORELINE.
AS THE COLD FRONT SHIFTS THROUGH LATE TUESDAY AFTERNOON AND
EVENING...A PERIOD OF ABUNDANT LOW LEVEL MOISTURE AND NORTHWEST FLOW
WILL DEVELOP OVER THE AREA AND LINGER INTO THE OVERNIGHT HOURS. WITH
THE FAVORABLE UPSLOPE FLOW...THINK THE BEST OPPORTUNITY FOR SHOWERS
WILL BE IN THE NORTHWEST WIND FAVORED LOCATIONS IN THE NW HALF OF
UPPER MICHIGAN. DON/T EXPECT THE AMOUNTS TO BE ANYTHING TOO
IMPRESSIVE...A FEW HUNDREDTHS...BUT WILL SHOW CHANCE POPS IN THE
HIGHER TERRAIN FROM GOGEBIC COUNTY THROUGH THE KEWEENAW AND ALSO
HIGHER TERRAIN OF BARAGA AND WESTERN MARQUETTE COUNTY. EXPECT
THESE SHOWERS TO CUT OUT FAIRLY QUICKLY AROUND DAYBREAK...AS MUCH
DRIER AIR SURGES SOUTHEAST INTO THE AREA. THIS WILL LEAD TO
DECREASING CLOUDS FROM NW TO SE ON WEDNESDAY MORNING AND EXPECT THE
AFTERNOON TO BE SUNNY FOR ALL BUT THE SOUTH CENTRAL (WHERE THERE
COULD BE SOME LINGERING DIURNAL CU). WITH THE NORTHWEST WINDS ON
WEDNESDAY...THERE MAY BE AN ELEVATED SWIM RISK FOR ALGER COUNTY
BEACHES. BUT WITH TEMPERATURES STRUGGLING TO GET OUT OF THE
50S...THE AMOUNT OF SWIMMERS WILL BE LIMITED IN THE LOW 40 DEGREE
WATER TEMPERATURES. ELSEWHERE...HIGHS WILL BE WELL BELOW NORMAL AND
IN THE 60S.
HIGH PRESSURE DEVELOPING OVER THE NORTHERN/CENTRAL PLAINS ON
WEDNESDAY WILL SHIFT A RIDGE EAST OVER THE UPPER GREAT LAKES REGION
WEDNESDAY AFTERNOON AND NIGHT. THIS RIDGE WILL STAY IN PLACE
THROUGH THE REST OF THE WORK WEEK...AS THE HIGH SHIFTS THROUGH THE
GREAT LAKES REGION AND THEN INTO THE MID ATLANTIC STATES ON
SATURDAY. THERE SHOULD BE COOLER AND GENERALLY CLEAR CONDITIONS
DURING THIS PERIOD...ALTHOUGH A WEAK SHORTWAVE MAY LEAD TO SOME
CLOUDS ON THURSDAY. EXPECT THE LOWEST LOW TEMPERATURES ON WEDNESDAY
NIGHT...WITH GOOD RADIATIONAL COOLING UNDER CLEAR SKIES...LIGHT
WINDS...AND PWATS AROUND 40 PERCENT OF NORMAL. LIKED THE TREND
SHOWN BY THE PREVIOUS SHIFT (TOWARDS THE BETTER PERFORMING MEX
GUIDANCE ON RADIATIONAL COOLING NIGHTS) AND WILL CONTINUE THAT IDEA.
THAT GIVES LOWS FOR SOME OF THE COLD SPOTS OUT WEST IN THE LOWER 40S
AND UPPER 30S. SHOULD SEE GRADUALLY WARMING HIGHS/LOWS FOR THE REST
OF THE WORK WEEK AND THE 4TH OF JULY STILL LOOKS TO BE A GREAT DAY
FOR OUTDOOR ACTIVITIES. HIGHS WILL BE CLOSE TO NORMAL (70S) UNDER
MOSTLY SUNNY SKIES AND GENERALLY LIGHT WINDS.
HEADING INTO THE WEEKEND...MODELS ARE CONTINUING TO STRUGGLE WITH A
POTENTIAL SHORTWAVE MOVING THROUGH THE NEARLY ZONAL FLOW. THAT IS
TO BE EXPECTED AND LEADS TO LOW CONFIDENCE FOR FRIDAY NIGHT INTO
SATURDAY. WILL SHOW GENERALLY SLIGHT CHANCES INCREASING OVER THE
WESTERN HALF OF THE CWA DURING THIS PERIOD...WITH THE DRY AIR FROM
THE HIGH KEEPING THE EAST DRY. THE INCREASING SOUTHERLY FLOW OVER
THE AREA THIS WEEKEND WITH THE HIGH SHIFTING TO THE SOUTHEAST WILL
LEAD TO AN INCREASE IN TEMPS TO MORE NORMAL OR SLIGHTLY ABOVE
NORMAL VALUES AND ALSO PRODUCE MORE HUMID CONDITIONS. SUNDAY VARIES
TOO...SO WILL GO WITH A CONSENSUS OF THE MODELS AND LEADS TO POPS
SIMILAR TO CLIMO.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 124 AM EDT MON JUN 30 2014
EXPECT VFR CEILINGS AND VIS THROUGH THE PERIOD AT ALL SITES. THE MAIN
CONCERN WILL BE POSSIBLE CONVECTION DEVELOPING OVER CENTRAL UPR MI
LATE MON AFTERNOON AND EVENING AND WHETHER IT WILL AFFECT KSAW.
INCLUDED LLWS AT KCMX OVERNIGHT AS WINDS DECOUPLE SOMEWHAT NEAR THE
SFC AND LOW-LVL JET MAX MOVES OVERHEAD. ANOTHER ROUND OF STRONGER S
WINDS OF 20-30KTS WILL BE POSSIBLE MONDAY...STARTING JUST AFTER 12Z
AND CONTINUING THROUGH THE DAY. WILL INCLUDE SHRA IN KSAW TAF AFT
00Z TUE WITH VCTS FOR POSSIBLE CONVECTION DEVELOPING AHEAD OF UPPER
DISTURBANCE MOVING UP FROM THE CENTRAL PLAINS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 328 AM EDT MON JUN 30 2014
A STRONG LOW PRESSURE SYSTEM NEAR LAKE WINNIPEG WILL GRADUALLY
SHIFT EAST ACROSS ONTARIO TODAY AND TONIGHT...BEFORE MERGING WITH A
SECONDARY LOW NEAR JAMES BAY ON TUESDAY. EXPECT SOUTH TO
SOUTHWESTERLY WINDS DURING THIS PERIOD...BUT THE MARINE LAYER
SHOULD KEEP WINDS BELOW 25KTS. WARM AND HUMID AIR MOVING OVER LAKE
SUPERIOR WILL CONTINUE TO BRING THE OPPORTUNITY FOR FOG...WITH THE
BEST CHANCE OF LOCALLY DENSE FOG OVER THE NORTHERN HALF OF LAKE
SUPERIOR. A COLD FRONT WILL MOVE SOUTHEAST ACROSS LAKE SUPERIOR ON
TUESDAY NIGHT AND SHIFT WINDS TO THE WEST-NORTHWEST. THIS WILL ALSO
BRING AN END TO THE FOG POTENTIAL AS COOLER AND DRIER AIR MOVES
INTO THE AREA. A HIGH PRESSURE RIDGE WILL DEVELOP OVER LAKE
SUPERIOR ON WEDNESDAY AFTERNOON AND REMAIN THROUGH SATURDAY AS THE
PARENT HIGH SHIFTS EAST FROM THE PLAINS STATES TO THE MID ATLANTIC
STATES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...VOSS
MARINE...SRF
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
1141 PM CDT Sun Jun 29 2014
.UPDATE...
Issued at 937 PM CDT SUN JUN 29 2014
00Z/7pm CDT upper air observation at KSGF shows some warming in
the 800-700mb with ongoing warm air advection in that layer.
Progged soundings for the same time (00z), while overdoing the
cap/warming, have latched onto the idea of fairly poor lapse rates
in that layer. In the near term, looking for continued quiet
weather.
Later tonight....New 00z NAM (and the 18z) is just doing a terrible job
in the near term with convection. HRRR and ARW (among some others)
seem to have a good general handle with ongoing convection over NE
Kansas/NW Missouri. Could see convection develop southeast with
convective outflow interacting with the nocturnal low level jet
overnight. Best chances for precip would be over the northern
cwfa, but overall have cut back on pops and severe weather chances
tonight (still limited). Will continue to watch trends unfold and
make adjustments as needed.
&&
.SHORT TERM...(This Evening through Monday)
Issued at 249 PM CDT SUN JUN 29 2014
The active weather pattern will continue through Monday...and
beyond. As we go through early this evening, we are expecting
pop-up type convection over the eastern Ozarks to slowly wane.
Meanwhile, confidence is beginning to increase that we may have to
deal with another line of storms from later this evening into the
overnight period. We will be closely watching for convective
initiation across northeastern Kansas/northern Missouri this
afternoon. Cold pools from what will initially be cellular
convection should quickly conglomerate given very high low level
theta-e differentials. Once conglomeration occurs and a low level
jet strengthens this evening, any developing MCS should take a
hard turn to the south-southeast and become forward-propagating
in nature. It will certainly have damaging wind potential given
extreme instability and high theta-e differentials (especially
north of I-44).
Timing remains a question as it will be highly dependent on
if/when initiation occurs across the I-70 corridor. It could
come into west-central Missouri as early as 7 to 8 PM...but may
also hold off until late evening. Regardless, we will be ramping
up PoPs tonight and hitting the wind potential in the Hazardous
Weather Outlook products. We will also have to watch for
regenerative growth later tonight if the convective outflow stalls
and interacts with the low level jet.
It should be noted that there are also multiple convection-
allowing models that do not generate an MCS at all to our north.
If the MCS does not pan out, we would be left with isolated to
widely scattered convective potential as a low level jet veers
over the region later tonight. The bottom line here...we will be
keeping our eyes peeled on the I-70 corridor into this
evening...making forecast adjustments if necessary.
Any leftover activity should quickly diminish Monday morning with
the majority of the day looking dry, hot, and humid. Highs will
have no problem warming into the lower 90s with heat indices in
the 98 to 104 degree range. It will also be a windy day with brisk
and gusty south to southwest surface winds. By late in the
afternoon, we are expecting another MCS to develop up towards I-70
along an advancing cold front. It is possible that this activity
approaches the Truman and Lake of the Ozarks region by late
afternoon. Once again, this activity will have wind damage
potential.
.LONG TERM...(Monday Night through Sunday)
Issued at 249 PM CDT SUN JUN 29 2014
That cold front will then seep south into the area Monday night
and Tuesday continuing the threat for showers and thunderstorms.
That front will then get nudge into northern Arkansas from Tuesday
night into Wednesday morning. More showers and thunderstorms are
probable, especially across extreme southeastern Kansas and
southern Missouri during this time period. A threat for strong to
severe storms will remain...with perhaps an increasing threat for
flooding due to a cumulative effect from multiple rounds of
thunderstorms. We considered a Flash Flood Watch, but would like
to get a better feel for the track of MCSs before pulling the
trigger.
The threat for storms should finally push south of the Missouri
Ozarks by Wednesday night with dry and cooler weather currently
anticipated from Thursday through Saturday. High temperatures will
be pleasant with highs in the upper 70s to lower 80s and lows in
the lower 60s.
&&
.AVIATION...(For the 06Z TAFS through 06Z Monday Night)
Issued at 1125 PM CDT SUN JUN 29 2014
For the KSGF/KJLN/KBBG tafs: Some low stratus is occurring east
and northeast of the taf sites along and south of I-44 about as
far west as Lebanon, Ava, and West Plains. It doesn`t look like
given the progged winds that this stratus will move/advect into
the taf sites, but will watch trends. High cirrus deck from storms
well north of the area will continue to to shift into the area.
Progged soundings dry out quite a bit for much of the day Monday
along with some increased capping, so will likely have vfr
conditions depicted at all taf sites. A cold front will reach an
area just north of KSGF and KJLN by the end of the taf period
with a somewhat increased chance for showers/thunderstorms, but
don`t think expected rain coverage warrants a mention in the tafs
at this point.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
UPDATE...DSA
SHORT TERM...Schaumann
LONG TERM...Schaumann
AVIATION...DSA
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1140 PM CDT Sun Jun 29 2014
.UPDATE:
Issued at 948 PM CDT Sun Jun 29 2014
Scattered thunderstorms over north central and northwest Missouri
are occurring in an axis of 925-850mb moisture convergence that
shows up well in latest run of the RAP. This forcing will shift
eastward the next few hours as the low level winds veer. Current
motion of the supercell over north central Missouri has it moving
into the the northwestern CWA around midnight. HRRR composite
reflectivity still shows that current activity will move east into
central and northeast Missouri and west central Illinois through
09Z before diminishing. Have maintained likely PoPs during the late
evening and overnight hours in these areas with chance PoPs
elsewhere. Rest of forecast still looks on track.
Britt
&&
.SHORT TERM: (Through Late Tonight)
Issued at 357 PM CDT Sun Jun 29 2014
An area of convection was moving through southeastern MO, clipping
the extreme southern portion of the forecast area this afternoon,
with more scattered activity mainly between COU and STL. This
convection was mainly due to diurnal heating and destabilization and
should dissipate by sunset. More organized convection is expected
to develop this evening and move through the northern and western
portion of our forecast area late this evening and overnight.
Convection is expected to develop across southeastern Nebraska,
northeast Kansas and southwest Iowa late this afternoon and early
this evening ahead of a vort max or MCV moving eastward into
northeast KS, and in an area of low level warm air advection on the
nose of a s-swly low level jet. Some of this convection should move
southeastward into central MO late this evening and into the
overnight hours with additional convection developing or moving into
northeast MO and west central IL during this time period as well.
The atmosphere will be very unstable and there will be adequate
low-mid level wind shear that some of the storms across northeast MO
could be severe with damaging winds being the most likely hazard.
Most of the convection should remain north and west of STL. Low
temperatures tonight should be a little warmer than the previous
night due to slightly stronger surface winds and slightly higher
surface dew points.
GKS
.LONG TERM: (Monday through Next Sunday)
Issued at 357 PM CDT Sun Jun 29 2014
It appears that going forecasts have a fairly good handle on
convective/precip trends heading into the new work week, which
remains the primary short-term forecast concern.
Although the exact evolution of tonight`s activity is still a bit
uncertain, based on model consensus and climatology any convection
that is generated during the overnight hours should be exiting
southeast sections of the CWA early Monday morning. Once this
occurs, there should be a fairly prolonged period of dry weather as
very warm mid-level temps cap any additional development until the
approach of the cold front towards northwest sections of our CWA
late in the day. It certainly appears that the last day of June is
going to be a steamy one over most of the FA, and even taking into
account mixing it appears that dewpoints will hold in the low-mid
70s over most of the region. Don`t believe that the low clouds of
today will be hanging around tomorrow, especially in the afternoon,
so with at least partial sunshine and 850mb temps of 20-22C progged
over the region highs should be topping out in the low-mid 90s.
This combo of temperatures and dewpoints will push the afternoon
heat index to around 105 degrees in the STL metro, so will be going
out with a heat advisory for this area from 17z Monday-01z Tuesday
(Monday afternoon and early evening).
Obviously this AMS will be extremely unstable, and as the
aforementioned cold front and associated shortwave interact with it
during the afternoon a large area of strong to severe convection
will develop from IA and possibly extending into northwest and/or
north central MO. Some of these storms may threaten northwest
sections of the FA by late in the afternoon, but the primary threat
in our CWA will likely be Monday evening. There will certainly be
some severe weather potential in northern sections of our CWA with
this activity due to the extreme instability (even some of the more
conservative output suggests MUCAPES of 3000-4000 j/kg) and 30-50kts
of bulk shear> However, all of the operational models suggest
intensity and coverage of convection should wane as cold front
pushes into southern sections of the CWA later in the night, and
this appears reasonable with primary shortwave energy tracking
almost due east along with weakening frontal convergence and
instability. Again, this trend is already in going forecast and
looks good.
Synoptic scale models are still suggesting several additional
shortwaves will migrate through the region Tuesday-Tuesday night as
upper trof deepens from the Great Lakes into the Mississippi
Valley. These dynamics should interact with moisture near and
north of slowing cold front to maintain some shower and thunderstorm
threat. Best chances should be over the southern half of the CWA
on Tuesday night, but given the baroclinicity and potential
iscentropic lift have continued some very low slight chance PoPs as
far north as UIN. The threat of precip with the last shortwave
should wind down on Wednesday.
Latest medium range guidance still suggests some atypically cool and
low humidity air will blanket the area heading into the 4th of July
holiday. However, temperatures and humidity levels should begin to
rebound to more normal summertime levels during the weekend as trof
works east and ridge over the Rockies rebounds into the central
CONUS. A threat of showers and thunderstorms will return during
the latter half of the weekend as a shortwave on east side of
ridge clips the area.
Truett
&&
.AVIATION: (For the 06z TAFs through 06z Monday Night)
Issued at 1129 PM CDT Sun Jun 29 2014
Ongoing TSRA over n cntl MO will continue to move newd. Can not
rule out a storm impacting UIN in an hour or two, but chances are
diminishing. Otherwise, MVFR cigs have already moved back into
SUS/CPS and shud remain in place thru the night. Cigs are expected
to begin to lift after sunrise. COU/UIN shud see MVFR cigs develop
shortly after sunrise. Cigs will gradually lift and sct by mid day
with strong sly to sswly winds gusting to 25 kits...perhaps
greater late in the afternoon. Latest guidance suggests a line of
TSRA dropping swd impacting UIN and COU late in the TAF period.
Specifics for KSTL: MVFR cigs have moved back into the region and
shud remain thru the night and begin to lift late in the morning.
Sswly winds shud increase during the late morning thru the
afternoon with gusts to around 25 kts, poss higher. These gusts
shud diminish during the evening hours.
Tilly
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...HEAT ADVISORY from Noon to 8 PM CDT Monday FOR St. Charles MO-
St. Louis City MO-St. Louis MO.
IL...HEAT ADVISORY from Noon to 8 PM CDT Monday FOR Madison IL-St.
Clair IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1213 AM CDT MON JUN 30 2014
.SYNOPSIS...
ISSUED AT 251 PM CDT SUN JUN 29 2014
WEATHER CONDITIONS WILL CLOSELY MONITORED FOR SEVERE
STORM DEVELOPMENT OVERNIGHT. A COLD FRONT WILL MOVE THROUGH LATE
TONIGHT AND MONDAY MORNING STABILIZING THE ATMOSPHERE. A
REINFORCING COLD FRONT ARRIVES TUESDAY. COOL WEATHER CONTINUES
THROUGH WEDNESDAY FOLLOWED BY A WARMING TREND THURSDAY THROUGH
SUNDAY WITH NEAR OR SLIGHTLY ABOVE NORMAL TEMPERATURES AND
GENERALLY ISOLATED RAIN CHANCES.
&&
.UPDATE...
ISSUED AT 1056 PM CDT SUN JUN 29 2014
UPDATED FORECAST TO ACCOUNT FOR ECHOES MOVING INTO SOUTHWEST
NEBRASKA FROM NORTHEAST COLORADO. LOW LEVEL JET TO KICK UP AGAIN
TONIGHT AND EXPAND THUNDERSTORMS FROM NORTHERN KANSAS NORTH INTO
NORTH CENTRAL NEBRASKA SIMILAR TO LAST NIGHT. HAVE BEEN A BIT
LIBERAL WITH NORTHWARD PROGRESSION.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 251 PM CDT SUN JUN 29 2014
TONIGHT AND TOMORROW. CONVECTION CHANCES TO HEADLINE
THE SHORT TERM DISCUSSION. KEEPING SLIGHT CHANCE TO LOW END CHANCE
OF POPS IN THE FORECAST FOR LOCATIONS GENERALLY EAST OF HIGHWAY 83
THIS AFTERNOON AND EVENING. UNDER MOSTLY CLEAR SKIES THE ATMOSPHERE
HAS UNDERGONE STRONG DESTABILIZATION...WITH THE OPERATIONAL RAP AND
LATEST LAPS DATA GENERATING UPWARDS OF 3000 J/KG OF MUCAPE ACROSS
SOUTHEASTERN PORTIONS OF THE FORECAST AREA. WITH OPTIMAL DEEP SHEAR
IN PLACE...STORMS...SOME OF WHICH MAY BE SEVERE WITH HAIL AND
DAMAGING WIND BEING THE PRIMARY THREATS...ARE ANTICIPATED TO FORM.
A SIGNIFICANT -10 TO -30C CONTRIBUTION TO THE CAPE /CLOSING ON A
1000 J/KG/ WOULD SUPPORT SOME LARGE HAIL. THE LATEST NEAR TERM
CONVECTION ALLOWING MODELS GENERATES THE PROJECTED ACTIVITY WELL TO
THE EAST OF THE CWA...BUT RECENT SATELLITE OBS INDICATE OTHERWISE
WITH THE FORMATION OF A AGITATED CU FIELD ACROSS CUSTER COUNTY.
WILL CONTINUE TO MONITOR THE CONVECTIVE TRENDS. WEST OF THIS
AREA...INSTABILITY AND AVAILABLE CAPE DECREASES RAPIDLY...ONLY
ISOLATED GENERAL STORMS WOULD BE POSSIBLE.
FOR THE OVERNIGHT...INCREASINGLY RICH THETA-E BUILDS BACK TO THE
NORTHWEST WITH THE STRENGTHENING OF A LLJ. THE THREAT OF STORMS
WILL REMAIN THROUGH THE OVERNIGHT FOR LOCATIONS MAINLY EAST OF
HIGHWAY 83. OVERNIGHT LOWS WILL RANGE FROM THE 50S ACROSS THE
NORTHWEST...TO MID 60S ACROSS THE EAST.
SLIGHTLY COOLER FOR MONDAY WITH A FRONTAL PASSAGE EARLY. HIGHS IN
THE 70S TO LOWER 80S SHOULD PREVAIL. LINGERING POST FRONTAL STORMS
ARE POSSIBLE EARLY MONDAY ACROSS NORTH CENTRAL NEBRASKA...BUT BY
AFTERNOON THIS ACTIVITY SHOULD BE OFF TO THE EAST.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 251 PM CDT SUN JUN 29 2014
MONDAY NIGHT THROUGH WEDNESDAY...A REINFORCING CANADIAN COLD FRONT
WILL MOVE THROUGH TUESDAY. THE PRECEDING PACIFIC COLD FRONT SUPPORTS
LOWS IN THE 50S TUESDAY MORNING. LOWS WEDNESDAY MORNING ARE ABOUT 5F
COLDER FOR LOWS IN THE LOWER 50S. THERE IS POTENTIAL FOR COOLER LOWS
WEDNESDAY MORNING BUT THE MODELS SHOW 850MB-700MB CLOUDS WRAPPING
SOUTH AROUND A DEPARTING UPPER LEVEL LOW ACROSS ONTARIO.
RAIN CHANCES CONTINUE IN PLACE TUESDAY WITH COLD AIR MOVING IN
ALOFT. H700MB TEMPERATURES FALL TO 6C TO 10C AND HIGHS RISE TO ONLY
70 NORTH. NORTHWEST WINDS INCREASE TO 20 TO 30 MPH TUESDAY WITH
HIGH PRESSURE BUILDING SOUTH ALSO.
THE COLD AIR ALOFT MOVES OFF EAST WEDNESDAY FOR HIGHS 75 TO 80 WITH
NEARLY FULL SUN AND LIGHT WINDS...A COMPLETE REVERSE OF TUESDAYS
WIND...CLOUDS...SHOWERS AND COOLER TEMPERATURES.
WEDNESDAY NIGHT THROUGH SUNDAY...THE MODELS ARE IN VERY GOOD
AGREEMENT PRODUCING 20 TO 25 MPH SLY RETURN FLOW THURSDAY AND
FRIDAY. THE WARMING TREND IS SLOWER GIVEN THE STRONGER PUSH OF
CANADIAN AIR TUESDAY FOR HIGHS IN THE 80S TO AROUND 90 THURSDAY
THROUGH SUNDAY. REGARDLESS...INSTABILITY INCREASES IN THE
ECM...GFS AND GEM MODELS THURSDAY THROUGH SATURDAY. IF WINDS ALOFT
CAN REMAIN STRONG AS SHOWN THE GEM AND GFS SOLNS THEN ISOLATED
THUNDERSTORMS COULD DEVELOP IN A NORTHWEST FLOW REGIME THURSDAY
AND BEYOND. THE ECM BUILDS THE UPPER LEVEL RIDGE STRONGLY
PRODUCING WEAK WINDS ALOFT. THE FORECAST FOLLOWS THE GFS AND
INCLUDES ISOLATED POPS WHICH FITS THE CLASSIC JULY NORTHWEST FLOW
CLIMATOLOGY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1212 AM CDT MON JUN 30 2014
SOME SCATTERED RAINSHOWERS OVER SOUTHWEST NEBRASKA WILL INCREASE AS
THE LOW LEVEL SOUTHERLY JET INCREASES THROUGH THE EARLY MORNING
HOURS. NOT REAL CONFIDENT WITH THE NORTHERN PROGRESSION OF THE
SYSTEM AND HAVE JUST INCLUDED A TEMPO GROUP -TSRA FOR THE KLBF TAF
SITE. THROUGH THE MORNING THUNDERSTORMS SHOULD BECOME MORE
WIDESPREAD AND MOVE TO THE NORTHEAST INTO NORTH CENTRAL NEBRASKA
EAST OF A LINE FROM KLBF TO KVTN. VFR CONDITIONS EXPECTED AT TAF
SITES BUT IN AREAS OF THUNDERSTORMS MVFR CIGS AND VISIBILITIES ARE
EXPECTED. STORMS SHOULD MOVE EAST THROUGH THE MORNING. NORTHERLY
WINDS OVER WESTERN NEBRASKA WILL INCREASE TO 10 TO 20 MPH WITH GUSTS
TO AROUND 30 MPH THROUGH THE DAY ON MONDAY UNDER MAINLY CLEAR SKIES.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...POWER
SYNOPSIS...CDC
SHORT TERM...JACOBS
LONG TERM...CDC
AVIATION...POWER
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1211 AM CDT MON JUN 30 2014
.UPDATE...
ISSUED AT 928 PM CDT SUN JUN 29 2014
INCREASED POPS ACROSS FAR NORTHERN KANSAS AND MUCH OF SOUTH
CENTRAL NEBRASKA...ESPECIALLY IN THE TRI CITIES AREA. FORECAST
MODELS CONTINUE TO INDICATE A WELL PLACED LOW LEVEL JET WITH
CONVERGENCE ALONG THE NOSE OF THIS JET CENTERED OVER OUR FORECAST
AREA AFTER MIDNIGHT. THE HRRR IS THE FURTHEREST SOUTH WITH THE
CONVECTION FOCUSING THE HEAVIEST CONVECTION OVER NORTH CENTRAL
KANSAS AND THE FAR SOUTHERN TIER OF NEBRASKA COUNTIES AFTER
MIDNIGHT. THE NAM...RAP...AND SREF FOCUS THE CONVECTION A LITTLE
FURTHER NORTH CENTERING THE HIGHEST POPS OVER THE TRI CITIES
BETWEEN 3 AM AND 7 AM. WILL FOLLOW THE CONSENSUS GUIDANCE WITH THE
HIGHEST POPS ACROSS SOUTH CENTRAL NEBRASKA. THUNDERSTORMS SHOULD
BEGIN TO FORM ANYTIME AFTER 10 PM ACROSS SOUTHWEST NEBRASKA NEAR
THE KANSAS STATE LINE AND THEN TRACK EAST POSSIBLY BUILDING SOUTH
INTO NORTHERN KANSAS. SOUNDINGS INDICATE SIGNIFICANT ELEVATED
INSTABILITY WITH OVER 3000 J/KG OF CAPE FROM AN ELEVATED PARCEL.
THE COMBINATION OF HIGH INSTABILITY AND DEEP LAYER WIND SHEAR TO
NEAR 50 KTS WILL CERTAINLY SET THE STAGE FOR THE POSSIBILITY OF A
LATE NIGHT SEVERE WEATHER EVENT. WOULD NOT BE SURPRISED TO SEE
SOME GOLF BALL SIZED OR EVEN LARGER HAIL REPORTS DURING THE
MIDDLE OF THE OVERNIGHT PERIOD.
UPDATE ISSUED AT 631 PM CDT SUN JUN 29 2014
DESPITE THE HIGH INSTABILITY AND STRONG VERTICAL WIND SHEAR...IT
APPEARS THAT THE LACK OF GOOD FORCING HAS BEEN WINNING OUT THIS
EVENING AND THUS WE HAVE SEEN NO CONVECTIVE DEVELOPMENT ACROSS OUR
AREA. THE ONLY THUNDERSTORMS HAVE BEEN EAST OF OUR FORECAST AREA
WHERE THE FORCING IS BETTER. WE ARE COLLABORATING WITH THE SPC ON
TRIMMING SOME OF THE WESTERN COUNTIES FROM OUR TORNADO WATCH. IT
SEEMS LIKELY AT THIS POINT IN TIME THAT MOST OF OUR TORNADO WATCH
WILL BE CANCELED EARLY UNLESS WE START TO SEE SOMETHING DEVELOP
SOON.
WE WILL SEE BETTER FORCING BY LATE EVENING ASSOCIATED WITH THE
INCREASING LOW LEVEL JET WHICH WILL NOSE INTO OUR FORECAST AREA IN
NEAR TEXT BOOK FASHION FOR AN INCREASING THREAT OF ELEVATED
STRONG TO SEVERE THUNDERSTORMS PRIMARILY AFTER 10 PM. WOULD NOT BE
SURPRISED IF A SEVERE THUNDERSTORM WATCH ENDS UP BEING NEEDED
AS WE HEAD TOWARDS MIDNIGHT OR INTO THE PRE DAWN HOURS OF EARLY
MONDAY MORNING.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 332 PM CDT SUN JUN 29 2014
MAIN FORECAST CONCERN WILL BE THUNDERSTORMS THROUGH MONDAY MORNING.
CLOUDS FROM THE MORNING CONVECTION HAVE MAINLY CLEARED OUT OF THE
FORECAST AREA DURING THE EARLY AFTERNOON. A FEW CUMULUS HAVE
STARTED TO DEVELOP BUT NONE OF THEM HAVE MUCH VERTICAL EXTENT
AN UPPER LEVEL WAVE WILL BE MOVING THROUGH THE FORECAST AREA THIS
AFTERNOON AND INTO THE EVENING HOURS. THUNDERSTORMS ARE EXPECTED TO
DEVELOP THIS AFTERNOON IN THE VICINITY OF THE UPPER LEVEL WAVE.
THERE IS OVER 4000 J/KG MU CAPE THIS AFTERNOON AND WITH THE SUNSHINE
THE ATMOSPHERE IS DESTABILIZING AND THUNDERSTORMS ARE EXPECTED TO
DEVELOP THIS AFTERNOON. EXPECT THAT MOST OF THE THUNDERSTORMS SHOULD
MOVE OFF TO THE EAST FAIRLY QUICKLY...MOVING OUT OF THE AREA DURING
THE EVENING. THIS AFTERNOON AND EVENING EXPECT THERE COULD BE HAIL
AND WINDS THE PRIMARY THREAT...BUT AN ISOLATED TORNADO IS NOT OUT OF
THE QUESTION.
LATER TONIGHT ANOTHER UPPER LEVEL WAVE WILL MOVE INTO THE AREA AND
BRING ANOTHER CHANCE FOR SOME THUNDERSTORMS LATER TONIGHT. MODELS
HAVE A FEW DIFFERENCES IN WHERE THE THUNDERSTORMS WILL BE WITH THE
SECOND ROUND OF STORMS. MOST OF THE MODELS TRY TO KEEP IT FURTHER TO
THE NORTH...BUT THE 4KM WRF...HRRR AND EVEN THE NAM KEEP IT A LITTLE
FURTHER SOUTH. WITH THAT IN MIND HAVE KEPT SOME LOWER POPS IN THE
SOUTH WITH HIGHER POPS IN THE NORTH. THIS COULD BRING SOME WIND AND
HEAVIER RAINS WHICH WOULD CAUSE SOME LOCALIZED FLOODING.
THE THUNDERSTORMS SHOULD LAST INTO MONDAY MORNING AGAIN BEFORE
MOVING OFF TO THE EAST. TEMPERATURES SHOULD BE A LITTLE COOLER
DURING THE DAY MONDAY.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 332 PM CDT SUN JUN 29 2014
THE BIGGEST ISSUE WILL BE PERIODIC THUNDERSTORM CHANCES FOR PARTS OF
THE CWA FOR THE BEGINNING AND LATTER PERIODS OF THE LONG TERM.
UPPER LEVEL FLOW WILL BE IN THE PROCESS OF AMPLIFYING...AS A RIDGE
DEVELOPS TO THE WEST AND A SHORTWAVE TROUGH MOVING
THROUGH/APPROACHING THE NORTH/CENTRAL PLAINS THAT WILL EVENTUALLY
SET UP A TROUGH IN THE EAST.
FOR MONDAY NIGHT...THERE COULD BE SOME SHOWERS AND THUNDERSTORMS IN
THE FAR SOUTHERN CWA IN NORTH CENTRAL KANSAS AS A LOW-LEVEL JET
DEVELOPS...WITH THE NOSE APPROACHING OUR SOUTHERN COUNTY WARNING
AREA. A STRONG STORM CAN NOT BE RULED OUT...BUT STORM PARAMETERS DO
NOT POINT TOWARD AN OVERWHELMING MOVE TOWARD MENTIONING SEVERE
WEATHER AT THIS TIME.
THE TROUGH SLIDING THROUGH ON TUESDAY IN THE NORTHERN/CENTRAL PLAINS
COULD HELP SPARK SOME SHOWERS AND THUNDERSTORMS FOR TUESDAY DURING
THE DAY ACROSS MAINLY OUR NEBRASKA COUNTIES...BUT AFTER THIS...A
SURFACE HIGH SLIDES AND WE SHOULD COOL OFF INTO THE 70S...STILL JUST
EAST OF THE DEVELOPING AND EXPANDING RIDGE...WITH ITS AXIS OVER THE
ROCKY MOUNTAINS.
THE RIDGE EXPANDS OVER OUR AREA AND WILL EFFECTIVELY SHUT OF THE
SPIGOT FOR A COUPLE OF DAYS...WHILE TEMPERATURES BEGIN TO MODERATE
ONCE AGAIN...TOWARD MORE NORMAL TEMPERATURES.
WE COULD GET SOME SHOWERS AND THUNDERSTORMS BY FRIDAY NIGHT WITH
ANOTHER LOW-LEVEL JET DEVELOPING...BUT STRONGER STORMS WILL PROBABLY
BE FARTHER NORTH WHERE THE NOSE OF THE JET WILL MORE LIKELY BE.
STORM CHANCES CONTINUE INTO THE WEEKEND AS A FEW WEAKNESSES IN THE
RIDGE ALLOW FOR SOME PERTURBATIONS TO POSSIBLY KICK UP A FEW
THUNDERSTORMS...BUT TEMPERATURES AT 700 MB APPROACHING 14 C INDICATE
THAT A HEALTHY CAP WILL BE IN PLACE AND COULD TAKE SOME WORK GETTING
THAT BROKEN. TEMPERATURES WARM UP TO SUMMER-TIME STANDARDS BY THE
WEEKEND WITH HIGHS IN THE MID 80S TO LOWER 90S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1209 AM CDT MON JUN 30 2014
VFR CONDITIONS EXPECTED THROUGH THE NEXT 24 HOURS.
CLOUDS NEAR 4000FT AGL WILL REMAIN POSSIBLE THROUGH TONIGHT. THE
SURFACE WILL REMAIN LIGHT AND VARIABLE TONIGHT...BECOMING
NORTH/NORTHWEST AT 19-21KTS DURING THE DAY MONDAY. SHOWERS AND
THUNDERSTORMS WILL BE POSSIBLE TONIGHT...BUT THE PROBABILITY OF
SUCH ACTIVITY AT GRI IS TOO LOW FOR INSERTION INTO THE TAF AT THIS
TIME. VISIBILITY RESTRICTION IS NOT EXPECTED THROUGH THE NEXT 24
HOURS.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...WESELY
SHORT TERM...JCB
LONG TERM...HEINLEIN
AVIATION...BRYANT
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1144 PM CDT SUN JUN 29 2014
.UPDATE...
ISSUED AT 1133 PM CDT SUN JUN 29 2014
WE ARE LIKELY SEEING THE LULL BEFORE THE STORM CURRENTLY WITH
LITTLE IN THE WAY OF SENSIBLE WX ONGOING ACROSS THE FA. THE 04Z
SURFACE ANALYSIS INDICATES THE SFC BOUNDARY EXTENDS FROM AROUND
KFSD TO KTIF...AND KLNX RADAR INDICATES THIS HAS SHOWN SOME
MOVEMENT TO THE SOUTH OVER THE LAST COUPLE OF HOURS. LATE EVENING
WATER VAPOR INDICATES THAT A POTENT SHORTWAVE TROUGH IS CURRENTLY
MOVING THROUGH SOUTHERN MT. FINALLY THE LATEST OBJECTIVE ANALYSIS
INDICATES THAT THE NOCTURNAL LOW-LEVEL JET IS INCREASING ACROSS
WESTERN KS INTO SOUTHWEST NEB. THE COMBINATION OF THE LARGE-SCALE
SUPPORT AND THE LOW-LEVEL JET WILL LIKELY INITIATE SEVERE
THUNDERSTORMS OVER WESTERN NEB SHORTLY. SHORT-RANGE CONVECTION
ALLOWING MODELS ARE IN GOOD AGREEMENT IN THESE MOVING EAST
OVERNIGHT AND LIKELY INTO OUR AREA AFTER 4 AM. GIVEN THE
UNSEASONABLY STRONG MID AND UPPER LEVEL JET...COUPLED WITH MUCAPE
OF 3000-4000 J/KG SEVERE WEATHER APPEARS LIKELY WITH THIS
ACTIVITY. ALTHOUGH NOT A CLIMO FAVORED TIME OF DAY WE COULD SEE A
PRETTY GOOD WIND EVENT ALONG WITH SOME SEVERE HAIL EVOLVE TOWARD
12Z ALONG AND E OF THE MO RIVER.
GOING FORECAST APPEARS TO HAVE THIS HANDLED WELL AND FORECAST
PRODUCTS WERE UPDATED EARLIER.
&&
.SHORT TERM...(TONIGHT THROUGH WEDNESDAY)
ISSUED AT 355 PM CDT SUN JUN 29 2014
CHANCE FOR SEVERE THUNDERSTORMS TONIGHT INTO MONDAY IS THE PRIMARY
FORECAST CONCERN.
AFTER MORNING THUNDERSTORMS ROLLED THROUGH PARTS OF EASTERN NEBRASKA
AND WESTERN IOWA...ATMOSPHERE HAD STABILIZED FOR A TIME INTO EARLY
AFTERNOON. HOWEVER LINGERING CLOUD COVER HAS EVAPORATED...ALLOWING
TEMPERATURES TO REBOUND INTO THE MIDDLE 80S MANY SPOTS. THIS
COMBINED WITH DEW POINTS IN THE LOWER 70S AND SOME COOLING ALOFT HAS
PRODUCED SURFACE-BASED CAPES EXCEEDING 3500 J/KG. 18Z SOUNDING AT
KOAX SHOWED 3692 J/KG OF SURFACE-BASED CAPE WITH ALMOST NO
INHIBITION. LAYER SHEAR...0-6KM...WAS 34KT...AND IS EXPECTED TO
INCREASE AS THE AFTERNOON WEARS ON. HOWEVER OUR 18Z SOUNDING SHOWS
LIFTING A MIXED-LAYER PARCEL YIELDS ONLY 1500 J/KG OF CAPE AND
INHIBITION RUNNING OVER 100. THUS MAY HAVE TO WAIT A WHILE BEFORE
CINH GOES AWAY AND HIGH INSTABILITY CAN BE REALIZED. A FEW AREAS OF
ISOLATED CONVECTION WERE NOTED AT MID AFTERNOON...BUT NONE ARE
SHOWING SIGNS OF GROWING AT THE MOMENT. MOST LIKELY AREA OF
INITIATION FOR MORE ROBUST DEVELOPMENT THIS AFTERNOON APPEARS TO BE
SETTING UP FROM CENTRAL NEBRASKA TO THE COLUMBUS...FREMONT AND
MISSOURI VALLEY AREAS. ENHANCED CUMULUS FIELD WAS STARTING TO EXPAND
HERE...WITH WEAK AREA OF FRONTAL CONVERGENCE AS PER RAP 19Z
INITIALIZATION. OTHER SUBTLE BOUNDARIES LEFT OVER FROM MORNING
STORMS COULD ALSO FOCUS STORMS THIS AFTERNOON. WHERE STORMS DO FIRE
THIS AFTERNOON...EXPECT RAPID DEVELOPMENT TOWARD STRONG/SEVERE
LEVELS IN HIGH INSTABILITY ENVIRONMENT. ORIENTATION OF LAYER SHEAR
VECTORS SUGGEST SOME SUPERCELL STRUCTURES WITH INITIAL DEVELOPMENT
OF STORMS WHICH SHOULD MOVE OFF TO THE EAST AND SOUTHEAST. CONTINUED
DEVELOPMENT AND INCREASING LOW LEVEL JET SUGGEST MCS DEVELOPMENT
WITH PROPAGATION TO THE SOUTHEAST THIS EVENING. EXPECT A HAIL AND
TORNADO THREAT WITH EARLY CONVECTION...THEN EVOLVING INTO A
HAIL...WIND AND HEAVY RAIN THREAT THROUGH THE EVENING.
EXPECT MOST OF THIS ACTIVITY TO MOVE OUT OF OUR AREA BY LATE
EVENING. THEN AN AREA OF LOW PRESSURE ROLLING OUT OF WESTERN KANSAS
ALONG FRONTAL BOUNDARY WILL ENHANCE LIFT OVER EASTERN NEBRASKA AND
AFTER MIDNIGHT...THEN SPREAD ACROSS WESTERN IOWA MONDAY MORNING.
LINGERING HIGH PRECIPITABLE WATER VALUES NEAR 2 INCHES POINT TO A
POTENTIAL OF HEAVY RAIN WITH ANY STORMS THROUGH MONDAY MORNING. SLOW-
MOVING COLD FRONT IS FORECAST TO LIMP SOUTH THROUGH MONDAY
AFTERNOON...AND CYCLONIC FLOW ALOFT COMBINED WITH WAVES RIPPLING
ALONG FRONT POINT TO REPEATED DEVELOPMENT OF MODERATE TO HEAVY RAIN
UNTIL FRONT CLEARS OUR SOUTHEAST LATE IN THE DAY.
AFTER FRONT SLIPS SOUTH OF THE FORECAST AREA MONDAY EVENING...WILL
CONTINUE OUR DRY FORECAST THROUGH TUESDAY MORNING. THEN A SHORTWAVE
ROTATING THROUGH THE NORTHERN PLAINS WILL PUSH A COLD FRONT INTO THE
AREA TUESDAY AFTERNOON WHEN ENHANCED INSTABILITY WILL LEAD TO
SCATTERED SHOWERS OR THUNDERSTORMS AS FAR SOUTH AS OMAHA. THESE
SHOULD BE DIURNALLY DRIVEN AND END AT SUNSET. TUESDAY WILL BE COOLER
AS 850 TEMPERATURES DROP INTO THE LOWER TEENS...THEN EVEN COOLER
WEDNESDAY WITH 850 TEMPS IN THE SINGLE DIGITS. MANY HIGHS BOTH DAYS
SHOULD HOLD IN THE 70S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 355 PM CDT SUN JUN 29 2014
LONG TERM PERIOD WILL START WITH MID LEVEL RIDGING BUILDING INTO THE
MIDDLE OF THE COUNTRY INTO THURSDAY...TAKING STORM TRACK TO OUR
NORTH. SURFACE HIGH PRESSURE AND ONLY SLOWLY RECOVERING 850
TEMPERATURES WILL KEEP HIGHS BELOW 80 THEN. A SHORTWAVE WILL THEN
ROLL INTO THE PLAINS FRIDAY INTO SATURDAY...BRINGING RAIN CHANCES
BACK TO OUR AREA BY FRIDAY NIGHT. COULD SEE SOME STORMS FIRE FRIDAY
AFTERNOON...BUT THE REAL FIREWORKS SHOULD HOLD OFF UNTIL THE EVENING
AND OVERNIGHT INTO SATURDAY. GFS SHOWS SYSTEM EXITING TO THE SOUTH
FOR SATURDAY NIGHT AND SUNDAY...BUT SEVERAL ENSEMBLE MEMBERS
INDICATE TIMING OF SHORTWAVE MAY BE A BIT FAST. THUS WILL CONTINUE
SMALL RAIN CHANCES INTO SUNDAY.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1133 PM CDT SUN JUN 29 2014
VFR CONDITIONS ARE GENERALLY EXPECTED THROUGH THE PERIOD EXCEPT IN
TSRA...WHICH ARE POSSIBLE AT ALL 3 SITES. THE MOST LIKELY TIME FOR
TSRA APPEARS TO BE AFTER 11Z AND THROUGH ABOUT 15Z AT ALL 3 SITES
WHEN MVFR OR EVEN SHORT TERM IFR CONDITIONS ARE POSSIBLE.
OTHERWISE A CDFNT WILL MOVE THROUGH THE TAF SITES DURING THE DAY
ON MONDAY SWITCHING THE WINDS TO NORTHWEST WITH SOME GUSTS
POSSIBLE IN THE AFTERNOON ALONG WITH DECREASING CLOUDS.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
UPDATE...BOUSTEAD
SHORT TERM...DERGAN
LONG TERM...DERGAN
AVIATION...BOUSTEAD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
130 AM EDT MON JUN 30 2014
.SYNOPSIS...
HIGH PRESSURE WILL MOVE OFF THE MID-ATLANTIC COAST THROUGH THE
MIDDLE OF THE WEEK BRINGING A SLOW WARMING TREND. AN AREA OF
TROPICAL LOW PRESSURE DEVELOPING OFF THE FLORIDA COAST MAY LIFT TO
THE NORTH LATE IN THE WEEK BRINGING INCREASING RAIN CHANCES. A COLD
FRONT WILL STALL AS IT APPROACHES THE AREA LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
AS OF 1030 PM SUNDAY...CIRRUS FROM DYING CONVECTION IN THE FOOTHILLS
AND WESTERN PIEDMONT IS SPILLING OVER THE UPPER RIDGE AND MOVING
SOUTHWARD ACROSS THE CENTRAL CAROLINAS. TYPICALLY THIN CIRRUS LIKE
THIS LOOKS A LOT WORSE ON INFRARED SATELLITE IMAGERY THAN IT DOES
FROM THE GROUND...SO I WILL MAINTAIN SKY COVER FORECASTS BELOW 15
PERCENT OVERNIGHT WHICH YIELDS "CLEAR" IN THE FORECAST PHASE-OLOGY.
WINDS HAVE ALREADY DROPPED BELOW 5 KNOTS AT ALL AIRPORT ASOS/AWOS
SITES AWAY FROM THE BEACHES. I HAVE TWEAKED LOWS DOWN SLIGHTLY
ACROSS SE NORTH CAROLINA WITH NO CHANGES ELSEWHERE. PREVIOUS
DISCUSSION FROM 730 PM FOLLOWS...
SURPRISINGLY MILD TEMPERATURES ARE EXPECTED TONIGHT AS 1023 MB HIGH
PRESSURE OFF THE MID-ATLANTIC COAST EXTENDS A RIDGE AXIS ACROSS THE
CAROLINAS. OUR FORECAST LOWS ARE IN THE MID TO UPPER 60S AWAY FROM
THE BEACHES. AT WILMINGTON OUR FORECAST LOW (67 DEGREES) IS IN THE
LOWEST 17 PERCENTILE FOR THIS DATE AND 5 DEGREES BELOW NORMAL.
DAYTIME CUMULUS WERE LIMITED TO THE VICINITY OF THE SEABREEZE
BOUNDARY THIS EVENING...MAINLY ACROSS SOUTH CAROLINA WHERE DEWPOINTS
WERE HIGHEST. DRY AIR ASSOCIATED WITH SUBSIDENCE WITHIN THE HIGH
PRESSURE TO OUR NORTH MIXED DEWPOINTS DOWN INTO THE UPPER 50S ACROSS
MUCH OF NORTH CAROLINA INTO INTERIOR NORTHEASTERN SOUTH CAROLINA.
CLEAR SKIES SHOULD PREVAIL TONIGHT WITH PRETTY DECENT RADIATIONAL
COOLING CONSIDERING THE AIRMASS AND TIME OF YEAR. FOG POTENTIAL IS
QUITE LOW OVERALL...BUT THE PEE DEE REGION OF SOUTH CAROLINA AND
ALONG THE SANTEE RIVER PROBABLY HAVE THE HIGHEST POTENTIAL WITH
FORECAST SOUNDINGS FROM THE NAM AND RUC SHOWING SUFFICIENT MOISTURE
PRESENT THROUGH 800-1000 FEET AGL WITH DRYING ALOFT. THE GFS
SOUNDINGS ARE DRIER IN THE LOW-LEVELS WHICH WOULD PRECLUDE FOG.
OUR INCREASINGLY TROPICAL LOW EAST OF FLORIDA IS NOW ALMOST 400
MILES SOUTH OF CAPE FEAR AND SHOULD STALL OVER THE NEXT 12-24 HOURS.
THE OUTERMOST CLOUD BANDS ASSOCIATED WITH THIS FEATURE WILL REMAIN
TO OUR SOUTH TONIGHT WITH NO IMPACTS LOCALLY.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
AS OF 300 PM SUNDAY...SEASONABLE AND QUIET WEATHER FOR THE SHORT
TERM AS THE CALENDAR TICKS INTO JULY. THE SENSIBLE WEATHER WILL BE
CONTROLLED BY HIGH PRESSURE DRIFTING OFF THE MID-ATLANTIC
COAST...AND A MID-LEVEL RIDGE BLOSSOMING FROM THE GULF COAST. ON
MONDAY...MID-LEVEL RIDGE AXIS WILL BE ALIGNED NEARLY
OVERHEAD...SWEEPING OFF TO THE EAST ON TUESDAY. ALTHOUGH THE RIDGE
MOVES EAST ON TUESDAY...THICKNESSES WILL ACTUALLY BE A BIT HIGHER
THAN WHAT IS EXPECTED ON MONDAY. THIS IS IMPORTANT BECAUSE ALTHOUGH
COLUMN MOISTURE INCREASES FROM MONDAY TO TUESDAY...INCREASED
SUBSIDENCE WILL SOMEWHAT OFFSET THE CONVECTIVE POTENTIAL TUESDAY.
STILL...ISOLATED TSTMS WILL BE POSSIBLE TUESDAY...WHILE MONDAY IS
EXPECTED TO REMAIN DRY. TEMPS WILL SLOWLY CLIMB EARLY WEEK...WITH
HIGHS AROUND 90 EXPECTED MONDAY...LOW 90S ON TUESDAY. LOWS MONDAY
NIGHT WILL DROP TO AROUND 70 AWAY FROM THE BEACHES...BUT ONLY INTO
THE LOW/MID 70S TUESDAY NIGHT AS SOUTHERLY RETURN FLOW DEVELOPS
AROUND THE OFFSHORE HIGH PRESSURE.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 300 PM SUNDAY...H5 RIDGE PATTERN ACROSS THE SOUTHEAST WILL
BREAK DOWN DURING THE EXTENDED AS A SHORT WAVE TROUGH SHIFTS EAST
OF THE MID-WEST AND INTO NEW ENGLAND BY THE END OF THE WEEK. OTHER
THAN SOME TYPICAL SUMMERTIME DIURNAL CONVECTION ALL EYES WILL BE
ON THE POTENTIAL DEVELOPMENT OF A TROPICAL SYSTEM OFF THE
SOUTHEAST UNITED STATES COAST. THERE IS NO CONSISTENCY EVIDENT IN
THE MODELS AT THIS TIME WITH THE NAM FAIRLY AGGRESSIVE AND ECMWF
TRACKING THE STORM OFF THE NC COAST FRIDAY. TOO MANY VARIABLES AND
INCONSISTENCIES EXIST AT THIS TIME...THUS LOW CONFIDENCE FORECAST
CONTINUES IN THE EXTENDED. MAX/MIN TEMPERATURES THROUGH THE PERIOD
WILL BE AT OR JUST ABOVE NORMAL WED/THU...WHILE THE GFS IS
POSSIBLY A CATEGORY TOO HIGH FOR MAX TEMPS FRI AND SAT.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AS OF 06Z...VFR CONDITIONS PREVAIL AT ALL THE TAF SITES CURRENTLY.
EXPECT A CANOPY OF MAINLY THIN CIRRUS THROUGH SUNRISE. EXPECT VFR
THROUGHOUT MONDAY. WINDS MORE E TO NE THROUGHOUT THE DAY MONDAY...
VEERING TO THE SE ACROSS THE COASTAL TERMINALS DURING THE AFTERNOON
AS THE SEA BREEZE DEVELOPS AND MOVES INLAND.
EXTENDED OUTLOOK...AFTERNOON AND EVENING SHOWERS EXPECTED THROUGH
THE PERIOD POSSIBLY CREATING PERIODS OF MVFR/IFR. OTHERWISE EXPECT
VFR. SOME UNCERTAINTY WITH POSSIBLE TROPICAL SYSTEM INTERACTION
WEDNESDAY THROUGH FRIDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 PM SUNDAY...VERY FEW CHANGES ARE NEEDED TO THE FORECAST
LATE THIS EVENING. PREVIOUS DISCUSSION FROM 730 PM FOLLOWS...
LOW PRESSURE HAS DRIFTED TO A POSITION ABOUT 400 MILES SOUTH OF CAPE
FEAR THIS EVENING. THIS HAS MADE WAY FOR 1023 MB HIGH PRESSURE OFF
THE MID-ATLANTIC COAST TO BUILD ACROSS THE INTERIOR CAROLINAS. EAST
TO NORTHEAST WINDS BETWEEN THIS HIGH AND THE LOW EAST OF FLORIDA
WILL CONTINUE THROUGH THE NIGHT...WITH GRADUALLY DIMINISHING WIND
SPEEDS EXPECTED AS THE PRESSURE GRADIENT WEAKENS. THE LONG ONSHORE
FLOW HAS BUILT SEAS TO AS HIGH AS 4 FEET WITHIN 20 MILES OF
SHORE...ESPECIALLY EAST OF CAPE FEAR. SEAS CURRENTLY CONSIST OF A
5-SECOND NORTHEAST WIND WAVE PLUS A 9-SECOND SOUTHEAST SWELL.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 300 PM SUNDAY...PRETTY QUIET MARINE CONDITIONS DURING THE
SHORT TERM...EVEN AS WINDS FLUCTUATE THROUGH MANY COMPASS
DIRECTIONS. HIGH PRESSURE MOVING OFF THE MID-ATLANTIC COAST DRIVES
NE WINDS AROUND 10 KTS ON MONDAY...BUT AS THIS HIGH PUSHES OFFSHORE
THE GRADIENT WILL WEAKEN...AND WINDS WILL BECOME VARIABLE UNTIL
EVENTUALLY BECOMING SW AROUND 10 KTS LATE IN THE PERIOD. SEAS WILL
BE DRIVEN BY A RESIDUAL GROUND SWELL AND A 5 SEC WIND
CHOP...CREATING 2-3 FT SEAS BOTH DAYS.
LONG TERM /WEDNESDAY THROUGH FRIDAY/...
AS OF 300 PM SUNDAY...SOUTHERLY FLOW IS EXPECTED TO PREVAIL
WEDNESDAY INTO WEDNESDAY NIGHT...WITH BACKING TO THE SOUTHEAST AND
INCREASING SPEEDS DURING THURSDAY. BIG QUESTION MARKS REMAIN
THEREAFTER DEPENDING ON THE EVOLUTION OF THE DISTURBED WEATHER OFF
THE GA/FL COASTS. HAVE NUDGED SEAS UP A FOOT FROM THE PREVIOUS
FORECAST AS THE FETCH WILL LIKELY DIRECT MORE ENERGETIC WAVES
TOWARD THE COAST. SMALL CRAFT CONDITIONS ARE POSSIBLE BY THE END
OF THE WEEK...AGAIN ALL DEPENDING ON WHAT HAPPENS WITH THE
AFOREMENTIONED AREA OF DISTURBED WEATHER.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...JDW
LONG TERM...SRP
AVIATION...MAC/RJD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
128 AM EDT MON JUN 30 2014
.SYNOPSIS...AN UPPER LEVEL RIDGE OVER THE REGION WILL WEAKEN BY MID
WEEK AS AN UPPER LEVEL TROUGH AND ATTENDANT COLD FRONT APPROACH FROM
THE NORTHWEST. MEANWHILE...AN AREA OF DISTURBED WEATHER OFFSHORE THE
SOUTHEAST COAST MAY DEVELOP INTO A TROPICAL CYCLONE THAT COULD
AFFECT PORTIONS OF THE SOUTHEAST COAST MID TO LATE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 920 PM SUNDAY...
LATEST REGIONAL RADAR SHOWS THE THIN LINE OF SHOWERS AND A FEW TSTMS
MOVING ACROSS THE FOOTHILLS AND SOON APPROACHING THE WESTERN
PIEDMONT. THESE SHOWERS HAVE BEEN TRENDING DOWNWARD IN COVERAGE AND
INTENSITY...AND EXPECT THIS TREND TO CONTINUE GIVEN THE CURRENT
MESOANALYSIS WHICH SHOWS RELATIVELY DRIER AIR OVER CENTRAL NC.
NEARLY ALL THERMODYNAMIC AND MOISTURE PARAMETERS SUGGEST THAT THESE
SHOWERS WILL DISSIPATE EITHER JUST BEFORE...OR SHORTLY AFTER
REACHING OUR FAR WESTERN ZONES. WOULDN`T BE SURPRISED TO SEE PLACES
LIKE WINSTON-SALEM AND LEXINGTON SEE A VERY BRIEF LIGHT SHOWER
AROUND MIDNIGHT...BUT THAT`S ABOUT AS FAR EAST AS THE SHOWERS WILL
MAKE IT BEFORE COMPLETELY DISSIPATING. THIS SCENARIO IS WELL-
SUPPORTED BY LATEST RUN OF THE HRRR. OTHERWISE FOR THE REST OF THE
OVERNIGHT...LOOK FOR MID AND HIGH CLOUDS CURRENTLY TO OUR WEST TO
SPREAD EAST. LOW TEMPS IN THE MID 60S STILL LOOKS ON-TRACK GIVEN
CURRENT TEMPS/DWPTS AND CLOUDS. ANY FEW SPOTS THAT REMAIN MOSTLY
CLEAR SKIES OVERNIGHT MAY EVEN BE ABLE TO DIP DOWN A LITTLE
COOLER...CLOSER TO 60. OTHER THAN A FEW TWEAKS FOR CURRENT
CONDITIONS...NO MAJOR GRID CHANGES PLANNED FOR THE EVENING UPDATE.
PREVIOUS NEAR TERM DISCUSSION AS OF 250 PM SUNDAY... THE LATEST
SURFACE ANALYSIS IS LITTLE CHANGED FROM EARLIER TODAY... WITH HIGH
PRESSURE OVER CENTRAL NORTH CAROLINA AND A DIFFUSE FRONT OVER THE
WESTERN CAROLINAS...ESSENTIALLY SEPARATING SURFACE DEW POINTS
LARGELY IN THE 50S FROM DEW POINTS WELL INTO THE 60S OR NEAR 70F.
MAIN WEATHER CONCERN THROUGH THE EVENING HOURS IS THE PROGRESS OF A
NARROW BAND OF MID-LEVEL MOISTURE...WITH A WEAK 700MB WAVE AS
ANALYZED BY THE MAJORITY OF NWP ON THE GRADIENT OF HIGHER 850MB
THETA-E AND PRECIPITABLE WATER...MOVING EAST INTO CENTRAL NORTH
CAROLINA. HIGH PRESSURE AND BELOW NORMAL OVERALL MOISTURE TO THE
EAST OF THE WAVE HAS RESULTED IN A STRUGGLE OF THE CLOUDS TO MOVE
MUCH PAST THE WESTERN TWO TIERS OF COUNTIES OR SO...WITH PATCHY RAIN
CONFINED LARGELY TO FORSYTH COUNTY AND INTO WESTERN PERSON COUNTY.
WITH LOW DEW POINTS IN PLACE...MUCH OF ANY PRECIPITATION THIS
EVENING COULD BE SPRINKLES...AND THE LATEST VISIBLE IMAGERY HAS
SHOWN SOME EROSION OF THE WEST END OF THE CLOUD BAND AS THE RAGGED
EAST EDGE OF THE CLOUDS MOVES SLOWLY EAST. THE NAM AND THE GFS
FORECAST THE MID-LEVEL WAVE TO STEADILY MOVE EAST ACROSS CENTRAL
NORTH CAROLINA OVERNIGHT...AND SOME OF THE BUFR SOUNDINGS WOULD
INDICATE A PERIOD OF MOSTLY CLOUDY CONDITIONS ESPECIALLY TOWARD KRDU
AND KRWI OVERNIGHT. GRIDDED GUIDANCE FROM THE GFS WOULD PROVIDE FOR
CONSIDERABLE CLOUD COVER OVERNIGHT...BUT THE LATEST TRENDS AND THE
MOISTURE FIELDS...PARTICULARLY FROM THE LATEST RAP...WOULD SUGGEST
THAT IS TOO PESSIMISTIC. FOR THIS FORECAST...WILL AVERAGE A PARTLY
CLOUDY SKY OVERNIGHT IN CENTRAL NORTH CAROLINA WITH THE LEAST AMOUNT
OF CLOUDS TOWARD KFAY AND KCTZ. PRECIPITABLE WATER VALUES SHOULD
CREEP UP OVERNIGHT AS THE UPPER RIDGE AXIS MOVES VERY SLOWLY EAST...
AND WILL FORECAST LOWS MOSTLY WITH A BLEND OF THE MAV AND MET MOS
GUIDANCE...THOUGH CERTAINLY TOWARD THE WARMER MET NEAR KRWI...MOSTLY
IN THE MID 60S.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 250 PM SUNDAY...
THE NAM AND THE GFS FORECAST PRECIPITABLE WATER VALUES INCREASING BY
AFTERNOON IN CENTRAL NORTH CAROLINA TO VALUES NOW AT OR ABOVE
NORMAL...TO NEARLY TWO INCHES ON THE GFS BY 00Z TUESDAY...AND WHILE
NOT SO HIGH ON THE NAM STILL TO ABOUT 1.8 INCHES BY THE SAME TIME.
AS THE MOISTURE INCREASES...WEAK SURFACE HIGH PRESSURE REMAINS...
LEAVING LITTLE LOW-LEVEL MECHANISMS FOR STRONG LIFT. BOTH THE NAM
AND THE GFS SUGGEST UPPER-LEVEL CONVERGENCE FOR THIS PART OF THE
FORECAST...AND ONLY WEAK 850MB CONVERGENCE MAINLY TOWARD THE WESTERN
PIEDMONT WHERE THE BETTER LIFT...RELATIVE TO THE REST OF CENTRAL
NORTH CAROLINA...IS FORECAST. GFS AND NAM BUFR SOUNDINGS SHOW THAT
ESSENTIALLY THE AIR MASS OVER CENTRAL NORTH CAROLINA IS CAPPED TO
DEEP CONVECTION EXCEPT TOWARD THE TRIAD...WHERE THERE WOULD BE
ENOUGH INSTABILITY IF A STORM COULD DEVELOP OR MOVE INTO THE AREA TO
BE SUSTAINED. MLCAPE IN THE LOWEST KM IS UNDER 1000J/KG AND
DOWNDRAFT CAPE IS WEAK...UNDER 400J/KG...SO CURRENTLY THE CHANCES OF
VIGOROUS CONVECTION APPEARS LOW. LIFTED INDICES MONDAY AFTERNOON ARE
TO -2C ON THE NAM WHICH GENERATES NO QPF AT ALL IN CENTRAL NORTH
CAROLINA...AND TO -4C OR SO ON THE GFS WHICH DOES PROVIDE FOR A
LARGER AREA OF QPF OVER THE WESTERN PIEDMONT MONDAY AFTERNOON WEST
OF U.S. 1...ALTHOUGH WITH LESSER MOS GUIDANCE POPS THAN THE NAM.
SOME OF THE HRRR WRF GUIDANCE WOULD SUGGEST ISOLATED TO WIDELY
SCATTERED SHOWERS AND STORMS POSSIBLE WEST OF U.S. 1 MONDAY
AFTERNOON INTO THE EVENING SO WILL BLEND THE NAM...GFS...AND THE WRF
GUIDANCE AND SHOW THE POTENTIAL FOR MAINLY ISOLATED SHOWERS AND
THUNDERSTORMS IN THAT AREA MONDAY AFTERNOON INTO MONDAY EVENING
BEFORE WANING DIURNALLY. HIGHS MONDAY AROUND 90 ON AVERAGE OVER
CENTRAL NORTH CAROLINA WITH OVERNIGHT LOWS MONDAY NIGHT IN THE UPPER
60S TO NEAR 70...CLOSER TO THE WARMER MOS GUIDANCE DUE TO THE
INCREASINGLY MOIST AIR. -DJF
TUE/TUE NIGHT: THE UPPER LEVEL RIDGE CURRENTLY IN PLACE OVER THE
SOUTHEASTERN CONUS WILL BEGIN TO FLATTEN TUE/TUE NIGHT AS AN UPPER
LEVEL LOW (CURRENTLY IN MANITOBA) TRACKS ESE TO THE UPPER GREAT
LAKES...RESULTING IN HEIGHT FALLS AND STRENGTHENING SOUTHWEST FLOW
ALOFT ACROSS THE NORTHERN MID-ATLANTIC...THOUGH THE HEIGHT GRADIENT
WILL CHANGE LITTLE FURTHER SOUTH IN THE CAROLINAS. A PRE-FRONTAL
TROUGH IN ADVANCE OF A COLD FRONT ATTENDANT THE AFOREMENTIONED UPPER
LEVEL WAVE WILL PROGRESS INTO THE MID-ATLANTIC TUE AFT/EVE. FORCING
FOR ASCENT WILL BE CONFINED TO WEAK/SHALLOW CONVERGENCE IN VICINITY
OF THE PIEDMONT TROUGH AND ALONG THE SEABREEZE...THE LATTER OF WHICH
COULD PENETRATE WELL INLAND VIA ONSHORE FLOW (S/SE). MID-LEVEL LAPSE
RATES ARE PROGGED TO STEEPEN FROM THE WEST TUE AFT/EVE AS A MODIFIED
EML ADVECTS INTO THE SOUTHERN APPALACHIANS. THOUGH THIS FEATURE WILL
RESULT IN ENHANCED DESTABILIZATION ACROSS THE WESTERN PIEDMONT (UP
TO 2000 J/KG MLCAPE)...IT WILL ALSO RESULT IN AN ENHANCED MID-LEVEL
CAP AND /DRY MID-LEVEL AIRMASS/ THAT COULD PRECLUDE DEVELOPMENT IN
THE PRESENCE OF SUCH WEAK FORCING. HOWEVER...GIVEN A POTENTIAL FOR
MOUNTAIN CONVECTION TO DRIFT EASTWARD IN AN ENV. WHICH WOULD FAVOR
STRONG COLD POOLS...A SLIGHT CHANCE OF CONVECTION APPEARS WARRANTED
IN THE FAR WESTERN PIEDMONT. WILL ALSO INDICATE A SLIGHT CHANCE OF
CONVECTION IN THE SOUTHEAST COASTAL PLAIN IN ASSOC/W ONSHORE FLOW IN
THE PRESENCE OF A WEAKER MID-LEVEL CAP (ALBEIT WITH WEAKER
INSTABILITY). EXPECT HIGHS TUE IN THE 90-95F RANGE...WARMEST IN THE
SANDHILLS. LOWS TUE NIGHT WILL BE MUGGY GIVEN ONSHORE FLOW...IN THE
LOWER TO MID 70S. -VINCENT
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY NIGHT/...
AS OF 325 PM SUNDAY...
WEDNESDAY THROUGH FRIDAY: EXPECT ABOVE NORMAL HIGHS AND
CLIMATOLOGICAL CHANCES FOR CONVECTION ON WED AS SOUTHWEST FLOW ALOFT
ADVECTS A WARMER MID-LEVEL AIRMASS INTO THE REGION...FOLLOWED BY
NEAR NORMAL HIGHS AND ABOVE NORMAL CHANCES FOR CONVECTION THU/FRI IN
ASSOC/W INCREASINGLY CYCLONIC FLOW ALOFT OVER THE MID-ATLANTIC/
CAROLINAS AND LOW-LEVEL CONVERGENCE ASSOC/W A COLD FRONT ATTENDANT
AN UPPER LEVEL TROUGH APPROACHING FROM THE WEST. HOWEVER...FORECAST
UNCERTAINTY HAS INCREASED ACROSS THE SOUTHEAST CONUS IN ASSOC/W THE
POTENTIAL FOR HOMEGROWN TROPICAL CYCLONE DEVELOPMENT ALONG THE
SOUTHEAST COAST WED-FRI. IF A TROPICAL CYCLONE DEVELOPS AND TRACKS
ALONG/JUST OFFSHORE THE CAROLINA COAST...THERE ARE TWO PRIMARY
SCENARIOS: 1) IF THE TRACK IS FURTHER OFFSHORE AND/OR THE
APPROACHING TROUGH IS SLOWER...PRECIP CHANCES COULD BE LOWER THAN
OTHERWISE EXPECTED IN THE COASTAL PLAIN IN ASSOC/W SUBSIDENCE AND A
DRY MID-LEVEL AIRMASS ON THE WESTERN PERIPHERY OF THE SYSTEM...OR 2)
IF THE TRACK IS CLOSER TO THE COAST (OR INLAND) AND THE TROUGH
APPROACHES AS PROGGED BY 12Z GUIDANCE...THEN THE ENVIRONMENT WOULD
FAVOR A `LEFT OF TRACK` SCENARIO WITH POTENTIALLY SIGNIFICANT
PRECIPITATION ACROSS PORTIONS OF EASTERN NC. GIVEN ABOVE NORMAL
UNCERTAINTY...WILL MAKE FEW CHANGES TO THE FORECAST FOR THIS PERIOD.
SATURDAY THROUGH MONDAY: THE PROGRESSIVE UPPER LEVEL TROUGH MOVING
EAST INTO THE REGION WED-FRI IS EXPECTED TO TRACK OFFSHORE THE MID-
ATLANTIC COAST EARLY SATURDAY...STEERING THE POTENTIAL TROPICAL
CYCLONE OFFSHORE WITH EVENTUAL INTERACTION /EXTRATROPICAL
TRANSITION/ OCCURRING WELL NORTHEAST OF CENTRAL NC OFF THE MID-
ATLANTIC COAST. WITH SYNOPTIC SUBSIDENCE AND A DRIER /MORE STABLE/
AIRMASS IN PLACE IN THE WAKE OF THE COLD FRONTAL PASSAGE...EXPECT
NEAR NORMAL TEMPS AND DRY CONDITIONS THROUGH THE WEEKEND. -VINCENT
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AS OF 125 AM MONDAY...
24-HOUR TAF PERIOD: HIGH CONFIDENCE THAT VFR CONDITIONS WILL PERSIST
THROUGH THE TAF PERIOD. WINDS WILL BE CALM TO LIGHT AND VARIABLE
OVERNIGHT. THE RIDGE...BOTH ALOFT AND AT THE SURFACE...WILL WEAKEN
AS THE SURFACE HIGH PULLS AWAY TO THE NE...RESULTING IN A SOUTH TO
SOUTHWEST RETURN FLOW MONDAY AFT/EVE. WITH INCREASED MOISTURE
ADVECTION INTO THE WEST (KINT/KGSO)...EXPECT BKN TO OVC HIGH
CLOUDS...WITH A FEW LOWER CLOUDS IN THE 3500 TO 5000 FT RANGE
THROUGH THE PERIOD. THOUGH SHOWERS/STORMS ARE POSSIBLE AT THE FAR
WEST TERMINALS MONDAY AFT/EVE...CHANCES ARE NOT VERY HIGH AND
COVERAGE SHOULD BE ISOLATED...THUS WILL NOT INCLUDE MENTION IN THIS
TAF ISSUANCE. -KC
LOOKING AHEAD: WITH HIGH PRESSURE IN CONTROL BOTH AT THE SURFACE AND
ALOFT...TYPICAL DIURNAL SUMMERTIME CONVECTION IS EXPECTED ONCE AGAIN
ON TUESDAY. THEN FOR THE REMAINDER OF THE WEEK...THE HIGH PRESSURE
SYSTEM IS EXPECTED TO WEAKEN AS AN UPPER LEVEL TROUGH/SURFACE FRONT
APPROACHES THE REGION...RESULTING IN A BETTER CHANCE FOR AFTERNOON
SHOWERS AND THUNDERSTORMS. OTHERWISE...SHOULD SEE A BRIEF PERIOD OF
EARLY MORNING FOG/LOW STRATUS...ESPECIALLY FOR THE LATTER HALF OF
THE WEEK. -KRD
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...NP/DJF
SHORT TERM...DJF/VINCENT
LONG TERM...VINCENT
AVIATION...KC/KRD
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
141 AM EDT MON JUN 30 2014
.SYNOPSIS...
OFFSHORE HIGH AND LOW PRESSURE SYSTEMS WILL CONTINUE TO BRING IN
HIGH AMOUNTS OF ATLANTIC MOISTURE...POSSIBLY PRODUCING LOCALIZED
FLOODING EVENTS THIS EVENING. THE WEATHER PATTERN WILL CHANGE ON
MONDAY WITH A TREND BACK TO A TYPICAL SUMMERTIME REGIME THROUGH THE
END OF THE WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
AT 130 AM EDT MONDAY...FCST IS IN DECENT SHAPE AS T/TDS REMAIN
RATHER STEADY STATE WITH CALM WINDS AND PLENTY OF CI OVERHEAD. MADE
DOWNWARD ADJS TO THE POP GRIDS...ESP ERN HALF...AND LEFT LOW END
CHANCE ACROSS THE SW NC MTNS AND NE GA TO ACCOUNT FOR WEAKENING
SHRA/TSTMS REACHING WITHIN THE NEXT FEW HRS.
AT 1030 PM EDT SUNDAY... CONVECTIVE PRECIPITATION AND TRAILING AREAS
OF LIGHT RAIN ARE DIMINISHING AS THEY MOVE INTO EASTERN PORTION OF
THE CWA. ACCORDINGLY... POPS HAVE BEEN INCREASED A BIT IN THE EAST
AND DECREASED SUBSTANTIALLY IN THE WEST. NEARLY ALL PRECIPITATION
SHOULD END BY 2 AM.
PREVIOUS DISCUSSIONS...
AT 730 PM... NARROW LINE OF CONVECTIVE RAIN MOVING INTO CENTRAL
PORTION OF THE CWA HAS LEFT BEHIND AREAS OF RAIN IN THE WEST. RADAR
TRENDS INDICATE THE PRECIPITATION IN THE WEST IS ON THE WANE... BUT
CONVECTIVE LINE IS MAINTAINING ITS STRENGTH. THE CONVECTIVE
PRECIPITATION SHOULD DIMINISH AS IT MOVES INTO EASTERN CWA. THE
CAPE... LI... AND K INDEX ALL SHOW A TIGHT DECREASING GRADIENT OVER
THE EASTERN ZONES. EXPECT THE ONGOING CONVECTION WILL WEAKEN AS IT
APPROACHES THAT AREA. EARLY EVENING UPDATE HOLDS ON TO HIGH POPS IN
THE WEST TAILING OFF TOWARD THE EAST. WILL MONITOR WITH INTENTION OF
INCREASING POPS IN THE EAST IF EXPECTED DISSIPATION DOES NOT OCCUR.
