Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/02/13
AREA FORECAST DISCUSSION
NWS TUCSON AZ
930 AM MST FRI MAY 31 2013
.SYNOPSIS...HIGH PRESSURE ALOFT WILL BRING DRY CONDITIONS WITH WELL
ABOVE NORMAL TEMPERATURES THROUGH THE MIDDLE OF NEXT WEEK.
&&
.DISCUSSION...THE SHALLOW MOISTURE THAT WAS AROUND YESTERDAY MORNING
MADE A RETURN LAST NIGHT INTO THIS MORNING...WITH SURFACE DEWPOINTS
HIGHER THEN YESTERDAY. ALMOST MONSOON LIKE FROM TUCSON WEST. THIS
MOISTURE ALSO BROUGHT A HAZY SKY TO THE AREA THIS MORNING ALONG WITH
WARMER OVERNIGHT LOW TEMPERATURES.
THE MAIN FORECAST CHALLENGE OF THE DAY SURROUNDS THE THIRD ATTEMPT
THIS MONTH FOR HITTING 100 DEGREES AT THE TUCSON AIRPORT FOR THE
FIRST TIME IN 2013. 850-700 MB THICKNESS VALUES ON THE MORNING
SOUNDING WERE UP VERSUS YESTERDAY AND IF YOU ADD THAT INCREASE TO
YESTERDAY AFTERNOON 850-700 MB TKNS VALUE...99 IS PRETTY CERTAIN
WITH AN OUTSIDE CHANCE FOR 100. BASED ON 850-700 MB THICKNESS VALUES
FOR THIS AFTERNOON 12Z NAM/12Z GFS GOING 98 OR 99...00Z ECMWF/12Z
UKMET/12Z CANADIAN INDICATING 100. 14Z HRRR/15Z RAP GOING WITH 99.
HOW MUCH OF THIS SHALLOW MOISTURE MIXES OUT WILL ALSO BE A KEY
TODAY. OTHERWISE ACROSS SE AZ...HIGHS WILL BE 1-4 DEGREES ABOVE
NORMAL. MAY SEE SOME FLAT CU AROUND THIS AFTERNOON ESPECIALLY EAST
OF TUCSON AND UP IN THE WHITES.
&&
.AVIATION...SKC THRU SATURDAY MORNING OR 01/15Z. SURFACE WIND
THIS AFTERNOON AND EARLY THIS EVENING WLY/NWLY 10-18 KTS WITH GUSTS
OF 20-25 KTS... STRONGEST WIND EAST OF KTUS. OTHERWISE...SURFACE
WIND LESS THAN 10 KTS. AVIATION DISCUSSION NOT UPDATED FOR TAF
AMENDMENTS.
&&
.FIRE WEATHER...DRY CONDITIONS WITH WELL ABOVE NORMAL DAYTIME
TEMPERATURES WILL PREVAIL INTO THE MIDDLE OF NEXT WEEK. DAYTIME
MINIMUM RELATIVE HUMIDITIES WILL GENERALLY BE IN THE SINGLE DIGITS
TO LOWER TEENS WITH FAIR TO POOR OVERNIGHT RECOVERIES. NORMAL
DIURNAL WIND TRENDS WILL OCCUR...WITH OCCASIONAL GUSTS DURING THE
AFTERNOON HOURS DUE TO STRONG DAYTIME HEATING.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
845 PM EDT SAT JUN 1 2013
.UPDATE (TONIGHT AND SUNDAY)...
00Z WATER VAPOR AND H4 RAP ANALYSIS CONTINUE TO SHOW AN AMPLIFIED
UPPER PATTERN ACROSS THE CONUS THIS EVENING. SHARP TROUGHING IS NOW
EJECTING EASTWARD FROM THE CENTRAL PLAINS TOWARD THE GREAT
LAKES/APPALACHIANS. IN RESPONSE...LONGWAVE RIDGING IS BEGINNING TO
GIVE UP ITS HOLD ON THE MID-ATLANTIC AND NORTHEASTERN STATES. OUR
REGION REMAIN IN A WEAK OR ILL-DEFINED UPPER LEVEL PATTERN. WV
IMAGERY CONTINUES TO SHOW A SHARP MID/UPPER LEVEL MOISTURE
SEPARATING DRIER AIR ALOFT OVER THE NORTHERN FL PENINSULA FROM DEEP
MOISTURE OVER THE SOUTH.
AT THE SURFACE...SUBTROPICAL RIDGE AXIS IS LOCATED TO OUR NORTH OFF
THE GA/CAROLINA COASTLINE...BUT HAS WEAKENED ITS INFLUENCE ON THE
REGION OVER THE PAST 24 HOURS. THE WEAKER GRADIENT ALLOWED A
WELL-DEFINED SEA-BREEZE TO BECOME ESTABLISHED THIS AFTERNOON WHICH
COMBINED WITH WEAK EASTERLY SYNOPTIC FLOW TO FOCUS THE DIURNAL
CONVECTION TOWARD THE WEST COAST OF THE PENINSULA DURING THE
AFTERNOON/EVENING.
REST OF TONIGHT...THE COMBINATION OF THE LOSS OF DIURNAL HEATING AND
COLUMN OVERTURNING DUE TO ONGOING OR PAST CONVECTION SHOULD SLOWLY
ALLOW THE REMAIN SHOWERS/STORMS TO FADE INTO THE LATER EVENING
HOURS. LOCAL HI-RES CONVECTION MODELS SHOW MUCH OF THE ACTIVITY GONE
BY MIDNIGHT FOLLOWED BY A GENERALLY DRY REST OF THE OVERNIGHT.
PREVIOUS FORECAST HAD THIS TREND IN THE RAIN CHANCES AND SEE LITTLE
REASON FOR SIGNIFICANT CHANGES.
SUNDAY...
LOCAL GRADIENT ACROSS THE PENINSULA LOOKS TO SLACKEN EVEN FURTHER
FOR THE SECOND HALF OF THE WEEKEND. MORNING WILL START OUT
QUIET...WARM AND MUGGY WITH A MIX OF SUN AND CLOUDS. GOOD MODEL
AGREEMENT THAT WE WILL SEE WELL-DEFINED WEST AND EAST COAST
SEA-BREEZE DEVELOPMENT...WITH NEITHER BECOMING DOMINANT. LOCAL
HI-RES WRF-ARW MODELS ALL SHOW A SEA-BREEZE COLLISION OVER THE
INTERIOR PENINSULA LATE SUNDAY AFTERNOON. INITIAL SHOWER/STORM
DEVELOPMENT WILL BE NEAR THE COAST DURING THE EARLY AFTERNOON...BUT
THEN PUSH INLAND AND BECOME MORE ROBUST OVER PLACES LIKE
POLK/HIGHLANDS/DESOTO/HARDEE COUNTIES WHERE LOW LEVEL CONVERGENCE
WILL BE MAXIMIZED BY THE COLLIDING BOUNDARIES.
ALTHOUGH BEACHGOERS MAY SEE A BRIEF SHOWER OR STORM EARLY...IF THIS
SCENARIO DOES INDEED OCCUR...CONDITIONS ARE LIKELY TO CLEAR NEAR THE
BEACHES FOR MUCH OF THE AFTERNOON/EARLY EVENING AS THE SEA-BREEZE
MOVES INLAND AND TAKES THE STORMS WITH IT.
&&
.AVIATION...
TSRA/SHRA END AROUND 03Z. MAINLY MID LEVEL BKN DECK OVERNIGHT WITH
SOME LOWER CLOUDS BUT ANTICIPATE BKN MVFR ONLY AT LAL/PGD. SLIGHTLY
LIGHTER WINDS IN THE SOUTH MAY RESULT IN LIMITED BR AT PGD/FMY/RSW
LATER TONIGHT. DEEPER MOISTURE ADVECTING ACROSS THE AREA FROM THE
SOUTH SUN WILL SUPPORT LATE MORNING SHRA AND AFTERNOON TSRA.
&&
.MARINE...
HIGH PRESSURE WILL REMAIN THE DOMINANT WEATHER FEATURE THROUGH THE
WEEKEND. A DEVELOPING AREA OF LOW PRESSURE IN THE SOUTHWEST GULF OF
MEXICO WILL MOVE NORTHEAST EARLY NEXT WEEK...WITH INCREASING WINDS
AND SEAS. BY MONDAY NIGHT...MARINE CONDITIONS COULD DETERIORATE TO
SMALL CRAFT ADVISORY LEVELS...PARTICULARLY OVER THE SOUTHERN WATERS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 75 89 75 86 / 30 50 30 60
FMY 73 89 74 85 / 30 60 20 60
GIF 73 91 72 89 / 30 60 40 60
SRQ 73 87 74 86 / 30 40 20 60
BKV 71 90 71 88 / 30 40 30 50
SPG 76 88 76 86 / 30 40 20 60
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE...MROCZKA
AVIATION...RUDE
AREA FORECAST DISCUSSION
NWS MIAMI FL
1016 AM EDT FRI MAY 31 2013
.UPDATE...
NO CHANGES WERE REQUIRED TO THE CURRENT FORECAST. THE 12Z SOUNDING
INDICATED THAT TROPICAL MOISTURE CONTINUES ACROSS THE REGION WITH
A PWAT JUST OVER TWO INCHES WHICH IS ABOUT 20 PERCENT ABOVE THE NORMAL
PWAT FOR THIS DATE. THE FORECAST FOR THE REST OF TODAY IS IN LINE
WITH THE LATEST MESO-SCALE MODEL GUIDANCE INDICATING THAT THE MOST
ACTIVE PERIOD FOR SHOWERS/THUNDERSTORMS WILL BE THIS AFTERNOON
WITH MOST OF THE COVERAGE EXPECTED ACROSS THE WESTERN PORTIONS OF
THE PENINSULA AFTER 18Z THIS AFTERNOON. THE GUIDANCE ALSO CONTINUES
TO INDICATE THAT THE PRESSURE GRADIENT AND RESULTANT STRONG WINDS
ACROSS THE ATLANTIC WATERS WILL CONTINUE TO SLOWLY DECREASE AS
THE DAY PROGRESSES WITH THE SMALL CRAFT ADVISORY FOR THE ATLANTIC
WATERS AND BISCAYNE BAY EXPIRING AFTER 00Z THIS EVENING...WHICH IS
IN LINE WITH CURRENT OBSERVATION TRENDS.
60
&&
.PREV DISCUSSION... /ISSUED 658 AM EDT FRI MAY 31 2013/
AVIATION...
A BERMUDA CONTINUES TO CONTROL THE WEATHER PATTERN OVER SOUTH
FLORIDA FOR AT LEAST ANOTHER DAY OR TWO. THIS WILL KEEP EAST TO
SOUTHEASTERLY WINDS IN THE FORECAST THROUGH THE TAF PERIOD. IT
WILL ALSO KEEP SHOWERS IN THEM AS WELL. SOME MODELS ARE SUGGESTING
THAT THE PRECIPITATION WILL MOVE OFF TO THE WESTERN SIDE OF THE
STATE, AND BE ENHANCED AS IT REACHES THE GULF COAST. THUS, HAVE
TAKEN MENTION OF RAIN OUT FOR NOW AFTER 19Z, EXCEPT AT KAPF, WHERE
IT IS QUIET NOW AND ADDED RAIN AFTER 18Z. THERE IS ALSO A CHANCE
FOR THUNDERSTORMS THIS AFTERNOON ALONG THE GULF COAST. WITH ANY OF
THE HEAVIER SHOWERS, MVFR AND IFR WILL BE POSSIBLE FOR BRIEF
PERIOD OF TIME.
PREV DISCUSSION... /ISSUED 249 AM EDT FRI MAY 31 2013/
SHORT TERM (TODAY THROUGH SUNDAY)...
MODELS CONTINUE TO HAVE ISSUES WITH THE SURFACE PRESSURE PATTERNS
BUT ARE IN GOOD AGREEMENT WITH THE MID LEVELS. A WEAK PRESSURE
PATTERN ALOFT IS FORECAST TO CONTINUE WITH ABUNDANT DEEP LAYER
MOISTURE IN PLACE WITH PWAT VALUES HOVERING AROUND TWO INCHES. AT
THE SURFACE, THE GFS HAS TRENDED WITH THE ECMWF IN CONTINUING THE
HIGH PRESSURE OVER THE SOUTHEAST STATES BUT SHIFTING IT TO THE
EAST OVER THE WEEKEND AS A WEAK COLD FRONT MOVES INTO THE
SOUTHEAST STATES. THIS WILL RESULT IN RETAINING A STRONG SOUTHEAST
LOW LEVEL FLOW TODAY AND THEN DIMINISHING SATURDAY AND SUNDAY.
THE NAM SEEMS TO BE SUFFERING FROM SOME OF ITS MESOSCALE BIASING
AS IT DEVELOPS A INVERTED TROUGH ALONG THE WEST COAST OF THE
PENINSULA VEERING THE LOW LEVEL FLOW TO THE SOUTH ACROSS OUR
REGION. THE GFS AND ECMWF RETAIN THE THE SOUTHEAST FLOW AND THIS
SEEMS MORE REASONABLE. SO THE HIGH RISK OF RIP CURRENTS WILL
CONTINUE TODAY AND SATURDAY WITH A LESSER THREAT ON SUNDAY BUT
LIKELY MAINTAINING A MODERATE RISK.
THE MAV AND MET GUIDANCE IS NEARLY IN PERFECT AGREEMENT WITH
LIKELY POPS TODAY AND SUNDAY WITH A LESSER CHANCE ON SUNDAY.
HOWEVER, RADAR SIGNATURES ARE NOT TERRIBLY IMPRESSIVE CURRENTLY
AND THE SHORT TERM HIGH RESOLUTION MODELS ARE NOT IN AGREEMENT ON
THE EVOLUTION TOWARDS SUNRISE INTO THE EARLY MORNING. BOTH THE
HRRR AND THE WRF HAVE INITIALIZED WELL IN DEPICTING FAST MOVING
SHOWERS OVER THE ATLANTIC AND MOVING ONSHORE ALONG THE SOUTHEAST
COAST. THE WRF THEN FLARES UP CONVECTION ALONG THE NORTHERN
BROWARD AND PALM BEACH COASTS AROUND 09Z AND DEVELOPS HEAVY
SHOWERS OVER MUCH OF EASTERN PALM BEACH COUNTY. THE HRRR ON THE
OTHER HAND KEEPS THE SHOWERS MINIMAL AND THEN CLEARS OUT THE EAST
COAST DURING THE MORNING WITH ADDITIONAL ACTIVITY DEVELOPING OVER
THE WESTERN HALF IN THE LATE MORNING AS THEY MOVE TOWARDS COASTAL
COLLIER COUNTY. GIVEN THE STATE OF THE CURRENT ATMOSPHERE AND THE
HIGHER RELIABILITY OF THE HRRR, WILL UNDERCUT THE POPS BY AROUND
ONE CATEGORY FROM GUIDANCE.
LONG TERM (SUNDAY NIGHT THROUGH THURSDAY)...
THE GFS AND ECMWF ARE BOTH IN GOOD AGREEMENT IN THE EXTENDED
PERIOD IN MAINTAINING A MOIST AND UNSTABLE ENVIRONMENT OVER SOUTH
FLORIDA WITH WEAK PRESSURE PATTERNS BOTH AT THE SURFACE AND ALOFT.
THIS WILL RESULT IN A MORE TYPICAL SEA BREEZE DRIVEN CONVECTION
PATTERN DURING THE AFTERNOONS AND EVENINGS WITH SLOW STORM MOTION.
AVIATION...
ATLANTIC SHOWERS WILL CONTINUE MOVE ONSHORE THROUGH THE MORNING
ALONG THE EAST COAST AND THEN TRANSITION TOWARDS KAPF DURING THE
AFTERNOON. THERE COULD BE A FEW THUNDERSTORMS ALONG THE WEST COAST
THIS AFTERNOON BUT COVERAGE DOES NOT WARRANT MENTION IN THE TAF AT
THIS TIME. EAST WIND CONTINUES TO BE MODERATE THIS MORNING BUT THE
GRADIENT WILL BEGIN TO RELAX THIS AFTERNOON BUT STILL EXPECTED TO
BE STRONG ENOUGH TO INHIBIT SEA BREEZE DEVELOPMENT ALONG THE
COLLIER COUNTY COAST.
MARINE...
MARINE CONDITIONS WILL CONTINUE TO BE ROUGH ESPECIALLY ALONG THE
ATLANTIC SIDE WITH SCA IN EFFECT. THE SCA WILL BE EXTENDED INTO
THIS AFTERNOON WITH THESE CONDITIONS SLOWLY BEGINNING TO SUBSIDE
OVER THE WEEKEND AS THE HIGH PRESSURE SHIFTS TO THE EAST AND THE
GRADIENT WEAKENS.
FIRE WEATHER...
AMPLE TROPICAL MOISTURE SO NO PROBLEMS OR CONCERNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 83 74 85 73 / 50 30 60 30
FORT LAUDERDALE 87 77 88 75 / 50 40 60 40
MIAMI 86 75 89 76 / 50 40 60 40
NAPLES 86 75 84 75 / 60 30 60 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...RIP CURRENT RISK UNTIL 6 PM EDT THIS EVENING FOR COASTAL BROWARD-
COASTAL MIAMI DADE-COASTAL PALM BEACH.
AM...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR BISCAYNE
BAY-COASTAL WATERS FROM DEERFIELD BEACH TO OCEAN REEF, FL
OUT 20 NM-COASTAL WATERS FROM JUPITER INLET TO DEERFIELD
BEACH, FL OUT 20 NM-WATERS FROM DEERFIELD BEACH TO OCEAN
REEF, FL EXTENDING FROM 20 NM TO THE TERRITORIAL WATERS OF
THE BAHAMAS-WATERS FROM JUPITER INLET TO DEERFIELD BEACH,
FL EXTENDING FROM 20 NM TO 60 NM.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...60/BD
AVIATION/RADAR...17/ERA
AREA FORECAST DISCUSSION
NWS MIAMI FL
658 AM EDT FRI MAY 31 2013
.AVIATION...
A BERMUDA CONTINUES TO CONTROL THE WEATHER PATTERN OVER SOUTH
FLORIDA FOR AT LEAST ANOTHER DAY OR TWO. THIS WILL KEEP EAST TO
SOUTHEASTERLY WINDS IN THE FORECAST THROUGH THE TAF PERIOD. IT
WILL ALSO KEEP SHOWERS IN THEM AS WELL. SOME MODELS ARE SUGGESTING
THAT THE PRECIPITATION WILL MOVE OFF TO THE WESTERN SIDE OF THE
STATE, AND BE ENHANCED AS IT REACHES THE GULF COAST. THUS, HAVE
TAKEN MENTION OF RAIN OUT FOR NOW AFTER 19Z, EXCEPT AT KAPF, WHERE
IT IS QUIET NOW AND ADDED RAIN AFTER 18Z. THERE IS ALSO A CHANCE
FOR THUNDERSTORMS THIS AFTERNOON ALONG THE GULF COAST. WITH ANY OF
THE HEAVIER SHOWERS, MVFR AND IFR WILL BE POSSIBLE FOR BRIEF
PERIOD OF TIME.
&&
.PREV DISCUSSION... /ISSUED 249 AM EDT FRI MAY 31 2013/
SHORT TERM (TODAY THROUGH SUNDAY)...
MODELS CONTINUE TO HAVE ISSUES WITH THE SURFACE PRESSURE PATTERNS
BUT ARE IN GOOD AGREEMENT WITH THE MID LEVELS. A WEAK PRESSURE
PATTERN ALOFT IS FORECAST TO CONTINUE WITH ABUNDANT DEEP LAYER
MOISTURE IN PLACE WITH PWAT VALUES HOVERING AROUND TWO INCHES. AT
THE SURFACE, THE GFS HAS TRENDED WITH THE ECMWF IN CONTINUING THE
HIGH PRESSURE OVER THE SOUTHEAST STATES BUT SHIFTING IT TO THE
EAST OVER THE WEEKEND AS A WEAK COLD FRONT MOVES INTO THE
SOUTHEAST STATES. THIS WILL RESULT IN RETAINING A STRONG SOUTHEAST
LOW LEVEL FLOW TODAY AND THEN DIMINISHING SATURDAY AND SUNDAY.
THE NAM SEEMS TO BE SUFFERING FROM SOME OF ITS MESOSCALE BIASING
AS IT DEVELOPS A INVERTED TROUGH ALONG THE WEST COAST OF THE
PENINSULA VEERING THE LOW LEVEL FLOW TO THE SOUTH ACROSS OUR
REGION. THE GFS AND ECMWF RETAIN THE THE SOUTHEAST FLOW AND THIS
SEEMS MORE REASONABLE. SO THE HIGH RISK OF RIP CURRENTS WILL
CONTINUE TODAY AND SATURDAY WITH A LESSER THREAT ON SUNDAY BUT
LIKELY MAINTAINING A MODERATE RISK.
THE MAV AND MET GUIDANCE IS NEARLY IN PERFECT AGREEMENT WITH
LIKELY POPS TODAY AND SUNDAY WITH A LESSER CHANCE ON SUNDAY.
HOWEVER, RADAR SIGNATURES ARE NOT TERRIBLY IMPRESSIVE CURRENTLY
AND THE SHORT TERM HIGH RESOLUTION MODELS ARE NOT IN AGREEMENT ON
THE EVOLUTION TOWARDS SUNRISE INTO THE EARLY MORNING. BOTH THE
HRRR AND THE WRF HAVE INITIALIZED WELL IN DEPICTING FAST MOVING
SHOWERS OVER THE ATLANTIC AND MOVING ONSHORE ALONG THE SOUTHEAST
COAST. THE WRF THEN FLARES UP CONVECTION ALONG THE NORTHERN
BROWARD AND PALM BEACH COASTS AROUND 09Z AND DEVELOPS HEAVY
SHOWERS OVER MUCH OF EASTERN PALM BEACH COUNTY. THE HRRR ON THE
OTHER HAND KEEPS THE SHOWERS MINIMAL AND THEN CLEARS OUT THE EAST
COAST DURING THE MORNING WITH ADDITIONAL ACTIVITY DEVELOPING OVER
THE WESTERN HALF IN THE LATE MORNING AS THEY MOVE TOWARDS COASTAL
COLLIER COUNTY. GIVEN THE STATE OF THE CURRENT ATMOSPHERE AND THE
HIGHER RELIABILITY OF THE HRRR, WILL UNDERCUT THE POPS BY AROUND
ONE CATEGORY FROM GUIDANCE.
LONG TERM (SUNDAY NIGHT THROUGH THURSDAY)...
THE GFS AND ECMWF ARE BOTH IN GOOD AGREEMENT IN THE EXTENDED
PERIOD IN MAINTAINING A MOIST AND UNSTABLE ENVIRONMENT OVER SOUTH
FLORIDA WITH WEAK PRESSURE PATTERNS BOTH AT THE SURFACE AND ALOFT.
THIS WILL RESULT IN A MORE TYPICAL SEA BREEZE DRIVEN CONVECTION
PATTERN DURING THE AFTERNOONS AND EVENINGS WITH SLOW STORM MOTION.
AVIATION...
ATLANTIC SHOWERS WILL CONTINUE MOVE ONSHORE THROUGH THE MORNING
ALONG THE EAST COAST AND THEN TRANSITION TOWARDS KAPF DURING THE
AFTERNOON. THERE COULD BE A FEW THUNDERSTORMS ALONG THE WEST COAST
THIS AFTERNOON BUT COVERAGE DOES NOT WARRANT MENTION IN THE TAF AT
THIS TIME. EAST WIND CONTINUES TO BE MODERATE THIS MORNING BUT THE
GRADIENT WILL BEGIN TO RELAX THIS AFTERNOON BUT STILL EXPECTED TO
BE STRONG ENOUGH TO INHIBIT SEA BREEZE DEVELOPMENT ALONG THE
COLLIER COUNTY COAST.
MARINE...
MARINE CONDITIONS WILL CONTINUE TO BE ROUGH ESPECIALLY ALONG THE
ATLANTIC SIDE WITH SCA IN EFFECT. THE SCA WILL BE EXTENDED INTO
THIS AFTERNOON WITH THESE CONDITIONS SLOWLY BEGINNING TO SUBSIDE
OVER THE WEEKEND AS THE HIGH PRESSURE SHIFTS TO THE EAST AND THE
GRADIENT WEAKENS.
FIRE WEATHER...
AMPLE TROPICAL MOISTURE SO NO PROBLEMS OR CONCERNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 83 74 85 73 / 50 30 60 30
FORT LAUDERDALE 87 77 88 75 / 50 40 60 40
MIAMI 86 75 89 76 / 50 40 60 40
NAPLES 86 75 84 75 / 60 30 60 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...RIP CURRENT RISK UNTIL 6 PM EDT THIS EVENING FOR COASTAL BROWARD-
COASTAL MIAMI DADE-COASTAL PALM BEACH.
AM...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR BISCAYNE
BAY-COASTAL WATERS FROM DEERFIELD BEACH TO OCEAN REEF, FL
OUT 20 NM-COASTAL WATERS FROM JUPITER INLET TO DEERFIELD
BEACH, FL OUT 20 NM-WATERS FROM DEERFIELD BEACH TO OCEAN
REEF, FL EXTENDING FROM 20 NM TO THE TERRITORIAL WATERS OF
THE BAHAMAS-WATERS FROM JUPITER INLET TO DEERFIELD BEACH,
FL EXTENDING FROM 20 NM TO 60 NM.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...30/KOB
AVIATION/RADAR...13/SI
AREA FORECAST DISCUSSION
NWS MIAMI FL
249 AM EDT FRI MAY 31 2013
.SHORT TERM (TODAY THROUGH SUNDAY)...
MODELS CONTINUE TO HAVE ISSUES WITH THE SURFACE PRESSURE PATTERNS
BUT ARE IN GOOD AGREEMENT WITH THE MID LEVELS. A WEAK PRESSURE
PATTERN ALOFT IS FORECAST TO CONTINUE WITH ABUNDANT DEEP LAYER
MOISTURE IN PLACE WITH PWAT VALUES HOVERING AROUND TWO INCHES. AT
THE SURFACE, THE GFS HAS TRENDED WITH THE ECMWF IN CONTINUING THE
HIGH PRESSURE OVER THE SOUTHEAST STATES BUT SHIFTING IT TO THE
EAST OVER THE WEEKEND AS A WEAK COLD FRONT MOVES INTO THE
SOUTHEAST STATES. THIS WILL RESULT IN RETAINING A STRONG SOUTHEAST
LOW LEVEL FLOW TODAY AND THEN DIMINISHING SATURDAY AND SUNDAY.
THE NAM SEEMS TO BE SUFFERING FROM SOME OF ITS MESOSCALE BIASING
AS IT DEVELOPS A INVERTED TROUGH ALONG THE WEST COAST OF THE
PENINSULA VEERING THE LOW LEVEL FLOW TO THE SOUTH ACROSS OUR
REGION. THE GFS AND ECMWF RETAIN THE THE SOUTHEAST FLOW AND THIS
SEEMS MORE REASONABLE. SO THE HIGH RISK OF RIP CURRENTS WILL
CONTINUE TODAY AND SATURDAY WITH A LESSER THREAT ON SUNDAY BUT
LIKELY MAINTAINING A MODERATE RISK.
THE MAV AND MET GUIDANCE IS NEARLY IN PERFECT AGREEMENT WITH
LIKELY POPS TODAY AND SUNDAY WITH A LESSER CHANCE ON SUNDAY.
HOWEVER, RADAR SIGNATURES ARE NOT TERRIBLY IMPRESSIVE CURRENTLY
AND THE SHORT TERM HIGH RESOLUTION MODELS ARE NOT IN AGREEMENT ON
THE EVOLUTION TOWARDS SUNRISE INTO THE EARLY MORNING. BOTH THE
HRRR AND THE WRF HAVE INITIALIZED WELL IN DEPICTING FAST MOVING
SHOWERS OVER THE ATLANTIC AND MOVING ONSHORE ALONG THE SOUTHEAST
COAST. THE WRF THEN FLARES UP CONVECTION ALONG THE NORTHERN
BROWARD AND PALM BEACH COASTS AROUND 09Z AND DEVELOPS HEAVY
SHOWERS OVER MUCH OF EASTERN PALM BEACH COUNTY. THE HRRR ON THE
OTHER HAND KEEPS THE SHOWERS MINIMAL AND THEN CLEARS OUT THE EAST
COAST DURING THE MORNING WITH ADDITIONAL ACTIVITY DEVELOPING OVER
THE WESTERN HALF IN THE LATE MORNING AS THEY MOVE TOWARDS COASTAL
COLLIER COUNTY. GIVEN THE STATE OF THE CURRENT ATMOSPHERE AND THE
HIGHER RELIABILITY OF THE HRRR, WILL UNDERCUT THE POPS BY AROUND
ONE CATEGORY FROM GUIDANCE.
.LONG TERM (SUNDAY NIGHT THROUGH THURSDAY)...
THE GFS AND ECMWF ARE BOTH IN GOOD AGREEMENT IN THE EXTENDED
PERIOD IN MAINTAINING A MOIST AND UNSTABLE ENVIRONMENT OVER SOUTH
FLORIDA WITH WEAK PRESSURE PATTERNS BOTH AT THE SURFACE AND ALOFT.
THIS WILL RESULT IN A MORE TYPICAL SEA BREEZE DRIVEN CONVECTION
PATTERN DURING THE AFTERNOONS AND EVENINGS WITH SLOW STORM MOTION.
&&
.AVIATION...
ATLANTIC SHOWERS WILL CONTINUE MOVE ONSHORE THROUGH THE MORNING
ALONG THE EAST COAST AND THEN TRANSITION TOWARDS KAPF DURING THE
AFTERNOON. THERE COULD BE A FEW THUNDERSTORMS ALONG THE WEST COAST
THIS AFTERNOON BUT COVERAGE DOES NOT WARRANT MENTION IN THE TAF AT
THIS TIME. EAST WIND CONTINUES TO BE MODERATE THIS MORNING BUT THE
GRADIENT WILL BEGIN TO RELAX THIS AFTERNOON BUT STILL EXPECTED TO
BE STRONG ENOUGH TO INHIBIT SEA BREEZE DEVELOPMENT ALONG THE
COLLIER COUNTY COAST.
&&
.MARINE...
MARINE CONDITIONS WILL CONTINUE TO BE ROUGH ESPECIALLY ALONG THE
ATLANTIC SIDE WITH SCA IN EFFECT. THE SCA WILL BE EXTENDED INTO
THIS AFTERNOON WITH THESE CONDITIONS SLOWLY BEGINNING TO SUBSIDE
OVER THE WEEKEND AS THE HIGH PRESSURE SHIFTS TO THE EAST AND THE
GRADIENT WEAKENS.
&&
.FIRE WEATHER...
AMPLE TROPICAL MOISTURE SO NO PROBLEMS OR CONCERNS.
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 83 74 85 73 / 50 30 60 30
FORT LAUDERDALE 87 77 88 75 / 50 40 60 40
MIAMI 86 75 89 76 / 50 40 60 40
NAPLES 86 75 84 75 / 60 30 60 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...RIP CURRENT RISK THROUGH THIS AFTERNOON FOR COASTAL BROWARD-
COASTAL MIAMI DADE-COASTAL PALM BEACH.
AM...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR BISCAYNE
BAY-COASTAL WATERS FROM DEERFIELD BEACH TO OCEAN REEF, FL
OUT 20 NM-COASTAL WATERS FROM JUPITER INLET TO DEERFIELD
BEACH, FL OUT 20 NM-WATERS FROM DEERFIELD BEACH TO OCEAN
REEF, FL EXTENDING FROM 20 NM TO THE TERRITORIAL WATERS OF
THE BAHAMAS-WATERS FROM JUPITER INLET TO DEERFIELD BEACH,
FL EXTENDING FROM 20 NM TO 60 NM.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...30/KOB
AVIATION/RADAR...13/SI
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
950 PM CDT SAT JUN 1 2013
.DISCUSSION...
308 PM CDT
CONVETIVE TRENDS ARE THE MAIN FORECAST ISSUE THIS AFTERNOON. WILL
MAINTAIN FLASH FLOOD WATCH ACROSS SOUTHERN TIER OF COUNTIES
THROUGH ITS 00Z EXPIRATION.
SURFACE LOW PRESSURE WAS CENTERED OVER CENTRAL WI AT MID
AFTERNOON...WITH A COLD FRONT EXTENDING SOUTH THROUGH THE
MISSISSIPPI RIVER VALLEY THEN SOUTHWEST ACROSS MISSOURI. DESPITE
CONSIDERABLE CLOUD COVER NORTHWEST/WEST CENTRAL IL HAS DESTABILIZED
AS EXPECTED THIS AFTERNOON...WITH SCATTERED SHRA/TSRA DEVELOPING
ACROSS THE UIN-PIA-PNT AT 19Z. SPC RAP MESOANALYSIS GUIDANCE
INDICATES AN AXIS OF 500-1000 J/KG AND GENERALLY CONVERGENT LOW
LEVEL FLOW IN THAT REGION AHEAD OF THE SFC COLD FRONT...AND EXPECT
THAT THIS ACTIVITY WILL CONTINUE TO DEVELOP AND SPREAD NORTHEAST
OVER THE NEXT SEVERAL HOURS AIDED BY LARGE SCALE ASCENT ASSOCIATED
WITH SHORT WAVE TROUGH PROPAGATING ACROSS IA/MO PER GOES WATER VAPOR
IMAGERY. SUCCESSIVE RUNS OF THE HRRR HAVE MAINTAINED THE IDEA OF
SCATTERED STORMS/SMALL CLUSTERS LIFTING NORTHEAST THROUGH THE
CHICAGO METRO AREA THROUGH 23-01Z OR SO...BEFORE DIURNAL DECREASE IN
INSTABILITY WITH SUNSET RESULTS IN DECREASE IN COVERAGE THIS
EVENING. WHILE WIDESPREAD SEVERE WEATHER IS NOT ANTICIPATED...WITH
EFFECTIVE BULK SHEAR APPROACHING 30 KT AND DRIER AIR ALOFT...MAINLY
WEST WHERE A DCAPE AXIS OF 600-800 J/KG IS ANALYZED...WE COULD SEE A
FEW OF THE STRONGEST CELLS PRODUCE A LITTLE HAIL OR WIND DURING THE
REMAINDER OF THE AFTERNOON HOURS. ORGANIZED HEAVY RAINFALL SEEMS A
FAIRLY LOW PROBABILITY AT THIS POINT...THOUGH ANALYSIS/GUIDANCE
CONTINUES TO DEPICT PWATS NEAR 1.5 INCHES...BETTER LOW LEVEL
MOISTURE TRANSPORT AND SLIGHTLY SLOWER STORM PROPAGATION POTENTIAL
ACROSS THE SOUTHEASTERN COUNTIES OF THE CWA. SINCE A FLASH FLOOD
WATCH IS ALREADY IN PLACE THERE...AND WITH THESE AREAS HAVING
RECEIVED BETWEEN 2-3 INCHES OF RAINFALL IN YESTERDAY/LAST NIGHTS
MCS/S...ILL ALLOW THE WATCH TO RUN THROUGH ITS 00Z EXPIRATION.
COLD FRONT AND MID-LEVEL TROUGH AXIS PUSH ACROSS THE CWA THIS
EVENING...WITH DRIER AIR AND HEIGHT RISES SPREADING IN FROM THE WEST
OVERNIGHT. WEAKER SECONDARY FRONT TRAILS ACROSS THE AREA SUNDAY
MORNING HOWEVER...WITH MOST GUIDANCE RUNS INDICATING THE POTENTIAL
FOR A FEW SPOTTY SHOWERS MAINLY ACROSS EAST/SOUTHEAST PARTS OF THE
FORECAST AREA. BEYOND THAT...SURFACE HIGH PRESSURE WILL BUILD INTO
THE AREA LATER SUNDAY THROUGH MONDAY MAKING FOR A COUPLE OF DAYS OF
DRY AND COOLER WEATHER WITH AFTERNOON LAKE BREEZES. GUIDANCE
REASONABLE IN DEPICTING TEMPS IN THE MID/UPPER 60S SUNDAY...AND MID
60S TO LOWER 70S MONDAY...WITH LOWER 60S LIKELY ALONG THE LAKE
MICHIGAN SHORES. LOWS ARE EXPECTED TO BE IN THE 40S IN MANY AREAS
AWAY FROM THE CHICAGO METRO SPRAWL SUNDAY NIGHT AND AGAIN MONDAY
NIGHT.
UPPER LEVEL RIDGE AXIS DEVELOPS ACROSS THE REGION INTO TUESDAY...
WHILE CLOSED UPPER LOW CURRENTLY OFF THE BRITISH COLUMBIA COAST
MAKES ITS WAY INTO THE NORTHERN PLAINS. AS THIS OCCURS...THE SFC
HIGH OVER THE WESTERN LAKES WILL DRIFT TO THE EAST...WITH LOW LEVEL
FLOW MORE SOUTH-SOUTHEAST ACROSS THE PLAINS AND MISSISSIPPI VALLEY
BY MID-WEEK. THIS RETURN FLOW AND ASSOCIATED WARM/MOIST ADVECTION
WILL INITIALLY FOCUS ACROSS THE PLAINS AND INTO IA/MN
TUESDAY/TUESDAY NIGHT...BUT WILL SHIFT FARTHER EAST AND BRING
SHRA/TSRA CHANCES BACK TO OUR AREA LATER TUESDAY NIGHT AND
WEDNESDAY. SOME GUIDANCE HINTS AT A FEW SHRA/TSRA MOVING INTO OUR
NORTHWEST COUNTIES TUESDAY AFTERNOON...THOUGH THESE SHOULD BE
DECAYING AS THEY MOVE OUT OF THE BETTER FORCING/MOISTURE WEST OF THE
MISSISSIPPI AND HAVE MAINTAINED DRY FORECAST THROUGH THE DAY TUESDAY
WITH LOW CONFIDENCE OF ANY PRECIP OF SIGNIFICANCE MAKING IT THIS FAR
EAST. SHRA/TSRA CHANCES THEN INCREASE WEDNESDAY THROUGH THURSDAY AS
UPPER LOW AND INVERTED SURFACE TROUGH/COLD FRONT MOVE ACROSS THE
AREA. UPPER LOW FILLS AND OPENS UP DURING THIS TIME...WITH SOUTH
WARM/MOIST ADVECTION FLOW NOT TERRIBLY STRONG. SUSPECT THERE WILL BE
MANY DRY HOURS BETWEEN CLUSTERS OF SHRA/TSRA DURING THIS PERIOD.
TEMPS MODERATE BACK INTO THE LOW-MID 70S/NEAR NORMAL DURING THE
MID-WEEK PERIOD...THOUGH SOUTHEAST SYNOPTIC WINDS WILL KEEP WINDS
OFF THE LAKE PARTICULARLY ACROSS NORTHEAST IL.
SURFACE COLD FRONT SETTLES SLOWLY OFF TO THE SOUTH/SOUTHEAST OF THE
CWA THURSDAY NIGHT...THOUGH UPPER TROUGH AXIS LINGERS ACROSS THE
REGION INTO NEXT WEEKEND. HAVE HELD ONTO SOME SLIGHT CHANCE POPS
FRIDAY WITH THE TROUGH AXIS OVERHEAD AND THE ECMWF CONTINUING TO
SQUEEZE OUT QPF...THOUGH DRIER LOW LEVEL FLOW AROUND SFC HIGH
PRESSURE OVER THE NORTHERN LAKES SHOULD HELP MAINTAIN GENERALLY DRY
CONDITIONS BY FRIDAY NIGHT/SATURDAY. TEMPS DURING THE PERIOD
EXPECTED TO BE NEAR NORMAL...70S...THOUGH ONSHORE WINDS OFF THE BIG
POND WILL KEEP CONDITIONS COOLER NEAR THE LAKE.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 03Z...
* MVFR CIGS PROBABLE BEHIND FRONT LATE TONIGHT INTO SUN AM
* PERIOD OF IFR CIGS POSSIBLE SUNDAY MORNING
* WIND SHIFT TO NE SUNDAY AFTERNOON WITH LAKE BREEZE
IZZI
//DISCUSSION...UPDATED 00Z...
LAST VESTIAGES OF SHRA/TSRA WITH THIS SYSTEM ARE FINALLY MOVING
OUT OF THE AREA WITH GENERALLY VFR CONDITIONS AND WEST WINDS
EXPECTED REMAINDER OF THIS EVENING BEHIND THIS LAST BAND OF
WEATHER. SECONDARY COLD FRONT WILL BLAST THROUGH THE AREA LATE
TONIGHT WITH WIND SHIFT TO NNW AND SOME GUSTINESS EXPECTED.
ANTICIPATE LOWER END MVFR CIGS TO DEVELOP BEHIND THE FRONT WITH
SOME POTENTIAL FOR IFR CIGS...PARTICULARLY IF WINDS GO MORE
NORTHERLY AND WE GET A LAKE INFLUENCE INTO THE TERMINALS. CIGS
LIKELY TO SLOWLY LIFT DURING THE DAY SUNDAY WITH TRANSITION TO VFR
LIKELY SUNDAY AFTERNOON ALONG WITH A WIND SHIFT TO NE WITH LAKE
BREEZE. AT GYY...CLOSER PROXIMITY TO THE LAKE AND LIKELY FLOW OFF
THE LAKE SHOULD RESULT IN A PERIOD OF IFR OR EVEN LIFR BEHIND THE
FRONT EARLY SUNDAY MORNING.
IZZI
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* HIGH CONFIDENCE IN WIND TRENDS
* MEDIUM CONFIDENCE IN MVFR CIGS LATE TONIGHT/SUNDAY MORNING
* LOW CONFIDENCE IN IFR CIGS LATE TONIGHT/SUNDAY MORNING
* MEDIUM-HIGH CONFIDENCE ON WIND SHIFT TO NE SUNDAY AFTERNOON
IZZI
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY AND TUESDAY...VFR.
WEDNESDAY THROUGH FRIDAY...CHANCE OF SHRA/TSRA.
IZZI
&&
.MARINE...
218 PM CDT
MODERATE SOUTHERLY WINDS ARE OCCURRING AHEAD OF AN AREA OF LOW
PRESSURE AND ITS ATTENDANT COLD FRONT WHICH ARE EXPECTED TO PASS
OVER THE LAKE TONIGHT. A BRIEF LULL IN THE WINDS MAY OCCUR WITH THE
FRONTAL TROUGH THIS EVENING...BUT THEN WINDS ARE EXPECTED TO
SHIFT TO NORTHWESTERLY AND RAMP BACK UP INTO THE 20 TO 25 KT RANGE
FOR MUCH OF THE LAKE OVERNIGHT. WINDS SHOULD COME DOWN THROUGH
THE DAY SUNDAY...REMAINING RELATIVELY LIGHT ON MONDAY WITH LAKE
BREEZES DEVELOPING. ANOTHER AREA OF LOW PRESSURE BEGINS TO TAKE
SHAPE OVER THE PLAINS LATE MONDAY INTO TUESDAY WITH SOUTHEASTERLY
WINDS FRESHENING UP TO PERHAPS 15 TO 20 KT AT TIMES THROUGH
THURSDAY. THURSDAY NIGHT...THE LOW WEAKENS AS IT PASSES SOUTH OF
THE LAKE WITH WINDS TURNING NORTHERLY FRIDAY THROUGH THE WEEKEND.
BMD
&&
.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
NWS CHICAGO/ROMEOVILLE IL
652 PM CDT SAT JUN 1 2013
.DISCUSSION...
308 PM CDT
CONVETIVE TRENDS ARE THE MAIN FORECAST ISSUE THIS AFTERNOON. WILL
MAINTAIN FLASH FLOOD WATCH ACROSS SOUTHERN TIER OF COUNTIES
THROUGH ITS 00Z EXPIRATION.
SURFACE LOW PRESSURE WAS CENTERED OVER CENTRAL WI AT MID
AFTERNOON...WITH A COLD FRONT EXTENDING SOUTH THROUGH THE
MISSISSIPPI RIVER VALLEY THEN SOUTHWEST ACROSS MISSOURI. DESPITE
CONSIDERABLE CLOUD COVER NORTHWEST/WEST CENTRAL IL HAS DESTABILIZED
AS EXPECTED THIS AFTERNOON...WITH SCATTERED SHRA/TSRA DEVELOPING
ACROSS THE UIN-PIA-PNT AT 19Z. SPC RAP MESOANALYSIS GUIDANCE
INDICATES AN AXIS OF 500-1000 J/KG AND GENERALLY CONVERGENT LOW
LEVEL FLOW IN THAT REGION AHEAD OF THE SFC COLD FRONT...AND EXPECT
THAT THIS ACTIVITY WILL CONTINUE TO DEVELOP AND SPREAD NORTHEAST
OVER THE NEXT SEVERAL HOURS AIDED BY LARGE SCALE ASCENT ASSOCIATED
WITH SHORT WAVE TROUGH PROPAGATING ACROSS IA/MO PER GOES WATER VAPOR
IMAGERY. SUCCESSIVE RUNS OF THE HRRR HAVE MAINTAINED THE IDEA OF
SCATTERED STORMS/SMALL CLUSTERS LIFTING NORTHEAST THROUGH THE
CHICAGO METRO AREA THROUGH 23-01Z OR SO...BEFORE DIURNAL DECREASE IN
INSTABILITY WITH SUNSET RESULTS IN DECREASE IN COVERAGE THIS
EVENING. WHILE WIDESPREAD SEVERE WEATHER IS NOT ANTICIPATED...WITH
EFFECTIVE BULK SHEAR APPROACHING 30 KT AND DRIER AIR ALOFT...MAINLY
WEST WHERE A DCAPE AXIS OF 600-800 J/KG IS ANALYZED...WE COULD SEE A
FEW OF THE STRONGEST CELLS PRODUCE A LITTLE HAIL OR WIND DURING THE
REMAINDER OF THE AFTERNOON HOURS. ORGANIZED HEAVY RAINFALL SEEMS A
FAIRLY LOW PROBABILITY AT THIS POINT...THOUGH ANALYSIS/GUIDANCE
CONTINUES TO DEPICT PWATS NEAR 1.5 INCHES...BETTER LOW LEVEL
MOISTURE TRANSPORT AND SLIGHTLY SLOWER STORM PROPAGATION POTENTIAL
ACROSS THE SOUTHEASTERN COUNTIES OF THE CWA. SINCE A FLASH FLOOD
WATCH IS ALREADY IN PLACE THERE...AND WITH THESE AREAS HAVING
RECEIVED BETWEEN 2-3 INCHES OF RAINFALL IN YESTERDAY/LAST NIGHTS
MCS/S...ILL ALLOW THE WATCH TO RUN THROUGH ITS 00Z EXPIRATION.
COLD FRONT AND MID-LEVEL TROUGH AXIS PUSH ACROSS THE CWA THIS
EVENING...WITH DRIER AIR AND HEIGHT RISES SPREADING IN FROM THE WEST
OVERNIGHT. WEAKER SECONDARY FRONT TRAILS ACROSS THE AREA SUNDAY
MORNING HOWEVER...WITH MOST GUIDANCE RUNS INDICATING THE POTENTIAL
FOR A FEW SPOTTY SHOWERS MAINLY ACROSS EAST/SOUTHEAST PARTS OF THE
FORECAST AREA. BEYOND THAT...SURFACE HIGH PRESSURE WILL BUILD INTO
THE AREA LATER SUNDAY THROUGH MONDAY MAKING FOR A COUPLE OF DAYS OF
DRY AND COOLER WEATHER WITH AFTERNOON LAKE BREEZES. GUIDANCE
REASONABLE IN DEPICTING TEMPS IN THE MID/UPPER 60S SUNDAY...AND MID
60S TO LOWER 70S MONDAY...WITH LOWER 60S LIKELY ALONG THE LAKE
MICHIGAN SHORES. LOWS ARE EXPECTED TO BE IN THE 40S IN MANY AREAS
AWAY FROM THE CHICAGO METRO SPRAWL SUNDAY NIGHT AND AGAIN MONDAY
NIGHT.
UPPER LEVEL RIDGE AXIS DEVELOPS ACROSS THE REGION INTO TUESDAY...
WHILE CLOSED UPPER LOW CURRENTLY OFF THE BRITISH COLUMBIA COAST
MAKES ITS WAY INTO THE NORTHERN PLAINS. AS THIS OCCURS...THE SFC
HIGH OVER THE WESTERN LAKES WILL DRIFT TO THE EAST...WITH LOW LEVEL
FLOW MORE SOUTH-SOUTHEAST ACROSS THE PLAINS AND MISSISSIPPI VALLEY
BY MID-WEEK. THIS RETURN FLOW AND ASSOCIATED WARM/MOIST ADVECTION
WILL INITIALLY FOCUS ACROSS THE PLAINS AND INTO IA/MN
TUESDAY/TUESDAY NIGHT...BUT WILL SHIFT FARTHER EAST AND BRING
SHRA/TSRA CHANCES BACK TO OUR AREA LATER TUESDAY NIGHT AND
WEDNESDAY. SOME GUIDANCE HINTS AT A FEW SHRA/TSRA MOVING INTO OUR
NORTHWEST COUNTIES TUESDAY AFTERNOON...THOUGH THESE SHOULD BE
DECAYING AS THEY MOVE OUT OF THE BETTER FORCING/MOISTURE WEST OF THE
MISSISSIPPI AND HAVE MAINTAINED DRY FORECAST THROUGH THE DAY TUESDAY
WITH LOW CONFIDENCE OF ANY PRECIP OF SIGNIFICANCE MAKING IT THIS FAR
EAST. SHRA/TSRA CHANCES THEN INCREASE WEDNESDAY THROUGH THURSDAY AS
UPPER LOW AND INVERTED SURFACE TROUGH/COLD FRONT MOVE ACROSS THE
AREA. UPPER LOW FILLS AND OPENS UP DURING THIS TIME...WITH SOUTH
WARM/MOIST ADVECTION FLOW NOT TERRIBLY STRONG. SUSPECT THERE WILL BE
MANY DRY HOURS BETWEEN CLUSTERS OF SHRA/TSRA DURING THIS PERIOD.
TEMPS MODERATE BACK INTO THE LOW-MID 70S/NEAR NORMAL DURING THE
MID-WEEK PERIOD...THOUGH SOUTHEAST SYNOPTIC WINDS WILL KEEP WINDS
OFF THE LAKE PARTICULARLY ACROSS NORTHEAST IL.
SURFACE COLD FRONT SETTLES SLOWLY OFF TO THE SOUTH/SOUTHEAST OF THE
CWA THURSDAY NIGHT...THOUGH UPPER TROUGH AXIS LINGERS ACROSS THE
REGION INTO NEXT WEEKEND. HAVE HELD ONTO SOME SLIGHT CHANCE POPS
FRIDAY WITH THE TROUGH AXIS OVERHEAD AND THE ECMWF CONTINUING TO
SQUEEZE OUT QPF...THOUGH DRIER LOW LEVEL FLOW AROUND SFC HIGH
PRESSURE OVER THE NORTHERN LAKES SHOULD HELP MAINTAIN GENERALLY DRY
CONDITIONS BY FRIDAY NIGHT/SATURDAY. TEMPS DURING THE PERIOD
EXPECTED TO BE NEAR NORMAL...70S...THOUGH ONSHORE WINDS OFF THE BIG
POND WILL KEEP CONDITIONS COOLER NEAR THE LAKE.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* SHRA/ISOLD TSRA ENDING SHORTLY AFTER 00Z
* MVFR CIGS PROBABLE BEHIND FRONT LATE TONIGHT INTO SUN AM
* PERIOD OF IFR CIGS POSSIBLE SUNDAY MORNING
* WIND SHIFT TO NE SUNDAY AFTERNOON WITH LAKE BREEZE
IZZI
//DISCUSSION...UPDATED 00Z...
LAST VESTIAGES OF SHRA/TSRA WITH THIS SYSTEM ARE FINALLY MOVING
OUT OF THE AREA WITH GENERALLY VFR CONDITIONS AND WEST WINDS
EXPECTED REMAINDER OF THIS EVENING BEHIND THIS LAST BAND OF
WEATHER. SECONDARY COLD FRONT WILL BLAST THROUGH THE AREA LATE
TONIGHT WITH WIND SHIFT TO NNW AND SOME GUSTINESS EXPECTED.
ANTICIPATE LOWER END MVFR CIGS TO DEVELOP BEHIND THE FRONT WITH
SOME POTENTIAL FOR IFR CIGS...PARTICULARLY IF WINDS GO MORE
NORTHERLY AND WE GET A LAKE INFLUENCE INTO THE TERMINALS. CIGS
LIKELY TO SLOWLY LIFT DURING THE DAY SUNDAY WITH TRANSITION TO VFR
LIKELY SUNDAY AFTERNOON ALONG WITH A WIND SHIFT TO NE WITH LAKE
BREEZE. AT GYY...CLOSER PROXIMITY TO THE LAKE AND LIKELY FLOW OFF
THE LAKE SHOULD RESULT IN A PERIOD OF IFR OR EVEN LIFR BEHIND THE
FRONT EARLY SUNDAY MORNING.
IZZI
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* HIGH CONFIDENCE IN PRECIP TRENDS
* MEDIUM-HIGH CONFIDENCE IN WIND TRENDS
* MEDIUM CONFIDENCE IN MVFR CIGS LATE TONIGHT/SUNDAY MORNING
* LOW CONFIDENCE IN IFR CIGS LATE TONIGHT/SUNDAY MORNING
* MEDIUM-HIGH CONFIDENCE ON WIND SHIFT TO NE SUNDAY AFTERNOON
IZZI
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY AND TUESDAY...VFR.
WEDNESDAY THROUGH FRIDAY...CHANCE OF SHRA/TSRA.
IZZI
&&
.MARINE...
218 PM CDT
MODERATE SOUTHERLY WINDS ARE OCCURRING AHEAD OF AN AREA OF LOW
PRESSURE AND ITS ATTENDANT COLD FRONT WHICH ARE EXPECTED TO PASS
OVER THE LAKE TONIGHT. A BRIEF LULL IN THE WINDS MAY OCCUR WITH THE
FRONTAL TROUGH THIS EVENING...BUT THEN WINDS ARE EXPECTED TO
SHIFT TO NORTHWESTERLY AND RAMP BACK UP INTO THE 20 TO 25 KT RANGE
FOR MUCH OF THE LAKE OVERNIGHT. WINDS SHOULD COME DOWN THROUGH
THE DAY SUNDAY...REMAINING RELATIVELY LIGHT ON MONDAY WITH LAKE
BREEZES DEVELOPING. ANOTHER AREA OF LOW PRESSURE BEGINS TO TAKE
SHAPE OVER THE PLAINS LATE MONDAY INTO TUESDAY WITH SOUTHEASTERLY
WINDS FRESHENING UP TO PERHAPS 15 TO 20 KT AT TIMES THROUGH
THURSDAY. THURSDAY NIGHT...THE LOW WEAKENS AS IT PASSES SOUTH OF
THE LAKE WITH WINDS TURNING NORTHERLY FRIDAY THROUGH THE WEEKEND.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ032-ILZ039 UNTIL 7 PM SATURDAY.
FLASH FLOOD WATCH...ILZ033 UNTIL 10 PM SATURDAY.
IN...FLASH FLOOD WATCH...INZ010-INZ011-INZ019 UNTIL 10 PM SATURDAY.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565
UNTIL 9 PM SATURDAY.
&&
$$
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
533 PM CDT FRI MAY 31 2013
.DISCUSSION...
336 PM CDT
THOUGHTS FROM THE EARLIER MESO DISCUSSION ARE STILL VALID AND HAVE
BEEN BOLSTERED BY THE SPREAD OF SHOWERS WITH ISOLATED TSRA INTO THE
FCST AREA THIS AFTERNOON WITH LITTLE ADDITIONAL DEVELOPMENT DIRECTLY
WEST OVER IOWA SO FAR. 0-6 KM BULK SHEAR CONTINUES TO BE MARGINAL
OVER MOST OF THE LOCAL REGION BUT IS BUILDING TOWARD 40 KTS IN THE
AREA OF APPROACHING CONVECTION TO OUR SOUTHWEST UNDER THE LEADING
EDGE OF AN UPPER LEVEL JET. A FEW STORMS COULD BECOME ORGANIZED IN
SOUTHERN PORTIONS OF THE CWA...THOUGH THE SEVERE RISK OVERALL
APPEARS TO BE MARGINAL. TRENDS FOR THIS EVENING AND OVERNIGHT
ALSO WOULD CONTINUE TO FAVOR SOUTHERN PORTIONS OF THE CWA FOR THE
HEAVIEST RAINFALL AMOUNTS AND THE CORRESPONDING FLOOD RISK...AND
THIS ALSO IS WHERE THE MOST RAIN HAS FALLEN OVER THE PAST WEEK. FOR
THESE REASONS...AFTER COORDINATION WITH NEIGHBORS...WILL PLAN TO
DROP THE FLOOD WATCH FOR NORTHERN PORTIONS OF THE FORECAST AREA.
ALL OF THIS ACTIVITY IS BEING DRIVEN BY RICH BOUNDARY LAYER GULF
MOISTURE WRAPPING AROUND THE WESTERN SIDE OF A BERMUDA HIGH...AND
AHEAD OF AN APPROACHING FRONTAL ZONE TIED TO LOW PRESSURE OVER THE
DAKOTAS. THIS FRONTAL ZONE PUSHES THROUGH THE AREA SATURDAY NIGHT
AND USHERS IN COOLER AND DRIER AIR FOR THE FIRST HALF OF NEXT WEEK.
UNSETTLED WEATHER WILL PERSIST UNTIL THAT TIME WITH THE FOCUS
GRADUALLY SHIFTING EASTWARD. SHOWER AND THUNDERSTORM FORECAST
TRENDS FOR THIS EVENING AND OVERNIGHT ARE BASED ON CURRENT ACTIVITY
AND THE IDEA OF INCREASING DEVELOPMENT SUPPORTED BY LOW LEVEL
MOISTURE CONVERGENCE BEING DEPICTED IN THE RAP MODEL. IF THESE RAP
FIELDS CONTINUE TO BE VALID TOWARD MORNING...THE NORTHWEST HALF OF
THE AREA WOULD APPEAR TO DRY OUT BY MIDNIGHT AND REMAIN SO INTO THE
MORNING HOURS. THIS TREND ALSO IS SUPPORTED BY THE LATEST
NAM/ECMWF/GFS QPF FIELDS. CHANCES THEN INCREASE AGAIN DURING THE
DAY TOMORROW AHEAD OF THE APPROACHING UPPER LEVEL VORT MAX AND THE
SURFACE FRONTAL ZONE.
AFTER A COOLER AND DRIER END TO THE WEEKEND AND START TO THE WORK
WEEK...THE NEXT UPPER TROUGH AND SFC LOW BEGIN TO APPROACH THE
AREA TOWARD THE MIDDLE OF NEXT WEEK ALONG THE SIMILAR DAKOTAS TRACK
THAT WE HAVE SEEN WITH THE CURRENT SYSTEM. SFC WINDS TURNING
SOUTHEAST BY WEDNESDAY AND SOUTH BY THURSDAY WOULD ALLOW WARM MOIST
GULF AIR TO START WORKING BACK INTO THE AREA FOR LATE NEXT
WEEK...BUT AT THIS RANGE WILL ONLY PLAN TO CARRY CHANCE POPS.
LENNING
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 22Z...
* WINDS MAY BACK TO SE FOR TIME EARLY THIS EVENING
* CHANCE OF MVFR CIGS DEVELOPING THIS EVENING
* CHANCE OF SHRA/TSRA AGAIN SAT AFTERNOON
IZZI
//DISCUSSION...UPDATED 22Z...
HAVE REMOVED PRECIP FOR TONIGHT WITH AXIS OF MOST ORGANIZED
PRECIPITATION LIKELY TO REMAIN WELL SOUTH OF THE CHGO TERMINALS.
AM CLOSELY WATCHING AREA OF DEVELOPING LOWER END MVFR CIGS OVER
WC IL...IF THIS AREA CONTINUES TO EXPAND MAY NEED TO INTRODUCE
SOME MVFR CIGS LATER THIS EVENING INTO THE OVERNIGHT HOURS.
IZZI
UPDATED 18Z...
THE ACTIVE PERIOD CONTINUES BUT THERE IS VERY HIGH UNCERTAINTY
REGARDING WHERE AND WHEN CONVECTION WILL OCCUR TODAY. TEMPS HAVE
CLIMBED INTO THE 70S WITH DEWPOINTS IN THE 60S WHICH SUGGESTS
FAVORABLE CONDITIONS. A LOW PRESSURE SYSTEM IS OVER SOUTH DAKOTA
AND A LEFT OVER CONVECTIVE SYSTEM IS OVER NE MO/SE IA/W IL. SHOWERS
ARE SLOWLY MOVING NORTHEAST WITH A FEW CONVECTIVE CELLS FORMING OVER
FORD COUNTY IL IN THE LAST FEW MINUTES. EXPECTING THUNDERSTORMS TO
DEVELOP ACROSS NORTH CENTRAL IL AND PUSH EAST THROUGH THE EASTERN
TERMINALS. SINCE THE AXIS OF BEST INSTABILITY IS EAST OF RFD...KEPT
TS OUT OF RFD. THAT BEING SAID RFD MAY SEE A FEW STRAY SHOWERS OVER
THE NEXT FEW HOURS. GUSTY S WINDS ARE EXPECTED BUT MAY SEE A BRIEF
SHIFT TO SSE WINDS BEHIND THE THUNDERSTORMS.
EXPECTING A NARROW WINDOW OF TSRA OF ABOUT AN HOUR...FOLLOWED BY
SHOWERS. THE AREA WILL REMAIN UNSTABLE OVERNIGHT WITH SCATTERED
SHOWERS EXPECTED OVERNIGHT. ANOTHER ROUND OF TSRA AND SHOWERS IS
EXPECTED LATE SATURDAY AFTERNOON/EARLY AS THE LOW PRESSURE SYSTEM
PASSES TO THE NORTH AND ITS COLD FRONT APPROACHES FROM THE WEST.
STRONG S WINDS ARE ONCE AGAIN EXPECTED TOMORROW...BUT GUSTS WILL NOT
BE AS STRONG.
JEE
//ORD AND MDW CONFIDENCE...UPDATED 22Z...
* MEDIUM CONFIDENCE IN WINDS THIS EVENING
* LOW/MEDIUM CONFIDENCE IN CIGS TONIGHT
* LOW CONFIDENCE IN TSRA CHANCES SATURDAY
IZZI
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...CHC OF SHRA DURING THE EVE. MVFR POSSIBLE.
SUNDAY...SLT CHC OF MORNING SHRA.
MONDAY...VFR LIKELY.
TUESDAY...CHC OF MORNING MVFR.
WEDNESDAY & THURSDAY...CHC OF TSRA.
MTF
&&
.MARINE...
222 PM CDT
AN AREA OF LOW PRESSURE THAT HAS PERSISTED OVER THE NORTHERN PLAINS
WILL FINALLY BEGIN TO MOVE EAST TONIGHT...PASSING OVER NORTHERN LAKE
MICHIGAN LATE SATURDAY EVENING WITH A TRAILING COLD FRONT TURNING
MODERATE SOUTHERLY WINDS OF 15 TO 25 KT TO NORTHWESTERLY. MOIST FLOW
AHEAD OF THE FRONT HAS ALREADY LED TO DENSE FOG OVER MUCH OF THE
LAKE WHICH IS EXPECTED TO PERSIST UNTIL THE COLD FRONT PASSES
SATURDAY NIGHT. WINDS SHOULD THEN DIMINISH THROUGH THE DAY SUNDAY AS
HIGH PRESSURE BUILDS IN FROM THE WEST...BECOMING CENTERED OVER LAKE
MICHIGAN ON MONDAY. LOW PRESSURE WILL DEVELOP OVER THE CENTRAL
PLAINS MONDAY...THEN LIFT NORTHEAST TO LAKE MICHIGAN LATE THURSDAY
INTO EARLY FRIDAY.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ021-ILZ022-ILZ023-ILZ032-ILZ033-ILZ039
UNTIL 7 PM SATURDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 7
PM SATURDAY.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ868-LMZ870-
LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 PM SATURDAY.
SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 10 PM FRIDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
337 PM CDT FRI MAY 31 2013
.DISCUSSION...
336 PM CDT
THOUGHTS FROM THE EARLIER MESO DISCUSSION ARE STILL VALID AND HAVE
BEEN BOLSTERED BY THE SPREAD OF SHOWERS WITH ISOLATED TSRA INTO THE
FCST AREA THIS AFTERNOON WITH LITTLE ADDITIONAL DEVELOPMENT DIRECTLY
WEST OVER IOWA SO FAR. 0-6 KM BULK SHEAR CONTINUES TO BE MARGINAL
OVER MOST OF THE LOCAL REGION BUT IS BUILDING TOWARD 40 KTS IN THE
AREA OF APPROACHING CONVECTION TO OUR SOUTHWEST UNDER THE LEADING
EDGE OF AN UPPER LEVEL JET. A FEW STORMS COULD BECOME ORGANIZED IN
SOUTHERN PORTIONS OF THE CWA...THOUGH THE SEVERE RISK OVERALL
APPEARS TO BE MARGINAL. TRENDS FOR THIS EVENING AND OVERNIGHT
ALSO WOULD CONTINUE TO FAVOR SOUTHERN PORTIONS OF THE CWA FOR THE
HEAVIEST RAINFALL AMOUNTS AND THE CORRESPONDING FLOOD RISK...AND
THIS ALSO IS WHERE THE MOST RAIN HAS FALLEN OVER THE PAST WEEK. FOR
THESE REASONS...AFTER COORDINATION WITH NEIGHBORS...WILL PLAN TO
DROP THE FLOOD WATCH FOR NORTHERN PORTIONS OF THE FORECAST AREA.
ALL OF THIS ACTIVITY IS BEING DRIVEN BY RICH BOUNDARY LAYER GULF
MOISTURE WRAPPING AROUND THE WESTERN SIDE OF A BERMUDA HIGH...AND
AHEAD OF AN APPROACHING FRONTAL ZONE TIED TO LOW PRESSURE OVER THE
DAKOTAS. THIS FRONTAL ZONE PUSHES THROUGH THE AREA SATURDAY NIGHT
AND USHERS IN COOLER AND DRIER AIR FOR THE FIRST HALF OF NEXT WEEK.
UNSETTLED WEATHER WILL PERSIST UNTIL THAT TIME WITH THE FOCUS
GRADUALLY SHIFTING EASTWARD. SHOWER AND THUNDERSTORM FORECAST
TRENDS FOR THIS EVENING AND OVERNIGHT ARE BASED ON CURRENT ACTIVITY
AND THE IDEA OF INCREASING DEVELOPMENT SUPPORTED BY LOW LEVEL
MOISTURE CONVERGENCE BEING DEPICTED IN THE RAP MODEL. IF THESE RAP
FIELDS CONTINUE TO BE VALID TOWARD MORNING...THE NORTHWEST HALF OF
THE AREA WOULD APPEAR TO DRY OUT BY MIDNIGHT AND REMAIN SO INTO THE
MORNING HOURS. THIS TREND ALSO IS SUPPORTED BY THE LATEST
NAM/ECMWF/GFS QPF FIELDS. CHANCES THEN INCREASE AGAIN DURING THE
DAY TOMORROW AHEAD OF THE APPROACHING UPPER LEVEL VORT MAX AND THE
SURFACE FRONTAL ZONE.
AFTER A COOLER AND DRIER END TO THE WEEKEND AND START TO THE WORK
WEEK...THE NEXT UPPER TROUGH AND SFC LOW BEGIN TO APPROACH THE
AREA TOWARD THE MIDDLE OF NEXT WEEK ALONG THE SIMILAR DAKOTAS TRACK
THAT WE HAVE SEEN WITH THE CURRENT SYSTEM. SFC WINDS TURNING
SOUTHEAST BY WEDNESDAY AND SOUTH BY THURSDAY WOULD ALLOW WARM MOIST
GULF AIR TO START WORKING BACK INTO THE AREA FOR LATE NEXT
WEEK...BUT AT THIS RANGE WILL ONLY PLAN TO CARRY CHANCE POPS.
LENNING
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* GUSTY S WINDS EXPECTED THROUGH THIS AFTN WITH A BRIEF PERIOD OF
SSE WINDS PSBL BEHIND TSRA/SHRA.
* SHRA OR TSRA PSBL THIS AFTN WITH MVFR VSBY PSBL WITH TSRA.
* SCT SHOWERS OVERNIGHT.
* ANOTHER ROUND OF TSRA/SHRA EXPECTED TOMORROW AFTN.
JEE
//DISCUSSION...UPDATED 18Z...
THE ACTIVE PERIOD CONTINUES BUT THERE IS VERY HIGH UNCERTAINTY
REGARDING WHERE AND WHEN CONVECTION WILL OCCUR TODAY. TEMPS HAVE
CLIMBED INTO THE 70S WITH DEWPOINTS IN THE 60S WHICH SUGGESTS
FAVORABLE CONDITIONS. A LOW PRESSURE SYSTEM IS OVER SOUTH DAKOTA
AND A LEFT OVER CONVECTIVE SYSTEM IS OVER NE MO/SE IA/W IL. SHOWERS
ARE SLOWLY MOVING NORTHEAST WITH A FEW CONVECTIVE CELLS FORMING OVER
FORD COUNTY IL IN THE LAST FEW MINUTES. EXPECTING THUNDERSTORMS TO
DEVELOP ACROSS NORTH CENTRAL IL AND PUSH EAST THROUGH THE EASTERN
TERMINALS. SINCE THE AXIS OF BEST INSTABILITY IS EAST OF RFD...KEPT
TS OUT OF RFD. THAT BEING SAID RFD MAY SEE A FEW STRAY SHOWERS OVER
THE NEXT FEW HOURS. GUSTY S WINDS ARE EXPECTED BUT MAY SEE A BRIEF
SHIFT TO SSE WINDS BEHIND THE THUNDERSTORMS.
EXPECTING A NARROW WINDOW OF TSRA OF ABOUT AN HOUR...FOLLOWED BY
SHOWERS. THE AREA WILL REMAIN UNSTABLE OVERNIGHT WITH SCATTERED
SHOWERS EXPECTED OVERNIGHT. ANOTHER ROUND OF TSRA AND SHOWERS IS
EXPECTED LATE SATURDAY AFTERNOON/EARLY AS THE LOW PRESSURE SYSTEM
PASSES TO THE NORTH AND ITS COLD FRONT APPROACHES FROM THE WEST.
STRONG S WINDS ARE ONCE AGAIN EXPECTED TOMORROW...BUT GUSTS WILL NOT
BE AS STRONG.
JEE
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM CONFIDENCE IN PRECIP AFFECTING THE TERMINALS.
* LOW CONFIDENCE IN TIMING AND DURATION.
* LOW CONFIDENCE IN SHRA COVERAGE TONIGHT.
* MEDIUM CONFIDENCE IN TIMING OF SHRA/TSRA TOMORROW AFTERNOON.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
JEE
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...CHC OF SHRA DURING THE EVE. MVFR POSSIBLE.
SUNDAY...SLT CHC OF MORNING SHRA.
MONDAY...VFR LIKELY.
TUESDAY...CHC OF MORNING MVFR.
WEDNESDAY & THURSDAY...CHC OF TSRA.
MTF
&&
.MARINE...
222 PM CDT
AN AREA OF LOW PRESSURE THAT HAS PERSISTED OVER THE NORTHERN PLAINS
WILL FINALLY BEGIN TO MOVE EAST TONIGHT...PASSING OVER NORTHERN LAKE
MICHIGAN LATE SATURDAY EVENING WITH A TRAILING COLD FRONT TURNING
MODERATE SOUTHERLY WINDS OF 15 TO 25 KT TO NORTHWESTERLY. MOIST FLOW
AHEAD OF THE FRONT HAS ALREADY LED TO DENSE FOG OVER MUCH OF THE
LAKE WHICH IS EXPECTED TO PERSIST UNTIL THE COLD FRONT PASSES
SATURDAY NIGHT. WINDS SHOULD THEN DIMINISH THROUGH THE DAY SUNDAY AS
HIGH PRESSURE BUILDS IN FROM THE WEST...BECOMING CENTERED OVER LAKE
MICHIGAN ON MONDAY. LOW PRESSURE WILL DEVELOP OVER THE CENTRAL
PLAINS MONDAY...THEN LIFT NORTHEAST TO LAKE MICHIGAN LATE THURSDAY
INTO EARLY FRIDAY.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 7 PM SATURDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 7
PM SATURDAY.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ868-LMZ870-
LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 PM SATURDAY.
SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 7 PM FRIDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
257 PM CDT FRI MAY 31 2013
.MESOSCALE DISCUSSION...
INITIAL LOOK AT THE ATMOSPHERE IN PREPARATION OF AFTERNOON/EVENING
CONVECTION. SUPPORT FOR WIDESPREAD SEVERE APPEARS TO BE LESS
PRONOUNCED THAN EARLIER SIGNALS HAD SUGGESTED. A MINIMA OF 0-6KM
BULK SHEAR EXISTS EARLY THIS AFTERNOON ACROSS
NORTHCENTRAL/NORTHEAST ILLINOIS STRETCHING INTO NORTHWEST INDIANA.
ALONG THE WESTERN PERIPHERY OF THIS MINIMA IS AN AXIS OF MUCH
HIGHER SHEAR AROUND 70KTS IN IOWA...TO NEARLY 80KTS STRETCHING
SOUTH INTO CENTRAL MISSOURI. VISIBLE IMAGERY SHOWS CONSIDERABLE
CLOUD COVER...REMNANTS/BLOWOFF OF EARLIER CONVECTION TO THE
SOUTHWEST...LIFTING NORTHEAST ACROSS THE CWFA AT THIS TIME. THIS
WILL INHIBIT SFC CAPE FROM GETTING OUT OF CONTROL THROUGH EARLY
THIS AFTERNOON...AND TOGETHER WITH THE MARGINAL SHEAR WOULD TEND
TO LIMIT THE LOCAL POTENTIAL FOR ORGANIZED CONVECTION OVER THE
NEXT FEW HOURS.
MORNING CONVECTION IN MISSOURI CORRELATED TO AN AXIS OF LOW LEVEL
MOISTURE CONVERGENCE AND A WEAK TROUGH DEPICTED AT 850 MB. LATEST
FIELDS FROM THE RAP MODEL SHOW THIS TROUGH AND THE WESTERN FOCUS
FOR THIS MOISTURE CONVERGENCE EXPANDING OUT OF THE SAINT LOUIS
AREA ACROSS ILLINOIS AND WORKING INTO THE CHICAGO METRO AREA BY
LATE AFTERNOON...22Z TO 00Z...WHILE GRADUALLY BECOMING LESS
FOCUSED. HI-RES GUIDANCE IS SUGGESTING THAT AS THIS CONVECTION
BEGINS TO LIFT THROUGH SW IL...IT WILL EXPAND ALONG A LINE
STRETCHING FROM SAINT LOUIS THROUGH BLOOMINGTON TO KANKAKEE AND
TOWARD MICHIGAN CITY.
A SMALLER AREA OF LATE MORNING AND EARLY AFTERNOON ISOLATED
STORMS OVER IOWA ALSO IS NICELY CORRELATED TO AN AXIS OF MOISTURE
CONVERGENCE IN THE RAP...BUT WAS MUCH LESS PRONOUNCED AND
MIGRATING MORE TO THE NORTH RATHER THAN EAST INTO ILLINOIS. THIS
CONVECTION WAS CLOSER TO THE 500MB VORT MAX AND IN AN AREA OF
ANTICIPATED STEEPENING LAPSE RATES THROUGHOUT THE AFTN. AS THE
TROUGH AXIS SLOWLY SLIDES EAST...SOME OF THIS MAY PUSH INTO
NORTHWEST IL BUT MAY NOT HAVE THE LONGEVITY TO CONTINUE ACROSS
NORTHCENTRAL/NORTHEAST IL.
BEACHLER/LENNING
&&
.DISCUSSION...
328 AM...MAIN FORECAST CONCERN AND CHALLENGE REMAINS CONVECTIVE
TRENDS/TIMING THROUGH SATURDAY EVENING ALONG WITH POTENTIAL FOR
SEVERE WEATHER AND HEAVY RAIN/FLOODING.
WAVE OF SHOWERS WITH SOME EMBEDDED THUNDER WILL CONTINUE LIFTING
NORTHEAST AWAY FROM THE AREA EARLY THIS MORNING WITH SUBSIDENCE
INTO THE MID MORNING HOURS EXPECTED TO BRING SEVERAL HOURS OF DRY
WEATHER. ATTENTION THEN SHIFTS TO CONVECTION OVER NORTHEAST
KANSAS/NORTHWEST MISSOURI. MOST RECENT HRRR/RAP GUIDANCE SEEMS IN
BETTER AGREEMENT WITH 00Z SUITE OF MODELS SHOWING THIS ACTIVITY
SPREADING EAST/NORTHEAST AS THE MAIN SHORTWAVE LIFTS NORTHEAST...
THEN SUGGESTS RAPID DEVELOPMENT ACROSS WESTERN AND NORTH CENTRAL
IL THIS AFTERNOON...PERHAPS EARLY THIS AFTERNOON. HOWEVER...
THERE STILL REMAINS SOME UNCERTAINTY REGARDING WHERE CONVECTION
DEVELOPS AND WHETHER IT AFFECTS ALL OR PART OF THE CWA. CONFIDENCE
INCREASES ACROSS THE SOUTHERN HALF/TWO THIRDS OF THE AREA.
WITH THE EXPECTATION THAT THIS MORNING WILL END UP BEING MAINLY
DRY AND EVENTUALLY PARTLY/MOSTLY SUNNY...TEMPS REACHING LOWER 80S
SEEMS ON TRACK ALONG WITH DEWPOINTS REBOUNDING BACK INTO THE
MID/UPPER 60S. SUFFICIENT SHEAR AND STRONG LAPSE RATES COMBINED
WITH THE VERY MOIST/UNSTABLE LOW LEVELS WILL SUPPORT SEVERE
WEATHER ACROSS THE ENTIRE AREA WITH THE MAIN THREAT APPEARING TO
BE DAMAGING WINDS WITH ASSOCIATED LINES/BOWING SEGMENTS. THOUGH
LARGE HAIL WITH STRONGER CORES AND ISOLATED TORNADOES WILL REMAIN
POSSIBLE.
CONVECTION WILL THEN SHIFT EAST THIS EVENING/OVERNIGHT. AS THE
UPPER TROUGH MOVES CLOSER TO THE WESTERN LAKES SATURDAY...ANOTHER
WAVE IS EXPECTED TO LIFT NORTHEAST SATURDAY BUT LIKELY BE A LITTLE
FURTHER EAST WITH CONVECTION LIKELY AFFECTING MAINLY EASTERN IL
AND NORTHWEST INDIANA...PERHAPS ALONG/EAST OF THE I-55 OR I-57
CORRIDORS. SEVERE WEATHER WILL ONCE AGAIN BE POSSIBLE SATURDAY
AFTERNOON INTO SATURDAY EVENING.
NO CHANGES PLANNED TO THE FLASH FLOOD WATCH WHICH IS IN EFFECT FOR
THE ENTIRE AREA THROUGH SATURDAY EVENING. FORECAST STORM TOTAL
RAINFALL...FROM THIS MORNING THROUGH SATURDAY EVENING...RANGES
FROM ABOUT AN INCH NEAR THE WI/IL BORDER TO 2-2.5 INCHES FROM A
CHICAGO/PERU LINE SOUTH. SOME AREAS WILL LIKELY SEE LESS AND SOME
AREAS MAY SEE MORE. INDIVIDUAL STORM MOTION WILL PROBABLY BE FAST
ENOUGH THAT WHILE HEAVY/TORRENTIAL RAIN WILL FALL...ITS DURATION
COULD BE SHORT. BUT IF THE STORMS BEGIN TO TRAIN OVER THE SAME
AREAS...WITH RAINFALL RATES OF 1 TO 2+ INCHES/HOUR...ON ALREADY
SATURATED GROUND...THEN FLASH FLOODING MAY BE POSSIBLE.
AS THE UPPER TROUGH/SURFACE LOW FINALLY DEPART SUNDAY...ONE LAST
WAVE PIVOTING AROUND THE WESTERN LAKES COULD PRODUCE SOME SHOWERS
SUNDAY MORNING. BROAD BUT WEAK HIGH PRESSURE THEN BUILDS ACROSS
THE LAKES SUNDAY AFTERNOON THROUGH MONDAY WITH A SHOT OF COOLER
AIR. WHILE HIGHS ON SUNDAY ARE ONLY EXPECTED TO BE IN THE
60S...LOWER 70S SOUTH...WINDS WILL TURN OFF THE LAKE SUNDAY
AFTERNOON...THUS COOLER/FALLING TEMPS AT THE LAKE SUNDAY
AFTERNOON. LOWS THEN DROP INTO THE 40S IN MANY AREAS MONDAY
MORNING AND POSSIBLY TUESDAY MORNING AS WELL. SEVERAL DAYS OF
EASTERLY WINDS WILL KEEP THE LAKE SHORE AREAS COOLER NEXT WEEK.
PATTERN APPEARS TO TURN MORE ACTIVE AGAIN TUESDAY INTO WEDNESDAY
AS ANOTHER SLOW MOVING UPPER LOW TRACKS ACROSS THE PLAINS THOUGH
ITS STILL FAIRLY EARLY TO DETERMINE WHERE AND WHEN THIS LOW WILL
MOVE THOUGH HAVE INCLUDED CHANCE POPS INTO MID/LATE WEEK AS THIS
NEXT SYSTEM POTENTIALLY APPROACHES. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* GUSTY S WINDS EXPECTED THROUGH THIS AFTN WITH A BRIEF PERIOD OF
SSE WINDS PSBL BEHIND TSRA/SHRA.
* SHRA OR TSRA PSBL THIS AFTN WITH MVFR VSBY PSBL WITH TSRA.
* SCT SHOWERS OVERNIGHT.
* ANOTHER ROUND OF TSRA/SHRA EXPECTED TOMORROW AFTN.
JEE
//DISCUSSION...UPDATED 18Z...
THE ACTIVE PERIOD CONTINUES BUT THERE IS VERY HIGH UNCERTAINTY
REGARDING WHERE AND WHEN CONVECTION WILL OCCUR TODAY. TEMPS HAVE
CLIMBED INTO THE 70S WITH DEWPOINTS IN THE 60S WHICH SUGGESTS
FAVORABLE CONDITIONS. A LOW PRESSURE SYSTEM IS OVER SOUTH DAKOTA
AND A LEFT OVER CONVECTIVE SYSTEM IS OVER NE MO/SE IA/W IL. SHOWERS
ARE SLOWLY MOVING NORTHEAST WITH A FEW CONVECTIVE CELLS FORMING OVER
FORD COUNTY IL IN THE LAST FEW MINUTES. EXPECTING THUNDERSTORMS TO
DEVELOP ACROSS NORTH CENTRAL IL AND PUSH EAST THROUGH THE EASTERN
TERMINALS. SINCE THE AXIS OF BEST INSTABILITY IS EAST OF RFD...KEPT
TS OUT OF RFD. THAT BEING SAID RFD MAY SEE A FEW STRAY SHOWERS OVER
THE NEXT FEW HOURS. GUSTY S WINDS ARE EXPECTED BUT MAY SEE A BRIEF
SHIFT TO SSE WINDS BEHIND THE THUNDERSTORMS.
EXPECTING A NARROW WINDOW OF TSRA OF ABOUT AN HOUR...FOLLOWED BY
SHOWERS. THE AREA WILL REMAIN UNSTABLE OVERNIGHT WITH SCATTERED
SHOWERS EXPECTED OVERNIGHT. ANOTHER ROUND OF TSRA AND SHOWERS IS
EXPECTED LATE SATURDAY AFTERNOON/EARLY AS THE LOW PRESSURE SYSTEM
PASSES TO THE NORTH AND ITS COLD FRONT APPROACHES FROM THE WEST.
STRONG S WINDS ARE ONCE AGAIN EXPECTED TOMORROW...BUT GUSTS WILL NOT
BE AS STRONG.
JEE
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM CONFIDENCE IN PRECIP AFFECTING THE TERMINALS.
* LOW CONFIDENCE IN TIMING AND DURATION.
* LOW CONFIDENCE IN SHRA COVERAGE TONIGHT.
* MEDIUM CONFIDENCE IN TIMING OF SHRA/TSRA TOMORROW AFTERNOON.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
JEE
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...CHC OF SHRA DURING THE EVE. MVFR POSSIBLE.
SUNDAY...SLT CHC OF MORNING SHRA.
MONDAY...VFR LIKELY.
TUESDAY...CHC OF MORNING MVFR.
WEDNESDAY & THURSDAY...CHC OF TSRA.
MTF
&&
.MARINE...
222 PM CDT
AN AREA OF LOW PRESSURE THAT HAS PERSISTED OVER THE NORTHERN PLAINS
WILL FINALLY BEGIN TO MOVE EAST TONIGHT...PASSING OVER NORTHERN LAKE
MICHIGAN LATE SATURDAY EVENING WITH A TRAILING COLD FRONT TURNING
MODERATE SOUTHERLY WINDS OF 15 TO 25 KT TO NORTHWESTERLY. MOIST FLOW
AHEAD OF THE FRONT HAS ALREADY LED TO DENSE FOG OVER MUCH OF THE
LAKE WHICH IS EXPECTED TO PERSIST UNTIL THE COLD FRONT PASSES
SATURDAY NIGHT. WINDS SHOULD THEN DIMINISH THROUGH THE DAY SUNDAY AS
HIGH PRESSURE BUILDS IN FROM THE WEST...BECOMING CENTERED OVER LAKE
MICHIGAN ON MONDAY. LOW PRESSURE WILL DEVELOP OVER THE CENTRAL
PLAINS MONDAY...THEN LIFT NORTHEAST TO LAKE MICHIGAN LATE THURSDAY
INTO EARLY FRIDAY.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 7 PM SATURDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 7
PM SATURDAY.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ868-LMZ870-
LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 PM SATURDAY.
SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 10 PM FRIDAY.
&&
$$
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
225 PM CDT FRI MAY 31 2013
.MESOSCALE DISCUSSION...
INITIAL LOOK AT THE ATMOSPHERE IN PREPARATION OF AFTERNOON/EVENING
CONVECTION. SUPPORT FOR WIDESPREAD SEVERE APPEARS TO BE LESS
PRONOUNCED THAN EARLIER SIGNALS HAD SUGGESTED. A MINIMA OF 0-6KM
BULK SHEAR EXISTS EARLY THIS AFTERNOON ACROSS NORTHCENTRAL/NORTHEAST
ILLINOIS STRETCHING INTO NORTHWEST INDIANA. ALONG THE WESTERN
PERIPHERY OF THIS MINIMA IS AN AXIS OF MUCH HIGHER SHEAR AROUND
70KTS IN IOWA...TO NEARLY 80KTS STRETCHING SOUTH INTO CENTRAL
MISSOURI. VISIBLE IMAGERY SHOWS CONSIDERABLE CLOUD
COVER...REMNANTS/BLOWOFF OF EARLIER CONVECTION TO THE
SOUTHWEST...LIFTING NORTHEAST ACROSS THE CWFA AT THIS TIME. THIS
WILL INHIBIT SFC CAPE FROM GETTING OUT OF CONTROL THROUGH EARLY
THIS AFTERNOON...AND TOGETHER WITH THE MARGINAL SHEAR WOULD TEND
TO LIMIT THE LOCAL POTENTIAL FOR ORGANIZED CONVECTION OVER THE
NEXT FEW HOURS.
MORNING CONVECTION IN MISSOURI CORRELATED TO AN AXIS OF LOW LEVEL
MOISTURE CONVERGENCE AND A WEAK TROUGH DEPICTED AT 850 MB. LATEST
FIELDS FROM THE RAP MODEL SHOW THIS TROUGH AND THE WESTERN FOCUS
FOR THIS MOISTURE CONVERGENCE EXPANDING OUT OF THE SAINT LOUIS
AREA ACROSS ILLINOIS AND WORKING INTO THE CHICAGO METRO AREA BY
LATE AFTERNOON...22Z TO 00Z...WHILE GRADUALLY BECOMING LESS
FOCUSED. HI-RES GUIDANCE IS SUGGESTING THAT AS THIS CONVECTION
BEGINS TO LIFT THROUGH SW IL...IT WILL EXPAND ALONG A LINE
STRETCHING FROM SAINT LOUIS THROUGH BLOOMINGTON TO KANKAKEE AND
TOWARD MICHIGAN CITY.
A SMALLER AREA OF LATE MORNING AND EARLY AFTERNOON ISOLATED
STORMS OVER IOWA ALSO IS NICELY CORRELATED TO AN AXIS OF MOISTURE
CONVERGENCE IN THE RAP...BUT WAS MUCH LESS PRONOUNCED AND
MIGRATING MORE TO THE NORTH RATHER THAN EAST INTO ILLINOIS. THIS
CONVECTION WAS CLOSER TO THE 500MB VORT MAX AND IN AN AREA OF
ANTICIPATED STEEPENING LAPSE RATES THROUGHOUT THE AFTN. AS THE
TROUGH AXIS SLOWLY SLIDES EAST...SOME OF THIS MAY PUSH INTO
NORTHWEST IL BUT MAY NOT HAVE THE LONGEVITY TO CONTINUE ACROSS
NORTHCENTRAL/NORTHEAST IL.
BEACHLER/LENNING
&&
.DISCUSSION...
328 AM...MAIN FORECAST CONCERN AND CHALLENGE REMAINS CONVECTIVE
TRENDS/TIMING THROUGH SATURDAY EVENING ALONG WITH POTENTIAL FOR
SEVERE WEATHER AND HEAVY RAIN/FLOODING.
WAVE OF SHOWERS WITH SOME EMBEDDED THUNDER WILL CONTINUE LIFTING
NORTHEAST AWAY FROM THE AREA EARLY THIS MORNING WITH SUBSIDENCE
INTO THE MID MORNING HOURS EXPECTED TO BRING SEVERAL HOURS OF DRY
WEATHER. ATTENTION THEN SHIFTS TO CONVECTION OVER NORTHEAST
KANSAS/NORTHWEST MISSOURI. MOST RECENT HRRR/RAP GUIDANCE SEEMS IN
BETTER AGREEMENT WITH 00Z SUITE OF MODELS SHOWING THIS ACTIVITY
SPREADING EAST/NORTHEAST AS THE MAIN SHORTWAVE LIFTS NORTHEAST...
THEN SUGGESTS RAPID DEVELOPMENT ACROSS WESTERN AND NORTH CENTRAL
IL THIS AFTERNOON...PERHAPS EARLY THIS AFTERNOON. HOWEVER...
THERE STILL REMAINS SOME UNCERTAINTY REGARDING WHERE CONVECTION
DEVELOPS AND WHETHER IT AFFECTS ALL OR PART OF THE CWA. CONFIDENCE
INCREASES ACROSS THE SOUTHERN HALF/TWO THIRDS OF THE AREA.
WITH THE EXPECTATION THAT THIS MORNING WILL END UP BEING MAINLY
DRY AND EVENTUALLY PARTLY/MOSTLY SUNNY...TEMPS REACHING LOWER 80S
SEEMS ON TRACK ALONG WITH DEWPOINTS REBOUNDING BACK INTO THE
MID/UPPER 60S. SUFFICIENT SHEAR AND STRONG LAPSE RATES COMBINED
WITH THE VERY MOIST/UNSTABLE LOW LEVELS WILL SUPPORT SEVERE
WEATHER ACROSS THE ENTIRE AREA WITH THE MAIN THREAT APPEARING TO
BE DAMAGING WINDS WITH ASSOCIATED LINES/BOWING SEGMENTS. THOUGH
LARGE HAIL WITH STRONGER CORES AND ISOLATED TORNADOES WILL REMAIN
POSSIBLE.
CONVECTION WILL THEN SHIFT EAST THIS EVENING/OVERNIGHT. AS THE
UPPER TROUGH MOVES CLOSER TO THE WESTERN LAKES SATURDAY...ANOTHER
WAVE IS EXPECTED TO LIFT NORTHEAST SATURDAY BUT LIKELY BE A LITTLE
FURTHER EAST WITH CONVECTION LIKELY AFFECTING MAINLY EASTERN IL
AND NORTHWEST INDIANA...PERHAPS ALONG/EAST OF THE I-55 OR I-57
CORRIDORS. SEVERE WEATHER WILL ONCE AGAIN BE POSSIBLE SATURDAY
AFTERNOON INTO SATURDAY EVENING.
NO CHANGES PLANNED TO THE FLASH FLOOD WATCH WHICH IS IN EFFECT FOR
THE ENTIRE AREA THROUGH SATURDAY EVENING. FORECAST STORM TOTAL
RAINFALL...FROM THIS MORNING THROUGH SATURDAY EVENING...RANGES
FROM ABOUT AN INCH NEAR THE WI/IL BORDER TO 2-2.5 INCHES FROM A
CHICAGO/PERU LINE SOUTH. SOME AREAS WILL LIKELY SEE LESS AND SOME
AREAS MAY SEE MORE. INDIVIDUAL STORM MOTION WILL PROBABLY BE FAST
ENOUGH THAT WHILE HEAVY/TORRENTIAL RAIN WILL FALL...ITS DURATION
COULD BE SHORT. BUT IF THE STORMS BEGIN TO TRAIN OVER THE SAME
AREAS...WITH RAINFALL RATES OF 1 TO 2+ INCHES/HOUR...ON ALREADY
SATURATED GROUND...THEN FLASH FLOODING MAY BE POSSIBLE.
AS THE UPPER TROUGH/SURFACE LOW FINALLY DEPART SUNDAY...ONE LAST
WAVE PIVOTING AROUND THE WESTERN LAKES COULD PRODUCE SOME SHOWERS
SUNDAY MORNING. BROAD BUT WEAK HIGH PRESSURE THEN BUILDS ACROSS
THE LAKES SUNDAY AFTERNOON THROUGH MONDAY WITH A SHOT OF COOLER
AIR. WHILE HIGHS ON SUNDAY ARE ONLY EXPECTED TO BE IN THE
60S...LOWER 70S SOUTH...WINDS WILL TURN OFF THE LAKE SUNDAY
AFTERNOON...THUS COOLER/FALLING TEMPS AT THE LAKE SUNDAY
AFTERNOON. LOWS THEN DROP INTO THE 40S IN MANY AREAS MONDAY
MORNING AND POSSIBLY TUESDAY MORNING AS WELL. SEVERAL DAYS OF
EASTERLY WINDS WILL KEEP THE LAKE SHORE AREAS COOLER NEXT WEEK.
PATTERN APPEARS TO TURN MORE ACTIVE AGAIN TUESDAY INTO WEDNESDAY
AS ANOTHER SLOW MOVING UPPER LOW TRACKS ACROSS THE PLAINS THOUGH
ITS STILL FAIRLY EARLY TO DETERMINE WHERE AND WHEN THIS LOW WILL
MOVE THOUGH HAVE INCLUDED CHANCE POPS INTO MID/LATE WEEK AS THIS
NEXT SYSTEM POTENTIALLY APPROACHES. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* GUSTY S WINDS EXPECTED THIS AFTN WITH A BRIEF PERIOD OF SSE
WINDS PSBL BEHIND TSRA.
* BRIEF PERIOD OF TSRA THIS AFTN WITH MVFR VSBY PSBL.
* SHRA EXPECTED BEHIND TSRA WITH SCT SHOWERS OVERNIGHT.
* ANOTHER ROUND OF TSRA/SHRA EXPECTED TOMORROW AFTN.
JEE
//DISCUSSION...UPDATED 18Z...
THE ACTIVE PERIOD CONTINUES BUT THERE IS VERY HIGH UNCERTAINTY
REGARDING WHERE AND WHEN CONVECTION WILL OCCUR TODAY. TEMPS HAVE
CLIMBED INTO THE 70S WITH DEWPOINTS IN THE 60S WHICH SUGGESTS
FAVORABLE CONDITIONS. A LOW PRESSURE SYSTEM IS OVER SOUTH DAKOTA
AND A LEFT OVER CONVECTIVE SYSTEM IS OVER NE MO/SE IA/W IL. SHOWERS
ARE SLOWLY MOVING NORTHEAST WITH A FEW CONVECTIVE CELLS FORMING OVER
FORD COUNTY IL IN THE LAST FEW MINUTES. EXPECTING THUNDERSTORMS TO
DEVELOP ACROSS NORTH CENTRAL IL AND PUSH EAST THROUGH THE EASTERN
TERMINALS. SINCE THE AXIS OF BEST INSTABILITY IS EAST OF RFD...KEPT
TS OUT OF RFD. THAT BEING SAID RFD MAY SEE A FEW STRAY SHOWERS OVER
THE NEXT FEW HOURS. GUSTY S WINDS ARE EXPECTED BUT MAY SEE A BRIEF
SHIFT TO SSE WINDS BEHIND THE THUNDERSTORMS.
EXPECTING A NARROW WINDOW OF TSRA OF ABOUT AN HOUR...FOLLOWED BY
SHOWERS. THE AREA WILL REMAIN UNSTABLE OVERNIGHT WITH SCATTERED
SHOWERS EXPECTED OVERNIGHT. ANOTHER ROUND OF TSRA AND SHOWERS IS
EXPECTED LATE SATURDAY AFTERNOON/EARLY AS THE LOW PRESSURE SYSTEM
PASSES TO THE NORTH AND ITS COLD FRONT APPROACHES FROM THE WEST.
STRONG S WINDS ARE ONCE AGAIN EXPECTED TOMORROW...BUT GUSTS WILL NOT
BE AS STRONG.
JEE
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH CONFIDENCE IN PRECIP AFFECTING THE AIRPORTS THIS AFTERNOON.
* LOW CONFIDENCE IN TIMING AND DURATION.
* LOW CONFIDENCE IN SHRA COVERAGE TONIGHT.
* MEDIUM CONFIDENCE IN TIMING OF SHRA/TSRA TOMORROW AFTERNOON.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
JEE
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...CHC OF SHRA DURING THE EVE. MVFR POSSIBLE.
SUNDAY...SLT CHC OF MORNING SHRA.
MONDAY...VFR LIKELY.
TUESDAY...CHC OF MORNING MVFR.
WEDNESDAY & THURSDAY...CHC OF TSRA.
MTF
&&
.MARINE...
222 PM CDT
AN AREA OF LOW PRESSURE THAT HAS PERSISTED OVER THE NORTHERN PLAINS
WILL FINALLY BEGIN TO MOVE EAST TONIGHT...PASSING OVER NORTHERN LAKE
MICHIGAN LATE SATURDAY EVENING WITH A TRAILING COLD FRONT TURNING
MODERATE SOUTHERLY WINDS OF 15 TO 25 KT TO NORTHWESTERLY. MOIST FLOW
AHEAD OF THE FRONT HAS ALREADY LED TO DENSE FOG OVER MUCH OF THE
LAKE WHICH IS EXPECTED TO PERSIST UNTIL THE COLD FRONT PASSES
SATURDAY NIGHT. WINDS SHOULD THEN DIMINISH THROUGH THE DAY SUNDAY AS
HIGH PRESSURE BUILDS IN FROM THE WEST...BECOMING CENTERED OVER LAKE
MICHIGAN ON MONDAY. LOW PRESSURE WILL DEVELOP OVER THE CENTRAL
PLAINS MONDAY...THEN LIFT NORTHEAST TO LAKE MICHIGAN LATE THURSDAY
INTO EARLY FRIDAY.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 7 PM SATURDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 7
PM SATURDAY.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ868-LMZ870-
LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 PM SATURDAY.
SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 7 PM FRIDAY.
&&
$$
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
128 PM CDT FRI MAY 31 2013
.MESOSCALE DISCUSSION...115 PM CDT
INITIAL LOOK AT THE ATMOSPHERE IN PREPARATION OF AFTERNOON/EVENING
CONVECTION. SUPPORT FOR WIDESPREAD SEVERE APPEARS TO BE LESS
PRONOUNCED THAN EARLIER SIGNALS HAD SUGGESTED. A MINIMA OF 0-6KM
BULK SHEAR EXISTS EARLY THIS AFTERNOON ACROSS NORTHCENTRAL/NORTHEAST
ILLINOIS STRETCHING INTO NORTHWEST INDIANA. ALONG THE WESTERN
PERIPHERY OF THIS MINIMA IS AN AXIS OF MUCH HIGHER SHEAR AROUND
70KTS IN IOWA...TO NEARLY 80KTS STRETCHING SOUTH INTO CENTRAL
MISSOURI. VISIBLE IMAGERY SHOWS CONSIDERABLE CLOUD
COVER...REMNANTS/BLOWOFF OF EARLIER CONVECTION TO THE
SOUTHWEST...LIFTING NORTHEAST ACROSS THE CWFA AT THIS TIME. THIS
WILL INHIBIT SFC CAPE FROM GETTING OUT OF CONTROL THROUGH EARLY
THIS AFTERNOON...AND TOGETHER WITH THE MARGINAL SHEAR WOULD TEND
TO LIMIT THE LOCAL POTENTIAL FOR ORGANIZED CONVECTION OVER THE
NEXT FEW HOURS.
MORNING CONVECTION IN MISSOURI CORRELATED TO AN AXIS OF LOW LEVEL
MOISTURE CONVERGENCE AND A WEAK TROUGH DEPICTED AT 850 MB. LATEST
FIELDS FROM THE RAP MODEL SHOW THIS TROUGH AND THE WESTERN FOCUS
FOR THIS MOISTURE CONVERGENCE EXPANDING OUT OF THE SAINT LOUIS
AREA ACROSS ILLINOIS AND WORKING INTO THE CHICAGO METRO AREA BY
LATE AFTERNOON...22Z TO 00Z...WHILE GRADUALLY BECOMING LESS
FOCUSED. HI-RES GUIDANCE IS SUGGESTING THAT AS THIS CONVECTION
BEGINS TO LIFT THROUGH SW IL...IT WILL EXPAND ALONG A LINE
STRETCHING FROM SAINT LOUIS THROUGH BLOOMINGTON TO KANKAKEE AND
TOWARD MICHIGAN CITY.
A SMALLER AREA OF LATE MORNING AND EARLY AFTERNOON ISOLATED
STORMS OVER IOWA ALSO IS NICELY CORRELATED TO AN AXIS OF MOISTURE
CONVERGENCE IN THE RAP...BUT WAS MUCH LESS PRONOUNCED AND
MIGRATING MORE TO THE NORTH RATHER THAN EAST INTO ILLINOIS. THIS
CONVECTION WAS CLOSER TO THE 500MB VORT MAX AND IN AN AREA OF
ANTICIPATED STEEPENING LAPSE RATES THROUGHOUT THE AFTN. AS THE
TROUGH AXIS SLOWLY SLIDES EAST...SOME OF THIS MAY PUSH INTO
NORTHWEST IL BUT MAY NOT HAVE THE LONGEVITY TO CONTINUE ACROSS
NORTHCENTRAL/NORTHEAST IL.
BEACHLER/LENNING
&&
.DISCUSSION...
328 AM...MAIN FORECAST CONCERN AND CHALLENGE REMAINS CONVECTIVE
TRENDS/TIMING THROUGH SATURDAY EVENING ALONG WITH POTENTIAL FOR
SEVERE WEATHER AND HEAVY RAIN/FLOODING.
WAVE OF SHOWERS WITH SOME EMBEDDED THUNDER WILL CONTINUE LIFTING
NORTHEAST AWAY FROM THE AREA EARLY THIS MORNING WITH SUBSIDENCE
INTO THE MID MORNING HOURS EXPECTED TO BRING SEVERAL HOURS OF DRY
WEATHER. ATTENTION THEN SHIFTS TO CONVECTION OVER NORTHEAST
KANSAS/NORTHWEST MISSOURI. MOST RECENT HRRR/RAP GUIDANCE SEEMS IN
BETTER AGREEMENT WITH 00Z SUITE OF MODELS SHOWING THIS ACTIVITY
SPREADING EAST/NORTHEAST AS THE MAIN SHORTWAVE LIFTS NORTHEAST...
THEN SUGGESTS RAPID DEVELOPMENT ACROSS WESTERN AND NORTH CENTRAL
IL THIS AFTERNOON...PERHAPS EARLY THIS AFTERNOON. HOWEVER...
THERE STILL REMAINS SOME UNCERTAINTY REGARDING WHERE CONVECTION
DEVELOPS AND WHETHER IT AFFECTS ALL OR PART OF THE CWA. CONFIDENCE
INCREASES ACROSS THE SOUTHERN HALF/TWO THIRDS OF THE AREA.
WITH THE EXPECTATION THAT THIS MORNING WILL END UP BEING MAINLY
DRY AND EVENTUALLY PARTLY/MOSTLY SUNNY...TEMPS REACHING LOWER 80S
SEEMS ON TRACK ALONG WITH DEWPOINTS REBOUNDING BACK INTO THE
MID/UPPER 60S. SUFFICIENT SHEAR AND STRONG LAPSE RATES COMBINED
WITH THE VERY MOIST/UNSTABLE LOW LEVELS WILL SUPPORT SEVERE
WEATHER ACROSS THE ENTIRE AREA WITH THE MAIN THREAT APPEARING TO
BE DAMAGING WINDS WITH ASSOCIATED LINES/BOWING SEGMENTS. THOUGH
LARGE HAIL WITH STRONGER CORES AND ISOLATED TORNADOES WILL REMAIN
POSSIBLE.
CONVECTION WILL THEN SHIFT EAST THIS EVENING/OVERNIGHT. AS THE
UPPER TROUGH MOVES CLOSER TO THE WESTERN LAKES SATURDAY...ANOTHER
WAVE IS EXPECTED TO LIFT NORTHEAST SATURDAY BUT LIKELY BE A LITTLE
FURTHER EAST WITH CONVECTION LIKELY AFFECTING MAINLY EASTERN IL
AND NORTHWEST INDIANA...PERHAPS ALONG/EAST OF THE I-55 OR I-57
CORRIDORS. SEVERE WEATHER WILL ONCE AGAIN BE POSSIBLE SATURDAY
AFTERNOON INTO SATURDAY EVENING.
NO CHANGES PLANNED TO THE FLASH FLOOD WATCH WHICH IS IN EFFECT FOR
THE ENTIRE AREA THROUGH SATURDAY EVENING. FORECAST STORM TOTAL
RAINFALL...FROM THIS MORNING THROUGH SATURDAY EVENING...RANGES
FROM ABOUT AN INCH NEAR THE WI/IL BORDER TO 2-2.5 INCHES FROM A
CHICAGO/PERU LINE SOUTH. SOME AREAS WILL LIKELY SEE LESS AND SOME
AREAS MAY SEE MORE. INDIVIDUAL STORM MOTION WILL PROBABLY BE FAST
ENOUGH THAT WHILE HEAVY/TORRENTIAL RAIN WILL FALL...ITS DURATION
COULD BE SHORT. BUT IF THE STORMS BEGIN TO TRAIN OVER THE SAME
AREAS...WITH RAINFALL RATES OF 1 TO 2+ INCHES/HOUR...ON ALREADY
SATURATED GROUND...THEN FLASH FLOODING MAY BE POSSIBLE.
AS THE UPPER TROUGH/SURFACE LOW FINALLY DEPART SUNDAY...ONE LAST
WAVE PIVOTING AROUND THE WESTERN LAKES COULD PRODUCE SOME SHOWERS
SUNDAY MORNING. BROAD BUT WEAK HIGH PRESSURE THEN BUILDS ACROSS
THE LAKES SUNDAY AFTERNOON THROUGH MONDAY WITH A SHOT OF COOLER
AIR. WHILE HIGHS ON SUNDAY ARE ONLY EXPECTED TO BE IN THE
60S...LOWER 70S SOUTH...WINDS WILL TURN OFF THE LAKE SUNDAY
AFTERNOON...THUS COOLER/FALLING TEMPS AT THE LAKE SUNDAY
AFTERNOON. LOWS THEN DROP INTO THE 40S IN MANY AREAS MONDAY
MORNING AND POSSIBLY TUESDAY MORNING AS WELL. SEVERAL DAYS OF
EASTERLY WINDS WILL KEEP THE LAKE SHORE AREAS COOLER NEXT WEEK.
PATTERN APPEARS TO TURN MORE ACTIVE AGAIN TUESDAY INTO WEDNESDAY
AS ANOTHER SLOW MOVING UPPER LOW TRACKS ACROSS THE PLAINS THOUGH
ITS STILL FAIRLY EARLY TO DETERMINE WHERE AND WHEN THIS LOW WILL
MOVE THOUGH HAVE INCLUDED CHANCE POPS INTO MID/LATE WEEK AS THIS
NEXT SYSTEM POTENTIALLY APPROACHES. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* GUSTY S WINDS EXPECTED THIS AFTN WITH A BRIEF PERIOD OF SSE
WINDS PSBL BEHIND TSRA.
* BRIEF PERIOD OF TSRA THIS AFTN WITH MVFR VSBY PSBL.
* SHRA EXPECTED BEHIND TSRA WITH SCT SHOWERS OVERNIGHT.
* ANOTHER ROUND OF TSRA/SHRA EXPECTED TOMORROW AFTN.
JEE
//DISCUSSION...UPDATED 18Z...
THE ACTIVE PERIOD CONTINUES BUT THERE IS VERY HIGH UNCERTAINTY
REGARDING WHERE AND WHEN CONVECTION WILL OCCUR TODAY. TEMPS HAVE
CLIMBED INTO THE 70S WITH DEWPOINTS IN THE 60S WHICH SUGGESTS
FAVORABLE CONDITIONS. A LOW PRESSURE SYSTEM IS OVER SOUTH DAKOTA
AND A LEFT OVER CONVECTIVE SYSTEM IS OVER NE MO/SE IA/W IL. SHOWERS
ARE SLOWLY MOVING NORTHEAST WITH A FEW CONVECTIVE CELLS FORMING OVER
FORD COUNTY IL IN THE LAST FEW MINUTES. EXPECTING THUNDERSTORMS TO
DEVELOP ACROSS NORTH CENTRAL IL AND PUSH EAST THROUGH THE EASTERN
TERMINALS. SINCE THE AXIS OF BEST INSTABILITY IS EAST OF RFD...KEPT
TS OUT OF RFD. THAT BEING SAID RFD MAY SEE A FEW STRAY SHOWERS OVER
THE NEXT FEW HOURS. GUSTY S WINDS ARE EXPECTED BUT MAY SEE A BRIEF
SHIFT TO SSE WINDS BEHIND THE THUNDERSTORMS.
EXPECTING A NARROW WINDOW OF TSRA OF ABOUT AN HOUR...FOLLOWED BY
SHOWERS. THE AREA WILL REMAIN UNSTABLE OVERNIGHT WITH SCATTERED
SHOWERS EXPECTED OVERNIGHT. ANOTHER ROUND OF TSRA AND SHOWERS IS
EXPECTED LATE SATURDAY AFTERNOON/EARLY AS THE LOW PRESSURE SYSTEM
PASSES TO THE NORTH AND ITS COLD FRONT APPROACHES FROM THE WEST.
STRONG S WINDS ARE ONCE AGAIN EXPECTED TOMORROW...BUT GUSTS WILL NOT
BE AS STRONG.
JEE
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH CONFIDENCE IN PRECIP AFFECTING THE AIRPORTS THIS AFTERNOON.
* LOW CONFIDENCE IN TIMING AND DURATION.
* LOW CONFIDENCE IN SHRA COVERAGE TONIGHT.
* MEDIUM CONFIDENCE IN TIMING OF SHRA/TSRA TOMORROW AFTERNOON.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
JEE
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...CHC OF SHRA DURING THE EVE. MVFR POSSIBLE.
SUNDAY...SLT CHC OF MORNING SHRA.
MONDAY...VFR LIKELY.
TUESDAY...CHC OF MORNING MVFR.
WEDNESDAY & THURSDAY...CHC OF TSRA.
MTF
&&
.MARINE...
230 AM CDT
ANOMALOUSLY DEEP LOW PRESSURE ACROSS THE DAKOTAS WILL CONTINUE
SOUTHERLY FLOW ACROSS THE LAKE. THE STABLE MARINE LAYER WILL KEEP
WINDS FROM BECOMING TOO GUSTY...ALTHOUGH NEARSHORE AREAS OF IL AND
IN WILL LIKELY BE CLOSE TO SMALL CRAFT CRITERION WINDS GIVEN THE
OFFSHORE COMPONENT. PERIODS OF STORMS ARE LIKELY ACROSS THE LAKE
THROUGH TONIGHT AND POSSIBLY INTO SATURDAY. THE SYSTEM WILL SWING
A COLD FRONT ACROSS THE LAKE LATE SATURDAY NIGHT ALLOWING FOR A
WIND SHIFT TO NORTHWEST. THESE WINDS WILL TURN NORTHERLY ON SUNDAY
AND GRADUALLY DIMINISH INTO MONDAY AS HIGH PRESSURE BUILDS OVER
THE LAKE. THIS HIGH WILL SLOWLY SHIFT EAST THROUGH MIDWEEK...BUT
CONTINUE TO STRENGTHEN SO THE RETURN FLOW INFLUENCE LOOKS TO BE
SLOW TO SPREAD ACROSS THE LAKE. THIS SHOULD OFFER A FAIRLY QUIET
MARINE PERIOD FROM SUN-THU.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 7 PM SATURDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 7
PM SATURDAY.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ868-LMZ870-
LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 PM SATURDAY.
SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 7 PM FRIDAY.
&&
$$
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
116 PM CDT FRI MAY 31 2013
.MESOSCALE DISCUSSION...
115 PM CDT
INITIAL LOOK AT THE ATMOSPHERE IN PREPARATION OF AFTERNOON/EVENING
CONVECTION. SUPPORT FOR WIDESPREAD SEVERE APPEARS TO BE LESS
PRONOUNCED THAN EARLIER SIGNALS HAD SUGGESTED. A MINIMA OF 0-6KM
BULK SHEAR EXISTS EARLY THIS AFTERNOON ACROSS NORTHCENTRAL/NORTHEAST
ILLINOIS STRETCHING INTO NORTHWEST INDIANA. ALONG THE WESTERN
PERIPHERY OF THIS MINIMA IS AN AXIS OF MUCH HIGHER SHEAR AROUND
70KTS IN IOWA...TO NEARLY 80KTS STRETCHING SOUTH INTO CENTRAL
MISSOURI. VISIBLE IMAGERY SHOWS CONSIDERABLE CLOUD
COVER...REMNANTS/BLOWOFF OF EARLIER CONVECTION TO THE
SOUTHWEST...LIFTING NORTHEAST ACROSS THE CWFA AT THIS TIME. THIS
WILL INHIBIT SFC CAPE FROM GETTING OUT OF CONTROL THROUGH EARLY
THIS AFTERNOON...AND TOGETHER WITH THE MARGINAL SHEAR WOULD TEND
TO LIMIT THE LOCAL POTENTIAL FOR ORGANIZED CONVECTION OVER THE
NEXT FEW HOURS.
MORNING CONVECTION IN MISSOURI CORRELATED TO AN AXIS OF LOW LEVEL
MOISTURE CONVERGENCE AND A WEAK TROUGH DEPICTED AT 850 MB. LATEST
FIELDS FROM THE RAP MODEL SHOW THIS TROUGH AND THE WESTERN FOCUS
FOR THIS MOISTURE CONVERGENCE EXPANDING OUT OF THE SAINT LOUIS
AREA ACROSS ILLINOIS AND WORKING INTO THE CHICAGO METRO AREA BY
LATE AFTERNOON...22Z TO 00Z...WHILE GRADUALLY BECOMING LESS
FOCUSED. HI-RES GUIDANCE IS SUGGESTING THAT AS THIS CONVECTION
BEGINS TO LIFT THROUGH SW IL...IT WILL EXPAND ALONG A LINE
STRETCHING FROM SAINT LOUIS THROUGH BLOOMINGTON TO KANKAKEE AND
TOWARD MICHIGAN CITY.
A SMALLER AREA OF LATE MORNING AND EARLY AFTERNOON ISOLATED
STORMS OVER IOWA ALSO IS NICELY CORRELATED TO AN AXIS OF MOISTURE
CONVERGENCE IN THE RAP...BUT WAS MUCH LESS PRONOUNCED AND
MIGRATING MORE TO THE NORTH RATHER THAN EAST INTO ILLINOIS. THIS
CONVECTION WAS CLOSER TO THE 500MB VORT MAX AND IN AN AREA OF
ANTICIPATED STEEPENING LAPSE RATES THROUGHOUT THE AFTN. AS THE
TROUGH AXIS SLOWLY SLIDES EAST...SOME OF THIS MAY PUSH INTO
NORTHWEST IL BUT MAY NOT HAVE THE LONGEVITY TO CONTINUE ACROSS
NORTHCENTRAL/NORTHEAST IL.
BEACHLER/LENNING
&&
.DISCUSSION...
328 AM...MAIN FORECAST CONCERN AND CHALLENGE REMAINS CONVECTIVE
TRENDS/TIMING THROUGH SATURDAY EVENING ALONG WITH POTENTIAL FOR
SEVERE WEATHER AND HEAVY RAIN/FLOODING.
WAVE OF SHOWERS WITH SOME EMBEDDED THUNDER WILL CONTINUE LIFTING
NORTHEAST AWAY FROM THE AREA EARLY THIS MORNING WITH SUBSIDENCE
INTO THE MID MORNING HOURS EXPECTED TO BRING SEVERAL HOURS OF DRY
WEATHER. ATTENTION THEN SHIFTS TO CONVECTION OVER NORTHEAST
KANSAS/NORTHWEST MISSOURI. MOST RECENT HRRR/RAP GUIDANCE SEEMS IN
BETTER AGREEMENT WITH 00Z SUITE OF MODELS SHOWING THIS ACTIVITY
SPREADING EAST/NORTHEAST AS THE MAIN SHORTWAVE LIFTS NORTHEAST...
THEN SUGGESTS RAPID DEVELOPMENT ACROSS WESTERN AND NORTH CENTRAL
IL THIS AFTERNOON...PERHAPS EARLY THIS AFTERNOON. HOWEVER...
THERE STILL REMAINS SOME UNCERTAINTY REGARDING WHERE CONVECTION
DEVELOPS AND WHETHER IT AFFECTS ALL OR PART OF THE CWA. CONFIDENCE
INCREASES ACROSS THE SOUTHERN HALF/TWO THIRDS OF THE AREA.
WITH THE EXPECTATION THAT THIS MORNING WILL END UP BEING MAINLY
DRY AND EVENTUALLY PARTLY/MOSTLY SUNNY...TEMPS REACHING LOWER 80S
SEEMS ON TRACK ALONG WITH DEWPOINTS REBOUNDING BACK INTO THE
MID/UPPER 60S. SUFFICIENT SHEAR AND STRONG LAPSE RATES COMBINED
WITH THE VERY MOIST/UNSTABLE LOW LEVELS WILL SUPPORT SEVERE
WEATHER ACROSS THE ENTIRE AREA WITH THE MAIN THREAT APPEARING TO
BE DAMAGING WINDS WITH ASSOCIATED LINES/BOWING SEGMENTS. THOUGH
LARGE HAIL WITH STRONGER CORES AND ISOLATED TORNADOES WILL REMAIN
POSSIBLE.
CONVECTION WILL THEN SHIFT EAST THIS EVENING/OVERNIGHT. AS THE
UPPER TROUGH MOVES CLOSER TO THE WESTERN LAKES SATURDAY...ANOTHER
WAVE IS EXPECTED TO LIFT NORTHEAST SATURDAY BUT LIKELY BE A LITTLE
FURTHER EAST WITH CONVECTION LIKELY AFFECTING MAINLY EASTERN IL
AND NORTHWEST INDIANA...PERHAPS ALONG/EAST OF THE I-55 OR I-57
CORRIDORS. SEVERE WEATHER WILL ONCE AGAIN BE POSSIBLE SATURDAY
AFTERNOON INTO SATURDAY EVENING.
NO CHANGES PLANNED TO THE FLASH FLOOD WATCH WHICH IS IN EFFECT FOR
THE ENTIRE AREA THROUGH SATURDAY EVENING. FORECAST STORM TOTAL
RAINFALL...FROM THIS MORNING THROUGH SATURDAY EVENING...RANGES
FROM ABOUT AN INCH NEAR THE WI/IL BORDER TO 2-2.5 INCHES FROM A
CHICAGO/PERU LINE SOUTH. SOME AREAS WILL LIKELY SEE LESS AND SOME
AREAS MAY SEE MORE. INDIVIDUAL STORM MOTION WILL PROBABLY BE FAST
ENOUGH THAT WHILE HEAVY/TORRENTIAL RAIN WILL FALL...ITS DURATION
COULD BE SHORT. BUT IF THE STORMS BEGIN TO TRAIN OVER THE SAME
AREAS...WITH RAINFALL RATES OF 1 TO 2+ INCHES/HOUR...ON ALREADY
SATURATED GROUND...THEN FLASH FLOODING MAY BE POSSIBLE.
AS THE UPPER TROUGH/SURFACE LOW FINALLY DEPART SUNDAY...ONE LAST
WAVE PIVOTING AROUND THE WESTERN LAKES COULD PRODUCE SOME SHOWERS
SUNDAY MORNING. BROAD BUT WEAK HIGH PRESSURE THEN BUILDS ACROSS
THE LAKES SUNDAY AFTERNOON THROUGH MONDAY WITH A SHOT OF COOLER
AIR. WHILE HIGHS ON SUNDAY ARE ONLY EXPECTED TO BE IN THE
60S...LOWER 70S SOUTH...WINDS WILL TURN OFF THE LAKE SUNDAY
AFTERNOON...THUS COOLER/FALLING TEMPS AT THE LAKE SUNDAY
AFTERNOON. LOWS THEN DROP INTO THE 40S IN MANY AREAS MONDAY
MORNING AND POSSIBLY TUESDAY MORNING AS WELL. SEVERAL DAYS OF
EASTERLY WINDS WILL KEEP THE LAKE SHORE AREAS COOLER NEXT WEEK.
PATTERN APPEARS TO TURN MORE ACTIVE AGAIN TUESDAY INTO WEDNESDAY
AS ANOTHER SLOW MOVING UPPER LOW TRACKS ACROSS THE PLAINS THOUGH
ITS STILL FAIRLY EARLY TO DETERMINE WHERE AND WHEN THIS LOW WILL
MOVE THOUGH HAVE INCLUDED CHANCE POPS INTO MID/LATE WEEK AS THIS
NEXT SYSTEM POTENTIALLY APPROACHES. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* S WINDS GUSTING TO ARND 25 KT THROUGH THE DAY.
* SHOWERS AND THUNDERSTORMS EXPECTED AGAIN THIS AFTN.
* BEST CHANCE FOR TSRA IS IN THE MID AFTN...WITH STRONG TO SEVERE
STORMS PSBL.
JEE
//DISCUSSION...UPDATED 12Z...
A BREAK IN CONVECTION WILL BE OVER THE AREA THROUGH THE REMAINDER
OF THE MORNING RUSH. LINGERING MVFR CIGS FROM LAST NIGHTS RAIN
HAVE MAINLY DISSIPATED AND/OR SHIFTED EAST...SO THE MAIN CONCERN
CENTERS ON TIMING THE STORM CHANCES. OUR CONVECTIVE POTENTIAL
LOOKS TO BEGIN FROM ONGOING STORMS IN MISSOURI...WHETHER IT BE
FROM THE COMPLEX ITSELF EVOLVING NORTHEAST OR SOME OFFSHOOT OF
IT. THE STRONGEST CONVECTION MAY END UP REMAINING SOUTH OF THE
TERMINALS...AT LEAST AT FIRST. BY MID-AFTERNOON...RE-ENHANCEMENT
OF STORMS BOTH IN COVERAGE AND IN MAGNITUDE IS EXPECTED
IMMEDIATELY AHEAD OF THE DECAYING SYSTEM AND ITS FORCING. WHETHER
THAT WILL BE FAR ENOUGH NORTH TO IMPACT ORD AND THE OTHER TAF
SITES WITH HEAVY CONVECTION IS TOO CHALLENGING TO TELL FOR SURE
YET...BUT IT DOES LOOK LIKE IT SHOULD BE AT LEAST CLOSE. SO HAVE
PRESERVED THE PREVAILING THUNDER AT THE MOST FAVORED TIME
WINDOWS...BUT ITS POSSIBLE IT HAPPENS BEFORE AND/OR AFTER THIS
DEPENDING ON NUMEROUS FACTORS. THIS IS ALWAYS A CHALLENGE WITH
ONGOING EARLY MORNING CONVECTION AND HOW IT ALTERS THE ATMOSPHERE.
SOUTHERLY WINDS ARE LIKELY TO BEGIN GUSTING BY MID-MORNING WITH
GUSTS TO NEAR 25 KT AT TIMES. STORM WINDS AND RAIN-COOLED OUTFLOW
COULD LEAD TO STRONGER WIND GUSTS AND VARIABILITY IN DIRECTION IF
THEY WERE TO PASS OVER THE AIRFIELDS.
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH CONFIDENCE IN SHRA/TSRA DVLPG.
* MEDIUM CONFIDENCE IN TIMING OF SHRA/TSRA.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
JEE
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...CHC OF SHRA DURING THE EVE. MVFR POSSIBLE.
SUNDAY...SLT CHC OF MORNING SHRA.
MONDAY...VFR LIKELY.
TUESDAY...CHC OF MORNING MVFR.
WEDNESDAY & THURSDAY...CHC OF TSRA.
MTF
&&
.MARINE...
230 AM CDT
ANOMALOUSLY DEEP LOW PRESSURE ACROSS THE DAKOTAS WILL CONTINUE
SOUTHERLY FLOW ACROSS THE LAKE. THE STABLE MARINE LAYER WILL KEEP
WINDS FROM BECOMING TOO GUSTY...ALTHOUGH NEARSHORE AREAS OF IL AND
IN WILL LIKELY BE CLOSE TO SMALL CRAFT CRITERION WINDS GIVEN THE
OFFSHORE COMPONENT. PERIODS OF STORMS ARE LIKELY ACROSS THE LAKE
THROUGH TONIGHT AND POSSIBLY INTO SATURDAY. THE SYSTEM WILL SWING
A COLD FRONT ACROSS THE LAKE LATE SATURDAY NIGHT ALLOWING FOR A
WIND SHIFT TO NORTHWEST. THESE WINDS WILL TURN NORTHERLY ON SUNDAY
AND GRADUALLY DIMINISH INTO MONDAY AS HIGH PRESSURE BUILDS OVER
THE LAKE. THIS HIGH WILL SLOWLY SHIFT EAST THROUGH MIDWEEK...BUT
CONTINUE TO STRENGTHEN SO THE RETURN FLOW INFLUENCE LOOKS TO BE
SLOW TO SPREAD ACROSS THE LAKE. THIS SHOULD OFFER A FAIRLY QUIET
MARINE PERIOD FROM SUN-THU.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 7 PM SATURDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 7
PM SATURDAY.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ868-LMZ870-
LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 PM SATURDAY.
SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 7 PM FRIDAY.
&&
$$
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
232 AM CDT FRI MAY 31 2013
.DISCUSSION...
504 PM CDT
HAVE DECIDED TO EXPAND THE CURRENT FLASH FLOOD WATCH...TO INCLUDE
THE ENTIRE CWA.
WAS ON THE FENCE EARLIER WITH REGARDS TO EXPANDING THE CURRENT
FLASH FLOOD WATCH FOR THE REMAINDER OF THE CWA...BUT WITH LATEST
TRENDS THIS PAST AFTERNOON...HAVE DECIDED TO INCLUDE THE ENTIRE
CWA. THE THUNDERSTORMS THIS PAST AFTERNOON HAVE BEEN VERY GOOD
RAIN PRODUCERS...WHICH WILL LIKELY CONTINUE OVER THE NEXT COUPLE
OF HOURS AS PWATS REMAIN RATHER HIGH. ALSO...MONITORING THE
CONVECTIVE LINE TO THE WEST AND ITS MOVEMENT EAST INTO THE CWA.
LATEST TRENDS AND SHORT TERM GUIDANCE ARE HINTING AT THE
POSSIBILITY OF MORE TRAINING ACROSS THE CWA...WITH CURRENT FLOW IN
PLACE...DEFINITELY SEEMS REASONABLE.
RODRIGUEZ
//PREV DISCUSSION...
400 PM CDT
MAIN FORECAST CONCERNS REMAIN TIED TO THE ACTIVE WEATHER PATTERN
EXPECTED THROUGH THE START OF THE WEEKEND...WITH ROUNDS OF HEAVY
RAINFALL LIKELY AS WELL AS CONTINUED CHANCES FOR SEVERE WEATHER.
HAVE NOT EXPANDED THE FFA WATCH AT THIS TIME WITH MORE WIDESPREAD
HEAVY RAINFALL AND FLOODING NOT APPEARING LIKELY UNTIL LATER
FRIDAY AFTERNOON INTO FRIDAY NIGHT. THIS IS NOT TO SAY THAT
LOCALIZED FLOODING COULD NOT OCCUR WITH ANY POSSIBLE STRONG
THUNDERSTORMS TONIGHT. A MORE LIKELY SCENARIO AT THIS TIME IS WITH
THE CURRENT SCATTERED DEVELOPMENT TO BE REPLACED WITH A MORE
PROGRESSIVE AREA OF THUNDERSTORMS.
CURRENT ISOLATED TO SCATTERED ACTIVITY ACROSS THE CWA WILL
CONTINUE TO INCREASE IN COVERAGE THIS EVENING...AS LARGE SCALE
FORCING INCREASES WITH THE APPROACH A FAIRLY STOUT MID LEVEL WAVE
PROPAGATING NORTH THROUGH CENTRAL ILLINOIS. AREAS WHICH CONTINUE
TO BE FAVORED ARE LOCATIONS ALONG AND WEST OF A LINE FROM CRYSTAL
LAKE SOUTH TO GIBSON CITY IN ILLINOIS. LATEST RAP ANALYSIS SHOWS
MODERATE INSTABILITY IN PLACE WITH MLCAPE AROUND 2000 J/KG...AND
WITH MID/LOW LEVEL LAPSE RATES EXPECTED TO ONLY INCREASE OVER THE
NEXT COUPLE OF HOURS. THIS INCREASING FORCING AND INSTABILITY WILL
AID FURTHER DEVELOPMENT/EXPANSION OF CURRENT ACTIVITY ONGOING
ACROSS THE WESTERN HALF OF THE CWA. DEEP LAYER SHEAR REMAINS
MEAGER AT 25-30KT PRIMARILY OVER THE WESTERN CWA WHILE 0-1KM SHEAR
ALSO REMAINS HIGHEST ALONG OR JUST WEST OF THE CWA...ESPECIALLY
GOING INTO WESTERN ILLINOIS AND EASTERN IOWA.
HOWEVER...SHORT TERM GUIDANCE CONTINUES TO SHOW AN INCREASE IN
BOTH DEEP LAYER SHEAR AND LOW LEVEL SHEAR ACROSS THE CURRENT WATCH
AREA THROUGH THE REMAINDER OF THE AFTERNOON. THIS WILL HELP FOR
MORE ORGANIZED AND LONGER LIVED DEVELOPMENT ACROSS THE WESTERN
CWA...LEAVING THE THREAT OF HAIL/DAMAGING WINDS AS WELL AS
POSSIBLE TORNADOES. ALTHOUGH MORE ORGANIZED DEVELOPMENT IS MORE
LIKELY FOR THE WESTERN HALF OF THE CWA...SHORT TERM GUIDANCE IS
HINTING AT A SLIGHT INCREASE IN DEEP LAYER SHEAR MORE TOWARDS FAR
NORTHEAST ILLINOIS. THIS SLIGHT INCREASE COINCIDING WITH THE
CURRENT CAPE IN PLACE...COULD FAVOR SOME ISOLATED STRONGER
DEVELOPMENT IN THAT LOCATION IN THE NEXT COUPLE OF HOURS. WILL
NEED CONTINUE TO MONITOR DEVELOPMENT IN THAT LOCATION...WHICH
WOULD INCLUDE THE CITY OF CHICAGO/METRO AREA LATE THIS AFTERNOON
INTO THE EARLY EVENING...AS I COULD EASILY FORESEE AN UPSCALE IN
GROWTH IN BOTH INTENSITY AND COVERAGE.
EVEN IF THAT DOES NOT MATERIALIZE THROUGH LATE THIS
AFTERNOON...CONTINUE TO MONITOR A LARGER LINE OF THUNDERSTORMS
SITUATED FROM SOUTHERN IOWA SOUTH INTO MISSOURI. THIS LINE IS TIED
MORE CLOSELY TO FAIRLY STRONG MID LEVEL WAVE LIFTING NORTHEAST OUT
KANSAS AND ATTENDANT SURFACE TROUGH/BOUNDARY FROM IOWA INTO
MISSOURI. ALL GUIDANCE IS SHOWING THIS LINE OF THUNDERSTORMS
WILL INCREASE IN INTENSITY OVER THE NEXT COUPLE OF HOURS...WHICH
WOULD MAKE SENSE AS THIS LINE OF THUNDERSTORMS MOVES FURTHER
EAST/NORTHEAST INTO A MORE UNSTABLE ENVIRONMENT. STRONG FORCING
OWING TO LARGE SCALE SUPPORT AND LOW/MID LEVEL CONVERGENCE SHOULD
AID IN THIS LINE OF THUNDERSTORMS FURTHER BLOSSOMING AS IT MOVES
TOWARDS THE WESTERN ILLINOIS...ESPECIALLY AS DEEP LAYER SHEAR IS
ALSO INCREASING.
THERE IS STILL SOME UNCERTAINTY AS TO THE WHOLE EVOLUTION OF THIS
LINE OF THUNDERSTORMS AS IT WORKS ITS WAY TOWARDS NORTHERN
ILLINOIS THIS EVENING...MAINLY IN THE STRENGTH OF THIS COMPLEX AND
POTENTIAL SEVERE THREAT. ALTHOUGH THERE WILL BE SOME SLIGHT
DIMINISHING TREND WITH THE CURRENT INSTABILITY IN PLACE...FEEL
THAT IT WILL MORE THAN SUFFICE TO HELP KEEP THIS LINE SHIFTING
EAST. ALSO...SHORT TERM GUIDANCE IS INDICATING THAT 0-3KM BULK
SHEAR WILL INCREASE TOWARDS THE 00Z TIME FRAME THIS
EVENING...WHICH WOULD ACT TO HELP FOR ORGANIZATION AND INCREASE IN
THREAT FOR LINEAR STRUCTURES/STRONG DAMAGING WINDS. SO HAVE
TRENDED MORE PESSIMISTIC...WITH THINKING THAT THIS LINE AND STRONG
DAMAGING WINDS COULD MOVE ACROSS NORTHERN ILLINOIS THIS EVENING.
HAVE ALSO TRENDED MORE TOWARDS THE HRRR...WITH SYSTEM TIMING
THINKING THAT IT SHOULD BE KNOCKING ON THE WESTERN CWA DOORSTEPS
BY 00-01Z AND THEN CONTINUE EAST TOWARDS NORTHEAST ILLINOIS
THROUGH THE SEVERAL HOURS THERE AFTER. BEYOND THAT TIME
FRAME...CONFIDENCE LOWERS WITH REGARDS TO THE STRENGTH OF THIS
SYSTEM. NONETHELESS...HEAVY RAINFALL AND FLASH FLOODING COULD
BECOME ISSUES OVERNIGHT TONIGHT ESPECIALLY AS PWATS ARE AT OR JUST
ABOVE 1.7 INCHES AND 850MB DEW POINTS REMAIN RATHER HIGH.
THUNDERSTORM COMPLEX IS THEN EXPECTED TO SHIFT EAST OF THE CWA BY
EARLY FRIDAY MORNING...WITH A DRYING TREND EXPECTED DURING THAT
TIME FRAME. THIS SHOULD NOT LAST TOO LONG WITH DRY CONDITIONS ONLY
EXPECTED THROUGH MID DAY AS ATTENTION QUICKLY SHIFTS BACK WEST
WITH THE APPROACH OF ANOTHER STRONG MID LEVEL WAVE EJECTING OUT OF
THE CENTRAL PLAINS. YET AGAIN...A SEVERE THREAT WILL BE IN PLACE
ON FRIDAY WITH GROWING CONCERNS OF MORE POTENTIAL FLOODING FROM
THIS POINT ON...INTO FRIDAY NIGHT AND SATURDAY. THE SEVERE THREAT
WILL LIKELY AFFECT THE ENTIRE CWA ON FRIDAY AND WITH CLEARING
ANTICIPATED FRIDAY MORNING...INSTABILITY IS EXPECTED TO RAPIDLY
INCREASE BY LATE MORNING WITH MODERATE TO STRONG INSTABILITY
LIKELY IN PLACE ACROSS THE CWA. STRONG DEEP LAYER SHEAR IN UPWARDS
OF 50-60KT WILL EASILY SUPPORT WIDESPREAD ORGANIZED DEVELOPMENT AS
SOON AS EARLY AFTERNOON ON FRIDAY. STRONG DAMAGING WINDS AND HAIL
ARE THE MAIN THREAT...BUT WITH SREF GUIDANCE INDICATING ELEMENTS
CORRESPONDING TO SUPERCELLULAR STRUCTURES OR ROTATING
THUNDERSTORMS COULD COME TOGETHER ACROSS THE CWA. WILL NEED TO
CONTINUE TO MONITOR THIS TIME FRAME AS WELL...AS WIDESPREAD SEVERE
IS APPEARING LIKELY ONCE AGAIN. GOING INTO FRIDAY NIGHT...HEAVY
RAINFALL APPEARS LIKELY WITH SEVERAL STRONG WAVES PROPAGATING
NORTHEAST ACROSS THE CWA PROVIDING CONTINUED DEVELOPMENT AS WELL
AS A STRONG LLJ ORIENTED TOWARDS NORTHEAST ILLINOIS...PUMPING HIGH
THETAE AIR INTO THE REGION.
RODRIGUEZ
EXTENDED PERIOD...SUNDAY THROUGH THURSDAY...
BY DAYBREAK SUNDAY THE UPPER RIDGE IS TO HAVE PROGRESSED EASTWARD
TO OVER THE UPPER MIDWEST AND MID MS VALLEY WITH A SURFACE
TROUGH/SECONDARY COLD FRONT JUST TO THE NORTHWEST AND NORTH OF THE
LOCAL FORECAST AREA. THIS TROUGH/FRONT IS PROGGED TO MOVE ACROSS ALL
OF THE FA DURING THE SUNDAY MORNING AS THE UPPER TROUGH CONTINUES ON
TO OVER THE UPPER GREAT LAKES AND LOWER OH VALLEY BY EVENING. UNTIL
THE TROUGH AXIS MOVES A BIT FURTHER EAST OF THE IMMEDIATE AREA THERE
WILL BE A LINGERING CHANCE OF SHOWERS DURING SUNDAY MORNING.
THE SECONDARY COLD FRONT WILL REINFORCE THE COLD AIR ADVECTION THAT
WILL HAVE STARTED TO OCCUR LATE SATURDAY AND SATURDAY NIGHT WITH THE
INITIAL COLD FRONT. BETWEEN THE PAIR OF FRONT 850HPA TEMPERATURES
ARE PROGGED TO FALL AROUND 10 DEGREES C FROM 18Z SATURDAY TO 00Z
MONDAY......DOWN TO AROUND +4 OR +5C. WITH COOL HIGH PRESSURE
BUILDING OVER THE AREA TEMPERATURES WILL BE COOL SUNDAY AND MONDAY
WITH HIGHS ONLY IN THE 60S...WITH LAKESIDE MAX TEMPERATURES LIKELY
TO ONLY BE IN THE 55-60F RANGE AS A LONG FETCH DOWN LAKE MICHIGAN
BRINGS AIR ADDITIONALLY COOLED BY THE STILL CHILLY LAKE ASHORE
SUNDAY. WHILE THE SURFACE RIDGE AXIS WILL BE MOVING OVER WI AND
WESTERN IL DURING MONDAY ALLOWING WINDS TO SLACKEN...A WEAK NE
SYNOPTIC FLOW WILL STILL BE IN PLACE AIDED BY A LAKE BREEZE.
THE FURTHER EASTWARD PROGRESS OF THE UPPER TROUGH IS TO BE SLOW AS A
CLOSED LOW TO FORM OVER SOUTHERN HUDSON BAY/NORTHERN ONTARIO IS
PROGGED TO BE DROP SOUTH...THEN SOUTHEAST AND EAST OVER ONTARIO
SATURDAY NIGHT THROUGH MONDAY NIGHT. AS THE UPPER TROUGH/LOW MOVES
FURTHER EAST A WEAK UPPER RIDGE WILL MOVE OVER THE REGION TUESDAY AS
ANOTHER UPPER LOW MOVES EAST OVER THE FAR SOUTHERN CANADIAN
PRAIRIE/FAR NORTHERN PLAINS. THIS WILL ALLOW A BIT OF MODERATION IN
TEMPERATURES TUESDAY AND WEDNESDAY AS EAST-SOUTHEAST WINDS BECOMES
SOUTHEASTERLY AND INCREASING THOUGH THIS LOW LEVEL FLOW WILL KEEP
THE IL SHORE...ESPECIALLY THE FAR NORTHERN PART....STILL CHILLY.
INLAND AREAS SHOULD PEAK IN THE UPPER 60S AND LOWER 70S TUESDAY...
AND A COUPLE DEGREES WARMER WEDNESDAY. WITH CONTINUED WARM AIR
ADVECTION AHEAD OF THE APPROACHING UPPER LOW/TROUGH THE WARMING
TREND WILL CONTINUE THURSDAY WITH MOST LOCATIONS REACHING THE MID
AND UPPER 70S THOUGH THERE WILL STILL BE AN EASTERLY COMPONENT TO
THE LOW LEVEL FLOW TO KEEP THE IL SHORELINE IN THE 60S.
TRS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* SHRA CONTINUING THROUGH 08Z-10Z WITH ONLY A SMALL CHANCE OF
THUNDER IN THAT TIME.
* SOME SHIFTING IN THE WINDS FROM SE TO SW THROUGH 12Z OR SO BUT
GUSTINESS SHOULD ONLY BE SPORADIC.
* MVFR FOG POSSIBLE AROUND DAYBREAK.
* SOUTHERLY WINDS GUSTING TO AROUND 25 KT DURING THE DAY TODAY.
* STORM CHANCES...INCLUDING STRONG POTENTIAL...RETURNING FRI
AFTERNOON AND EVE.
//DISCUSSION...UPDATED 06Z...
PERIODS OF MAINLY SHOWERS...WITH SOME STORMS /ESPECIALLY SOUTH AND
EAST TRACON AREAS/...WITH CONTINUE THROUGH 09Z-10Z. THERE IS
EXPECTED TO BE A LULL IN PRECIP COVERAGE DURING THE MORNING RUSH
BUT THERE STILL MAY BE A FEW SCATTERED SHOWERS. THE RAINS HAVE
FURTHER MADE THE LOW-LEVELS MOIST WHICH COULD HELP PATCHY FOG
DEVELOPMENT NEAR DAWN. SOUTHERLY WINDS WILL INCREASE AFTER
DAYBREAK AS MIXING ENSUES AND SOME STRONG GUSTS TO AROUND 25 KT
ARE EXPECTED AGAIN.
AS FOR THUNDER CHANCES THIS AFTERNOON AND EVE...IT IS CHALLENGING
AND QUITE A BIT IS LIKELY TO DEPEND ON HOW THUNDER ACTIVITY IN
EASTERN KS/MO PLAYS OUT EARLY THIS MORNING. IF THIS WORKS INTO IL
BY LATE MORNING/EARLY AFTERNOON IT MAY STIFLE SOME OF THE
EXPLOSIVE CONVECTIVE DEVELOPMENT THAT COULD OCCUR WITH AS MUCH
INSTABILITY AS WILL BE PRESENT. IT ALSO COULD KEEP MUCH OF THE
STORM ACTIVITY SOUTH OF THE CHICAGOLAND TERMINALS. THAT SAID...THE
CERTAINTY ON HOW THIS EARLY MORNING CONVECTION TO OUR WEST PLAYS
OUT IS LOW. WHILE THE SETUP FOR LATER TODAY INTO THIS EVE COULD
PRESENT SEVERAL HOURS
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE IN SHOWERS WITH MEDIUM CONFIDENCE IN NO THUNDER
OR IFR CONDITIONS IN RAIN.
* HIGH CONFIDENCE IN SOUTHERLY WINDS DURING THE DAY WITH MEDIUM
CONFIDENCE IN MAGNITUDE OF THE GUSTS.
* LOW CONFIDENCE ON TIMING AND DURATION OF AFTERNOON/EVE
THUNDERSTORMS.
//OUTLOOK FOR ORD/MDW FOR 12Z SATURDAY-12Z THURSDAY...UPDATED 06Z...
* SATURDAY...TSRA LIKELY DURING THE DAY WITH A CHANCE OF SHRA
DURING THE NIGHT. MVFR CIGS/VIS POSSIBLE.
* SUNDAY...CHANCE OF SHRA EARLY...OTRW...VFR.
* MONDAY THROUGH EARLY TUESDAY...VFR. WX NIL.
* LATE TUESDAY THROUGH WEDNESDAY...CHANCE TSRA/SHRA.
MTF
&&
.MARINE...
230 AM CDT
ANOMALOUSLY DEEP LOW PRESSURE ACROSS THE DAKOTAS WILL CONTINUE
SOUTHERLY FLOW ACROSS THE LAKE. THE STABLE MARINE LAYER WILL KEEP
WINDS FROM BECOMING TOO GUSTY...ALTHOUGH NEARSHORE AREAS OF IL AND
IN WILL LIKELY BE CLOSE TO SMALL CRAFT CRITERION WINDS GIVEN THE
OFFSHORE COMPONENT. PERIODS OF STORMS ARE LIKELY ACROSS THE LAKE
THROUGH TONIGHT AND POSSIBLY INTO SATURDAY. THE SYSTEM WILL SWING
A COLD FRONT ACROSS THE LAKE LATE SATURDAY NIGHT ALLOWING FOR A
WIND SHIFT TO NORTHWEST. THESE WINDS WILL TURN NORTHERLY ON SUNDAY
AND GRADUALLY DIMINISH INTO MONDAY AS HIGH PRESSURE BUILDS OVER
THE LAKE. THIS HIGH WILL SLOWLY SHIFT EAST THROUGH MIDWEEK...BUT
CONTINUE TO STRENGTHEN SO THE RETURN FLOW INFLUENCE LOOKS TO BE
SLOW TO SPREAD ACROSS THE LAKE. THIS SHOULD OFFER A FAIRLY QUIET
MARINE PERIOD FROM SUN-THU.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 7 PM SATURDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 7
PM SATURDAY.
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
100 AM CDT FRI MAY 31 2013
.DISCUSSION...
504 PM CDT
HAVE DECIDED TO EXPAND THE CURRENT FLASH FLOOD WATCH...TO INCLUDE
THE ENTIRE CWA.
WAS ON THE FENCE EARLIER WITH REGARDS TO EXPANDING THE CURRENT
FLASH FLOOD WATCH FOR THE REMAINDER OF THE CWA...BUT WITH LATEST
TRENDS THIS PAST AFTERNOON...HAVE DECIDED TO INCLUDE THE ENTIRE
CWA. THE THUNDERSTORMS THIS PAST AFTERNOON HAVE BEEN VERY GOOD
RAIN PRODUCERS...WHICH WILL LIKELY CONTINUE OVER THE NEXT COUPLE
OF HOURS AS PWATS REMAIN RATHER HIGH. ALSO...MONITORING THE
CONVECTIVE LINE TO THE WEST AND ITS MOVEMENT EAST INTO THE CWA.
LATEST TRENDS AND SHORT TERM GUIDANCE ARE HINTING AT THE
POSSIBILITY OF MORE TRAINING ACROSS THE CWA...WITH CURRENT FLOW IN
PLACE...DEFINITELY SEEMS REASONABLE.
RODRIGUEZ
//PREV DISCUSSION...
400 PM CDT
MAIN FORECAST CONCERNS REMAIN TIED TO THE ACTIVE WEATHER PATTERN
EXPECTED THROUGH THE START OF THE WEEKEND...WITH ROUNDS OF HEAVY
RAINFALL LIKELY AS WELL AS CONTINUED CHANCES FOR SEVERE WEATHER.
HAVE NOT EXPANDED THE FFA WATCH AT THIS TIME WITH MORE WIDESPREAD
HEAVY RAINFALL AND FLOODING NOT APPEARING LIKELY UNTIL LATER
FRIDAY AFTERNOON INTO FRIDAY NIGHT. THIS IS NOT TO SAY THAT
LOCALIZED FLOODING COULD NOT OCCUR WITH ANY POSSIBLE STRONG
THUNDERSTORMS TONIGHT. A MORE LIKELY SCENARIO AT THIS TIME IS WITH
THE CURRENT SCATTERED DEVELOPMENT TO BE REPLACED WITH A MORE
PROGRESSIVE AREA OF THUNDERSTORMS.
CURRENT ISOLATED TO SCATTERED ACTIVITY ACROSS THE CWA WILL
CONTINUE TO INCREASE IN COVERAGE THIS EVENING...AS LARGE SCALE
FORCING INCREASES WITH THE APPROACH A FAIRLY STOUT MID LEVEL WAVE
PROPAGATING NORTH THROUGH CENTRAL ILLINOIS. AREAS WHICH CONTINUE
TO BE FAVORED ARE LOCATIONS ALONG AND WEST OF A LINE FROM CRYSTAL
LAKE SOUTH TO GIBSON CITY IN ILLINOIS. LATEST RAP ANALYSIS SHOWS
MODERATE INSTABILITY IN PLACE WITH MLCAPE AROUND 2000 J/KG...AND
WITH MID/LOW LEVEL LAPSE RATES EXPECTED TO ONLY INCREASE OVER THE
NEXT COUPLE OF HOURS. THIS INCREASING FORCING AND INSTABILITY WILL
AID FURTHER DEVELOPMENT/EXPANSION OF CURRENT ACTIVITY ONGOING
ACROSS THE WESTERN HALF OF THE CWA. DEEP LAYER SHEAR REMAINS
MEAGER AT 25-30KT PRIMARILY OVER THE WESTERN CWA WHILE 0-1KM SHEAR
ALSO REMAINS HIGHEST ALONG OR JUST WEST OF THE CWA...ESPECIALLY
GOING INTO WESTERN ILLINOIS AND EASTERN IOWA.
HOWEVER...SHORT TERM GUIDANCE CONTINUES TO SHOW AN INCREASE IN
BOTH DEEP LAYER SHEAR AND LOW LEVEL SHEAR ACROSS THE CURRENT WATCH
AREA THROUGH THE REMAINDER OF THE AFTERNOON. THIS WILL HELP FOR
MORE ORGANIZED AND LONGER LIVED DEVELOPMENT ACROSS THE WESTERN
CWA...LEAVING THE THREAT OF HAIL/DAMAGING WINDS AS WELL AS
POSSIBLE TORNADOES. ALTHOUGH MORE ORGANIZED DEVELOPMENT IS MORE
LIKELY FOR THE WESTERN HALF OF THE CWA...SHORT TERM GUIDANCE IS
HINTING AT A SLIGHT INCREASE IN DEEP LAYER SHEAR MORE TOWARDS FAR
NORTHEAST ILLINOIS. THIS SLIGHT INCREASE COINCIDING WITH THE
CURRENT CAPE IN PLACE...COULD FAVOR SOME ISOLATED STRONGER
DEVELOPMENT IN THAT LOCATION IN THE NEXT COUPLE OF HOURS. WILL
NEED CONTINUE TO MONITOR DEVELOPMENT IN THAT LOCATION...WHICH
WOULD INCLUDE THE CITY OF CHICAGO/METRO AREA LATE THIS AFTERNOON
INTO THE EARLY EVENING...AS I COULD EASILY FORESEE AN UPSCALE IN
GROWTH IN BOTH INTENSITY AND COVERAGE.
EVEN IF THAT DOES NOT MATERIALIZE THROUGH LATE THIS
AFTERNOON...CONTINUE TO MONITOR A LARGER LINE OF THUNDERSTORMS
SITUATED FROM SOUTHERN IOWA SOUTH INTO MISSOURI. THIS LINE IS TIED
MORE CLOSELY TO FAIRLY STRONG MID LEVEL WAVE LIFTING NORTHEAST OUT
KANSAS AND ATTENDANT SURFACE TROUGH/BOUNDARY FROM IOWA INTO
MISSOURI. ALL GUIDANCE IS SHOWING THIS LINE OF THUNDERSTORMS
WILL INCREASE IN INTENSITY OVER THE NEXT COUPLE OF HOURS...WHICH
WOULD MAKE SENSE AS THIS LINE OF THUNDERSTORMS MOVES FURTHER
EAST/NORTHEAST INTO A MORE UNSTABLE ENVIRONMENT. STRONG FORCING
OWING TO LARGE SCALE SUPPORT AND LOW/MID LEVEL CONVERGENCE SHOULD
AID IN THIS LINE OF THUNDERSTORMS FURTHER BLOSSOMING AS IT MOVES
TOWARDS THE WESTERN ILLINOIS...ESPECIALLY AS DEEP LAYER SHEAR IS
ALSO INCREASING.
THERE IS STILL SOME UNCERTAINTY AS TO THE WHOLE EVOLUTION OF THIS
LINE OF THUNDERSTORMS AS IT WORKS ITS WAY TOWARDS NORTHERN
ILLINOIS THIS EVENING...MAINLY IN THE STRENGTH OF THIS COMPLEX AND
POTENTIAL SEVERE THREAT. ALTHOUGH THERE WILL BE SOME SLIGHT
DIMINISHING TREND WITH THE CURRENT INSTABILITY IN PLACE...FEEL
THAT IT WILL MORE THAN SUFFICE TO HELP KEEP THIS LINE SHIFTING
EAST. ALSO...SHORT TERM GUIDANCE IS INDICATING THAT 0-3KM BULK
SHEAR WILL INCREASE TOWARDS THE 00Z TIME FRAME THIS
EVENING...WHICH WOULD ACT TO HELP FOR ORGANIZATION AND INCREASE IN
THREAT FOR LINEAR STRUCTURES/STRONG DAMAGING WINDS. SO HAVE
TRENDED MORE PESSIMISTIC...WITH THINKING THAT THIS LINE AND STRONG
DAMAGING WINDS COULD MOVE ACROSS NORTHERN ILLINOIS THIS EVENING.
HAVE ALSO TRENDED MORE TOWARDS THE HRRR...WITH SYSTEM TIMING
THINKING THAT IT SHOULD BE KNOCKING ON THE WESTERN CWA DOORSTEPS
BY 00-01Z AND THEN CONTINUE EAST TOWARDS NORTHEAST ILLINOIS
THROUGH THE SEVERAL HOURS THERE AFTER. BEYOND THAT TIME
FRAME...CONFIDENCE LOWERS WITH REGARDS TO THE STRENGTH OF THIS
SYSTEM. NONETHELESS...HEAVY RAINFALL AND FLASH FLOODING COULD
BECOME ISSUES OVERNIGHT TONIGHT ESPECIALLY AS PWATS ARE AT OR JUST
ABOVE 1.7 INCHES AND 850MB DEW POINTS REMAIN RATHER HIGH.
THUNDERSTORM COMPLEX IS THEN EXPECTED TO SHIFT EAST OF THE CWA BY
EARLY FRIDAY MORNING...WITH A DRYING TREND EXPECTED DURING THAT
TIME FRAME. THIS SHOULD NOT LAST TOO LONG WITH DRY CONDITIONS ONLY
EXPECTED THROUGH MID DAY AS ATTENTION QUICKLY SHIFTS BACK WEST
WITH THE APPROACH OF ANOTHER STRONG MID LEVEL WAVE EJECTING OUT OF
THE CENTRAL PLAINS. YET AGAIN...A SEVERE THREAT WILL BE IN PLACE
ON FRIDAY WITH GROWING CONCERNS OF MORE POTENTIAL FLOODING FROM
THIS POINT ON...INTO FRIDAY NIGHT AND SATURDAY. THE SEVERE THREAT
WILL LIKELY AFFECT THE ENTIRE CWA ON FRIDAY AND WITH CLEARING
ANTICIPATED FRIDAY MORNING...INSTABILITY IS EXPECTED TO RAPIDLY
INCREASE BY LATE MORNING WITH MODERATE TO STRONG INSTABILITY
LIKELY IN PLACE ACROSS THE CWA. STRONG DEEP LAYER SHEAR IN UPWARDS
OF 50-60KT WILL EASILY SUPPORT WIDESPREAD ORGANIZED DEVELOPMENT AS
SOON AS EARLY AFTERNOON ON FRIDAY. STRONG DAMAGING WINDS AND HAIL
ARE THE MAIN THREAT...BUT WITH SREF GUIDANCE INDICATING ELEMENTS
CORRESPONDING TO SUPERCELLULAR STRUCTURES OR ROTATING
THUNDERSTORMS COULD COME TOGETHER ACROSS THE CWA. WILL NEED TO
CONTINUE TO MONITOR THIS TIME FRAME AS WELL...AS WIDESPREAD SEVERE
IS APPEARING LIKELY ONCE AGAIN. GOING INTO FRIDAY NIGHT...HEAVY
RAINFALL APPEARS LIKELY WITH SEVERAL STRONG WAVES PROPAGATING
NORTHEAST ACROSS THE CWA PROVIDING CONTINUED DEVELOPMENT AS WELL
AS A STRONG LLJ ORIENTED TOWARDS NORTHEAST ILLINOIS...PUMPING HIGH
THETAE AIR INTO THE REGION.
RODRIGUEZ
EXTENDED PERIOD...SUNDAY THROUGH THURSDAY...
BY DAYBREAK SUNDAY THE UPPER RIDGE IS TO HAVE PROGRESSED EASTWARD
TO OVER THE UPPER MIDWEST AND MID MS VALLEY WITH A SURFACE
TROUGH/SECONDARY COLD FRONT JUST TO THE NORTHWEST AND NORTH OF THE
LOCAL FORECAST AREA. THIS TROUGH/FRONT IS PROGGED TO MOVE ACROSS ALL
OF THE FA DURING THE SUNDAY MORNING AS THE UPPER TROUGH CONTINUES ON
TO OVER THE UPPER GREAT LAKES AND LOWER OH VALLEY BY EVENING. UNTIL
THE TROUGH AXIS MOVES A BIT FURTHER EAST OF THE IMMEDIATE AREA THERE
WILL BE A LINGERING CHANCE OF SHOWERS DURING SUNDAY MORNING.
THE SECONDARY COLD FRONT WILL REINFORCE THE COLD AIR ADVECTION THAT
WILL HAVE STARTED TO OCCUR LATE SATURDAY AND SATURDAY NIGHT WITH THE
INITIAL COLD FRONT. BETWEEN THE PAIR OF FRONT 850HPA TEMPERATURES
ARE PROGGED TO FALL AROUND 10 DEGREES C FROM 18Z SATURDAY TO 00Z
MONDAY......DOWN TO AROUND +4 OR +5C. WITH COOL HIGH PRESSURE
BUILDING OVER THE AREA TEMPERATURES WILL BE COOL SUNDAY AND MONDAY
WITH HIGHS ONLY IN THE 60S...WITH LAKESIDE MAX TEMPERATURES LIKELY
TO ONLY BE IN THE 55-60F RANGE AS A LONG FETCH DOWN LAKE MICHIGAN
BRINGS AIR ADDITIONALLY COOLED BY THE STILL CHILLY LAKE ASHORE
SUNDAY. WHILE THE SURFACE RIDGE AXIS WILL BE MOVING OVER WI AND
WESTERN IL DURING MONDAY ALLOWING WINDS TO SLACKEN...A WEAK NE
SYNOPTIC FLOW WILL STILL BE IN PLACE AIDED BY A LAKE BREEZE.
THE FURTHER EASTWARD PROGRESS OF THE UPPER TROUGH IS TO BE SLOW AS A
CLOSED LOW TO FORM OVER SOUTHERN HUDSON BAY/NORTHERN ONTARIO IS
PROGGED TO BE DROP SOUTH...THEN SOUTHEAST AND EAST OVER ONTARIO
SATURDAY NIGHT THROUGH MONDAY NIGHT. AS THE UPPER TROUGH/LOW MOVES
FURTHER EAST A WEAK UPPER RIDGE WILL MOVE OVER THE REGION TUESDAY AS
ANOTHER UPPER LOW MOVES EAST OVER THE FAR SOUTHERN CANADIAN
PRAIRIE/FAR NORTHERN PLAINS. THIS WILL ALLOW A BIT OF MODERATION IN
TEMPERATURES TUESDAY AND WEDNESDAY AS EAST-SOUTHEAST WINDS BECOMES
SOUTHEASTERLY AND INCREASING THOUGH THIS LOW LEVEL FLOW WILL KEEP
THE IL SHORE...ESPECIALLY THE FAR NORTHERN PART....STILL CHILLY.
INLAND AREAS SHOULD PEAK IN THE UPPER 60S AND LOWER 70S TUESDAY...
AND A COUPLE DEGREES WARMER WEDNESDAY. WITH CONTINUED WARM AIR
ADVECTION AHEAD OF THE APPROACHING UPPER LOW/TROUGH THE WARMING
TREND WILL CONTINUE THURSDAY WITH MOST LOCATIONS REACHING THE MID
AND UPPER 70S THOUGH THERE WILL STILL BE AN EASTERLY COMPONENT TO
THE LOW LEVEL FLOW TO KEEP THE IL SHORELINE IN THE 60S.
TRS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* SHRA CONTINUING THROUGH 08Z-10Z WITH ONLY A SMALL CHANCE OF
THUNDER IN THAT TIME.
* SOME SHIFTING IN THE WINDS FROM SE TO SW THROUGH 12Z OR SO BUT
GUSTINESS SHOULD ONLY BE SPORADIC.
* MVFR FOG POSSIBLE AROUND DAYBREAK.
* SOUTHERLY WINDS GUSTING TO AROUND 25 KT DURING THE DAY TODAY.
* STORM CHANCES...INCLUDING STRONG POTENTIAL...RETURNING FRI
AFTERNOON AND EVE.
//DISCUSSION...UPDATED 06Z...
PERIODS OF MAINLY SHOWERS...WITH SOME STORMS /ESPECIALLY SOUTH AND
EAST TRACON AREAS/...WITH CONTINUE THROUGH 09Z-10Z. THERE IS
EXPECTED TO BE A LULL IN PRECIP COVERAGE DURING THE MORNING RUSH
BUT THERE STILL MAY BE A FEW SCATTERED SHOWERS. THE RAINS HAVE
FURTHER MADE THE LOW-LEVELS MOIST WHICH COULD HELP PATCHY FOG
DEVELOPMENT NEAR DAWN. SOUTHERLY WINDS WILL INCREASE AFTER
DAYBREAK AS MIXING ENSUES AND SOME STRONG GUSTS TO AROUND 25 KT
ARE EXPECTED AGAIN.
AS FOR THUNDER CHANCES THIS AFTERNOON AND EVE...IT IS CHALLENGING
AND QUITE A BIT IS LIKELY TO DEPEND ON HOW THUNDER ACTIVITY IN
EASTERN KS/MO PLAYS OUT EARLY THIS MORNING. IF THIS WORKS INTO IL
BY LATE MORNING/EARLY AFTERNOON IT MAY STIFLE SOME OF THE
EXPLOSIVE CONVECTIVE DEVELOPMENT THAT COULD OCCUR WITH AS MUCH
INSTABILITY AS WILL BE PRESENT. IT ALSO COULD KEEP MUCH OF THE
STORM ACTIVITY SOUTH OF THE CHICAGOLAND TERMINALS. THAT SAID...THE
CERTAINTY ON HOW THIS EARLY MORNING CONVECTION TO OUR WEST PLAYS
OUT IS LOW. WHILE THE SETUP FOR LATER TODAY INTO THIS EVE COULD
PRESENT SEVERAL HOURS
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE IN SHOWERS WITH MEDIUM CONFIDENCE IN NO THUNDER
OR IFR CONDITIONS IN RAIN.
* HIGH CONFIDENCE IN SOUTHERLY WINDS DURING THE DAY WITH MEDIUM
CONFIDENCE IN MAGNITUDE OF THE GUSTS.
* LOW CONFIDENCE ON TIMING AND DURATION OF AFTERNOON/EVE
THUNDERSTORMS.
//OUTLOOK FOR ORD/MDW FOR 12Z SATURDAY-12Z THURSDAY...UPDATED 06Z...
* SATURDAY...TSRA LIKELY DURING THE DAY WITH A CHANCE OF SHRA
DURING THE NIGHT. MVFR CIGS/VIS POSSIBLE.
* SUNDAY...CHANCE OF SHRA EARLY...OTRW...VFR.
* MONDAY THROUGH EARLY TUESDAY...VFR. WX NIL.
* LATE TUESDAY THROUGH WEDNESDAY...CHANCE TSRA/SHRA.
MTF
&&
.MARINE...
1259 PM CDT
THE SHORT TERM OF THE MARINE FORECAST HAS A SMALL CRAFT ADVISORY FOR
STRONG WINDS ACROSS THE ILLINOIS AND NORTHWEST INDIANA NEARSHORE
WATERS.
ACROSS THE OPEN WATERS OF THE LAKE...MAINLY THE NORTHERN THIRD OF
THE LAKE...AREAS OF DENSE FOG CONTINUE.
VERY WARM/MOIST AIR CONTINUES TO SLIDE NORTH ACROSS THE LAKE...AND
WITH THE MUCH COOLER LAKE SURFACE WATER...HAS RESULTED IN AREAS OF
DENSE FOG PERSISTING. IT DOES APPEAR BASED ON LATEST VISIBLE IMAGERY
THAT THE FOG HAS REMAINED FOCUSED ACROSS THE NORTHERN THIRD OF THE
LAKE. OBS HAVE CONTINUED TO SHOW INCREASING GUSTS...WITH SPEEDS
GENERALLY AROUND 20-25KT ACROSS THE SOUTHERN HALF OF THE LAKE.
FURTHER NORTH IT APPEARS THE WINDS ARE SLIGHTLY LESS...WITH SPEEDS
GENERALLY IN THE 15-25KT.
THE TROUGH OF LOW PRESSURE REMAINS CENTERED ACROSS THE CENTRAL
PLAINS...WITH A WEAK LOW PRESSURE LIFTING NORTH INTO THE NORTHERN
PLAINS. AN ASSOCIATED WARM FRONT EXTENDS EAST THROUGH THE UPPER
GREAT LAKES REGION. WITH THE POSITION OF THE LOW PRESSURE AND THE
PERSISTING RIDGE OF HIGH PRESSURE ACROSS THE SOUTHEASTERN UNITED
STATES...THE WIND FLOW WILL REMAIN SOUTHERLY ACROSS THE LAKE. AT
TIMES THROUGH EARLY THIS EVENING GUSTS MAY APPROACH 30 KT...MAINLY
FOR THE SOUTHERN PORTIONS OF THE LAKE INCLUDING THE NEARSHORE
WATERS. AS A RESULT WILL MAINTAIN THE CURRENT SMALL CRAFT ADVISORY
THAT IS IN EFFECT.
THE TROUGH OF LOW PRESSURE POSITIONED OVER THE CENTRAL PLAINS WILL
SLOWLY PUSH EAST...WITH A LOW PRESSURE APPROACHING THE WESTERN GREAT
LAKES SAT MIDDAY. THE RECENT FORECAST TRENDS HAVE BEEN TO SLOW THE
ARRIVAL OF THIS SYSTEM...THUS IT IS POSSIBLE THAT THE MAIN LOW
PRESSURE MAY NOT ARRIVE UNTIL CLOSER TO SAT NIGHT. THEN AN
ASSOCIATED COLD FRONT WILL WILL PUSH EAST ACROSS THE LAKE OVERNIGHT
SAT INTO SUN. WINDS AT THAT POINT WILL TURN WESTERLY THEN NORTHERLY
WITH MUCH COOLER AIR FLOWING OVER THE LAKE.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 7 PM SATURDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 7
PM SATURDAY.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565
UNTIL 7 AM FRIDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
705 PM EDT FRI MAY 31 2013
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW
&&
.SYNOPSIS...
ISSUED AT 353 PM EDT FRI MAY 31 2013
SEVERAL ROUNDS OF SHOWERS AND THUNDERSTORMS WILL IMPACT CENTRAL
INDIANA AS A SLOW MOVING COLD FRONT APPROACHES. THE FRONT WILL MOVE
THROUGH THE REGION SATURDAY NIGHT WITH COOLER AND MUCH DRIER AIR
SPREADING IN WITH HIGH PRESSURE FOR THE FIRST HALF OF THE WORK WEEK.
CHANCES FOR THUNDERSTORMS WILL RETURN THURSDAY AND FRIDAY AS A COLD
FRONT MOVES INTO THE REGION.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 353 PM EDT FRI MAY 31 2013
BULK OF THE RAINFALL FROM EARLIER COMPLEX HAS SHIFTED EAST AND
INTENSIFIED AS IT HAS MOVED INTO A MORE UNSTABLE AIRMASS ACROSS
NORTHEAST KENTUCKY AND WESTERN OHIO. MUCH OF THE FORECAST AREA
REMAINS SHROUDED IN A RELATIVELY THICK VEIL OF CLOUD COVER WITH SOME
BREAKS HAVING DEVELOPED OVER THE WABASH VALLEY. THIS HAS
SIGNIFICANTLY IMPEDED TEMP RISES SO FAR...ALTHOUGH MUCH OF THE
FORECAST AREA HAS MADE IT INTO THE 70S AS OF 19Z.
DIFFICULT FORECAST FOR TONIGHT WITH CONCERNS GROWING FOR HEAVY RAIN
AND FLOODING AND POTENTIALLY A DECREASING THREAT FOR SEVERE WEATHER.
LITTLE IN THE WAY OF INSTABILITY ACROSS THE FORECAST AREA AS THE
CLOUDS AND RAIN HAVE REALLY WORKED OVER THE AIRMASS. AS
MENTIONED...DO EXPECT SOME THINNING OF THE CANOPY OVER THE NEXT FEW
HOURS WHICH SHOULD ALLOW FOR SOME DESTABILIZATION TO TAKE PLACE.
HOWEVER...PRESENCE OF WEAKENING MCV OVER CENTRAL ILLINOIS IS LIKELY
TO MAINTAIN A FAIR AMOUNT OF CLOUD COVER RIGHT INTO THE EVENING AND
SHOULD KEEP CONVECTION SCATTERED THROUGH 00Z.
EXPECT ROBUST CONVECTIVE DEVELOPMENT OVER THE OZARKS BACK INTO
OKLAHOMA AS THE AFTERNOON WEARS ON...WITH ADDITIONAL DEVELOPMENT
LIKELY EXPANDING NORTHEAST INTO THE MISSISSIPPI VALLEY AND INTO
ILLINOIS AS INCREASED BL SHEAR AND FORCING ALOFT COURTESY OF AN
INTENSIFYING UPPER JET. NOCTURNAL LOW LEVEL JET WILL ONCE AGAIN
DEVELOP AND NOSE INTO THE REGION AFTER NIGHTFALL AND COMBINED WITH
THE BETTER UPPER LEVEL FORCING APPROACHING FROM THE WEST AND
WHATEVER INSTABILITY CAN BE GLEANED OVER THE NEXT SEVERAL
HOURS...ANTICIPATE CONVECTION TO THE WEST TO COALESCE INTO AN MCS
AND DROP SOUTHEAST INTO THE FORECAST AREA OVERNIGHT. LACK OF MORE
SUBSTANTIAL INSTABILITY HAS RAISED DOUBTS AS TO WHETHER STORMS WILL
BE SEVERE AS THEY ENTER THE FORECAST AREA. FEELING AT THIS POINT IS
THAT STORMS WILL BE STRONG WITH POTENTIALLY AN ISOLATED RISK FOR
DAMAGING WINDS. OTHERWISE...THE PRIMARY CONCERN WILL BE THE HEAVY
RAIN.
HEAVY RAIN AND FLOODING IS BECOMING A GREATER CONCERN...ESPECIALLY
ACROSS THE WABASH VALLEY WHICH EXPERIENCED 1 TO 2 INCHES OF RAIN
LAST NIGHT AND EARLY THIS MORNING. PRECIPITABLE WATER VALUES IN
EXCESS OF 1.75 INCHES ARE ANTICIPATED OVERNIGHT WITH A DEEP
SATURATED COLUMN EXTENDING UP TO NEAR 650MB. IN ADDITION...BROAD
SOUTHWEST FLOW ALOFT AND POTENTIAL FOR AN AXIS OF DEEP CONVERGENCE
UP TO ABOUT 700MB ALL SUPPORT POTENTIAL FOR TORRENTIAL RAINFALL AND
EFFICIENT RATES LATE TONIGHT. COULD SEE AMOUNTS IN EXCESS OF 1-2
INCHES OVER FAR WESTERN FORECAST AREA. WILL BE INTRODUCING A FLASH
FLOOD WATCH FOR THE WABASH VALLEY THROUGH 12Z SUNDAY BECAUSE OF
THESE CONCERNS. WILL RAISE POPS TO LIKELY OVER THE EAST AND
CATEGORICAL OVER THE WEST LATE TONIGHT.
TEMPS...MOS GUIDANCE LOOKS REASONABLE AS LOW TEMPS WILL ONLY FALL
INTO THE UPPER 60S TO NEAR 70 WITH SATURATED LOWER LEVELS.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
ISSUED AT 353 PM EDT FRI MAY 31 2013
FORECAST CHALLENGES REMAIN ON HEAVY RAIN AND SEVERE WEATHER
POTENTIAL THROUGH SATURDAY NIGHT AS THE COLD FRONT TRACKS SLOWLY
THROUGH THE REGION.
POTENTIAL FOR A SCENARIO SIMILAR TO THIS MORNING TO PLAY OUT
SATURDAY MORNING AS REGION MAY RESIDE UNDERNEATH A THICK CLOUD
CANOPY WITHIN A STABLE ENVIRONMENT IN WAKE OF OVERNIGHT CONVECTION.
THAT PRESENTS CHALLENGES ONCE AGAIN AS TO WHETHER ANY SUBSTANTIAL
HEATING CAN TAKE PLACE THROUGHOUT THE DAY AND ULTIMATELY HOW
UNSTABLE THE AIRMASS CAN GET BY AFTERNOON. THE UPPER LEVEL DYNAMICS
ARE ARGUABLY BETTER WITH CENTRAL INDIANA REMAINING IN THE RIGHT REAR
QUAD OF THE 100KT UPPER JET WITH UPPER DIFFLUENCE AHEAD OF THE WAVE
ALOFT ENHANCING CONVECTIVE DEVELOPMENT. ADDITIONALLY...LOW LEVEL JET
WILL PERSIST ACROSS THE REGION ALL DAY WITH PRECIP WATER VALUES
REMAINING ABOVE 1.50-1.75 IN. THE QUESTION MARK AGAIN IS WHETHER
INSTABILITY WILL BE HAMPERED BASED ON CLOUD COVER AND ADDITIONAL
CONVECTIVE DEVELOPMENT AS THE DAY PROGRESSES. WHILE ISOLATED
DAMAGING WINDS FROM STORMS CANNOT BE RULED OUT...CONFIDENCE REMAINS
LOW IN A LARGER SCALE SEVERE WEATHER EVENT SATURDAY AFTERNOON AND
EVENING BASED ON FACTORS MENTIONED ABOVE.
AT THIS POINT...CONCERN IS ONCE AGAIN GREATER TOWARDS HEAVY RAINFALL
WITH DEEP MOISTURE REMAINING AND THE PRESENCE OF THE LOW LEVEL JET
AND SUBSEQUENT CONVERGENCE THROUGH THE BOUNDARY LAYER. COULD EASILY
SEE REPEATED ROUNDS OF STORMS THROUGHOUT THE DAY OR POSSIBLY ANOTHER
MCS LATER IN THE AFTERNOON AND EVENING AS THE UPPER LEVEL SUPPORT
MOVES IN FROM THE WEST. THE POTENTIAL FOR ANOTHER 1-2 INCHES OF
RAINFALL IS POSSIBLE INTO SATURDAY EVENING. DEPENDING ON HOW THE
CONVECTIVE PATTERN EVOLVES TONIGHT AND INTO SATURDAY...THE FLASH
FLOOD WATCH MAY NEED TO BE EXPANDED FURTHER EAST ACROSS THE FORECAST
AREA.
MODEL GUIDANCE CONSISTENT IN BRINGING THE UPPER TROUGH AXIS AND COLD
FRONT ACROSS THE REGION LATE SATURDAY NIGHT WITH WIDESPREAD RAINFALL
SHIFTING EAST. HAVE HELD ONTO SLIGHT CHANCE POPS SUNDAY AS A WEAK
SHORTWAVE ALOFT MOVES ACROSS THE OHIO VALLEY AND INTERACTS WITH THE
COLD POOL IN WAKE OF THE FRONTAL PASSAGE. EXPECT JUST ISOLATED
SHOWERS AS MODEL SOUNDINGS SHOW LIMITED INSTABILITY. REMAINDER OF
THE SHORT TERM WILL BE QUIET AS A LARGE AREA OF HIGH PRESSURE BUILDS
IN WITH COOLER AND MUCH DRIER AIR.
TEMPS...WITH THE EXPECTATION OF CLOUD COVER AND WIDESPREAD PRECIP
COVERAGE ON SATURDAY...FELT MAVMOS GUIDANCE TOO WARM WITH TEMPS IN
THE MID 80S. UNDERCUT BY SEVERAL DEGREES AND KEEPING MUCH OF THE
FORECAST AREA IN THE 70S. COOLER AIR EXPANDS INTO THE REGION SUNDAY
AND MONDAY WITH TEMPS FALLING BACK INTO THE UPPER 60S/LOWER 70S BY
MONDAY. MOS LOOKED REASONABLE FOR OVERNIGHT LOWS. COULD SEE SOME
UPPER 40S IN RURAL LOCALES NORTH OF INDY METRO MONDAY MORNING.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
ISSUED AT 256 PM EDT FRI MAY 31 2013
FAIRLY QUIET START TO THE LONG TERM PERIOD WITH BROAD SURFACE HIGH
PRESSURE OVER THE AREA. AN UPPER LEVEL SYSTEM WILL PUSH ACROSS THE
NORTHERN PLAINS...AND MAY BRING SOME THUNDERSTORMS TO THE AREA
BEGINNING AS EARLY AS WEDNESDAY NIGHT...WITH CHANCES INCREASING
TOWARD THE END OF THE WEEK. ALLBLEND HANDLED THIS WELL AND
REQUIRED FEW TWEAKS.
INITIALIZED TEMPERATURES WERE FAIRLY CLOSE...AGAIN WITH ONLY A FEW
MINOR TWEAKS REQUIRED. SHOULD SEE A SLIGHT WARMING TREND THROUGH
THE WEEK...WITH TEMPERATURES IN THE 80S MAKING A RETURN TO THE
AREA LATE IN THE WEEK.
&&
.AVIATION /DISCUSSION FOR 010000Z TAF ISSUANCE/...
ISSUED AT 703 PM EDT FRI MAY 31 2013
SOME MVFR CLOUDS OVER THE SITES CURRENTLY BUT THESE SHOULD LESSEN
WITH SUNSET AND VFR SHOULD BE THE RULE FOR A COUPLE OF HOURS. A LINE
OF THUNDERSTORMS CURRENTLY OVER WESTERN ILLINOIS WILL MOVE INTO THE
AREA STARTING AROUND 3-4Z OR SO AT KLAF AND THEN OVERSPREAD THE
OTHER SITES WITHIN A FEW HOURS. HRRR SHOWS THESE STORMS HANGING
AROUND THE SITES FOR SEVERAL HOURS AND NOT REALLY MOVING OFF TO THE
EAST UNTIL AFTER 12Z SATURDAY. WITH GRIDDED FORECAST ALSO SHOWING
LIKELY OR GREAT THUNDER CHANCES WILL GO WITH PREVAILING THUNDER FROM
ARRIVAL THROUGH MORNING. AFTER THAT WILL INCLUDE A PROB30 WITH GRIDS
STILL SHOWING LIKELY OR GREATER THUNDER CHANCES BUT THE EXPECTATION
THAT THERE WILL BE SOME SORT OF LULL IN THE MORNING BEFORE
THUNDERSTORMS FIRE UP AGAIN IN THE AFTERNOON. THUS WITH VERY HIGH
POPS AND THOUGHT THAT THUNDER WILL REFIRE IN THE AFTERNOON BROUGHT
PREVAILING THUNDER BACK IN AFTER 18Z. FAIRLY UNCERTAIN ABOUT WIND
GUSTS THROUGH THE OVERNIGHT. THINK THEY WILL NOT BE CONSTANT BUT
SHOULD PICK BACK UP IN/AROUND THUNDERSTORMS SO WILL ALLOW THESE TO
BE PREVAILING FOR MUCH OF THE NIGHT AS WELL. MAY DROP OFF IN THE
MORNING BEFORE PICKING BACK UP WITH GUSTS OF 20-25 KTS OUT OF THE
SOUTHWEST AGAIN IN THE AFTERNOON.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH SUNDAY MORNING FOR INZ028-029-035-036-
043>045-051>053-060-061-067>069.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM....NIELD
AVIATION...CP
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AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
222 AM EDT FRI MAY 31 2013
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 300 PM EDT THU MAY 30 2013
THE MAIN FOCUS THIS PERIOD IS ON CONVECTIVE POTENTIAL/EVOLUTION.
SYNOPTICALLY...A CLOSED LOW WILL MEANDER SLOWLY EAST ACROSS THE
NORTHERN PLAINS WITH DEEP/MOIST CYCLONICALLY CURVED SOUTHWEST FLOW
IN PLACE FROM THE SOUTHERN PLAINS NORTHEAST INTO THE GREAT LAKES
REGION. AT THE SURFACE THE PRIMARY SFC FRONT FRONT WILL BE DRAPED
FROM THE UPPER MIDWEST SOUTHWEST INTO THE SOUTHERN PLAINS WITH A
MOIST/HUMID/UNSTABLE AIRMASS OUT AHEAD OF THIS.
THE REMAINDER OF THE AFTERNOON INTO EARLY THIS EVENING...
19Z REGIONAL RADAR MOSAIC SHOWING SCATTERED CONVECTION FIRING ACROSS
MUCH OF ILLINOIS IN A ZONE OF WEAK MOISTURE CONVERGENCE ON THE
EASTERN FLANK OF A CONVECTIVELY ENHANCED/INDUCED SHORTWAVE LIFTING
INTO WEST-CENTRAL ILLINOIS...WITH ISOLATED CONVECTION STARTING TO
POP ACROSS THE LOCAL AREA. LATEST RAP ANALYSIS SHOWS 1500-2000
J/KG OF MLCAPE ACROSS THE AREA WITH LITTLE/NO CIN. EXPECT ISOLATED
TO SCATTERED CONVECTION TO MAINLY IMPACT AREAS ALONG AND WEST OF
INTERSTATE 69 INTO THE EARLY EVENING AS WEAK FORCING AND CONTINUED
LOW/MID LEVEL THETA-E ADVECTION ADVECTS OVER THIS AREA. MARGINAL
20-25 KNOTS OF DEEP LAYER EFFECTIVE SHEAR A DEFINITE LIMITING
FACTOR FOR ORGANIZATION AND ISOLATED SEVERE STORMS...ALTHOUGH
CANNOT RULE OUT AN ISOLATED DAMAGING WIND/HAIL THREAT IF ANY
MULTICELL CLUSTERS/SMALL LINE SEGMENTS TAKE SHAPE.
LARGE SCALE UPPER SUPPORT WILL INCREASE TONIGHT INTO FRIDAY MORNING
AS A MORE PRONOUNCED MID LEVEL SHORTWAVE TROUGH NOW EJECTING INTO
THE CENTRAL PLAINS ON THE NOSE OF AN UPPER JET TRANSLATES NORTHEAST
INTO THE WESTERN/NORTHERN GREAT LAKES. THIS SUPPORTS THE IDEA OF
LATEST HI-RES GUIDANCE IN MAINTAINING A WEAKENING MESOSCALE
CONVECTIVE SYSTEM (ACROSS CENTRAL IOWA INTO WESTERN MISSOURI AS OF
THIS WRITING) EAST INTO AT LEAST OUR WESTERN ZONES AFTER 05/06Z ISH.
MEAGER MID LEVEL LAPSE RATES COUPLED WITH DIURNAL COOLING SHOULD
ALLOW WHAT MIGHT BE A LINE OF SEVERE CONVECTION INTO ILLINOIS THIS
EVENING TO WEAKEN (FALL APART?) AS IT ATTEMPTS TO MAKE INTO THE
LOCAL AREA FROM WEST TO EAST OVERNIGHT...WITH SHOWERS/ISO THUNDER
POSSIBLY LINGERING INTO FRIDAY MORNING ALONG THE MCS/MCV RESIDUAL
OUTFLOW BOUNDARY. BUMPED UP POPS A BIT AFTER MIDNIGHT....HIGHEST
WEST.
SUBSIDENCE/AVA BEHIND THE MID LEVEL TROUGH AXIS LATER FRIDAY MORNING
INTO THE EARLY/MID AFTERNOON HOURS WITH ATMOSPHERE POSSIBLY WORKED
OVER FROM MORNING CLOUDS/SHOWERS SHOULD RESULT IN A LULL IN PCPN
ACROSS THE AREA DURING THIS TIME. ALTHOUGH RETAINED LOW 20-30
PERCENT POPS BTW 15-21Z AS RENEWED CONVECTION COULD FORM ALONG THE
RESIDUAL OUTFLOW BOUNDARY BY EARLY/MID AFTERNOON...BEST CHANCES
ACROSS OUR SOUTHEASTERN ZONES. CHANCES FOR ADDITIONAL
CONVECTION...POTENTIALLY SEVERE...BY LATE AFTERNOON AND EVENING
ARE DISCUSSED IN THE LONG TERM SECTION.
&&
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 300 PM EDT THU MAY 30 2013
POTENT SW AND ATTENDANT CLOSED LOW OVR SD IS XCPD TO OPEN FRI NIGHT
AND KICK EWD ACRS THE LAKES IN RESPONSE OF ARRIVAL OF UPSTREAM
KICKER INTO THE PACNW. AT THE SFC...PRONOUNCED SFC WAVE OVR SRN MN
SAT MORNING WILL EJECT EWD TO LK HURON BY SUN MORNING AS ASSOCD
TRAILING CDFNT SURGES EWD.
BEST LL MSTR FLUX/LL THETA-E RIDGING XCPD FRI EVENING W/AGAIN A
CONDITIONAL SVR THREAT PENDING SHRT TERM CONV EVOLUTION/MAINTENANCE
INTO THE WRN LAKES FRI AFTN. OTRWS STG SFC CDFNT TO CROSS CWA SAT
AFTN/EVE W/STG FORCING FOR ASCENT WITHIN CONTD SIG LL MSTR PLUME AND
LIKELY MOST FVRBL WINDOW FOR SIG RAINFALL.
STG CAA FOLLOWS ON SUN W/RAPID NEWD ADVTN OF MID LVL DRYSLOT
UNDERNEATH MID LVL TROUGH PIVOTING THROUGH MI. GIVEN GENERAL 12Z
CONSENSUS SOLUTION WILL DROP LOW CHC POPS MOST AREAS SANS FAR SE.
DRY AND SEASONABLE WX XPCD THROUGH UNTIL THE END OF THE PD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 220 AM EDT FRI MAY 31 2013
MARGINAL INSTABILITY DOWNSTREAM OF ONGOING TSRA AT KSBN...WITH ONLY
TRAILING STRATIFORM SHRA EXPECTED BEYOND 07 UTC. RAMPED 50KT SWRLY
FLOW AT 8H SHOULD AID IN MAINTENANCE/SLOW DECAY OF SLIGHTLY MORE
ORGANIZED CONVECTION ACROSS WEST CENTRAL INDIANA...ASSOCIATED WITH
HIGHER POCKETS OF EFFECTIVE DEEP LAYER SHEAR ON ORDER OF
35KTS...SUCH THAT INCLUSION OF LOW/MEDIUM CONFIDENCE FOR TSRA INTO
KFWA IN 08-10 UTC TIMEFRAME...THOUGH BESIDES CONVECTIVELY INDUCED
HAZARDS ANTICIPATE ONLY A BRIEF HIGH END MVFR VSBY REDUCTION IN CELL
CENTROIDS. GREAT UNCERTAINTY AS A MULTITUDE OF LESS THAN STELLAR
MODEL INDICATIONS/CONVECTIVE TRENDS LATER TODAY BELIES MOST PROBABLE
OUTCOME. IMMEDIATE UPSTREAM DESTABILIZATION ACROSS MID MISSISSIPPI
VALLEY ALONG WITH MARKEDLY INCREASED DEEP LAYER SHEAR TO SUPPORT
STORM DEVELOPMENT BY LATE AFTERNOON/EVENING ACROSS IA/MO/IL AND INTO
NRN IN BY LATE EVENING THROUGH END OF FORECAST PERIOD WITH PSBL
LINEAR ORGANIZATION SUPPORTING STRONG WIND GUST RISK. TIMING TO
LIKELY CHANGE/EVOLVE IN SUBSEQUENT ISSUANCES AS NUANCES FROM EFFECTS
OF ONGOING CONVECTION BETTER DETERMINED.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SHORT TERM...STEINWEDEL
LONG TERM...T
AVIATION...MURPHY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1243 PM CDT FRI MAY 31 2013
.SHORT TERM.../TODAY /...
ISSUED AT 323 AM CDT FRI MAY 31 2013
THUNDERSTORMS HAVE DEVELOPED IN NORTHERN MISSOURI ALONG A ZONE OF
WARM AIR ADVECTION AND A LOW LEVEL JET. JUST NORTH OF THAT AREA BUT
STILL IN MO SOME WEAKER STORMS HAVE DEVELOPED AND ARE DISSIPATING.
THE STORMS HAVE AN EAST/NORTHEASTERLY TRACK AND WILL EVENTUALLY CLIP
FAR SOUTHERN IOWA. THE WEAKENING STORMS JUST ACROSS OUR BORDER WILL
LIKELY ONLY PRODUCE SOME SHOWERS ACROSS THE FAR SOUTH IN THE NEXT
FEW HOURS. A VORT MAX AND SHORT WAVE WILL PIVOT AROUND THE UPPER
LOW OVER THE EASTERN DAKOTAS AND THIS WILL SHIFT THE STORMS THAT ARE
A LITTLE FURTHER SOUTH IN NORTHERN MO RIGHT INTO SOUTHERN/SOUTHEAST
IOWA BY MID TO LATE MORNING THEN INTO EASTERN IOWA BY EARLY
AFTERNOON.
BY MID TO LATE AFTERNOON A STRONGER SHORT WAVE WILL PUSH INTO
WESTERN IOWA WHICH WILL BRING MORE THUNDERSTORMS TO THAT AREA AND
THIS WILL SHIFT EAST FROM 21Z INTO THE EVENING HOURS. THERE WILL BE
A TIME IN THE AFTERNOON WHERE SHOWERS AND STORMS WILL STILL BE OVER
EASTERN IOWA AND ADDITIONAL STORMS DEVELOPING OVER THE WEST WITH
CENTRAL IOWA DRY. LAPSE RATES OVER SOUTHERN IOWA AND ABOUT THE
SOUTHEAST THIRD OF THE STATE ARE PRETTY STEEP THIS AFTERNOON AND
THERE IS MORE THAN SUFFICIENT SHEAR FOR A FEW SEVERE STORMS. IN
ADDITION...HEAVY RAINFALL IS LIKELY WITH THE STORMS AS WELL...MAINLY
OVER THE FAR EAST AND SOUTHEAST.
YESTERDAY THE HI RES NMM EAST REALLY HAD THE PRECIP AREAS PEGGED AND
ALSO HAD DECENT TIMING OF THE PRECIP. I STILL LIKE WHAT THIS MODEL
DOES WITH THE PRECIP TODAY HOWEVER IT IS NOT PICKING UP THE MO
CONVECTION VERY WELL AT THIS TIME. IT IS ABOUT 3 HOURS LATER WITH
THAT SO I BLENDED NMM POPS WITH THE HRRR AND NAM12.
AS FOR TEMPS...THERE SHOULD BE SLIGHTLY WARMER AIR OVER THE SOUTH
AND SOUTHEAST TODAY SO I NUDGED HIGHS UP IN THESE AREAS. THE NORTH
SHOULD SEE TEMPS A FEW DEGREES WARMER AS WELL.