AT 630 PM EDT SUNDAY... PREVIOUSLY DISCUSSED WEATHER AND POPS STILL
APPLY BUT POPS HAVE BEEN INCREASED OVER WESTERN ZONES TO ACCOUNT FOR
EXPANSIVE LIGHT TO MODERATE RAIN FOLLOWING CONVECTIVE STORMS.
LOCALLY HEAVY RAIN WILL BE A CONCERN THROUGH THE EVENING ALONG AND
NEAR THE BLUE RIDGE ESCARPMENT AND INTO THE FOOTHILLS.
AT 430 PM EDT SUNDAY... FAIRLY EXTENSIVE AREA OF CONVECTIVE STORMS
AND ASSOCIATED AREAS OF LIGHT TO MODERATE RAIN WERE MOVING INTO TO
THE WESTERN PORTION OF THE FORECAST AREA LATE THIS AFTERNOON.
CONVECTION IS FEEDING ON CAPE VALUES GREATER THAN 1500 J/KG IN A
TONGUE OF HIGH ENERGY EXTENDING FROM SOUTHEAST GEORGIA INTO WESTERN
UPSTATE SOUTH CAROLINA. HAVE INCREASED POPS OVER WESTERN ZONES TO
ACCOUNT FOR THE LATE AFTERNOON AND EVENING STORMS. HRRR HAS A
REASONABLE... BUT FAR FROM EXACT... DEPICTION OF THE CONVECTION. THE
HRRR TREND FITS THE FORECAST CAPE FIELD WHICH FOLLOWS A TYPICAL
DIURNAL DOWNWARD TREND AROUND SUNSET AND DURING THE SUBSEQUENT
HOURS. WILL LOWER POPS ACCORDINGLY DURING THE EVENING. HMT-SOUTHEAST
PROFILERS IN THE FOOTHILLS INDICATE A VERY WEAK UPSLOPE FLOW NEAR
THE SURFACE BUT LIGHT WINDS BECOME NEARLY PARALLEL TO THE TERRAIN
ABOVE APPROXIMATELY 3K FEET. CAPE VALUES REMAIN QUITE LOW OVER
EASTERN ZONES AND SATELLITE IMAGERY SHOWS LITTLE IN THE WAY OF
CONVECTIVE CLOUDS OTHER THAN FAIR WEATHER CUMULUS.
AT 230 PM EDT SUNDAY...THE EAST COAST UPPER RIDGE WILL DEAMPLIFY
TONIGHT AND MONDAY...LEADING TO A ZONAL FLOW OVER THE SOUTHERN
APPALACHIANS. A SLOW MOVING UPPER LEVEL IMPULSE IS EXPECTED TO
APPROACH THE SOUTHERN APPALACHIANS THIS EVENING..CROSSING THE
MOUNTAINS AROUND DAYBREAK...AND MOVING ACROSS THE FOOTHILLS AND
PIEDMONT ON MONDAY.
MEANWHILE...A STATIONARY FRONT WILL SLOWLY WEAKEN OVER THE SAVANNAH
RIVER VALLEY...AND HIGH PRESSURE WILL DRIFT OFF THE EAST COAST. A
SURFACE LOW DRIFTING SLOWLY SOUTH OFF THE FL COAST IS BEING
MONITORED BY NHC FOR SIGNS OF TROPICAL DEVELOPMENT. DEEP MOISTURE
REMAINS BANKED UP AGAINST THE APPALACHIANS.
AFTERNOON CONVECTION IS EXPECTED TO LINGER INTO THE EVENING...WITH A
GRADUAL SHIFT FROM THE BLUE RIDGE EAST IN A WEAK STEERING FLOW.
HEAVY RAINFALL WILL BE POSSIBLE WITH SLOW MOVING CELLS...PRESENTING
THE POSSIBILITY OF LOCALIZED FLOODING. WITH ONLY MODEST INSTABILITY
PRESENT...SEVERE WEATHER IS NOT EXPECTED OF GREAT CONCERN. MINIMUM
TEMPERATURES WILL RUN SLIGHTLY ABOVE CLIMATOLOGY IN ABOVE NORMAL
MOISTURE. DAYBREAK FOG WILL BE MOST LIKELY IN MOUNTAIN VALLEYS...
AND RAIN SOAKED AREAS IN THE LEE OF THE MOUNTAINS.
INSTABILITY IS ONLY EXPECTED TO BE SLIGHTLY GREATER ON MONDAY...
SLIGHTLY DRIER AIR ALOFT WILL BE AVAILABLE FOR EVAPORATIVE COOLING.
ALTHOUGH MOISTURE APPEARS SLIGHTLY MORE LIMITED IN MODEL
SOUNDINGS...STEERING FLOW REMAINS WEAK...AND HEAVY RAIN STILL
REMAINS A CONCERN WITH SLOW MOVING CONVECTION PROVOKED BY THE UPPER
LEVEL IMPULSE. DESPITE LOWER HEIGHTS ALOFT WITH THE BREAKDOWN OF
THE UPPER RIDGE...SURFACE TEMPERATURES ARE EXPECTED TO BE WARMER AS
THE AIR MASS MODIFIES AND SW FLOW ENSUES IN THE WAKE OF THE SURFACE
HIGH.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
AT 230 PM EDT SUNDAY. FOR THE PERIOD MONDAY NIGHT THROUGH WEDNESDAY.
A S/W WILL BE CROSSING OUR FORECAST AREA MONDAY NIGHT...WHILE HAVING
THE OPPORTUNITY TO INTERCEPT MOISTURE AND INSTABILITY FROM THOSE
LOCATIONS THAT DID NOT HAVE THE ATMOSPHERE WORKED OVER DURING THE
DAYLIGHT HOURS MONDAY. WE WILL THEN ALLOW POPS TO LOWER DURING THE
WEE HOURS MONDAY/PREDAWN TUESDAY...AS THE S/W PASSES BY AND
SUBSIDENCE PREVAILS.
ON TUESDAY WE ARE CAUGHT IN THE MIDDLE OF DUAL AMPLIFYING TROFS TO
OUR NORTH AND NORTHWEST...AND THE SYSTEM OFF THE EAST COAST OF
FLORIDA. IT APPEARS WE MAY BE IN A CONVECTIVE LULL WITH INHIBITION
NOTED ON VARIOUS SOUNDINGS...EXCEPT IN THE MOUNTAINS. THEREFORE HAVE
ONLY A SLIGHT CHANCE POPS...ALBEIT A TAD HIGHER IN THE
MOUNTAINS...WHERE SOME MINOR LOW LEVEL CONVERGENCE WAS NOTED...AND
SWLY UPSLOPE FLOW PREVAILS. H85 THERMAL PATTERN SUGGESTS TEMPS ON
THE WAY UP TUESDAY...AND THIS IS SUPPORTED BY NEARLY ALL GUIDE
TEMPERATURE PACKAGES.
ANY ISOLATED CONVECTION TUESDAY EVENING WILL END WITH LOSS OF
HEATING FOLLOWED BY FAIR SKIES.
A BIT MORE INTERESTING WEDNESDAY WITH LESS CONVECTIVE INHIBITION...
CONSIDERABLE "FAT" LOOKING CAPE...AND SOME WEAK BOUNDARY DRIFTING
INTO THE REGION FROM THE WEST. THEREFORE HAVE EDGED POPS UPWARD INTO
THE CHANCE CATEGORY...WITH A VERY WARM AND JUICY AIRMASS STILL IN
PLACE.
MEANWHILE...APPARENT TEMPERATURES ON BOTH TUESDAY AND WEDNESDAY WILL
RANGE FROM 95 TO 100 DEGREES...IN THE WESTERN PIEDMONT OF NC/UPSTATE
SC AND PARTS OF NE GEORGIA.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 200 PM EDT SUNDAY...MODEL AGREEMENT STILL VERY GOOD ON THE
DEVELOPMENT OF HIGH AMPLITUDE PROGRESSIVE UPPER LEVEL PATTERN FOR
THE MEDIUM RANGE. A SLOW-MOVING TROF AXIS SHUD ENTER THE GREAT LAKES
TO THE TN VALLEY BY EARLY THURSDAY...THEN GRADUALLY CROSS THE
APPALACHIANS AND EAST COAST FRIDAY THRU SATURDAY. THIS TROF IS
EXPECTED TO PICK UP A TROPICAL DISTURBANCE (WHICH MAY BE A TROPICAL
STORM OR HURRICANE BY THEN)...FROM THE FL ATLANTIC COAST REGION. THE
LATEST NHC FCST IS CLOSE TO THE 00Z ECMWF...WITH A LIKELY TROPICAL
STORM LIFTING NE JUST OFFSHORE...AHEAD OF A COLD FRONT THAT IS
EXPECTED TO CROSS OUR AREA FROM THE WEST ON THURSDAY. SO AT THIS
TIME...STILL NOT EXPECTING ANY DIRECT IMPACT FROM THAT SYSTEM. AS
FOR THE FRONT ITSELF...GUIDANCE SHOWS ENHANCED CAPE IN THE WARM
SECTOR ALONG AND AHEAD OF THE BNDRY...WITH DECENT QPF RESPONSE.
TAKING A BLEND OF WPC GRIDS AND THE MODEL CONSENSUS...POPS WERE
BUMPED UP TO HIGH-END CHC TO LOW-LIKELY FOR THURSDAY ACRS PRETTY
MUCH THE ENTIRE CWFA.
SOME DRIER AIR AND FALLING THICKNESSES SHUD RESULT IN ONLY ISOLD TO
WIDELY SCATTERED DIURNALLY-DRIVEN CONVECTION FOR FRIDAY AND
SATURDAY...WITH TEMPS BACK TO NEAR OR EVEN A DEG OR TWO BELOW NORMAL
FOR NEXT WEEKEND.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AT KCLT...NOT ANTICIPATING FLIGHT RESTRICTIONS OVERNIGHT. SOME ISOL
LIFR HAS MAD IT INTO THE UPSTATE...BUT HAVE SEEN NOTHING ON THE FOG
PRODUCT OR GUIDANCE TO INDICATE A SPREAD TO THE EAST. A GOOD
AMOUNT OF CI SHOULD HINDER RADIATIONAL COOLING AND TDD/S ARE ARND
5 F CURRENTLY. SCT AFTERNOON CONVECTION IS PROBABLE IN A
DESTABILIZING SW/LY FLOW...SO A PROB30 TSTM WILL BEGIN AFTER 18Z.
ELSEWHERE...LIFR CIGS ARE NOTED AT KAVL AND GMU. BELIEVE KAVL WILL
BE SOCKED IN PRETTY MUCH ALL NIGHT WITH CALM CONDS. KGMU IS MORE
UNCERTAIN WITH SURROUNDING STCU NOT DEFINED ON SAT NOR SURROUNDING
OBS. ALL SITES WILL GET A TEMPO MVFR CIG OR VSBY AFT 08Z/09Z THROUGH
DAYBREAK. A WEAK BNDRY MOVES IN FROM THE WEST WITH VORT ENERGY
CROSSING OVERHEAD IS ENUF TO INCLUDE A PROB30 TSTM ALL SITES AFTER
18Z OR SO.
OUTLOOK...A RETURN TO MORE TYPICAL SUMMERTIME CONDITIONS IS EXPECTED
THROUGH THE WEEK...WITH MORNING CIG AND VSBY RESTRICTIONS IN FOG
MOST LIKELY IN THE MOUNTAINS.
CONFIDENCE TABLE...
05-11Z 11-17Z 17-23Z 23-05Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 97% HIGH 100% HIGH 100%
KAVL HIGH 91% HIGH 93% LOW 57% LOW 57%
KHKY HIGH 100% HIGH 94% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 86% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...ARK
NEAR TERM...LGL/SBK
SHORT TERM...TS
LONG TERM...ARK
AVIATION...SBK
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
307 AM CDT MON JUN 30 2014
.DISCUSSION...
CURRENTLY...A WEAK LEFTOVER BOUNDARY STRETCHES NW/SE ACROSS WEST
TENNESSEE THIS MORNING. THE HRRR HAS BEEN TRYING TO DEVELOP
CONVECTION INVOF THIS BOUNDARY OVERNIGHT BUT THE 850 MB FLOW OF
15-20 KTS DOES NOT SEEM TO BE ENOUGH TO GENERATE ANY CONVECTION
WEST OF THE TN RIVER. SKIES RANGE FROM MOSTLY CLEAR IN THE WEST TO
MOSTLY CLOUDY NEAR THE TN RIVER. VERY MOIST AND WARM ACROSS THE
DELTA WHERE DEWPOINTS ARE IN THE MID 70S.
TODAY...WILL LEAVE A SMALL POPS ALONG THE TN RIVER VALLEY THIS
MORNING TO COVER ANY POTENTIAL DEVELOPMENT. THE BIG STORY TODAY IS
THE UPPER RIDGE BUILDING INTO THE AREA WITH INCREASINGLY HOT AND
HUMID CONDITIONS. EXPECT DEWPOINTS TO REMAIN QUITE HIGH TODAY DUE
TO ALL THE RECENT RAINS. THE 00Z NAM IS A LITTLE LESS AGGRESSIVE
WITH 925 MB TEMPS THAN PREVIOUS RUNS SO BACKED OFF HIGHS ABOUT A
DEGREE. THE ADDED LOW LEVEL MOISTURE DUE TO RECENT RAIN WILL MAKE
UP FOR IT AS DEWPOINTS WILL REMAIN IN THE MID 70S THIS MORNING
BEFORE MIXING OUT A BIT THIS AFTERNOON. HEAT INDEX VALUES WILL HIT
100F BY ABOUT NOON.
TONIGHT...WARM AND MUGGY WITH MOSTLY CLEAR SKIES. LOWS WILL BE IN
THE LOWER TO MID 70S.
TUESDAY...ANOTHER HOT AND HUMID DAY. TEMPS WILL CLIMB A COUPLE
DEGREES HIGHER PUSHING HEAT INDEX VALUES IN THE LOW 100S WITH
PLENTY OF SUNSHINE. AN UPPER TROF PUSHING THROUGH THE GREAT LAKES
WILL PUSH A COLD FRONT TOWARD THE MIDSOUTH IN THE AFTERNOON
PERHAPS BRINGING SOME SHOWERS AND THUNDERSTORMS TO NORTHERN
LOCATIONS. THE AIRMASS WILL BE QUITE UNSTABLE AND A FEW STRONG
STORMS ARE POSSIBLE ACROSS THE NORTH.
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...00Z MODELS INDICATE THE
GREAT LAKES TROF WILL BE A LITTLE DEEPER AND EXTEND A LITTLE
FURTHER INTO THE SOUTHERN STATES BY WEDNESDAY WHICH HELPS DRIVE
THE FRONT THROUGH MORE QUICKLY ON WEDNESDAY. SHOWER/THUNDERSTORM
CHANCES WILL MOVE SOUTH TUESDAY NIGHT AND WEDNESDAY WITH THE
FRONT. BY WEDNESDAY EVENING MOST OF THE PRECIP WILL HAVE EXITED
THE REGION. MODELS ARE INDICATING A GOOD DEAL OF INSTABILITY
ACROSS THE AREA THOUGH WIND SHEAR IS FAIRLY WEAK AT THE SOUTHERN
END OF THE UPPER TROF. A FEW STRONG STORMS ARE POSSIBLE ACROSS THE
AREA AS THE FRONT MOVES THROUGH.
THURSDAY THROUGH SUNDAY...HIGH PRESSURE INTO THE AREA ON THURSDAY
AND CONTINUE INTO THE WEEKEND. BELOW NORMAL TEMPERATURES ARE
EXPECTED WITH HIGHS IN THE 80S THURSDAY AND FRIDAY AND LOWS IN THE
60S. MAY EVEN SEE SOME 50S IN THE TYPICAL COOLER SPOTS. TEMPS WILL
BEGIN TO WARM BACK INTO THE LOWER 90S BY SUNDAY.
SJM
&&
.AVIATION...
06Z TAFS
MAIN AVIATION FORECAST CONCERN OVERNIGHT REMAINS LOW LEVEL STRATUS
FORMATION POTENTIAL. LOW LEVEL WINDS SHOULD BE SUFFICIENT TO KEEP
VSBY PREVAILING MVFR OR BETTER...WHILE MIDLEVEL DECK NEAR MKL DOWN
TO TUP SHOULD REDUCE FOG FORMATION POTENTIAL. THIS MIDLEVEL DECK
WILL PROVIDE A SLIGHT CHANCE OF SHOWERS...WHICH SHOULD REMAIN EAST
OF MEM OVERNIGHT.
PWB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
420 AM CDT MON JUN 30 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 420 AM CDT MON JUN 30 2014
AT 4 AM...THE MESOSCALE CONVECTIVE COMPLEX...WHICH BROUGHT THE
HEAVY RAIN TO NORTHEAST IOWA AND SOUTHWEST WISCONSIN AND POSSIBLE
TORNADO NEAR FENNIMORE WISCONSIN...EXTENDED FROM SOUTHERN LAKE
MICHIGAN TO WEST-CENTRAL ILLINOIS. STRONG 850 MB MOISTURE
TRANSPORT AHEAD OF AN 850 MB LOW ACROSS CENTRAL NEBRASKA IS
GENERATING CLUSTERS OF THUNDERSTORMS ACROSS EASTERN NEBRASKA AND
AND NORTHWEST IOWA. SOME ADDITIONAL THUNDERSTORMS ARE STARTING TO
DEVELOP ALONG ALONG A 900 TO 700 MB FRONTOGENETIC BAND ACROSS
SOUTHERN SOUTH DAKOTA. THIS IS IN RESPONSE TO A STRONG SHORTWAVE
TROUGH MOVING THROUGH EASTERN MONTANA AND WYOMING.
FOR THIS MORNING...EXPECT ROUNDS OF SHOWERS AND THUNDERSTORMS TO
DEVELOP ALONG A 900 TO 700 MB BAND OF FRONTOGENESIS ALONG THE
MINNESOTA AND IOWA BORDER. THIS IS STRENGTHENING WILL LIKELY KEEP
THE PRECIPITATION GOING DESPITE THE WEAKENING THAT IS TAKING
PLACE IN THE 925 AND 850 MB MOISTURE TRANSPORT. DEEP MOISTURE
GRADUALLY POOLS ALONG THIS BOUNDARY DURING THE MORNING. ALONG AND
SOUTH OF INTERSTATE 90...WARM CLOUD LAYER DEPTHS CLIMB FROM 3 TO
3.5 KM AT 30.12Z TO AROUND 4 KM AT 30.18Z. DURING THIS SAME TIME
PERIOD...PRECIPITABLE WATER VALUES CLIMB FROM AROUND 1.5 INCHES TO
2.0 INCHES IN THIS SAME AREA. AS A RESULT...THE SHOWERS AND
THUNDERSTORMS WILL BECOME VERY EFFICIENT RAIN PRODUCERS.
IN ADDITION...MEAN LAYER CAPES WILL REMAIN FROM 1500 TO
3500 J/KG. WHILE TYPICALLY THIS INSTABILITY WOULD WANE FROM THE
CONVECTION... SOUTHERLY WINDS WILL CONTINUE TO ADVECT THIS
INSTABILITY FROM AREAS THAT ARE CAPPED TO OUR SOUTH. IN
ADDITION...THE 0-6 KM SHEAR WILL BE FAVORABLE FOR THE DEVELOPMENT
OF ELEVATED SUPERCELLS. WITH A MAJORITY OF THIS SHEAR LOCATED
BELOW 3 KM...THERE WILL BE THE POTENTIAL FOR THESE SUPERCELLS TO
EVOLVED INTO LINES.
FOR THIS AFTERNOON...BOTH THE DETERMINISTIC AND MESO MODELS
SUGGEST THAT CYCLOGENESIS WILL DEVELOP ACROSS NORTHEAST IOWA AND
SOUTHWEST WISCONSIN THIS AFTERNOON. THIS IS RESPONSE TO THE 850 MB
LOW AND STRONG SHORT WAVE TROUGH COMING TOGETHER ACROSS THE AREA.
DUE TO CONVECTIVE FEEDBACK...BOTH THE GFS AND NAM ARE LIKELY TOO
STRONG WITH THEIR CYCLOGENESIS AND THIS GREATLY AFFECTS THEIR WIND
FIELDS. AS RESULT...LOOKED MORE AT THE WIND FIELDS IN THE MESO
MODELS. EVEN THESE MODELS...SHOW A RAPID STRENGTHENING IN THE 925
AND 850 MB MOISTURE TRANSPORT INTO THE REGION. THIS CAUSES THE
PRECIPITABLE WATER VALUES TO CLIMB TO AROUND 2.25 INCHES AND WARM
CLOUD DEPTHS TO INCREASE INTO THE 4 TO 4.5 INCH RANGE. WITH UPWARD
FORCING BEING ENHANCED FURTHER AS THE AREA ENTERS THE RIGHT
ENTRANCE REGION OF A 250 MB...EXPECT THE THREAT FOR HEAVY RAIN TO
CONTINUE.
AS WITH THIS MORNING...THE 0-6 KM SHEAR WILL REMAIN IN THE EXCESS
OF 45 KNOTS THIS AFTERNOON. IN ADDITION THE COMBINATION OF THE
STRONG CAP TO OUR SOUTH AND SOUTHERLY WINDS CONTINUING TO BRING
THIS 2500 TO 3500 J/KG ML CAPES INTO THE AREA WILL PROVIDE AMPLE
INSTABILITY TO KEEP THE THREAT FOR SUPERCELLS GOING DESPITE THE
PERSISTENT CONVECTION ACROSS THE AREA. WITH THE INCREASING WINDS
FIELDS DUE TO THE CYCLOGENESIS...THE 0-1 KM HELICITY AND BULK
SHEAR ALONG WITH LCL HEIGHTS WILL BECOME FAVORABLE FOR THE
POTENTIAL OF TORNADOES ACROSS THE EASTERN PORTIONS OF NORTHEAST
IOWA AND IN SOUTHWEST WISCONSIN DURING THE MID AND LATTER PARTS OF
THE AFTERNOON. THE DUBUQUE RAP HODOGRAPH FOR 29.22Z IS VERY
IMPRESSIVE.
FOR THIS EVENING...THE SEVERE WEATHER AND HEAVY RAIN THREAT WILL
COME QUICKLY TO AN END AS THE SHORT WAVE TROUGH MOVES QUICKLY
THROUGH THE REGION.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 420 AM CDT MON JUN 30 2014
ON TUESDAY...ANOTHER SHORT WAVE TROUGH WILL MOVE THROUGH THE AREA.
UNLIKE TODAY...THERE WILL BE MUCH LESS INSTABILITY /500 TO
1000 J/KG SURFACE CAPES/ AND LESS 0-6 KM SHEAR LESS THAN 35 KNOTS.
AS A RESULT...JUST EXPECTING SHOWERS AND A FEW SCATTERED
THUNDERSTORMS.
ON WEDNESDAY...ANOTHER SHORT WAVE TROUGH MOVES THROUGH THE AREA.
WITH ML CAPES GENERALLY LESS 500 J/KG...MOST OF THE DETERMINISTIC
MODELS HAVE THIS PERIOD DRY. THE LONE EXCEPTION IS THE ECMWF WHICH
GENERATES A FEW SHOWERS. SINCE IT IS SUMMER AND THE ECMWF
TYPICALLY DOES BETTER IN THIS TIME PERIOD...JUST KEPT A SLIGHT
CHANCE OF SHOWERS GOING.
FROM THE FOURTH OF JULY INTO THE UPCOMING WEEKEND...THE MODELS
CONTINUE TO STRUGGLE WITH THEIR TIMING AND LOCATION OF WAVES...SO
JUST STAYED WITH THE MODEL CONSENSUS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1226 AM CDT MON JUN 30 2014
SKIES HAVE CLEARED OUT IN THE WAKE OF THE SHOWERS THAT PASSED
THROUGH THE TAF SITES. ALTHOUGH A 5 KT OR SO SOUTHERLY BREEZE
EXISTS...MVFR/IFR BR HAS FORMED AT RST. WITH THE BREEZE STAYING
ABOUT THE SAME THROUGH THE REST OF THE NIGHT AND CLEAR SKIES
CONTINUING...HAVE MVFR/IFR BR AND LIFR CEILINGS AT RST WITH MVFR
BR AND POSSIBILITY OF AN LIFR CEILING AT LSE. THIS FOG AND LOW
CEILING POTENTIAL WILL QUICKLY END AFTER SUNRISE. ATTENTION THEN
SHIFTS TO THE WEST WHERE A WARM FRONT LIFTING NORTH THROUGH IOWA
IN THE MORNING SHOULD HELP SPARK MORE SHOWERS. THESE WILL IMPACT
RST AND LSE STARTING AT 14-15Z AND LASTING THROUGH THE REST OF THE
MORNING. THERE COULD EVEN BE SOME THUNDER...BUT ANTICIPATING THAT
TO BE ISOLATED AND THUS NO TS OR VCTS MENTION. BETTER CHANCES FOR
SHOWERS AND STORMS STILL EXIST IN THE AFTERNOON AS THE AIR SOUTH
OF THE WARM FRONT BECOMES MORE UNSTABLE. A PERIOD FROM 18-23Z FOR
THE TAF SITES OF VCTS AND SHOWER ACTIVITY REFLECTS THIS...AND
LATER FORECASTS MAY NEED TO INCLUDE A SHORTER PERIOD FOR
TSRA...ALONG WITH LOWERED VISIBILITIES AND CEILINGS. SKIES SHOULD
BEGIN TO CLEAR OUT AS A COLD FRONT PASSES EARLY IN THE EVENING
WITH WINDS SHIFTING WESTERLY IN ITS WAKE.
&&
.HYDROLOGY...
ISSUED AT 420 AM CDT MON JUN 30 2014
WITH DEEP WARM CLOUD DEPTHS...PRECIPITABLE WATER VALUES OF 2 TO
2.25 INCHES...SATURATED SOILS...AND ALREADY HIGH RIVERS AND
STREAM ACROSS NORTHEAST IOWA AND SOUTHEAST MINNESOTA...ISSUED A
FLASH FLOOD WATCH TODAY FOR THE POTENTIAL OF 1 TO 3 INCHES OF
ADDITIONAL RAIN. THERE WILL LIKELY BE LOCALLY HIGHER AMOUNTS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...FLASH FLOOD WATCH FROM 7 AM CDT THIS MORNING THROUGH THIS
EVENING FOR WIZ054-055-061.
MN...NONE.
IA...FLASH FLOOD WATCH FROM 7 AM CDT THIS MORNING THROUGH THIS
EVENING FOR IAZ008>011-018-019-029-030.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...AJ
HYDROLOGY...BOYNE
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1046 AM EDT MON JUN 30 2014
.SYNOPSIS...
THE REGION WILL BE IN BETWEEN THE BERMUDA HIGH AND A SLOWLY
APPROACHING COLD FRONT THROUGH WEDNESDAY NIGHT. THE FRONT WILL
MOVE SLOWLY ACROSS FROM THURSDAY INTO FRIDAY. POTENTIAL LOW
PRESSURE MOVING NORTH ALONG THE EAST COAST SHOULD PASS SOUTH OF
THE REGION FRIDAY INTO FRIDAY NIGHT. HIGH PRESSURE WILL THEN BUILD
IN FOR THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MID AND HIGH LEVEL CLOUDS CONTINUE TO SPREAD ACROSS WESTERN
SECTIONS OF THE CWA. SPOTTY SHOWERS APPROACH FROM THE WEST. HAVE
INCLUDED ISO SHOWER MENTION FOR LOWER HUDSON FOR MID DAY...WITH
CONTINUING MENTION OF 20 TSTM POP FOR ORANGE COUNTY FOR LATE AFTN
AS A DISSIPATING STORM COULD MAKE IT INTO THAT PART OF THE
FORECAST AREA.
BROKEN CLOUDS...MENTIONED ABOVE...PASS ACROSS THE REGION THIS
MORNING AND THEN THIN THIS AFTERNOON.
HIGH TEMPS WILL BE NEAR 80 FOR THE COASTAL REGION IN A REPEAT OF
SUNDAYS SEA BREEZE PATTERN. AWAY FROM THE COAST...MID 80S
EXPECTED...THOUGH THIS DEPENDS SOMEWHAT ON THE AMOUNT OF CLOUD
COVER.
THERE IS A MODERATE RISK OF RIP CURRENTS AT ATLANTIC BEACHES TODAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
DEW POINTS CONTINUE A SLOW INCREASE THROUGH THE PERIOD AS
SOUTHERLY FLOW GRADUALLY INCREASES.
HAVE REMOVED THE FOG FROM THE FORECAST FOR TONIGHT. THINKING IS
THAT WE MAY FORM MORE OF A LOW STRATUS CONDITION ALONG THE COAST.
THIS BASED ON LATEST RAP SOUNDINGS AND MOS GUIDANCE. WITH WATER
TEMPS AROUND 70...ADVECTION FOG DOES NOT SEEM LIKELY.
ON TUESDAY...TEMPS CONTINUE TO SLOWLY WARM AND HAVE GONE WITH THE
WARMER GFS MOS.
CONTINUED THE 20-30 POP TO THE NW OF NYC WITH SBCAPE IN THE NAM
NEARING 1000 J/KG.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
ACTIVE WEATHER POSSIBLE LATE IN THE WEEK.
EAST COAST RIDGE GIVES WAY TO APPROACHING TROUGH MID TO LATE WEEK.
SFC HIGH PRESSURE OVER THE ATLANTIC DEPARTS AS THE SLOW MOVING COLD
FRONT APPROACHES THE AREA.
WARM AND HUMID WEATHER IS EXPECTED...WITH MAINLY DIURNALLY DRIVEN
SHOWERS AND THUNDERSTORMS THROUGH WEDNESDAY...WITH HIGHEST POPS
ACROSS THE INTERIOR. THEN POPS INCREASE THURSDAY...THURSDAY NIGHT
AND FRIDAY AS THE FRONT NEARS. PLENTY OF MOISTURE WILL BE TAPPED AS
TROPICAL LOW OFF THE SOUTHEAST COAST LOOKS TO GET PICKED UP BY
SOUTHERLY STEERING WINDS AHEAD OF THE TROUGH.
ECMWF...GFS SEEM TO BE IN REASONABLE AGREEMENT ON THE TRACK OF THE
FRONT...AND TROPICAL LOW. HEAVY RAIN IS POSSIBLE LATER
THURSDAY...THURSDAY NIGHT AND POSSIBLY INTO FRIDAY.
THE TROUGH MOVES ACROSS THE NORTHEAST WITH A RIDGE BUILDING IN
BEHIND FOR A GOOD PORTION OF THE WEEKEND.
WARM TEMPS ARE EXPECTED AS PERSISTENT SOUTHERLY FLOW PREVAILS. ABOVE
NORMAL READINGS CAN BE EXPECTED TUESDAY NIGHT THROUGH WEDNESDAY
NIGHT...WITH CLOSER TO NORMAL READINGS THEREAFTER. HOTTEST DAY THIS
TIME FRAME APPEARS TO BE WEDNESDAY WITH READINGS IN THE 80S TO
AROUND 90.
INCREASING CLOUDS AND HIGHER COVERAGE OF SHOWERS/TSTMS THURSDAY AND
FRIDAY WILL KNOCK A FEW DEGREES OFF DAYTIME TEMPS. PLENTY OF
SUNSHINE OVER THE WEEKEND SHOULD RESULT IN NEAR NORMAL READINGS BEHIND
THE LOW/FRONT.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
HIGH PRESSURE OFF THE MID ATLANTIC COAST WILL DRIFT SLOWLY
EASTWARD...WITH CONTINUED S-SW FLOW.
VFR THROUGH THE DAY TODAY.
AFTERNOON SEA BREEZES WILL INCREASE WINDS TO 10 TO 15 KT AT THE
COASTAL TERMINALS. GUSTS CLOSE TO 20 KT ARE POSSIBLE FROM LATE
DAY UNTIL AT LEAST SUNSET AT KJFK/KLGA/KISP...AND COULD LAST
LONGER INTO THE EVENING. WINDS DIMINISH THEREAFTER...AND EXPECT
A LITTLE MORE WIDESPREAD LOW-END MVFR OR IFR CONDS LATE TONIGHT.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS
CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: GUSTY S WINDS COULD LAST LONGER INTO THE
EVENING THAN FCST.
KLGA FCSTER COMMENTS: GUSTY S WINDS COULD LAST LONGER INTO THE
EVENING THAN FCST.
KEWR FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH
IMPLIES SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.
KHPN FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.
KISP FCSTER COMMENTS: GUSTY S WINDS COULD LAST LONGER INTO THE
EVENING THAN FCST.
.OUTLOOK FOR 12Z TUE THROUGH FRI...
.TUE...CHANCE OF AN AFTERNOON TSTM WITH BRIEF MVFR OR LOWER CONDS
AND/OR AND GUSTY WINDS AT KSWF. FOG AND LOW STRATUS WITH MVFR OR
LOWER CONDS LIKELY LATE AT NIGHT.
.WED...FOG AND LOW STRATUS WITH MVFR OR LOWER CONDS BURNING OFF
EARLY IN THE MORNING. CHANCE OF SHOWERS/TSTMS WITH MVFR OR LOWER
CONDS IN THE AFTERNOON MAINLY FROM NYC METRO NORTH AND
WEST...SPREADING TO THE COAST IN THE EVENING.
.THU-FRI...NUMEROUS SHOWERS/TSTMS...WITH IFR CONDS IN HEAVY
RAIN POSSIBLE.
&&
.MARINE...
WINDS AND WAVES FORECAST ON TRACK FOR TODAY.
SEA BREEZES AGAIN LATE THIS AFTN WILL RESULT IN A PERIOD OF 15 KT
WITH GUST UP TO 20 KT ON THE WATERS. HIGHEST WOULD BE IN SOUTH OF
THE ROCKAWAYS.
SEA BREEZES ARE STRONGER YET TUESDAY AFTN WITH GUSTS UP TO 25 KT
AND THE POTENTIAL FOR SCA CONDITIONS...ESPECIALLY ON THE OCEAN.
PERSISTENT SOUTHERLY FLOW TUESDAY NIGHT WILL DIMINISH WEDNESDAY AND
THURSDAY AS A COLD FRONT APPROACHES AND THE PRESSURE GRADIENT
WEAKENS. WITH THE FRONT SLOWLY MOVING ACROSS THE WATERS EARLY
FRIDAY...WINDS REMAIN RATHER LIGHT. NEED TO MONITOR EVENTUAL
PROGRESSION OF A TROPICAL LOW LATE FRIDAY AS IT POSSIBLY APPROACHES
THE WATERS FROM THE SOUTH.
OCEAN SEAS OF 3 TO 6 FEET TUESDAY NIGHT WILL SUBSIDE AS THE
SOUTHERLY WINDS DIMINISH WEDNESDAY THROUGH THURSDAY. AT THIS
TIME...SEAS SHOULD REMAIN BELOW 5 FT MOST OF FRIDAY...BUT WOULD
LIKELY BUILD LATE IN THE DAY DEPENDING ON TRACK AND STRENGTH OF LOW
PRESSURE TO THE SOUTH.
&&
.HYDROLOGY...
NO SIGNIFICANT PRECIPITATION IS EXPECTED INTO TUESDAY.
THERE IS THE POTENTIAL FOR SIGNIFICANT RAINFALL TOWARD THE END OF
THE WEEK...THURSDAY AND THURSDAY NIGHT. AT THIS TIME THERE IS TOO
MUCH UNCERTAINTY TO SPECIFY EXACT AMOUNTS OR SPECIFIC THREATS.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TONGUE/PW
NEAR TERM...SEARS/TONGUE
SHORT TERM...TONGUE
LONG TERM...PW
AVIATION...BC
MARINE...TONGUE/PW
HYDROLOGY...TONGUE/PW
AREA FORECAST DISCUSSION
NWS ALBANY NY
746 AM EDT MON JUN 30 2014
.SYNOPSIS...
HIGH PRESSURE OFFSHORE WILL TRANSFORM INTO A BERMUDA HIGH. A WEAK
WARM FRONT CROSSING THE REGION TODAY WILL BRING SOME WIDELY
SCATTERED SHOWERS AND MAYBE A THUNDERSTORM. IT WILL THEN TURN MORE
HUMID AND HOT MID WEEK WITH SCATTERED MAINLY AFTERNOON
THUNDERSTORMS. WHILE MOST OF THE TIME WILL BE RAINFREE ANY
THUNDERSTORM THAT DEVELOPS COULD CONTAIN HEAVY RAINFALL AND GUSTY
WINDS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATED FORECAST TO ALIGN WITH SHRA ACTIVITY WORKINGA CROSS CWA
THIS MORNING.
THE LINE OF SHOWERS WAS THE RESULT OF A SECONDARY WARM
FRONT...REALLY MORE LIKE A DEWPOINT DISCONTINUITY LINE OVER CENTRAL
NEW YORK. DEWPOINTS ON THE EAST SIDE OF THIS BOUNDARY WERE STILL
GENERALLY IN THE 50S...AND IN SOME CASES...FALLING. TO THE WEST OF
THIS BOUNDARY...THEY HAD RISEN WELL INTO THE 60S.
THE 08Z HRRR STILL INDICATED SHOWER AND AFTERNOON THUNDERSTORM
ACTIVITY VERY RANDOMLY DISTRIBUTED OVER THE REGION...MAINLY WEST OF
THE HUDSON VALLEY...WHERE INSTABILITY LOOKS TO BE A LITTLE
BETTER...AS OPPOSED TO FURTHER EAST. UP TO 1000 J/KG OF INSTABILITY
IS POSSIBLE WEST OF THE HUDSON VALLEY. WE HAVE WE PLACED 40 POPS TO
THE NW OF THE CAPITAL REGION...30 CAPITAL REGION...ONLY 20 (LATE)
FURTHER SOUTH AND EAST.
DUE TO A LITTLE MORE IN THE WAY OF CLOUDS AND THE FRONT
NEARBY...TEMPERATURES TODAY COULD ACTUALLY BE A POINT OR TWO LOWER
THAN YESTERDAY BUT HUMIDITY WILL BEGIN TO CREEP UPWARD.
A SOUTH WIND WILL PREVAIL 5 TO 15 MPH TODAY. LOOK FOR HIGHS IN THE
MID 80S MOST VALLEY LOCATIONS...CLOSER TO 80 HIGHER TERRAIN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
ANY THUNDERSTORM ACTIVITY SHOULD DWINDLE THIS EVENING WE LOOSE THE
HEATING. ALSO...THE AFOREMENTIONED WARM FRONT WILL LIKELY HAVE MOVED
TO OUR EAST BY THEN.
WE WILL ULTIMATELY BE LEFT WITH A MUGGY SOMEWHAT HAZY NIGHT. A SOUTH
WIND WILL CONTINUE 5-10 MPH. OVERNIGHT LOWS WILL BE IN THE MID TO
UPPER 60S.
TUESDAY LOOKS TO BE A HOT ONE. BERMUDA HIGH OFFSHORE WILL PUMP A
SOUTHWEST FLOW OUR WAY. THIS FLOW WILL SEND H850 TEMPERATURES TO
NEAR 20C ACROSS MUCH OF OUR REGION. DEWPOINTS WILL CLIMB WELL INTO
THE 60S. WITH A GOOD DEAL OF HAZY SUNSHINE...THIS WILL TRANSLATE TO
SURFACE TEMPERATURES HITTING CLOSE TO 90 DEGREES IN VALLEY
LOCATIONS...LOWER TO MID 80S HIGHER TERRAIN.
THE DAY WILL START OUT MAINLY RAINFREE. HOWEVER...INSTABILITY LOOKS
TO RAMP UP TO WELL OVER 1500 J/KG DURING THE AFTERNOON. THIS COULD
BE ENOUGH INSTABILITY WHEN COMBINED WITH A VERY WEAK DISTURBANCE
SPARKED BY AN UPSTREAM TROUGH...TO PRODUCE WIDELY SCATTERED
THUNDERSTORMS DURING THE AFTERNOON. WHILE COVERAGE OF THE
THUNDERSTORMS LOOKS WIDELY SCATTERED...ANY THUNDERSTORM THAT DOES
FORM AS A SLIGHT CHANCE OF PRODUCING GUSTY WINDS AND HEAVY
RAINFALL...AND COULD PULSE BRIEFLY TO SEVERE LIMITS...MAINLY WIND
DAMAGE.
THUNDERSTORMS WILL DIMINISH AGAIN TUESDAY NIGHT AS ONCE AGAIN IT
WILL BE QUITE MUGGY. OVERNIGHT LOWS WILL LIKELY STAY AT OR ABOVE 70
IN THE HUDSON VALLEY FROM THE CAPITAL REGION SOUTHWARD...LOWER TO
MID 60S HIGHER TERRAIN.
WEDNESDAY WILL BE HOT AGAIN. THIS TIME HOWEVER...A COLD FRONT WILL
BE APPROACHING FROM THE NORTHWEST. EITHER THE FRONT...OR MORE LIKELY
A PRE-FRONTAL TROUGH LOOKS TO BE FOCUS FOR ANY CONVECTION THAT
DEVELOPS MAINLY DURING THE AFTERNOON. WE HAVE INCREASED POPS TO 50
DURING THE AFTERNOON.
DEPENDING ON HOW MUCH SUNSHINE WE RECEIVE TEMPERATURES COULD ONCE
AGAIN HIT 90 OR A LITTLE HIGHER ACROSS THE HUDSON VALLEY...MID OR
UPPER 80S ELSEWHERE ACROSS THE REGION. WE EXPECT MORE SUNSHINE THAN
CLOUDS...AT LEAST THROUGH THE TIME OF THE PEAK HEATING.
THE COLD FRONT (OR FRONTS) WILL SLOWLY MOVE THROUGH WEDNESDAY NIGHT
SO SHOWERS AND THUNDERSTORM ACTIVITY SHOULD CONTINUE. OVERNIGHT LOWS
WILL COOL TO THE 50S ACROSS THE ADIRONDACKS PARK WHERE THE FRONT IS
FORECAST TO MOVE THROUGH. FURTHER SOUTH...LOWS WILL GENERALLY
REMAIN IN THE 60S.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
MOST OF THE ATTENTION THIS UPCOMING LONG TERM PERIOD WILL BE WHAT IF
ANY IMPACTS WILL OCCUR ACROSS THE CWFA FROM THE DEVELOPING TROPICAL
ENTITY OFF THE SOUTHEAST COAST. LATEST GLOBAL MODELS CONTINUE TO
SUGGEST THIS TROPICAL ENTITY WILL TRACK OFF THE ATLANTIC COAST.
HOWEVER...THIS IN TURN MAY HAVE AN IMPACT WITH A SLOWER COLD FRONTAL
PASSAGE FORECAST ON THURSDAY. FURTHERMORE...WHILE STILL QUITE EARLY
IN THE FORECAST PROCESS...A POTENTIAL "PRE" EVENT MAY UNFOLD FOR
PORTIONS OF OUR REGION. GIVEN THE UNCERTAINTY...WE WILL HOLD ONTO
AND EXPAND A BIT THE POPS/WX GRIDS THROUGH MOST OF THURSDAY INTO
THURSDAY NIGHT. GUIDANCE NUMBERS DO LOOK A LITTLE HIGH GIVEN THE
EXPECT CLOUD COVER AND THE CHANCE FOR PRECIP AS WE WILL SHADE
SLIGHTLY COOLER PER THE WPC/ECMWF NUMBERS.
THEREAFTER...A BROAD ANTICYCLONIC FLOW /SURFACE HIGH/ SLOWLY BUILDS
ACROSS THE REGION INDEPENDENCE DAY AND INTO THE HOLIDAY WEEKEND.
THIS COULD BRING ABOUT THE FIFTH CONSECUTIVE DRY WEEKEND TO THE
REGION AS SUBSIDENCE INCREASES IN THE WAKE OF THE COASTAL EVENT AND
RISING HEIGHTS ALOFT. AS SUNSHINE INCREASES...SO TOO WILL BE THE
SURFACE TEMPERATURES WITH MAINLY LOWER HALF OF THE 80S FOR AFTERNOON
HIGHS AND OVERNIGHT LOWS INTO THE 50S AND LOWER 60S.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
HIGH AND MID LEVEL CLOUDS CONTINUE TO SLOW INVADE THE REGION FROM
THE WEST. REGIONAL RADAR VIEW DEPICTS A BKN LINE OF SHOWERS
EXTENDING FROM THE ADIRONDACKS...WESTERN MOHAWK VALLEY INTO THE
SCHOHARIE VALLEY. EXPERIMENTAL FORECAST RADAR REFLECTIVITIES
SUGGEST THIS LINE WILL APPROACH THE HUDSON VALLEY THROUGH THE MID
MORNING HOURS. HOWEVER...CONFIDENCE IN DIRECTLY IMPACTING THE TAF
LOCATIONS REMAINS IN A `VCSH` THRESHOLD. OTHERWISE...A VFR DAY
UNFOLDING.
TONIGHT...INCREASING LOW LEVEL MOISTURE WILL LIKELY RESULT IN AN
INCREASE OF BR/HZ AND HAVE TRENDED THESE INTO THE TAFS TONIGHT.
THESE REDUCTIONS COULD GET DOWN TO MVFR AND POSSIBLE IFR FLIGHT
CONDITIONS OVERNIGHT.
LIGHT SOUTHERLY WINDS AT 10KTS OR LESS EXPECTED.
OUTLOOK...
TUESDAY NIGHT: LOW OPERATIONAL IMPACT.BREEZY SLIGHT CHANCE OF
SHRA...TSRA.
WEDNESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
WEDNESDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
THURSDAY: HIGH OPERATIONAL IMPACT. LIKELY SHRA...TSRA.
THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
INDEPENDENCE DAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
MOST AREAS DID NOT SEE A FULL RECOVERY OVERNIGHT DUE TO A BREEZE AND
HIGH CLOUDS. HOWEVER...RH VALUES WILL REMAIN SLIGHTLY ELEVATED
THROUGHOUT THE DAY...BOTTOMING OUT AROUND 50 PERCENT. THERE WILL BE
MORE CLOUDS THAN YESTERDAY ALONG WITH WIDELY SCATTERED SHOWERS AND
MAYBE AN AFTERNOON THUNDERSTORM AROUND BUT MOST AREAS WILL LIKELY
NOT PICK UP A QUARTER OF AN INCH.
A NEARLY FULL RECOVERY LIKELY TONIGHT AS IT WILL BE MORE HUMID AND
THE BREEZE ONLY SLIGHT.
HOT TUESDAY WITH MOST VALLEY AREAS APPROACHING OR EVEN ECLIPSING 90
DEGREES. AFTERNOON RH VALUES WILL AROUND 50 PERCENT ONCE MORE.
A SOUTH TO SOUTHWEST WIND WILL INCREASE TO 10-15 MPH...WITH SOME
AFTERNOON GUSTS TO 25 MPH ON TUESDAY.
AFTERNOON THUNDERSTORMS ARE POSSIBLE ONCE MORE ON...MAINLY WEST OF
THE HUDSON VALLEY ON TUESDAY.
MORE THUNDERSTORMS POSSIBLE ALONG WITH HOT AND HUMID WEATHER FOR
WEDNESDAY. HOWEVER...A COLD FRONT WILL LIKELY WORK THROUGH WEDNESDAY
NIGHT...STALLING JUST SOUTH OF OUR REGION ON THURSDAY.
&&
.HYDROLOGY...
NO HYDRO PROBLEMS EXPECTED TODAY.
THERE WILL LIGHT SHOWERS AROUND THIS MORNING AND THE POSSIBILITY OF
WIDELY SCATTERED AFTERNOON THUNDERSTORMS. THESE DO NOT LOOK TO
PRODUCE AVERAGE BASIN RAINFALLS OF A QUARTER OF AN INCH OR MORE.
MORE ROBUST THUNDERSTORMS ARE POSSIBLE TUESDAY...MAINLY WEST OF THE
HUDSON VALLEY. SOME OF THESE COULD PRODUCE LOCALIZED DOWNPOURS AS
PWATS LOOK TO RAMP TO NEARLY 2 INCHES. ANY OF THESE THUNDERSTORMS
COULD PRODUCE PONDING OF WATER ON ROADWAYS AND AREAS OF POOR
DRAINAGE.
EVEN SO...AVERAGE BASIN RAINFALL ON TUESDAY WILL LIKELY REMAIN AT OR
BELOW A QUARTER INCH. MAJOR RIVERS WILL LIKELY SEE ONLY MINOR RISES
IF THAT.
BY WEDNESDAY...AS COLD FRONT PLOWS INTO THE TROPICAL
AIR...THUNDERSTORMS COULD BE A BIT MORE NUMEROUS AND AGAIN CONTAIN
TORRENTIAL DOWNPOURS LEADING TO MINOR FLOODING.
BY THURSDAY...THIS FRONT LOOKS TO STALL JUST SOUTH OF OUR REGION. AT
THE SAME TIME...SOME SORT OF TROPICAL SYSTEM LOOKS TO SPIN UP ALONG
THE EASTERN SEABOARD TO OUR SOUTH. WHILE ALL MODELS HAVE THE ACTUAL
ENTITY MISSING OUR REGION...A PREDECESSOR RAINFALL EVENT (PRE) IS
FORECAST BY ALL MODELS TO FORM ALONG THIS BOUNDARY. THIS QUESTION IS
HOW FAR NORTH THIS PRE WILL GET WHICH COULD PRODUCE SIGNIFICANT
WIDESPREAD RAINFALL THURSDAY.
STAY TUNED.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV/OKEEFE
SHORT TERM...HWJIV
LONG TERM...BGM
AVIATION...BGM
FIRE WEATHER...HWJIV
HYDROLOGY...HWJIV
AREA FORECAST DISCUSSION
NWS ALBANY NY
650 AM EDT MON JUN 30 2014
.SYNOPSIS...
HIGH PRESSURE OFFSHORE WILL TRANSFORM INTO A BERMUDA HIGH. A WEAK
WARM FRONT CROSSING THE REGION TODAY WILL BRING SOME WIDELY
SCATTERED SHOWERS AND MAYBE A THUNDERSTORM. IT WILL THEN TURN MORE
HUMID AND HOT MID WEEK WITH SCATTERED MAINLY AFTERNOON
THUNDERSTORMS. WHILE MOST OF THE TIME WILL BE RAINFREE ANY
THUNDERSTORM THAT DEVELOPS COULD CONTAIN HEAVY RAINFALL AND GUSTY
WINDS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 630 AM EDT...SHOWERS STILL WORKING FROM WEST TO EAST ACROSS
THE MOHAWK VALLEY AND ABOUT TO MOVE INTO THE SCHOHARIE VALLEY. THEY
HAVE WEAKENED A LITTLE MORE BUT SOME SHOWERS STILL LOOK TO MAKE IT
INTO THE HUDSON VALLEY AND EVEN POINTS EASTWARD (ISOLATED).
TEMPERATURES WERE VERY MILD IN THE 60S...BUT DEWPOINTS WERE IN THE
50S SO NOT THAT MUGGY OUT.
FOR THIS UPDATE...ONLY VERY MINOR TWEAKING OF THE HOURLY GRIDS
(INCLUDING POP AND WEATHER).
THE LINE OF SHOWERS WAS THE RESULT OF A SECONDARY WARM
FRONT...REALLY MORE LIKE A DEWPOINT DISCONTINUITY LINE OVER CENTRAL
NEW YORK. DEWPOINTS ON THE EAST SIDE OF THIS BOUNDARY WERE STILL
GENERALLY IN THE 50S...AND IN SOME CASES...FALLING. TO THE WEST OF
THIS BOUNDARY...THEY HAD RISEN WELL INTO THE 60S.
THE 08Z HRRR STILL INDICATED SHOWER AND AFTERNOON THUNDERSTORM
ACTIVITY VERY RANDOMLY DISTRIBUTED OVER THE REGION...MAINLY WEST OF
THE HUDSON VALLEY...WHERE INSTABILITY LOOKS TO BE A LITTLE
BETTER...AS OPPOSED TO FURTHER EAST. UP TO 1000 J/KG OF INSTABILITY
IS POSSIBLE WEST OF THE HUDSON VALLEY. WE HAVE WE PLACED 40 POPS TO
THE NW OF THE CAPITAL REGION...30 CAPITAL REGION...ONLY 20 (LATE)
FURTHER SOUTH AND EAST.
DUE TO A LITTLE MORE IN THE WAY OF CLOUDS AND THE FRONT
NEARBY...TEMPERATURES TODAY COULD ACTUALLY BE A POINT OR TWO LOWER
THAN YESTERDAY BUT HUMIDITY WILL BEGIN TO CREEP UPWARD.
A SOUTH WIND WILL PREVAIL 5 TO 15 MPH TODAY. LOOK FOR HIGHS IN THE
MID 80S MOST VALLEY LOCATIONS...CLOSER TO 80 HIGHER TERRAIN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
ANY THUNDERSTORM ACTIVITY SHOULD DWINDLE THIS EVENING WE LOOSE THE
HEATING. ALSO...THE AFOREMENTIONED WARM FRONT WILL LIKELY HAVE MOVED
TO OUR EAST BY THEN.
WE WILL ULTIMATELY BE LEFT WITH A MUGGY SOMEWHAT HAZY NIGHT. A SOUTH
WIND WILL CONTINUE 5-10 MPH. OVERNIGHT LOWS WILL BE IN THE MID TO
UPPER 60S.
TUESDAY LOOKS TO BE A HOT ONE. BERMUDA HIGH OFFSHORE WILL PUMP A
SOUTHWEST FLOW OUR WAY. THIS FLOW WILL SEND H850 TEMPERATURES TO
NEAR 20C ACROSS MUCH OF OUR REGION. DEWPOINTS WILL CLIMB WELL INTO
THE 60S. WITH A GOOD DEAL OF HAZY SUNSHINE...THIS WILL TRANSLATE TO
SURFACE TEMPERATURES HITTING CLOSE TO 90 DEGREES IN VALLEY
LOCATIONS...LOWER TO MID 80S HIGHER TERRAIN.
THE DAY WILL START OUT MAINLY RAINFREE. HOWEVER...INSTABILITY LOOKS
TO RAMP UP TO WELL OVER 1500 J/KG DURING THE AFTERNOON. THIS COULD
BE ENOUGH INSTABILITY WHEN COMBINED WITH A VERY WEAK DISTURBANCE
SPARKED BY AN UPSTREAM TROUGH...TO PRODUCE WIDELY SCATTERED
THUNDERSTORMS DURING THE AFTERNOON. WHILE COVERAGE OF THE
THUNDERSTORMS LOOKS WIDELY SCATTERED...ANY THUNDERSTORM THAT DOES
FORM AS A SLIGHT CHANCE OF PRODUCING GUSTY WINDS AND HEAVY
RAINFALL...AND COULD PULSE BRIEFLY TO SEVERE LIMITS...MAINLY WIND
DAMAGE.
THUNDERSTORMS WILL DIMINISH AGAIN TUESDAY NIGHT AS ONCE AGAIN IT
WILL BE QUITE MUGGY. OVERNIGHT LOWS WILL LIKELY STAY AT OR ABOVE 70
IN THE HUDSON VALLEY FROM THE CAPITAL REGION SOUTHWARD...LOWER TO
MID 60S HIGHER TERRAIN.
WEDNESDAY WILL BE HOT AGAIN. THIS TIME HOWEVER...A COLD FRONT WILL
BE APPROACHING FROM THE NORTHWEST. EITHER THE FRONT...OR MORE LIKELY
A PRE-FRONTAL TROUGH LOOKS TO BE FOCUS FOR ANY CONVECTION THAT
DEVELOPS MAINLY DURING THE AFTERNOON. WE HAVE INCREASED POPS TO 50
DURING THE AFTERNOON.
DEPENDING ON HOW MUCH SUNSHINE WE RECEIVE TEMPERATURES COULD ONCE
AGAIN HIT 90 OR A LITTLE HIGHER ACROSS THE HUDSON VALLEY...MID OR
UPPER 80S ELSEWHERE ACROSS THE REGION. WE EXPECT MORE SUNSHINE THAN
CLOUDS...AT LEAST THROUGH THE TIME OF THE PEAK HEATING.
THE COLD FRONT (OR FRONTS) WILL SLOWLY MOVE THROUGH WEDNESDAY NIGHT
SO SHOWERS AND THUNDERSTORM ACTIVITY SHOULD CONTINUE. OVERNIGHT LOWS
WILL COOL TO THE 50S ACROSS THE ADIRONDACKS PARK WHERE THE FRONT IS
FORECAST TO MOVE THROUGH. FURTHER SOUTH...LOWS WILL GENERALLY
REMAIN IN THE 60S.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
MOST OF THE ATTENTION THIS UPCOMING LONG TERM PERIOD WILL BE WHAT IF
ANY IMPACTS WILL OCCUR ACROSS THE CWFA FROM THE DEVELOPING TROPICAL
ENTITY OFF THE SOUTHEAST COAST. LATEST GLOBAL MODELS CONTINUE TO
SUGGEST THIS TROPICAL ENTITY WILL TRACK OFF THE ATLANTIC COAST.
HOWEVER...THIS IN TURN MAY HAVE AN IMPACT WITH A SLOWER COLD FRONTAL
PASSAGE FORECAST ON THURSDAY. FURTHERMORE...WHILE STILL QUITE EARLY
IN THE FORECAST PROCESS...A POTENTIAL "PRE" EVENT MAY UNFOLD FOR
PORTIONS OF OUR REGION. GIVEN THE UNCERTAINTY...WE WILL HOLD ONTO
AND EXPAND A BIT THE POPS/WX GRIDS THROUGH MOST OF THURSDAY INTO
THURSDAY NIGHT. GUIDANCE NUMBERS DO LOOK A LITTLE HIGH GIVEN THE
EXPECT CLOUD COVER AND THE CHANCE FOR PRECIP AS WE WILL SHADE
SLIGHTLY COOLER PER THE WPC/ECMWF NUMBERS.
THEREAFTER...A BROAD ANTICYCLONIC FLOW /SURFACE HIGH/ SLOWLY BUILDS
ACROSS THE REGION INDEPENDENCE DAY AND INTO THE HOLIDAY WEEKEND.
THIS COULD BRING ABOUT THE FIFTH CONSECUTIVE DRY WEEKEND TO THE
REGION AS SUBSIDENCE INCREASES IN THE WAKE OF THE COASTAL EVENT AND
RISING HEIGHTS ALOFT. AS SUNSHINE INCREASES...SO TOO WILL BE THE
SURFACE TEMPERATURES WITH MAINLY LOWER HALF OF THE 80S FOR AFTERNOON
HIGHS AND OVERNIGHT LOWS INTO THE 50S AND LOWER 60S.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
HIGH AND MID LEVEL CLOUDS CONTINUE TO SLOW INVADE THE REGION FROM
THE WEST. REGIONAL RADAR VIEW DEPICTS A BKN LINE OF SHOWERS
EXTENDING FROM THE ADIRONDACKS...WESTERN MOHAWK VALLEY INTO THE
SCHOHARIE VALLEY. EXPERIMENTAL FORECAST RADAR REFLECTIVITIES
SUGGEST THIS LINE WILL APPROACH THE HUDSON VALLEY THROUGH THE MID
MORNING HOURS. HOWEVER...CONFIDENCE IN DIRECTLY IMPACTING THE TAF
LOCATIONS REMAINS IN A `VCSH` THRESHOLD. OTHERWISE...A VFR DAY
UNFOLDING.
TONIGHT...INCREASING LOW LEVEL MOISTURE WILL LIKELY RESULT IN AN
INCREASE OF BR/HZ AND HAVE TRENDED THESE INTO THE TAFS TONIGHT.
THESE REDUCTIONS COULD GET DOWN TO MVFR AND POSSIBLE IFR FLIGHT
CONDITIONS OVERNIGHT.
LIGHT SOUTHERLY WINDS AT 10KTS OR LESS EXPECTED.
OUTLOOK...
TUESDAY NIGHT: LOW OPERATIONAL IMPACT.BREEZY SLIGHT CHANCE OF
SHRA...TSRA.
WEDNESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
WEDNESDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
THURSDAY: HIGH OPERATIONAL IMPACT. LIKELY SHRA...TSRA.
THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
INDEPENDENCE DAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
MOST AREAS DID NOT SEE A FULL RECOVERY OVERNIGHT DUE TO A BREEZE AND
HIGH CLOUDS. HOWEVER...RH VALUES WILL REMAIN SLIGHTLY ELEVATED
THROUGHOUT THE DAY...BOTTOMING OUT AROUND 50 PERCENT. THERE WILL BE
MORE CLOUDS THAN YESTERDAY ALONG WITH WIDELY SCATTERED SHOWERS AND
MAYBE AN AFTERNOON THUNDERSTORM AROUND BUT MOST AREAS WILL LIKELY
NOT PICK UP A QUARTER OF AN INCH.
A NEARLY FULL RECOVERY LIKELY TONIGHT AS IT WILL BE MORE HUMID AND
THE BREEZE ONLY SLIGHT.
HOT TUESDAY WITH MOST VALLEY AREAS APPROACHING OR EVEN ECLIPSING 90
DEGREES. AFTERNOON RH VALUES WILL AROUND 50 PERCENT ONCE MORE.
A SOUTH TO SOUTHWEST WIND WILL INCREASE TO 10-15 MPH...WITH SOME
AFTERNOON GUSTS TO 25 MPH ON TUESDAY.
AFTERNOON THUNDERSTORMS ARE POSSIBLE ONCE MORE ON...MAINLY WEST OF
THE HUDSON VALLEY ON TUESDAY.
MORE THUNDERSTORMS POSSIBLE ALONG WITH HOT AND HUMID WEATHER FOR
WEDNESDAY. HOWEVER...A COLD FRONT WILL LIKELY WORK THROUGH WEDNESDAY
NIGHT...STALLING JUST SOUTH OF OUR REGION ON THURSDAY.
&&
.HYDROLOGY...
NO HYDRO PROBLEMS EXPECTED TODAY.
THERE WILL LIGHT SHOWERS AROUND THIS MORNING AND THE POSSIBILITY OF
WIDELY SCATTERED AFTERNOON THUNDERSTORMS. THESE DO NOT LOOK TO
PRODUCE AVERAGE BASIN RAINFALLS OF A QUARTER OF AN INCH OR MORE.
MORE ROBUST THUNDERSTORMS ARE POSSIBLE TUESDAY...MAINLY WEST OF THE
HUDSON VALLEY. SOME OF THESE COULD PRODUCE LOCALIZED DOWNPOURS AS
PWATS LOOK TO RAMP TO NEARLY 2 INCHES. ANY OF THESE THUNDERSTORMS
COULD PRODUCE PONDING OF WATER ON ROADWAYS AND AREAS OF POOR
DRAINAGE.
EVEN SO...AVERAGE BASIN RAINFALL ON TUESDAY WILL LIKELY REMAIN AT OR
BELOW A QUARTER INCH. MAJOR RIVERS WILL LIKELY SEE ONLY MINOR RISES
IF THAT.
BY WEDNESDAY...AS COLD FRONT PLOWS INTO THE TROPICAL
AIR...THUNDERSTORMS COULD BE A BIT MORE NUMEROUS AND AGAIN CONTAIN
TORRENTIAL DOWNPOURS LEADING TO MINOR FLOODING.
BY THURSDAY...THIS FRONT LOOKS TO STALL JUST SOUTH OF OUR REGION. AT
THE SAME TIME...SOME SORT OF TROPICAL SYSTEM LOOKS TO SPIN UP ALONG
THE EASTERN SEABOARD TO OUR SOUTH. WHILE ALL MODELS HAVE THE ACTUAL
ENTITY MISSING OUR REGION...A PREDECESSOR RAINFALL EVENT (PRE) IS
FORECAST BY ALL MODELS TO FORM ALONG THIS BOUNDARY. THIS QUESTION IS
HOW FAR NORTH THIS PRE WILL GET WHICH COULD PRODUCE SIGNIFICANT
WIDESPREAD RAINFALL THURSDAY.
STAY TUNED.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...HWJIV
LONG TERM...BGM
AVIATION...BGM
FIRE WEATHER...HWJIV
HYDROLOGY...HWJIV
AREA FORECAST DISCUSSION
NWS NEW YORK NY
645 AM EDT MON JUN 30 2014
.SYNOPSIS...
THE REGION WILL BE IN BETWEEN THE BERMUDA HIGH AND A SLOWLY
APPROACHING COLD FRONT THROUGH WEDNESDAY NIGHT. THE FRONT WILL
MOVE SLOWLY ACROSS FROM THURSDAY INTO FRIDAY. POTENTIAL LOW
PRESSURE MOVING NORTH ALONG THE EAST COAST SHOULD PASS SOUTH OF
THE REGION FRIDAY INTO FRIDAY NIGHT. HIGH PRESSURE WILL THEN BUILD
IN FOR THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MID AND HIGH LEVEL CLOUDS CONTINUE TO SPREAD ACROSS WESTERN
SECTIONS OF THE CWA. MORNING STRATUS WILL BURN OFF QUICKLY
EASTERN LOCATIONS. SPOTTY SHOWERS APPROACH FROM THE WEST.
BROKEN CLOUDS...MENTIONED ABOVE...PASS ACROSS THE REGION THIS
MORNING AND THEN THIN THIS AFTERNOON.
HAVE CONTINUED THE 20 TSTM POP FOR ORANGE COUNTY FOR LATE AFTN AS
A DISSIPATING STORM COULD MAKE IT INTO THAT PART OF THE
FORECAST AREA.
HIGH TEMPS WILL BE NEAR 80 FOR THE COASTAL REGION IN A REPEAT OF
SUNDAY`S SEA BREEZE PATTERN. AWAY FROM THE COAST...MID 80S
EXPECTED...THOUGH THIS DEPENDS SOMEWHAT ON THE AMOUNT OF
CLOUD COVER.
THERE IS A MODERATE RISK OF RIP CURRENTS AT ATLANTIC BEACHES TODAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
DEW POINTS CONTINUE A SLOW INCREASE THROUGH THE PERIOD AS
SOUTHERLY FLOW GRADUALLY INCREASES.
HAVE REMOVED THE FOG FROM THE FORECAST FOR TONIGHT. THINKING IS
THAT WE MAY FORM MORE OF A LOW STRATUS CONDITION ALONG THE COAST.
THIS BASED ON LATEST RAP SOUNDINGS AND MOS GUIDANCE. WITH WATER
TEMPS AROUND 70...ADVECTION FOG DOES NOT SEEM LIKELY.
ON TUESDAY...TEMPS CONTINUE TO SLOWLY WARM AND HAVE GONE WITH THE
WARMER GFS MOS.
CONTINUED THE 20-30 POP TO THE NW OF NYC WITH SBCAPE IN THE NAM
NEARING 1000 J/KG.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
ACTIVE WEATHER POSSIBLE LATE IN THE WEEK.
EAST COAST RIDGE GIVES WAY TO APPROACHING TROUGH MID TO LATE WEEK.
SFC HIGH PRESSURE OVER THE ATLANTIC DEPARTS AS THE SLOW MOVING COLD
FRONT APPROACHES THE AREA.
WARM AND HUMID WEATHER IS EXPECTED...WITH MAINLY DIURNALLY DRIVEN
SHOWERS AND THUNDERSTORMS THROUGH WEDNESDAY...WITH HIGHEST POPS
ACROSS THE INTERIOR. THEN POPS INCREASE THURSDAY...THURSDAY NIGHT
AND FRIDAY AS THE FRONT NEARS. PLENTY OF MOISTURE WILL BE TAPPED AS
TROPICAL LOW OFF THE SOUTHEAST COAST LOOKS TO GET PICKED UP BY
SOUTHERLY STEERING WINDS AHEAD OF THE TROUGH.
ECMWF...GFS SEEM TO BE IN REASONABLE AGREEMENT ON THE TRACK OF THE
FRONT...AND TROPICAL LOW. HEAVY RAIN IS POSSIBLE LATER
THURSDAY...THURSDAY NIGHT AND POSSIBLY INTO FRIDAY.
THE TROUGH MOVES ACROSS THE NORTHEAST WITH A RIDGE BUILDING IN
BEHIND FOR A GOOD PORTION OF THE WEEKEND.
WARM TEMPS ARE EXPECTED AS PERSISTENT SOUTHERLY FLOW PREVAILS. ABOVE
NORMAL READINGS CAN BE EXPECTED TUESDAY NIGHT THROUGH WEDNESDAY
NIGHT...WITH CLOSER TO NORMAL READINGS THEREAFTER. HOTTEST DAY THIS
TIME FRAME APPEARS TO BE WEDNESDAY WITH READINGS IN THE 80S TO
AROUND 90.
INCREASING CLOUDS AND HIGHER COVERAGE OF SHOWERS/TSTMS THURSDAY AND
FRIDAY WILL KNOCK A FEW DEGREES OFF DAYTIME TEMPS. PLENTY OF
SUNSHINE OVER THE WEEKEND SHOULD RESULT IN NEAR NORMAL READINGS BEHIND
THE LOW/FRONT.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
HIGH PRESSURE OFF THE MID ATLANTIC COAST WILL DRIFT SLOWLY
EASTWARD...WITH CONTINUED S-SW FLOW.
VFR EXCEPT AT KGON...WHERE LOW STRATUS THAT DEVELOPED OVER
INTERIOR SE CT SHOULD SPREAD DOWN TOWARD THE COAST. CANNOT TOTALLY
RULE OUT EXPANSION TO KBDR OR KISP...AND WILL HAVE TO WATCH THIS
CAREFULLY INTO THE EARLY DAYLIGHT HOURS.
AFTERNOON SEA BREEZES WILL INCREASE WINDS TO 10 TO 15 KT AT THE
COASTAL TERMINALS. GUSTS UP TO 20 KT ARE POSSIBLE FROM LATE DAY
INTO EARLY EVENING AT KJFK/KLGA/KISP. WINDS DIMINISH THEREAFTER.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS
CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.
KLGA FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.
KEWR FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH
IMPLIES SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.
KHPN FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.
KISP FCSTER COMMENTS: BRIEF IFR CIGS POSSIBLE BEFORE 13Z.
.OUTLOOK FOR 06Z TUE THROUGH FRI...
.LATE MON NIGHT...PATCHY LOW CLOUDS WITH MVFR OR IFR CONDS ARE
LIKELY AT KGON...AND POSSIBLE AT THE OTHER TERMINALS LATE.
.TUE...CHANCE OF AN AFTERNOON TSTM WITH BRIEF MVFR OR LOWER CONDS
AND/OR AND GUSTY WINDS AT KSWF. FOG AND LOW STRATUS WITH MVFR OR
LOWER CONDS LIKELY LATE AT NIGHT.
.WED...FOG AND LOW STRATUS WITH MVFR OR LOWER CONDS BURNING OFF
EARLY IN THE MORNING. CHANCE OF SHOWERS/TSTMS WITH MVFR OR LOWER
CONDS IN THE AFTERNOON MAINLY FROM NYC METRO NORTH AND
WEST...SPREADING TO THE COAST IN THE EVENING.
.THU-FRI...NUMEROUS SHOWERS/TSTMS...WITH IFR CONDS IN HEAVY
RAIN POSSIBLE.
&&
.MARINE...
SEA BREEZES AGAIN LATE THIS AFTN WILL RESULT IN A PERIOD OF 15 KT
WITH GUST UP TO 20 KT ON THE WATERS. HIGHEST WOULD BE IN SOUTH OF
THE ROCKAWAYS.
SEA BREEZES ARE STRONGER YET TUESDAY AFTN WITH GUSTS UP TO 25 KT
AND THE POTENTIAL FOR SCA CONDITIONS...ESPECIALLY ON THE OCEAN.
PERSISTENT SOUTHERLY FLOW TUESDAY NIGHT WILL DIMINISH WEDNESDAY AND
THURSDAY AS A COLD FRONT APPROACHES AND THE PRESSURE GRADIENT
WEAKENS. WITH THE FRONT SLOWLY MOVING ACROSS THE WATERS EARLY
FRIDAY...WINDS REMAIN RATHER LIGHT. NEED TO MONITOR EVENTUAL
PROGRESSION OF A TROPICAL LOW LATE FRIDAY AS IT POSSIBLY APPROACHES
THE WATERS FROM THE SOUTH.
OCEAN SEAS OF 3 TO 6 FEET TUESDAY NIGHT WILL SUBSIDE AS THE
SOUTHERLY WINDS DIMINISH WEDNESDAY THROUGH THURSDAY. AT THIS
TIME...SEAS SHOULD REMAIN BELOW 5 FT MOST OF FRIDAY...BUT WOULD
LIKELY BUILD LATE IN THE DAY DEPENDING ON TRACK AND STRENGTH OF LOW
PRESSURE TO THE SOUTH.
&&
.HYDROLOGY...
NO SIGNIFICANT PRECIPITATION IS EXPECTED INTO TUESDAY.
THERE IS THE POTENTIAL FOR SIGNIFICANT RAINFALL TOWARD THE END OF
THE WEEK...THURSDAY AND THURSDAY NIGHT. AT THIS TIME THERE IS TOO
MUCH UNCERTAINTY TO SPECIFY EXACT AMOUNTS OR SPECIFIC THREATS.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TONGUE/PW
NEAR TERM...TONGUE/PW
SHORT TERM...TONGUE
LONG TERM...PW
AVIATION...GOODMAN
MARINE...TONGUE/PW
HYDROLOGY...TONGUE/PW
AREA FORECAST DISCUSSION
NWS ALBANY NY
634 AM EDT MON JUN 30 2014
.SYNOPSIS...
HIGH PRESSURE OFFSHORE WILL TRANSFORM INTO A BERMUDA HIGH. A WEAK
WARM FRONT CROSSING THE REGION TODAY WILL BRING SOME WIDELY
SCATTERED SHOWERS AND MAYBE A THUNDERSTORM. IT WILL THEN TURN MORE
HUMID AND HOT MID WEEK WITH SCATTERED MAINLY AFTERNOON
THUNDERSTORMS. WHILE MOST OF THE TIME WILL BE RAINFREE ANY
THUNDERSTORM THAT DEVELOPS COULD CONTAIN HEAVY RAINFALL AND GUSTY
WINDS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 630 AM EDT...SHOWERS STILL WORKING FROM WEST TO EAST ACROSS
THE MOHAWK VALLEY AND ABOUT TO MOVE INTO THE SCHOHARIE VALLEY. THEY
HAVE WEAKENED A LITTLE MORE BUT SOME SHOWERS STILL LOOK TO MAKE IT
INTO THE HUDSON VALLEY AND EVEN POINTS EASTWARD (ISOLATED).
TEMPERATURES WERE VERY MILD IN THE 60S...BUT DEWPOINTS WERE IN THE
50S SO NOT THAT MUGGY OUT.
FOR THIS UPDATE...ONLY VERY MINOR TWEAKING OF THE HOURLY GRIDS
(INCLUDING POP AND WEATHER).
THE LINE OF SHOWERS WAS THE RESULT OF A SECONDARY WARM
FRONT...REALLY MORE LIKE A DEWPOINT DISCONTINUITY LINE OVER CENTRAL
NEW YORK. DEWPOINTS ON THE EAST SIDE OF THIS BOUNDARY WERE STILL
GENERALLY IN THE 50S...AND IN SOME CASES...FALLING. TO THE WEST OF
THIS BOUNDARY...THEY HAD RISEN WELL INTO THE 60S.