.LONG TERM.../TONIGHT THROUGH WEDNESDAY/...
ISSUED AT 323 AM CDT FRI MAY 31 2013
FEWER CONCERNS FOR THE NEXT SEVERAL DAYS AS UPPER TROUGH BEGINS TO
SWING EAST. ALREADY THE MAIN H850 MOISTURE CHANNEL HAS SHIFTED EAST
OF THE AREA WITH THE LINE OF STRONGER THUNDERSTORMS THAT EXITED THE
EASTERN PORTION OF THE FORECAST AREA EARLY THIS EVENING. HOWEVER
THERE WILL STILL BE SOME RESIDUAL CONVECTION FAR SOUTHEAST EARLY IN
THE PERIOD TONIGHT...ENDING QUICKLY AND MOVING EAST BY 06Z.
MEANWHILE...THE MAIN FEATURE YET LATE TONIGHT AND EARLY SATURDAY
WILL BE THE OLD H500 LOW WHICH IS LIKELY TO SPIN UP SOME SHOWERS AND
ISOLATED THUNDER AS IT MOVES ACROSS THE REGION TOMORROW AS THE COLD
POOL UNDERNEATH THE UPPER LEVEL LOW DROPS SOUTHEAST INTO THE REGION.
STEEP LAPSE RATES WILL BE IN THE AREA OF THE LOW ON SATURDAY AND
OVER THE NORTH INTO MN AND WESTERN WI NON SUPERCELL TORNADO PARAMETER
IS INCREASING. SOMETHING TO KEEP AN EYE ON THERE...AN ISOLATED
FUNNEL CLOUD OR LANDSPOUT MAY BE POSSIBLE IF LAPSE RATES BECOME
STEEP ENOUGH IN THE AFTERNOON HOURS. OTHERWISE...THE OLD LOW WILL
PULL EAST SATURDAY NIGHT AND SUNDAY LEAVING THE REGION WITH COOLER
AIR FOR THE FIRST PART OF JUNE. THIS WILL KEEP THE AREA IN THE 60S
FOR HIGHS ON SUNDAY WITH MID 40S NORTH AND LOWER 50S SOUTH FOR LOWS
ON MONDAY MORNING. AS THE HIGH MOVES EAST...HIGHS WILL RESPOND INTO
THE LOWER 70S FOR MONDAY. MONDAY NIGHT WARM AIR ADVECTION AND MID
LEVEL MOISTURE BEGIN TO INCREASE AGAIN...RESULTING IN LATE
NIGHT/EARLY MORNING ELEVATED CONVECTION. TUESDAY LOOKS ACTIVE AS A
STRONGER WAVE ROTATES NORTHEAST INTO THE STATE. THIS WILL RESULT IN
MORE WIDESPREAD THUNDERSTORMS WITH RAINFALL AMOUNTS POSSIBLY
APPROACHING ONE INCH IN SOME PLACES. THIS WILL CERTAINLY KEEP SOIL
MOISTURE HIGH...AND ALSO RESULT IN RENEWED RIVER RISES. THE SYSTEM
WILL GRADUALLY EXIT THE REGION BY THURSDAY. THE LARGER SCALE FLOW
PATTERN REMAINS GENERALLY WESTERLY AT MID TO HIGH LEVELS. THIS
PROMOTES LEE SIDE TROUGHING AND WITH A CONTINUED SUB TROPICAL HIGH
ANCHORED OFF THE EAST COAST A WETTER THAN NORMAL PATTERN IS LIKELY
TO CONTINUE OVER THE NEXT 7 TO 10 DAYS. ANOTHER INTERESTING WRINKLE
IS A TROPICAL DISTURBANCE IN THE GULF OF MEXICO BY NEXT THUR/FRIDAY
WHICH MAY EVENTUALLY BE PULLED NORTH TOWARD THE MID MISSISSIPPI
RIVER VALLEY. HIGH TEMPERATURES OVER THE NEXT WEEK WILL LIKELY
REMAIN IN THE 70S ON AVERAGE AND NOT BREAK OUT OF A 65 TO 75 RANGE
BY TOO MUCH IF ANY. ANOTHER NOTE WITH OUR CURRENT WET WEATHER WILL
BE CLOUD COVER. UNLESS WE HAVE A STRONG HIGH AND STRONG
SUBSIDENCE...MOST LATE MORNINGS AND AFTERNOONS ON ANY SUNNY DAY WILL
GO SCT TO BKN BY AFTERNOON.
&&
.AVIATION...31/18Z
ISSUED AT 1245 PM CDT FRI MAY 31 2013
A FEW SHOWERS AND THUNDERSTORMS STRETCHING ACROSS THE EASTERN
CWA...SHOULD MAINLY IMPACT KALO AND KOTM THROUGH MID AFTERNOON. A
FEW SCATTERED SHOWERS/ISOLATED THUNDERSTORMS MAY ALSO DEVELOP
ACROSS THE NORTH TOWARD LATE AFTERNOON POSSIBLE IMPACTING KFOD AND
KMCW. OTHERWISE MAINLY DRY CONDITIONS TONIGHT...WITH SOUTHERLY TO
SOUTHWESTERLY WINDS BECOMING WESTERLY TO NORTHWESTERLY SATURDAY.
MVFR TO LOW VFR CLOUDS EXPECTED TO IMPACT ENTIRE CWA SATURDAY AS
MAIN UPPER LEVEL SYSTEM CURRENTLY ACROSS THE DAKOTAS MOVES THROUGH
THE STATE.
&&
.HYDROLOGY...
ISSUED AT 323 AM CDT FRI MAY 31 2013
A FLASH FLOOD WATCH REMAINS IN EFFECT FOR BUTLER COUNTY AT THIS
TIME DUE TO THE SMALL BREACH IN THE LEVEE ALONG THE BEAVER CREEK
AT NEW HARTFORD.
A WEATHER DISTURBANCE CAUSING AN AREA OF THUNDERSTORMS FROM KANSAS
AND MISSOURI WILL ROTATE NORTHEAST TODAY...AFFECTING THE SOUTHEAST
HALF OF THE FORECAST AREA LATER THIS MORNING THROUGH THE AFTERNOON
HOURS. THE SOUTHEAST MAY SEE UP TO AN INCH OR MORE OF RAIN...BUT
CURRENT FLASH FLOOD GUIDANCE HAS INCREASED TO 1.3 TO 1.5 INCHES
PER HOUR AND 1.5 TO 2.25 INCHES IN 3 HOURS AT PRESENT. UNLESS THE
STORMS BACK BUILD...THE RISK FOR ANY FLASH FLOODING REMAINS LOW
TODAY ACROSS OUR FORECAST AREA.
RIVER FLOOD WARNINGS REMAIN IN EFFECT FOR NUMEROUS LOCATIONS
THROUGHOUT THE HYDROLOGICAL SERVICES AREA FOR THE NEXT 5 TO 6 DAYS.
IN THE SHORT TERM... THE OLD H500 LOW WILL CYCLE EAST IN THE NEXT 24
TO 48 HOURS AND THEN DEPART. WITH ONLY LIGHT SHOWERS OR ISOLATED
THUNDER EXPECTED... RAINFALL WILL REMAIN LIGHT. FOLLOWING
THAT...HIGH PRESSURE WILL KEEP THE REGION RAIN FREE TO MONDAY
EVENING. THIS WILL SLOWLY ALLEVIATE THE SOME OF THE WATER ISSUES
THOUGH LARGER MAIN STEM RIVER SYSTEMS WILL REMAIN ABOVE FLOOD STAGE
THROUGH THE FORECAST PERIOD. ADDITIONAL MODERATE RAINFALL IS LIKELY
BEGINNING LATE MONDAY NIGHT THROUGH THURSDAY WHICH WILL NEED TO BE
WATCHED.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 7 PM CDT THIS EVENING FOR SOUTHEASTERN BUTLER.
&&
$$
SHORT TERM...FAB
LONG TERM...REV
AVIATION...BEERENDS
HYDROLOGY...REV
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1231 PM CDT FRI MAY 31 2013
.UPDATE...
ISSUED AT 1220 PM CDT FRI MAY 31 2013
THE TWO SEPARATE MCS COMPLEXES HAVE MERGED AS EXPECTED. THUS THE
SOUTHEAST HALF OF THE CWFA HAS THE BETTER CHANCE AT SEEING
MODERATE RAIN WITH POSSIBLY VERY LOCALIZED HEAVY RAINFALL THROUGH
THE AFTERNOON HOURS.
NEW CONVECTION HAS DEVELOPED IN CENTRAL IOWA DUE TO CONVERGENCE OF
THE WIND FIELD. THE MCS/LIFT TOOLS ARE SUGGESTING THIS NEW
CONVECTION WILL MOVE INTO THE NORTHWEST PART OF THE CWFA BUT MAY
REMAIN WEAK. THE MCS MAY INDUCE NEW CONVECTION IN FAR NORTHWEST
ILLINOIS IN AREAS ALONG/EAST OF THE MISSISSIPPI.
THE KEY TO CONVECTIVE TRENDS THIS AFTERNOON WILL BE WHETHER OR NOT
CONVECTIVE TEMPERATURE IS ACHIEVED. FORECAST SOUNDINGS PLACE THE
CONVECTIVE TEMPERATURE IN THE UPPER 70S WHICH IS THE CURRENT FCST
MAX TEMPERATURE FOR MUCH OF THE AREA. STRONGER STORMS MAY BE
POSSIBLE IF STRONGER DIFFERENTIAL HEATING CAN OCCUR ACROSS THE
AREA. ..08..
UPDATE ISSUED AT 1036 AM CDT FRI MAY 31 2013
MCS TOOL FROM THE UKMET AND RAP ARE DEPICTING REASONABLY WELL THE
CURRENT WX. THE FIRST MCS IS MOVING ACROSS THE SOUTHERN CWFA
PRODUCING LIGHT TO MODERATE RAIN. SLIGHTLY DRIER AIR MIXING DOWN
ON THE NORTH SIDE IS RESULTING IN A BRIEF PERIOD OF HIGH WINDS.
THE TRENDS WITH THE RAP MODEL INDICATE THE NEW MCS ACROSS NORTHERN
MISSOURI WILL SLOWLY MERGE WITH THE FIRST MCS THROUGH LATE
MORNING. THE SOUTHEAST HALF OF THE CWFA WILL BE AFFECTED BY THE
COMBINED MCS WITH IT EXITING THE CWFA BY EARLY EVENING. THUS THIS
AREA WILL SEE THE MORE WIDESPREAD AND POTENTIALLY HEAVY RAINFALL.
FLOW BASED OFF THE SFC OBS THROUGH 15Z INDICATE THE CLEAR AREAS
ACROSS CENTRAL/NORTHERN IOWA WILL FILL WITH CLOUDS AS THE MORNING
AND AFTERNOON PROGRESS. THE LIFT TOOL SUGGESTS THE POTENTIAL FOR
NEW CONVECTION DEVELOPING AHEAD OF THE APPROACHING FRONT.
AS FOR THE FLASH FLOOD HEADLINES...THEY ARE BEING LEFT IN PLACE
FOR NOW. DEPENDING UPON HOW CONVECTION EVOLVES DURING THE LATE
MORNING AND AFTERNOON...THE POSSIBILITY EXISTS THAT SOME HEADLINES
MAY BE DROPPED. ..08..
UPDATE ISSUED AT 642 AM CDT FRI MAY 31 2013
IMPULSE MOVING AROUND THE BASE OF THE TROUGH WAS PUSHING INTO NW
MO AND WILL BE HEADING NORTHEAST INTO THE DVN CWA LATER THIS
MORNING. RAP MODEL INCREASES THE LOW LEVEL JET SO THUNDERSTORMS
SHOULD CONTINUE TO SPREAD NORTHEAST INTO THE CWA THIS MORNING AND
THEN INCREASE IN COVERAGE/INTENSITY THIS AFTERNOON.
&&
.SYNOPSIS...
ISSUED AT 315 AM CDT FRI MAY 31 2013
ALL IS QUIET FOR NOW ACROSS THE DVN CWA EARLY THIS MORNING BUT
THUNDERSTORMS WERE LINED UP FROM NORTHEAST IL INTO AR MOVING
NORTHEAST. OTHER THUNDERSTORMS WERE FORMING IN EXTREME NW MO AND
NORTHEAST KS. A SUPERCELL WAS PRODUCING LARGE HAIL AROUND TOPEKA
AND THESE STORMS WERE SPREADING EAST/NORTHEAST AT 40 KNOTS. STRONG LOW
PRESSURE WAS SPINNING OVER THE DAKOTAS WITH A COLD FRONT IN THE
PLAINS. CURRENT TEMPERATURES WERE IN THE 60S ACROSS IA...MO...KS
AND IN THE 70S IN THE SOUTHERN PLAINS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 315 AM CDT FRI MAY 31 2013
HEADLINES...WILL CONTINUE THE FLASH FLOOD WATCH TODAY THROUGH
TONIGHT.
FORECAST FOCUS ON ACTIVE SEVERE WEATHER TODAY INTO THIS EVENING
AND POTENTIAL FOR FLASH FLOODING ESPECIALLY WHERE TRAINING STORMS
OCCUR.
TODAY...SHOULD BE JUST ENOUGH SUNSHINE THIS MORNING TO PUSH
TEMPERATURES INTO THE LOWER TO MID 70S THIS MORNING WITH THE
CONVECTIVE TEMPERATURE REACHED. THUNDERSTORM ACTIVITY TO OUR
SOUTHWEST SHOULD QUICKLY PUSH INTO THE DVN CWA THIS MORNING.
AIR MASS WILL BE DESTABILIZING ALLOWING FOR THUNDERSTORMS TO
INTENSIFY. MODERATE TO STRONG DEEP LAYER SHEAR AND DRY AIR ALOFT
AND FREEZING LEVEL AT 11-12K FT SHOULD BE IDEAL FOR LARGE HAIL
LATER THIS MORNING...POTENTIALLY QUARTER TO GOLF BALL SIZE.
THIS AFTERNOON...WINDS ALOFT BECOME MORE UNIDIRECTIONAL WITH MID
LEVEL WINDS INCREASING TO OVER 70 KNOTS. THIS WOULD FAVOR BOWING
SEGMENTS AND DAMAGING WINDS GREATER THAN 70-80 MPH. WITH THE
GROUND SATURATED THIS WOULD EASILY KNOCK OVER LARGE TREES. WITH
SUCH STRONG SHEAR ANY DISCRETE THUNDERSTORM MAY BECOME
SUPERCELLULAR WITH THE POTENTIAL FOR TORNADOES/LARGE HAIL...ALSO
IN ANY LEWP/BOWING SEGMENTS. THUNDERSTORMS WILL BE FAST MOVING BUT
ANY TRAINING OF STORMS WOULD ENHANCE THE FLASH FLOOD THREAT.
OPERATIONAL MODELS SUGGEST THE HIGHEST RAIN TOTALS TO BE ACROSS
ABOUT OUR SOUTHEAST HALF CWA. HIGHS TODAY AROUND 80.
TONIGHT...ACTIVE THUNDERSTORMS THIS EVENING SHOULD BE MAINLY IN
OUR IL COUNTIES WITH ACTIVITY THEN PUSHING EAST OF THE DVN CWA BY
MIDNIGHT. COLD FRONT WILL BE MOVING INTO EASTERN IA LATER TONIGHT
BRINGING COOLER AND DRIER AIR INTO EASTERN IA. MINIMUM TEMPERATURES
WILL RANGE FROM THE UPPER 50S WEST TO MID 60S EAST.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 315 AM CDT FRI MAY 31 2013
SATURDAY...THE SURFACE COLD FRONT IS PROGGED TO BE NEAR THE
MISSISSIPPI RIVER AT 12Z SATURDAY. THE COLD FRONT WILL CONTINUE TO
SLIDE EAST DURING THE DAY AS THE UPPER TROUGH AXIS SHIFTS EAST
ACROSS IOWA. THE CHANCE FOR SOME SHOWERS AND STORMS WILL CONTINUE IN
THE VICINITY OF THE SURFACE FRONT EARLY SATURDAY. WILL HOLD ONTO
SOME SLIGHT TO CHANCE CATEGORY PRECIPITATION PROBABILITIES THROUGH
THE REMAINDER OF SATURDAY AS THE MID LEVEL BOUNDARY AND UPPER TROUGH
ENERGY WORK ACROSS THE FORECAST AREA. HOWEVER ANY SHOWERS OR STORMS
ON SATURDAY WILL BE LACKING IN HEAVY RAIN OR SEVERE POTENTIAL.
TEMPERATURES SATURDAY ARE A BIT OF A CHALLENGE WITH CLOUD COVER AND
COLDER AIR STARTING TO WORK IN BEHIND THE FRONT.
SUNDAY THROUGH MONDAY...A BRIEF RESPITE IN THE ACTIVE WEATHER
PATTERN IS IN STORE FROM SUNDAY INTO MONDAY. COOLER AND DRIER AIR
WILL MOVE IN AS UPPER RIDGING AND SURFACE HIGH PRESSURE SPREAD
ACROSS THE REGION. TEMPERATURES ON SUNDAY LOOK TO BE AROUND 10
DEGREES BELOW NORMAL...WITH MORNING LOWS IN THE LOWER TO MIDDLE 50S
AND HIGHS IN THE MIDDLE TO UPPER 60S. MONDAY MORNING TEMPERATURES
COULD BOTTOM OUT IN THE 40S ACROSS PORTIONS OF THE FORECAST AREA.
TUESDAY THROUGH THURSDAY...YET ANOTHER UPPER LEVEL SYSTEM WILL
APPROACH THE MIDWEST MID TO LATE NEXT WEEK. LEAD SHORTWAVE ENERGY
COULD KICK OFF SOME PRECIPITATION AS EARLY AS TUESDAY...WITH
INCREASING SHOWER AND THUNDERSTORM CHANCES BY WEDNESDAY. A WARMING
TREND WILL BRING TEMPERATURES BACK CLOSER TO NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1220 PM CDT FRI MAY 31 2013
TWO SEPARATE THUNDERSTORM COMPLEXES HAVE MERGED OVER SOUTHEAST
IOWA AND WESTERN ILLINOIS. GENERALLY VFR WX WILL BE SEEN THROUGH
00Z/01. TSRA WILL BE POSSIBLE WITH KMLI/KBRL HAVING A BETTER
CHANCE THAN KCID/KDBQ. IF A TSRA AFFECTS A TAF SITE A BRIEF PERIOD
OF MVFR CONDITIONS ARE POSSIBLE. AFT 00Z/01 VFR CONDITIONS ARE
EXPECTED TO CONTINUE. WET GROUND MAY RESULT IN MVFR CONDITIONS
DVLPG AFT 06Z/01 DUE TO MAINLY CLEAR SKIES AND WINDS UNDER 10
KNOTS. ..08..
&&
.HYDROLOGY...
ISSUED AT 315 AM CDT FRI MAY 31 2013
WITH MANY RIVERS IN MODERATE TO MAJOR FLOOD AND THE GROUND
COMPLETELY SATURATED THE THREAT FOR FLASH FLOODING WILL REMAIN
TODAY INTO THIS EVENING...ESPECIALLY WHERE TRAINING OF STORMS
OCCUR. THE HEAVIEST RAINS SHOULD BE ACROSS THE SOUTHEAST HALF OF
THE DVN CWA WHERE MANY AREAS SHOULD RECEIVE AT LEAST AN INCH OF
RAIN TODAY INTO THIS EVENING. HOWEVER...SEVERAL INCHES OF RAIN
WOULD PRODUCE SEVERE FLASH FLOODING ESPECIALLY IF STORMS CAN TRAIN
ACROSS THE SAME LOCATIONS.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR BENTON-BUCHANAN-
CEDAR-CLINTON-DELAWARE-DES MOINES-DUBUQUE-HENRY IA-IOWA-
JACKSON-JEFFERSON-JOHNSON-JONES-KEOKUK-LEE-LINN-LOUISA-
MUSCATINE-SCOTT-VAN BUREN-WASHINGTON.
IL...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR BUREAU-CARROLL-
HANCOCK-HENDERSON-HENRY IL-JO DAVIESS-MCDONOUGH-MERCER-
PUTNAM-ROCK ISLAND-STEPHENSON-WARREN-WHITESIDE.
MO...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR CLARK-SCOTLAND.
&&
$$
UPDATE...08
SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...STOFLET
AVIATION...08
HYDROLOGY...HAASE
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1048 AM CDT FRI MAY 31 2013
.UPDATE...
ISSUED AT 1036 AM CDT FRI MAY 31 2013
MCS TOOL FROM THE UKMET AND RAP ARE DEPICTING REASONABLY WELL THE
CURRENT WX. THE FIRST MCS IS MOVING ACROSS THE SOUTHERN CWFA
PRODUCING LIGHT TO MODERATE RAIN. SLIGHTLY DRIER AIR MIXING DOWN
ON THE NORTH SIDE IS RESULTING IN A BRIEF PERIOD OF HIGH WINDS.
THE TRENDS WITH THE RAP MODEL INDICATE THE NEW MCS ACROSS NORTHERN
MISSOURI WILL SLOWLY MERGE WITH THE FIRST MCS THROUGH LATE
MORNING. THE SOUTHEAST HALF OF THE CWFA WILL BE AFFECTED BY THE
COMBINED MCS WITH IT EXITING THE CWFA BY EARLY EVENING. THUS THIS
AREA WILL SEE THE MORE WIDESPREAD AND POTENTIALLY HEAVY RAINFALL.
FLOW BASED OFF THE SFC OBS THROUGH 15Z INDICATE THE CLEAR AREAS
ACROSS CENTRAL/NORTHERN IOWA WILL FILL WITH CLOUDS AS THE MORNING
AND AFTERNOON PROGRESS. THE LIFT TOOL SUGGESTS THE POTENTIAL FOR
NEW CONVECTION DEVELOPING AHEAD OF THE APPROACHING FRONT.
AS FOR THE FLASH FLOOD HEADLINES...THEY ARE BEING LEFT IN PLACE
FOR NOW. DEPENDING UPON HOW CONVECTION EVOLVES DURING THE LATE
MORNING AND AFTERNOON...THE POSSIBILITY EXISTS THAT SOME HEADLINES
MAY BE DROPPED. ..08..
UPDATE ISSUED AT 642 AM CDT FRI MAY 31 2013
IMPULSE MOVING AROUND THE BASE OF THE TROUGH WAS PUSHING INTO NW
MO AND WILL BE HEADING NORTHEAST INTO THE DVN CWA LATER THIS
MORNING. RAP MODEL INCREASES THE LOW LEVEL JET SO THUNDERSTORMS
SHOULD CONTINUE TO SPREAD NORTHEAST INTO THE CWA THIS MORNING AND
THEN INCREASE IN COVERAGE/INTENSITY THIS AFTERNOON.
&&
.SYNOPSIS...
ISSUED AT 315 AM CDT FRI MAY 31 2013
ALL IS QUIET FOR NOW ACROSS THE DVN CWA EARLY THIS MORNING BUT
THUNDERSTORMS WERE LINED UP FROM NORTHEAST IL INTO AR MOVING
NORTHEAST. OTHER THUNDERSTORMS WERE FORMING IN EXTREME NW MO AND
NORTHEAST KS. A SUPERCELL WAS PRODUCING LARGE HAIL AROUND TOPEKA
AND THESE STORMS WERE SPREADING EAST/NORTHEAST AT 40 KNOTS. STRONG LOW
PRESSURE WAS SPINNING OVER THE DAKOTAS WITH A COLD FRONT IN THE
PLAINS. CURRENT TEMPERATURES WERE IN THE 60S ACROSS IA...MO...KS
AND IN THE 70S IN THE SOUTHERN PLAINS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 315 AM CDT FRI MAY 31 2013
HEADLINES...WILL CONTINUE THE FLASH FLOOD WATCH TODAY THROUGH
TONIGHT.
FORECAST FOCUS ON ACTIVE SEVERE WEATHER TODAY INTO THIS EVENING
AND POTENTIAL FOR FLASH FLOODING ESPECIALLY WHERE TRAINING STORMS
OCCUR.
TODAY...SHOULD BE JUST ENOUGH SUNSHINE THIS MORNING TO PUSH
TEMPERATURES INTO THE LOWER TO MID 70S THIS MORNING WITH THE
CONVECTIVE TEMPERATURE REACHED. THUNDERSTORM ACTIVITY TO OUR
SOUTHWEST SHOULD QUICKLY PUSH INTO THE DVN CWA THIS MORNING.
AIR MASS WILL BE DESTABILIZING ALLOWING FOR THUNDERSTORMS TO
INTENSIFY. MODERATE TO STRONG DEEP LAYER SHEAR AND DRY AIR ALOFT
AND FREEZING LEVEL AT 11-12K FT SHOULD BE IDEAL FOR LARGE HAIL
LATER THIS MORNING...POTENTIALLY QUARTER TO GOLF BALL SIZE.
THIS AFTERNOON...WINDS ALOFT BECOME MORE UNIDIRECTIONAL WITH MID
LEVEL WINDS INCREASING TO OVER 70 KNOTS. THIS WOULD FAVOR BOWING
SEGMENTS AND DAMAGING WINDS GREATER THAN 70-80 MPH. WITH THE
GROUND SATURATED THIS WOULD EASILY KNOCK OVER LARGE TREES. WITH
SUCH STRONG SHEAR ANY DISCRETE THUNDERSTORM MAY BECOME
SUPERCELLULAR WITH THE POTENTIAL FOR TORNADOES/LARGE HAIL...ALSO
IN ANY LEWP/BOWING SEGMENTS. THUNDERSTORMS WILL BE FAST MOVING BUT
ANY TRAINING OF STORMS WOULD ENHANCE THE FLASH FLOOD THREAT.
OPERATIONAL MODELS SUGGEST THE HIGHEST RAIN TOTALS TO BE ACROSS
ABOUT OUR SOUTHEAST HALF CWA. HIGHS TODAY AROUND 80.
TONIGHT...ACTIVE THUNDERSTORMS THIS EVENING SHOULD BE MAINLY IN
OUR IL COUNTIES WITH ACTIVITY THEN PUSHING EAST OF THE DVN CWA BY
MIDNIGHT. COLD FRONT WILL BE MOVING INTO EASTERN IA LATER TONIGHT
BRINGING COOLER AND DRIER AIR INTO EASTERN IA. MINIMUM TEMPERATURES
WILL RANGE FROM THE UPPER 50S WEST TO MID 60S EAST.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 315 AM CDT FRI MAY 31 2013
SATURDAY...THE SURFACE COLD FRONT IS PROGGED TO BE NEAR THE
MISSISSIPPI RIVER AT 12Z SATURDAY. THE COLD FRONT WILL CONTINUE TO
SLIDE EAST DURING THE DAY AS THE UPPER TROUGH AXIS SHIFTS EAST
ACROSS IOWA. THE CHANCE FOR SOME SHOWERS AND STORMS WILL CONTINUE IN
THE VICINITY OF THE SURFACE FRONT EARLY SATURDAY. WILL HOLD ONTO
SOME SLIGHT TO CHANCE CATEGORY PRECIPITATION PROBABILITIES THROUGH
THE REMAINDER OF SATURDAY AS THE MID LEVEL BOUNDARY AND UPPER TROUGH
ENERGY WORK ACROSS THE FORECAST AREA. HOWEVER ANY SHOWERS OR STORMS
ON SATURDAY WILL BE LACKING IN HEAVY RAIN OR SEVERE POTENTIAL.
TEMPERATURES SATURDAY ARE A BIT OF A CHALLENGE WITH CLOUD COVER AND
COLDER AIR STARTING TO WORK IN BEHIND THE FRONT.
SUNDAY THROUGH MONDAY...A BRIEF RESPITE IN THE ACTIVE WEATHER
PATTERN IS IN STORE FROM SUNDAY INTO MONDAY. COOLER AND DRIER AIR
WILL MOVE IN AS UPPER RIDGING AND SURFACE HIGH PRESSURE SPREAD
ACROSS THE REGION. TEMPERATURES ON SUNDAY LOOK TO BE AROUND 10
DEGREES BELOW NORMAL...WITH MORNING LOWS IN THE LOWER TO MIDDLE 50S
AND HIGHS IN THE MIDDLE TO UPPER 60S. MONDAY MORNING TEMPERATURES
COULD BOTTOM OUT IN THE 40S ACROSS PORTIONS OF THE FORECAST AREA.
TUESDAY THROUGH THURSDAY...YET ANOTHER UPPER LEVEL SYSTEM WILL
APPROACH THE MIDWEST MID TO LATE NEXT WEEK. LEAD SHORTWAVE ENERGY
COULD KICK OFF SOME PRECIPITATION AS EARLY AS TUESDAY...WITH
INCREASING SHOWER AND THUNDERSTORM CHANCES BY WEDNESDAY. A WARMING
TREND WILL BRING TEMPERATURES BACK CLOSER TO NORMAL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 642 AM CDT FRI MAY 31 2013
IFR/MVFR CONDITIONS THIS MORNING WITH ANOTHER LARGE AND VIGOROUS
CONVECTIVE COMPLEX IMPACTING ALL TERMINALS BETWEEN 31/15Z AND
01/03Z WITH PERIODS OF MVF OR EVEN IFR CONDITIONS IN THE HEAVIEST
AND STRONGEST STORMS DUE TO HEAVY RAINS. SOUTH WINDS WILL CONTINUE
OUTSIDE OF ANY STORMS AT 5 TO 10 KTS. STRONGEST STORMS MAY ALSO
PRODUCE WIND GUSTS AOA 40 KTS AND POSSIBLY LARGE HAIL.
&&
.HYDROLOGY...
ISSUED AT 315 AM CDT FRI MAY 31 2013
WITH MANY RIVERS IN MODERATE TO MAJOR FLOOD AND THE GROUND
COMPLETELY SATURATED THE THREAT FOR FLASH FLOODING WILL REMAIN
TODAY INTO THIS EVENING...ESPECIALLY WHERE TRAINING OF STORMS
OCCUR. THE HEAVIEST RAINS SHOULD BE ACROSS THE SOUTHEAST HALF OF
THE DVN CWA WHERE MANY AREAS SHOULD RECEIVE AT LEAST AN INCH OF
RAIN TODAY INTO THIS EVENING. HOWEVER...SEVERAL INCHES OF RAIN
WOULD PRODUCE SEVERE FLASH FLOODING ESPECIALLY IF STORMS CAN TRAIN
ACROSS THE SAME LOCATIONS.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR BENTON-BUCHANAN-
CEDAR-CLINTON-DELAWARE-DES MOINES-DUBUQUE-HENRY IA-IOWA-
JACKSON-JEFFERSON-JOHNSON-JONES-KEOKUK-LEE-LINN-LOUISA-
MUSCATINE-SCOTT-VAN BUREN-WASHINGTON.
IL...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR BUREAU-CARROLL-
HANCOCK-HENDERSON-HENRY IL-JO DAVIESS-MCDONOUGH-MERCER-
PUTNAM-ROCK ISLAND-STEPHENSON-WARREN-WHITESIDE.
MO...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR CLARK-SCOTLAND.
&&
$$
UPDATE...08
SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...STOFLET
AVIATION...HAASE
HYDROLOGY...HAASE
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
649 AM CDT FRI MAY 31 2013
.UPDATE...
ISSUED AT 642 AM CDT FRI MAY 31 2013
IMPULSE MOVING AROUND THE BASE OF THE TROUGH WAS PUSHING INTO NW
MO AND WILL BE HEADING NORTHEAST INTO THE DVN CWA LATER THIS
MORING. RAP MODEL INCREASES THE LOW LEVEL JET SO THUNDERSTORMS
SHOULD CONTINUE TO SPREAD NORTHEAST INTO THE CWA THIS MORNING AND
THEN INCREASE IN COVERAGE/INTENSITY THIS AFTERNOON.
&&
.SYNOPSIS...
ISSUED AT 315 AM CDT FRI MAY 31 2013
ALL IS QUIET FOR NOW ACROSS THE DVN CWA EARLY THIS MORNING BUT
THUNDERSTORMS WERE LINED UP FROM NORTHEAST IL INTO AR MOVING
NORTHEAST. OTHER THUNDERSTORMS WERE FORMING IN EXTREME NW MO AND
NORTHEAST KS. A SUPERCELL WAS PRODUCING LARGE HAIL AROUND TOPEKA
AND THESE STORMS WERE SPREADING EAST/NORTHEAST AT 40 KNOTS. STRONG LOW
PRESSURE WAS SPINNING OVER THE DAKOTAS WITH A COLD FRONT IN THE
PLAINS. CURRENT TEMPERATURES WERE IN THE 60S ACROSS IA...MO...KS
AND IN THE 70S IN THE SOUTHERN PLAINS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 315 AM CDT FRI MAY 31 2013
HEADLINES...WILL CONTINUE THE FLASH FLOOD WATCH TODAY THROUGH
TONIGHT.
FORECAST FOCUS ON ACTIVE SEVERE WEATHER TODAY INTO THIS EVENING
AND POTENTIAL FOR FLASH FLOODING ESPECIALLY WHERE TRAINING STORMS
OCCUR.
TODAY...SHOULD BE JUST ENOUGH SUNSHINE THIS MORNING TO PUSH
TEMPERATURES INTO THE LOWER TO MID 70S THIS MORNING WITH THE
CONVECTIVE TEMPERATURE REACHED. THUNDERSTORM ACTIVITY TO OUR
SOUTHWEST SHOULD QUICKLY PUSH INTO THE DVN CWA THIS MORNING.
AIR MASS WILL BE DESTABILIZING ALLOWING FOR THUNDERSTORMS TO
INTENSIFY. MODERATE TO STRONG DEEP LAYER SHEAR AND DRY AIR ALOFT
AND FREEZING LEVEL AT 11-12K FT SHOULD BE IDEAL FOR LARGE HAIL
LATER THIS MORNING...POTENTIALLY QUARTER TO GOLF BALL SIZE.
THIS AFTERNOON...WINDS ALOFT BECOME MORE UNIDIRECTIONAL WITH MID
LEVEL WINDS INCREASING TO OVER 70 KNOTS. THIS WOULD FAVOR BOWING
SEGMENTS AND DAMAGING WINDS GREATER THAN 70-80 MPH. WITH THE
GROUND SATURATED THIS WOULD EASILY KNOCK OVER LARGE TREES. WITH
SUCH STRONG SHEAR ANY DISCRETE THUNDERSTORM MAY BECOME
SUPERCELLULAR WITH THE POTENTIAL FOR TORNADOES/LARGE HAIL...ALSO
IN ANY LEWP/BOWING SEGMENTS. THUNDERSTORMS WILL BE FAST MOVING BUT
ANY TRAINING OF STORMS WOULD ENHANCE THE FLASH FLOOD THREAT.
OPERATIONAL MODELS SUGGEST THE HIGHEST RAIN TOTALS TO BE ACROSS
ABOUT OUR SOUTHEAST HALF CWA. HIGHS TODAY AROUND 80.
TONIGHT...ACTIVE THUNDERSTORMS THIS EVENING SHOULD BE MAINLY IN
OUR IL COUNTIES WITH ACTIVITY THEN PUSHING EAST OF THE DVN CWA BY
MIDNIGHT. COLD FRONT WILL BE MOVING INTO EASTERN IA LATER TONIGHT
BRINGING COOLER AND DRIER AIR INTO EASTERN IA. MINIMUM TEMPERATURES
WILL RANGE FROM THE UPPER 50S WEST TO MID 60S EAST.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 315 AM CDT FRI MAY 31 2013
SATURDAY...THE SURFACE COLD FRONT IS PROGGED TO BE NEAR THE
MISSISSIPPI RIVER AT 12Z SATURDAY. THE COLD FRONT WILL CONTINUE TO
SLIDE EAST DURING THE DAY AS THE UPPER TROUGH AXIS SHIFTS EAST
ACROSS IOWA. THE CHANCE FOR SOME SHOWERS AND STORMS WILL CONTINUE IN
THE VICINITY OF THE SURFACE FRONT EARLY SATURDAY. WILL HOLD ONTO
SOME SLIGHT TO CHANCE CATEGORY PRECIPITATION PROBABILITIES THROUGH
THE REMAINDER OF SATURDAY AS THE MID LEVEL BOUNDARY AND UPPER TROUGH
ENERGY WORK ACROSS THE FORECAST AREA. HOWEVER ANY SHOWERS OR STORMS
ON SATURDAY WILL BE LACKING IN HEAVY RAIN OR SEVERE POTENTIAL.
TEMPERATURES SATURDAY ARE A BIT OF A CHALLENGE WITH CLOUD COVER AND
COLDER AIR STARTING TO WORK IN BEHIND THE FRONT.
SUNDAY THROUGH MONDAY...A BRIEF RESPITE IN THE ACTIVE WEATHER
PATTERN IS IN STORE FROM SUNDAY INTO MONDAY. COOLER AND DRIER AIR
WILL MOVE IN AS UPPER RIDGING AND SURFACE HIGH PRESSURE SPREAD
ACROSS THE REGION. TEMPERATURES ON SUNDAY LOOK TO BE AROUND 10
DEGREES BELOW NORMAL...WITH MORNING LOWS IN THE LOWER TO MIDDLE 50S
AND HIGHS IN THE MIDDLE TO UPPER 60S. MONDAY MORNING TEMPERATURES
COULD BOTTOM OUT IN THE 40S ACROSS PORTIONS OF THE FORECAST AREA.
TUESDAY THROUGH THURSDAY...YET ANOTHER UPPER LEVEL SYSTEM WILL
APPROACH THE MIDWEST MID TO LATE NEXT WEEK. LEAD SHORTWAVE ENERGY
COULD KICK OFF SOME PRECIPITATION AS EARLY AS TUESDAY...WITH
INCREASING SHOWER AND THUNDERSTORM CHANCES BY WEDNESDAY. A WARMING
TREND WILL BRING TEMPERATURES BACK CLOSER TO NORMAL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 642 AM CDT FRI MAY 31 2013
IFR/MVFR CONDITIONS THIS MORNING WITH ANOTHER LARGE AND VIGOROUS
CONVECTIVE COMPLEX IMPACTING ALL TERMINALS BETWEEN 31/15Z AND
01/03Z WITH PERIODS OF MVF OR EVEN IFR CONDITIONS IN THE HEAVIEST
AND STRONGEST STORMS DUE TO HEAVY RAINS. SOUTH WINDS WILL CONTINUE
OUTSIDE OF ANY STORMS AT 5 TO 10 KTS. STRONGEST STORMS MAY ALSO
PRODUCE WIND GUSTS AOA 40 KTS AND POSSIBLY LARGE HAIL.
&&
.HYDROLOGY...
ISSUED AT 315 AM CDT FRI MAY 31 2013
WITH MANY RIVERS IN MODERATE TO MAJOR FLOOD AND THE GROUND
COMPLETELY SATURATED THE THREAT FOR FLASH FLOODING WILL REMAIN
TODAY INTO THIS EVENING...ESPECIALLY WHERE TRAINING OF STORMS
OCCUR. THE HEAVIEST RAINS SHOULD BE ACROSS THE SOUTHEAST HALF OF
THE DVN CWA WHERE MANY AREAS SHOULD RECEIVE AT LEAST AN INCH OF
RAIN TODAY INTO THIS EVENING. HOWEVER...SEVERAL INCHES OF RAIN
WOULD PRODUCE SEVERE FLASH FLOODING ESPECIALLY IF STORMS CAN TRAIN
ACROSS THE SAME LOCATIONS.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR BENTON-BUCHANAN-
CEDAR-CLINTON-DELAWARE-DES MOINES-DUBUQUE-HENRY IA-IOWA-
JACKSON-JEFFERSON-JOHNSON-JONES-KEOKUK-LEE-LINN-LOUISA-
MUSCATINE-SCOTT-VAN BUREN-WASHINGTON.
IL...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR BUREAU-CARROLL-
HANCOCK-HENDERSON-HENRY IL-JO DAVIESS-MCDONOUGH-MERCER-
PUTNAM-ROCK ISLAND-STEPHENSON-WARREN-WHITESIDE.
MO...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR CLARK-SCOTLAND.
&&
$$
UPDATE...HAASE
SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...STOFLET
AVIATION...HAASE
HYDROLOGY...HAASE
AREA FORECAST DISCUSSION
NWS DES MOINES IA
648 AM CDT FRI MAY 31 2013
.SHORT TERM.../TODAY /...
ISSUED AT 323 AM CDT FRI MAY 31 2013
THUNDERSTORMS HAVE DEVELOPED IN NORTHERN MISSOURI ALONG A ZONE OF
WARM AIR ADVECTION AND A LOW LEVEL JET. JUST NORTH OF THAT AREA BUT
STILL IN MO SOME WEAKER STORMS HAVE DEVELOPED AND ARE DISSIPATING.
THE STORMS HAVE AN EAST/NORTHEASTERLY TRACK AND WILL EVENTUALLY CLIP
FAR SOUTHERN IOWA. THE WEAKENING STORMS JUST ACROSS OUR BORDER WILL
LIKELY ONLY PRODUCE SOME SHOWERS ACROSS THE FAR SOUTH IN THE NEXT
FEW HOURS. A VORT MAX AND SHORT WAVE WILL PIVOT AROUND THE UPPER
LOW OVER THE EASTERN DAKOTAS AND THIS WILL SHIFT THE STORMS THAT ARE
A LITTLE FURTHER SOUTH IN NORTHERN MO RIGHT INTO SOUTHERN/SOUTHEAST
IOWA BY MID TO LATE MORNING THEN INTO EASTERN IOWA BY EARLY
AFTERNOON.
BY MID TO LATE AFTERNOON A STRONGER SHORT WAVE WILL PUSH INTO
WESTERN IOWA WHICH WILL BRING MORE THUNDERSTORMS TO THAT AREA AND
THIS WILL SHIFT EAST FROM 21Z INTO THE EVENING HOURS. THERE WILL BE
A TIME IN THE AFTERNOON WHERE SHOWERS AND STORMS WILL STILL BE OVER
EASTERN IOWA AND ADDITIONAL STORMS DEVELOPING OVER THE WEST WITH
CENTRAL IOWA DRY. LAPSE RATES OVER SOUTHERN IOWA AND ABOUT THE
SOUTHEAST THIRD OF THE STATE ARE PRETTY STEEP THIS AFTERNOON AND
THERE IS MORE THAN SUFFICIENT SHEAR FOR A FEW SEVERE STORMS. IN
ADDITION...HEAVY RAINFALL IS LIKELY WITH THE STORMS AS WELL...MAINLY
OVER THE FAR EAST AND SOUTHEAST.
YESTERDAY THE HI RES NMM EAST REALLY HAD THE PRECIP AREAS PEGGED AND
ALSO HAD DECENT TIMING OF THE PRECIP. I STILL LIKE WHAT THIS MODEL
DOES WITH THE PRECIP TODAY HOWEVER IT IS NOT PICKING UP THE MO
CONVECTION VERY WELL AT THIS TIME. IT IS ABOUT 3 HOURS LATER WITH
THAT SO I BLENDED NMM POPS WITH THE HRRR AND NAM12.
AS FOR TEMPS...THERE SHOULD BE SLIGHTLY WARMER AIR OVER THE SOUTH
AND SOUTHEAST TODAY SO I NUDGED HIGHS UP IN THESE AREAS. THE NORTH
SHOULD SEE TEMPS A FEW DEGREES WARMER AS WELL.
.LONG TERM.../TONIGHT THROUGH WEDNESDAY/...
ISSUED AT 323 AM CDT FRI MAY 31 2013
FEWER CONCERNS FOR THE NEXT SEVERAL DAYS AS UPPER TROUGH BEGINS TO
SWING EAST. ALREADY THE MAIN H850 MOISTURE CHANNEL HAS SHIFTED EAST
OF THE AREA WITH THE LINE OF STRONGER THUNDERSTORMS THAT EXITED THE
EASTERN PORTION OF THE FORECAST AREA EARLY THIS EVENING. HOWEVER
THERE WILL STILL BE SOME RESIDUAL CONVECTION FAR SOUTHEAST EARLY IN
THE PERIOD TONIGHT...ENDING QUICKLY AND MOVING EAST BY 06Z.
MEANWHILE...THE MAIN FEATURE YET LATE TONIGHT AND EARLY SATURDAY
WILL BE THE OLD H500 LOW WHICH IS LIKELY TO SPIN UP SOME SHOWERS AND
ISOLATED THUNDER AS IT MOVES ACROSS THE REGION TOMORROW AS THE COLD
POOL UNDERNEATH THE UPPER LEVEL LOW DROPS SOUTHEAST INTO THE REGION.
STEEP LAPSE RATES WILL BE IN THE AREA OF THE LOW ON SATURDAY AND
OVER THE NORTH INTO MN AND WESTERN WI NON SUPERCELL TORNADO PARAMETER
IS INCREASING. SOMETHING TO KEEP AN EYE ON THERE...AN ISOLATED
FUNNEL CLOUD OR LANDSPOUT MAY BE POSSIBLE IF LAPSE RATES BECOME
STEEP ENOUGH IN THE AFTERNOON HOURS. OTHERWISE...THE OLD LOW WILL
PULL EAST SATURDAY NIGHT AND SUNDAY LEAVING THE REGION WITH COOLER
AIR FOR THE FIRST PART OF JUNE. THIS WILL KEEP THE AREA IN THE 60S
FOR HIGHS ON SUNDAY WITH MID 40S NORTH AND LOWER 50S SOUTH FOR LOWS
ON MONDAY MORNING. AS THE HIGH MOVES EAST...HIGHS WILL RESPOND INTO
THE LOWER 70S FOR MONDAY. MONDAY NIGHT WARM AIR ADVECTION AND MID
LEVEL MOISTURE BEGIN TO INCREASE AGAIN...RESULTING IN LATE
NIGHT/EARLY MORNING ELEVATED CONVECTION. TUESDAY LOOKS ACTIVE AS A
STRONGER WAVE ROTATES NORTHEAST INTO THE STATE. THIS WILL RESULT IN
MORE WIDESPREAD THUNDERSTORMS WITH RAINFALL AMOUNTS POSSIBLY
APPROACHING ONE INCH IN SOME PLACES. THIS WILL CERTAINLY KEEP SOIL
MOISTURE HIGH...AND ALSO RESULT IN RENEWED RIVER RISES. THE SYSTEM
WILL GRADUALLY EXIT THE REGION BY THURSDAY. THE LARGER SCALE FLOW
PATTERN REMAINS GENERALLY WESTERLY AT MID TO HIGH LEVELS. THIS
PROMOTES LEE SIDE TROUGHING AND WITH A CONTINUED SUB TROPICAL HIGH
ANCHORED OFF THE EAST COAST A WETTER THAN NORMAL PATTERN IS LIKELY
TO CONTINUE OVER THE NEXT 7 TO 10 DAYS. ANOTHER INTERESTING WRINKLE
IS A TROPICAL DISTURBANCE IN THE GULF OF MEXICO BY NEXT THUR/FRIDAY
WHICH MAY EVENTUALLY BE PULLED NORTH TOWARD THE MID MISSISSIPPI
RIVER VALLEY. HIGH TEMPERATURES OVER THE NEXT WEEK WILL LIKELY
REMAIN IN THE 70S ON AVERAGE AND NOT BREAK OUT OF A 65 TO 75 RANGE
BY TOO MUCH IF ANY. ANOTHER NOTE WITH OUR CURRENT WET WEATHER WILL
BE CLOUD COVER. UNLESS WE HAVE A STRONG HIGH AND STRONG
SUBSIDENCE...MOST LATE MORNINGS AND AFTERNOONS ON ANY SUNNY DAY WILL
GO SCT TO BKN BY AFTERNOON.
&&
.AVIATION...31/12Z
ISSUED AT 648 AM CDT THU MAY 30 2013
THERE WILL BE A COUPLE OF UPPER LEVEL DISTURBANCES AFFECTING TAF
LOCATIONS TODAY. THIS MORNING...MAINLY AFTER 15Z ONE DISTURBANCE
WILL MOVE ACROSS THE AREA MOVING SHOWERS AND THUNDERSTORMS FROM
NORTHERN MO INTO SOUTHEAST IA. THIS SHOULD MAINLY AFFECT KOTM BUT
COULD EXTEND COVERAGE TO KDSM AND KALO AS WELL. THIS AFTERNOON A
STRONGER DISTURBANCE WILL SHIFT ACROSS IOWA BETWEEN 21Z AND 05Z
BRINGING ANOTHER CHANCE FOR THUNDERSTORMS. THESE WOULD BE MORE
LIKELY TO PRODUCE HEAVY RAINFALL AS WELL AS STRONG WIND AND POSSIBLY
HAIL. IFR CONDITIONS ARE EXPECTED THROUGH 15-16Z THEN MVFR
CONDITIONS WITH STORMS OTHERWISE MOST LOCATIONS SHOULD BE VFR. SFC
WIND WILL BE SOUTHERLY AT 15-25KTS.
&&
.HYDROLOGY...
ISSUED AT 323 AM CDT FRI MAY 31 2013
A FLASH FLOOD WATCH REMAINS IN EFFECT FOR BUTLER COUNTY AT THIS
TIME DUE TO THE SMALL BREACH IN THE LEVEE ALONG THE BEAVER CREEK
AT NEW HARTFORD.
A WEATHER DISTURBANCE CAUSING AN AREA OF THUNDERSTORMS FROM KANSAS
AND MISSOURI WILL ROTATE NORTHEAST TODAY...AFFECTING THE SOUTHEAST
HALF OF THE FORECAST AREA LATER THIS MORNING THROUGH THE AFTERNOON
HOURS. THE SOUTHEAST MAY SEE UP TO AN INCH OR MORE OF RAIN...BUT
CURRENT FLASH FLOOD GUIDANCE HAS INCREASED TO 1.3 TO 1.5 INCHES
PER HOUR AND 1.5 TO 2.25 INCHES IN 3 HOURS AT PRESENT. UNLESS THE
STORMS BACK BUILD...THE RISK FOR ANY FLASH FLOODING REMAINS LOW
TODAY ACROSS OUR FORECAST AREA.
RIVER FLOOD WARNINGS REMAIN IN EFFECT FOR NUMEROUS LOCATIONS
THROUGHOUT THE HYDROLOGICAL SERVICES AREA FOR THE NEXT 5 TO 6 DAYS.
IN THE SHORT TERM... THE OLD H500 LOW WILL CYCLE EAST IN THE NEXT 24
TO 48 HOURS AND THEN DEPART. WITH ONLY LIGHT SHOWERS OR ISOLATED
THUNDER EXPECTED... RAINFALL WILL REMAIN LIGHT. FOLLOWING
THAT...HIGH PRESSURE WILL KEEP THE REGION RAIN FREE TO MONDAY
EVENING. THIS WILL SLOWLY ALLEVIATE THE SOME OF THE WATER ISSUES
THOUGH LARGER MAIN STEM RIVER SYSTEMS WILL REMAIN ABOVE FLOOD STAGE
THROUGH THE FORECAST PERIOD. ADDITIONAL MODERATE RAINFALL IS LIKELY
BEGINNING LATE MONDAY NIGHT THROUGH THURSDAY WHICH WILL NEED TO BE
WATCHED.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH THIS EVENING FOR BUTLER.
&&
$$
SHORT TERM...FAB
LONG TERM...REV
AVIATION...FAB
HYDROLOGY...REV
AREA FORECAST DISCUSSION
NWS DES MOINES IA
323 AM CDT FRI MAY 31 2013
.SHORT TERM.../TODAY /...
ISSUED AT 323 AM CDT FRI MAY 31 2013
THUNDERSTORMS HAVE DEVELOPED IN NORTHERN MISSOURI ALONG A ZONE OF
WARM AIR ADVECTION AND A LOW LEVEL JET. JUST NORTH OF THAT AREA BUT
STILL IN MO SOME WEAKER STORMS HAVE DEVELOPED AND ARE DISSIPATING.
THE STORMS HAVE AN EAST/NORTHEASTERLY TRACK AND WILL EVENTUALLY CLIP
FAR SOUTHERN IOWA. THE WEAKENING STORMS JUST ACROSS OUR BORDER WILL
LIKELY ONLY PRODUCE SOME SHOWERS ACROSS THE FAR SOUTH IN THE NEXT
FEW HOURS. A VORT MAX AND SHORT WAVE WILL PIVOT AROUND THE UPPER
LOW OVER THE EASTERN DAKOTAS AND THIS WILL SHIFT THE STORMS THAT ARE
A LITTLE FURTHER SOUTH IN NORTHERN MO RIGHT INTO SOUTHERN/SOUTHEAST
IOWA BY MID TO LATE MORNING THEN INTO EASTERN IOWA BY EARLY
AFTERNOON.
BY MID TO LATE AFTERNOON A STRONGER SHORT WAVE WILL PUSH INTO
WESTERN IOWA WHICH WILL BRING MORE THUNDERSTORMS TO THAT AREA AND
THIS WILL SHIFT EAST FROM 21Z INTO THE EVENING HOURS. THERE WILL BE
A TIME IN THE AFTERNOON WHERE SHOWERS AND STORMS WILL STILL BE OVER
EASTERN IOWA AND ADDITIONAL STORMS DEVELOPING OVER THE WEST WITH
CENTRAL IOWA DRY. LAPSE RATES OVER SOUTHERN IOWA AND ABOUT THE
SOUTHEAST THIRD OF THE STATE ARE PRETTY STEEP THIS AFTERNOON AND
THERE IS MORE THAN SUFFICIENT SHEAR FOR A FEW SEVERE STORMS. IN
ADDITION...HEAVY RAINFALL IS LIKELY WITH THE STORMS AS WELL...MAINLY
OVER THE FAR EAST AND SOUTHEAST.
YESTERDAY THE HI RES NMM EAST REALLY HAD THE PRECIP AREAS PEGGED AND
ALSO HAD DECENT TIMING OF THE PRECIP. I STILL LIKE WHAT THIS MODEL
DOES WITH THE PRECIP TODAY HOWEVER IT IS NOT PICKING UP THE MO
CONVECTION VERY WELL AT THIS TIME. IT IS ABOUT 3 HOURS LATER WITH
THAT SO I BLENDED NMM POPS WITH THE HRRR AND NAM12.
AS FOR TEMPS...THERE SHOULD BE SLIGHTLY WARMER AIR OVER THE SOUTH
AND SOUTHEAST TODAY SO I NUDGED HIGHS UP IN THESE AREAS. THE NORTH
SHOULD SEE TEMPS A FEW DEGREES WARMER AS WELL.
.LONG TERM.../TONIGHT THROUGH WEDNESDAY/...
ISSUED AT 323 AM CDT FRI MAY 31 2013
FEWER CONCERNS FOR THE NEXT SEVERAL DAYS AS UPPER TROUGH BEGINS TO
SWING EAST. ALREADY THE MAIN H850 MOISTURE CHANNEL HAS SHIFTED EAST
OF THE AREA WITH THE LINE OF STRONGER THUNDERSTORMS THAT EXITED THE
EASTERN PORTION OF THE FORECAST AREA EARLY THIS EVENING. HOWEVER
THERE WILL STILL BE SOME RESIDUAL CONVECTION FAR SOUTHEAST EARLY IN
THE PERIOD TONIGHT...ENDING QUICKLY AND MOVING EAST BY 06Z.
MEANWHILE...THE MAIN FEATURE YET LATE TONIGHT AND EARLY SATURDAY
WILL BE THE OLD H500 LOW WHICH IS LIKELY TO SPIN UP SOME SHOWERS AND
ISOLATED THUNDER AS IT MOVES ACROSS THE REGION TOMORROW AS THE COLD
POOL UNDERNEATH THE UPPER LEVEL LOW DROPS SOUTHEAST INTO THE REGION.
STEEP LAPSE RATES WILL BE IN THE AREA OF THE LOW ON SATURDAY AND
OVER THE NORTH INTO MN AND WESTERN WI NON SUPERCELL TORNADO PARAMETER
IS INCREASING. SOMETHING TO KEEP AN EYE ON THERE...AN ISOLATED
FUNNEL CLOUD OR LANDSPOUT MAY BE POSSIBLE IF LAPSE RATES BECOME
STEEP ENOUGH IN THE AFTERNOON HOURS. OTHERWISE...THE OLD LOW WILL
PULL EAST SATURDAY NIGHT AND SUNDAY LEAVING THE REGION WITH COOLER
AIR FOR THE FIRST PART OF JUNE. THIS WILL KEEP THE AREA IN THE 60S
FOR HIGHS ON SUNDAY WITH MID 40S NORTH AND LOWER 50S SOUTH FOR LOWS
ON MONDAY MORNING. AS THE HIGH MOVES EAST...HIGHS WILL RESPOND INTO
THE LOWER 70S FOR MONDAY. MONDAY NIGHT WARM AIR ADVECTION AND MID
LEVEL MOISTURE BEGIN TO INCREASE AGAIN...RESULTING IN LATE
NIGHT/EARLY MORNING ELEVATED CONVECTION. TUESDAY LOOKS ACTIVE AS A
STRONGER WAVE ROTATES NORTHEAST INTO THE STATE. THIS WILL RESULT IN
MORE WIDESPREAD THUNDERSTORMS WITH RAINFALL AMOUNTS POSSIBLY
APPROACHING ONE INCH IN SOME PLACES. THIS WILL CERTAINLY KEEP SOIL
MOISTURE HIGH...AND ALSO RESULT IN RENEWED RIVER RISES. THE SYSTEM
WILL GRADUALLY EXIT THE REGION BY THURSDAY. THE LARGER SCALE FLOW
PATTERN REMAINS GENERALLY WESTERLY AT MID TO HIGH LEVELS. THIS
PROMOTES LEE SIDE TROUGHING AND WITH A CONTINUED SUB TROPICAL HIGH
ANCHORED OFF THE EAST COAST A WETTER THAN NORMAL PATTERN IS LIKELY
TO CONTINUE OVER THE NEXT 7 TO 10 DAYS. ANOTHER INTERESTING WRINKLE
IS A TROPICAL DISTURBANCE IN THE GULF OF MEXICO BY NEXT THUR/FRIDAY
WHICH MAY EVENTUALLY BE PULLED NORTH TOWARD THE MID MISSISSIPPI
RIVER VALLEY. HIGH TEMPERATURES OVER THE NEXT WEEK WILL LIKELY
REMAIN IN THE 70S ON AVERAGE AND NOT BREAK OUT OF A 65 TO 75 RANGE
BY TOO MUCH IF ANY. ANOTHER NOTE WITH OUR CURRENT WET WEATHER WILL
BE CLOUD COVER. UNLESS WE HAVE A STRONG HIGH AND STRONG
SUBSIDENCE...MOST LATE MORNINGS AND AFTERNOONS ON ANY SUNNY DAY WILL
GO SCT TO BKN BY AFTERNOON.
&&
.AVIATION...31/06Z
ISSUED AT 1155 PM CDT THU MAY 30 2013
VFR CONDITIONS EXPECTED THROUGHOUT THE TAF PERIOD FOR ALL TAF
SITES. HOWEVER...CONVECTION LOOKS TO DEVELOP FRIDAY MORNING AND
WILL POSSIBLY AFFECT OTM PAST 15Z FRIDAY. LOW CONFIDENCE WITH
TIMING AND WITH MENTION OF MVFR OR LESS CIGS/VIS. HAVE MENTION OF
THUNDER FRIDAY. OTHERWISE...DECENT MIXING BEHIND TROUGH THAT IS
EXPECTED TO MOVE THROUGH FRIDAY MORNING. VERY SMALL CHANCE DSM
WILL SEE SOME RAIN/THUNDER THROUGH 07Z FRIDAY AND SO ONLY HAVE
VCTS MENTIONED ATTM.
&&
.HYDROLOGY...
ISSUED AT 323 AM CDT FRI MAY 31 2013
A FLASH FLOOD WATCH REMAINS IN EFFECT FOR BUTLER COUNTY AT THIS
TIME DUE TO THE SMALL BREACH IN THE LEVEE ALONG THE BEAVER CREEK
AT NEW HARTFORD.
A WEATHER DISTURBANCE CAUSING AN AREA OF THUNDERSTORMS FROM KANSAS
AND MISSOURI WILL ROTATE NORTHEAST TODAY...AFFECTING THE SOUTHEAST
HALF OF THE FORECAST AREA LATER THIS MORNING THROUGH THE AFTERNOON
HOURS. THE SOUTHEAST MAY SEE UP TO AN INCH OR MORE OF RAIN...BUT
CURRENT FLASH FLOOD GUIDANCE HAS INCREASED TO 1.3 TO 1.5 INCHES
PER HOUR AND 1.5 TO 2.25 INCHES IN 3 HOURS AT PRESENT. UNLESS THE
STORMS BACK BUILD...THE RISK FOR ANY FLASH FLOODING REMAINS LOW
TODAY ACROSS OUR FORECAST AREA.
RIVER FLOOD WARNINGS REMAIN IN EFFECT FOR NUMEROUS LOCATIONS THROUGHOUT
THE HYDROLOGICAL SERVICES AREA FOR THE NEXT 5 TO 6 DAYS. IN THE
SHORT TERM... THE OLD H500 LOW WILL CYCLE EAST IN THE NEXT 24 TO
48 HOURS AND THEN DEPART. WITH ONLY LIGHT SHOWERS OR ISOLATED
THUNDER EXPECTED... RAINFALL WILL REMAIN LIGHT. FOLLOWING
THAT...HIGH PRESSURE WILL KEEP THE REGION RAIN FREE TO MONDAY EVENING.
THIS WILL SLOWLY ALLEVIATE THE SOME OF THE WATER ISSUES THOUGH
LARGER MAIN STEM RIVER SYSTEMS WILL REMAIN ABOVE FLOOD STAGE THROUGH
THE FORECAST PERIOD. ADDTIONAL MODERATE RAINFALL IS LIKELY BEGINNING
LATE MONDAY NIGHT THROUGH THURSDAY WHICH WILL NEED TO BE WATCHED.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH THIS EVENING FOR BUTLER.
&&
$$
SHORT TERM...BOKSA
LONG TERM...REV
AVIATION...PODRAZIK
HYDROLOGY...REV
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1159 PM CDT THU MAY 30 2013
...UPDATED AVIATION DISCUSSION...
.SHORT TERM.../TONIGHT /...
ISSUED AT 350 PM CDT THU MAY 30 2013
MAIN SHORTWAVE LIFTING THROUGH THE BASE OF THE UPPER LEVEL TROUGH
RESPONSIBLE FOR AREA OF SHOWERS AND THUNDERSTORMS ACROSS THE FAR
SOUTHEASTERN CWA. AS SHORTWAVE CONTINUES TO LIFT NORTHEAST THROUGH
THE EASTERN PORTION OF THE STATE...AREA OF SHOWERS/THUNDERSTORMS
WILL CONTINUE TO SHOVE EAST OUT OF THE CWA. LOOKING BACK TO THE
WEST...HAVE SOME ISOLATED WEAK CELLS DEVELOPING ACROSS CENTRAL
NE/KS. THIS ACTIVITY MAY APPROACH THE SOUTHWESTERN/SOUTHERN CWA BY
MID EVENING...BUT IS EXPECTED TO BE RELATIVELY WEAK WITH LESS THAN
1000 J/KG CAPE ON NAM/RAP SOUNDINGS. HRRR SEEMS TO BE GRASPING
CURRENT RADAR TRENDS CORRECTLY...SO KEPT POPS CLOSE TO THE HRRR
OUTPUT. THE WESTERN ACTIVITY IS MOSTLY DIURNALLY DRIVEN...SO EXPECT
IT TO DIMINISH TOWARD SUNSET. ANOTHER WAVE OF ENERGY TO ROUND THE
BASE OF THE UPPER LEVEL TROUGH TO APPROACH THE STATE LATE
TONIGHT...MAY ALLOW FOR SOME SHOWERS AND ISOLATED THUNDERSTORMS TO
DEVELOP TOWARD SUNRISE FRIDAY MORNING. THE DEEP MOISTURE THAT HAS
BEEN IN PLACE ACROSS THE STATE OVER THE PAST WEEK...IS BEGINNING TO
PUSH EAST WITH THE ADVANCEMENT OF A DRY LINE OVER CENTRAL
NE/KS...THEREFORE THE HEAVY RAIN THREAT WILL BE LESSENED WITH ANY
ACTIVITY THAT DEVELOPS LATE TONIGHT/EARLY FRIDAY MORNING.
.LONG TERM.../FRIDAY THROUGH THURSDAY/...
ISSUED AT 350 PM CDT THU MAY 30 2013
AN UPPER LEVEL LOW PRESSURE SYSTEM WILL REMAIN NEARLY STATIONARY
OVER THE DAKOTAS AND MINNESOTA FRIDAY AND FRIDAY NIGHT...BEFORE
MOVING EASTWARD ACROSS IOWA ON SATURDAY AND AWAY OVER THE GREAT
LAKES ON SATURDAY NIGHT. ON FRIDAY MORNING LOW LEVEL FLOW WILL
STILL BE FROM THE SOUTH SOUTHWEST AND AN APPROACHING SHORTWAVE
MOVING AROUND THE UPPER LOW SHOULD KICK OFF THUNDERSTORMS ACROSS
EASTERN KANSAS LATE TONIGHT THAT WILL MOVE ACROSS OUR SOUTHERN AND
EASTERN COUNTIES ON FRIDAY. HAVE INCREASED POPS INTO THE 70 TO 80
PERCENT RANGE IN OUR SOUTHEAST TO ACCOUNT FOR THIS...AND SEVERE
WEATHER WILL BE POSSIBLE IN THESE AREAS AS WELL. FRIDAY SHOULD BE
FAIRLY WARM ESPECIALLY IF SKIES ARE ABLE TO CLEAR ACROSS MUCH OF
THE CWA...AND HAVE RAISED FORECAST HIGHS A BIT EVEN INTO THE
LOWER 80S IN SOME AREAS.
BY FRIDAY EVENING THE DAYTIME STORMS WILL BE EXITING TO THE EAST
AHEAD OF A SURFACE TROUGH MOVING ACROSS THE AREA. WINDS BEHIND
THIS TROUGH WILL TURN TO WEST AND THEN NORTHWEST WITH COOLER AIR
FLOWING INTO THE AREA. IN ADDITION...AS THE UPPER LEVEL LOW
PRESSURE TROUGH MOVES ACROSS OUR AREA ON SATURDAY IT WILL BE
ACCOMPANIED BY THICK CLOUDS AND LIGHT SHOWERS MAKING FOR A GREY
AND DAMP DAY. NO THUNDERSTORMS ARE ANTICIPATED AND ANY RAINFALL
AMOUNTS WILL BE LIGHT. COVERAGE IS UNCERTAIN SO HAVE MAINTAINED
POPS BELOW 50 PERCENT...BUT THIS MAY NEED TO BE INCREASED LATER IN
A CLASSIC HIGH POP/LOW QPF SCENARIO. BY SUNDAY A SURFACE RIDGE
WILL BUILD IN MAKING FOR MOSTLY CLEAR AND DRY BUT COOL WEATHER
WITH LIGHT NORTH WINDS.
FROM SUNDAY NIGHT THROUGH THURSDAY THE 500 MB PATTERN WILL UNDERGO
AN EERILY SIMILAR EVOLUTION TO WHAT WE HAVE SEEN OVER THE LAST
SEVERAL DAYS...AS ANOTHER UPPER LOW MOVES INTO THE NORTHWESTERN
U.S. AND THEN ACROSS THE UPPER MIDWEST. THIS WILL RESULT IN
ANOTHER EXTENDED PERIOD OF THUNDERSTORM CHANCES FOR OUR AREA FROM
MONDAY NIGHT THROUGH THE END OF THE FORECAST PERIOD.
HOWEVER...UNLIKE THE SYSTEM OF THE PAST SEVERAL DAYS...THE 500 MB
LOW NEXT WEEK WILL NOT HAVE AS MUCH LATITUDINAL EXTENT AND WILL BE
GENERALLY MORE PROGRESSIVE...MITIGATING SOMEWHAT THE POTENTIAL FOR
EXTENDED HEAVY RAINFALL. THE DETAILS OF THE RAINFALL FORECAST FOR
NEXT WEEK WILL BE IRONED OUT LATER...BUT AT LEAST THERE WILL BE
SEVERAL RELATIVELY DRY DAYS THIS WEEKEND TO ALLOW CURRENT FLOOD
WATERS TO SUBSIDE...AND RAINFALL AMOUNTS NEXT WEEK SHOULD BE
CONSIDERABLY LIGHTER IN MOST AREAS WITH THE PRIMARY CHANCES
LIMITED TO THE MONDAY NIGHT...TUESDAY...AND TUESDAY NIGHT PERIODS.
&&
.AVIATION...31/06Z
ISSUED AT 1155 PM CDT THU MAY 30 2013
VFR CONDITIONS EXPECTED THROUGHOUT THE TAF PERIOD FOR ALL TAF
SITES. HOWEVER...CONVECTION LOOKS TO DEVELOP FRIDAY MORNING AND
WILL POSSIBLY AFFECT OTM PAST 15Z FRIDAY. LOW CONFIDENCE WITH
TIMING AND WITH MENTION OF MVFR OR LESS CIGS/VIS. HAVE MENTION OF
THUNDER FRIDAY. OTHERWISE...DECENT MIXING BEHIND TROUGH THAT IS
EXPECTED TO MOVE THROUGH FRIDAY MORNING. VERY SMALL CHANCE DSM
WILL SEE SOME RAIN/THUNDER THROUGH 07Z FRIDAY AND SO ONLY HAVE
VCTS MENTIONED ATTM.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH FRIDAY EVENING FOR BUTLER.
&&
$$
SHORT TERM...BEERENDS
LONG TERM...LEE
AVIATION...PODRAZIK
AREA FORECAST DISCUSSION
NWS GOODLAND KS
207 PM MDT FRI MAY 31 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 152 PM MDT FRI MAY 31 2013
EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOW LARGE SCALE
TROUGH STILL IN PLACE ACROSS NORTHERN PLAINS WITH CLOSED CENTER
OVER THE EASTERN DAKOTAS. A SERIES OF WEAK VORTICITY MAXIMA ARE
ROTATING AROUND THE WESTERN EXTENT OF THE UPPER LOW PRODUCING
MID-HIGH CLOUDS ACROSS THE PLAINS. OVER THE SOUTHERN PART OF OUR CWA
STEEP LAPSE RATES ALONG A BAROCLINIC ZONE HAS LED TO DEVELOPMENT OF
HIGH BASED SHOWERS/VIRGA. WITH BASES GENERALLY AROUND 12KFT AND A
DEEP DRY LAYER BELOW THIS...IT IS UNLIKELY MUCH MORE THAN A FEW
SPRINKLES WILL REACH THE SURFACE WITH THIS ACTIVITY.
RED FLAG CONDITIONS AND GUSTY WINDS SHOULD CONTINUE THROUGH THE EARLY
EVENING PERIOD ACROSS NW HALF OF THE CWA. LIMITING FACTOR FOR RFW
CONTINUES TO BE FUELS...AND WITHOUT FURTHER INFORMATION IN THIS
REGARD I DECIDED AGAINST EXPANDING CURRENT WARNING. WINDS HAVE
OCCASIONALLY HIT ADVISORY CRITERIA IN THE NW...HOWEVER THESE
CONDITIONS HAVE BEEN SPORADIC...SO IVE LEANED AGAINST ISSUANCE OF
WIND ADVISORY.
TONIGHT A SHORTWAVE TROUGH WILL ROUND THE BASE OF THE LARGE SCALE
UPPER LOW WITH A COLD FRONT DROPPING SOUTH OVER OUR CWA (06 TO 09Z).
WHILE WINDS MAY DECREASE SOME AFTER SUNSET...THE LULL IN WINDS THIS
EVENING WILL BE SHORT LIVED BEFORE NEAR ADVISORY LEVEL WINDS
REDEVELOP AFTER MIDNIGHT AND CONTINUE THROUGH THE DAY SATURDAY
BEHIND THE FROPA. SOME GUIDANCE IS ALSO SHOWING BETTER MID LEVEL
MOISTURE WITH THIS UPPER LEVEL TROUGH ROTATING INTO THE
CWA...HOWEVER THE BEST LIFT IS OUTSIDE OUR CWA...AND MODELS NEVER
INITIATE SHOWERS OVER OUR CWA WITH DRY LOW LEVELS STILL IN PLACE.
OTHER THAN THICKENING CLOUD COVER...I AM NOT EXPECTING ANY PRECIP.
OVERNIGHT LOWS TONIGHT WILL DROP TO THE LOW 40S IN EASTERN COLORADO
TO THE LOW 50S IN NORTH CENTRAL KANSAS. CONSIDERING THE COOL NATURE
OF THE AIR MASS WE WOULD BE LOOKING AT MUCH COLDER TEMPS IF IT WASNT
FOR CLOUD COVER AND WINDS OVERNIGHT. HIGHS ON SATURDAY MAY STRUGGLE
TO REACH THE UPPER 60S/70F IF CLOUD COVER FAILS TO CLEAR BY THE
AFTERNOON AS CURRENTLY ADVERTISED.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 152 PM MDT FRI MAY 31 2013
FOR SATURDAY NIGHT THROUGH SUNDAY NIGHT...THE UPPER LEVEL RIDGE WILL
BEGIN TO MOVE OVER THE AREA SATURDAY NIGHT AS A SURFACE HIGH MOVES
INTO THE AREA. SUNDAY THE SURFACE HIGH WILL SLIDE EAST. AS IT DOES
SO A TIGHT PRESSURE GRADIENT WILL DEVELOP OVER THE AREA FROM WEST TO
EAST BEHIND THE EXITING SURFACE HIGH. WINDS WILL BREEZY BUT WILL
DECLINE BEFORE SUNSET AS TEMPERATURES COOL. SUNDAY EVENING AS THE UPPER
LEVEL RIDGE AXIS MOVES EAST OF THE AREA A SHORT WAVE TROUGH WILL
MOVE ACROSS THE AREA. POINT SOUNDINGS SHOW A VERY SMALL AMOUNT OF
ELEVATED INSTABILITY OVER THE SOUTHWEST PART OF THE AREA AS THE
SHORT WAVE MOVES THROUGH. AT THIS TIME WILL KEEP THE FORECAST DRY DUE
TO LOW CONFIDENCE THAT ANY STORMS WILL DEVELOP GIVEN THE ELEVATED
CAPE IS LESS THAN 200 J/KG...AND THE DEEP DRY LAYER EXTENDING UP TO
600MB OR SO WHICH WILL CAUSE ANY LIGHT RAIN THAT MAY DEVELOP TO
EVAPORATE.
MONDAY THROUGH FRIDAY AN UPPER LEVEL TROUGH WILL MOVE ACROSS THE
NORTHERN PLAINS. MODELS HAVE SHIFTED THE TRACK OF THE TROUGH
SLIGHTLY NORTH...BUT OVERALL THIS SEEMS TO HAVE LITTLE EFFECT ON
PRECIP. CHANCES FOR THE PERIOD. NUMEROUS SHORT WAVE TROUGHS THAT
EXTEND FROM THE MAIN FEATURE MOVE OVER THE AREA TROUGH THE PERIOD AS
THE TROUGH SLOWLY MOVES EAST OVER THE NORTHERN PLAINS. WITH EACH
SHORT WAVE TROUGH MOVING THROUGH THE AREA PRECIP. CHANCES WILL
RETURN.
TEMPERATURES FOR THE PERIOD WILL START OUT 10 DEGREES ABOVE NORMAL
MONDAY THEN COOL TO NEAR NORMAL TUESDAY THROUGH FRIDAY AS A COLD
FRONT MOVES THROUGH THE AREA SOMETIME ON TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1120 AM MDT FRI MAY 31 2013
VFR CONDITIONS EXPECTED TO PREVAIL THROUGH THE TAF PERIOD AT BOTH
KGLD AND KMCK. WESTERLY WINDS GUSTING 35-39KT WILL DECREASE SOME
AFTER SUNRISE...WITH SUSTAINED WINDS 10-15KT THIS EVENING. WINDS
WILL INCREASE LATE TONIGHT (BY 09-10Z) AS A COLD FRONT MOVES
ACROSS THE REGION AND CONTINUE THROUGH SATURDAY MORNING. FOR NOW I
INCLUDED GUSTS 30-33KT...HOWEVER THERE IS INDICATION THAT WINDS
COULD BE STRONGER FOR A BRIEF PERIOD IMMEDIATELY BEHIND THE FRONT.
THERE COULD ALSO BE A FEW LIGHT SHOWERS AS THE FRONT MOVES ACROSS
THE AREA...HOWEVER WITH DEEP DRY LAYER IN PLACE IM NOT SURE IF
THERE WILL BE MUCH MORE THAN VIRGA WITHIN THE VICINITY OF EITHER
TERMINAL.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR KSZ013-027.
CO...RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ252>254.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JTL
AVIATION...DR
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1207 AM CDT FRI MAY 31 2013
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 343 PM CDT THU MAY 30 2013
WATER VAPOR LOOP SHOWING CONVECTIVE SYSTEM OVER WESTERN MO MOVING
SLOWLY EWD AHEAD OF ONE MID-LEVEL TROUGH. HOWEVER...THERE IS A VERY
SHORT WAVELENGTH BETWEEN THAT TROUGH AND THE FOLLOWING IMPULSE THAT
APPEARS TO BE OVER WRN KS AT MID AFTERNOON. SCATTERED SHOWERS AND
THUNDERSTORMS HAVE FIRED OVER WRN KS AHEAD OF THIS FEATURE AND THEY
ARE MOVING EWD. SHORT RANGE MODEL GUIDANCE NOT RESOLVING THE
DETAILS OF THIS VERY WELL...HOWEVER THE 17Z HRRR DOES NOW HAVE A
LINE OF CONVECTION MOVING INTO CENTRAL KS BY 21Z. IT FORECASTS THIS
TO BREAK UP WITH THE REMNANTS MOVING ACROSS NORTHEAST KS DURING THE
EVENING...AND THEN ANOTHER SMALL CONVECTIVE SYSTEM MOVES SOUTHEAST
OUT OF NEBRASKA INTO NORTHEAST KS LATER TONIGHT. DO NOT HAVE HIGH
CONFIDENCE IN THIS SCENARIO...ALTHOUGH SOME TYPE OF SMALL MCS WOULD
APPEAR TO BE LIKELY IN CENTRAL/NORTHEAST KS LATER TONIGHT. THIS
POSSIBLE SYSTEM WOULD APPEAR TO MOVE THROUGH FAST ENOUGH AS TO NOT
CAUSE SIG PROBLEMS WITH HEAVY RAIN/FLOODING. EARLIER CONCERNS ABOUT
WARM AIR ADVECTION CAUSING LIFT AND THUNDERSTORM AREA WITH
POTENTIALLY HEAVY RAINFALL OVER EC KS TONIGHT ARE LESSENING AS
CONVECTIVE BOUNDARY SAGS WAY SOUTH INTO NORTHEAST OKLAHOMA.
THUS...HAVE CANCELLED FLASH FLOOD WATCH THAT WAS IN EFFECT FOR THIS
AFTERNOON...AND AM NOT PLANNING ON GOING OUT WITH A NEW ONE AT THIS
TIME. CONFIDENCE IN THE DETAILS OF PRECIPITATION EVOLUTION TONIGHT
IS NOT HIGH.
ON FRIDAY...FRONTAL BOUNDARY SHOULD MAKE IT FAR ENOUGH SOUTH BY
AFTERNOON THAT THE MAIN CHANCE OF THUNDERSTORM ACTIVITY WOULD BE IN
EC KS...MAINLY SOUTHEAST OF THE KANSAS TURNPIKE. LOWS TONIGHT
EXPECTED TO BE AROUND 60 OVER NC KS AND IN THE MID 60S EC. HIGHS ON
FRIDAY ARE FORECAST TO MAX OUT AROUND 80.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 343 PM CDT THU MAY 30 2013
DETAILS ONLY GET MURKIER FOR FRIDAY EVENING...BUT AT LEAST SOME
CHANCE SHOULD EXIST AHEAD OF THE SYNOPTIC BOUNDARY FOR SOUTHERN AND
EASTERN LOCATIONS. SUFFICIENT SHEAR AND INSTABILITY WOULD SUPPORT A
SEVERE CONCERN THROUGH THIS TIME AS WELL..BUT THE SOUTHEASTWARD
SHIFTING UPPER LOW SHOULD PUSH THE EFFECTIVE FRONT SOUTH OF THE AREA
BY DAWN. COLD AIR ADVECTION SETS IN FOR SATURDAY ON NORTHWEST
BREEZES WITH SOME STRATUS/STRATOCU DEVELOPING BY MID AFTERNOON.
WEAKENING WINDS AND CLEARING SKIES SPELL A COOL NIGHT SATURDAY
NIGHT. SURFACE RIDGE SETS UP FOR SUNDAY WITH LITTLE IF ANY
MODERATION TO HIGHS.
GULF MOISTURE DOES NOT GET COMPLETELY SCOURED OUT...AND BY LATE
MONDAY SOUTH WINDS AHEAD OF AN APPROACHING NORTHERN ROCKIES CYCLONE
WILL BRING THUNDERSTORM CHANCES BACK. BEST CHANCES LOOK TO BE
TUESDAY INTO TUESDAY NIGHT WITH GOOD MODEL AGREEMENT ON A MID LEVEL
WAVE PASSING. TEMPS SHOULD GENERALLY BE NEAR EARLY JUNE NORMALS SAVE
ANY DAYTIME MCS ACTIVITY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1132 PM CDT THU MAY 30 2013
THUNDERSTORMS CONTINUE TO DEVELOP ALONG THE I 70 CORRIDOR AND SHOULD
PERSIST THROUGH 09Z IN THE TERMINALS BEFORE DECREASING/ENDING FROM WEST
TO EAST IN THE 08-11Z TIMEFRAME. EXPECT TEMPS MVFR CIGS AND VSBYS
IN THE STRONGER ELEVATED CONVECTIVE CELLS BEFORE DIMINISHING AND
ENDING BEFORE SUNRISE. BEYOND 11Z VFR CONDITIONS WILL BE THE
RULE...ALTHOUGH A FEW SHOWERS MAY LINGER INITIALLY. SFC WINDS WILL
GRADUALLY VEER THROUGH THE DAY...BUT REMAIN FAIRLY LIGHT SOUTHWEST
TO WEST.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...60
LONG TERM...65
AVIATION...63
AREA FORECAST DISCUSSION
NWS JACKSON KY
601 PM EDT FRI MAY 31 2013
.UPDATE...
ISSUED AT 600 PM EDT FRI MAY 31 2013
BASED ON CURRENT RADAR WENT AHEAD AND INCREASED POPS FOR NORTHWESTERN
COUNTIES IN THE AERA...WITH THE POTENTIAL FOR SOME SCATTERED SHOWERS
OVER THE NEXT HOUR OR TWO ALONG THE FAR SOUTHWESTERN COUNTIES AS
WELL. THAT BEING SAID...LOOKING AT MODEL PARAMETERS...DYNAMICS SEEM TO BE
FAIRLY WEAK OVER MUCH OF EASTERN KY...AND HI RES MODEL /HRRR/ PRECIP
SHOWS A QUICK DIMINISHING TREND THROUGHOUT THE EVENING. TRIED TO
REFLECT THIS IDEA WITHIN THE POPS AND WX...WITH THE BEST CHANCE FOR
CONVECTION REMAINING OVER THE NORTHERN COUNTIES THROUGH THE EVENING.
BUT WITH VERY LITTLE LIGHTNING SHOWING UP ON RADAR AND WEAK
INSTABILITY IN OUR AREA...ONLY SLIGHT CHANCE OF THUNDER WAS
WARRANTED.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 320 PM EDT FRI MAY 31 2013
MESOSCALE CONVECTIVE VORTEX WHICH HAD BEEN NEAR MADISONVILLE KY AT
1230 PM HAS PULLED NORTHEAST AND IS NOW NEAR LOUISVILLE. STRONGEST
CONVECTION HAS BEEN OCCURRING AHEAD OF THIS FEATURE AND NOW PULLING
INTO SOUTHWEST OH. CONVECTION TRAILS SOUTH TO WEST OF LAKE CUMBERLAND
ALONG OLD OUTFLOW BOUNDARY. WITH THE MOVEMENT OF THIS CONVECTION NNE
IT HAS ONLY BEEN VERY SLOWLY NEARING THE SW PART OF FORECAST AREA.
HOWEVER...OUTFLOW FROM THIS COULD STILL SERVE AS TRIGGER FOR
CONVECTION OVER THE FAR WEST PART OF FORECAST AREA. THE HRRR HAS BEEN
PERSISTENT IN TRYING TO BRING CONVECTION INTO OUR AREA...WITH THE 17Z
RUN TRYING TO MOVE CONVECTION INTO THE AREA AFTER 22Z...AND THEN SLOWLY
DISSIPATING AS IT MOVES EAST. WITH THE MCV MOVING AWAY AND WITH LOSS
OF DAYTIME HEATING DO EXPECT ANY CONVECTION IN OUR AREA TO DECREASE
QUICKLY THIS EVENING AND WILL DROP SHOWERS AND THUNDERSTORMS FROM
FORECAST AFTER MIDNIGHT.
A SHORT WAVE MOVING OUT OF THE SOUTHERN PLAINS SHOULD TRIGGER MORE
CONVECTION OVER MO TONIGHT...WITH THE EFFECTS OF THIS REMAINING TO
OUR WEST OVERNIGHT INTO SATURDAY MORNING. SATURDAY WILL BRING A
CHANCE FOR MORE SHOWERS AND THUNDERSTORMS WITH ANY OUTFLOW
BOUNDARIES FROM OVERNIGHT CONVECTION TO OUR WEST POSSIBLY SERVING AS
TRIGGER FOR MAINLY AFTERNOON SHOWERS AND THUNDERSTORMS ON SATURDAY.
IT IS STILL POSSIBLE SOME OF THE STORMS SATURDAY AFTERNOON AND
EVENING COULD BECOME SEVERE...WITH GREATER INSTABILITY DURING THE
AFTERNOON INTO THE EVENING.
MODELS HAVE TRENDED TOWARDS A QUICKER SOLUTION WITH CONVECTION AHEAD
OF THE COLD FRONT MOVING INTO THE AREA SATURDAY NIGHT. WE HAVE
FOLLOWED THIS IDEA WITH LIKELY SHOWER AND THUNDERSTORM PROBABILITIES
AREA WIDE FOR SATURDAY NIGHT.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 320 PM EDT FRI MAY 31 2013
A COLD FRONT SHOULD BE ABOUT READY TO ENTER THE FORECAST AREA FROM
THE NW AT THE START OF THE PERIOD...WITH SUPPORT FROM AN APPROACHING
UPPER TROUGH...AND A RIBBON OF HIGHER DEW POINTS OFF THE GULF ALONG
THE FRONT BEING ADVECTED ALONG BY A 30-40 KT LOW LEVEL FLOW JUST OFF
THE SURFACE. ALL THIS CONSIDERED...THERE WILL LIKELY BE AN ONGOING
CONVECTIVE EVENT...WITH MODELS SHOWING THE GREATEST LIKELIHOOD OF
THIS IN THE SE PART OF THE AREA. AS THE FRONT SLOWLY PUSHES INTO AND
THROUGH THE FORECAST AREA SUNDAY AND SUNDAY EVENING...THERE COULD
ALSO BE ADDITIONAL DEVELOPMENT...WITH THE GREATEST OPPORTUNITY FOR
THIS IN THE SE WHERE FROPA WILL OCCUR LAST. THE LAST OF ANY
LINGERING PRECIP SHOULD END SUNDAY NIGHT OR EARLY MONDAY AS THE
FRONT CONTINUES ON TO OUR SE.
HIGH PRESSURE OVER THE MIDWEST WILL SUPPLY NOTICEABLY DRIER AND
SOMEWHAT COOLER AIR EARLY IN THE WEEK UNDER WNW FLOW ALOFT. RIDGING
ALOFT WILL PASS OVER ON TUESDAY INTO WEDNESDAY...WITH THE SURFACE
HIGH SHIFTING EASTWARD. THIS WILL BRING A CONTINUATION OF DRY
WEATHER...BUT WITH WARMING ALREADY OCCURRING AND AN EVENTUAL
INCREASE IN SURFACE MOISTURE.
AFTER THIS...MODEL DIFFERENCES BETWEEN THE GFS AND ECMWF BECOME MORE
APPARENT LATE IN THE WEEK. THE ECMWF DEVELOPS AN UPPER RIDGE OVER
THE CAROLINAS...BUT THIS FEATURE IS LACKING IN THE OPERATIONAL GFS.
ALL MODELS INDICATE AN UPPER LOW HEADING EAST ALONG THE CANADIAN
BORDER AND INTO ONTARIO...WITH A SOUTHWARD EXTENDING TROUGH. THE 00Z
ECMWF DOES NOT ALLOW AS MUCH OF A SOUTHERN EXTENSION OF THIS TROUGH
DUE TO ITS CAROLINA RIDGE. THE RESULT IS THAT THE GFS DEVELOPS
CONVECTION OVER THE LOCAL AREA FROM WEDNESDAY ON. MEANWHILE...THE
ECMWF SHOWS LIGHT PRECIP ONLY ON THURSDAY AS THE TROUGH SCOOTS BY TO
OUR NORTH. THE GEM AND GFS ENSEMBLE MEAN SUPPORT THE OPERATIONAL
GFS...AND PREFER TO WEIGHT THE FORECAST TOWARD IT...WITH JUST A BIT
OF ECMWF INFLUENCE TO KNOCK THE POPS DOWN SLIGHTLY FROM WHERE THEY
WOULD OTHERWISE BE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 121 PM EDT FRI MAY 31 2013
CONVECTION IS CURRENTLY DEVELOPING ACROSS CENTRAL KY AND EXPECT
SCATTERED SHOWERS AND THUNDERSTORMS TO MOVE INTO THE WESTERN PART OF
THE FORECAST AREA BY MID TO LATE AFTERNOON. CURRENT INDICATIONS ARE
THAT ANY CONVECTION THAT MOVES INTO OR DEVELOPS OVER EASTERN KY WILL
DECREASE QUICKLY EARLY THIS EVENING. THERE IS CONSIDERABLE
UNCERTAINTY HOW FAR EAST ANY SHOWERS OR THUNDERSTORMS WILL
OCCUR...AND AT THIS TIME WILL NOT MENTION ANY THUNDER IN THE JKL OR
LOZ TAF. WILL GO WITH VCTS IN THE SME TAF. OUTSIDE OF ANY SHOWER OR
THUNDERSTORMS VFR CONDITIONS WILL PREVAIL FOR THE REMAINDER OF THE
DAY. ALSO EXPECT VFR CONDITIONS TO PREVAIL TONIGHT AS WELL. THE
EXCEPTION TO THIS WOULD BE ANY AREAS THAT RECEIVE RAIN TODAY WHERE
OVERNIGHT FOG WOULD BE POSSIBLE. VFR WILL PREVAIL AGAIN SATURDAY
MORNING...WITH SHOWERS AND THUNDERSTORMS AGAIN POSSIBLE SATURDAY
AFTERNOON. AN APPROACHING COLD FRONT WILL BRING WIDESPREAD SHOWERS
AND THUNDERSTORMS SATURDAY NIGHT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JMW
SHORT TERM...SBH
LONG TERM...HAL
AVIATION...SBH
AREA FORECAST DISCUSSION
NWS JACKSON KY
320 PM EDT FRI MAY 31 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 320 PM EDT FRI MAY 31 2013
MESOSCALE CONVECTIVE VORTEX WHICH HAD BEEN NEAR MADISONVILLE KY AT
1230 PM HAS PULLED NORTHEAST AND IS NOW NEAR LOUISVILLE. STRONGEST
CONVECTION HAS BEEN OCCURRING AHEAD OF THIS FEATURE AND NOW PULLING
INTO SOUTHWEST OH. CONVECTION TRAILS SOUTH TO WEST OF LAKE CUMBERLAND
ALONG OLD OUTFLOW BOUNDARY. WITH THE MOVEMENT OF THIS CONVECTION NNE
IT HAS ONLY BEEN VERY SLOWLY NEARING THE SW PART OF FORECAST AREA.
HOWEVER...OUTFLOW FROM THIS COULD STILL SERVE AS TRIGGER FOR
CONVECTION OVER THE FAR WEST PART OF FORECAST AREA. THE HRRR HAS BEEN
PERSISTENT IN TRYING TO BRING CONVECTION INTO OUR AREA...WITH THE 17Z
RUN TRYING TO MOVE CONVECTION INTO THE AREA AFTER 22Z...AND THEN SLOWLY
DISSIPATING AS IT MOVES EAST. WITH THE MCV MOVING AWAY AND WITH LOSS
OF DAYTIME HEATING DO EXPECT ANY CONVECTION IN OUR AREA TO DECREASE
QUICKLY THIS EVENING AND WILL DROP SHOWERS AND THUNDERSTORMS FROM
FORECAST AFTER MIDNIGHT.
A SHORT WAVE MOVING OUT OF THE SOUTHERN PLAINS SHOULD TRIGGER MORE
CONVECTION OVER MO TONIGHT...WITH THE EFFECTS OF THIS REMAINING TO
OUR WEST OVERNIGHT INTO SATURDAY MORNING. SATURDAY WILL BRING A
CHANCE FOR MORE SHOWERS AND THUNDERSTORMS WITH ANY OUTFLOW
BOUNDARIES FROM OVERNIGHT CONVECTION TO OUR WEST POSSIBLY SERVING AS
TRIGGER FOR MAINLY AFTERNOON SHOWERS AND THUNDERSTORMS ON SATURDAY.
IT IS STILL POSSIBLE SOME OF THE STORMS SATURDAY AFTERNOON AND
EVENING COULD BECOME SEVERE...WITH GREATER INSTABILITY DURING THE
AFTERNOON INTO THE EVENING.
MODELS HAVE TRENDED TOWARDS A QUICKER SOLUTION WITH CONVECTION AHEAD
OF THE COLD FRONT MOVING INTO THE AREA SATURDAY NIGHT. WE HAVE
FOLLOWED THIS IDEA WITH LIKELY SHOWER AND THUNDERSTORM PROBABILITIES
AREA WIDE FOR SATURDAY NIGHT.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 320 PM EDT FRI MAY 31 2013
A COLD FRONT SHOULD BE ABOUT READY TO ENTER THE FORECAST AREA FROM
THE NW AT THE START OF THE PERIOD...WITH SUPPORT FROM AN APPROACHING
UPPER TROUGH...AND A RIBBON OF HIGHER DEW POINTS OFF THE GULF ALONG
THE FRONT BEING ADVECTED ALONG BY A 30-40 KT LOW LEVEL FLOW JUST OFF
THE SURFACE. ALL THIS CONSIDERED...THERE WILL LIKELY BE AN ONGOING
CONVECTIVE EVENT...WITH MODELS SHOWING THE GREATEST LIKELIHOOD OF
THIS IN THE SE PART OF THE AREA. AS THE FRONT SLOWLY PUSHES INTO AND
THROUGH THE FORECAST AREA SUNDAY AND SUNDAY EVENING...THERE COULD
ALSO BE ADDITIONAL DEVELOPMENT...WITH THE GREATEST OPPORTUNITY FOR
THIS IN THE SE WHERE FROPA WILL OCCUR LAST. THE LAST OF ANY
LINGERING PRECIP SHOULD END SUNDAY NIGHT OR EARLY MONDAY AS THE
FRONT CONTINUES ON TO OUR SE.
HIGH PRESSURE OVER THE MIDWEST WILL SUPPLY NOTICEABLY DRIER AND
SOMEWHAT COOLER AIR EARLY IN THE WEEK UNDER WNW FLOW ALOFT. RIDGING
ALOFT WILL PASS OVER ON TUESDAY INTO WEDNESDAY...WITH THE SURFACE
HIGH SHIFTING EASTWARD. THIS WILL BRING A CONTINUATION OF DRY
WEATHER...BUT WITH WARMING ALREADY OCCURRING AND AN EVENTUAL
INCREASE IN SURFACE MOISTURE.
AFTER THIS...MODEL DIFFERENCES BETWEEN THE GFS AND ECMWF BECOME MORE
APPARENT LATE IN THE WEEK. THE ECMWF DEVELOPS AN UPPER RIDGE OVER
THE CAROLINAS...BUT THIS FEATURE IS LACKING IN THE OPERATIONAL GFS.