THE 08Z HRRR STILL INDICATED SHOWER AND AFTERNOON THUNDERSTORM
ACTIVITY VERY RANDOMLY DISTRIBUTED OVER THE REGION...MAINLY WEST OF
THE HUDSON VALLEY...WHERE INSTABILITY LOOKS TO BE A LITTLE
BETTER...AS OPPOSED TO FURTHER EAST. UP TO 1000 J/KG OF INSTABILITY
IS POSSIBLE WEST OF THE HUDSON VALLEY. WE HAVE WE PLACED 40 POPS TO
THE NW OF THE CAPITAL REGION...30 CAPITAL REGION...ONLY 20 (LATE)
FURTHER SOUTH AND EAST.
DUE TO A LITTLE MORE IN THE WAY OF CLOUDS AND THE FRONT
NEARBY...TEMPERATURES TODAY COULD ACTUALLY BE A POINT OR TWO LOWER
THAN YESTERDAY BUT HUMIDITY WILL BEGIN TO CREEP UPWARD.
A SOUTH WIND WILL PREVAIL 5 TO 15 MPH TODAY. LOOK FOR HIGHS IN THE
MID 80S MOST VALLEY LOCATIONS...CLOSER TO 80 HIGHER TERRAIN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
ANY THUNDERSTORM ACTIVITY SHOULD DWINDLE THIS EVENING WE LOOSE THE
HEATING. ALSO...THE AFOREMENTIONED WARM FRONT WILL LIKELY HAVE MOVED
TO OUR EAST BY THEN.
WE WILL ULTIMATELY BE LEFT WITH A MUGGY SOMEWHAT HAZY NIGHT. A SOUTH
WIND WILL CONTINUE 5-10 MPH. OVERNIGHT LOWS WILL BE IN THE MID TO
UPPER 60S.
TUESDAY LOOKS TO BE A HOT ONE. BERMUDA HIGH OFFSHORE WILL PUMP A
SOUTHWEST FLOW OUR WAY. THIS FLOW WILL SEND H850 TEMPERATURES TO
NEAR 20C ACROSS MUCH OF OUR REGION. DEWPOINTS WILL CLIMB WELL INTO
THE 60S. WITH A GOOD DEAL OF HAZY SUNSHINE...THIS WILL TRANSLATE TO
SURFACE TEMPERATURES HITTING CLOSE TO 90 DEGREES IN VALLEY
LOCATIONS...LOWER TO MID 80S HIGHER TERRAIN.
THE DAY WILL START OUT MAINLY RAINFREE. HOWEVER...INSTABILITY LOOKS
TO RAMP UP TO WELL OVER 1500 J/KG DURING THE AFTERNOON. THIS COULD
BE ENOUGH INSTABILITY WHEN COMBINED WITH A VERY WEAK DISTURBANCE
SPARKED BY AN UPSTREAM TROUGH...TO PRODUCE WIDELY SCATTERED
THUNDERSTORMS DURING THE AFTERNOON. WHILE COVERAGE OF THE
THUNDERSTORMS LOOKS WIDELY SCATTERED...ANY THUNDERSTORM THAT DOES
FORM AS A SLIGHT CHANCE OF PRODUCING GUSTY WINDS AND HEAVY
RAINFALL...AND COULD PULSE BRIEFLY TO SEVERE LIMITS...MAINLY WIND
DAMAGE.
THUNDERSTORMS WILL DIMINISH AGAIN TUESDAY NIGHT AS ONCE AGAIN IT
WILL BE QUITE MUGGY. OVERNIGHT LOWS WILL LIKELY STAY AT OR ABOVE 70
IN THE HUDSON VALLEY FROM THE CAPITAL REGION SOUTHWARD...LOWER TO
MID 60S HIGHER TERRAIN.
WEDNESDAY WILL BE HOT AGAIN. THIS TIME HOWEVER...A COLD FRONT WILL
BE APPROACHING FROM THE NORTHWEST. EITHER THE FRONT...OR MORE LIKELY
A PRE-FRONTAL TROUGH LOOKS TO BE FOCUS FOR ANY CONVECTION THAT
DEVELOPS MAINLY DURING THE AFTERNOON. WE HAVE INCREASED POPS TO 50
DURING THE AFTERNOON.
DEPENDING ON HOW MUCH SUNSHINE WE RECEIVE TEMPERATURES COULD ONCE
AGAIN HIT 90 OR A LITTLE HIGHER ACROSS THE HUDSON VALLEY...MID OR
UPPER 80S ELSEWHERE ACROSS THE REGION. WE EXPECT MORE SUNSHINE THAN
CLOUDS...AT LEAST THROUGH THE TIME OF THE PEAK HEATING.
THE COLD FRONT (OR FRONTS) WILL SLOWLY MOVE THROUGH WEDNESDAY NIGHT
SO SHOWERS AND THUNDERSTORM ACTIVITY SHOULD CONTINUE. OVERNIGHT LOWS
WILL COOL TO THE 50S ACROSS THE ADIRONDACKS PARK WHERE THE FRONT IS
FORECAST TO MOVE THROUGH. FURTHER SOUTH...LOWS WILL GENERALLY
REMAIN IN THE 60S.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
MOST OF THE ATTENTION THIS UPCOMING LONG TERM PERIOD WILL BE WHAT IF
ANY IMPACTS WILL OCCUR ACROSS THE CWFA FROM THE DEVELOPING TROPICAL
ENTITY OFF THE SOUTHEAST COAST. LATEST GLOBAL MODELS CONTINUE TO
SUGGEST THIS TROPICAL ENTITY WILL TRACK OFF THE ATLANTIC COAST.
HOWEVER...THIS IN TURN MAY HAVE AN IMPACT WITH A SLOWER COLD FRONTAL
PASSAGE FORECAST ON THURSDAY. FURTHERMORE...WHILE STILL QUITE EARLY
IN THE FORECAST PROCESS...A POTENTIAL "PRE" EVENT MAY UNFOLD FOR
PORTIONS OF OUR REGION. GIVEN THE UNCERTAINTY...WE WILL HOLD ONTO
AND EXPAND A BIT THE POPS/WX GRIDS THROUGH MOST OF THURSDAY INTO
THURSDAY NIGHT. GUIDANCE NUMBERS DO LOOK A LITTLE HIGH GIVEN THE
EXPECT CLOUD COVER AND THE CHANCE FOR PRECIP AS WE WILL SHADE
SLIGHTLY COOLER PER THE WPC/ECMWF NUMBERS.
THEREAFTER...A BROAD ANTICYCLONIC FLOW /SURFACE HIGH/ SLOWLY BUILDS
ACROSS THE REGION INDEPENDENCE DAY AND INTO THE HOLIDAY WEEKEND.
THIS COULD BRING ABOUT THE FIFTH CONSECUTIVE DRY WEEKEND TO THE
REGION AS SUBSIDENCE INCREASES IN THE WAKE OF THE COASTAL EVENT AND
RISING HEIGHTS ALOFT. AS SUNSHINE INCREASES...SO TOO WILL BE THE
SURFACE TEMPERATURES WITH MAINLY LOWER HALF OF THE 80S FOR AFTERNOON
HIGHS AND OVERNIGHT LOWS INTO THE 50S AND LOWER 60S.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
MAINLY SKC/CLR ACROSS THE TAF LOCATIONS...HOWEVER...AS SEEN IN THE
SATELLITE IMAGERY THERE WILL BE AN INCREASE IN HIGH AND MID LEVEL
CLOUDS OVERNIGHT. THIS WILL ALSO RESULT IN A LOWER PROBABLY FOR
FOG FORMATION AS WE WILL PLACE A VCFG/MIFG IN THE TAFS /WITH THE
EXCEPTION OF KALB/. A LIGHT SOUTHERLY WIND THE REMAINDER OF THE
OVERNIGHT LESS THAN 5KTS. AS FOR SHOWER POTENTIAL...EXPECTATIONS
REMAIN ALONG A WEAKENING TREND AS THIS ACTIVITY TRACKS EASTS.
A MAINLY CLOUDY...VFR...START DAYLIGHT MONDAY MORNING AS WEAK FRONT
MOVES ACROSS THE REGION. THE CHANCE FOR SHOWERS REMAINS LOW AS WE
WILL CONTINUE WITH A VCSH AT THIS TIME. THOSE CLOUDS ARE EXPECTED
TO BREAK UP BY AFTERNOON. A LIGHTLY SOUTHERLY WIND AT 10KTS OR LESS
ARE EXPECTED.
INCREASING LOW LEVEL MOISTURE WILL ALLOW FOR BR/HZ TO DEVELOP MONDAY
EVENING AND MAY POSE A THREAT FOR MVFR/IFR CONDITIONS LATER MONDAY
NIGHT.
OUTLOOK...
MON NIGHT: LOW OPERATIONAL IMPACT. PATCHY FG.
TUE-WED NIGHT: MODERATE OPERATIONAL IMPACT.BREEZY CHANCE OF
SHRA...TSRA. THU: HIGH OPERATIONAL IMPACT. LIKELY SHRA...TSRA.
THU NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
INDEPENDENCE DAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
&&
.FIRE WEATHER...
MOST AREAS DID NOT SEE A FULL RECOVERY OVERNIGHT DUE TO A BREEZE AND
HIGH CLOUDS. HOWEVER...RH VALUES WILL REMAIN SLIGHTLY ELEVATED
THROUGHOUT THE DAY...BOTTOMING OUT AROUND 50 PERCENT. THERE WILL BE
MORE CLOUDS THAN YESTERDAY ALONG WITH WIDELY SCATTERED SHOWERS AND
MAYBE AN AFTERNOON THUNDERSTORM AROUND BUT MOST AREAS WILL LIKELY
NOT PICK UP A QUARTER OF AN INCH.
A NEARLY FULL RECOVERY LIKELY TONIGHT AS IT WILL BE MORE HUMID AND
THE BREEZE ONLY SLIGHT.
HOT TUESDAY WITH MOST VALLEY AREAS APPROACHING OR EVEN ECLIPSING 90
DEGREES. AFTERNOON RH VALUES WILL AROUND 50 PERCENT ONCE MORE.
A SOUTH TO SOUTHWEST WIND WILL INCREASE TO 10-15 MPH...WITH SOME
AFTERNOON GUSTS TO 25 MPH ON TUESDAY.
AFTERNOON THUNDERSTORMS ARE POSSIBLE ONCE MORE ON...MAINLY WEST OF
THE HUDSON VALLEY ON TUESDAY.
MORE THUNDERSTORMS POSSIBLE ALONG WITH HOT AND HUMID WEATHER FOR
WEDNESDAY. HOWEVER...A COLD FRONT WILL LIKELY WORK THROUGH WEDNESDAY
NIGHT...STALLING JUST SOUTH OF OUR REGION ON THURSDAY.
&&
.HYDROLOGY...
NO HYDRO PROBLEMS EXPECTED TODAY.
THERE WILL LIGHT SHOWERS AROUND THIS MORNING AND THE POSSIBILITY OF
WIDELY SCATTERED AFTERNOON THUNDERSTORMS. THESE DO NOT LOOK TO
PRODUCE AVERAGE BASIN RAINFALLS OF A QUARTER OF AN INCH OR MORE.
MORE ROBUST THUNDERSTORMS ARE POSSIBLE TUESDAY...MAINLY WEST OF THE
HUDSON VALLEY. SOME OF THESE COULD PRODUCE LOCALIZED DOWNPOURS AS
PWATS LOOK TO RAMP TO NEARLY 2 INCHES. ANY OF THESE THUNDERSTORMS
COULD PRODUCE PONDING OF WATER ON ROADWAYS AND AREAS OF POOR
DRAINAGE.
EVEN SO...AVERAGE BASIN RAINFALL ON TUESDAY WILL LIKELY REMAIN AT OR
BELOW A QUARTER INCH. MAJOR RIVERS WILL LIKELY SEE ONLY MINOR RISES
IF THAT.
BY WEDNESDAY...AS COLD FRONT PLOWS INTO THE TROPICAL
AIR...THUNDERSTORMS COULD BE A BIT MORE NUMEROUS AND AGAIN CONTAIN
TORRENTIAL DOWNPOURS LEADING TO MINOR FLOODING.
BY THURSDAY...THIS FRONT LOOKS TO STALL JUST SOUTH OF OUR REGION. AT
THE SAME TIME...SOME SORT OF TROPICAL SYSTEM LOOKS TO SPIN UP ALONG
THE EASTERN SEABOARD TO OUR SOUTH. WHILE ALL MODELS HAVE THE ACTUAL
ENTITY MISSING OUR REGION...A PREDECESSOR RAINFALL EVENT (PRE) IS
FORECAST BY ALL MODELS TO FORM ALONG THIS BOUNDARY. THIS QUESTION IS
HOW FAR NORTH THIS PRE WILL GET WHICH COULD PRODUCE SIGNIFICANT
WIDESPREAD RAINFALL THURSDAY.
STAY TUNED.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...HWJIV
LONG TERM...BGM
AVIATION...BGM
FIRE WEATHER...HWJIV
HYDROLOGY...HWJIV
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
1112 AM EDT MON JUN 30 2014
.UPDATE...
RAIN CONTINUES ACROSS THE NORTHERN PORTION OF THE STATE WITH
LIMITED LIGHTNING ACTIVITY. HRRR HAS BEEN HANDLING THIS ACTIVITY
THE BEST IN TERMS OF LOCATION AND THUS NEAR TERM FORECAST UPDATES
WERE TO TREND THE POPS TOWARDS THE HRRR. HAVE INCREASED
SIGNIFICANTLY THE POPS ACROSS NORTH GEORGIA THROUGHOUT THE MORNING
AND INTO THE AFTERNOON. ALSO HAVE INCREASED POPS 10-20 PERCENT
ACROSS MANY AREAS IN CENTRAL GA.
HEAVY RAIN REMAINS THE MAIN CONCERN ESPECIALLY ACROSS NORTH
GEORGIA WITH MULTIPLE ROUNDS OF RAIN OVER A FEW DAYS AND LONG
PERIODS OF RAIN THIS MORNING. STILL AGREE WITH THE POTENTIAL OF
STRONG TO A FEW SEVERE STORMS TODAY.
&&
.PREV DISCUSSION...
SHORT TERM /TODAY THROUGH TUESDAY/...
/ISSUED 339 PM EDT MON JUN 30 2014/
LINE OF WEAKENING CONVECTION ASSOCIATED WITH A MODERATE SHORT
WAVE RIDING OVER THE TOP OF THE WEAK UPPER RIDGE IS EXPECTED TO
CONTINUE WEAKENING AS IT SWEEPS ACROSS NORTH GEORGIA THROUGH THE
EARLY MORNING HOURS. THE SYNOPTIC SETUP TODAY REMAINS VERY SIMILAR
TO YESTERDAY WITH GEORGIA ON THE PERIPHERY OF THE WEAK UPPER RIDGE
AND A MODERATE SHORT WAVE RIDING OVER THE TOP ACROSS NORTH AND
EAST GEORGIA. I HAVE CONCENTRATED MY BETTER POPS ACROSS THAT AREA
THIS AFTERNOON BUT HAVE KEPT THE PERCENTAGES LIMITED TO THE MID TO
HIGH CHANCE RANGE FOR NOW. HAD A FEW STORMS REACH THE STRONG TO
MARGINALLY SEVERE LEVEL YESTERDAY AND CANNOT RULE OUT THE SAME
THIS AFTERNOON INTO THE EARLY EVENING...HOWEVER I DO NOT EXPECT
WIDESPREAD SEVERE THUNDERSTORMS. AMPLE PRECIP WATER WILL MAKE
HEAVY RAIN/MINOR FLOODING A POSSIBILITY AGAIN AS WELL. MODELS
CONTINUE TO SHOW THE SLOW...GRADUAL WEAKENING OF THE UPPER RIDGE
INTO TUESDAY... HOWEVER ALL ARE SHOWING A LACK OF THE MID/UPPER-
LEVEL SHORT WAVE FORCING THAT WE SAW YESTERDAY AND ANTICIPATE
TODAY...SO I HAVE GONE WITH A GENERAL LESSENING IN CONVECTIVE
COVERAGE.
OVERNIGHT LOW TEMPERATURES ARE EXPECTED TO REMAIN NEAR SEASONAL
NORMALS...WITH AFTERNOON HIGHS REACHING A FEW DEGREES ABOVE IN MOST
AREAS OUTSIDE OF ANYONE WHO GETS SOME EARLY PRECIPITATION. HEAT
INDEX VALUES ARE FORECAST TO REMAIN BELOW ADVISORY LEVELS...BUT ARE
LIKELY TO APPROACH 100-102 ACROSS OUR CENTRAL GEORGIA COUNTIES TODAY
AND TUESDAY. AMOUNT OF CLOUD COVER AND CONVECTIVE COVERAGE WILL HAVE
A NOTICEABLE IMPACT ON WHICH AREAS PUSH THE 100 DEGREE HEAT INDEX
LINE EACH AFTERNOON AND BOTH ARE EXPECTED TO BE SOMEWHAT VARIABLE
TODAY BUT LESS ON TUESDAY.
20
LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
/ISSUED 339 PM EDT MON JUN 30 2014/
LONG RANGE MODELS CONTINUE TO SHOW HIGH PRESSURE WEAKENING ITS
GRIP TUESDAY NIGHT AND WEDNESDAY AS A LONG WAVE TROUGH DEEPENS
ACROSS THE MS VALLEY REGION. THIS SYSTEM PUSHES A COLD FRONT INTO
THE OHIO AND UPPER TN VALLEY REGIONS BY WEDNESDAY NIGHT. AT THIS
SAME TIME... THE GFS AND ECMWF ARE SHOWING A LOW PRESSURE SYSTEM
ALONG THE EAST CENTRAL FLORIDA COAST TUESDAY NIGHT... AND DRIFTING
IT NORTHWARD TO JUST OFF THE GEORGIA COAST ON WEDNESDAY AND
WEDNESDAY NIGHT. MODELS SHOW FAIRLY GOOD AGREEMENT WITH THE LONG
WAVE TROUGH PUSHING EASTWARD AND PUSHING A COLD FRONT INTO THE
LOWER TN VALLEY ON THURSDAY... WHILE IT ALSO SERVES TO LIFT THE
LOW PRESSURE SYSTEM NORTHEASTWARD AND ALONG THE SOUTH AND NORTH
CAROLINA COASTS ON THURSDAY AND THURSDAY NIGHT. BY FRIDAY... BOTH
MODELS SHOW THE FRONT PUSHING INTO SOUTH GA WITH DRY HIGH PRESSURE
BUILDING IN OVER THE FORECAST AREA BY FRIDAY AFTERNOON. AT THIS
SAME TIME... THE SURFACE LOW OFF THE CAROLINAS LIFTS NORTHEASTWARD
AND TRACKS ALONG THE EAST CENTRAL AND NORTHEAST ATLANTIC COASTAL
AREAS THROUGH SATURDAY...THEN DRIFTING FURTHER OUT TO SEA SATURDAY
NIGHT AND SUNDAY. THIS LOW PRESSURE SYSTEM WILL HAVE TO BE
MONITORED CLOSELY FOR POTENTIAL TROPICAL DEVELOPMENT WITHIN THE
NEXT 3 TO 5 DAYS.
THE APPROACHING COLD FRONT AND POSITION OF THE SURFACE LOW OFF
THE GA COASTS ON WEDNESDAY...THEN ALONG THE CAROLINAS ON THURSDAY
WILL WARRANT A CHANCE POPS FOR MOST AREAS ON WEDNESDAY AND THURSDAY.
THEN AS THE COLD FRONT PUSHES SOUTH ON FRIDAY... EXPECT ADDED HIGH
PRESSURE SUBSIDENCE AND DRY AIR TO HOLD POPS DOWN TO ISOLATED
NORTH AND MAYBE LOW SCATTERED CENTRAL FOR FRIDAY AND SATURDAY...
AND POSSIBLY INTO SUNDAY. AS A RESULT... EXPECTING A NICE QUIET
WEATHER PATTERN FOR THE 4TH OF JULY WEEKEND.
AS FOR TEMPS... HAVE LEANED CLOSE TO A MEX/HPC BLEND FOR THROUGH
THE EXTENDED PERIOD...WITH COOLER HIGHS EXPECTED TO FILTER IN OVER
THE AREA FOR FRIDAY AND SATURDAY BEHIND THE FRONT. 39
AVIATION...
12Z UPDATE...
/ISSUED 725 AM EDT MON JUN 30 2014/
ONGOING CONVECTION MOVING ACROSS THE NORTHERN PORTION OF THE
FORECAST AREA IS EXPECTED TO REMAIN GENERALLY NORTH OF THE TAF SITES
THROUGH 18Z...ALTHOUGH AN ISOLATED SHOWER IS NOT IMPOSSIBLE AT ANY
OF THE TAF SITES. OTHERWISE CONVECTIVE ACTIVITY IS EXPECTED TO
BECOME MORE ACTIVE NEAR THE ATLANTA METRO AND ATHENS TAF SITES AFTER
18Z THROUGH 02Z. OTHERWISE...VFR CONDITIONS ARE EXPECTED TO
PREDOMINATE ACROSS THE FORECAST AREA THROUGH THE MAJORITY OF THE
FORECAST PERIOD OUTSIDE OF CONVECTION. SCATTERED MVFR OR LOWER
VISIBILITIES WILL CONTINUE BETWEEN 12Z AND 14Z IN FOG...MAINLY IN
AREAS THAT SAW HEAVIER RAIN IN THE PAST 24 HOURS. WINDS ARE LIGHT
AND VARIABLE...LESS THAN 5KTS...CURRENTLY BUT WILL BECOME WESTERLY
AND INCREASE TO 5-10KTS BY 15Z AND AFTER.
//ATL CONFIDENCE...06Z UPDATE...
MEDIUM TO HIGH.
20
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 91 70 93 73 / 80 40 20 20
ATLANTA 89 72 92 76 / 50 30 20 20
BLAIRSVILLE 84 65 88 69 / 100 40 30 20
CARTERSVILLE 89 68 92 71 / 60 30 20 20
COLUMBUS 93 74 94 76 / 50 20 20 10
GAINESVILLE 88 70 91 74 / 90 40 20 20
MACON 93 70 94 73 / 50 40 20 20
ROME 90 69 92 72 / 70 20 20 10
PEACHTREE CITY 90 67 92 70 / 50 20 20 10
VIDALIA 93 73 94 74 / 50 50 30 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...11
LONG TERM....DEESE
AVIATION...11
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1025 AM EDT MON JUN 30 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 325 AM EDT MON JUN 30 2014
THE APPROACH AND PASSAGE OF A STRONG COLD FRONT WILL BRING THE
CHANCE FOR THUNDERSTORMS THROUGH WEDNESDAY. THE GREATEST THREAT FOR
SEVERE WEATHER WILL EXIST TONIGHT INTO EARLY TUESDAY AS AN
INTENSIFYING LOW PRESSURE PASSES TO THE NORTH OF THE REGION.
CANADIAN HIGH PRESSURE WILL BUILD SOUTH INTO THE OHIO VALLEY BY
WEDNESDAY NIGHT...FINALLY PROVIDING A BREAK FROM THE RECENT STORMY
PATTERN. DRY PLEASANT WEATHER IS EXPECTED FOR MUCH OF THE HOLIDAY
WEEKEND.
&&
.NEAR TERM /TODAY/...
ISSUED AT 1015 AM EDT MON JUN 30 2014
UPDATE MAINLY FOCUSES ON RADAR TRENDS. WILL CONFINE CHANCE AND
HIGHER POPS TO THE WESTERN HALF OF THE FORECAST AREA AS COMPLEX/S
NET MOTION IS JUST EAST OF SOUTH ALONG THE PRESENT INSTABILITY
GRADIENT. PREVIOUS DISCUSSION FOLLOWS.
ISSUED AT 325 AM EDT MON JUN 30 2014
WEAK RIDGING ALOFT HAS BUILT INTO CENTRAL INDIANA EARLY THIS MORNING
RESULTING IN MAINLY CLEAR SKIES FOR THE MOMENT AND QUIET WEATHER SO
FAR. MUGGY AIRMASS ACROSS THE REGION WITH TEMPS MAINLY IN THE LOWER
70S AS OF 07Z.
INTERESTING 18 TO 24 HOURS UPCOMING FOR THE MIDWEST WITH AN
ANOMALOUSLY STRONG UPPER LOW DRIFTING INTO WESTERN ONTARIO AND
SEVERAL WAVES ALOFT ROTATING AROUND THE BASE OF THE TROUGH IN A FAST
ZONAL FLOW FROM THE CENTRAL PLAINS E/NE INTO THE GREAT LAKES.
ONGOING CONVECTIVE CLUSTER OVER NORTHERN ILLINOIS/EASTERN IOWA THIS
MORNING AND EXPECTED DEVELOPMENT LATER TODAY AS A STRONG SURFACE
WAVE EJECTS OUT OF THE CENTRAL PLAINS.
INITIAL ISSUE IS AFOREMENTIONED STORM CLUSTER MOVING THROUGH
NORTHERN ILLINOIS. STORMS ARE BEING FED BY A 40KT LOW LEVEL JET
TRANSPORTING RICH TROPICAL MOISTURE INTO THE MID MISSISSIPPI VALLEY.
MESOANALYSIS ALSO INDICATING THE ACTIVITY PROPAGATING ALONG AN
INSTABILITY AXIS AND THETA-E RIDGE. BULK OF THE SHORT RANGE MODEL
GUIDANCE GRADUALLY WEAKENS THE COMPLEX OVER THE NEXT 4-6 HOURS AS IT
TRACKS E/SE AWAY FROM THE DEEPER INSTABILITY AND MOISTURE. ALREADY
SEEING WARMING CLOUD TOPS ON THE SOUTHERN EDGE OF THE COMPLEX AS
STORMS INTERACT WITH WARMER MID LEVEL TEMPS WITH THE PREDOMINANT
FOCUS SHIFTING TO THE CONVECTION WEST OF CHICAGO IN THE VICINITY OF
THE BEST FORCING ALOFT AND INSTABILITY. WHILE STORMS WILL WEAKEN AS
THEY MOVE EAST...NOT COMPLETELY OUT OF THE QUESTION THAT PRECIP MAY
MAKE IT TO THE NORTHERN WABASH VALLEY BEFORE DIMINISHING AROUND OR
SHORTLY AFTER SUNRISE. OF GREATER IMPACT TO THE FORECAST AREA WILL
BE LEFTOVER CLOUD DEBRIS FROM THE COMPLEX WHICH IS LIKELY TO LIMIT
SURFACE HEATING THIS MORNING. WITH RISING 500MB HEIGHTS AS THE RIDGE
TO THE SOUTH FLEXES ITS MUSCLES HOWEVER...ANTICIPATE MOST OF THE
DEBRIS WILL BE GONE BY MIDDAY.
AFTERNOON SHOULD BE LARGELY QUIET FOR CENTRAL INDIANA AS THE WARMING
TEMPS ALOFT PROMOTE A CAP AROUND 700MB. WILL LEAVE A 20 POP IN FOR
ANY ISOLATED CONVECTION AS A WEAK WAVE ALOFT DRIFTS THROUGH THE
REGION DURING THE EARLY AFTERNOON...BUT THE CAP SHOULD KEEP A LID ON
MOST STORMS. FOCUS WILL SHIFT BACK TO NEBRASKA AND IOWA BY MID
AFTERNOON AS THE ARRIVAL OF A STRENGTHENING SURFACE LOW INTO AN
INCREASINGLY UNSTABLE ENVIRONMENT WILL SET THE STAGE FOR WIDESPREAD
ROBUST CONVECTIVE DEVELOPMENT FOR THE SECOND HALF OF THE
AFTERNOON...WITH STORMS RAPIDLY EXPANDING EAST INTO NORTHERN
ILLINOIS AND WISCONSIN BY EARLY EVENING. MORE ON POTENTIAL IMPACTS
TO OUR FORECAST AREA IN THE SHORT TERM SECTION.
TEMPS...DESPITE 850MB TEMPS RISING TO AROUND 20C BY LATE
AFTERNOON...CLOUD DEBRIS THIS MORNING AND CU DURING THE AFTERNOON
WILL LIMIT HEATING SLIGHTLY. LEANED TOWARDS WARMER METMOS WITH MUCH
OF THE FORECAST AREA WARMING TO 86-89.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
ISSUED AT 325 AM EDT MON JUN 30 2014
FORECAST CHALLENGES FOCUS PRIMARILY ON PRECIP CHANCES TONIGHT...AS
WELL AS TEMPS AND PRECIP CHANCES THROUGHOUT THE REMAINDER OF THE
SHORT TERM.
WELL DEVELOPED AND INTENSIFYING MESOSCALE CONVECTIVE COMPLEX TO THE
NORTHWEST OF THE REGION WILL BE ONGOING THIS EVENING. SURFACE LOW
WILL CONTINUE TO STRENGTHEN AS IT MOVES INTO THE WESTERN GREAT LAKES
BY LATE EVENING. WHILE CONVECTIVE FEEDBACK MAY BE CONTRIBUTING TO AN
OVERESTIMATION IN THE LOW LEVEL WIND FIELDS...OVERALL DYNAMICS ARE
EXTREMELY IMPRESSIVE FOR AN EARLY SUMMER SYSTEM. SUB 1000MB WAVES
WILL GET YOUR ATTENTION THIS TIME OF YEAR...LET ALONE THE
POSSIBILITY OF A SURFACE LOW INTENSITY IN THE VICINITY OF 990-995MB
BY THE EARLY OVERNIGHT OVER THE GREAT LAKES AS BEING ADVERTISED.
CONSIDERING THE AVAILABLE HIGH INSTABILITY TO GO ALONG WITH THE
PROGGED WIND FIELDS...FURTHER GROWTH IN AREAL COVERAGE AND INTENSITY
TO CONVECTION IS ANTICIPATED THROUGH THE EVENING.
WHILE MUCH GREATER CERTAINTY EXISTS WITH RESPECT TO POTENTIAL FOR
SEVERE CONVECTION OVER THE WESTERN GREAT LAKES...THE PICTURE IS NOT
AS CLEAR FOR CENTRAL INDIANA. INITIALLY...MODEL SOUNDINGS INDICATE
THE CAP STILL PRESENT THROUGH THE EVENING WITH COOLING ALOFT TOWARDS
06Z AS MID LEVEL HEIGHTS TUMBLE. CORE OF THE HIGHER WIND FIELDS AND
FORCING ALOFT WILL PASS TO THE NORTH OF THE FORECAST AREA
OVERNIGHT...BUT THE LOW LEVEL JET WILL PROVIDE A GLANCING BLOW WITH
850MB WINDS PEAKING AT 35-40KTS OVER NORTHERN COUNTIES AROUND 06Z.
WHILE THE ENVIRONMENT WILL NOT BE AS CONDUCIVE TO MAINTAINING THE
DEGREE OF CONVECTIVE INTENSITY...FEEL THE STRONGER LOW LEVEL WIND
FIELDS ALONG WITH PLENTY OF INSTABILITY PRESENT SHOULD BE MORE THAN
SUFFICIENT FOR STORMS TO MAKE IT INTO THE FORECAST AREA AROUND OR
SHORTLY AFTER MIDNIGHT. HI-RES NMM/ARW SUPPORT THIS THINKING...BOTH
INDICATING A WEAKENING SQUALL LINE IMPACTING NORTHWEST HALF OF THE
FORECAST AREA BETWEEN 06-09Z. MAIN IMPACTS FROM THE LINE BESIDES
TORRENTIAL RAINS WOULD BE DAMAGING WINDS AS A WELL DEVELOPED COLD
POOL LIKELY TO ACCOMPANY THE STORMS. HAVE FOCUSED HIGHEST POPS
MAINLY ALONG AND NORTH OF I-70 WITH LOWER POPS FURTHER SOUTH. VERY
POSSIBLE THAT SOUTHERN PORTIONS OF THE FORECAST AREA SEE NO RAIN AT
ALL.
LOW PRESSURE WILL LIFT OUT INTO QUEBEC ON TUESDAY LEAVING THE
REMNANT FRONTAL BOUNDARY OVER THE REGION. PRESENCE OF THE FRONT
ALONG WITH ANY LEFTOVER OUTFLOW BOUNDARIES FROM CONVECTION TONIGHT
MAY SERVE TO INITIATE NEW STORMS AS HEATING PEAKS TUESDAY
AFTERNOON...ESPECIALLY ACROSS THE SOUTHERN HALF OF THE FORECAST
AREA. HOWEVER IN THE ABSENCE OF MORE SUBSTANTIAL FORCING
ALOFT...HAVE LOW CONFIDENCE IN HOW EXTENSIVE THE COVERAGE WILL BE.
WILL CARRY ONLY ISOLATED POPS AT THIS TIME WITH MAINLY DRY WEATHER
TUESDAY NIGHT AS THE FRONT SHIFTS SOUTH OF THE OHIO RIVER.
UPPER TROUGH WILL REMAIN ACROSS THE GREAT LAKES INTO WEDNESDAY WITH
ANOTHER WAVE ALOFT ROTATING THROUGH THE REGION ALONG WITH A
SECONDARY FRONT. WHILE BETTER INSTABILITY WILL BE DISPLACED TO THE
SOUTH OF THE FORECAST AREA CLOSER TO THE MAIN FRONT...EXPECT
SCATTERED CONVECTIVE DEVELOPMENT FOCUSED ON WEDNESDAY AFTERNOON AND
EVENING. HIGH PRESSURE WILL BUILD IN WEDNESDAY NIGHT WITH COOLER AND
MUCH DRIER WEATHER...FINALLY GIVING CENTRAL INDIANA A BREAK FROM THE
UNSETTLED...STORMY AND HUMID WEATHER EXPERIENCED OVER THE LAST FEW
WEEKS.
TEMPS...LOW LEVEL THERMAL PROFILES ARE GENERALLY SIMILAR TO TODAY ON
TUESDAY...ESPECIALLY SOUTH OF I-70. ONCE AGAIN TRENDED TOWARDS
WARMER METMOS GUIDANCE WITH HIGHS IN THE MID/UPPER 80S. WENT A FEW
DEGREES ABOVE MAVMOS FOR WEDNESDAY AS THE 00Z GFS LOOKS OVERLY
AGGRESSIVE WITH BRINGING THE COOLER AIR INTO THE REGION...ESPECIALLY
WITH THE SECONDARY BOUNDARY AND UPPER WAVE IN THE AREA. PREFERRED
WARMER METMOS FOR OVERNIGHT LOWS THROUGH THE PERIOD. LOWS BY
WEDNESDAY NIGHT IN THE UPPER 50S/LOWER 60S WILL FEEL WONDERFUL.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
ISSUED AT 325 AM EDT MON JUN 30 2014
SURFACE HIGH PRESSURE MOVES THROUGH CENTRAL INDIANA DURING THE LONG
TERM. THIS WILL BRING DRY WEATHER WITH IT THROUGH MUCH OF THE PERIOD
ALONG WITH BELOW NORMAL TEMPERATURES FOR THE END OF THE WEEK.
NORTHERLY COMPONENT FLOW WILL USHER IN COOLER TEMPERATURES AND DRIER
DEW POINTS FOR THURSDAY AND FRIDAY WITH SATURDAY AND SUNDAY CLIMBING
BACK INTO THE LOW 80S AS THE HIGH PRESSURE CENTER MOVES TO THE EAST
AND SOUTHWESTERLY FLOW COMMENCES ON THE BACK SIDE. SUNDAY GFS AND
ECMWF ARE BOTH SHOWING A SHORTWAVE APPROACHING SO COULD SEE PRECIP
CHANCES ARRIVING AFTER THAT. PRIOR TO SUNDAY THOUGH MODELS ARE IN
GOOD AGREEMENT ON A DRY FORECAST.
&&
.AVIATION /DISCUSSION FOR 301500Z TAF UPDATE/...
ISSUED AT 1025 AM EDT MON JUN 30 2014
AREA OF THUNDERSTORMS SHOULD BE WEAKENING AS IT MOVES EAST TOWARD
KIND THIS MORNING...BUT LATEST TRENDS INDICATE THAT SOME THUNDER
SHOULD MAKE IT TO THE SITE AFTER 15Z /CLOSER TO 16Z/. HAVE INCLUDED
IFR VISIBILITY AND CEILING IN THE TEMPO. AFTER THE RAIN ENDS EXPECT
CONDITIONS TO SLOWLY IMPROVE TO VFR.
PREVIOUS DISCUSSION FOLLOWS...
SITES ARE STARTING OUT WITH MVFR CEILINGS AND EXPECT THIS TO
CONTINUE FOR A FEW HOURS BEFORE THEY SHOULD LIFT TO VFR. A
THUNDERSTORM COMPLEX CURRENTLY ACROSS NORTH CENTRAL ILLINOIS LOOKS
LIKE IT WILL HOLD TOGETHER TO IMPACT KLAF BEFORE FIZZLING OUT TO
SHOWERS. HRRR AND RAP DO NOT SHOW IT HOLDING TOGETHER EVEN THAT LONG
BUT RECENT RADAR TRENDS POINT OTHERWISE. THUS WILL TEMPO IN SOME
THUNDER AT KLAF TIMED TO MATCH CURRENT OBSERVATIONAL TRENDS. AT KHUF
WILL PUT IN SOME VCSH AS THERE IS NO LIGHTNING WITH THE ECHOES
HEADING THAT WAY. DOES NOT CURRENTLY LOOK LIKE THIS WILL IMPACT KIND
AND KBMG. ANOTHER ROUND OF STORMS SHOULD MOVE IN FROM THE NORTHWEST
TONIGHT BUT TIMING IS STILL A BIT IN THE AIR. WILL PUT IN A VCTS
DURING MOST LIKELY TIMEFRAME TO INDICATE CONVECTIVE POTENTIAL.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM...CP
AVIATION...CP/50
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1015 AM EDT MON JUN 30 2014
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 325 AM EDT MON JUN 30 2014
THE APPROACH AND PASSAGE OF A STRONG COLD FRONT WILL BRING THE
CHANCE FOR THUNDERSTORMS THROUGH WEDNESDAY. THE GREATEST THREAT FOR
SEVERE WEATHER WILL EXIST TONIGHT INTO EARLY TUESDAY AS AN
INTENSIFYING LOW PRESSURE PASSES TO THE NORTH OF THE REGION.
CANADIAN HIGH PRESSURE WILL BUILD SOUTH INTO THE OHIO VALLEY BY
WEDNESDAY NIGHT...FINALLY PROVIDING A BREAK FROM THE RECENT STORMY
PATTERN. DRY PLEASANT WEATHER IS EXPECTED FOR MUCH OF THE HOLIDAY
WEEKEND.
&&
.NEAR TERM /TODAY/...
ISSUED AT 1015 AM EDT MON JUN 30 2014
UPDATE MAINLY FOCUSES ON RADAR TRENDS. WILL CONFINE CHANCE AND
HIGHER POPS TO THE WESTERN HALF OF THE FORECAST AREA AS COMPLEX/S
NET MOTION IS JUST EAST OF SOUTH ALONG THE PRESENT INSTABILITY
GRADIENT. PREVIOUS DISCUSSION FOLLOWS.
ISSUED AT 325 AM EDT MON JUN 30 2014
WEAK RIDGING ALOFT HAS BUILT INTO CENTRAL INDIANA EARLY THIS MORNING
RESULTING IN MAINLY CLEAR SKIES FOR THE MOMENT AND QUIET WEATHER SO
FAR. MUGGY AIRMASS ACROSS THE REGION WITH TEMPS MAINLY IN THE LOWER
70S AS OF 07Z.
INTERESTING 18 TO 24 HOURS UPCOMING FOR THE MIDWEST WITH AN
ANOMALOUSLY STRONG UPPER LOW DRIFTING INTO WESTERN ONTARIO AND
SEVERAL WAVES ALOFT ROTATING AROUND THE BASE OF THE TROUGH IN A FAST
ZONAL FLOW FROM THE CENTRAL PLAINS E/NE INTO THE GREAT LAKES.
ONGOING CONVECTIVE CLUSTER OVER NORTHERN ILLINOIS/EASTERN IOWA THIS
MORNING AND EXPECTED DEVELOPMENT LATER TODAY AS A STRONG SURFACE
WAVE EJECTS OUT OF THE CENTRAL PLAINS.
INITIAL ISSUE IS AFOREMENTIONED STORM CLUSTER MOVING THROUGH
NORTHERN ILLINOIS. STORMS ARE BEING FED BY A 40KT LOW LEVEL JET
TRANSPORTING RICH TROPICAL MOISTURE INTO THE MID MISSISSIPPI VALLEY.
MESOANALYSIS ALSO INDICATING THE ACTIVITY PROPAGATING ALONG AN
INSTABILITY AXIS AND THETA-E RIDGE. BULK OF THE SHORT RANGE MODEL
GUIDANCE GRADUALLY WEAKENS THE COMPLEX OVER THE NEXT 4-6 HOURS AS IT
TRACKS E/SE AWAY FROM THE DEEPER INSTABILITY AND MOISTURE. ALREADY
SEEING WARMING CLOUD TOPS ON THE SOUTHERN EDGE OF THE COMPLEX AS
STORMS INTERACT WITH WARMER MID LEVEL TEMPS WITH THE PREDOMINANT
FOCUS SHIFTING TO THE CONVECTION WEST OF CHICAGO IN THE VICINITY OF
THE BEST FORCING ALOFT AND INSTABILITY. WHILE STORMS WILL WEAKEN AS
THEY MOVE EAST...NOT COMPLETELY OUT OF THE QUESTION THAT PRECIP MAY
MAKE IT TO THE NORTHERN WABASH VALLEY BEFORE DIMINISHING AROUND OR
SHORTLY AFTER SUNRISE. OF GREATER IMPACT TO THE FORECAST AREA WILL
BE LEFTOVER CLOUD DEBRIS FROM THE COMPLEX WHICH IS LIKELY TO LIMIT
SURFACE HEATING THIS MORNING. WITH RISING 500MB HEIGHTS AS THE RIDGE
TO THE SOUTH FLEXES ITS MUSCLES HOWEVER...ANTICIPATE MOST OF THE
DEBRIS WILL BE GONE BY MIDDAY.
AFTERNOON SHOULD BE LARGELY QUIET FOR CENTRAL INDIANA AS THE WARMING
TEMPS ALOFT PROMOTE A CAP AROUND 700MB. WILL LEAVE A 20 POP IN FOR
ANY ISOLATED CONVECTION AS A WEAK WAVE ALOFT DRIFTS THROUGH THE
REGION DURING THE EARLY AFTERNOON...BUT THE CAP SHOULD KEEP A LID ON
MOST STORMS. FOCUS WILL SHIFT BACK TO NEBRASKA AND IOWA BY MID
AFTERNOON AS THE ARRIVAL OF A STRENGTHENING SURFACE LOW INTO AN
INCREASINGLY UNSTABLE ENVIRONMENT WILL SET THE STAGE FOR WIDESPREAD
ROBUST CONVECTIVE DEVELOPMENT FOR THE SECOND HALF OF THE
AFTERNOON...WITH STORMS RAPIDLY EXPANDING EAST INTO NORTHERN
ILLINOIS AND WISCONSIN BY EARLY EVENING. MORE ON POTENTIAL IMPACTS
TO OUR FORECAST AREA IN THE SHORT TERM SECTION.
TEMPS...DESPITE 850MB TEMPS RISING TO AROUND 20C BY LATE
AFTERNOON...CLOUD DEBRIS THIS MORNING AND CU DURING THE AFTERNOON
WILL LIMIT HEATING SLIGHTLY. LEANED TOWARDS WARMER METMOS WITH MUCH
OF THE FORECAST AREA WARMING TO 86-89.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
ISSUED AT 325 AM EDT MON JUN 30 2014
FORECAST CHALLENGES FOCUS PRIMARILY ON PRECIP CHANCES TONIGHT...AS
WELL AS TEMPS AND PRECIP CHANCES THROUGHOUT THE REMAINDER OF THE
SHORT TERM.
WELL DEVELOPED AND INTENSIFYING MESOSCALE CONVECTIVE COMPLEX TO THE
NORTHWEST OF THE REGION WILL BE ONGOING THIS EVENING. SURFACE LOW
WILL CONTINUE TO STRENGTHEN AS IT MOVES INTO THE WESTERN GREAT LAKES
BY LATE EVENING. WHILE CONVECTIVE FEEDBACK MAY BE CONTRIBUTING TO AN
OVERESTIMATION IN THE LOW LEVEL WIND FIELDS...OVERALL DYNAMICS ARE
EXTREMELY IMPRESSIVE FOR AN EARLY SUMMER SYSTEM. SUB 1000MB WAVES
WILL GET YOUR ATTENTION THIS TIME OF YEAR...LET ALONE THE
POSSIBILITY OF A SURFACE LOW INTENSITY IN THE VICINITY OF 990-995MB
BY THE EARLY OVERNIGHT OVER THE GREAT LAKES AS BEING ADVERTISED.
CONSIDERING THE AVAILABLE HIGH INSTABILITY TO GO ALONG WITH THE
PROGGED WIND FIELDS...FURTHER GROWTH IN AREAL COVERAGE AND INTENSITY
TO CONVECTION IS ANTICIPATED THROUGH THE EVENING.
WHILE MUCH GREATER CERTAINTY EXISTS WITH RESPECT TO POTENTIAL FOR
SEVERE CONVECTION OVER THE WESTERN GREAT LAKES...THE PICTURE IS NOT
AS CLEAR FOR CENTRAL INDIANA. INITIALLY...MODEL SOUNDINGS INDICATE
THE CAP STILL PRESENT THROUGH THE EVENING WITH COOLING ALOFT TOWARDS
06Z AS MID LEVEL HEIGHTS TUMBLE. CORE OF THE HIGHER WIND FIELDS AND
FORCING ALOFT WILL PASS TO THE NORTH OF THE FORECAST AREA
OVERNIGHT...BUT THE LOW LEVEL JET WILL PROVIDE A GLANCING BLOW WITH
850MB WINDS PEAKING AT 35-40KTS OVER NORTHERN COUNTIES AROUND 06Z.
WHILE THE ENVIRONMENT WILL NOT BE AS CONDUCIVE TO MAINTAINING THE
DEGREE OF CONVECTIVE INTENSITY...FEEL THE STRONGER LOW LEVEL WIND
FIELDS ALONG WITH PLENTY OF INSTABILITY PRESENT SHOULD BE MORE THAN
SUFFICIENT FOR STORMS TO MAKE IT INTO THE FORECAST AREA AROUND OR
SHORTLY AFTER MIDNIGHT. HI-RES NMM/ARW SUPPORT THIS THINKING...BOTH
INDICATING A WEAKENING SQUALL LINE IMPACTING NORTHWEST HALF OF THE
FORECAST AREA BETWEEN 06-09Z. MAIN IMPACTS FROM THE LINE BESIDES
TORRENTIAL RAINS WOULD BE DAMAGING WINDS AS A WELL DEVELOPED COLD
POOL LIKELY TO ACCOMPANY THE STORMS. HAVE FOCUSED HIGHEST POPS
MAINLY ALONG AND NORTH OF I-70 WITH LOWER POPS FURTHER SOUTH. VERY
POSSIBLE THAT SOUTHERN PORTIONS OF THE FORECAST AREA SEE NO RAIN AT
ALL.
LOW PRESSURE WILL LIFT OUT INTO QUEBEC ON TUESDAY LEAVING THE
REMNANT FRONTAL BOUNDARY OVER THE REGION. PRESENCE OF THE FRONT
ALONG WITH ANY LEFTOVER OUTFLOW BOUNDARIES FROM CONVECTION TONIGHT
MAY SERVE TO INITIATE NEW STORMS AS HEATING PEAKS TUESDAY
AFTERNOON...ESPECIALLY ACROSS THE SOUTHERN HALF OF THE FORECAST
AREA. HOWEVER IN THE ABSENCE OF MORE SUBSTANTIAL FORCING
ALOFT...HAVE LOW CONFIDENCE IN HOW EXTENSIVE THE COVERAGE WILL BE.
WILL CARRY ONLY ISOLATED POPS AT THIS TIME WITH MAINLY DRY WEATHER
TUESDAY NIGHT AS THE FRONT SHIFTS SOUTH OF THE OHIO RIVER.
UPPER TROUGH WILL REMAIN ACROSS THE GREAT LAKES INTO WEDNESDAY WITH
ANOTHER WAVE ALOFT ROTATING THROUGH THE REGION ALONG WITH A
SECONDARY FRONT. WHILE BETTER INSTABILITY WILL BE DISPLACED TO THE
SOUTH OF THE FORECAST AREA CLOSER TO THE MAIN FRONT...EXPECT
SCATTERED CONVECTIVE DEVELOPMENT FOCUSED ON WEDNESDAY AFTERNOON AND
EVENING. HIGH PRESSURE WILL BUILD IN WEDNESDAY NIGHT WITH COOLER AND
MUCH DRIER WEATHER...FINALLY GIVING CENTRAL INDIANA A BREAK FROM THE
UNSETTLED...STORMY AND HUMID WEATHER EXPERIENCED OVER THE LAST FEW
WEEKS.
TEMPS...LOW LEVEL THERMAL PROFILES ARE GENERALLY SIMILAR TO TODAY ON
TUESDAY...ESPECIALLY SOUTH OF I-70. ONCE AGAIN TRENDED TOWARDS
WARMER METMOS GUIDANCE WITH HIGHS IN THE MID/UPPER 80S. WENT A FEW
DEGREES ABOVE MAVMOS FOR WEDNESDAY AS THE 00Z GFS LOOKS OVERLY
AGGRESSIVE WITH BRINGING THE COOLER AIR INTO THE REGION...ESPECIALLY
WITH THE SECONDARY BOUNDARY AND UPPER WAVE IN THE AREA. PREFERRED
WARMER METMOS FOR OVERNIGHT LOWS THROUGH THE PERIOD. LOWS BY
WEDNESDAY NIGHT IN THE UPPER 50S/LOWER 60S WILL FEEL WONDERFUL.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
ISSUED AT 325 AM EDT MON JUN 30 2014
SURFACE HIGH PRESSURE MOVES THROUGH CENTRAL INDIANA DURING THE LONG
TERM. THIS WILL BRING DRY WEATHER WITH IT THROUGH MUCH OF THE PERIOD
ALONG WITH BELOW NORMAL TEMPERATURES FOR THE END OF THE WEEK.
NORTHERLY COMPONENT FLOW WILL USHER IN COOLER TEMPERATURES AND DRIER
DEW POINTS FOR THURSDAY AND FRIDAY WITH SATURDAY AND SUNDAY CLIMBING
BACK INTO THE LOW 80S AS THE HIGH PRESSURE CENTER MOVES TO THE EAST
AND SOUTHWESTERLY FLOW COMMENCES ON THE BACK SIDE. SUNDAY GFS AND
ECMWF ARE BOTH SHOWING A SHORTWAVE APPROACHING SO COULD SEE PRECIP
CHANCES ARRIVING AFTER THAT. PRIOR TO SUNDAY THOUGH MODELS ARE IN
GOOD AGREEMENT ON A DRY FORECAST.
&&
.AVIATION /DISCUSSION FOR 301200Z TAF ISSUANCE/...
ISSUED AT 702 AM EDT MON JUN 30 2014
SITES ARE STARTING OUT WITH MVFR CEILINGS AND EXPECT THIS TO
CONTINUE FOR A FEW HOURS BEFORE THEY SHOULD LIFT TO VFR. A
THUNDERSTORM COMPLEX CURRENTLY ACROSS NORTH CENTRAL ILLINOIS LOOKS
LIKE IT WILL HOLD TOGETHER TO IMPACT KLAF BEFORE FIZZLING OUT TO
SHOWERS. HRRR AND RAP DO NOT SHOW IT HOLDING TOGETHER EVEN THAT LONG
BUT RECENT RADAR TRENDS POINT OTHERWISE. THUS WILL TEMPO IN SOME
THUNDER AT KLAF TIMED TO MATCH CURRENT OBSERVATIONAL TRENDS. AT KHUF
WILL PUT IN SOME VCSH AS THERE IS NO LIGHTNING WITH THE ECHOES
HEADING THAT WAY. DOES NOT CURRENTLY LOOK LIKE THIS WILL IMPACT KIND
AND KBMG. ANOTHER ROUND OF STORMS SHOULD MOVE IN FROM THE NORTHWEST
TONIGHT BUT TIMING IS STILL A BIT IN THE AIR. WILL PUT IN A VCTS
DURING MOST LIKELY TIMEFRAME TO INDICATE CONVECTIVE POTENTIAL.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM...CP
AVIATION...CP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
704 AM EDT MON JUN 30 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 325 AM EDT MON JUN 30 2014
THE APPROACH AND PASSAGE OF A STRONG COLD FRONT WILL BRING THE
CHANCE FOR THUNDERSTORMS THROUGH WEDNESDAY. THE GREATEST THREAT FOR
SEVERE WEATHER WILL EXIST TONIGHT INTO EARLY TUESDAY AS AN
INTENSIFYING LOW PRESSURE PASSES TO THE NORTH OF THE REGION.
CANADIAN HIGH PRESSURE WILL BUILD SOUTH INTO THE OHIO VALLEY BY
WEDNESDAY NIGHT...FINALLY PROVIDING A BREAK FROM THE RECENT STORMY
PATTERN. DRY PLEASANT WEATHER IS EXPECTED FOR MUCH OF THE HOLIDAY
WEEKEND.
&&
.NEAR TERM /TODAY/...
ISSUED AT 325 AM EDT MON JUN 30 2014
WEAK RIDGING ALOFT HAS BUILT INTO CENTRAL INDIANA EARLY THIS MORNING
RESULTING IN MAINLY CLEAR SKIES FOR THE MOMENT AND QUIET WEATHER SO
FAR. MUGGY AIRMASS ACROSS THE REGION WITH TEMPS MAINLY IN THE LOWER
70S AS OF 07Z.
INTERESTING 18 TO 24 HOURS UPCOMING FOR THE MIDWEST WITH AN
ANOMALOUSLY STRONG UPPER LOW DRIFTING INTO WESTERN ONTARIO AND
SEVERAL WAVES ALOFT ROTATING AROUND THE BASE OF THE TROUGH IN A FAST
ZONAL FLOW FROM THE CENTRAL PLAINS E/NE INTO THE GREAT LAKES.
ONGOING CONVECTIVE CLUSTER OVER NORTHERN ILLINOIS/EASTERN IOWA THIS
MORNING AND EXPECTED DEVELOPMENT LATER TODAY AS A STRONG SURFACE
WAVE EJECTS OUT OF THE CENTRAL PLAINS.
INITIAL ISSUE IS AFOREMENTIONED STORM CLUSTER MOVING THROUGH
NORTHERN ILLINOIS. STORMS ARE BEING FED BY A 40KT LOW LEVEL JET
TRANSPORTING RICH TROPICAL MOISTURE INTO THE MID MISSISSIPPI VALLEY.
MESOANALYSIS ALSO INDICATING THE ACTIVITY PROPAGATING ALONG AN
INSTABILITY AXIS AND THETA-E RIDGE. BULK OF THE SHORT RANGE MODEL
GUIDANCE GRADUALLY WEAKENS THE COMPLEX OVER THE NEXT 4-6 HOURS AS IT
TRACKS E/SE AWAY FROM THE DEEPER INSTABILITY AND MOISTURE. ALREADY
SEEING WARMING CLOUD TOPS ON THE SOUTHERN EDGE OF THE COMPLEX AS
STORMS INTERACT WITH WARMER MID LEVEL TEMPS WITH THE PREDOMINANT
FOCUS SHIFTING TO THE CONVECTION WEST OF CHICAGO IN THE VICINITY OF
THE BEST FORCING ALOFT AND INSTABILITY. WHILE STORMS WILL WEAKEN AS
THEY MOVE EAST...NOT COMPLETELY OUT OF THE QUESTION THAT PRECIP MAY
MAKE IT TO THE NORTHERN WABASH VALLEY BEFORE DIMINISHING AROUND OR
SHORTLY AFTER SUNRISE. OF GREATER IMPACT TO THE FORECAST AREA WILL
BE LEFTOVER CLOUD DEBRIS FROM THE COMPLEX WHICH IS LIKELY TO LIMIT
SURFACE HEATING THIS MORNING. WITH RISING 500MB HEIGHTS AS THE RIDGE
TO THE SOUTH FLEXES ITS MUSCLES HOWEVER...ANTICIPATE MOST OF THE
DEBRIS WILL BE GONE BY MIDDAY.
AFTERNOON SHOULD BE LARGELY QUIET FOR CENTRAL INDIANA AS THE WARMING
TEMPS ALOFT PROMOTE A CAP AROUND 700MB. WILL LEAVE A 20 POP IN FOR
ANY ISOLATED CONVECTION AS A WEAK WAVE ALOFT DRIFTS THROUGH THE
REGION DURING THE EARLY AFTERNOON...BUT THE CAP SHOULD KEEP A LID ON
MOST STORMS. FOCUS WILL SHIFT BACK TO NEBRASKA AND IOWA BY MID
AFTERNOON AS THE ARRIVAL OF A STRENGTHENING SURFACE LOW INTO AN
INCREASINGLY UNSTABLE ENVIRONMENT WILL SET THE STAGE FOR WIDESPREAD
ROBUST CONVECTIVE DEVELOPMENT FOR THE SECOND HALF OF THE
AFTERNOON...WITH STORMS RAPIDLY EXPANDING EAST INTO NORTHERN
ILLINOIS AND WISCONSIN BY EARLY EVENING. MORE ON POTENTIAL IMPACTS
TO OUR FORECAST AREA IN THE SHORT TERM SECTION.
TEMPS...DESPITE 850MB TEMPS RISING TO AROUND 20C BY LATE
AFTERNOON...CLOUD DEBRIS THIS MORNING AND CU DURING THE AFTERNOON
WILL LIMIT HEATING SLIGHTLY. LEANED TOWARDS WARMER METMOS WITH MUCH
OF THE FORECAST AREA WARMING TO 86-89.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
ISSUED AT 325 AM EDT MON JUN 30 2014
FORECAST CHALLENGES FOCUS PRIMARILY ON PRECIP CHANCES TONIGHT...AS
WELL AS TEMPS AND PRECIP CHANCES THROUGHOUT THE REMAINDER OF THE
SHORT TERM.
WELL DEVELOPED AND INTENSIFYING MESOSCALE CONVECTIVE COMPLEX TO THE
NORTHWEST OF THE REGION WILL BE ONGOING THIS EVENING. SURFACE LOW
WILL CONTINUE TO STRENGTHEN AS IT MOVES INTO THE WESTERN GREAT LAKES
BY LATE EVENING. WHILE CONVECTIVE FEEDBACK MAY BE CONTRIBUTING TO AN
OVERESTIMATION IN THE LOW LEVEL WIND FIELDS...OVERALL DYNAMICS ARE
EXTREMELY IMPRESSIVE FOR AN EARLY SUMMER SYSTEM. SUB 1000MB WAVES
WILL GET YOUR ATTENTION THIS TIME OF YEAR...LET ALONE THE
POSSIBILITY OF A SURFACE LOW INTENSITY IN THE VICINITY OF 990-995MB
BY THE EARLY OVERNIGHT OVER THE GREAT LAKES AS BEING ADVERTISED.
CONSIDERING THE AVAILABLE HIGH INSTABILITY TO GO ALONG WITH THE
PROGGED WIND FIELDS...FURTHER GROWTH IN AREAL COVERAGE AND INTENSITY
TO CONVECTION IS ANTICIPATED THROUGH THE EVENING.
WHILE MUCH GREATER CERTAINTY EXISTS WITH RESPECT TO POTENTIAL FOR
SEVERE CONVECTION OVER THE WESTERN GREAT LAKES...THE PICTURE IS NOT
AS CLEAR FOR CENTRAL INDIANA. INITIALLY...MODEL SOUNDINGS INDICATE
THE CAP STILL PRESENT THROUGH THE EVENING WITH COOLING ALOFT TOWARDS
06Z AS MID LEVEL HEIGHTS TUMBLE. CORE OF THE HIGHER WIND FIELDS AND
FORCING ALOFT WILL PASS TO THE NORTH OF THE FORECAST AREA
OVERNIGHT...BUT THE LOW LEVEL JET WILL PROVIDE A GLANCING BLOW WITH
850MB WINDS PEAKING AT 35-40KTS OVER NORTHERN COUNTIES AROUND 06Z.
WHILE THE ENVIRONMENT WILL NOT BE AS CONDUCIVE TO MAINTAINING THE
DEGREE OF CONVECTIVE INTENSITY...FEEL THE STRONGER LOW LEVEL WIND
FIELDS ALONG WITH PLENTY OF INSTABILITY PRESENT SHOULD BE MORE THAN
SUFFICIENT FOR STORMS TO MAKE IT INTO THE FORECAST AREA AROUND OR
SHORTLY AFTER MIDNIGHT. HI-RES NMM/ARW SUPPORT THIS THINKING...BOTH
INDICATING A WEAKENING SQUALL LINE IMPACTING NORTHWEST HALF OF THE
FORECAST AREA BETWEEN 06-09Z. MAIN IMPACTS FROM THE LINE BESIDES
TORRENTIAL RAINS WOULD BE DAMAGING WINDS AS A WELL DEVELOPED COLD
POOL LIKELY TO ACCOMPANY THE STORMS. HAVE FOCUSED HIGHEST POPS
MAINLY ALONG AND NORTH OF I-70 WITH LOWER POPS FURTHER SOUTH. VERY
POSSIBLE THAT SOUTHERN PORTIONS OF THE FORECAST AREA SEE NO RAIN AT
ALL.
LOW PRESSURE WILL LIFT OUT INTO QUEBEC ON TUESDAY LEAVING THE
REMNANT FRONTAL BOUNDARY OVER THE REGION. PRESENCE OF THE FRONT
ALONG WITH ANY LEFTOVER OUTFLOW BOUNDARIES FROM CONVECTION TONIGHT
MAY SERVE TO INITIATE NEW STORMS AS HEATING PEAKS TUESDAY
AFTERNOON...ESPECIALLY ACROSS THE SOUTHERN HALF OF THE FORECAST
AREA. HOWEVER IN THE ABSENCE OF MORE SUBSTANTIAL FORCING
ALOFT...HAVE LOW CONFIDENCE IN HOW EXTENSIVE THE COVERAGE WILL BE.
WILL CARRY ONLY ISOLATED POPS AT THIS TIME WITH MAINLY DRY WEATHER
TUESDAY NIGHT AS THE FRONT SHIFTS SOUTH OF THE OHIO RIVER.
UPPER TROUGH WILL REMAIN ACROSS THE GREAT LAKES INTO WEDNESDAY WITH
ANOTHER WAVE ALOFT ROTATING THROUGH THE REGION ALONG WITH A
SECONDARY FRONT. WHILE BETTER INSTABILITY WILL BE DISPLACED TO THE
SOUTH OF THE FORECAST AREA CLOSER TO THE MAIN FRONT...EXPECT
SCATTERED CONVECTIVE DEVELOPMENT FOCUSED ON WEDNESDAY AFTERNOON AND
EVENING. HIGH PRESSURE WILL BUILD IN WEDNESDAY NIGHT WITH COOLER AND
MUCH DRIER WEATHER...FINALLY GIVING CENTRAL INDIANA A BREAK FROM THE
UNSETTLED...STORMY AND HUMID WEATHER EXPERIENCED OVER THE LAST FEW
WEEKS.
TEMPS...LOW LEVEL THERMAL PROFILES ARE GENERALLY SIMILAR TO TODAY ON
TUESDAY...ESPECIALLY SOUTH OF I-70. ONCE AGAIN TRENDED TOWARDS
WARMER METMOS GUIDANCE WITH HIGHS IN THE MID/UPPER 80S. WENT A FEW
DEGREES ABOVE MAVMOS FOR WEDNESDAY AS THE 00Z GFS LOOKS OVERLY
AGGRESSIVE WITH BRINGING THE COOLER AIR INTO THE REGION...ESPECIALLY
WITH THE SECONDARY BOUNDARY AND UPPER WAVE IN THE AREA. PREFERRED
WARMER METMOS FOR OVERNIGHT LOWS THROUGH THE PERIOD. LOWS BY
WEDNESDAY NIGHT IN THE UPPER 50S/LOWER 60S WILL FEEL WONDERFUL.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
ISSUED AT 325 AM EDT MON JUN 30 2014
SURFACE HIGH PRESSURE MOVES THROUGH CENTRAL INDIANA DURING THE LONG
TERM. THIS WILL BRING DRY WEATHER WITH IT THROUGH MUCH OF THE PERIOD
ALONG WITH BELOW NORMAL TEMPERATURES FOR THE END OF THE WEEK.
NORTHERLY COMPONENT FLOW WILL USHER IN COOLER TEMPERATURES AND DRIER
DEW POINTS FOR THURSDAY AND FRIDAY WITH SATURDAY AND SUNDAY CLIMBING
BACK INTO THE LOW 80S AS THE HIGH PRESSURE CENTER MOVES TO THE EAST
AND SOUTHWESTERLY FLOW COMMENCES ON THE BACK SIDE. SUNDAY GFS AND
ECMWF ARE BOTH SHOWING A SHORTWAVE APPROACHING SO COULD SEE PRECIP
CHANCES ARRIVING AFTER THAT. PRIOR TO SUNDAY THOUGH MODELS ARE IN
GOOD AGREEMENT ON A DRY FORECAST.
&&
.AVIATION /DISCUSSION FOR 301200Z TAF ISSUANCE/...
ISSUED AT 702 AM EDT MON JUN 30 2014
SITES ARE STARTING OUT WITH MVFR CEILINGS AND EXPECT THIS TO
CONTINUE FOR A FEW HOURS BEFORE THEY SHOULD LIFT TO VFR. A
THUNDERSTORM COMPLEX CURRENTLY ACROSS NORTH CENTRAL ILLINOIS LOOKS
LIKE IT WILL HOLD TOGETHER TO IMPACT KLAF BEFORE FIZZLING OUT TO
SHOWERS. HRRR AND RAP DO NOT SHOW IT HOLDING TOGETHER EVEN THAT LONG
BUT RECENT RADAR TRENDS POINT OTHERWISE. THUS WILL TEMPO IN SOME
THUNDER AT KLAF TIMED TO MATCH CURRENT OBSERVATIONAL TRENDS. AT KHUF
WILL PUT IN SOME VCSH AS THERE IS NO LIGHTNING WITH THE ECHOES
HEADING THAT WAY. DOES NOT CURRENTLY LOOK LIKE THIS WILL IMPACT KIND
AND KBMG. ANOTHER ROUND OF STORMS SHOULD MOVE IN FROM THE NORTHWEST
TONIGHT BUT TIMING IS STILL A BIT IN THE AIR. WILL PUT IN A VCTS
DURING MOST LIKELY TIMEFRAME TO INDICATE CONVECTIVE POTENTIAL.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM....CP
AVIATION...CP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS TOPEKA KS
541 AM CDT Mon Jun 30 2014
...AVIATION UPDATE...
.SHORT TERM...(Today and Tonight)
Issued at 340 AM CDT MON JUN 30 2014
08Z profiler data shows the low level jet of 30 to 40 KTS continues
to gradually veer to the southwest becoming more parallel to the
front across central NEB. Meanwhile, water vapor imagery shows a
shortwave rotating through ID and MT with nearly zonal flow from the
west coast into the central plains. Surface obs indicate a very warm
and moist airmass remains in place across the forecast area.
With the low level jet veering southwest, convergence along the
boundary is likely to diminish. Besides that any convergence along
the boundary for elevated storms should remain to the north of the
area. Therefore think much of the nocturnal precip will remain north
of the forecast area. Will keep a token slight chance across the
northern tier of counties as the light shower activity spreads east.
The shortwave rotating through the mean flow over the northern
plains is expected to help push the cold front south into the area
by this afternoon. With the front lifting a very moist and unstable
airmass, thunderstorms are likely to develop in eastern KS before
moving to the east. Deep layer shear is expected to be sufficient
for supercell storms and low level shear and LCL heights suggest
tornadoes will be possible. The main questions are how widespread
the convection may be and when storms could initiate. Models show a
low level cap over the warm sector around 850 MB until late in the
afternoon, not unlike what was observed yesterday. But eventually
the forecast soundings cool the layer removing any inhibition. It is
unclear as to where the cooling is coming from as winds within the
layer remain from the southwest. Additionally the stronger forcing
associated with the shortwave over the northern plains appears to
remain just north of the forecast area. So am concerned that these
two factors may limit the coverage of storms in the later afternoon
and early evening. Nevertheless any storm that forms could quickly
become severe with a potential for tornadoes due to the instability
greater than 4000 J/kg and shear progged by the models. At this
time, think thunderstorm initiation may occur over eastern KS with
storms moving to the east. The thunderstorm activity is expected to
push south through the night tonight as the front slowly moves
south.
Highs today should be several degrees warmer than yesterday as there
should be less high level clouds to start the day off and models
laying the thermal ridge over into northeast KS along the surface
trough. There is some uncertainty in how deep the boundary layer
will mix and in turn how warm temps will get. The RAP has had a bias
to mixing the boundary layer to deep and feel it is way to warm.
Since there is so much humidity in the air, opted to keep highs in
the lower and middle 90s. This humidity however will cause heat
indices to range from 100 to 105 this afternoon. If it looks like
temps could end up a degree or two warmer with dewpoints holding in
the 70s, a heat advisory may be needed. Lows tonight should fall
into the 60s with some drier air advecting in from the north along
with some weak cold air advection.
.LONG TERM...(Tuesday through Sunday)
Issued at 340 AM CDT MON JUN 30 2014
The previous active days will begin to calm for next week as a
cooler and more stable airmass settles into place. Still maintained
slight chances for thunderstorms Tuesday with the h85 front across
southern Kansas. Best chances for precipitation will reside near the
Kansas and Oklahoma border. Dry northwest flow aloft continues
Wednesday and Thursday as an expansive surface high builds from the
central plains through the Great Lakes. Light northerly sfc winds
around 10 mph Tuesday gradually will shift to the east and southeast
on Friday as the ridge nudges eastward. Upper ridging begins to
break down, tracking a shortwave trough into the central plains on
Friday evening. Mentioned slight chances for thunderstorms over the
northern CWA at this time, where highest lift resides. Confidence
however, in the southward extent to the trough is low at this time.
Periodic thunderstorms may be possible for next weekend as mid level
flow begins quasi-zonal, allowing for weak waves to pass through.
Unseasonably cooler temperatures Tuesday through Thursday, combined
with dewpoint temperatures in the 50s will make it feel much more
pleasant compared to the previous days. Highs behind the front
Tuesday begin in the low to middle 80s. Weak cool advection with the
surface ridge sliding south will lower highs Wednesday and Thursday
to the upper 70s and lower 80s. Overnight lows during this time with
decent radiational cooling and light winds may reach the upper 50s.
Thermal ridge begins to build over western and central KS
Independence Day as southerly flow returns, peaking highs to the low
and middle 80s. Weekend temps are track to return to near 90 degrees
with overnight lows in the upper 60s.
&&
.AVIATION...(For the 12Z TAFs through 12Z Tuesday Morning)
Issued at 541 AM CDT MON JUN 30 2014
Main uncertainty in forecast is whether a low level cap will limit
storm coverage to a few isolated storms or if a broken line of
storms will form along the front. Because of this have only
maintained a VCTS in the forecast as the front moves through. IFR
conditions would be likely if a TS where to move into the
terminals. Otherwise good mixing of the boundary layer is expected
to keep VFR conditions this morning. Some modest dry air advection
behind the front overnight should allow VFR conditions to persist
into Tuesday morning.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...Wolters
LONG TERM...Bowen
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS GRAY ME
933 AM EDT MON JUN 30 2014
.SYNOPSIS...
HIGH PRESSURE SHIFTS OFFSHORE WHICH WILL INTRODUCE MORE HUMID AIR
TO THE REGION...ALONG WITH A CHANCE FOR SCATTERED AFTERNOON
SHOWERS AND THUNDERSTORMS TODAY AND TUESDAY. A COLD FRONT WILL
TRY TO PUSH THROUGH THE AREA MID TO LATE WEEK AND WILL BE THE
FOCUS FOR THUNDERSTORM ACTIVITY...ESPECIALLY WEDNESDAY AND
THURSDAY. LOW PRESSURE WILL MOVE UP THE MID ATLANTIC COAST ON
FRIDAY...BEFORE PASSING OUT TO SEA OVER THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
930AM UPDATE...WEAKENING SURFACE TROUGH WILL MOVE THROUGH THE REGION
TODAY. EARLIER SHOWERS ACROSS ME MOUNTAINS HAVE DRIED UP. THERE
ARE CURRENTLY SOME SHOWERS ASSOCIATED WITH THE TROUGH ACROSS NY
AND VT. AS THE TROUGH MOVES EASTWARD THE ATMOSPHERE IS A BIT MORE
STABLE WITH A CAP AT ABOUT 700 MB. SCATTERED SHOWERS/TSTMS
ARE POSSIBLE THIS AFTERNOON ACROSS WESTERN NH...AND THE MOUNTAINS
OF NH AND WESTERN ME...OTHERWISE MOSTLY DRY WEATHER. CURRENT FCST
HAS A GOOD HANDLE ON SITUATION. NO SIGNIFICANT CHANGES EXPECTED.
UPDATE...A FEW TWEAKS BASED ON CURRENT OBSERVATIONAL TRENDS. HAVE
BUMPED CLOUD COVER AND MOVED TIMING OF ISOLD SHRA UP IN THE MTNS
BASED ON LATEST RADAR/SATELLITE COMBINATION.
PREVIOUS DISCUSSION...RIDGE BUILDING INTO THE AREA ATTM...WITH
MOSTLY CLEAR SKIES AND MILDER TEMPS. SFC HIGH PRES HAS SLIPPED
EWD...ALLOWING SWLY FLOW TO SET UP OVER THE AREA. THIS WILL
INCREASE BOTH HEAT AND HUMIDITY FOR TODAY. SHOULD SEE READINGS
WELL INTO THE 80S AGAIN FOR MUCH OF THE AREA...AS WELL AS A
NOTABLE UPTICK IN DEWPOINTS MAKING THINGS A BIT MORE UNCOMFORTABLE
AWAY FROM THE WATER.
DESPITE UPPER RIDGE OVERHEAD...MODEL GUIDANCE HAS BEEN CONSISTENT
IN PASSING A WEAK DISTURBANCE THRU IT THIS AFTERNOON. FORCING IS
SUBTLE...SO DO NOT ANTICIPATE MUCH MORE THAN WIDELY SCT
SHRA/TSTMS...BUT DO EXPECT THERE TO BE SOME CONVECTION IN THE
HIGHER TERRAIN TODAY. HRRR AND HI-RES CONVECTION ALLOWING MODEL
GUIDANCE ARE ON BOARD WITH THIS THOUGHT AS WELL. WE WILL HAVE THE
HEAT AND HUMIDITY AS FUEL...BUT FLOW IS QUITE WEAK WITHIN THE
RIDGE. SO ANY STORMS WILL BE SLOW MOVING...WITH LOCALLY HEAVY
RNFL BEING THE MAIN THREAT. THE MAIN CULPRIT WILL BE SLOW STORM
MOTIONS...AS PWAT VALUES ARE NOT FORECAST TO BE ABOVE NORMAL
TODAY. IN ADDITION WARM CLOUD DEPTHS ARE FAIRLY LOW...NOT
APPROACHING 10 KFT UNTIL LATE IN THE DAY.
&&
.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
TONIGHT SWLY FLOW WILL CONTINUE. MODEL GUIDANCE IS GROWING
INCREASINGLY AGGRESSIVE IN DEVELOPING COASTAL FOG/STRATUS FOR THE
OVERNIGHT. I FEEL THAT NWP MAY BE RUSHING THINGS JUST A BIT.
DEWPOINT DEPRESSIONS DON/T APPROACH ZERO UNTIL TUE NIGHT...WHICH
WOULD FAVOR BETTER FOG CHANCES THEN. WILL HAVE SOME PATCHY FOG
TONIGHT WHERE RH VALUES ARE GREATER THAN 95 PERCENT OVER THE
WATERS.
TRIPLE H KIND OF DAY IN STORE FOR MUCH OF THE AREA TUE. SW FLOW
WARM SPOTS OF SRN NH ESPECIALLY SHOULD EXCEED 90 DEGREES.
DEWPOINTS WELL INTO THE 60S WILL ADD TO THE DISCOMFORT. ALSO HAVE
LESS POP TUE THAN TODAY. CWFA SHOULD BE FIRMLY WITHIN THE UPPER
RIDGE BY THEN...WITH MODEL GUIDANCE CONSISTENT AND IN AGREEMENT
THAT LITTLE IN THE WAY OF FORCING WILL BE IN PLACE. FARTHER W IN
NY STATE CONVECTION SHOULD BE ONGOING...POSSIBLY STRONG...AND THIS
COULD SPILL OVER INTO WRN ZONES AS IT DECAYS.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
WEAKENING COLD FRONT WILL CONTINUE TO BRING SOME SCATTERED PRECIP
IN THE FORM OF SHOWERS AND SCATTERED THUNDERSTORMS ACROSS
NORTHERN NEW ENGLAND. BY THURSDAY...00Z MODEL SUITE IN GOOD
AGREEMENT WITH THE SURFACE FRONT BECOMING NEARLY STATIONARY OVER
OUR REGION. THIS INCREASES POPS AND WILL MOVE INTO THE LIKELY
CATEGORY THROUGH THURSDAY NIGHT DURING THIS PACKAGE UPDATE.
ON FRIDAY...A SYSTEM WILL MOVE UP THE MID ATLANTIC REGION. LATEST
EURO MODEL RUN DEEPENS THIS LOW RAPIDLY AS IT PASSES TO OUR EAST.
LITTLE IF ANY PRECIP EXPECTED WITH THE PASSAGE OF THIS
SYSTEM...HOWEVER SWELLS WILL BE ON THE INCREASE LATE IN THE
FORECAST PERIOD...LEADING TO ENHANCED RIP RISK.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
SHORT TERM...MAINLY VFR CONDITIONS TO PREVAIL THRU TUE. A WEAK
DISTURBANCE SHOULD LEAD TO WIDELY SCT SHRA/TSTMS THIS
AFTERNOON...WHICH COULD LEAD TO LOCAL MVFR OR LOWER CONDITIONS IN
THE MTNS. MODEL GUIDANCE IS FAIRLY AGGRESSIVE IN DEVELOPING
COASTAL FOG/STRATUS TONIGHT...BUT NOT CONFIDENT ENOUGH YET TO
INCLUDE IN TAFS.
LONG TERM...MAINLY VFR CONDITIONS EXPECTED. LOCAL MVFR OR LOWER
CONDITIONS POSSIBLE IN SHRA OR TSRA...ESPECIALLY THU INTO EARLY
FRI.
&&
.MARINE...
SHORT TERM...SW FLOW HAS ALREADY DEVELOPED OVER THE WATERS THIS
MORNING. COLD WATER TEMPS WILL SUPPORT A SHALLOW INVERSION WHICH
SHOULD LIMIT GUST POTENTIAL. EXPECT ANY GUSTS TO REMAIN BELOW 25
KTS. SEAS WILL GRADUALLY BUILD THRU TUE...AND A SCA FOR HAZARDOUS
SEAS MAY BE NECESSARY BY TUE.
LONG TERM...SLOWLY ADVANCING TROF WILL SET UP LONG DURATION
SOUTHWESTERLY FLOW OVER THE WATERS FOR MUCH OF THE WEEK. WIND FETCH
SHOULD EVENTUALLY ALLOW SEAS TO BUILD TO AT LEAST 5 FEET. LONG
PERIOD SWELLS MAY ARRIVE WITH AN OFFSHORE SYSTEM OVER THE WEEKEND.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...JENSENIUS
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
723 AM EDT MON JUN 30 2014
.SYNOPSIS...
HIGH PRESSURE SHIFTS OFFSHORE WHICH WILL INTRODUCE MORE HUMID AIR
TO THE REGION...ALONG WITH A CHANCE FOR SCATTERED AFTERNOON
SHOWERS AND THUNDERSTORMS TODAY AND TUESDAY. A COLD FRONT WILL
TRY TO PUSH THROUGH THE AREA MID TO LATE WEEK AND WILL BE THE
FOCUS FOR THUNDERSTORM ACTIVITY...ESPECIALLY WEDNESDAY AND
THURSDAY. LOW PRESSURE WILL MOVE UP THE MID ATLANTIC COAST ON
FRIDAY...BEFORE PASSING OUT TO SEA OVER THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE...A FEW TWEAKS BASED ON CURRENT OBSERVATIONAL TRENDS. HAVE
BUMPED CLOUD COVER AND MOVED TIMING OF ISOLD SHRA UP IN THE MTNS
BASED ON LATEST RADAR/SATELLITE COMBINATION.
PREVIOUS DISCUSSION...RIDGE BUILDING INTO THE AREA ATTM...WITH
MOSTLY CLEAR SKIES AND MILDER TEMPS. SFC HIGH PRES HAS SLIPPED
EWD...ALLOWING SWLY FLOW TO SET UP OVER THE AREA. THIS WILL
INCREASE BOTH HEAT AND HUMIDITY FOR TODAY. SHOULD SEE READINGS
WELL INTO THE 80S AGAIN FOR MUCH OF THE AREA...AS WELL AS A
NOTABLE UPTICK IN DEWPOINTS MAKING THINGS A BIT MORE UNCOMFORTABLE
AWAY FROM THE WATER.
DESPITE UPPER RIDGE OVERHEAD...MODEL GUIDANCE HAS BEEN CONSISTENT
IN PASSING A WEAK DISTURBANCE THRU IT THIS AFTERNOON. FORCING IS
SUBTLE...SO DO NOT ANTICIPATE MUCH MORE THAN WIDELY SCT
SHRA/TSTMS...BUT DO EXPECT THERE TO BE SOME CONVECTION IN THE
HIGHER TERRAIN TODAY. HRRR AND HI-RES CONVECTION ALLOWING MODEL
GUIDANCE ARE ON BOARD WITH THIS THOUGHT AS WELL. WE WILL HAVE THE
HEAT AND HUMIDITY AS FUEL...BUT FLOW IS QUITE WEAK WITHIN THE
RIDGE. SO ANY STORMS WILL BE SLOW MOVING...WITH LOCALLY HEAVY
RNFL BEING THE MAIN THREAT. THE MAIN CULPRIT WILL BE SLOW STORM
MOTIONS...AS PWAT VALUES ARE NOT FORECAST TO BE ABOVE NORMAL
TODAY. IN ADDITION WARM CLOUD DEPTHS ARE FAIRLY LOW...NOT
APPROACHING 10 KFT UNTIL LATE IN THE DAY.
&&
.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
TONIGHT SWLY FLOW WILL CONTINUE. MODEL GUIDANCE IS GROWING
INCREASINGLY AGGRESSIVE IN DEVELOPING COASTAL FOG/STRATUS FOR THE
OVERNIGHT. I FEEL THAT NWP MAY BE RUSHING THINGS JUST A BIT.
DEWPOINT DEPRESSIONS DON/T APPROACH ZERO UNTIL TUE NIGHT...WHICH
WOULD FAVOR BETTER FOG CHANCES THEN. WILL HAVE SOME PATCHY FOG
TONIGHT WHERE RH VALUES ARE GREATER THAN 95 PERCENT OVER THE
WATERS.
TRIPLE H KIND OF DAY IN STORE FOR MUCH OF THE AREA TUE. SW FLOW
WARM SPOTS OF SRN NH ESPECIALLY SHOULD EXCEED 90 DEGREES.
DEWPOINTS WELL INTO THE 60S WILL ADD TO THE DISCOMFORT. ALSO HAVE
LESS POP TUE THAN TODAY. CWFA SHOULD BE FIRMLY WITHIN THE UPPER
RIDGE BY THEN...WITH MODEL GUIDANCE CONSISTENT AND IN AGREEMENT
THAT LITTLE IN THE WAY OF FORCING WILL BE IN PLACE. FARTHER W IN
NY STATE CONVECTION SHOULD BE ONGOING...POSSIBLY STRONG...AND THIS
COULD SPILL OVER INTO WRN ZONES AS IT DECAYS.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
WEAKENING COLD FRONT WILL CONTINUE TO BRING SOME SCATTERED PRECIP
IN THE FORM OF SHOWERS AND SCATTERED THUNDERSTORMS ACROSS
NORTHERN NEW ENGLAND. BY THURSDAY...00Z MODEL SUITE IN GOOD
AGREEMENT WITH THE SURFACE FRONT BECOMING NEARLY STATIONARY OVER
OUR REGION. THIS INCREASES POPS AND WILL MOVE INTO THE LIKELY
CATEGORY THROUGH THURSDAY NIGHT DURING THIS PACKAGE UPDATE.
ON FRIDAY...A SYSTEM WILL MOVE UP THE MID ATLANTIC REGION. LATEST
EURO MODEL RUN DEEPENS THIS LOW RAPIDLY AS IT PASSES TO OUR EAST.
LITTLE IF ANY PRECIP EXPECTED WITH THE PASSAGE OF THIS
SYSTEM...HOWEVER SWELLS WILL BE ON THE INCREASE LATE IN THE
FORECAST PERIOD...LEADING TO ENHANCED RIP RISK.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
SHORT TERM...MAINLY VFR CONDITIONS TO PREVAIL THRU TUE. A WEAK
DISTURBANCE SHOULD LEAD TO WIDELY SCT SHRA/TSTMS THIS
AFTERNOON...WHICH COULD LEAD TO LOCAL MVFR OR LOWER CONDITIONS IN
THE MTNS. MODEL GUIDANCE IS FAIRLY AGGRESSIVE IN DEVELOPING
COASTAL FOG/STRATUS TONIGHT...BUT NOT CONFIDENT ENOUGH YET TO
INCLUDE IN TAFS.
LONG TERM...MAINLY VFR CONDITIONS EXPECTED. LOCAL MVFR OR LOWER
CONDITIONS POSSIBLE IN SHRA OR TSRA...ESPECIALLY THU INTO EARLY
FRI.
&&
.MARINE...
SHORT TERM...SW FLOW HAS ALREADY DEVELOPED OVER THE WATERS THIS
MORNING. COLD WATER TEMPS WILL SUPPORT A SHALLOW INVERSION WHICH
SHOULD LIMIT GUST POTENTIAL. EXPECT ANY GUSTS TO REMAIN BELOW 25
KTS. SEAS WILL GRADUALLY BUILD THRU TUE...AND A SCA FOR HAZARDOUS
SEAS MAY BE NECESSARY BY TUE.
LONG TERM...SLOWLY ADVANCING TROF WILL SET UP LONG DURATION
SOUTHWESTERLY FLOW OVER THE WATERS FOR MUCH OF THE WEEK. WIND FETCH
SHOULD EVENTUALLY ALLOW SEAS TO BUILD TO AT LEAST 5 FEET. LONG
PERIOD SWELLS MAY ARRIVE WITH AN OFFSHORE SYSTEM OVER THE WEEKEND.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...LEGRO
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1159 AM EDT MON JUN 30 2014
.SYNOPSIS...
WARMTH...HUMIDITY AND RAIN CHANCES WILL GIVE WAY TO DRY AND COMFORTABLE
WEATHER WITH PASSAGE OF A COLD FRONT ON THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
WARM AND HUMID CONDITIONS WL CONTINUE TDA ALTHOUGH UPR AIR
ANALYSIS AND MDLS INDICATE CHANGES AS DRIER AIR HAS BEEN ADVECTING
INTO THE MID LVLS OF UPR OH VALLEY AIRSPACE. PWS HAVE THUS
DIMINISHED...BUT POTENTIAL FOR WIND GUSTS HAS INCREASED VIA
EVAPORATIVE COOLING IN ANY CONVECTION THAT DOES DVLP. THAT CHC LKS
SLIM AS MID LVL TEMPS ARE VERY WARM OVR THE REGION...ABOUT 2
DEGREES ABOVE THE THERMAL TROF VALUES THAT DEFINED LAST EVES
SHRTWV PASSAGE.
NR TERM ADJUSTMENTS THUS FEATURE AN UPWARD TEMP ADJUSTMENT AND SLGT
CHC/ISOLD POPS FOR THE AFTN...WITH A SMALL INCRS TO CHC/SCT NMBRS
FOR THE EVE BASED ON INDICATIONS OF SOME IMPROVED FORCING VIA A
WEAK SHRTWV.
DIFFERENCE BTN INCOMING MDLS WL BE OF INTEREST GIVEN DISPARITIES
IN EARLY MRNG SOLNS AS RAP INDICATED MUCH DRIER SFC DEWPOINTS
MIXING OUT TDA THAN PROJECTED BY NAM. THAT FEW DEGREE DIFFERENCE
IS SIGNIFICANT IN TERMS OF CONVECTIVE CAPABILITY TDA...AND TRENDS
WL BE MONITORED CLOSELY.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY/...
RAIN CHCS WL BE ON THE INCRS TUESDAY WITH THE APPRCH OF A
CDFNT/UPR TROF. INCRSD SHEAR WITHIN THE ADVNG BAROCLINIC ZONE MAY
SPPRT SOME SVR STORMS...BUT TIMING OF THE IMPROVED WIND FIELD IN
CONJUNCTION WITH INSTABILITY PARAMETERS RMN IN DISPUTE. SPC HAS
PROJECTED A SLIGHT 15 PERCENT RISK WHICH WL BE REFINED DURING THE
NXT 24 HOURS. AT ANY RATE...LIKELY POPS FOR TUESDAY HAVE BEEN
MAINTAINED UNTIL THE ANTICIPATED FRONTAL PASSAGE DURING THE EVE.
THE FRONT IS CURRENTLY FORECAST TO BE STALLED NR THE RIDGES ON
WEDNESDAY AS LOW PRES MOVES ALNG THE BNDRY. THAT SCENARIO WOULD
MAINTAIN POPS FOR THOSE AREA INTO THURSDAY...WHILE WRN ZONES OF
THE CNTY WRNG AREA WL DRY AND COOL.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
MODELS ARE IN FAIRLY GOOD AGREEMENT FOR THE LONG TERM AS THE UPPER
LEVEL SLOWLY MOVES EASTWARD WHILE HIGH PRESSURE BUILDS AT THE SURFACE.
THIS SHOULD BRING DRY CONDITIONS THROUGH THE HOLIDAY WEEKEND WITH
TEMPS AOB THE SEASONAL AVERAGES.
&&
.AVIATION /16Z MONDAY THROUGH FRIDAY/...
MVFR STRATUS AND FOG WILL DISSIPATE DURING THE EARLY AFTERNOON...BUT
SLGT...TO CHC SHWRS AND TSTMS MAY SPAWN SOME RESTRICTIONS LTR TDA
AND THIS EVE. AT THIS POINT...WITH MINIMAL COVERAGE OF
PRECIPITATION EXPECTED...HAVE REMOVED VCTS AT ALL SITES.
.OUTLOOK.../TUESDAY THROUGH FRIDAY/...
OCCASIONAL RESTRICTIONS ARE POSSIBLE INTO THURSDAY AS A COLD FRONT
SLOWLY TRAVERSES THE REGION.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
944 AM EDT MON JUN 30 2014
.SYNOPSIS...
WARMTH...HUMIDITY AND RAIN CHANCES WILL GIVE WAY TO DRY AND COMFORTABLE
WEATHER WITH PASSAGE OF A COLD FRONT ON THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
WARM AND HUMID CONDITIONS WL CONTINUE TDA ALTHOUGH UPR AIR
ANALYSIS AND MDLS INDICATE CHANGES AS DRIER AIR HAS BEEN ADVECTING
INTO THE MID LVLS OF UPR OH VALLEY AIRSPACE. PWS HAVE THUS
DIMINISHED...BUT POTENTIAL FOR WIND GUSTS HAS INCREASED VIA
EVAPORATIVE COOLING IN ANY CONVECTION THAT DOES DVLP. THAT CHC LKS
SLIM AS MID LVL TEMPS ARE VERY WARM OVR THE REGION...ABOUT 2
DEGREES ABOVE THE THERMAL TROF VALUES THAT DEFINED LAST EVES
SHRTWV PASSAGE.
NR TERM ADJUSTMENTS THUS FEATURE AN UPWARD TEMP ADJUSTMENT AND SLGT
CHC/ISOLD POPS FOR THE AFTN...WITH A SMALL INCRS TO CHC/SCT NMBRS
FOR THE EVE BASED ON INDICATIONS OF SOME IMPROVED FORCING VIA A
WEAK SHRTWV.
DIFFERENCE BTN INCOMING MDLS WL BE OF INTEREST GIVEN DISPARITIES
IN EARLY MRNG SOLNS AS RAP INDICATED MUCH DRIER SFC DEWPOINTS
MIXING OUT TDA THAN PROJECTED BY NAM. THAT FEW DEGREE DIFFERENCE
IS SIGNIFICANT IN TERMS OF CONVECTIVE CAPABILITY TDA...AND TRENDS
WL BE MONITORED CLOSELY.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY/...
RAIN CHCS WL BE ON THE INCRS TUESDAY WITH THE APPRCH OF A
CDFNT/UPR TROF. INCRSD SHEAR WITHIN THE ADVNG BAROCLINIC ZONE MAY
SPPRT SOME SVR STORMS...BUT TIMING OF THE IMPROVED WIND FIELD IN
CONJUNCTION WITH INSTABILITY PARAMETERS RMN IN DISPUTE. SPC HAS
PROJECTED A SLIGHT 15 PERCENT RISK WHICH WL BE REFINED DURING THE
NXT 24 HOURS. AT ANY RATE...LIKELY POPS FOR TUESDAY HAVE BEEN
MAINTAINED UNTIL THE ANTICIPATED FRONTAL PASSAGE DURING THE EVE.
THE FRONT IS CURRENTLY FORECAST TO BE STALLED NR THE RIDGES ON
WEDNESDAY AS LOW PRES MOVES ALNG THE BNDRY. THAT SCENARIO WOULD
MAINTAIN POPS FOR THOSE AREA INTO THURSDAY...WHILE WRN ZONES OF
THE CNTY WRNG AREA WL DRY AND COOL.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
MODELS ARE IN FAIRLY GOOD AGREEMENT FOR THE LONG TERM AS THE UPPER
LEVEL SLOWLY MOVES EASTWARD WHILE HIGH PRESSURE BUILDS AT THE SURFACE.
THIS SHOULD BRING DRY CONDITIONS THROUGH THE HOLIDAY WEEKEND WITH
TEMPS AOB THE SEASONAL AVERAGES.
&&
.AVIATION /13Z MONDAY THROUGH FRIDAY/...
MVFR AND IFR STRATUS AND FOG WILL GRADUALLY DISSIPATE THROUGH
MIDDAY...BUT SLGT...TO CHC SHWRS AND TSTMS MAY SPAWN SOME
RESTRICTIONS LTR TDA AND THIS EVE. FOR NOW...WILL CARRY VCTS AT
ALL SITES THIS AFTERNOON.
.OUTLOOK.../TUESDAY THROUGH FRIDAY/...
OCCASIONAL RESTRICTIONS ARE POSSIBLE INTO THURSDAY AS A COLD FRONT
SLOWLY TRAVERSES THE REGION.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
15
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1115 AM EDT MON JUN 30 2014
.UPDATE...
STILL TRACKING THE THREAT FOR SEVERE WEATHER THROUGH THIS
EVENING AND TONIGHT. 12Z OBS AND MODEL OUTPUT CONTINUE THE
PREVIOUS TRAIN OF THOUGHT WITH HIGH INSTABILITY THIS AFTERNOON AND
EVENING THAT LACK A FORCING MECHANISM. AFTER MIDNIGHT...MCS RACING
ACROSS LAKE MICHIGAN WILL TAP INTO SLIGHTLY LESS UNSTABLE AIRMASS.
BULK SHEER INCREASES LATE NIGHT AS WELL WITH 0-6KM VALUES NEAR
60KT IN THE SAGINAW VALLEY. 12Z NAM OUTPUT SPORTED A 5500 J/KG POWDER
KEG AT 21Z IN KLAN...BUT BASED OFF OF A BRAVADO 86/76 SURFACE
PARCEL. MOST LIKELY SCENARIO WILL BE WIDELY SCATTERED SHOWERS IN
THE 20-00Z TIME FRAME WITH ORGANIZED BOW ECHO/DERECHO MOVING
THROUGH THE AREA 04-10Z. SUPPORT FOR DERECHO THREAT INCLUDES RIGHT
REAR 115KT JET SUPPORT...LLJ OF 40-50KT AT H85 AND 55-65KT AT H5.
REMNANT JUICY CAPE OF 2500 J/KG AND DCAPE NEAR 2000 J/KG WILL BE
SUPPORTIVE OF ACCELERATING COLD POOLS. HRRR ...ARW...AND NMM HI-
RES MODELS ALL POINT TO A SIMILAR SOLUTION TONIGHT WITH DIFFERING
STRENGTH AND LOCATION OF MULTICELL LINE/CLUSTERS MOVING THROUGH
THE CWA.
&&
.AVIATION...ISSUED 847 AM EDT MON JUN 30 2014
//DISCUSSION...
DISSIPATING MCS WILL PROVIDE BKN-OVC CIRRUS DECK AND A PERIOD OF
MVFR CIGS EARLY IN THE FORECAST. THE TIMING/LOCATION OF THIS SYSTEMS
DEMISE AND OVERALL LACK OF UPPER LEVEL SUPPORT WILL LIMIT CONVECTIVE
COVERAGE DURING THE DAY...BUT EXPECT RE-NEWED STORM CHANCES BY THIS
EVENING INTO THE OVERNIGHT AS VIGOROUS SHORTWAVE BRINGS ANOTHER MCS
INTO AREA. THIS SYSTEM...WHILE IT WILL MOST LIKELY WEAKEN SOMEWHAT
AS WELL...SHOULD HAVE ENOUGH UPPER LEVEL SUPPORT TO AFFECT THE
TERMINALS LATE IN THE FORECAST PERIOD.
//DTW THRESHOLD THREATS...
* LOW CONFIDENCE IN THUNDERSTORM POTENTIAL AND TIMING LATE TODAY
WITH HIGHER CONFIDENCE TONIGHT.
* LOW CONFIDENCE IN CEILINGS AOB 5000 FEET TONIGHT.
&&
.PREV DISCUSSION...ISSUED 708 AM EDT MON JUN 30 2014
UPDATE...
UPDATED TO REMOVE EARLY MORNING RAIN CHANCES AS OVERNIGHT MCS TO
THE WEST HAS ALL BUT DISSIPATED NORTH OF THE MICHIGAN AND INDIANA
STATE LINE.
WITH MODERATELY UNSTABLE CONDITIONS DEVELOPING TODAY AS DEW POINTS
HOLD CLOSE TO 70 AND TEMPERATURES APPROACH 90...EXPECT ISOLATED TO
SCATTERED STORMS LATE THIS AFTERNOON. HOWEVER...IT STILL APPEARS
THE MOST IMPRESSIVE ACTIVITY WILL TRACK IN FROM THE WEST THIS
EVENING INTO THE OVERNIGHT HOURS AS A STRONG SHORTWAVE PIVOTS INTO
THE GREAT LAKES. TIMING OF THE CONVECTIVE SYSTEM ASSOCIATED WITH
THIS FEATURE REMAINS IN QUESTION. THE LATER IT ARRIVES...THE LESS
ORGANIZED/SEVERE THE CONVECTION WILL BE.
&&
.PREV DISCUSSION...ISSUED 316 AM EDT MON JUN 30 2014
SHORT TERM...TODAY AND TONIGHT
WHILE NORTHERN EXTENT OF THE MCS EXTENDING FROM LAKE MICHIGAN
SOUTHWEST INTO NORTHERN ILLINOIS HAS BECOME LESS ORGANIZED OVER THE
PAST 3 OR 4 HOURS...AND MODELS SUGGEST THIS TREND WILL CONTINUE
INTO THE MORNING AS THE ACTIVITY OUTRUNS ITS SUPPORTING LOW LEVEL
JET...IT APPEARS SOME OF THIS CONVECTION WILL MOVE INTO THE CWA
EARLY THIS MORNING BEFORE FADING DURING THE CLIMATOLOGICAL MINIMUM
FOR CONVECTION AFTER SUNRISE. WILL REDRAW POPS TO ADJUST FOR THESE
TRENDS.
OTHERWISE...WIDELY SCATTERED/SCATTERED CONVECTION WILL MOST LIKELY
RE-DEVELOP DURING THE AFTERNOON ALONG OUTFLOW FROM THIS SYSTEM AND
ALSO IMMEDIATELY ALONG LAKE/LAND INTERFACE. THIS ACTIVITY SHOULD
REMAIN RATHER DISORGANIZED WITH SPARSE COVERAGE GIVEN LACK OF UPPER
LEVEL SUPPORT AND LOW LEVEL FORCING.
CONDITIONS WILL CHANGE THIS EVENING INTO TONIGHT AS SIGNIFICANT
UPPER LEVEL SUPPORT ENCROACHES ON THE AREA AS VIGOROUS SHORTWAVE
PIVOTS THROUGH THE UPPER MIDWEST INTO THE GREAT LAKES AROUND UPPER
LOW PRESSURE STILL CENTERED NEAR LAKE WINNIPEG. THUNDERSTORMS WILL
BE ESPECIALLY IMPRESSIVE TO OUR WEST AS THE AFFECTS OF THIS WAVE
COINCIDE WITH PEAK DAYTIME HEATING DURING THE AFTERNOON/EARLY
EVENING. THAT SAID...EXPECT THE LARGE CONVECTIVE SYSTEM THAT DOES
EVOLVE OUT OF INITIAL SEVERE CONVECTION TO RACE INTO THE AREA BY
EVENING...PROBABLY FASTER THAN MODELS SUGGEST AS EXPANDING SYSTEM
DEVELOPS A SIGNIFICANT COLD POOL WITH TIME. INSTABILITY WILL STILL
BE RATHER IMPRESSIVE DURING THE MID/LATE EVENING GIVEN THE INFLUX OF
WARM/MOIST AIR INTO THE AREA. WILL MAINTAIN GENERALLY CHANCE POPS
DURING THE AFTERNOON/EARLY EVENING WITH LIKELY FROM MID/LATE EVENING
INTO THE OVERNIGHT HOURS.
WITH SBCAPES ON THE ORDER OF 3000 J/KG BY LATE IN THE DAY AND 0-6KM
BULK SHEAR INCREASING FROM 25-35 KTS TO AROUND 45 KTS DURING THE
COURSE OF THE EVENING...EXPECT SEVERE WEATHER TO BE A DISTINCT
POSSIBILITY. THE EXTENT/MAGNITUDE...AS IS OFTEN THE CASE...WILL BE
DICTATED BY HOW CURRENT CONVECTION INFLUENCES ATMOSPHERIC CONDITIONS
AND HENCE DEVELOPMENT/EVOLUTION OF MAIN MCS IN QUESTION LATER TODAY.
WITH ANY LUCK...THE ARRIVAL INTO THE AREA SEVERAL HOURS AFTER PEAK
HEATING WILL ALLOW FOR SOME MODEST WEAKENING OF OVERALL CONVECTIVE
SYSTEM OVER SOUTHEAST LOWER MICHIGAN.
LONG TERM...
LONGWAVE PATTERN OVER NORTH AMERICA WILL BUCKLE EARLY IN THE LONG
TERM PERIOD IN RESPONSE TO DEEPENING LOW APPROACHING THE PACIFIC
NORTHWEST. AS THIS OCCURS, THE STRONG CLOSED LOW OVER MANITOBA WILL
TRANSITION TO AN OPEN WAVE AND BE SWEPT NORTHEAST AS LONGWAVE
TROUGHING AMPLIFIES OVER THE GREAT LAKES, BRINGING MARKEDLY COOLER
TEMPERATURES BY LATE WEEK. OCCASIONAL LOW AMPLITUDE WAVES EMBEDDED
IN THE FLOW WILL BRING EPISODIC CLOUD COVER OR SHOWER CHANCES BEFORE
HIGH PRESSURE BUILDS IN FROM THURSDAY ONWARD.
COLD FRONT WHICH WILL PROVIDE THE FOCUS FOR THIS AFTERNOON`S SEVERE
CONVECTION OVER THE CENTRAL UNITED STATES IS PROGGED TO BE BISECTING
THE CWA BY 12Z TUESDAY MORNING. THE PRESENCE OF A WELL-DEFINED FRONT
AND INCREASING DIURNAL HEATING ALONE WARRANTS LOW CHANCE POPS BEFORE
THE FRONT EXITS TO THE EAST BY AROUND 18Z. IN REALITY, THE REGIONAL
ENVIRONMENT WILL HAVE UNDERGONE POTENTIALLY SIGNIFICANT MODIFICATION
COURTESY OF TODAY/TONIGHT`S WIDESPREAD CONVECTIVE EPISODE. COULD SEE
ANYTHING RANGING FROM CONVECTIVE REMNANTS BEING SWEPT INTO THE CWA
WITHIN DEVELOPING SOUTHWEST FLOW TO DRY CONDITIONS OWING TO
SUBSIDENCE IN THE WAKE OF CONVECTION. MOST PRUDENT PLAY AT THIS TIME
APPEARS TO BE FOR 30-40 TYPE POPS ALONG/AHEAD OF THE FRONTAL ZONE.
DRIER AND MORE STABLE AIR WILL FILTER IN FOR THE REMAINDER OF THE
DAY, ENDING PRECIP CHANCES BY AFTERNOON AND CAPPING HIGHS IN THE
LOW/MID 80S.
FAIRLY POTENT SHORTWAVE IS THEN FORECAST TO SWING THROUGH THE GREAT
LAKES DURING THE DAYTIME HOURS ON WEDNESDAY. INSTABILITY WILL BE
QUITE LIMITED, PERHAPS 500 J/KG, AS DEWPOINTS FALL TO AROUND 60F.
HOWEVER, SUPERPOSITION OF DYNAMIC FORCING WITH ONGOING LIGHT COLD
ADVECTION IS EXPECTED TO PROVIDE A FAVORABLE ENVIRONMENT FOR
AGGRESSIVE EXPANSION OF DIURNAL CLOUD COVER AS WELL AS SCATTERED
SHOWERS IN ADVANCE OF THE WAVE.
SECONDARY WAVE OF COLD ADVECTION WILL GET UNDERWAY WITH THE PASSAGE
OF WEDNESDAY`S WAVE. BY THURSDAY MORNING, H85 TEMPERATURES ARE
PROGGED TO BE SOLIDLY IN THE SINGLE DIGITS. OVERNIGHT LOW
TEMPERATURES WILL BE DEPENDENT ON CLOUD COVER, OF WHICH THERE SHOULD
BE PLENTY GIVEN ONGOING BOUNDARY LAYER MIXING AND CONTINUED CYCLONIC
FLOW ALOFT. THUS, SIDED WITH THE CONSENSUS FOR WEDNESDAY NIGHT WHICH
SHOWS MOST SPOTS DIPPING DOWN INTO 50S BY THURSDAY MORNING...PERHAPS
UPPER 40S IN THE SAGINAW VALLEY.
TEMPERATURE RECOVERY WILL BE LIMITED ON THURSDAY OWING THE POSITION
OF THE THERMAL TROUGH DIRECTLY OVERHEAD AND THE POTENTIAL FOR
ANOTHER ROUND OF HEALTHY BOUNDARY LAYER CLOUD DEVELOPMENT. EXPECT
HIGHS TO REACH THE LOW 70S...UPPER 60S IN THE THUMB. HIGH PRESSURE
WILL THEN SETTLE IN FOR THE REMAINDER OF THE LONG TERM PERIOD AND
GRADUAL AIRMASS RECOVERY WILL LEAD TO SLOWLY RISING TEMPS THROUGH
THE WEEKEND.
MARINE...
LIGHT TO MODERATE SOUTHWEST FLOW WILL PERSIST THROUGH MIDWEEK UNTIL
A COLD FRONT TURNS WINDS MORE TO THE NORTHWEST AND ALLOWS COOLER AIR
TO OVERSPREAD AREA WATERS. WITH NO NOTEWORTHY WIND EVENTS ON THE
HORIZON...THE PRIMARY CONCERN WILL BE THUNDERSTORM ACTIVITY WHICH
WILL PLAGUE THE AREA THROUGH LATE TONIGHT. ALTHOUGH COVERAGE OF
STORMS OVER THE WATERS IS UNCERTAIN...A FEW SEVERE STORMS IS NOT OUT
OF THE QUESTION. HIGH PRESSURE WILL BUILD ACROSS THE GREAT LAKES BY
THE END OF THE WEEK.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.
&&
$$
UPDATE.......MM
AVIATION.....DG
SHORT TERM...DG
LONG TERM....JVC
MARINE.......JVC
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
732 AM EDT MON JUN 30 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 432 AM EDT MON JUN 30 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW WSW FLOW OVER THE
UPR LKS ARND UNSEASONABLY DEEP CLOSED LO CENTERED NEAR LK WINNIPEG.
A SHRTWV THAT ROTATED ACRS NRN LK SUP EARLY THIS MRNG GENERATED SOME
SHOWERS/TS OVER THE CWA EARLIER...BUT VIGOROUS H85-7 DRY ADVCTN
DOWNSTREAM OF VERY DRY 00Z MPX RAOB /WHERE THE 00Z PWAT WAS NEAR
0.75 INCH OR ABOUT 85 PCT OF NORMAL/ AND DNVA/DEEP LYR QVECTOR DVGC
AS WELL AS NOCTURNAL COOLING HAVE ENDED THIS PCPN. HOWEVER...STEEP
LAPSE RATES SHOWN ON THE 00Z MPX RAOB HAVE ALLOWED SOME ISOLD
SHOWERS/TS TO POP UP FM TIME TO TIME OVER NCENTRAL WI AND CENTRAL
UPR MI DESPITE THE LARGER SCALE DRYING TRENDS/NOCTURNAL COOLING.
ANOTHER LARGER CLUSTER OF SHOWERS/TS IS PRESENT OVER SE WI...WHERE
THE SHRTWV IN SCENTRAL MN IS INTERACTING WITH AREA OF HIER H85-7
DEWPTS ON SE FLANK OF DRY WEDGE PUSHING INTO UPR MI. FARTHER
UPSTREAM...THERE ARE SEVERAL SHRTWVS MOVING EWD THRU THE NRN PLAINS
IN THE WLY FLOW ON THE SRN FLANK OF CLOSED LO.
MAIN FCST CONCERNS DURING THIS TIME ARE SHOWER/TS CHANCES...
ESPECIALLY LATE TODAY/TNGT WHEN A STRONGER SHRTWV ROTATING ARND THE
CLOSED LO IS FCST TO MOVE THRU THE UPR MIDWEST.
EARLY THIS MRNG/TODAY...DRY AIR SWEEPING ENEWD WITH H85-5 MEAN LYR
RH DOWN TO 30-40 PCT SHOULD ENSURE DRY WX FOR MOST OF THE CWA THIS
MRNG EVEN THOUGH SHRTWV NOW IN MN AND ASSOCIATED DPVA/SOME DEEP LYR
QVECTOR CNVGC ASSOCIATED WITH SHRTWV NOW OVER SCENTRAL MN WL SWING
ACRS THE AREA. HOWEVER...DID ALLOW FOR SOME LINGERING ISOLD
SHOWERS/TS OVER THE SE HALF OF THE CWA THRU ABOUT 15Z TO ACCOUNT FOR
THIS SHRTWV/FORCING/STEEP H85-5 LAPSE RATES UP TO 8-8.5C/KM. THESE
SHOWERS SHOULD END FOLLOWING THE EXIT OF THE SHRTWV/ARRIVAL OF
DNVA/LARGE SCALE QVECTOR DVGC. PCPN CHCS WL INCRS LATER IN THE AFTN
WITH APRCH OF STRONGER SHRTWV ROTATING ARND THE SSE FLANK OF CLOSED
LO SLOWLY DRIFTING INTO FAR NW ONTARIO. AS THE H85 WINDS BACK A BIT
WITH THE APRCH OF THIS STRONGER DISTURBANCE...MODELS INDICATE HIER
H85-7 DEWPTS/WL SURGE NEWD INTO MAINLY THE SE HALF OF THE CWA. IN
CONCERT WITH ACCOMPANYING DPVA/DEEP LYR QVECTOR CNVGC ASSOCIATED
WITH THE SHRTWV AND H4-2 DVGC IN RRQ OF 100KT H3 JET MAX MOVING THRU
NW LK SUP...WL CONT TO SHOW INCRSG POPS OVER MAINLY THE SCENTRAL
LATE IN THE DAY. CONSIDERING THE RATHER IMPRESSIVE DYNAMICS/MSTR
RETURN THAT IS FCST TO LIFT PWAT CLOSE TO 2 INCHES OVER THE SCENTRAL
BY 00Z /175 PCT OF NORMAL/...PREFER THE HIER POPS A BIT FARTHER TO
THE W/HIER QPF SHOWN BY THE 00Z NAM/REGIONAL CNDN MODEL. AS FOR
TEMPS...EXPECT THE HIEST TEMPS OVER THE INTERIOR W HALF WHERE THERE
WL BE MORE SUNSHINE THRU MUCH OF THE DAY UNTIL CLDS BEGIN TO INCRS
THIS AFTN. DEEP MIXING TO H75 WL SUPPORT HI TEMPS APRCHG 85 AND
ALLOW FOR GUSTY WINDS TO MIX TO THE SFC.
TNGT...VIGOROUS DYNAMICS/MSTR RETURN ARE FCST TO IMPACT MAINLY THE
SE 2/3 OF THE CWA IN THE 00Z-06Z PERIOD AND JUSTIFY SOME CATEGORICAL
POPS OVER THE SE CWA IN THE EVNG BEFORE DNVA/DEEP LYR QVECTOR
DVGC/MID LVL DRYING RETURNS IN THE WAKE OF SHRTWV PASSAGE.
CONSIDERING THE UNSEASONABLY STRONG UPR DYNAMICS...THERE IS SOME
CONCERN AS TO WHETHER ANY OF THE TS COULD BE STRONG TO SEVERE. THE
LATEST SPC CONVECTIVE OUTLOOK SHOWS UPR MI JUST N OF THE THE SLGT
RISK AREA. THE BEST CHC FOR SOME SVR TS WOULD BE WHEN THE DYNAMICS
ARRIVE LATE THIS AFTN WHEN LLVL LAPSE RATES ARE STILL STEEP/DCAPE
WOULD BE HIER FOLLOWING THE DAYTIME HEATING AND WHEN THE LLVL
ENVIRONMENTAL WINDS ARE A UNIDIRECTIONAL SW AND AS HI AS 50 KTS AT
H7. GUSTY WINDS WOULD BE THE MAIN THREAT. DURING THIS EVNG...HEAVY
RA LOOKS TO BE THE MAIN CONCERN WITH RATHER HI FRZG LVL NEAR 13K FT/
MARGINAL MID LVL LAPSE RATES DESPITE SOME FAIRLY STRONG WINDS ALF.
ARRVIAL OF SOME COOLER AIR/MID LVL DRYING WL ALLOW TEMPS OVER THE W
TO FALL INTO THE 50S TNGT. SOME LOCALLY DENSE FOG COULD OCCUR OVER
THE E LATE WITH SOME MID LVL DRYING FOLLOWING DEPARTING SHRTWV OVER
THE RA MOISTENED LLVLS WITH SW FLOW OFF LK MI.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 328 AM EDT MON JUN 30 2014
A LARGE UPPER TROUGH WILL STILL BE IN PLACE OVER ONTARIO AND THE
NORTH CENTRAL CONUS ON TUESDAY MORNING. A SHORTWAVE ROTATING AROUND
THIS UPPER TROUGH WILL SHIFT THROUGH THE UPPER GREAT LAKES REGION
TONIGHT AND BE PULLING NORTHEAST OUT OF THE AREA. EXPECT ANY
CONVECTION ASSOCIATED WITH THIS SHORTWAVE AND LOW CENTER TO QUICKLY
BE MOVING NORTHEAST THROUGH ONTARIO ON TUESDAY MORNING. A COLD FRONT
STRETCHING SOUTHEAST FROM THE LOW IN ONTARIO WILL TRACK ACROSS THE
UPPER GREAT LAKES REGION TUESDAY AFTERNOON AND NIGHT...LEADING TO
ANOTHER OPPORTUNITY FOR SHOWERS AND MAYBE A FEW THUNDERSTORMS.
EXPECT THE BULK OF THE SHOWER COVERAGE TO DEVELOP OVER THE LAND
AREAS AROUND NOON ON TUESDAY AND SPREAD IN COVERAGE THROUGH THE
AFTERNOON HOURS. THINK THE BEST COVERAGE WILL BE OVER THE
EAST/SOUTHEAST HALF OF UPPER MICHIGAN...ESPECIALLY
ALGER/SCHOOLCRAFT/LUCE COUNTIES WHERE THERE WILL BE SOME HELP FROM
CONVERGENCE OFF LAKE SUPERIOR. WILL CONTINUE TO SHOW HIGH CHANCE OR
LOW END LIKELY VALUES IN THOSE AREAS. FARTHER TO THE WEST...COVERAGE
IS A LITTLE MORE UNCERTAIN DUE TO INDICATIONS OF A WEAK SURFACE
TROUGH SHIFTING THROUGH DURING THE DAY. THIS WILL SHIFT WINDS A
LITTLE MORE WESTERLY (OR EVEN NORTHWESTERLY) AND BRING IN MORE
STABLE AIR FROM LAKE SUPERIOR. THINK THAT WILL KEEP MUCH OF THE
KEWEENAW PENINSULA DRY AND WILL HOLD ONTO SLIGHT OR LOW CHANCES FOR
THE REST OF THE WESTERN HALF OF UPPER MICHIGAN. MID LEVEL LAPSE
RATES ARE ONLY AROUND 5-6 C/KM...HELPING TO LIMIT THUNDER POTENTIAL
AND KEEPING ML CAPES GENERALLY BELOW 200 J/KG. THUS...WILL CONTINUE
TO KEEP THUNDER CHANCES CAPPED AT SLIGHT CHANCES (ALTHOUGH WITH THE
LATEST TRENDS THAT MAY BE GENEROUS). IN ADDITION...IT WILL BE BREEZY
OVER THE KEWEENAW ON TUESDAY. A TIGHT PRESSURE GRADIENT AND STRONGER
WINDS ALOFT (950-925MB WINDS OF 30-35KTS) WILL LEAD TO GUSTS
AROUND 30KTS OVER THE HIGHER TERRAIN LOCATIONS...ALTHOUGH THE MARINE
LAYER MAY TRY TO HOLD SOME OF THE WINDS AT BAY NEAR THE SHORELINE.
AS THE COLD FRONT SHIFTS THROUGH LATE TUESDAY AFTERNOON AND
EVENING...A PERIOD OF ABUNDANT LOW LEVEL MOISTURE AND NORTHWEST FLOW
WILL DEVELOP OVER THE AREA AND LINGER INTO THE OVERNIGHT HOURS. WITH
THE FAVORABLE UPSLOPE FLOW...THINK THE BEST OPPORTUNITY FOR SHOWERS
WILL BE IN THE NORTHWEST WIND FAVORED LOCATIONS IN THE NW HALF OF
UPPER MICHIGAN. DON/T EXPECT THE AMOUNTS TO BE ANYTHING TOO
IMPRESSIVE...A FEW HUNDREDTHS...BUT WILL SHOW CHANCE POPS IN THE
HIGHER TERRAIN FROM GOGEBIC COUNTY THROUGH THE KEWEENAW AND ALSO
HIGHER TERRAIN OF BARAGA AND WESTERN MARQUETTE COUNTY. EXPECT
THESE SHOWERS TO CUT OUT FAIRLY QUICKLY AROUND DAYBREAK...AS MUCH
DRIER AIR SURGES SOUTHEAST INTO THE AREA. THIS WILL LEAD TO
DECREASING CLOUDS FROM NW TO SE ON WEDNESDAY MORNING AND EXPECT THE
AFTERNOON TO BE SUNNY FOR ALL BUT THE SOUTH CENTRAL (WHERE THERE
COULD BE SOME LINGERING DIURNAL CU). WITH THE NORTHWEST WINDS ON
WEDNESDAY...THERE MAY BE AN ELEVATED SWIM RISK FOR ALGER COUNTY
BEACHES. BUT WITH TEMPERATURES STRUGGLING TO GET OUT OF THE
50S...THE AMOUNT OF SWIMMERS WILL BE LIMITED IN THE LOW 40 DEGREE
WATER TEMPERATURES. ELSEWHERE...HIGHS WILL BE WELL BELOW NORMAL AND
IN THE 60S.
HIGH PRESSURE DEVELOPING OVER THE NORTHERN/CENTRAL PLAINS ON
WEDNESDAY WILL SHIFT A RIDGE EAST OVER THE UPPER GREAT LAKES REGION
WEDNESDAY AFTERNOON AND NIGHT. THIS RIDGE WILL STAY IN PLACE
THROUGH THE REST OF THE WORK WEEK...AS THE HIGH SHIFTS THROUGH THE
GREAT LAKES REGION AND THEN INTO THE MID ATLANTIC STATES ON
SATURDAY. THERE SHOULD BE COOLER AND GENERALLY CLEAR CONDITIONS
DURING THIS PERIOD...ALTHOUGH A WEAK SHORTWAVE MAY LEAD TO SOME
CLOUDS ON THURSDAY. EXPECT THE LOWEST LOW TEMPERATURES ON WEDNESDAY
NIGHT...WITH GOOD RADIATIONAL COOLING UNDER CLEAR SKIES...LIGHT
WINDS...AND PWATS AROUND 40 PERCENT OF NORMAL. LIKED THE TREND
SHOWN BY THE PREVIOUS SHIFT (TOWARDS THE BETTER PERFORMING MEX
GUIDANCE ON RADIATIONAL COOLING NIGHTS) AND WILL CONTINUE THAT IDEA.
THAT GIVES LOWS FOR SOME OF THE COLD SPOTS OUT WEST IN THE LOWER 40S
AND UPPER 30S. SHOULD SEE GRADUALLY WARMING HIGHS/LOWS FOR THE REST
OF THE WORK WEEK AND THE 4TH OF JULY STILL LOOKS TO BE A GREAT DAY
FOR OUTDOOR ACTIVITIES. HIGHS WILL BE CLOSE TO NORMAL (70S) UNDER
MOSTLY SUNNY SKIES AND GENERALLY LIGHT WINDS.
HEADING INTO THE WEEKEND...MODELS ARE CONTINUING TO STRUGGLE WITH A
POTENTIAL SHORTWAVE MOVING THROUGH THE NEARLY ZONAL FLOW. THAT IS
TO BE EXPECTED AND LEADS TO LOW CONFIDENCE FOR FRIDAY NIGHT INTO
SATURDAY. WILL SHOW GENERALLY SLIGHT CHANCES INCREASING OVER THE
WESTERN HALF OF THE CWA DURING THIS PERIOD...WITH THE DRY AIR FROM
THE HIGH KEEPING THE EAST DRY. THE INCREASING SOUTHERLY FLOW OVER
THE AREA THIS WEEKEND WITH THE HIGH SHIFTING TO THE SOUTHEAST WILL
LEAD TO AN INCREASE IN TEMPS TO MORE NORMAL OR SLIGHTLY ABOVE
NORMAL VALUES AND ALSO PRODUCE MORE HUMID CONDITIONS. SUNDAY VARIES
TOO...SO WILL GO WITH A CONSENSUS OF THE MODELS AND LEADS TO POPS
SIMILAR TO CLIMO.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 731 AM EDT MON JUN 30 2014
AN AREA OF LOWER CLDS OVER NCENTRAL WI WL DRAWN INTO CENTRAL UPR MI
EARLY THIS MRNG AND MAY IMPACT SAW WITH SOME MVFR CIGS AT TIMES
EARLY THIS MRNG BEFORE DAYTIME HEATING MIXES OUT THE LLVL MSTR AND
ENDS LLWS AT CMX/SAW. OTRW...VFR CONDITIONS WL DOMINATE TODAY. AS A
STRONG DISTURBANCE MOVING INTO THE NRN PLAINS APRCHS THE UPR LKS
LATER TODAY...MORE MOIST AIR WL BE DRAWN NEWD OVER THE SE HALF OF
UPR MI. THE COMBINATION OF THE DYNAMIC FORCING AHEAD OF THIS
DISTURBANCE AND THE MSTR RETURN WL BRING SOME SHRA AND PERHAPS A TS
TO SAW ALONG WITH MVFR CONDITIONS FOR A TIME THIS EVNG. AFTER DRYING
ALOFT FOLLOWS THE DEPARTING DISTURBANCE...SOME FOG/LO CLDS AND IFR
CONDITIONS MAY DVLP AT SAW OVER THE RA MOISTENED LLVLS IN THE
PRESENCE OF NOCTURNAL COOLING. MORE LLVL MSTR WRAPPING INTO THE WRN
U.P. IN A CYC...UPSLOPE WLY FLOW IS LIKELY TO BRING SOME MVFR CIGS
TO IWD AND CMX LATE IN THE FCST PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 328 AM EDT MON JUN 30 2014
A STRONG LOW PRESSURE SYSTEM NEAR LAKE WINNIPEG WILL GRADUALLY
SHIFT EAST ACROSS ONTARIO TODAY AND TONIGHT...BEFORE MERGING WITH A
SECONDARY LOW NEAR JAMES BAY ON TUESDAY. EXPECT SOUTH TO
SOUTHWESTERLY WINDS DURING THIS PERIOD...BUT THE MARINE LAYER
SHOULD KEEP WINDS BELOW 25KTS. WARM AND HUMID AIR MOVING OVER LAKE
SUPERIOR WILL CONTINUE TO BRING THE OPPORTUNITY FOR FOG...WITH THE
BEST CHANCE OF LOCALLY DENSE FOG OVER THE NORTHERN HALF OF LAKE
SUPERIOR. A COLD FRONT WILL MOVE SOUTHEAST ACROSS LAKE SUPERIOR ON
TUESDAY NIGHT AND SHIFT WINDS TO THE WEST-NORTHWEST. THIS WILL ALSO
BRING AN END TO THE FOG POTENTIAL AS COOLER AND DRIER AIR MOVES
INTO THE AREA. A HIGH PRESSURE RIDGE WILL DEVELOP OVER LAKE
SUPERIOR ON WEDNESDAY AFTERNOON AND REMAIN THROUGH SATURDAY AS THE
PARENT HIGH SHIFTS EAST FROM THE PLAINS STATES TO THE MID ATLANTIC
STATES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...KC
MARINE...SRF
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1135 AM EDT MON JUN 30 2014
.SYNOPSIS...
HIGH PRESSURE OFF THE EAST COAST WILL CONTINUE TO PUMP A SOUTHERLY
FLOW OF VERY WARM AND HUMID AIR FOR NEW YORK AND PENNSYLVANIA
THROUGH TUESDAY. WITH THE WARM AND HUMID AIR MASS IN PLACE
EXPECT MORE SCATTERED SHOWERS AND THUNDERSTORMS THIS AFTERNOON
AND EVENING. A COLD FRONT WILL BRING MORE WIDESPREAD SHOWERS AND
THUNDERSTORMS TUESDAY. SOME OF THIS STORMS MAY PRODUCE STRONG
WINDS AND VERY HEAVY RAIN LATER TUESDAY, ESPECIALLY OVER CENTRAL
NY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
RADAR SHOWS SHRA AND ISLD TSRA PERSISTING IN THE SRN CATSKILLS AT
THIS TIME IN ASSCTN WITH A WEAKENING SHRT WAVE THAT HAS TRACKED E
OVERNIGHT AND WAS NOW ALMOST UNDER THE UPPER LEVEL RDG AXIS. THIS
FEATURE WILL CONT E AND ALL PRECIP SHUD EXIT THE SRN CATSKILLS BY
AFTERNOON. HAVE LIKELY POPS FOR THE NEXT HOUR OR SO TO COVER DOWN
THERE. REST OF CENTRAL NY/NE PA WAS DRY AT THIS TIME.
MAIN QUESTION IS WHERE AND HOW MUCH CONVECTION DEVELOPS AGAIN THIS
AFTERNOON AND INTO THE EVENING ASSCTD WITH STRG LATE JUNE
INSOLATION. MODELS BUILD UP CAPES BETWEEN 1000 AND 2000 J/KG OR
EVEN MORE ESPECIALLY ACROSS NC NY TO WRN NY WITH MUCH LESSER CAPE
VALUES FARTHER SOUTH TWD NE PA AND THE CATSKILLS. THIS IS ASSCTD
WITH STRGER SWRLY LOW-LEVEL FLOW THAT CONTINUES TO PREFERENTIAL
ADVECT HIGHER BNDRY LAYER DEWPOINTS UP THRU WRN NY WITH HIGHER
MEAN BL DEWPOINTS THAN FARTHER SOUTHEAST INTO NE PA AND THE
CATSKILLS. CAPES THIS AFTERNOON CONSISTENTLY ARE HIGHER IN OUR NW
COUNTIES...FINGER LAKES TO SYR AREA ON ALL MODELS. THE LATEST NAM
HAS CAPES APPROACHING 3000 J/KG AND IN MANY OF THESE AREAS WELL
VER 2000 J/KG!! THE GFS AND EURO ARE TAMER WITH 1000 TO 2000 J/KG
WHICH STILL IS HEALTHY. THE NAM HAS SFC DWPTS ARND 71-72F IN NC NY WHICH
IS NOT OUT OF THE QUESTION.
SO WE KNOW WE ARE GOING TO HAVE MORE THAN SUFFICIENT CAPE IN
CENTRAL NY FOR TSRA. MAIN QUESTION IS WHERE IS THE FORCING GOING
TO COME FROM? THE WIND SHEAR IS ALSO FAIRLY WEAK AS WELL SO ANY
STORMS THAT FORM WON`T BE TOO ORGANIZED. WATER VAPOR IMAGERY
CONTINUES TO SHOW A BARRAGE OF SMALLER SHORT WAVES OR MORE LIKELY
CONVECTIVELY INDUCED WAVES FROM UPSTREAM CONVECTION HEADING E-NE
TWD NY AND PA THRU TUESDAY AM. THE NEXT WAVE THAT WAS APPROACHING
OUR AREA WAS OVER THE ERN LAKES ASSCTD WITH DARKENING ON THE WATER
VAPOR IMAGERY. LATEST RAP ALSO SHOWS THIS WAVE ACVTY AS TROP
PRESSURES ARE A LOCAL MAXIMUM IN PRESSURE BASED ON THE 1.5 PVU
UNIT SFC. MODEL SOUNDINGS SHOW SOME OMEGA THIS AFTERNOON AS WELL
BEFORE THE MODELS CONVECT OUT SUGGESTING SOME SORT OF LARGER SCALE
ASCENT. SO I EXPECT SOME CONVECTION TO FIRE IN C NY AND TO A
LESSER EXTENT NE PA THIS AFTERNOON INTO THE EVENING.
NEXT QUESTION IS HOW WIDESPREAD? THE LATEST MESOSCALE CONVECTIVE
ALLOWING MODELS DO SHOW SCT ACVTY THIS AFTERNOON MAINLY IN CNTRL
AND WRN NY BUT VARY IN HOW WIDESPREAD THE ACVTY IS. LOOKING AT
VSBL SATELLITE IMAGERY YOU CAN SEE A CUMULUS FIELD EVOLVING ACRS C
AND WRN NY WITH SOME CLUMPING APPARENT IN A FEW SPOTS. GIVEN THAT
THE UPPER LEVEL WAVE IS RATHER WEAK AND THERE IS NO WELL DEFINED
BOUNDARIES I WILL LIMIT POPS FROM SLGHT CHC FOR TSRA THIS
AFTERNOON FOR C AND NC NY. I WILL PEAK THE POPS AT CHC IN OUR
HIGHER TERRAIN OF CNTRL NY WHERE MTNS ADD TO THE UPDRAFTS. GIVEN
THE POTENTIAL HIGH CAPES AND DRY AIR AT MID-LEVELS...THERE CUD BE
A STRONG STORM OR TWO. LOCAL CHECKLIST RETURNS MAINLY ISOLATED PULSE SEVERE
STORMS USING SYR NAM SOUNDING. SO I WILL MENTION CHC FOR STRONG TO
ISOLATED SEVERE STORM IN HWO FOR AFTERNOON.
AFTER SUNSET...ACVTY SHUD WIND DOWN WITH LOSS OF DAY/S HEATING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
500 AM UPDATE...
A COLD FRONT NOW OVER THE UPPER MIDWEST WILL MOVE INTO WESTERN NY
BY 0Z WEDNESDAY. AHEAD OF THIS TRIGGER WILL BE A RIPE ATMOSPHERE
WITH DAYTIME HIGHS IN THE UPPER 80S TO LOWER 90S AND DEWPOINTS
NEAR 70. THIS WILL TRANSLATE TO PLENTY OF INSTABILITY AND
POTENTIAL JUICE FOR STORMS WITH CAPES AROUND 2000 J/KG. WITH 0-6
KM SHEAR LACKING A BIT (25 KTS) AND A WARM/HUMID ATMOSPHERE, LARGE
HAIL DOES NOT APPEAR TO BE A PRIMARY RISK. DAMAGING WINDS WILL BE
A MUCH GREATER THREAT WITH VERY DRY AIR BETWEEN 700 AND 500 MB AND
STRONG LOW TO MID LEVEL SHEAR, SUPPORTING THE POSSIBILITY OF BOW ECHOES.
IN ADDITION TO THE WIND THREAT, VERY HEAVY RAIN WILL BE LIKELY
WITH FLASH FLOODING A CONCERN WITH PWATS (A MEASURE OF MOISTURE IN
THE ATMOSPHERE) OVER 2 INCHES, OR OVER 200% OF NORMAL! OUR SEVERE
WEATHER CHECKLIST HAS MANY PAST ANALOGS OF A BROKEN LINE OF
THUNDERSTORMS AS THE MAIN STORM MODE, WITH A FEW PULSE STORMS
POSSIBLE OUT AHEAD OF THE LINE. CONFIDENCE IN A BROKEN LINE OF
STORMS AS THE STORM MODE IS HIGHER THAN AVERAGE GIVEN THE AMOUNT
OF MATCHES IN THE DATABASE. BASED ON TIMING THIS SHOULD MOVE INTO
THE CWA BETWEEN 20Z AND 24Z. WILL CONTINUE TO HIGHLIGHT THE
DAMAGING WIND AND HEAVY RAIN THREAT IN THE HWO. WILL ALSO ADD
MENTION OF GUSTY WINDS AND HEAVY RAIN TO THE FORECAST LATE TUESDAY
(MAINLY NY STATE) AS SPC HAS MOST OF THE AREA IN A SLIGHT RISK.
THE COLD FRONT MENTIONED ABOVE MOVES THROUGH PART OF THE AREA
WEDNESDAY, BUT MAY HANG UP OVER NEPA. THIS WILL KEEP
SHOWERS/STORMS AROUND BOTH WEDNESDAY AND WEDNESDAY NIGHT.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
320 AM UPDATE...
MINOR FORECAST ADJUSTMENTS WERE MADE ACCOUNTING FOR LATEST WPC
GUIDANCE AND MODEL RUNS. MODELS STILL SHOW INCOMING SURFACE COLD
FRONT BECOMING NEARLY FLOW PARALLEL WITH TIME...SO THE FRONT
STRUGGLES TO PRESS THROUGH THE REGION BEFORE APPROACHING LONGWAVE
TROUGH FINALLY KICKS IT THROUGH. CONCERNS REMAIN FOR LOCALIZED
HEAVY RAINFALL AND POTENTIAL FOR STRONG THUNDERSTORMS...AS
DISCUSSED BELOW.
PREVIOUS DISCUSSION...
GLOBAL MODELS AND ENSEMBLES REMAIN CONSISTENT IN SUGGESTING AN
AMPLIFYING LONGWAVE TROF PATTERN ACROSS THE GREAT LAKES AND UPPER
MIDWEST THIS WEEK WHICH IS EXPECTED TO TRANSPORT DEEPER MOISTURE
FROM THE GULF STATES INTO THE NORTHEAST THROUGH THURSDAY. A COLD
FRONTAL PASSAGE IS STILL EXPECTED DURING THE THURSDAY-THURSDAY
NIGHT TIME FRAME OFFERING UP THE FINAL ROUNDS OF SHOWER AND
THUNDERSTORM ACTIVITY FOR THE REGION. ANY CONVECTIVE ACTIVITY IN
THIS AIRMASS WOULD BE CONDUCIVE TO LOCALLY HEAVY RAINFALL. DEEP
BULK SHEAR MAY ALSO BECOME FAVORABLE FOR STRONG THUNDERSTORMS...
BUT AT THIS POINT IN TIME...THIS IS LOW CONFIDENCE. THEN...A BROAD
AND UNSEASONABLY FRESH AREA OF CANADIAN HIGH PRESSURE IS FORECAST
TO BUILD IN FROM FRIDAY THROUGH THE HOLIDAY WEEKEND...WITH FAIR
SKIES AND HIGH TEMPERATURES IN THE 70S AND LOWS IN THE 50S.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
12Z UPDATE...
MAINLY VFR FOR TAF PERIOD...EXCEPT SOME MIST/VALLEY
FOG POTENTIAL DURING PREDAWN HOURS OF TUESDAY MORNING...AND BRIEF
RESTRICTIONS NOT OUT OF THE QUESTION FROM SCATTERED
SHOWERS/ISOLATED STORM TODAY. WITH MOIST ATMOSPHERE...SMALL UPPER
WAVES HAVE GENERATED A COUPLE BANDS OF LIGHT SHOWERS...YET
WEAKENING WHILE RUNNING INTO OUR CURRENT RIDGE. ONCE NOMINAL AMOUNT
OF INSTABILITY GETS GOING WITH HEATING LATE MORNING THROUGH
AFTERNOON...MOISTURE LEVELS WILL ALSO BE QUICKLY DROPPING AS
WEAKENING WAVE HEADS EAST. ALL TOLD...A FEW BRIEF SHOWERS EXPECTED
AT SEVERAL TERMINALS AS INDICATED VIA TEMPO GROUPS THIS MORNING TO
EARLY AFTERNOON...BUT THUNDER POTENTIAL IS MORE MUTED AND NOT
INCLUDED IN ANY TAF AT THIS TIME. BKN CLOUD DECKS TO BECOME MORE
SCT OR EVEN FEW LATE AFTERNOON INTO EVENING WITH DRIER AIR BEHIND
THE WEAKENING WAVE. WINDS S TO SSW 5-8 KTS BY DAY...VARIABLE TO
SSW 2-6 KTS BY NIGHT EXCEPT SE 5 KTS KRME THIS MORNING. KAVP/KELM
MVFR VIS LATE TONIGHT...WITH POTENTIAL FOR IFR VIS VALLEY FOG KELM
TOWARDS DAWN.
OUTLOOK...
TUE THROUGH TUE NGT...BRIEF RESTRICTIONS IN SCT SHRA/TSRA...BEST
POTENTIAL TUE AFTN-EVE. POSSIBLE VALLEY FOG KELM AGAIN TUE NGT.
WED THROUGH THU...RESTRICTIONS FROM RA/TSRA AS MOIST COLD FRONT
MOVES THROUGH THE REGION...ESPECIALLY LATE WED TO EARLY THU.
THU NGT THROUGH FRI...VFR EXCEPT POSSIBLE VALLEY FOG KELM.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN/HEDEN
NEAR TERM...DJN
SHORT TERM...HEDEN
LONG TERM...JAB/MDP
AVIATION...MDP
PREVIOUS FORECAST DISCUSSION BELOW...
OLD MCV FROM THIS AFTERNOON ALMOST DISCERN ABLE ACROSS KY OTHER
THAN SOME MID AND HI DECK. MUCH OF THE REGION IS PRECIP FREE AND
EXPECT THIS TO HOLD INTO MORNING HOURS FOR MOST PART...BUT FELT
PRUDENT TO LEAVE ISOLATED WORDING IN WX GRIDS ESPECIALLY ACROSS
THE N MOUNTAINS WHERE HI RES MODELS TRY TO FIRE SOME SHRA IN THE
PREDAWN BL COOLING. ANY MORNING LOW STRATUS/FG WILL LIFT INTO CU FIELD IN
MOISTURE LADEN ATMOSPHERE. SUBTLE RIPPLE IN THE FLOW WILL DAMPEN
OUT AS AXIS CROSSES TODAY...WITH DRYING IN MID LEVELS ARRIVING
FROM THE W AS THE DAY PROGRESSES. HOWEVER...EXPECT SCT SHRA/TSRA
TO DEVELOP BEFORE THIS OCCURS ACROSS MAINLY WV/SW VA ZONES. TRIED
TO DRY OUT MOST AREAS BY LATE AFTERNOON. EXPECT A DRY BUT MUGGY
NIGHT TONIGHT.
FOR TEMPS FOLLOWED LOCAL IN HOUSE MOS FAIRLY CLOSE GIVEN ITS
BETTER VERIFICATION OVER PAST WEEK. THIS ESSENTIALLY RESULTED IN
READINGS SIMILAR TO YESTERDAY. SAME REASONING FOR TONIGHT WITH
GENERALLY UPPER 60S FOR LOWS.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY/...
MODELS SHOWING 850 MB TEMPERATURES HITTING 21/22 C ON TUESDAY. THIS
COULD PROVIDE THE HOTTEST DAY OF THE SUMMER SO FAR. THIS ALSO
CREATES A VERY UNSTABLE SOUNDING WITH A BOUNDARY APPROACHING FROM
THE WEST. DRY AIR CAP SHOULD HOLD BACK ANY CONVECTION UNTIL THE
BOUNDARY ARRIVES. IF THUNDERSTORMS ARE ABLE TO FORM...SEVERE WEATHER
IS A POSSIBILITY.
MODELS SHOWING MUCH MORE MOISTURE OVER THE AREA ON WEDNESDAY...SO
EXPECT SCATTERED THUNDERSTORMS TO FORM DURING THE AFTERNOON AND
EVENING HOURS.
MOISTURE GRADUALLY PULLS EASTWARD ON THURSDAY WITH HIGH PRESSURE
BUILDING IN FROM THE WEST.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
FCST SHIFTED JUST ABOUT AN ENTIRE DAY FORWARD BETWEEN 00Z SAT AND
12Z SUN MODELS RUNS /THREE MAJOR CYCLES/. STILL HAVE THE CHANCE FOR
THUNDER THU WITH SOMEWHAT UNSTABLE AIR HANGING ON AS THE FRONT MIXES
THROUGH.
OTHERWISE MODELS SHOW STRONG UPPER LEVEL HIGH PRESSURE BUILDING OVER
THE WESTERN AND CENTRAL CONUS FOR LATE IN THE WORK WEEK AND NEXT
WEEKEND...WHICH IN TURN ALLOWS TROUGHING TO BECOME ESTABLISHED IN
THE E. THIS ALLOWS CANADIAN HIGH PRESSURE TO BECOME ESTABLISHED
OVER THE AREA...WITH A FRESHER AIR MASS. GFS DOES SHOW MOISTURE
CLOSE BY TO THE S AND E NEXT WEEKEND...ALTHOUGH THAT IS TANGENTIALLY
IF AT ALL RELATED TO THE TROPICAL SYSTEM MOVING OFFSHORE THEN.
BLENDED IN WPC FOR HIGHS THU AND GFS-BASED MOS FOR LOWS THU NT...A
BIT HIGHER THAN PREVIOUS IN BOTH CASES WITH THE SLOWER TIMING ON THE
FRONTAL PASSAGE. BLENDED IN ECMWF DATA FOR MOST OF THE REMAINING
HIGHS AND LOWS WITH THE COOLEST WEATHER NOW PUSHED BACK TO FRI AND
FRI NT...NOT FAR FROM WPC GUIDANCE. THE EXTENDED FCST IS CLOSEST TO
THE ECMWFHIRES SOLN FROM WPC AND LOCALLY.
&&
.AVIATION /10Z MONDAY THROUGH FRIDAY/...
ANY FG OR STRATUS WILL QUICKLY LIFT WITH SUNRISE. ELECTED TO HOLD
A BIT LONGER ALONG OH RIVER AND INTO SE OH...TO AFFECT KHTS/KPKB
TERMINALS THIS MORNING. LINGERING RIPPLE IN THE MID LEVELS SHOULD
BE ENOUGH FOR SCT SHRA/TSRA THIS AFTERNOON...GENERALLY ALONG AND E
OF I79 CORRIDOR...WITH ISOLATED COVERAGE ELSEWHERE EARLY THIS
AFTERNOON.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z TUESDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: MAY BE TOO PESSIMISTIC WITH STRATUS FOR
KHTS/KPKB THIS MORNING.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 11 12 13 14 15 16 17 18 19 20 21 22
EDT 1HRLY 07 08 09 10 11 12 13 14 15 16 17 18
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY M M M M H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY M M M M H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z TUESDAY...
IFR CONDITIONS POSSIBLE IN ROUNDS OF THUNDERSTORMS INTO WEDNESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...RPY/30
NEAR TERM...30
SHORT TERM...RPY
LONG TERM...TRM
AVIATION...30
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1026 AM CDT MON JUN 30 2014
.UPDATE...MORNING UPDATE.
&&
.DISCUSSION...
TEMPERATURES ARE WARMING QUICKLY ACROSS THE MIDSOUTH ALTHOUGH SOME
THIN STRATUS IS PROBABLY HELPING TO KEEP CONDITIONS SLIGHTLY
COOLER THAN WHAT THEY COULD BE. ABUNDANT GROUND MOISTURE IS
RESULTING IN HIGH HUMIDITY...AND ENHANCED HEAT INDICES.
TEMPERATURES WILL LIKELY TOP OUT IN THE LOW TO MIDDLE 90S THIS
AFTERNOON WITH HEAT INDICES AROUND 100. NO RAIN IS EXPECTED.
&&
.PREV DISCUSSION... /ISSUED 621 AM CDT MON JUN 30 2014/
CURRENTLY...A WEAK LEFTOVER BOUNDARY STRETCHES NW/SE ACROSS WEST
TENNESSEE THIS MORNING. THE HRRR HAS BEEN TRYING TO DEVELOP
CONVECTION INVOF THIS BOUNDARY OVERNIGHT BUT THE 850 MB FLOW OF
15-20 KTS DOES NOT SEEM TO BE ENOUGH TO GENERATE ANY CONVECTION
WEST OF THE TN RIVER. SKIES RANGE FROM MOSTLY CLEAR IN THE WEST TO
MOSTLY CLOUDY NEAR THE TN RIVER. VERY MOIST AND WARM ACROSS THE
DELTA WHERE DEWPOINTS ARE IN THE MID 70S.
TODAY...WILL LEAVE A SMALL POPS ALONG THE TN RIVER VALLEY THIS
MORNING TO COVER ANY POTENTIAL DEVELOPMENT. THE BIG STORY TODAY IS
THE UPPER RIDGE BUILDING INTO THE AREA WITH INCREASINGLY HOT AND
HUMID CONDITIONS. EXPECT DEWPOINTS TO REMAIN QUITE HIGH TODAY DUE
TO ALL THE RECENT RAINS. THE 00Z NAM IS A LITTLE LESS AGGRESSIVE
WITH 925 MB TEMPS THAN PREVIOUS RUNS SO BACKED OFF HIGHS ABOUT A
DEGREE. THE ADDED LOW LEVEL MOISTURE DUE TO RECENT RAIN WILL MAKE
UP FOR IT AS DEWPOINTS WILL REMAIN IN THE MID 70S THIS MORNING
BEFORE MIXING OUT A BIT THIS AFTERNOON. HEAT INDEX VALUES WILL HIT
100F BY ABOUT NOON.
TONIGHT...WARM AND MUGGY WITH MOSTLY CLEAR SKIES. LOWS WILL BE IN
THE LOWER TO MID 70S.
TUESDAY...ANOTHER HOT AND HUMID DAY. TEMPS WILL CLIMB A COUPLE
DEGREES HIGHER PUSHING HEAT INDEX VALUES IN THE LOW 100S WITH
PLENTY OF SUNSHINE. AN UPPER TROF PUSHING THROUGH THE GREAT LAKES
WILL PUSH A COLD FRONT TOWARD THE MIDSOUTH IN THE AFTERNOON
PERHAPS BRINGING SOME SHOWERS AND THUNDERSTORMS TO NORTHERN
LOCATIONS. THE AIRMASS WILL BE QUITE UNSTABLE AND A FEW STRONG
STORMS ARE POSSIBLE ACROSS THE NORTH.
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...00Z MODELS INDICATE THE
GREAT LAKES TROF WILL BE A LITTLE DEEPER AND EXTEND A LITTLE
FURTHER INTO THE SOUTHERN STATES BY WEDNESDAY WHICH HELPS DRIVE
THE FRONT THROUGH MORE QUICKLY ON WEDNESDAY. SHOWER/THUNDERSTORM
CHANCES WILL MOVE SOUTH TUESDAY NIGHT AND WEDNESDAY WITH THE
FRONT. BY WEDNESDAY EVENING MOST OF THE PRECIP WILL HAVE EXITED
THE REGION. MODELS ARE INDICATING A GOOD DEAL OF INSTABILITY
ACROSS THE AREA THOUGH WIND SHEAR IS FAIRLY WEAK AT THE SOUTHERN
END OF THE UPPER TROF. A FEW STRONG STORMS ARE POSSIBLE ACROSS THE
AREA AS THE FRONT MOVES THROUGH.
THURSDAY THROUGH SUNDAY...HIGH PRESSURE INTO THE AREA ON THURSDAY
AND CONTINUE INTO THE WEEKEND. BELOW NORMAL TEMPERATURES ARE
EXPECTED WITH HIGHS IN THE 80S THURSDAY AND FRIDAY AND LOWS IN THE
60S. MAY EVEN SEE SOME 50S IN THE TYPICAL COOLER SPOTS. TEMPS WILL
BEGIN TO WARM BACK INTO THE LOWER 90S BY SUNDAY.
SJM
&&
.AVIATION...12Z TAFS
MAIN AVIATION CONCERN WILL BE GUSTY SOUTHWEST WINDS DEVELOPING AT
MEM..JBR AND MKL. WINDS WILL FREQUENTLY GUST IN THE 16-22 KT
RANGE DEPENDING ON SITE. OTHERWISE CONDITIONS WILL BE VFR.
JAB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
621 AM CDT MON JUN 30 2014
.UPDATE...
UPDATED FOR 12Z AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 307 AM CDT MON JUN 30 2014/
DISCUSSION...
CURRENTLY...A WEAK LEFTOVER BOUNDARY STRETCHES NW/SE ACROSS WEST
TENNESSEE THIS MORNING. THE HRRR HAS BEEN TRYING TO DEVELOP
CONVECTION INVOF THIS BOUNDARY OVERNIGHT BUT THE 850 MB FLOW OF
15-20 KTS DOES NOT SEEM TO BE ENOUGH TO GENERATE ANY CONVECTION
WEST OF THE TN RIVER. SKIES RANGE FROM MOSTLY CLEAR IN THE WEST TO
MOSTLY CLOUDY NEAR THE TN RIVER. VERY MOIST AND WARM ACROSS THE
DELTA WHERE DEWPOINTS ARE IN THE MID 70S.