ALL MODELS INDICATE AN UPPER LOW HEADING EAST ALONG THE CANADIAN
BORDER AND INTO ONTARIO...WITH A SOUTHWARD EXTENDING TROUGH. THE 00Z
ECMWF DOES NOT ALLOW AS MUCH OF A SOUTHERN EXTENSION OF THIS TROUGH
DUE TO ITS CAROLINA RIDGE. THE RESULT IS THAT THE GFS DEVELOPS
CONVECTION OVER THE LOCAL AREA FROM WEDNESDAY ON. MEANWHILE...THE
ECMWF SHOWS LIGHT PRECIP ONLY ON THURSDAY AS THE TROUGH SCOOTS BY TO
OUR NORTH. THE GEM AND GFS ENSEMBLE MEAN SUPPORT THE OPERATIONAL
GFS...AND PREFER TO WEIGHT THE FORECAST TOWARD IT...WITH JUST A BIT
OF ECMWF INFLUENCE TO KNOCK THE POPS DOWN SLIGHTLY FROM WHERE THEY
WOULD OTHERWISE BE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 121 PM EDT FRI MAY 31 2013
CONVECTION IS CURRENTLY DEVELOPING ACROSS CENTRAL KY AND EXPECT
SCATTERED SHOWERS AND THUNDERSTORMS TO MOVE INTO THE WESTERN PART OF
THE FORECAST AREA BY MID TO LATE AFTERNOON. CURRENT INDICATIONS ARE
THAT ANY CONVECTION THAT MOVES INTO OR DEVELOPS OVER EASTERN KY WILL
DECREASE QUICKLY EARLY THIS EVENING. THERE IS CONSIDERABLE
UNCERTAINTY HOW FAR EAST ANY SHOWERS OR THUNDERSTORMS WILL
OCCUR...AND AT THIS TIME WILL NOT MENTION ANY THUNDER IN THE JKL OR
LOZ TAF. WILL GO WITH VCTS IN THE SME TAF. OUTSIDE OF ANY SHOWER OR
THUNDERSTORMS VFR CONDITIONS WILL PREVAIL FOR THE REMAINDER OF THE
DAY. ALSO EXPECT VFR CONDITIONS TO PREVAIL TONIGHT AS WELL. THE
EXCEPTION TO THIS WOULD BE ANY AREAS THAT RECEIVE RAIN TODAY WHERE
OVERNIGHT FOG WOULD BE POSSIBLE. VFR WILL PREVAIL AGAIN SATURDAY
MORNING...WITH SHOWERS AND THUNDERSTORMS AGAIN POSSIBLE SATURDAY
AFTERNOON. AN APPROACHING COLD FRONT WILL BRING WIDESPREAD SHOWERS
AND THUNDERSTORMS SATURDAY NIGHT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...SBH
LONG TERM...HAL
AVIATION...SBH
AREA FORECAST DISCUSSION
NWS JACKSON KY
121 PM EDT FRI MAY 31 2013
.UPDATE...
ISSUED AT 1236 PM EDT FRI MAY 31 2013
MESOSCALE CONVECTIVE VORTEX EVIDENT IN RADAR IMAGERY NEAR MADISONVILLE
KY MOVING NE. AHEAD OF THIS A BROKEN LINE OF CONVECTION IS
INCREASING FROM LOUISVILLE SOUTHWARD TO THE EAST OF GLASGOW KY AND
THEN SOUTH INTO TN. THIS IS ALONG AN OUTFLOW FROM THIS MORNINGS
CONVECTION. CURRENT INDICATIONS ARE ADDITIONAL OUTFLOW FROM THIS
CONVECTION WILL TRIGGER SCATTERED SHOWERS AND THUNDERSTORMS
OVER THE SOUTHWEST PART OF THE FORECAST AREA BY 20Z IF NOT A LITTLE
SOONER. WILL CONTINUE WITH FORECAST OF SCATTERED SHOWERS AND
THUNDERSTORMS IN THE WESTERN PART OF FORECAST AREA THIS AFTERNOON AND
ISOLATED SHOWERS AND THUNDERSTORMS IN THE EAST. NDFD AND ZFP UPDATED.
UPDATE ISSUED AT 1024 AM EDT FRI MAY 31 2013
RADAR...SATELLITE AND LIGHTNING OBSERVATIONS ALL INDICATE A
WEAKENING TREND WITH CONVECTION OVER WESTERN KY. OUTFLOW FROM THIS
MAY TRIGGER CONVECTION OVER CENTRAL KY THIS AFTERNOON WITH A
MODERATELY UNSTABLE AIR MASS IN PLACE. THIS CONVECTION COULD THEN MAKE
ITS WAY INTO THE FORECAST AREA BY MID TO LATE AFTERNOON. THIS IDEA IS
SUPPORTED BY THE 12Z HRRR WHICH BRINGS SHOWERS AND THUNDERSTORMS INTO
THE WESTERN PART OF THE FORECAST AREA AROUND 20Z. PRIOR TO THIS
CONVECTION MAY BE INHIBITED DUE TO MID LEVEL CAPPING WHICH WAS
EVIDENT ON THE 12Z ILN SOUNDING. IN FACT THE SMALL SHOWERS THAT
DEVELOPED NORTHWEST OF FLEMING COUNTY AROUND 13Z EXHIBITED A WEAKENING
TREND ALMOST IMMEDIATELY AS THEY MOVED NNE INTO OH. THE HRRR DID A
GOOD JOB DEPICTING THE DEVELOPMENT OF SCATTERED SHOWERS IN THIS AREA
WITH A QUICK DISSIPATION TO THE SHOWERS. HAVE SLOWED THE ONSET OF
THUNDERSTORMS CHANCES FOR THIS AFTERNOON...AND LOWERED PROBABILITIES
ABOUT 10 PERCENT. WITH THIS IN MIND HAVE ALSO RAISED MAXIMUM
TEMPERATURES PRIMARILY IN THE EAST WHERE NEARLY THE ENTIRE DAY SHOULD
BE RAIN FREE. HOWEVER AFTERNOON TEMPERATURES WILL BE VERY DEPENDENT
ON SUNSHINE...AND THE CLOUD COVER FORECAST IS CHALLENGING AS DEBRIS
CLOUD FROM THIS MORNINGS CONVECTION MOVES EAST. UPDATED NDFD AND ZFP.
UPDATE ISSUED AT 735 AM EDT FRI MAY 31 2013
UPDATED THE FORECAST TO FINE TUNE THE POPS AND SKY THROUGH THE
MORNING HOURS....GENERALLY SLOWING THEM DOWN A TAD. ALSO APPLIED THE
LATEST OBS AND TRENDS TO THE T...TD...AND SKY GRIDS. IN ADDITION...
GIVEN THE ANTICIPATION OF ORGANIZED CONVECTIVE CLUSTERS AND UPPER
SUPPORT IN THE FORM OF THE TROUGH ANGLING THIS WAY ON SATURDAY WILL
ADD A BEEFIER MENTION OF THUNDERSTORMS...POSSIBLY SEVERE...TO THE
HWO. UPDATES HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. AN HWO
UPDATE WILL FOLLOW.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 350 AM EDT FRI MAY 31 2013
07Z SFC ANALYSIS SHOWS A LARGE AREA OF LOW PRESSURE...LOCATED OVER
THE NORTHERN PLAINS...STARTING TO AFFECT WESTERN KENTUCKY WHILE THE
WESTERN EXTENT OF HIGH PRESSURE OVER THE CAROLINAS IS HOLDING ON
OVER THE EAST. THIS HAS KEPT THE SKIES MOSTLY CLEAR THROUGH THE
NIGHT...THUS FAR...AND...WHEN COMBINED WITH LIGHT WINDS...ANOTHER
DECENT NIGHT OF RADIATIONAL COOLING IN UNDERWAY. AS IS NORMAL FOR
THESE SITUATIONS...THE SHELTERED VALLEYS HAVE DECOUPLED AND ARE
RUNNING A GOOD 10 DEGREES OR SO BELOW THE MILDER RIDGES WITH SPECIFIC
TEMPERATURES VARYING FROM AROUND 60 IN THE DEEPER SPOTS TO AROUND 70
ON THE HILLS...IN THE THERMAL BELT. DEWPOINTS ARE ABOUT THE SAME AS
LAST NIGHT WITH READINGS GENERALLY IN THE LOWER 60S. AGAIN...EXPECT
SOME PATCHY FOG IN THE DEEPER VALLEYS...BUT PRIMARILY JUST NEAR THE
RIVERS AND OTHER BODIES OF WATER.
THE MODELS ARE IN GOOD AGREEMENT ALOFT WITH THE SOUTHEAST RIDGING...
THAT HAS PROTECTED THE AREA FROM MOST OF THE CONVECTION THESE PAST
COUPLE OF DAYS...YIELDING TO THE DEVELOPING DEEP AND BROAD MID LEVEL
LOW OVER THE NORTHERN PLAINS. A COUPLE OF LEADING SHORTWAVES WILL
MOVE INTO THE OHIO VALLEY TODAY...BRUSHING BY TO THE NORTH OF OUR
CWA. FOLLOWING THIS...THE UPPER LOW WILL SLIP INTO THE UPPER MIDWEST
AND AS A RESULT DRIVE THE HEIGHTS DOWN THROUGHOUT KENTUCKY DURING
THE DAY SATURDAY. WITH THE MODELS SUCH AGREEMENT...HAVE BASICALLY
FOLLOWED A GENERAL BLEND AND KEYED IN ON THE HIGHER RESOLUTION NAM12
AND HRRR FOR DETAILS.
SENSIBLE WEATHER WILL FEATURE A CHANCE OF SHOWERS AND
THUNDERSTORMS...CURRENTLY AFFECTING WESTERN KENTUCKY...MOVING INTO
THE WESTERN PORTIONS OF EAST KENTUCKY LATER THIS MORNING AND THEN
DRIFTING EAST DURING THE REST OF THE DAY. THE EXTRA CLOUDS AND PCPN
AROUND SHOULD BE ENOUGH TO KEEP HIGH TEMPERATURES A BIT COOLER THAN
YESTERDAY. THE DAYTIME CONVECTION...FUELED BY SOME UPPER LEVEL
HELP...LOW LIS...MODERATE CAPE...AND ABOVE NORMAL PWS...WILL DIE OFF
BY EARLY EVENING LEAVING A MUGGY AIR MASS BEHIND FOR THE NIGHT WITH
ONLY A SMALL RIDGE TO VALLEY DIFFERENCE EXPECTED...BUT MORE IN THE
WAY OF PATCHY FOG. SATURDAY WILL SEE THE APPROACH OF THE SYSTEM/S
MAIN COLD FRONT AND THIS SHOULD BE ENOUGH TO KICK OFF ADDITIONAL AIR
MASS SHOWERS AND STORMS GIVEN A SIMILAR THERMAL AND MOISTURE PROFILE
AS FRIDAY.
AGAIN USED THE CONSSHORT FOR TD AND WINDS THROUGH THE FIRST 24 HOURS
AS A STARTING POINT...WITH HIGHS A BIT LOWER THAN THURSDAY FOR BOTH
TODAY AND SATURDAY...WHILE USING THE CONSALL FOR A STARTING POINT
TONIGHT. AS FOR POPS...GENERALLY ENDED UP CLOSER TO THE HIGHER MET
NUMBERS THROUGHOUT THE SHORT TERM PORTION OF THE FORECAST.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 300 AM EDT FRI MAY 31 2013
A MID/UPPER LEVEL TROUGH WILL SWING ACROSS KENTUCKY SATURDAY NIGHT
INTO SUNDAY NIGHT...PRODUCING A PERIOD OF SHOWERS AND THUNDERSTORMS
FOR THE AREA. MODELS ARE ALL IN PRETTY DECENT AGREEMENT SO HAVE
INCREASED POPS FROM LATE SATURDAY NIGHT INTO SUNDAY. SEVERE THREAT
IS FAIRLY MINIMAL AS CLOUD COVER MAY LIMIT INSTABILITY AND SHEAR IS
QUITE WEAK. FRONT WILL DEPART TO THE SOUTH SUNDAY NIGHT...WITH RAIN
CHANCES DROPPING SOUTHEASTWARD. A COOLER AND LESS HUMID AIRMASS WILL
SETTLE INTO THE AREA FOR THE EARLY PORTION OF NEXT WEEK...ALLOWING
FOR VERY PLEASANT CONDITIONS FOR EARLY JUNE. ANOTHER RIDGE OF HIGH
PRESSURE WILL BUILD OVER THE SOUTHEAST BY THE MIDDLE TO LATE
PORTIONS OF NEXT WEEK WITH RETURN FLOW AGAIN ESTABLISHING ITSELF
OVER THE AREA. AS MOISTURE INCREASES BY MIDWEEK...RAIN CHANCES WILL
SLOWLY RAMP UP SIMILAR TO THIS PAST WEEK. TEMPERATURES WILL TURN
MILDER AS WELL AS THE WEEK GOES ON. MODELS ARE ALL IN DECENT
AGREEMENT THROUGH THE END OF NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 121 PM EDT FRI MAY 31 2013
CONVECTION IS CURRENTLY DEVELOPING ACROSS CENTRAL KY AND EXPECT
SCATTERED SHOWERS AND THUNDERSTORMS TO MOVE INTO THE WESTERN PART OF
THE FORECAST AREA BY MID TO LATE AFTERNOON. CURRENT INDICATIONS ARE
THAT ANY CONVECTION THAT MOVES INTO OR DEVELOPS OVER EASTERN KY WILL
DECREASE QUICKLY EARLY THIS EVENING. THERE IS CONSIDERABLE
UNCERTAINTY HOW FAR EAST ANY SHOWERS OR THUNDERSTORMS WILL
OCCUR...AND AT THIS TIME WILL NOT MENTION ANY THUNDER IN THE JKL OR
LOZ TAF. WILL GO WITH VCTS IN THE SME TAF. OUTSIDE OF ANY SHOWER OR
THUNDERSTORMS VFR CONDITIONS WILL PREVAIL FOR THE REMAINDER OF THE
DAY. ALSO EXPECT VFR CONDITIONS TO PREVAIL TONIGHT AS WELL. THE
EXCEPTION TO THIS WOULD BE ANY AREAS THAT RECEIVE RAIN TODAY WHERE
OVERNIGHT FOG WOULD BE POSSIBLE. VFR WILL PREVAIL AGAIN SATURDAY
MORNING...WITH SHOWERS AND THUNDERSTORMS AGAIN POSSIBLE SATURDAY
AFTERNOON. AN APPROACHING COLD FRONT WILL BRING WIDESPREAD SHOWERS
AND THUNDERSTORMS SATURDAY NIGHT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...GREIF
LONG TERM...KAS
AVIATION...SBH
AREA FORECAST DISCUSSION
NWS JACKSON KY
1237 PM EDT FRI MAY 31 2013
.UPDATE...
ISSUED AT 1236 PM EDT FRI MAY 31 2013
MESOSCALE CONVECTIVE VORTEX EVIDENT IN RADAR IMAGERY NEAR MADISONVILLE
KY MOVING NE. AHEAD OF THIS A BROKEN LINE OF CONVECTION IS
INCREASING FROM LOUISVILLE SOUTHWARD TO THE EAST OF GLASGOW KY AND
THEN SOUTH INTO TN. THIS IS ALONG AN OUTFLOW FROM THIS MORNINGS
CONVECTION. CURRENT INDICATIONS ARE ADDITIONAL OUTFLOW FROM THIS
CONVECTION WILL TRIGGER SCATTERED SHOWERS AND THUNDERSTORMS
OVER THE SOUTHWEST PART OF THE FORECAST AREA BY 20Z IF NOT A LITTLE
SOONER. WILL CONTINUE WITH FORECAST OF SCATTERED SHOWERS AND
THUNDERSTORMS IN THE WESTERN PART OF FORECAST AREA THIS AFTERNOON AND
ISOLATED SHOWERS AND THUNDERSTORMS IN THE EAST. NDFD AND ZFP UPDATED.
UPDATE ISSUED AT 1024 AM EDT FRI MAY 31 2013
RADAR...SATELLITE AND LIGHTNING OBSERVATIONS ALL INDICATE A
WEAKENING TREND WITH CONVECTION OVER WESTERN KY. OUTFLOW FROM THIS
MAY TRIGGER CONVECTION OVER CENTRAL KY THIS AFTERNOON WITH A
MODERATELY UNSTABLE AIR MASS IN PLACE. THIS CONVECTION COULD THEN MAKE
ITS WAY INTO THE FORECAST AREA BY MID TO LATE AFTERNOON. THIS IDEA IS
SUPPORTED BY THE 12Z HRRR WHICH BRINGS SHOWERS AND THUNDERSTORMS INTO
THE WESTERN PART OF THE FORECAST AREA AROUND 20Z. PRIOR TO THIS
CONVECTION MAY BE INHIBITED DUE TO MID LEVEL CAPPING WHICH WAS
EVIDENT ON THE 12Z ILN SOUNDING. IN FACT THE SMALL SHOWERS THAT
DEVELOPED NORTHWEST OF FLEMING COUNTY AROUND 13Z EXHIBITED A WEAKENING
TREND ALMOST IMMEDIATELY AS THEY MOVED NNE INTO OH. THE HRRR DID A
GOOD JOB DEPICTING THE DEVELOPMENT OF SCATTERED SHOWERS IN THIS AREA
WITH A QUICK DISSIPATION TO THE SHOWERS. HAVE SLOWED THE ONSET OF
THUNDERSTORMS CHANCES FOR THIS AFTERNOON...AND LOWERED PROBABILITIES
ABOUT 10 PERCENT. WITH THIS IN MIND HAVE ALSO RAISED MAXIMUM
TEMPERATURES PRIMARILY IN THE EAST WHERE NEARLY THE ENTIRE DAY SHOULD
BE RAIN FREE. HOWEVER AFTERNOON TEMPERATURES WILL BE VERY DEPENDENT
ON SUNSHINE...AND THE CLOUD COVER FORECAST IS CHALLENGING AS DEBRIS
CLOUD FROM THIS MORNINGS CONVECTION MOVES EAST. UPDATED NDFD AND ZFP.
UPDATE ISSUED AT 735 AM EDT FRI MAY 31 2013
UPDATED THE FORECAST TO FINE TUNE THE POPS AND SKY THROUGH THE
MORNING HOURS....GENERALLY SLOWING THEM DOWN A TAD. ALSO APPLIED THE
LATEST OBS AND TRENDS TO THE T...TD...AND SKY GRIDS. IN ADDITION...
GIVEN THE ANTICIPATION OF ORGANIZED CONVECTIVE CLUSTERS AND UPPER
SUPPORT IN THE FORM OF THE TROUGH ANGLING THIS WAY ON SATURDAY WILL
ADD A BEEFIER MENTION OF THUNDERSTORMS...POSSIBLY SEVERE...TO THE
HWO. UPDATES HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. AN HWO
UPDATE WILL FOLLOW.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 350 AM EDT FRI MAY 31 2013
07Z SFC ANALYSIS SHOWS A LARGE AREA OF LOW PRESSURE...LOCATED OVER
THE NORTHERN PLAINS...STARTING TO AFFECT WESTERN KENTUCKY WHILE THE
WESTERN EXTENT OF HIGH PRESSURE OVER THE CAROLINAS IS HOLDING ON
OVER THE EAST. THIS HAS KEPT THE SKIES MOSTLY CLEAR THROUGH THE
NIGHT...THUS FAR...AND...WHEN COMBINED WITH LIGHT WINDS...ANOTHER
DECENT NIGHT OF RADIATIONAL COOLING IN UNDERWAY. AS IS NORMAL FOR
THESE SITUATIONS...THE SHELTERED VALLEYS HAVE DECOUPLED AND ARE
RUNNING A GOOD 10 DEGREES OR SO BELOW THE MILDER RIDGES WITH SPECIFIC
TEMPERATURES VARYING FROM AROUND 60 IN THE DEEPER SPOTS TO AROUND 70
ON THE HILLS...IN THE THERMAL BELT. DEWPOINTS ARE ABOUT THE SAME AS
LAST NIGHT WITH READINGS GENERALLY IN THE LOWER 60S. AGAIN...EXPECT
SOME PATCHY FOG IN THE DEEPER VALLEYS...BUT PRIMARILY JUST NEAR THE
RIVERS AND OTHER BODIES OF WATER.
THE MODELS ARE IN GOOD AGREEMENT ALOFT WITH THE SOUTHEAST RIDGING...
THAT HAS PROTECTED THE AREA FROM MOST OF THE CONVECTION THESE PAST
COUPLE OF DAYS...YIELDING TO THE DEVELOPING DEEP AND BROAD MID LEVEL
LOW OVER THE NORTHERN PLAINS. A COUPLE OF LEADING SHORTWAVES WILL
MOVE INTO THE OHIO VALLEY TODAY...BRUSHING BY TO THE NORTH OF OUR
CWA. FOLLOWING THIS...THE UPPER LOW WILL SLIP INTO THE UPPER MIDWEST
AND AS A RESULT DRIVE THE HEIGHTS DOWN THROUGHOUT KENTUCKY DURING
THE DAY SATURDAY. WITH THE MODELS SUCH AGREEMENT...HAVE BASICALLY
FOLLOWED A GENERAL BLEND AND KEYED IN ON THE HIGHER RESOLUTION NAM12
AND HRRR FOR DETAILS.
SENSIBLE WEATHER WILL FEATURE A CHANCE OF SHOWERS AND
THUNDERSTORMS...CURRENTLY AFFECTING WESTERN KENTUCKY...MOVING INTO
THE WESTERN PORTIONS OF EAST KENTUCKY LATER THIS MORNING AND THEN
DRIFTING EAST DURING THE REST OF THE DAY. THE EXTRA CLOUDS AND PCPN
AROUND SHOULD BE ENOUGH TO KEEP HIGH TEMPERATURES A BIT COOLER THAN
YESTERDAY. THE DAYTIME CONVECTION...FUELED BY SOME UPPER LEVEL
HELP...LOW LIS...MODERATE CAPE...AND ABOVE NORMAL PWS...WILL DIE OFF
BY EARLY EVENING LEAVING A MUGGY AIR MASS BEHIND FOR THE NIGHT WITH
ONLY A SMALL RIDGE TO VALLEY DIFFERENCE EXPECTED...BUT MORE IN THE
WAY OF PATCHY FOG. SATURDAY WILL SEE THE APPROACH OF THE SYSTEM/S
MAIN COLD FRONT AND THIS SHOULD BE ENOUGH TO KICK OFF ADDITIONAL AIR
MASS SHOWERS AND STORMS GIVEN A SIMILAR THERMAL AND MOISTURE PROFILE
AS FRIDAY.
AGAIN USED THE CONSSHORT FOR TD AND WINDS THROUGH THE FIRST 24 HOURS
AS A STARTING POINT...WITH HIGHS A BIT LOWER THAN THURSDAY FOR BOTH
TODAY AND SATURDAY...WHILE USING THE CONSALL FOR A STARTING POINT
TONIGHT. AS FOR POPS...GENERALLY ENDED UP CLOSER TO THE HIGHER MET
NUMBERS THROUGHOUT THE SHORT TERM PORTION OF THE FORECAST.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 300 AM EDT FRI MAY 31 2013
A MID/UPPER LEVEL TROUGH WILL SWING ACROSS KENTUCKY SATURDAY NIGHT
INTO SUNDAY NIGHT...PRODUCING A PERIOD OF SHOWERS AND THUNDERSTORMS
FOR THE AREA. MODELS ARE ALL IN PRETTY DECENT AGREEMENT SO HAVE
INCREASED POPS FROM LATE SATURDAY NIGHT INTO SUNDAY. SEVERE THREAT
IS FAIRLY MINIMAL AS CLOUD COVER MAY LIMIT INSTABILITY AND SHEAR IS
QUITE WEAK. FRONT WILL DEPART TO THE SOUTH SUNDAY NIGHT...WITH RAIN
CHANCES DROPPING SOUTHEASTWARD. A COOLER AND LESS HUMID AIRMASS WILL
SETTLE INTO THE AREA FOR THE EARLY PORTION OF NEXT WEEK...ALLOWING
FOR VERY PLEASANT CONDITIONS FOR EARLY JUNE. ANOTHER RIDGE OF HIGH
PRESSURE WILL BUILD OVER THE SOUTHEAST BY THE MIDDLE TO LATE
PORTIONS OF NEXT WEEK WITH RETURN FLOW AGAIN ESTABLISHING ITSELF
OVER THE AREA. AS MOISTURE INCREASES BY MIDWEEK...RAIN CHANCES WILL
SLOWLY RAMP UP SIMILAR TO THIS PAST WEEK. TEMPERATURES WILL TURN
MILDER AS WELL AS THE WEEK GOES ON. MODELS ARE ALL IN DECENT
AGREEMENT THROUGH THE END OF NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 745 AM EDT FRI MAY 31 2013
A COUPLE MID LEVEL SHORTWAVES WILL PASS JUST NORTH OF THE AREA TODAY.
THE FIRST OF THESE IS RESPONSIBLE FOR THE AREA OF CONVECTION OVER
WESTERN KENTUCKY. THIS AREA IS EXPECTED TO PUSH EAST INTO THE AREA
LATE THIS MORNING...BUT QUESTIONS REMAIN WHETHER IT WILL BE DECAYING
OR STEADY STATE WHEN IT ENTERS...AIDED BY THE BUILDING INSTABILITY
WROUGHT BY DIURNAL HEATING. SINCE THE EXACT TIMING AND LOCATION OF
THIS REMNANT OR HEALTHY CONVECTIVE CLUSTER COME MIDDAY IS STILL
UNCERTAIN HAVE GONE WITH VCTS. THIS FIRST SURGE OF CONVECTION WILL
DIE OUT BY EVENING AND FOLLOWING THAT EXPECT THE CIGS TO SCATTER OUT.
THE INPUT OF MORE MOISTURE IN THE ENVIRONMENT WILL INCREASE THE
POTENTIAL FOR PATCHY VALLEY FOG LATE TONIGHT. WINDS THROUGHOUT THE
PERIOD WILL BE AROUND 10 KTS...OR LESS...AND GENERALLY FROM THE
SOUTH.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...GREIF
LONG TERM...KAS
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS JACKSON KY
1025 AM EDT FRI MAY 31 2013
.UPDATE...
ISSUED AT 1024 AM EDT FRI MAY 31 2013
RADAR...SATELLITE AND LIGHTNING OBSERVATIONS ALL INDICATE A
WEAKENING TREND WITH CONVECTION OVER WESTERN KY. OUTFLOW FROM THIS
MAY TRIGGER CONVECTION OVER CENTRAL KY THIS AFTERNOON WITH A
MODERATELY UNSTABLE AIR MASS IN PLACE. THIS CONVECTION COULD THEN MAKE
ITS WAY INTO THE FORECAST AREA BY MID TO LATE AFTERNOON. THIS IDEA IS
SUPPORTED BY THE 12Z HRRR WHICH BRINGS SHOWERS AND THUNDERSTORMS INTO
THE WESTERN PART OF THE FORECAST AREA AROUND 20Z. PRIOR TO THIS
CONVECTION MAY BE INHIBITED DUE TO MID LEVEL CAPPING WHICH WAS
EVIDENT ON THE 12Z ILN SOUNDING. IN FACT THE SMALL SHOWERS THAT
DEVELOPED NORTHWEST OF FLEMING COUNTY AROUND 13Z EXHIBITED A WEAKENING
TREND ALMOST IMMEDIATELY AS THEY MOVED NNE INTO OH. THE HRRR DID A
GOOD JOB DEPICTING THE DEVELOPMENT OF SCATTERED SHOWERS IN THIS AREA
WITH A QUICK DISSIPATION TO THE SHOWERS. HAVE SLOWED THE ONSET OF
THUNDERSTORMS CHANCES FOR THIS AFTERNOON...AND LOWERED PROBABILITIES
ABOUT 10 PERCENT. WITH THIS IN MIND HAVE ALSO RAISED MAXIMUM
TEMPERATURES PRIMARILY IN THE EAST WHERE NEARLY THE ENTIRE DAY SHOULD
BE RAIN FREE. HOWEVER AFTERNOON TEMPERATURES WILL BE VERY DEPENDENT
ON SUNSHINE...AND THE CLOUD COVER FORECAST IS CHALLENGING AS DEBRIS
CLOUD FROM THIS MORNINGS CONVECTION MOVES EAST. UPDATED NDFD AND ZFP.
UPDATE ISSUED AT 735 AM EDT FRI MAY 31 2013
UPDATED THE FORECAST TO FINE TUNE THE POPS AND SKY THROUGH THE
MORNING HOURS....GENERALLY SLOWING THEM DOWN A TAD. ALSO APPLIED THE
LATEST OBS AND TRENDS TO THE T...TD...AND SKY GRIDS. IN ADDITION...
GIVEN THE ANTICIPATION OF ORGANIZED CONVECTIVE CLUSTERS AND UPPER
SUPPORT IN THE FORM OF THE TROUGH ANGLING THIS WAY ON SATURDAY WILL
ADD A BEEFIER MENTION OF THUNDERSTORMS...POSSIBLY SEVERE...TO THE
HWO. UPDATES HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. AN HWO
UPDATE WILL FOLLOW.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 350 AM EDT FRI MAY 31 2013
07Z SFC ANALYSIS SHOWS A LARGE AREA OF LOW PRESSURE...LOCATED OVER
THE NORTHERN PLAINS...STARTING TO AFFECT WESTERN KENTUCKY WHILE THE
WESTERN EXTENT OF HIGH PRESSURE OVER THE CAROLINAS IS HOLDING ON
OVER THE EAST. THIS HAS KEPT THE SKIES MOSTLY CLEAR THROUGH THE
NIGHT...THUS FAR...AND...WHEN COMBINED WITH LIGHT WINDS...ANOTHER
DECENT NIGHT OF RADIATIONAL COOLING IN UNDERWAY. AS IS NORMAL FOR
THESE SITUATIONS...THE SHELTERED VALLEYS HAVE DECOUPLED AND ARE
RUNNING A GOOD 10 DEGREES OR SO BELOW THE MILDER RIDGES WITH SPECIFIC
TEMPERATURES VARYING FROM AROUND 60 IN THE DEEPER SPOTS TO AROUND 70
ON THE HILLS...IN THE THERMAL BELT. DEWPOINTS ARE ABOUT THE SAME AS
LAST NIGHT WITH READINGS GENERALLY IN THE LOWER 60S. AGAIN...EXPECT
SOME PATCHY FOG IN THE DEEPER VALLEYS...BUT PRIMARILY JUST NEAR THE
RIVERS AND OTHER BODIES OF WATER.
THE MODELS ARE IN GOOD AGREEMENT ALOFT WITH THE SOUTHEAST RIDGING...
THAT HAS PROTECTED THE AREA FROM MOST OF THE CONVECTION THESE PAST
COUPLE OF DAYS...YIELDING TO THE DEVELOPING DEEP AND BROAD MID LEVEL
LOW OVER THE NORTHERN PLAINS. A COUPLE OF LEADING SHORTWAVES WILL
MOVE INTO THE OHIO VALLEY TODAY...BRUSHING BY TO THE NORTH OF OUR
CWA. FOLLOWING THIS...THE UPPER LOW WILL SLIP INTO THE UPPER MIDWEST
AND AS A RESULT DRIVE THE HEIGHTS DOWN THROUGHOUT KENTUCKY DURING
THE DAY SATURDAY. WITH THE MODELS SUCH AGREEMENT...HAVE BASICALLY
FOLLOWED A GENERAL BLEND AND KEYED IN ON THE HIGHER RESOLUTION NAM12
AND HRRR FOR DETAILS.
SENSIBLE WEATHER WILL FEATURE A CHANCE OF SHOWERS AND
THUNDERSTORMS...CURRENTLY AFFECTING WESTERN KENTUCKY...MOVING INTO
THE WESTERN PORTIONS OF EAST KENTUCKY LATER THIS MORNING AND THEN
DRIFTING EAST DURING THE REST OF THE DAY. THE EXTRA CLOUDS AND PCPN
AROUND SHOULD BE ENOUGH TO KEEP HIGH TEMPERATURES A BIT COOLER THAN
YESTERDAY. THE DAYTIME CONVECTION...FUELED BY SOME UPPER LEVEL
HELP...LOW LIS...MODERATE CAPE...AND ABOVE NORMAL PWS...WILL DIE OFF
BY EARLY EVENING LEAVING A MUGGY AIR MASS BEHIND FOR THE NIGHT WITH
ONLY A SMALL RIDGE TO VALLEY DIFFERENCE EXPECTED...BUT MORE IN THE
WAY OF PATCHY FOG. SATURDAY WILL SEE THE APPROACH OF THE SYSTEM/S
MAIN COLD FRONT AND THIS SHOULD BE ENOUGH TO KICK OFF ADDITIONAL AIR
MASS SHOWERS AND STORMS GIVEN A SIMILAR THERMAL AND MOISTURE PROFILE
AS FRIDAY.
AGAIN USED THE CONSSHORT FOR TD AND WINDS THROUGH THE FIRST 24 HOURS
AS A STARTING POINT...WITH HIGHS A BIT LOWER THAN THURSDAY FOR BOTH
TODAY AND SATURDAY...WHILE USING THE CONSALL FOR A STARTING POINT
TONIGHT. AS FOR POPS...GENERALLY ENDED UP CLOSER TO THE HIGHER MET
NUMBERS THROUGHOUT THE SHORT TERM PORTION OF THE FORECAST.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 300 AM EDT FRI MAY 31 2013
A MID/UPPER LEVEL TROUGH WILL SWING ACROSS KENTUCKY SATURDAY NIGHT
INTO SUNDAY NIGHT...PRODUCING A PERIOD OF SHOWERS AND THUNDERSTORMS
FOR THE AREA. MODELS ARE ALL IN PRETTY DECENT AGREEMENT SO HAVE
INCREASED POPS FROM LATE SATURDAY NIGHT INTO SUNDAY. SEVERE THREAT
IS FAIRLY MINIMAL AS CLOUD COVER MAY LIMIT INSTABILITY AND SHEAR IS
QUITE WEAK. FRONT WILL DEPART TO THE SOUTH SUNDAY NIGHT...WITH RAIN
CHANCES DROPPING SOUTHEASTWARD. A COOLER AND LESS HUMID AIRMASS WILL
SETTLE INTO THE AREA FOR THE EARLY PORTION OF NEXT WEEK...ALLOWING
FOR VERY PLEASANT CONDITIONS FOR EARLY JUNE. ANOTHER RIDGE OF HIGH
PRESSURE WILL BUILD OVER THE SOUTHEAST BY THE MIDDLE TO LATE
PORTIONS OF NEXT WEEK WITH RETURN FLOW AGAIN ESTABLISHING ITSELF
OVER THE AREA. AS MOISTURE INCREASES BY MIDWEEK...RAIN CHANCES WILL
SLOWLY RAMP UP SIMILAR TO THIS PAST WEEK. TEMPERATURES WILL TURN
MILDER AS WELL AS THE WEEK GOES ON. MODELS ARE ALL IN DECENT
AGREEMENT THROUGH THE END OF NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 745 AM EDT FRI MAY 31 2013
A COUPLE MID LEVEL SHORTWAVES WILL PASS JUST NORTH OF THE AREA TODAY.
THE FIRST OF THESE IS RESPONSIBLE FOR THE AREA OF CONVECTION OVER
WESTERN KENTUCKY. THIS AREA IS EXPECTED TO PUSH EAST INTO THE AREA
LATE THIS MORNING...BUT QUESTIONS REMAIN WHETHER IT WILL BE DECAYING
OR STEADY STATE WHEN IT ENTERS...AIDED BY THE BUILDING INSTABILITY
WROUGHT BY DIURNAL HEATING. SINCE THE EXACT TIMING AND LOCATION OF
THIS REMNANT OR HEALTHY CONVECTIVE CLUSTER COME MIDDAY IS STILL
UNCERTAIN HAVE GONE WITH VCTS. THIS FIRST SURGE OF CONVECTION WILL
DIE OUT BY EVENING AND FOLLOWING THAT EXPECT THE CIGS TO SCATTER OUT.
THE INPUT OF MORE MOISTURE IN THE ENVIRONMENT WILL INCREASE THE
POTENTIAL FOR PATCHY VALLEY FOG LATE TONIGHT. WINDS THROUGHOUT THE
PERIOD WILL BE AROUND 10 KTS...OR LESS...AND GENERALLY FROM THE
SOUTH.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...GREIF
LONG TERM...KAS
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
745 AM EDT FRI MAY 31 2013
.UPDATE...
ISSUED AT 735 AM EDT FRI MAY 31 2013
UPDATED THE FORECAST TO FINE TUNE THE POPS AND SKY THROUGH THE
MORNING HOURS....GENERALLY SLOWING THEM DOWN A TAD. ALSO APPLIED THE
LATEST OBS AND TRENDS TO THE T...TD...AND SKY GRIDS. IN ADDITION...
GIVEN THE ANTICIPATION OF ORGANIZED CONVECTIVE CLUSTERS AND UPPER
SUPPORT IN THE FORM OF THE TROUGH ANGLING THIS WAY ON SATURDAY WILL
ADD A BEEFIER MENTION OF THUNDERSTORMS...POSSIBLY SEVERE...TO THE
HWO. UPDATES HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. AN HWO
UPDATE WILL FOLLOW.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 350 AM EDT FRI MAY 31 2013
07Z SFC ANALYSIS SHOWS A LARGE AREA OF LOW PRESSURE...LOCATED OVER
THE NORTHERN PLAINS...STARTING TO AFFECT WESTERN KENTUCKY WHILE THE
WESTERN EXTENT OF HIGH PRESSURE OVER THE CAROLINAS IS HOLDING ON
OVER THE EAST. THIS HAS KEPT THE SKIES MOSTLY CLEAR THROUGH THE
NIGHT...THUS FAR...AND...WHEN COMBINED WITH LIGHT WINDS...ANOTHER
DECENT NIGHT OF RADIATIONAL COOLING IN UNDERWAY. AS IS NORMAL FOR
THESE SITUATIONS...THE SHELTERED VALLEYS HAVE DECOUPLED AND ARE
RUNNING A GOOD 10 DEGREES OR SO BELOW THE MILDER RIDGES WITH SPECIFIC
TEMPERATURES VARYING FROM AROUND 60 IN THE DEEPER SPOTS TO AROUND 70
ON THE HILLS...IN THE THERMAL BELT. DEWPOINTS ARE ABOUT THE SAME AS
LAST NIGHT WITH READINGS GENERALLY IN THE LOWER 60S. AGAIN...EXPECT
SOME PATCHY FOG IN THE DEEPER VALLEYS...BUT PRIMARILY JUST NEAR THE
RIVERS AND OTHER BODIES OF WATER.
THE MODELS ARE IN GOOD AGREEMENT ALOFT WITH THE SOUTHEAST RIDGING...
THAT HAS PROTECTED THE AREA FROM MOST OF THE CONVECTION THESE PAST
COUPLE OF DAYS...YIELDING TO THE DEVELOPING DEEP AND BROAD MID LEVEL
LOW OVER THE NORTHERN PLAINS. A COUPLE OF LEADING SHORTWAVES WILL
MOVE INTO THE OHIO VALLEY TODAY...BRUSHING BY TO THE NORTH OF OUR
CWA. FOLLOWING THIS...THE UPPER LOW WILL SLIP INTO THE UPPER MIDWEST
AND AS A RESULT DRIVE THE HEIGHTS DOWN THROUGHOUT KENTUCKY DURING
THE DAY SATURDAY. WITH THE MODELS SUCH AGREEMENT...HAVE BASICALLY
FOLLOWED A GENERAL BLEND AND KEYED IN ON THE HIGHER RESOLUTION NAM12
AND HRRR FOR DETAILS.
SENSIBLE WEATHER WILL FEATURE A CHANCE OF SHOWERS AND
THUNDERSTORMS...CURRENTLY AFFECTING WESTERN KENTUCKY...MOVING INTO
THE WESTERN PORTIONS OF EAST KENTUCKY LATER THIS MORNING AND THEN
DRIFTING EAST DURING THE REST OF THE DAY. THE EXTRA CLOUDS AND PCPN
AROUND SHOULD BE ENOUGH TO KEEP HIGH TEMPERATURES A BIT COOLER THAN
YESTERDAY. THE DAYTIME CONVECTION...FUELED BY SOME UPPER LEVEL
HELP...LOW LIS...MODERATE CAPE...AND ABOVE NORMAL PWS...WILL DIE OFF
BY EARLY EVENING LEAVING A MUGGY AIR MASS BEHIND FOR THE NIGHT WITH
ONLY A SMALL RIDGE TO VALLEY DIFFERENCE EXPECTED...BUT MORE IN THE
WAY OF PATCHY FOG. SATURDAY WILL SEE THE APPROACH OF THE SYSTEM/S
MAIN COLD FRONT AND THIS SHOULD BE ENOUGH TO KICK OFF ADDITIONAL AIR
MASS SHOWERS AND STORMS GIVEN A SIMILAR THERMAL AND MOISTURE PROFILE
AS FRIDAY.
AGAIN USED THE CONSSHORT FOR TD AND WINDS THROUGH THE FIRST 24 HOURS
AS A STARTING POINT...WITH HIGHS A BIT LOWER THAN THURSDAY FOR BOTH
TODAY AND SATURDAY...WHILE USING THE CONSALL FOR A STARTING POINT
TONIGHT. AS FOR POPS...GENERALLY ENDED UP CLOSER TO THE HIGHER MET
NUMBERS THROUGHOUT THE SHORT TERM PORTION OF THE FORECAST.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 300 AM EDT FRI MAY 31 2013
A MID/UPPER LEVEL TROUGH WILL SWING ACROSS KENTUCKY SATURDAY NIGHT
INTO SUNDAY NIGHT...PRODUCING A PERIOD OF SHOWERS AND THUNDERSTORMS
FOR THE AREA. MODELS ARE ALL IN PRETTY DECENT AGREEMENT SO HAVE
INCREASED POPS FROM LATE SATURDAY NIGHT INTO SUNDAY. SEVERE THREAT
IS FAIRLY MINIMAL AS CLOUD COVER MAY LIMIT INSTABILITY AND SHEAR IS
QUITE WEAK. FRONT WILL DEPART TO THE SOUTH SUNDAY NIGHT...WITH RAIN
CHANCES DROPPING SOUTHEASTWARD. A COOLER AND LESS HUMID AIRMASS WILL
SETTLE INTO THE AREA FOR THE EARLY PORTION OF NEXT WEEK...ALLOWING
FOR VERY PLEASANT CONDITIONS FOR EARLY JUNE. ANOTHER RIDGE OF HIGH
PRESSURE WILL BUILD OVER THE SOUTHEAST BY THE MIDDLE TO LATE
PORTIONS OF NEXT WEEK WITH RETURN FLOW AGAIN ESTABLISHING ITSELF
OVER THE AREA. AS MOISTURE INCREASES BY MIDWEEK...RAIN CHANCES WILL
SLOWLY RAMP UP SIMILAR TO THIS PAST WEEK. TEMPERATURES WILL TURN
MILDER AS WELL AS THE WEEK GOES ON. MODELS ARE ALL IN DECENT
AGREEMENT THROUGH THE END OF NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 745 AM EDT FRI MAY 31 2013
A COUPLE MID LEVEL SHORTWAVES WILL PASS JUST NORTH OF THE AREA TODAY.
THE FIRST OF THESE IS RESPONSIBLE FOR THE AREA OF CONVECTION OVER
WESTERN KENTUCKY. THIS AREA IS EXPECTED TO PUSH EAST INTO THE AREA
LATE THIS MORNING...BUT QUESTIONS REMAIN WHETHER IT WILL BE DECAYING
OR STEADY STATE WHEN IT ENTERS...AIDED BY THE BUILDING INSTABILITY
WROUGHT BY DIURNAL HEATING. SINCE THE EXACT TIMING AND LOCATION OF
THIS REMNANT OR HEALTHY CONVECTIVE CLUSTER COME MIDDAY IS STILL
UNCERTAIN HAVE GONE WITH VCTS. THIS FIRST SURGE OF CONVECTION WILL
DIE OUT BY EVENING AND FOLLOWING THAT EXPECT THE CIGS TO SCATTER OUT.
THE INPUT OF MORE MOISTURE IN THE ENVIRONMENT WILL INCREASE THE
POTENTIAL FOR PATCHY VALLEY FOG LATE TONIGHT. WINDS THROUGHOUT THE
PERIOD WILL BE AROUND 10 KTS...OR LESS...AND GENERALLY FROM THE
SOUTH.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...GREIF
LONG TERM...KAS
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
350 AM EDT FRI MAY 31 2013
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 350 AM EDT FRI MAY 31 2013
07Z SFC ANALYSIS SHOWS A LARGE AREA OF LOW PRESSURE...LOCATED OVER
THE NORTHERN PLAINS...STARTING TO AFFECT WESTERN KENTUCKY WHILE THE
WESTERN EXTENT OF HIGH PRESSURE OVER THE CAROLINAS IS HOLDING ON
OVER THE EAST. THIS HAS KEPT THE SKIES MOSTLY CLEAR THROUGH THE
NIGHT...THUS FAR...AND...WHEN COMBINED WITH LIGHT WINDS...ANOTHER
DECENT NIGHT OF RADIATIONAL COOLING IN UNDERWAY. AS IS NORMAL FOR
THESE SITUATIONS...THE SHELTERED VALLEYS HAVE DECOUPLED AND ARE
RUNNING A GOOD 10 DEGREES OR SO BELOW THE MILDER RIDGES WITH SPECIFIC
TEMPERATURES VARYING FROM AROUND 60 IN THE DEEPER SPOTS TO AROUND 70
ON THE HILLS...IN THE THERMAL BELT. DEWPOINTS ARE ABOUT THE SAME AS
LAST NIGHT WITH READINGS GENERALLY IN THE LOWER 60S. AGAIN...EXPECT
SOME PATCHY FOG IN THE DEEPER VALLEYS...BUT PRIMARILY JUST NEAR THE
RIVERS AND OTHER BODIES OF WATER.
THE MODELS ARE IN GOOD AGREEMENT ALOFT WITH THE SOUTHEAST RIDGING...
THAT HAS PROTECTED THE AREA FROM MOST OF THE CONVECTION THESE PAST
COUPLE OF DAYS...YIELDING TO THE DEVELOPING DEEP AND BROAD MID LEVEL
LOW OVER THE NORTHERN PLAINS. A COUPLE OF LEADING SHORTWAVES WILL
MOVE INTO THE OHIO VALLEY TODAY...BRUSHING BY TO THE NORTH OF OUR
CWA. FOLLOWING THIS...THE UPPER LOW WILL SLIP INTO THE UPPER MIDWEST
AND AS A RESULT DRIVE THE HEIGHTS DOWN THROUGHOUT KENTUCKY DURING
THE DAY SATURDAY. WITH THE MODELS SUCH AGREEMENT...HAVE BASICALLY
FOLLOWED A GENERAL BLEND AND KEYED IN ON THE HIGHER RESOLUTION NAM12
AND HRRR FOR DETAILS.
SENSIBLE WEATHER WILL FEATURE A CHANCE OF SHOWERS AND
THUNDERSTORMS...CURRENTLY AFFECTING WESTERN KENTUCKY...MOVING INTO
THE WESTERN PORTIONS OF EAST KENTUCKY LATER THIS MORNING AND THEN
DRIFTING EAST DURING THE REST OF THE DAY. THE EXTRA CLOUDS AND PCPN
AROUND SHOULD BE ENOUGH TO KEEP HIGH TEMPERATURES A BIT COOLER THAN
YESTERDAY. THE DAYTIME CONVECTION...FUELED BY SOME UPPER LEVEL
HELP...LOW LIS...MODERATE CAPE...AND ABOVE NORMAL PWS...WILL DIE OFF
BY EARLY EVENING LEAVING A MUGGY AIR MASS BEHIND FOR THE NIGHT WITH
ONLY A SMALL RIDGE TO VALLEY DIFFERENCE EXPECTED...BUT MORE IN THE
WAY OF PATCHY FOG. SATURDAY WILL SEE THE APPROACH OF THE SYSTEM/S
MAIN COLD FRONT AND THIS SHOULD BE ENOUGH TO KICK OFF ADDITIONAL AIR
MASS SHOWERS AND STORMS GIVEN A SIMILAR THERMAL AND MOISTURE PROFILE
AS FRIDAY.
AGAIN USED THE CONSSHORT FOR TD AND WINDS THROUGH THE FIRST 24 HOURS
AS A STARTING POINT...WITH HIGHS A BIT LOWER THAN THURSDAY FOR BOTH
TODAY AND SATURDAY...WHILE USING THE CONSALL FOR A STARTING POINT
TONIGHT. AS FOR POPS...GENERALLY ENDED UP CLOSER TO THE HIGHER MET
NUMBERS THROUGHOUT THE SHORT TERM PORTION OF THE FORECAST.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 300 AM EDT FRI MAY 31 2013
A MID/UPPER LEVEL TROUGH WILL SWING ACROSS KENTUCKY SATURDAY NIGHT
INTO SUNDAY NIGHT...PRODUCING A PERIOD OF SHOWERS AND THUNDERSTORMS
FOR THE AREA. MODELS ARE ALL IN PRETTY DECENT AGREEMENT SO HAVE
INCREASED POPS FROM LATE SATURDAY NIGHT INTO SUNDAY. SEVERE THREAT
IS FAIRLY MINIMAL AS CLOUD COVER MAY LIMIT INSTABILITY AND SHEAR IS
QUITE WEAK. FRONT WILL DEPART TO THE SOUTH SUNDAY NIGHT...WITH RAIN
CHANCES DROPPING SOUTHEASTWARD. A COOLER AND LESS HUMID AIRMASS WILL
SETTLE INTO THE AREA FOR THE EARLY PORTION OF NEXT WEEK...ALLOWING
FOR VERY PLEASANT CONDITIONS FOR EARLY JUNE. ANOTHER RIDGE OF HIGH
PRESSURE WILL BUILD OVER THE SOUTHEAST BY THE MIDDLE TO LATE
PORTIONS OF NEXT WEEK WITH RETURN FLOW AGAIN ESTABLISHING ITSELF
OVER THE AREA. AS MOISTURE INCREASES BY MIDWEEK...RAIN CHANCES WILL
SLOWLY RAMP UP SIMILAR TO THIS PAST WEEK. TEMPERATURES WILL TURN
MILDER AS WELL AS THE WEEK GOES ON. MODELS ARE ALL IN DECENT
AGREEMENT THROUGH THE END OF NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 215 AM EDT FRI MAY 31 2013
HIGH PRESSURE ALONG THE EAST COAST WILL SLIDE SLOWLY EAST WHILE A
CENTER OF LOW PRESSURE CREEPS EAST THROUGH THE NORTHERN PLAINS
OVERNIGHT. A TROUGH OF LOW PRESSURE EXTENDING FROM THE NORTHERN
PLAINS LOW WILL SWING THROUGH THE MID MS VALLEY AND INTO THE GREAT
LAKES ON FRIDAY. THIS LOW PRESSURE TROUGH WILL BRING AN INCREASE IN
CLOUD COVER LATE TONIGHT AND INTO FRIDAY...BUT CEILINGS ACROSS THE
REGION WILL LIKELY REMAIN VFR. IT APPEARS THAT THE INITIAL SHOWERS
AND THUNDERSTORMS ASSOCIATED WITH THE LOW PRESSURE TROUGH WILL BE
DECAYING AS THEY MOVE EAST INTO EASTERN KY FRIDAY MORNING...BUT WOULD
NOT RULE OUT SOME OF THIS CONVECTION IMPACTING THE TAF SITES BY NOON.
THE EXACT TIMING AND LOCATION IS STILL UNCERTAIN...SO JUST WENT WITH
VCTS AT THIS TIME. THIS FIRST SURGE WILL DIE OUT BY EVENING AND
EXPECT THE CIGS TO SCATTER OUT. WINDS THROUGH THE PERIOD WILL BE
AROUND 10 KTS OR LESS...GENERALLY FROM THE SOUTH.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...KAS
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS CARIBOU ME
521 PM EDT FRI MAY 31 2013
.SYNOPSIS...
A COLD FRONT WILL DROP SOUTH INTO NORTHERN MAINE TONIGHT. THE
FRONT WILL LIFT BACK TO THE NORTH AS A WARM FRONT LATE SATURDAY
NIGHT. A STRONG COLD FRONT WILL APPROACH FROM THE WEST LATE IN THE
DAY SUNDAY AND VERY SLOWLY CROSS THE REGION SUNDAY NIGHT THROUGH
MONDAY NIGHT.
&&
.NEAR TERM /THROUGH SATURDAY/...
515 PM UPDATE: WE UPDATED POPS TO INCREASE TO CATEGORICAL RANGE
FOR NRN ME TO ACCOUNT FOR THE LN OF TSTMS MOVG IN FROM QB.
ENHANCED WORDING FOR DAMAGING WINDS...HAIL AND HEAVY DOWNPOURS
WERE INCLUDED TIL 11 PM...AT WHICH POINT...THE HRRR MODEL INDICATES
THAT MOST OF THE STRONG TSTM ELEMENTS WILL HAVE MOVED SE INTO NB.
ALSO UPDATED QPF FOR THE 18-24Z AND 00-06Z TM FRAMES TNGT TO
INCREASE TO CVR CONVECTIVE RNFL RATES WITH THIS LN. 1-3 HR FLASH
FLOOD GUIDANCE IS ONLY ABOUT 1.50 INCHES FOR MOST OF NRN ME...SO
WE WILL BE MONITORING FOR POSSIBLE LCLZD FLOODING AS WELL.
ORGNL DISC: A VERY WARM AND HUMID AIR MASS WILL REMAIN IN PLACE
THROUGH TONIGHT. A COLD FRONT WILL SAG SOUTHWARD OUT OF QUEBEC
INTO THE SAINT JOHN VALLEY THIS EVENING AND BRING THE THREAT OF
STRONG OR SEVERE THUNDERSTORMS WITH DAMAGING WINDS AND SMALL HAIL.
WITH STRONG WINDS ALOFT AND FAST STORM MOTIONS...SOME BOWING LINE
SEGMENTS ARE POSSIBLE AS THIS CONVECTION ENTERS THE NORTHERN END
OF THE CWA THIS EVENING. DOWNED TREES WERE ALREADY REPORTED WITH A
WEAKER THUNDERSTORM IN FORT KENT THIS AFTERNOON. DEEPER STORMS MAY
ALLOW FOR UP TO QUARTER SIZE HAIL BRIEFLY. WITH PWATS OVER ONE AND
HALF INCH...HEAVY DOWNPOURS ARE EXPECTED. THESE STORMS COULD REACH
40K FT. THE SEVERE WEATHER THREAT SHOULD BE RESTRICTED PRIMARILY
TO ZONES ONE AND TWO IN NORTHERN AROOSTOOK WITH STORMS WEAKENING
BY THE TIME THEY REACH HOULTON LATER THIS EVENING.
ELSEWHERE IN THE FORECAST AREA...AIR MASS THUNDERSTORMS WILL END
LATER THIS AFTERNOON AND A WARM AND HUMID NIGHT IS EXPECTED WITH
LOWS IN THE UPPER 60S FOR DOWN EAST AND AROUND BANGOR. LOWS WILL
BE IN THE LOW 60S TOWARDS THE CROWN OF MAINE. THE COLD FRONT WILL
STALL IN NORTHERN MAINE WITH CLOUD COVER AND THUNDERSTORMS
PERSISTING WELL INTO THE NIGHT.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
ACTIVE WEATHER IS EXPECTED DURING THE SHORT TERM WITH THE MAIN
CONCERNS THE POTENTIAL FOR STRONG TO SEVERE THUNDERSTORMS AND FLASH
FLOODING.
A FRONTAL BOUNDARY IS EXPECTED TO STRETCH ACROSS THE CENTRAL
PORTION OF THE CWA SAT EVENING. THE FRONT SHOULD LIFT BACK TO THE
NORTH AS A WARM FRONT SAT NIGHT AND SHOULD BE ACCOMPANIED BY
SHOWERS AND EMBEDDED THUNDERSTORMS...ESPECIALLY ACROSS THE
NORTHERN HALF OF THE AREA. PRECIPITABLE H20 IS PROGGED TO BE
AROUND 1.6-1.8 INCHES WHICH IS NEAR RECORD LEVELS FOR JUNE 1ST.
SHOWERS AND THUNDERSTORMS SAT NIGHT WILL HAVE THE POTENTIAL OF
PRODUCING HEAVY DOWNPOURS...AND DURING THE EVENING GUSTY WIND AND
SMALL HAIL. A STRONG COLD FRONT WILL APPROACH THE WESTERN BORDER
OF MAINE LATE IN THE DAY SUNDAY. THE MODELS DIFFER ON THE AMOUNT
OF INSTABILITY THAT WILL BE AVAILABLE SUN PM...AND MUCH WILL
DEPEND ON CLOUD COVER/PRE-EXISTING SHOWERS THAT COULD LIMIT JUST
HOW UNSTABLE IT BECOMES DURING THE AFTERNOON. THE MODELS DO
INDICATE ENOUGH CAPE AND SHEAR THAT SEVERE STORMS WILL BE POSSIBLE
DURING THE AFTERNOON/EVENING. THE HIGH PWATS ALSO MEAN THAT HEAVY
DOWNPOURS AND FLASH FLOODING WILL BE CONCERNS TOO...ESPECIALLY
GIVEN HOW SATURATED THE GROUND IS FROM THE RECENT HEAVY RAINS. THE
ENHANCED WORDING THAT THE MIDNIGHT CREW HAD IN LOOKS REAL GOOD AND
THE ONLY CHANGE WAS TO ADD THE LOCALLY HEAVY RAIN WORDING FOR SUN
PM/EVE. THE COLD FRONT IS EXPECTED TO ONLY VERY SLOWLY MOVE ACROSS
THE CWA SUN NIGHT AND MON AND MAY ONLY BE ON A HOULTON-BANGOR LINE
BY MON EVENING. THE BEST CHANCE OF SHOWERS AND THUNDERSTORMS
MONDAY WILL LIKELY BE ACROSS THE SOUTHEAST OF THE CWA WITH SOME
DRYING TO BEGIN TO WORK INTO THE WESTERN ZONES. WILL AGAIN MENTION
HEAVY RAIN POSSIBLE ACROSS THE SOUTHEAST HALF OF THE CWA. WILL
HOLD OFF ON ANY ENHANCED SEVERE WEATHER LANGUAGE AS IT IS IN DAY
THREE. THE SPC DOES HAVE MUCH OF THE AREA IN A SLIGHT RISK FOR DAY
3.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
THE EXTENDED MODELS CONTINUE TO BE IN GOOD AGREEMENT THROUGH THE
EARLY AND MID PORTIONS OF THE EXTENDED. A LOW PRESSURE SYSTEM SE
OF JAMES BAY...WITH AN ASSOCIATED FRONTAL SYSTEM EXTENDING SOUTH
THROUGH DOWNEAST MAINE...THEN SOUTH ALONG THE ATLANTIC COAST. A
BERMUDA HIGH PRESSURE SYSTEM RIDGED INTO THE COAST...A SECOND HIGH
PRESSURE SYSTEM BUILDING SE OUT OF WRN CANADA. BY THE START OF THE
EXTENDED PERIOD THE NRN PORTIONS OF THE FRONT CONTINUES TO REMAIN
UNDER THE UPPER LEVEL RIDGE...THE SRN PORTION HOWEVER WILL BEGIN
TO MOVE OUT AS THE UPPER TROUGH MOVES TO THE EAST SIDE OF THE
APPALACHIANS. BOTH MODELS INDICATE A SECONDARY LOW DEVELOPING
ALONG COAST VA WHICH WILL ASSIST WITH THE EASTWARD MOVEMENT OF
THE FRONT. BY WED MRNG THE FRONT WILL BE WELL EAST OF THE
AREA...AND HIGHER PRESSURE WILL BUILD INTO MAINE. THE HIGH
PRESSURE RIDGE WILL REMAIN IN PLACE THROUGH AT LEAST FRI MRNG. FRI
MRNG A NEW LOW PRESSURE SYSTEM WILL BE CENTERED OVER THE GREAT
LAKES...WITH ITS SUPPORTING UPPER LOW OVER CENTRAL MANITOBA. THE
GFS SHOWS A WARM FRONT EXTENDED EAST INTO WRN MAINE. THE ECMWF FRI
MRNG MAINTAINS THE HIGH PRESSURE RIDGE WITH NO APPARENT WARM FRONT
ASSOCIATED WITH THE FRONT. BY FRI EVENING THE ECMWF SYSTEM BECOMES
A BIT MORE ORGANIZED WITH ITS UPPER LOW MOVING TO SW JAMES BAY.
BY SAT MRNG BOTH MODELS MOVE THE SHOWERS ASSOCIATED WITH THE LOW
INTO MAINE.
STARTED WITH A BASE OF GMOS...OVER LAID A BLEND OF OFFICIAL/ALL
MODEL BLEND FOR WNDS/POPS/SKY/MAX/MIN. ADDED 15 PERCENT TO WINDS
FOR GUSTS OVER LAND...25 PERCENT TO WINDS OVER COASTAL WATERS.
&&
.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
NEAR TERM: VFR OUTSIDE OF THUNDERSTORMS LATE THIS AFTERNOON AND
EVENING. THUNDERSTORMS COULD BE SEVERE TOWARDS CAR...PQI AND FVE THIS
EVENING WITH DAMAGING WINDS AND SMALL HAIL. THE FRONT WILL STALL
AND COULD PRODUCE IFR VIS AND CIGS FROM PQI NORTHWARD INTO EARLY
SATURDAY MORNING. OTHERWISE...VFR CONDITIONS ARE EXPECTED.
SHORT TERM: VFR MUCH OF THE TIME SAT NIGHT THROUGH MONDAY...BUT A
PERIOD OF MVFR TO IFR POSSIBLE SAT NIGHT FROM KHUL NORTH IN SHOWERS
AND THUNDERSTORMS. ADDITIONAL PERIODS OF MVFR AND BRIEF IFR
POSSIBLE IN ANY NEAR CONVECTION SUN PM AND AGAIN MONDAY. STRONG AND
ERRATIC WIND GUSTS AND HAIL WILL BE POSSIBLE IN/NEAR THE STRONGEST
CONVECTION.
&&
.MARINE...
NEAR TERM: FOG IS EXPECTED TO RETURN LATER TONIGHT AND TOMORROW ON
THE WATERS. OTHERWISE...STABLE CONDITIONS MEAN LIGHT WINDS AND A
SOUTH SWELL AROUND 2 TO 3 FEET.
SHORT TERM: A SW WIND WILL PICK UP OUT AHEAD OF A COLD FRONT SUNDAY
AND MAY REACH SCA LEVELS BY SUN PM AND CONTINUE INTO MONDAY. THE
SEAS WILL LIKELY REACH SCA LEVELS BY SUNDAY AFTERNOON AND CONTINUE
INTO MONDAY WITH A SOUTH SWELL AND A COMBINED SEA/SWELL OF 8-10 FEET
EXPECTED BY SUNDAY NIGHT.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...VJN
SHORT TERM...CB
LONG TERM...NORTON
AVIATION...VJN/CB
MARINE...VJN/CB
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1233 PM EDT FRI MAY 31 2013
.SYNOPSIS...
A WARM RIDGE OF HIGH PRESSURE WILL BUILD REMAIN OVER MUCH OF THE
REGION INTO THE WEEKEND. A COLD FRONT WILL BRIEFLY SLIP SOUTHWARD
ACROSS NORTHERN AREAS LATER TONIGHT BEFORE PUSHING BACK TO THE
NORTHEAST AS A WARM FRONT LATE SATURDAY AND SATURDAY NIGHT. A STRONGER
COLD FRONT WILL CROSS THE REGION SUNDAY NIGHT THROUGH MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
1215PM UPDATE...
ADDED DAMAGING WINDS ZONES ONE AND TWO THIS EVENING. BOWING LINE
SEGMENTS ARE POSSIBLE. LATEST RUC/HRRR GUIDANCE SHOWING 50 KTS AT
H850 COINCIDENT WITH STORMS. SMALL HAIL IS ALSO POSSIBLE BUT WINDS
SHOULD BE REGARDED AS THE PRIMARY THREAT.
PREVIOUSLY INCREASED HIGHS FOR TODAY AND ADJUSTED LOWS TONIGHT.
ALSO ADJUSTED TODAY`S CLOUD COVER BASED ON TRENDS AND LATEST
GUIDANCE.
9AM UPDATE...
HAVE ADDED ENHANCED WORDING FOR LOCALLY HEAVY RAINFALL AND GUSTY
WINDS THIS AFTERNOON AND EVENING...MOSTLY FOR NORTHERN AROOSTOOK
COUNTY. AS A FRONTAL BOUNDARY SAGS SOUTHWARD THIS EVENING TOWARDS
THE SAINT JOHN VALLEY...THE COMBINATION OF DAYTIME HEATING...DEW
POINTS IN THE 60S AND SIGNIFICANT INSTABILITY TO THE TROP WILL
PRODUCE HEAVY THUNDERSTORMS. 12Z RAOBS FROM CAR AND MANIWAKI AS
WELL AS BUFKIT FORECAST SOUNDINGS SHOW A DEEP DRY LAYER FROM THE
SFC TO H800. AS A RESULT...WINDS ARE ASSESSED AS THE MOST SIGNIFICANT
THREAT BESIDES HEAVY DOWNPOURS. PWATS ARE OVER AN INCH AND A HALF.
THE HRRR SEEMS TO HAVE A REASONABLE HANDLE ON THE SITUATION WITH
STRONGER CELLS ENTERING THE SAINT JOHN VALLEY THIS EVENING.
635 AM UPDATE...WHAT`S LEFT OF THE ISOLATED TSTM THAT ENTERED THE
WESTERN MAINE BORDER NEAR DAAQUAM EARLIER THIS MORNING HAS BEEN
MOVING STEADILY SOUTHEAST AND WILL BE NEAR HOULTON SHORTLY. NOT
MUCH LTNG WITH THIS CELL AT THE MOMENT BUT WILL CONTINUE TO
MENTION ISOLATED THUNDER THIS MORNING...BUT THE BEST CHANCE FOR
THUNDER WILL BE THIS AFTERNOON. JUST SOME MINOR TWEAKS OTHERWISE
NO SIGNIFICANT CHANGES.
UNSEASONABLY WARM WEATHER CAN BE EXPECTED TODAY AS TEMPERATURES ARE
EXPECTED TO SOAR INTO THE LOW TO MID 80S ACROSS MOST OF NORTHERN AND
DOWNEAST MAINE TODAY. A COLD FRONT WILL APPROACH NORTHERN MOST MAINE
THIS AFTERNOON. THIS BOUNDARY WILL BE THE FOCUS FOR SCATTERED SHOWER
AND TSTM DEVELOPMENT...MAINLY THIS AFTERNOON. SB CAPE VALUES ARE
FORECASTED TO RANGE FROM 500 TO 1000 J/KG WITH EVEN HIGHER CAPE
VALUES ACROSS PORTIONS OF INTERIOR DOWNEAST MAINE WHERE MORE IN THE
WAY OF SURFACE HEATING IS EXPECTED.
DESPITE THE HIGHER CAPE VALUES THE BEST CHANCE OF ANY ORGANIZED
THUNDERSTORM DEVELOPMENT WILL BE ACROSS FAR NORTHERN MAINE AND
ESPECIALLY THE SAINT JOHN VALLEY WHERE THE APPROACHING BOUNDARY
WILL PROVIDE A FOCUS FOR CONVECTIVE DEVELOPMENT. ALTHOUGH WE ARE
EXPECTING ANY THUNDERSTORMS TO REMAIN BELOW SEVERE LIMITS AT THIS
TIME. ACROSS CENTRAL AND DOWNEAST MAINE EXPECT ISOLATED
THUNDERSTORMS.
EXPECT THE FRONTAL BOUNDARY TO SAG INTO NORTHERN MAINE OVERNIGHT AND
THIS WILL RESULT IN A CONTINUED CHANCE FOR SHOWERS AND PERHAPS A FEW
THUNDERSTORMS CONTINUING INTO THIS EVENING. PATCHY FOG WILL ALSO BE
POSSIBLE. LOWS TONIGHT WILL GENERALLY BE IN THE 60S.
NOTE: THE MAINE DEPARTMENT OF ENVIRONMENTAL PROTECTION HAS ISSUED AN
AIR QUALITY ALERT FOR THE DOWNEAST COAST FOR UNHEALTHY FOR SENSITIVE
GROUPS DUE TO OZONE. THIS ALERT IS IN EFFECT FRO 11 AM UNTIL 11 PM
TONIGHT.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
NOT MUCH CHANGE FROM PREVIOUS THINKING AS MODELS REMAIN VRY
CONSISTENT W/ THEIR GUIDANCE THRU THIS PD... BACK DOOR COLD FRONT
STILL EXPECTED TO STALL FROM NW-SE MAINE SAT AM THEN LIFT NEWRD AS
A WARM FRONT LATE SAT THRU SAT NGT. WILL KEEP HIGHEST POPS (CHC TO
LOW LIKELY POPS) ACROSS THE CENTRAL AND N THRU SAT NGT FOR SHOWERS
AND OCNL THUNDER AS VRY WARM AND UNSTABLE AIR W AND SW OF THIS
FRONT OVERRUNS THIS BNDRY. THIS FRONT SHOULD ALSO CREATE A RATHER
DECENT NE-SW THERMAL GRADIENT ACROSS THE REGION W/ COOLEST TEMPS
FAR NERN AREAS WHERE CLD/SHOWERS AND BEING ON THE COOL SIDE OF THE
BNDRY SHOULD KEEP MAXES ON SAT IN THE LOWER-MID 70S WHILE OUR FAR
SWRN AREAS IN THE WARM AND HUMID AIRMASS COULD SEE TEMPS INTO THE
UPPER 80S OR EVEN TO 90 DEPENDING ON CLD CVR. BY LATE SAT NGT/ERLY
SUN AM...ALL AREAS BACK INTO THE WARM AND STICKY AIR W/ A STRONG
COLD FRONT THEN FCST TO APPROACH OUR FAR WRN/NWRN AREAS LATER SUN
AFTN. SFC-BASED CAPES OF 1500-2500 J/KG...MDT SHEAR AHEAD OF A
STRONG COLD FRONT SUGGESTS AN ELEVATED THREAT OF STRONG TO PSBLY
SEVERE STORMS SPCLY OUR WRN/NWRN AREAS FOR SUN AFTN. WILL CONT
ENHANCED WORDING AND CONTD MENTION IN THE HWO. FLASH FLOODING
RISKS REMAIN A CONCERN AS WELL W/ THE HVY RAINS AND SATURATED
SOIL FROM THIS PAST WEEKEND...
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
THE STRONG COLD FRONT ADDRESSED IN THE SHORT TERM SECTION ABV IS
FCST TO SLOWLY CROSS THE FA SUN NGT THRU MON AND EXIT OUR FAR
SERN AREAS BY ERLY TUE AM. THIS SLOW TRANSITION ACROSS THE FCST
AREA SUGGESTS AN ELEVATED THREAT FOR CONVECTION ACROSS OUR SERN
AREAS MON AFTN AND HAVE CARRIED LIKELY POPS FOR SHOWERS/TSTMS MON
AFTN OUR SERN ZNS... OTHERWISE...GRADUALLY COOLER AND DRIER AIR
IS FCST TO OVERSPREAD THE AREA THRU THE PD AS COOL CANADIAN HIGH
PRES BUILD INTO THE REGION. WILL KEEP MENTION OF SHOWERS ACROSS
THE N TUE AFTN AS A COLD UPPER TROF SWINGS EWRD ACROSS THE AREA...
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
NEAR TERM: VFR THIS MORNING WITH SOME LOCAL MVFR IN PATCHY FOG.
MAINLY VFR THIS AFTERNOON AND TONIGHT EXCEPT LCL MVFR IN SCATTERED
SHOWERS AND TSTMS.
SHORT TERM: MVFR TO PSBL IFR CONDS ACROSS THE NRN TAF SITES
SAT/SAT NGT IN SHOWERS/OCNL THUNDER ASSOCIATED W/ A FRONTAL BNDRY
WHICH WILL EVENTUALLY LIFT NE OF THE AREA BY LATER SAT NGT THEN
ANOTHER ROUND OF MVFR TO BRIEF IFR W/ SHOWERS/TSTMS LATER SUN AFTN
AS A STRONG COLD FRONT APPROACHES.
FOR THE SRN TAF SITES...EXPECT MAINLY VFR CONDS W/ SOME PSBL LATE
NGT/ERLY AM FOG SAT NGT. MVFR TO BRIEF IFR CONDS EXPECTED LATE SUN
INTO MON AS A STRONG COLD FRONT APPROACHES THEN CROSSES THESE AREAS...
&&
.MARINE...
NEAR TERM: WINDS/SEAS WILL REMAIN BELOW SCA LEVELS THROUGH TONIGHT.
SHORT TERM: WARM RIDGE OF HIGH PRES ACROSS THE WATERS THRU THE PD
WILL KEEP RATHER STABLE CONDS IN PLACE INTO SUN. BY LATER
SUN...DESPITE THIS STABILITY...A STRONG APPROACHING COLD FRONT MAY
ALLOW WND GUSTS TO REACH MARGINAL SCA LEVELS. SEAS MAY ALSO
INCREASE TO MARGINAL SCA LEVELS IN PERSISTENT SW FLOW IN ADVANCE
OF THIS APPROACHING FRONT BY LATER SUN...
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...DUDA/MCW
SHORT TERM...KHW
LONG TERM...KHW
AVIATION...DUDA/MCW/KHW
MARINE...DUDA/MCW/KHW
AREA FORECAST DISCUSSION
NWS CARIBOU ME
926 AM EDT FRI MAY 31 2013
.SYNOPSIS...
A WARM RIDGE OF HIGH PRESSURE WILL BUILD REMAIN OVER MUCH OF THE
REGION INTO THE WEEKEND. A COLD FRONT WILL BRIEFLY SLIP SOUTHWARD
ACROSS NORTHERN AREAS LATER TONIGHT BEFORE PUSHING BACK TO THE
NORTHEAST AS A WARM FRONT LATE SATURDAY AND SATURDAY NIGHT. A STRONGER
COLD FRONT WILL CROSS THE REGION SUNDAY NIGHT THROUGH MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
9AM UPDATE...
HAVE ADDED ENHANCED WORDING FOR LOCALLY HEAVY RAINFALL AND GUSTY
WINDS THIS AFTERNOON AND EVENING...MOSTLY FOR NORTHERN AROOSTOOK
COUNTY. AS A FRONTAL BOUNDARY SAGS SOUTHWARD THIS EVENING TOWARDS
THE SAINT JOHN VALLEY...THE COMBINATION OF DAYTIME HEATING...DEW
POINTS IN THE 60S AND SIGNIFICANT INSTABILITY TO THE TROP WILL
PRODUCE HEAVY THUNDERSTORMS. 12Z RAOBS FROM CAR AND MANIWAKI AS
WELL AS BUFKIT FORECAST SOUNDINGS SHOW A DEEP DRY LAYER FROM THE
SFC TO H800. AS A RESULT...WINDS ARE ASSESSED AS THE MOST SIGNIFICANT
THREAT BESIDES HEAVY DOWNPOURS. PWATS ARE OVER AN INCH AND A HALF.
THE HRRR SEEMS TO HAVE A REASONABLE HANDLE ON THE SITUATION WITH
STRONGER CELLS ENTERING THE SAINT JOHN VALLEY THIS EVENING.
635 AM UPDATE...WHAT`S LEFT OF THE ISOLATED TSTM THAT ENTERED THE
WESTERN MAINE BORDER NEAR DAAQUAM EARLIER THIS MORNING HAS BEEN
MOVING STEADILY SOUTHEAST AND WILL BE NEAR HOULTON SHORTLY. NOT
MUCH LTNG WITH THIS CELL AT THE MOMENT BUT WILL CONTINUE TO
MENTION ISOLATED THUNDER THIS MORNING...BUT THE BEST CHANCE FOR
THUNDER WILL BE THIS AFTERNOON. JUST SOME MINOR TWEAKS OTHERWISE
NO SIGNIFICANT CHANGES.
UNSEASONABLY WARM WEATHER CAN BE EXPECTED TODAY AS TEMPERATURES ARE
EXPECTED TO SOAR INTO THE LOW TO MID 80S ACROSS MOST OF NORTHERN AND
DOWNEAST MAINE TODAY. A COLD FRONT WILL APPROACH NORTHERN MOST MAINE
THIS AFTERNOON. THIS BOUNDARY WILL BE THE FOCUS FOR SCATTERED SHOWER
AND TSTM DEVELOPMENT...MAINLY THIS AFTERNOON. SB CAPE VALUES ARE
FORECASTED TO RANGE FROM 500 TO 1000 J/KG WITH EVEN HIGHER CAPE
VALUES ACROSS PORTIONS OF INTERIOR DOWNEAST MAINE WHERE MORE IN THE
WAY OF SURFACE HEATING IS EXPECTED.
DESPITE THE HIGHER CAPE VALUES THE BEST CHANCE OF ANY ORGANIZED
THUNDERSTORM DEVELOPMENT WILL BE ACROSS FAR NORTHERN MAINE AND
ESPECIALLY THE SAINT JOHN VALLEY WHERE THE APPROACHING BOUNDARY
WILL PROVIDE A FOCUS FOR CONVECTIVE DEVELOPMENT. ALTHOUGH WE ARE
EXPECTING ANY THUNDERSTORMS TO REMAIN BELOW SEVERE LIMITS AT THIS
TIME. ACROSS CENTRAL AND DOWNEAST MAINE EXPECT ISOLATED
THUNDERSTORMS.
EXPECT THE FRONTAL BOUNDARY TO SAG INTO NORTHERN MAINE OVERNIGHT AND
THIS WILL RESULT IN A CONTINUED CHANCE FOR SHOWERS AND PERHAPS A FEW
THUNDERSTORMS CONTINUING INTO THIS EVENING. PATCHY FOG WILL ALSO BE
POSSIBLE. LOWS TONIGHT WILL GENERALLY BE IN THE 60S.
NOTE: THE MAINE DEPARTMENT OF ENVIRONMENTAL PROTECTION HAS ISSUED AN
AIR QUALITY ALERT FOR THE DOWNEAST COAST FOR UNHEALTHY FOR SENSITIVE
GROUPS DUE TO OZONE. THIS ALERT IS IN EFFECT FRO 11 AM UNTIL 11 PM
TONIGHT.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
NOT MUCH CHANGE FROM PREVIOUS THINKING AS MODELS REMAIN VRY
CONSISTENT W/ THEIR GUIDANCE THRU THIS PD... BACK DOOR COLD FRONT
STILL EXPECTED TO STALL FROM NW-SE MAINE SAT AM THEN LIFT NEWRD AS
A WARM FRONT LATE SAT THRU SAT NGT. WILL KEEP HIGHEST POPS (CHC TO
LOW LIKELY POPS) ACROSS THE CENTRAL AND N THRU SAT NGT FOR SHOWERS
AND OCNL THUNDER AS VRY WARM AND UNSTABLE AIR W AND SW OF THIS
FRONT OVERRUNS THIS BNDRY. THIS FRONT SHOULD ALSO CREATE A RATHER
DECENT NE-SW THERMAL GRADIENT ACROSS THE REGION W/ COOLEST TEMPS
FAR NERN AREAS WHERE CLD/SHOWERS AND BEING ON THE COOL SIDE OF THE
BNDRY SHOULD KEEP MAXES ON SAT IN THE LOWER-MID 70S WHILE OUR FAR
SWRN AREAS IN THE WARM AND HUMID AIRMASS COULD SEE TEMPS INTO THE
UPPER 80S OR EVEN TO 90 DEPENDING ON CLD CVR. BY LATE SAT NGT/ERLY
SUN AM...ALL AREAS BACK INTO THE WARM AND STICKY AIR W/ A STRONG
COLD FRONT THEN FCST TO APPROACH OUR FAR WRN/NWRN AREAS LATER SUN
AFTN. SFC-BASED CAPES OF 1500-2500 J/KG...MDT SHEAR AHEAD OF A
STRONG COLD FRONT SUGGESTS AN ELEVATED THREAT OF STRONG TO PSBLY
SEVERE STORMS SPCLY OUR WRN/NWRN AREAS FOR SUN AFTN. WILL CONT
ENHANCED WORDING AND CONTD MENTION IN THE HWO. FLASH FLOODING
RISKS REMAIN A CONCERN AS WELL W/ THE HVY RAINS AND SATURATED
SOIL FROM THIS PAST WEEKEND...
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
THE STRONG COLD FRONT ADDRESSED IN THE SHORT TERM SECTION ABV IS
FCST TO SLOWLY CROSS THE FA SUN NGT THRU MON AND EXIT OUR FAR
SERN AREAS BY ERLY TUE AM. THIS SLOW TRANSITION ACROSS THE FCST
AREA SUGGESTS AN ELEVATED THREAT FOR CONVECTION ACROSS OUR SERN
AREAS MON AFTN AND HAVE CARRIED LIKELY POPS FOR SHOWERS/TSTMS MON
AFTN OUR SERN ZNS... OTHERWISE...GRADUALLY COOLER AND DRIER AIR
IS FCST TO OVERSPREAD THE AREA THRU THE PD AS COOL CANADIAN HIGH
PRES BUILD INTO THE REGION. WILL KEEP MENTION OF SHOWERS ACROSS
THE N TUE AFTN AS A COLD UPPER TROF SWINGS EWRD ACROSS THE AREA...
&&
.AVIATION /13Z FRIDAY THROUGH TUESDAY/...
NEAR TERM: VFR THIS MORNING WITH SOME LOCAL MVFR IN PATCHY FOG.
MAINLY VFR THIS AFTERNOON AND TONIGHT EXCEPT LCL MVFR IN SCATTERED
SHOWERS AND TSTMS.
SHORT TERM: MVFR TO PSBL IFR CONDS ACROSS THE NRN TAF SITES
SAT/SAT NGT IN SHOWERS/OCNL THUNDER ASSOCIATED W/ A FRONTAL BNDRY
WHICH WILL EVENTUALLY LIFT NE OF THE AREA BY LATER SAT NGT THEN
ANOTHER ROUND OF MVFR TO BRIEF IFR W/ SHOWERS/TSTMS LATER SUN AFTN
AS A STRONG COLD FRONT APPROACHES.
FOR THE SRN TAF SITES...EXPECT MAINLY VFR CONDS W/ SOME PSBL LATE
NGT/ERLY AM FOG SAT NGT. MVFR TO BRIEF IFR CONDS EXPECTED LATE SUN
INTO MON AS A STRONG COLD FRONT APPROACHES THEN CROSSES THESE AREAS...
&&
.MARINE...
NEAR TERM: WINDS/SEAS WILL REMAIN BELOW SCA LEVELS THROUGH TONIGHT.
SHORT TERM: WARM RIDGE OF HIGH PRES ACROSS THE WATERS THRU THE PD
WILL KEEP RATHER STABLE CONDS IN PLACE INTO SUN. BY LATER
SUN...DESPITE THIS STABILITY...A STRONG APPROACHING COLD FRONT MAY
ALLOW WND GUSTS TO REACH MARGINAL SCA LEVELS. SEAS MAY ALSO
INCREASE TO MARGINAL SCA LEVELS IN PERSISTENT SW FLOW IN ADVANCE
OF THIS APPROACHING FRONT BY LATER SUN...
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...DUDA/MCW
SHORT TERM...KHW
LONG TERM...KHW
AVIATION...DUDA/MCW/KHW
MARINE...DUDA/MCW/KHW
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
214 PM EDT FRI MAY 31 2013
.SYNOPSIS...
HIGH PRESSURE REMAINS ANCHORED OFF THE MID ATLANTIC COAST THROUGH
SUNDAY. A COLD FRONT WILL BRING INCREASING RAIN CHANCES...AS IT
SLOWLY CROSSES THE AREA ON MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
VERY SIMILAR DAY WXWISE TO THU ON THE WAY FOR TODAY. EXPECTING
ANOTHER VERY WARM DAY, AS THE SFC RIDGE AND STRENGTHENING H5 RIDGE
ALOFT REMAINS QUASI- STATIONARY WELL OFFSHORE.
DRY WEATHER CONTINUES TODAY WITH PERSISTENT WARM/STABLE AIR ALOFT
AND A LACK OF AVAILABLE TRIGGERS FOR LIFT. HIGH-RES MODELS
(SPECIFICALLY THE HRRR AND SPC WRF) AGAIN PICKING UP THE THE
POTENTIAL FOR AN ISOLATED SHOWER OR TWO BLOWING UP ON AFTN
SEABREEZE OVER THE FAR SOUTHEAST PART OF THE CWA (AND ALSO ALONG
THE MASON-DIXON IN ASSN WITH A WEAK, SHEARED OUT SHORTWAVE
CROSSING WELL NORTH OF THE AKQ CWA). AS WITH YESTERDAY THOUGH,
RAIN CHC ACROSS LOCAL AREA REMAINS TOO SMALL TO INCLUDE POPS IN
THE FORECAST. THUS, HV CONTINUED TO CAP RAIN CHANCES AT 10% OR
LESS. HIGH TEMPERATURES AWAY FROM THE IMMEDIATE COAST AGAIN
GENERALLY ~90/L90S INLAND, LOW TO MID 80S AT IMMEDIATE COASTAL
AREAS.
CLEAR AND MILD OVERNIGHT...EARLY MORNING LOWS SAT MORNING IN THE
U60S TO NR 70.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
GRADUALLY WEAKENING H5 RIDGE OFF THE MID ATLANTIC COAST SHIFTS
SLIGHTLY TO THE EAST SATURDAY AND SUNDAY AHEAD OF APPROACHING
MID-LVL TROUGH, WHICH PUSHES FROM THE NORTHERN PLAINS TOWARDS THE
UPR GRT LAKES ON SUNDAY. HOWEVER, SFC/UPR LEVEL RIDGING OFFSHORE
WL REMAIN THE DOMINATE WX FEATURE THRU THE WEEKEND, BRINGING
CONTINUED SUMMER-LIKE CONDITIONS. LTL (IF ANY) TRIGGER EXISTS FOR
CONVECTION ON SAT, AS AIRMASS REMAINS LARGELY CAPPED. FCST
REMAINS DRY AS BEST CHCS FOR ANY CONVECTION WILL AGAIN BE CONFINED
OVER THE MTNS. HIGHS SAT IN THE U80S-L90S, THOUGH AGAIN COOLER AT
THE BEACHES DUE TO LCL AFTN SEA BREEZE EFFECTS.
PARTLY TO MOSTLY CLEAR SKY FOR MOST OF SAT NIGHT, THOUGH WL NEED
TO WATCH GFS, AS IT CONTINUES TO KEY IN ON POTENTIAL FOR SOME LOW
STRATUS OVER THE I-85 CORRIDOR BACK INTO THE CENTRAL NC PIEDMONT
LATE. ERY MORNING LOWS SUNDAY MORNING IN THE M-U60S.
AFTER ANY LINGERING STRATUS QUICKLY LIFTS/ERODES SUNDAY MORNING,
THE DAY STARTS OUT MAINLY SUNNY. HOWEVER, CLOUDS LOOK TO INCREASE
FROM THE WEST BY SUN AFTN AHEAD OF APPROACHING FRONTAL BOUNDARY.
SLIGHT CHC TO LOW CHC POPS STILL LOOK GOOD BY MID AFTN SUNDAY AS
TSRAS LOOK TO FIRE ALONG PRE-FRONTAL/LEE TROUGHING TO THE WEST AND
PUSH E-NE ACROSS OUR WESTERN TIER OF COUNTIES (WEST OF RIC) LATE
SUN AFTN. MORE IN THE WAY OF CLOUD COVER WILL BE BALANCED OUT BY
STRONG COMPRESSIONAL HEATING AHEAD OF THE FRONT, AGAIN YIELDING
HIGHS IN THE U80S TO NR 90. GIVEN DP TEMPS IN THE L-M60S (HIGHEST
JUST BEFORE DIURNAL MIXING KICKS IN JUST AFTER 12Z)...HEAT INDEX
VALUES XPCTD TO REMAIN WITHIN A DEGREE OR TWO OF ACTUAL TEMPS BOTH
DAYS.
ECMWF/GFS IN PRETTY GOOD AGREEMENT REGARDING FROPA/PCPN TIMING FOR
SUNDAY NIGHT AND MONDAY. FRONT SLOWLY APPROACHES, AND BEGINS TO
PUSH ACROSS THE WESTERN THIRD OF THE LOCAL AREA LATE SUNDAY
NIGHT/MONDAY MORNING. DUE TO THE LATE NIGHT/ERY MORNING TIMING,
INSTABILITY ATTM LOOKS TO BE MARGINAL AT BEST, SO WILL GO WITH ISO
T WORDING FOR NOW. STILL, AS PW VALUES SHOOT UPWARDS OF 1.75"
AREA-WIDE SUNDAY NIGHT, RAIN CHANCES ARE LOOKING INCREASINGLY
FAVORABLE ACROSS THE PIEDMONT AFTER 00Z MON/8PM SUNDAY NIGHT.
THUS, WL GO WITH LKLY POP WEST OF I-95 LT SUNDAY NIGHT, WITH CHCS
INCREASING FARTHER EAST AFTER MIDNIGHT THRU DAWN MONDAY MORNING.
GIVEN THE CONSIDERABLE CLDS/PCPN, WL GO CLOSER TO EURO STATISTICAL
GUIDANCE, WHICH IS ABT A CATEGORY ABOVE 00Z/31 MEX NUMBERS. ERY
MORNING LOWS MON MORNING RIGHT AROUND 70/LOW 70S.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
LONG TERM PERIOD BEGINS W/ THE FRONT SLOWLY MOVING ACRS THE AREA
MON, WITH SHRAS/TSTMS EXPECTED ACROSS THE AREA. ALTHO WAA IS
WEAK...DEEP LAYER MOISTURE...MID-LVL S/W ENERGY AND UPR-LVL
DIVERGENCE CONTINUE TO WARRANT LIKELY POPS...CONTINUING INTO SE
AREAS MON NGT. GIVEN THE RAIN AND CLDS...TEMPS MON WILL MAX OUT IN
THE UPR 70S TO MID 80S. THE RAIN WILL END FROM W TO E EARLY TUE AS
THE FRONT SLIDES OFFSHORE. SFC HI PRES THEN BLDS IN FROM THE
NW...WITH HIGHS ONLY IN THE UPR 70S TO LO 80S ON TUE AND WED.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
HIGH PRESSURE OFF THE COAST CONTINUES TO BRING A STRONG FETCH OF S-SW
WINDS TO THE REGION. SATELLITE SHOWS A LARGE FIELD OF FAIR WX CU
FROM FL TO VA WITH THE FLOW AROUND THE HIGH. WINDS MIGHT BE A
LITTLE GUSTY DURING THE AFTN AND EARLY EVENING 15-20 KT...BUT
SHOULD DIMINISH AFTER SUNSET. NO SIGNIFICANT WX EXPECTED OVER THE
NEXT 24-36 HOURS BUT THE AMOUNT OF LOW LEVEL MOISTURE MAY DEVELOP
INTO SOME STRATUS CIGS DURING THE OVERNIGHT...SO OPTED TO SHOW
CIGS OF 010-035 FT OVER TAF SITES AND SOME MVFR VIS WITH PTCHY
FOG. ONLY LOW TO MODERATE CONFIDENCE THAT THE CIGS OR VIS WILL BE
WIDESPREAD.
OUTLOOK...THERE WILL BE A BETTER CHANCE FOR MVFR/IFR FOG OR
STRATUS SUNDAY MORNING. ISOLATED THUNDERSTORMS WILL BE PSBL SUNDAY
EVENING. THE CHANCES INCREASE MONDAY AHEAD OF AN APPROACHING COLD
FRONT. DRY/VFR CONDITIONS RETURN BY TUESDAY.
&&
.MARINE...
WINDS WILL CONTINUE TO BE GENERALLY FROM THE SOUTH THROUGH THE
WEEKEND. WIND SPEEDS AT ELEVATED SITES ARE RUNNING SEVERAL KNOTS
HIGHER THAN THOSE NEAR THE SURFACE OF THE WATER DUE TO POOR MIXING
WITH THE COLD WATER. THIS SHOULD CONTINUE TO BE THE CASE THROUGH THE
WEEKEND.
CONDITIONS SHOULD REMAIN BELOW SCA CRITERIA THROUGH THE DAY
SATURDAY. SOUTHERLY WINDS MAY GAIN ENOUGH SOUTHERLY FETCH TO PRODUCE
MARGINAL 5 FOOT SEAS OVER THE NORTHERN COASTAL WATERS BY SATURDAY
NIGHT. HOWEVER...THE MAIN SCA EVENT SHOULD BEGIN SUNDAY NIGHT OVER
THE COASTAL WATERS NORTH OF CAPE CHARLES. ELSEWHERE...CONDITIONS
SHOULD BE JUST SHORT OF SCA AS A COLD FRONT APPROACHES THE REGION.
THE FRONT MOVES SLOWLY TO THE EAST MONDAY NIGHT AND TUESDAY. PRESENT
INDICATIONS ARE THAT THE POST FRONTAL ENVIRONMENT WILL FAIL TO
PRODUCE SCA BUT THIS MAY CHANGE.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...AIR QUALITY ALERT UNTIL MIDNIGHT EDT TONIGHT FOR MDZ021>024.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MAM
NEAR TERM...MAM
SHORT TERM...MPR/MAM
LONG TERM...MAS
AVIATION...JEF
MARINE...LSA
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
709 AM EDT FRI MAY 31 2013
.SYNOPSIS...
HIGH PRESSURE REMAINS ANCHORED OFF THE MID ATLANTIC COAST THROUGH
SUNDAY. A COLD FRONT WILL BRING INCREASING RAIN CHANCES...AS IT
SLOWLY CROSSES THE AREA ON MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
VERY SIMILAR DAY WXWISE TO THU ON THE WAY FOR TODAY. EXPECTING
ANOTHER VERY WARM DAY, AS THE SFC RIDGE AND STRENGTHENING H5 RIDGE
ALOFT REMAINS QUASI- STATIONARY WELL OFFSHORE.
DRY WEATHER CONTINUES TODAY WITH PERSISTENT WARM/STABLE AIR ALOFT
AND A LACK OF AVAILABLE TRIGGERS FOR LIFT. HIGH-RES MODELS
(SPECIFICALLY THE HRRR AND SPC WRF) AGAIN PICKING UP THE THE
POTENTIAL FOR AN ISOLATED SHOWER OR TWO BLOWING UP ON AFTN
SEABREEZE OVER THE FAR SOUTHEAST PART OF THE CWA (AND ALSO ALONG
THE MASON-DIXON IN ASSN WITH A WEAK, SHEARED OUT SHORTWAVE
CROSSING WELL NORTH OF THE AKQ CWA). AS WITH YESTERDAY THOUGH,
RAIN CHC ACROSS LOCAL AREA REMAINS TOO SMALL TO INCLUDE POPS IN
THE FORECAST. THUS, HV CONTINUED TO CAP RAIN CHANCES AT 10% OR
LESS. HIGH TEMPERATURES AWAY FROM THE IMMEDIATE COAST AGAIN
GENERALLY ~90/L90S INLAND, LOW TO MID 80S AT IMMEDIATE COASTAL
AREAS.
CLEAR AND MILD OVERNIGHT...EARLY MORNING LOWS SAT MORNING IN THE
U60S TO NR 70.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
GRADUALLY WEAKENING H5 RIDGE OFF THE MID ATLANTIC COAST SHIFTS
SLIGHTLY TO THE EAST SATURDAY AND SUNDAY AHEAD OF APPROACHING
MID-LVL TROUGH, WHICH PUSHES FROM THE NORTHERN PLAINS TOWARDS THE
UPR GRT LAKES ON SUNDAY. HOWEVER, SFC/UPR LEVEL RIDGING OFFSHORE
WL REMAIN THE DOMINATE WX FEATURE THRU THE WEEKEND, BRINGING
CONTINUED SUMMER-LIKE CONDITIONS. LTL (IF ANY) TRIGGER EXISTS FOR
CONVECTION ON SAT, AS AIRMASS REMAINS LARGELY CAPPED. FCST
REMAINS DRY AS BEST CHCS FOR ANY CONVECTION WILL AGAIN BE CONFINED
OVER THE MTNS. HIGHS SAT IN THE U80S-L90S, THOUGH AGAIN COOLER AT
THE BEACHES DUE TO LCL AFTN SEA BREEZE EFFECTS.