TODAY...WILL LEAVE A SMALL POPS ALONG THE TN RIVER VALLEY THIS
MORNING TO COVER ANY POTENTIAL DEVELOPMENT. THE BIG STORY TODAY IS
THE UPPER RIDGE BUILDING INTO THE AREA WITH INCREASINGLY HOT AND
HUMID CONDITIONS. EXPECT DEWPOINTS TO REMAIN QUITE HIGH TODAY DUE
TO ALL THE RECENT RAINS. THE 00Z NAM IS A LITTLE LESS AGGRESSIVE
WITH 925 MB TEMPS THAN PREVIOUS RUNS SO BACKED OFF HIGHS ABOUT A
DEGREE. THE ADDED LOW LEVEL MOISTURE DUE TO RECENT RAIN WILL MAKE
UP FOR IT AS DEWPOINTS WILL REMAIN IN THE MID 70S THIS MORNING
BEFORE MIXING OUT A BIT THIS AFTERNOON. HEAT INDEX VALUES WILL HIT
100F BY ABOUT NOON.
TONIGHT...WARM AND MUGGY WITH MOSTLY CLEAR SKIES. LOWS WILL BE IN
THE LOWER TO MID 70S.
TUESDAY...ANOTHER HOT AND HUMID DAY. TEMPS WILL CLIMB A COUPLE
DEGREES HIGHER PUSHING HEAT INDEX VALUES IN THE LOW 100S WITH
PLENTY OF SUNSHINE. AN UPPER TROF PUSHING THROUGH THE GREAT LAKES
WILL PUSH A COLD FRONT TOWARD THE MIDSOUTH IN THE AFTERNOON
PERHAPS BRINGING SOME SHOWERS AND THUNDERSTORMS TO NORTHERN
LOCATIONS. THE AIRMASS WILL BE QUITE UNSTABLE AND A FEW STRONG
STORMS ARE POSSIBLE ACROSS THE NORTH.
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...00Z MODELS INDICATE THE
GREAT LAKES TROF WILL BE A LITTLE DEEPER AND EXTEND A LITTLE
FURTHER INTO THE SOUTHERN STATES BY WEDNESDAY WHICH HELPS DRIVE
THE FRONT THROUGH MORE QUICKLY ON WEDNESDAY. SHOWER/THUNDERSTORM
CHANCES WILL MOVE SOUTH TUESDAY NIGHT AND WEDNESDAY WITH THE
FRONT. BY WEDNESDAY EVENING MOST OF THE PRECIP WILL HAVE EXITED
THE REGION. MODELS ARE INDICATING A GOOD DEAL OF INSTABILITY
ACROSS THE AREA THOUGH WIND SHEAR IS FAIRLY WEAK AT THE SOUTHERN
END OF THE UPPER TROF. A FEW STRONG STORMS ARE POSSIBLE ACROSS THE
AREA AS THE FRONT MOVES THROUGH.
THURSDAY THROUGH SUNDAY...HIGH PRESSURE INTO THE AREA ON THURSDAY
AND CONTINUE INTO THE WEEKEND. BELOW NORMAL TEMPERATURES ARE
EXPECTED WITH HIGHS IN THE 80S THURSDAY AND FRIDAY AND LOWS IN THE
60S. MAY EVEN SEE SOME 50S IN THE TYPICAL COOLER SPOTS. TEMPS WILL
BEGIN TO WARM BACK INTO THE LOWER 90S BY SUNDAY.
SJM
&&
.AVIATION...
12Z TAFS
MAIN AVIATION CONCERN WILL BE GUSTY SOUTHWEST WINDS DEVELOPING AT
MEM..JBR AND MKL. WINDS WILL FREQUENTLY GUST IN THE 16-22 KT
RANGE DEPENDING ON SITE. OTHERWISE CONDITIONS WILL BE VFR.
JAB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
743 AM EDT MON JUN 30 2014
.SYNOPSIS...
HIGH PRESSURE WILL SHIFT EAST THROUGH TUESDAY...ALLOWING MORE OF A
SOUTHWEST FLOW TO DEVELOP. COLD FRONT ARRIVES MIDWEEK SHOULD BE
JUST EAST OF THE AREA BY THE HOLIDAY WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 700 AM EDT MONDAY...
ONLY MINOR ADJUSTMENTS MADE TO THE FORECAST THIS MORNING...MAINLY
TO ADJUST RAIN CHANCES THROUGH LATE MORNING AND TO TWEAK CLOUD
COVER...BOTH BASED ON LATEST RADAR/SATELLITE TRENDS RESPECTIVELY.
THE REST OF THE EARLY MORNING FORECAST PACKAGE APPEARS TO BE ON
TRACK.
AS OF 300 AM EDT MONDAY...
UPPER LEVELS SHOWING SHORTWAVE WEAKENING AS IT ENTERS THE MTNS THIS
MORNING WITH MAIN TROUGH OVER THE UPPER MS VALLEY. STILL...ENOUGH
BACKING ALOFT AND SFC CONVERGENCE TO ALLOW FOR SHOWERS AND STORMS TO
FORM AFTER MID-LATE MORNING IN THE MTNS. FOLLOWED THE 3Z RAP EARLY...
THEN TRANSITION TOWARD BLEND OF GFS/CMC/EC. STILL NOT TOO EXCITED
ABOUT GOING HIGHER THAN 50 POPS TODAY...BUT AT LEAST THE WRN CWA
WILL BE IN AN INVERTED SFC TROUGH TO ALLOW FOR GOOD COVERAGE...
WHILE THE PIEDMONT STAYS SITUATED WITHIN A WEAKENING WEDGE.
THE STORM PREDICTION CENTER SHOWS THE NC MTNS INTO THE SRN VA BLUE
RIDGE WITH 5 PERCENT THREAT OF WIND DAMAGE. MODEL SOUNDINGS SUGGEST
HIGHER CAPES TODAY...WITH PWATS RUNNING ABOUT 150 PERCENT OF
NORMAL...WET MICROBURSTS ARE POSSIBLE. WILL HIGHLIGHT IN HWO. IN
ADDITION...WIND FLOW REMAINS WEAK SO HEAVY RAINS/FLASH FLOODING TO
BE CONCERNED ABOUT ESPECIALLY IN THE FAR SW CWA WHERE FLOODING
OCCURRED IN SMYTH COUNTY SUNDAY. STILL EXPECT ISOLATED THREAT SO NO
WATCH AT THIS TIME.
HIGHS TODAY WILL BE DEPENDENT ON CLOUDS. THINK NEAR NORMAL HIGHS
WITH HIGHER MOISTURE CONTENT IN THE AIR WILL KEEP TEMPS IN THE
80S...SIMILAR TO SUNDAY.
TONIGHT...THE COVERAGE FOR SHRA/TSRA DIMINISHES ALTHOUGH SHORTWAVE
TROUGH LINGERS IN THE MTNS...SO ISOLATED SHOWERS MAY STICK AROUND
PAST MIDNIGHT THROUGH THE WEST. EXPECT LOWS TO STAY ELEVATED IN THE
60S...TO AROUND 70 SOUTHEAST.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
AS OF 345 AM EDT MONDAY...
FOR TUESDAY...UPPER LEVEL RIDGING WILL BUILD SLIGHTLY NORTH ALONG
THE ATLANTIC COAST IN RESPONSE TO A DEEP UPPER LEVEL TROUGH DIGGING
ACROSS THE UPPER MIDWEST. WILL START THE DAY WITH A LIGHT WEST
SOUTHWEST WIND COMING OFF THE MOUNTAINS AS A WEAK SURFACE TROUGH
DEVELOPS ALONG THE LEE OF THE BLUE RIDGE...AND BELIEVE THE DOWNSLOPE
FLOW WILL BE ENOUGH TO INHIBIT MORE THAN ISOLATED CONVECTION THROUGH
EARLY AFTERNOON. BY MID AFTERNOON HOWEVER...THE COMBINATION OF
MAXIMUM DAYTIME HEATING AND INCREASING CONVERGENCE AS A COLD FRONT
APPROACHES FROM THE WEST WILL BE ENOUGH TO TRIGGER SPOTTY SHOWERS
AND THUNDERSTORMS...WITH GREATER COVERAGE FOUND ALONG AND EAST OF
THE BLUE RIDGE. CONVECTION WILL BE PULSE VARIETY...HIT AND MISS IN
NATURE. MAY HAVE ENOUGH INSTABILITY FOR A COUPLE STRONG TO SEVERE
STORMS BY EARLY EVENING. THE COLD FRONT WILL LOSE ITS EASTWARD PUSH
BY LATE EVENING...STALLING NEAR THE OHIO RIVER. MAY SEE SOME SHOWER
AND THUNDERSTORM ACTIVITY ASSOCIATED WITH THE FRONT APPROACH THE
WESTERN RIDGES AFTER SUNSET...WITH THIS ACTIVITY WEAKENING AS IT
ADVANCES.
THE LEE SIDE TROUGH WILL REMAIN IN PLACE FOR WEDNESDAY...AND EXPECT
GREATER INSTABILITY AS THE UPPER LEVEL TROUGH MOVES ACROSS THE GREAT
LAKES...BRINGING COOLER AIR ALOFT OVER OUR REGION. STILL EXPECT
STORMS TO DEVELOP IN A PULSE HIT AND MISS NATURE...BUT SEE A
STRONGER POTENTIAL FOR SEVERE THUNDERSTORMS AS AFTERNOON
TEMPERATURES REACH INTO THE MID 90S ACROSS THE SOUTHSIDE...WHILE THE
MOUNTAINS CLIMB INTO THE MID 80S. CONVECTION IS ALSO EXPECTED TO GET
OFF TO AN EARLIER START...WITH SOME SHOWERS AND THUNDERSTORMS
DEVELOPING BY LATE MORNING. FORECAST SOUNDINGS INDICATE PLENTY OF
DRY AIR IN THE MID LEVELS OF THE ATMOSPHERE...AND WITH CAPES
EXPECTED TO REACH 2000-2500 J/KG...EXPECT THE STRONGER STORMS WILL
BE CAPABLE OF PRODUCING GUSTY WINDS AS THE MAIN THREAT...AND LARGE
HAIL MORE AS A SECONDARY...BUT STILL SIGNIFICANT...THREAT.
ON THURSDAY...THE COLD FRONT TO OUR WEST WILL GET ANOTHER PUSH AS A
LOW PRESSURE SYSTEM PASSES ACROSS CANADA...BUT NOT SOON ENOUGH TO
BRING THE FRONT INTO OUR AREA. AS SUCH...EXPECT ANOTHER DAY OF
STRONG DAYTIME HEATING...WITH MORE STRONG SPOTTY SHOWERS AND
THUNDERSTORMS DEVELOPING DURING THE AFTERNOON AND EVENING. THURSDAY
WILL BE SLIGHTLY COOLER THAN WEDNESDAY...BUT STILL LOOKING FOR
LOW/MID 80S WEST TO LOW 90S EAST.
SOUTHWESTERLY FLOW WILL KEEP THE PIPELINE OF WARM MUGGY AIR FROM THE
GULF IN BUSINESS...AND EXPECT LOW TEMPERATURES FOR TUESDAY AND
WEDNESDAY NIGHT TO RANGE FROM THE MID 60S TO THE LOW 70S. PATCHY FOG
WILL BE POSSIBLE WHERE SKIES CLEAR AND SIGNIFICANT RAINFALL OCCURS.
THE COLD FRONT WILL CROSS THE APPALACHIANS LATE THURSDAY
NIGHT...WHICH WILL FINALLY BRING COOLER DRIER AIR TO OUR AREA.
AS OF 2 AM MONDAY...THE NATIONAL HURRICANE CENTER (NHC) GIVES THE
SURFACE LOW OFF THE ATLANTIC COAST OF FLORIDA A 60 PERCENT CHANCE OF
DEVELOPING INTO A TROPICAL CYCLONE OVER THE NEXT COUPLE DAYS. THIS
SYSTEM IS EXPECTED TO REMAIN OFF THE FLORIDA COAST THROUGH WEDNESDAY
NIGHT...BEFORE LIFTING NORTHEAST THURSDAY AS IT IS PICKED UP BY THE
UPPER LEVEL TROUGH CROSSING THE GREAT LAKES. AT THIS TIME...STILL
NOT EXPECTING ANY DIRECT IMPACT FROM THIS SYSTEM TO OUR FORECAST
AREA. SEE THE NHC WEBSITE FOR THE LATEST INFORMATION CONCERNING
FURTHER DEVELOPMENT OF THIS SYSTEM INTO A TROPICAL CYCLONE.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 300 PM EDT SUNDAY...
SFC HIGH PRESSURE WILL BUILD SOUTH INTO OUR REGION ON
FRIDAY...WITH DRIER AND MORE STABLE AIR MASS. THERE ARE SOME
CONCERNS THAT SUBTROPICAL RIDGE AND PLACEMENT OF THE FRONT TO OUR
SOUTH AND ITS ASSOCIATED DEEPER MOISTURE...COULD TRIGGERS A FEW
SHOWERS AND THUNDERSTORMS ACROSS SOUTHERN EASTERN PORTIONS OF
FORECAST AREA FRIDAY AFTERNOON INTO FRIDAY EVENING.
LOW WILL SLOWLY LIFT NORTHEAST OFF THE COAST SATURDAY INTO SATURDAY
NIGHT. ITS IMPACTS TO THE MID-ATLANTIC COAST APPEAR MINIMAL AS
MODELS PUSH IT OUT TO SEA. WITH SOME LOW LEVEL MOISTURE STILL IN OUR
REGION...DECIDED TO USED HPCGUIDE LIGHT POPS FOR THE HOLIDAY WEEKEND.
TEMPERATURES EXPECTED TO BE NEAR NORMAL FOR THE HOLIDAY WEEKEND.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
AS OF 730 AM EDT MONDAY...
SATELLITE IMAGERY INDICATES SCATTERED LOW AND MID CLOUDS WORKING
ACROSS THE AREA FROM THE WEST. THE INCREASING CLOUD COVER HAS
HELPED TO ERODE EARLY MORNING FOG IN A FEW AREAS...WITH ALL TAF
SITES NOW REPORTING VISIBILITIES 6SM OR BETTER. ONLY KLWB
REPORTING MVFR CEILINGS AT THIS POINT...ALTHOUGH KBCB/KBLF MAY
HAVE LOWER CEILINGS PASS OVERHEAD THROUGH 14Z.
THE THREAT OF SHOWERS REMAINS MINIMAL THIS MORNING...BUT EXPECT
THE BEST RAIN SHOWER/STORM THREAT TO ARRIVE BY MIDDAY/17Z IN THE
MOUNTAINS TO AFFECT KLWB/KBLF...THEN SHIFT EAST TOWARD KROA/KBCB
BY 18Z-20Z. COVERAGE IS STILL EXPECTED TO BE SPOTTY HIT AND
MISS...SO LEFT PREDOMINANT THUNDER/SHOWERS OUT OF THE TAFS.
HOWEVER...WHERE RAINFALL DOES OCCUR...IT MAY BE HEAVY...LIMITING
VISIBILITIES TO LESS THAN 1SM. LIGHT WINDS ALOFT WILL ALSO
TRANSLATE TO SLOWER MOVING CELLS...WHICH MAY LINGER OVER AN
AIRPORT FOR EXTENDED PERIODS OF TIME. HIGH PRESSURE IS SUPPORTING
MORE STABLE CONDITIONS/LESS COVERAGE FURTHER EAST FOR KDAN/KLYH...
SO HAVE NO MENTION OF CONVECTION FOR THESE TAF SITES FOR NOW.
MODELS INDICATE CONVECTION WANING DURING THE 22Z-00Z TIMEFRAME...
SO HAVE REMOVED MENTION FROM TAFS AFTER THIS TIME...ALTHOUGH
ISOLATED RESIDUAL SHOWERS MAY STILL REMAIN FOR A FEW HOURS.
EXPECT A REPEAT OF VFR CONDITIONS INTERMIXED WITH LOW MVFR/IFR
ACROSS THE MOUNTAINS TONIGHT. IF CLOUDS CLEAR OUT FROM
KLWB...DENSE FOG WILL BE HIGHLY LIKELY. FOG ALSO POSSIBLE AT KBCB
AND ANYWHERE THAT RECEIVES SIGNIFICANT RAINFALL THIS EVENING.
EXTENDED AVIATION...
A BREAK IN THE CONVECTION OCCURS TUESDAY...THOUGH CANNOT FULLY
RULE OUT ISOLATED SHRA/TSRA IN THE MTNS.
FRONTAL BOUNDARY AND UPPER TROUGH HEAD EAST INTO THE AREA BY
MIDWEEK...WITH GOOD CHANCE OF SHOWERS AND STORMS. THE MAJORITY OF
THE DAYS WILL BE VFR EXCEPT DURING STORMS AND AT NIGHT WITH MVFR
CIGS/VSBY POSSIBLE. FRONT SLOWS DOWN PER LOW PRESSURE/TROPICAL LOW
STRENGTHENING OFF THE COAST OF THE CAROLINAS BY THURSDAY-FRIDAY.
THIS WILL KEEP THE SHRA/TSRA THREAT AT LEAST THURSDAY...THOUGH
FRIDAY COULD BE DRY WITH SUBSIDENCE IF THE OFFSHORE LOW DEEPENS
ENOUGH INTO A TROPICAL CYCLONE. SEE NHC PRODUCTS FOR DETAILS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...WP
NEAR TERM...NF/WP
SHORT TERM...NF
LONG TERM...KK
AVIATION...NF/WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
706 AM EDT MON JUN 30 2014
.SYNOPSIS...
HIGH PRESSURE WILL SHIFT EAST THROUGH TUESDAY...ALLOWING MORE OF A
SOUTHWEST FLOW TO DEVELOP. COLD FRONT ARRIVES MIDWEEK SHOULD BE
JUST EAST OF THE AREA BY THE HOLIDAY WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 700 AM EDT MONDAY...
ONLY MINOR ADJUSTMENTS MADE TO THE FORECAST THIS MORNING...MAINLY
TO ADJUST RAIN CHANCES THROUGH LATE MORNING AND TO TWEAK CLOUD
COVER...BOTH BASED ON LATEST RADAR/SATELLITE TRENDS RESPECTIVELY.
THE REST OF THE EARLY MORNING FORECAST PACKAGE APPEARS TO BE ON
TRACK.
AS OF 300 AM EDT MONDAY...
UPPER LEVELS SHOWING SHORTWAVE WEAKENING AS IT ENTERS THE MTNS THIS
MORNING WITH MAIN TROUGH OVER THE UPPER MS VALLEY. STILL...ENOUGH
BACKING ALOFT AND SFC CONVERGENCE TO ALLOW FOR SHOWERS AND STORMS TO
FORM AFTER MID-LATE MORNING IN THE MTNS. FOLLOWED THE 3Z RAP EARLY...
THEN TRANSITION TOWARD BLEND OF GFS/CMC/EC. STILL NOT TOO EXCITED
ABOUT GOING HIGHER THAN 50 POPS TODAY...BUT AT LEAST THE WRN CWA
WILL BE IN AN INVERTED SFC TROUGH TO ALLOW FOR GOOD COVERAGE...
WHILE THE PIEDMONT STAYS SITUATED WITHIN A WEAKENING WEDGE.
THE STORM PREDICTION CENTER SHOWS THE NC MTNS INTO THE SRN VA BLUE
RIDGE WITH 5 PERCENT THREAT OF WIND DAMAGE. MODEL SOUNDINGS SUGGEST
HIGHER CAPES TODAY...WITH PWATS RUNNING ABOUT 150 PERCENT OF
NORMAL...WET MICROBURSTS ARE POSSIBLE. WILL HIGHLIGHT IN HWO. IN
ADDITION...WIND FLOW REMAINS WEAK SO HEAVY RAINS/FLASH FLOODING TO
BE CONCERNED ABOUT ESPECIALLY IN THE FAR SW CWA WHERE FLOODING
OCCURRED IN SMYTH COUNTY SUNDAY. STILL EXPECT ISOLATED THREAT SO NO
WATCH AT THIS TIME.
HIGHS TODAY WILL BE DEPENDENT ON CLOUDS. THINK NEAR NORMAL HIGHS
WITH HIGHER MOISTURE CONTENT IN THE AIR WILL KEEP TEMPS IN THE
80S...SIMILAR TO SUNDAY.
TONIGHT...THE COVERAGE FOR SHRA/TSRA DIMINISHES ALTHOUGH SHORTWAVE
TROUGH LINGERS IN THE MTNS...SO ISOLATED SHOWERS MAY STICK AROUND
PAST MIDNIGHT THROUGH THE WEST. EXPECT LOWS TO STAY ELEVATED IN THE
60S...TO AROUND 70 SOUTHEAST.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
AS OF 345 AM EDT MONDAY...
FOR TUESDAY...UPPER LEVEL RIDGING WILL BUILD SLIGHTLY NORTH ALONG
THE ATLANTIC COAST IN RESPONSE TO A DEEP UPPER LEVEL TROUGH DIGGING
ACROSS THE UPPER MIDWEST. WILL START THE DAY WITH A LIGHT WEST
SOUTHWEST WIND COMING OFF THE MOUNTAINS AS A WEAK SURFACE TROUGH
DEVELOPS ALONG THE LEE OF THE BLUE RIDGE...AND BELIEVE THE DOWNSLOPE
FLOW WILL BE ENOUGH TO INHIBIT MORE THAN ISOLATED CONVECTION THROUGH
EARLY AFTERNOON. BY MID AFTERNOON HOWEVER...THE COMBINATION OF
MAXIMUM DAYTIME HEATING AND INCREASING CONVERGENCE AS A COLD FRONT
APPROACHES FROM THE WEST WILL BE ENOUGH TO TRIGGER SPOTTY SHOWERS
AND THUNDERSTORMS...WITH GREATER COVERAGE FOUND ALONG AND EAST OF
THE BLUE RIDGE. CONVECTION WILL BE PULSE VARIETY...HIT AND MISS IN
NATURE. MAY HAVE ENOUGH INSTABILITY FOR A COUPLE STRONG TO SEVERE
STORMS BY EARLY EVENING. THE COLD FRONT WILL LOSE ITS EASTWARD PUSH
BY LATE EVENING...STALLING NEAR THE OHIO RIVER. MAY SEE SOME SHOWER
AND THUNDERSTORM ACTIVITY ASSOCIATED WITH THE FRONT APPROACH THE
WESTERN RIDGES AFTER SUNSET...WITH THIS ACTIVITY WEAKENING AS IT
ADVANCES.
THE LEE SIDE TROUGH WILL REMAIN IN PLACE FOR WEDNESDAY...AND EXPECT
GREATER INSTABILITY AS THE UPPER LEVEL TROUGH MOVES ACROSS THE GREAT
LAKES...BRINGING COOLER AIR ALOFT OVER OUR REGION. STILL EXPECT
STORMS TO DEVELOP IN A PULSE HIT AND MISS NATURE...BUT SEE A
STRONGER POTENTIAL FOR SEVERE THUNDERSTORMS AS AFTERNOON
TEMPERATURES REACH INTO THE MID 90S ACROSS THE SOUTHSIDE...WHILE THE
MOUNTAINS CLIMB INTO THE MID 80S. CONVECTION IS ALSO EXPECTED TO GET
OFF TO AN EARLIER START...WITH SOME SHOWERS AND THUNDERSTORMS
DEVELOPING BY LATE MORNING. FORECAST SOUNDINGS INDICATE PLENTY OF
DRY AIR IN THE MID LEVELS OF THE ATMOSPHERE...AND WITH CAPES
EXPECTED TO REACH 2000-2500 J/KG...EXPECT THE STRONGER STORMS WILL
BE CAPABLE OF PRODUCING GUSTY WINDS AS THE MAIN THREAT...AND LARGE
HAIL MORE AS A SECONDARY...BUT STILL SIGNIFICANT...THREAT.
ON THURSDAY...THE COLD FRONT TO OUR WEST WILL GET ANOTHER PUSH AS A
LOW PRESSURE SYSTEM PASSES ACROSS CANADA...BUT NOT SOON ENOUGH TO
BRING THE FRONT INTO OUR AREA. AS SUCH...EXPECT ANOTHER DAY OF
STRONG DAYTIME HEATING...WITH MORE STRONG SPOTTY SHOWERS AND
THUNDERSTORMS DEVELOPING DURING THE AFTERNOON AND EVENING. THURSDAY
WILL BE SLIGHTLY COOLER THAN WEDNESDAY...BUT STILL LOOKING FOR
LOW/MID 80S WEST TO LOW 90S EAST.
SOUTHWESTERLY FLOW WILL KEEP THE PIPELINE OF WARM MUGGY AIR FROM THE
GULF IN BUSINESS...AND EXPECT LOW TEMPERATURES FOR TUESDAY AND
WEDNESDAY NIGHT TO RANGE FROM THE MID 60S TO THE LOW 70S. PATCHY FOG
WILL BE POSSIBLE WHERE SKIES CLEAR AND SIGNIFICANT RAINFALL OCCURS.
THE COLD FRONT WILL CROSS THE APPALACHIANS LATE THURSDAY
NIGHT...WHICH WILL FINALLY BRING COOLER DRIER AIR TO OUR AREA.
AS OF 2 AM MONDAY...THE NATIONAL HURRICANE CENTER (NHC) GIVES THE
SURFACE LOW OFF THE ATLANTIC COAST OF FLORIDA A 60 PERCENT CHANCE OF
DEVELOPING INTO A TROPICAL CYCLONE OVER THE NEXT COUPLE DAYS. THIS
SYSTEM IS EXPECTED TO REMAIN OFF THE FLORIDA COAST THROUGH WEDNESDAY
NIGHT...BEFORE LIFTING NORTHEAST THURSDAY AS IT IS PICKED UP BY THE
UPPER LEVEL TROUGH CROSSING THE GREAT LAKES. AT THIS TIME...STILL
NOT EXPECTING ANY DIRECT IMPACT FROM THIS SYSTEM TO OUR FORECAST
AREA. SEE THE NHC WEBSITE FOR THE LATEST INFORMATION CONCERNING
FURTHER DEVELOPMENT OF THIS SYSTEM INTO A TROPICAL CYCLONE.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 300 PM EDT SUNDAY...
SFC HIGH PRESSURE WILL BUILD SOUTH INTO OUR REGION ON
FRIDAY...WITH DRIER AND MORE STABLE AIR MASS. THERE ARE SOME
CONCERNS THAT SUBTROPICAL RIDGE AND PLACEMENT OF THE FRONT TO OUR
SOUTH AND ITS ASSOCIATED DEEPER MOISTURE...COULD TRIGGERS A FEW
SHOWERS AND THUNDERSTORMS ACROSS SOUTHERN EASTERN PORTIONS OF
FORECAST AREA FRIDAY AFTERNOON INTO FRIDAY EVENING.
LOW WILL SLOWLY LIFT NORTHEAST OFF THE COAST SATURDAY INTO SATURDAY
NIGHT. ITS IMPACTS TO THE MID-ATLANTIC COAST APPEAR MINIMAL AS
MODELS PUSH IT OUT TO SEA. WITH SOME LOW LEVEL MOISTURE STILL IN OUR
REGION...DECIDED TO USED HPCGUIDE LIGHT POPS FOR THE HOLIDAY WEEKEND.
TEMPERATURES EXPECTED TO BE NEAR NORMAL FOR THE HOLIDAY WEEKEND.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
AS OF 130 AM EDT MONDAY...
MAINLY VFR THIS MORNING WITH SCATTERED LOW CLOUDS ACROSS THE MTNS.
THINK THE LOWER CIGS WILL STAY WEST OF THE BLUE RIDGE...WHILE
CANNOT RULE OUT MVFR FOG AT LYH/DAN AROUND 09-12Z.
THE THREAT OF SHOWERS WILL BE MINIMAL THIS MORNING...BUT EXPECT
THE BEST RAIN SHOWER/STORM THREAT TO ARRIVE BY MIDDAY/17Z IN THE
MTNS...THEN SHIFT EAST TOWARD ROA/BCB BY 18Z-20Z.
HOWEVER...COVERAGE TO BE SCATTERED SO LEFT PREDOMINANT
THUNDER/SHOWERS OUT OF THE TAFS. LESS COVERAGE EAST OF THE BLUE
RIDGE SO NOT EVEN VCTS SEEN HERE FOR NOW.
THE MORNINGS LOWER CIGS AND FOG WILL BE LIFTING INTO VFR CIGS BY
MID TO LATE MORNING...LAST AT BLF.
TOOK VCTS OUT OF THE TAFS AFTER 22Z...BUT COULD STILL SEE SHOWERS
LINGERING OVER THE MTNS INTO EARLY EVENING PER LATEST MODELS.
EXTENDED AVIATION...
POTENTIAL FOR MVFR CIGS/VSBYS ESPECIALLY WEST OF THE BLUE RIDGE
TUE MORNING. A BREAK IN THE CONVECTION OCCURS TUESDAY...THOUGH
CANNOT FULLY RULE OUT ISOLATED SHRA/TSRA IN THE MTNS.
FRONTAL BOUNDARY AND UPPER TROUGH HEAD EAST INTO THE AREA BY
MIDWEEK...WITH GOOD CHANCE OF SHOWERS AND STORMS. THE MAJORITY OF
THE DAYS WILL BE VFR EXCEPT DURING STORMS AND AT NIGHT WITH MVFR
CIGS/VSBY POSSIBLE. FRONT SLOWS DOWN PER LOW PRESSURE/TROPICAL LOW
STRENGTHENING OFF THE COAST OF THE CAROLINAS BY THURSDAY-FRIDAY.
THIS WILL KEEP THE SHRA/TSRA THREAT AT LEAST THURSDAY...THOUGH
FRIDAY COULD BE DRY WITH SUBSIDENCE IF THE OFFSHORE LOW DEEPENS
ENOUGH INTO A TROPICAL CYCLONE. SEE NHC PRODUCTS FOR DETAILS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...WP
NEAR TERM...NF/WP
SHORT TERM...NF
LONG TERM...KK
AVIATION...PC/RAB/WP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
632 AM CDT MON JUN 30 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 420 AM CDT MON JUN 30 2014
AT 4 AM...THE MESOSCALE CONVECTIVE COMPLEX...WHICH BROUGHT THE
HEAVY RAIN TO NORTHEAST IOWA AND SOUTHWEST WISCONSIN AND POSSIBLE
TORNADO NEAR FENNIMORE WISCONSIN...EXTENDED FROM SOUTHERN LAKE
MICHIGAN TO WEST-CENTRAL ILLINOIS. STRONG 850 MB MOISTURE
TRANSPORT AHEAD OF AN 850 MB LOW ACROSS CENTRAL NEBRASKA IS
GENERATING CLUSTERS OF THUNDERSTORMS ACROSS EASTERN NEBRASKA AND
AND NORTHWEST IOWA. SOME ADDITIONAL THUNDERSTORMS ARE STARTING TO
DEVELOP ALONG ALONG A 900 TO 700 MB FRONTOGENETIC BAND ACROSS
SOUTHERN SOUTH DAKOTA. THIS IS IN RESPONSE TO A STRONG SHORTWAVE
TROUGH MOVING THROUGH EASTERN MONTANA AND WYOMING.
FOR THIS MORNING...EXPECT ROUNDS OF SHOWERS AND THUNDERSTORMS TO
DEVELOP ALONG A 900 TO 700 MB BAND OF FRONTOGENESIS ALONG THE
MINNESOTA AND IOWA BORDER. THIS IS STRENGTHENING WILL LIKELY KEEP
THE PRECIPITATION GOING DESPITE THE WEAKENING THAT IS TAKING
PLACE IN THE 925 AND 850 MB MOISTURE TRANSPORT. DEEP MOISTURE
GRADUALLY POOLS ALONG THIS BOUNDARY DURING THE MORNING. ALONG AND
SOUTH OF INTERSTATE 90...WARM CLOUD LAYER DEPTHS CLIMB FROM 3 TO
3.5 KM AT 30.12Z TO AROUND 4 KM AT 30.18Z. DURING THIS SAME TIME
PERIOD...PRECIPITABLE WATER VALUES CLIMB FROM AROUND 1.5 INCHES TO
2.0 INCHES IN THIS SAME AREA. AS A RESULT...THE SHOWERS AND
THUNDERSTORMS WILL BECOME VERY EFFICIENT RAIN PRODUCERS.
IN ADDITION...MEAN LAYER CAPES WILL REMAIN FROM 1500 TO
3500 J/KG. WHILE TYPICALLY THIS INSTABILITY WOULD WANE FROM THE
CONVECTION... SOUTHERLY WINDS WILL CONTINUE TO ADVECT THIS
INSTABILITY FROM AREAS THAT ARE CAPPED TO OUR SOUTH. IN
ADDITION...THE 0-6 KM SHEAR WILL BE FAVORABLE FOR THE DEVELOPMENT
OF ELEVATED SUPERCELLS. WITH A MAJORITY OF THIS SHEAR LOCATED
BELOW 3 KM...THERE WILL BE THE POTENTIAL FOR THESE SUPERCELLS TO
EVOLVED INTO LINES.
FOR THIS AFTERNOON...BOTH THE DETERMINISTIC AND MESO MODELS
SUGGEST THAT CYCLOGENESIS WILL DEVELOP ACROSS NORTHEAST IOWA AND
SOUTHWEST WISCONSIN THIS AFTERNOON. THIS IS RESPONSE TO THE 850 MB
LOW AND STRONG SHORT WAVE TROUGH COMING TOGETHER ACROSS THE AREA.
DUE TO CONVECTIVE FEEDBACK...BOTH THE GFS AND NAM ARE LIKELY TOO
STRONG WITH THEIR CYCLOGENESIS AND THIS GREATLY AFFECTS THEIR WIND
FIELDS. AS RESULT...LOOKED MORE AT THE WIND FIELDS IN THE MESO
MODELS. EVEN THESE MODELS...SHOW A RAPID STRENGTHENING IN THE 925
AND 850 MB MOISTURE TRANSPORT INTO THE REGION. THIS CAUSES THE
PRECIPITABLE WATER VALUES TO CLIMB TO AROUND 2.25 INCHES AND WARM
CLOUD DEPTHS TO INCREASE INTO THE 4 TO 4.5 INCH RANGE. WITH UPWARD
FORCING BEING ENHANCED FURTHER AS THE AREA ENTERS THE RIGHT
ENTRANCE REGION OF A 250 MB...EXPECT THE THREAT FOR HEAVY RAIN TO
CONTINUE.
AS WITH THIS MORNING...THE 0-6 KM SHEAR WILL REMAIN IN THE EXCESS
OF 45 KNOTS THIS AFTERNOON. IN ADDITION THE COMBINATION OF THE
STRONG CAP TO OUR SOUTH AND SOUTHERLY WINDS CONTINUING TO BRING
THIS 2500 TO 3500 J/KG ML CAPES INTO THE AREA WILL PROVIDE AMPLE
INSTABILITY TO KEEP THE THREAT FOR SUPERCELLS GOING DESPITE THE
PERSISTENT CONVECTION ACROSS THE AREA. WITH THE INCREASING WINDS
FIELDS DUE TO THE CYCLOGENESIS...THE 0-1 KM HELICITY AND BULK
SHEAR ALONG WITH LCL HEIGHTS WILL BECOME FAVORABLE FOR THE
POTENTIAL OF TORNADOES ACROSS THE EASTERN PORTIONS OF NORTHEAST
IOWA AND IN SOUTHWEST WISCONSIN DURING THE MID AND LATTER PARTS OF
THE AFTERNOON. THE DUBUQUE RAP HODOGRAPH FOR 29.22Z IS VERY
IMPRESSIVE.
FOR THIS EVENING...THE SEVERE WEATHER AND HEAVY RAIN THREAT WILL
COME QUICKLY TO AN END AS THE SHORT WAVE TROUGH MOVES QUICKLY
THROUGH THE REGION.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 420 AM CDT MON JUN 30 2014
ON TUESDAY...ANOTHER SHORT WAVE TROUGH WILL MOVE THROUGH THE AREA.
UNLIKE TODAY...THERE WILL BE MUCH LESS INSTABILITY /500 TO
1000 J/KG SURFACE CAPES/ AND LESS 0-6 KM SHEAR LESS THAN 35 KNOTS.
AS A RESULT...JUST EXPECTING SHOWERS AND A FEW SCATTERED
THUNDERSTORMS.
ON WEDNESDAY...ANOTHER SHORT WAVE TROUGH MOVES THROUGH THE AREA.
WITH ML CAPES GENERALLY LESS 500 J/KG...MOST OF THE DETERMINISTIC
MODELS HAVE THIS PERIOD DRY. THE LONE EXCEPTION IS THE ECMWF WHICH
GENERATES A FEW SHOWERS. SINCE IT IS SUMMER AND THE ECMWF
TYPICALLY DOES BETTER IN THIS TIME PERIOD...JUST KEPT A SLIGHT
CHANCE OF SHOWERS GOING.
FROM THE FOURTH OF JULY INTO THE UPCOMING WEEKEND...THE MODELS
CONTINUE TO STRUGGLE WITH THEIR TIMING AND LOCATION OF WAVES...SO
JUST STAYED WITH THE MODEL CONSENSUS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 632 AM CDT MON JUN 30 2014
THE MAIN FOCUS IS ON CONVECTIVE TRENDS FOR TODAY AS SHOWERS AND
THUNDERSTORMS MAY MOVE INTO THE TAF SITES BY THIS AFTERNOON.
CONFIDENCE IS NOT HIGH ENOUGH YET TO PUT TSRA INTO THE
FORECAST...BUT THE MAIN PERIOD WHERE IT WILL BE POSSIBLE IS DURING
THE AFTERNOON HOURS. SHOULD SOME TSRA DEVELOP AND HIT THE TAF
SITES...CONDITIONS WILL LIKELY DROP TO IFR FOR A BRIEF PERIOD.
CONDITIONS WILL IMPROVE INTO TONIGHT AS A COLD FRONT MOVES THROUGH
FROM THE WEST.
&&
.HYDROLOGY...
ISSUED AT 420 AM CDT MON JUN 30 2014
WITH DEEP WARM CLOUD DEPTHS...PRECIPITABLE WATER VALUES OF 2 TO
2.25 INCHES...SATURATED SOILS...AND ALREADY HIGH RIVERS AND
STREAM ACROSS NORTHEAST IOWA AND SOUTHEAST MINNESOTA...ISSUED A
FLASH FLOOD WATCH TODAY FOR THE POTENTIAL OF 1 TO 3 INCHES OF
ADDITIONAL RAIN. THERE WILL LIKELY BE LOCALLY HIGHER AMOUNTS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...FLASH FLOOD WATCH THROUGH THIS EVENING FOR WIZ054-055-061.
MN...NONE.
IA...FLASH FLOOD WATCH THROUGH THIS EVENING FOR IAZ008>011-018-019-
029-030.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...HALBACH
HYDROLOGY...BOYNE
AREA FORECAST DISCUSSION
NWS NEW YORK NY
151 PM EDT MON JUN 30 2014
.SYNOPSIS...
THE REGION WILL BE IN BETWEEN THE BERMUDA HIGH AND A SLOWLY
APPROACHING COLD FRONT THROUGH WEDNESDAY NIGHT. THE FRONT WILL
MOVE SLOWLY ACROSS FROM THURSDAY INTO FRIDAY. POTENTIAL LOW
PRESSURE MOVING NORTH ALONG THE EAST COAST SHOULD PASS SOUTH OF
THE REGION FRIDAY INTO FRIDAY NIGHT. HIGH PRESSURE WILL THEN BUILD
IN FOR THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MINOR ADJUSTMENTS MADE FOR THE AFTERNOON. SCT-BKN MID/HIGH LVL
CLOUDS STILL PUSHING ACROSS THE CWA. PCPN WEAKENING NEARING LOWER
HUDSON...BUT WITH SOME INSTABILITY OVER THE INTERIOR
AREAS...CANNOT RULE OUT A STRAY SHRA/TSTM THROUGH THE AFTN. WILL
MAINTAIN 20 POPS FOR THE TIME BEING.
HIGH TEMPS WILL BE NEAR 80 FOR THE COASTAL REGION IN A REPEAT OF
SUNDAYS SEA BREEZE PATTERN. AWAY FROM THE COAST...MID 80S
EXPECTED...THOUGH THIS DEPENDS SOMEWHAT ON THE AMOUNT OF CLOUD
COVER.
THERE IS A MODERATE RISK OF RIP CURRENTS AT ATLANTIC BEACHES TODAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
DEW POINTS CONTINUE A SLOW INCREASE THROUGH THE PERIOD AS
SOUTHERLY FLOW GRADUALLY INCREASES.
HAVE REMOVED THE FOG FROM THE FORECAST FOR TONIGHT. THINKING IS
THAT WE MAY FORM MORE OF A LOW STRATUS CONDITION ALONG THE COAST.
THIS BASED ON LATEST RAP SOUNDINGS AND MOS GUIDANCE. WITH WATER
TEMPS AROUND 70...ADVECTION FOG DOES NOT SEEM LIKELY.
ON TUESDAY...TEMPS CONTINUE TO SLOWLY WARM AND HAVE GONE WITH THE
WARMER GFS MOS.
CONTINUED THE 20-30 POP TO THE NW OF NYC WITH SBCAPE IN THE NAM
NEARING 1000 J/KG.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
ACTIVE WEATHER POSSIBLE LATE IN THE WEEK.
EAST COAST RIDGE GIVES WAY TO APPROACHING TROUGH MID TO LATE WEEK.
SFC HIGH PRESSURE OVER THE ATLANTIC DEPARTS AS THE SLOW MOVING COLD
FRONT APPROACHES THE AREA.
WARM AND HUMID WEATHER IS EXPECTED...WITH MAINLY DIURNALLY DRIVEN
SHOWERS AND THUNDERSTORMS THROUGH WEDNESDAY...WITH HIGHEST POPS
ACROSS THE INTERIOR. THEN POPS INCREASE THURSDAY...THURSDAY NIGHT
AND FRIDAY AS THE FRONT NEARS. PLENTY OF MOISTURE WILL BE TAPPED AS
TROPICAL LOW OFF THE SOUTHEAST COAST LOOKS TO GET PICKED UP BY
SOUTHERLY STEERING WINDS AHEAD OF THE TROUGH.
ECMWF...GFS SEEM TO BE IN REASONABLE AGREEMENT ON THE TRACK OF THE
FRONT...AND TROPICAL LOW. HEAVY RAIN IS POSSIBLE LATER
THURSDAY...THURSDAY NIGHT AND POSSIBLY INTO FRIDAY.
THE TROUGH MOVES ACROSS THE NORTHEAST WITH A RIDGE BUILDING IN
BEHIND FOR A GOOD PORTION OF THE WEEKEND.
WARM TEMPS ARE EXPECTED AS PERSISTENT SOUTHERLY FLOW PREVAILS. ABOVE
NORMAL READINGS CAN BE EXPECTED TUESDAY NIGHT THROUGH WEDNESDAY
NIGHT...WITH CLOSER TO NORMAL READINGS THEREAFTER. HOTTEST DAY THIS
TIME FRAME APPEARS TO BE WEDNESDAY WITH READINGS IN THE 80S TO
AROUND 90.
INCREASING CLOUDS AND HIGHER COVERAGE OF SHOWERS/TSTMS THURSDAY AND
FRIDAY WILL KNOCK A FEW DEGREES OFF DAYTIME TEMPS. PLENTY OF
SUNSHINE OVER THE WEEKEND SHOULD RESULT IN NEAR NORMAL READINGS BEHIND
THE LOW/FRONT.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
HIGH PRESSURE OFF THE MID ATLANTIC COAST WILL SLOWLY DRIFT
EASTWARD.
VFR THROUGH MUCH OF THE PERIOD.
AFTERNOON SEA BREEZES WILL INCREASE WINDS TO 10 TO 15 KT AT THE
COASTAL TERMINALS. A FEW OCCASIONAL GUSTS CLOSE TO 20 KT ARE
POSSIBLE FROM LATE DAY UNTIL AT LEAST SUNSET AT COASTAL TERMINALS.
WINDS DIMINISH TONIGHT.
EXPECT ANOTHER NIGHT OF STRATUS AND/OR FOG FOR EASTERN TERMINALS.
NOT SURE JUST HOW WIDESPREAD IT WILL BE. GENERALLY LOOKING AT LOW-
END MVFR OR IFR CONDITIONS LATE TONIGHT.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS
CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: OCCASIONAL GUSTS POSSIBLE THIS AFTERNOON
INTO THE UPPER TEENS AND LOWER 20 KT RANGE.
KLGA FCSTER COMMENTS: OCCASIONAL GUSTS POSSIBLE THIS AFTERNOON
INTO THE UPPER TEENS AND LOWER 20 KT RANGE.
KEWR FCSTER COMMENTS: OCCASIONAL GUSTS POSSIBLE THIS AFTERNOON
INTO THE UPPER TEENS AND LOWER 20 KT RANGE.
KTEB FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.
KHPN FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.
KISP FCSTER COMMENTS: OCCASIONAL GUSTS POSSIBLE THIS AFTERNOON
INTO THE UPPER TEENS AND LOWER 20 KT RANGE.
.OUTLOOK FOR 12Z TUE THROUGH FRI...
.TUE...CHANCE OF AN AFTERNOON TSTM WITH BRIEF MVFR OR LOWER CONDS
AND/OR AND GUSTY WINDS AT KSWF. FOG AND LOW STRATUS WITH MVFR OR
LOWER CONDS LIKELY LATE AT NIGHT.
.WED...FOG AND LOW STRATUS WITH MVFR OR LOWER CONDS BURNING OFF
EARLY IN THE MORNING. CHANCE OF SHOWERS/TSTMS WITH MVFR OR LOWER
CONDS IN THE AFTERNOON MAINLY FROM NYC METRO NORTH AND
WEST...SPREADING TO THE COAST IN THE EVENING. RAIN MAY BE HEAVY AT
TIMES.
.THU-FRI...NUMEROUS SHOWERS/TSTMS...WITH IFR CONDS IN HEAVY
RAIN POSSIBLE.
.SATURDAY...VFR.
&&
.MARINE...
WINDS AND WAVES FORECAST ON TRACK FOR TODAY.
SEA BREEZES AGAIN LATE THIS AFTN WILL RESULT IN A PERIOD OF 15 KT
WITH GUST UP TO 20 KT ON THE WATERS. HIGHEST WOULD BE IN SOUTH OF
THE ROCKAWAYS.
SEA BREEZES ARE STRONGER YET TUESDAY AFTN WITH GUSTS UP TO 25 KT
AND THE POTENTIAL FOR SCA CONDITIONS...ESPECIALLY ON THE OCEAN.
PERSISTENT SOUTHERLY FLOW TUESDAY NIGHT WILL DIMINISH WEDNESDAY AND
THURSDAY AS A COLD FRONT APPROACHES AND THE PRESSURE GRADIENT
WEAKENS. WITH THE FRONT SLOWLY MOVING ACROSS THE WATERS EARLY
FRIDAY...WINDS REMAIN RATHER LIGHT. NEED TO MONITOR EVENTUAL
PROGRESSION OF A TROPICAL LOW LATE FRIDAY AS IT POSSIBLY APPROACHES
THE WATERS FROM THE SOUTH.
OCEAN SEAS OF 3 TO 6 FEET TUESDAY NIGHT WILL SUBSIDE AS THE
SOUTHERLY WINDS DIMINISH WEDNESDAY THROUGH THURSDAY. AT THIS
TIME...SEAS SHOULD REMAIN BELOW 5 FT MOST OF FRIDAY...BUT WOULD
LIKELY BUILD LATE IN THE DAY DEPENDING ON TRACK AND STRENGTH OF LOW
PRESSURE TO THE SOUTH.
&&
.HYDROLOGY...
NO SIGNIFICANT PRECIPITATION IS EXPECTED INTO TUESDAY.
THERE IS THE POTENTIAL FOR SIGNIFICANT RAINFALL TOWARD THE END OF
THE WEEK...THURSDAY AND THURSDAY NIGHT. AT THIS TIME THERE IS TOO
MUCH UNCERTAINTY TO SPECIFY EXACT AMOUNTS OR SPECIFIC THREATS.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TONGUE/PW
NEAR TERM...SEARS/TONGUE
SHORT TERM...TONGUE
LONG TERM...PW
AVIATION...BC
MARINE...TONGUE/PW
HYDROLOGY...TONGUE/PW
EQUIPMENT...
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
150 PM EDT MON JUN 30 2014
.PREV DISCUSSION...
UPDATE...
/ISSUED 1112 AM EDT MON JUN 30 2014/
RAIN CONTINUES ACROSS THE NORTHERN PORTION OF THE STATE WITH
LIMITED LIGHTNING ACTIVITY. HRRR HAS BEEN HANDLING THIS ACTIVITY
THE BEST IN TERMS OF LOCATION AND THUS NEAR TERM FORECAST UPDATES
WERE TO TREND THE POPS TOWARDS THE HRRR. HAVE INCREASED
SIGNIFICANTLY THE POPS ACROSS NORTH GEORGIA THROUGHOUT THE MORNING
AND INTO THE AFTERNOON. ALSO HAVE INCREASED POPS 10-20 PERCENT
ACROSS MANY AREAS IN CENTRAL GA.
HEAVY RAIN REMAINS THE MAIN CONCERN ESPECIALLY ACROSS NORTH
GEORGIA WITH MULTIPLE ROUNDS OF RAIN OVER A FEW DAYS AND LONG
PERIODS OF RAIN THIS MORNING. STILL AGREE WITH THE POTENTIAL OF
STRONG TO A FEW SEVERE STORMS TODAY.
SHORT TERM /TODAY THROUGH TUESDAY/...
/ISSUED 339 PM EDT MON JUN 30 2014/
LINE OF WEAKENING CONVECTION ASSOCIATED WITH A MODERATE SHORT
WAVE RIDING OVER THE TOP OF THE WEAK UPPER RIDGE IS EXPECTED TO
CONTINUE WEAKENING AS IT SWEEPS ACROSS NORTH GEORGIA THROUGH THE
EARLY MORNING HOURS. THE SYNOPTIC SETUP TODAY REMAINS VERY SIMILAR
TO YESTERDAY WITH GEORGIA ON THE PERIPHERY OF THE WEAK UPPER RIDGE
AND A MODERATE SHORT WAVE RIDING OVER THE TOP ACROSS NORTH AND
EAST GEORGIA. I HAVE CONCENTRATED MY BETTER POPS ACROSS THAT AREA
THIS AFTERNOON BUT HAVE KEPT THE PERCENTAGES LIMITED TO THE MID TO
HIGH CHANCE RANGE FOR NOW. HAD A FEW STORMS REACH THE STRONG TO
MARGINALLY SEVERE LEVEL YESTERDAY AND CANNOT RULE OUT THE SAME
THIS AFTERNOON INTO THE EARLY EVENING...HOWEVER I DO NOT EXPECT
WIDESPREAD SEVERE THUNDERSTORMS. AMPLE PRECIP WATER WILL MAKE
HEAVY RAIN/MINOR FLOODING A POSSIBILITY AGAIN AS WELL. MODELS
CONTINUE TO SHOW THE SLOW...GRADUAL WEAKENING OF THE UPPER RIDGE
INTO TUESDAY... HOWEVER ALL ARE SHOWING A LACK OF THE MID/UPPER-
LEVEL SHORT WAVE FORCING THAT WE SAW YESTERDAY AND ANTICIPATE
TODAY...SO I HAVE GONE WITH A GENERAL LESSENING IN CONVECTIVE
COVERAGE.
OVERNIGHT LOW TEMPERATURES ARE EXPECTED TO REMAIN NEAR SEASONAL
NORMALS...WITH AFTERNOON HIGHS REACHING A FEW DEGREES ABOVE IN MOST
AREAS OUTSIDE OF ANYONE WHO GETS SOME EARLY PRECIPITATION. HEAT
INDEX VALUES ARE FORECAST TO REMAIN BELOW ADVISORY LEVELS...BUT ARE
LIKELY TO APPROACH 100-102 ACROSS OUR CENTRAL GEORGIA COUNTIES TODAY
AND TUESDAY. AMOUNT OF CLOUD COVER AND CONVECTIVE COVERAGE WILL HAVE
A NOTICEABLE IMPACT ON WHICH AREAS PUSH THE 100 DEGREE HEAT INDEX
LINE EACH AFTERNOON AND BOTH ARE EXPECTED TO BE SOMEWHAT VARIABLE
TODAY BUT LESS ON TUESDAY.
20
LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
/ISSUED 339 PM EDT MON JUN 30 2014/
LONG RANGE MODELS CONTINUE TO SHOW HIGH PRESSURE WEAKENING ITS
GRIP TUESDAY NIGHT AND WEDNESDAY AS A LONG WAVE TROUGH DEEPENS
ACROSS THE MS VALLEY REGION. THIS SYSTEM PUSHES A COLD FRONT INTO
THE OHIO AND UPPER TN VALLEY REGIONS BY WEDNESDAY NIGHT. AT THIS
SAME TIME... THE GFS AND ECMWF ARE SHOWING A LOW PRESSURE SYSTEM
ALONG THE EAST CENTRAL FLORIDA COAST TUESDAY NIGHT... AND DRIFTING
IT NORTHWARD TO JUST OFF THE GEORGIA COAST ON WEDNESDAY AND
WEDNESDAY NIGHT. MODELS SHOW FAIRLY GOOD AGREEMENT WITH THE LONG
WAVE TROUGH PUSHING EASTWARD AND PUSHING A COLD FRONT INTO THE
LOWER TN VALLEY ON THURSDAY... WHILE IT ALSO SERVES TO LIFT THE
LOW PRESSURE SYSTEM NORTHEASTWARD AND ALONG THE SOUTH AND NORTH
CAROLINA COASTS ON THURSDAY AND THURSDAY NIGHT. BY FRIDAY... BOTH
MODELS SHOW THE FRONT PUSHING INTO SOUTH GA WITH DRY HIGH PRESSURE
BUILDING IN OVER THE FORECAST AREA BY FRIDAY AFTERNOON. AT THIS
SAME TIME... THE SURFACE LOW OFF THE CAROLINAS LIFTS NORTHEASTWARD
AND TRACKS ALONG THE EAST CENTRAL AND NORTHEAST ATLANTIC COASTAL
AREAS THROUGH SATURDAY...THEN DRIFTING FURTHER OUT TO SEA SATURDAY
NIGHT AND SUNDAY. THIS LOW PRESSURE SYSTEM WILL HAVE TO BE
MONITORED CLOSELY FOR POTENTIAL TROPICAL DEVELOPMENT WITHIN THE
NEXT 3 TO 5 DAYS.
THE APPROACHING COLD FRONT AND POSITION OF THE SURFACE LOW OFF
THE GA COASTS ON WEDNESDAY...THEN ALONG THE CAROLINAS ON THURSDAY
WILL WARRANT A CHANCE POPS FOR MOST AREAS ON WEDNESDAY AND THURSDAY.
THEN AS THE COLD FRONT PUSHES SOUTH ON FRIDAY... EXPECT ADDED HIGH
PRESSURE SUBSIDENCE AND DRY AIR TO HOLD POPS DOWN TO ISOLATED
NORTH AND MAYBE LOW SCATTERED CENTRAL FOR FRIDAY AND SATURDAY...
AND POSSIBLY INTO SUNDAY. AS A RESULT... EXPECTING A NICE QUIET
WEATHER PATTERN FOR THE 4TH OF JULY WEEKEND.
AS FOR TEMPS... HAVE LEANED CLOSE TO A MEX/HPC BLEND FOR THROUGH
THE EXTENDED PERIOD...WITH COOLER HIGHS EXPECTED TO FILTER IN OVER
THE AREA FOR FRIDAY AND SATURDAY BEHIND THE FRONT. 39
&&
.AVIATION...
18Z UPDATE...
MAIN AREA OF THUNDERSTORMS HAS PASSED THROUGH ATL TAF SITES AND
SHOULD SEE IMPROVEMENT OF CONDITIONS. WITH DEVELOPMENT TO THE NW
OF THE SITES THOUGH...LEAVING IN TEMPO FOR TS FOR THE NEXT FEW
HOURS. WINDS SHOULD ALSO SUBSIDE OVER THE NEXT HOUR...UNLESS ATL
AREA IS AFFECTED BY ANOTHER THUNDERSTORM. POTENTIAL FOR FOG
DEVELOPMENT IN THE MORNING...MAINLY AHN AND MCN. CHANCES ARE TOO
LOW TO MENTION TSRA OR SHRA FOR TUESDAY AFTERNOON.
//ATL CONFIDENCE...18Z UPDATE...
MEDIUM CONFIDENCE ON WIND DIRECTION...CIGS AND VSBYS. LOW
CONFIDENCE ON TSRA.
11
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 91 70 93 73 / 80 30 20 10
ATLANTA 89 72 92 76 / 60 20 20 10
BLAIRSVILLE 84 65 88 69 / 100 20 20 10
CARTERSVILLE 89 68 92 71 / 60 10 20 10
COLUMBUS 93 74 94 76 / 50 40 20 10
GAINESVILLE 88 70 91 74 / 90 20 20 10
MACON 93 70 94 73 / 50 40 20 10
ROME 90 69 92 72 / 70 10 20 10
PEACHTREE CITY 90 67 92 70 / 60 20 20 10
VIDALIA 93 73 94 74 / 50 40 30 10
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...11
LONG TERM....DEESE
AVIATION...11
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
528 PM CDT MON JUN 30 2014
.MESOSCALE DISCUSSION...
THE CURRENT FOCUS IS WITH THE AREA OF STRONG CONVECTION JUST WEST OF
BUREAU COUNTY. THE LATEST RADAR IMAGERY INDICATES A REAR INFLOW JET
TRYING TO DEVELOP...WHICH COULD FAVOR THIS STORM TO TRANSITION INTO
ANOTHER FORWARD PROPAGATING BOWING SEGMENT WITHIN THE HALF HOUR. IF
THIS DOES OCCUR...THIS BOWING SEGMENT WOULD LIKELY SHIFT EAST-
NORTHEASTWARD ACROSS THE I-80 TO I-88 CORRIDORS OVER THE NEXT
COUPLE HOURS...POSSIBLY IMPACTING THE CHICAGO AREA AROUND 7 PM. WE
WILL BE MONITORING THIS CLOSELY.
THE OTHER CONCERN IS FOR FLASH FLOODING ACROSS THE AREA. CONVECTIVE
ACTIVITY IS BEGINNING TO LINE UP WEST TO EAST ACROSS WESTERN
ILLINOIS...AND OBJECTIVE SURFACE ANALYSIS SUGGESTS THAT THIS AREA
IS ALONG THE GRADIENT OF A STRONGLY UNSTABLE ATMOSPHERE...WITH
AROUND 5000 J/KG MLCAPE AND 2 INCH PWATS...AS INDICATED FROM
LATEST RAP MESOANALYSIS. WITH STRONG LOW LEVEL MOISTURE CONTINUING
TO STREAM INTO THIS AREA VIA STOUT SOUTHERLY WINDS...CONTINUED
REGENERATION OF STORMS IS LIKELY ACROSS WESTERN ILLINOIS...AND
THESE STORMS WILL MOVE EAST...SETTING UP TRAINING STORMS. THIS
ACTIVITY INCREASES THE THREAT OF FLASH FLOODING ACROSS NORTHERN
ILLINOIS...AND AS SUCH...WE HAVE EXPANDED THE FLASH FLOOD MUCH FOR
MUCH OF THE AREA THROUGH TONIGHT.
KJB
&&
.DISCUSSION...
117 PM CDT
THIS EVENING/OVERNIGHT...
MAIN CONCERN FOR THIS EVENING THROUGH MIDNIGHT WILL BE ON SEVERE
WEATHER TIMING/COVERAGE/INTENSITY. THE SPC HAS EXPANDED THE ENTIRE
FORECAST AREA INTO THE MODERATE RISK FOR SEVERE WEATHER TODAY...WITH
THE FOCUS BEING ON DAMAGING WINDS IN EXCESS OF 70MPH AND LARGE HAIL.
GIVEN THE HIGH DEW POINTS...AND PWAT VALUES ARND 1.5 TO
1.75"...WHATEVER CONVECTION OCCURS COULD BE VERY EFFICIENT AT
PRODUCING TORRENTIAL DOWNPOURS AND AS SUCH WOULD INTRODUCE A
FLOODING CONCERN DESPITE STORMS FORWARD PROPAGATION. WHILE THE
PROBABILITY IS NOT ZERO FOR AN ISOLATED TORNADO...THE GREATEST FOCUS
FOR THIS WILL BE WELL WEST OF THE FORECAST AREA IN IOWA. IF WINDS
CAN BACK TO THE SOUTHEAST HOWEVER...THIS WOULD INTRODUCE INCREASED
HELICITY TO THE AREA.
THE FOCAL POINT FOR CONVECTION HAS BEEN ON THE ACTIVITY PRESENTLY
ONGOING IN EASTERN NEBRASKA/WESTERN IOWA. VISIBLE IMAGERY HAS A
BOUNDARY DEPICTED ACROSS SOUTHWEST IOWA STRETCHING EAST TO JUST
SOUTH OF MOLINE THEN TURNING SOUTHEAST ACROSS SOUTHCENTRAL IL TO
JUST SOUTH OF TERRE HAUTE IN. ALONG AND SOUTH OF THIS BOUNDARY DEW
PTS ARE GENERALLY IN THE LOW/MID 70S...WHILE TO THE NORTH DEW POINTS
ARE IN THE UPR 60S. THE EXCEPTION IS OVER THE SOUTHERN CWFA WHERE
DEW POINTS HAVE BEEN ABLE TO BUMP BACK INTO THE LOW 70S WITH A
SOUTHERLY WIND. THE WINDS ARE BACKED TO THE SOUTHEAST/EAST EARLY
THIS AFTN OVER SOUTHCENTRAL IOWA...AND WITH THE CIRRUS SHIELD
BEGINNING TO THIN OVER EASTERN IOWA EARLY THIS AFTN...THE ATMOSPHERE
SHUD ONLY FURTHER DESTABILIZE.
HI-RES GUIDANCE CONTINUES TO FOCUS A LINE SEGMENT PUSHING INTO
EASTERN IOWA BY 20-22Z...THEN THERE IS SOME SLIGHT DIFFERENCES ON
HOW THIS FEATURE ARRIVES ACROSS NORTHERN IL/NORTHWEST IN ALONG WITH
TIMING. NONETHELESS...GIVEN THE AFOREMENTIONED BUOYANT ATMOSPHERE
AND UNIDIRECTIONAL MEAN LAYER FLOW...IT DOES SUPPORT THIS LINE OF
CONVECTION THAT ARRIVES ACROSS FAR WESTERN/NORTHWESTERN IL TO MORPH
INTO A BOWING SEGMENT AND POSSIBLY TRANSITION INTO A DERECHO TYPE
EVENT...WHICH WOULD LIKELY BEGIN TO TURN SOUTHEAST ACROSS THE
FORECAST AREA THIS EVENING.
ACTIVITY LEVEL SHOULD QUICKLY LEVEL OFF LATER THIS EVENING...WITH
THE TIMING TO HAVE PUSHED THRU THE CWFA BEFORE MIDNIGHT. THEN THE
DRY SLOT ARRIVES...HOWEVER HAVE OPTED TO HOLD ONTO SOME LINGERING
SHRA/TSRA OVERNIGHT. CONFIDENCE IS RATHER LOW THAT ANY ACTIVITY WILL
BE REMAINING...SO THIS MAY BE ABLE TO BE REMOVED LATER THIS EVENING
AND GO WTIH A DRY OVERNIGHT.
TUESDAY THROUGH THURSDAY...
LEADING VORT WILL PIVOT EAST OF THE REGION EARLY TUE...WITH THE DRY
SLOT STILL BEING PROGGED TO KEEP DRY CONDS OVER THE FORECAST AREA
THRU THE BULK OF THE DAY TUE. BY MID/LATE AFTN THE MID-LVL TROUGH
AXIS APPROACHES FROM THE NORTHWEST...AND WITH ANY SFC
DESTABILIZATION...A FEW ISO TSRA COULD DEVELOP FROM THE STEEP LAPSE
RATES AND COOLING IN THE MID-LVLS. WITH THE FLOW REMAINING
PROGRESSIVE...THE TROUGH AXIS SLIDES OVERHEAD BY 03Z WED AND SHUD
BRING A QUICK END TO ANY DIURNALLY DRIVEN SHRA/TSRA ACROSS THE CWFA
WITH A DRY OVERNIGHT PERIOD. GUIDANCE IS ALSO INDICATING A TRAILING
WEAK TROUGH SLIDING INTO THE CENTRAL PLAINS WED MORNING...WITH AN
ABUNDANCE OF LOW/MID LVL MOISTURE WRAPPING AROUND THE WESTERN GREAT
LAKES REGION. THIS WILL LIKELY BRING A CHC FOR LIGHT SHOWERS FOR
WED. WITH CONSIDERABLE SOLAR SHIELDING WED...AND A THERMAL TROUGH OF
6 TO 8 DEG C OVERHEAD...TEMPS COULD STRUGGLE TO WARM BEYOND 70-74
FOR NORTHERN IL/NORTHWEST IN. IT IS PLAUSIBLE THAT A FEW POINTS IN
FAR NORTHERN IL THAT REMAIN IN THE UPR 60S WED AFTN.
BROAD TROUGH THEN PUSHES EAST WED NGT...WITH SFC ANTI-CYCLONIC
FEATURE BUILDING IN FROM THE WEST. THIS FEATURE WILL HELP TO DRY THE
LOW-LEVELS OUT AND ALLOW WINDS TO TURN NORTHWEST TO NORTH. THEN FOR
THUR THE NORHTERLY DRY FLOW WILL BRING SUNNY SKIES WITH TEMPS
GENERALLY IN THE 70S. A LAKE BREEZE LOOKS LIKELY AND COULD KEEP ON
ONSHORE FLOW FOR THE ADJACENT LAKESHORE COMMUNITIIES AND TEMPS IN
THE 60S.
CONFIDENCE...HIGH.
FRIDAY THROUGH MONDAY...
ENSEMBLES CONTINUE TO PROG A RIDGE ACROSS THE CANADIAN ROCKIES FOR
THE END OF THE WORK WEEK...ALLOWING A DOWNSTREAM TROUGH TO BE OVER
THE GREAT LAKES/NORTHEAST CONUS. AS THE WEEKEND PROGRESSES THE WAVE
WILL BEGIN TO RELAX...ALTHOUGH THE MID-LVL TROUGH WILL DRIFT EAST BY
SAT/SUN OVER THE UPPER MIDWEST/NORTH OF LAKE SUPERIOR. THIS SHUD
ALLOW TEMPS TO SLOWLY RETURN TO NEAR SEASONAL CONDS. ALTHOUGH AS THE
WEEKEND PROGRESSES...THE LONGWAVE PATTERN DOES TRANSITION INTO A
SEMI-ZONAL FLOW WITH HEIGHTS STEADILY INCREASING ACROSS THE ENTIRE
CONUS. TEMPS FOR FRI SHUD CONTINUE TO BE SUB-SEASONAL IN THE 70S
NEAR 80...THEN BACK TO ARND 80 OR LOW 80S FOR THE WEEKEND. EARLY
NEXT WEEK THE PATTERN DOES APPEAR TO POINT TOWARDS TEMPS RETURNING
TO LOW/MID 80S. IN ADDITION TO THE SEMI-ZONAL FLOW...IT DOES SUPPORT
A QUICK WEST-EAST FLOW OF WEAK WAVES. THIS COULD EASILY BRING A LOW
CHC POPS FOR THE WEEKEND/EARLY NEXT WEEK.
CONFIDENCE...HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 22Z...
* LINE OF THUNDERSTORMS APPROACHING TERMINALS. ETA 2330 AT ORD AND
2345 AT MDW.
* POTENTIAL FOR WINDS TO GUST UP TO 50 KT WITH LEADING EDGE OF THE
LINE.
* POSSIBLE BRIEF IFR VSBYS UNDER HEAVIEST THUNDERSTORM. POOREST
CONDITIONS LAST 20-30 MINUTES. RAIN AND OCCASIONAL THUNDER FOR
ANOTHER 2 HOURS AFTER THAT.
* GREATLY DISTURBED WIND FIELD FOLLOWING THE INITIAL LINE OF
STORMS.
* SOUTHWEST WINDS REESTABLISH THEMSELVES AROUND 03Z.
ED F
//DISCUSSION...UPDATED 18Z...
RELATIVELY QUIET CONDITIONS TO START THE FORECAST PERIOD WITH
SOUTHWEST WINDS AND ONLY HIGH LEVEL CIRRUS IN PLACE. THIS WILL
LIKELY CHANGE LATER THIS AFTERNOON AND EVENING AS A COMPLEX OF
THUNDERSTORMS CURRENTLY OVER IOWA TRACKS EAST TOWARDS THE
TERMINALS. CURRENTLY MONITORING THUNDERSTORMS OVER CENTRAL IOWA
WHICH WILL EITHER BE THE THUNDERSTORMS TO MOVE THROUGH THE
TERMINALS LATER TODAY OR WILL AT LEAST BE ASSOCIATED WITH THE
EXPECTED THUNDERSTORMS. HIGH CONFIDENCE DOES EXIST WITH THE
POTENTIAL FOR THUNDERSTORMS OVER THE TERMINALS LATE THIS AFTERNOON
INTO THE EVENING...BUT THERE DOES REMAIN SOME UNCERTAINTY WITH
EXACT TIMING. IF THE SYSTEM BECOMES MORE ORGANIZED OVER THE NEXT
ONE TO TWO HOURS...IT WOULD THEN QUICKLY TRACK EAST TOWARDS THE
TERMINALS AND POSSIBLY REACH THEM BEFORE THE TAF TIMES OF AROUND
23Z. IF NOT...THE CURRENT TIME...IF NOT LATER...WOULD BE A MORE
PREFERRED TIMING. WILL CONTINUE TO CLOSELY MONITOR TRENDS AND
ADJUST TIMES AS NECESSARY. THESE STORMS DO HAVE THE POTENTIAL TO
BE SEVERE...WITH HIGH WIND GUSTS IN EXCESS OF 70 MPH POSSIBLE. NOT
ONLY IS LOWER VIS LIKELY WITH THESE THUNDERSTORMS...BUT MVFR CIGS
ARE A DEFINITE POSSIBILITY AS WELL. DEPARTING COMPLEX LATER THIS
EVENING WILL RESULT IN LINGERING VFR CIGS TONIGHT...WITH A HIGHLY
ERRATIC WIND FIELD LIKELY. DID NOT CONVEY THE POSSIBLE WIND FIELD
ON THE BACKSIDE OF THE THUNDERSTORMS AND WILL LIKELY ADD THIS
LATER...BUT WITH SOME TEMPORARY EASTERLY COMPONENT POSSIBLE BEFORE
THEY SHIFT BACK TO THE SOUTHWEST.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 22Z...
* MEDIUM TO HIGH CONFIDENCE WITH WIND TRENDS DURING FORECAST
PERIOD... EXCEPT LOW CONFIDENCE OF WIND FORECAST FOR 1-2 HOURS
AFTER THUNDERSTORMS.
* HIGH FOR TSRA LATE AFTERNOON THROUGH MID EVENING...MEDIUM ON
TIMING.
ED F
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
* TUESDAY NIGHT...DRY/VFR.
* WEDNESDAY...CHANCE OF SHRA.
* THURSDAY THROUGH SATURDAY...DRY/VFR.
* SUNDAY...SLIGHT CHANCE OF TSRA.
&&
.MARINE...
303 PM CDT
PRIMARY MARINE CONCERN IS OVER THE NEARSHORE WATERS AND SOUTH HALF
THIS EVENING AS AN INTENSE COMPLEX OF THUNDERSTORMS LIKELY HOLDS
TOGETHER AND BRINGS A PERIOD OF DANGEROUSLY STRONG WINDS AND
FREQUENT LIGHTNING. HAVE LEFT THE DENSE FOG ADVISORY FOR THE NORTH
HALF UNTIL THIS EVENING. BEFORE CLOUDS MOVED OVERHEAD...VISIBLE
SATELLITE SHOWED A BANK OF FOG COVERING MUCH OF THE NORTHERN PART
OF THE LAKE. SYNOPTIC SOUTHERLY WINDS STILL MAY BECOME STRONG
ENOUGH FOR SMALL CRAFT CRITERIA THIS EVENING IN THE NEARSHORE BUT
DO NOT HAVE ENOUGH CONFIDENCE TO HOIST AN ADVISORY.
HAVE BETTER CONFIDENCE IN SMALL CRAFT WIND CRITERIA BEING MET ON
TUESDAY. TIGHT PRESSURE GRADIENT AND DEEP MIXING FROM LAND WILL
LIKELY RESULT IN WEST-SOUTHWEST WINDS AROUND 20 KT AND FREQUENT
GUSTS TO 25 KT OR EVEN A BIT HIGHER LATE TUESDAY MORNING THROUGH
LATE TUESDAY AFTERNOON. HAVE SOME CONCERN THAT GUSTY WINDS MAY
EXTEND A BIT INTO TUESDAY EVENING. HIGH PRESSURE WILL SPREAD OVER
THE LAKE THURSDAY INTO FRIDAY AND ONLY SLOWLY MOVE EASTWARD ON
SATURDAY. AN FAIRLY EXTENDED PERIOD OF LIGHT WINDS WITH DIRECTIONS
NEAR THE SHORES CONTROLLED BY LAKE BREEZE INFLUENCES BY DAY WILL
ENSUE WEDNESDAY NIGHT THROUGH AT LEAST FRIDAY NIGHT. MODEST
SOUTHERLY WINDS WILL DEVELOP ON SATURDAY AS THE HIGH SLIDES EAST.
RC
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032 UNTIL 4 AM TUESDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002 UNTIL 4 AM TUESDAY.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ868 UNTIL 9 PM MONDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-
LMZ745...9 AM TUESDAY TO 7 PM TUESDAY.
&&
$$
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WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
525 PM CDT MON JUN 30 2014
.MESOSCALE DISCUSSION...521 PM
THE CURRENT FOCUS IS WITH THE AREA OF STRONG CONVECTION JUST WEST OF
BUREAU COUNTY. THE LATEST RADAR IMAGERY INDICATES A REAR INFLOW JET
TRYING TO DEVELOP...WHICH COULD FAVOR THIS STORM TO TRANSITION INTO
ANOTHER FORWARD PROPAGATING BOWING SEGMENT WITHIN THE HALF HOUR. IF
THIS DOES OCCUR...THIS BOWING SEGMENT WOULD LIKELY SHIFT EAST-
NORTHEASTWARD ACROSS THE I-80 TO I-88 CORRIDORS OVER THE NEXT
COUPLE HOURS...POSSIBLY IMPACTING THE CHICAGO AREA AROUND 7 PM. WE
WILL BE MONITORING THIS CLOSELY.