PARTLY TO MOSTLY CLEAR SKY FOR MOST OF SAT NIGHT, THOUGH WL NEED
TO WATCH GFS, AS IT CONTINUES TO KEY IN ON POTENTIAL FOR SOME LOW
STRATUS OVER THE I-85 CORRIDOR BACK INTO THE CENTRAL NC PIEDMONT
LATE. ERY MORNING LOWS SUNDAY MORNING IN THE M-U60S.
AFTER ANY LINGERING STRATUS QUICKLY LIFTS/ERODES SUNDAY MORNING,
THE DAY STARTS OUT MAINLY SUNNY. HOWEVER, CLOUDS LOOK TO INCREASE
FROM THE WEST BY SUN AFTN AHEAD OF APPROACHING FRONTAL BOUNDARY.
SLIGHT CHC TO LOW CHC POPS STILL LOOK GOOD BY MID AFTN SUNDAY AS
TSRAS LOOK TO FIRE ALONG PRE-FRONTAL/LEE TROUGHING TO THE WEST AND
PUSH E-NE ACROSS OUR WESTERN TIER OF COUNTIES (WEST OF RIC) LATE
SUN AFTN. MORE IN THE WAY OF CLOUD COVER WILL BE BALANCED OUT BY
STRONG COMPRESSIONAL HEATING AHEAD OF THE FRONT, AGAIN YIELDING
HIGHS IN THE U80S TO NR 90. GIVEN DP TEMPS IN THE L-M60S (HIGHEST
JUST BEFORE DIURNAL MIXING KICKS IN JUST AFTER 12Z)...HEAT INDEX
VALUES XPCTD TO REMAIN WITHIN A DEGREE OR TWO OF ACTUAL TEMPS BOTH
DAYS.
ECMWF/GFS IN PRETTY GOOD AGREEMENT REGARDING FROPA/PCPN TIMING FOR
SUNDAY NIGHT AND MONDAY. FRONT SLOWLY APPROACHES, AND BEGINS TO
PUSH ACROSS THE WESTERN THIRD OF THE LOCAL AREA LATE SUNDAY
NIGHT/MONDAY MORNING. DUE TO THE LATE NIGHT/ERY MORNING TIMING,
INSTABILITY ATTM LOOKS TO BE MARGINAL AT BEST, SO WILL GO WITH ISO
T WORDING FOR NOW. STILL, AS PW VALUES SHOOT UPWARDS OF 1.75"
AREA-WIDE SUNDAY NIGHT, RAIN CHANCES ARE LOOKING INCREASINGLY
FAVORABLE ACROSS THE PIEDMONT AFTER 00Z MON/8PM SUNDAY NIGHT.
THUS, WL GO WITH LKLY POP WEST OF I-95 LT SUNDAY NIGHT, WITH CHCS
INCREASING FARTHER EAST AFTER MIDNIGHT THRU DAWN MONDAY MORNING.
GIVEN THE CONSIDERABLE CLDS/PCPN, WL GO CLOSER TO EURO STATISTICAL
GUIDANCE, WHICH IS ABT A CATEGORY ABOVE 00Z/31 MEX NUMBERS. ERY
MORNING LOWS MON MORNING RIGHT AROUND 70/LOW 70S.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
LONG TERM PERIOD BEGINS W/ THE FRONT SLOWLY MOVING ACRS THE AREA
MON, WITH SHRAS/TSTMS EXPECTED ACROSS THE AREA. ALTHO WAA IS
WEAK...DEEP LAYER MOISTURE...MID-LVL S/W ENERGY AND UPR-LVL
DIVERGENCE CONTINUE TO WARRANT LIKELY POPS...CONTINUING INTO SE
AREAS MON NGT. GIVEN THE RAIN AND CLDS...TEMPS MON WILL MAX OUT IN
THE UPR 70S TO MID 80S. THE RAIN WILL END FROM W TO E EARLY TUE AS
THE FRONT SLIDES OFFSHORE. SFC HI PRES THEN BLDS IN FROM THE
NW...WITH HIGHS ONLY IN THE UPR 70S TO LO 80S ON TUE AND WED.
&&
.AVIATION /11Z FRIDAY THROUGH TUESDAY/...
MAINLY S-SW WINDS ARE EXPECTED TO CONTINUE FOR THE 12Z TAF PERIOD
WITH ONE POSSIBLE EXCEPTION. WINDS AT ORF MAY BE INFLUENCED ONCE
AGAIN BY A BAY BREEZE AS SYNOPTIC WINDS WILL BE A BIT LIGHTER THAN
ON THURSDAY. MODELS ARE NOT CLEAR ON THE DIRECTION AND WENT VRBL
AND LIGHT. NO SUBSTANTIAL CLOUDINESS IS INDICATED SO KEPT SKC
THROUGH THE PERIOD.
SOME LOCATIONS OTHER THAN THE TAF SITES REPORTED PATCHY FOG THIS
MORNING. WITH THE COLUMN SLOWLY MOISTENING WITH TIME...FOG DEVELOP
SATURDAY MORNING AT SOME OF THE TAF SITES WHERE WINDS DIMINISH
SUFFICIENTLY. INCLUDED 4 MILES AT RIC FOR NOW AFT 09Z. WINDS MAY
BE TOO STRONG AT THE OTHER FOUR SITES BUT THIS WILL NEED TO
MONITORED. CONFIDENCE IS LOW FOR THE MVFR STRATUS THAT MAV MOS HAS
FOR ECG.
OUTLOOK...THERE WILL BE A BETTER CHANCE FOR MVFR/IFR FOG OR
STRATUS SUNDAY MORNING. ISOLATED THUNDERSTORMS WILL BE PSBL
SUNDAY EVENING. THE CHANCES INCREASE MONDAY AHEAD OF AN
APPROACHING COLD FRONT. DRY/VFR CONDITIONS RETURN BY TUESDAY.
&&
.MARINE...
WINDS WILL CONTINUE TO BE GENERALLY FROM THE SOUTH THROUGH THE
WEEKEND. WIND SPEEDS AT ELEVATED SITES ARE RUNNING SEVERAL KNOTS
HIGHER THAN THOSE NEAR THE SURFACE OF THE WATER DUE TO POOR MIXING
WITH THE COLD WATER. THIS SHOULD CONTINUE TO BE THE CASE THROUGH THE
WEEKEND.
CONDITIONS SHOULD REMAIN BELOW SCA CRITERIA THROUGH THE DAY
SATURDAY. SOUTHERLY WINDS MAY GAIN ENOUGH SOUTHERLY FETCH TO PRODUCE
MARGINAL 5 FOOT SEAS OVER THE NORTHERN COASTAL WATERS BY SATURDAY
NIGHT. HOWEVER...THE MAIN SCA EVENT SHOULD BEGIN SUNDAY NIGHT OVER
THE COASTAL WATERS NORTH OF CAPE CHARLES. ELSEWHERE...CONDITIONS
SHOULD BE JUST SHORT OF SCA AS A COLD FRONT APPROACHES THE REGION.
THE FRONT MOVES SLOWLY TO THE EAST MONDAY NIGHT AND TUESDAY. PRESENT
INDICATIONS ARE THAT THE POST FRONTAL ENVIRONMENT WILL FAIL TO
PRODUCE SCA BUT THIS MAY CHANGE.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...AIR QUALITY ALERT UNTIL MIDNIGHT EDT TONIGHT FOR MDZ021>024.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MAM
NEAR TERM...MAM
SHORT TERM...MPR/MAM
LONG TERM...MAS
AVIATION...LSA
MARINE...LSA
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
702 AM EDT FRI MAY 31 2013
.SYNOPSIS...
HIGH PRESSURE REMAINS ANCHORED OFF THE MID ATLANTIC COAST THROUGH
SUNDAY. A COLD FRONT WILL BRING INCREASING RAIN CHANCES...AS IT
SLOWLY CROSSES THE AREA ON MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
VERY SIMILAR DAY WXWISE TO THU ON THE WAY FOR TODAY. EXPECTING
ANOTHER VERY WARM DAY, AS THE SFC RIDGE AND STRENGTHENING H5 RIDGE
ALOFT REMAINS QUASI- STATIONARY WELL OFFSHORE.
DRY WEATHER CONTINUES TODAY WITH PERSISTENT WARM/STABLE AIR ALOFT
AND A LACK OF AVAILABLE TRIGGERS FOR LIFT. HIGH-RES MODELS
(SPECIFICALLY THE HRRR AND SPC WRF) AGAIN PICKING UP THE THE
POTENTIAL FOR AN ISOLATED SHOWER OR TWO BLOWING UP ON AFTN
SEABREEZE OVER THE FAR SOUTHEAST PART OF THE CWA (AND ALSO ALONG
THE MASON-DIXON IN ASSN WITH A WEAK, SHEARED OUT SHORTWAVE
CROSSING WELL NORTH OF THE AKQ CWA). AS WITH YESTERDAY THOUGH,
RAIN CHC ACROSS LOCAL AREA REMAINS TOO SMALL TO INCLUDE POPS IN
THE FORECAST. THUS, HV CONTINUED TO CAP RAIN CHANCES AT 10% OR
LESS. HIGH TEMPERATURES AWAY FROM THE IMMEDIATE COAST AGAIN
GENERALLY ~90/L90S INLAND, LOW TO MID 80S AT IMMEDIATE COASTAL
AREAS.
CLEAR AND MILD OVERNIGHT...EARLY MORNING LOWS SAT MORNING IN THE
U60S TO NR 70.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
GRADUALLY WEAKENING H5 RIDGE OFF THE MID ATLANTIC COAST SHIFTS
SLIGHTLY TO THE EAST SATURDAY AND SUNDAY AHEAD OF APPROACHING
MID-LVL TROUGH, WHICH PUSHES FROM THE NORTHERN PLAINS TOWARDS THE
UPR GRT LAKES ON SUNDAY. HOWEVER, SFC/UPR LEVEL RIDGING OFFSHORE
WL REMAIN THE DOMINATE WX FEATURE THRU THE WEEKEND, BRINGING
CONTINUED SUMMER-LIKE CONDITIONS. LTL (IF ANY) TRIGGER EXISTS FOR
CONVECTION ON SAT, AS AIRMASS REMAINS LARGELY CAPPED. FCST
REMAINS DRY AS BEST CHCS FOR ANY CONVECTION WILL AGAIN BE CONFINED
OVER THE MTNS. HIGHS SAT IN THE U80S-L90S, THOUGH AGAIN COOLER AT
THE BEACHES DUE TO LCL AFTN SEA BREEZE EFFECTS.
PARTLY TO MOSTLY CLEAR SKY FOR MOST OF SAT NIGHT, THOUGH WL NEED
TO WATCH GFS, AS IT CONTINUES TO KEY IN ON POTENTIAL FOR SOME LOW
STRATUS OVER THE I-85 CORRIDOR BACK INTO THE CENTRAL NC PIEDMONT
LATE. ERY MORNING LOWS SUNDAY MORNING IN THE M-U60S.
AFTER ANY LINGERING STRATUS QUICKLY LIFTS/ERODES SUNDAY MORNING,
THE DAY STARTS OUT MAINLY SUNNY. HOWEVER, CLOUDS LOOK TO INCREASE
FROM THE WEST BY SUN AFTN AHEAD OF APPROACHING FRONTAL BOUNDARY.
SLIGHT CHC TO LOW CHC POPS STILL LOOK GOOD BY MID AFTN SUNDAY AS
TSRAS LOOK TO FIRE ALONG PRE-FRONTAL/LEE TROUGHING TO THE WEST AND
PUSH E-NE ACROSS OUR WESTERN TIER OF COUNTIES (WEST OF RIC) LATE
SUN AFTN. MORE IN THE WAY OF CLOUD COVER WILL BE BALANCED OUT BY
STRONG COMPRESSIONAL HEATING AHEAD OF THE FRONT, AGAIN YIELDING
HIGHS IN THE U80S TO NR 90. GIVEN DP TEMPS IN THE L-M60S (HIGHEST
JUST BEFORE DIURNAL MIXING KICKS IN JUST AFTER 12Z)...HEAT INDEX
VALUES XPCTD TO REMAIN WITHIN A DEGREE OR TWO OF ACTUAL TEMPS BOTH
DAYS.
ECMWF/GFS IN PRETTY GOOD AGREEMENT REGARDING FROPA/PCPN TIMING FOR
SUNDAY NIGHT AND MONDAY. FRONT SLOWLY APPROACHES, AND BEGINS TO
PUSH ACROSS THE WESTERN THIRD OF THE LOCAL AREA LATE SUNDAY
NIGHT/MONDAY MORNING. DUE TO THE LATE NIGHT/ERY MORNING TIMING,
INSTABILITY ATTM LOOKS TO BE MARGINAL AT BEST, SO WILL GO WITH ISO
T WORDING FOR NOW. STILL, AS PW VALUES SHOOT UPWARDS OF 1.75"
AREA-WIDE SUNDAY NIGHT, RAIN CHANCES ARE LOOKING INCREASINGLY
FAVORABLE ACROSS THE PIEDMONT AFTER 00Z MON/8PM SUNDAY NIGHT.
THUS, WL GO WITH LKLY POP WEST OF I-95 LT SUNDAY NIGHT, WITH CHCS
INCREASING FARTHER EAST AFTER MIDNIGHT THRU DAWN MONDAY MORNING.
GIVEN THE CONSIDERABLE CLDS/PCPN, WL GO CLOSER TO EURO STATISTICAL
GUIDANCE, WHICH IS ABT A CATEGORY ABOVE 00Z/31 MEX NUMBERS. ERY
MORNING LOWS MON MORNING RIGHT AROUND 70/LOW 70S.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
LONG TERM PERIOD BEGINS W/ THE FRONT SLOWLY MOVING ACRS THE AREA
MON, WITH SHRAS/TSTMS EXPECTED ACROSS THE AREA. ALTHO WAA IS
WEAK...DEEP LAYER MOISTURE...MID-LVL S/W ENERGY AND UPR-LVL
DIVERGENCE CONTINUE TO WARRANT LIKELY POPS...CONTINUING INTO SE
AREAS MON NGT. GIVEN THE RAIN AND CLDS...TEMPS MON WILL MAX OUT IN
THE UPR 70S TO MID 80S. THE RAIN WILL END FROM W TO E EARLY TUE AS
THE FRONT SLIDES OFFSHORE. SFC HI PRES THEN BLDS IN FROM THE
NW...WITH HIGHS ONLY IN THE UPR 70S TO LO 80S ON TUE AND WED.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
MAINLY S-SW WINDS ARE EXPECTED TO CONTINUE FOR THE 12Z TAF PERIOD
WITH ONE POSSIBLE EXCEPTION. WINDS AT ORF MAY BE INFLUENCED ONCE
AGAIN BY A BAY BREEZE AS SYNOPTIC WINDS WILL BE A BIT LIGHTER THAN
ON THURSDAY. MODELS ARE NOT CLEAR ON THE DIRECTION AND WENT VRBL
AND LIGHT. NO SUBSTANTIAL CLOUDINESS IS INDICATED SO KEPT SKC
THROUGH THE PERIOD.
SOME LOCATIONS OTHER THAN THE TAF SITES REPORTED PATCHY FOG. WITH
THE COLUMN SLOWLY MOISTENING WITH TIME...FOG MAY BE REPORTED AT
SOME OF THE TAF SITES WHERE WINDS DIMINISH SUFFICIENTLY. INCLUDED
4 MILES AT RIC FOR NOW AFT 09Z. WINDS MAY BE TOO STRONG AT THE
OTHER FOUR SITES BUT THIS WILL NEED TO MONITORED. CONFIDENCE IS
LOW FOR THE MVFR STRATUS THAT MAV MOS HAS FOR ECG.
OUTLOOK...THERE WILL BE A BETTER CHANCE FOR MVFR/IFR FOG OR
STRATUS SUNDAY MORNING. ISOLATED THUNDERSTORMS WILL BE PSBL
SUNDAY EVENING. THE CHANCES INCREASE MONDAY AHEAD OF AN
APPROACHING COLD FRONT. DRY/VFR CONDITIONS RETURN BY TUESDAY.
&&
.MARINE...
WINDS WILL CONTINUE TO BE GENERALLY FROM THE SOUTH THROUGH THE
WEEKEND. WIND SPEEDS AT ELEVATED SITES ARE RUNNING SEVERAL KNOTS
HIGHER THAN THOSE NEAR THE SURFACE OF THE WATER DUE TO POOR MIXING
WITH THE COLD WATER. THIS SHOULD CONTINUE TO BE THE CASE THROUGH THE
WEEKEND.
CONDITIONS SHOULD REMAIN BELOW SCA CRITERIA THROUGH THE DAY
SATURDAY. SOUTHERLY WINDS MAY GAIN ENOUGH SOUTHERLY FETCH TO PRODUCE
MARGINAL 5 FOOT SEAS OVER THE NORTHERN COASTAL WATERS BY SATURDAY
NIGHT. HOWEVER...THE MAIN SCA EVENT SHOULD BEGIN SUNDAY NIGHT OVER
THE COASTAL WATERS NORTH OF CAPE CHARLES. ELSEWHERE...CONDITIONS
SHOULD BE JUST SHORT OF SCA AS A COLD FRONT APPROACHES THE REGION.
THE FRONT MOVES SLOWLY TO THE EAST MONDAY NIGHT AND TUESDAY. PRESENT
INDICATIONS ARE THAT THE POST FRONTAL ENVIRONMENT WILL FAIL TO
PRODUCE SCA BUT THIS MAY CHANGE.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...AIR QUALITY ALERT UNTIL MIDNIGHT EDT TONIGHT FOR MDZ021>024.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MAM
NEAR TERM...MAM
SHORT TERM...MPR/MAM
LONG TERM...MAS
AVIATION...LSA
MARINE...LSA
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
446 AM EDT FRI MAY 31 2013
.SYNOPSIS...
HIGH PRESSURE REMAINS ANCHORED OFF THE MID ATLANTIC COAST THROUGH
SUNDAY. A COLD FRONT WILL BRING INCREASING RAIN CHANCES...AS IT
SLOWLY CROSSES THE AREA ON MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
VERY SIMILAR DAY WXWISE TO THU ON THE WAY FOR TODAY. EXPECTING
ANOTHER VERY WARM DAY, AS THE SFC RIDGE AND STRENGTHENING H5 RIDGE
ALOFT REMAINS QUASI- STATIONARY WELL OFFSHORE.
DRY WEATHER CONTINUES TODAY WITH PERSISTENT WARM/STABLE AIR ALOFT
AND A LACK OF AVAILABLE TRIGGERS FOR LIFT. HIGH-RES MODELS
(SPECIFICALLY THE HRRR AND SPC WRF) AGAIN PICKING UP THE THE
POTENTIAL FOR AN ISOLATED SHOWER OR TWO BLOWING UP ON AFTN
SEABREEZE OVER THE FAR SOUTHEAST PART OF THE CWA (AND ALSO ALONG
THE MASON-DIXON IN ASSN WITH A WEAK, SHEARED OUT SHORTWAVE
CROSSING WELL NORTH OF THE AKQ CWA). AS WITH YESTERDAY THOUGH,
RAIN CHC ACROSS LOCAL AREA REMAINS TOO SMALL TO INCLUDE POPS IN
THE FORECAST. THUS, HV CONTINUED TO CAP RAIN CHANCES AT 10% OR
LESS. HIGH TEMPERATURES AWAY FROM THE IMMEDIATE COAST AGAIN
GENERALLY ~90/L90S INLAND, LOW TO MID 80S AT IMMEDIATE COASTAL
AREAS.
CLEAR AND MILD OVERNIGHT...EARLY MORNING LOWS SAT MORNING IN THE
U60S TO NR 70.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
GRADUALLY WEAKENING H5 RIDGE OFF THE MID ATLANTIC COAST SHIFTS
SLIGHTLY TO THE EAST SATURDAY AND SUNDAY AHEAD OF APPROACHING
MID-LVL TROUGH, WHICH PUSHES FROM THE NORTHERN PLAINS TOWARDS THE
UPR GRT LAKES ON SUNDAY. HOWEVER, SFC/UPR LEVEL RIDGING OFFSHORE
WL REMAIN THE DOMINATE WX FEATURE THRU THE WEEKEND, BRINGING
CONTINUED SUMMER-LIKE CONDITIONS. LTL (IF ANY) TRIGGER EXISTS FOR
CONVECTION ON SAT, AS AIRMASS REMAINS LARGELY CAPPED. FCST
REMAINS DRY AS BEST CHCS FOR ANY CONVECTION WILL AGAIN BE CONFINED
OVER THE MTNS. HIGHS SAT IN THE U80S-L90S, THOUGH AGAIN COOLER AT
THE BEACHES DUE TO LCL AFTN SEA BREEZE EFFECTS.
PARTLY TO MOSTLY CLEAR SKY FOR MOST OF SAT NIGHT, THOUGH WL NEED
TO WATCH GFS, AS IT CONTINUES TO KEY IN ON POTENTIAL FOR SOME LOW
STRATUS OVER THE I-85 CORRIDOR BACK INTO THE CENTRAL NC PIEDMONT
LATE. ERY MORNING LOWS SUNDAY MORNING IN THE M-U60S.
AFTER ANY LINGERING STRATUS QUICKLY LIFTS/ERODES SUNDAY MORNING,
THE DAY STARTS OUT MAINLY SUNNY. HOWEVER, CLOUDS LOOK TO INCREASE
FROM THE WEST BY SUN AFTN AHEAD OF APPROACHING FRONTAL BOUNDARY.
SLIGHT CHC TO LOW CHC POPS STILL LOOK GOOD BY MID AFTN SUNDAY AS
TSRAS LOOK TO FIRE ALONG PRE-FRONTAL/LEE TROUGHING TO THE WEST AND
PUSH E-NE ACROSS OUR WESTERN TIER OF COUNTIES (WEST OF RIC) LATE
SUN AFTN. MORE IN THE WAY OF CLOUD COVER WILL BE BALANCED OUT BY
STRONG COMPRESSIONAL HEATING AHEAD OF THE FRONT, AGAIN YIELDING
HIGHS IN THE U80S TO NR 90. GIVEN DP TEMPS IN THE L-M60S (HIGHEST
JUST BEFORE DIURNAL MIXING KICKS IN JUST AFTER 12Z)...HEAT INDEX
VALUES XPCTD TO REMAIN WITHIN A DEGREE OR TWO OF ACTUAL TEMPS BOTH
DAYS.
ECMWF/GFS IN PRETTY GOOD AGREEMENT REGARDING FROPA/PCPN TIMING FOR
SUNDAY NIGHT AND MONDAY. FRONT SLOWLY APPROACHES, AND BEGINS TO
PUSH ACROSS THE WESTERN THIRD OF THE LOCAL AREA LATE SUNDAY
NIGHT/MONDAY MORNING. DUE TO THE LATE NIGHT/ERY MORNING TIMING,
INSTABILITY ATTM LOOKS TO BE MARGINAL AT BEST, SO WILL GO WITH ISO
T WORDING FOR NOW. STILL, AS PW VALUES SHOOT UPWARDS OF 1.75"
AREA-WIDE SUNDAY NIGHT, RAIN CHANCES ARE LOOKING INCREASINGLY
FAVORABLE ACROSS THE PIEDMONT AFTER 00Z MON/8PM SUNDAY NIGHT.
THUS, WL GO WITH LKLY POP WEST OF I-95 LT SUNDAY NIGHT, WITH CHCS
INCREASING FARTHER EAST AFTER MIDNIGHT THRU DAWN MONDAY MORNING.
GIVEN THE CONSIDERABLE CLDS/PCPN, WL GO CLOSER TO EURO STATISTICAL
GUIDANCE, WHICH IS ABT A CATEGORY ABOVE 00Z/31 MEX NUMBERS. ERY
MORNING LOWS MON MORNING RIGHT AROUND 70/LOW 70S.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
LONG TERM PERIOD BEGINS W/ THE FRONT SLOWLY MOVING ACRS THE AREA
MON, WITH SHRAS/TSTMS EXPECTED ACROSS THE AREA. ALTHO WAA IS
WEAK...DEEP LAYER MOISTURE...MID-LVL S/W ENERGY AND UPR-LVL
DIVERGENCE CONTINUE TO WARRANT LIKELY POPS...CONTINUING INTO SE
AREAS MON NGT. GIVEN THE RAIN AND CLDS...TEMPS MON WILL MAX OUT IN
THE UPR 70S TO MID 80S. THE RAIN WILL END FROM W TO E EARLY TUE AS
THE FRONT SLIDES OFFSHORE. SFC HI PRES THEN BLDS IN FROM THE
NW...WITH HIGHS ONLY IN THE UPR 70S TO LO 80S ON TUE AND WED.
&&
.AVIATION /09Z FRIDAY THROUGH TUESDAY/...
MAINLY S-SW WINDS ARE EXPECTED TO CONTINUE FOR THE 06Z TAF PERIOD
WITH ONE POSSIBLE EXCEPTION. WINDS AT ORF MAY BE INFLUENCED ONCE
AGAIN BY A BAY BREEZE AS SYNOPTIC WINDS WILL BE A BIT LIGHTER THAN
ON THURSDAY. MODELS ARE NOT CLEAR ON THE DIRECTION AND WENT VRBL AND
LIGHT. NO SUBSTANTIAL CLOUDINESS IS INDICATED SO KEPT SKC THROUGH
THE PERIOD.
THE TEMPERATURE DEW POINT SPREAD MAY LOWER TO 3 DEGREES OR LESS AT A
COUPLE OF THE TAF SITES. THE COMBINATION OF A STEADY S/SW WIND AND
DRY CONDITIONS AT THE SURFACE SHOULD PRECLUDE FOG FRIDAY MORNING.
OUTLOOK...HIGH PRESSURE REMAINS THE DOMINANT WX FEATURE ACROSS
THE REGION WITH DRY/VFR WX CONTINUING THROUGH SATURDAY. ISOLATED
THUNDERSTORMS WILL BE PSBL SUNDAY EVENING. THE CHANCES INCREASE
MONDAY AHEAD OF AN APPROACHING COLD FRONT.
&&
.MARINE...
WINDS WILL CONTINUE TO BE GENERALLY FROM THE SOUTH THROUGH THE
WEEKEND. WIND SPEEDS AT ELEVATED SITES ARE RUNNING SEVERAL KNOTS
HIGHER THAN THOSE NEAR THE SURFACE OF THE WATER DUE TO POOR MIXING
WITH THE COLD WATER. THIS SHOULD CONTINUE TO BE THE CASE THROUGH THE
WEEKEND.
CONDITIONS SHOULD REMAIN BELOW SCA CRITERIA THROUGH THE DAY
SATURDAY. SOUTHERLY WINDS MAY GAIN ENOUGH SOUTHERLY FETCH TO PRODUCE
MARGINAL 5 FOOT SEAS OVER THE NORTHERN COASTAL WATERS BY SATURDAY
NIGHT. HOWEVER...THE MAIN SCA EVENT SHOULD BEGIN SUNDAY NIGHT OVER
THE COASTAL WATERS NORTH OF CAPE CHARLES. ELSEWHERE...CONDITIONS
SHOULD BE JUST SHORT OF SCA AS A COLD FRONT APPROACHES THE REGION.
THE FRONT MOVES SLOWLY TO THE EAST MONDAY NIGHT AND TUESDAY. PRESENT
INDICATIONS ARE THAT THE POST FRONTAL ENVIRONMENT WILL FAIL TO
PRODUCE SCA BUT THIS MAY CHANGE.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...AIR QUALITY ALERT UNTIL MIDNIGHT EDT TONIGHT FOR MDZ021>024.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MAM
NEAR TERM...MAM
SHORT TERM...MPR/MAM
LONG TERM...MAS
AVIATION...LSA
MARINE...LSA
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
349 AM EDT FRI MAY 31 2013
.SYNOPSIS...
HIGH PRESSURE REMAINS ANCHORED OFF THE MID ATLANTIC COAST THROUGH
SUNDAY. A COLD FRONT WILL BRING INCREASING RAIN CHANCES...AS IT
SLOWLY CROSSES THE AREA ON MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
VERY SIMILAR DAY WXWISE ON THE WAY TODAY. CONTINUED VERY WARM AS
THE SFC RIDGE AND STRENGTHENING H5 RIDGE ALOFT REMAINS QUASI-
STATIONARY WELL OFFSHORE.
DRY WEATHER CONTINUES TODAY WITH PERSISTENT WARM/STABLE AIR ALOFT
AND A LACK OF AVAILABLE TRIGGERS FOR LIFT. HIGH-RES MODELS
(SPECIFICALLY THE HRRR AND SPC WRF) AGAIN PICKING UP THE THE
POTENTIAL FOR AN ISOLATED SHOWER OR TWO BLOWING UP ON AFTN
SEABREEZE OVER THE FAR SOUTHEAST PART OF THE CWA (AND ALSO ALONG
THE MASON-DIXON IN ASSN WITH A WEAK, SHEARED OUT SHORTWAVE
CROSSING WELL NORTH OF THE AKQ CWA). AS WITH YESTERDAY THOUGH,
RAIN CHC ACROSS LOCAL AREA REMAINS TOO SMALL TO INCLUDE POPS IN
THE FORECAST. THUS, HV CONTINUED TO CAP RAIN CHANCES AT 10% OR
LESS. HIGH TEMPERATURES AWAY FROM THE IMMEDIATE COAST AGAIN
GENERALLY ~90/L90S INLAND, LOW TO MID 80S AT IMMEDIATE COASTAL
AREAS.
CLEAR AND MILD OVERNIGHT...EARLY MORNING LOWS SAT MORNING IN THE
U60S TO NR 70.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
GRADUALLY WEAKENING H5 RIDGE OFF THE MID ATLANTIC COAST SHIFTS
SLIGHTLY TO THE EAST SATURDAY AND SUNDAY AHEAD OF APPROACHING
MID-LVL TROUGH, WHICH PUSHES FROM THE NORTHERN PLAINS TOWARDS THE
UPR GRT LAKES ON SUNDAY. HOWEVER, SFC/UPR LEVEL RIDGING OFFSHORE
WL REMAIN THE DOMINATE WX FEATURE THRU THE WEEKEND, BRINGING
CONTINUED SUMMER-LIKE CONDITIONS. LTL (IF ANY) TRIGGER EXISTS FOR
CONVECTION ON SAT, AS AIRMASS REMAINS LARGELY CAPPED. FCST
REMAINS DRY AS BEST CHCS FOR ANY CONVECTION WILL AGAIN BE CONFINED
OVER THE MTNS. HIGHS SAT IN THE U80S-L90S...AGAIN COOLER AT THE
BEACHES DUE TO LCL AFTN SEA BREEZE EFFECTS.
PARTLY TO MOSTLY CLEAR SKY FOR MOST OF SAT NIGHT, THOUGH GFS
CONTINUES TO KEY IN ON POTENTIAL FOR SOME LOW STRATUS OVER THE
I-85 CORRIDOR BACK INTO THE CENTRAL NC PIEDMONT LATE. ERY MORNING
LOWS IN THE M-U60S.
AFTER ANY LINGERING STRATUS QUICKLY LIFTS/ERODES SUNDAY MORNING,
THE DAY STARTS OUT MAINLY SUNNY. HOWEVER, CLOUDS LOOK TO INCREASE
FROM THE WEST SUN AFTN AHEAD OF APPROACHING FRONTAL BOUNDARY.
SLIGHT CHC TO LOW CHC POPS STILL LOOK GOOD BY MID AFTN SUNDAY AS
TSRAS LOOK TO FIRE ALONG PRE-FRONTAL/LEE TROUGHING TO THE WEST
AND PUSH E-NE ACROSS OUR WESTERN TIER OF COUNTIES LATE SUN AFTN.
MORE CLOUD COVER BALANCED OUT BY STRONG COMPRESSIONAL HEATING
AHEAD OF THE FRONT WILL AGAIN YIELD HIGHS IN THE U80S TO NR 90.
GIVEN DP TEMPS IN THE L-M60S (HIGHEST JUST BEFORE DIURNAL MIXING
KICKS IN JUST AFTER 12Z)...HEAT INDEX VALUES XPCTD TO REMAIN
WITHIN A DEGREE OR TWO OF ACTUAL TEMPS BOTH DAYS.
ECMWF/GFS IN PRETTY GOOD AGREEMENT REGARDING FROPA/PCPN TIMING FOR
SUNDAY NIGHT AND MONDAY. FRONT SLOWLY APPROACHES, AND BEGINS TO
PUSH ACROSS THE LOCAL AREA LATE SUNDAY NIGHT/MONDAY MORNING. DUE
TO THE LATE NIGHT/ERY MORNING TIMING, INSTABILITY ATTM LOOKS TO BE
MARGINAL AT BEST, SO WILL GO WITH ISO T WORDING FOR NOW. STILL,
AS PW VALUES SHOOT UPWARDS OF 1.75" AREA-WIDE SUNDAY NIGHT, RAIN
CHANCES ARE LOOKING INCREASINGLY FAVORABLE ACROSS THE PIEDMONT
AFTER 00Z MON/8PM SUNDAY NIGHT. THUS, WL GO WITH LKLY POP WEST OF
I-95 LT SUNDAY NIGHT, WITH CHCS INCREASING FARTHER EAST AFTER
MIDNIGHT THRU DAWN MONDAY MORNING. GIVEN THE CONSIDERABLE CLDS/PCPN,
WL GO CLOSER TO EURO STATISTICAL GUIDANCE, WHICH IS ABT A CATEGORY
ABOVE 00Z/31 MEX NUMBERS. ERY MORNING LOWS MON MORNING RIGHT
AROUND 70/LOW 70S.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
LONG TERM PERIOD STARTS OUT W/ THE FRONT SLOWLY MOVING ACRS THE
AREA MON, WITH SHRAS/TSTMS ACROSS THE AREA. ALTHO WAA IS
WEAK...DEEP LAYER MOISTURE...MID-LVL S/W ENERGY AND UPR-LVL
DIVERGENCE CONTINUE TO WARRANT LIKELY POPS...CONTINUING INTO SE
AREAS MON NGT. GIVEN THE RAIN AND CLDS...TEMPS MON WILL MAX OUT
IN THE UPR 70S TO MID 80S. THE RAIN WILL END FROM W TO E EARLY TUE
AS THE FRONT SLIDES OFFSHORE. SFC HI PRES THEN BLDS IN FROM THE
NW...WITH HIGHS ONLY IN THE UPR 70S TO LO 80S ON TUE AND WED.
&&
.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
MAINLY S-SW WINDS ARE EXPECTED TO CONTINUE FOR THE 06Z TAF PERIOD
WITH ONE POSSIBLE EXCEPTION. WINDS AT ORF MAY BE INFLUENCED ONCE
AGAIN BY A BAY BREEZE AS SYNOPTIC WINDS WILL BE A BIT LIGHTER THAN
ON THURSDAY. MODELS ARE NOT CLEAR ON THE DIRECTION AND WENT VRBL AND
LIGHT. NO SUBSTANTIAL CLOUDINESS IS INDICATED SO KEPT SKC THROUGH
THE PERIOD.
THE TEMPERATURE DEW POINT SPREAD MAY LOWER TO 3 DEGREES OR LESS AT A
COUPLE OF THE TAF SITES. THE COMBINATION OF A STEADY S/SW WIND AND
DRY CONDITIONS AT THE SURFACE SHOULD PRECLUDE FOG FRIDAY MORNING.
OUTLOOK...HIGH PRESSURE REMAINS THE DOMINANT WX FEATURE ACROSS
THE REGION WITH DRY/VFR WX CONTINUING THROUGH SATURDAY. ISOLATED
THUNDERSTORMS WILL BE PSBL SUNDAY EVENING. THE CHANCES INCREASE
MONDAY AHEAD OF AN APPROACHING COLD FRONT.
&&
.MARINE...
WINDS WILL CONTINUE TO BE GENERALLY FROM THE SOUTH THROUGH THE
WEEKEND. WIND SPEEDS AT ELEVATED SITES ARE RUNNING SEVERAL KNOTS
HIGHER THAN THOSE NEAR THE SURFACE OF THE WATER DUE TO POOR MIXING
WITH THE COLD WATER. THIS SHOULD CONTINUE TO BE THE CASE THROUGH THE
WEEKEND.
CONDITIONS SHOULD REMAIN BELOW SCA CRITERIA THROUGH THE DAY
SATURDAY. SOUTHERLY WINDS MAY GAIN ENOUGH SOUTHERLY FETCH TO PRODUCE
MARGINAL 5 FOOT SEAS OVER THE NORTHERN COASTAL WATERS BY SATURDAY
NIGHT. HOWEVER...THE MAIN SCA EVENT SHOULD BEGIN SUNDAY NIGHT OVER
THE COASTAL WATERS NORTH OF CAPE CHARLES. ELSEWHERE...CONDITIONS
SHOULD BE JUST SHORT OF SCA AS A COLD FRONT APPROACHES THE REGION.
THE FRONT MOVES SLOWLY TO THE EAST MONDAY NIGHT AND TUESDAY. PRESENT
INDICATIONS ARE THAT THE POST FRONTAL ENVIRONMENT WILL FAIL TO
PRODUCE SCA BUT THIS MAY CHANGE.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...AIR QUALITY ALERT UNTIL MIDNIGHT EDT TONIGHT FOR MDZ021>024.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MAM
NEAR TERM...MAM
SHORT TERM...MPR/MAM
LONG TERM...MAS
AVIATION...LSA
MARINE...LSA
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1221 PM CDT FRI MAY 31 2013
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 330 AM CDT FRI MAY 31 2013
EARLY MORNING WATER VAPOR IMAGERY TOGETHER WITH THE PRESSURE OF THE
1.5PVU SURFACE SHOWED A NARROW RIBBON OF POTENTIAL VORTICITY
PROTRUDING DOWN TO THE 450/500MB LEVEL. THIS PV RESERVOIR
ORIGINATED UPSTREAM OFF THE BRITISH COLUMBIA COAST...EXTENDED
SOUTHEAST ACROSS THE KS/NE BORDER...AND CURLED UP OVER THE UPPER
MIDWEST. OVERLAYING THE 300MB WINDS SHOWED AN AREA OF POSITIVE
VORTICITY OWING TO THE EASTERLY WINDS OF 30KTS ON THE POLEWARD SIDE
OF +100KT WESTERLY JET. AT THE SURFACE A 991 LOW WAS LOCATED BENEATH
THE LEADING EDGE OF THE PV GRADIENT ALONG THE SD/ND BORDER...WITH A
SURFACE COLD FRONT DRAPED ON THE EASTERN SIDE OF THE MISSOURI
RIVER VALLEY.
FOR TODAY THE 00Z RUN OF THE HOPWRF AND FEW RUNS OF
THE HRRR SHOWS ANOTHER ACTIVE DAY SOUTH AND EAST OF THE CWA WITH
SEVERAL THUNDERSTORM COMPLEXES EXPECTED TO DEVELOP AS THE DEEP SHEAR
ASSOCIATED WITH THE AFOREMENTIONED UPPER LEVEL JET MOVE ACROSS THE
MISSISSIPPI RIVER VALLEY. MEANWHILE IT SHOULD BE MAINLY DRY FOR THE
FIRST HALF OF FRIDAY ACROSS THE CWA. IN FACT FORECAST SOUNDINGS VIA
THE RAP SUPPORT MOSTLY SUNNY SKIES DURING THE MORNING HOURS.
HOWEVER...WITH THE VORT MAX ROTATING OVERHEAD EXPECT INCREASING
CLOUDS WITH SHOWERS/THUNDERSTORMS AS THE ATMOSPHERE DESTABILIZES BY
MID AFTERNOON...MORE SO THAN THE HIRES MODELS WOULD INDICATE. THE
BEST DEEP LAYER SHEAR WILL BE ACROSS EASTERN IOWA AND WISCONSIN...SO
SEVERE THREAT IS LOW IN MINNESOTA...BUT COULD SEE SOME STRONGER
STORMS IN WEST CENTRAL WISCONSIN. BUFR FORECAST SOUNDINGS SHOW
ROUGHLY 1000J/KG OF MLCAPE AND FREEZING LEVELS AROUND 9-10KFT
AGL...SO WOULD NOT BE SURPRISED TO GET SOME SMALL HAIL AND GUSTY
WINDS WITH A FEW OF THE STRONGER CELLS. THE BEST CHANCE FOR DEEPER
CONVECTION WILL BE IN EASTERN MN AND WESTERN WI. ON FRIDAY NIGHT
THE INSTABILITY WILL DECREASE GIVING WAY TO LIGHT WINDS AND LOW
STRATUS AS THE OCCLUDED CYCLONE SLOWLY WOBBLES EASTWARD. A FEW
LIGHT RAIN SHOWERS DEVELOP ACROSS THE WESTERN HALF OF THE CWA AS
INDICATED BY THE LOW LEVEL SATURATION SHOWN IN THE BUFR SOUNDINGS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 330 AM CDT FRI MAY 31 2013
CLOSED UPPER CIRCULATION OVER THE REGION SATURDAY. IT SHOULD
PROVIDE GENERAL CLOUDINESS AND THE THREAT OF SHOWERS MUCH OF THE
DAY. AS THE CIRCULATION PIVOTS EAST NORTHEAST AND WEAKENS...MODELS
SUGGEST SOME WEAK SURFACE BASED CAPE AND SOME SLIGHTLY NEGATIVE
BEST LI`S OVER EASTERN AREAS...INTO THE AFTERNOON. WILL NEED SOME
BREAKS IN THE CLOUDS TO GENERATE ANY SIGNIFICANT DESTABILIZATION.
OPTED TO MENTION ISOLATED THUNDER OVER THE EAST PORTION OF THE
CWA...MAINLY IN THE AFTERNOON. WITH SIGNIFICANT CLOUD COVER
AROUND...TEMPERATURES MAY NOT GET OUT OF THE 50S OVER THE WEST AND
WILL REMAIN IN THE 60S EAST.
THIS INITIAL SYSTEM MOVES EAST...AND BECOMES MORE PROGRESSIVE AS
THE NEXT SIGNIFICANT TROUGH MOVES ASHORE OVER THE PACIFIC
NORTHWEST LATER SUNDAY. THIS SHOULD PROVIDE A CLEARING
TREND...ALONG WITH DRIER CONDITIONS SUNDAY INTO MONDAY. SOME
RETURN FLOW...WARM AIR ADVECTION PATTERN DEVELOPS DURING THE DAY
MONDAY...MAINLY OVER THE FAR WEST. THE WESTERN CLOSED CIRCULATION
MOVES SLOWLY EAST OVER THE REGION...AND APPEARS TO AFFECT THE AREA
FOR THE REMAINDER OF THE WEEK. THIS WILL AGAIN PROVIDE A LONG
PERIOD OF CLOUDINESS AND THE THREAT OF SHOWERS AND THUNDERSTORMS
TO THE CWA. TUESDAY AND WEDNESDAY LOOK TO BE THE WETTEST DAYS...BUT
THE SHOWERY WEATHER PATTERN WILL CONTINUE THROUGH THURSDAY. THE
BELOW NORMAL TEMPERATURE PATTERN WILL ALSO CONTINUE INTO THE
FIRST PART OF JUNE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1205 PM CDT FRI MAY 31 2013
SHRA HAVE ALREADY DEVELOPED IN SE MN AHEAD OF A STRONG SHRTWV
ACROSS WESTERN IOWA. BEST INSTABILITY AND SHEAR WILL REMAIN EAST
OF THE FA...BUT RNH/MSP/EAU DO HAVE THE POTENTIAL OF GETTING
STRONGER STORMS AS EARLY AS 1-2 PM. EAU HAS THE BEST POTENTIAL OF
SVR WIND GUSTS AND LARGE HAIL BEFORE 1Z/01. ACROSS WESTERN MN...THE
UPPER LOW HAS NEARLY STALLED. BUT THIS LOW IS EXPECT TO SLOWLY
FILL AND MOVE TO THE E-NE OVER THE NEXT DAY OR SO. IFR/MVFR CIGS
WITH SCATTERED SHRA WILL OCCUR NEAR AND UNDER THIS LOW PRESSURE
SYSTEM...WITH THE BEST POTENTIAL OF -SHRA OCCURRING DURING THE
TYPICAL MID AFTN...TO LATE EVENING HRS AS INSTABILITY WILL BE THE
GREATEST. MVFR CIGS THIS AFTN WILL LIKELY RISE TO LOW END VFR IN
WESTERN MN...BUT LOWER ONCE AGAIN DURING THE EVENING AS THE LOW
TRACKS E-NE ACROSS THE NORTHERN FA. TIMING OF THE INITIAL TSRA
DEVELOPMENT ACROSS FAR EASTERN MN/WC WI WILL BE DEPENDENT ON WHEN
THE WEAKENING CAP BREAKS. AS PREVIOUSLY STATED...TSRA COULD
DEVELOP AS EARLY AS 1-2 PM BASED ON THE LATEST MESOSCALE MODEL
RUNS. SFC WINDS WILL BE STRONGEST THRU 21Z...THEN DECREASE AND
BECOMING LIGHT AND VARIABLE OVERNIGHT. ONCE THE LOW MOVES TO THE
EAST...WINDS WILL SHIFT TO THE SW/W...AND EVENTUALLY NW AND
INCREASE IN SPD.
KMSP...
BEST TIME FRAME FOR TSRA/SHRA WILL OCCUR BETWEEN 19-22Z...WITH
ONLY SHRA AFT 22Z. ANY TSRA THAT DUE DEVELOP HAVE THE CAPABILITY
OF PRODUCING VERY GUSTY WINDS UP TO 40 KTS...AND SMALL HAIL. WILL
MONITOR THE POTENTIAL OF AN AWW IF NEEDED. THIS EVENING WILL BE
VFR WITH WINDS DECREASE AND SHIFTING TO THE SW UNDER 6 KTS. BY
12-15Z...WINDS WILL SHIFT TO THE W...AND NW AND INCREASE DURING
THE AFTN. -SHRA WILL BE POSSIBLE ANY TIME AFT 15Z/01 AS THE SFC
LOW MOVES NORTH OF THE AIRPORT TERMINAL. VFR CIGS WILL LIKELY FALL
TO MVFR AS THE LOW MOVES CLOSER TO THE AIRPORT SITE OVERNIGHT.
/OUTLOOK FOR KMSP/
SAT EVENING...MVFR WITH -SHRA. WINDS NW AT 10G20KTS.
SUN...VFR. WINDS NNW AT 10KTS.
MON...VFR WITH -SHRA POSSIBLE LATE. WINDS ESE AT 10KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...JRB
LONG TERM...DWE
AVIATION...JLT
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
451 AM CDT FRI MAY 31 2013
.UPDATED FOR 12Z AVIATION DISCUSSION...
ISSUED AT 441 AM CDT FRI MAY 31 2013
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 330 AM CDT FRI MAY 31 2013
EARLY MORNING WATER VAPOR IMAGERY TOGETHER WITH THE PRESSURE OF THE
1.5PVU SURFACE SHOWED A NARROW RIBBON OF POTENTIAL VORTICITY
PROTRUDING DOWN TO THE 450/500MB LEVEL. THIS PV RESERVOIR
ORIGINATED UPSTREAM OFF THE BRITISH COLUMBIA COAST...EXTENDED
SOUTHEAST ACROSS THE KS/NE BORDER...AND CURLED UP OVER THE UPPER
MIDWEST. OVERLAYING THE 300MB WINDS SHOWED AN AREA OF POSITIVE
VORTICITY OWING TO THE EASTERLY WINDS OF 30KTS ON THE POLEWARD SIDE
OF +100KT WESTERLY JET. AT THE SURFACE A 991 LOW WAS LOCATED BENEATH
THE LEADING EDGE OF THE PV GRADIENT ALONG THE SD/ND BORDER...WITH A
SURFACE COLD FRONT DRAPED ON THE EASTERN SIDE OF THE MISSOURI
RIVER VALLEY.
FOR TODAY THE 00Z RUN OF THE HOPWRF AND FEW RUNS OF
THE HRRR SHOWS ANOTHER ACTIVE DAY SOUTH AND EAST OF THE CWA WITH
SEVERAL THUNDERSTORM COMPLEXES EXPECTED TO DEVELOP AS THE DEEP SHEAR
ASSOCIATED WITH THE AFOREMENTIONED UPPER LEVEL JET MOVE ACROSS THE
MISSISSIPPI RIVER VALLEY. MEANWHILE IT SHOULD BE MAINLY DRY FOR THE
FIRST HALF OF FRIDAY ACROSS THE CWA. IN FACT FORECAST SOUNDINGS VIA
THE RAP SUPPORT MOSTLY SUNNY SKIES DURING THE MORNING HOURS.
HOWEVER...WITH THE VORT MAX ROTATING OVERHEAD EXPECT INCREASING
CLOUDS WITH SHOWERS/THUNDERSTORMS AS THE ATMOSPHERE DESTABILIZES BY
MID AFTERNOON...MORESO THAN THE HIRES MODELS WOULD INDICATE. THE
BEST DEEP LAYER SHEAR WILL BE ACROSS EASTERN IOWA AND WISCONSIN...SO
SEVERE THREAT IS LOW IN MINNESOTA...BUT COULD SEE SOME STRONGER
STORMS IN WEST CENTRAL WISCONSIN. BUFR FORECAST SOUNDINGS SHOW
ROUGHLY 1000J/KG OF MLCAPE AND FREEZING LEVELS AROUND 9-10KFT
AGL...SO WOULDNT BE SURPRISED TO GET SOME SMALL HAIL AND GUSTY
WINDS WITH A FEW OF THE STRONGER CELLS. THE BEST CHANCE FOR DEEPER
CONVECTION WILL BE IN EASTERN MN AND WESTERN WI. ON FRIDAY NIGHT
THE INSTABILITY WILL DECREASE GIVING WAY TO LIGHT WINDS AND LOW
STRATUS AS THE OCCLUDED CYCLONE SLOWLY WOBBLES EASTWARD. A FEW
LIGHT RAIN SHOWERS DEVELOP ACROSS THE WESTERN HALF OF THE CWA AS
INDICATED BY THE LOW LEVEL SATURATION SHOWN IN THE BUFR SOUNDINGS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 330 AM CDT FRI MAY 31 2013
CLOSED UPPER CIRCULATION OVER THE REGION SATURDAY. IT SHOULD
PROVIDE GENERAL CLOUDINESS AND THE THREAT OF SHOWERS MUCH OF THE
DAY. AS THE CIRCULATION PIVOTS EAST NORTHEAST AND WEAKENS...MODELS
SUGGEST SOME WEAK SURFACE BASED CAPE AND SOME SLIGHTLY NEGATIVE
BEST LI`S OVER EASTERN AREAS...INTO THE AFTERNOON. WILL NEED SOME
BREAKS IN THE CLOUDS TO GENERATE ANY SIGNIFICANT DESTABILIZATION.
OPTED TO MENTION ISOLATED THUNDER OVER THE EAST PORTION OF THE
CWA...MAINLY IN THE AFTERNOON. WITH SIGNIFICANT CLOUD COVER
AROUND...TEMPERATURES MAY NOT GET OUT OF THE 50S OVER THE WEST AND
WILL REMAIN IN THE 60S EAST.
THIS INITIAL SYSTEM MOVES EAST...AND BECOMES MORE PROGRESSIVE AS
THE NEXT SIGNIFICANT TROUGH MOVES ASHORE OVER THE PACIFIC
NORTHWEST LATER SUNDAY. THIS SHOULD PROVIDE A CLEARING
TREND...ALONG WITH DRIER CONDITIONS SUNDAY INTO MONDAY. SOME
RETURN FLOW...WARM AIR ADVECTION PATTERN DEVELOPS DURING THE DAY
MONDAY...MAINLY OVER THE FAR WEST. THE WESTERN CLOSED CIRCULATION
MOVES SLOWLY EAST OVER THE REGION...AND APPEARS TO AFFECT THE AREA
FOR THE REMAINDER OF THE WEEK. THIS WILL AGAIN PROVIDE A LONG
PERIOD OF CLOUDINESS AND THE THREAT OF SHOWERS AND THUNDERSTORMS
TO THE CWA. TUESDAY AND WEDNESDAY LOOK TO BE THE WETTEST DAYS...BUT
THE SHOWERY WEATHER PATTERN WILL CONTINUE THROUGH THURSDAY. THE
BELOW NORMAL TEMPERATURE PATTERN WILL ALSO CONTINUE INTO THE
FIRST PART OF JUNE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 441 AM CDT FRI MAY 31 2013
MAINLY VFR CONDITIONS THIS MORNING...WITH AFTERNOON SHOWERS AND
THUNDERSTORMS DEVELOPING...FOLLOWED BY LOWER CIGS ACROSS THE
WEST FRIDAY NIGHT. SURFACE LOW OVER THE DAKOTAS WILL MOVE
EASTWARD...WITH MVFR CIGS POSSIBLE AT KAXN THIS MORNING. LATER
THIS AFTERNOON CLOUDS WILL INCREASE...WITH SHOWERS POSSIBLE AT
KAXN/KSTC/KRWF...AND THUNDERSTORMS AT KMSP/KRNH/KEAU. THESE WILL
TAPER OFF OVERNIGHT WHILE MVFR CIGS MOVE IN FROM THE NORTHWEST.
KMSP...
VFR CONDITIONS THIS MORNING WITH SSW WIND INCREASING. LATER THIS
AFTERNOON EXPECT TO HAVE SOME SHOWERS AND THUNDERSTORMS SCATTERED
ABOUT. BEST CHANCE WILL BE BETWEEN 22-24Z. THIS WILL BE FOLLOWED
BY VFR CONDITIONS.
/OUTLOOK FOR KMSP/
SAT...MVFR WITH -SHRA. WINDS NW AT 10G20KTS.
SUN...VFR. WINDS NNW AT 10KTS.
MON...VFR WITH -SHRA POSSIBLE LATE. WINDS ESE AT 10KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...JRB
LONG TERM...DWE
AVIATION...JRB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
330 AM CDT FRI MAY 31 2013
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 330 AM CDT FRI MAY 31 2013
EARLY MORNING WATER VAPOR IMAGERY TOGETHER WITH THE PRESSURE OF THE
1.5PVU SURFACE SHOWED A NARROW RIBBON OF POTENTIAL VORTICITY
PROTRUDING DOWN TO THE 450/500MB LEVEL. THIS PV RESERVOIR
ORIGINATED UPSTREAM OFF THE BRITISH COLUMBIA COAST...EXTENDED
SOUTHEAST ACROSS THE KS/NE BORDER...AND CURLED UP OVER THE UPPER
MIDWEST. OVERLAYING THE 300MB WINDS SHOWED AN AREA OF POSITIVE
VORTICITY OWING TO THE EASTERLY WINDS OF 30KTS ON THE POLEWARD SIDE
OF +100KT WESTERLY JET. AT THE SURFACE A 991 LOW WAS LOCATED BENEATH
THE LEADING EDGE OF THE PV GRADIENT ALONG THE SD/ND BORDER...WITH A
SURFACE COLD FRONT DRAPED ON THE EASTERN SIDE OF THE MISSOURI
RIVER VALLEY.
FOR TODAY THE 00Z RUN OF THE HOPWRF AND FEW RUNS OF
THE HRRR SHOWS ANOTHER ACTIVE DAY SOUTH AND EAST OF THE CWA WITH
SEVERAL THUNDERSTORM COMPLEXES EXPECTED TO DEVELOP AS THE DEEP SHEAR
ASSOCIATED WITH THE AFOREMENTIONED UPPER LEVEL JET MOVE ACROSS THE
MISSISSIPPI RIVER VALLEY. MEANWHILE IT SHOULD BE MAINLY DRY FOR THE
FIRST HALF OF FRIDAY ACROSS THE CWA. IN FACT FORECAST SOUNDINGS VIA
THE RAP SUPPORT MOSTLY SUNNY SKIES DURING THE MORNING HOURS.
HOWEVER...WITH THE VORT MAX ROTATING OVERHEAD EXPECT INCREASING
CLOUDS WITH SHOWERS/THUNDERSTORMS AS THE ATMOSPHERE DESTABILIZES BY
MID AFTERNOON...MORESO THAN THE HIRES MODELS WOULD INDICATE. THE
BEST DEEP LAYER SHEAR WILL BE ACROSS EASTERN IOWA AND WISCONSIN...SO
SEVERE THREAT IS LOW IN MINNESOTA AND EVEN WEST CENTRAL WISCONSIN.
BUFR FORECAST SOUNDINGS SHOW ROUGHLY 1000J/KG OF MLCAPE AND FREEZING
LEVELS AROUND 9-10KFT AGL...SO COULD SEE SOME SMALL HAIL AND GUSTY
WINDS WITH A FEW OF THE STRONGER CELLS. THE BEST CHANCE FOR DEEPER
CONVECTION WILL BE IN EASTERN MN AND WESTERN WI. ON FRIDAY NIGHT THE
INSTABILITY WILL DECREASE GIVING WAY TO LIGHT WINDS AND LOW STRATUS
AS THE OCCLUDED CYCLONE SLOWLY WOBBLES EASTWARD. A FEW LIGHT RAIN
SHOWERS DEVELOP ACROSS THE WESTERN HALF OF THE CWA AS INDICATED BY
THE LOW LEVEL SATURATION SHOWN IN THE BUFR SOUNDINGS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 330 AM CDT FRI MAY 31 2013
CLOSED UPPER CIRCULATION OVER THE REGION SATURDAY. IT SHOULD
PROVIDE GENERAL CLOUDINESS AND THE THREAT OF SHOWERS MUCH OF THE
DAY. AS THE CIRCULATION PIVOTS EAST NORTHEAST AND WEAKENS...MODELS
SUGGEST SOME WEAK SURFACE BASED CAPE AND SOME SLIGHTLY NEGATIVE
BEST LI`S OVER EASTERN AREAS...INTO THE AFTERNOON. WILL NEED SOME
BREAKS IN THE CLOUDS TO GENERATE ANY SIGNIFICANT DESTABILIZATION.
OPTED TO MENTION ISOLATED THUNDER OVER THE EAST PORTION OF THE
CWA...MAINLY IN THE AFTERNOON. WITH SIGNIFICANT CLOUD COVER
AROUND...TEMPERATURES MAY NOT GET OUT OF THE 50S OVER THE WEST AND
WILL REMAIN IN THE 60S EAST.
THIS INITIAL SYSTEM MOVES EAST...AND BECOMES MORE PROGRESSIVE AS
THE NEXT SIGNIFICANT TROUGH MOVES ASHORE OVER THE PACIFIC
NORTHWEST LATER SUNDAY. THIS SHOULD PROVIDE A CLEARING
TREND...ALONG WITH DRIER CONDITIONS SUNDAY INTO MONDAY. SOME
RETURN FLOW...WARM AIR ADVECTION PATTERN DEVELOPS DURING THE DAY
MONDAY...MAINLY OVER THE FAR WEST. THE WESTERN CLOSED CIRCULATION
MOVES SLOWLY EAST OVER THE REGION...AND APPEARS TO AFFECT THE AREA
FOR THE REMAINDER OF THE WEEK. THIS WILL AGAIN PROVIDE A LONG
PERIOD OF CLOUDINESS AND THE THREAT OF SHOWERS AND THUNDERSTORMS
TO THE CWA. TUESDAY AND WEDNESDAY LOOK TO BE THE WETTEST DAYS...BUT
THE SHOWERY WEATHER PATTERN WILL CONTINUE THROUGH THURSDAY. THE
BELOW NORMAL TEMPERATURE PATTERN WILL ALSO CONTINUE INTO THE
FIRST PART OF JUNE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1110 PM CDT THU MAY 30 2013
MAIN COMPLICATIONS WITH THIS SET ARE TWOFOLD. FIRST...THE ONGOING
CONVECTION OVER SW MN...WILL IT HOLD TOGETHER TO REACH THE
TERMINALS. SECOND...WILL THERE BE CONVECTION LATE TMRW AFTN/TMRW
EVE AT THE TERMINALS. FOR THE SW MN ACTIVITY...THE SHWRS/TSTMS ARE
MOVING INTO A REGION OF INCRD INSTABILITY AND AN ENVIRONMENT THAT
STILL HAS DEWPOINTS IN THE MID 60S. THE ACTIVITY MAY DIMINISH
SOMEWHAT IN STRENGTH...MAINLY LOSING THUNDER...BUT AM MORE THAN
MODERATELY CONFIDENT THAT SHWRS WILL REACH ALL TERMINALS OVER THE
NEXT FEW HOURS SO HAVE INCLUDED STAGGERED TEMPO GROUPS FOR MVFR
VSBY SHWRS. HAVE ALSO INCLUDED MVFR CIGS IN THE PRE-DAWN HRS
BEFORE VFR CONDS TAKE HOLD THRU MUCH OF THE DAY. GOING INTO LATE
TMRW AFTN...MOST SHORT-TERM MODELS HOLD THE NEXT BATCHES OF
CONVECTION OVER IA AND INTO FAR SW WI...WHILE THE BROADER-SCALE
MODELS INDICATE CONVECTION MAY OVERSPREAD SRN-CENTRAL MN. HAVE
PLAYED THINGS CONSERVATIVELY AND HELD OFF PRECIP MENTION ATTM TO
GIVE MORE TIME FOR MODELS TO RESOLVE THE SITUATION AND JUST
UTILIZED LOWER-END VFR CIGS. SE WINDS AT THE START GRADUALLY VEER
TO S AND SW THRU THIS TAF DURATION...AND AGAIN BECOME GUSTY TMRW
AFTN INTO TMRW EVE.
KMSP...KEPT CONDS VFR THROUGHOUT THIS SET BUT THERE ARE A FEW TIME
PERIODS WHERE MVFR CONDS ARE POSSIBLE. FIRST...CONVECTION OVER SW
MN MAY REACH MSP BETWEEN 07Z-10Z. ALTHOUGH THUNDER IS NOT
EXPECTED..SOME HEAVIER BURSTS OF RAIN MAY DROP VSBY INTO MVFR
RANGE. BEHIND THIS RAIN FOR THE REMAINDER OF THE PRE-DAWN
HRS...VFR CIGS ARE CURRENTLY ADVERTISED BUT SEEING CIGS DROP INTO
THE UPPER MVFR RANGE WOULD NOT AT ALL BE UNREASONABLE. AM NOT
THINKING CIGS DROP BELOW 2 KFT. CLOUDS THEN SCATTER OUT SHORTLY
AFTER SUNRISE AND REMAIN VFR THRU THE DAY. LOWER-END VFR CIGS
RETURN LATE IN THE DAY THEN THERE IS HIGH UNCERTAINTY REGARDING
CONVECTION RETURNING LATE AFTN THRU THE EVE HOURS. HAVE LEFT IT
OUT ATTM DUE TO LOW CONFIDENCE SO WILL LET LATER MODEL RUNS AND
TAF ISSUANCES RESOLVE THIS ISSUE.
/OUTLOOK FOR KMSP/
SAT...MVFR CIGS POSSIBLE. SHRA LIKELY. WINDS WNW 5-10 KTS.
SUN...MVFR CIGS POSSIBLE EARLY. WINDS N 5 KTS.
MON...VFR. WINDS SE 5 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...LS
LONG TERM...DWE
AVIATION...JPC
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
600 PM CDT FRI MAY 31 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 1233 PM CDT FRI MAY 31 2013
SEE MESO AFD FOR MORE DETAILS THROUGH TONIGHT. MAIN CONCERN LATE
TONIGHT WILL BE FLOODING/HYDRO ISSUES. A STRENGTHENING LOW LEVEL
JET WILL IMPINGE ON APPROACHING MESOSCALE SFC BOUNDARY. PROGGED
PWATS AROUND 1.75 INCHES WITH CONTINUED LOW LEVEL MOISTURE
ADVECTION WITH THE POTENTIAL FOR A FORWARD PROPAGATING MCS WITH
HEAVY RAINFALL DEVELOPING ON THE OUTFLOW DOMINATE PORTION OF THE
MCS SOMEWHERE OVER THE REGION WHERE STORMS CAN TRAIN ALONG A WSW-
ENE ORIENTED OUTFLOW BOUNDARY. FCST GUIDANCE HAS TARGETED THE MO
OZARK PLATEAU FOR THIS SCENARIO WITH AN EXCESS OF 3-4 INCHES OF
RAIN...BUT CONFIDENCE ON THE PRECISE LOCATION OF THE EXCESSIVE/HEAVY
RAIN WILL BE AN UNFOLDING STORM AND MESOSCALE ISSUE.
THE COLD FRONT WILL FINALLY MOVE THROUGH THE REGION SATURDAY. MAY
HAVE TO WATCH FOR SOME REDEVELOPMENT ALONG THE FRONT AS IT
EXITS...BUT WILL TACKLE THAT LATER ON.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 1233 PM CDT FRI MAY 31 2013
SUNDAY AND MONDAY WILL BE QUIET AND COOL WITH HIGH PRESSURE NOSING
SOUTH INTO THE AREA. ANOTHER UPPER LOW WILL MOVE INTO THE UPPER
PLAINS WITH EMBEDDED SHORTWAVES IN THE W-E UPPER LEVEL FLOW TOWARD
THE MID/LATE WEEK PERIOD WITH INCREASING RAIN CHANCES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1233 PM CDT FRI MAY 31 2013
CONVECTION CURRENTLY TO THE NORTH OF THE TAF SITES AT 23Z. WILL
GRADUALLY SEE THIS TRANSITION SOUTHEASTWARD TONIGHT...BUT
TRANSITION WILL BE A SLOW ONE. HRRR SEEMS TO HANDLE THIS THIS BEST
AND HAVE USED AS GUIDANCE ON TAKING PRECIPITATION SOUTH THROUGH
THE AREA TONIGHT. EXPECTING VFR CONDITIONS OUTSIDE OF CONVECTION
AND MVFR CONDITIONS WITHIN THE CONVECTION. COLD FRONT SHOULD PUSH
THROUGH THE AREA ON SATURDAY FROM NORTH TO SOUTH.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR MOZ055>058-
066>071-077>083-088>098-101>106.
KS...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR KSZ073-097-101.
&&
$$
SHORT TERM...DSA
LONG TERM...DSA
AVIATION...DSA
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
411 AM CDT Fri May 31 2013
.SHORT TERM...(Today and Tonight)
Issued at 410 AM CDT FRI MAY 31 2013
Convection early this morning will persist through sunrise, with the
potential for more storms again this afternoon. Environment across
eastern Kansas and northern Missouri remains somewhat stabilized
from the the excessive rain the region received Thursday, however a
speed max ejecting through the Central Plains early this morning has
brought considerable focus back to areas from central Kansas east
into west central Missouri. Moisture advection within the speed max
has proven more than sufficient to initiate thunderstorms early this
morning. Storms early this morning are elevated in nature, thanks to
the stable boundary layer, but source region for the speed max is,
and will continue to, tap MUCAPE values across southern Kansas and
Oklahoma around 3000 J/KG, with effective shear values ranging above
50 knots. This will make storms through the early morning hours
rather volatile, with large hail and torrential rain the primary
threats. Activity through sunrise will generally range between
Highway 50 and Highway 36, as this region will be the focus for
continued mass convergence as long as the speed max is moving
through. Speed max will be to veer off after sunrise, likely
allowing the storms to transit from intense thunderstorms into
widespread rain for several hours this morning, therefore the severe
thunderstorm watch in effect for parts of our forecast area this
morning only runs through 8 AM.
Thunderstorm activity from this morning will likely take much of the
morning to run its course, bringing more saturating rain to the
region. Potential for redevelopment is there for the afternoon hours
if this mornings storms dissipate quickly enough to allow for
surface destabilization later on. Storm initialization should get a
boost this afternoon as a front across eastern Nebraska into central
Kansas begins to sweep through northern Missouri as the parent
circulation across the Northern Plains begins to shift farther east.
However, focus for afternoon convection should set up a little
farther east and south, limiting the likely POPs to the southeastern
half of the outlook area, from east central Kansas through northeast
Missouri. Large hail and torrential rain continue to look like the
major threats later this afternoon into this evening.
.LONG TERM...(Saturday through Thursday)
Issued at 410 AM CDT FRI MAY 31 2013
Looking into the weekend, it finally appears that we will have a
small respite from the storms. Parent trough giving us our current
round of storms will finally transit far enough east to take the
focus off the Plains States. This presents us with a dry forecast
after any potential lingering storm activity Saturday morning fades
away. Currently, forecast looks dry through Monday, with below
normal temperatures --Sunday might not make it out of the 60s--.
Unfortunately, our forecast does not remain dry. By Monday night,
models are advertising the beginning of another round of rain as yet
another trough begins to swing out of the Pacific Northwest into the
Northern Plains, interacting with the shortwave ridge that will be
in place. Confidence is not high enough to say that next work week
will be like this past work week, but the potential looks to be
there for more excessive rainfall next week.
&&
.AVIATION...(For the 06Z TAFS through 06Z Friday Night)
Issued at 1220 AM CDT FRI MAY 31 2013
Scattered convection forming along a west-east band from central KS
into west central MO is likely the start of a convective complex that
will evolve overnight as the southerly low level jet over central KS
and OK ramps up. The 00z NAM and latest HRRR seem to have the nest
handle on the current situation and followed the general theme of
increasing convective activity into the terminals as we move into the pre-
dawn hours of Friday morning. With increasing confidence on a
convective complex forming have lowered ceilings into the MVFR
category with MVFR visibilities. Should the expected complex take
dead aim on any of the terminals the risk of IFR
ceilings/visibilities will increase...and most likely in the 10-13z
time period.
Should see convection drop off considerably by mid morning with
ceiling improving to VFR. Still the potential for late
afternoon/early evening re-development of convection but with
continued low confidence it will affect the KMCI/KMKC terminals.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...FLASH FLOOD WATCH through this evening FOR KSZ025-057-060-
102>105.
MO...FLASH FLOOD WATCH through this evening FOR MOZ001>008-011>017-
020>025-028>033-037>040-043>046-053-054.
&&
$$
SHORT TERM...Cutter
LONG TERM...Cutter
AVIATION...MJ
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1220 AM CDT Fri May 31 2013
.UPDATE...
Issued at 1000 PM CDT THU MAY 30 2013
Adjusted short term forecast for current radar/satellite/model
trends. Except for a few isolated cells over far nw MO and east
central KS looking quiet for a few more hours. However, already
seeing signs on satellite/radar over central KS. The rapid increase
of alto-cumulus clouds and elevated returns is signaling the rapid
redevelopment of the low level jet. The 00z NAM is noticeably
stronger with the h8 winds and this seems reasonable. The 00z NAM,
HRRR and RAP all generate rapid convective development on the nose of
the low level jet and spread it across east central KS and west
central MO during the pre-dawn hours. Heavy rains and near-severe
storms are expected between 08z-14z Friday over this region.
&&
.SHORT TERM...(This Evening through Friday)
Issued at 325 PM CDT THU MAY 30 2013
Leading edge of storms should move east of the forecast area by 4 or
so leaving just the trailing stratiform area of rainfall with
embedded convection through the early evening. So through this
evening the chances of rain/embedded storms will diminish from west
to east. The focus then shifts to tonight for the possibility of
convection erupting in eastern Kansas and then spreading into
western Missouri. There is a quite a bit of uncertainty with how
things may evolve tonight as several short-range models keep things
quiet overnight. However, the more reliable HRRR, which has been
handling today`s convection very well, has been consistent in
developing convection somewhere across northeastern Kansas and
moving into west central and northwestern Missouri. This roughly
corresponds to an area of strong isentropic lift with a focusing of
the LLJ depicted by the GFS. There should be enough instability and
shear to lead to storm organization so a few severe storms are
possible with large hail the biggest threat with damaging winds
possible as well. Will keep the flash flood watch going as is given
recent heavy rains across northern Missouri and persistent moderate
to heavy rain across the southern portions of the forecast and the
uncertainty with where any heavy rain may set up tonight. Some areas
within the watch area have good chance of seeing heavy rainfall
tonight and some much river flooding ongoing and already saturated
soils, it won`t take much more rain to lead to rapid runoff and
flash flooding.
.LONG TERM...(Friday Night through Thursday)
Issued at 325 PM CDT THU MAY 30 2013
Cold front will slide through the forecast area Friday night,
pushing the threat for thunderstorms southeast of the area.
Elongated area of high pressure will build into much of the Plains
over the weekend providing dry conditions and comfortable
temperatures. Cold air advection on Saturday and Sunday will keep
highs in the upper 60 and lower 70s.
Warm air advection on the back side of this area of high pressure
will set the stage for an increase in rain chances next week.
Initial rain chances will begin early Tuesday when a weak shortwave
will eject into the Plains ahead of a deeper wave digging into the
Upper Midwest. This system will eventually drop a cold front and
associated chances for showers and thunderstorms into the area by
mid-week, though there are still considerable model differences with
the timing of this activity.
&&
.AVIATION...(For the 06Z TAFS through 06Z Friday Night)
Issued at 1220 AM CDT FRI MAY 31 2013
Scattered convection forming along a west-east band from central KS
into west central MO is likely the start of a convective complex that
will evolve overnight as the southerly low level jet over central KS
and OK ramps up. The 00z NAM and latest HRRR seem to have the nest
handle on the current situation and followed the general theme of
increasing convective activity into the terminals as we move into the pre-
dawn hours of Friday morning. With increasing confidence on a
convective complex forming have lowered ceilings into the MVFR
category with MVFR visibilities. Should the expected complex take
dead aim on any of the terminals the risk of IFR
ceilings/visibilities will increase...and most likely in the 10-13z
time period.
Should see convection drop off considerably by mid morning with
ceiling improving to VFR. Still the potential for late
afternoon/early evening re-development of convection but with
continued low confidence it will affect the KMCI/KMKC terminals.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...FLASH FLOOD WATCH through this evening FOR KSZ025-057-060-
102>105.
MO...FLASH FLOOD WATCH through this evening FOR MOZ001>008-011>017-
020>025-028>033-037>040-043>046-053-054.
&&
$$
UPDATE...MJ
SHORT TERM...CDB
LONG TERM...Hawblitzel
AVIATION...MJ
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1158 PM CDT THU MAY 30 2013
.UPDATE...
ISSUED AT 840 PM CDT THU MAY 30 2013
CONVECTIVE TRENDS ARE PROCEEDING ABOUT AS ANTICIPATED THIS
EVENING. WHILE MUCH OF THE SHORT TERM UPDATING WILL BE REACTIVE
FOR THE REST OF THE NIGHT...GENERALLY SPEAKING I EXPECT THE LINE
OF STORMS NOW MOVING THROUGH SOUTHWEST/SOUTH CENTRAL MISSOURI TO
CONTINUE MOVING STEADILY EAST FOR THE REST OF THE EVENING INTO THE
OVERNIGHT HOURS. THE RAP CONTINUES TO SHOW A VERY STRONG LOW LEVEL
JET WITH TREMENDOUS MOISTURE CONVERGENCE OVER THE AREA FOR MUCH OF
THE REST OF THE NIGHT...AND THE HRRR SLOWS THE LINE FURTHER OVER
SOUTHERN AND EASTERN SECTIONS OF THE CWFA. IT ALSO DEVELOPS THE
CONVECTION NOW PERCOLATING OVER CENTRAL AND EASTERN KANSAS INTO
ANOTHER HEAVY RAIN PRODUCING MCS BEFORE BY 10Z AND IT MOVES EAST INTO
OUR AREA BY AROUND 12Z. DUE TO THE POTENTIAL FOR ADDITIONAL HEAVY
RAIN TONIGHT AND TOMORROW MORNING...AM GOING TO EXPAND THE FLASH
FLOOD WATCH TO THE REMAINDER OF THE AREA STARTING IMMEDIATELY AND
CONTINUING TO 12Z SATURDAY.
CARNEY
&&
.SHORT TERM...(THROUGH LATE TONIGHT)
ISSUED AT 240 PM CDT THU MAY 30 2013
TORNADO WATCH CONTINUES UNTIL 8 PM. ATMOSPHERE OUTSIDE OF OUTFLOW
COOLED AIR HAS BECOME QUITE UNSTABLE WITH MLCAPES ABOVE 2000 J/KG.
AT THE SAME TIME...DEEP LAYER SHEAR IS INCREASING IN RESPONSE TO
APPROACHING TROUGH CURRENTLY OVER THE CENTRAL PLAINS. THIS TROUGH
IS THE MAIN FOCUS FOR LARGE SCALE ASCENT TONIGHT AND CONSEQUENTLY IT
WILL DETERMINE THE OVERALL PRECIPITATION TRENDS. RAP SHOWS THIS
TROUGH MOVING ACROSS THE CWA AROUND 06Z...SO CURRENT THINKING IS
THAT LINE OF STORMS OVER WESTERN MO WILL CONTINUE TO SLOWLY MOVE
EAST ACROSS THE AREA LATER THIS AFTERNOON AND EVENING.
AFOREMENTIONED INSTABILITY AND SHEAR STILL FAVORS THE POTENTIAL FOR
A FEW SUPERCELLS OR ORGANIZED MULTI-CELLS THAT COULD PRODUCE LARGE
HAIL AND DAMAGING WINDS. LOW LEVEL SHEAR ALSO SUGGESTS THAT ONE OR
TWO TORNADOES COULD FORM IN THE STRONGER STORMS. STILL LOOKS
REASONABLE THAT WESTERN MO LINE WILL EXIT THE EASTERN COUNTIES LATER
THIS EVENING. OUTFLOW FROM THE LINE WILL LIKELY STALL OVER SOUTHERN
MO...SO KEPT CHANCE OF THUNDERSTORMS GOING IN THE SOUTHERN CWA INTO
THE OVERNIGHT HOURS. STILL EXPECT REDEVELOPMENT OF THUNDERSTORMS
OVER WESTERN MO ON THE NOSE OF THE LOW LEVEL JET OVERNIGHT THAT WILL
MOVE INTO NORTHEAST AND CENTRAL MO TOWARD 12Z.
FLASH FLOOD WATCH WILL CONTINUE AS IS. HEAVIEST RAINFALL WILL FOCUS
OVER THE WATCH AREA TONIGHT AND THE SOUTHERN AND EASTERN COUNTIES
HAVE HIGH FLASH FLOOD GUIDANCE. ATMOSPHERE IS VERY MOIST AND DEEP
LAYER FLOW FAVORS TRAINING TONIGHT.
.LONG TERM...(FRIDAY THROUGH NEXT THURSDAY)
ISSUED AT 240 PM CDT THU MAY 30 2013
CONVECTIVE TRENDS ARE SOMEWHAT UNCLEAR FOR FRIDAY MORNING. SOME
GUIDANCE SHOWS LINGERING CONVECTION ACROSS THE EASTERN OZARKS AND
SOUTHERN ILLINOIS. THIS COULD BE POSSIBLE IF THE AFOREMENTIONED OUTFLOW
BOUNDARY FROM THURSDAY NIGHT`S CONVECTION IS STILL IN PLACE OVER
THOSE AREAS. HOWEVER...MOST OF THE GUIDANCE SHOWS A DRYING TREND
BY AROUND 12Z ACROSS THE AREA. THEN...THE LOW LEVEL JET REFOCUSES
BACK OVER NORTHERN/NORTHWESTERN MISSOURI. ALL GUIDANCE SHOWS A
TREMENDOUS AMOUNT OF MOISTURE CONVERGENCE IN THAT AREA STARTING
ABOUT 12Z AND RAIN DEVELOPING BETWEEN 12Z AND 15Z...SPREADING INTO
NORTHEAST MISSOURI/WEST CENTRAL ILLINOIS PROBABLY DURING THE MID
TO LATE MORNING. INSTABILITY WILL BUILD RAPIDLY DURING THE LATE
MORNING WITH MUCAPE EXCEEDING 2500 J/KG ACCORDING TO MOST GUIDANCE
AND DEEP LAYER SHEAR AROUND 50-60KTS SO SEVERE STORMS WILL BE
POSSIBLE AT ANY TIME DURING THE LATE MORNING. HOWEVER...THE MAIN
SHOW WILL LIKELY DEVELOP DURING THE LATE AFTERNOON OR EARLY
EVENING AS ANOTHER LOBE OF VORTICITY WRAPS AROUND THE SOUTH SIDE
OF THE UPPER LEVEL LOW AND PUSHES THE SURFACE FRONT INTO NORTHWEST
MISSOURI. WHATEVER`S LEFT OF THE CAP WILL ALSO BE WIPED AWAY.
AFTERNOON CAPE VALUES LOOK TO BE IN EXCESS OF 3000 J/KG WITH SHEAR
STAYING ABOVE 50KTS. THINK THERE WILL BE SOME DISCRETE STORMS
INITIALLY...BUT WITH LITTLE OR NO CAP AND COPIOUS CAPE WE SHOULD
SEE THE STORMS CONGEAL INTO A LINE. CANNOT RULE OUT ANY KIND OF
SEVERE WEATHER INCLUDING DAMAGING WINDS...LARGE HAIL...AND EVEN
TORNADOES WITH THE LINE. THE LINE SHOULD PROGRESS AT A MODERATE
PACE INTO SOUTHEAST MISSOURI BY EARLY MORNING SATURDAY. OF COURSE
WITH THE HEAVY RAIN POTENTIAL AND NEARLY SATURATED GROUND THERE
WILL BE A CONTINUING FLASH FLOOD THREAT...AND IT`S LIKELY THE
FLASH FLOOD WATCH WILL NEED TO BE EXPANDED EITHER EARLY FRIDAY
MORNING OR FRIDAY AFTERNOON TO COVER THE REST OF THE CWFA.
CURRENT THINKING IS THAT THE INITIAL LINE OF CONVECTION WILL WEAKEN
OVER THE EASTERN OZARKS SATURDAY MORNING. HOWEVER THERE WILL BE
REDEVELOPMENT BY EARLY SATURDAY AFTERNOON...PERHAPS AS FAR NORTHWEST
AS THE COLUMBIA AREA...AS THE SURFACE COLD FRONT FINALLY KICKS INTO
GEAR AND HEADS EAST. SPC STILL HAS THE SOUTHEASTERN 2/3 OF THE CWFA
IN A SLIGHT RISK SATURDAY...INCLUDING THE STL METRO AREA AND POINTS
ALONG AND EAST OF THE I-44/I-55 CORRIDORS. THE UPPER LEVEL
SHORTWAVE FINALLY SWINGS THROUGH SATURDAY AFTERNOON/EARLY EVENING
PUSHING THE COLD FRONT SOUTHEAST INTO THE LOWER
MISSISSIPPI/TENNESSEE VALLEYS.
(SUNDAY THROUGH NEXT THURSDAY)
HIGH PRESSURE IS STILL EXPECTED TO BUILD ACROSS THE MIDWEST SUNDAY
AND CONTROL THE WEATHER AT LEAST THROUGH MONDAY. EXPECTING BELOW
NORMAL TEMPERATURES AND LESS HUMID CONDITIONS THROUGH THAT PERIOD.
MEDIUM RANGE GUIDANCE IS A LITTLE FASTER THAN YESTERDAY IN PUSHING
THE HIGH EAST AWAY FROM THE MID-MISSISSIPPI VALLEY. SOUTHERLY FLOW
RETURNS TUESDAY AND BOTH THE GFS AND ECMWF PRINT OUT PRECIP LATE
TUESDAY THROUGH THURSDAY AS A SHORTWAVE DIPS INTO THE NORTHERN
PLAINS. THE GFS IS MUCH MORE DYNAMIC WITH THIS WAVE THAN THE ECMWF
AND THEREFORE CRANKS OUT A LOT MORE PRECIP. HAVE OPTED TO JUST
STICK WITH CHANCE POPS FOR THIS PERIOD RIGHT NOW. WILL CONTINUE TO
WATCH THIS NEXT WAVE AND INCREASE POPS AS NEEDED IF BOTH MODELS
CONTINUE TO TREND WETTER.
CARNEY
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1157 PM CDT THU MAY 30 2013
LO STRATUS TRYING TO FORM IN VERY MOIST LO LEVEL ENVIRONMENT AND
IT IS LOOKING INCREASINGLY LIKELY IT WILL SUCCEED. INITIAL BATCHES
ARE OUT IN CNTRL MO BUT SHOULD EXPAND WITH TIME TO ENCOMPASS ALL
THE TAF SITES BY DAYBREAK. HAVE ADDED LO-END MVFR OR IFR CIGS TO
ALL TAFS. AFTER THAT...SHOULD SEE CONDITIONS IMPROVE SOME HEADING
INTO LATE FRIDAY MORNING AS STRATUS GIVES WAY TO DIURNAL CU
FIELD...AND LIKE THURSDAY...SHOULD GO BKN PRETTY QUICK AND
INITIALLY BE MVFR CATEGORY. FURTHER IMPROVMENT TO VFR DURING
AFTERNOON SEEMS LIKELY. PCPN TRENDS...LATEST BATCH OF RAIN EXITING
STL METRO NOW AND WILL COMPLETELY EXIT BY 07Z...WITH ANOTHER TSRA
COMPLEX TRYING TO FORM OVER ERN KS AND FAR WRN MO. SHOULD SEE THIS
MATURE LATE TONIGHT AND BEGIN MAKING AN APPROACH TO KCOU AROUND
DAYBREAK AND KUIN DURING MID-MORNING. EVENTUALLY...THIS SHOULD
EXPAND AS IT ENTERS A DE-STABILIZING ATMOSPHERE AHEAD OF IT AND
MUCH LIKE THURSDAY...THE MAIN BODY OF IT PUSH INTO STL METRO
DURING FRIDAY EVENING. THIS SHOULD LINGER TO SOME EXTENT WELL INTO
THE NIGHT FOR ALL THE TAF SITES...ALTHOUGH THE WORST SHOULD HAVE
PUSHED TO THE SE BY LATE FRIDAY NIGHT.
SPECIFICS FOR KSTL...LO STRATUS LOOKS INCREASINGLY LIKELY BY
DAYBREAK...BUT SHOULD GIVE WAY TO DIURNAL CU AT SOMEWHAT HIGHER
BASES LATE FRIDAY MORNING...NEXT ROUND OF RAIN SHOULD HOLD OFF
AGAIN UNTIL FRIDAY EVENING ALTHOUGH CAN/T FULLY RULE OUT AN ISOLD
OCCURRENCE AHEAD OF IT IN THE MOIST AND UNSTABLE AIRMASS.
TES
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR AUDRAIN MO-BOONE
MO-CALLAWAY MO-COLE MO-CRAWFORD MO-FRANKLIN MO-GASCONADE MO-
IRON MO-JEFFERSON MO-KNOX MO-LEWIS MO-LINCOLN MO-MADISON MO-
MARION MO-MONITEAU MO-MONROE MO-MONTGOMERY MO-OSAGE MO-PIKE
MO-RALLS MO-REYNOLDS MO-SHELBY MO-ST. CHARLES MO-ST.
FRANCOIS MO-ST. LOUIS CITY MO-ST. LOUIS MO-STE. GENEVIEVE
MO-WARREN MO-WASHINGTON MO.
IL...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR ADAMS IL-BOND IL-
BROWN IL-CALHOUN IL-CLINTON IL-FAYETTE IL-GREENE IL-JERSEY
IL-MACOUPIN IL-MADISON IL-MARION IL-MONROE IL-MONTGOMERY IL-
PIKE IL-RANDOLPH IL-ST. CLAIR IL-WASHINGTON IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
823 PM MDT SAT JUN 1 2013
.UPDATE...
A PRETTY QUIET NIGHT IS IN STORE EVEN AS THE HEIGHTS BEGIN FALLING
A BIT ALOFT IN ADVANCE OF THE 500-HPA SHORT WAVE TROUGH NOTED OVER
SOUTHERN BRITISH COLUMBIA THIS EVENING. OTHER THAN SOME HIGH-LEVEL
CLOUDS CROSSING THE AREA...THE ONLY OTHER ITEM OF NOTE WILL BE THE
20 TO 30 PERCENT CHANCE OF SHOWERS AFTER 06 UTC FROM HARLOWTON AND
JUDITH GAP OVER TOWARD RYEGATE. WEAK MID-LEVEL INSTABILITY AND THE
PRESENCE OF A WEAK LOW-LEVEL JET IN THAT AREA SUPPORT THE CHANCES.
WE DID PULL THE ADVERTISED SLIGHT CHANCE OF SHOWERS ANOTHER ROW OF
COUNTIES SOUTH OF THE PREVIOUS FORECAST OUT OF RESPECT TO THE SREF
FROM 21 UTC AND THE POSITION OF WEAK MID-LEVEL INSTABILITY ON SOME
RECENT RAP RUNS. OTHERWISE...ONLY MINOR CHANGES WERE MADE WITH THE
UPDATE TO TONIGHT/S FORECAST. SCHULTZ
&&
.SHORT TERM...VALID FOR SUN AND MON...
THE NEXT SYSTEM THAT WILL AFFECT THE AREA WAS PUSHING ONSHORE
INTO WA AND S BC PER WATER VAPOR IMAGERY THIS AFTERNOON. THE
MODELS WERE IN GOOD AGREEMENT WITH THE TRACK OF THE UPPER LOW.
UPPER DIFLUENCE AND SHORTWAVE ENERGY WILL MOVE OVER THE AREA ON
SUN. THE UPPER LOW WILL REACH N CENTRAL MT BY 12Z MON AND WILL
MOVE SLOWLY E THROUGH THE STATE THROUGH 12Z TUE. A SHORTWAVE WILL
ACCOMPANY THE LOW AND PUSH A COLD FRONT THROUGH THE AREA SUN NIGHT
THROUGH MON MORNING. MUCH COOLER AIR WILL SPILL S INTO THE REGION
BEHIND THE SYSTEM BY TUE MORNING. SOME MOISTURE WILL REACH THE NW
FRINGES OF THE FORECAST AREA BY SUN MORNING IN THE AREA OF UPPER
DIFLUENCE SO HAVE ADDED POPS TO THIS AREA LATE TONIGHT THROUGH SUN
MORNING. MODELS WERE IN DECENT AGREEMENT IN DEVELOPING
PRECIPITATION OVER THE WESTERN ZONES SUN AFTERNOON SO HAD CHANCE
TO LIKELY POPS THERE. CHANCES FOR PRECIPITATION WILL SPREAD E SUN
EVENING AS STRONG FRONTOGENESIS PUSHES INTO THE AREA. THE HIGHEST
QPF LOOKS TO BE OVER THE NW CORNER OF THE AREA. AROUND A HALF INCH
OF QPF WILL BE POSSIBLE IN THIS AREA SUN EVENING. WHILE SHEAR WILL
BE FAVORABLE FOR STRONG THUNDERSTORMS SUN AFTERNOON AND
EVENING...CAPE VALUES WERE VERY LOW...SO WILL NOT MENTION ANY
STRONG OR SEVERE STORMS FOR NOW. RAISED HIGH TEMPERATURES A LITTLE
ON SUN.
BEST PRECIPITATION CHANCES WILL BE ACROSS THE NORTHERN ZONES LATE
SUN NIGHT THROUGH MON MORNING IN THE VICINITY OF THE EASTWARD
MOVING LOW. THE SHORTWAVE WILL SWEEP THROUGH THE AREA MON
AFTERNOON BRINGING A GOOD CHANCE OF PRECIPITATION. CHANCES FOR
PRECIPITATION WANE MON NIGHT AS ENERGY MOVES E OF THE AREA.
TEMPERATURES WILL CHALLENGING ON MON DUE TO THE FRONTAL PASSAGE.
CONTINUED THE FORECAST OF READINGS IN THE 60S. THREAT FOR STRONG
STORMS LOOKED MINIMAL FOR MON AS STRONG SHEAR QUICKLY EXITS THE
AREA AS THE COLD FRONT MOVES E. CAPE VALUES WERE ALSO NOT VERY
HIGH. ARTHUR
.LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT...
MEDIUM RANGE GUIDANCE IN OVERALL GOOD AGREEMENT. AN UPPER LOW OVER
NORTH DAKOTA ON TUESDAY WILL RESULT IN CYCLONIC FLOW BACK ACROSS
EASTERN MT. A FEW SHOWERS WILL REMAIN POSSIBLE IN AN UNSTABLE
NORTHWEST FLOW...BUT ONLY LOW SCATTERED THREAT AS MAIN IMPACTS
SHOULD STAY ACROSS NORTHERN MT WITH SOUTHERN MT BATTLING WITH THE
DOWNSLOPE FLOW. WEDNESDAY INTO EARLY THURSDAY...SHORT WAVE
RIDGING MOVES ACROSS FOR MOSTLY DRY CONDITIONS AND WARMER
CONDITIONS. AS UPPER RIDGING BUILDS ACROSS WEST COAST FOR
LATE IN THE WEEK INTO SATURDAY...AN UNSTABLE NORTHWEST FLOW
DOMINATES THE NORTHERN ROCKIES WITH A SERIES OF WAVES OFFERING UP
PRECIP CHANCES BEGINNING LATE THURSDAY INTO SATURDAY. RIGHT
NOW...BEST CHANCES APPEAR TO BE LATE FRIDAY INTO SATURDAY AND SO
HAVE RAISED PRECIP CHANCES FOR THIS TIMEFRAME. WARMEST DAY
SETTING UP FOR THURSDAY...THEN COOLER UNDER UNSTABLE NORTHWEST
FLOW. HAVE TRENDED TEMPERATURES DOWN SEVERAL DEGREES DEEP INTO
EXTENDED. FRIEDERS
&&
.AVIATION...
VFR CONDITIONS WILL GENERALLY PREVAIL OVERNIGHT WITH SOME MID- AND
HIGH-LEVEL CLOUDS CROSSING THE AREA. THERE IS A SMALL CHANCE FOR A
SHOWER AROUND K3HT BETWEEN 06 AND 18 UTC. A BETTER CHANCE FOR SOME
SHOWERS AND THUNDERSTORMS AND POSSIBLY MVFR CONDITIONS WILL ARRIVE
IN SOUTH CENTRAL MT BY LATE SUNDAY AFTERNOON. SCHULTZ
&&
.PRELIMINARY POINT TEMP/POPS...
SUN MON TUE WED THU FRI SAT
-----------------------------------------------------------
BIL 049/075 050/067 042/064 047/071 052/075 053/072 054/073
11/B 64/T 32/T 10/B 11/B 14/T 43/T
LVM 043/073 043/065 037/062 039/071 045/073 046/070 047/071
13/T 55/T 33/T 21/U 12/T 24/T 43/T
HDN 046/078 049/070 042/065 044/072 050/075 053/072 054/073
11/B 34/T 32/T 10/B 01/B 13/T 33/T
MLS 047/076 051/065 043/064 045/070 051/074 053/074 054/072
00/B 57/T 43/T 20/B 01/U 13/T 44/T
4BQ 043/076 046/069 041/062 044/068 047/073 051/075 052/070
00/B 23/T 32/T 10/B 01/U 14/T 44/T
BHK 041/070 046/065 041/060 041/065 046/070 049/073 050/068
00/B 45/T 44/T 22/W 11/B 13/T 44/T
SHR 042/076 048/069 039/062 041/067 045/075 048/071 049/071
00/B 24/T 33/T 21/B 12/T 24/T 43/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
711 PM CDT SAT JUN 1 2013
.UPDATE...
ISSUED AT 710 PM CDT SAT JUN 1 2013
ONLY MADE A FEW FAIRLY MINOR TWEAKS TO THE FORECAST FOR THE EARLY
EVENING UPDATE. FIRST OF ALL...SLIGHTLY SLOWED THE DECREASE IN
WIND SPEEDS THIS EVENING...AS MANY SITES CONTINUE TO REPORT
SUSTAINED SPEEDS OF 20+ MPH...AND IT LOOKS LIKE SUSTAINED SPEEDS
TO AROUND 15 MPH MAY STILL BE PRESENT ACROSS MUCH OF THE EASTERN
1/2 OF THE CWA EVEN AT 10 PM WITH LOWER VALUES IN THE WEST...ALTHOUGH
ALL AREAS SHOULD LEGITIMATELY SETTLE TO AROUND/UNDER 10 MPH BY
MIDNIGHT OR SO AS HIGH PRESSURE CONTINUES BUILDING IN. GIVEN THAT
SUSTAINED SPEEDS ARE ALREADY SAFELY UNDER 30 MPH IN ALL
AREAS...WILL BE REMOVING WIND WORDING FROM THE HAZARDOUS WEATHER
OUTLOOK...RESULTING IN NO HAZARD MENTION FOR THE REST OF THE NIGHT
AS THE REGION CONTINUES ITS FAIRLY BRIEF RESPITE FROM THUNDERSTORM
ACTIVITY. THE OTHER TRICKY ISSUE FOR THE OVERNIGHT HOURS WILL BE
THE FATE OF THE LOW STRATUS DECK GENERALLY IN THE 3000-5000 FT
RANGE. CURRENT EXPECTATION IS FOR A STEADY EROSION OF THIS STRATUS
FROM WEST TO EAST AS THE EVENING GOES ON...MUCH IN LINE WITH
CURRENT FORECAST. HOWEVER...WILL HAVE TO SEE IF THE 21Z RAP MAY BE
ONTO SOMETHING WITH ITS 900 MILLIBAR RELATIVE HUMIDITY FIELD...AS
IT SUGGESTS THAT QUITE A BIT OF LOW CLOUD COVER COULD HANG ON OR
MOVE BACK INTO PRIMARILY THE EASTERN 1/2 OF THE CWA
TONIGHT...WHICH COULD OBVIOUSLY HAVE AT LEAST A SLIGHT IMPACT ON
OVERNIGHT LOW TEMPS. NO CHANGES MADE TO LOW TEMPS AT THIS
TIME...WHICH ARE STILL LOOKING TO AVERAGE AROUND 10 DEGREES BELOW
NORMAL IN THE LOW-MID 40S FOR MUCH OF THE CWA. HOWEVER...PLEASE
NOTE THAT FORECAST LOWS FOR OUR PRIMARY CLIMATE SITES GRAND
ISLAND/HASTINGS ARE STILL 5 DEGREES ABOVE RECORD LOWS FOR JUNE
2ND...WHICH FOR GRAND ISLAND IS 39 IN 1964...AND HASTINGS IS 40 IN
1964/1951.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 247 PM CDT SAT JUN 1 2013
UPPER AIR PROFILER AND SATELLITE DATA THIS AFTERNOON SHOWING THE
MAIN TROUGH AXIS CONTINUING TO GRADUALLY MAKE ITS WAY EAST/SOUTHEAST
THROUGH THE PLAINS...WITH NORTHWESTERLY FLOW BUILDING IN BEHIND. AS
EXPECTED...THIS DISTURBANCE BROUGHT A FEW SPRINKLES TO THE AREA
/MAINLY THIS MORNING/...AND HAS KEPT PLENTY OF CLOUD COVER AROUND
THROUGH THE DAY. HAS ALSO BEEN A BREEZY/WINDY DAY...WHILE SURFACE
LOW PRESSURE OVER MN/WI HAS BEEN SLOW TO SHIFT EAST...HIGH PRESSURE
HAS CONTINUED TO BUILD IN FROM THE WEST BEHIND THE MAIN FRONT. THIS
TIGHTENED PRESSURE GRADIENT RESULTED IN SUSTAINED WINDS OF 20 TO 30
MPH...AND AT TIMES GUSTS IN THE 40 MPH AREA. DID HAVE SOME SITES ON
OCCASION HITTING WIND ADV CRITERIA.
THROUGH THE REST OF THE SHORT TERM PERIOD...THE FORECAST REMAINS
DRY. MODELS REMAIN IN GOOD AGREEMENT IN THE UPPER LEVELS...SHOWING
BROAD RIDGING SETTING UP OVER THE ROCKIES/PLAINS...BETWEEN AREAS OF
LOW PRESSURE LOCATED OVER ONTARIO AND THE ID/MONT/CANADIAN BORDER
REGION. THIS WILL KEEP ANY PRECIPITATION CHANCES WELL OUT OF THE
CWA...AND HELP MAKE FOR A VERY PLEASANT SUNDAY.
AT THE SURFACE...THE PATTERN THROUGH THE SHORT TERM WILL BE
DOMINATED BY HIGH PRESSURE. THIS FEATURE WILL CONTINUE TO BUILD IN
FROM THE WEST TONIGHT...AND THERE IS A LITTLE UNCERTAINTY WITH JUST
HOW FAR EAST THE RIDGE AXIS WILL GET. THE NAM IS ON THE FURTHEST
EAST SIDE OF THINGS...SHOWING THE RIDGE AXIS ACTUALLY THROUGH THE
CWA BY 12Z SUNDAY...WITH MOST OF THE SUPPORT SHOWING THE RIDGE AXIS
STAYING JUST TO/SET UP OVER THE WRN FRINGE OF THE CWA. WINDS WILL
BE DIMINISHING WITH TIME...BUT DEPENDING ON WHERE THE RIDGE SETS UP
WILL DETERMINE WHETHER WINDS BECOME CALM...AND COULD AFFECT LOW
TEMPERATURES TONIGHT. STAYED FAIRLY CLOSE TO GUIDANCE FOR
LOWS...WHICH BRING LOWER/MID 40S TO THE CWA. IF THE WINDS STAY
UP...THIS MAY BE TOO COOL.
SUNDAY...SHOULD SEE PLENTY OF SUNSHINE ACROSS THE AREA...WITH THE
SURFACE HIGH KEEPING WINDS LIGHT. SHOULD START TO SEE AN INCREASE
IN TEMPS ALOFT STARTING TO SHIFT IN FROM THE WEST...AND HIGHS ARE
EXPECTED TO REACH INTO THE LOWER/MID 70S /COMBINED WITH DEWPOINTS
ONLY IN THE 40S/.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 247 PM CDT SAT JUN 1 2013
AS SFC RIDGE CONTINUES TO DEPART TO THE EAST AND SFC LOW DEEPENS
ALONG THE HIGH PLAINS...SOUTHERLY LLVL FLOW INCREASES SUNDAY
NIGHT. THE LLVL JET STRENGTHENS TO NEAR 50KTS AND IN INCREASING
SOUTHERLY FLOW...MOISTURE AGAIN IS DRAWN NORTH INTO THE PLAINS
STATES SUNDAY NIGHT/MONDAY. WARM FRONT LIFTS NORTHEAST ON MONDAY
AND TEMPS WILL TREND WARMER...CLOSER TO SEASONAL READINGS IN THE
UPPER 70S/LOW 80S. MONDAY WILL NOT BE WITHOUT WIND HOWEVER AS SFC
GRADIENT REMAINS TIGHT AND FORECAST SOUNDINGS SUGGEST MIXING TO AT
LEAST H8. WINDS DO NOT APPEAR TO REACH WIND ADV CRITERIA JUST YET...BUT
WILL NEED TO MONITOR. DURING THE DAY ON MONDAY SHOULD REMAIN
DRY...HOWEVER DID HOLD ONTO SOME LOW POPS IN THE WAA REGIME...BUT
GENERALLY EXPECT CAPPING TO HOLD IN THE EAST DURING THE AFTN WHILE
BETTER CONVECTIVE POTENTIAL/INITIATION FOCUSES TO THE WEST ALONG
THE HIGH PLAINS ALONG SFC TROUGH/DRYLINE EDGING INTO SW
NEB/WESTERN KANSAS...AND TO THE NW ALONG SFC TROUGH/COOL FRONTAL
BOUNDARY. CONVECTION IS THEN EXPECTED TO PUSH SOUTH AND EASTWARD
MONDAY NIGHT AS THE NORTHERN BOUNDARY REACHES CENTRAL NEBRASKA
AHEAD OF THE UPPER TROUGH IN THE DAKOTAS. AN INSTABILITY AXIS OF
2000 TO 2500 J/KG WILL REACH CENTRAL NEB MONDAY NIGHT WITH SHEAR
OF 30 TO 40KTS...AND SEVERE STORMS ARE POSSIBLE IN THIS
ENVIRONMENT MONDAY NIGHT...WITH HAIL/WIND PRIMARY HAZARDS FOR THE
MAINLY NOCTURNAL CONVECTION.
TUESDAY MAY SEE ONGOING CONVECTION IN THE MORNING WITH OUTFLOW
BOUNDARY AND/OR SFC WARM FRONTAL BOUNDARY POTENTIALLY STALLING
OUT...BUT THIS WILL BE DEPENDENT ON CONVECTION MONDAY NIGHT. MOISTURE
POOLS ALONG THE BOUNDARY ON TUESDAY WITH SREF INDICATING
INSTABILITY OF 3000 TO 4000 J/KG ACROSS NORTH CENTRAL KS WITH
INSTABILITY AXIS EXTENDING INTO SC NEB...WITH SHEAR ON THE ORDER
OF 40KTS. IF BOUNDARY POSITION IS CLOSE/ACROSS OUR CWA...STORMS
ARE EXPECTED TO INITIATE ACROSS OUR AREA TUESDAY AFTN/EVE IN VCNTY
OF BOUNDARY WITH SEVERE STORMS AGAIN LIKELY. SETUP WOULD BE
FAVORABLE FOR LARGE HAIL/DAMAGING WINDS/TORNADOES NEAR THE
BOUNDARY...AND HEAVY RAINFALL. ADDITIONAL CONVECTIVE DEVELOPMENT
IS POSSIBLE ALONG THE HIGH PLAINS/DRY LINE AREA AND TO THE NW WITH
APPROACHING TROUGH/SECONDARY COOL FRONT.
BEYOND THIS TIME FRAME...TOO DIFFICULT TO TRY TO NAIL DOWN THE
DETAILS AS BOUNDARY PLACEMENT WILL BE DEPENDENT UPON CONVECTION
WHICH DEVELOPS EACH DAY/NIGHT. ON WEDNESDAY...FRONT MAY LINGER IN
OUR SOUTHEAST ZONES...THEN BETTER CHCS FOR STORMS BEGIN TO SHIFT SE
ALONG BOUNDARY WHILE THE UPPER SYSTEM/LOW REACHES THE UPPER
MIDWEST. IN THEORY WE SHOULD SEE A LULL/BREAK IN CONVECTION
POTENTIAL FOR A PERIOD OR TWO...THEN PATTERN LOOKS ACTIVE AGAIN
HEADING INTO NEXT WEEKEND. FOR TEMPERATURES...IT IS NOT LOOKING
OVERLY WARM OR COLD...WITH HIGHS DEPENDENT UPON WHICH SIDE OF
BOUNDARY YOU ARE ON...BUT CLOSE TO SEASONAL NORMALS OVERALL.
&&
.AVIATION...(FOR THE 00Z KGRI TAF THROUGH 00Z SUNDAY EVENING)
ISSUED AT 640 PM CDT SAT JUN 1 2013
THE WINDS ARE EXPECTED TO TAPER DOWN THIS EVENING AS HIGH PRESSURE
BUILDS INTO THE AREA. CURRENT VISIBLE SATELLITE TRENDS SHOW MVFR CEILINGS
SLOWLY MOVING EAST AND LOOK TO SCATTER OUT IN THE NEXT FEW HOURS.
A FEW MODELS BRING MVFR CEILINGS BACK INTO NIGHT...WILL
MONITOR...CURRENTLY LEANING TOWARDS KEEPING THEM OUT OF THE TAF.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...PFANNKUCH
SHORT TERM...ADO
LONG TERM...FAY
AVIATION...BEDA
AREA FORECAST DISCUSSION
NWS HASTINGS NE
322 PM CDT FRI MAY 31 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 319 PM CDT FRI MAY 31 2013
IN THE SYNOPTIC SCALE...THE LARGE UPPER LEVEL LOW PRESSURE SYSTEM
THAT HAS AFFECTED OUR WEATHER THE PAST FEW DAYS...CONTINUES TO SPIN
ACROSS THE DAKOTAS...WHILE RIDGING CONTINUES JUST OFF BOTH THE
WESTERN AND EASTERN COASTS. IN THE MID LEVELS...THIS SYSTEM
CONTINUES TO SURGE AN ABUNDANCE OF GULF COAST MOISTURE UP THE
MISSISSIPPI RIVER VALLEY INTO THE MIDWEST...AS SEEN IN RECENT
FLOODING ASSOCIATED WITH THUNDERSTORMS ACROSS THE COUNTRY`S
MIDSECTION. AT THE SURFACE...THE SYSTEM REMAINS NEARLY VERTICALLY
STACKED WITH LOW PRESSURE ALSO ALIGNED OVER THE DAKOTAS...AND A
SECONDARY LOW SITUATED SOUTH OF THE TROUGH AXIS ACROSS SOUTHEASTERN
KANSAS.
AS THE LOW PRESSURE SYSTEM CONTINUES TO SPIN...ALMOST NEARLY
STATIONARY...THE MAIN COLD FRONTAL BOUNDARY HAS ALREADY SHIFTED
THROUGH THE OUTLOOK AREA. HOWEVER...IT APPEARS A SECONDARY WEAK
TROUGH AXIS WILL ALSO SHIFT THROUGH THE AREA OVERNIGHT TONIGHT. WITH
THIS BOUNDARY...CONCERNS IN THE SHORT TERM WILL FOCUS MAINLY ON
PRECIPITATION CHANCES AND COOLER HIGH TEMPERATURES TOMORROW.
STARTING OFF THIS AFTERNOON...WATER VAPOR IMAGERY INDICATES THE
PRESENCE OF A WEAK SHORT WAVE TROUGH SLIDING THROUGH EASTERN
COLORADO SOUTH OF THE UPPER LEVEL LOW. AN AREA OF CUMULUS HAVE
DEVELOPED ACROSS THE AREA...AND BEGUN TO SPREAD NORTHEAST AS SEEN ON
VISIBLE SATELLITE. RADAR ALSO INDICATES AT LEAST SOME VERY LIGHT
RETURNS ACROSS NORTHWEST AND NORTH CENTRAL KANSAS. WENT AHEAD AND
PUT IN SLIGHT CHANCE POPS ACROSS NORTH CENTRAL KANSAS THROUGH THE
AFTERNOON...AS BOTH THE HRRR AND NAM MODEL SEEM TO BE HANDLING THIS
WELL. NOT EXPECTING MUCH MORE THAN A COUPLE SPRINKLES AND MAYBE A
RUMBLE OF THUNDER.
HEADING INTO THE OVERNIGHT HOURS...LATEST SATELLITE IMAGERY SHOWS
THE DEVELOPMENT OF A CUMULUS FIELD ACROSS MUCH OF NORTHWESTERN
NEBRASKA JUST BEHIND THE SECONDARY TROUGH AXIS. EXPECT THIS TROUGH
AXIS TO SLIDE THROUGH THE OUTLOOK AREA ROUGHLY AROUND 6Z...WITH WEST
WINDS SHIFTING TO THE NORTHWEST. CONTINUED SLIGHT POPS FOR THE
NORTHERN HALF OF THE OUTLOOK AREA OVERNIGHT...AS BOTH THE NAM AND
HRRR INDICATE AT LEAST SOME LIGHT SHOWERS TO PUSH THROUGH. THE UPPER
LEVEL LOW WILL FINALLY BEGIN TO SHIFT EASTWARD BY SATURDAY...THUS
DECREASING POPS FROM SOUTHWEST TO NORTHEAST THROUGHOUT THE DAY.
INSTABILITY THROUGHOUT MUCH OF THE SHORT TERM PERIOD...REMAINS
FAIRLY MINIMAL...WITH ONLY ABOUT 100 J/KG OR SO AT MOST. CONTINUED
WITH MENTION OF ONLY LIGHT RAIN SHOWERS AS A RESULT...AND LEFT OUT
MENTION OF THUNDER.
REGARDING TEMPERATURES ON SATURDAY...BEHIND THIS SECONDARY TROUGH
AXIS...COOLER AIR...WITH 850 MB TEMPERATURES ON THE ORDER OF 3 TO 4
DEGREES CELSIUS WILL SLIDE SOUTH INTO THE OUTLOOK AREA.
THUS...COMBINED WITH MODEL GUIDANCE...CONTINUED WITH TEMPERATURES IN
THE LOWER 60S ACROSS THE NORTH TO NEAR 70 IN NORTH CENTRAL KANSAS
FOR SATURDAY. SATURDAY LOOKS TO BE SHAPING INTO A FAIRLY UNPLEASANT
DAY...WITH MOSTLY CLOUDY SKIES AND COOLER TEMPERATURES. TO ADD TO
THE MIX...STRONG NORTHWEST WINDS SUSTAINED NEAR 20 KTS CAN BE
EXPECTED...AND WITH SOME MIXING WILL LEAD TO GUSTS NEAR 30 KTS.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 319 PM CDT FRI MAY 31 2013
MAIN FORECAST CONCERNS WILL BE CHANCES FOR THUNDERSTORMS AND
TEMPERATURES.
AN UPPER LEVEL SHORT WAVE RIDGE WILL MOVE ACROSS THE AREA SATURDAY
NIGHT THROUGH SUNDAY NIGHT. DURING THIS TIME DRY CONDITIONS ARE
EXPECTED. A SURFACE HIGH WILL SETTLE INTO THE AREA SATURDAY NIGHT
AND KEEP WINDS LIGHT AND TEMPERATURES WILL DROP TO THE 40S. BY
SUNDAY THE SURFACE HIGH WILL MOVE OFF TO THE EAST. WINDS WILL TURN
TO THE SOUTH AND AS THE PRESSURE GRADIENT TIGHTENS...THE WINDS WILL
INCREASE DURING THE DAY ON SUNDAY. TEMPERATURES WILL BE WARMER FOR
SUNDAY AND SUNDAY NIGHT.
FOR MONDAY THROUGH FRIDAY ANOTHER UPPER LEVEL LOW WILL WORK ITS WAY
FROM THE PACIFIC NORTHWEST...THROUGH THE NORTHERN ROCKIES AND INTO
THE NORTHERN PLAINS. THIS IS A SIMILAR TRACK TO THE ONE FROM THE
PAST WEEK. BY MONDAY THE UPPER LOW STARTS TO SEND THE FIRST SHORT
WAVE INTO THE AREA AND BRINGS A CHANCE FOR THUNDERSTORMS. MODELS
BRING SEVERAL SHORT WAVES THROUGH THE AREA DURING THE WEEK. THERE
ARE SOME MINOR TIMING DIFFERENCES BETWEEN THE MODELS. THE CHANCE
FOR THUNDERSTORMS CONTINUES DURING THE WORK WEEK AS THE UPPER LOW
CONTINUES TO SEND SHORT WAVES INTO THE AREA. IT WILL NOT BE RAINING
ALL OF THE TIME AND THERE MAY BE TIMES WHERE SOME LOCATIONS DO NOT
HAVE ANY PRECIPITATION DURING SOME PERIODS... BUT THERE IS AT LEAST
A SMALL CHANCE EVERY DAY. THE BEST CHANCES SHOULD BE DURING THE
AFTERNOON AND INTO THE OVERNIGHT HOURS.
SOME OF THE STORMS COULD BE SEVERE DURING THIS PERIOD. THE BEST
CHANCE FOR SEVERE WILL BE TUESDAY AND TUESDAY NIGHT WHEN THE MUCAPE
APPROACHES 2500 J/KG. THERE COULD BE SOME ISOLATED SEVERE AT OTHER
TIMES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1242 PM CDT FRI MAY 31 2013
WHILE VFR CONDITIONS WILL CONTINUE THROUGHOUT MOST OF THE TAF
PERIOD...THERE IS AT LEAST SOME CONCERN FOR MVFR CEILINGS TOWARDS
THE END OF THE PERIOD. AN UPPER LEVEL LOW PRESSURE SYSTEM CENTERED
ACROSS THE DAKOTAS THIS MORNING WILL CONTINUE TO HAVE AN EFFECT ON
THE PLAINS THROUGHOUT THE PERIOD. LATEST SATELLITE IMAGERY
INDICATES A CUMULUS FIELD DEVELOPING ACROSS MOST OF THE
NORTHWESTERN HALF OF NEBRASKA. CURRENT THINKING IS THAT THESE
CLOUDS WILL BEGIN TO SHIFT THROUGH THE TAF SITE AFTER 0Z...WITH
LOWERING CLOUD BASES THEREAFTER. COMBINED WITH THESE CLOUDS...AN
ASSOCIATED TROUGH AXIS WILL ALSO PUSH THROUGH THE PLAINS ROUGHLY
AROUND 6Z...WHICH WILL HELP BRING A SLIGHT WIND SHIFT TO THE
NORTHWEST. LATEST MODEL TRENDS INDICATE AT LEAST SOME CHANCE THAT
SHOWERS ASSOCIATED WITH THIS TROUGH AXIS WILL BE OVER OR JUST
NORTH OF THE TAF SITE BY THE MORNING HOURS ON SATURDAY. THUS
CONTINUED WITH LIGHT RAIN SHOWER MENTION AFTER 10Z SATURDAY.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...SALTZMAN
LONG TERM...JCB
AVIATION...SALTZMAN
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1141 PM CDT THU MAY 30 2013
.AVIATION...06Z TAFS FOR KOFK...KLNK AND KOMA.
GENERALLY VFR CONDITIONS ARE EXPECTED THROUGH FRIDAY EVENING. A
LOW PRESSURE SYSTEM OVER THE NORTHERN PLAINS WILL BRING STRONG
SOUTHWEST TO WEST WINDS ACROSS EASTERN NEBRASKA TAF SITES FRIDAY
AFTERNOON. EXPECT WINDS OF 15 TO 30KT WITH SCATTERED TO BROKEN
CLOUDS AT FL040. THERE IS A SMALL CHANCE FOR SHOWERS BEFORE
BETWEEN 10Z AND 14Z...THEN ISOLATED THUNDERSTORMS BETWEEN 21Z AND
00Z. DID NOT INCLUDE THESE IN THE TAF AS COVERAGE IS EXPECTED TO
BE ISOLATED.
DERGAN
&&
.PREV DISCUSSION... /ISSUED 1004 PM CDT THU MAY 30 2013/
UPDATE...
CONVECTION IS FINALLY WINDING DOWN ACROSS EASTERN NEBRASKA AND
SOUTHWEST IOWA...WITH A FEW SHOWERS AND ISOLATED LIGHTNING STRIKES
OCCURRING IN PARTS OF NORTHEAST NEBRASKA AND IN AREAS EAST AND
NORTHEAST OF THE COUNCIL BLUFFS METRO AREA. EXPECT IOWA ACTIVITY
TO MOVE EAST OF OUR AREA WELL BEFORE MIDNIGHT...AND NORTHEAST
NEBRASKA ACTIVITY TO PERSIST FOR A COUPLE OF HOURS. AFTER
MIDNIGHT...SHORT RANGE HRRR AND RAP MODELS ARE BOTH SUGGESTING
SOME SHOWER DEVELOPMENT IN WESTERN NEBRASKA WILL SWING EAST
THROUGH EASTERN NEBRASKA AND SOUTHWEST IOWA. SOME INDICATION OF
THIS ACTIVITY FORMING NOW IN SOUTHWEST NEBRASKA...SO HAVE NO
REASON TO REMOVE THE CHANCE FOR MORE SHOWERS LATER TONIGHT AS PER
GOING FORECAST.
DERGAN
PREV DISCUSSION... /ISSUED 302 PM CDT THU MAY 30 2013/
DISCUSSION...
MAIN CONVECTIVE ACTIVITY HAS SHIFTED EAST OF THE AREA THIS
AFTERNOON WITH CLOSED UPPER LOW LOCATED OVER WESTERN SOUTH DAKOTA
AND SURFACE TROUGH JUST NOSING INTO EASTERN NEBRASKA.
ALTHOUGH THE CHANCE OF THUNDERSTORMS WILL REMAIN ACROSS THE AREA
TONIGHT AND FRIDAY...GENERAL TREND WILL BE TOWARD MORE STABLE
CONDITIONS BY LATE SATURDAY AND THROUGH THE REMAINDER OF THE
WEEKEND AS THE UPPER SYSTEM TRACKS TOWARD THE GREAT LAKES REGION
AND HIGH PRESSURE BUILDS INTO THE CENTRAL PLAINS. TEMPERATURES
WILL BE TURNING COOLER FOR THE WEEKEND AS A COLD FRONT MOVES
THROUGH THE REGION WITH CLOUDS AND SHOWERS ASSOCIATED WITH THE
UPPER LOW LIKELY TO KEEP HIGHS ONLY IN THE 60S FOR SATURDAY.
BREEZY CONDITIONS ALSO EXPECTED ON SATURDAY BEHIND THE FRONT AS
THE COOLER AIR MOVES INTO THE REGION. WARMER AIR RETURNS FOR
SUNDAY SURFACE HIGH SHIFTS EAST WITH CONSIDERABLE SUNSHINE
EXPECTED.
EXTENDED PERIOD LOOKS LIKE IT COULD TURN WET AGAIN AS THE
UPPER LEVEL PATTERN TAKES ON SIMILAR CHARACTERISTICS OF
THIS PAST WEEKS SYSTEM. ANOTHER CLOSED LOW MOVES INTO THE
NORTHERN ROCKIES BY MONDAY THEN TRACKS EAST ACROSS THE NORTHERN
PLAINS AND INTO THE UPPER MIDWEST BY THURSDAY. MODELS HOWEVER
DIFFER ON STRENGTH AND TIMING OF SHORT WAVES SO LIMITED CONFIDENCE
IN EITHER SOLUTION AT THIS TIME.
FOBERT
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BUFFALO NY
937 PM EDT SAT JUN 1 2013
.SYNOPSIS...
A COLD FRONT WILL GRADUALLY APPROACH FROM THE UPPER LAKES
TONIGHT...CROSSING THE REGION LATE ON SUNDAY. THIS WILL BRING AN
INCREASING CHANCE FOR SHOWERS AND THUNDERSTORMS TONIGHT INTO
SUNDAY...WITH LOCALLY HEAVY DOWNPOURS POSSIBLE. COOLER AND DRIER AIR
WILL BUILD INTO THE REGION FOR THE FIRST HALF OF THE WEEK.
&&
.NEAR TERM /THROUGH SUNDAY/...
SHOWERS AND THUNDERSTORMS EXTEND ALONG A BOUNDARY WHICH EXTENDS
FROM WESTERN PORTIONS OF THE SOUTHERN TIER TO EASTERN LAKE
ONTARIO. THIS LINE IS FORECAST TO CONTINUE TO SLIDE EASTWARD.
WITH THE LOSS OF DAYTIME HEATING AND FOLLOWING AN INITIAL ROUND
OF CONVECTION...THE CHANCE FOR WINDS TO MIX DOWN IS DIMINISHED
FROM EARLIER TODAY. WHILE STORMS STILL BEAR WATCHING...EXPECT THE
SEVERE WEATHER POTENTIAL TO DIMINISH THROUGH LATE EVENING.
FORECAST CONFIDENCE INCREASES LATER TONIGHT...DUE TO A STRONGER
MODEL CONSENSUS. WITH THE HRRR ALSO LENDING SUPPORT THE OTHER
GUIDANCE (NAM/RGEM/SREF/GFS)...THERE IS A HIGH CONFIDENCE IN
SHOWERS AND THUNDERSTORMS MOVING IN FROM WEST TO EAST LATE TONIGHT
AS AN UPPER TROF GETS CLOSER. A STRONG MODEL CONSENSUS SHOWS SOME
MEASURABLE QPF IN WESTERN SECTIONS BY DAYBREAK SUNDAY...AND GIVEN
THE SYNOPTIC FEATURE THIS MAKES SENSE. LATER TONIGHT...THERE IS A
POTENTIAL FOR HEAVY RAIN...WITH PWATS FORECAST TO INCREASE TO
1.75 INCHES BY BOTH THE NAM/GFS.
TEMPERATURES SHOULD ONLY DROP INTO THE UPPER 60S OVERNIGHT...AS
WINDS/CLOUDS AND RAIN LIMIT RADIATIONAL COOLING. HIGHS ON SUNDAY
SHOULD BE NOTABLY COOLER..RANGING FROM THE 70S IN WESTERN
SECTIONS TO LOWER 80S ACROSS THE GENESEE VALLEY AND FINGER LAKES REGIONS.
SHOWERS AND THUNDERSTORMS SHOULD TAPER OFF FROM WEST TO EAST ON
SUNDAY. THIS ACTIVITY IS LIKELY TO BE ALONG A PRE-FRONTAL
TROF...WITH THE ACTUAL FRONT AND WIND SHIFT LIKELY TO HOLD OFF UNTIL
LATER IN THE DAY. THIS MAY SPARK AN ADDITIONAL SHOWER...WITH A
SIGNIFICANT BREAK OF FAIR WEATHER POSSIBLE BETWEEN THE PRE-FRONTAL
TROF AND THE FRONT ITSELF.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
THE CLOSED UPPER LOW OVER ONTARIO PROVINCE BETWEEN THE NORTHERN
GREAT LAKES AND JAMES BAY WILL MOVE EAST SUNDAY NIGHT AS A
POSTFRONTAL SURFACE RIDGE BUILDS ACROSS NEW YORK STATE. THIS WILL
CLEAR OUT LOW LEVEL DEWPOINTS FROM THE UPPER 50S TO 60 DEGREES
SUNDAY EVENING...TO THE MID 40S TO LOW 50S BY DAYBREAK ON MONDAY.
THERE WILL ALSO BE A CLEARING TREND WITH THE INFLUX OF THE DRIER
AIRMASS AND COLD ADVECTION WILL BRING OVERNIGHT LOWS TO THE UPPER
40S TO LOW 50S.
SURFACE HIGH PRESSURE CENTER OVER SOUTHERN ONTARIO PROVINCE WILL
PROVIDE A DRY AND COOL PERIOD FOR THE FIRST HALF OF THE WEEK WITH
POPS NEAR ZERO AND ABUNDANT SUNSHINE. HIGH TEMPS WILL BE IN THE
LOWER TO MIDDLE 60S AT THE START OF THE WEEK AND NUDGE UP TO THE MID
AND UPPER 60S ON TUESDAY. DRY AIR AND CLEAR SKIES AT NIGHT WILL
ALLOW LOW TEMPS TO FALL TO THE LOWER TO MID 40S FOR MOST OF THE AREA
MONDAY NIGHT AND MOSTLY IN THE MID TO UPPER 40S FOR TUESDAY NIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
THE CENTER OF THE SURFACE HIGH ACROSS SOUTHERN ONTARIO WILL MOVE
EASTWARD AND ALLOW A SOUTHERLY FLOW ACROSS THE FORECAST AREA. THIS
WILL BRING A MIDWEEK WARMING TREND WITH HIGH TEMPS RETURNING TO NEAR
NORMAL READINGS IN THE LOWER TO MID 70S. OVERNIGHT LOWS WILL ALSO
MODERATE TO NEAR OR ABOVE NORMAL READINGS...RANGING FROM THE LOWER
TO MID 50S WEDNESDAY NIGHT TO THE MID AND UPPER 50S THURSDAY NIGHT
AND FRIDAY NIGHT.
THE RETURN OF WARMTH WILL ALSO BRING A RETURN OF HUMIDITY AND A FAIR
CHANCE OF RAIN FROM THURSDAY THROUGH SATURDAY. PRECIPITABLE WATER
VALUES WILL INCREASE FROM AROUND A HALF INCH AT MID WEEK TO MORE
THEN AN INCH AND A HALF BY THE END OF THE WEEK...THUS WE CAN EXPECT
THE POSSIBILITY OF DOWNPOURS ASSOCIATED WITH ANY CONVECTION.
&&
.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
OUTSIDE OF LOCALLY LOWER CONDITIONS IN SHOWERS AND THUNDERSTORMS
EXPECT PREDOMINANTLY VFR CONDITIONS TONIGHT. SHOWERS AND
THUNDERSTORMS SHOULD BECOME MORE WIDESPREAD LATE TONIGHT...AS AN
AREA OF ORGANIZED CONVECTION IS LIKELY TO TRACK FROM WEST TO EAST
LATE TONIGHT AND INTO SUNDAY MORNING. EXPECT THINGS TO CLEAR OUT
BEHIND THIS...WITH A RETURN TO VFR CONDITIONS. A COLD FRONT WILL
CROSS TOWARD 00Z...WITH WIND SHIFT AND PERHAPS A FEW SHOWERS.
OUTLOOK...
SUNDAY NIGHT...MAINLY VFR. A CHANCE OF SHOWERS.
MONDAY THROUGH WEDNESDAY...VFR.
THURSDAY...MAINLY VFR. A CHANCE OF THUNDERSTORMS.
&&
.MARINE...
AN AREA OF LOW PRESSURE WILL PASS BY TO THE NORTH OF THE REGION
SUNDAY WITH A COLD FRONT CROSSING THE LOWER LAKES. WINDS WILL
INCREASE OUT OF THE SOUTHWEST ALONG AND BEHIND THIS COLD FRONT
WITH THE POTENTIAL FOR A PERIOD OF WINDS AND WAVES APPROACHING
SMALL CRAFT ADVISORY CRITERIA.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL/LEVAN
SHORT TERM...WCH
LONG TERM...WCH
AVIATION...APFFEL/LEVAN
MARINE...APFFEL/WCH
AREA FORECAST DISCUSSION
NWS BUFFALO NY
815 PM EDT SAT JUN 1 2013
.SYNOPSIS...
A COLD FRONT WILL GRADUALLY APPROACH FROM THE UPPER LAKES
TONIGHT...CROSSING THE REGION LATE ON SUNDAY. THIS WILL BRING AN
INCREASING CHANCE FOR SHOWERS AND THUNDERSTORMS TONIGHT INTO
SUNDAY...WITH LOCALLY HEAVY DOWNPOURS POSSIBLE. COOLER AND DRIER AIR
WILL BUILD INTO THE REGION FOR THE FIRST HALF OF THE WEEK.
&&
.NEAR TERM /THROUGH SUNDAY/...
THROUGH THIS EVENING...SHOWERS AND THUNDERSTORMS EXTEND ALONG A
BOUNDARY WHICH EXTENDS FROM WESTERN PORTIONS OF THE SOUTHERN TIER
TO EASTERN LAKE ONTARIO. THIS LINE CAN BE SEEN ON IR SATELLITE
IMAGERY...AND IS FORECAST TO CONTINUE TO SLIDE EASTWARD. WIND
PROFILES SHOW A FAIR AMOUNT OF SHEAR...WITH 850 MB WINDS
INCREASING TO 40 KTS. STORMS HAVE DEVELOPED INTO LINEAR BOWING
SEGMENTS...A COUPLE STRONG INDIVIDUAL CELLS. WITH THE LOSS OF
DAYTIME HEATING AND FOLLOWING AN INITIAL ROUND OF CONVECTION...THE
CHANCE FOR WINDS TO MIX DOWN IS DIMINISHED FROM EARLIER TODAY.
WHILE STORMS STILL BEAR WATCHING...EXPECT THE SEVERE WEATHER
POTENTIAL TO DIMINISH THROUGH LATE EVENING.
FORECAST CONFIDENCE INCREASES LATER TONIGHT...DUE TO A STRONGER
MODEL CONSENSUS. WITH THE HRRR ALSO LENDING SUPPORT THE OTHER
GUIDANCE (NAM/RGEM/SREF/GFS)...THERE IS A HIGH CONFIDENCE IN
SHOWERS AND THUNDERSTORMS MOVING IN FROM WEST TO EAST LATE TONIGHT
AS AN UPPER TROF GETS CLOSER. A STRONG MODEL CONSENSUS SHOWS SOME
MEASURABLE QPF IN WESTERN SECTIONS BY DAYBREAK SUNDAY...AND GIVEN
THE SYNOPTIC FEATURE THIS MAKES SENSE. LATER TONIGHT...THERE IS A
POTENTIAL FOR HEAVY RAIN...WITH PWATS FORECAST TO INCREASE TO
1.75 INCHES BY BOTH THE NAM/GFS.
TEMPERATURES SHOULD ONLY DROP INTO THE UPPER 60S OVERNIGHT...AS
WINDS/CLOUDS AND RAIN LIMIT RADIATIONAL COOLING. HIGHS ON SUNDAY
SHOULD BE NOTABLY COOLER..RANGING FROM THE 70S IN WESTERN
SECTIONS TO LOWER 80S ACROSS THE GENESEE VALLEY AND FINGER LAKES REGIONS.
SHOWERS AND THUNDERSTORMS SHOULD TAPER OFF FROM WEST TO EAST ON
SUNDAY. THIS ACTIVITY IS LIKELY TO BE ALONG A PRE-FRONTAL
TROF...WITH THE ACTUAL FRONT AND WIND SHIFT LIKELY TO HOLD OFF UNTIL
LATER IN THE DAY. THIS MAY SPARK AN ADDITIONAL SHOWER...WITH A
SIGNIFICANT BREAK OF FAIR WEATHER POSSIBLE BETWEEN THE PRE-FRONTAL
TROF AND THE FRONT ITSELF.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
THE CLOSED UPPER LOW OVER ONTARIO PROVINCE BETWEEN THE NORTHERN
GREAT LAKES AND JAMES BAY WILL MOVE EAST SUNDAY NIGHT AS A
POSTFRONTAL SURFACE RIDGE BUILDS ACROSS NEW YORK STATE. THIS WILL
CLEAR OUT LOW LEVEL DEWPOINTS FROM THE UPPER 50S TO 60 DEGREES
SUNDAY EVENING...TO THE MID 40S TO LOW 50S BY DAYBREAK ON MONDAY.
THERE WILL ALSO BE A CLEARING TREND WITH THE INFLUX OF THE DRIER
AIRMASS AND COLD ADVECTION WILL BRING OVERNIGHT LOWS TO THE UPPER
40S TO LOW 50S.
SURFACE HIGH PRESSURE CENTER OVER SOUTHERN ONTARIO PROVINCE WILL
PROVIDE A DRY AND COOL PERIOD FOR THE FIRST HALF OF THE WEEK WITH
POPS NEAR ZERO AND ABUNDANT SUNSHINE. HIGH TEMPS WILL BE IN THE
LOWER TO MIDDLE 60S AT THE START OF THE WEEK AND NUDGE UP TO THE MID
AND UPPER 60S ON TUESDAY. DRY AIR AND CLEAR SKIES AT NIGHT WILL
ALLOW LOW TEMPS TO FALL TO THE LOWER TO MID 40S FOR MOST OF THE AREA
MONDAY NIGHT AND MOSTLY IN THE MID TO UPPER 40S FOR TUESDAY NIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
THE CENTER OF THE SURFACE HIGH ACROSS SOUTHERN ONTARIO WILL MOVE
EASTWARD AND ALLOW A SOUTHERLY FLOW ACROSS THE FORECAST AREA. THIS
WILL BRING A MIDWEEK WARMING TREND WITH HIGH TEMPS RETURNING TO NEAR
NORMAL READINGS IN THE LOWER TO MID 70S. OVERNIGHT LOWS WILL ALSO
MODERATE TO NEAR OR ABOVE NORMAL READINGS...RANGING FROM THE LOWER
TO MID 50S WEDNESDAY NIGHT TO THE MID AND UPPER 50S THURSDAY NIGHT
AND FRIDAY NIGHT.
THE RETURN OF WARMTH WILL ALSO BRING A RETURN OF HUMIDITY AND A FAIR
CHANCE OF RAIN FROM THURSDAY THROUGH SATURDAY. PRECIPITABLE WATER
VALUES WILL INCREASE FROM AROUND A HALF INCH AT MID WEEK TO MORE
THEN AN INCH AND A HALF BY THE END OF THE WEEK...THUS WE CAN EXPECT
THE POSSIBILITY OF DOWNPOURS ASSOCIATED WITH ANY CONVECTION.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
EXPECT THE MAJORITY OF THIS EVENING TO BE VFR...OUTSIDE OF LOCALLY
LOWER CONDITIONS IN SHOWERS AND THUNDERSTORMS. THESE SHOULD
INITIALLY TAPER OFF...BUT THEN BECOME MORE WIDESPREAD LATE
TONIGHT...AS AN AREA OF ORGANIZED CONVECTION IS LIKELY TO TRACK
FROM WEST TO EAST LATE TONIGHT AND INTO SUNDAY MORNING. EXPECT
THINGS TO CLEAR OUT BEHIND THIS...WITH A RETURN TO VFR CONDITIONS.
A COLD FRONT WILL CROSS TOWARD 00Z...WITH WIND SHIFT AND PERHAPS A
FEW SHOWERS.
OUTLOOK...
SUNDAY NIGHT...MAINLY VFR. A CHANCE OF SHOWERS.
MONDAY THROUGH WEDNESDAY...VFR.
THURSDAY...MAINLY VFR. A CHANCE OF THUNDERSTORMS.
&&
.MARINE...
AN AREA OF LOW PRESSURE WILL PASS BY TO THE NORTH OF THE REGION
SUNDAY WITH A COLD FRONT CROSSING THE LOWER LAKES. WINDS WILL
INCREASE OUT OF THE SOUTHWEST ALONG AND BEHIND THIS COLD FRONT
WITH THE POTENTIAL FOR A PERIOD OF WINDS AND WAVES APPROACHING
SMALL CRAFT ADVISORY CRITERIA.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL
SHORT TERM...WCH
LONG TERM...WCH
AVIATION...APFFEL
MARINE...APFFEL/WCH
AREA FORECAST DISCUSSION
NWS BUFFALO NY
515 PM EDT FRI MAY 31 2013
.SYNOPSIS...
A HOT AND HUMID AIRMASS WILL REMAIN IN PLACE THROUGH THE FIRST HALF
OF THE WEEKEND WITH AT LEAST SCATTERED SHOWERS THUNDERSTORMS TONIGHT
AND SATURDAY. THE HIGHEST THREAT FOR RAINFALL WILL BE LATER
SATURDAY NIGHT AND SUNDAY AS A COLD FRONT CROSSES THE REGION. THIS
FRONT WILL USHER IN A COOLER AND DRIER AIRMASS FOR THE FIRST HALF OF
NEXT WEEK.
&&
.NEAR TERM /THROUGH SATURDAY/...
AN UPPER LEVEL RIDGE IS OFF THE EAST COAST WITH MOISTURE BEING
ADVECTED ACROSS THE OHIO VALLEY TOWARD NY. SCATTERED CONVECTION
OVER CENTRAL OH MATCHES 00Z SSEO NICELY WHILE EACH CONSECUTIVE
RUN OF THE HRRR SEEMS TO BE MISSING THE LEADING LINE. SO BASED OFF
THE 00Z SSEO AND TO SOME EXTENT THE 12Z NAM...BUT PRIMARILY
SATELLITE/OBSERVATION EXTRAPOLATION...EXPECT A FAIRLY DISORGANIZED
LINE OF THUNDERSTORMS TO DEVELOP LATER THIS AFTERNOON AND WORK ITS
WAY INTO THE SOUTHERN TIER AND THEN NIAGARA FRONTIER EARLY THIS
EVENING...BEFORE WEAKENING OR COMPLETELY FALLING APART OVER THE
GENESEE VALLEY/FINGER LAKES REGION. THIS WILL LEAVE QUITE A BIT OF
CLOUD COVER OVER THE REGION...AND THUS EXPECT LOWS TO GET STUCK IN
THE UPPER 60S TO NEAR 70 FOR MOST LOCATIONS...A BIT ABOVE MOST
GUIDANCE.
EXTENSIVE CLOUD COVER WILL CONTINUE INTO SATURDAY IN THE MOIST AND
UNSTABLE ATMOSPHERE. THIS WILL LIMIT DAYTIME HIGHS FROM GETTING TOO
HIGH...WITH MOST AREAS IN THE LOW TO MID 80S. THE CLOUD COVER WILL
ALSO PREVENT WIDESPREAD CONVECTION. INSTEAD...EXPECT HIT/MISS
SHOWERS TO DEVELOP. INITIATION AND EVENTUAL LOCATION WILL BE NEARLY
IMPOSSIBLE TO PINPOINT AS BOTH LOCAL MESOSCALE BOUNDARIES /LAKE
BREEZES/ AND GENERAL SYNOPTIC SCALE LIFT MAY FORCE THUNDERSTORM
DEVELOPMENT. WILL SLOWLY INCREASE THE PROBABILITY OF PRECIPITATION
INTO THE AFTERNOON...WITH INCREASING PRECIPITABLE
WATER...INSTABILITY AND THE APPROACHING COLD FRONT CREATING A BETTER
CHANCE FOR CONVECTION WITH TIME.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
IT WILL BE A WARM AND HUMID NIGHT ON SATURDAY NIGHT WITH OVERNIGHT
LOW TEMPS IN THE UPPER 60S ACROSS THE HIGHLANDS OF THE SOUTHERN TIER
AND THE TUG HILL PLATEAU WITH LOWER 70S FOR THE LAKE PLAINS AND
URBAN AREAS. IT WILL ALSO BECOME RATHER BREEZY WITH THE TIGHTENING
PRESSURE GRADIENT AHEAD OF THE APPROACHING COLD FRONT...WHICH WILL
HELP TO HOLD THE TEMPS UP THROUGH THE NIGHT.
PRECIP WILL PRECEDE THE COLD FRONT WITH THE 40 KNOT 850MB JET
FEEDING THE CONVECTION AND PROVIDING LOW LEVEL CONVERGENCE.
PRECIPITABLE WATER VALUES INCREASE TO NEARLY ONE AND THREE QUARTERS
OF AN INCH WITH HIGH PRECIP EFFICIENCY AND INDICATIONS OF TRAINING
STORMS ALONG THE FRONT. WILL CARRY CATEGORICAL POPS SATURDAY NIGHT
THROUGH SUNDAY AS THE FRONT AND PRECEDENT PRECIP CROSS THE REGION.
TEMPS ON SUNDAY WILL BE IN THE MID 70S TO LOW 80S...LIMITED BY THE
PRECIP AND THE PASSAGE OF THE COLD FRONT. PRECIP SHOULD TAPER OFF
QUICKLY WITH THE FRONTAL PASSAGE WITH ONLY SCATTERED SHOWERS
TRAILING THE FRONT. SKIES WILL START TO CLEAR ON MONDAY AS HIGH
PRESSURE NOSES IN FROM THE WEST WITH MUCH COOLER TEMPS IN THE MID TO
UPPER 60S...THEN CLEARING AND VERY COOLER MONDAY NIGHT WITH LOWS IN
THE 40S.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
COOLER CANADIAN HIGH PRESSURE ACROSS SOUTHERN ONTARIO WILL RESULT IN
SUNNY SKIES AND COOLER THAN NORMAL TEMPERATURES...THE COOLEST TEMPS
ON TUESDAY THEN A WARMING TREND THROUGH THE WEEK. MEANWHILE...WE CAN
ANTICIPATE GENERALLY RAINFREE WEATHER FOR TUESDAY THROUGH WEDNESDAY
NIGHT. AN UPPER LOW PASSING EASTWARD ACROSS WESTERN ONTARIO WILL
BRING A CHANCE OF SHOWERS AND THUNDERSTORMS THURSDAY AND FRIDAY AS A
WARMER AND INCREASINGLY MORE HUMID SOUTHERLY FLOW DEVELOPS.
PRECIPITABLE WATER VALUES WILL INCREASE FROM AROUND A HALF INCH AT
MID WEEK TO MORE THEN AN INCH AND A HALF BY THE END OF THE WEEK.
TEMPS WILL CLIMB FROM THE 60S ON TUESDAY TO THE LOWER TO MID 70S ON
WEDNESDAY...AND THE MID 70S ON THURSDAY AND FRIDAY. OVERNIGHT LOW
TEMPS WILL ALSO RETURN TO A NEARLY NORMAL TREND WITH 40S TUESDAY
NIGHT TEMPERING TO THE LOWER TO MID 50S THURSDAY NIGHT...EVEN SOME
UPPER 50S POSSIBLE.
&&
.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
VFR CONDITIONS EXPECTED THROUGH 18Z SATURDAY...ALBEIT WITH A FEW
ROUNDS OF CONVECTION. THE FIRST WEAKLY ORGANIZED AREA LIFTING
ACROSS OHIO AND EXPECT IT TO WORK ITS WAY INTO WESTERN NY BEFORE
WEAKENING AND/OR FALLING APART OVERNIGHT AS IT MOVES INTO THE
FINGER LAKES/GENESEE VALLEY REGION. LOCAL MVFR IS POSSIBLE WITH
THIS...BUT FOR NOW WILL KEEP ALL TAFS VFR WITHOUT AN MENTION OF
TS. CONVECTION ON SATURDAY SHOULD IN GENERAL HOLD OFF UNTIL AFTER
18Z...ALTHOUGH SOME SHOWER DEVELOPMENT IS POSSIBLE OVER FAR
WESTERN NY BEFORE THAT TIME. MOST OF THE CONVECTION AND
PRECIPITATION IS EXPECTED LATE SATURDAY EVENING/OVERNIGHT AS A
COLD FRONT MOVES ACROSS THE REGION.
OUTLOOK...
SUNDAY...VFR MUCH OF THE TIME...BUT OCCASIONAL SHOWERS AND
THUNDERSTORMS WILL PRODUCE LOCAL MVFR/IFR AT TIMES.
MONDAY-WEDNESDAY...VFR.
&&
.MARINE...
RELATIVELY LIGHT WINDS WILL CONTINUE THROUGH SATURDAY AS A GENERAL
SOUTH TO SOUTHWEST FLOW REMAINS IN PLACE AROUND A BERMUDA HIGH
PARKED OFF THE SOUTHEAST COAST. STRONG DIFFERENTIAL HEATING AND
RELATIVELY LIGHT SYNOPTIC SCALE FLOW WILL ALLOW LOCAL LAKE BREEZES
TO DEVELOP SATURDAY AFTERNOON...MAINLY ON THE EAST HALF OF LAKE
ONTARIO WITH WINDS BECOMING LOCALLY ONSHORE.
AN AREA OF LOW PRESSURE WILL PASS BY TO THE NORTH OF THE REGION
SUNDAY WITH A COLD FRONT CROSSING THE LOWER LAKES. WINDS WILL
INCREASE OUT OF THE SOUTHWEST ALONG AND BEHIND THIS COLD FRONT...
WITH CONDITIONS REACHING SMALL CRAFT ADVISORY CRITERIA.
&&
.CLIMATE...
RECORD HIGH FOR WATERTOWN TIED TODAY. 88 DEGREES SET IN 2010.
E
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ZAFF
NEAR TERM...LEVAN/ZAFF
SHORT TERM...WCH
LONG TERM...WCH
AVIATION...LEVAN/ZAFF
MARINE...ZAFF
CLIMATE...HITCHCOCK
AREA FORECAST DISCUSSION
NWS BUFFALO NY
252 PM EDT FRI MAY 31 2013
.SYNOPSIS...
A HOT AND HUMID AIRMASS WILL REMAIN IN PLACE THROUGH THE FIRST HALF
OF THE WEEKEND WITH AT LEAST SCATTERED SHOWERS THUNDERSTORMS TONIGHT
AND SATURDAY. THE HIGHEST THREAT FOR RAINFALL WILL BE LATER
SATURDAY NIGHT AND SUNDAY AS A COLD FRONT CROSSES THE REGION. THIS
FRONT WILL USHER IN A COOLER AND DRIER AIRMASS FOR THE FIRST HALF OF
NEXT WEEK.
&&
.NEAR TERM /THROUGH SATURDAY/...
AN UPPER LEVEL RIDGE IS OFF THE EAST COAST THIS AFTERNOON WITH
MOISTURE BEING ADVECTED ACROSS THE OHIO VALLEY TOWARD NY. SCATTERED
CONVECTION FORMING OVER CENTRAL OH MATCHES 00Z SSEO NICELY WHILE
EACH CONSECUTIVE RUN OF THE HRRR SEEMS TO BE MISSING THE LEADING
LINE. SO BASED OFF THE 00Z SSEO AND TO SOME EXTENT THE 12Z
NAM...BUT PRIMARILY SATELLITE/OBSERVATION EXTRAPOLATION...EXPECT A
FAIRLY DISORGANIZED LINE OF THUNDERSTORMS TO DEVELOP LATER THIS
AFTERNOON AND WORK ITS WAY INTO THE SOUTHERN TIER AND THEN NIAGARA
FRONTIER EARLY THIS EVENING...BEFORE WEAKENING OR COMPLETELY FALLING
APART OVER THE GENESEE VALLEY/FINGER LAKES REGION. THIS WILL LEAVE
QUITE A BIT OF CLOUD COVER OVER THE REGION...AND THUS EXPECT LOWS TO
GET STUCK IN THE UPPER 60S TO NEAR 70 FOR MOST LOCATIONS...A BIT
ABOVE MOST GUIDANCE.
EXTENSIVE CLOUD COVER WILL CONTINUE INTO SATURDAY IN THE MOIST AND
UNSTABLE ATMOSPHERE. THIS WILL LIMIT DAYTIME HIGHS FROM GETTING TOO
HIGH...WITH MOST AREAS IN THE LOW TO MID 80S. THE CLOUD COVER WILL
ALSO PREVENT WIDESPREAD CONVECTION. INSTEAD...EXPECT HIT/MISS
SHOWERS TO DEVELOP. INITIATION AND EVENTUAL LOCATION WILL BE NEARLY
IMPOSSIBLE TO PINPOINT AS BOTH LOCAL MESOSCALE BOUNDARIES /LAKE
BREEZES/ AND GENERAL SYNOPTIC SCALE LIFT MAY FORCE THUNDERSTORM
DEVELOPMENT. WILL SLOWLY INCREASE THE PROBABILITY OF PRECIPITATION
INTO THE AFTERNOON...WITH INCREASING PRECIPITABLE
WATER...INSTABILITY AND THE APPROACHING COLD FRONT CREATING A BETTER
CHANCE FOR CONVECTION WITH TIME.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
IT WILL BE A WARM AND HUMID NIGHT ON SATURDAY NIGHT WITH OVERNIGHT
LOW TEMPS IN THE UPPER 60S ACROSS THE HIGHLANDS OF THE SOUTHERN TIER
AND THE TUG HILL PLATEAU WITH LOWER 70S FOR THE LAKE PLAINS AND
URBAN AREAS. IT WILL ALSO BECOME RATHER BREEZY WITH THE TIGHTENING
PRESSURE GRADIENT AHEAD OF THE APPROACHING COLD FRONT...WHICH WILL
HELP TO HOLD THE TEMPS UP THROUGH THE NIGHT.
PRECIP WILL PRECEDE THE COLD FRONT WITH THE 40 KNOT 850MB JET
FEEDING THE CONVECTION AND PROVIDING LOW LEVEL CONVERGENCE.
PRECIPITABLE WATER VALUES INCREASE TO NEARLY ONE AND THREE QUARTERS
OF AN INCH WITH HIGH PRECIP EFFICIENCY AND INDICATIONS OF TRAINING
STORMS ALONG THE FRONT. WILL CARRY CATEGORICAL POPS SATURDAY NIGHT
THROUGH SUNDAY AS THE FRONT AND PRECEDENT PRECIP CROSS THE REGION.
TEMPS ON SUNDAY WILL BE IN THE MID 70S TO LOW 80S...LIMITED BY THE
PRECIP AND THE PASSAGE OF THE COLD FRONT. PRECIP SHOULD TAPER OFF
QUICKLY WITH THE FRONTAL PASSAGE WITH ONLY SCATTERED SHOWERS
TRAILING THE FRONT. SKIES WILL START TO CLEAR ON MONDAY AS HIGH
PRESSURE NOSES IN FROM THE WEST WITH MUCH COOLER TEMPS IN THE MID TO
UPPER 60S...THEN CLEARING AND VERY COOLER MONDAY NIGHT WITH LOWS IN
THE 40S.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
COOLER CANADIAN HIGH PRESSURE ACROSS SOUTHERN ONTARIO WILL RESULT IN
SUNNY SKIES AND COOLER THAN NORMAL TEMPERATURES...THE COOLEST TEMPS
ON TUESDAY THEN A WARMING TREND THROUGH THE WEEK. MEANWHILE...WE CAN
ANTICIPATE GENERALLY RAINFREE WEATHER FOR TUESDAY THROUGH WEDNESDAY
NIGHT. AN UPPER LOW PASSING EASTWARD ACROSS WESTERN ONTARIO WILL
BRING A CHANCE OF SHOWERS AND THUNDERSTORMS THURSDAY AND FRIDAY AS A
WARMER AND INCREASINGLY MORE HUMID SOUTHERLY FLOW DEVELOPS.
PRECIPITABLE WATER VALUES WILL INCREASE FROM AROUND A HALF INCH AT
MID WEEK TO MORE THEN AN INCH AND A HALF BY THE END OF THE WEEK.
TEMPS WILL CLIMB FROM THE 60S ON TUESDAY TO THE LOWER TO MID 70S ON
WEDNESDAY...AND THE MID 70S ON THURSDAY AND FRIDAY. OVERNIGHT LOW
TEMPS WILL ALSO RETURN TO A NEARLY NORMAL TREND WITH 40S TUESDAY
NIGHT TEMPERING TO THE LOWER TO MID 50S THURSDAY NIGHT...EVEN SOME
UPPER 50S POSSIBLE.
&&
.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
VFR CONDITIONS EXPECTED THROUGH 18Z SATURDAY...ALBEIT WITH A FEW
ROUNDS OF CONVECTION. THE FIRST WEAKLY ORGANIZED AREA IS FORMING
OVER OH...AND EXPECT IT TO WORK ITS WAY INTO WESTERN NY BEFORE
WEAKENING AND/OR FALLING APART OVERNIGHT AS IT MOVES INTO THE FINGER
LAKES/GENESEE VALLEY REGION. LOCAL MVFR IS POSSIBLE WITH
THIS...BUT FOR NOW WILL KEEP ALL TAFS VFR WITHOUT AN MENTION OF TS.
CONVECTION ON SATURDAY SHOULD IN GENERAL HOLD OFF UNTIL AFTER
18Z...ALTHOUGH SOME SHOWER DEVELOPMENT IS POSSIBLE OVER FAR WESTERN
NY BEFORE THAT TIME. MOST OF THE CONVECTION AND PRECIPITATION IS
EXPECTED LATE SATURDAY EVENING/OVERNIGHT AS A COLD FRONT MOVES
ACROSS THE REGION.
OUTLOOK...
SUNDAY...VFR MUCH OF THE TIME...BUT OCCASIONAL SHOWERS AND
THUNDERSTORMS WILL PRODUCE LOCAL MVFR/IFR AT TIMES.
MONDAY-WEDNESDAY...VFR.
&&
.MARINE...
RELATIVELY LIGHT WINDS WILL CONTINUE THROUGH SATURDAY AS A GENERAL
SOUTH TO SOUTHWEST FLOW REMAINS IN PLACE AROUND A BERMUDA HIGH
PARKED OFF THE SOUTHEAST COAST. STRONG DIFFERENTIAL HEATING AND
RELATIVELY LIGHT SYNOPTIC SCALE FLOW WILL ALLOW LOCAL LAKE BREEZES
TO DEVELOP SATURDAY AFTERNOON...MAINLY ON THE EAST HALF OF LAKE
ONTARIO WITH WINDS BECOMING LOCALLY ONSHORE.
AN AREA OF LOW PRESSURE WILL PASS BY TO THE NORTH OF THE REGION
SUNDAY WITH A COLD FRONT CROSSING THE LOWER LAKES. WINDS WILL
INCREASE OUT OF THE SOUTHWEST ALONG AND BEHIND THIS COLD FRONT...
WITH CONDITIONS REACHING SMALL CRAFT ADVISORY CRITERIA.
&&
.CLIMATE...
EARLY SEASON HEAT WILL CONTINUE TODAY. RECORD HIGHS FOR MAY 31 ARE
90 AT BUFFALO SET IN 1919...91 IN ROCHESTER SET IN 2011...AND 88
IN WATERTOWN SET IN 2010. AT BUFFALO...A SOUTHWEST FLOW OFF LAKE
ERIE WILL KEEP TEMPS WELL SHY OF THE RECORD. BOTH ROCHESTER AND
WATERTOWN WILL GET VERY CLOSE...WITH CURRENT FORECAST HIGHS WITHIN
A DEGREE OR SO OF THE RECORDS.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...HITCHCOCK/ZAFF
NEAR TERM...ZAFF
SHORT TERM...WCH
LONG TERM...WCH
AVIATION...ZAFF
MARINE...HITCHCOCK/ZAFF
CLIMATE...HITCHCOCK
AREA FORECAST DISCUSSION
NWS BUFFALO NY
200 PM EDT FRI MAY 31 2013
.SYNOPSIS...
A HOT AND HUMID AIRMASS WILL REMAIN IN PLACE THROUGH THE FIRST HALF
OF THE WEEKEND WITH AT LEAST SCATTERED SHOWERS THUNDERSTORMS TONIGHT
AND SATURDAY. THE HIGHEST THREAT FOR RAINFALL WILL BE LATER
SATURDAY NIGHT AND SUNDAY AS A COLD FRONT CROSSES THE REGION. THIS
FRONT WILL USHER IN A COOLER AND DRIER AIRMASS FOR THE FIRST HALF OF
NEXT WEEK.
&&
.NEAR TERM /THROUGH SATURDAY/...
AN UPPER LEVEL RIDGE IS OFF THE EAST COAST THIS AFTERNOON WITH
MOISTURE BEING ADVECTED ACROSS THE OHIO VALLEY TOWARD NY. SCATTERED
CONVECTION FORMING OVER CENTRAL OH MATCHES 00Z SSEO NICELY WHILE
EACH CONSECUTIVE RUN OF THE HRRR SEEMS TO BE MISSING THE LEADING
LINE. SO BASED OFF THE 00Z SSEO AND TO SOME EXTENT THE 12Z
NAM...BUT PRIMARILY SATELLITE/OBSERVATION EXTRAPOLATION...EXPECT A
FAIRLY DISORGANIZED LINE OF THUNDERSTORMS TO DEVELOP LATER THIS
AFTERNOON AND WORK ITS WAY INTO THE SOUTHERN TIER AND THEN NIAGARA
FRONTIER EARLY THIS EVENING...BEFORE WEAKENING OR COMPLETELY FALLING
APART OVER THE GENESEE VALLEY/FINGER LAKES REGION. THIS WILL LEAVE
QUITE A BIT OF CLOUD COVER OVER THE REGION...AND THUS EXPECT LOWS TO
GET STUCK IN THE UPPER 60S TO NEAR 70 FOR MOST LOCATIONS...A BIT
ABOVE MOST GUIDANCE.
EXTENSIVE CLOUD COVER WILL CONTINUE INTO SATURDAY IN THE MOIST AND
UNSTABLE ATMOSPHERE. THIS WILL LIMIT DAYTIME HIGHS FROM GETTING TOO
HIGH...WITH MOST AREAS IN THE LOW TO MID 80S. THE CLOUD COVER WILL
ALSO PREVENT WIDESPREAD CONVECTION. INSTEAD...EXPECT HIT/MISS
SHOWERS TO DEVELOP. INITIATION AND EVENTUAL LOCATION WILL BE NEARLY
IMPOSSIBLE TO PINPOINT AS BOTH LOCAL MESOSCALE BOUNDARIES /LAKE
BREEZES/ AND GENERAL SYNOPTIC SCALE LIFT MAY FORCE THUNDERSTORM
DEVELOPMENT. WILL SLOWLY INCREASE THE PROBABILITY OF PRECIPITATION
INTO THE AFTERNOON...WITH INCREASING PRECIPITABLE
WATER...INSTABILITY AND THE APPROACHING COLD FRONT CREATING A BETTER
CHANCE FOR CONVECTION WITH TIME.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
VERY WARM AND SOMEWHAT HUMID CONDITIONS WILL PREVAIL ON SATURDAY AS
THE DEEP LAYERED SOUTHWEST FLOW AROUND THE BERMUDA HIGH REMAINS IN
CONTROL. HOWEVER...THERE WILL BE A BETTER CHANCE FOR SOME CONVECTION
AS THE APPROACHING UPPER MIDWEST TROUGH BEGINS TO ERODE THE EASTERN
UPPER LEVEL RIDGE AND ALLOWS SOME OF THE UPSTREAM CONVECTION TO
ADVECT EAST ACROSS OUR CWA. IN ADDITION...OUR AREA WILL COME UNDER
THE INFLUENCE OF ADDITIONAL LIFT FROM A JET STREAK THAT WILL BE
ARCING FROM THE CENTRAL GREAT LAKES TO SOUTHERN QUEBEC. WILL
MAINTAIN CHANCE POPS FOR MEASURABLE PCPN SINCE THE BEST DYNAMICS
ASSOCIATED WITH THE UPPER TROUGH AND LOW LEVEL MOISTURE CONVERGENCE
ARE FORECAST TO STAY TO OUR WEST. RIGHT NOW IT LOOKS LIKE MOST
CONVECTION WILL STAY BELOW SEVERE LEVELS WITH INCREASING CLOUD COVER
EXPECTED TO LIMIT INSTABILITY.
THE AFOREMENTIONED UPPER LEVEL JET DYNAMICS WILL REMAIN IN PLACE
SATURDAY NIGHT...WHILE A 50 KNOT LOW LEVEL JET HEADS EAST INTO
WESTERN NEW YORK IN ADVANCE OF THE COLD FRONT THAT WILL BE WORKING
EAST TOWARD THE LOWER GREAT LAKES. THE IMPROVING LARGE SCALE LIFT
WILL SUPPORT MORE WIDESPREAD SHOWERS AND THUNDERSTORMS...
...PARTICULARLY OVER OUR WESTERN COUNTIES. FORECAST PWAT VALUES IN
EXCESS OF 1.5 INCHES WILL LEAD TO A HIGHER POTENTIAL FOR LOCALLY
HEAVY RAIN IN ANY CONVECTION. THE DEEP SOUTHERLY FLOW AHEAD OF THE
FRONT WILL MAKE THIS THE WARMEST NIGHT WITH MANY LOCATIONS ALONG THE
LAKE PLAINS STRUGGLING TO DROP BELOW 70 DEGREES.
THE SURFACE LOW THAT IS ASSOCIATED WITH THE APPROACHING UPPER LEVEL
TROUGH WILL TRACK NORTH OF NEW YORK STATE ON SUNDAY AND SWEEP THE
FIRST OF TWO COLD FRONTS ACROSS THE WESTERN COUNTIES DURING THE
MORNING...AND ACROSS THE EASTERN LAKE ONTARIO REGION DURING THE
MIDDAY. THIS TIMING OF THE FRONTAL PASSAGE WILL SHORTEN THE DURATION
OF WIDESPREAD PCPN...WHILE LIKELY REDUCING THE THREAT FOR SEVERE
CONVECTION. HOWEVER...PWAT VALUES >1.5 INCHES SHOULD STILL PROMOTE
HEAVY RAINS THROUGH MIDDAY. A DRY SLOT WILL WORK IN BEHIND THE COLD
FRONT...HELPING TO REDUCE THE POPS TO LOW CHANCE. TEMPERATURES
SUNDAY AFTERNOON WILL GENERALLY BE IN THE 70S.
WHEN THE SECONDARY COLD FRONT CROSSES WESTERN AND CENTRAL NEW YORK
SUNDAY EVENING...THE DEEPEST MOISTURE ASSOCIATED WITH THE FIRST
FRONT WILL HAVE MOVED EAST OF OUR AREA. AS A RESULT...EXPECT MAINLY
DRY CONDITIONS TO PREVAIL WITH THIS FRONT. OF GREATER NOTE...IT WILL
TURN COOLER AND LESS HUMID WITH EARLY MORNING TEMPERATURES COOLING
INTO THE LOWER TO MID 50S...RIGHT WHERE THEY SHOULD BE AT THIS POINT
IN THE SEASON.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
A LOW AMPLITUDE FLOW ACROSS THE COUNTRY DURING THIS PERIOD WILL
RESULT IN NEAR TO BELOW NORMAL TEMPERATURES...WITH THE COOLEST
CONDITIONS COMING AT THE START OF THE NEW WORK WEEK. MEANWHILE...WE
CAN ANTICIPATE GENERALLY RAINFREE WEATHER.
THE BASE OF A DIGGING H5 TROUGH WILL SWING ACROSS TO THE NORTH OF LK
ONTARIO ON MONDAY. LOW LEVEL RIDGING AND A WEALTH OF DRY AIR UNDER
THIS APPROACHING TROUGH SHOULD DISCOURAGE ANY PCPN...BUT WILL KEEP
SLGT CHC POPS IN PLACE ACROSS THE NORTH COUNTRY WHERE HGT FALLS WILL
BE THE MOST SIGNIFICANT. OUTSIDE OF THIS LONE `FLY IN THE
OINTMENT`...MONDAY SHOULD BE PARTLY TO MOSTLY SUNNY AND SEASONABLY
COOL WITH AFTERNOON TEMPERATURES IN THE 60S.
HIGH PRESSURE CENTERED OVER JAMES BAY WILL THEN NOSE SOUTH ACROSS
THE LOWER GREAT LAKES MONDAY NIGHT THROUGH WEDNESDAY...WITH H85
TEMPS GENERALLY IN THE UPPER SINGLE DIGITS. THIS WILL KEEP
PLEASANTLY COOL CONDITIONS IN PLACE A BIT LONGER...BUT TEMPERATURES
WILL MODERATE DURING THE SECOND HALF OF THE WEEK.
THE AFOREMENTIONED SFC HIGH WILL MOVE TO THE CANADIAN MARITIMES
WEDNESDAY NIGHT AND THURSDAY WHILE A SHORTWAVE WILL DIG ACROSS THE
NORTHERN PLAINS. THIS WILL SET UP A SOUTH TO SOUTHEAST FLOW OF
MILDER AIR ACROSS OUR REGION...PROMOTING MILDER WEATHER WITH DAYTIME
HIGHS CLIMBING BACK ABOVE NORMAL.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
VFR CONDITIONS EXPECTED THROUGH 18Z SATURDAY...ALBEIT WITH A FEW
ROUNDS OF CONVECTION. THE FIRST WEAKLY ORGANIZED AREA IS FORMING
OVER OH...AND EXPECT IT TO WORK ITS WAY INTO WESTERN NY BEFORE
WEAKENING AND/OR FALLING APART OVERNIGHT AS IT MOVES INTO THE FINGER
LAKES/GENESEE VALLEY REGION. LOCAL MVFR IS POSSIBLE WITH
THIS...BUT FOR NOW WILL KEEP ALL TAFS VFR WITHOUT AN MENTION OF TS.
CONVECTION ON SATURDAY SHOULD IN GENERAL HOLD OFF UNTIL AFTER
18Z...ALTHOUGH SOME SHOWER DEVELOPMENT IS POSSIBLE OVER FAR WESTERN
NY BEFORE THAT TIME. MOST OF THE CONVECTION AND PRECIPITATION IS
EXPECTED LATE SATURDAY EVENING/OVERNIGHT AS A COLD FRONT MOVES
ACROSS THE REGION.
OUTLOOK...
SUNDAY...VFR MUCH OF THE TIME...BUT OCCASIONAL SHOWERS AND
THUNDERSTORMS WILL PRODUCE LOCAL MVFR/IFR AT TIMES.
MONDAY-WEDNESDAY...VFR.
&&
.MARINE...
RELATIVELY LIGHT WINDS WILL CONTINUE THROUGH SATURDAY AS A GENERAL
SOUTH TO SOUTHWEST FLOW REMAINS IN PLACE AROUND A BERMUDA HIGH
PARKED OFF THE SOUTHEAST COAST. STRONG DIFFERENTIAL HEATING AND
RELATIVELY LIGHT SYNOPTIC SCALE FLOW WILL ALLOW LOCAL LAKE BREEZES
TO DEVELOP SATURDAY AFTERNOON...MAINLY ON THE EAST HALF OF LAKE
ONTARIO WITH WINDS BECOMING LOCALLY ONSHORE.
AN AREA OF LOW PRESSURE WILL PASS BY TO THE NORTH OF THE REGION
SUNDAY WITH A COLD FRONT CROSSING THE LOWER LAKES. WINDS WILL
INCREASE OUT OF THE SOUTHWEST ALONG AND BEHIND THIS COLD FRONT...
WITH CONDITIONS REACHING SMALL CRAFT ADVISORY CRITERIA.
&&
.CLIMATE...
EARLY SEASON HEAT WILL CONTINUE TODAY. RECORD HIGHS FOR MAY 31 ARE
90 AT BUFFALO SET IN 1919...91 IN ROCHESTER SET IN 2011...AND 88
IN WATERTOWN SET IN 2010. AT BUFFALO...A SOUTHWEST FLOW OFF LAKE
ERIE WILL KEEP TEMPS WELL SHY OF THE RECORD. BOTH ROCHESTER AND
WATERTOWN WILL GET VERY CLOSE...WITH CURRENT FORECAST HIGHS WITHIN
A DEGREE OR SO OF THE RECORDS.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...HITCHCOCK/ZAFF
NEAR TERM...ZAFF
SHORT TERM...TJP
LONG TERM...TJP
AVIATION...ZAFF
MARINE...HITCHCOCK/ZAFF
CLIMATE...HITCHCOCK
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
305 PM EDT FRI MAY 31 2013
.SYNOPSIS...
BERMUDA HIGH PRESSURE WILL CONTINUE ACROSS THE CAROLINAS THROUGH THE
WEEKEND. A COLD FRONT WILL SLOWLY MOVE THROUGH THE AREA EARLY NEXT
WEEK...BRINGING THE HIGHEST POTENTIAL FOR SHOWERS AND THUNDERSTORMS
MONDAY AND TUESDAY. HIGH PRESSURE WILL SLOWLY BUILD SOUTHWARD AND
INTO THE AREA DURING THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM FRIDAY...BERMUDA HIGH PRESSURE WELL OFFSHORE EXTENDS
INTO THE EASTERN CAROLINAS FROM A CENTER OVER 1000 MILES OFFSHORE. A
LONG EASTERLY FETCH ACROSS THE CENTRAL ATLANTIC OCEAN IS BRINGING
WARM AND HUMID AIR ONSHORE. SHOWERS HAVE BEEN MUCH MORE WIDESPREAD
TODAY THAN YESTERDAY MAINLY DUE TO RICHER BOUNDARY LAYER MOISTURE
EXISTING WITHIN AN UNCAPPED AND UNSTABLE ATMOSPHERE. THIS CONVECTIVE
ACTIVITY IS TIED TO DAYTIME HEATING AND SHOULD QUICKLY DIMINISH THIS
EVENING WITH MAINLY CLEAR SKIES DEVELOPING BY 8-10 PM.
MUCH LIKE LAST NIGHT...HIGH DEWPOINTS WITHIN THE BOUNDARY LAYER AND
LIGHT SURFACE WINDS SHOULD ALLOW LOW STRATUS AND FOG TO DEVELOP LATE
TONIGHT...MAINLY ACROSS THE SAME AREAS AS LAST NIGHT. OVERNIGHT LOWS
SHOULD RUN NEAR TO PERHAPS TWO DEGREES WARMER THAN LAST NIGHT...
GENERALLY MID 60S MOST AREAS TO AROUND 70 ON THE BEACHES.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 3 PM FRIDAY...HIGH PRESSURE WILL HOLD ON THROUGH THE
WEEKEND AS IT SLOWLY SLIPS FARTHER EAST. THE STRONG RIDGE OF HIGH
PRESSURE ALOFT WILL ALSO CONTINUE TO SHIFT EAST INTO THE ATLANTIC
WHILE A DEEPENING TROUGH MOVES IN FROM THE CENTRAL CONUS. THIS
TROUGH WILL PUSH A COLD FRONT EAST BUT WILL NOT REACH THE
CAROLINAS UNTIL MONDAY MORNING. AS THE RIDGE SLIPS EAST WE WILL
LOSE SOME OF OUR CAP ON CONVECTION AND SEE LOCALIZED SHWRS/TSTMS
THROUGH THE WEEKEND. BY SUNDAY THE WINDS WILL BE INCREASING OUT OF
THE SOUTH WHICH SHOULD PUSH SHWR DEVELOPMENT FARTHER WEST AND MAY
SEE FEWER SHOWERS OVER LOCAL CWA THROUGH THE AFTN. OVERALL EXPECT
A WARM AND HUMID SUMMER-LIKE AIR MASS TO REMAIN OVER THE AREA
THROUGH MUCH OF THE WEEKEND. SOUTHERLY WINDS WILL PICK UP
PRODUCING BREEZY WEATHER BY SUNDAY AFTERNOON. EXPECT CU TO BUILD
EACH AFTERNOON WITH BEST CONVERGENCE AND CHC OF CONVECTION ALONG
SEA BREEZE BOUNDARY AS IT PUSHES INLAND.
A DEEPER MOISTER SOUTHERLY FLOW WILL INCREASE THE OVERALL MOISTURE
THROUGH THE COLUMN BY THE END OF THE WEEKEND. PCP WATER VALUES
WILL REACH UP TO 1.5 INCHES INLAND EACH AFTERNOON AS SHWRS/TSTMS
FLARE UP BUT HEADING INTO LATE SUNDAY INTO SUNDAY NIGHT AHEAD OF
COLD FRONT...VALUES WILL REACH UP CLOSER TO 2 INCHES. CLOUDS WILL
INCREASE WITH SHOWERS AND THUNDERSTORMS INCREASING IN COVERAGE
SUNDAY NIGHT INTO MONDAY AS COLD FRONT APPROACHES FROM THE WEST.
THE WARM AND MOIST AIR MASS WILL CREATE MUCH LESS VARIATION IN DIURNAL
TEMPERATURE SWINGS. OVERNIGHT LOWS WILL ONLY DROP TO THE MID 60S
INLAND AND CLOSER TO 70 ALONG THE COAST. DAY TIME HIGHS WILL REACH
THE MID TO UPPER 80S...EXCEPT COOLER ALONG THE BEACHES.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 300 PM FRIDAY...WHAT WILL LIKELY BEGIN AS A VERY WET START TO
THE PERIOD WILL TRANSITION TO DRIER AND SEASONABLE CONDITIONS
THROUGH MUCH OF THE UPCOMING WEEK. THERE IS QUITE A BIT OF
UNCERTAINTY AT THE TAIL END OF THE PERIOD DUE TO INCREASED MOISTURE
ASSOCIATED WITH A POTENTIAL TROPICAL SYSTEM IN THE GOM.
BERMUDA HIGH PRESSURE WHICH HAS DOMINATED THE SYNOPTIC REGIME FOR
MORE THAN WEEK NOW WILL FINALLY BE DISPLACED BY EARLY TUESDAY THANKS
TO A COLD FRONT MOVING SLOWLY ACROSS THE SOUTHEAST. AHEAD OF THIS
BOUNDARY...PWATS RISE TO NEARLY 2 INCHES...WHICH IS APPROACHING +2SD
AND THE 99TH PERCENTILE FOR THE FIRST WEEK OF JUNE! THIS INCREDIBLY
MOIST ENVIRONMENT PAIRED WITH CONVERGENCE ALONG THE FRONT...SOME
DIFFLUENCE...ALBEIT RELATIVELY WEAK...WITHIN THE RIGHT ENTRANCE
REGION OF A 300MB JET STREAK...AND STRONG THETA-E RIDGING AHEAD OF
THE FRONT WILL SUPPORT WIDESPREAD SHOWERS WITH TSTMS ON MONDAY...AND
HAVE BUMPED POP TO LIKELY CWA-WIDE. THE HIGHEST POP IS EXPECTED LATE
MONDAY/MONDAY NIGHT.
FRONT MAY TAKE A WHILE TO CROSS THE AREA...AND THUS LOW-CHC POP IS
STILL WARRANTED INTO TUESDAY MORNING BEFORE SIGNIFICANT DRYING
OCCURS WITHIN THE COLUMN THANKS TO HIGH PRESSURE BUILDING DOWN FROM
THE NORTH. THIS WILL CREATE SEVERAL DAYS OF SEASONABLE EARLY-JUNE
WEATHER. LATE IN THE WEEK...HIGH PRESSURE SHIFTS OFFSHORE PUMPING
ATLANTIC MOISTURE BACK INTO THE AREA...AND DIURNAL CONVECTION WILL
BECOME INCREASINGLY LIKELY AGAIN. ADDITIONALLY...WHILE THE FAVORED
ECMWF KEEPS ANY TROPICAL MOISTURE WELL SW OF THE CAROLINAS...GFS
DOES SUGGEST SIGNIFICANT RAIN CHANCES BEGINNING FRIDAY AS MOISTURE
STREAMS OUT OF THE GOM. FOR NOW WILL LEAN HEAVILY ON THE ECMWF BUT
NOTE THAT MONITORING GUIDANCE EVOLUTION WILL BE IMPORTANT LEADING
INTO NEXT WEEKEND.
&&
.AVIATION /18Z FRIDAY THROUGH TUESDAY/...
AS OF 18Z...RADAR IMAGERY SHOWS SCATTERED SHOWERS/T-STORMS
DEVELOPING ALONG THE SEA BREEZE BOUNDARY THIS AFTN. HAVE INCLUDED
VCSH FOR KFLO/KLBT AS LATEST HRRR RUNS SHOW MORE SHOWERS DEVELOPING
INLAND LATER TODAY. OTHERWISE...VFR SHOULD PREVAIL WITH SCT/BKN CU
AND SSE WINDS AOB 10 KTS. MOSTLY CLEAR CONDITIONS TONIGHT AND PLENTY
OF LOW-LEVEL MOISTURE INDICATES FOG/STRATUS IS AGAIN LIKELY AFTER
06Z. SREF PROBS AND GUIDANCE SUGGEST IFR CIGS/VSBYS WILL BE MORE
WIDESPREAD INLAND...SIMILAR TO WHAT OCCURRED THIS MORNING. TEMPO IFR
IS ALSO QUITE POSSIBLE ALONG THE COAST...MOST LIKELY IN THE 09-12Z
RANGE. FOG/STRATUS SHOULD LIFT SOON AFTER 12Z SATURDAY.
EXTENDED OUTLOOK...EARLY MORNING MVFR/IFR CIGS/VSBYS POSSIBLE
THROUGH SUNDAY. SLIGHT CHANCE OF SHOWERS INLAND ON SUNDAY...WITH
BETTER PCPN CHANCES ACROSS THE CWA MONDAY AND TUESDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM FRIDAY...BERMUDA HIGH PRESSURE CONTINUES TO EXTEND A
RIDGE AXIS WESTWARD ACROSS THE CAROLINAS AT NEARLY THE SAME LATITUDE
AS LAST NIGHT. THEREFORE IT SHOULD NOT BE SURPRISING THE ANTICIPATED
WIND DIRECTION AND SPEED TONIGHT IS VERY SIMILAR TO LAST NIGHT.
SOUTH WINDS 5-10 KNOTS SHOULD PREVAIL THROUGH THE NIGHT AFTER THIS
AFTERNOON`S SEA BREEZE CIRCULATION DIES DOWN BY 9-10 PM. SEAS ARE
AVERAGING 3 FEET ON THE BUOYS NEAR CAPE FEAR WITH A DOMINANT PERIOD
AROUND 8 SECONDS. THIS IS VERY WELL MODELED IN THE NOAA WAVEWATCH
MODEL WHICH SHOWS THIS SOUTHEAST SWELL CONTINUING UNCHANGED THROUGH
THE NIGHT.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 3 PM FRIDAY...EXPECT SOUTHERLY RETURN FLOW TO CONTINUE
AROUND WESTERN PERIPHERY OF BERMUDA HIGH THROUGH THE WEEKEND. BY
SUNDAY AFTERNOON INTO SUNDAY NIGHT THE GRADIENT WILL BEGIN TO
TIGHTEN AS COLD FRONT APPROACHES THE CAROLINAS FROM THE WEST.
OVERALL EXPECT SOUTHERLY FLOW CLOSER TO 5 TO 10 KTS THROUGH THE
FIRST HALF OF THE WEEKEND AND UP TO 15 KTS BY SUN EVENING. THE
WAVE HEIGHTS WILL RESPOND TO INCREASE IN SOUTHERLY FLOW BY RISING
CLOSER TO 3 TO 4 FT BY SUN NIGHT. BASICALLY SEAS WILL HOLD
BETWEEN 2 AND 4 FT THROUGH THE WEEKEND. EXPECT A SLIGHT SPIKE UP
IN WINDS AND SEAS EACH AFTN AND A SLIGHT CHOP NEAR SHORE IN SEA
BREEZE EACH AFTERNOON.
LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 300 PM FRIDAY...PRE-FRONTAL REGIME TO START THE PERIOD WITH
GUSTY SOUTHERLY WINDS ONGOING ACROSS THE WATERS. SOUTHERLY WINDS OF
10-15 KTS WILL BE THE RULE MONDAY...BEFORE VEERING TO THE WEST EARLY
TUESDAY. DO NOT EXPECT WINDS TO BECOME NORTHERLY AS FRONT STALLS AND
WASHES OUT OVER THE AREA DURING TUESDAY...AND EVENTUALLY WILL BACK
TO THE E/SE...AND FINALLY THE NE ON WEDNESDAY AS HIGH PRESSURE
RIDGES DOWN THE COAST. WHILE WIND SPEEDS WILL BE RELATIVELY LIGHT
TUESDAY...THEY WILL INCREASE TO AROUND 15 KTS WITHIN THE PINCHED
GRADIENT WEDNESDAY.
WHILE A 2FT/8SEC SE SWELL WILL PERSIST AND SLOWLY DAMPEN THROUGH THE
PERIOD...WIND WAVES WILL SHOW AN INCREASING CONTRIBUTION TO THE
SPECTRUM...ESPECIALLY MON AND WED. SEAS WILL BE GENERALLY 2-4 FT BUT
WITH SOME ISOLATED 5 FTERS MONDAY EVE AHEAD OF THE COLD FRONT...AND
AGAIN ON WEDNESDAY WITH THE STRONGER E/NE WINDS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...RGZ
LONG TERM...JDW
AVIATION...BJR
AREA FORECAST DISCUSSION
NWS RALEIGH NC
240 PM EDT FRI MAY 31 2013
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN SOLIDLY OVER THE REGION THROUGH
SATURDAY... THEN SHIFT OFFSHORE SUNDAY. A COLD FRONT WILL SLOWLY
APPROACH FROM THE WEST SUNDAY...THEN CROSS THE REGION MONDAY AND
MONDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 230 PM FRIDAY...
OVERVIEW:
AN UPPER LEVEL RIDGE CENTERED ALONG THE SOUTHEAST AND MID-ATLANTIC
COAST WILL FURTHER WEAKEN THROUGH TONIGHT AS AN UPPER LEVEL LOW
CENTERED OVER THE NORTHERN PLAINS MOVES SLOWLY EAST INTO THE
NORTHERN MS RIVER VALLEY. A SFC-H85 RIDGE WILL PERSIST OFFSHORE OF
THE CAROLINAS...WITH AN INCREASINGLY MOIST SOUTHERLY RETURN FLOW
ACROSS THE REGION.
TEMPERATURES:
HIGHS TODAY APPEAR VERY SIMILAR TO THE PREVIOUS FEW DAYS GIVEN
LITTLE CHANGE IN THICKNESSES AND A VERY SIMILAR (ALBEIT INCREASINGLY
MOIST) AIRMASS. THE MAIN FACTORS W/REGARD TO HIGH TEMPS ARE APT TO
BE THE SEABREEZE APPROACHING FROM THE S/SE AND ISOLD CONVECTION
/OUTFLOW/ EXPECTED DURING THE MID TO LATE AFTERNOON...PRIMARILY EAST
OF HWY 1 AND SOUTH OF HWY 64 (SANDHILL/SE COASTAL PLAIN) WHERE THE
SEABREEZE PASSAGE WILL OCCUR THE EARLIEST...THOUGH EVEN IN THOSE
AREAS DIURNAL HEATING MAY BE SUFFICIENT FOR TEMPS TO REACH THE UPPER
80S. WITH THE ABOVE IN MIND...WILL INDICATE HIGHS IN THE MID/UPPER
80S...WARMEST IN VICINITY OF HWY 1. EXPECT LOWS TONIGHT SLIGHTLY
WARMER THAN LAST NIGHT DUE TO INCREASED BOUNDARY LAYER MOISTURE...
IN THE MID/UPPER 60S.
CONVECTION:
WEAK BUT PERSISTENT SOUTHERLY RETURN FLOW WILL ADVECT AN
INCREASINGLY MOIST AIRMASS FROM THE ATLANTIC INTO CENTRAL NC...
CHARACTERIZED BY SFC DEWPOINTS IN THE MID/UPPER 60S...H925 DEWPOINTS
OF 13-15C AND H85 DEWPOINTS OF 10-12C DURING THE MID/LATE AFTERNOON
HOURS. MID-LEVEL LAPSE RATES HAVE DECREASED IN COMPARISON TO
YESTERDAY AS THE RIDGE ALOFT WEAKENS...AND THE LATEST RAP GUIDANCE
SUGGEST H7-H5 LAPSE RATES ON THE ORDER OF 5.5-6.5 C/KM DURING PEAK
HEATING...STEEPEST IN THE EAST. IN THIS ENVIRONMENT...EXPECT
MODERATE DESTABILIZATION WITH MLCAPE VALUES OF 1000-1500 J/KG BY
PEAK HEATING AND LITTLE OR NO CIN. FORCING WILL LARGELY BE LIMITED
TO CONVERGENCE ALONG THE SEABREEZE THIS AFTERNOON...THOUGH LATEST WV
IMAGERY AND RAP DATA SUGGEST A WEAK N-S ORIENTED H3 SHEAR AXIS OVER
THE SOUTHERN APPALACHIANS SHOULD PROGRESS SLOWLY EAST INTO THE
WESTERN PIEDMONT BY 21-00Z. WITH THE ABOVE IN MIND...EXPECT A
RELATIVELY MORE ACTIVE SEABREEZE THAN YESTERDAY...WITH ISOLD SHOWERS
AND PERHAPS A FEW STORMS BY LATE AFTERNOON...PRIMARILY SOUTH OF HWY
64 ACROSS THE EASTERN SANDHILLS AND SE COASTAL PLAIN...WITH ANY
ACTIVITY WANING IN VICINITY OF THE TRIANGLE OR HWY 1 CORRIDOR BY OR
SHORTLY AFTER SUNSET. CONVECTION WILL REMAIN DISORGANIZED GIVEN
NEGLIGIBLE DEEP-LAYER SHEAR UNDER THE WEAKENING RIDGE...THOUGH
MODERATE DCAPE (~1000 J/KG) WOULD SUGGEST SOME POTENTIAL FOR
ENHANCED COLD POOLS...PRIMARILY ACROSS SCOTLAND...HOKE...
CUMBERLAND...SAMPSON AND WAYNE COUNTIES BETWEEN 20-00Z. -VINCENT
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 230 PM FRIDAY...
SATURDAY AND SATURDAY NIGHT...
THOUGH THE UPPER LEVEL RIDGE WILL CONTINUE TO WEAKEN IN COMPARISON
TO PREVIOUS DAYS...RIDGING ALOFT WILL REMAIN IN PLACE OVER THE
CAROLINAS AS THE SLOW MOVING UPPER LEVEL TROUGH CURRENTLY OVER THE
CENTRAL PLAINS PROGRESSES EAST INTO THE TN/OH RIVER VALLEYS.
LOW-LEVEL MOISTURE AND PWAT VALUES ARE PROGGED TO FURTHER INCREASE
ACROSS CENTRAL NC ON SATURDAY...THOUGH MID-LEVEL LAPSE RATES WILL BE
SIMILAR OR SLIGHTLY WEAKER THAN TODAY AT 5.5-6.0 C/KM. DIURNAL
DESTABILIZATION SAT AFTERNOON SHOULD ALSO BE SIMILAR TO TODAY...
WITH ~1000 J/KG OF MLCAPE. FORCING WILL ONCE AGAIN BE LIMITED TO
WEAK LOW-LEVEL CONVERGENCE ALONG THE SEABREEZE...THOUGH INCREASING
W/SW FLOW ALOFT ACROSS WESTERN PORTIONS OF THE STATE MAY ALLOW FOR
SOME EASTWARD PROPAGATION OF ISOLD CONVECTION THAT DEVELOPS IN
ASSOC/W DIFFERENTIAL HEATING OVER THE HIGHER TERRAIN IN WESTERN NC.
WITH THIS IN MIND...WILL KEEP A SLIGHT CHANCE OF SHOWERS AND
THUNDERSTORMS IN THE S/SE AND WILL INTRODUCE A SLIGHT CHANCE IN THE
FAR WESTERN PIEDMONT AS WELL. EXPECT TEMPS SIMILAR TO PREVIOUS DAYS
WITH HIGHS IN THE UPPER 80S AND LOWS IN THE UPPER 60S...SLIGHTLY
WARMER THAN TONIGHT GIVEN A FURTHER INCREASE IN BOUNDARY LAYER
MOISTURE. -VINCENT
SUNDAY AND SUNDAY NIGHT...THE MID/UPPER LEVEL TROUGH THAT HAS WET
DOWN THE MIDWEST RECENTLY IS FORECAST TO FINALLY NUDGE EAST TOWARD
THE OHIO VALLEY AND CENTRAL APPALACHIANS SUNDAY AND SUNDAY NIGHT.
THE RIDGE OVER OUR REGION WILL BREAK DOWN AND SHIFT EAST ALLOWING
THE SURFACE HIGH PRESSURE TO MOVE OFFSHORE AS WELL. DEEP MOISTURE
(PRECIPITABLE WATER VALUES 150 TO 200 PERCENT OF NORMAL) FROM THE
GULF OF MEXICO IS FORECAST TO CONTINUE FEEDING NORTHWARD AHEAD OF
THE EASTWARD MOVING COLD FRONT THAT SHOULD BE APPROACHING THE
WESTERN SLOPES OF THE APPALACHIANS BY LATE SUNDAY. SEVERAL LINES OF
CONVECTION SHOULD BE ONGOING SUNDAY OVER EASTERN TN/KY... SPREADING
INTO THE MOUNTAINS OF NC/VA DURING THE AFTERNOON. SINCE MODELS
INDICATE THE BEST MID LEVEL HEIGHT FALLS TO OCCUR TO OUR WEST AND
NORTH INTO SUNDAY EVENING... MUCH OF THE DEEP CONVECTION WILL REMAIN
JUST TO OUR WEST AND NORTH UNTIL LATE AFTERNOON. HOWEVER...
SCATTERED DIURNALLY/TERRAIN DRIVEN THUNDERSTORMS ARE FAVORED ALONG
THE BLUE RIDGE DURING PEAK HEATING... POSSIBLY SPREADING OUT INTO
THE NW PIEDMONT DURING THE LATE AFTERNOON. WE WILL MAINTAIN THE
CHANCE POP FOR THE WINSTON-SALEM AND GREENSBORO AREAS SUNDAY
AFTERNOON. ELSEWHERE... PARTLY SUNNY SKIES AND CONTINUED WARM AND
HUMID. HIGHS 85-90.
BY SUNDAY EVENING AND OVERNIGHT...A LINE OF DEEP CONVECTION IS
SUPPORTED TO AFFECT PORTIONS OF OUR WESTERN AND NORTHERN PIEDMONT
DURING THE EVENING INTO THE OVERNIGHT HOURS. LOCALLY HEAVY RAIN IS
EXPECTED WITH THE PW`S FORECAST TO REACH 150-200 PERCENT OF NORMAL
AND SURFACE DEW POINTS NEARING 70. THIS ACTIVITY MAY CONTINUE TO
ADVANCE SLOWLY EASTWARD THROUGH THE PIEDMONT OVERNIGHT... WITH A
CHANCE OF THE ACTIVITY SPREADING INTO THE SANDHILLS AND WESTERN
COASTAL PLAIN WELL AFTER MIDNIGHT. WE HAVE LIKELY POP IN THE WEST
AND NORTH... WITH CHANCE POP EAST AND SOUTH OF THAT AREA OVERNIGHT.
A SSW LOW LEVEL FLOW OF 10-15 MPH WILL KEEP TEMPERATURES IN THE
LOWER TO MID 70S EXCEPT UPPER 60S IN THE RAIN COOLED NW PIEDMONT BY
12Z/MON. THE SEVERE THREAT APPEARS MARGINAL FOR NOW... WITH THE MAIN
DYNAMICS WELL TO THE NW. HOWEVER... LOCALLY HEAVY RAIN WITH SLOW
MOVING AND TRAINING OF STORMS WILL BE POSSIBLE IN THE NW.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 210 PM FRIDAY...