THE OTHER CONCERN IS FOR FLASH FLOODING ACROSS THE AREA. CONVECTIVE
ACTIVITY IS BEGINNING TO LINE UP WEST TO EAST ACROSS WESTERN
ILLINOIS...AND OBJECTIVE SURFACE ANALYSIS SUGGESTS THAT THIS AREA
IS ALONG THE GRADIENT OF A STRONGLY UNSTABLE ATMOSPHERE...WITH
AROUND 5000 J/KG MLCAPE AND 2 INCH PWATS...AS INDICATED FROM
LATEST RAP MESOANALYSIS. WITH STRONG LOW LEVEL MOISTURE CONTINUING
TO STREAM INTO THIS AREA VIA STOUT SOUTHERLY WINDS...CONTINUED
REGENERATION OF STORMS IS LIKELY ACROSS WESTERN ILLINOIS...AND
THESE STORMS WILL MOVE EAST...SETTING UP TRAINING STORMS. THIS
ACTIVITY INCREASES THE THREAT OF FLASH FLOODING ACROSS NORTHERN
ILLINOIS...AND AS SUCH...WE HAVE EXPANDED THE FLASH FLOOD MUCH FOR
MUCH OF THE AREA THROUGH TONIGHT.
KJB
&&
.DISCUSSION...
117 PM CDT
THIS EVENING/OVERNIGHT...
MAIN CONCERN FOR THIS EVENING THROUGH MIDNIGHT WILL BE ON SEVERE
WEATHER TIMING/COVERAGE/INTENSITY. THE SPC HAS EXPANDED THE ENTIRE
FORECAST AREA INTO THE MODERATE RISK FOR SEVERE WEATHER TODAY...WITH
THE FOCUS BEING ON DAMAGING WINDS IN EXCESS OF 70MPH AND LARGE HAIL.
GIVEN THE HIGH DEW POINTS...AND PWAT VALUES ARND 1.5 TO
1.75"...WHATEVER CONVECTION OCCURS COULD BE VERY EFFICIENT AT
PRODUCING TORRENTIAL DOWNPOURS AND AS SUCH WOULD INTRODUCE A
FLOODING CONCERN DESPITE STORMS FORWARD PROPAGATION. WHILE THE
PROBABILITY IS NOT ZERO FOR AN ISOLATED TORNADO...THE GREATEST FOCUS
FOR THIS WILL BE WELL WEST OF THE FORECAST AREA IN IOWA. IF WINDS
CAN BACK TO THE SOUTHEAST HOWEVER...THIS WOULD INTRODUCE INCREASED
HELICITY TO THE AREA.
THE FOCAL POINT FOR CONVECTION HAS BEEN ON THE ACTIVITY PRESENTLY
ONGOING IN EASTERN NEBRASKA/WESTERN IOWA. VISIBLE IMAGERY HAS A
BOUNDARY DEPICTED ACROSS SOUTHWEST IOWA STRETCHING EAST TO JUST
SOUTH OF MOLINE THEN TURNING SOUTHEAST ACROSS SOUTHCENTRAL IL TO
JUST SOUTH OF TERRE HAUTE IN. ALONG AND SOUTH OF THIS BOUNDARY DEW
PTS ARE GENERALLY IN THE LOW/MID 70S...WHILE TO THE NORTH DEW POINTS
ARE IN THE UPR 60S. THE EXCEPTION IS OVER THE SOUTHERN CWFA WHERE
DEW POINTS HAVE BEEN ABLE TO BUMP BACK INTO THE LOW 70S WITH A
SOUTHERLY WIND. THE WINDS ARE BACKED TO THE SOUTHEAST/EAST EARLY
THIS AFTN OVER SOUTHCENTRAL IOWA...AND WITH THE CIRRUS SHIELD
BEGINNING TO THIN OVER EASTERN IOWA EARLY THIS AFTN...THE ATMOSPHERE
SHUD ONLY FURTHER DESTABILIZE.
HI-RES GUIDANCE CONTINUES TO FOCUS A LINE SEGMENT PUSHING INTO
EASTERN IOWA BY 20-22Z...THEN THERE IS SOME SLIGHT DIFFERENCES ON
HOW THIS FEATURE ARRIVES ACROSS NORTHERN IL/NORTHWEST IN ALONG WITH
TIMING. NONETHELESS...GIVEN THE AFOREMENTIONED BUOYANT ATMOSPHERE
AND UNIDIRECTIONAL MEAN LAYER FLOW...IT DOES SUPPORT THIS LINE OF
CONVECTION THAT ARRIVES ACROSS FAR WESTERN/NORTHWESTERN IL TO MORPH
INTO A BOWING SEGMENT AND POSSIBLY TRANSITION INTO A DERECHO TYPE
EVENT...WHICH WOULD LIKELY BEGIN TO TURN SOUTHEAST ACROSS THE
FORECAST AREA THIS EVENING.
ACTIVITY LEVEL SHOULD QUICKLY LEVEL OFF LATER THIS EVENING...WITH
THE TIMING TO HAVE PUSHED THRU THE CWFA BEFORE MIDNIGHT. THEN THE
DRY SLOT ARRIVES...HOWEVER HAVE OPTED TO HOLD ONTO SOME LINGERING
SHRA/TSRA OVERNIGHT. CONFIDENCE IS RATHER LOW THAT ANY ACTIVITY WILL
BE REMAINING...SO THIS MAY BE ABLE TO BE REMOVED LATER THIS EVENING
AND GO WTIH A DRY OVERNIGHT.
TUESDAY THROUGH THURSDAY...
LEADING VORT WILL PIVOT EAST OF THE REGION EARLY TUE...WITH THE DRY
SLOT STILL BEING PROGGED TO KEEP DRY CONDS OVER THE FORECAST AREA
THRU THE BULK OF THE DAY TUE. BY MID/LATE AFTN THE MID-LVL TROUGH
AXIS APPROACHES FROM THE NORTHWEST...AND WITH ANY SFC
DESTABILIZATION...A FEW ISO TSRA COULD DEVELOP FROM THE STEEP LAPSE
RATES AND COOLING IN THE MID-LVLS. WITH THE FLOW REMAINING
PROGRESSIVE...THE TROUGH AXIS SLIDES OVERHEAD BY 03Z WED AND SHUD
BRING A QUICK END TO ANY DIURNALLY DRIVEN SHRA/TSRA ACROSS THE CWFA
WITH A DRY OVERNIGHT PERIOD. GUIDANCE IS ALSO INDICATING A TRAILING
WEAK TROUGH SLIDING INTO THE CENTRAL PLAINS WED MORNING...WITH AN
ABUNDANCE OF LOW/MID LVL MOISTURE WRAPPING AROUND THE WESTERN GREAT
LAKES REGION. THIS WILL LIKELY BRING A CHC FOR LIGHT SHOWERS FOR
WED. WITH CONSIDERABLE SOLAR SHIELDING WED...AND A THERMAL TROUGH OF
6 TO 8 DEG C OVERHEAD...TEMPS COULD STRUGGLE TO WARM BEYOND 70-74
FOR NORTHERN IL/NORTHWEST IN. IT IS PLAUSIBLE THAT A FEW POINTS IN
FAR NORTHERN IL THAT REMAIN IN THE UPR 60S WED AFTN.
BROAD TROUGH THEN PUSHES EAST WED NGT...WITH SFC ANTI-CYCLONIC
FEATURE BUILDING IN FROM THE WEST. THIS FEATURE WILL HELP TO DRY THE
LOW-LEVELS OUT AND ALLOW WINDS TO TURN NORTHWEST TO NORTH. THEN FOR
THUR THE NORHTERLY DRY FLOW WILL BRING SUNNY SKIES WITH TEMPS
GENERALLY IN THE 70S. A LAKE BREEZE LOOKS LIKELY AND COULD KEEP ON
ONSHORE FLOW FOR THE ADJACENT LAKESHORE COMMUNITIIES AND TEMPS IN
THE 60S.
CONFIDENCE...HIGH.
FRIDAY THROUGH MONDAY...
ENSEMBLES CONTINUE TO PROG A RIDGE ACROSS THE CANADIAN ROCKIES FOR
THE END OF THE WORK WEEK...ALLOWING A DOWNSTREAM TROUGH TO BE OVER
THE GREAT LAKES/NORTHEAST CONUS. AS THE WEEKEND PROGRESSES THE WAVE
WILL BEGIN TO RELAX...ALTHOUGH THE MID-LVL TROUGH WILL DRIFT EAST BY
SAT/SUN OVER THE UPPER MIDWEST/NORTH OF LAKE SUPERIOR. THIS SHUD
ALLOW TEMPS TO SLOWLY RETURN TO NEAR SEASONAL CONDS. ALTHOUGH AS THE
WEEKEND PROGRESSES...THE LONGWAVE PATTERN DOES TRANSITION INTO A
SEMI-ZONAL FLOW WITH HEIGHTS STEADILY INCREASING ACROSS THE ENTIRE
CONUS. TEMPS FOR FRI SHUD CONTINUE TO BE SUB-SEASONAL IN THE 70S
NEAR 80...THEN BACK TO ARND 80 OR LOW 80S FOR THE WEEKEND. EARLY
NEXT WEEK THE PATTERN DOES APPEAR TO POINT TOWARDS TEMPS RETURNING
TO LOW/MID 80S. IN ADDITION TO THE SEMI-ZONAL FLOW...IT DOES SUPPORT
A QUICK WEST-EAST FLOW OF WEAK WAVES. THIS COULD EASILY BRING A LOW
CHC POPS FOR THE WEEKEND/EARLY NEXT WEEK.
CONFIDENCE...HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* SOUTHWEST WINDS BECOMING MORE SOUTHERLY WITH INCREASING
SPEEDS/GUSTS THIS AFTERNOON.
* TSRA LATE AFTERNOON THROUGH MID EVENING WITH STRONG/ERRATIC
WINDS AND HEAVY RAIN.
* POSSIBLE MVFR CONDITIONS UNDER HEAVIEST THUNDERSTORM.
RODRIGUEZ
//DISCUSSION...UPDATED 18Z...
RELATIVELY QUIET CONDITIONS TO START THE FORECAST PERIOD WITH
SOUTHWEST WINDS AND ONLY HIGH LEVEL CIRRUS IN PLACE. THIS WILL
LIKELY CHANGE LATER THIS AFTERNOON AND EVENING AS A COMPLEX OF
THUNDERSTORMS CURRENTLY OVER IOWA TRACKS EAST TOWARDS THE
TERMINALS. CURRENTLY MONITORING THUNDERSTORMS OVER CENTRAL IOWA
WHICH WILL EITHER BE THE THUNDERSTORMS TO MOVE THROUGH THE
TERMINALS LATER TODAY OR WILL AT LEAST BE ASSOCIATED WITH THE
EXPECTED THUNDERSTORMS. HIGH CONFIDENCE DOES EXIST WITH THE
POTENTIAL FOR THUNDERSTORMS OVER THE TERMINALS LATE THIS AFTERNOON
INTO THE EVENING...BUT THERE DOES REMAIN SOME UNCERTAINTY WITH
EXACT TIMING. IF THE SYSTEM BECOMES MORE ORGANIZED OVER THE NEXT
ONE TO TWO HOURS...IT WOULD THEN QUICKLY TRACK EAST TOWARDS THE
TERMINALS AND POSSIBLY REACH THEM BEFORE THE TAF TIMES OF AROUND
23Z. IF NOT...THE CURRENT TIME...IF NOT LATER...WOULD BE A MORE
PREFERRED TIMING. WILL CONTINUE TO CLOSELY MONITOR TRENDS AND
ADJUST TIMES AS NECESSARY. THESE STORMS DO HAVE THE POTENTIAL TO
BE SEVERE...WITH HIGH WIND GUSTS IN EXCESS OF 70 MPH POSSIBLE. NOT
ONLY IS LOWER VIS LIKELY WITH THESE THUNDERSTORMS...BUT MVFR CIGS
ARE A DEFINITE POSSIBILITY AS WELL. DEPARTING COMPLEX LATER THIS
EVENING WILL RESULT IN LINGERING VFR CIGS TONIGHT...WITH A HIGHLY
ERRATIC WIND FIELD LIKELY. DID NOT CONVEY THE POSSIBLE WIND FIELD
ON THE BACKSIDE OF THE THUNDERSTORMS AND WILL LIKELY ADD THIS
LATER...BUT WITH SOME TEMPORARY EASTERLY COMPONENT POSSIBLE BEFORE
THEY SHIFT BACK TO THE SOUTHWEST.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM HIGH CONFIDENCE WITH WIND SPEED/GUSTS/DIRECTION DURING
FORECAST PERIOD...LOW CONFIDENCE OF WIND DIRECTION DURING AND
AFTER THUNDERSTORMS.
* HIGH FOR TSRA LATE AFTERNOON THROUGH MID EVENING...MEDIUM ON
TIMING.
* MEDIUM CONFIDENCE FOR MVFR CONDITIONS.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
* TUESDAY NIGHT...DRY/VFR.
* WEDNESDAY...CHANCE OF SHRA.
* THURSDAY THROUGH SATURDAY...DRY/VFR.
* SUNDAY...SLIGHT CHANCE OF TSRA.
&&
.MARINE...
303 PM CDT
PRIMARY MARINE CONCERN IS OVER THE NEARSHORE WATERS AND SOUTH HALF
THIS EVENING AS AN INTENSE COMPLEX OF THUNDERSTORMS LIKELY HOLDS
TOGETHER AND BRINGS A PERIOD OF DANGEROUSLY STRONG WINDS AND
FREQUENT LIGHTNING. HAVE LEFT THE DENSE FOG ADVISORY FOR THE NORTH
HALF UNTIL THIS EVENING. BEFORE CLOUDS MOVED OVERHEAD...VISIBLE
SATELLITE SHOWED A BANK OF FOG COVERING MUCH OF THE NORTHERN PART
OF THE LAKE. SYNOPTIC SOUTHERLY WINDS STILL MAY BECOME STRONG
ENOUGH FOR SMALL CRAFT CRITERIA THIS EVENING IN THE NEARSHORE BUT
DO NOT HAVE ENOUGH CONFIDENCE TO HOIST AN ADVISORY.
HAVE BETTER CONFIDENCE IN SMALL CRAFT WIND CRITERIA BEING MET ON
TUESDAY. TIGHT PRESSURE GRADIENT AND DEEP MIXING FROM LAND WILL
LIKELY RESULT IN WEST-SOUTHWEST WINDS AROUND 20 KT AND FREQUENT
GUSTS TO 25 KT OR EVEN A BIT HIGHER LATE TUESDAY MORNING THROUGH
LATE TUESDAY AFTERNOON. HAVE SOME CONCERN THAT GUSTY WINDS MAY
EXTEND A BIT INTO TUESDAY EVENING. HIGH PRESSURE WILL SPREAD OVER
THE LAKE THURSDAY INTO FRIDAY AND ONLY SLOWLY MOVE EASTWARD ON
SATURDAY. AN FAIRLY EXTENDED PERIOD OF LIGHT WINDS WITH DIRECTIONS
NEAR THE SHORES CONTROLLED BY LAKE BREEZE INFLUENCES BY DAY WILL
ENSUE WEDNESDAY NIGHT THROUGH AT LEAST FRIDAY NIGHT. MODEST
SOUTHERLY WINDS WILL DEVELOP ON SATURDAY AS THE HIGH SLIDES EAST.
RC
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032 UNTIL 4 AM TUESDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002 UNTIL 4 AM TUESDAY.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ868 UNTIL 9 PM MONDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-
LMZ745...9 AM TUESDAY TO 7 PM TUESDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
429 PM EDT MON JUN 30 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 355 PM EDT MON JUN 30 2014
COLD FRONT AND UPPER TROUGH WILL MOVE THROUGH THE AREA THROUGH
WEDNESDAY...CONTINUING THE RECENT ACTIVE PATTERN. HOWEVER...LARGE
DOME OF SURFACE HIGH PRESSURE IN THE WAKE OF THIS FRONT WILL BRING
A RETURN TO COOLER TEMPERATURES AND DRY WEATHER FOR THE LAST HALF
OF THE WEEK AND INTO THE HOLIDAY WEEKEND ACROSS CENTRAL INDIANA.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 355 PM EDT MON JUN 30 2014
AIRMASS IS RECOVERING RELATIVELY QUICKLY FROM MORNING CONVECTION
THAT HAS ONLY JUST CLEARED THE FORECAST AREA IN THE LAST COUPLE OF
HOURS. HOWEVER...MESOANALYSIS SHOWS AMPLE CONVECTIVE INHIBITION
REMAINS IN PLACE AND AN INSTABILITY GRADIENT LAID OUT FROM NW TO
SE FROM MAIN CONVECTIVE COMPLEX IN IOWA THROUGH ILLINOIS AND INTO
INDIANA. MODELS...AS HAS BEEN THE CASE IN RECENT DAYS...ARE
STRUGGLING AND HAVE PRESENTED SOME DIFFERING OPINIONS AS TO THE
EVOLUTION OF THE MCS. 4KM SPC WRF SHOWS INITIAL COMPLEX MOVING
GENERALLY EASTWARD THROUGH NORTHERN ILLINOIS AND NORTHERN
INDIANA...WHILE SECONDARY COMPLEX FORMS ON SOUTHERN FLANK AND
FOLLOWS INSTABILITY GRADIENT SOUTHEAST INTO CENTRAL ILLINOIS AND
SOUTHWEST INDIANA. HRRR KEEPS MOST OF THE CONVECTION TO OUR NORTH.
FOR NOW...EXPECT A GENERAL EASTWARD MOTION WITH A TREND
SOUTHEASTWARD ALONG THE INSTABILITY GRADIENT FOR THE MAIN
COMPLEX AS COLD POOL ESTABLISHES...PUTTING THE SOUTHERN PORTION OF
THE MCS IN THE NORTHWESTERN FORECAST AREA AROUND 03-05Z. WILL
CARRY LIKELY POPS THERE WITH LESSER POPS AS ONE MOVES SOUTHEAST.
INSTABILITY WILL REMAIN AMPLE TO SUSTAIN THE COMPLEX OVERNIGHT AND
THUS SEVERE THREAT WILL EXIST MOST OF THE NIGHT. DAMAGING WINDS
ARE THE NUMBER ONE THREAT. LARGE HAIL WILL BE A THREAT BUT A
LESSER ONE WITH FREEZING LEVELS APPROACHING 15KFT. THIS DEEP WARM
CLOUD LAYER AND PRECIPITABLE WATER VALUES APPROACHING TWO
INCHES...OR 150-170 PERCENT OF NORMAL FOR THE AREA...WILL PRESENT
A CLEAR HYDROLOGIC THREAT...ESPECIALLY GIVEN THE REPEATED ROUNDS
OF RAIN RECEIVED ACROSS THE AREA IN RECENT WEEKS...ALTHOUGH
RELATIVELY FAST STORM MOTIONS WILL MITIGATE THAT SOMEWHAT.
MIN TEMPS SHOULD END UP NEAR OR JUST ABOVE PERSISTENCE PER LOW
LEVEL THERMAL PROGS...GENERALLY IN THE LOW TO MID 70S ACROSS THE
AREA.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY/...
ISSUED AT 355 PM EDT MON JUN 30 2014
WEAKENING COMPLEX OF STORMS MAY STILL BE OVER THE AREA EARLY
TUESDAY WITH THE FRONT TRAILING IT. MAY SEE STORMS REDEVELOPING
ACROSS THE SOUTHEASTERN PORTIONS OF THE FORECAST AREA TOMORROW
BEFORE THE FRONT MOVES THROUGH THE AREA. WILL EVEN HAVE TO CARRY A
SLIGHT CHANCE ACROSS THE SOUTH EARLY TOMORROW NIGHT.
SHOULD BE DRY LATE TOMORROW NIGHT INTO EARLY WEDNESDAY...BUT SOME
SHOWERS WILL BE POSSIBLE AS THE UPPER TROUGH SWINGS THROUGH
WEDNESDAY AFTERNOON WITH SOME SHALLOW INSTABILITY AND STEEP LOW
LEVEL LAPSE RATES. HOWEVER...K INDICES ARE LOW ENOUGH THAT THUNDER
APPEARS UNLIKELY AND WILL ONLY CARRY SHOWERS. REMAINDER OF THE
SHORT TERM WILL BE DRY AS HIGH PRESSURE QUICKLY BUILDS INTO THE
AREA.
MOS BLEND NUMBERS APPEARED REASONABLE ON TEMPERATURES BASED ON 850
TEMPS AND LOW LEVEL THICKNESSES.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
ISSUED AT 235 PM EDT MON JUN 30 2014
MODELS ARE CLOSE ENOUGH THAT THE ALLBLEND INITIALIZATION CAN BE
ACCEPTED FOR MOST ITEMS.
HIGH PRESSURE WILL PROVIDE COOL AND DRY CONDITIONS FOR THE FIRST
HALF OF THE LONG TERM. A WARM FRONT AND WEAK UPPER SYSTEM WILL BEGIN
TO INFLUENCE THE AREA DURING THE SECOND HALF.
00Z ECMWF IS MUCH FASTER AND MORE AGGRESSIVE IN BRINGING IN RAIN
WITH THE FRONT...AS EARLY AS SUNDAY. 12Z GFS IS MUCH DRIER. HOWEVER
GFS ENSEMBLES ARE IN BETWEEN. FOR NOW WILL GO DRY ON SUNDAY AND ONLY
LOW POPS SUNDAY NIGHT AND MONDAY GIVEN THE HIGH UNCERTAINTY IN
TIMING OF RAIN. TEMPERATURES WILL RETURN TO NORMAL BY MONDAY AS THE
WARM FRONT MOVES IN.
&&
.AVIATION /DISCUSSION FOR 301800Z TAF ISSUANCE/...
ISSUED AT 427 PM EDT MON JUN 30 2014
2030Z UPDATE...NO CHANGES NEEDED AT THIS TIME. PREVIOUS DISCUSSION
FOLLOWS.
VFR CONDITIONS EXPECTED MOST OF THE PERIOD...WITH IFR CONDITIONS
POSSIBLE IN ANY CONVECTION...ESPECIALLY OVERNIGHT.
THUNDER SHOULD BE OUT OF THE SITES BY VALID TIME. RAIN HAS CLEARED
OUT THE LOWER CLOUDS AT THE SITES...SO ONLY EXPECT SCATTERED LOWER
CLOUDS WITH A HIGH CLOUD CEILING THIS AFTERNOON. IF ENOUGH SUN
BREAKS OUT WOULD NOT BE SURPRISED TO SEE BRIEF PERIODS OF BROKEN
CUMULUS...ESPECIALLY AT THE SOUTHERN SITES.
THUNDERSTORM COMPLEX WILL MOVE INTO NORTHERN ILLINOIS AND NORTHERN
INDIANA LATE THIS EVENING INTO THE OVERNIGHT. MUCH UNCERTAINTY
EXISTS ON HOW FAR SOUTH THESE STORMS WILL GET OVERNIGHT...SO JUST
WENT PROB30 EVERYWHERE FOR NOW. AT THE MOMENT BELIEVE KLAF AND KIND
WOULD HAVE THE BEST CHANCES TO SEE STORMS OVERNIGHT.
WINDS TONIGHT SHOULD REMAIN UP ENOUGH TO PREVENT FOG...BUT WILL HAVE
TO WATCH CLOSELY. COLD FRONT COULD BRING ADDITIONAL SHOWERS AFTER
12Z TUESDAY SO WENT VCSH ALL SITES.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...NIELD
NEAR TERM...NIELD
SHORT TERM...NIELD
LONG TERM...50
AVIATION...SMF
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AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
356 PM EDT MON JUN 30 2014
.UPDATE...
THE SYNOPSIS...NEAR TERM AND SHORT TERM SECTIONS HAVE BEEN
UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 355 PM EDT MON JUN 30 2014
COLD FRONT AND UPPER TROUGH WILL MOVE THROUGH THE AREA THROUGH
WEDNESDAY...CONTINUING THE RECENT ACTIVE PATTERN. HOWEVER...LARGE
DOME OF SURFACE HIGH PRESSURE IN THE WAKE OF THIS FRONT WILL BRING
A RETURN TO COOLER TEMPERATURES AND DRY WEATHER FOR THE LAST HALF
OF THE WEEK AND INTO THE HOLIDAY WEEKEND ACROSS CENTRAL INDIANA.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 355 PM EDT MON JUN 30 2014
AIRMASS IS RECOVERING RELATIVELY QUICKLY FROM MORNING CONVECTION
THAT HAS ONLY JUST CLEARED THE FORECAST AREA IN THE LAST COUPLE OF
HOURS. HOWEVER...MESOANALYSIS SHOWS AMPLE CONVECTIVE INHIBITION
REMAINS IN PLACE AND AN INSTABILITY GRADIENT LAID OUT FROM NW TO
SE FROM MAIN CONVECTIVE COMPLEX IN IOWA THROUGH ILLINOIS AND INTO
INDIANA. MODELS...AS HAS BEEN THE CASE IN RECENT DAYS...ARE
STRUGGLING AND HAVE PRESENTED SOME DIFFERING OPINIONS AS TO THE
EVOLUTION OF THE MCS. 4KM SPC WRF SHOWS INITIAL COMPLEX MOVING
GENERALLY EASTWARD THROUGH NORTHERN ILLINOIS AND NORTHERN
INDIANA...WHILE SECONDARY COMPLEX FORMS ON SOUTHERN FLANK AND
FOLLOWS INSTABILITY GRADIENT SOUTHEAST INTO CENTRAL ILLINOIS AND
SOUTHWEST INDIANA. HRRR KEEPS MOST OF THE CONVECTION TO OUR NORTH.
FOR NOW...EXPECT A GENERAL EASTWARD MOTION WITH A TREND
SOUTHEASTWARD ALONG THE INSTABILITY GRADIENT FOR THE MAIN
COMPLEX AS COLD POOL ESTABLISHES...PUTTING THE SOUTHERN PORTION OF
THE MCS IN THE NORTHWESTERN FORECAST AREA AROUND 03-05Z. WILL
CARRY LIKELY POPS THERE WITH LESSER POPS AS ONE MOVES SOUTHEAST.
INSTABILITY WILL REMAIN AMPLE TO SUSTAIN THE COMPLEX OVERNIGHT AND
THUS SEVERE THREAT WILL EXIST MOST OF THE NIGHT. DAMAGING WINDS
ARE THE NUMBER ONE THREAT. LARGE HAIL WILL BE A THREAT BUT A
LESSER ONE WITH FREEZING LEVELS APPROACHING 15KFT. THIS DEEP WARM
CLOUD LAYER AND PRECIPITABLE WATER VALUES APPROACHING TWO
INCHES...OR 150-170 PERCENT OF NORMAL FOR THE AREA...WILL PRESENT
A CLEAR HYDROLOGIC THREAT...ESPECIALLY GIVEN THE REPEATED ROUNDS
OF RAIN RECEIVED ACROSS THE AREA IN RECENT WEEKS...ALTHOUGH
RELATIVELY FAST STORM MOTIONS WILL MITIGATE THAT SOMEWHAT.
MIN TEMPS SHOULD END UP NEAR OR JUST ABOVE PERSISTENCE PER LOW
LEVEL THERMAL PROGS...GENERALLY IN THE LOW TO MID 70S ACROSS THE
AREA.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY/...
ISSUED AT 355 PM EDT MON JUN 30 2014
WEAKENING COMPLEX OF STORMS MAY STILL BE OVER THE AREA EARLY
TUESDAY WITH THE FRONT TRAILING IT. MAY SEE STORMS REDEVELOPING
ACROSS THE SOUTHEASTERN PORTIONS OF THE FORECAST AREA TOMORROW
BEFORE THE FRONT MOVES THROUGH THE AREA. WILL EVEN HAVE TO CARRY A
SLIGHT CHANCE ACROSS THE SOUTH EARLY TOMORROW NIGHT.
SHOULD BE DRY LATE TOMORROW NIGHT INTO EARLY WEDNESDAY...BUT SOME
SHOWERS WILL BE POSSIBLE AS THE UPPER TROUGH SWINGS THROUGH
WEDNESDAY AFTERNOON WITH SOME SHALLOW INSTABILITY AND STEEP LOW
LEVEL LAPSE RATES. HOWEVER...K INDICES ARE LOW ENOUGH THAT THUNDER
APPEARS UNLIKELY AND WILL ONLY CARRY SHOWERS. REMAINDER OF THE
SHORT TERM WILL BE DRY AS HIGH PRESSURE QUICKLY BUILDS INTO THE
AREA.
MOS BLEND NUMBERS APPEARED REASONABLE ON TEMPERATURES BASED ON 850
TEMPS AND LOW LEVEL THICKNESSES.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
ISSUED AT 235 PM EDT MON JUN 30 2014
MODELS ARE CLOSE ENOUGH THAT THE ALLBLEND INITIALIZATION CAN BE
ACCEPTED FOR MOST ITEMS.
HIGH PRESSURE WILL PROVIDE COOL AND DRY CONDITIONS FOR THE FIRST
HALF OF THE LONG TERM. A WARM FRONT AND WEAK UPPER SYSTEM WILL BEGIN
TO INFLUENCE THE AREA DURING THE SECOND HALF.
00Z ECMWF IS MUCH FASTER AND MORE AGGRESSIVE IN BRINGING IN RAIN
WITH THE FRONT...AS EARLY AS SUNDAY. 12Z GFS IS MUCH DRIER. HOWEVER
GFS ENSEMBLES ARE IN BETWEEN. FOR NOW WILL GO DRY ON SUNDAY AND ONLY
LOW POPS SUNDAY NIGHT AND MONDAY GIVEN THE HIGH UNCERTAINTY IN
TIMING OF RAIN. TEMPERATURES WILL RETURN TO NORMAL BY MONDAY AS THE
WARM FRONT MOVES IN.
&&
.AVIATION /DISCUSSION FOR 301800Z TAF ISSUANCE/...
ISSUED AT 115 PM EDT MON JUN 30 2014
VFR CONDITIONS EXPECTED MOST OF THE PERIOD...WITH IFR CONDITIONS
POSSIBLE IN ANY CONVECTION...ESPECIALLY OVERNIGHT.
THUNDER SHOULD BE OUT OF THE SITES BY VALID TIME. RAIN HAS CLEARED
OUT THE LOWER CLOUDS AT THE SITES...SO ONLY EXPECT SCATTERED LOWER
CLOUDS WITH A HIGH CLOUD CEILING THIS AFTERNOON. IF ENOUGH SUN
BREAKS OUT WOULD NOT BE SURPRISED TO SEE BRIEF PERIODS OF BROKEN
CUMULUS...ESPECIALLY AT THE SOUTHERN SITES.
THUNDERSTORM COMPLEX WILL MOVE INTO NORTHERN ILLINOIS AND NORTHERN
INDIANA LATE THIS EVENING INTO THE OVERNIGHT. MUCH UNCERTAINTY
EXISTS ON HOW FAR SOUTH THESE STORMS WILL GET OVERNIGHT...SO JUST
WENT PROB30 EVERYWHERE FOR NOW. AT THE MOMENT BELIEVE KLAF AND KIND
WOULD HAVE THE BEST CHANCES TO SEE STORMS OVERNIGHT.
WINDS TONIGHT SHOULD REMAIN UP ENOUGH TO PREVENT FOG...BUT WILL HAVE
TO WATCH CLOSELY. COLD FRONT COULD BRING ADDITIONAL SHOWERS AFTER
12Z TUESDAY SO WENT VCSH ALL SITES.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...NIELD
NEAR TERM...NIELD
SHORT TERM...NIELD
LONG TERM...50
AVIATION...50
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AREA FORECAST DISCUSSION
NWS DODGE CITY KS
300 PM CDT Mon Jun 30 2014
...UPDATE TO LONG TERM...
.SHORT TERM...(This evening through Tuesday)
ISSUED AT 206 PM CDT MON JUN 30 2014
RAP and NAM verified well with the 18z surface analysis with the
surface cold front across southwest Kansas. A surface
trough/dry line extended south of this cold front into the
panhandle of Oklahoma and Texas. Warm air was located above these
surface boundaries with the RAP still suggesting a 700mb
temperature of greater than +16c lingers across southwest Kansas.
Given these warm temperatures any convection does develop along
these two boundaries am expecting this will occur after 23z.
Scattered convection is expected to develop along the cold front
late today. 0-6km shear is forecast to be 30 to 35 knots and the
CAPE values are expected to exceed 3500 j/kg at 00z Tuesday. Given
the instability and shear early this evening any storm that does
develop may become severe with the main hazard begin strong
damaging winds and golf ball size hail.
Thunderstorms will become more widespread across southwest and
south central Kansas early tonight. The latest RAP, NAM, and GFS
remain in good agreement keeping an area of moisture and improving
850mb-700mb frontogenesis over southwest Kansas after 00z Tuesday
as an upper level trough moves across Central High Plains.
Preciptable water values at 00z Tuesday were forecast to be at 1
to 1.5 inches. Given the forcing and moisture just north of the
cold front across southwest and south central Kansas early tonight
along with improving upper level dynamics front ahead of the upper
trough and near location of the right exit region of an upper
level jet will continue to favor thunderstorms increasing in areal
coverage between 00z Tuesday and 06z Tuesday with periods of heavy
rainfall being possible. At this time based on the location of
where the heavier rainfall is expected overnight will not be
issuing a flash flood watch but will mention flooding concerns in
the hazardous weather outlook.
Precipitation will taper off from northwest to southeast early
Tuesday as the upper level trough crosses western Kansas. 850mb
temperature trends from 00z Tuesday to 00z Wednesday suggests
highs mainly in the low to mid 80s. Given lingering afternoon
cloud cover near the Oklahoma border will trim temperatures down a
few degrees here from the later guidance.
.LONG TERM...(Tuesday night through Monday)
ISSUED AT 300 PM CDT MON JUN 30 2014
Medium range models indicate an upper level shortwave dropping
southeast out of the Northern Rockies into the Western High Plains
early Wednesday then turning more eastward into the Central Plains
by Wednesday night. Meanwhile, upper level ridging will slowly
transition across the Intermountain West turning the flow aloft
more northwesterly across the Western High Plains toward the end
of the week. As the flow aloft weakens, precip chances will be
limited across much of central and western Kansas. However, a
near stationary frontal boundary just south of the Oklahoma border
may provide the focus for a slight chance of isolated thunderstorms
near and along the Oklahoma state line Tuesday night into early
Wednesday. The northwesterly flow aloft will persist through the
end of the week while the frontal boundary to our south extends
back north into eastern Colorado. As H5 vort maxima crest the
ridge and drop southeast off the Rockies, thunderstorm development
is likely lee of the front range each afternoon Thursday and
Friday. A few isolated thunderstorms could potentially drift into
western Kansas each evening.
Below normal temperatures are expected Wednesday as surface high
pressure moves southeast out of the Northern Plains into the Central
Plains of eastern Kansas. This will reinforce the slightly cooler
air mass in place across western Kansas with H85 temperatures
ranging from the upper teens(C) across central Kansas to the
lower 20s(C) closer to the Colorado border. Even with decreasing
cloud cover expected, look for highs struggling to reach the 80s(F)
across central and portions of southwest Kansas Wednesday afternoon.
A gradual warming trend is then forecast through the weekend as
upper level ridging approaches from the west, pushing highs back
into the 90s(F) by Saturday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
ISSUED AT 1209 PM CDT MON JUN 30 2014
Cold front will cross southwest Kansas this afternoon. As this
front passes a gusty southwest winds will become northwest at 10
to 15knots. Given the general agreement on timing from the RAP,
HRRR, and NAM will stay close to the latest MET guidance on timing
of this wind shift. Moisture this afternoon and early tonight will
be located just above the elevated warm layer so VFR conditions
are expected through early this evening. Thunderstorms are
expected in increase in areal coverage near and south of the
Garden City and Dodge City airport after 00z Tuesday as an upper level
disturbance begins to cross the Central High Plains. Although the
better chances may end up being south of these airports will keep
a tempo group of thunderstorms going but adjusted timing more
towards the slightly slower 12z model runs. Winds and reduced
visibility from heavy rainfall will be the main hazard when these
storms pass early tonight.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 63 82 60 83 / 60 30 10 10
GCK 62 82 59 83 / 30 20 10 10
EHA 62 78 59 83 / 70 30 20 10
LBL 64 80 61 83 / 80 30 20 10
HYS 62 84 59 80 / 20 20 0 0
P28 68 83 64 86 / 90 40 20 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Burgert
LONG TERM...JJohnson
AVIATION...Burgert
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
210 PM CDT Mon Jun 30 2014
...Updated short term discussion...
.SHORT TERM...(This evening through Tuesday)
ISSUED AT 206 PM CDT MON JUN 30 2014
RAP and NAM verified well with the 18z surface analysis with the
surface cold front across southwest Kansas. A surface
trough/dry line extended south of this cold front into the
panhandle of Oklahoma and Texas. Warm air was located above these
surface boundaries with the RAP still suggesting a 700mb
temperature of greater than +16c lingers across southwest Kansas.
Given these warm temperatures any convection does develop along
these two boundaries am expecting this will occur after 23z.
Scattered convection is expected to develop along the cold front
late today. 0-6km shear is forecast to be 30 to 35 knots and the
CAPE values are expected to exceed 3500 j/kg at 00z Tuesday. Given
the instability and shear early this evening any storm that does
develop may become severe with the main hazard begin strong
damaging winds and golf ball size hail.
Thunderstorms will become more widespread across southwest and
south central Kansas early tonight. The latest RAP, NAM, and GFS
remain in good agreement keeping an area of moisture and improving
850mb-700mb frontogenesis over southwest Kansas after 00z Tuesday
as an upper level trough moves across Central High Plains.
Preciptable water values at 00z Tuesday were forecast to be at 1
to 1.5 inches. Given the forcing and moisture just north of the
cold front across southwest and south central Kansas early tonight
along with improving upper level dynamics front ahead of the upper
trough and near location of the right exit region of an upper
level jet will continue to favor thunderstorms increasing in areal
coverage between 00z Tuesday and 06z Tuesday with periods of heavy
rainfall being possible. At this time based on the location of
where the heavier rainfall is expected overnight will not be
issuing a flash flood watch but will mention flooding concerns in
the hazardous weather outlook.
Precipitation will taper off from northwest to southeast early
Tuesday as the upper level trough crosses western Kansas. 850mb
temperature trends from 00z Tuesday to 00z Wednesday suggests
highs mainly in the low to mid 80s. Given lingering afternoon
cloud cover near the Oklahoma border will trim temperatures down a
few degrees here from the later guidance.
.LONG TERM...(Tuesday through Sunday)
ISSUED AT 356 AM CDT MON JUN 30 2014
By Tuesday, convective chances should be rapidly diminishing across
the northern sections of the forecast area, and remaining modestly
near the OK/KS line in vicinity of the 850-700 mb frontal/convergence
zone. Easterly upslope and relatively moist surface flow associated
with the large plains high pressure could cause extensive
cloudiness across positions of the forecast area leading to
dramatically cooler conditions for this time of the year. The GEM
(Canadian model) forecast highs only in the low 70s on Tuesday
which could occur with he right amount of thick cloudiness. We
used the consensus of the raw model output which still hovers
temperatures around 80 degrees on Tuesday and through the middle
of the week. The Global models begin to hint at convective chances
again by around mid week, however the broad upper flat ridge will
begin to have greater influence. This would tend to be less
favorable for widespread organized storms, but certainly not
completely hinder isolated severe storms. Temperatures should soar
back toward normal early July highs by late in the week through
the weekend. With dew point temperatures in the 60s still in place
and mid level temperatures not exceeding the low teens (C), it is
plausible isolated high cape/low shear pulse type convection could
develop anytime adequate surface convergence is present late in
the week.
&&
.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
ISSUED AT 1209 PM CDT MON JUN 30 2014
Cold front will cross southwest Kansas this afternoon. As this
front passes a gusty southwest winds will become northwest at 10
to 15knots. Given the general agreement on timing from the RAP,
HRRR, and NAM will stay close to the latest MET guidance on timing
of this wind shift. Moisture this afternoon and early tonight will
be located just above the elevated warm layer so VFR conditions
are expected through early this evening. Thunderstorms are
expected in increase in areal coverage near and south of the
Garden City and Dodge City airport after 00z Tuesday as an upper level
disturbance begins to cross the Central High Plains. Although the
better chances may end up being south of these airports will keep
a tempo group of thunderstorms going but adjusted timing more
towards the slightly slower 12z model runs. Winds and reduced
visibility from heavy rainfall will be the main hazard when these
storms pass early tonight.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 63 82 60 84 / 60 30 10 10
GCK 62 82 59 81 / 30 20 10 10
EHA 62 78 59 79 / 70 30 20 10
LBL 64 80 61 82 / 80 30 20 10
HYS 62 84 59 80 / 20 20 0 0
P28 68 83 64 86 / 90 40 20 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Burgert
LONG TERM...Russell
AVIATION...Burgert
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1245 PM CDT Mon Jun 30 2014
...Update to aviation forecast discussion...
.SHORT TERM...(Today and Tonight)
Issued at 340 AM CDT MON JUN 30 2014
08Z profiler data shows the low level jet of 30 to 40 KTS continues
to gradually veer to the southwest becoming more parallel to the
front across central NEB. Meanwhile, water vapor imagery shows a
shortwave rotating through ID and MT with nearly zonal flow from the
west coast into the central plains. Surface obs indicate a very warm
and moist airmass remains in place across the forecast area.
With the low level jet veering southwest, convergence along the
boundary is likely to diminish. Besides that any convergence along
the boundary for elevated storms should remain to the north of the
area. Therefore think much of the nocturnal precip will remain north
of the forecast area. Will keep a token slight chance across the
northern tier of counties as the light shower activity spreads east.
The shortwave rotating through the mean flow over the northern
plains is expected to help push the cold front south into the area
by this afternoon. With the front lifting a very moist and unstable
airmass, thunderstorms are likely to develop in eastern KS before
moving to the east. Deep layer shear is expected to be sufficient
for supercell storms and low level shear and LCL heights suggest
tornadoes will be possible. The main questions are how widespread
the convection may be and when storms could initiate. Models show a
low level cap over the warm sector around 850 MB until late in the
afternoon, not unlike what was observed yesterday. But eventually
the forecast soundings cool the layer removing any inhibition. It is
unclear as to where the cooling is coming from as winds within the
layer remain from the southwest. Additionally the stronger forcing
associated with the shortwave over the northern plains appears to
remain just north of the forecast area. So am concerned that these
two factors may limit the coverage of storms in the later afternoon
and early evening. Nevertheless any storm that forms could quickly
become severe with a potential for tornadoes due to the instability
greater than 4000 J/kg and shear progged by the models. At this
time, think thunderstorm initiation may occur over eastern KS with
storms moving to the east. The thunderstorm activity is expected to
push south through the night tonight as the front slowly moves
south.
Highs today should be several degrees warmer than yesterday as there
should be less high level clouds to start the day off and models
laying the thermal ridge over into northeast KS along the surface
trough. There is some uncertainty in how deep the boundary layer
will mix and in turn how warm temps will get. The RAP has had a bias
to mixing the boundary layer to deep and feel it is way to warm.
Since there is so much humidity in the air, opted to keep highs in
the lower and middle 90s. This humidity however will cause heat
indices to range from 100 to 105 this afternoon. If it looks like
temps could end up a degree or two warmer with dewpoints holding in
the 70s, a heat advisory may be needed. Lows tonight should fall
into the 60s with some drier air advecting in from the north along
with some weak cold air advection.
.LONG TERM...(Tuesday through Sunday)
Issued at 340 AM CDT MON JUN 30 2014
The previous active days will begin to calm for next week as a
cooler and more stable airmass settles into place. Still maintained
slight chances for thunderstorms Tuesday with the h85 front across
southern Kansas. Best chances for precipitation will reside near the
Kansas and Oklahoma border. Dry northwest flow aloft continues
Wednesday and Thursday as an expansive surface high builds from the
central plains through the Great Lakes. Light northerly sfc winds
around 10 mph Tuesday gradually will shift to the east and southeast
on Friday as the ridge nudges eastward. Upper ridging begins to
break down, tracking a shortwave trough into the central plains on
Friday evening. Mentioned slight chances for thunderstorms over the
northern CWA at this time, where highest lift resides. Confidence
however, in the southward extent to the trough is low at this time.
Periodic thunderstorms may be possible for next weekend as mid level
flow begins quasi-zonal, allowing for weak waves to pass through.
Unseasonably cooler temperatures Tuesday through Thursday, combined
with dewpoint temperatures in the 50s will make it feel much more
pleasant compared to the previous days. Highs behind the front
Tuesday begin in the low to middle 80s. Weak cool advection with the
surface ridge sliding south will lower highs Wednesday and Thursday
to the upper 70s and lower 80s. Overnight lows during this time with
decent radiational cooling and light winds may reach the upper 50s.
Thermal ridge begins to build over western and central KS
Independence Day as southerly flow returns, peaking highs to the low
and middle 80s. Weekend temps are track to return to near 90 degrees
with overnight lows in the upper 60s.
&&
.AVIATION...(For the 18Z TAFs through 18Z Tuesday Afternoon)
Issued at 1234 PM CDT MON JUN 30 2014
A surface cold front will move southeast across the terminals this
evening. Ahead of the front expect south-southwest winds of 15 to
25 KTS with gusts of 25 to 30 KTS this afternoon. Scattered
thunderstorms will develop along the front late this afternoon and
may affect the terminals after 22Z and last through 03Z TUE.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Wolters
LONG TERM...Bowen
AVIATION...Gargan
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
141 PM EDT MON JUN 30 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 432 AM EDT MON JUN 30 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW WSW FLOW OVER THE
UPR LKS ARND UNSEASONABLY DEEP CLOSED LO CENTERED NEAR LK WINNIPEG.
A SHRTWV THAT ROTATED ACRS NRN LK SUP EARLY THIS MRNG GENERATED SOME
SHOWERS/TS OVER THE CWA EARLIER...BUT VIGOROUS H85-7 DRY ADVCTN
DOWNSTREAM OF VERY DRY 00Z MPX RAOB /WHERE THE 00Z PWAT WAS NEAR
0.75 INCH OR ABOUT 85 PCT OF NORMAL/ AND DNVA/DEEP LYR QVECTOR DVGC
AS WELL AS NOCTURNAL COOLING HAVE ENDED THIS PCPN. HOWEVER...STEEP
LAPSE RATES SHOWN ON THE 00Z MPX RAOB HAVE ALLOWED SOME ISOLD
SHOWERS/TS TO POP UP FM TIME TO TIME OVER NCENTRAL WI AND CENTRAL
UPR MI DESPITE THE LARGER SCALE DRYING TRENDS/NOCTURNAL COOLING.
ANOTHER LARGER CLUSTER OF SHOWERS/TS IS PRESENT OVER SE WI...WHERE
THE SHRTWV IN SCENTRAL MN IS INTERACTING WITH AREA OF HIER H85-7
DEWPTS ON SE FLANK OF DRY WEDGE PUSHING INTO UPR MI. FARTHER
UPSTREAM...THERE ARE SEVERAL SHRTWVS MOVING EWD THRU THE NRN PLAINS
IN THE WLY FLOW ON THE SRN FLANK OF CLOSED LO.
MAIN FCST CONCERNS DURING THIS TIME ARE SHOWER/TS CHANCES...
ESPECIALLY LATE TODAY/TNGT WHEN A STRONGER SHRTWV ROTATING ARND THE
CLOSED LO IS FCST TO MOVE THRU THE UPR MIDWEST.
EARLY THIS MRNG/TODAY...DRY AIR SWEEPING ENEWD WITH H85-5 MEAN LYR
RH DOWN TO 30-40 PCT SHOULD ENSURE DRY WX FOR MOST OF THE CWA THIS
MRNG EVEN THOUGH SHRTWV NOW IN MN AND ASSOCIATED DPVA/SOME DEEP LYR
QVECTOR CNVGC ASSOCIATED WITH SHRTWV NOW OVER SCENTRAL MN WL SWING
ACRS THE AREA. HOWEVER...DID ALLOW FOR SOME LINGERING ISOLD
SHOWERS/TS OVER THE SE HALF OF THE CWA THRU ABOUT 15Z TO ACCOUNT FOR
THIS SHRTWV/FORCING/STEEP H85-5 LAPSE RATES UP TO 8-8.5C/KM. THESE
SHOWERS SHOULD END FOLLOWING THE EXIT OF THE SHRTWV/ARRIVAL OF
DNVA/LARGE SCALE QVECTOR DVGC. PCPN CHCS WL INCRS LATER IN THE AFTN
WITH APRCH OF STRONGER SHRTWV ROTATING ARND THE SSE FLANK OF CLOSED
LO SLOWLY DRIFTING INTO FAR NW ONTARIO. AS THE H85 WINDS BACK A BIT
WITH THE APRCH OF THIS STRONGER DISTURBANCE...MODELS INDICATE HIER
H85-7 DEWPTS/WL SURGE NEWD INTO MAINLY THE SE HALF OF THE CWA. IN
CONCERT WITH ACCOMPANYING DPVA/DEEP LYR QVECTOR CNVGC ASSOCIATED
WITH THE SHRTWV AND H4-2 DVGC IN RRQ OF 100KT H3 JET MAX MOVING THRU
NW LK SUP...WL CONT TO SHOW INCRSG POPS OVER MAINLY THE SCENTRAL
LATE IN THE DAY. CONSIDERING THE RATHER IMPRESSIVE DYNAMICS/MSTR
RETURN THAT IS FCST TO LIFT PWAT CLOSE TO 2 INCHES OVER THE SCENTRAL
BY 00Z /175 PCT OF NORMAL/...PREFER THE HIER POPS A BIT FARTHER TO
THE W/HIER QPF SHOWN BY THE 00Z NAM/REGIONAL CNDN MODEL. AS FOR
TEMPS...EXPECT THE HIEST TEMPS OVER THE INTERIOR W HALF WHERE THERE
WL BE MORE SUNSHINE THRU MUCH OF THE DAY UNTIL CLDS BEGIN TO INCRS
THIS AFTN. DEEP MIXING TO H75 WL SUPPORT HI TEMPS APRCHG 85 AND
ALLOW FOR GUSTY WINDS TO MIX TO THE SFC.
TNGT...VIGOROUS DYNAMICS/MSTR RETURN ARE FCST TO IMPACT MAINLY THE
SE 2/3 OF THE CWA IN THE 00Z-06Z PERIOD AND JUSTIFY SOME CATEGORICAL
POPS OVER THE SE CWA IN THE EVNG BEFORE DNVA/DEEP LYR QVECTOR
DVGC/MID LVL DRYING RETURNS IN THE WAKE OF SHRTWV PASSAGE.
CONSIDERING THE UNSEASONABLY STRONG UPR DYNAMICS...THERE IS SOME
CONCERN AS TO WHETHER ANY OF THE TS COULD BE STRONG TO SEVERE. THE
LATEST SPC CONVECTIVE OUTLOOK SHOWS UPR MI JUST N OF THE THE SLGT
RISK AREA. THE BEST CHC FOR SOME SVR TS WOULD BE WHEN THE DYNAMICS
ARRIVE LATE THIS AFTN WHEN LLVL LAPSE RATES ARE STILL STEEP/DCAPE
WOULD BE HIER FOLLOWING THE DAYTIME HEATING AND WHEN THE LLVL
ENVIRONMENTAL WINDS ARE A UNIDIRECTIONAL SW AND AS HI AS 50 KTS AT
H7. GUSTY WINDS WOULD BE THE MAIN THREAT. DURING THIS EVNG...HEAVY
RA LOOKS TO BE THE MAIN CONCERN WITH RATHER HI FRZG LVL NEAR 13K FT/
MARGINAL MID LVL LAPSE RATES DESPITE SOME FAIRLY STRONG WINDS ALF.
ARRVIAL OF SOME COOLER AIR/MID LVL DRYING WL ALLOW TEMPS OVER THE W
TO FALL INTO THE 50S TNGT. SOME LOCALLY DENSE FOG COULD OCCUR OVER
THE E LATE WITH SOME MID LVL DRYING FOLLOWING DEPARTING SHRTWV OVER
THE RA MOISTENED LLVLS WITH SW FLOW OFF LK MI.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 328 AM EDT MON JUN 30 2014
A LARGE UPPER TROUGH WILL STILL BE IN PLACE OVER ONTARIO AND THE
NORTH CENTRAL CONUS ON TUESDAY MORNING. A SHORTWAVE ROTATING AROUND
THIS UPPER TROUGH WILL SHIFT THROUGH THE UPPER GREAT LAKES REGION
TONIGHT AND BE PULLING NORTHEAST OUT OF THE AREA. EXPECT ANY
CONVECTION ASSOCIATED WITH THIS SHORTWAVE AND LOW CENTER TO QUICKLY
BE MOVING NORTHEAST THROUGH ONTARIO ON TUESDAY MORNING. A COLD FRONT
STRETCHING SOUTHEAST FROM THE LOW IN ONTARIO WILL TRACK ACROSS THE
UPPER GREAT LAKES REGION TUESDAY AFTERNOON AND NIGHT...LEADING TO
ANOTHER OPPORTUNITY FOR SHOWERS AND MAYBE A FEW THUNDERSTORMS.
EXPECT THE BULK OF THE SHOWER COVERAGE TO DEVELOP OVER THE LAND
AREAS AROUND NOON ON TUESDAY AND SPREAD IN COVERAGE THROUGH THE
AFTERNOON HOURS. THINK THE BEST COVERAGE WILL BE OVER THE
EAST/SOUTHEAST HALF OF UPPER MICHIGAN...ESPECIALLY
ALGER/SCHOOLCRAFT/LUCE COUNTIES WHERE THERE WILL BE SOME HELP FROM
CONVERGENCE OFF LAKE SUPERIOR. WILL CONTINUE TO SHOW HIGH CHANCE OR
LOW END LIKELY VALUES IN THOSE AREAS. FARTHER TO THE WEST...COVERAGE
IS A LITTLE MORE UNCERTAIN DUE TO INDICATIONS OF A WEAK SURFACE
TROUGH SHIFTING THROUGH DURING THE DAY. THIS WILL SHIFT WINDS A
LITTLE MORE WESTERLY (OR EVEN NORTHWESTERLY) AND BRING IN MORE
STABLE AIR FROM LAKE SUPERIOR. THINK THAT WILL KEEP MUCH OF THE
KEWEENAW PENINSULA DRY AND WILL HOLD ONTO SLIGHT OR LOW CHANCES FOR
THE REST OF THE WESTERN HALF OF UPPER MICHIGAN. MID LEVEL LAPSE
RATES ARE ONLY AROUND 5-6 C/KM...HELPING TO LIMIT THUNDER POTENTIAL
AND KEEPING ML CAPES GENERALLY BELOW 200 J/KG. THUS...WILL CONTINUE
TO KEEP THUNDER CHANCES CAPPED AT SLIGHT CHANCES (ALTHOUGH WITH THE
LATEST TRENDS THAT MAY BE GENEROUS). IN ADDITION...IT WILL BE BREEZY
OVER THE KEWEENAW ON TUESDAY. A TIGHT PRESSURE GRADIENT AND STRONGER
WINDS ALOFT (950-925MB WINDS OF 30-35KTS) WILL LEAD TO GUSTS
AROUND 30KTS OVER THE HIGHER TERRAIN LOCATIONS...ALTHOUGH THE MARINE
LAYER MAY TRY TO HOLD SOME OF THE WINDS AT BAY NEAR THE SHORELINE.
AS THE COLD FRONT SHIFTS THROUGH LATE TUESDAY AFTERNOON AND
EVENING...A PERIOD OF ABUNDANT LOW LEVEL MOISTURE AND NORTHWEST FLOW
WILL DEVELOP OVER THE AREA AND LINGER INTO THE OVERNIGHT HOURS. WITH
THE FAVORABLE UPSLOPE FLOW...THINK THE BEST OPPORTUNITY FOR SHOWERS
WILL BE IN THE NORTHWEST WIND FAVORED LOCATIONS IN THE NW HALF OF
UPPER MICHIGAN. DON/T EXPECT THE AMOUNTS TO BE ANYTHING TOO
IMPRESSIVE...A FEW HUNDREDTHS...BUT WILL SHOW CHANCE POPS IN THE
HIGHER TERRAIN FROM GOGEBIC COUNTY THROUGH THE KEWEENAW AND ALSO
HIGHER TERRAIN OF BARAGA AND WESTERN MARQUETTE COUNTY. EXPECT
THESE SHOWERS TO CUT OUT FAIRLY QUICKLY AROUND DAYBREAK...AS MUCH
DRIER AIR SURGES SOUTHEAST INTO THE AREA. THIS WILL LEAD TO
DECREASING CLOUDS FROM NW TO SE ON WEDNESDAY MORNING AND EXPECT THE
AFTERNOON TO BE SUNNY FOR ALL BUT THE SOUTH CENTRAL (WHERE THERE
COULD BE SOME LINGERING DIURNAL CU). WITH THE NORTHWEST WINDS ON
WEDNESDAY...THERE MAY BE AN ELEVATED SWIM RISK FOR ALGER COUNTY
BEACHES. BUT WITH TEMPERATURES STRUGGLING TO GET OUT OF THE
50S...THE AMOUNT OF SWIMMERS WILL BE LIMITED IN THE LOW 40 DEGREE
WATER TEMPERATURES. ELSEWHERE...HIGHS WILL BE WELL BELOW NORMAL AND
IN THE 60S.
HIGH PRESSURE DEVELOPING OVER THE NORTHERN/CENTRAL PLAINS ON
WEDNESDAY WILL SHIFT A RIDGE EAST OVER THE UPPER GREAT LAKES REGION
WEDNESDAY AFTERNOON AND NIGHT. THIS RIDGE WILL STAY IN PLACE
THROUGH THE REST OF THE WORK WEEK...AS THE HIGH SHIFTS THROUGH THE
GREAT LAKES REGION AND THEN INTO THE MID ATLANTIC STATES ON
SATURDAY. THERE SHOULD BE COOLER AND GENERALLY CLEAR CONDITIONS
DURING THIS PERIOD...ALTHOUGH A WEAK SHORTWAVE MAY LEAD TO SOME
CLOUDS ON THURSDAY. EXPECT THE LOWEST LOW TEMPERATURES ON WEDNESDAY
NIGHT...WITH GOOD RADIATIONAL COOLING UNDER CLEAR SKIES...LIGHT
WINDS...AND PWATS AROUND 40 PERCENT OF NORMAL. LIKED THE TREND
SHOWN BY THE PREVIOUS SHIFT (TOWARDS THE BETTER PERFORMING MEX
GUIDANCE ON RADIATIONAL COOLING NIGHTS) AND WILL CONTINUE THAT IDEA.
THAT GIVES LOWS FOR SOME OF THE COLD SPOTS OUT WEST IN THE LOWER 40S
AND UPPER 30S. SHOULD SEE GRADUALLY WARMING HIGHS/LOWS FOR THE REST
OF THE WORK WEEK AND THE 4TH OF JULY STILL LOOKS TO BE A GREAT DAY
FOR OUTDOOR ACTIVITIES. HIGHS WILL BE CLOSE TO NORMAL (70S) UNDER
MOSTLY SUNNY SKIES AND GENERALLY LIGHT WINDS.
HEADING INTO THE WEEKEND...MODELS ARE CONTINUING TO STRUGGLE WITH A
POTENTIAL SHORTWAVE MOVING THROUGH THE NEARLY ZONAL FLOW. THAT IS
TO BE EXPECTED AND LEADS TO LOW CONFIDENCE FOR FRIDAY NIGHT INTO
SATURDAY. WILL SHOW GENERALLY SLIGHT CHANCES INCREASING OVER THE
WESTERN HALF OF THE CWA DURING THIS PERIOD...WITH THE DRY AIR FROM
THE HIGH KEEPING THE EAST DRY. THE INCREASING SOUTHERLY FLOW OVER
THE AREA THIS WEEKEND WITH THE HIGH SHIFTING TO THE SOUTHEAST WILL
LEAD TO AN INCREASE IN TEMPS TO MORE NORMAL OR SLIGHTLY ABOVE
NORMAL VALUES AND ALSO PRODUCE MORE HUMID CONDITIONS. SUNDAY VARIES
TOO...SO WILL GO WITH A CONSENSUS OF THE MODELS AND LEADS TO POPS
SIMILAR TO CLIMO.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 141 PM EDT MON JUN 30 2014
VFR CONDITIONS DOMINATE INTO LATE AFTN. GUSTY WINDS ARE BECOMING THE
MAIN ISSUE WITH GUSTS ALREADY OBSERVED WELL OVER 30 KTS AT KIWD AND
KCMX. EXPECT GUSTS OVER 35 KTS AT TIMES THIS AFTN. A DISTURBANCE
LIFTING ENE ACROSS THE WESTERN GREAT LAKES AND INCREASING MOISTURE
COULD RESULT IN SHRA AND POSSIBLE TSRA AT KSAW THIS EVENING. BEST
INSTABILITY REMAINS SOUTH THOUGH...SO LEFT TSRA MENTION OUT OF KSAW
TAF ATTM. SEEMS THAT KIWD AND KCMX WILL BE ON EDGE OF BETTER CHANCE
FOR SHRA. SHRA END AT KSAW AROUND MIDNIGHT...AND WITH THE DRYING
ALOFT FOLLOWS THE DEPARTING DISTURBANCE...SOME FOG/LO CLDS AND IFR
CONDITIONS MAY DVLP AT SAW OVER THE RA MOISTENED LLVLS IN THE
PRESENCE OF NOCTURNAL COOLING. MORE LLVL MSTR WRAPPING INTO THE WRN
U.P. IN A CYC...UPSLOPE WLY FLOW IS LIKELY TO BRING SOME MVFR CIGS
TO ALL THE TAF SITES ON TUESDAY MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 328 AM EDT MON JUN 30 2014
A STRONG LOW PRESSURE SYSTEM NEAR LAKE WINNIPEG WILL GRADUALLY
SHIFT EAST ACROSS ONTARIO TODAY AND TONIGHT...BEFORE MERGING WITH A
SECONDARY LOW NEAR JAMES BAY ON TUESDAY. EXPECT SOUTH TO
SOUTHWESTERLY WINDS DURING THIS PERIOD...BUT THE MARINE LAYER
SHOULD KEEP WINDS BELOW 25KTS. WARM AND HUMID AIR MOVING OVER LAKE
SUPERIOR WILL CONTINUE TO BRING THE OPPORTUNITY FOR FOG...WITH THE
BEST CHANCE OF LOCALLY DENSE FOG OVER THE NORTHERN HALF OF LAKE
SUPERIOR. A COLD FRONT WILL MOVE SOUTHEAST ACROSS LAKE SUPERIOR ON
TUESDAY NIGHT AND SHIFT WINDS TO THE WEST-NORTHWEST. THIS WILL ALSO
BRING AN END TO THE FOG POTENTIAL AS COOLER AND DRIER AIR MOVES
INTO THE AREA. A HIGH PRESSURE RIDGE WILL DEVELOP OVER LAKE
SUPERIOR ON WEDNESDAY AFTERNOON AND REMAIN THROUGH SATURDAY AS THE
PARENT HIGH SHIFTS EAST FROM THE PLAINS STATES TO THE MID ATLANTIC
STATES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...JLA
MARINE...SRF
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
103 PM EDT MON JUN 30 2014
.AVIATION...
//DISCUSSION...
SATELLITE PICTURE SHOWS TSRA ACTIVITY OVER IOWA SLATED TO TRACK
ACROSS THE MIDWEST AND AFFECT THE SE MI TERMINALS AROUND 03-09Z.
THIS WILL BRING THE THREAT FOR SEVERE IN THE 03-10Z TIMEFRAME WITH
DAMAGING WINDS BEING THE MAIN THREAT. DO NOT SEE ANY RESTRICTIONS
TO VSBY OR CIG BEFORE THAT TIME. THE THREAT FOR CONVECTIVE
ACTIVITY LATE THIS AFTERNOON IS TOO SLIM TO MENTION IN TAFS.
//DTW THRESHOLD THREATS...
* MEDIUM CONFIDENCE IN THUNDERSTORMS AND TIMING TONIGHT.
* MEDIUM CONFIDENCE IN CEILINGS AOB 5000 FEET TONIGHT.
&&
.PREV DISCUSSION...ISSUED 1115 AM EDT MON JUN 30 2014
UPDATE...
STILL TRACKING THE THREAT FOR SEVERE WEATHER THROUGH THIS
EVENING AND TONIGHT. 12Z OBS AND MODEL OUTPUT CONTINUE THE
PREVIOUS TRAIN OF THOUGHT WITH HIGH INSTABILITY THIS AFTERNOON AND
EVENING THAT LACK A FORCING MECHANISM. AFTER MIDNIGHT...MCS RACING
ACROSS LAKE MICHIGAN WILL TAP INTO SLIGHTLY LESS UNSTABLE AIRMASS.
BULK SHEER INCREASES LATE NIGHT AS WELL WITH 0-6KM VALUES NEAR
60KT IN THE SAGINAW VALLEY. 12Z NAM OUTPUT SPORTED A 5500 J/KG POWDER
KEG AT 21Z IN KLAN...BUT BASED OFF OF A BRAVADO 86/76 SURFACE
PARCEL. MOST LIKELY SCENARIO WILL BE WIDELY SCATTERED SHOWERS IN
THE 20-00Z TIME FRAME WITH ORGANIZED BOW ECHO/DERECHO MOVING
THROUGH THE AREA 04-10Z. SUPPORT FOR DERECHO THREAT INCLUDES RIGHT
REAR 115KT JET SUPPORT...LLJ OF 40-50KT AT H85 AND 55-65KT AT H5.
REMNANT JUICY CAPE OF 2500 J/KG AND DCAPE NEAR 2000 J/KG WILL BE
SUPPORTIVE OF ACCELERATING COLD POOLS. HRRR ...ARW...AND NMM HI-
RES MODELS ALL POINT TO A SIMILAR SOLUTION TONIGHT WITH DIFFERING
STRENGTH AND LOCATION OF MULTICELL LINE/CLUSTERS MOVING THROUGH
THE CWA.
PREV DISCUSSION...ISSUED 708 AM EDT MON JUN 30 2014
UPDATE...
UPDATED TO REMOVE EARLY MORNING RAIN CHANCES AS OVERNIGHT MCS TO
THE WEST HAS ALL BUT DISSIPATED NORTH OF THE MICHIGAN AND INDIANA
STATE LINE.
WITH MODERATELY UNSTABLE CONDITIONS DEVELOPING TODAY AS DEW POINTS
HOLD CLOSE TO 70 AND TEMPERATURES APPROACH 90...EXPECT ISOLATED TO
SCATTERED STORMS LATE THIS AFTERNOON. HOWEVER...IT STILL APPEARS
THE MOST IMPRESSIVE ACTIVITY WILL TRACK IN FROM THE WEST THIS
EVENING INTO THE OVERNIGHT HOURS AS A STRONG SHORTWAVE PIVOTS INTO
THE GREAT LAKES. TIMING OF THE CONVECTIVE SYSTEM ASSOCIATED WITH
THIS FEATURE REMAINS IN QUESTION. THE LATER IT ARRIVES...THE LESS
ORGANIZED/SEVERE THE CONVECTION WILL BE.
PREV DISCUSSION...ISSUED 316 AM EDT MON JUN 30 2014
SHORT TERM...TODAY AND TONIGHT
WHILE NORTHERN EXTENT OF THE MCS EXTENDING FROM LAKE MICHIGAN
SOUTHWEST INTO NORTHERN ILLINOIS HAS BECOME LESS ORGANIZED OVER THE
PAST 3 OR 4 HOURS...AND MODELS SUGGEST THIS TREND WILL CONTINUE
INTO THE MORNING AS THE ACTIVITY OUTRUNS ITS SUPPORTING LOW LEVEL
JET...IT APPEARS SOME OF THIS CONVECTION WILL MOVE INTO THE CWA
EARLY THIS MORNING BEFORE FADING DURING THE CLIMATOLOGICAL MINIMUM
FOR CONVECTION AFTER SUNRISE. WILL REDRAW POPS TO ADJUST FOR THESE
TRENDS.
OTHERWISE...WIDELY SCATTERED/SCATTERED CONVECTION WILL MOST LIKELY
RE-DEVELOP DURING THE AFTERNOON ALONG OUTFLOW FROM THIS SYSTEM AND
ALSO IMMEDIATELY ALONG LAKE/LAND INTERFACE. THIS ACTIVITY SHOULD
REMAIN RATHER DISORGANIZED WITH SPARSE COVERAGE GIVEN LACK OF UPPER
LEVEL SUPPORT AND LOW LEVEL FORCING.
CONDITIONS WILL CHANGE THIS EVENING INTO TONIGHT AS SIGNIFICANT
UPPER LEVEL SUPPORT ENCROACHES ON THE AREA AS VIGOROUS SHORTWAVE
PIVOTS THROUGH THE UPPER MIDWEST INTO THE GREAT LAKES AROUND UPPER
LOW PRESSURE STILL CENTERED NEAR LAKE WINNIPEG. THUNDERSTORMS WILL
BE ESPECIALLY IMPRESSIVE TO OUR WEST AS THE AFFECTS OF THIS WAVE
COINCIDE WITH PEAK DAYTIME HEATING DURING THE AFTERNOON/EARLY
EVENING. THAT SAID...EXPECT THE LARGE CONVECTIVE SYSTEM THAT DOES
EVOLVE OUT OF INITIAL SEVERE CONVECTION TO RACE INTO THE AREA BY
EVENING...PROBABLY FASTER THAN MODELS SUGGEST AS EXPANDING SYSTEM
DEVELOPS A SIGNIFICANT COLD POOL WITH TIME. INSTABILITY WILL STILL
BE RATHER IMPRESSIVE DURING THE MID/LATE EVENING GIVEN THE INFLUX OF
WARM/MOIST AIR INTO THE AREA. WILL MAINTAIN GENERALLY CHANCE POPS
DURING THE AFTERNOON/EARLY EVENING WITH LIKELY FROM MID/LATE EVENING
INTO THE OVERNIGHT HOURS.
WITH SBCAPES ON THE ORDER OF 3000 J/KG BY LATE IN THE DAY AND 0-6KM
BULK SHEAR INCREASING FROM 25-35 KTS TO AROUND 45 KTS DURING THE
COURSE OF THE EVENING...EXPECT SEVERE WEATHER TO BE A DISTINCT
POSSIBILITY. THE EXTENT/MAGNITUDE...AS IS OFTEN THE CASE...WILL BE
DICTATED BY HOW CURRENT CONVECTION INFLUENCES ATMOSPHERIC CONDITIONS
AND HENCE DEVELOPMENT/EVOLUTION OF MAIN MCS IN QUESTION LATER TODAY.
WITH ANY LUCK...THE ARRIVAL INTO THE AREA SEVERAL HOURS AFTER PEAK
HEATING WILL ALLOW FOR SOME MODEST WEAKENING OF OVERALL CONVECTIVE
SYSTEM OVER SOUTHEAST LOWER MICHIGAN.
LONG TERM...
LONGWAVE PATTERN OVER NORTH AMERICA WILL BUCKLE EARLY IN THE LONG
TERM PERIOD IN RESPONSE TO DEEPENING LOW APPROACHING THE PACIFIC
NORTHWEST. AS THIS OCCURS, THE STRONG CLOSED LOW OVER MANITOBA WILL
TRANSITION TO AN OPEN WAVE AND BE SWEPT NORTHEAST AS LONGWAVE
TROUGHING AMPLIFIES OVER THE GREAT LAKES, BRINGING MARKEDLY COOLER
TEMPERATURES BY LATE WEEK. OCCASIONAL LOW AMPLITUDE WAVES EMBEDDED
IN THE FLOW WILL BRING EPISODIC CLOUD COVER OR SHOWER CHANCES BEFORE
HIGH PRESSURE BUILDS IN FROM THURSDAY ONWARD.
COLD FRONT WHICH WILL PROVIDE THE FOCUS FOR THIS AFTERNOON`S SEVERE
CONVECTION OVER THE CENTRAL UNITED STATES IS PROGGED TO BE BISECTING
THE CWA BY 12Z TUESDAY MORNING. THE PRESENCE OF A WELL-DEFINED FRONT
AND INCREASING DIURNAL HEATING ALONE WARRANTS LOW CHANCE POPS BEFORE
THE FRONT EXITS TO THE EAST BY AROUND 18Z. IN REALITY, THE REGIONAL
ENVIRONMENT WILL HAVE UNDERGONE POTENTIALLY SIGNIFICANT MODIFICATION
COURTESY OF TODAY/TONIGHT`S WIDESPREAD CONVECTIVE EPISODE. COULD SEE
ANYTHING RANGING FROM CONVECTIVE REMNANTS BEING SWEPT INTO THE CWA
WITHIN DEVELOPING SOUTHWEST FLOW TO DRY CONDITIONS OWING TO
SUBSIDENCE IN THE WAKE OF CONVECTION. MOST PRUDENT PLAY AT THIS TIME
APPEARS TO BE FOR 30-40 TYPE POPS ALONG/AHEAD OF THE FRONTAL ZONE.
DRIER AND MORE STABLE AIR WILL FILTER IN FOR THE REMAINDER OF THE
DAY, ENDING PRECIP CHANCES BY AFTERNOON AND CAPPING HIGHS IN THE
LOW/MID 80S.
FAIRLY POTENT SHORTWAVE IS THEN FORECAST TO SWING THROUGH THE GREAT
LAKES DURING THE DAYTIME HOURS ON WEDNESDAY. INSTABILITY WILL BE
QUITE LIMITED, PERHAPS 500 J/KG, AS DEWPOINTS FALL TO AROUND 60F.
HOWEVER, SUPERPOSITION OF DYNAMIC FORCING WITH ONGOING LIGHT COLD
ADVECTION IS EXPECTED TO PROVIDE A FAVORABLE ENVIRONMENT FOR
AGGRESSIVE EXPANSION OF DIURNAL CLOUD COVER AS WELL AS SCATTERED
SHOWERS IN ADVANCE OF THE WAVE.
SECONDARY WAVE OF COLD ADVECTION WILL GET UNDERWAY WITH THE PASSAGE
OF WEDNESDAY`S WAVE. BY THURSDAY MORNING, H85 TEMPERATURES ARE
PROGGED TO BE SOLIDLY IN THE SINGLE DIGITS. OVERNIGHT LOW
TEMPERATURES WILL BE DEPENDENT ON CLOUD COVER, OF WHICH THERE SHOULD
BE PLENTY GIVEN ONGOING BOUNDARY LAYER MIXING AND CONTINUED CYCLONIC
FLOW ALOFT. THUS, SIDED WITH THE CONSENSUS FOR WEDNESDAY NIGHT WHICH
SHOWS MOST SPOTS DIPPING DOWN INTO 50S BY THURSDAY MORNING...PERHAPS
UPPER 40S IN THE SAGINAW VALLEY.
TEMPERATURE RECOVERY WILL BE LIMITED ON THURSDAY OWING THE POSITION
OF THE THERMAL TROUGH DIRECTLY OVERHEAD AND THE POTENTIAL FOR
ANOTHER ROUND OF HEALTHY BOUNDARY LAYER CLOUD DEVELOPMENT. EXPECT
HIGHS TO REACH THE LOW 70S...UPPER 60S IN THE THUMB. HIGH PRESSURE
WILL THEN SETTLE IN FOR THE REMAINDER OF THE LONG TERM PERIOD AND
GRADUAL AIRMASS RECOVERY WILL LEAD TO SLOWLY RISING TEMPS THROUGH
THE WEEKEND.
MARINE...