AT LEAST SOME CONVECTION SHOULD BE ONGOING IN A WEAKENED STATE AT
DAYBREAK MONDAY. IT IS TOO EARLY TO TELL HOW FAR EAST THE PREVIOUS
NIGHTS CONVECTION WILL MAKE IT... BUT CONVECTIVE OUTFLOW BOUNDARIES
SHOULD PLAY A CRITICAL ROLE IN THE CONVECTIVE EVOLUTION MONDAY. THE
MAIN COLD FRONT IS FORECAST TO BE ALONG THE EASTERN SLOPES OF THE
BLUE RIDGE AT 12Z... THEN SLOWLY PUSH ESE THROUGH CENTRAL NORTH
CAROLINA MONDAY AFTERNOON AND EVENING. THERE MAY BE SEVERAL BANDS OF
CONVECTION THAT DEVELOP AND AFFECT THE REGION MONDAY. THE FIRST WITH
THE RESIDUAL OUTFLOWS AND THE NEXT ALONG OR AHEAD OF THE ACTUAL COLD
FRONT. WE WILL MAINTAIN THE LIKELY POP IN A BROAD BRUSH FASHION
MONDAY... THEN CONTINUE THE TREND OF TAPERING POP FROM THE NW MONDAY
EVENING AND NIGHT. HOWEVER... DUE TO THE EXPECTED SLOW MOVEMENT OF
THE COLD FRONT (SHOULD BE NEAR THE COAST BY 12Z TUESDAY)... LOCALLY
HEAVY RAIN CAN FOCUS/OCCUR OVER THE REGION THROUGH 12Z/TUE). THE FAR
NW ZONES SHOULD (BEGIN/END) FIRST WITH THIS HEAVY RAIN THREATS.
COOLER CONDITIONS WILL PREVAIL DUE TO THE RAIN/CLOUDS MONDAY... THEN
THE CAA WITH THE NE LOW LEVEL FLOW BEGINNING TUESDAY. INDICATIONS
ARE THAT CLOUDINESS AND THE THREAT OF RAIN MAY CONTINUE TUESDAY AS A
SECONDARY WAVE MAY FORM ALONG THE FRONT OVER COASTAL SC. WE WILL
KEEP AT LEAST SOME POP CHANCES IN THE EAST AND SOUTH TUESDAY. LOWS
60-68. HIGHS TUESDAY 75-82.
WEDNESDAY THROUGH FRIDAY... SLIGHTLY DRIER MID LEVELS... ASSOCIATED
WITH MID LEVEL RIDGING AND A MODERATELY STRONG (1026+ MB) SURFACE
HIGH PRESSURE EXTENDING FROM PA/NY INTO NC/SC WED-THU... IS
INDICATED. HOWEVER... THE NE BECOMING E LOW LEVEL FLOW SUGGESTS LATE
NIGHT AND MORNING CLOUDINESS BOTH DAYS WED-THU. LOWS 57-64. HIGHS
78-83.
BY FRIDAY... ANOTHER APPROACHING MID/UPPER LEVEL TROUGH FROM THE
CENTRAL U.S. SHOULD BEGIN TO AFFECT THE REGION. HOWEVER... WE WILL
MAINTAIN SLIGHT CHANCES FOR NOW ON DAY 7. IN GENERAL... VARIABLY
CLOUDY WITH A SE FLOW WILL CONTINUE MILD DAYS INTO FRIDAY. LOWS IN
THE 60S. HIGHS FRIDAY IN THE LOWER TO MID 80S.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 1220 PM FRIDAY...
24-HR TAF PERIOD:
VFR CONDITIONS WITH CEILINGS BETWEEN 4000-5000 FT AGL WILL PREVAIL
IN MOST AREAS THROUGH THIS EVENING...ASIDE FROM A CHANCE OF ISOLD
SHOWERS AND STORMS BETWEEN 20-00Z...PRIMARILY AT THE FAY TERMINAL...
THOUGH POSSIBLY AS FAR NORTH AS THE RDU/RWI TERMINALS PRIOR TO
DISSIPATING. OVERNIGHT...EXPECT A GOOD POTENTIAL FOR IFR/LIFR
STRATUS OR FOG AT ALL TERMINALS BETWEEN 07-13Z SAT...WITH ANY
FOG/STRATUS LIFTING TO VFR BY MID SAT MORNING. VFR CONDITIONS WITH
CEILINGS 4000-5000 FT AGL ARE EXPECTED DURING THE DAY SATURDAY.
LOOKING AHEAD:
MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE ANTICIPATED ALONG AND
AHEAD OF A COLD FRONT PROGRESSING SLOWLY EAST THROUGH CENTRAL NC SUN
NIGHT AND MONDAY...BEGINNING IN THE WESTERN PIEDMONT (INT/GSO
TERMINALS) LATE SUNDAY AFT/EVE...EVENTUALLY ENDING FROM WEST TO EAST
LATE MON INTO MON NIGHT. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...PWB
NEAR TERM...VINCENT
SHORT TERM...VINCENT/PWB
LONG TERM...PWB
AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS RALEIGH NC
210 PM EDT FRI MAY 31 2013
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN SOLIDLY OVER THE REGION THROUGH
SATURDAY... THEN SHIFT OFFSHORE SUNDAY. A COLD FRONT WILL SLOWLY
APPROACH FROM THE WEST SUNDAY...THEN CROSS THE REGION MONDAY AND
MONDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1130 AM FRIDAY...
OVERVIEW:
AN UPPER LEVEL RIDGE CENTERED ALONG THE SOUTHEAST AND MID-ATLANTIC
COAST WILL FURTHER WEAKEN THROUGH TONIGHT AS AN UPPER LEVEL LOW
CENTERED OVER THE NORTHERN PLAINS MOVES SLOWLY EAST INTO THE
NORTHERN MS RIVER VALLEY. A SFC-H85 RIDGE WILL PERSIST OFFSHORE OF
THE CAROLINAS...WITH AN INCREASINGLY MOIST SOUTHERLY RETURN FLOW
ACROSS THE REGION.
TEMPERATURES:
HIGHS TODAY APPEAR VERY SIMILAR TO THE PREVIOUS FEW DAYS GIVEN
LITTLE CHANGE IN THICKNESSES AND A VERY SIMILAR (ALBEIT INCREASINGLY
MOIST) AIRMASS. THE MAIN FACTORS W/REGARD TO HIGH TEMPS ARE APT TO
BE THE SEABREEZE APPROACHING FROM THE S/SE AND ISOLD CONVECTION
/OUTFLOW/ EXPECTED DURING THE MID TO LATE AFTERNOON...PRIMARILY EAST
OF HWY 1 AND SOUTH OF HWY 64 (SANDHILL/SE COASTAL PLAIN) WHERE THE
SEABREEZE PASSAGE WILL OCCUR THE EARLIEST...THOUGH EVEN IN THOSE
AREAS DIURNAL HEATING MAY BE SUFFICIENT FOR TEMPS TO REACH THE UPPER
80S. WITH THE ABOVE IN MIND...WILL INDICATE HIGHS IN THE MID/UPPER
80S...WARMEST IN VICINITY OF HWY 1. EXPECT LOWS TONIGHT SLIGHTLY
WARMER THAN LAST NIGHT DUE TO INCREASED BOUNDARY LAYER MOISTURE...
IN THE MID/UPPER 60S.
CONVECTION:
WEAK BUT PERSISTENT SOUTHERLY RETURN FLOW WILL ADVECT AN
INCREASINGLY MOIST AIRMASS FROM THE ATLANTIC INTO CENTRAL NC...
CHARACTERIZED BY SFC DEWPOINTS IN THE MID/UPPER 60S...H925 DEWPOINTS
OF 13-15C AND H85 DEWPOINTS OF 10-12C DURING THE MID/LATE AFTERNOON
HOURS. MID-LEVEL LAPSE RATES HAVE DECREASED IN COMPARISON TO
YESTERDAY AS THE RIDGE ALOFT WEAKENS...AND THE LATEST RAP GUIDANCE
SUGGEST H7-H5 LAPSE RATES ON THE ORDER OF 5.5-6.5 C/KM DURING PEAK
HEATING...STEEPEST IN THE EAST. IN THIS ENVIRONMENT...EXPECT
MODERATE DESTABILIZATION WITH MLCAPE VALUES OF 1000-1500 J/KG BY
PEAK HEATING AND LITTLE OR NO CIN. FORCING WILL LARGELY BE LIMITED
TO CONVERGENCE ALONG THE SEABREEZE THIS AFTERNOON...THOUGH LATEST WV
IMAGERY AND RAP DATA SUGGEST A WEAK N-S ORIENTED H3 SHEAR AXIS OVER
THE SOUTHERN APPALACHIANS SHOULD PROGRESS SLOWLY EAST INTO THE
WESTERN PIEDMONT BY 21-00Z. WITH THE ABOVE IN MIND...EXPECT A MORE
ACTIVE SEABREEZE THAN YESTERDAY...WITH ISOLD TO SCT SHOWERS AND
STORMS BETWEEN BY MID/LATE AFTERNOON...PRIMARILY SOUTH OF HWY 64
ACROSS THE EASTERN SANDHILLS AND SE COASTAL PLAIN...WITH ACTIVITY
WANING IN VICINITY OF THE TRIANGLE OR HWY 1 CORRIDOR BY OR SHORTLY
AFTER SUNSET. CONVECTION WILL REMAIN DISORGANIZED GIVEN NEGLIGIBLE
DEEP-LAYER SHEAR UNDER THE WEAKENING RIDGE...THOUGH MODERATE DCAPE
(~1000 J/KG) WOULD SUGGEST SOME POTENTIAL FOR ENHANCED COLD POOLS
AND PERHAPS AN ISOLD DOWNBURST...PRIMARILY ACROSS SCOTLAND...HOKE...
CUMBERLAND...SAMPSON AND WAYNE COUNTIES BETWEEN 19-23Z. -VINCENT
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 210 PM FRIDAY...
SATURDAY AND SATURDAY NIGHT...
SUNDAY AND SUNDAY NIGHT... THE MID/UPPER LEVEL TROUGH THAT HAS WET
DOWN THE MIDWEST RECENTLY IS FORECAST TO FINALLY NUDGE EAST TOWARD
THE OHIO VALLEY AND CENTRAL APPALACHIANS SUNDAY AND SUNDAY NIGHT.
THE RIDGE OVER OUR REGION WILL BREAK DOWN AND SHIFT EAST ALLOWING
THE SURFACE HIGH PRESSURE TO MOVE OFFSHORE AS WELL. DEEP MOISTURE
(PRECIPITABLE WATER VALUES 150 TO 200 PERCENT OF NORMAL) FROM THE
GULF OF MEXICO IS FORECAST TO CONTINUE FEEDING NORTHWARD AHEAD OF
THE EASTWARD MOVING COLD FRONT THAT SHOULD BE APPROACHING THE
WESTERN SLOPES OF THE APPALACHIANS BY LATE SUNDAY. SEVERAL LINES OF
CONVECTION SHOULD BE ONGOING SUNDAY OVER EASTERN TN/KY... SPREADING
INTO THE MOUNTAINS OF NC/VA DURING THE AFTERNOON. SINCE MODELS
INDICATE THE BEST MID LEVEL HEIGHT FALLS TO OCCUR TO OUR WEST AND
NORTH INTO SUNDAY EVENING... MUCH OF THE DEEP CONVECTION WILL REMAIN
JUST TO OUR WEST AND NORTH UNTIL LATE AFTERNOON. HOWEVER...
SCATTERED DIURNALLY/TERRAIN DRIVEN THUNDERSTORMS ARE FAVORED ALONG
THE BLUE RIDGE DURING PEAK HEATING... POSSIBLY SPREADING OUT INTO
THE NW PIEDMONT DURING THE LATE AFTERNOON. WE WILL MAINTAIN THE
CHANCE POP FOR THE WINSTON-SALEM AND GREENSBORO AREAS SUNDAY
AFTERNOON. ELSEWHERE... PARTLY SUNNY SKIES AND CONTINUED WARM AND
HUMID. HIGHS 85-90.
BY SUNDAY EVENING AND OVERNIGHT... A LINE OF DEEP CONVECTION IS
SUPPORTED TO AFFECT PORTIONS OF OUR WESTERN AND NORTHERN PIEDMONT
DURING THE EVENING INTO THE OVERNIGHT HOURS. LOCALLY HEAVY RAIN IS
EXPECTED WITH THE PW`S FORECAST TO REACH 150-200 PERCENT OF NORMAL
AND SURFACE DEW POINTS NEARING 70. THIS ACTIVITY MAY CONTINUE TO
ADVANCE SLOWLY EASTWARD THROUGH THE PIEDMONT OVERNIGHT... WITH A
CHANCE OF THE ACTIVITY SPREADING INTO THE SANDHILLS AND WESTERN
COASTAL PLAIN WELL AFTER MIDNIGHT. WE HAVE LIKELY POP IN THE WEST
AND NORTH... WITH CHANCE POP EAST AND SOUTH OF THAT AREA OVERNIGHT.
A SSW LOW LEVEL FLOW OF 10-15 MPH WILL KEEP TEMPERATURES IN THE
LOWER TO MID 70S EXCEPT UPPER 60S IN THE RAIN COOLED NW PIEDMONT BY
12Z/MON. THE SEVERE THREAT APPEARS MARGINAL FOR NOW... WITH THE MAIN
DYNAMICS WELL TO THE NW. HOWEVER... LOCALLY HEAVY RAIN WITH SLOW
MOVING AND TRAINING OF STORMS WILL BE POSSIBLE IN THE NW.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 210 PM FRIDAY...
AT LEAST SOME CONVECTION SHOULD BE ONGOING IN A WEAKENED STATE AT
DAYBREAK MONDAY. IT IS TOO EARLY TO TELL HOW FAR EAST THE PREVIOUS
NIGHTS CONVECTION WILL MAKE IT... BUT CONVECTIVE OUTFLOW BOUNDARIES
SHOULD PLAY A CRITICAL ROLE IN THE CONVECTIVE EVOLUTION MONDAY. THE
MAIN COLD FRONT IS FORECAST TO BE ALONG THE EASTERN SLOPES OF THE
BLUE RIDGE AT 12Z... THEN SLOWLY PUSH ESE THROUGH CENTRAL NORTH
CAROLINA MONDAY AFTERNOON AND EVENING. THERE MAY BE SEVERAL BANDS OF
CONVECTION THAT DEVELOP AND AFFECT THE REGION MONDAY. THE FIRST WITH
THE RESIDUAL OUTFLOWS AND THE NEXT ALONG OR AHEAD OF THE ACTUAL COLD
FRONT. WE WILL MAINTAIN THE LIKELY POP IN A BROAD BRUSH FASHION
MONDAY... THEN CONTINUE THE TREND OF TAPERING POP FROM THE NW MONDAY
EVENING AND NIGHT. HOWEVER... DUE TO THE EXPECTED SLOW MOVEMENT OF
THE COLD FRONT (SHOULD BE NEAR THE COAST BY 12Z TUESDAY)... LOCALLY
HEAVY RAIN CAN FOCUS/OCCUR OVER THE REGION THROUGH 12Z/TUE). THE FAR
NW ZONES SHOULD (BEGIN/END) FIRST WITH THIS HEAVY RAIN THREATS.
COOLER CONDITIONS WILL PREVAIL DUE TO THE RAIN/CLOUDS MONDAY... THEN
THE CAA WITH THE NE LOW LEVEL FLOW BEGINNING TUESDAY. INDICATIONS
ARE THAT CLOUDINESS AND THE THREAT OF RAIN MAY CONTINUE TUESDAY AS A
SECONDARY WAVE MAY FORM ALONG THE FRONT OVER COASTAL SC. WE WILL
KEEP AT LEAST SOME POP CHANCES IN THE EAST AND SOUTH TUESDAY. LOWS
60-68. HIGHS TUESDAY 75-82.
WEDNESDAY THROUGH FRIDAY... SLIGHTLY DRIER MID LEVELS... ASSOCIATED
WITH MID LEVEL RIDGING AND A MODERATELY STRONG (1026+ MB) SURFACE
HIGH PRESSURE EXTENDING FROM PA/NY INTO NC/SC WED-THU... IS
INDICATED. HOWEVER... THE NE BECOMING E LOW LEVEL FLOW SUGGESTS LATE
NIGHT AND MORNING CLOUDINESS BOTH DAYS WED-THU. LOWS 57-64. HIGHS
78-83.
BY FRIDAY... ANOTHER APPROACHING MID/UPPER LEVEL TROUGH FROM THE
CENTRAL U.S. SHOULD BEGIN TO AFFECT THE REGION. HOWEVER... WE WILL
MAINTAIN SLIGHT CHANCES FOR NOW ON DAY 7. IN GENERAL... VARIABLY
CLOUDY WITH A SE FLOW WILL CONTINUE MILD DAYS INTO FRIDAY. LOWS IN
THE 60S. HIGHS FRIDAY IN THE LOWER TO MID 80S.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 1220 PM FRIDAY...
24-HR TAF PERIOD:
VFR CONDITIONS WITH CEILINGS BETWEEN 4000-5000 FT AGL WILL PREVAIL
IN MOST AREAS THROUGH THIS EVENING...ASIDE FROM A CHANCE OF ISOLD
SHOWERS AND STORMS BETWEEN 20-00Z...PRIMARILY AT THE FAY TERMINAL...
THOUGH POSSIBLY AS FAR NORTH AS THE RDU/RWI TERMINALS PRIOR TO
DISSIPATING. OVERNIGHT...EXPECT A GOOD POTENTIAL FOR IFR/LIFR
STRATUS OR FOG AT ALL TERMINALS BETWEEN 07-13Z SAT...WITH ANY
FOG/STRATUS LIFTING TO VFR BY MID SAT MORNING. VFR CONDITIONS WITH
CEILINGS 4000-5000 FT AGL ARE EXPECTED DURING THE DAY SATURDAY.
LOOKING AHEAD:
MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE ANTICIPATED ALONG AND
AHEAD OF A COLD FRONT PROGRESSING SLOWLY EAST THROUGH CENTRAL NC SUN
NIGHT AND MONDAY...BEGINNING IN THE WESTERN PIEDMONT (INT/GSO
TERMINALS) LATE SUNDAY AFT/EVE...EVENTUALLY ENDING FROM WEST TO EAST
LATE MON INTO MON NIGHT. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...PWB/V
NEAR TERM...V
SHORT TERM...V/PWB
LONG TERM...PWB
AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
116 PM EDT FRI MAY 31 2013
.SYNOPSIS...
BERMUDA HIGH PRESSURE WILL CONTINUE ACROSS THE CAROLINAS THROUGH THE
WEEKEND. A COLD FRONT WILL SLOWLY MOVE THROUGH THE AREA EARLY NEXT
WEEK...BRINGING THE HIGHEST POTENTIAL FOR SHOWERS AND THUNDERSTORMS
MONDAY AND TUESDAY. HIGH PRESSURE WILL SLOWLY BUILD SOUTHWARD AND
INTO THE AREA DURING THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 130 PM FRIDAY...SHOWER/T-STORM ACTIVITY IS CENTERED ALONG TWO
PORTIONS OF THE SEABREEZE BOUNDARY: CENTRAL HORRY COUNTY AND THE
CAPE FEAR RIVER JUST NW OF WILMINGTON. THIS ACTIVITY SHOULD MAINTAIN
ITSELF OR PERHAPS WEAKEN SLIGHTLY AS IT MOVES NORTHWARD THROUGH THE
NEXT FEW HOURS. ISOLATED SHOWERS WILL PROBABLY DEVELOP BACK ACROSS
THE PEE DEE REGION AS WELL. SMALL DOWNWARD ADJUSTMENTS TO
TEMPERATURES HAVE BEEN MADE NEAR THE COAST WHERE CLOUDINESS AND
SHOWERS HAVE HELD TEMPERATURES DOWN. PREVIOUS DISCUSSION FROM 1130
AM FOLLOWS...
JUST A QUICK NEAR-TERM UPDATE TO INCREASE POPS ALONG AND WEST OF THE
SEABREEZE BOUNDARY. CURRENT RADAR LOOKS A LITTLE MORE ACTIVE THAN I
HAD ANTICIPATED WITH EXCELLENT MOISTURE POOLING ALONG THE BOUNDARY
WITHIN THE REGION OF STEEP LOW LEVEL LAPSE RATES. NO OTHER
SIGNIFICANT CHANGES. PREVIOUS DISCUSSION FROM 1030 AM FOLLOWS...
BERMUDA HIGH PRESSURE EXTENDS WESTWARD INTO THE CAROLINAS AGAIN
TODAY. THIS MEANS A CONTINUATION OF SEASONABLY WARM AND MOIST
ONSHORE WINDS. THE MOISTURE CONTENT OF THIS AIRMASS HAS GROWN OVER
THE PAST COUPLE OF DAYS...AND THIS COULD BE TERMED A MARITIME
TROPICAL AIRMASS WITH SURFACE DEWPOINTS AROUND 70 DEGREES F AND
PRECIPITABLE WATER VALUES CLIMBING TO 1.4 INCHES. THE PRECIPITABLE
WATER WOULD BE HIGHER IF IT WEREN`T FOR A CONSIDERABLE LAYER OF DRY
AIR LURKING AT AND ABOVE 700 MB WHERE DEWPOINT DEPRESSIONS ARE IN
EXCESS OF 30 DEGREES F.
THERMALLY THERE IS ONLY A HINT OF A SUBSIDENCE INVERSION AROUND 700
MB/10000 FT AGL TODAY. LAPSE RATES BELOW THIS LEVEL ARE STEEP ENOUGH
TO ENSURE WE GET LOTS OF TOWERING CUMULUS TODAY WITH ISOLATED
SHOWERS ALONG AND WEST OF THE SEABREEZE BOUNDARY. A FEW SHOWERS MAY
BREAK THROUGH THIS WEAK CONVECTIVE CAP AND BECOME THUNDERSTORMS THIS
AFTERNOON...BUT ALL THE DRY AIR ALOFT SHOULD MIX INTO THE UPDRAFTS
AND WEAKEN THESE STORMS IN SHORT ORDER. COVERAGE OF SHOWERS/STORMS
INLAND FROM THE COAST SHOULD BE 20-25 PERCENT THIS TODAY.
HIGH TEMPERATURES WILL END UP VERY CLOSE TO YESTERDAY`S READINGS:
UPPER 80S INLAND WITH LOWER TO MID 80S CLOSER TO THE COAST. THE
BEACHES WILL TOP OUT AROUND 80 WITH A SLIGHTLY COOLER MARINE AIRMASS
PUSHING ONSHORE.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 245 AM FRIDAY...MID LEVEL HEIGHTS WILL SLOWLY DECREASE THROUGH
THE PERIOD WITH MOISTURE PROFILES FLUCTUATING SOMEWHAT. BERMUDA HIGH
PRESSURE CONTINUE TO BE THE MAIN FIXTURE AT THE SURFACE. MOISTURE
PROFILES ARE ACTUALLY A LITTLE HIGHER SATURDAY AND I HAVE INCLUDED
LOW CHANCE POPS FOR MOST INLAND AREAS FOR THE AFTERNOON HOURS.
SUNDAY SHOULD BE MOSTLY DRY AS PRECIPITABLE WATER VALUES ACTUALLY
DROP DURING THE DAY WHEN COMPARED TO SATURDAY. CONTINUED TO TREND
POPS SLOWLY UPWARD SUNDAY NIGHT INTO MONDAY MORNING VIA THE LONG
ADVERTISED TROUGH AND ASSOCIATED COLD FRONT MOVING CLOSER. NUMERICAL
GUIDANCE HAS WARMED SLIGHTLY WITH REGARDS TO TEMPERATURES AS HAS THE
OFFICIAL FORECAST.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 245 AM FRIDAY...THE ECMWF ENSEMBLE MEAN CONTINUES TO BE THE
FAVORED MODEL OF WPC AND THIS WARRANTS ONLY COSMETIC CHANGES TO THE
EXTENDED FORECAST. OVERALL THE AMPLITUDE HAS DECREASED A BIT BUT
STILL EXPECT THE HIGHEST POPS MONDAY AND MONDAY NIGHT AS THE MID AND
LOW LEVEL FORCING IS COUPLED. RESIDUAL LOWER POPS ARE NOW ADVERTISED
IN THE DAYS BEYOND MONDAY AND THIS SEEMS REASONABLE GIVING THE TREND
TOWARD LOWER AMPLITUDE LEADING TO LOWER CONFIDENCE THE FRONT WILL
CLEAR THE AREA.
&&
.AVIATION /12Z FRIDAY THROUGH WEDNESDAY/...
AS OF 18Z...RADAR IMAGERY SHOWS SCATTERED SHOWERS/T-STORMS
DEVELOPING ALONG THE SEA BREEZE BOUNDARY THIS AFTN. HAVE INCLUDED
VCSH FOR KFLO/KLBT AS LATEST HRRR RUNS SHOW MORE SHOWERS DEVELOPING
INLAND LATER TODAY. OTHERWISE...VFR SHOULD PREVAIL WITH SCT/BKN CU
AND SSE WINDS AOB 10 KTS. MOSTLY CLEAR CONDITIONS TONIGHT AND PLENTY
OF LOW-LEVEL MOISTURE INDICATES FOG/STRATUS IS AGAIN LIKELY AFTER
06Z. SREF PROBS AND GUIDANCE SUGGEST IFR CIGS/VSBYS WILL BE MORE
WIDESPREAD INLAND...SIMILAR TO WHAT OCCURRED THIS MORNING. TEMPO IFR
IS ALSO QUITE POSSIBLE ALONG THE COAST...MOST LIKELY IN THE 09-12Z
RANGE. FOG/STRATUS SHOULD LIFT SOON AFTER 12Z SATURDAY.
EXTENDED OUTLOOK...EARLY MORNING MVFR/IFR CIGS/VSBYS POSSIBLE
THROUGH SUNDAY. SLIGHT CHANCE OF SHOWERS INLAND ON SUNDAY...WITH
BETTER PCPN CHANCES ACROSS THE CWA MONDAY AND TUESDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 130 PM FRIDAY...A FAIRLY LARGE AREA OF SHOWERS 10-30 MILES
INLAND FROM THE COAST HAS KEPT INLAND TEMPERATURES A FEW DEGREES
COOLER THAN EXPECTED...AND THIS HAS DELAYED THE INTENSIFICATION OF
THE SEABREEZE BY A FEW HOURS. SOUTHEAST WINDS SHOULD STILL INCREASE
TO A SOLID 10-12 KNOTS WITH GUSTS TOWARD 15 KNOTS IN THE NEXT COUPLE
OF HOURS. NO OTHER SIGNIFICANT CHANGES. PREVIOUS DISCUSSION FROM
1030 AM FOLLOWS...
BERMUDA HIGH PRESSURE WELL OFFSHORE CONTINUES TO EXTEND A RIDGE AXIS
ACROSS THE CAROLINAS WITH LIGHT ONSHORE WINDS THE RESULT. MUCH LIKE
YESTERDAY...MODEST MARINE-TO-INLAND TEMPERATURE CONTRASTS WILL FUEL
A WEAK SEABREEZE WITH WIND SPEEDS NEARSHORE INCREASING TO 12-14
KNOTS. SHOWERS OUT TOWARD 40 MILES FROM SHORE AND NEW SHOWERS
DEVELOPING JUST INLAND FROM THE BEACHES SHOULD AVOID THE COASTAL
WATERS THROUGH THE DAY...WITH MAINLY SUNNY SKIES EXPECTED. SEAS
AVERAGE 2.5 TO 3 FEET ON THE BUOYS NEAR CAPE FEAR THIS
MORNING...WITH WAVE ENERGY EQUALLY SPLIT BETWEEN 6 AND 9 SECOND
PERIODS.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 245 AM FRIDAY...BERMUDA HIGH PRESSURE CIRCULATION WILL BRING
SEAS AROUND THREE FEET IN 7-8 SECOND INTERVALS. SOME ACCELERATION
AND SLIGHTLY CHOPPIER SEAS CAN BE EXPECTED EACH AFTERNOON CLOSER
TO SHORE VIA THE SEA BREEZE.
LONG TERM /MONDAY THROUGH TUESDAY/...
AS OF 245 AM FRIDAY...SOUTH TO SOUTHWESTERLY WINDS THROUGH MOST OF
THE PERIOD AS THE WIND SHIFT ASSOCIATED WITH THE FRONT WILL TAKE
SOME TIME TO OCCUR. BY WEDNESDAY MORNING EXPECT A WEAK NORTHEASTERLY
FLOW TO BE IN PLACE. CERTAINLY NO STRONG PUSH OF COLD AIR BEHIND THE
FRONT AND OVERALL EXPECT WINDS TO BE IN A 10-15 KNOT RANGE.
SIGNIFICANT SEAS REMAIN IN A 2-3 FOOT RANGE A SLIGHT DECREASE FROM
EARLIER FORECASTS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...BJR
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1220 PM EDT FRI MAY 31 2013
.SYNOPSIS...
A COLD FRONT WILL SLOWLY APPROACH FROM THE WEST THIS WEEKEND...THEN
CROSS THE REGION SUNDAY NIGHT THROUGH MONDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1130 AM FRIDAY...
OVERVIEW:
AN UPPER LEVEL RIDGE CENTERED ALONG THE SOUTHEAST AND MID-ATLANTIC
COAST WILL FURTHER WEAKEN THROUGH TONIGHT AS AN UPPER LEVEL LOW
CENTERED OVER THE NORTHERN PLAINS MOVES SLOWLY EAST INTO THE
NORTHERN MS RIVER VALLEY. A SFC-H85 RIDGE WILL PERSIST OFFSHORE OF
THE CAROLINAS...WITH AN INCREASINGLY MOIST SOUTHERLY RETURN FLOW
ACROSS THE REGION.
TEMPERATURES:
HIGHS TODAY APPEAR VERY SIMILAR TO THE PREVIOUS FEW DAYS GIVEN
LITTLE CHANGE IN THICKNESSES AND A VERY SIMILAR (ALBEIT INCREASINGLY
MOIST) AIRMASS. THE MAIN FACTORS W/REGARD TO HIGH TEMPS ARE APT TO
BE THE SEABREEZE APPROACHING FROM THE S/SE AND ISOLD CONVECTION
/OUTFLOW/ EXPECTED DURING THE MID TO LATE AFTERNOON...PRIMARILY EAST
OF HWY 1 AND SOUTH OF HWY 64 (SANDHILL/SE COASTAL PLAIN) WHERE THE
SEABREEZE PASSAGE WILL OCCUR THE EARLIEST...THOUGH EVEN IN THOSE
AREAS DIURNAL HEATING MAY BE SUFFICIENT FOR TEMPS TO REACH THE UPPER
80S. WITH THE ABOVE IN MIND...WILL INDICATE HIGHS IN THE MID/UPPER
80S...WARMEST IN VICINITY OF HWY 1. EXPECT LOWS TONIGHT SLIGHTLY
WARMER THAN LAST NIGHT DUE TO INCREASED BOUNDARY LAYER MOISTURE...
IN THE MID/UPPER 60S.
CONVECTION:
WEAK BUT PERSISTENT SOUTHERLY RETURN FLOW WILL ADVECT AN
INCREASINGLY MOIST AIRMASS FROM THE ATLANTIC INTO CENTRAL NC...
CHARACTERIZED BY SFC DEWPOINTS IN THE MID/UPPER 60S...H925 DEWPOINTS
OF 13-15C AND H85 DEWPOINTS OF 10-12C DURING THE MID/LATE AFTERNOON
HOURS. MID-LEVEL LAPSE RATES HAVE DECREASED IN COMPARISON TO
YESTERDAY AS THE RIDGE ALOFT WEAKENS...AND THE LATEST RAP GUIDANCE
SUGGEST H7-H5 LAPSE RATES ON THE ORDER OF 5.5-6.5 C/KM DURING PEAK
HEATING...STEEPEST IN THE EAST. IN THIS ENVIRONMENT...EXPECT
MODERATE DESTABILIZATION WITH MLCAPE VALUES OF 1000-1500 J/KG BY
PEAK HEATING AND LITTLE OR NO CIN. FORCING WILL LARGELY BE LIMITED
TO CONVERGENCE ALONG THE SEABREEZE THIS AFTERNOON...THOUGH LATEST WV
IMAGERY AND RAP DATA SUGGEST A WEAK N-S ORIENTED H3 SHEAR AXIS OVER
THE SOUTHERN APPALACHIANS SHOULD PROGRESS SLOWLY EAST INTO THE
WESTERN PIEDMONT BY 21-00Z. WITH THE ABOVE IN MIND...EXPECT A MORE
ACTIVE SEABREEZE THAN YESTERDAY...WITH ISOLD TO SCT SHOWERS AND
STORMS BETWEEN BY MID/LATE AFTERNOON...PRIMARILY SOUTH OF HWY 64
ACROSS THE EASTERN SANDHILLS AND SE COASTAL PLAIN...WITH ACTIVITY
WANING IN VICINITY OF THE TRIANGLE OR HWY 1 CORRIDOR BY OR SHORTLY
AFTER SUNSET. CONVECTION WILL REMAIN DISORGANIZED GIVEN NEGLIGIBLE
DEEP-LAYER SHEAR UNDER THE WEAKENING RIDGE...THOUGH MODERATE DCAPE
(~1000 J/KG) WOULD SUGGEST SOME POTENTIAL FOR ENHANCED COLD POOLS
AND PERHAPS AN ISOLD DOWNBURST...PRIMARILY ACROSS SCOTLAND...HOKE...
CUMBERLAND...SAMPSON AND WAYNE COUNTIES BETWEEN 19-23Z. -VINCENT
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 300 AM FRIDAY...
SATURDAY/SATURDAY NIGHT...
WHILE HEIGHTS ALOFT BEGIN TO FALL EVER SO SLIGHTLY AHEAD OF THE
UPPER TROUGH MOVING INTO THE MID WEST STATES...THE MID-LEVEL RIDGE
OVER THE WESTERN ATLANTIC WILL REMAIN DOMINATE AS IT EXTENDS ACROSS
CENTRAL NC SATURDAY. THUS...EXPECT ANOTHER DAY OF AFTERNOON HIGHS
IN THE MID TO UPPER 80S AND ISOLATED SHOWERS POSSIBLE ALONG THE
SEABREEZE. MOISTURE TRANSPORT WILL BEGIN TO INCREASE ACROSS WESTERN
NC SATURDAY NIGHT AS THE MID-LEVEL RIDGE EASES EASTWARD. EXPECT A
FEW SHOWERS MAY BE POSSIBLE WEST OF THE YADKIN-RIVER...BUT WILL PLAN
TO KEEP THE RAH CWA DRY THROUGH 12Z...AWAITING THE ARRIVAL OF
STRONGER LOW-LEVEL FLOW AND DIURNAL HEATING. -SMITH
FOR SUNDAY/SUNDAY NIGHT: THE SLIGHTLY WEAKENING MID LEVEL TROUGH
AXIS APPROACHES OUR AREA FROM THE WEST... WITH MODELS DEPICTING A
WEAK PERTURBATION RIDING TO THE NORTHEAST UP THROUGH THE WRN/CENTRAL
CAROLINAS LATE SUNDAY INTO SUNDAY NIGHT... AS UPPER DIVERGENCE
INCREASES IN THE RIGHT ENTRANCE REGION OF A ST LAWRENCE VALLEY JET.
AS THE COLD FRONT APPROACHES FROM THE WEST... HIGH PRECIP WATER
(150-200% OF NORMAL) IS EXPECTED TO SURGE NORTHEASTWARD OVER WRN NC
SUNDAY AND INTO CENTRAL NC SUNDAY EVENING/NIGHT... ACCOMPANIED BY
INCREASING LOW LEVEL MOISTURE TRANSPORT. THE 50 KT LOW LEVEL JET
RIDES TO OUR NW ALONG THE CENTRAL APPALACHIANS EARLY SUNDAY BEFORE
SHIFTING UP INTO THE CANADIAN MARITIMES... LEAVING A MUCH MORE
SUBDUED 25-30 KT LOW LEVEL SPEED MAX FROM THE NRN PIEDMONT TO
COASTAL NEW ENGLAND... SO THE DYNAMIC FORCING FOR ASCENT AS WELL AS
THE KINEMATICS WILL GENERALLY BE RAMPING DOWN WITH MINIMAL DPVA.
INSTABILITY IS MARGINAL AS WELL WITH MODELS DEPICTING BRIEF MUCAPE
OF 1000-1500 J/KG OVER THE WRN CWA LATE SUNDAY WHILE THE SREF SHOWS
VERY LOW PROBABILITIES OF MLCAPE OVER 1000 J/KG AT ANY TIME...
LIKELY DUE IN PART TO WEAK MID LEVEL LAPSE RATES LESS THAN 6 C/KM.
BUT THE INCREASE IN MOISTURE AND WHAT WEAK LIFT THERE IS STILL SEEMS
TO SUPPORT CHANCE TO LOW-END LIKELY POPS SPREADING INTO AREAS WEST
OF HIGHWAY 1 LATE AFTERNOON AND THROUGH THE NIGHT. WILL ADJUST TO
BRING POPS EASTWARD A BIT LATER TO FIT WITH THE LATEST GUIDANCE
TIMING BUT WILL RETAIN THE GENERAL FLAVOR OF THE EARLIER FORECAST.
HIGHS 83-90... A LEAN TOWARD THE WARMER GFS-BASED STATISTICAL
GUIDANCE. ABOVE-GUIDANCE LOWS OF 68-72 WITHIN A PREFRONTAL WARM AIR
ADVECTION PATTERN. -GIH
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 245 AM FRIDAY...
FOR MONDAY/MONDAY NIGHT: BEST CHANCE OF SHOWERS/STORMS STILL LOOKS
TO BE IN THIS TIME FRAME. AS A STRONG VORTEX MOVES FROM SE ONTARIO
ACROSS SRN QUEBEC... THE WEAK SOUTHERN END OF THE TRAILING MID LEVEL
TROUGH EASES EASTWARD THROUGH THE AREA... ACCOMPANIED BY THE SURFACE
FRONT AND PRECEDED BY THE MINOR LOBE OF VORTICITY WHICH TRAVERSES
CENTRAL/ERN NC. THE ASCENT WILL BE ROOTED IN THE MID-UPPER LEVELS
WITH ONLY VERY WEAK MASS CONVERGENCE NEAR THE GROUND... BUT WITH
LIFT POTENTIALLY AUGMENTED BY 1000-1500 J/KG OF MLCAPE (FROM THE GFS
AND ECMWF)... IT SHOULD BE STRONG ENOUGH WITH THE EXPECTED DEEP
MOISTURE FOR LIKELY POPS AREAWIDE MONDAY... SLOWLY DECREASING WEST
TO EAST IN THE WEST MONDAY NIGHT BUT REMAINING LIKELY IN THE EAST.
CONFIDENCE IS HIGH THAT A PERIOD OF CATEGORICAL POPS WILL BE NEEDED
ONCE WE GET CLOSER AND CAN PIN DOWN TIMING A BIT BETTER. COULD SEE
UP TO AN INCH OF STORM-TOTAL RAIN BASED ON PRECIP WATER NEARING 2.0
INCHES AND A DEEP LCL-TO-0C LAYER AROUND 4 KM. HIGHS 77-84. LOWS
FROM 62 NW TO NEAR 70 SE.
FOR TUESDAY THROUGH THURSDAY: THE MID LEVEL SHEAR AXIS IS EXPECTED
TO SHIFT OFFSHORE BY TUESDAY MORNING WITH THE SURFACE FRONT DRIFTING
EASTWARD TO THE COASTAL AREA. THE ECMWF`S TROUGH IS NOTABLY WEAKER
AND MORE BAGGY THAN THE GFS`S... AND AS A RESULT THE ECMWF IS MUCH
SLOWER WITH THE FRONT... HANGING IT BACK FARTHER WEST... MEANING
CONTINUED WARM AIR/HIGH HUMIDITY AND RAIN CHANCES OVER ALL BUT THE
NW CWA. THINK THE ECMWF MAY BE ONTO SOMETHING GIVEN THAT THE
STRONGEST MID LEVEL FLOW WITH THE EASTERN CANADA LOW WILL HOLD NORTH
OF THE MASON-DIXON LINE. WILL HOLD ONTO AT LEAST CHANCE POPS FOR
SHOWERS SOUTH AND EAST OF RALEIGH THROUGH TUESDAY... WITH MORE
CLOUDS AND HIGHER DEW POINTS IN THE MID-UPPER 60S. THE QUEBEC VORTEX
LIFTS UP ACROSS ERN CANADA WHILE A SECOND LOW CROSSES THE DAKOTAS
TUESDAY NIGHT BEFORE SETTLING OVER THE UPPER MIDWEST THROUGH
MIDWEEK. FOR TUESDAY NIGHT THROUGH THURSDAY WE SHOULD BE UNDER THE
INFLUENCE OF THE CANADIAN SURFACE HIGH NOSING IN FROM THE NORTH
BENEATH WEAK MAINLY WESTERLY MID LEVEL FLOW... YIELDING FAIR SKIES
AND GENERALLY DRY CONDITIONS. THE RETURN EASTERLY FLOW AROUND THE
SURFACE HIGH STRENGTHENS BY THURSDAY WITH INCREASING ATLANTIC
INFLOW... AND THIS MAY RESULT IN A FEW SHOWERS OVER CENTRAL NC...
BUT THE CHANCE FOR SUFFICIENTLY DEEP MOISTURE IS TOO UNCERTAIN FOR
ANYTHING BUT SLIGHT CHANCE POPS FOR NOW. THICKNESSES SUPPORT TEMPS
NEAR NORMAL SE AND BELOW NORMAL NW ON TUESDAY... DROPPING TO ABOUT A
CATEGORY BELOW NORMAL FOR WEDNESDAY AND THURSDAY. -GIH
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 1220 PM FRIDAY...
24-HR TAF PERIOD:
VFR CONDITIONS WITH CEILINGS BETWEEN 4000-5000 FT AGL WILL PREVAIL
IN MOST AREAS THROUGH THIS EVENING...ASIDE FROM A CHANCE OF ISOLD
SHOWERS AND STORMS BETWEEN 20-00Z...PRIMARILY AT THE FAY TERMINAL...
THOUGH POSSIBLY AS FAR NORTH AS THE RDU/RWI TERMINALS PRIOR TO
DISSIPATING. OVERNIGHT...EXPECT A GOOD POTENTIAL FOR IFR/LIFR
STRATUS OR FOG AT ALL TERMINALS BETWEEN 07-13Z SAT...WITH ANY
FOG/STRATUS LIFTING TO VFR BY MID SAT MORNING. VFR CONDITIONS WITH
CEILINGS 4000-5000 FT AGL ARE EXPECTED DURING THE DAY SATURDAY.
LOOKING AHEAD:
MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE ANTICIPATED ALONG AND
AHEAD OF A COLD FRONT PROGRESSING SLOWLY EAST THROUGH CENTRAL NC SUN
NIGHT AND MONDAY...BEGINNING IN THE WESTERN PIEDMONT (INT/GSO
TERMINALS) LATE SUNDAY AFT/EVE...EVENTUALLY ENDING FROM WEST TO EAST
LATE MON INTO MON NIGHT. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT
SHORT TERM...SMITH/HARTFIELD
LONG TERM...HARTFIELD
AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1130 AM EDT FRI MAY 31 2013
.SYNOPSIS...
A COLD FRONT WILL SLOWLY APPROACH FROM THE WEST THIS WEEKEND...THEN
CROSS THE REGION SUNDAY NIGHT THROUGH MONDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1130 AM FRIDAY...
OVERVIEW:
AN UPPER LEVEL RIDGE CENTERED ALONG THE SOUTHEAST AND MID-ATLANTIC
COAST WILL FURTHER WEAKEN THROUGH TONIGHT AS AN UPPER LEVEL LOW
CENTERED OVER THE NORTHERN PLAINS MOVES SLOWLY EAST INTO THE
NORTHERN MS RIVER VALLEY. A SFC-H85 RIDGE WILL PERSIST OFFSHORE OF
THE CAROLINAS...WITH AN INCREASINGLY MOIST SOUTHERLY RETURN FLOW
ACROSS THE REGION.
TEMPERATURES:
HIGHS TODAY APPEAR VERY SIMILAR TO THE PREVIOUS FEW DAYS GIVEN
LITTLE CHANGE IN THICKNESSES AND A VERY SIMILAR (ALBEIT INCREASINGLY
MOIST) AIRMASS. THE MAIN FACTORS W/REGARD TO HIGH TEMPS ARE APT TO
BE THE SEABREEZE APPROACHING FROM THE S/SE AND ISOLD CONVECTION
/OUTFLOW/ EXPECTED DURING THE MID TO LATE AFTERNOON...PRIMARILY EAST
OF HWY 1 AND SOUTH OF HWY 64 (SANDHILL/SE COASTAL PLAIN) WHERE THE
SEABREEZE PASSAGE WILL OCCUR THE EARLIEST...THOUGH EVEN IN THOSE
AREAS DIURNAL HEATING MAY BE SUFFICIENT FOR TEMPS TO REACH THE UPPER
80S. WITH THE ABOVE IN MIND...WILL INDICATE HIGHS IN THE MID/UPPER
80S...WARMEST IN VICINITY OF HWY 1. EXPECT LOWS TONIGHT SLIGHTLY
WARMER THAN LAST NIGHT DUE TO INCREASED BOUNDARY LAYER MOISTURE...
IN THE MID/UPPER 60S.
CONVECTION:
WEAK BUT PERSISTENT SOUTHERLY RETURN FLOW WILL ADVECT AN
INCREASINGLY MOIST AIRMASS FROM THE ATLANTIC INTO CENTRAL NC...
CHARACTERIZED BY SFC DEWPOINTS IN THE MID/UPPER 60S...H925 DEWPOINTS
OF 13-15C AND H85 DEWPOINTS OF 10-12C DURING THE MID/LATE AFTERNOON
HOURS. MID-LEVEL LAPSE RATES HAVE DECREASED IN COMPARISON TO
YESTERDAY AS THE RIDGE ALOFT WEAKENS...AND THE LATEST RAP GUIDANCE
SUGGEST H7-H5 LAPSE RATES ON THE ORDER OF 5.5-6.5 C/KM DURING PEAK
HEATING...STEEPEST IN THE EAST. IN THIS ENVIRONMENT...EXPECT
MODERATE DESTABILIZATION WITH MLCAPE VALUES OF 1000-1500 J/KG BY
PEAK HEATING AND LITTLE OR NO CIN. FORCING WILL LARGELY BE LIMITED
TO CONVERGENCE ALONG THE SEABREEZE THIS AFTERNOON...THOUGH LATEST WV
IMAGERY AND RAP DATA SUGGEST A WEAK N-S ORIENTED H3 SHEAR AXIS OVER
THE SOUTHERN APPALACHIANS SHOULD PROGRESS SLOWLY EAST INTO THE
WESTERN PIEDMONT BY 21-00Z. WITH THE ABOVE IN MIND...EXPECT A MORE
ACTIVE SEABREEZE THAN YESTERDAY...WITH ISOLD TO SCT SHOWERS AND
STORMS BETWEEN BY MID/LATE AFTERNOON...PRIMARILY SOUTH OF HWY 64
ACROSS THE EASTERN SANDHILLS AND SE COASTAL PLAIN...WITH ACTIVITY
WANING IN VICINITY OF THE TRIANGLE OR HWY 1 CORRIDOR BY OR SHORTLY
AFTER SUNSET. CONVECTION WILL REMAIN DISORGANIZED GIVEN NEGLIGIBLE
DEEP-LAYER SHEAR UNDER THE WEAKENING RIDGE...THOUGH MODERATE DCAPE
(~1000 J/KG) WOULD SUGGEST SOME POTENTIAL FOR ENHANCED COLD POOLS
AND PERHAPS AN ISOLD DOWNBURST...PRIMARILY ACROSS SCOTLAND...HOKE...
CUMBERLAND...SAMPSON AND WAYNE COUNTIES BETWEEN 19-23Z. -VINCENT
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 300 AM FRIDAY...
SATURDAY/SATURDAY NIGHT...
WHILE HEIGHTS ALOFT BEGIN TO FALL EVER SO SLIGHTLY AHEAD OF THE
UPPER TROUGH MOVING INTO THE MID WEST STATES...THE MID-LEVEL RIDGE
OVER THE WESTERN ATLANTIC WILL REMAIN DOMINATE AS IT EXTENDS ACROSS
CENTRAL NC SATURDAY. THUS...EXPECT ANOTHER DAY OF AFTERNOON HIGHS
IN THE MID TO UPPER 80S AND ISOLATED SHOWERS POSSIBLE ALONG THE
SEABREEZE. MOISTURE TRANSPORT WILL BEGIN TO INCREASE ACROSS WESTERN
NC SATURDAY NIGHT AS THE MID-LEVEL RIDGE EASES EASTWARD. EXPECT A
FEW SHOWERS MAY BE POSSIBLE WEST OF THE YADKIN-RIVER...BUT WILL PLAN
TO KEEP THE RAH CWA DRY THROUGH 12Z...AWAITING THE ARRIVAL OF
STRONGER LOW-LEVEL FLOW AND DIURNAL HEATING. -SMITH
FOR SUNDAY/SUNDAY NIGHT: THE SLIGHTLY WEAKENING MID LEVEL TROUGH
AXIS APPROACHES OUR AREA FROM THE WEST... WITH MODELS DEPICTING A
WEAK PERTURBATION RIDING TO THE NORTHEAST UP THROUGH THE WRN/CENTRAL
CAROLINAS LATE SUNDAY INTO SUNDAY NIGHT... AS UPPER DIVERGENCE
INCREASES IN THE RIGHT ENTRANCE REGION OF A ST LAWRENCE VALLEY JET.
AS THE COLD FRONT APPROACHES FROM THE WEST... HIGH PRECIP WATER
(150-200% OF NORMAL) IS EXPECTED TO SURGE NORTHEASTWARD OVER WRN NC
SUNDAY AND INTO CENTRAL NC SUNDAY EVENING/NIGHT... ACCOMPANIED BY
INCREASING LOW LEVEL MOISTURE TRANSPORT. THE 50 KT LOW LEVEL JET
RIDES TO OUR NW ALONG THE CENTRAL APPALACHIANS EARLY SUNDAY BEFORE
SHIFTING UP INTO THE CANADIAN MARITIMES... LEAVING A MUCH MORE
SUBDUED 25-30 KT LOW LEVEL SPEED MAX FROM THE NRN PIEDMONT TO
COASTAL NEW ENGLAND... SO THE DYNAMIC FORCING FOR ASCENT AS WELL AS
THE KINEMATICS WILL GENERALLY BE RAMPING DOWN WITH MINIMAL DPVA.
INSTABILITY IS MARGINAL AS WELL WITH MODELS DEPICTING BRIEF MUCAPE
OF 1000-1500 J/KG OVER THE WRN CWA LATE SUNDAY WHILE THE SREF SHOWS
VERY LOW PROBABILITIES OF MLCAPE OVER 1000 J/KG AT ANY TIME...
LIKELY DUE IN PART TO WEAK MID LEVEL LAPSE RATES LESS THAN 6 C/KM.
BUT THE INCREASE IN MOISTURE AND WHAT WEAK LIFT THERE IS STILL SEEMS
TO SUPPORT CHANCE TO LOW-END LIKELY POPS SPREADING INTO AREAS WEST
OF HIGHWAY 1 LATE AFTERNOON AND THROUGH THE NIGHT. WILL ADJUST TO
BRING POPS EASTWARD A BIT LATER TO FIT WITH THE LATEST GUIDANCE
TIMING BUT WILL RETAIN THE GENERAL FLAVOR OF THE EARLIER FORECAST.
HIGHS 83-90... A LEAN TOWARD THE WARMER GFS-BASED STATISTICAL
GUIDANCE. ABOVE-GUIDANCE LOWS OF 68-72 WITHIN A PREFRONTAL WARM AIR
ADVECTION PATTERN. -GIH
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 245 AM FRIDAY...
FOR MONDAY/MONDAY NIGHT: BEST CHANCE OF SHOWERS/STORMS STILL LOOKS
TO BE IN THIS TIME FRAME. AS A STRONG VORTEX MOVES FROM SE ONTARIO
ACROSS SRN QUEBEC... THE WEAK SOUTHERN END OF THE TRAILING MID LEVEL
TROUGH EASES EASTWARD THROUGH THE AREA... ACCOMPANIED BY THE SURFACE
FRONT AND PRECEDED BY THE MINOR LOBE OF VORTICITY WHICH TRAVERSES
CENTRAL/ERN NC. THE ASCENT WILL BE ROOTED IN THE MID-UPPER LEVELS
WITH ONLY VERY WEAK MASS CONVERGENCE NEAR THE GROUND... BUT WITH
LIFT POTENTIALLY AUGMENTED BY 1000-1500 J/KG OF MLCAPE (FROM THE GFS
AND ECMWF)... IT SHOULD BE STRONG ENOUGH WITH THE EXPECTED DEEP
MOISTURE FOR LIKELY POPS AREAWIDE MONDAY... SLOWLY DECREASING WEST
TO EAST IN THE WEST MONDAY NIGHT BUT REMAINING LIKELY IN THE EAST.
CONFIDENCE IS HIGH THAT A PERIOD OF CATEGORICAL POPS WILL BE NEEDED
ONCE WE GET CLOSER AND CAN PIN DOWN TIMING A BIT BETTER. COULD SEE
UP TO AN INCH OF STORM-TOTAL RAIN BASED ON PRECIP WATER NEARING 2.0
INCHES AND A DEEP LCL-TO-0C LAYER AROUND 4 KM. HIGHS 77-84. LOWS
FROM 62 NW TO NEAR 70 SE.
FOR TUESDAY THROUGH THURSDAY: THE MID LEVEL SHEAR AXIS IS EXPECTED
TO SHIFT OFFSHORE BY TUESDAY MORNING WITH THE SURFACE FRONT DRIFTING
EASTWARD TO THE COASTAL AREA. THE ECMWF`S TROUGH IS NOTABLY WEAKER
AND MORE BAGGY THAN THE GFS`S... AND AS A RESULT THE ECMWF IS MUCH
SLOWER WITH THE FRONT... HANGING IT BACK FARTHER WEST... MEANING
CONTINUED WARM AIR/HIGH HUMIDITY AND RAIN CHANCES OVER ALL BUT THE
NW CWA. THINK THE ECMWF MAY BE ONTO SOMETHING GIVEN THAT THE
STRONGEST MID LEVEL FLOW WITH THE EASTERN CANADA LOW WILL HOLD NORTH
OF THE MASON-DIXON LINE. WILL HOLD ONTO AT LEAST CHANCE POPS FOR
SHOWERS SOUTH AND EAST OF RALEIGH THROUGH TUESDAY... WITH MORE
CLOUDS AND HIGHER DEW POINTS IN THE MID-UPPER 60S. THE QUEBEC VORTEX
LIFTS UP ACROSS ERN CANADA WHILE A SECOND LOW CROSSES THE DAKOTAS
TUESDAY NIGHT BEFORE SETTLING OVER THE UPPER MIDWEST THROUGH
MIDWEEK. FOR TUESDAY NIGHT THROUGH THURSDAY WE SHOULD BE UNDER THE
INFLUENCE OF THE CANADIAN SURFACE HIGH NOSING IN FROM THE NORTH
BENEATH WEAK MAINLY WESTERLY MID LEVEL FLOW... YIELDING FAIR SKIES
AND GENERALLY DRY CONDITIONS. THE RETURN EASTERLY FLOW AROUND THE
SURFACE HIGH STRENGTHENS BY THURSDAY WITH INCREASING ATLANTIC
INFLOW... AND THIS MAY RESULT IN A FEW SHOWERS OVER CENTRAL NC...
BUT THE CHANCE FOR SUFFICIENTLY DEEP MOISTURE IS TOO UNCERTAIN FOR
ANYTHING BUT SLIGHT CHANCE POPS FOR NOW. THICKNESSES SUPPORT TEMPS
NEAR NORMAL SE AND BELOW NORMAL NW ON TUESDAY... DROPPING TO ABOUT A
CATEGORY BELOW NORMAL FOR WEDNESDAY AND THURSDAY. -GIH
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 700 AM FRIDAY...
IFR/LIFR CONDITIONS ACROSS THE COASTAL PLAIN THIS MORNING HAS FOR
THE MOST REMAINED JUST TO THE EAST OF KRWI AND KFAY...THOUGH THE
STRATUS APPEARS TO ADVANCING NORTHWARD IN SOME AREAS. HAVE INCLUDED
A TEMPO AT THOSE SITES THROUGH 13Z. OTHERWISE...VFR CONDITIONS
SHOULD PREVAIL BY 14Z...WITH JUST A LIGHT SOUTHERLY WIND AND
SCATTERED CU THIS AFTERNOON. THERE IS A SMALL CHANCE OF A
SHOWER...MAINLY NEAR KFAY AFTER 18Z...AS THE SEABREEZE PUSHES
INLAND. EXPECT STRATUS AND FOG TO DEVELOP AGAIN TONIGHT BY BY
09Z...WITH THE HIGHEST CONFIDENCE FROM KRDU SOUTH AND EAST.
OUTLOOK...
VFR CONDITIONS ARE EXPECTED TO PREVAIL FOR MUCH OF THE
WEEKEND...WITH EARLY MORNING STRATUS/FOG POSSIBLE AGAIN SUNDAY. A
FEW ISOLATED SHOWERS/STORMS WILL BE POSSIBLE EACH AFTERNOON...MOSTLY
NEAR KFAY. MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE
ANTICIPATED ALONG AND AHEAD OF A COLD FRONT EXPECTED TO PROGRESS
SLOWLY EASTWARD THROUGH CENTRAL NC SUNDAY NIGHT THROUGH MONDAY NIGHT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT
SHORT TERM...SMITH/HARTFIELD
LONG TERM...HARTFIELD
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
956 PM EDT SAT JUN 1 2013
.SYNOPSIS...
WARM SECTOR THROUGH TONIGHT WITH CONVECTION POSSIBLE ESPECIALLY
LATE THIS AFTERNOON AND EVENING. COLD FRONT CROSSES SUNDAY INTO
MONDAY. COOLER AND DRIER TO START NEXT WEEK. WARM FRONT THURSDAY.
&&
.NEAR TERM /THROUGH SUNDAY/...
WITH LOSS OF SUNSHINE...LOW-LEVEL AIRMASS HAS BEGUN TO BECOME LESS
UNSTABLE. THIS HAS BEEN SEEN IN THE STORMS IN OUR REGION DECREASING
IN INTENSITY. HOWEVER...A LINE OF STORMS HAS DEVELOPED TO OUR WEST
AND NORTHWEST.
EXPECT THIS LINE WILL GRADUALLY MOVE EAST WITH TIME AND HAVE
ADJUSTED ONSET OF LIKELY AND HIGHER POPS TO REFLECT THIS THINKING.
OTHERWISE...ONLY TWEAKS MADE.
PREVIOUS DISCUSSION...
PRIMARY FORECAST CONCERN CONTINUES TO REVOLVE AROUND
SHOWERS/THUNDERSTORM CHANCES AS WELL AS POTENTIAL FOR SEVERE
WEATHER.
REGARDING THUNDERSTORMS THIS AFTERNOON/EVENING...15Z REGIONAL RADAR
IMAGERY AND SFC OBS CONTINUE TO SHOW ONGOING WIDESPREAD
PRECIP...MAINLY IN THE FORM OF SHOWERS...FROM WESTERN OHIO SW-WARD
DOWN THE EXTENT OF THE OHIO RIVER INTO WESTERN TENN/ARKANSAS
RESULTANT OF STRONG OVERNIGHT CONVECTION. SFC TEMPS IN WHAT APPEARED
YESTERDAY TO BE THE FAVORED AREAS OF THUNDERSTORMS AND SUBSEQUENT
SVR WX INITIATION STILL ONLY IN THE MID/UPPER 60S GENERALLY...WITH
NO LIGHTNING STRIKES CURRENTLY. SHOULD PRECIP/CLOUDS HANG ON OVER
THAT AREA...STRONGER STORMS MAY WAIT TO FORM FURTHER EAST OVER
CENTRAL OHIO AND POINTS SOUTHWEST WHERE SFC TEMPS HAVE WARMED TO THE
UPPER 70S/LOW 80S DESPITE FAIRLY DENSE HIGH CLOUD COVER. GOOD
DYNAMICS ARRIVE BY 21Z WHICH CONTINUE INTO THE
EVENING...PARTICULARLY OVER THE WESTERN ZONES WHERE 30-40KTS OF
SHEAR IN PLACE. WITH THE FRONT STILL WELL TO THE WEST
HOWEVER...TOUGH CALL ON DETERMINING A TRIGGERING MECHANISM. A VORT
MAX PER LATEST RUC13 PROGGED TO PUSH NE-WARD THROUGH CENTRAL KY BY
21Z-00Z MAY BE ENOUGH TO GET THINGS GOING. DO FEEL THAT
THUNDERSTORMS WILL SLOWLY BEGIN TO FORM BY THE MID/LATE AFTERNOON
HOURS AT FIRST RELATIVELY UNORGANIZED...WITH A GRADUAL INCREASE FROM
THE WEST BY AND AFTER 00Z SUN. AS USUAL...IT APPEARS TO BE A RACE
BETWEEN STORM DEVELOPMENT AND LOSS OF DAYTIME PEAK INSTABILITY. BUT
IN THE END...SOME STORMS MAY BECOME STRONG TO SEVERE MAINLY ACROSS
THE FAR WESTERN ZONES CLOSER TO THE OHIO RIVER BUT THE THREAT
APPEARS MARGINAL AT BEST. STRONG WINDS APPEAR TO BE THE MAIN HAZARD
WITH DCAPE VALS OVER 1K J/KG JUST TO THE SOUTHWEST OF THE FORECAST
AREA BUT EL/S ARE SUFFICIENTLY TALL FOR SOME LARGE HAIL.
LITTLE CHANGE FROM PREV FORECAST WITH REGARD TO THE REMAINDER OF THE
OVERNIGHT HOURS. A MORE GENERAL CONVECTIVE RAINFALL WITH SOME
THUNDER PERHAPS WILL PUSH INTO THE AREA WITH GOOD DEEP LAYER
MOISTURE AND A PREFRONTAL TROUGH-TYPE FEATURE. STILL EXPECTING
ROUGHLY A HALF-INCH OR SO ACROSS THE AREA...AND SOME LOCALIZED WATER
ISSUES COULD BE POSSIBLE SHOULD HEAVY SHOWERS/STORMS PASS OVER THE
SAME LOCATION BUT NOTHING WIDESPREAD EXPECTED. SUNDAY...AGAIN LITTLE
CHANGE FROM PREV FCST WITH THE MAIN AXIS OF DEEP MOISTURE PUSHING
ACROSS DURING THE MORNING HOURS WITH HIGH CHANCE POPS CONFINED
MAINLY TO CKB-CRW AND POINTS EAST BY 18Z. ACTUAL COLD FRONT HOWEVER
STILL LAGS WELL BEHIND AND ONLY ENTERING THE NW ZONES BY END OF THE
PERIOD. INHERITED MAX TEMPS AROUND 80 FOR LOWLANDS STILL LOOK ON
TRACK.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
GFS/ECMWF SHOW COLD FRONT OVER THE OH RIVER BY 00Z MONDAY. SHOWERS
AND STORMS WILL BE POSSIBLE ALONG THE FRONT...DIMINISHING IN
INTENSITY AND COVERAGE BY EARLY MONDAY MORNING.
THE FRONT BRINGS A WIND SHIFT FROM THE NORTHWEST ALOFT MONDAY
NIGHT...WHILE AT THE SFC COULD BECOME LIGHT AND VARIABLE...OR
CALM. THEN...FLOW BECOMES NORTHERLY LATER MONDAY AND MONDAY NIGHT
TO BRING COOLER TEMPERATURES...MILD AFTERNOON...AND RELATIVELY
COLDER NIGHTS ARE EXPECTED THROUGH TUESDAY NIGHT.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
WEAK SEMI ZONAL FLOW ALOFT AND NO VORT MAX FROM SHORTWAVES
SUGGEST BROAD HIGH PRESSURE WILL REMAIN IN CONTROL THROUGH EARLY
THURSDAY. THIS WILL CONTINUE TO CLEARING CONDITIONS...EXCEPT FOR
LOW LEVEL DIURNAL CU DURING THE AFTERNOON HOURS.
NEAR NORMAL TEMPERATURES EXPECTED THURSDAY ON. TWEAKED DOWN WPC
TEMPERATURE A BIT.
A WARM FRONTAL BOUNDARY FORMS ACROSS OH INTO SOUTHEAST OH
THURSDAY...UNDER SOUTHERLY FLOW. THE SOUTHERLY WINDS WILL ALSO
RESULT IN INCREASING LOW-LEVEL MOISTURE AND THE CHANCES FOR
SHOWERS AND STORMS...MAINLY DIURNAL IN NATURE...WILL ALSO RETURN
THROUGH THE REMAINDER OF THE PERIOD.
&&
.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
00Z SUNDAY THRU 00Z MONDAY...
BAND OF CONVECTION WELL AHEAD OF A COLD FRONT WILL SLOWLY MOVE
EASTWARD AND REACH THE OHIO RIVER BY 06Z SUNDAY...THE I79 CORRIDOR
BY 09Z...AND THE MOUNTAINS BY 12Z. OUTSIDE OF THIS RAIN...EXPECT
VFR CONDITIONS WILL PREVAIL. GENERALLY MVFR CONDITIONS IN THIS
RAIN...WITH AN EMBEDDED THUNDERSTORM POSSIBLE. WILL USE VCTS IN
TAFS.
THE SHOWERS AND THUNDERSTORMS SHOULD DECREASE FROM THE WEST AFTER
12Z...WITH ONLY A FEW STORMS EXPECTED ACROSS THE LOWLANDS AFTER 19Z.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z MONDAY...
FORECAST CONFIDENCE...MEDIUM.
ALTERNATE SCENARIOS: TIMING OF BAND OF CONVECTION LATER PART OF
PERIOD MAY 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 SUN 06/02/13
UTC 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
EDT 1HRLY 22 23 00 01 02 03 04 05 06 07 08 09
CRW CONSISTENCY H H H H H H H H H M M M
HTS CONSISTENCY H H H H H H M M M M M M
BKW CONSISTENCY H H H H H H H H H M M M
EKN CONSISTENCY H H H H H H H H H M M M
PKB CONSISTENCY H H H H H H H M M M M M
CKB CONSISTENCY H H H H H H H H H M M M
AFTER 00Z MONDAY...
IFR POSSIBLE IN SHOWERS AND THUNDERSTORMS SUNDAY NIGHT...AND IN
POST-RAIN FOG SUNDAY NIGHT INTO MONDAY MORNING.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JMV/26
NEAR TERM...JSH/50
SHORT TERM...ARJ
LONG TERM...ARJ
AVIATION...JSH
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
810 PM EDT SAT JUN 1 2013
.SYNOPSIS...
WEATHER SYSTEM OVER THE WESTERN GREAT LAKES WILL SHIFT EASTWARD
TONIGHT...DRAGGING A COLD FRONT THROUGH THE OHIO VALLEY LATER
TONIGHT AND SUNDAY. THIS WILL PROMPT SEVERAL ROUNDS OF SHOWERS AND
STORMS FOR THE AREA...BEFORE A DRYING TREND TAKES HOLD FOR SUNDAY
NIGHT...LASTING INTO THE MIDDLE OF NEXT WEEK. A COOLER AND DRIER
AIRMASS WILL DOMINATE THROUGH THIS TIME PERIOD.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
STILL WORKING SOME DECENT UPDRAFTS NORTHEAST THROUGH SOUTH-CENTRAL
OHIO AND NORTHEAST KENTUCKY. A FEW STORM SPLITS...LEFT MOVING HAIL
CORES...AND PERSISTENT WEAK/BROAD ROTATION HAVE BEEN NOTED WITH
THE STRONGEST STORMS /PROMPTED ONE QUICK WARNING/. THESE WILL
CONTINUE TO WORK RATHER BRISKLY OFF TO THE NORTHEAST AND WHILE A
ROGUE SMALL HAIL/WIND GUST IS POSSIBLE...THINK THESE HAVE WEAKENED
IN A GENERAL SENSE FOR THE EVENING.
ATTENTION THEN TURNS TO THE STRONGER SYNOPTIC FORCING ENTERING
CNTL/ERN IL CURRENTLY WITH AN ATTENDANT COLD FRONT. RECENT HRRR
RUNS SIMPLY ADAMANT A WHOLE BUNCH OF SHOWERS/STORMS WILL DEVELOP
ACROSS EASTERN IND/WRN OHIO IN A FEW HOURS...AND DON/T WANT TO
TOTALLY DISCOUNT THIS AS IT HAS BEEN ONE OF THE FEW STEADIER
SIGNALS IN THE HRRR THE LAST FEW HOURS. BUT LAST GLIMPSES OF
SATELLITE VIS PICS OVER IND SHOW THAT THE STABLE AIRMASS IS INTACT
AND VERY FEW AGITATED CUMULUS/ACCAS ARE EVIDENT. THERE SHOULD BE A
MODEST RAMP-UP OF THE LOW LEVEL JET IMMEDIATELY DOWNSTREAM OF THE
PV ANOMALY ROTATING THROUGH IL RIGHT NOW SO THE SYNOPTIC SIGNALS
SAY TO STAY THE COURSE WITH HIGHER RAIN/STORM CHANCES BEGINNING
VERY LATE THIS EVENING. EARLY LOOK AT THE 02.00Z KILN BALLOON DATA
SUGGESTS INSTBY IS NOT IMPRESSIVE BUT WINDS/SHEAR CONTINUE TO BE
FAVORABLE FOR STORM ORGANIZATION. HOWEVER...SPC MESOA DATA
SUGGESTING THE DCAPE POOL HAS BEEN MODIFIED SOME AND NOW THE NEAR
SFC SHALLOW INVERSION HAS BEGUN TO FORM PER OBS. SO WHILE A FEW
SEVERE REPORTS ARE POSSIBLE OVERNIGHT...JUST NOT SEEING A GREAT
SETUP AND THUS WILL TONE BACK HAZ WX OUTLOOK FOR THE OVERNIGHT
PERIOD.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/...
SECONDARY WAVE ALOFT FINALLY ESCORTS THE TROUGH AXIS OUT OF THE
AREA TOMORROW AND THIS ALLOWS A WEAK SECONDARY FRONT TO DEVELOP
AND PUSH THROUGH DURING THE DAY. MAY BE A BROKEN BAND OF SHOWERS
ALONG THIS FEATURE BY MID AFTERNOON...SO CARRIED THIS CHANCE FROM
NW-SE ACROSS THE AREA DURING THE LATE MORNING INTO THE EARLY
EVENING. MUCH COOLER/DRIER AIRMASS ARRIVES ON THE HEELS OF THIS
FRONT AND MAKES FOR A COMFORTABLE SUNDAY NIGHT WITH LOWS DOWN INTO
THE 50S UNDER CLEARING SKIES.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
PERIOD BEGINS WITH HIGH PRESSURE CENTERED OVER THE UPPER MS VALLEY.
THE HIGH WILL BUILD SE INTO THE LOWER GREAT LAKES THROUGH TUESDAY.
HIGHS ON MONDAY WILL BE COOL...RANGING FROM THE UPPER 60S TO THE
LOWER 70S WHICH WILL BE ABOUT 5 TO 10 DEGREES BELOW NORMAL FOR EARLY
JUNE. TEMPERATURES WILL FALL INTO THE UPPER 40S TO LOWER 50S MONDAY
NIGHT. 12Z MODELS HAVE COME IN A LITTLE WARMER FOR TUESDAY. SO TOOK
A CONSENSUS FORECAST AND RAISED HIGHS FOR TUESDAY INTO THE LOWER TO
MID 70S.
ON WEDNESDAY THE SFC HIGH PRESSURE IS FORECAST TO SLIDE EAST. THE
ECMWF IS THE QUICKEST WITH THE RETURN PCPN...BUT THE REMAINING
MODELS KEEP THE FA DRY...SO LEANED TOWARDS THE MAJORITY.
WEDNESDAY NIGHT INTO THURSDAY AS WRMFNT DEVELOPS OVER THE OH VLY...
ATMOSPHERE BECOMES UNTIL STABLE AND IT LOOKS LIKE THERE WILL BE A
CHANCE OF SCT TSRA. THU NGT INTO FRI...H5 WAVE SWINGS UP THE OH VLY
ADDING EXTRA LIFT AND IT DRIVES A CDFNT ACROSS THE REGION KEEPING
CHC OF CONVECTION IN THE FORECAST. DRIER AIR TRIES TO BUILD IN FOR
SATURDAY.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
CONVECTIVE MODELS WERE ALL INDICATING DEVELOPMENT OF SHRA/TSRA
AHEAD OF IMMEDIATE PREFRONTAL ACTIVITY CURRENTLY OVER IL. SOME
MODELS STILL BRINGING THIS SOLUTION...BUT ANY ACTIVITY SHOULD BE
WIDELY SCATTERED UNTIL THE MAIN LINE OF SHOWERS WITH EMBEDDED
THUNDERSTORMS MAKING AN APPEARANCE AFTER 04Z. HIGH WIND THREAT
DIMINISHED SO KEEPING WIND GUSTS MARGINAL. STILL POTENTIAL FOR
SOME MVFR VSBYS WHERE EMBEDDED HEAVY RAIN OCCURS...WITH THE BEST
POTENTIAL IN THE WEST BETWEEN 05-08Z AND 07-11Z IN THE EAST.
CONVECTION OVER SOUTH CENTRAL OHIO WILL APPROACH KLCK/KCMH NEAR
02Z...BUT EXPECTATION IS FOR THE BEST ACTIVITY TO BE JUST EAST OF
THE TERMINAL SITES.
MVFR CIGS WITH THE PREFRONTAL ACTIVITY AS WELL AS WITH LINGERING
SHRA AFTER 12Z SUN BEFORE LIFTING NEAR 00Z.
OUTLOOK...NO SIGNIFICANT WEATHER EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...BINAU
NEAR TERM...BINAU
SHORT TERM...BINAU
LONG TERM...SITES
AVIATION...JDR
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
757 PM EDT SAT JUN 1 2013
.SYNOPSIS...
WEATHER SYSTEM OVER THE WESTERN GREAT LAKES WILL SHIFT EASTWARD
TONIGHT...DRAGGING A COLD FRONT THROUGH THE OHIO VALLEY LATER
TONIGHT AND SUNDAY. THIS WILL PROMPT SEVERAL ROUNDS OF SHOWERS AND
STORMS FOR THE AREA...BEFORE A DRYING TREND TAKES HOLD FOR SUNDAY
NIGHT...LASTING INTO THE MIDDLE OF NEXT WEEK. A COOLER AND DRIER
AIRMASS WILL DOMINATE THROUGH THIS TIME PERIOD.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
STILL WORKING SOME DECENT UPDRAFTS NORTHEAST THROUGH SOUTH-CENTRAL
OHIO AND NORTHEAST KENTUCKY. A FEW STORM SPLITS...LEFT MOVING HAIL
CORES...AND PERSISTENT WEAK/BROAD ROTATION HAVE BEEN NOTED WITH
THE STRONGEST STORMS /PROMPTED ONE QUICK WARNING/. THESE WILL
CONTINUE TO WORK RATHER BRISKLY OFF TO THE NORTHEAST AND WHILE A
ROGUE SMALL HAIL/WIND GUST IS POSSIBLE...THINK THESE HAVE WEAKENED
IN A GENERAL SENSE FOR THE EVENING.
ATTENTION THEN TURNS TO THE STRONGER SYNOPTIC FORCING ENTERING
CNTL/ERN IL CURRENTLY WITH AN ATTENDANT COLD FRONT. RECENT HRRR
RUNS SIMPLY ADAMANT A WHOLE BUNCH OF SHOWERS/STORMS WILL DEVELOP
ACROSS EASTERN IND/WRN OHIO IN A FEW HOURS...AND DON/T WANT TO
TOTALLY DISCOUNT THIS AS IT HAS BEEN ONE OF THE FEW STEADIER
SIGNALS IN THE HRRR THE LAST FEW HOURS. BUT LAST GLIMPSES OF
SATELLITE VIS PICS OVER IND SHOW THAT THE STABLE AIRMASS IS INTACT
AND VERY FEW AGITATED CUMULUS/ACCAS ARE EVIDENT. THERE SHOULD BE A
MODEST RAMP-UP OF THE LOW LEVEL JET IMMEDIATELY DOWNSTREAM OF THE
PV ANOMALY ROTATING THROUGH IL RIGHT NOW SO THE SYNOPTIC SIGNALS
SAY TO STAY THE COURSE WITH HIGHER RAIN/STORM CHANCES BEGINNING
VERY LATE THIS EVENING. EARLY LOOK AT THE 02.00Z KILN BALLOON DATA
SUGGESTS INSTBY IS NOT IMPRESSIVE BUT WINDS/SHEAR CONTINUE TO BE
FAVORABLE FOR STORM ORGANIZATION. HOWEVER...SPC MESOA DATA
SUGGESTING THE DCAPE POOL HAS BEEN MODIFIED SOME AND NOW THE NEAR
SFC SHALLOW INVERSION HAS BEGUN TO FORM PER OBS. SO WHILE A FEW
SEVERE REPORTS ARE POSSIBLE OVERNIGHT...JUST NOT SEEING A GREAT
SETUP AND THUS WILL TONE BACK HAZ WX OUTLOOK FOR THE OVERNIGHT
PERIOD.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/...
SECONDARY WAVE ALOFT FINALLY ESCORTS THE TROUGH AXIS OUT OF THE
AREA TOMORROW AND THIS ALLOWS A WEAK SECONDARY FRONT TO DEVELOP
AND PUSH THROUGH DURING THE DAY. MAY BE A BROKEN BAND OF SHOWERS
ALONG THIS FEATURE BY MID AFTERNOON...SO CARRIED THIS CHANCE FROM
NW-SE ACROSS THE AREA DURING THE LATE MORNING INTO THE EARLY
EVENING. MUCH COOLER/DRIER AIRMASS ARRIVES ON THE HEELS OF THIS
FRONT AND MAKES FOR A COMFORTABLE SUNDAY NIGHT WITH LOWS DOWN INTO
THE 50S UNDER CLEARING SKIES.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
PERIOD BEGINS WITH HIGH PRESSURE CENTERED OVER THE UPPER MS VALLEY.
THE HIGH WILL BUILD SE INTO THE LOWER GREAT LAKES THROUGH TUESDAY.
HIGHS ON MONDAY WILL BE COOL...RANGING FROM THE UPPER 60S TO THE
LOWER 70S WHICH WILL BE ABOUT 5 TO 10 DEGREES BELOW NORMAL FOR EARLY
JUNE. TEMPERATURES WILL FALL INTO THE UPPER 40S TO LOWER 50S MONDAY
NIGHT. 12Z MODELS HAVE COME IN A LITTLE WARMER FOR TUESDAY. SO TOOK
A CONSENSUS FORECAST AND RAISED HIGHS FOR TUESDAY INTO THE LOWER TO
MID 70S.
ON WEDNESDAY THE SFC HIGH PRESSURE IS FORECAST TO SLIDE EAST. THE
ECMWF IS THE QUICKEST WITH THE RETURN PCPN...BUT THE REMAINING
MODELS KEEP THE FA DRY...SO LEANED TOWARDS THE MAJORITY.
WEDNESDAY NIGHT INTO THURSDAY AS WRMFNT DEVELOPS OVER THE OH VLY...
ATMOSPHERE BECOMES UNTIL STABLE AND IT LOOKS LIKE THERE WILL BE A
CHANCE OF SCT TSRA. THU NGT INTO FRI...H5 WAVE SWINGS UP THE OH VLY
ADDING EXTRA LIFT AND IT DRIVES A CDFNT ACROSS THE REGION KEEPING
CHC OF CONVECTION IN THE FORECAST. DRIER AIR TRIES TO BUILD IN FOR
SATURDAY.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
SOUTHWEST WINDS WILL CONTINUE TO GUST AROUND 20-25 KTS THIS
AFTERNOON. STILL A STUBBORN MID TO HIGH CLOUD DECK OVER MOST OF THE
AREA ALTHOUGH SCT LIGHT SHOWERS ARE COMING TO AN END. WATCHING FOR
POSSIBLE REDEVELOPMENT OF SHOWERS AND THUNDERSTORMS LATER THIS
AFTERNOON. IF THIS MATERIALIZES...AND CONFIDENCE IS NOT
PARTICULARLY HIGH BASED ON LATEST HIGH RESOLUTION MODEL
SOLUTIONS...THINKING THE BEST CHANCE WOULD BE AROUND THE EASTERN
TAF SITES AS THAT AREA HAS SEEN THE MOST DAYTIME HEATING SO FAR.
BETTER CHANCE FOR SHOWERS AND STORMS FOR ALL TAF SITES WILL COME
LATE THIS AFTERNOON AND EVENING AS A COLD FRONT APPROACHES FROM
THE WEST. THIS ACTIVITY WILL SPREAD FROM WEST TO EAST WITH THE
POSSIBILITY OF A FEW STRONG TO SEVERE STORMS CONTAINING BRIEF YET
STRONG SHIFTING WINDS AS THEY PASS. MVFR/IFR CIGS AND VSBYS WILL
BE POSSIBLE WITH ANY STORMS LATE THIS AFTERNOON AND EVENING.
CIGS WILL LIKELY REMAIN MVFR LATE TONIGHT AND SOME LINGERING
SHOWERS WILL BE POSSIBLE AS THE COLD FRONT MOVES ACROSS THE AREA.
EXPECT A GRADUAL RETURN TO VFR CIGS SUNDAY MORNING.
OUTLOOK...NO SIGNIFICANT WEATHER EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...BINAU
NEAR TERM...BINAU
SHORT TERM...BINAU
LONG TERM...SITES
AVIATION...KURZ
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
723 PM EDT SAT JUN 1 2013
.SYNOPSIS...
WARM SECTOR THROUGH TONIGHT WITH CONVECTION POSSIBLE ESPECIALLY
LATE THIS AFTERNOON AND EVENING. COLD FRONT CROSSES SUNDAY INTO
MONDAY. COOLER AND DRIER TO START NEXT WEEK. WARM FRONT THURSDAY.
&&
.NEAR TERM /THROUGH SUNDAY/...
PRIMARY FORECAST CONCERN CONTINUES TO REVOLVE AROUND
SHOWERS/THUNDERSTORM CHANCES AS WELL AS POTENTIAL FOR SEVERE
WEATHER.
REGARDING THUNDERSTORMS THIS AFTERNOON/EVENING...15Z REGIONAL RADAR
IMAGERY AND SFC OBS CONTINUE TO SHOW ONGOING WIDESPREAD
PRECIP...MAINLY IN THE FORM OF SHOWERS...FROM WESTERN OHIO SW-WARD
DOWN THE EXTENT OF THE OHIO RIVER INTO WESTERN TENN/ARKANSAS
RESULTANT OF STRONG OVERNIGHT CONVECTION. SFC TEMPS IN WHAT APPEARED
YESTERDAY TO BE THE FAVORED AREAS OF THUNDERSTORMS AND SUBSEQUENT
SVR WX INITIATION STILL ONLY IN THE MID/UPPER 60S GENERALLY...WITH
NO LIGHTNING STRIKES CURRENTLY. SHOULD PRECIP/CLOUDS HANG ON OVER
THAT AREA...STRONGER STORMS MAY WAIT TO FORM FURTHER EAST OVER
CENTRAL OHIO AND POINTS SOUTHWEST WHERE SFC TEMPS HAVE WARMED TO THE
UPPER 70S/LOW 80S DESPITE FAIRLY DENSE HIGH CLOUD COVER. GOOD
DYNAMICS ARRIVE BY 21Z WHICH CONTINUE INTO THE
EVENING...PARTICULARLY OVER THE WESTERN ZONES WHERE 30-40KTS OF
SHEAR IN PLACE. WITH THE FRONT STILL WELL TO THE WEST
HOWEVER...TOUGH CALL ON DETERMINING A TRIGGERING MECHANISM. A VORT
MAX PER LATEST RUC13 PROGGED TO PUSH NE-WARD THROUGH CENTRAL KY BY
21Z-00Z MAY BE ENOUGH TO GET THINGS GOING. DO FEEL THAT
THUNDERSTORMS WILL SLOWLY BEGIN TO FORM BY THE MID/LATE AFTERNOON
HOURS AT FIRST RELATIVELY UNORGANIZED...WITH A GRADUAL INCREASE FROM
THE WEST BY AND AFTER 00Z SUN. AS USUAL...IT APPEARS TO BE A RACE
BETWEEN STORM DEVELOPMENT AND LOSS OF DAYTIME PEAK INSTABILITY. BUT
IN THE END...SOME STORMS MAY BECOME STRONG TO SEVERE MAINLY ACROSS
THE FAR WESTERN ZONES CLOSER TO THE OHIO RIVER BUT THE THREAT
APPEARS MARGINAL AT BEST. STRONG WINDS APPEAR TO BE THE MAIN HAZARD
WITH DCAPE VALS OVER 1K J/KG JUST TO THE SOUTHWEST OF THE FORECAST
AREA BUT EL/S ARE SUFFICIENTLY TALL FOR SOME LARGE HAIL.
LITTLE CHANGE FROM PREV FORECAST WITH REGARD TO THE REMAINDER OF THE
OVERNIGHT HOURS. A MORE GENERAL CONVECTIVE RAINFALL WITH SOME
THUNDER PERHAPS WILL PUSH INTO THE AREA WITH GOOD DEEP LAYER
MOISTURE AND A PREFRONTAL TROUGH-TYPE FEATURE. STILL EXPECTING
ROUGHLY A HALF-INCH OR SO ACROSS THE AREA...AND SOME LOCALIZED WATER
ISSUES COULD BE POSSIBLE SHOULD HEAVY SHOWERS/STORMS PASS OVER THE
SAME LOCATION BUT NOTHING WIDESPREAD EXPECTED. SUNDAY...AGAIN LITTLE
CHANGE FROM PREV FCST WITH THE MAIN AXIS OF DEEP MOISTURE PUSHING
ACROSS DURING THE MORNING HOURS WITH HIGH CHANCE POPS CONFINED
MAINLY TO CKB-CRW AND POINTS EAST BY 18Z. ACTUAL COLD FRONT HOWEVER
STILL LAGS WELL BEHIND AND ONLY ENTERING THE NW ZONES BY END OF THE
PERIOD. INHERITED MAX TEMPS AROUND 80 FOR LOWLANDS STILL LOOK ON
TRACK.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
GFS/ECMWF SHOW COLD FRONT OVER THE OH RIVER BY 00Z MONDAY. SHOWERS
AND STORMS WILL BE POSSIBLE ALONG THE FRONT...DIMINISHING IN
INTENSITY AND COVERAGE BY EARLY MONDAY MORNING.
THE FRONT BRINGS A WIND SHIFT FROM THE NORTHWEST ALOFT MONDAY
NIGHT...WHILE AT THE SFC COULD BECOME LIGHT AND VARIABLE...OR
CALM. THEN...FLOW BECOMES NORTHERLY LATER MONDAY AND MONDAY NIGHT
TO BRING COOLER TEMPERATURES...MILD AFTERNOON...AND RELATIVELY
COLDER NIGHTS ARE EXPECTED THROUGH TUESDAY NIGHT.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
WEAK SEMI ZONAL FLOW ALOFT AND NO VORT MAX FROM SHORTWAVES
SUGGEST BROAD HIGH PRESSURE WILL REMAIN IN CONTROL THROUGH EARLY
THURSDAY. THIS WILL CONTINUE TO CLEARING CONDITIONS...EXCEPT FOR
LOW LEVEL DIURNAL CU DURING THE AFTERNOON HOURS.
NEAR NORMAL TEMPERATURES EXPECTED THURSDAY ON. TWEAKED DOWN WPC
TEMPERATURE A BIT.
A WARM FRONTAL BOUNDARY FORMS ACROSS OH INTO SOUTHEAST OH
THURSDAY...UNDER SOUTHERLY FLOW. THE SOUTHERLY WINDS WILL ALSO
RESULT IN INCREASING LOW-LEVEL MOISTURE AND THE CHANCES FOR
SHOWERS AND STORMS...MAINLY DIURNAL IN NATURE...WILL ALSO RETURN
THROUGH THE REMAINDER OF THE PERIOD.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
00Z SUNDAY THRU 00Z MONDAY...
BAND OF CONVECTION WELL AHEAD OF A COLD FRONT WILL SLOWLY MOVE
EASTWARD AND REACH THE OHIO RIVER BY 06Z SUNDAY...THE I79 CORRIDOR
BY 09Z...AND THE MOUNTAINS BY 12Z. OUTSIDE OF THIS RAIN...EXPECT
VFR CONDITIONS WILL PREVAIL. GENERALLY MVFR CONDITIONS IN THIS
RAIN...WITH AN EMBEDDED THUNDERSTORM POSSIBLE. WILL USE VCTS IN
TAFS.
THE SHOWERS AND THUNDERSTORMS SHOULD DECREASE FROM THE WEST AFTER
12Z...WITH ONLY A FEW STORMS EXPECTED ACROSS THE LOWLANDS AFTER 19Z.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z MONDAY...
FORECAST CONFIDENCE...MEDIUM.
ALTERNATE SCENARIOS: TIMING OF BAND OF CONVECTION LATER PART OF
PERIOD MAY 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 SUN 06/02/13
UTC 1HRLY 00 01 02 03 04 05 06 07 08 09 10 11
EDT 1HRLY 20 21 22 23 00 01 02 03 04 05 06 07
CRW CONSISTENCY H H H H H H H H H H H M
HTS CONSISTENCY H H H H H H H H M M M M
BKW CONSISTENCY H H H H H H H H H H H M
EKN CONSISTENCY H H H H H H H H H H H M
PKB CONSISTENCY H H H H H H H H H M M M
CKB CONSISTENCY H H H H H H H H H H H M
AFTER 00Z MONDAY...
IFR POSSIBLE IN SHOWERS AND THUNDERSTORMS SUNDAY NIGHT...AND IN
POST-RAIN FOG SUNDAY NIGHT INTO MONDAY MORNING.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JMV/26
NEAR TERM...50
SHORT TERM...ARJ
LONG TERM...ARJ
AVIATION...JSH
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
256 PM EDT FRI MAY 31 2013
.SYNOPSIS...
WARM SECTOR THROUGH SATURDAY NIGHT WITH CONVECTION POSSIBLE
ESPECIALLY DURING DAYTIME HEATING HOURS. COLD FRONT CROSSES
SUNDAY. COOLER AND DRIER TO START NEXT WEEK.
&&
.NEAR TERM /THROUGH SATURDAY/...
18Z RADAR IMAGERY SHOWING SHOWERS AND THUNDERSTORMS CONTINUING TO
DEVELOP TO THE WEST ROUGHLY AROUND THE IN/OH BORDER AREA SOUTHWARD
INTO CENTRAL KENTUCKY. OUT AHEAD OF THAT GENERAL AREA A FEW DISCRETE
THUNDERSTORMS HAD FORMED TO THE EAST. PRIMARY CONCERNS IN THE NEAR
TERM REVOLVE AROUND THIS EVENING/S CONVECTION AS WELL AS
REDEVELOPING SHOWERS/THUNDERSTORMS TOMORROW.
THIS EVENING...TOUGH CALL ON EXACTLY HOW FAR EAST TO TAKE PRECIP
WITH A READILY-APPARENT DECAYING MCV PUSHING E/NE-WARD ACROSS NORTH
CENTRAL KY. LATEST RAP SEEMS TO HAVE SOMEWHAT OF A HANDLE ON THE
SHEAR ASSOC WITH IT...WITH NEAR 40KTS OF SHEAR DEPICTED ACROSS THE
SW OHIO AND NC KY AREAS. FURTHER EAST OVER OUR WESTERN ZONES...SHEAR
IS APPRECIABLY LOWER AND ONLY AROUND 15-20KTS. LATEST RAP RUNS ALSO
CONTINUE TO WEAKEN/SHEAR THE VORT MAX ASSOC WITH THE MCV...WITH
SHEAR VALUES ONLY CLIMBING TO AROUND 25KTS NEAR PERRY CO OH...AND
LESS POINTS EAST AND SOUTH OF THAT...BY 00Z. INSTABILITY WILL BE
DECREASING AS WELL AND BECOMING MORE ELEVATED AS USUAL...WHICH
SHOULD SPELL A DECREASING RISK OF STRONG WINDS. ALL IN ALL...DO
BELIEVE SHOWERS AND SOME THUNDERSTORMS STAND A DECENT CHANCE OF
REACHING OUR WESTERN ZONES AND PARTICULARLY THE SE OHIO ZONES. WHILE
A SEVERE THUNDERSTORM CAN/T BE COMPLETELY RULED OUT IN THOSE
LOCATIONS...CURRENT THINKING IS THAT THE BULK OF ANY SEVERE WX
REMAINS WEST.
OVERNIGHT...WILL KEEP GENERAL INHERITED FORECAST AND DRY OUT MOST
LOCATIONS BTWN 03Z-06Z. DID ELECT TO KEEP A SLIGHT CHANCE ACROSS THE
FAR NW ZONES HOWEVER...ON THE NOSE OF A 850MB JET. PREV FCST LOW
TEMPS IN THE MID/UPPER 60S LOWLANDS STILL LOOK GOOD. SLIGHTLY
STRONGER BL WINDS OVERNIGHT PROGGED AFTER 06Z SHOULD PRECLUDE
WIDESPREAD FOG FORMATION BUT THE USUAL SPOTS SUCH AS EKN WILL MOST
LIKELY SEE REDUCED VIS NEAR DAWN.
TOMORROW...INHERITED MAX TEMPS IN THE MID/UPPER 80S LOWLANDS LOOK
GOOD. PRIMARY FOCUS ON THUNDERSTORMS AND SVR THUNDERSTORM POTENTIAL.
NOT REALLY SEEING MUCH IN THE WAY OF ANY ORGANIZED LARGE-SCALE LIFT
FOR MUCH OF THE DAY WITH THE TROUGH AXIS AND SFC COLD FRONT STILL
WELL TO THE WEST. LOWERED POPS TO LOW CHANCE FOR THE MORNING HOURS
AND INTO THE EARLY AFTERNOON HOURS AS SUCH. BTWN 18Z-21Z...GOOD
DYNAMICS ARRIVE TO THE WEST OF OUR AREA...OVER IN/WEST OH SOUTHWARD
INTO CENTRAL KY. THIS AREA SHOULD SERVE FOR ORGANIZED CONVECTIVE
INITIATION BY 21Z...WITH SUPERCELLS A POSSIBILITY. THIS AREA WILL
SLOWLY PROGRESS EASTWARD...BUT RIGHT-MOVER MOTION WOULD TAKE THESE
STORMS IN AN MORE E/NE DIRECTION AROUND 30KTS. AGAIN AS WITH THIS
AFTERNOON...THE BULK OF SVR WX SHOULD REMAIN WEST BUT WITH BETTER
SHEAR OVER OUR AREA TOMORROW A BETTER LIKELIHOOD OF SVR WX OVER OUR
WESTERN ZONES EXISTS PRIMARILY LATE AFTERNOON INTO MID-EVE HOURS.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
COLD FRONT WILL PUSH EAST INTO THE CWA SUNDAY MORNING. TIMING OF THE
FRONT LOOKS TO BE A FEW HOURS SLOWER THAN PREVIOUS RUNS...BUT STILL
THINKING MUCH OF THE CWA WILL NOT SEE MUCH IN TERMS OF SEVERE DUE TO
TIMING...ALTHOUGH THE EASTERN ZONES WILL BE MORE SUSCEPTIBLE DUE TO
LATER FRONTAL PASSAGE. DECENT CAPE...GENERALLY 1500-2000
J/KG...ALONG WITH 30-40 KTS 0-6KM BULK SHEAR WILL CREATE A POTENTIAL
FOR STRONG STORMS...WITH WINDS...AND HAIL THE PRIMARY
THREATS...MAINLY ACROSS THE EAST. HOWEVER...PLENTY OF CLOUD COVER
OUT AHEAD OF THE FRONT MAY ALSO HELP TO MITIGATE THE SEVERE
THREAT...ESPECIALLY EARLY ON. SO FOR NOW...ITS A WAIT AND SEE
SCENARIO TO SEE IF ANY OF THE ABOVE MENTIONED FACTORS ARE ABLE TO
LINE UP...BUT LOOKING LIKE BULK OF SEVERE THREAT WILL BE TO THE EAST
OF THE CWA. AS OF RIGHT NOW...SPC HAS THE SLIGHT RISK TO THE EAST OF
THE CWA...WITH CWA IN GENERAL THUNDER...AND A 5 PERCENT PROB OUTLOOK
FOR SEVERE.
COLD FRONT WILL EXIT TO THE EAST OF THE CWA SUNDAY NIGHT...WITH
COOLER AND DRIER WEATHER TAKING HOLD.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
GENERALLY FOLLOWED WPC THINKING WITH SOME TWEAKS.