LIGHT TO MODERATE SOUTHWEST FLOW WILL PERSIST THROUGH MIDWEEK UNTIL
A COLD FRONT TURNS WINDS MORE TO THE NORTHWEST AND ALLOWS COOLER AIR
TO OVERSPREAD AREA WATERS. WITH NO NOTEWORTHY WIND EVENTS ON THE
HORIZON...THE PRIMARY CONCERN WILL BE THUNDERSTORM ACTIVITY WHICH
WILL PLAGUE THE AREA THROUGH LATE TONIGHT. ALTHOUGH COVERAGE OF
STORMS OVER THE WATERS IS UNCERTAIN...A FEW SEVERE STORMS IS NOT OUT
OF THE QUESTION. HIGH PRESSURE WILL BUILD ACROSS THE GREAT LAKES BY
THE END OF THE WEEK.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....MM
UPDATE.......MM
SHORT TERM...DG
LONG TERM....JVC
MARINE.......JVC
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
320 PM CDT Mon Jun 30 2014
.SHORT TERM: (Through Late Tonight)
Issued at 318 PM CDT Mon Jun 30 2014
Some places reaching heat indices of 100-105 this afternoon due to
warm temperatures around 90 degrees and very high surface dew points
in the middle to upper 70s. The heat advisory will continue in
effect for the St Louis metro area into the early evening hours.
With a capped atmosphere and little if any forcing, not getting the
typical diurnal isolated to scattered showers/storms this afternoon
across our forecast area. Convection is expected to continue to
develop across IA and northwest MO and eventually shift
southeastward into northeast MO and west central IL early this
evening as a shortwave and cold front along with outflow boundaries
ahead of the front approach and help to break the cap and provide a
surface focus for convection. Due to the extreme instability along
with sufficient low-mid level wind shear, damaging winds along with
large hail and isolated tornadoes are possible with these storms
this evening across northeast MO and west central IL. Went with a
compromise between the faster NCEP 4 km WRF and the slower HRRR
model for the precipitation forecast. A broken line of convection
is expected to drop southeastward through northeast MO and west
central IL early this evening. This line of convection should
gradually weaken later this evening and into the overnight hours as
it moves into central MO and southwest IL, although maybe not as
fast as the HRRR model depicts. Slightly cooler low temperatures
are expected tonight compared to last night across northeast MO and
west central IL behind the southeastward moving cold front.
GKS
.LONG TERM: (Tuesday through Next Monday)
Issued at 318 PM CDT Mon Jun 30 2014
(Tuesday)
Cooler day is in store for Tuesday as initial cold front should clear the
southern extent of the CWA by Tuesday morning. Drier air with dewpoints
filtering down into the 60s is also expected. Chances of showers and storms
are forecast to be confined to southeastern Missouri where a shortwave
will round the base of an amplifying longwave trough and interact with sagging
frontal boundary/baroclinic zone. Rest of forecast area is expected to remain
dry with highs about 3-7F cooler than today but it will feel quite a bit
better than today due to dewpoints also lowering.
Secondary cold front should slip by the area overnight Tuesday night and
is expected to pass through dry. Main impact this frontal boundary will
bring is that it will usher in the start of some unseasonably cool and dry
weather.
(Wednesday - Friday)
The Wednesday through Friday time period will be characterized by much
cooler than normal temperatures accompanied by unseasonably low dewpoints.
Look for temperatures to be some 10 to near 15 degrees below normal day
and night. This results in highs in the 70s with lows in the 50s...not too
unlike what was observed early in July of last year. Lows on Thursday
morning...and to a lesser degree Friday morning...may even approach record
minimums for the date. All in all...a beautiful and pleasant 4th of July
looks to be in store for the bi-state region.
(Saturday - Monday)
Surface ridge and associated anticyclone will slowly move off to the east
with upper-level heights also on the rise. This will result in a
moderation in temperatures as well as a climb in dewpoints/humidity levels.
The process will be slow and gradual however leading to comfortable levels
of temps/humidities thanks to persistent dry/cool low-level flow around
Great Lakes. More typical summertime temperatures and dewpoints look to
hold off until Monday.
Next chance of precipitation in the form of showers and thunderstorms will
be Saturday night through Sunday as a shortwave travels around the periphery
of upper-level high across the desert southwest.
Gosselin
&&
.AVIATION: (For the 18z TAFs through 18z Tuesday Afternoon)
Issued at 1108 AM CDT Mon Jun 30 2014
Atmosphere should be too capped for convection this afternoon,
but there will still be scattered diurnal cumulus clouds.
Thunderstorms, possibly severe should impact UIN early this evening
as an upper level disturbance and cold front approaches. This
convection should gradually weaken as it moves southeastward into
COU and the St Louis metro area late this evening and overnight.
The cold front will move through UIN around 06z Tuesday and
through STL around 12z Tuesday as it weakens. The s-swly surface
wind will veer around to a w-nwly direction after fropa.
Specifics for KSTL: Scattered diurnal cumulus clouds this
afternoon. Weakening convection should drop southeastward into STL
late this evening and overnight as a weakening cold front
approaches. S-swly surface wind will become gusty this afternoon.
The surface wind will veer around to a w-nwly direction Tuesday
morning after fropa.
GKS
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 73 87 66 78 / 40 10 10 10
Quincy 67 83 60 71 / 60 10 10 10
Columbia 71 83 60 75 / 40 10 5 5
Jefferson City 72 84 62 76 / 50 20 10 5
Salem 73 86 65 79 / 30 20 20 10
Farmington 72 86 64 80 / 30 30 20 5
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...HEAT ADVISORY until 8 PM CDT this evening FOR St. Charles MO-St.
Louis City MO-St. Louis MO.
IL...HEAT ADVISORY until 8 PM CDT this evening FOR Madison IL-St.
Clair IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
431 PM EDT MON JUN 30 2014
.SYNOPSIS...
A WARM AND HUMID AIR MASS WILL REMAIN IN PLACE ACROSS THE NORTH
COUNTRY TONIGHT INTO MIDWEEK. THE WARMEST DAY WILL LIKELY BE
TUESDAY WITH HEAT INDICES IN THE MID TO UPPER 90S...WITH LOWS IN
THE 60S TO LOW 70S PROVIDING LITTLE RELIEF AT NIGHT. AN INCREASING
THREAT OF SHOWERS AND THUNDERSTORMS THROUGH MIDWEEK. SOME STORMS
COULD BE STRONG ON TUESDAY FROM THE CHAMPLAIN VALLEY WEST...WITH
LINGERING STRONG STORMS POSSIBLE ON WEDNESDAY EAST OF THE
CHAMPLAIN VALLEY. COOLER AND DRIER WEATHER THEN RETURNS BY LATE
WEEK.
&&
.NEAR TERM /UNTIL 7 AM TUESDAY MORNING/...
AS OF 405 PM EDT MONDAY...LATE-AFTERNOON VISIBLE SATELLITE AND
REGIONAL RADAR SHOWS AN AREA OF ISOLATED TO WIDELY SCATTERED
SHOWERS/POSSIBLE THUNDER ACROSS ESSEX AND CLINTON COUNTIES IN NEW
YORK. THESE SHOWERS AND STORMS ARE FORMING IN AN ENVIRONMENT
THAT`S SLIGHTLY UNSTABLE PER RAP STABILITY ANALYSES (LI`S OF -2 TO
-3 AND SFC- BASED CAPES OF 500 TO 900 J/KG). APPEARS THAT
CHAMPLAIN VALLEY CONVERGENCE ZONE PROVIDING ENOUGH LIFT TO GET
THESE TO GO. THESE WILL SLOWLY DRIFT EAST AND BEGIN TO WEAKEN
THROUGH SUNSET AS THEY MOVE OFF THAT ZONE OF LOW-LEVEL
CONVERGENCE. ADDITIONAL CONVECTION IS EVIDENT ACROSS
ONTARIO...THOUGH DEVELOPING IN A REGIME OF STRONGER MID-LEVEL
SWLYS/MEAN SW STORM MOTION VECTORS. THUS...FEEL THIS ACTIVITY
WOULD LIFT NORTHWEST OF THE NORTH COUNTRY AND HAVE GONE WITH A DRY
FORECAST AFTER MIDNIGHT.
IT WILL BE A WARM AND MUGGY NIGHT WITH DEWPOINTS HAVING CLIMBED
INTO THE MID 60S TO LOW 70S. IT MIGHT BE SLIGHTLY COOLER THAN LAST
NIGHT DUE TO A LITTLE LESS CLOUDS AND HIGHS BEING A COUPLE DEGREES
COOLER THAN YESTERDAY...BUT NOT BY MUCH. I`VE OFFERED LOWS IN THE
60S...WITH UPPER 60S TO AROUND 70 IN THE VALLEYS UNDER A LIGHT
SOUTH/SOUTHWEST WIND.
&&
.SHORT TERM /7 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
AS OF 405 PM EDT MONDAY...ACTIVE COUPLE DAYS IN STORE WITH SEVERAL
ISSUES TO ADDRESS FOR TUESDAY INTO WEDNESDAY. THIS INCLUDES
INCREASING HEAT AND HUMIDITY AND POSSIBLE STRONG TO SEVERE
THUNDERSTORMS TUESDAY...AND POSSIBLE LINGERING THREAT FOR STRONG
STORMS ON WEDNESDAY.
ON TUESDAY: LOOKING AT A HAZY HOT AND HUMID DAY...AND FOR MANY IT
WILL BE THE FIRST DAY THIS SUMMER WHERE THE COMBINATION OF HEAT AND
HUMIDITY WILL MAKE IT FEEL UNCOMFORTABLE. WARM AIR ADVECTION
TAKES PLACE AT LOW-LEVELS BRINGING IN 925 MB TEMPS OF +23 TO +25C.
THAT WILL RESULT IN DAYTIME HIGHS IN THE UPPER 80S TO THE LOWER
90S UNDER MOSTLY SUNNY SKIES. WITH UPPER 60S TO LOW 70S DEWPOINTS
ALREADY IN PLACE...APPARENT TEMPERATURES WILL REACH THE MID TO
UPPER 90S. THIS ISN`T QUITE HEAT ADVISORY CRITERIA SO I HAVEN`T
ISSUED ANY HEAT HEADLINES...BUT THE APPARENT TEMPS ARE HIGH ENOUGH
TO MAKE IT FEEL A BIT OPPRESSIVE. NIGHTTIME LOWS WILL ALSO BE
QUITE WARM AS WELL WITH UPPER 60S TO LOWER 70S FORECAST. FOR NOW
WILL ONLY MENTION HEAT CONCERNS IN THE HWO.
TUESDAY MORNING AND EARLY AFTERNOON WILL BE CAPPED TO CONVECTION.
THE INCREASING THERMAL ADVECTION BRINGS IN 700 MB TEMPS OF NEAR
+10C AND GUIDANCE SHOW NO EVIDENT MID-LEVEL SHORTWAVE OR FRONTAL
FORCING TO BREAK THIS CAP. THAT LOOKS TO CHANGE BY MID AFTERNOON AS
LEADING EDGE OF CYCLONIC MID-LEVEL FLOW TIED TO THE SLOW-MOVING
UPPER MIDWEST LOW INTRUDES INTO THE SAINT LAWRENCE VALLEY AND THE
ADIRONDACKS. MODERATE INSTABILITY WILL ALREADY HAVE DEVELOPED GIVEN
THE WARM TEMPERATURES (UP TO AROUND 2000 J/KG OF CAPE). PLENTY OF
MOISTURE AVAILABLE WITH PWATS AROUND 1.5-1.9 INCHES. WIND FIELDS
WILL BE INCREASING AS WELL WITH 500 MB WINDS INCREASING TO NEAR 40
KTS BY TUESDAY AFTERNOON. INCREASING LOW AND MID-LEVEL WINDS
PRODUCES 0-6KM VERTICAL SHEAR MAGNITUDES OF 35-40 KTS...SUPPORTIVE
OF SUSTAINING UPDRAFTS. THUS A RISK FOR STRONG TO SEVERE
THUNDERSTORMS WILL EXIST LATE IN THE DAY INTO THE MID-EVENING
HOURS WITH THE PRIMARY THREAT AREA BEING FROM THE NORTH CHAMPLAIN
VALLEY WESTWARD. CONVECTIVE MODE WOULD LIKELY TAKE THE FORM OF
LINE SEGMENTS...AN INDICATION OFFERED BY SOME OF THE HI- RES
CONVECTION-ALLOWING MODELS. THIS MATCHES UP WELL WITH SPC`S
AFTERNOON DAY 2 CONVECTIVE OUTLOOK. THERE`S SOME QUESTION HOW FAR
EAST THE STRONG TO SEVERE THUNDERSTORMS WILL MAKE IT AS
INSTABILITY WILL BE WANING. FOR NOW I HAVE ADDED ENHANCED WORDING
FOR GUSTY WINDS AND HEAVY RAINFALL FROM THE NORTHERN CHAMPLAIN
VALLEY TO THE SAINT LAWRENCE VALLEY.
FOR WEDNESDAY: COLD FRONT THAT WILL TRIGGER THE STORMS TUESDAY
IS EXPECTED TO SLOWLY DRIFT EASTWARD. IT`S DIFFICULT TO PINPOINT
EXACT FRONTAL POSITION AS THAT WILL BE AFFECTED TO SOME DEGREE BY
SHOWERS/STORMS TUESDAY EVENING. PLENTY OF CLOUDS WILL LIKELY BE IN
PLACE AHEAD OF THE FRONT...WHICH PLACES SOME QUESTION ON HOW MUCH
INSTABILITY CAN BE PRODUCED. HOWEVER...WIND FIELDS WEDNESDAY WILL
BE MORE THAN SUPPORTIVE OF ORGANIZED THUNDERSTORMS IF ANY CAN
DEVELOP. BASED ON PRESENT INDICATIONS FEEL THE PRIMARY AREA FOR ANY
STRONGER STORMS WOULD BE FROM THE CHAMPLAIN VALLEY
EASTWARD - BUT I WON`T INDICATE ENHANCED WORDING YET UNTIL THERE`S
MORE CLARITY ON THE DEGREE OF INSTABILITY. HAVE GONE WITH HIGH
CHANCE POPS FROM THE CHAMPLAIN VALLEY EAST TAPERING TO
CHANCE/SLIGHT CHANCE WITH WESTWARD EXTENT. STILL QUITE WARM AND
HUMID...BUT CLOUDS WILL KEEP TEMPERATURES DOWN SOMEWHAT. I`VE GONE
WITH HIGHS IN THE MID TO UPPER 80S WITH SLIGHTLY COOLER LOWS IN
THE LOW/MID 60S (A FEW UPPER 60S POSSIBLE CHAMPLAIN VALLEY AND
EAST VT).
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 431 PM EDT MONDAY...FRONTAL SYSTEM WILL BE OVER THE REGION
EARLY THURSDAY. GFS MODEL SHOWING THE BEST INSTABILITY WILL BE
MAINLY OVER EASTERN AND SOUTHERN VERMONT ON THURSDAY...SO HAVE
GONE WITH A MENTION OF SHOWERS AND THUNDERSTORMS IN THESE
LOCATIONS... WITH JUST A CHANCE OF SHOWERS ACROSS THE REMAINDER OF
THE REGION ON THURSDAY. THERE WILL STILL BE A CHANCE FOR SOME
THUNDERSTORMS ACROSS SOUTHEAST VERMONT EARLY THURSDAY NIGHT...WITH
JUST A CHANCE OF RAIN SHOWERS ELSEWHERE.
GFS AND ECMWF MODELS SHOWING SOME DIFFERENCES ON THE FORECAST FOR FRIDAY
...WITH THE GFS MODEL DRY. THE ECMWF MODEL KEEPS A CHANCE FOR SOME
SHOWERS ACROSS THE REGION ON FRIDAY. HAVE GONE WITH THE SUPER-
BLEND POPS FOR FRIDAY AND KEPT IN A CHANCE OF SHOWERS MAINLY OVER VERMONT...AS
FRONTAL SYSTEM WILL BE SLOW TO MOVE EASTWARD AS MODELS SHOWING A
TROPICAL SYSTEM WILL MOVE NORTH ALONG THE EAST COAST AND THEN TURN
OUT TO SEA WELL SOUTH OF NEW ENGLAND.
ECMWF AND GFS MODELS IN GOOD AGREEMENT IN SHOWING A RIDGE OF HIGH
PRESSURE BUILDING EAST FROM THE GREAT LAKES FRIDAY NIGHT AND
REMAINING OVER THE REGION THROUGH MONDAY.
&&
.AVIATION /20Z MONDAY THROUGH SATURDAY/...
THROUGH 18Z TUESDAY...VFR CONDITIONS EXPECTED THROUGH THE PERIOD.
LATEST GUIDANCE SUGGESTING MID LEVEL CLOUDS THAT WERE OVER THE REGION
THIS MORNING AND EARLY THIS AFTERNOON...WITH JUST SOME CUMULUS
CLOUDS AND SOME HIGH THIN CIRRUS CLOUDS EXPECTED. THE CUMULUS
CLOUDS WILL DISSIPATE AROUND 00Z TUESDAY DUE TO THE LOSS OF
DAYTIME SURFACE HEATING. EXPECTING MAINLY CLEAR SKIES OR JUST SOME
HIGH THIN CIRRUS CLOUDS AT TIMES OVERNIGHT TONIGHT. GUIDANCE
HINTING AT SOME FOG LATE TONIGHT...BUT WINDS JUST ABOVE THE
SURFACE ARE FAIRLY STRONG...SO NOT EXPECTING ANY FOG TO DEVELOP
OVERNIGHT AT THIS TIME. SURFACE PRESSURE GRADIENT TO TIGHTEN ACROSS
THE REGION DURING THE DAY ON TUESDAY...SO SOME SOUTHERLY SURFACE
WIND GUSTS AROUND 20 KNOT ARE POSSIBLE FROM 13Z-18Z AND BEYOND ON
TUESDAY.
OUTLOOK 18Z TUESDAY THROUGH SATURDAY...
18Z TUESDAY ONWARD...MAINLY VFR THOUGH WITH A SLOWLY INCREASING
CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH THE PERIOD AS A WEAK
FRONTAL BOUNDARY MOVES INTO THE REGION. MVFR CIGS AND BRIEF IFR
VSBYS POSSIBLE WITH ANY SHOWERS OR THUNDERSTORMS. HIGHEST COVERAGE
DURING AFTERNOON/EARLY EVENING HOURS. RIDGE OF HIGH PRESSURE
BUILDS EAST FROM THE GREAT LAKES BY FRIDAY WITH SHOWER THREAT
DIMINISHING. EXPECTING VFR CONDITIONS UNDER SURFACE HIGH PRESSURE
AREA FRIDAY NIGHT AND SATURDAY.
&&
.EQUIPMENT...
AS OF 156 PM EDT MONDAY...THE AUTOMATED WEATHER OBSERVING SYSTEM
(AWOS) AT THE RUTLAND-SOUTHERN VERMONT REGIONAL AIRPORT (KRUT)
WILL BE OUT OF SERVICE ON TUESDAY, JULY 1, FROM 14Z-18Z (1000 AM
EDT-200 PM EDT) FOR MAINTENANCE.
THE TEMPERATURE/DEW POINT DATA SENSORS AT THE AUTOMATED WEATHER
OBSERVING SYSTEM (AWOS) AT THE NEWPORT STATE AIRPORT IN NEWPORT
VERMONT (KEFK) ARE OUT OF SERVICE AT THIS TIME. THE VERMONT
AGENCY OF TRANSPORTATION HAS INFORMED THE NATIONAL WEATHER SERVICE
IN BURLINGTON THAT PARTS ARE ON BACK ORDER TO FIX THIS, BUT THAT
TEMPERATURE/DEW POINT DATA AT THIS SITE MAY NOT BE RESTORED UNTIL
EARLY SEPTEMBER.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LOCONTO
NEAR TERM...LOCONTO
SHORT TERM...LOCONTO
LONG TERM...WGH
AVIATION...WGH
EQUIPMENT...WGH
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
406 PM EDT MON JUN 30 2014
.SYNOPSIS...
A WARM AND HUMID AIR MASS WILL REMAIN IN PLACE ACROSS THE NORTH
COUNTRY TONIGHT INTO MIDWEEK. THE WARMEST DAY WILL LIKELY BE
TUESDAY WITH HEAT INDICES IN THE MID TO UPPER 90S...WITH LOWS IN
THE 60S TO LOW 70S PROVIDING LITTLE RELIEF AT NIGHT. AN INCREASING
THREAT OF SHOWERS AND THUNDERSTORMS THROUGH MIDWEEK. SOME STORMS
COULD BE STRONG ON TUESDAY FROM THE CHAMPLAIN VALLEY WEST...WITH
LINGERING STRONG STORMS POSSIBLE ON WEDNESDAY EAST OF THE
CHAMPLAIN VALLEY. COOLER AND DRIER WEATHER THEN RETURNS BY LATE
WEEK.
&&
.NEAR TERM /UNTIL 7 AM TUESDAY MORNING/...
AS OF 405 PM EDT MONDAY...LATE-AFTERNOON VISIBLE SATELLITE AND
REGIONAL RADAR SHOWS AN AREA OF ISOLATED TO WIDELY SCATTERED
SHOWERS/POSSIBLE THUNDER ACROSS ESSEX AND CLINTON COUNTIES IN NEW
YORK. THESE SHOWERS AND STORMS ARE FORMING IN AN ENVIRONMENT
THAT`S SLIGHTLY UNSTABLE PER RAP STABILITY ANALYSES (LI`S OF -2 TO
-3 AND SFC- BASED CAPES OF 500 TO 900 J/KG). APPEARS THAT
CHAMPLAIN VALLEY CONVERGENCE ZONE PROVIDING ENOUGH LIFT TO GET
THESE TO GO. THESE WILL SLOWLY DRIFT EAST AND BEGIN TO WEAKEN
THROUGH SUNSET AS THEY MOVE OFF THAT ZONE OF LOW-LEVEL
CONVERGENCE. ADDITIONAL CONVECTION IS EVIDENT ACROSS
ONTARIO...THOUGH DEVELOPING IN A REGIME OF STRONGER MID-LEVEL
SWLYS/MEAN SW STORM MOTION VECTORS. THUS...FEEL THIS ACTIVITY
WOULD LIFT NORTHWEST OF THE NORTH COUNTRY AND HAVE GONE WITH A DRY
FORECAST AFTER MIDNIGHT.
IT WILL BE A WARM AND MUGGY NIGHT WITH DEWPOINTS HAVING CLIMBED
INTO THE MID 60S TO LOW 70S. IT MIGHT BE SLIGHTLY COOLER THAN LAST
NIGHT DUE TO A LITTLE LESS CLOUDS AND HIGHS BEING A COUPLE DEGREES
COOLER THAN YESTERDAY...BUT NOT BY MUCH. I`VE OFFERED LOWS IN THE
60S...WITH UPPER 60S TO AROUND 70 IN THE VALLEYS UNDER A LIGHT
SOUTH/SOUTHWEST WIND.
&&
.SHORT TERM /7 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
AS OF 405 PM EDT MONDAY...ACTIVE COUPLE DAYS IN STORE WITH SEVERAL
ISSUES TO ADDRESS FOR TUESDAY INTO WEDNESDAY. THIS INCLUDES
INCREASING HEAT AND HUMIDITY AND POSSIBLE STRONG TO SEVERE
THUNDERSTORMS TUESDAY...AND POSSIBLE LINGERING THREAT FOR STRONG
STORMS ON WEDNESDAY.
ON TUESDAY: LOOKING AT A HAZY HOT AND HUMID DAY...AND FOR MANY IT
WILL BE THE FIRST DAY THIS SUMMER WHERE THE COMBINATION OF HEAT AND
HUMIDITY WILL MAKE IT FEEL UNCOMFORTABLE. WARM AIR ADVECTION
TAKES PLACE AT LOW-LEVELS BRINGING IN 925 MB TEMPS OF +23 TO +25C.
THAT WILL RESULT IN DAYTIME HIGHS IN THE UPPER 80S TO THE LOWER
90S UNDER MOSTLY SUNNY SKIES. WITH UPPER 60S TO LOW 70S DEWPOINTS
ALREADY IN PLACE...APPARENT TEMPERATURES WILL REACH THE MID TO
UPPER 90S. THIS ISN`T QUITE HEAT ADVISORY CRITERIA SO I HAVEN`T
ISSUED ANY HEAT HEADLINES...BUT THE APPARENT TEMPS ARE HIGH ENOUGH
TO MAKE IT FEEL A BIT OPPRESSIVE. NIGHTTIME LOWS WILL ALSO BE
QUITE WARM AS WELL WITH UPPER 60S TO LOWER 70S FORECAST. FOR NOW
WILL ONLY MENTION HEAT CONCERNS IN THE HWO.
TUESDAY MORNING AND EARLY AFTERNOON WILL BE CAPPED TO CONVECTION.
THE INCREASING THERMAL ADVECTION BRINGS IN 700 MB TEMPS OF NEAR
+10C AND GUIDANCE SHOW NO EVIDENT MID-LEVEL SHORTWAVE OR FRONTAL
FORCING TO BREAK THIS CAP. THAT LOOKS TO CHANGE BY MID AFTERNOON AS
LEADING EDGE OF CYCLONIC MID-LEVEL FLOW TIED TO THE SLOW-MOVING
UPPER MIDWEST LOW INTRUDES INTO THE SAINT LAWRENCE VALLEY AND THE
ADIRONDACKS. MODERATE INSTABILITY WILL ALREADY HAVE DEVELOPED GIVEN
THE WARM TEMPERATURES (UP TO AROUND 2000 J/KG OF CAPE). PLENTY OF
MOISTURE AVAILABLE WITH PWATS AROUND 1.5-1.9 INCHES. WIND FIELDS
WILL BE INCREASING AS WELL WITH 500 MB WINDS INCREASING TO NEAR 40
KTS BY TUESDAY AFTERNOON. INCREASING LOW AND MID-LEVEL WINDS
PRODUCES 0-6KM VERTICAL SHEAR MAGNITUDES OF 35-40 KTS...SUPPORTIVE
OF SUSTAINING UPDRAFTS. THUS A RISK FOR STRONG TO SEVERE
THUNDERSTORMS WILL EXIST LATE IN THE DAY INTO THE MID-EVENING
HOURS WITH THE PRIMARY THREAT AREA BEING FROM THE NORTH CHAMPLAIN
VALLEY WESTWARD. CONVECTIVE MODE WOULD LIKELY TAKE THE FORM OF
LINE SEGMENTS...AN INDICATION OFFERED BY SOME OF THE HI- RES
CONVECTION-ALLOWING MODELS. THIS MATCHES UP WELL WITH SPC`S
AFTERNOON DAY 2 CONVECTIVE OUTLOOK. THERE`S SOME QUESTION HOW FAR
EAST THE STRONG TO SEVERE THUNDERSTORMS WILL MAKE IT AS
INSTABILITY WILL BE WANING. FOR NOW I HAVE ADDED ENHANCED WORDING
FOR GUSTY WINDS AND HEAVY RAINFALL FROM THE NORTHERN CHAMPLAIN
VALLEY TO THE SAINT LAWRENCE VALLEY.
FOR WEDNESDAY: COLD FRONT THAT WILL TRIGGER THE STORMS TUESDAY
IS EXPECTED TO SLOWLY DRIFT EASTWARD. IT`S DIFFICULT TO PINPOINT
EXACT FRONTAL POSITION AS THAT WILL BE AFFECTED TO SOME DEGREE BY
SHOWERS/STORMS TUESDAY EVENING. PLENTY OF CLOUDS WILL LIKELY BE IN
PLACE AHEAD OF THE FRONT...WHICH PLACES SOME QUESTION ON HOW MUCH
INSTABILITY CAN BE PRODUCED. HOWEVER...WIND FIELDS WEDNESDAY WILL
BE MORE THAN SUPPORTIVE OF ORGANIZED THUNDERSTORMS IF ANY CAN
DEVELOP. BASED ON PRESENT INDICATIONS FEEL THE PRIMARY AREA FOR ANY
STRONGER STORMS WOULD BE FROM THE CHAMPLAIN VALLEY
EASTWARD - BUT I WON`T INDICATE ENHANCED WORDING YET UNTIL THERE`S
MORE CLARITY ON THE DEGREE OF INSTABILITY. HAVE GONE WITH HIGH
CHANCE POPS FROM THE CHAMPLAIN VALLEY EAST TAPERING TO
CHANCE/SLIGHT CHANCE WITH WESTWARD EXTENT. STILL QUITE WARM AND
HUMID...BUT CLOUDS WILL KEEP TEMPERATURES DOWN SOMEWHAT. I`VE GONE
WITH HIGHS IN THE MID TO UPPER 80S WITH SLIGHTLY COOLER LOWS IN
THE LOW/MID 60S (A FEW UPPER 60S POSSIBLE CHAMPLAIN VALLEY AND
EAST VT).
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 300 AM EDT MONDAY...TRANSITIONAL PERIOD AS WE PROGRESS FROM
THE WEDNESDAY NIGHT/THURSDAY TIME FRAME INTO NEXT WEEKEND. THIS
MORNING`S GLOBAL SOLUTIONS MAINTAIN DECENT OVERALL CONSISTENCY IN
SHOWING FRONTAL BOUNDARY PROGRESSING SLOWLY SOUTH AND EAST
THROUGH THE AREA ON WED NT/THURSDAY WITH A CONTINUED CHANCE OF
SHOWERS/THUNDER. BEST THREAT OF THUNDER WILL GENERALLY OCCUR
ACROSS EASTERN AND SOUTHERN VT COUNTIES IN CLOSER PROXIMITY TO
DEPARTING BOUNDARY AND PBL INSTABILITY. COULD STILL SEE SOME
HEAVIER DOWNPOURS WITH ANY ACTIVITY GIVEN PWATS REMAIN HIGH
ACROSS THESE AREAS. FURTHER WEST TRENDING SLOWLY PCPN-FREE AS
POST- FRONTAL LOW LEVEL DRYING IS USHERED IN ON DEVELOPING
WEST/NORTHWESTERLY FLOW.
BY FRIDAY LARGE-SCALE DRYING CONTINUES WITH ANY LINGERING SHOWER
ACTIVITY ACROSS THE EAST DIMINISHING OVER TIME AS FRONTAL
BOUNDARY PULLS SLOWLY AWAY TO OUR EAST. THEREAFTER HIGH PRESSURE
BUILDS INTO THE REGION SETTING THE STAGE FOR ANOTHER NICE WEEKEND
WITH LOWER HUMIDITY VALUES. COULD SEE SOME LINGERING CLOUDS HERE
AND THERE WITH PARENT UPPER H5 TROUGH SWINGING THROUGH...BUT
GENERAL IDEA OF CLEAR TO PTLY CLOUDY SKIES APPEARS REASONABLE
ATTM. TEMPERATURES GENERALLY WITHIN A FEW DEGREES OF SEASONAL
EARLY SUMMER NORMS WITH HIGHS IN THE MID 70S TO LOWER 80S AND
OVERNIGHT LOWS IN THE 50S TO AROUND 60 (SLIGHTLY MILDER WED
NIGHT).
&&
.AVIATION /20Z MONDAY THROUGH SATURDAY/...
THROUGH 18Z TUESDAY...VFR CONDITIONS EXPECTED THROUGH THE PERIOD.
LATEST GUIDANCE SUGGESTING MID LEVEL CLOUDS THAT WERE OVER THE REGION
THIS MORNING AND EARLY THIS AFTERNOON...WITH JUST SOME CUMULUS
CLOUDS AND SOME HIGH THIN CIRRUS CLOUDS EXPECTED. THE CUMULUS
CLOUDS WILL DISSIPATE AROUND 00Z TUESDAY DUE TO THE LOSS OF
DAYTIME SURFACE HEATING. EXPECTING MAINLY CLEAR SKIES OR JUST SOME
HIGH THIN CIRRUS CLOUDS AT TIMES OVERNIGHT TONIGHT. GUIDANCE
HINTING AT SOME FOG LATE TONIGHT...BUT WINDS JUST ABOVE THE
SURFACE ARE FAIRLY STRONG...SO NOT EXPECTING ANY FOG TO DEVELOP
OVERNIGHT AT THIS TIME. SURFACE PRESSURE GRADIENT TO TIGHTEN ACROSS
THE REGION DURING THE DAY ON TUESDAY...SO SOME SOUTHERLY SURFACE
WIND GUSTS AROUND 20 KNOT ARE POSSIBLE FROM 13Z-18Z AND BEYOND ON
TUESDAY.
OUTLOOK 18Z TUESDAY THROUGH SATURDAY...
18Z TUESDAY ONWARD...MAINLY VFR THOUGH WITH A SLOWLY INCREASING
CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH THE PERIOD AS A WEAK
FRONTAL BOUNDARY MOVES INTO THE REGION. MVFR CIGS AND BRIEF IFR
VSBYS POSSIBLE WITH ANY SHOWERS OR THUNDERSTORMS. HIGHEST COVERAGE
DURING AFTERNOON/EARLY EVENING HOURS. RIDGE OF HIGH PRESSURE
BUILDS EAST FROM THE GREAT LAKES BY FRIDAY WITH SHOWER THREAT
DIMINISHING. EXPECTING VFR CONDITIONS UNDER SURFACE HIGH PRESSURE
AREA FRIDAY NIGHT AND SATURDAY.
&&
.EQUIPMENT...
AS OF 156 PM EDT MONDAY...THE AUTOMATED WEATHER OBSERVING SYSTEM
(AWOS) AT THE RUTLAND-SOUTHERN VERMONT REGIONAL AIRPORT (KRUT)
WILL BE OUT OF SERVICE ON TUESDAY, JULY 1, FROM 14Z-18Z (1000 AM
EDT-200 PM EDT) FOR MAINTENANCE.
THE TEMPERATURE/DEW POINT DATA SENSORS AT THE AUTOMATED WEATHER
OBSERVING SYSTEM (AWOS) AT THE NEWPORT STATE AIRPORT IN NEWPORT
VERMONT (KEFK) ARE OUT OF SERVICE AT THIS TIME. THE VERMONT
AGENCY OF TRANSPORTATION HAS INFORMED THE NATIONAL WEATHER SERVICE
IN BURLINGTON THAT PARTS ARE ON BACK ORDER TO FIX THIS, BUT THAT
TEMPERATURE/DEW POINT DATA AT THIS SITE MAY NOT BE RESTORED UNTIL
EARLY SEPTEMBER.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LOCONTO
NEAR TERM...LOCONTO
SHORT TERM...LOCONTO
LONG TERM...JMG
AVIATION...WGH
EQUIPMENT...WGH
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
351 PM EDT MON JUN 30 2014
.SYNOPSIS...
HIGH PRESSURE OFF THE EAST COAST WILL CONTINUE TO PUMP A SOUTHERLY
FLOW OF VERY WARM AND HUMID AIR FOR NEW YORK AND PENNSYLVANIA
THROUGH TUESDAY. WITH A WARM AND HUMID AIR MASS IN PLACE EXPECT
MORE SCATTERED SHOWERS AND THUNDERSTORMS THIS EVENING. A COLD
FRONT WILL BRING MORE WIDESPREAD SHOWERS AND THUNDERSTORMS
TUESDAY AFTERNOON AND NIGHT. SOME OF THIS STORMS MAY PRODUCE STRONG
WINDS AND VERY HEAVY RAIN LATER TUESDAY, ESPECIALLY OVER CENTRAL
NY. THIS FRONT WILL LINGER ACROSS THE REGION THROUGH WEDNESDAY
WITH MORE SHOWERS AND THUNDERSTORMS POSSIBLE. BY THURSDAY A WAVE
OF LOW PRESSURE IS EXPECTED TO FORM OVER SOUTHEAST PENNSYLVANIA
AND NEW JERSEY BRINGING MORE SCATTERED SHOWERS AND THUNDERSTORMS
TO THE REGION.
&&
.NEAR TERM /THROUGH TUESDAY/...
RADARS SHOWS ISLD SHRA POPPING UP ACROSS PARTS OF CENTRAL NY AND
NERN PA. SPC MESOANALYSIS SHOWS MIXED LAYER CAPES BETWEEN 1000 AND
1500 J/KG ACRS C NY AND NC PA. WITH CONTINUED INSOLATION I EXPECT
MIXED LAYER CAPES TO APPRCH 2000 J/KG BY LATE AFTERNOON WITH SFC
BASED CAPES OVER 2500 J/KG. THIS IS NOT FAR OFF FROM THE 12Z NAM
PROJECTIONS. THE 12Z GFS HAS A LITTLE LESS CAPE BUT IT IS IN THE
BALL PARK. THE LARGER SCALE FORCING WAS RATHER WEAK THIS AFTERNOON.
LATEST RAP SHOWS A WEAK UPPER LEVEL PV LOBE TRACK ACRS C NY AND NE
PA THIS AFTERNOON. THIS FEATURE PASSES E OF NY AND PA THIS EVENING IN
TANDEM WITH THE LOSS OF THE DAY/S HEATING. FOR POPS I RAMP UP TO
LOW CHC IN THE HILLS OF C NY BY ARND 21Z. I ANTICIPATE SOME MTN
VALLEY CIRCULATIONS AND OR UPSLOPE WILL AIDE IN DEVELOPMENT. BUT
BY AND LARGE...THE ACVTY WILL REMAIN ISLD FOR THE MOST PART. WITH
DECENT CAPE I WUD NOT SURPRISE THAT WE SEE A STRG STORM OR TWO.
ALL THE ACVTY WILL WANE AFTER SUNSET.
FOR TUESDAY...THERE ARE MULTIPLE HAZARDS TO CONSIDER. FIRST, ISSUED
A HEAT ADVY FOR OUR NRN COUNTIES ALONG THE FINGER LAKES DRAINAGE
AND LAKE ONTARIO PLAIN WHERE DEWPOINTS WILL POOL TO LOWER 70S AND
WITH SOME DOWNSLOPING ON SRLY WINDS AND THE GENERAL LOW ELEVATIONS
MAXES SHUD CLIMB ABV 90F. COMPUTED HEAT INDICES TUE AFTERNOON
RANGE FROM 97 TO 102F IN LARGE PARTS OF THESE AREAS.
NEXT IS THE POTENTIAL FOR STRG TO SVR THUNDERSTORMS WHICH REALLY
BEGINS LATE TUESDAY AFTERNOON AND LASTS INTO THE EVENING. WITH THE HEAT
AND HUMIDITY BUILDING DURG THE DAY AND INCREASING LOW-LEVEL SRLY
WINDS...MIXED LAYER CAPES LIKELY WILL EXCEED 2000 J/KG OVER MUCH
OF OUR FORECAST AREA. IN NE PA WHERE THE LL WINDS ARE LESS
STRONG...DEWPOINTS WILL BE A BIT LOWER. BUT STILL SEE CAPES ON THE
MODEL SOUNDINGS ARND 1500 J/KG. IN ADDTN...ALL LARGER SCALE
MODELS SHOW THAT A LOW-LEVEL WAVE WILL RIDE UP THE EASTERN SIDE
OF THE LARGE CYCLONE OVER THE NORTHERN PLAINS TO SC CANADA TUE.
THIS FEATURE WILL INCREASE THE LL WINDS AND AS A RESULT LL WIND
SHEAR WILL BE FAIRLY STRG. 0-1 KM BULK SHEAR IS PROJECTED TO BE 20
TO 25 KNOTS TUE AFTERNOON AND UP TO 30 KNOTS TUE EVE. THE 0-3 KM
BULK SHEAR IS SIMILAR TO THE 0-1 KM WITH THE 0-6 KM PROJECTED TO
BE ARND 30 TO 35 KNOTS. THE SHEAR WILL BE STRGR IN NC NY AND
WEAKER IN NE PA. HENCE SLGHT RISK AREA AS PER SPC DAY 2 OUTLOOK
LOOKS ON TRACK HAVING CNTRL NY AND NC PA IN THE SLGHT RISK AREA
TUE/TUE EVE. SINCE THE SHEAR IS STRG IN THE LL/S...ANY ORGANIZED
ACVTY LIKELY WILL BE LINEAR IN NATURE SO A FEW BROKEN LINES AND
EVEN A BOW ECHO IS POSSIBLE. IT DEPENDS ON HOW UNSTBL THE AMS
BECOMES AND IF THE LARGER SCALE FORCING WILL BE STRG ENUF TO FOCUS
THE CONVECTION.
NEXT THREAT WILL BE THE POTENTIAL FOR HEAVY RAIN AND LOCALIZED
FLASH FLOODING. PWATS APPRCH 2.0 INCHES AND THE LL FLOW IS STRG
ENUF TO BALANCE THE MEAN CLD LAYER WINDS. THUS IF THUNDERSTORMS
SHOW A TENDENCY TO BACK BUILD...INSTEAD OF BEING FORWARD
PROPAGATING...MESO BETA ELEMENT VECTORS ARE SMALL. I COULD SEE A
SCENARIO WHERE WE GET A LINE OR A FEW BROKEN LINES OF STRG TO SVR
STORMS LATE IN THE AFTERNOON/ERLY EVE THAT PROPAGATE FORWARD BUT
TREND TWD BACKWARD PROPAGATION LATER IN THE EVENING AS THE DAY/S
HEATING IS LOST AND STORMS WILL DERIVE INSTABILITY MORE FROM LL
ADVECTION. OUR LOCAL ANALOG SEVERE WEATHER CHECKLIST RETURNED THE
COLCHESTER FLASH FLOOD EVENT OF 2007 AND ALSO ANOTHER EVENT THAT
HAD A SMALLER FLASH FLOOD. BOTH OF THESE EVENTS WERE ASSOCIATED
WITH SOME SEVERE WIND GUSTS. FOR NOW HAVE HIGHLIGHTED THE WIND AND
HEAVY RAIN POTENTIAL IN HWO.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
TUESDAY NIGHT WILL SEE SHOWER AND THUNDERSTORM ACVTY CONTINUE
UNTIL AT LEAST LATE EVENING...BUT DEPENDING ON TIMING AND EXTENT
OF THE CONVECTION IT CUD LAST EVEN LONGER SO KEPT POPS GOING THRU
THE OVERNIGHT TO WED AM. THE FRONTAL BNDRY THAT PRESSES E TUESDAY
WILL REACH THE ERN LAKES BY WED AM.
THIS FRONT WILL PUSH EWRD ON WED AS ANOTHER UPPER LEVEL WAVE
MOVES E IN ASSCTN WITH THE WHOLE UPPER LEVEL TROUGH MOVG EWRD IN
SERN CANADA. THIS WILL LIKELY FIRE MORE SHRA AND TSRA FOR WED.
THE FRONT IS STILL PROJECTED TO BE LINGERING FROM SERN NY TO NE PA
IN THE BGM FORECAST AREA LATE WED NGT. THEN ON THURSDAY ANOTHER UPPER
LEVEL WAVE WILL PRESS THE FRONT WELL E OF THE REGION BUT ALL
SYNOPTIC MODELS INDICATE A SFC WAVE WILL FORM ON THIS BNDRY NEAR SERN
PA/NJ AND BRING MORE SHOWERS AND A FEW TSRA TO THE REGION FOR THU.
LATEST 12Z EURO SUGGESTS SOME TROPICAL MOISTURE CUD GET ENTRAINED
INTO THIS SURFACE WAVE AS AN UPPER LEVEL JET STREAK CIRCULATION
SETS UP TO OUR NORTHEAST. THIS HAS THE LOOK AND FEEL OF A
PREDECESSOR HEAVY TROPICAL RAIN EVENT. EURO QPF HAS A STRIPE OF
HEAVY RAIN ACRS NE PA TO ERN NY THU PM. SO KEPT POPS GOING INTO
THURSDAY. EVEN THOUGH IT DOESN/T LOOK LIKE THE TROPICAL SYSTEM
ITSELF WILL AFFECT THE REGION WE WILL HAVE TO WATCH THIS
POTENTIAL FOR ADDITIONAL HEAVY RAIN.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
345 PM EDT UPDATE...
FOLLOWED CLOSELY TO WPC GUIDANCE AND MADE MINOR ADJUSTMENTS TO THE
PREVIOUS FORECAST. THE UPPER LEVEL TROUGH THAT IS EXPECTED TO
PRODUCE SHOWERS AND THUNDERSTORMS THROUGH WEDNESDAY WILL BE
LOCATED OVER THE MID-WEST BY THURSDAY EVENING. THE TROUGH WILL
SLOWLY SHIFT EAST THROUGH SAT MORNING. THE EXPECTED COLD FRONT
WILL BE EAST OF THE CWA BY 00Z FRIDAY AND NW SFC IS EXPECTED TO
PREVAIL WITH COOLER AND DRIER AIR ALOFT. AS NW FLOW WILL PREVAIL
THROUGH FRIDAY AFTERNOON... UPSLOPE SHOWERS MAY DEVELOP DUE TO
LINGERING LOW LVL MOISTURE REMAINING OVER THE CWA.
FRIDAY NIGHT THE UPPR LVL TROUGH AXIS WILL SHIFT TO THE EAST OF
THE AREA AND SFC RIDGING WILL BUILD IN FROM THE WEST. THIS WILL
RESULT IN THE CHANCE FOR UPSLOPE SHOWERS DIMINISHING ACROSS THE
CWA. A SFC RIDGE IS EXPECTED TO REMAIN OVER THE CWA WITH QUIET
WEATHER THROUGH THE REMAINDER OF THE FORECAST PERIOD. TEMPERATURES
WILL BE ON THE WARMING TREND HEADING TOWARDS THE WEEKEND WITH
TEMPERATURES RISING INTO THE LOW TO MID 80S BY SUNDAY. LOW
TEMPERATURES ARE EXPECTED TO BE IN THE UPPR 40S TO MID 50S THROUGH
THE PERIOD.
&&
.AVIATION /20Z MONDAY THROUGH SATURDAY/...
ISOLATED PULSE SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS
AFTERNOON AS PLENTY OF LOW LVL MOISTURE IS PRESENT AND WEAK WAVES
ALOFT MOVE OVER THE REGION. THESE TYPE OF STORMS ARE EXPECTED TO
BE MOSTLY PULSE IN NATURE AND ARE EXPECTED TO BE BRIEF. DECIDED
NOT TO PLACE IN TAF DUE TO LOW CONFIDENCE IN TIMING AND PLACEMENT.
WILL KEEP A CLOSE EYE ON THE EVOLUTION OF THESE STORMS AND WILL
AMD IF NEEDED. THESE WILL BE DIURNALLY DRIVEN AND DISSIPATE BY
LATE EVENING. TONIGHT... EXPECT CLOUDS TO DIMINISH AND SKIES TO
BECOME HAZY. TOWARDS SUNRISE VISBYS MAY FALL TO AROUND 3SM BUT
EXPECT CONDITIONS TO IMPROVE SHORTLY AFTER SUNRISE AS WINDS ARE
EXPECTED TO INCREASE TO 12 KNOTS. A LOW END MVFR DECK MAY DEVELOP
IN THE EARLY MORNING HOURS BUT CONFIDENCE IS NOT HIGH ENOUGH TO
PLACE IN TAF ATTM. A VFR CU DECK WILL DEVELOP EARLY AFTERNOON
AGAIN DUE TO ALL THE LOW LVL MOISTURE PRESENT AHEAD OF THE NEXT
STORM SYSTEM.
OUTLOOK...
TUE AFTERNOON THROUGH TUE NGT...BRIEF RESTRICTIONS IN SCT
SHRA/TSRA...BEST POTENTIAL TUE LATE AFTN-EVE. POSSIBLE VALLEY FOG KELM
TUE NGT.
WED THROUGH THU...RESTRICTIONS FROM RA/TSRA AS MOIST COLD FRONT
MOVES THROUGH THE REGION...ESPECIALLY LATE WED TO EARLY THU.
THU NGT THROUGH FRI...VFR EXCEPT POSSIBLE VALLEY FOG KELM.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...HEAT ADVISORY FROM 1 PM TO 9 PM EDT TUESDAY FOR NYZ015>018.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DJN
LONG TERM...KAH
AVIATION...KAH
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
304 PM EDT MON JUN 30 2014
.SYNOPSIS...
HIGH PRESSURE OFF THE EAST COAST WILL CONTINUE TO PUMP A SOUTHERLY
FLOW OF VERY WARM AND HUMID AIR FOR NEW YORK AND PENNSYLVANIA
THROUGH TUESDAY. WITH A WARM AND HUMID AIR MASS IN PLACE EXPECT
MORE SCATTERED SHOWERS AND THUNDERSTORMS THIS EVENING. A COLD
FRONT WILL BRING MORE WIDESPREAD SHOWERS AND THUNDERSTORMS
TUESDAY AFTERNOON AND NIGHT. SOME OF THIS STORMS MAY PRODUCE STRONG
WINDS AND VERY HEAVY RAIN LATER TUESDAY, ESPECIALLY OVER CENTRAL
NY. THIS FRONT WILL LINGER ACROSS THE REGION THROUGH WEDNESDAY
WITH MORE SHOWERS AND THUNDERSTORMS POSSIBLE. BY THURSDAY A WAVE
OF LOW PRESSURE IS EXPECTED TO FORM OVER SOUTHEAST PENNSYLVANIA
AND NEW JERSEY BRINGING MORE SCATTERED SHOWERS AND THUNDERSTORMS
TO THE REGION.
&&
.NEAR TERM /THROUGH TUESDAY/...
RADARS SHOWS ISLD SHRA POPPING UP ACROSS PARTS OF CENTRAL NY AND
NERN PA. SPC MESOANALYSIS SHOWS MIXED LAYER CAPES BETWEEN 1000 AND
1500 J/KG ACRS C NY AND NC PA. WITH CONTINUED INSOLATION I EXPECT
MIXED LAYER CAPES TO APPRCH 2000 J/KG BY LATE AFTERNOON WITH SFC
BASED CAPES OVER 2500 J/KG. THIS IS NOT FAR OFF FROM THE 12Z NAM
PROJECTIONS. THE 12Z GFS HAS A LITTLE LESS CAPE BUT IT IS IN THE
BALL PARK. THE LARGER SCALE FORCING WAS RATHER WEAK THIS AFTERNOON.
LATEST RAP SHOWS A WEAK UPPER LEVEL PV LOBE TRACK ACRS C NY AND NE
PA THIS AFTERNOON. THIS FEATURE PASSES E OF NY AND PA THIS EVENING IN
TANDEM WITH THE LOSS OF THE DAY/S HEATING. FOR POPS I RAMP UP TO
LOW CHC IN THE HILLS OF C NY BY ARND 21Z. I ANTICIPATE SOME MTN
VALLEY CIRCULATIONS AND OR UPSLOPE WILL AIDE IN DEVELOPMENT. BUT
BY AND LARGE...THE ACVTY WILL REMAIN ISLD FOR THE MOST PART. WITH
DECENT CAPE I WUD NOT SURPRISE THAT WE SEE A STRG STORM OR TWO.
ALL THE ACVTY WILL WANE AFTER SUNSET.
FOR TUESDAY...THERE ARE MULTIPLE HAZARDS TO CONSIDER. FIRST, ISSUED
A HEAT ADVY FOR OUR NRN COUNTIES ALONG THE FINGER LAKES DRAINAGE
AND LAKE ONTARIO PLAIN WHERE DEWPOINTS WILL POOL TO LOWER 70S AND
WITH SOME DOWNSLOPING ON SRLY WINDS AND THE GENERAL LOW ELEVATIONS
MAXES SHUD CLIMB ABV 90F. COMPUTED HEAT INDICES TUE AFTERNOON
RANGE FROM 97 TO 102F IN LARGE PARTS OF THESE AREAS.
NEXT IS THE POTENTIAL FOR STRG TO SVR THUNDERSTORMS WHICH REALLY
BEGINS LATE TUESDAY AFTERNOON AND LASTS INTO THE EVENING. WITH THE HEAT
AND HUMIDITY BUILDING DURG THE DAY AND INCREASING LOW-LEVEL SRLY
WINDS...MIXED LAYER CAPES LIKELY WILL EXCEED 2000 J/KG OVER MUCH
OF OUR FORECAST AREA. IN NE PA WHERE THE LL WINDS ARE LESS
STRONG...DEWPOINTS WILL BE A BIT LOWER. BUT STILL SEE CAPES ON THE
MODEL SOUNDINGS ARND 1500 J/KG. IN ADDTN...ALL LARGER SCALE
MODELS SHOW THAT A LOW-LEVEL WAVE WILL RIDE UP THE EASTERN SIDE
OF THE LARGE CYCLONE OVER THE NORTHERN PLAINS TO SC CANADA TUE.
THIS FEATURE WILL INCREASE THE LL WINDS AND AS A RESULT LL WIND
SHEAR WILL BE FAIRLY STRG. 0-1 KM BULK SHEAR IS PROJECTED TO BE 20
TO 25 KNOTS TUE AFTERNOON AND UP TO 30 KNOTS TUE EVE. THE 0-3 KM
BULK SHEAR IS SIMILAR TO THE 0-1 KM WITH THE 0-6 KM PROJECTED TO
BE ARND 30 TO 35 KNOTS. THE SHEAR WILL BE STRGR IN NC NY AND
WEAKER IN NE PA. HENCE SLGHT RISK AREA AS PER SPC DAY 2 OUTLOOK
LOOKS ON TRACK HAVING CNTRL NY AND NC PA IN THE SLGHT RISK AREA
TUE/TUE EVE. SINCE THE SHEAR IS STRG IN THE LL/S...ANY ORGANIZED
ACVTY LIKELY WILL BE LINEAR IN NATURE SO A FEW BROKEN LINES AND
EVEN A BOW ECHO IS POSSIBLE. IT DEPENDS ON HOW UNSTBL THE AMS
BECOMES AND IF THE LARGER SCALE FORCING WILL BE STRG ENUF TO FOCUS
THE CONVECTION.
NEXT THREAT WILL BE THE POTENTIAL FOR HEAVY RAIN AND LOCALIZED
FLASH FLOODING. PWATS APPRCH 2.0 INCHES AND THE LL FLOW IS STRG
ENUF TO BALANCE THE MEAN CLD LAYER WINDS. THUS IF THUNDERSTORMS
SHOW A TENDENCY TO BACK BUILD...INSTEAD OF BEING FORWARD
PROPAGATING...MESO BETA ELEMENT VECTORS ARE SMALL. I COULD SEE A
SCENARIO WHERE WE GET A LINE OR A FEW BROKEN LINES OF STRG TO SVR
STORMS LATE IN THE AFTERNOON/ERLY EVE THAT PROPAGATE FORWARD BUT
TREND TWD BACKWARD PROPAGATION LATER IN THE EVENING AS THE DAY/S
HEATING IS LOST AND STORMS WILL DERIVE INSTABILITY MORE FROM LL
ADVECTION. OUR LOCAL ANALOG SEVERE WEATHER CHECKLIST RETURNED THE
COLCHESTER FLASH FLOOD EVENT OF 2007 AND ALSO ANOTHER EVENT THAT
HAD A SMALLER FLASH FLOOD. BOTH OF THESE EVENTS WERE ASSOCIATED
WITH SOME SEVERE WIND GUSTS. FOR NOW HAVE HIGHLIGHTED THE WIND AND
HEAVY RAIN POTENTIAL IN HWO.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
TUESDAY NIGHT WILL SEE SHOWER AND THUNDERSTORM ACVTY CONTINUE
UNTIL AT LEAST LATE EVENING...BUT DEPENDING ON TIMING AND EXTENT
OF THE CONVECTION IT CUD LAST EVEN LONGER SO KEPT POPS GOING THRU
THE OVERNIGHT TO WED AM. THE FRONTAL BNDRY THAT PRESSES E TUESDAY
WILL REACH THE ERN LAKES BY WED AM.
THIS FRONT WILL PUSH EWRD ON WED AS ANOTHER UPPER LEVEL WAVE
MOVES E IN ASSCTN WITH THE WHOLE UPPER LEVEL TROUGH MOVG EWRD IN
SERN CANADA. THIS WILL LIKELY FIRE MORE SHRA AND TSRA FOR WED.
THE FRONT IS STILL PROJECTED TO BE LINGERING FROM SERN NY TO NE PA
IN THE BGM FORECAST AREA LATE WED NGT. THEN ON THURSDAY ANOTHER UPPER
LEVEL WAVE WILL PRESS THE FRONT WELL E OF THE REGION BUT ALL
SYNOPTIC MODELS INDICATE A SFC WAVE WILL FORM ON THIS BNDRY NEAR SERN
PA/NJ AND BRING MORE SHOWERS AND A FEW TSRA TO THE REGION FOR THU.
LATEST 12Z EURO SUGGESTS SOME TROPICAL MOISTURE CUD GET ENTRAINED
INTO THIS SURFACE WAVE AS AN UPPER LEVEL JET STREAK CIRCULATION
SETS UP TO OUR NORTHEAST. THIS HAS THE LOOK AND FEEL OF A
PREDECESSOR HEAVY TROPICAL RAIN EVENT. EURO QPF HAS A STRIPE OF
HEAVY RAIN ACRS NE PA TO ERN NY THU PM. SO KEPT POPS GOING INTO
THURSDAY. EVEN THOUGH IT DOESN/T LOOK LIKE THE TROPICAL SYSTEM
ITSELF WILL AFFECT THE REGION WE WILL HAVE TO WATCH THIS
POTENTIAL FOR ADDITIONAL HEAVY RAIN.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
320 AM UPDATE...
MINOR FORECAST ADJUSTMENTS WERE MADE ACCOUNTING FOR LATEST WPC
GUIDANCE AND MODEL RUNS. MODELS STILL SHOW INCOMING SURFACE COLD
FRONT BECOMING NEARLY FLOW PARALLEL WITH TIME...SO THE FRONT
STRUGGLES TO PRESS THROUGH THE REGION BEFORE APPROACHING LONGWAVE
TROUGH FINALLY KICKS IT THROUGH. CONCERNS REMAIN FOR LOCALIZED
HEAVY RAINFALL AND POTENTIAL FOR STRONG THUNDERSTORMS...AS
DISCUSSED BELOW.
PREVIOUS DISCUSSION...
GLOBAL MODELS AND ENSEMBLES REMAIN CONSISTENT IN SUGGESTING AN
AMPLIFYING LONGWAVE TROF PATTERN ACROSS THE GREAT LAKES AND UPPER
MIDWEST THIS WEEK WHICH IS EXPECTED TO TRANSPORT DEEPER MOISTURE
FROM THE GULF STATES INTO THE NORTHEAST THROUGH THURSDAY. A COLD
FRONTAL PASSAGE IS STILL EXPECTED DURING THE THURSDAY-THURSDAY
NIGHT TIME FRAME OFFERING UP THE FINAL ROUNDS OF SHOWER AND
THUNDERSTORM ACTIVITY FOR THE REGION. ANY CONVECTIVE ACTIVITY IN
THIS AIRMASS WOULD BE CONDUCIVE TO LOCALLY HEAVY RAINFALL. DEEP
BULK SHEAR MAY ALSO BECOME FAVORABLE FOR STRONG THUNDERSTORMS...
BUT AT THIS POINT IN TIME...THIS IS LOW CONFIDENCE. THEN...A BROAD
AND UNSEASONABLY FRESH AREA OF CANADIAN HIGH PRESSURE IS FORECAST
TO BUILD IN FROM FRIDAY THROUGH THE HOLIDAY WEEKEND...WITH FAIR
SKIES AND HIGH TEMPERATURES IN THE 70S AND LOWS IN THE 50S.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
ISOLATED PULSE SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS
AFTERNOON AS PLENTY OF LOW LVL MOISTURE IS PRESENT AND WEAK WAVES
ALOFT MOVE OVER THE REGION. THESE TYPE OF STORMS ARE EXPECTED TO
BE MOSTLY PULSE IN NATURE AND ARE EXPECTED TO BE BRIEF. DECIDED
NOT TO PLACE IN TAF DUE TO LOW CONFIDENCE IN TIMING AND PLACEMENT.
WILL KEEP A CLOSE EYE ON THE EVOLUTION OF THESE STORMS AND WILL
AMD IF NEEDED. THESE WILL BE DIURNALLY DRIVEN AND DISSIPATE BY
LATE EVENING. TONIGHT... EXPECT CLOUDS TO DIMINISH AND SKIES TO
BECOME HAZY. TOWARDS SUNRISE VISBYS MAY FALL TO AROUND 3SM BUT
EXPECT CONDITIONS TO IMPROVE SHORTLY AFTER SUNRISE AS WINDS ARE
EXPECTED TO INCREASE TO 12 KNOTS. A LOW END MVFR DECK MAY DEVELOP
IN THE EARLY MORNING HOURS BUT CONFIDENCE IS NOT HIGH ENOUGH TO
PLACE IN TAF ATTM. A VFR CU DECK WILL DEVELOP EARLY AFTERNOON
AGAIN DUE TO ALL THE LOW LVL MOISTURE PRESENT AHEAD OF THE NEXT
STORM SYSTEM.
OUTLOOK...
TUE AFTERNOON THROUGH TUE NGT...BRIEF RESTRICTIONS IN SCT
SHRA/TSRA...BEST POTENTIAL TUE LATE AFTN-EVE. POSSIBLE VALLEY FOG KELM
TUE NGT.
WED THROUGH THU...RESTRICTIONS FROM RA/TSRA AS MOIST COLD FRONT
MOVES THROUGH THE REGION...ESPECIALLY LATE WED TO EARLY THU.
THU NGT THROUGH FRI...VFR EXCEPT POSSIBLE VALLEY FOG KELM.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...HEAT ADVISORY FROM 1 PM TO 9 PM EDT TUESDAY FOR NYZ015>018.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DJN
LONG TERM...JAB/MDP
AVIATION...KAH
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
149 PM EDT MON JUN 30 2014
.SYNOPSIS...
HIGH PRESSURE OFF THE EAST COAST WILL CONTINUE TO PUMP A SOUTHERLY
FLOW OF VERY WARM AND HUMID AIR FOR NEW YORK AND PENNSYLVANIA
THROUGH TUESDAY. WITH THE WARM AND HUMID AIR MASS IN PLACE
EXPECT MORE SCATTERED SHOWERS AND THUNDERSTORMS THIS AFTERNOON
AND EVENING. A COLD FRONT WILL BRING MORE WIDESPREAD SHOWERS AND
THUNDERSTORMS TUESDAY. SOME OF THIS STORMS MAY PRODUCE STRONG
WINDS AND VERY HEAVY RAIN LATER TUESDAY, ESPECIALLY OVER CENTRAL
NY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
RADAR SHOWS SHRA AND ISLD TSRA PERSISTING IN THE SRN CATSKILLS AT
THIS TIME IN ASSCTN WITH A WEAKENING SHRT WAVE THAT HAS TRACKED E
OVERNIGHT AND WAS NOW ALMOST UNDER THE UPPER LEVEL RDG AXIS. THIS
FEATURE WILL CONT E AND ALL PRECIP SHUD EXIT THE SRN CATSKILLS BY
AFTERNOON. HAVE LIKELY POPS FOR THE NEXT HOUR OR SO TO COVER DOWN
THERE. REST OF CENTRAL NY/NE PA WAS DRY AT THIS TIME.
MAIN QUESTION IS WHERE AND HOW MUCH CONVECTION DEVELOPS AGAIN THIS
AFTERNOON AND INTO THE EVENING ASSCTD WITH STRG LATE JUNE
INSOLATION. MODELS BUILD UP CAPES BETWEEN 1000 AND 2000 J/KG OR
EVEN MORE ESPECIALLY ACROSS NC NY TO WRN NY WITH MUCH LESSER CAPE
VALUES FARTHER SOUTH TWD NE PA AND THE CATSKILLS. THIS IS ASSCTD
WITH STRGER SWRLY LOW-LEVEL FLOW THAT CONTINUES TO PREFERENTIAL
ADVECT HIGHER BNDRY LAYER DEWPOINTS UP THRU WRN NY WITH HIGHER
MEAN BL DEWPOINTS THAN FARTHER SOUTHEAST INTO NE PA AND THE
CATSKILLS. CAPES THIS AFTERNOON CONSISTENTLY ARE HIGHER IN OUR NW
COUNTIES...FINGER LAKES TO SYR AREA ON ALL MODELS. THE LATEST NAM
HAS CAPES APPROACHING 3000 J/KG AND IN MANY OF THESE AREAS WELL
VER 2000 J/KG!! THE GFS AND EURO ARE TAMER WITH 1000 TO 2000 J/KG
WHICH STILL IS HEALTHY. THE NAM HAS SFC DWPTS ARND 71-72F IN NC NY WHICH
IS NOT OUT OF THE QUESTION.
SO WE KNOW WE ARE GOING TO HAVE MORE THAN SUFFICIENT CAPE IN
CENTRAL NY FOR TSRA. MAIN QUESTION IS WHERE IS THE FORCING GOING
TO COME FROM? THE WIND SHEAR IS ALSO FAIRLY WEAK AS WELL SO ANY
STORMS THAT FORM WON`T BE TOO ORGANIZED. WATER VAPOR IMAGERY
CONTINUES TO SHOW A BARRAGE OF SMALLER SHORT WAVES OR MORE LIKELY
CONVECTIVELY INDUCED WAVES FROM UPSTREAM CONVECTION HEADING E-NE
TWD NY AND PA THRU TUESDAY AM. THE NEXT WAVE THAT WAS APPROACHING
OUR AREA WAS OVER THE ERN LAKES ASSCTD WITH DARKENING ON THE WATER
VAPOR IMAGERY. LATEST RAP ALSO SHOWS THIS WAVE ACVTY AS TROP
PRESSURES ARE A LOCAL MAXIMUM IN PRESSURE BASED ON THE 1.5 PVU
UNIT SFC. MODEL SOUNDINGS SHOW SOME OMEGA THIS AFTERNOON AS WELL
BEFORE THE MODELS CONVECT OUT SUGGESTING SOME SORT OF LARGER SCALE
ASCENT. SO I EXPECT SOME CONVECTION TO FIRE IN C NY AND TO A
LESSER EXTENT NE PA THIS AFTERNOON INTO THE EVENING.
NEXT QUESTION IS HOW WIDESPREAD? THE LATEST MESOSCALE CONVECTIVE
ALLOWING MODELS DO SHOW SCT ACVTY THIS AFTERNOON MAINLY IN CNTRL
AND WRN NY BUT VARY IN HOW WIDESPREAD THE ACVTY IS. LOOKING AT
VSBL SATELLITE IMAGERY YOU CAN SEE A CUMULUS FIELD EVOLVING ACRS C
AND WRN NY WITH SOME CLUMPING APPARENT IN A FEW SPOTS. GIVEN THAT
THE UPPER LEVEL WAVE IS RATHER WEAK AND THERE IS NO WELL DEFINED
BOUNDARIES I WILL LIMIT POPS FROM SLGHT CHC FOR TSRA THIS
AFTERNOON FOR C AND NC NY. I WILL PEAK THE POPS AT CHC IN OUR
HIGHER TERRAIN OF CNTRL NY WHERE MTNS ADD TO THE UPDRAFTS. GIVEN
THE POTENTIAL HIGH CAPES AND DRY AIR AT MID-LEVELS...THERE CUD BE
A STRONG STORM OR TWO. LOCAL CHECKLIST RETURNS MAINLY ISOLATED PULSE SEVERE
STORMS USING SYR NAM SOUNDING. SO I WILL MENTION CHC FOR STRONG TO
ISOLATED SEVERE STORM IN HWO FOR AFTERNOON.
AFTER SUNSET...ACVTY SHUD WIND DOWN WITH LOSS OF DAY/S HEATING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
500 AM UPDATE...
A COLD FRONT NOW OVER THE UPPER MIDWEST WILL MOVE INTO WESTERN NY
BY 0Z WEDNESDAY. AHEAD OF THIS TRIGGER WILL BE A RIPE ATMOSPHERE
WITH DAYTIME HIGHS IN THE UPPER 80S TO LOWER 90S AND DEWPOINTS
NEAR 70. THIS WILL TRANSLATE TO PLENTY OF INSTABILITY AND
POTENTIAL JUICE FOR STORMS WITH CAPES AROUND 2000 J/KG. WITH 0-6
KM SHEAR LACKING A BIT (25 KTS) AND A WARM/HUMID ATMOSPHERE, LARGE
HAIL DOES NOT APPEAR TO BE A PRIMARY RISK. DAMAGING WINDS WILL BE
A MUCH GREATER THREAT WITH VERY DRY AIR BETWEEN 700 AND 500 MB AND
STRONG LOW TO MID LEVEL SHEAR, SUPPORTING THE POSSIBILITY OF BOW ECHOES.
IN ADDITION TO THE WIND THREAT, VERY HEAVY RAIN WILL BE LIKELY
WITH FLASH FLOODING A CONCERN WITH PWATS (A MEASURE OF MOISTURE IN
THE ATMOSPHERE) OVER 2 INCHES, OR OVER 200% OF NORMAL! OUR SEVERE
WEATHER CHECKLIST HAS MANY PAST ANALOGS OF A BROKEN LINE OF
THUNDERSTORMS AS THE MAIN STORM MODE, WITH A FEW PULSE STORMS
POSSIBLE OUT AHEAD OF THE LINE. CONFIDENCE IN A BROKEN LINE OF
STORMS AS THE STORM MODE IS HIGHER THAN AVERAGE GIVEN THE AMOUNT
OF MATCHES IN THE DATABASE. BASED ON TIMING THIS SHOULD MOVE INTO
THE CWA BETWEEN 20Z AND 24Z. WILL CONTINUE TO HIGHLIGHT THE
DAMAGING WIND AND HEAVY RAIN THREAT IN THE HWO. WILL ALSO ADD
MENTION OF GUSTY WINDS AND HEAVY RAIN TO THE FORECAST LATE TUESDAY
(MAINLY NY STATE) AS SPC HAS MOST OF THE AREA IN A SLIGHT RISK.
THE COLD FRONT MENTIONED ABOVE MOVES THROUGH PART OF THE AREA
WEDNESDAY, BUT MAY HANG UP OVER NEPA. THIS WILL KEEP
SHOWERS/STORMS AROUND BOTH WEDNESDAY AND WEDNESDAY NIGHT.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
320 AM UPDATE...
MINOR FORECAST ADJUSTMENTS WERE MADE ACCOUNTING FOR LATEST WPC
GUIDANCE AND MODEL RUNS. MODELS STILL SHOW INCOMING SURFACE COLD
FRONT BECOMING NEARLY FLOW PARALLEL WITH TIME...SO THE FRONT
STRUGGLES TO PRESS THROUGH THE REGION BEFORE APPROACHING LONGWAVE
TROUGH FINALLY KICKS IT THROUGH. CONCERNS REMAIN FOR LOCALIZED
HEAVY RAINFALL AND POTENTIAL FOR STRONG THUNDERSTORMS...AS
DISCUSSED BELOW.
PREVIOUS DISCUSSION...
GLOBAL MODELS AND ENSEMBLES REMAIN CONSISTENT IN SUGGESTING AN
AMPLIFYING LONGWAVE TROF PATTERN ACROSS THE GREAT LAKES AND UPPER
MIDWEST THIS WEEK WHICH IS EXPECTED TO TRANSPORT DEEPER MOISTURE
FROM THE GULF STATES INTO THE NORTHEAST THROUGH THURSDAY. A COLD
FRONTAL PASSAGE IS STILL EXPECTED DURING THE THURSDAY-THURSDAY
NIGHT TIME FRAME OFFERING UP THE FINAL ROUNDS OF SHOWER AND
THUNDERSTORM ACTIVITY FOR THE REGION. ANY CONVECTIVE ACTIVITY IN
THIS AIRMASS WOULD BE CONDUCIVE TO LOCALLY HEAVY RAINFALL. DEEP
BULK SHEAR MAY ALSO BECOME FAVORABLE FOR STRONG THUNDERSTORMS...
BUT AT THIS POINT IN TIME...THIS IS LOW CONFIDENCE. THEN...A BROAD
AND UNSEASONABLY FRESH AREA OF CANADIAN HIGH PRESSURE IS FORECAST
TO BUILD IN FROM FRIDAY THROUGH THE HOLIDAY WEEKEND...WITH FAIR
SKIES AND HIGH TEMPERATURES IN THE 70S AND LOWS IN THE 50S.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
ISOLATED PULSE SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS
AFTERNOON AS PLENTY OF LOW LVL MOISTURE IS PRESENT AND WEAK WAVES
ALOFT MOVE OVER THE REGION. THESE TYPE OF STORMS ARE EXPECTED TO
BE MOSTLY PULSE IN NATURE AND ARE EXPECTED TO BE BRIEF. DECIDED
NOT TO PLACE IN TAF DUE TO LOW CONFIDENCE IN TIMING AND PLACEMENT.
WILL KEEP A CLOSE EYE ON THE EVOLUTION OF THESE STORMS AND WILL
AMD IF NEEDED. THESE WILL BE DIURNALLY DRIVEN AND DISSIPATE BY
LATE EVENING. TONIGHT... EXPECT CLOUDS TO DIMINISH AND SKIES TO
BECOME HAZY. TOWARDS SUNRISE VISBYS MAY FALL TO AROUND 3SM BUT
EXPECT CONDITIONS TO IMPROVE SHORTLY AFTER SUNRISE AS WINDS ARE
EXPECTED TO INCREASE TO 12 KNOTS. A LOW END MVFR DECK MAY DEVELOP
IN THE EARLY MORNING HOURS BUT CONFIDENCE IS NOT HIGH ENOUGH TO
PLACE IN TAF ATTM. A VFR CU DECK WILL DEVELOP EARLY AFTERNOON
AGAIN DUE TO ALL THE LOW LVL MOISTURE PRESENT AHEAD OF THE NEXT
STORM SYSTEM.
OUTLOOK...
TUE AFTERNOON THROUGH TUE NGT...BRIEF RESTRICTIONS IN SCT
SHRA/TSRA...BEST POTENTIAL TUE LATE AFTN-EVE. POSSIBLE VALLEY FOG KELM
TUE NGT.
WED THROUGH THU...RESTRICTIONS FROM RA/TSRA AS MOIST COLD FRONT
MOVES THROUGH THE REGION...ESPECIALLY LATE WED TO EARLY THU.
THU NGT THROUGH FRI...VFR EXCEPT POSSIBLE VALLEY FOG KELM.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...HEAT ADVISORY FROM 1 PM TO 9 PM EDT TUESDAY FOR NYZ015>018.
&&
$$
SYNOPSIS...DJN/HEDEN
NEAR TERM...DJN
SHORT TERM...HEDEN
LONG TERM...JAB/MDP
AVIATION...KAH
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
657 PM EDT MON JUN 30 2014
.SYNOPSIS...
HIGH PRESSURE ALONG THE EAST COAST WILL MOVE OFFSHORE TONIGHT. A COLD
FRONT WILL MOVE ACROSS THE AREA ON TUESDAY. A SECONDARY COLD FRONT
WILL FOLLOW WEDNESDAY EVENING. DRY AND COOLER WEATHER WILL MOVE
IN BY FRIDAY AS A LARGE AREA OF CANADIAN HIGH PRESSURE BUILDS
ACROSS THE GREAT LAKES.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
REDUCE THE AMOUNT OF CLOUDS FOR THE NEXT FEW HOURS OTHERWISE NO
CHANGES. CONVECTION OVER THE WESTERN LAKES WILL NEED TO BE WATCHED
BUT EXPECT A LOT OF WEAKENING BEFORE IT APPROACHES. SMALL POPS
FINE FOR NOW.
PREVIOUS...MAIN QUESTION OVERNIGHT IS WHETHER CONVECTION DEVELOPING OVER
ILLINOIS WILL SPREAD EAST AND AFFECT NORTH OHIO AFTER MIDNIGHT.
THE SSEO AND MORE RECENT RUNS OF THE HRRR INDICATE THAT THE
CONVECTION WILL MOVE TOWARD THE REGION BUT WILL WEAKEN RAPIDLY
AFTER MIDNIGHT AS IT APPROACHES NW OHIO. DIURNAL TIMING DOES NOT
FAVOR THE PERSISTENCE OF THE CONVECTION BUT WE WILL CONTINUE THE
CHANCE OF STORMS IN THE THE NORTHWEST PORTION OF THE FORECAST AREA
ESPECIALLY NEAR TOL. ELSEWHERE A TRIGGER FOR CONVECTION IS
DIFFICULT TO DETERMINE AND POPS HAVE BEEN SET TO NEAR 15 PERCENT.
RATHER HIGH DEWPOINTS ALONG WITH WARM BOUNDARY LAYER TEMPERATURES
WILL HELP KEEP TEMPERATURES UP TONIGHT SO HAVE CONTINUED THE
FORECAST PREDICTION OF A LOW FROM 70 TO 75.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/...
VERY WARM AND HUMID CONDITIONS WILL BE REPLACED WITH MORE SEASONAL
WEATHER BY THE END OF THIS PERIOD. THE APPROACH AND PASSAGE OF A
COLD FRONT TUESDAY AFTERNOON WILL BE A TRIGGER FOR WIDESPREAD
CONVECTIVE DEVELOPMENT. MLCAPE WILL BE RATHER ELEVATED AND WIND
SHEAR WILL BE SUFFICIENT FOR ORGANIZED CONVECTIVE DEVELOPMENT
ESPECIALLY NEAR LAKE ERIE WHERE LAKE BREEZE BOUNDARIES AND ENHANCED
LOW LEVEL SHEAR WILL AID IN PRODUCING ROTATING STORMS.
VERY WARM 850 MB TEMPERATURES FROM 18-20C WOULD SUGGEST SURFACE
TEMPERATURES RISING TO NEAR 90 BUT CONVECTIVE DEVELOPMENT MAY
PREVENT MAX HEATING SO WILL CONTINUE THE FORECAST WITH THE
TEMPERATURES IN THE MID TO UPPER 80S.
LINGERING CONVECTION WILL MOVE OUT OF THE EASTERN COUNTIES TUESDAY EVENING.
THE MAIN TROUGH AXIS AND ITS ATTENDANT COLD FRONT WILL SHIFT EAST
AND CROSS THE REGION WEDNESDAY AND WEDNESDAY EVENING. SCATTERED
SHOWERS WITH A LITTLE THUNDER CAN BE EXPECTED BUT TIMING THE SMALL
SCALE FEATURES ARE DIFFICULT.
COOLER AND LESS HUMID CONDITIONS WILL PREVAIL ESPECIALLY BY THURSDAY.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
MODELS REMAIN IN GOOD AGREEMENT ON THE EXTENDED. MODELS CONTINUE
TO FORECAST LARGE AREA OF HIGH PRESSURE TO MOVE EAST ACROSS THE
LOWER GREAT LAKES OVER THE WEEKEND. THE ENTIRE WEEKEND SHOULD BE
DRY WITH TEMPERATURES STARTING OUT A LITTLE BELOW NORMAL...AND
GRADUALLY WARMING TO NEAR NORMAL BY SUNDAY. MODELS DIVERGE ON
MONDAY AS ECMWF MOVES THE RIDGE EAST AND ANOTHER FRONT SWEEPS ACROSS
THE GREAT LAKES. THE GFS ON THE OTHER HAND MAINTAINS THE RIDGE
THROUGH MONDAY. FOR NOW WILL SPIT THE DIFFERENCE AND LEAN TOWARD
CONTINUITY AND GO SLIGHT CHANCE POPS.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
SCT TO BKN CU FIELD AT 2500-3500 FT OR HIGHER WILL GRADUALLY
DIMINISH AFTER SUNSET. HOWEVER...CLOUDS WILL GRADUALLY THICKEN AND
LOWER FROM THE WEST OVERNIGHT. EXPECT WIDESPREAD MARGINAL
CONDITIONS BY DAYBREAK TUESDAY.
THERE IS ONLY A MINIMAL CHANCE FOR TSRA THIS AFTERNOON AND
EVENING SO WILL KEEP OUT OF THE TAFS. A NEW BAND OF CONVECTION
WITH MAY BE MOVING NEAR TOL BY 12Z TUE. BETTER CHANCE OF
CONVECTION EAST HALF TOMORROW AFTERNOON.
OUTLOOK...NON VFR IN SHOWERS AND THUNDERSTORMS LATE TUESDAY THROUGH
THURSDAY.
&&
.MARINE...
SOUTH TO SSW WINDS SHOULD GENERALLY CONTINUE...THEN TURN TO THE WEST
TUESDAY AS THE FIRST OF A SERIES OF FRONTS MOVES ACROSS LAKE ERIE.
CONDITIONS WILL BECOME CHOPPY ON THE LAKE TUESDAY EVENING...BUT
SHOULD REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA. THE SECOND COLD
FRONT WILL MOVE SE ACROSS THE LAKE WED TURNING THE WINDS NW BUT WIND
SPEEDS WILL ALSO BE GRADUALLY DECREASING TO 5 TO 15 KNOTS AS THE
WEATHER SYSTEMS WEAKEN. HIGH PRESSURE MOVES OVER THE LAKE FRI TO
CALM THE WINDS FOR FRI NIGHT.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LAPLANTE
NEAR TERM...KUBINA/LAPLANTE
SHORT TERM...LAPLANTE
LONG TERM...DJB
AVIATION...DJB
MARINE...DJB
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
433 PM EDT MON JUN 30 2014
.SYNOPSIS...
A WARM AND HUMID AIR MASS WILL CONTINUE TO ALLOW A THREAT FOR
SHOWERS AND THUNDERSTORMS THROUGH THE FIRST HALF OF THE WEEK. AS A
COLD FRONT MOVES THROUGH ON WEDNESDAY...DRIER AND COOLER
CONDITIONS ARE EXPECTED FOR THE END OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
ALL THAT REMAINS OF THE DECAYING MCS THAT TRAVELED SOUTHEAST
THROUGH INDIANA IS A SMALL PATCH OF SHOWERS IN BUTLER COUNTY.
BEHIND WHERE THIS ACTIVITY PASSED...THE AIR MASS IS QUITE
STABLE...WITH A NEAR-COMPLETE LACK OF CUMULUS DEVELOPMENT IN THE
SHADOW OF THE FORMER CONVECTIVE COMPLEX. ACROSS THE REST OF THE
CWA...CONDITIONS HAVE BECOME UNSTABLE...BUT THE CUMULUS FIELD HAS
REMAINED RATHER FLAT. WITH NOTHING IN THE WAY OF WELL-DEFINED
FORCING OVER THE REGION...THE FORECAST FOR THE REST OF THE DAY HAS
BEEN KEPT DRY. AT WORST...IT SEEMS LIKE PERHAPS A FEW BRIEF
SHOWERS COULD DEVELOP THROUGH THE EVENING...BUT WITH LITTLE
POTENTIAL FOR ANYTHING MORE THAN VERY ISOLATED COVERAGE.
OF GREATER CONCERN THROUGH EARLY TUESDAY MORNING IS THE POTENTIAL
FOR STORMS TO MOVE INTO THE NORTHWESTERN CWA FROM INDIANA. AN
INTENSE MCS HAS DEVELOPED IN IOWA...AND THERE IS LITTLE TO IMPEDE
ITS RAPID PROGRESS ACROSS NORTHERN ILLINOIS AND EVENTUALLY INTO
NORTHERN INDIANA. HIGH RESOLUTION MODELS...SUCH AS THE HRRR AND
WRF-ARW...DEPICT THAT THIS ACTIVITY WILL BE ON A WEAKENING TREND
AS IT PROGRESSES THROUGH INDIANA...PAST THE EDGE OF THE SPC MDT
RISK AREA. WESTERLY SHEAR AND INSTABILITY ARE FORECAST TO WEAKEN
WITH EASTWARD PROGRESS OF THE MCS...AND THE CONVERGENCE ALONG THE
LOW-LEVEL JET WILL LOSE ITS FOCUS. WHAT PROVIDES SOME CONCERN IS
THAT THE MOIST ENVIRONMENT WILL RETAIN ITS INSTABILITY HEADING
THROUGH THE OVERNIGHT HOURS. THUS...THERE APPEARS TO BE A
CONDITIONAL THREAT OF STORMS WITH STRONG WINDS MAKING IT INTO THE
NORTHWESTERN CWA SOME TIME AFTER 06Z.
THE CONTINUED SOUTHERLY FLOW WILL KEEP BOUNDARY LAYER MOISTURE
FAIRLY HIGH TONIGHT...RESULTING IN WARM MIN TEMPS IN THE LOWER 70S.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
IT SHOULD FIRST BE NOTED THAT THE ENTIRE SHORT TERM FORECAST MAY
END UP CONTINGENT ON WHAT HAPPENS TO THE MCS MOVING ACROSS THE
SOUTHERN GREAT LAKES ON MONDAY NIGHT INTO EARLY TUESDAY MORNING.
THIS MAY LEAD TO A FOCUS FOR ADDITIONAL STORM DEVELOPMENT LATER IN
THE DAY (IF IT WEAKENS AS FORECAST)...OR A STABILIZATION TO
CONDITIONS ACROSS THE ILN FORECAST AREA (IF IT HOLDS TOGETHER).
THOUGH THESE SCENARIOS REMAIN UNCERTAIN...THE FORECAST IS BEING
ASSEMBLED WITH THE ASSUMPTION THAT THE MONDAY NIGHT MCS WILL NOT
HAVE A LARGE DIRECT IMPACT ON TUESDAY CONDITIONS FOR THE MIDDLE
OHIO VALLEY.
SLIGHTLY STRONGER WESTERLY FLOW IN THE MID-LEVELS WILL BE MOVING
OVER THE REGION ON TUESDAY...WITH A WEAK SHORTWAVE FORECAST TO
PASS THROUGH THE AREA. THERE WILL ALSO BE A WEAK SURFACE
TROUGH...WHICH COULD COMBINE WITH ANY LEFTOVER BOUNDARIES FROM
MONDAY NIGHT TO ACT AS A FOCUS FOR CONVECTIVE DEVELOPMENT. THERE
IS ALSO A GRADIENT IN THETA-E WITH SOME DEPTH THROUGH THE LOWEST
FEW KILOMETERS. AHEAD OF THIS FEATURE...CONTINUED SOUTHWESTERLY
FLOW WILL SUPPORT INCREASING TEMPERATURES AND
DEWPOINTS...ESPECIALLY IN THE SOUTHEASTERN CWA. WITH EXPECTATIONS
OF MAX TEMPS IN THE LOWER 90S AND DEWPOINTS IN THE LOWER 70S...A
HEAT ADVISORY (HEAT INDEX OVER 100 DEGREES) WAS REQUIRED FOR A FEW
COUNTIES FOR TUESDAY AFTERNOON.
THIS ENVIRONMENT WILL ALSO BECOME VERY UNSTABLE...WITH LITTLE TO
NO CAPPING. MIXED LAYER CAPE VALUES OF 2000-3000 J/KG APPEAR
POSSIBLE...MAINLY SOUTH OF THE INTERSTATE 71 CORRIDOR. VALUES AS
HIGH AS 5000 J/KG WERE FORECAST ON THE NAM12...BUT THIS APPEARS TO
BE BASED ON AN ERRONEOUS UPPER-70S DEWPOINT FORECAST. SHEAR WILL
STILL BE MARGINAL...THOUGH INCREASING THROUGH THE AFTERNOON AND
EVENING (GETTING AS HIGH AS 30 KNOTS FROM 0-6KM). THIS IS
CERTAINLY ENOUGH TO ALLOW FOR A THREAT OF SEVERE WEATHER...WITH
LARGE HAIL AND DAMAGING WINDS BEING POSSIBLE. THE SPC DAY 2
OUTLOOK COVERS THE ENTIRE CWA...BUT THE THREAT SEEMS MARGINAL FOR
THE FAR NORTHWESTERN CWA...WHICH SEEMS MOST LIKELY TO BE IMPACTED
BY STABILIZATION FROM ANYTHING THAT MOVES THROUGH TUESDAY MORNING.
THE SOUTHEASTERN THIRD OF THE CWA WILL HAVE THE MOST INSTABILITY
AND FAVORABLE TIMING TO WORK WITH. ALTHOUGH THESE PARAMETERS
APPEAR FAVORABLE...IT IS INTERESTING TO NOTE THAT MOST MODEL
GUIDANCE (BOTH TRADITIONAL AND CONVECTIVE-ALLOWING) DOES NOT
GENERATE PARTICULARLY WIDESPREAD STORMS OR QPF...WHICH RAISES A
FEW QUESTIONS ABOUT EVENTUAL CONVECTIVE COVERAGE.
THE TEMPERATURE FORECAST BRINGS IN A LITTLE MORE A GRADIENT FOR
TUESDAY AND ESPECIALLY ON TUESDAY NIGHT...AS BOTH CONVECTION AND
THE WEAK FRONT MAKE THEIR WAY NW-TO-SE ACROSS THE REGION.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
MID LEVEL TROUGH WILL CONTINUE TO DIG SOUTHEAST INTO THE REGION ON
WEDNESDAY. WEAK SFC BOUNDARY NEAR OUR SE CWFA WILL BE SLOW TO MOVE
EAST THROUGH THE DAY WHILE A WEAK COLD FRONT APPROACHES THE REGION
FROM THE NORTHWEST. DESPITE SOME EMBEDDED ENERGY IN THE FLOW
ALOFT...LOW LEVEL FORCING IS WEAK...AND INSTABILITY WILL BE SOMEWHAT
LIMITED. HAVE GONE WITH CHANCE POPS PEAKING IN THE AFTERNOON HOURS.
HAVE RELEGATED THE THUNDER THREAT ALONG AND SE OF I-71 WHERE
INSTABILITY WILL BE THE GREATEST FOR THUNDER. TEMPERATURES WILL
RANGE FROM THE UPPER 70S NW TO THE MID 80S SE.
FOR WEDNESDAY NIGHT AND THURSDAY...LARGE SCALE MID LEVEL TROUGH
TRAVERSES THE GREAT LAKES AND OHIO VALLEY REGION. WEAK COLD FRONT
WILL SAG SOUTHEAST INTO THE REGION WEDNESDAY NIGHT AND THEN SOUTHEAST
OF THE AREA ON THURSDAY. WEAK LIFT WITH THE FRONT...AND SOME POST
FRONTAL SHALLOW INSTABILITY WILL KEEP LOW CHANCES FOR SHOWERS GOING.
THREAT FOR LIGHT SHOWERS ENDS BY THURSDAY EVENING AS DIURNALLY
DRIVEN CUMULUS CLOUDS WILL BEGIN TO THIN. HIGHS ON THURSDAY WILL BE
COOLER...MAINLY IN THE 70S.
FOR THURSDAY NIGHT INTO FRIDAY...LARGE SCALE MID LEVEL TROUGH IS
FORECAST TO PUSH INTO SE CANADA AND THE NEW ENGLAND REGION. THIS
WILL ALLOW FOR A LARGE SURFACE HIGH PRESSURE RIDGE TO SETTLE SOUTH
INTO THE GREAT LAKES AND OHIO VALLEY ON ITS BACK SIDE. ITS LOOKING
LIKE A DELIGHTFUL FOURTH OF JULY IF YOU LIKE LOW HUMIDITY AND HIGHS
RANGING FROM THE MID 70S TO NEAR 80 UNDER ABUNDANT SUNSHINE.
FOR FRIDAY NIGHT INTO SATURDAY...THE HIGH WILL REMAIN OVER THE GREAT
LAKES AND OHIO VALLEY. AIRMASS MODIFICATION WILL BOOST TEMPERATURES
INTO THE UPPER 70S TO THE LOWER 80S.
UPR LVL FLOW BEGINS TO DEAMPLIFY HEADING INTO THE FIRST PART OF NEXT
WEEK. THERE REMAINS DISAGREEMENT AMONG THE LONG RANGE MODELS AS TO
HOW FAST WEAK ENERGY IN THE WEST/NORTHWEST FLOW ALOFT WILL PROPAGATE
SOUTHEAST INTO THE OHIO VALLEY. MEANWHILE...SURFACE HIGH MOVES EAST
AND ALLOWS FOR A RETURN SOUTHERLY FLOW AND MORE SUMMER TIME
TEMPERATURES. WILL TRY TO KEEP SUNDAY DRY AND THEN ALLOW FOR CHANCE
POPS FOR SHOWERS/STORMS ON MONDAY AS AFOREMENTIONED WEAK ENERGY MAY
AFFECT US BY THEN.
&&
.AVIATION /20Z MONDAY THROUGH SATURDAY/...
STRATOCU UNDERNEATH AN INCREASING CI SHIELD HAVE NOT BEEN MIXED
OUT EARLY THIS AFTERNOON AS EXPECTED...AT LEAST NOT AS RAPIDLY.
THE WEAK BAND OF SHOWERS WITH EMBEDDED THUNDER IN CENTRAL INDIANA
WILL CONTINUE TO WEAKEN AND SHOULD ONLY BRIEFLY AFFECT KCVG/KLUK.
A CORE OF THE LEADING EDGE IS BEING PUSHED OUT OF THE MEAN SSEWD
PROPAGATION AND IS HEADING TOWARDS KCVG. WILL CONTINUE TO MONITOR
TAF SITES AND AMEND IF NECESSARY.
SC UNDER CI WILL CONTINUE TO THIN THIS AFTERNOON. CI SHIELD WILL
EXIT TO THE ENE OVERNIGHT AND SCT250 TO MAYBE CLEAR SKIES ARE
EXPECTED TOWARDS DAYBREAK. DAYTIME HEATING WILL POP SOME CU
TOMORROW AHEAD OF A COLD FRONT AND THIS FRONT WILL LIKELY BECOME A
BIT MORE ACTIVE WITH SHOWERS AND THUNDERSTORMS IN THE 18-0Z TIME
FRAME TOMORROW.
OUTLOOK...A FEW THUNDERSTORMS ARE POSSIBLE WEDNESDAY AND THURSDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...HEAT ADVISORY FROM 2 PM TO 8 PM EDT TUESDAY FOR OHZ081-082-088.
KY...HEAT ADVISORY FROM 2 PM TO 8 PM EDT TUESDAY FOR KYZ098>100.
IN...NONE.
&&
$$
SYNOPSIS...HATZOS
NEAR TERM...HATZOS
SHORT TERM...HATZOS
LONG TERM...HICKMAN
AVIATION...FRANKS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
348 PM EDT MON JUN 30 2014
.SYNOPSIS...
HIGH PRESSURE ALONG THE EAST COAST WILL MOVE OFFSHORE TONIGHT. A COLD
FRONT WILL MOVE ACROSS THE AREA ON TUESDAY. A SECONDARY COLD FRONT
WILL FOLLOW WEDNESDAY EVENING. DRY AND COOLER WEATHER WILL MOVE
IN BY FRIDAY AS A LARGE AREA OF CANADIAN HIGH PRESSURE BUILDS
ACROSS THE GREAT LAKES.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
MAIN QUESTION OVERNIGHT IS WHETHER CONVECTION DEVELOPING OVER
ILLINOIS WILL SPREAD EAST AND AFFECT NORTH OHIO AFTER MIDNIGHT.
THE SSEO AND MORE RECENT RUNS OF THE HRRR INDICATE THAT THE
CONVECTION WILL MOVE TOWARD THE REGION BUT WILL WEAKEN RAPIDLY
AFTER MIDNIGHT AS IT APPROACHES NW OHIO. DIURNAL TIMING DOES NOT
FAVOR THE PERSISTENCE OF THE CONVECTION BUT WE WILL CONTINUE THE
CHANCE OF STORMS IN THE THE NORTHWEST PORTION OF THE FORECAST AREA
ESPECIALLY NEAR TOL. ELSEWHERE A TRIGGER FOR CONVECTION IS
DIFFICULT TO DETERMINE AND POPS HAVE BEEN SET TO NEAR 15 PERCENT.
RATHER HIGH DEWPOINTS ALONG WITH WARM BOUNDARY LAYER TEMPERATURES
WILL HELP KEEP TEMPERATURES UP TONIGHT SO HAVE CONTINUED THE
FORECAST PREDICTION OF A LOW FROM 70 TO 75.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/...
VERY WARM AND HUMID CONDITIONS WILL BE REPLACED WITH MORE SEASONAL
WEATHER BY THE END OF THIS PERIOD. THE APPROACH AND PASSAGE OF A
COLD FRONT TUESDAY AFTERNOON WILL BE A TRIGGER FOR WIDESPREAD
CONVECTIVE DEVELOPMENT. MLCAPE WILL BE RATHER ELEVATED AND WIND
SHEAR WILL BE SUFFICIENT FOR ORGANIZED CONVECTIVE DEVELOPMENT
ESPECIALLY NEAR LAKE ERIE WHERE LAKE BREEZE BOUNDARIES AND ENHANCED
LOW LEVEL SHEAR WILL AID IN PRODUCING ROTATING STORMS.
VERY WARM 850 MB TEMPERATURES FROM 18-20C WOULD SUGGEST SURFACE
TEMPERATURES RISING TO NEAR 90 BUT CONVECTIVE DEVELOPMENT MAY
PREVENT MAX HEATING SO WILL CONTINUE THE FORECAST WITH THE
TEMPERATURES IN THE MID TO UPPER 80S.
LINGERING CONVECTION WILL MOVE OUT OF THE EASTERN COUNTIES TUESDAY EVENING.
THE MAIN TROUGH AXIS AND ITS ATTENDANT COLD FRONT WILL SHIFT EAST
AND CROSS THE REGION WEDNESDAY AND WEDNESDAY EVENING. SCATTERED
SHOWERS WITH A LITTLE THUNDER CAN BE EXPECTED BUT TIMING THE SMALL
SCALE FEATURES ARE DIFFICULT.
COOLER AND LESS HUMID CONDITIONS WILL PREVAIL ESPECIALLY BY THURSDAY.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
MODELS REMAIN IN GOOD AGREEMENT ON THE EXTENDED. MODELS CONTINUE
TO FORECAST LARGE AREA OF HIGH PRESSURE TO MOVE EAST ACROSS THE
LOWER GREAT LAKES OVER THE WEEKEND. THE ENTIRE WEEKEND SHOULD BE
DRY WITH TEMPERATURES STARTING OUT A LITTLE BELOW NORMAL...AND
GRADUALLY WARMING TO NEAR NORMAL BY SUNDAY. MODELS DIVERGE ON
MONDAY AS ECMWF MOVES THE RIDGE EAST AND ANOTHER FRONT SWEEPS ACROSS
THE GREAT LAKES. THE GFS ON THE OTHER HAND MAINTAINS THE RIDGE
THROUGH MONDAY. FOR NOW WILL SPIT THE DIFFERENCE AND LEAN TOWARD
CONTINUITY AND GO SLIGHT CHANCE POPS.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
SCT TO BKN CU FIELD AT 2500-3500 FT OR HIGHER WILL GRADUALLY
DIMINISH AFTER SUNSET. HOWEVER...CLOUDS WILL GRADUALLY THICKEN AND
LOWER FROM THE WEST OVERNIGHT. EXPECT WIDESPREAD MARGINAL
CONDITIONS BY DAYBREAK TUESDAY.
THERE IS ONLY A MINIMAL CHANCE FOR TSRA THIS AFTERNOON AND
EVENING SO WILL KEEP OUT OF THE TAFS. A NEW BAND OF CONVECTION
WITH MAY BE MOVING NEAR TOL BY 12Z TUE. BETTER CHANCE OF
CONVECTION EAST HALF TOMORROW AFTERNOON.
OUTLOOK...NON VFR IN SHOWERS AND THUNDERSTORMS LATE TUESDAY THROUGH
THURSDAY.
&&
.MARINE...
SOUTH TO SSW WINDS SHOULD GENERALLY CONTINUE...THEN TURN TO THE WEST
TUESDAY AS THE FIRST OF A SERIES OF FRONTS MOVES ACROSS LAKE ERIE.
CONDITIONS WILL BECOME CHOPPY ON THE LAKE TUESDAY EVENING...BUT
SHOULD REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA. THE SECOND COLD
FRONT WILL MOVE SE ACROSS THE LAKE WED TURNING THE WINDS NW BUT WIND
SPEEDS WILL ALSO BE GRADUALLY DECREASING TO 5 TO 15 KNOTS AS THE
WEATHER SYSTEMS WEAKEN. HIGH PRESSURE MOVES OVER THE LAKE FRI TO
CALM THE WINDS FOR FRI NIGHT.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LAPLANTE
NEAR TERM...LAPLANTE
SHORT TERM...LAPLANTE
LONG TERM...DJB
AVIATION...DJB
MARINE...DJB
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1229 PM CDT MON JUN 30 2014
.DISCUSSION...
UPDATED FOR THE 18Z AVIATION DISCUSSION
&&
.PREV DISCUSSION... /ISSUED 1026 AM CDT MON JUN 30 2014/
UPDATE...MORNING UPDATE.
DISCUSSION...
TEMPERATURES ARE WARMING QUICKLY ACROSS THE MIDSOUTH ALTHOUGH SOME
THIN STRATUS IS PROBABLY HELPING TO KEEP CONDITIONS SLIGHTLY
COOLER THAN WHAT THEY COULD BE. ABUNDANT GROUND MOISTURE IS
RESULTING IN HIGH HUMIDITY...AND ENHANCED HEAT INDICES.
TEMPERATURES WILL LIKELY TOP OUT IN THE LOW TO MIDDLE 90S THIS
AFTERNOON WITH HEAT INDICES AROUND 100. NO RAIN IS EXPECTED.
PREV DISCUSSION... /ISSUED 621 AM CDT MON JUN 30 2014/
CURRENTLY...A WEAK LEFTOVER BOUNDARY STRETCHES NW/SE ACROSS WEST
TENNESSEE THIS MORNING. THE HRRR HAS BEEN TRYING TO DEVELOP
CONVECTION INVOF THIS BOUNDARY OVERNIGHT BUT THE 850 MB FLOW OF
15-20 KTS DOES NOT SEEM TO BE ENOUGH TO GENERATE ANY CONVECTION
WEST OF THE TN RIVER. SKIES RANGE FROM MOSTLY CLEAR IN THE WEST TO
MOSTLY CLOUDY NEAR THE TN RIVER. VERY MOIST AND WARM ACROSS THE
DELTA WHERE DEWPOINTS ARE IN THE MID 70S.
TODAY...WILL LEAVE A SMALL POPS ALONG THE TN RIVER VALLEY THIS
MORNING TO COVER ANY POTENTIAL DEVELOPMENT. THE BIG STORY TODAY IS
THE UPPER RIDGE BUILDING INTO THE AREA WITH INCREASINGLY HOT AND
HUMID CONDITIONS. EXPECT DEWPOINTS TO REMAIN QUITE HIGH TODAY DUE
TO ALL THE RECENT RAINS. THE 00Z NAM IS A LITTLE LESS AGGRESSIVE
WITH 925 MB TEMPS THAN PREVIOUS RUNS SO BACKED OFF HIGHS ABOUT A
DEGREE. THE ADDED LOW LEVEL MOISTURE DUE TO RECENT RAIN WILL MAKE
UP FOR IT AS DEWPOINTS WILL REMAIN IN THE MID 70S THIS MORNING
BEFORE MIXING OUT A BIT THIS AFTERNOON. HEAT INDEX VALUES WILL HIT
100F BY ABOUT NOON.
TONIGHT...WARM AND MUGGY WITH MOSTLY CLEAR SKIES. LOWS WILL BE IN
THE LOWER TO MID 70S.
TUESDAY...ANOTHER HOT AND HUMID DAY. TEMPS WILL CLIMB A COUPLE
DEGREES HIGHER PUSHING HEAT INDEX VALUES IN THE LOW 100S WITH
PLENTY OF SUNSHINE. AN UPPER TROF PUSHING THROUGH THE GREAT LAKES
WILL PUSH A COLD FRONT TOWARD THE MIDSOUTH IN THE AFTERNOON
PERHAPS BRINGING SOME SHOWERS AND THUNDERSTORMS TO NORTHERN
LOCATIONS. THE AIRMASS WILL BE QUITE UNSTABLE AND A FEW STRONG
STORMS ARE POSSIBLE ACROSS THE NORTH.
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...00Z MODELS INDICATE THE
GREAT LAKES TROF WILL BE A LITTLE DEEPER AND EXTEND A LITTLE
FURTHER INTO THE SOUTHERN STATES BY WEDNESDAY WHICH HELPS DRIVE
THE FRONT THROUGH MORE QUICKLY ON WEDNESDAY. SHOWER/THUNDERSTORM
CHANCES WILL MOVE SOUTH TUESDAY NIGHT AND WEDNESDAY WITH THE
FRONT. BY WEDNESDAY EVENING MOST OF THE PRECIP WILL HAVE EXITED
THE REGION. MODELS ARE INDICATING A GOOD DEAL OF INSTABILITY
ACROSS THE AREA THOUGH WIND SHEAR IS FAIRLY WEAK AT THE SOUTHERN
END OF THE UPPER TROF. A FEW STRONG STORMS ARE POSSIBLE ACROSS THE
AREA AS THE FRONT MOVES THROUGH.
THURSDAY THROUGH SUNDAY...HIGH PRESSURE INTO THE AREA ON THURSDAY
AND CONTINUE INTO THE WEEKEND. BELOW NORMAL TEMPERATURES ARE
EXPECTED WITH HIGHS IN THE 80S THURSDAY AND FRIDAY AND LOWS IN THE
60S. MAY EVEN SEE SOME 50S IN THE TYPICAL COOLER SPOTS. TEMPS WILL
BEGIN TO WARM BACK INTO THE LOWER 90S BY SUNDAY.
SJM
&&
.AVIATION...
18Z TAF CYCLE
CURRENT MVFR CEILINGS AT KJBR SHOULD END SOON OTHERWISE VFR
CONDITIONS SHOULD PERSIST FOR MUCH OF THE FORECAST PERIOD. WINDS
WILL BE MAINLY FROM THE SOUTHWEST AT 10 TO 15 KNOTS THIS AFTERNOON
BEFORE DIMINISHING TO 5 TO 10 KNOTS TONIGHT. WINDS WILL INCREASE
BACK TO 10 TO 15 KNOTS TUESDAY MORNING.
ARS
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS GREEN BAY WI
516 PM CDT MON JUN 30 2014
NEW INFORMATION ADDED TO UPDATE SECTION
.UPDATE...
ISSUED AT 508 PM CDT MON JUN 30 2014
CLUSTER OF STRONGER STORMS LIFTG NE ACRS COLUMBIA COUNTY LOOKS TO
BE HEADED FOR MANITOWOC COUNTY. THAT COULD BRING A SVR RISK TO THE
FAR SE PART OF THE FCST AREA. THE MAIN BOOKEND VORTEX WITH THE
BOW REMAINS ON A TRAJECTORY TO STAY S OF THE AREA.
PARAMETERS LOOK FAVORABLE FOR 35-40 KT WAKE-LOW WIND GUSTS
GETTING INTO THE SW PART OF THE FCST AREA. PLAN TO HANDLE WITH SPS
AND GRIDS/MAIN FCST PRODUCTS FOR NOW. MAX WIND GUSTS WL OCCUR
RIGHT AT THE BACK EDGE OF THE RAIN...WHERE THE SHARP REFLECTIVITY
GRADIENT IS LOCATED.
UPDATE
ISSUED AT 408 PM CDT MON JUN 30 2014
OVERALL CONVECTIVE EVOLUTION FOR THE LATE AFTN AND EVENING HAS
BECOME APPARENT. DERECHO PRODUCING MCS WL RACE EWD ACRS SRN WI/NRN
IL WITH WIDESPREAD DAMAGING WINDS AND ISOLD TORNADOES. CLEARLY
THE BRUNT OF THIS SYSTEM WL PASS TO OUR S. MAIN CONCERNS NOW ARE
WHETHER OR NOT E-C WI GETS NICKED BY THE NRN END OF THE
SYSTEM...AND THE POTENTIAL FOR WAKE- OW INDUCED WIND GUSTS BEHIND
THE CONVECTIVE SYSTEM.
RECENT HRRR RUNS AS WELL AS FORWARD PROPAGATING CORFIDI VECTORS
OVERLAYED ON CURRENT RADAR MOSAIC SUGGEST MAIN BOOKEND VORTEX ON
THE NRN END OF THE LARGE BOW SHOULD TURN NEWD AND MV/EVOLVE TOWARD
THE SERN PART OF THE FCST AREA. BUT THIS HAS YET TO HAPPEN. UNLESS
A TURN TO THE NE OCCURS SOON...IT WL BE TOO LATE TO BRING THE
STG/SVR PORTION OF THE MCS INTO THE FCST AREA.
SECOND CONCERN IS WAKE-LOW INDUCED WIND GUSTS. THE NEAREST OF
THOSE THUS FAR HAVE BEEN ACRS NERN IA. THOSE TYPICALLY DEVELOP
RIGHT AT THE BACK EDGE OF THE PCPN...WHEN THE TRAILING PORTION OF
THE PCPN STARTS TO RAPIDLY DISSIPATE. WL BE WATCHING TO SEE
WHETHER ANY OF THOSE TRENDS LOOK LIKE THEY ARE WORKING TOWARD THE
FCST AREA LATE THIS AFTN/THIS EVENING.
ELSEHWERE...DEEP MIXING INTO STRONGER WINDS ALOFT RESULTED IN
GUSTY WINDS AND A FEW POWER OUTAGES OVER N-C WI. HANDLED THOSE BY
BUMPING UP WINDS IN THE FCST...AND NOW THAT MID/HIGH CLD SHIELD
HAS OVERSPREAD THE AREA...THE WINDS SHOULD SETTLE DOWN A BIT.
&&
.SHORT TERM...TONIGHT AND TUESDAY
ISSUED AT 330 PM CDT MON JUN 30 2014
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A COMPLEX
WEATHER EVOLUTION UNFOLDING OVER THE WESTERN GREAT LAKES. OCCLUDED
FRONT OR MOISTURE DISCONTINUITY EXTENDS FROM THE CENTRAL UPPER
PENINSULA TO SOUTHWEST IOWA. BEHIND THIS BOUNDARY...DEWPOINTS HAVE
FALLEN INTO THE MIDDLE 40S TO MIDDLE 50S WITH NEAR RED FLAG
CONDITIONS OVER N-C WISCONSIN. AHEAD OF THIS BOUNDARY WHERE
DEWPOINTS ARE IN THE UPPER 60S TO LOWER 70S...CONVECTION HAS YET TO
FIRE OVER CENTRAL AND NORTHEAST WISCONSIN. THE 18Z GRB SOUNDING
SHOWED TEMPERATURES HAVE WARMED BETWEEN 750-550MB...RESULTING IN A
CAP OF AROUND 60 J/KG...THOUGH ML CAPES ARE GREATER THAN 1500 J/KG.
LIGHT RAIN HAS PUSHED INTO CENTRAL WISCONSIN AHEAD OF A POTENT MCS
THAT DEVELOPED EARLIER TODAY OVER WESTERN IOWA. THIS MCS HAS SHOWN
NO SIGNS OF LIFTING NORTHEAST DESPITE A POTENT SHORTWAVE DIGGING
SOUTH OVER THE NORTHERN PLAINS. AS THE FRONT AND MCS MOVE
EAST...SEVERE WEATHER CHANCES ARE THE MAIN FORECAST CONCERNS.
FOR THE REST OF THIS AFTERNOON...HEIGHT FALLS AHEAD OF THE MCS AND
SHORTWAVE FARTHER WEST MAY HELP TO REDUCE THE CAP OVER NORTHEAST
WISCONSIN. IF THE MCS STARTS A MORE NE TRACK DUE TO BACKING WIND
FIELDS ALOFT...ASCENT WILL SUPPORT THUNDERSTORM DEVELOPMENT OVER
PARTS OF CENTRAL AND EAST-CENTRAL WISCONSIN OVER THE NEXT FEW
HOURS. BUT ITS STILL NOT CLEAR IF THIS NE TRACK WILL OCCUR OR
THUNDERSTORMS COULD FORM BEFORE LIGHT RAIN ON THE NORTHERN EDGE OF
THE MCS ARRIVES. BEST CHANCES FOR THUNDERSTORM DEVELOPMENT WOULD BE
SOUTH OF A LINE FROM WAUTOMA TO GREEN BAY TO ALGOMA. ANY
THUNDERSTORMS WOULD BRING THE THREAT OF LARGE HAIL AND DAMAGING
WINDS. BUT ITS STARTING TO LOOK LIKE THE SEVERE THREAT WILL BE
CONFINED TO SOUTHERN WISCONSIN AND POINTS SOUTH. WILL HAVE TO KEEP
A MENTION OF SEVERE WEATHER...BUT CONFIDENCE HAS LOWERED TO THE DAY.
TONIGHT...FOLLOWING THE LEAD OF THE GFS AND HRRR...HEIGHT FALLS OVER
THE NORTHERN PLAINS SHOULD PROMOTE THE MCS OVER SOUTHERN MINNESOTA
AND IOWA TRACKING ENE ACROSS NORTHERN ILLINOIS AND SOUTHERN
WISCONSIN THIS EVENING. IF LIGHT RAIN DOES NOT EXTEND INTO AREAS
FROM WAUTOMA TO GREEN BAY TO ALGOMA THIS AFTERNOON...HEIGHT FALLS
AHEAD OF THE MCS COULD BE ENOUGH TO WEAKEN THE CAP LATE THIS
AFTERNOON INTO EARLY THIS EVENING TO PRODUCE SEVERE WEATHER IN THIS
CORRIDOR. UNCERTAINTY REMAINS HIGH THAT THIS WILL OCCUR AS
INSTABILITY IS CONSIDERABLY HIGHER OVER SOUTHERN PARTS OF THE
STATE...AND THE STRONGEST CONVECTION USUALLY FOLLOWS THE HIGHER
INSTABILITY. DUE TO THE STRONG WIND FIELDS ALOFT (45-55KTS OF 0-6KM
BULK SHEAR)...WILL HAVE TO KEEP THE POTENTIAL FOR SEVERE WEATHER IN
THE FORECAST UNTIL LATE EVENING...THOUGH FEELING IS THAT MOST OF THE
SEVERE WEATHER WILL REMAIN OVER SOUTHERN WISCONSIN. ISOLATED
COVERAGE REMAINS POSSIBLE OVER FAR NE WISCONSIN ASSUMING THE LIGHT
RAIN DOES NOT HOLD TOGETHER TO MAKE IT INTO THIS AREA. THE MAIN
THREATS WITH ANY CONVECTION WILL BE LARGE HAIL AND DAMAGING
WINDS...ALONG WITH THE POTENTIAL FOR HEAVY RAIN THOUGH THIS SHOULD
BE CONFINE TO THE WAUTOMA TO ALGOMA AREAS. ONCE THE PRECIP EXITS NE
WISCONSIN BY LATE IN THE EVENING...DRY SLOTTING SHOULD BRING
CLEARING SKIES FOR A SEVERAL HOUR PERIOD. THEN LOW STRATUS WILL
APPROACH N-C WISCONSIN LATE TONIGHT AS COLDER AIR FILTERS IN FROM
THE NORTHWEST. LOWS IN THE UPPER 50S TO MIDDLE 60S.
TUESDAY...UPPER TROUGHING WILL MOVE INTO THE WESTERN GREAT LAKES
WHICH WILL PROMOTE LOW LEVEL MOISTURE SURGING SOUTHEAST ACROSS THE
REGION. WITH DAYTIME INSTABILITY...CYCLONIC FLOW WILL SUPPORT
SHOWER DEVELOPMENT WHICH SHOULD HAVE GREATER COVERAGE OVER THE
HIGHER ELEVATION AREAS OF CENTRAL AND NORTH-CENTRAL WISCONSIN. HAVE
INCREASED PRECIP CHANCES INTO THE LIKELY RANGE DURING THE
AFTERNOON. HIGHS RANGING FROM THE UPPER 60S NORTH TO THE MIDDLE 70S
SOUTH.
.LONG TERM...TUESDAY NIGHT THROUGH MONDAY
ISSUED AT 330 PM CDT MON JUN 30 2014
MAIN FOCUS ON SHORT-TERM SEVERE/HEAVY RAINFALL THREAT THIS AFTERNOON
AND EVENING...SO WILL BE BRIEF WITH EXTENDED FCST DISCUSSION. MAIN
CONCERNS ARE LOW-END PCPN THREATS...AND A RETURN TO COOLER THAN
NORMAL TEMPS FOR A FEW DAYS.
AN UPPER LEVEL TROF AND CYCLONIC NW FLOW AT THE SFC WILL COMBINE
TO PRODUCE SCT SHOWERS OVER THE FORECAST AREA INTO MIDWEEK. CAA
AND CLOUD COVER WILL RESULT IN THE COOLEST DAY OF THE WEEK ON
WEDNESDAY...WITH HIGHS IN THE MID 60S TO LOWER 70S.
CANADIAN HIGH PRESSURE WILL RESIDE OVER THE WESTERN GREAT LAKES
REGION ON THURSDAY AND FRIDAY (4TH OF JULY)...BRINGING ABUNDANT
SUNSHINE...LOW HUMIDITY AND PLEASANT TEMPS IN THE LOWER TO MIDDLE
70S. THE WEATHER SHOULD BE PERFECT FOR 4TH OF JULY FIREWORKS
DISPLAYS.
THE SFC HIGH IS EXPECTED TO GRADUALLY SHIFT EAST DURING THE
WEEKEND...WITH RETURN FLOW ALLOWING A SMALL CHANCE OF SHOWERS
AND THUNDERSTORMS TO RETURN TO THE REGION. MOST MEDIUM-RANGE
MODELS SUGGEST THAT THE MAIN BRUNT OF THE PCPN WILL REMAIN
FOCUSED NEAR A WARM FRONT OVER IOWA AND NORTHERN IL OVER
THE WEEKEND...SO 20-30 POPS SHOULD COVER THE SITUATION.
TEMPERATURES WILL RETURN TO NORMAL LEVELS FOR EARLY JULY.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1159 AM CDT MON JUN 30 2014
SCT TO BKN MVFR CIGS WILL ENCOMPASS MUCH OF THE REGION
IN A HUMID AIRMASS EXCLUDING AREAS OVER FAR NORTH-CENTRAL WISCONSIN
WHERE DRIER AIR IS PRESENT. FOCUS OVER THE NEXT 12 HOURS IS THE
SHOWER AND THUNDERSTORM TIMING. LARGE CLUSTER OF SHOWERS AND STORMS
OVER SOUTHERN MINNESOTA AND IOWA WILL TRANSLATE EAST THIS AFTERNOON
AND ARE EXPECTED TO MOVE INTO CENTRAL WISCONSIN SHORTLY AFTER 18Z
AND EAST-CENTRAL WISCONSIN AFTER 20Z OR 21Z. ISOLATED STORMS ARE
EXPECTED TO FIRE NORTH OF THIS TRACK AND COULD BECOME STRONG TO
SEVERE. A BETTER CHANCE OF SEVERE STORMS WILL OCCUR FROM WAUTOMA TO
ALGOMA BETWEEN 21 AND 03Z AND LARGE HAIL/DAMAGING WINDS WILL BE THE
MAIN THREATS. STORMS WILL EXIT THE REGION BY MID TO LATE EVENING AS
COOLER AND DRIER AIR MOVES INTO THE STATE. A LARGE AREA OF STRATUS
WITHIN THIS COOLER AIRMASS IS EXPECTED TO ARRIVE TUESDAY MORNING AND
WILL LIKELY BRING SHOWER ACTIVITY TO MUCH OF THE REGION BY MIDDAY.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
BEACH HAZARDS STATEMENT UNTIL 9 PM CDT THIS EVENING FOR WIZ022.
&&
$$
UPDATE.........SKOWRONSKI
SHORT TERM.....MPC
LONG TERM......KIECKBUSCH
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
420 PM CDT MON JUN 30 2014
NEW INFORMATION ADDED TO UPDATE SECTION
.UPDATE...
ISSUED AT 408 PM CDT MON JUN 30 2014
OVERALL CONVECTIVE EVOLUTION FOR THE LATE AFTN AND EVENING HAS
BECOME APPARENT. DERECHO PRODUCING MCS WL RACE EWD ACRS SRN WI/NRN
IL WITH WIDESPREAD DAMAGING WINDS AND ISOLD TORNADOES. CLEARLY
THE BRUNT OF THIS SYSTEM WL PASS TO OUR S. MAIN CONCERNS NOW ARE
WHETHER OR NOT E-C WI GETS NICKED BY THE NRN END OF THE
SYSTEM...AND THE POTENTIAL FOR WAKE- OW INDUCED WIND GUSTS BEHIND
THE CONVECTIVE SYSTEM.
RECENT HRRR RUNS AS WELL AS FORWARD PROPAGATING CORFIDI VECTORS
OVERLAYED ON CURRENT RADAR MOSAIC SUGGEST MAIN BOOKEND VORTEX ON
THE NRN END OF THE LARGE BOW SHOULD TURN NEWD AND MV/EVOLVE TOWARD
THE SERN PART OF THE FCST AREA. BUT THIS HAS YET TO HAPPEN. UNLESS
A TURN TO THE NE OCCURS SOON...IT WL BE TOO LATE TO BRING THE
STG/SVR PORTION OF THE MCS INTO THE FCST AREA.
SECOND CONCERN IS WAKE-LOW INDUCED WIND GUSTS. THE NEAREST OF
THOSE THUS FAR HAVE BEEN ACRS NERN IA. THOSE TYPICALLY DEVELOP
RIGHT AT THE BACK EDGE OF THE PCPN...WHEN THE TRAILING PORTION OF
THE PCPN STARTS TO RAPIDLY DISSIPATE. WL BE WATCHING TO SEE
WHETHER ANY OF THOSE TRENDS LOOK LIKE THEY ARE WORKING TOWARD THE
FCST AREA LATE THIS AFTN/THIS EVENING.
ELSEHWERE...DEEP MIXING INTO STRONGER WINDS ALOFT RESULTED IN
GUSTY WINDS AND A FEW POWER OUTAGES OVER N-C WI. HANDLED THOSE BY
BUMPING UP WINDS IN THE FCST...AND NOW THAT MID/HIGH CLD SHIELD
HAS OVERSPREAD THE AREA...THE WINDS SHOULD SETTLE DOWN A BIT.
&&
.SHORT TERM...TONIGHT AND TUESDAY
ISSUED AT 330 PM CDT MON JUN 30 2014
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A COMPLEX
WEATHER EVOLUTION UNFOLDING OVER THE WESTERN GREAT LAKES. OCCLUDED
FRONT OR MOISTURE DISCONTINUITY EXTENDS FROM THE CENTRAL UPPER
PENINSULA TO SOUTHWEST IOWA. BEHIND THIS BOUNDARY...DEWPOINTS HAVE
FALLEN INTO THE MIDDLE 40S TO MIDDLE 50S WITH NEAR RED FLAG
CONDITIONS OVER N-C WISCONSIN. AHEAD OF THIS BOUNDARY WHERE
DEWPOINTS ARE IN THE UPPER 60S TO LOWER 70S...CONVECTION HAS YET TO
FIRE OVER CENTRAL AND NORTHEAST WISCONSIN. THE 18Z GRB SOUNDING
SHOWED TEMPERATURES HAVE WARMED BETWEEN 750-550MB...RESULTING IN A
CAP OF AROUND 60 J/KG...THOUGH ML CAPES ARE GREATER THAN 1500 J/KG.
LIGHT RAIN HAS PUSHED INTO CENTRAL WISCONSIN AHEAD OF A POTENT MCS
THAT DEVELOPED EARLIER TODAY OVER WESTERN IOWA. THIS MCS HAS SHOWN
NO SIGNS OF LIFTING NORTHEAST DESPITE A POTENT SHORTWAVE DIGGING
SOUTH OVER THE NORTHERN PLAINS. AS THE FRONT AND MCS MOVE
EAST...SEVERE WEATHER CHANCES ARE THE MAIN FORECAST CONCERNS.
FOR THE REST OF THIS AFTERNOON...HEIGHT FALLS AHEAD OF THE MCS AND
SHORTWAVE FARTHER WEST MAY HELP TO REDUCE THE CAP OVER NORTHEAST
WISCONSIN. IF THE MCS STARTS A MORE NE TRACK DUE TO BACKING WIND
FIELDS ALOFT...ASCENT WILL SUPPORT THUNDERSTORM DEVELOPMENT OVER
PARTS OF CENTRAL AND EAST-CENTRAL WISCONSIN OVER THE NEXT FEW
HOURS. BUT ITS STILL NOT CLEAR IF THIS NE TRACK WILL OCCUR OR
THUNDERSTORMS COULD FORM BEFORE LIGHT RAIN ON THE NORTHERN EDGE OF
THE MCS ARRIVES. BEST CHANCES FOR THUNDERSTORM DEVELOPMENT WOULD BE
SOUTH OF A LINE FROM WAUTOMA TO GREEN BAY TO ALGOMA. ANY
THUNDERSTORMS WOULD BRING THE THREAT OF LARGE HAIL AND DAMAGING
WINDS. BUT ITS STARTING TO LOOK LIKE THE SEVERE THREAT WILL BE
CONFINED TO SOUTHERN WISCONSIN AND POINTS SOUTH. WILL HAVE TO KEEP
A MENTION OF SEVERE WEATHER...BUT CONFIDENCE HAS LOWERED TO THE DAY.
TONIGHT...FOLLOWING THE LEAD OF THE GFS AND HRRR...HEIGHT FALLS OVER
THE NORTHERN PLAINS SHOULD PROMOTE THE MCS OVER SOUTHERN MINNESOTA
AND IOWA TRACKING ENE ACROSS NORTHERN ILLINOIS AND SOUTHERN
WISCONSIN THIS EVENING. IF LIGHT RAIN DOES NOT EXTEND INTO AREAS
FROM WAUTOMA TO GREEN BAY TO ALGOMA THIS AFTERNOON...HEIGHT FALLS
AHEAD OF THE MCS COULD BE ENOUGH TO WEAKEN THE CAP LATE THIS
AFTERNOON INTO EARLY THIS EVENING TO PRODUCE SEVERE WEATHER IN THIS
CORRIDOR. UNCERTAINTY REMAINS HIGH THAT THIS WILL OCCUR AS
INSTABILITY IS CONSIDERABLY HIGHER OVER SOUTHERN PARTS OF THE
STATE...AND THE STRONGEST CONVECTION USUALLY FOLLOWS THE HIGHER
INSTABILITY. DUE TO THE STRONG WIND FIELDS ALOFT (45-55KTS OF 0-6KM
BULK SHEAR)...WILL HAVE TO KEEP THE POTENTIAL FOR SEVERE WEATHER IN
THE FORECAST UNTIL LATE EVENING...THOUGH FEELING IS THAT MOST OF THE
SEVERE WEATHER WILL REMAIN OVER SOUTHERN WISCONSIN. ISOLATED
COVERAGE REMAINS POSSIBLE OVER FAR NE WISCONSIN ASSUMING THE LIGHT
RAIN DOES NOT HOLD TOGETHER TO MAKE IT INTO THIS AREA. THE MAIN
THREATS WITH ANY CONVECTION WILL BE LARGE HAIL AND DAMAGING
WINDS...ALONG WITH THE POTENTIAL FOR HEAVY RAIN THOUGH THIS SHOULD
BE CONFINE TO THE WAUTOMA TO ALGOMA AREAS. ONCE THE PRECIP EXITS NE
WISCONSIN BY LATE IN THE EVENING...DRY SLOTTING SHOULD BRING
CLEARING SKIES FOR A SEVERAL HOUR PERIOD. THEN LOW STRATUS WILL
APPROACH N-C WISCONSIN LATE TONIGHT AS COLDER AIR FILTERS IN FROM
THE NORTHWEST. LOWS IN THE UPPER 50S TO MIDDLE 60S.
TUESDAY...UPPER TROUGHING WILL MOVE INTO THE WESTERN GREAT LAKES
WHICH WILL PROMOTE LOW LEVEL MOISTURE SURGING SOUTHEAST ACROSS THE
REGION. WITH DAYTIME INSTABILITY...CYCLONIC FLOW WILL SUPPORT
SHOWER DEVELOPMENT WHICH SHOULD HAVE GREATER COVERAGE OVER THE
HIGHER ELEVATION AREAS OF CENTRAL AND NORTH-CENTRAL WISCONSIN. HAVE
INCREASED PRECIP CHANCES INTO THE LIKELY RANGE DURING THE
AFTERNOON. HIGHS RANGING FROM THE UPPER 60S NORTH TO THE MIDDLE 70S
SOUTH.
.LONG TERM...TUESDAY NIGHT THROUGH MONDAY
ISSUED AT 330 PM CDT MON JUN 30 2014
MAIN FOCUS ON SHORT-TERM SEVERE/HEAVY RAINFALL THREAT THIS AFTERNOON
AND EVENING...SO WILL BE BRIEF WITH EXTENDED FCST DISCUSSION. MAIN
CONCERNS ARE LOW-END PCPN THREATS...AND A RETURN TO COOLER THAN
NORMAL TEMPS FOR A FEW DAYS.
AN UPPER LEVEL TROF AND CYCLONIC NW FLOW AT THE SFC WILL COMBINE
TO PRODUCE SCT SHOWERS OVER THE FORECAST AREA INTO MIDWEEK. CAA
AND CLOUD COVER WILL RESULT IN THE COOLEST DAY OF THE WEEK ON
WEDNESDAY...WITH HIGHS IN THE MID 60S TO LOWER 70S.
CANADIAN HIGH PRESSURE WILL RESIDE OVER THE WESTERN GREAT LAKES
REGION ON THURSDAY AND FRIDAY (4TH OF JULY)...BRINGING ABUNDANT
SUNSHINE...LOW HUMIDITY AND PLEASANT TEMPS IN THE LOWER TO MIDDLE
70S. THE WEATHER SHOULD BE PERFECT FOR 4TH OF JULY FIREWORKS
DISPLAYS.
THE SFC HIGH IS EXPECTED TO GRADUALLY SHIFT EAST DURING THE
WEEKEND...WITH RETURN FLOW ALLOWING A SMALL CHANCE OF SHOWERS
AND THUNDERSTORMS TO RETURN TO THE REGION. MOST MEDIUM-RANGE
MODELS SUGGEST THAT THE MAIN BRUNT OF THE PCPN WILL REMAIN
FOCUSED NEAR A WARM FRONT OVER IOWA AND NORTHERN IL OVER
THE WEEKEND...SO 20-30 POPS SHOULD COVER THE SITUATION.
TEMPERATURES WILL RETURN TO NORMAL LEVELS FOR EARLY JULY.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1159 AM CDT MON JUN 30 2014
SCT TO BKN MVFR CIGS WILL ENCOMPASS MUCH OF THE REGION
IN A HUMID AIRMASS EXCLUDING AREAS OVER FAR NORTH-CENTRAL WISCONSIN
WHERE DRIER AIR IS PRESENT. FOCUS OVER THE NEXT 12 HOURS IS THE
SHOWER AND THUNDERSTORM TIMING. LARGE CLUSTER OF SHOWERS AND STORMS
OVER SOUTHERN MINNESOTA AND IOWA WILL TRANSLATE EAST THIS AFTERNOON
AND ARE EXPECTED TO MOVE INTO CENTRAL WISCONSIN SHORTLY AFTER 18Z
AND EAST-CENTRAL WISCONSIN AFTER 20Z OR 21Z. ISOLATED STORMS ARE
EXPECTED TO FIRE NORTH OF THIS TRACK AND COULD BECOME STRONG TO
SEVERE. A BETTER CHANCE OF SEVERE STORMS WILL OCCUR FROM WAUTOMA TO
ALGOMA BETWEEN 21 AND 03Z AND LARGE HAIL/DAMAGING WINDS WILL BE THE
MAIN THREATS. STORMS WILL EXIT THE REGION BY MID TO LATE EVENING AS
COOLER AND DRIER AIR MOVES INTO THE STATE. A LARGE AREA OF STRATUS
WITHIN THIS COOLER AIRMASS IS EXPECTED TO ARRIVE TUESDAY MORNING AND
WILL LIKELY BRING SHOWER ACTIVITY TO MUCH OF THE REGION BY MIDDAY.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
BEACH HAZARDS STATEMENT UNTIL 9 PM CDT THIS EVENING FOR WIZ022.
&&
$$
UPDATE.........SKOWRONSKI
SHORT TERM.....MPC
LONG TERM......KIECKBUSCH
AVIATION.......MPC
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND TUESDAY
ISSUED AT 330 PM CDT MON JUN 30 2014
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A COMPLEX
WEATHER EVOLUTION UNFOLDING OVER THE WESTERN GREAT LAKES. OCCLUDED
FRONT OR MOISTURE DISCONTINUITY EXTENDS FROM THE CENTRAL UPPER
PENINSULA TO SOUTHWEST IOWA. BEHIND THIS BOUNDARY...DEWPOINTS HAVE
FALLEN INTO THE MIDDLE 40S TO MIDDLE 50S WITH NEAR RED FLAG
CONDITIONS OVER N-C WISCONSIN. AHEAD OF THIS BOUNDARY WHERE
DEWPOINTS ARE IN THE UPPER 60S TO LOWER 70S...CONVECTION HAS YET TO
FIRE OVER CENTRAL AND NORTHEAST WISCONSIN. THE 18Z GRB SOUNDING
SHOWED TEMPERATURES HAVE WARMED BETWEEN 750-550MB...RESULTING IN A
CAP OF AROUND 60 J/KG...THOUGH ML CAPES ARE GREATER THAN 1500 J/KG.
LIGHT RAIN HAS PUSHED INTO CENTRAL WISCONSIN AHEAD OF A POTENT MCS
THAT DEVELOPED EARLIER TODAY OVER WESTERN IOWA. THIS MCS HAS SHOWN
NO SIGNS OF LIFTING NORTHEAST DESPITE A POTENT SHORTWAVE DIGGING
SOUTH OVER THE NORTHERN PLAINS. AS THE FRONT AND MCS MOVE
EAST...SEVERE WEATHER CHANCES ARE THE MAIN FORECAST CONCERNS.
FOR THE REST OF THIS AFTERNOON...HEIGHT FALLS AHEAD OF THE MCS AND
SHORTWAVE FARTHER WEST MAY HELP TO REDUCE THE CAP OVER NORTHEAST
WISCONSIN. IF THE MCS STARTS A MORE NE TRACK DUE TO BACKING WIND
FIELDS ALOFT...ASCENT WILL SUPPORT THUNDERSTORM DEVELOPMENT OVER
PARTS OF CENTRAL AND EAST-CENTRAL WISCONSIN OVER THE NEXT FEW
HOURS. BUT ITS STILL NOT CLEAR IF THIS NE TRACK WILL OCCUR OR
THUNDERSTORMS COULD FORM BEFORE LIGHT RAIN ON THE NORTHERN EDGE OF
THE MCS ARRIVES. BEST CHANCES FOR THUNDERSTORM DEVELOPMENT WOULD BE
SOUTH OF A LINE FROM WAUTOMA TO GREEN BAY TO ALGOMA. ANY
THUNDERSTORMS WOULD BRING THE THREAT OF LARGE HAIL AND DAMAGING
WINDS. BUT ITS STARTING TO LOOK LIKE THE SEVERE THREAT WILL BE
CONFINED TO SOUTHERN WISCONSIN AND POINTS SOUTH. WILL HAVE TO KEEP
A MENTION OF SEVERE WEATHER...BUT CONFIDENCE HAS LOWERED TO THE DAY.
TONIGHT...FOLLOWING THE LEAD OF THE GFS AND HRRR...HEIGHT FALLS OVER
THE NORTHERN PLAINS SHOULD PROMOTE THE MCS OVER SOUTHERN MINNESOTA
AND IOWA TRACKING ENE ACROSS NORTHERN ILLINOIS AND SOUTHERN
WISCONSIN THIS EVENING. IF LIGHT RAIN DOES NOT EXTEND INTO AREAS
FROM WAUTOMA TO GREEN BAY TO ALGOMA THIS AFTERNOON...HEIGHT FALLS
AHEAD OF THE MCS COULD BE ENOUGH TO WEAKEN THE CAP LATE THIS
AFTERNOON INTO EARLY THIS EVENING TO PRODUCE SEVERE WEATHER IN THIS
CORRIDOR. UNCERTAINTY REMAINS HIGH THAT THIS WILL OCCUR AS
INSTABILITY IS CONSIDERABLY HIGHER OVER SOUTHERN PARTS OF THE
STATE...AND THE STRONGEST CONVECTION USUALLY FOLLOWS THE HIGHER
INSTABILITY. DUE TO THE STRONG WIND FIELDS ALOFT (45-55KTS OF 0-6KM
BULK SHEAR)...WILL HAVE TO KEEP THE POTENTIAL FOR SEVERE WEATHER IN
THE FORECAST UNTIL LATE EVENING...THOUGH FEELING IS THAT MOST OF THE
SEVERE WEATHER WILL REMAIN OVER SOUTHERN WISCONSIN. ISOLATED
COVERAGE REMAINS POSSIBLE OVER FAR NE WISCONSIN ASSUMING THE LIGHT
RAIN DOES NOT HOLD TOGETHER TO MAKE IT INTO THIS AREA. THE MAIN
THREATS WITH ANY CONVECTION WILL BE LARGE HAIL AND DAMAGING
WINDS...ALONG WITH THE POTENTIAL FOR HEAVY RAIN THOUGH THIS SHOULD
BE CONFINE TO THE WAUTOMA TO ALGOMA AREAS. ONCE THE PRECIP EXITS NE
WISCONSIN BY LATE IN THE EVENING...DRY SLOTTING SHOULD BRING
CLEARING SKIES FOR A SEVERAL HOUR PERIOD. THEN LOW STRATUS WILL
APPROACH N-C WISCONSIN LATE TONIGHT AS COLDER AIR FILTERS IN FROM
THE NORTHWEST. LOWS IN THE UPPER 50S TO MIDDLE 60S.
TUESDAY...UPPER TROUGHING WILL MOVE INTO THE WESTERN GREAT LAKES
WHICH WILL PROMOTE LOW LEVEL MOISTURE SURGING SOUTHEAST ACROSS THE
REGION. WITH DAYTIME INSTABILITY...CYCLONIC FLOW WILL SUPPORT
SHOWER DEVELOPMENT WHICH SHOULD HAVE GREATER COVERAGE OVER THE
HIGHER ELEVATION AREAS OF CENTRAL AND NORTH-CENTRAL WISCONSIN. HAVE
INCREASED PRECIP CHANCES INTO THE LIKELY RANGE DURING THE
AFTERNOON. HIGHS RANGING FROM THE UPPER 60S NORTH TO THE MIDDLE 70S
SOUTH.
.LONG TERM...TUESDAY NIGHT THROUGH MONDAY
ISSUED AT 330 PM CDT MON JUN 30 2014
MAIN FOCUS ON SHORT-TERM SEVERE/HEAVY RAINFALL THREAT THIS AFTERNOON
AND EVENING...SO WILL BE BRIEF WITH EXTENDED FCST DISCUSSION. MAIN
CONCERNS ARE LOW-END PCPN THREATS...AND A RETURN TO COOLER THAN
NORMAL TEMPS FOR A FEW DAYS.
AN UPPER LEVEL TROF AND CYCLONIC NW FLOW AT THE SFC WILL COMBINE
TO PRODUCE SCT SHOWERS OVER THE FORECAST AREA INTO MIDWEEK. CAA
AND CLOUD COVER WILL RESULT IN THE COOLEST DAY OF THE WEEK ON
WEDNESDAY...WITH HIGHS IN THE MID 60S TO LOWER 70S.
CANADIAN HIGH PRESSURE WILL RESIDE OVER THE WESTERN GREAT LAKES
REGION ON THURSDAY AND FRIDAY (4TH OF JULY)...BRINGING ABUNDANT
SUNSHINE...LOW HUMIDITY AND PLEASANT TEMPS IN THE LOWER TO MIDDLE
70S. THE WEATHER SHOULD BE PERFECT FOR 4TH OF JULY FIREWORKS
DISPLAYS.
THE SFC HIGH IS EXPECTED TO GRADUALLY SHIFT EAST DURING THE
WEEKEND...WITH RETURN FLOW ALLOWING A SMALL CHANCE OF SHOWERS
AND THUNDERSTORMS TO RETURN TO THE REGION. MOST MEDIUM-RANGE
MODELS SUGGEST THAT THE MAIN BRUNT OF THE PCPN WILL REMAIN
FOCUSED NEAR A WARM FRONT OVER IOWA AND NORTHERN IL OVER
THE WEEKEND...SO 20-30 POPS SHOULD COVER THE SITUATION.
TEMPERATURES WILL RETURN TO NORMAL LEVELS FOR EARLY JULY.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1159 AM CDT MON JUN 30 2014
SCT TO BKN MVFR CIGS WILL ENCOMPASS MUCH OF THE REGION
IN A HUMID AIRMASS EXCLUDING AREAS OVER FAR NORTH-CENTRAL WISCONSIN
WHERE DRIER AIR IS PRESENT. FOCUS OVER THE NEXT 12 HOURS IS THE
SHOWER AND THUNDERSTORM TIMING. LARGE CLUSTER OF SHOWERS AND STORMS
OVER SOUTHERN MINNESOTA AND IOWA WILL TRANSLATE EAST THIS AFTERNOON
AND ARE EXPECTED TO MOVE INTO CENTRAL WISCONSIN SHORTLY AFTER 18Z
AND EAST-CENTRAL WISCONSIN AFTER 20Z OR 21Z. ISOLATED STORMS ARE
EXPECTED TO FIRE NORTH OF THIS TRACK AND COULD BECOME STRONG TO
SEVERE. A BETTER CHANCE OF SEVERE STORMS WILL OCCUR FROM WAUTOMA TO
ALGOMA BETWEEN 21 AND 03Z AND LARGE HAIL/DAMAGING WINDS WILL BE THE
MAIN THREATS. STORMS WILL EXIT THE REGION BY MID TO LATE EVENING AS
COOLER AND DRIER AIR MOVES INTO THE STATE. A LARGE AREA OF STRATUS
WITHIN THIS COOLER AIRMASS IS EXPECTED TO ARRIVE TUESDAY MORNING AND
WILL LIKELY BRING SHOWER ACTIVITY TO MUCH OF THE REGION BY MIDDAY.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
BEACH HAZARDS STATEMENT UNTIL 9 PM CDT THIS EVENING FOR WIZ022.
&&
$$
SHORT TERM.....MPC
LONG TERM......KIECKBUSCH
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1217 PM CDT MON JUN 30 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 420 AM CDT MON JUN 30 2014
AT 4 AM...THE MESOSCALE CONVECTIVE COMPLEX...WHICH BROUGHT THE
HEAVY RAIN TO NORTHEAST IOWA AND SOUTHWEST WISCONSIN AND POSSIBLE
TORNADO NEAR FENNIMORE WISCONSIN...EXTENDED FROM SOUTHERN LAKE
MICHIGAN TO WEST-CENTRAL ILLINOIS. STRONG 850 MB MOISTURE
TRANSPORT AHEAD OF AN 850 MB LOW ACROSS CENTRAL NEBRASKA IS
GENERATING CLUSTERS OF THUNDERSTORMS ACROSS EASTERN NEBRASKA AND
AND NORTHWEST IOWA. SOME ADDITIONAL THUNDERSTORMS ARE STARTING TO
DEVELOP ALONG ALONG A 900 TO 700 MB FRONTOGENETIC BAND ACROSS
SOUTHERN SOUTH DAKOTA. THIS IS IN RESPONSE TO A STRONG SHORTWAVE
TROUGH MOVING THROUGH EASTERN MONTANA AND WYOMING.
FOR THIS MORNING...EXPECT ROUNDS OF SHOWERS AND THUNDERSTORMS TO
DEVELOP ALONG A 900 TO 700 MB BAND OF FRONTOGENESIS ALONG THE
MINNESOTA AND IOWA BORDER. THIS IS STRENGTHENING WILL LIKELY KEEP
THE PRECIPITATION GOING DESPITE THE WEAKENING THAT IS TAKING
PLACE IN THE 925 AND 850 MB MOISTURE TRANSPORT. DEEP MOISTURE
GRADUALLY POOLS ALONG THIS BOUNDARY DURING THE MORNING. ALONG AND
SOUTH OF INTERSTATE 90...WARM CLOUD LAYER DEPTHS CLIMB FROM 3 TO
3.5 KM AT 30.12Z TO AROUND 4 KM AT 30.18Z. DURING THIS SAME TIME
PERIOD...PRECIPITABLE WATER VALUES CLIMB FROM AROUND 1.5 INCHES TO
2.0 INCHES IN THIS SAME AREA. AS A RESULT...THE SHOWERS AND
THUNDERSTORMS WILL BECOME VERY EFFICIENT RAIN PRODUCERS.
IN ADDITION...MEAN LAYER CAPES WILL REMAIN FROM 1500 TO
3500 J/KG. WHILE TYPICALLY THIS INSTABILITY WOULD WANE FROM THE
CONVECTION... SOUTHERLY WINDS WILL CONTINUE TO ADVECT THIS
INSTABILITY FROM AREAS THAT ARE CAPPED TO OUR SOUTH. IN
ADDITION...THE 0-6 KM SHEAR WILL BE FAVORABLE FOR THE DEVELOPMENT
OF ELEVATED SUPERCELLS. WITH A MAJORITY OF THIS SHEAR LOCATED
BELOW 3 KM...THERE WILL BE THE POTENTIAL FOR THESE SUPERCELLS TO
EVOLVED INTO LINES.
FOR THIS AFTERNOON...BOTH THE DETERMINISTIC AND MESO MODELS
SUGGEST THAT CYCLOGENESIS WILL DEVELOP ACROSS NORTHEAST IOWA AND
SOUTHWEST WISCONSIN THIS AFTERNOON. THIS IS RESPONSE TO THE 850 MB
LOW AND STRONG SHORT WAVE TROUGH COMING TOGETHER ACROSS THE AREA.
DUE TO CONVECTIVE FEEDBACK...BOTH THE GFS AND NAM ARE LIKELY TOO
STRONG WITH THEIR CYCLOGENESIS AND THIS GREATLY AFFECTS THEIR WIND
FIELDS. AS RESULT...LOOKED MORE AT THE WIND FIELDS IN THE MESO
MODELS. EVEN THESE MODELS...SHOW A RAPID STRENGTHENING IN THE 925
AND 850 MB MOISTURE TRANSPORT INTO THE REGION. THIS CAUSES THE
PRECIPITABLE WATER VALUES TO CLIMB TO AROUND 2.25 INCHES AND WARM
CLOUD DEPTHS TO INCREASE INTO THE 4 TO 4.5 INCH RANGE. WITH UPWARD
FORCING BEING ENHANCED FURTHER AS THE AREA ENTERS THE RIGHT
ENTRANCE REGION OF A 250 MB...EXPECT THE THREAT FOR HEAVY RAIN TO
CONTINUE.
AS WITH THIS MORNING...THE 0-6 KM SHEAR WILL REMAIN IN THE EXCESS
OF 45 KNOTS THIS AFTERNOON. IN ADDITION THE COMBINATION OF THE
STRONG CAP TO OUR SOUTH AND SOUTHERLY WINDS CONTINUING TO BRING
THIS 2500 TO 3500 J/KG ML CAPES INTO THE AREA WILL PROVIDE AMPLE
INSTABILITY TO KEEP THE THREAT FOR SUPERCELLS GOING DESPITE THE
PERSISTENT CONVECTION ACROSS THE AREA. WITH THE INCREASING WINDS
FIELDS DUE TO THE CYCLOGENESIS...THE 0-1 KM HELICITY AND BULK
SHEAR ALONG WITH LCL HEIGHTS WILL BECOME FAVORABLE FOR THE
POTENTIAL OF TORNADOES ACROSS THE EASTERN PORTIONS OF NORTHEAST
IOWA AND IN SOUTHWEST WISCONSIN DURING THE MID AND LATTER PARTS OF
THE AFTERNOON. THE DUBUQUE RAP HODOGRAPH FOR 29.22Z IS VERY
IMPRESSIVE.
FOR THIS EVENING...THE SEVERE WEATHER AND HEAVY RAIN THREAT WILL
COME QUICKLY TO AN END AS THE SHORT WAVE TROUGH MOVES QUICKLY
THROUGH THE REGION.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 420 AM CDT MON JUN 30 2014
ON TUESDAY...ANOTHER SHORT WAVE TROUGH WILL MOVE THROUGH THE AREA.
UNLIKE TODAY...THERE WILL BE MUCH LESS INSTABILITY /500 TO
1000 J/KG SURFACE CAPES/ AND LESS 0-6 KM SHEAR LESS THAN 35 KNOTS.
AS A RESULT...JUST EXPECTING SHOWERS AND A FEW SCATTERED
THUNDERSTORMS.
ON WEDNESDAY...ANOTHER SHORT WAVE TROUGH MOVES THROUGH THE AREA.
WITH ML CAPES GENERALLY LESS 500 J/KG...MOST OF THE DETERMINISTIC
MODELS HAVE THIS PERIOD DRY. THE LONE EXCEPTION IS THE ECMWF WHICH
GENERATES A FEW SHOWERS. SINCE IT IS SUMMER AND THE ECMWF
TYPICALLY DOES BETTER IN THIS TIME PERIOD...JUST KEPT A SLIGHT
CHANCE OF SHOWERS GOING.
FROM THE FOURTH OF JULY INTO THE UPCOMING WEEKEND...THE MODELS
CONTINUE TO STRUGGLE WITH THEIR TIMING AND LOCATION OF WAVES...SO
JUST STAYED WITH THE MODEL CONSENSUS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1217 PM CDT MON JUN 30 2014
A TROUGH OF LOW PRESSURE WILL SWING THROUGH THE AREA THIS
AFTERNOON FOR ANOTHER ROUND OF SHRA/TS. VFR CONDITIONS EXPECTED
THROUGH THE MAJORITY OF THIS SHRA/TS ACTIVITY AT KRST/KLSE...BUT
PROBABLY WILL SEE BRIEF BOUTS OF MVFR CONDITIONS. LOOK FOR ANY
SEVERE ACTIVITY TO REMAIN MAINLY SOUTH OF I-90 THROUGH THIS
AFTERNOON. SKIES EXPECTED TO SCATTER OUT THIS EVENING BRIEFLY
BEHIND THE TROUGH AND DEPARTING CONVECTION. MODELS ARE THEN INDICATING
A STRATOCUMULUS FIELD WITH BASES SLIPPING INTO HIGHER-END MVFR
CATEGORY AFTER 10Z AS COOLER CYCLONIC FLOW ALOFT OVERSPREADS THE
REGION. LOOKS LIKE SOME SHOWERS WILL START POPPING UP BY LATE
TUESDAY MORNING AS WELL ASSOCIATED WITH COLDER AIR ALOFT/STEEP LOW
LEVEL LAPSE RATES. VSBY EXPECTED TO REMAIN VFR BUT CLOUD CIGS
STRADDLING MVFR/VFR CONDITIONS.
&&
.HYDROLOGY...
ISSUED AT 420 AM CDT MON JUN 30 2014
WITH DEEP WARM CLOUD DEPTHS...PRECIPITABLE WATER VALUES OF 2 TO
2.25 INCHES...SATURATED SOILS...AND ALREADY HIGH RIVERS AND
STREAM ACROSS NORTHEAST IOWA AND SOUTHEAST MINNESOTA...ISSUED A
FLASH FLOOD WATCH TODAY FOR THE POTENTIAL OF 1 TO 3 INCHES OF
ADDITIONAL RAIN. THERE WILL LIKELY BE LOCALLY HIGHER AMOUNTS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...FLASH FLOOD WATCH UNTIL 7 PM CDT THIS EVENING FOR WIZ054-055-061.
MN...NONE.
IA...FLASH FLOOD WATCH UNTIL 7 PM CDT THIS EVENING FOR IAZ008>011-018-
019-029-030.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...DAS
HYDROLOGY...BOYNE