HIGH PRESSURE WILL DOMINATE THE REGION ON TUESDAY...WITH
TEMPERATURES NEAR NORMAL READINGS. HOWEVER...THE HIGH WILL PUSH
EAST ON WEDNESDAY...RESULTING IN SOUTHERLY WINDS AND WARMER
TEMPERATURES. THE SOUTHERLY WINDS WILL ALSO RESULT IN INCREASING
LOW-LEVEL MOISTURE AND THE CHANCES FOR SHOWERS AND STORMS...MAINLY
DIURNAL IN NATURE...WILL ALSO RETURN THROUGH THE REMAINDER OF THE
PERIOD.
&&
.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
12Z FRIDAY THRU 12Z SATURDAY...
VFR FOR MOST SITES THROUGH MUCH OF THE PERIOD. PUT IN SOME RIVER
AND VALLEY FOG THAT WILL RESULT IN SOME MVFR CONDITIONS FOR THE
VALLEYS OVERNIGHT. EKN IS EXPECTED TO DROP TO IFR FOR AT LEAST A FEW HOURS
WITH CALM WINDS AND HIGHER RH IN THE SHELTERED VALLEY.
TOWARD THE END OF THE PERIOD...CIGS ARE EXPECTED TO LOWER AS PRECIP
BEGINS TO MOVE INTO SE OH AND NORTHERN WV...HOWEVER...GENERALLY
EXPECT VFR CONDITIONS TO REMAIN.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z SATURDAY...
FORECAST CONFIDENCE...HIGH.
ALTERNATE SCENARIOS: SUB-VFR VIS OVERNIGHT MAY VARY IN EXPECTED
COVERAGE AND/OR INTENSITY. TIMING AND COVERAGE OF SHOWERS AND
THUNDERSTORMS MAY 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 18 19 20 21 22 23 00 01 02 03 04 05
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
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 H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H M M
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 18Z SATURDAY...
IFR POSSIBLE IN SHOWERS AND THUNDERSTORMS SUNDAY INTO SUNDAY
NIGHT...AND POST RAIN...FOG...AND LOW CLOUDS LATE SUNDAY NIGHT
INTO MONDAY MORNING.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JSH/50/SL
NEAR TERM...50
SHORT TERM...SL
LONG TERM...JSH
AVIATION...LS
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1112 PM EDT SAT JUN 1 2013
.SYNOPSIS...
A STRONG RIDGE AND RELATIVELY WARM MOIST AIR OVER OUR REGION WILL
BE DISPLACED BY A FRONTAL SYSTEM SUNDAY. BEHIND THE FRONT AND OVER
THE COMING WEEK A TROUGH WILL DOMINATE OUR REGION WITH GENERALLY
COOLER AND DRIER AIR PREVAILING. OUR BEST CHANCE OF SHOWERS AND
THUNDERSTORMS WILL BE AHEAD OF THE FRONTAL SYSTEM SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
FOR THE OVERNIGHT...LOOKING UPSTREAM...LAKE BREEZE INTERACTION
WITH GREATER MOISTURE AND INSTABILITY CONTS TO YIELED SCATTERED
STORMS FROM EASTERN OHIO TO THE IMMEDIATE LAKE ERIE AND LAKE
ONTARIO SHORELINES. PREVAILING SOUTHERLY COMPONENT HAS BEEN STRONG
ENOUGH TO PREVENT ANY EASTWARD DRIFT OF THE THE BOUNDARY THUS
FAR...SPARING MY NORTHWEST COUNTIES.
LATEST RAP INDICATES THAT WILL CONTINUE TO BE THE CASE FOR THE
REST OF THE EVENING...WITH POPS RAMPING UP AFTER MIDNIGHT AND
INCREASING FROM WEST TO EAST THEREAFTER. THIS ACTIVITY COMES
ALONG THE LEADING EDGE OF A STRENGTHENING 40-50KT 850 MB JET AND
ANOMALOUS BUT FAIRLY NARROW PLUME OF DEEPER LAYER MOISTURE (~1.65"
PW) TRACKING TO THE ALLEGHENY FRONT BY 12Z SUN. SO... WILL KEEP
POPS UP ALONG MY WESTERN AND NORTHWESTERN BORDERS OVERNIGHT. AS
PREVIOUSLY MENTIONED...POTENTIAL FOR SOME HEAVIER DOWNPOURS AS
PWATS REMAIN ABOVE NORMAL.
TEMPS REMAIN MILD OVERNIGHT IN SW FLOW...WITH HUMID LOWS ONLY
FALLING INTO THE 60S.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
AN APPROACHING COLD FRONT WILL BRING MORE WIDESPREAD SHOWERS AND
THUNDERSTORMS ON SUNDAY...EARLIER IN THE WEST AND FROM MIDDAY ON IN
THE EAST. WE COULD BE DEALING WITH SOME SEVERE STORMS...ESPECIALLY
OVER EASTERN AREAS WHERE OPERATIONAL MODELS ARE SURPRISINGLY
AGGRESSIVE IN DEVELOPING THE INSTABILITY. IF ENOUGH SUN CAN BREAK
THROUGH...WINDS ALOFT ARE PRETTY IMPRESSIVE AND STRONG WIND GUSTS
COULD MATERIALIZE.
HIGH TEMPS FOR SUNDAY ARE EXPECTED TO BE IN THE LOWER TO MID 80S
OVERALL BUT THE RAIN-COOLED WILL SEE HIGHS REACHING THE MID TO UPPER
70S. IT SHOULD BE THE LAST WIDESPREAD VERY WARM AND HUMID DAY FOR A
WHILE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
HIGH PROBABILITY FORECASTS FROM ENSEMBLES IMPLIES THE FRONT IS
THROUGH PA IN THE 00 TO 1200 UTC TIME-FRAME MONDAY. BY ABOUT 0600
UTC MONDAY THE PRECIPITABLE WATER (PW) VALUES SHOULD BE AT OR
SLIGHTLY BELOW NORMAL. THIS IMPLIES MOST OF THE RESIDUAL SHOWER
ACTIVITY FROM SUNDAY SHOULD PUSH TO THE EAST A FEW HOURS EITHER
SIDE OF MIDNIGHT.
BY MONDAY EVENING THE PW FALLS TO -1SIGMA BELOW NORMAL IMPLYING
COOL DRY CONDITIONS MONDAY NIGHT AND TUESDAY. PW SHOULD RETURN
TOWARD NORMAL SOMETIME WEDNESDAY IMPLYING A GOOD 2-3 DAYS OF DRY
WEATHER BEHIND THE FRONT. THE COLD AIR AND LOW-LEVEL ANTICYCLONE
LAG THE DRY AIR IMPLYING TUESDAY MORNING COULD BE THE COLDEST
MORNING WHEN 850 HPA TEMPS WILL BE BELOW NORMAL. THE HIGH PRESSURE
BUILDS IN TUES-WED SO SHOULD BE CHILLY OVERNIGHT WEDNESDAY TOO.
AS THE ANTICYCLONE SORT OF HANGS UP TO OUR NORTHEAST WE SHOULD GET
A STABLE SITUATION WITH EASTERLY FLOW...SETTING UP A NICE
BOUNDARY..THEN THE FIRST SURGE OF MOISTURE COMES OVER WESTERN PA
POTENTIALLY OVERNIGHT WEDNESDAY OR THURSDAY IMPLYING INCREASE IN
SHOWERS BY THURSDAY IN THE WEST...STILL LIGHT AND NOT A
SIGNIFICANT THREAT. WITH THE HIGH TO THE EAST COULD BE A CLOUDY
PERIOD OVER WEST/CENTRAL AREAS AS WE HAVE AN IMPLIED BOUNDARY TO
FOCUS CLOUDS AND OVERRUNNING SHOWERS.
BETWEEN THE MOISTURE OVER THE SW ATLANTIC AND THE IMPLIED BOUNDARY
PUSHING INTO PA FROM THE WEST...MOISTURE AND SHOWER POTENTIAL
SHOULD INCREASE THURSDAY INTO FRIDAY. IF THE BOUNDARY CAN PUSH
THROUGH FRIDAY OR EARLY SATURDAY WE HAVE THE POTENTIAL FOR A GOOD
WEEKEND. GEFS/CMCE IMPLY THAT A LOW-LEVEL JET AND MOISTURE PLUME
PUSH THROUGH FRIDAY AHEAD OF THIS FRONTAL BOUNDARY.
SO...DRYING OUT FAST MONDAY AROUND MIDNIGHT...DRY PERIOD MONDAY
THROUGH WED AND TEMPS NEAR OR SLIGHTLY BELOW NORMAL...THEN
INCREASING CHANCE SHOWERS. BEST CHANCE RAIN AT THIS TIME WOULD BE
IN THE LATE THURSDAY EARLY SATURDAY TIME-FRAME. WHICH WILL CHANGE.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
A CORRIDOR OF GREATER MOISTURE AND WINDS ALOFT WILL PUSH INTO NW
PA LATE TONIGHT...RESULTING IN AN INCREASING CHC OF LATE NIGHT
SHRA/TSRA AT BFD. ELSEWHERE...EXPECT GENERALLY GOOD FLYING CONDS
OVERNIGHT WITH WIDESPREAD VFR CONDS AND LGT WINDS. AS HAS OCCURRED
THE LAST COUPLE MORNINGS...A BIT OF FOG IS POSSIBLE ARND DAWN AT
LNS.
THE AFOREMENTIONED CORRIDOR OF MOISTURE AND WINDS ALOFT WILL BRING
SHOWERS AND THE POTENTIAL OF MVFR CIGS TO THE CENTRAL MTNS DURING
THE LATE MORNING HOURS. BY AFTERNOON...DIURNAL HEATING/STEEPENING
LAPSE RTS SHOULD CAUSE ANY CIGS TO RISE ABV 3 KFT. HOWEVER...THE
THREAT TO AVIATION WILL SHIFT TOWARD THE POTENTIAL OF LOCALLY
STRONG THUNDERSTORMS...ESP OVR THE EASTERN HALF OF THE STATE. A
SLOW-MOVING COLD FRONT WILL SAG SE ACROSS THE REGION SUNDAY
EVENING...BRINGING DRIER AIR AND ENDING THE THREAT OF TSRA FROM
NW TO SE.
OUTLOOK...
MON...LOW CIGS/FOG POSS EARLY OVR W MTNS.
TUE-WED...NO SIG WX EXPECTED.
THU...ISOLD PM THUNDERSTORM IMPACTS POSS W MTNS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...GRUMM/RXR
NEAR TERM...DEVOIR/RXR
SHORT TERM...RXR
LONG TERM...GRUMM
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1035 PM EDT SAT JUN 1 2013
.SYNOPSIS...
A STRONG RIDGE AND RELATIVELY WARM MOIST AIR OVER OUR REGION WILL
BE DISPLACED BY A FRONTAL SYSTEM SUNDAY. BEHIND THE FRONT AND OVER
THE COMING WEEK A TROUGH WILL DOMINATE OUR REGION WITH GENERALLY
COOLER AND DRIER AIR PREVAILING. OUR BEST CHANCE OF SHOWERS AND
THUNDERSTORMS WILL BE AHEAD OF THE FRONTAL SYSTEM SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
FOR THE OVERNIGHT...LOOKING UPSTREAM...LAKE BREEZE INTERACTION
WITH GREATER MOISTURE AND INSTABILITY CONTS TO YIELED SCATTERED
STORMS FROM EASTERN OHIO TO THE IMMEDIATE LAKE ERIE AND LAKE
ONTARIO SHORELINES. PREVAILING SOUTHERLY COMPONENT HAS BEEN STRONG
ENOUGH TO PREVENT ANY EASTWARD DRIFT OF THE THE BOUNDARY THUS
FAR...SPARING MY NORTHWEST COUNTIES.
LATEST RAP INDICATES THAT WILL CONTINUE TO BE THE CASE FOR THE
REST OF THE EVENING...WITH POPS RAMPING UP AFTER MIDNIGHT AND
INCREASING FROM WEST TO EAST THEREAFTER. THIS ACTIVITY COMES
ALONG THE LEADING EDGE OF A STRENGTHENING 40-50KT 850 MB JET AND
ANOMALOUS BUT FAIRLY NARROW PLUME OF DEEPER LAYER MOISTURE (~1.65"
PW) TRACKING TO THE ALLEGHENY FRONT BY 12Z SUN. SO... WILL KEEP
POPS UP ALONG MY WESTERN AND NORTHWESTERN BORDERS OVERNIGHT. AS
PREVIOUSLY MENTIONED...POTENTIAL FOR SOME HEAVIER DOWNPOURS AS
PWATS REMAIN ABOVE NORMAL.
TEMPS REMAIN MILD OVERNIGHT IN SW FLOW...WITH HUMID LOWS ONLY
FALLING INTO THE 60S.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
AN APPROACHING COLD FRONT WILL BRING MORE WIDESPREAD SHOWERS AND
THUNDERSTORMS ON SUNDAY...EARLIER IN THE WEST AND FROM MIDDAY ON IN
THE EAST. WE COULD BE DEALING WITH SOME SEVERE STORMS...ESPECIALLY
OVER EASTERN AREAS WHERE OPERATIONAL MODELS ARE SURPRISINGLY
AGGRESSIVE IN DEVELOPING THE INSTABILITY. IF ENOUGH SUN CAN BREAK
THROUGH...WINDS ALOFT ARE PRETTY IMPRESSIVE AND STRONG WIND GUSTS
COULD MATERIALIZE.
HIGH TEMPS FOR SUNDAY ARE EXPECTED TO BE IN THE LOWER TO MID 80S
OVERALL BUT THE RAIN-COOLED WILL SEE HIGHS REACHING THE MID TO UPPER
70S. IT SHOULD BE THE LAST WIDESPREAD VERY WARM AND HUMID DAY FOR A
WHILE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
HIGH PROBABILITY FORECASTS FROM ENSEMBLES IMPLIES THE FRONT IS
THROUGH PA IN THE 00 TO 1200 UTC TIME-FRAME MONDAY. BY ABOUT 0600
UTC MONDAY THE PRECIPITABLE WATER (PW) VALUES SHOULD BE AT OR
SLIGHTLY BELOW NORMAL. THIS IMPLIES MOST OF THE RESIDUAL SHOWER
ACTIVITY FROM SUNDAY SHOULD PUSH TO THE EAST A FEW HOURS EITHER
SIDE OF MIDNIGHT.
BY MONDAY EVENING THE PW FALLS TO -1SIGMA BELOW NORMAL IMPLYING
COOL DRY CONDITIONS MONDAY NIGHT AND TUESDAY. PW SHOULD RETURN
TOWARD NORMAL SOMETIME WEDNESDAY IMPLYING A GOOD 2-3 DAYS OF DRY
WEATHER BEHIND THE FRONT. THE COLD AIR AND LOW-LEVEL ANTICYCLONE
LAG THE DRY AIR IMPLYING TUESDAY MORNING COULD BE THE COLDEST
MORNING WHEN 850 HPA TEMPS WILL BE BELOW NORMAL. THE HIGH PRESSURE
BUILDS IN TUES-WED SO SHOULD BE CHILLY OVERNIGHT WEDNESDAY TOO.
AS THE ANTICYCLONE SORT OF HANGS UP TO OUR NORTHEAST WE SHOULD GET
A STABLE SITUATION WITH EASTERLY FLOW...SETTING UP A NICE
BOUNDARY..THEN THE FIRST SURGE OF MOISTURE COMES OVER WESTERN PA
POTENTIALLY OVERNIGHT WEDNESDAY OR THURSDAY IMPLYING INCREASE IN
SHOWERS BY THURSDAY IN THE WEST...STILL LIGHT AND NOT A
SIGNIFICANT THREAT. WITH THE HIGH TO THE EAST COULD BE A CLOUDY
PERIOD OVER WEST/CENTRAL AREAS AS WE HAVE AN IMPLIED BOUNDARY TO
FOCUS CLOUDS AND OVERRUNNING SHOWERS.
BETWEEN THE MOISTURE OVER THE SW ATLANTIC AND THE IMPLIED BOUNDARY
PUSHING INTO PA FROM THE WEST...MOISTURE AND SHOWER POTENTIAL
SHOULD INCREASE THURSDAY INTO FRIDAY. IF THE BOUNDARY CAN PUSH
THROUGH FRIDAY OR EARLY SATURDAY WE HAVE THE POTENTIAL FOR A GOOD
WEEKEND. GEFS/CMCE IMPLY THAT A LOW-LEVEL JET AND MOISTURE PLUME
PUSH THROUGH FRIDAY AHEAD OF THIS FRONTAL BOUNDARY.
SO...DRYING OUT FAST MONDAY AROUND MIDNIGHT...DRY PERIOD MONDAY
THROUGH WED AND TEMPS NEAR OR SLIGHTLY BELOW NORMAL...THEN
INCREASING CHANCE SHOWERS. BEST CHANCE RAIN AT THIS TIME WOULD BE
IN THE LATE THURSDAY EARLY SATURDAY TIME-FRAME. WHICH WILL CHANGE.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
EARLY EVENING VISIBLE SATL IMAGERY SHOWING SOME VERTICAL
DEVELOPMENT TO LINE OF CU ALONG THE SPINE OF THE APPALACHIANS FROM
AOO TO UNV AND IPT. CAN/T RULE OUT AN ISOLD SHRA/TSRA AT THESE
AIRFIELDS EARLY THIS EVENING. HOWEVER...CHANCE TOO SMALL TO
WARRANT MENTION IN TAFS ATTM.
A CORRIDOR OF GREATER MOISTURE AND WINDS ALOFT WILL PUSH INTO NW
PA LATE TONIGHT...RESULTING IN A GREATER CHC OF LATE NIGHT
SHRA/TSRA AT BFD. ELSEWHERE...EXPECT GENERALLY GOOD FLYING CONDS
OVERNIGHT WITH WIDESPREAD VFR CONDS AND LGT WINDS. AS HAS
OCCURRED THE LAST COUPLE MORNINGS...A BIT OF FOG IS POSSIBLE ARND
DAWN AT LNS.
THE AFOREMENTIONED CORRIDOR OF MOISTURE AND WINDS ALOFT WILL BRING
SHOWERS AND THE POTENTIAL OF MVFR CIGS TO THE CENTRAL MTNS DURING
THE LATE MORNING HOURS. BY AFTERNOON...DIURNAL HEATING/STEEPENING
LAPSE RTS SHOULD CAUSE ANY CIGS TO RISE ABV 3 KFT. HOWEVER...THE
THREAT TO AVIATION WILL SHIFT TOWARD THE POTENTIAL OF LOCALLY
STRONG THUNDERSTORMS...ESP OVR THE EASTERN HALF OF THE STATE. A
SLOW-MOVING COLD FRONT WILL SAG SE ACROSS THE REGION SUNDAY
EVENING...BRINGING DRIER AIR AND ENDING THE THREAT OF TSRA FROM
NW TO SE.
OUTLOOK...
MON...LOW CIGS/FOG POSS EARLY OVR W MTNS.
TUE-WED...NO SIG WX EXPECTED.
THU...ISOLD PM THUNDERSTORM IMPACTS POSS W MTNS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...GRUMM/RXR
NEAR TERM...DEVOIR/RXR
SHORT TERM...RXR
LONG TERM...GRUMM
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
906 PM EDT SAT JUN 1 2013
.SYNOPSIS...
A STRONG RIDGE AND RELATIVELY WARM MOIST AIR OVER OUR REGION WILL
BE DISPLACED BY A FRONTAL SYSTEM SUNDAY. BEHIND THE FRONT AND OVER
THE COMING WEEK A TROUGH WILL DOMINATE OUR REGION WITH GENERALLY
COOLER AND DRIER AIR PREVAILING. OUR BEST CHANCE OF SHOWERS AND
THUNDERSTORMS WILL BE AHEAD OF THE FRONTAL SYSTEM SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
600 MB WARM CAP AND DRY AIR ENTRAINMENT ALOFT HELPED TO DISSIPATE
DIURNALLY DRIVEN ISOLATED SHOWERS.
FOR THE OVERNIGHT...LOOKING UPSTREAM...LAKE BREEZE INTERACTION WITH
GREATER MOISTURE AND INSTABILITY CONTS TO YIELED SCATTERED STORMS
FROM EASTERN OHIO TO THE IMMEDIATE LAKE ERIE AND LAKE ONTARIO
SHORELINES. PREVAILING SOUTHERLY COMPONENT HAS BEEN STRONG ENOUGH
TO PREVENT ANY EASTWARD DRIFT OF THE THE BOUNDARY THUS
FAR...SPARING MY NORTHWEST COUNTIES.
LATEST RAP INDICATES THAT WILL CONTINUE TO BE THE CASE FOR THE
REST OF THE EVENING...WITH POPS RAMPING UP AFTER MIDNIGHT AND
INCREASING FROM WEST TO EAST THEREAFTER. THIS ACTIVITY COMES
ALONG THE LEADING EDGE OF A STRENGTHENING 40-50KT 850 MB JET AND
ANOMALOUS BUT FAIRLY NARROW PLUME OF DEEPER LAYER MOISTURE (~1.65"
PW) TRACKING TO THE ALLEGHENY FRONT BY 12Z SUN. SO... WILL KEEP
POPS UP ALONG MY WESTERN AND NORTHWESTERN BORDERS OVERNIGHT. AS
PREVIOUSLY MENTIONED...POTENTIAL FOR SOME HEAVIER DOWNPOURS AS
PWATS REMAIN ABOVE NORMAL.
TEMPS REMAIN MILD OVERNIGHT IN SW FLOW...WITH HUMID LOWS ONLY
FALLING INTO THE 60S.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
AN APPROACHING COLD FRONT WILL BRING MORE WIDESPREAD SHOWERS AND
THUNDERSTORMS ON SUNDAY...EARLIER IN THE WEST AND FROM MIDDAY ON IN
THE EAST. WE COULD BE DEALING WITH SOME SEVERE STORMS...ESPECIALLY
OVER EASTERN AREAS WHERE OPERATIONAL MODELS ARE SURPRISINGLY
AGGRESSIVE IN DEVELOPING THE INSTABILITY. IF ENOUGH SUN CAN BREAK
THROUGH...WINDS ALOFT ARE PRETTY IMPRESSIVE AND STRONG WIND GUSTS
COULD MATERIALIZE.
HIGH TEMPS FOR SUNDAY ARE EXPECTED TO BE IN THE LOWER TO MID 80S
OVERALL BUT THE RAIN-COOLED WILL SEE HIGHS REACHING THE MID TO UPPER
70S. IT SHOULD BE THE LAST WIDESPREAD VERY WARM AND HUMID DAY FOR A
WHILE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
HIGH PROBABILITY FORECASTS FROM ENSEMBLES IMPLIES THE FRONT IS
THROUGH PA IN THE 00 TO 1200 UTC TIME-FRAME MONDAY. BY ABOUT 0600
UTC MONDAY THE PRECIPITABLE WATER (PW) VALUES SHOULD BE AT OR
SLIGHTLY BELOW NORMAL. THIS IMPLIES MOST OF THE RESIDUAL SHOWER
ACTIVITY FROM SUNDAY SHOULD PUSH TO THE EAST A FEW HOURS EITHER
SIDE OF MIDNIGHT.
BY MONDAY EVENING THE PW FALLS TO -1SIGMA BELOW NORMAL IMPLYING
COOL DRY CONDITIONS MONDAY NIGHT AND TUESDAY. PW SHOULD RETURN
TOWARD NORMAL SOMETIME WEDNESDAY IMPLYING A GOOD 2-3 DAYS OF DRY
WEATHER BEHIND THE FRONT. THE COLD AIR AND LOW-LEVEL ANTICYCLONE
LAG THE DRY AIR IMPLYING TUESDAY MORNING COULD BE THE COLDEST
MORNING WHEN 850 HPA TEMPS WILL BE BELOW NORMAL. THE HIGH PRESSURE
BUILDS IN TUES-WED SO SHOULD BE CHILLY OVERNIGHT WEDNESDAY TOO.
AS THE ANTICYCLONE SORT OF HANGS UP TO OUR NORTHEAST WE SHOULD GET
A STABLE SITUATION WITH EASTERLY FLOW...SETTING UP A NICE
BOUNDARY..THEN THE FIRST SURGE OF MOISTURE COMES OVER WESTERN PA
POTENTIALLY OVERNIGHT WEDNESDAY OR THURSDAY IMPLYING INCREASE IN
SHOWERS BY THURSDAY IN THE WEST...STILL LIGHT AND NOT A
SIGNIFICANT THREAT. WITH THE HIGH TO THE EAST COULD BE A CLOUDY
PERIOD OVER WEST/CENTRAL AREAS AS WE HAVE AN IMPLIED BOUNDARY TO
FOCUS CLOUDS AND OVERRUNNING SHOWERS.
BETWEEN THE MOISTURE OVER THE SW ATLANTIC AND THE IMPLIED BOUNDARY
PUSHING INTO PA FROM THE WEST...MOISTURE AND SHOWER POTENTIAL
SHOULD INCREASE THURSDAY INTO FRIDAY. IF THE BOUNDARY CAN PUSH
THROUGH FRIDAY OR EARLY SATURDAY WE HAVE THE POTENTIAL FOR A GOOD
WEEKEND. GEFS/CMCE IMPLY THAT A LOW-LEVEL JET AND MOISTURE PLUME
PUSH THROUGH FRIDAY AHEAD OF THIS FRONTAL BOUNDARY.
SO...DRYING OUT FAST MONDAY AROUND MIDNIGHT...DRY PERIOD MONDAY
THROUGH WED AND TEMPS NEAR OR SLIGHTLY BELOW NORMAL...THEN
INCREASING CHANCE SHOWERS. BEST CHANCE RAIN AT THIS TIME WOULD BE
IN THE LATE THURSDAY EARLY SATURDAY TIME-FRAME. WHICH WILL CHANGE.
&&
.AVIATION /01Z SUNDAY THROUGH THURSDAY/...
EARLY EVENING VISIBLE SATL IMAGERY SHOWING SOME VERTICAL
DEVELOPMENT TO LINE OF CU ALONG THE SPINE OF THE APPALACHIANS FROM
AOO TO UNV AND IPT. CAN/T RULE OUT AN ISOLD SHRA/TSRA AT THESE
AIRFIELDS EARLY THIS EVENING. HOWEVER...CHANCE TOO SMALL TO
WARRANT MENTION IN TAFS ATTM.
A CORRIDOR OF GREATER MOISTURE AND WINDS ALOFT WILL PUSH INTO NW
PA LATE TONIGHT...RESULTING IN A GREATER CHC OF LATE NIGHT
SHRA/TSRA AT BFD. ELSEWHERE...EXPECT GENERALLY GOOD FLYING CONDS
OVERNIGHT WITH WIDESPREAD VFR CONDS AND LGT WINDS. AS HAS
OCCURRED THE LAST COUPLE MORNINGS...A BIT OF FOG IS POSSIBLE ARND
DAWN AT LNS.
THE AFOREMENTIONED CORRIDOR OF MOISTURE AND WINDS ALOFT WILL BRING
SHOWERS AND THE POTENTIAL OF MVFR CIGS TO THE CENTRAL MTNS DURING
THE LATE MORNING HOURS. BY AFTERNOON...DIURNAL HEATING/STEEPENING
LAPSE RTS SHOULD CAUSE ANY CIGS TO RISE ABV 3 KFT. HOWEVER...THE
THREAT TO AVIATION WILL SHIFT TOWARD THE POTENTIAL OF LOCALLY
STRONG THUNDERSTORMS...ESP OVR THE EASTERN HALF OF THE STATE. A
SLOW-MOVING COLD FRONT WILL SAG SE ACROSS THE REGION SUNDAY
EVENING...BRINGING DRIER AIR AND ENDING THE THREAT OF TSRA FROM
NW TO SE.
OUTLOOK...
MON...LOW CIGS/FOG POSS EARLY OVR W MTNS.
TUE-WED...NO SIG WX EXPECTED.
THU...ISOLD PM THUNDERSTORM IMPACTS POSS W MTNS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...GRUMM/RXR
NEAR TERM...DEVOIR/RXR
SHORT TERM...RXR
LONG TERM...GRUMM
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
806 PM EDT SAT JUN 1 2013
.SYNOPSIS...
A STRONG RIDGE AND RELATIVELY WARM MOIST AIR OVER OUR REGION WILL
BE DISPLACED BY A FRONTAL SYSTEM SUNDAY. BEHIND THE FRONT AND OVER
THE COMING WEEK A TROUGH WILL DOMINATE OUR REGION WITH GENERALLY
COOLER AND DRIER AIR PREVAILING. OUR BEST CHANCE OF SHOWERS AND
THUNDERSTORMS WILL BE AHEAD OF THE FRONTAL SYSTEM SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
600 MB WARM CAP AND DRY AIR ENTRAINMENT ALOFT HAVE PRETTY MUCH
TAKEN CARE OF THE ISOLATED SHOWERS WHICH POPPED UP LATE THIS AFTERNOON.
LOOKING UPSTREAM...LAKE BREEZE INTERACTION WITH GREATER MOISTURE
AND INSTABILITY HAS YIELED SCATTERED STORMS FROM EASTERN OHIO TO
THE IMMEDIATE LAKE ERIE AND LAKE ONTARIO SHORELINES. PREVAILING
SOUTHERLY COMPONENT HAS BEEN STRONG ENOUGH TO PREVENT ANY EASTWARD
DRIFT OF THE THE BOUNDARY...AND SO FAR THE NORTHWEST HAS BEEN
SPARED THIS EVENING. LATEST RAP INDICATES THAT WILL CONTINUE TO BE
THE CASE FOR THE REST OF THIS EVENING...FOLLOWED BY SOME SCATTERED
COVERAGE OF SHOWERS AND ISOLATED THUNDER AFTER MIDNIGHT FROM THE
WEST CENTRAL MOUNTAINS TO THE NORTHWEST MOUNTAINS. THIS ACTIVITY
COMES ALONG THE LEADING EDGE OF A STRENGTHENING 40-50KT 850 MB
JET AND ANOMALOUS BUT FAIRLY NARROW PLUME OF DEEPER LAYER MOISTURE
(~1.65" PW) TRACKING TO THE ALLEGHENY FRONT BY 12Z SUN. SO...
WILL KEEP POPS UP ALONG MY WESTERN AND NORTHWESTERN BORDERS
OVERNIGHT. AS PREVIOUSLY MENTIONED...POTENTIAL FOR SOME HEAVIER
DOWNPOURS AS PWATS REMAIN ABOVE NORMAL.
TEMPS REMAIN MILD OVERNIGHT IN SW FLOW...WITH HUMID LOWS ONLY
FALLING INTO THE 60S.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
AN APPROACHING COLD FRONT WILL BRING MORE WIDESPREAD SHOWERS AND
THUNDERSTORMS ON SUNDAY...EARLIER IN THE WEST AND FROM MIDDAY ON IN
THE EAST. WE COULD BE DEALING WITH SOME SEVERE STORMS...ESPECIALLY
OVER EASTERN AREAS WHERE OPERATIONAL MODELS ARE SURPRISINGLY
AGGRESSIVE IN DEVELOPING THE INSTABILITY. IF ENOUGH SUN CAN BREAK
THROUGH...WINDS ALOFT ARE PRETTY IMPRESSIVE AND STRONG WIND GUSTS
COULD MATERIALIZE.
HIGH TEMPS FOR SUNDAY ARE EXPECTED TO BE IN THE LOWER TO MID 80S
OVERALL BUT THE RAIN-COOLED WILL SEE HIGHS REACHING THE MID TO UPPER
70S. IT SHOULD BE THE LAST WIDESPREAD VERY WARM AND HUMID DAY FOR A
WHILE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
HIGH PROBABILITY FORECASTS FROM ENSEMBLES IMPLIES THE FRONT IS
THROUGH PA IN THE 00 TO 1200 UTC TIME-FRAME MONDAY. BY ABOUT 0600
UTC MONDAY THE PRECIPITABLE WATER (PW) VALUES SHOULD BE AT OR
SLIGHTLY BELOW NORMAL. THIS IMPLIES MOST OF THE RESIDUAL SHOWER
ACTIVITY FROM SUNDAY SHOULD PUSH TO THE EAST A FEW HOURS EITHER
SIDE OF MIDNIGHT.
BY MONDAY EVENING THE PW FALLS TO -1SIGMA BELOW NORMAL IMPLYING
COOL DRY CONDITIONS MONDAY NIGHT AND TUESDAY. PW SHOULD RETURN
TOWARD NORMAL SOMETIME WEDNESDAY IMPLYING A GOOD 2-3 DAYS OF DRY
WEATHER BEHIND THE FRONT. THE COLD AIR AND LOW-LEVEL ANTICYCLONE
LAG THE DRY AIR IMPLYING TUESDAY MORNING COULD BE THE COLDEST
MORNING WHEN 850 HPA TEMPS WILL BE BELOW NORMAL. THE HIGH PRESSURE
BUILDS IN TUES-WED SO SHOULD BE CHILLY OVERNIGHT WEDNESDAY TOO.
AS THE ANTICYCLONE SORT OF HANGS UP TO OUR NORTHEAST WE SHOULD GET
A STABLE SITUATION WITH EASTERLY FLOW...SETTING UP A NICE
BOUNDARY..THEN THE FIRST SURGE OF MOISTURE COMES OVER WESTERN PA
POTENTIALLY OVERNIGHT WEDNESDAY OR THURSDAY IMPLYING INCREASE IN
SHOWERS BY THURSDAY IN THE WEST...STILL LIGHT AND NOT A
SIGNIFICANT THREAT. WITH THE HIGH TO THE EAST COULD BE A CLOUDY
PERIOD OVER WEST/CENTRAL AREAS AS WE HAVE AN IMPLIED BOUNDARY TO
FOCUS CLOUDS AND OVERRUNNING SHOWERS.
BETWEEN THE MOISTURE OVER THE SW ATLANTIC AND THE IMPLIED BOUNDARY
PUSHING INTO PA FROM THE WEST...MOISTURE AND SHOWER POTENTIAL
SHOULD INCREASE THURSDAY INTO FRIDAY. IF THE BOUNDARY CAN PUSH
THROUGH FRIDAY OR EARLY SATURDAY WE HAVE THE POTENTIAL FOR A GOOD
WEEKEND. GEFS/CMCE IMPLY THAT A LOW-LEVEL JET AND MOISTURE PLUME
PUSH THROUGH FRIDAY AHEAD OF THIS FRONTAL BOUNDARY.
SO...DRYING OUT FAST MONDAY AROUND MIDNIGHT...DRY PERIOD MONDAY
THROUGH WED AND TEMPS NEAR OR SLIGHTLY BELOW NORMAL...THEN
INCREASING CHANCE SHOWERS. BEST CHANCE RAIN AT THIS TIME WOULD BE
IN THE LATE THURSDAY EARLY SATURDAY TIME-FRAME. WHICH WILL CHANGE.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
EARLY EVENING VISIBLE SATL IMAGERY SHOWING SOME VERTICAL
DEVELOPMENT TO LINE OF CU ALONG THE SPINE OF THE APPALACHIANS FROM
AOO TO UNV AND IPT. CAN/T RULE OUT AN ISOLD SHRA/TSRA AT THESE
AIRFIELDS EARLY THIS EVENING. HOWEVER...CHANCE TOO SMALL TO
WARRANT MENTION IN TAFS ATTM.
A CORRIDOR OF GREATER MOISTURE AND WINDS ALOFT WILL PUSH INTO NW
PA LATE TONIGHT...RESULTING IN A GREATER CHC OF LATE NIGHT
SHRA/TSRA AT BFD. ELSEWHERE...EXPECT GENERALLY GOOD FLYING CONDS
OVERNIGHT WITH WIDESPREAD VFR CONDS AND LGT WINDS. AS HAS
OCCURRED THE LAST COUPLE MORNINGS...A BIT OF FOG IS POSSIBLE ARND
DAWN AT LNS.
THE AFOREMENTIONED CORRIDOR OF MOISTURE AND WINDS ALOFT WILL BRING
SHOWERS AND THE POTENTIAL OF MVFR CIGS TO THE CENTRAL MTNS DURING
THE LATE MORNING HOURS. BY AFTERNOON...DIURNAL HEATING/STEEPENING
LAPSE RTS SHOULD CAUSE ANY CIGS TO RISE ABV 3 KFT. HOWEVER...THE
THREAT TO AVIATION WILL SHIFT TOWARD THE POTENTIAL OF LOCALLY
STRONG THUNDERSTORMS...ESP OVR THE EASTERN HALF OF THE STATE. A
SLOW-MOVING COLD FRONT WILL SAG SE ACROSS THE REGION SUNDAY
EVENING...BRINGING DRIER AIR AND ENDING THE THREAT OF TSRA FROM
NW TO SE.
OUTLOOK...
MON...LOW CIGS/FOG POSS EARLY OVR W MTNS.
TUE-WED...NO SIG WX EXPECTED.
THU...ISOLD PM THUNDERSTORM IMPACTS POSS W MTNS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...GRUMM/RXR
NEAR TERM...DEVOIR/RXR
SHORT TERM...RXR
LONG TERM...GRUMM
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
736 PM EDT SAT JUN 1 2013
.SYNOPSIS...
A STRONG RIDGE AND RELATIVELY WARM MOIST AIR OVER OUR REGION WILL
BE DISPLACED BY A FRONTAL SYSTEM SUNDAY. BEHIND THE FRONT AND OVER
THE COMING WEEK A TROUGH WILL DOMINATE OUR REGION WITH GENERALLY
COOLER AND DRIER AIR PREVAILING. OUR BEST CHANCE OF SHOWERS AND
THUNDERSTORMS WILL BE AHEAD OF THE FRONTAL SYSTEM SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
600 MB WARM CAP AND DRY AIR ENTRAINMENT ALOFT HAVE PRETTY MUCH
TAKEN CARE OF THE ISOLATED SHOWERS WHICH POPPED UP LATE THIS AFTERNOON.
LOOKING UPSTREAM...LAKE BREEZE INTERACTION WITH GREATER MOISTURE
AND INSTABILITY HAS YIELED SCATTERED STORMS FROM EASTERN OHIO TO
THE IMMEDIATE LAKE ERIE AND LAKE ONTARIO SHORELINES. PREVAILING
SOUTHERLY COMPONENT HAS BEEN STRONG ENOUGH TO PREVENT ANY EASTWARD
DRIFT OF THE THE BOUNDARY...AND SO FAR THE NORTHWEST HAS BEEN
SPARED THIS EVENING. LATEST RAP INDICATES THAT WILL CONTINUE TO BE
THE CASE FOR THE REST OF THIS EVENING...FOLLOWED BY SOME SCATTERED
COVERAGE OF SHOWERS AND ISOLATED THUNDER AFTER MIDNIGHT FROM THE
WEST CENTRAL MOUNTAINS TO THE NORTHWEST MOUNTAINS. THIS ACTIVITY
COMES ALONG THE LEADING EDGE OF A STRENGTHENING 40-50KT 850 MB
JET AND ANOMALOUS BUT FAIRLY NARROW PLUME OF DEEPER LAYER MOISTURE
(~1.65" PW) TRACKING TO THE ALLEGHENY FRONT BY 12Z SUN. SO...
WILL KEEP POPS UP ALONG MY WESTERN AND NORTHWESTERN BORDERS
OVERNIGHT. AS PREVIOUSLY MENTIONED...POTENTIAL FOR SOME HEAVIER
DOWNPOURS AS PWATS REMAIN ABOVE NORMAL.
TEMPS REMAIN MILD OVERNIGHT IN SW FLOW...WITH HUMID LOWS ONLY
FALLING INTO THE 60S.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
AN APPROACHING COLD FRONT WILL BRING MORE WIDESPREAD SHOWERS AND
THUNDERSTORMS ON SUNDAY...EARLIER IN THE WEST AND FROM MIDDAY ON IN
THE EAST. WE COULD BE DEALING WITH SOME SEVERE STORMS...ESPECIALLY
OVER EASTERN AREAS WHERE OPERATIONAL MODELS ARE SURPRISINGLY
AGGRESSIVE IN DEVELOPING THE INSTABILITY. IF ENOUGH SUN CAN BREAK
THROUGH...WINDS ALOFT ARE PRETTY IMPRESSIVE AND STRONG WIND GUSTS
COULD MATERIALIZE.
HIGH TEMPS FOR SUNDAY ARE EXPECTED TO BE IN THE LOWER TO MID 80S
OVERALL BUT THE RAIN-COOLED WILL SEE HIGHS REACHING THE MID TO UPPER
70S. IT SHOULD BE THE LAST WIDESPREAD VERY WARM AND HUMID DAY FOR A
WHILE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
HIGH PROBABILITY FORECASTS FROM ENSEMBLES IMPLIES THE FRONT IS
THROUGH PA IN THE 00 TO 1200 UTC TIME-FRAME MONDAY. BY ABOUT 0600
UTC MONDAY THE PRECIPITABLE WATER (PW) VALUES SHOULD BE AT OR
SLIGHTLY BELOW NORMAL. THIS IMPLIES MOST OF THE RESIDUAL SHOWER
ACTIVITY FROM SUNDAY SHOULD PUSH TO THE EAST A FEW HOURS EITHER
SIDE OF MIDNIGHT.
BY MONDAY EVENING THE PW FALLS TO -1SIGMA BELOW NORMAL IMPLYING
COOL DRY CONDITIONS MONDAY NIGHT AND TUESDAY. PW SHOULD RETURN
TOWARD NORMAL SOMETIME WEDNESDAY IMPLYING A GOOD 2-3 DAYS OF DRY
WEATHER BEHIND THE FRONT. THE COLD AIR AND LOW-LEVEL ANTICYCLONE
LAG THE DRY AIR IMPLYING TUESDAY MORNING COULD BE THE COLDEST
MORNING WHEN 850 HPA TEMPS WILL BE BELOW NORMAL. THE HIGH PRESSURE
BUILDS IN TUES-WED SO SHOULD BE CHILLY OVERNIGHT WEDNESDAY TOO.
AS THE ANTICYCLONE SORT OF HANGS UP TO OUR NORTHEAST WE SHOULD GET
A STABLE SITUATION WITH EASTERLY FLOW...SETTING UP A NICE
BOUNDARY..THEN THE FIRST SURGE OF MOISTURE COMES OVER WESTERN PA
POTENTIALLY OVERNIGHT WEDNESDAY OR THURSDAY IMPLYING INCREASE IN
SHOWERS BY THURSDAY IN THE WEST...STILL LIGHT AND NOT A
SIGNIFICANT THREAT. WITH THE HIGH TO THE EAST COULD BE A CLOUDY
PERIOD OVER WEST/CENTRAL AREAS AS WE HAVE AN IMPLIED BOUNDARY TO
FOCUS CLOUDS AND OVERRUNNING SHOWERS.
BETWEEN THE MOISTURE OVER THE SW ATLANTIC AND THE IMPLIED BOUNDARY
PUSHING INTO PA FROM THE WEST...MOISTURE AND SHOWER POTENTIAL
SHOULD INCREASE THURSDAY INTO FRIDAY. IF THE BOUNDARY CAN PUSH
THROUGH FRIDAY OR EARLY SATURDAY WE HAVE THE POTENTIAL FOR A GOOD
WEEKEND. GEFS/CMCE IMPLY THAT A LOW-LEVEL JET AND MOISTURE PLUME
PUSH THROUGH FRIDAY AHEAD OF THIS FRONTAL BOUNDARY.
SO...DRYING OUT FAST MONDAY AROUND MIDNIGHT...DRY PERIOD MONDAY
THROUGH WED AND TEMPS NEAR OR SLIGHTLY BELOW NORMAL...THEN
INCREASING CHANCE SHOWERS. BEST CHANCE RAIN AT THIS TIME WOULD BE
IN THE LATE THURSDAY EARLY SATURDAY TIME-FRAME. WHICH WILL CHANGE.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
HEATING OF THE DAY WILL PRODUCE ISOLATED SHRA/TSRA ACROSS CENTRAL
PA THIS EVENING. AREAL COVERAGE TOO SMALL TO WARRANT MENTION IN
TAFS AT MOST AIRFIELDS. HOWEVER...A CORRIDOR OF GREATER
INSTABILITY AND WINDS ALOFT ACROSS NW PA WILL RESULT IN A GREATER
CHC OF AN EVENING TSRA/SHRA AT BFD. FOR THE REST OF TONIGHT...EXPECT
GENERALLY GOOD FLYING CONDS WITH WIDESPREAD VFR CONDS AND LGT
WINDS. AS HAS OCCURRED THE LAST COUPLE MORNINGS...A BIT OF FOG IS
POSSIBLE ARND DAWN AT LNS.
AN APPROACHING COLD FRONT WILL BRING MORE WIDESPREAD SHOWERS AND
THUNDERSTORMS ON SUNDAY...EARLIER IN THE WEST AND FROM MIDDAY ON
IN THE EAST. WE COULD BE DEALING WITH SOME SEVERE STORMS...ESPECIALLY
OVER EASTERN AREAS. IF ENOUGH SUN CAN BREAK THROUGH...WINDS ALOFT
ARE PRETTY IMPRESSIVE AND STRONG WIND GUSTS COULD MATERIALIZE.
OUTLOOK...
SUN...COLD FRONTAL PASSAGE. THUNDERSTORM IMPACTS LIKELY. SOME TSTMS
MAY BE STRONG...ESP EAST.
MON...LOW CIGS/FOG POSS EARLY OVR W MTNS. OTHERWISE VFR.
TUE-THU...NO SIG WX EXPECTED.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...GRUMM/RXR
NEAR TERM...DEVOIR/RXR
SHORT TERM...RXR
LONG TERM...GRUMM
AVIATION...FITZGERALD/RXR
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
934 PM EDT SAT JUN 1 2013
.DISCUSSION...LINE OF THUNDERSTORMS AHEAD OF COLD FRONT MOVING INTO
LOWER MS VALLEY WAS ACROSS MIDDLE TN LATE THIS AFTERNOON AND HAS
NOW WEAKENED AS IT MOVES ACROSS THE PLATEAU. SCATTERED SHOWERS AND
THUNDERSTORMS DEVELOPED AHEAD OF THE LINE AND HAVE MOVED ACROSS THE
SOUTHWEST HALF OF THE AREA. CURRENT FORECAST LOOKS ABOUT RIGHT.
INCREASED POPS SLIGHTLY WEST AND ADJUSTED TEMPERATURES AND DEW
POINTS DOWN WHERE RAIN HAS OCCURRED. LATEST RUC AND NAM20 GUIDANCE
HAS CONVECTION DYING DOWN NEXT COUPLE HOURS AND THEN REFIRING
AROUND 9Z AS MAIN SHORT WAVE IMPULSE AHEAD OF COLD FRONT MOVES INTO
EAST TN. UPDATED FORECAST ALREADY SENT.
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
TD
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1234 PM CDT FRI MAY 31 2013
.UPDATE...FOR 18Z AVIATION FORECAST
&&
.AVIATION...
MESO CONVECTIVE VORTICITY CENTER ROTATING OVER WEST CENTRAL
KENTUCKY AT 17Z WILL CONTINUE TO LIFT NORTHEAST. BULK OF SHOWERS
AND ISOLATED STORMS ARE PULLING AWAY FROM MIDDLE TENNESSEE AS MCV
LIFTS NORTHEASTWARD LEAVING SUBSIDENCE BEHIND IT. AM SEEING
SCATTERED CONVECTION FIRING EAST OF INTERSTATE 65 BUT NOT
EXPECTING THIS TO AMOUNT TO MUCH. BASICALLY EXPECT AIR MASS ACROSS
MIDDLE TENNESSEE TO BEGIN DRYING OUT DURING THE AFTERNOON AND
CONTINUE THROUGH THE OVERNIGHT IN THE WAKE OF MCV.
BOYD
&&
.PREV DISCUSSION... /ISSUED 948 AM CDT FRI MAY 31 2013/
UPDATE...
LATEST RADAR AND IR SATELLITE IMAGERY DEPICTS A WEAKENING MCS
OVER WESTERN ZONES WITH SHOWERS AND STORMS DIMINISHING IN
COVERAGE AND CLOUD TOPS WARMING SIGNIFICANTLY. ALTHOUGH HRRR
INDICATES ACTIVITY WILL CONTINUE MARCHING EASTWARD THROUGH THE
CWA...APPEARS MUCH OF THE CURRENT PRECIP WILL DISSIPATE PRIOR TO
REACHING THE I-65 CORRIDOR. NEVERTHELESS...VERY MOIST AIRMASS IN
PLACE SHOWN BY THE PWAT OF 1.67 INCHES ON THE 12Z OHX SOUNDING
ALONG WITH CONTINUED DAYTIME HEATING SHOULD SPAWN ADDITIONAL
SCATTERED SHOWERS AND STORMS AHEAD OF DYING MCS LATER TODAY. HAVE
RAISED POPS ACROSS CENTRAL AND WESTERN ZONES FOR THE MORNING HOURS
BASED ON CURRENT TRENDS...AND BUMPED UP CLOUD COVER AND LOWERED
HIGH TEMPS IN THE NORTHWEST. REST OF FORECAST REMAINS UNCHANGED.
SHAMBURGER
PREV DISCUSSION... /ISSUED 831 AM CDT FRI MAY 31 2013/
AVIATION UPDATE...
GOOD ROUND OF SHOWERS AND STORMS OVER WESTERN TENNESSEE HAVE
MOVED INTO NORTHWEST TENNESSEE WITH ISOLATED RENEGADE SHOWERS
FIXING TO MOVE INTO DAVIDSON COUNTY. H-TRIPLE-R DRIVE SHOWERS AND
STORMS CURRENTLY IN WEST TENNESSEE EASTWARD AS WE GO THROUGH THE
MORNING HOURS.
INFRARED SATELLITE LOOP SHOW TOPS WARMING ACROSS WESTERN TENNESSEE
WITH LIGHTNING STRIKES DECREASING.
BOYD
PREV DISCUSSION... /ISSUED 622 AM CDT FRI MAY 31 2013/
UPDATE...FOR 12Z AVIATION DISCUSSION.
AVIATION...12Z AVIATION DISCUSSION.
UNCERTAINTIES...HOW FAR WILL MOISTURE ASSOCIATED WITH DYING MCS MAKE IT INTO
MID STATE AND ASSOCIATED SHWR/TSTMS CHANCES. WILL GO WITH VFR CEILINGS THRU
01/12Z...WITH MAIN IMPACT OF SHWRS/TSTMS ACROSS CKV FROM 31/13Z-31/18Z. QUESTION
HOW FAR EWD MCS INFLUENCES WILL EXTEND...AND THUS WILL CONTINUE WITH ONLY
VCTS REMARKS AT BOTH BNA/CSV. EXPECT SOME ERROSION OF VFR CU CEILINGS AFTER
31/18Z W TO 31/22Z E...WITH AN INCREASE IN MOISTURE AHEAD OF UPPER LEVEL
DISTURBANCE ALLOWING FOR SCT/BKN STCU/AC/CI FROM 01/07Z W TO 01/12Z E. PER SFC
PRESSURE GRADIENT...EXPECT GUST TO 20KTS POSSIBLE 31/13Z W TO 01/03Z E.
PREV DISCUSSION.../ISSUED 554 AM CDT FRI MAY 31 2013/
UPDATE...
LATEST MODELS INDICATING THAT THE DEEPER MOISTURE WILL INDEED
TRANSITION NORTHEASTWARD ACROSS OUR NORTHWESTERN COUNTIES LATER
THIS MORNING. THIS IS FURTHER CONFIRMED BY RECENT RADAR TRENDS AND
TODAY`S HRRR DATA. WILL GO AHEAD AND INCREASE POPS...PRIMARILY
ACROSS WESTERN AND NORTH CENTRAL ZONES.
PREV DISCUSSION... /ISSUED 333 AM CDT FRI MAY 31 2013/
MAIN COLD FRONTAL BOUNDARY IS STILL LOCATED WELL WEST OF TN AND
RESIDES ALONG THE CENTRAL PLAINS. MAIN FOCUS OF CONVECTION THIS
MORNING IS IN ASSOCIATION WITH A SERIES OF MCS`S FROM AR NE THROUGH
NRN IN. 850MB JET IS COMBINING WITH STRONG IMPULSES WITHIN THE SWLY
FLOW ALOFT TO KEEP THIS CONVECTION GOING OVERNIGHT. MODELS DO SHOW
AN EASTWARD MIGRATION OF THESE DYNAMICS FOR TODAY. ALTHOUGH THE
DYNAMICS WILL WEAKEN...HRRR DOES SUPPORT CONVECTION MOVING INTO OUR
NORTHWESTERN ZONES LATER THIS MORNING. CURRENTLY...CONVECTION HAS
MOVED INTO FAR WESTERN TN. THUS...POPS OF 30-50 PERCENT FOR
TODAY...GREATEST POPS WEST.
TONIGHT...COLD FRONT GETS A LITTLE CLOSER BUT AGAIN...THE BETTER MCS
COMPLEXES WILL REMAIN NW OF MIDDLE TN. MAY SEE SOME CONVECTIVE
ENCROACHMENT ON OUR FAR NW AREAS LATE TONIGHT AND WILL THUS INCLUDE
40 POPS NW...20 POPS ELSEWHERE.
ON SATURDAY...COLD FRONT WILL APPROACH THE MS RIVER BY LATE
AFTERNOON. MOISTURE AND INSTABILITY WILL BE RAMPING UP ACROSS THE
MID STATE AND POPS OF 30-60 PERCENT WILL BE ON ORDER. THE OVERALL
SYSTEM WILL BECOME MORE SFC ORIENTED AS THE MID AND UPPER JETS
REMAIN NORTH OF TN. NEVERTHELESS..FRONTAL IMPACTS WILL BE
FELT...ESPECIALLY ON SATURDAY NIGHT AND SUNDAY...WITH THE FROPA
OCCURRING ON SUNDAY.
AS FOR SEVERE CHANCES...ELEVATED CAPES WILL CONVERGE WITH FRONTAL
BASED SFC FORCING TO PROMOTE A SLIGHT RISK OF SEVERE ON SATURDAY AFT
AND EVENING...MAINLY WESTERN ZONES. THEN...AS THE FRONT MOVES
THROUGH ON SUNDAY...SEVERE WEATHER WILL BE POSSIBLE ACROSS EASTERN
ZONES DURING THE DAY. NOT REALLY SEEING MUCH OVERNIGHT SEVER WEATHER
POTENTIAL...UPPER DYNAMICS ARE LOOKING WEAKER AND 850 MB FLOW IS NOT
OVERLY IMPRESSIVE. DESCENT QPF TOTALS FOR THE SAT NT
OVERNIGHT...BUT OVERALL STORM DEINTENSIFICATION MAY BE THE RULE AS
WE LOSE THE DAYTIME HEATING AND THE ELEVATED DYNAMICS ARE NOT
OVERLY IMPRESSIVE.
AS FOR HEAVY RAINFALL POTENTIAL...LOOKS LIKE STORM TOTAL QPF OF UP
TO 2 INCHES IS POSSIBLE NW AREAS...1 TO 2 INCHES ELSEWHERE. THIS IS
NOT ESF WORTHY...BUT IT WILL CONTINUE TO BE MONITORED.
TEMPERATURE WISE...NO BIG DEVIATIONS VERSUS THE MAV.
IN THE EXT FCST...BOUNDARY MOVES THROUGH WITH DRIER POP FREE WEATHER
FOR THE EARLY HALF OF THE WORK WEEK. MOISTURE...HOWEVER...WILL
RETURN AS THE SFC HIGH SHIFTS EAST AND ALLOWS A SOUTHERLY LOW LEVEL
FLOW TO RETURN. TEMPS THROUGH THE EXTENDED ARE LOOKING SEASONAL.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
01
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
948 AM CDT FRI MAY 31 2013
.UPDATE...
LATEST RADAR AND IR SATELLITE IMAGERY DEPICTS A WEAKENING MCS
OVER WESTERN ZONES WITH SHOWERS AND STORMS DIMINISHING IN
COVERAGE AND CLOUD TOPS WARMING SIGNIFICANTLY. ALTHOUGH HRRR
INDICATES ACTIVITY WILL CONTINUE MARCHING EASTWARD THROUGH THE
CWA...APPEARS MUCH OF THE CURRENT PRECIP WILL DISSIPATE PRIOR TO
REACHING THE I-65 CORRIDOR. NEVERTHELESS...VERY MOIST AIRMASS IN
PLACE SHOWN BY THE PWAT OF 1.67 INCHES ON THE 12Z OHX SOUNDING
ALONG WITH CONTINUED DAYTIME HEATING SHOULD SPAWN ADDITIONAL
SCATTERED SHOWERS AND STORMS AHEAD OF DYING MCS LATER TODAY. HAVE
RAISED POPS ACROSS CENTRAL AND WESTERN ZONES FOR THE MORNING HOURS
BASED ON CURRENT TRENDS...AND BUMPED UP CLOUD COVER AND LOWERED
HIGH TEMPS IN THE NORTHWEST. REST OF FORECAST REMAINS UNCHANGED.
SHAMBURGER
&&
.PREV DISCUSSION... /ISSUED 831 AM CDT FRI MAY 31 2013/
AVIATION UPDATE...
GOOD ROUND OF SHOWERS AND STORMS OVER WESTERN TENNESSEE HAVE
MOVED INTO NORTHWEST TENNESSEE WITH ISOLATED RENEGADE SHOWERS
FIXING TO MOVE INTO DAVIDSON COUNTY. H-TRIPLE-R DRIVE SHOWERS AND
STORMS CURRENTLY IN WEST TENNESSEE EASTWARD AS WE GO THROUGH THE
MORNING HOURS.
INFRARED SATELLITE LOOP SHOW TOPS WARMING ACROSS WESTERN TENNESSEE
WITH LIGHTNING STRIKES DECREASING.
BOYD
PREV DISCUSSION... /ISSUED 622 AM CDT FRI MAY 31 2013/
UPDATE...FOR 12Z AVIATION DISCUSSION.
AVIATION...12Z AVIATION DISCUSSION.
UNCERTAINTIES...HOW FAR WILL MOISTURE ASSOCIATED WITH DYING MCS MAKE IT INTO
MID STATE AND ASSOCIATED SHWR/TSTMS CHANCES. WILL GO WITH VFR CEILINGS THRU
01/12Z...WITH MAIN IMPACT OF SHWRS/TSTMS ACROSS CKV FROM 31/13Z-31/18Z. QUESTION
HOW FAR EWD MCS INFLUENCES WILL EXTEND...AND THUS WILL CONTINUE WITH ONLY
VCTS REMARKS AT BOTH BNA/CSV. EXPECT SOME ERROSION OF VFR CU CEILINGS AFTER
31/18Z W TO 31/22Z E...WITH AN INCREASE IN MOISTURE AHEAD OF UPPER LEVEL
DISTURBANCE ALLOWING FOR SCT/BKN STCU/AC/CI FROM 01/07Z W TO 01/12Z E. PER SFC
PRESSURE GRADIENT...EXPECT GUST TO 20KTS POSSIBLE 31/13Z W TO 01/03Z E.
PREV DISCUSSION.../ISSUED 554 AM CDT FRI MAY 31 2013/
UPDATE...
LATEST MODELS INDICATING THAT THE DEEPER MOISTURE WILL INDEED
TRANSITION NORTHEASTWARD ACROSS OUR NORTHWESTERN COUNTIES LATER
THIS MORNING. THIS IS FURTHER CONFIRMED BY RECENT RADAR TRENDS AND
TODAY`S HRRR DATA. WILL GO AHEAD AND INCREASE POPS...PRIMARILY
ACROSS WESTERN AND NORTH CENTRAL ZONES.
PREV DISCUSSION... /ISSUED 333 AM CDT FRI MAY 31 2013/
MAIN COLD FRONTAL BOUNDARY IS STILL LOCATED WELL WEST OF TN AND
RESIDES ALONG THE CENTRAL PLAINS. MAIN FOCUS OF CONVECTION THIS
MORNING IS IN ASSOCIATION WITH A SERIES OF MCS`S FROM AR NE THROUGH
NRN IN. 850MB JET IS COMBINING WITH STRONG IMPULSES WITHIN THE SWLY
FLOW ALOFT TO KEEP THIS CONVECTION GOING OVERNIGHT. MODELS DO SHOW
AN EASTWARD MIGRATION OF THESE DYNAMICS FOR TODAY. ALTHOUGH THE
DYNAMICS WILL WEAKEN...HRRR DOES SUPPORT CONVECTION MOVING INTO OUR
NORTHWESTERN ZONES LATER THIS MORNING. CURRENTLY...CONVECTION HAS
MOVED INTO FAR WESTERN TN. THUS...POPS OF 30-50 PERCENT FOR
TODAY...GREATEST POPS WEST.
TONIGHT...COLD FRONT GETS A LITTLE CLOSER BUT AGAIN...THE BETTER MCS
COMPLEXES WILL REMAIN NW OF MIDDLE TN. MAY SEE SOME CONVECTIVE
ENCROACHMENT ON OUR FAR NW AREAS LATE TONIGHT AND WILL THUS INCLUDE
40 POPS NW...20 POPS ELSEWHERE.
ON SATURDAY...COLD FRONT WILL APPROACH THE MS RIVER BY LATE
AFTERNOON. MOISTURE AND INSTABILITY WILL BE RAMPING UP ACROSS THE
MID STATE AND POPS OF 30-60 PERCENT WILL BE ON ORDER. THE OVERALL
SYSTEM WILL BECOME MORE SFC ORIENTED AS THE MID AND UPPER JETS
REMAIN NORTH OF TN. NEVERTHELESS..FRONTAL IMPACTS WILL BE
FELT...ESPECIALLY ON SATURDAY NIGHT AND SUNDAY...WITH THE FROPA
OCCURRING ON SUNDAY.
AS FOR SEVERE CHANCES...ELEVATED CAPES WILL CONVERGE WITH FRONTAL
BASED SFC FORCING TO PROMOTE A SLIGHT RISK OF SEVERE ON SATURDAY AFT
AND EVENING...MAINLY WESTERN ZONES. THEN...AS THE FRONT MOVES
THROUGH ON SUNDAY...SEVERE WEATHER WILL BE POSSIBLE ACROSS EASTERN
ZONES DURING THE DAY. NOT REALLY SEEING MUCH OVERNIGHT SEVER WEATHER
POTENTIAL...UPPER DYNAMICS ARE LOOKING WEAKER AND 850 MB FLOW IS NOT
OVERLY IMPRESSIVE. DESCENT QPF TOTALS FOR THE SAT NT
OVERNIGHT...BUT OVERALL STORM DEINTENSIFICATION MAY BE THE RULE AS
WE LOSE THE DAYTIME HEATING AND THE ELEVATED DYNAMICS ARE NOT
OVERLY IMPRESSIVE.
AS FOR HEAVY RAINFALL POTENTIAL...LOOKS LIKE STORM TOTAL QPF OF UP
TO 2 INCHES IS POSSIBLE NW AREAS...1 TO 2 INCHES ELSEWHERE. THIS IS
NOT ESF WORTHY...BUT IT WILL CONTINUE TO BE MONITORED.
TEMPERATURE WISE...NO BIG DEVIATIONS VERSUS THE MAV.
IN THE EXT FCST...BOUNDARY MOVES THROUGH WITH DRIER POP FREE WEATHER
FOR THE EARLY HALF OF THE WORK WEEK. MOISTURE...HOWEVER...WILL
RETURN AS THE SFC HIGH SHIFTS EAST AND ALLOWS A SOUTHERLY LOW LEVEL
FLOW TO RETURN. TEMPS THROUGH THE EXTENDED ARE LOOKING SEASONAL.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
831 AM CDT FRI MAY 31 2013
.MESOSCALE AND AVIATION UPDATE...
GOOD ROUND OF SHOWERS AND STORMS OVER WESTERN TENNESSEE HAVE MOVED
INTO NORTHWEST TENNESSEE WITH ISOLATED RENEGADE SHOWERS FIXING TO
MOVE INTO DAVIDSON COUNTY. H-TRIPLE-R DRIVE SHOWERS AND STORMS
CURRENTLY IN WEST TENNESSEE EASTWARD AS WE GO THROUGH THE MORNING HOURS.
INFRARED SATELLITE LOOP SHOW TOPS WARMING ACROSS WESTERN TENNESSEE
WITH LIGHTNING STRIKES DECREASING.
BOYD
&&
.PREV DISCUSSION... /ISSUED 622 AM CDT FRI MAY 31 2013/
UPDATE...FOR 12Z AVIATION DISCUSSION.
AVIATION...12Z AVIATION DISCUSSION.
UNCERTAINTIES...HOW FAR WILL MOISTURE ASSOCIATED WITH DYING MCS MAKE IT INTO
MID STATE AND ASSOCIATED SHWR/TSTMS CHANCES. WILL GO WITH VFR CEILINGS THRU
01/12Z...WITH MAIN IMPACT OF SHWRS/TSTMS ACROSS CKV FROM 31/13Z-31/18Z. QUESTION
HOW FAR EWD MCS INFLUENCES WILL EXTEND...AND THUS WILL CONTINUE WITH ONLY
VCTS REMARKS AT BOTH BNA/CSV. EXPECT SOME ERROSION OF VFR CU CEILINGS AFTER
31/18Z W TO 31/22Z E...WITH AN INCREASE IN MOISTURE AHEAD OF UPPER LEVEL
DISTURBANCE ALLOWING FOR SCT/BKN STCU/AC/CI FROM 01/07Z W TO 01/12Z E. PER SFC
PRESSURE GRADIENT...EXPECT GUST TO 20KTS POSSIBLE 31/13Z W TO 01/03Z E.
PREV DISCUSSION.../ISSUED 554 AM CDT FRI MAY 31 2013/
UPDATE...
LATEST MODELS INDICATING THAT THE DEEPER MOISTURE WILL INDEED
TRANSITION NORTHEASTWARD ACROSS OUR NORTHWESTERN COUNTIES LATER
THIS MORNING. THIS IS FURTHER CONFIRMED BY RECENT RADAR TRENDS AND
TODAY`S HRRR DATA. WILL GO AHEAD AND INCREASE POPS...PRIMARILY
ACROSS WESTERN AND NORTH CENTRAL ZONES.
PREV DISCUSSION... /ISSUED 333 AM CDT FRI MAY 31 2013/
MAIN COLD FRONTAL BOUNDARY IS STILL LOCATED WELL WEST OF TN AND
RESIDES ALONG THE CENTRAL PLAINS. MAIN FOCUS OF CONVECTION THIS
MORNING IS IN ASSOCIATION WITH A SERIES OF MCS`S FROM AR NE THROUGH
NRN IN. 850MB JET IS COMBINING WITH STRONG IMPULSES WITHIN THE SWLY
FLOW ALOFT TO KEEP THIS CONVECTION GOING OVERNIGHT. MODELS DO SHOW
AN EASTWARD MIGRATION OF THESE DYNAMICS FOR TODAY. ALTHOUGH THE
DYNAMICS WILL WEAKEN...HRRR DOES SUPPORT CONVECTION MOVING INTO OUR
NORTHWESTERN ZONES LATER THIS MORNING. CURRENTLY...CONVECTION HAS
MOVED INTO FAR WESTERN TN. THUS...POPS OF 30-50 PERCENT FOR
TODAY...GREATEST POPS WEST.
TONIGHT...COLD FRONT GETS A LITTLE CLOSER BUT AGAIN...THE BETTER MCS
COMPLEXES WILL REMAIN NW OF MIDDLE TN. MAY SEE SOME CONVECTIVE
ENCROACHMENT ON OUR FAR NW AREAS LATE TONIGHT AND WILL THUS INCLUDE
40 POPS NW...20 POPS ELSEWHERE.
ON SATURDAY...COLD FRONT WILL APPROACH THE MS RIVER BY LATE
AFTERNOON. MOISTURE AND INSTABILITY WILL BE RAMPING UP ACROSS THE
MID STATE AND POPS OF 30-60 PERCENT WILL BE ON ORDER. THE OVERALL
SYSTEM WILL BECOME MORE SFC ORIENTED AS THE MID AND UPPER JETS
REMAIN NORTH OF TN. NEVERTHELESS..FRONTAL IMPACTS WILL BE
FELT...ESPECIALLY ON SATURDAY NIGHT AND SUNDAY...WITH THE FROPA
OCCURRING ON SUNDAY.
AS FOR SEVERE CHANCES...ELEVATED CAPES WILL CONVERGE WITH FRONTAL
BASED SFC FORCING TO PROMOTE A SLIGHT RISK OF SEVERE ON SATURDAY AFT
AND EVENING...MAINLY WESTERN ZONES. THEN...AS THE FRONT MOVES
THROUGH ON SUNDAY...SEVERE WEATHER WILL BE POSSIBLE ACROSS EASTERN
ZONES DURING THE DAY. NOT REALLY SEEING MUCH OVERNIGHT SEVER WEATHER
POTENTIAL...UPPER DYNAMICS ARE LOOKING WEAKER AND 850 MB FLOW IS NOT
OVERLY IMPRESSIVE. DESCENT QPF TOTALS FOR THE SAT NT
OVERNIGHT...BUT OVERALL STORM DEINTENSIFICATION MAY BE THE RULE AS
WE LOSE THE DAYTIME HEATING AND THE ELEVATED DYNAMICS ARE NOT
OVERLY IMPRESSIVE.
AS FOR HEAVY RAINFALL POTENTIAL...LOOKS LIKE STORM TOTAL QPF OF UP
TO 2 INCHES IS POSSIBLE NW AREAS...1 TO 2 INCHES ELSEWHERE. THIS IS
NOT ESF WORTHY...BUT IT WILL CONTINUE TO BE MONITORED.
TEMPERATURE WISE...NO BIG DEVIATIONS VERSUS THE MAV.
IN THE EXT FCST...BOUNDARY MOVES THROUGH WITH DRIER POP FREE WEATHER
FOR THE EARLY HALF OF THE WORK WEEK. MOISTURE...HOWEVER...WILL
RETURN AS THE SFC HIGH SHIFTS EAST AND ALLOWS A SOUTHERLY LOW LEVEL
FLOW TO RETURN. TEMPS THROUGH THE EXTENDED ARE LOOKING SEASONAL.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
01
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
622 AM CDT FRI MAY 31 2013
.UPDATE...FOR 12Z AVIATION DISCUSSION.
&&
.AVIATION...12Z AVIATION DISCUSSION.
UNCERTAINTIES...HOW FAR WILL MOISTURE ASSOCIATED WITH DYING MCS MAKE IT INTO
MID STATE AND ASSOCIATED SHWR/TSTMS CHANCES. WILL GO WITH VFR CEILINGS THRU
01/12Z...WITH MAIN IMPACT OF SHWRS/TSTMS ACROSS CKV FROM 31/13Z-31/18Z. QUESTION
HOW FAR EWD MCS INFLUENCES WILL EXTEND...AND THUS WILL CONTINUE WITH ONLY
VCTS REMARKS AT BOTH BNA/CSV. EXPECT SOME ERROSION OF VFR CU CEILINGS AFTER
31/18Z W TO 31/22Z E...WITH AN INCREASE IN MOISTURE AHEAD OF UPPER LEVEL
DISTURBANCE ALLOWING FOR SCT/BKN STCU/AC/CI FROM 01/07Z W TO 01/12Z E. PER SFC
PRESSURE GRADIENT...EXPECT GUST TO 20KTS POSSIBLE 31/13Z W TO 01/03Z E.
&&
.PREV DISCUSSION.../ISSUED 554 AM CDT FRI MAY 31 2013/
UPDATE...
LATEST MODELS INDICATING THAT THE DEEPER MOISTURE WILL INDEED
TRANSITION NORTHEASTWARD ACROSS OUR NORTHWESTERN COUNTIES LATER
THIS MORNING. THIS IS FURTHER CONFIRMED BY RECENT RADAR TRENDS AND
TODAY`S HRRR DATA. WILL GO AHEAD AND INCREASE POPS...PRIMARILY
ACROSS WESTERN AND NORTH CENTRAL ZONES.
PREV DISCUSSION... /ISSUED 333 AM CDT FRI MAY 31 2013/
MAIN COLD FRONTAL BOUNDARY IS STILL LOCATED WELL WEST OF TN AND
RESIDES ALONG THE CENTRAL PLAINS. MAIN FOCUS OF CONVECTION THIS
MORNING IS IN ASSOCIATION WITH A SERIES OF MCS`S FROM AR NE THROUGH
NRN IN. 850MB JET IS COMBINING WITH STRONG IMPULSES WITHIN THE SWLY
FLOW ALOFT TO KEEP THIS CONVECTION GOING OVERNIGHT. MODELS DO SHOW
AN EASTWARD MIGRATION OF THESE DYNAMICS FOR TODAY. ALTHOUGH THE
DYNAMICS WILL WEAKEN...HRRR DOES SUPPORT CONVECTION MOVING INTO OUR
NORTHWESTERN ZONES LATER THIS MORNING. CURRENTLY...CONVECTION HAS
MOVED INTO FAR WESTERN TN. THUS...POPS OF 30-50 PERCENT FOR
TODAY...GREATEST POPS WEST.
TONIGHT...COLD FRONT GETS A LITTLE CLOSER BUT AGAIN...THE BETTER MCS
COMPLEXES WILL REMAIN NW OF MIDDLE TN. MAY SEE SOME CONVECTIVE
ENCROACHMENT ON OUR FAR NW AREAS LATE TONIGHT AND WILL THUS INCLUDE
40 POPS NW...20 POPS ELSEWHERE.
ON SATURDAY...COLD FRONT WILL APPROACH THE MS RIVER BY LATE
AFTERNOON. MOISTURE AND INSTABILITY WILL BE RAMPING UP ACROSS THE
MID STATE AND POPS OF 30-60 PERCENT WILL BE ON ORDER. THE OVERALL
SYSTEM WILL BECOME MORE SFC ORIENTED AS THE MID AND UPPER JETS
REMAIN NORTH OF TN. NEVERTHELESS..FRONTAL IMPACTS WILL BE
FELT...ESPECIALLY ON SATURDAY NIGHT AND SUNDAY...WITH THE FROPA
OCCURRING ON SUNDAY.
AS FOR SEVERE CHANCES...ELEVATED CAPES WILL CONVERGE WITH FRONTAL
BASED SFC FORCING TO PROMOTE A SLIGHT RISK OF SEVERE ON SATURDAY AFT
AND EVENING...MAINLY WESTERN ZONES. THEN...AS THE FRONT MOVES
THROUGH ON SUNDAY...SEVERE WEATHER WILL BE POSSIBLE ACROSS EASTERN
ZONES DURING THE DAY. NOT REALLY SEEING MUCH OVERNIGHT SEVER WEATHER
POTENTIAL...UPPER DYNAMICS ARE LOOKING WEAKER AND 850 MB FLOW IS NOT
OVERLY IMPRESSIVE. DESCENT QPF TOTALS FOR THE SAT NT
OVERNIGHT...BUT OVERALL STORM DEINTENSIFICATION MAY BE THE RULE AS
WE LOSE THE DAYTIME HEATING AND THE ELEVATED DYNAMICS ARE NOT
OVERLY IMPRESSIVE.
AS FOR HEAVY RAINFALL POTENTIAL...LOOKS LIKE STORM TOTAL QPF OF UP
TO 2 INCHES IS POSSIBLE NW AREAS...1 TO 2 INCHES ELSEWHERE. THIS IS
NOT ESF WORTHY...BUT IT WILL CONTINUE TO BE MONITORED.
TEMPERATURE WISE...NO BIG DEVIATIONS VERSUS THE MAV.
IN THE EXT FCST...BOUNDARY MOVES THROUGH WITH DRIER POP FREE WEATHER
FOR THE EARLY HALF OF THE WORK WEEK. MOISTURE...HOWEVER...WILL
RETURN AS THE SFC HIGH SHIFTS EAST AND ALLOWS A SOUTHERLY LOW LEVEL
FLOW TO RETURN. TEMPS THROUGH THE EXTENDED ARE LOOKING SEASONAL.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
31
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
554 AM CDT FRI MAY 31 2013
.UPDATE...
LATEST MODELS INDICATING THAT THE DEEPER MOISTURE WILL INDEED
TRANSITION NORTHEASTWARD ACROSS OUR NORTHWESTERN COUNTIES LATER
THIS MORNING. THIS IS FURTHER CONFIRMED BY RECENT RADAR TRENDS AND
TODAY`S HRRR DATA. WILL GO AHEAD AND INCREASE POPS...PRIMARILY
ACROSS WESTERN AND NORTH CENTRAL ZONES.
&&
.PREV DISCUSSION... /ISSUED 333 AM CDT FRI MAY 31 2013/
MAIN COLD FRONTAL BOUNDARY IS STILL LOCATED WELL WEST OF TN AND
RESIDES ALONG THE CENTRAL PLAINS. MAIN FOCUS OF CONVECTION THIS
MORNING IS IN ASSOCIATION WITH A SERIES OF MCS`S FROM AR NE THROUGH
NRN IN. 850MB JET IS COMBINING WITH STRONG IMPULSES WITHIN THE SWLY
FLOW ALOFT TO KEEP THIS CONVECTION GOING OVERNIGHT. MODELS DO SHOW
AN EASTWARD MIGRATION OF THESE DYNAMICS FOR TODAY. ALTHOUGH THE
DYNAMICS WILL WEAKEN...HRRR DOES SUPPORT CONVECTION MOVING INTO OUR
NORTHWESTERN ZONES LATER THIS MORNING. CURRENTLY...CONVECTION HAS
MOVED INTO FAR WESTERN TN. THUS...POPS OF 30-50 PERCENT FOR
TODAY...GREATEST POPS WEST.
TONIGHT...COLD FRONT GETS A LITTLE CLOSER BUT AGAIN...THE BETTER MCS
COMPLEXES WILL REMAIN NW OF MIDDLE TN. MAY SEE SOME CONVECTIVE
ENCROACHMENT ON OUR FAR NW AREAS LATE TONIGHT AND WILL THUS INCLUDE
40 POPS NW...20 POPS ELSEWHERE.
ON SATURDAY...COLD FRONT WILL APPROACH THE MS RIVER BY LATE
AFTERNOON. MOISTURE AND INSTABILITY WILL BE RAMPING UP ACROSS THE
MID STATE AND POPS OF 30-60 PERCENT WILL BE ON ORDER. THE OVERALL
SYSTEM WILL BECOME MORE SFC ORIENTED AS THE MID AND UPPER JETS
REMAIN NORTH OF TN. NEVERTHELESS..FRONTAL IMPACTS WILL BE
FELT...ESPECIALLY ON SATURDAY NIGHT AND SUNDAY...WITH THE FROPA
OCCURRING ON SUNDAY.
AS FOR SEVERE CHANCES...ELEVATED CAPES WILL CONVERGE WITH FRONTAL
BASED SFC FORCING TO PROMOTE A SLIGHT RISK OF SEVERE ON SATURDAY AFT
AND EVENING...MAINLY WESTERN ZONES. THEN...AS THE FRONT MOVES
THROUGH ON SUNDAY...SEVERE WEATHER WILL BE POSSIBLE ACROSS EASTERN
ZONES DURING THE DAY. NOT REALLY SEEING MUCH OVERNIGHT SEVER WEATHER
POTENTIAL...UPPER DYNAMICS ARE LOOKING WEAKER AND 850 MB FLOW IS NOT
OVERLY IMPRESSIVE. DESCENT QPF TOTALS FOR THE SAT NT
OVERNIGHT...BUT OVERALL STORM DEINTENSIFICATION MAY BE THE RULE AS
WE LOSE THE DAYTIME HEATING AND THE ELEVATED DYNAMICS ARE NOT
OVERLY IMPRESSIVE.
AS FOR HEAVY RAINFALL POTENTIAL...LOOKS LIKE STORM TOTAL QPF OF UP
TO 2 INCHES IS POSSIBLE NW AREAS...1 TO 2 INCHES ELSEWHERE. THIS IS
NOT ESF WORTHY...BUT IT WILL CONTINUE TO BE MONITORED.
TEMPERATURE WISE...NO BIG DEVIATIONS VERSUS THE MAV.
IN THE EXT FCST...BOUNDARY MOVES THROUGH WITH DRIER POP FREE WEATHER
FOR THE EARLY HALF OF THE WORK WEEK. MOISTURE...HOWEVER...WILL
RETURN AS THE SFC HIGH SHIFTS EAST AND ALLOWS A SOUTHERLY LOW LEVEL
FLOW TO RETURN. TEMPS THROUGH THE EXTENDED ARE LOOKING SEASONAL.
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 87 70 88 70 / 40 20 40 60
CLARKSVILLE 86 69 86 68 / 50 40 60 80
CROSSVILLE 81 66 82 66 / 30 10 40 40
COLUMBIA 87 70 88 70 / 30 10 40 60
LAWRENCEBURG 86 69 87 69 / 30 10 40 60
WAVERLY 87 70 87 68 / 40 40 60 80
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
731 PM CDT SAT JUN 1 2013
.AVIATION...
SKIES CLEARING ACROSS THE REGION EXCEPT ALONG THE COAST WHERE
1600-2500 FT SCT SKY COVER IS OBSERVED. COLD FRONT MOVING
SOUTHEAST AT 10-11 KNOTS AND CONVECTION HAS BEEN LACKING UNTIL
REACHING THE DEEPER MOISTURE AROUND KTYR AND EASTWARD. A COUPLE OF
STRONG/SEVERE CELLS IN THE WATCH TO THE WEST OF THE AREA.
CONCERNED THAT WITH THE LOSS OF HEATING AND CURRENT CAPPING IN
PLACE THAT ONLY A FEW SHOWERS WILL BE SPREAD OUT ALONG THE FRONTAL
BOUNDARY AND ANY OUTFLOWS WHEN IT GETS INTO SETX TERMINALS. BEST
CHANCES FOR ANY THUNDERSTORMS WILL LIKELY BE IN THE UTS AREA.
PATCHY MVFR CIGS SHOULD RETURN TONIGHT MAINLY 06Z AND BEYOND BUT
WITH THE WINDS RELAXING SHALLOW FOG ALSO AN A DECENT BET. TIMING
OF WIND CHANGE IS VERY PROBLEMATIC AND HAVE GENERALLY GONE WITH A
FEW HOURS OF VRB05KT CLL AROUND 03Z-IAH 09Z-GLS 13Z...THEN
CONSOLIDATING TO NNE WINDS ABOUT 4 HOURS LATER. RAIN CHANCES LOOK
SLIM TOMORROW WITH THE ABUNDANCE OF DRIER AIR...IF ANY PRECIP
DEVELOPS IN THE AFTERNOON IT WILL LIKELY HOLD OFF UNTIL SEABREEZE
FIGHTS ITS WAY INLAND AFTER 21Z.
45
&&
.PREV DISCUSSION... /ISSUED 304 PM CDT SAT JUN 1 2013/
DISCUSSION...
AT 19Z...A COLD FRONT EXTENDED FROM ABOUT PARIS TO BROWNWOOD TO
MIDLAND. A WEAK TROUGH OF LOW PRESSURE EXTENDED FROM TEXARKANA TO
ABOUT HUNTSVILLE. THE FRONT WILL CONTINUE TO SLIDE SOUTH TOWARD SE
TX OVERNIGHT. NAM 12 FCST SOUNDINGS SHOW PW VALUES APPROACHING
2.00 INCHES AT KCLL AND AROUND 1.8 INCHES AT KIAH WITH LITTLE TO
NO CAPPING. DEEP LAYER MOISTURE AND MODEST SURFACE CONVERGENCE
SHOULD YIELD A GOOD CHANCE OF RAIN OVER THE NORTH TONIGHT.
CONFIDENCE IS LESS CERTAIN OVER THE SOUTHERN HALF OF THE CWA AS
SURFACE CONVERGENCE WEAKENS CONSIDERABLY AFTER MIDNIGHT. WILL GO
WITH LIKELY POPS OVER THE NORTH AND TAPER TO LOW END CHANCE POPS
CENTRAL AND SLIGHT CHANCE ALONG THE COAST. THE RAP INITIALIZED
WELL SO WILL LEAN TOWARD THE RAP AND OTHER HI-RES MODELS IN THE
SHORT TERM. THERE COULD BE SOME TRAINING OF STORMS OVER THE NORTH
TONIGHT AND AM A BIT CONCERNED THAT SOME HEFTY RAINFALL TOTALS
WILL BE POSSIBLE NORTH OF A BRENHAM TO TRINITY LINE. WILL REISSUE
THE HWO TO HIGHLIGHT THIS POSSIBILITY.
MOISTURE LEVELS WANE QUICKLY SUNDAY MORNING. UPPER LEVEL JET
ENERGY LOOKS NEUTRAL WITH UPPER LEVEL CONVERGENCE INCREASING
DURING SUNDAY AFTN. WILL TRIM POPS FOR SUNDAY AND END ALL RAIN
CHANCES BY SUNDAY EVENING. IT STILL LOOKS WARM ON SUNDAY WITH MAX
TEMPS NEAR 90 DEGREES. UPPER LEVEL RIDGING TRIES TO BUILD INTO
SOUTH TEXAS EARLY NEXT WEEK. WENT CLOSER TO THE WARMER EUROPEAN
GUIDANCE. MODELS DIVERGE A BIT TOWARD NEXT WEEKEND. THE ECMWF IS
STRONGER WITH SOME S/WV ENERGY ON FRIDAY AND DEEPER WITH AN UPPER
LEVEL TROUGH ON SUNDAY. THE GFS AND CANADIAN LOOK SOMEWHAT SIMILAR
TO THE ECMWF BUT WEAKER. THE GRIDS HAVE 20 POPS FOR FRI/SAT AND
FEEL THAT IS A GOOD PLACE TO START. WILL WAIT AND SEE IF MODELS
CAN BUILD A CONSENSUS FOR HIGHER RAIN CHANCES.
MARINE...
WILL ALLOW THE RIP CURRENT STATEMENT TO EXPIRE AT 00Z AS WINDS
CONTINUE TO RELAX. LIGHT EAST TO SOUTHEAST WINDS WILL BE THE NORM
THROUGH THE MAJORITY OF NEXT WEEK. THE LACK OF ANY SIGNIFICANT
PRESSURE GRADIENT...DUE TO NORTH-NORTHEASTERN CENTERED SURFACE
RIDGING...WILL MAINTAIN A TAME MARITIME WIND FIELD.
GENERALLY...SEAS HEIGHTS WILL BE AN AVERAGE 2 TO 3 FEET. THERE IS
A POSSIBILITY OF A LATE WEEK FAR OFFSHORE SWELL. THIS WILL BE
DEPENDENT UPON THE DEVELOPMENT AND EVOLUTION OF AN EASTERN GULF
TROUGH OF LOW PRESSURE. 31
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 72 90 66 91 70 / 60 20 10 0 0
HOUSTON (IAH) 75 91 67 92 70 / 40 30 10 0 0
GALVESTON (GLS) 78 87 74 87 76 / 20 30 10 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...38
AVIATION/MARINE...45
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
344 PM CDT FRI MAY 31 2013
.TONIGHT...
INSTABILITY WAS HIGH ACROSS WEST CENTRAL TEXAS WITH RAP ML CAPES
EXCEEDING 5000 J/KG. A STRONG CAP HOWEVER WAS PREVENTING STORM
DEVELOPMENT. I DID ADD A SLIGHT CHANCE OF THUNDERSTORMS IN HASKELL
AND THROCKMORTON COUNTIES THIS EVENING...WHERE A CUMULUS FIELD WAS
BEGINNING TO DEVELOP IN AN AREA OF WEAK SURFACE CONVERGENCE EAST OF
THE DRYLINE. AGAIN...LIKE YESTERDAY...IF STORMS DO DEVELOP...THEY
COULD RAPIDLY BECOME SEVERE WITH LARGE HAIL AND DAMAGING WINDS. A
TORNADO IS ALSO NOT OUT OF QUESTION WITH VERY STRONG INSTABILITY
PRESENT.
OTHERWISE A WARM NIGHT WITH LOW LEVEL MOISTURE CONTINUING TO
FLOW FROM THE GULF MEXICO. STRATUS RETURNS AFTER MIDNIGHT...FROM THE
HILL COUNTRY. 850 MB LOW LEVEL JET AGAIN PICKS UP TO 45-50 KTS
TOWARD MIDNIGHT. PERSISTENCE FORECAST TONIGHT WITH LOWS IN THE LOWER
TO MID 70S.
.SATURDAY AND SUNDAY...
AS THE FRONT PUSHES SOUTH ACROSS THE AREA SATURDAY MORNING...THINGS
SHOULD STAY RELATIVELY QUITE. WITH DAYTIME HEATING AND DEWPOINTS
AROUND 70 DEGREES...SURFACE BASED CAPE WILL INCREASE TO AROUND 3500
J/KG BY MID AFTERNOON. WITH THE FORCING FROM THE FRONT...REALIZING
THIS INSTABILITY SHOULD NOT BE A PROBLEM. THE CIN VALUES ARE
REASONABLE...HIGH ENOUGH TO ALLOW THE INSTABILITY TO BUILD...BUT NOT
TOO MUCH TO KEEP ANY OF IT FROM BEING RELEASED. SHEAR WILL NOT BE
SPECTACULAR...BUT WITH 30 KTS THERE WILL BE ENOUGH FOR SUPPORT
VIGOROUS UPDRAFTS. THE MAIN THREAT WILL BE VERY LARGE HAIL. LOW
LEVEL SHEAR IS LACKLUSTER...ONLY MAYBE 10 KTS...SO THE TORNADO
THREAT SHOULD BE LIMITED...THOUGH IT CANNOT BE RULED OUT. IF A STORM
CAN STAY ALONG THE BOUNDARY FOR LONG ENOUGH...IT WILL BE POSSIBLE
FOR A CIRCULATION TO DEVELOP. THE MAIN AREA OF CONCERN IS THE
SOUTHEASTERN PART OF THE AREA...SOUTH OF A LINE FROM BROWNWOOD...TO
SAN ANGELO...TO OZONA. OTHERWISE...TEMPERATURES WILL COOL OFF A
LITTLE FROM FRIDAY BEHIND THE FRONT. HIGHS WILL GENERALLY BE IN THE
UPPER 80S TO LOWER 90S FOR SATURDAY AND SUNDAY. LOWS WILL IN THE 60S
TO LOWER 70S. RAIN CHANCES SHOULD MOVE OUT BY EARLY AFTERNOON ON
.SUNDAY NIGHT THROUGH FRIDAY...
RIDGE OF HIGH PRESSURE IN THE MID AND UPPER LEVELS ACROSS THE
ATMOSPHERE WILL BECOME ESTABLISHED FOR AT LEAST THE FIRST HALF OF
NEXT WEEK. TEMPERATURES WILL LIKELY SOAR WITH THE RIDGE...WITH THE
LOCATION OF THE THERMAL RIDGE SUGGESTING THAT READINGS AT LEAST
NEAR THE 100 DEGREE MARK ARE POSSIBLE FOR THE WESTERN HALF OF THE AREA.
THE GFS WEAKENS THE RIDGE FOR THE LAST HALF OF THE
WEEK...AND TRIES ANOTHER FRONT AND CONVECTION INTO THE ARE FOR
THURSDAY OR FRIDAY. ECMWF SHOWS A LITTLE MORE PERSISTENT
RIDGE...AND DELAYS ANY CONVECTION TIL FRIDAY. AT THIS
POINT...THINK KEEPING THE FORECAST DRY FOR NOW IS PROBABLY THE
BEST OPTION...AND LET THE UNCERTAINTIES SETTLE A LITTLE.
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 73 90 65 89 66 / 10 20 30 10 10
SAN ANGELO 74 93 71 91 69 / 5 30 30 20 10
JUNCTION 73 94 70 92 68 / 5 30 40 20 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
04/NR/07
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1241 PM EDT FRI MAY 31 2013
.SYNOPSIS...
HIGH PRESSURE WILL KEEP US IN THE SUMMER LIKE HEAT INTO
SATURDAY. BY THE END OF THE WEEKEND INTO EARLY NEXT WEEK A
FRONTAL SYSTEM WILL ARRIVE WITH INCREASING CHANCES OF
SHOWERS AND STORMS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 925 AM EDT FRIDAY...
OVERALL PERSISTENCE FORECAST IN STORE THRU THIS AFTERNOON WITH
LITTLE CHANGE SEEN ALOFT OFF MORNING SOUNDINGS WHILE PWATS HAVE
INCREASED A BIT FROM YDA. HOWEVER FOCUS REMAINS LIMITED GIVEN DRY
AIR LINGERING ALOFT UNDER THE CONTINUED 5H RIDGING AND SURFACE
HIGH PRESSURE EXTENDING FROM OFFSHORE. HEIGHTS DO FALL A LITTLE
THIS AFTERNOON AS MODIFIED CAPES BOUNCE ABOVE 1500-2000 J/KG AND
WEAK CONVERGENCE DEVELOPS FAR NW PER SOUTH/SE FLOW. ALSO SOME WEAK
MCON LOOKS TO TAKE SHAPE IN THE MORE MOIST LOW LEVEL WEAK RETURN
FLOW ACROSS THE FAR SOUTH BUT IFFY WITH COVERAGE AND IF ANY SHRA
WILL MAKE IT THIS FAR NORTH. OTRW LATEST HRRR AND RNK-WRF SHOWING
VERY ISOLATED COVERAGE MAINLY FAR NW LATER THIS AFTERNOON SO
KEEPING A 20/30 POP MENTION GOING DOWN ALONG THE WESTERN SPINE OF
THE APPS AND LITTLE ELSW. 12Z THICKNESS CLOSE TO THAT OF THU AND
GIVEN SIMILAR 85H TEMPS BUMPED UP HIGHS A FEW DEGREES WITH VALUES
AGAIN APPROACHING 90 SE.
TONIGHT...CONVECTION WEAKENS/ENDS ACROSS THE WEST AND WILL SEE
ANOTHER RIDE UP CLOSE TO THE SRN BLUE RIDGE AND ADJACENT AREAS OF
SOME LOWER CLOUDS BUT OVERALL PARTLY CLOUDY. MUGGY LOWS IN THE
UPPER 50S TO MID 60S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
AS OF 300 AM EDT THURSDAY...
BERMUDA RIDGING ACROSS THE SOUTHEAST AND MID ATLANTIC STATES WILL BE
STRONG ON FRIDAY...RESULTING IN ONLY AN ISOLATED CHANCE OF SHOWERS
AND THUNDERSTORMS WITH AFTERNOON HEATING...AND HIGHS REACHING THE
MID TO UPPER 80S MOST LOCATIONS. HOWEVER...WILL SEE A TREND WHERE
THE RIDGING PATTERN WILL GRADUALLY BREAK DOWN DURING THE WEEKEND AS
AN UPPER TROUGH SWINGS FROM THE NORTHERN PLAINS ON SATURDAY OVER THE
GREAT LAKES BY SUNDAY. AS SUCH...SHOWER AND THUNDERSTORM ACTIVITY
WILL BE WIDELY SCATTERED ACROSS THE MOUNTAINS ON SATURDAY...AND THEN
RATHER WIDESPREAD ACROSS THE MOUNTAINS ON SUNDAY AS A COLD FRONT
ASSOCIATED WITH THE UPPER TROUGH APPROACHES FROM THE WEST. THE COLD
FRONT IS EXPECTED TO PASS SLOWLY ACROSS OUR AREA SUNDAY NIGHT INTO
MONDAY.
DESPITE THE BREAKDOWN IN RIDGING...AFTERNOON TEMPERATURES FOR
SATURDAY AND SUNDAY WILL NOT FALL OFF MUCH AT ALL...RANGING FROM THE
MID 80S WEST TO NEAR 90 EAST FOR HIGHS BOTH DAYS. OVERNIGHT
TEMPERATURES WILL ALSO REMAIN WARM AND MUGGY THANKS TO THE MOIST
SOUTHWESTERLY WIND FLOW DURING THE PERIOD...WITH LOWS FALLING INTO
THE 60S MOST LOCATIONS.
WILL ALSO KEEP AN EYE OUT FOR PATCHY FOG EARLY EACH MORNING...MAINLY
IN THE RIVER VALLEYS AND ACROSS LOCATIONS WHICH RECEIVED SIGNIFICANT
RAINFALL FROM SHOWER AND THUNDERSTORM ACTIVITY THE EVENING BEFORE.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 300 AM EDT THURSDAY...
BLOCKING PATTERN CONTINUES TO RELAX ON MONDAY AS MID CONUS TROUGH
LIFTS NORTHEAST THROUGH THE GREAT LAKES AND INTO NEW ENGLAND. THIS
WILL ALLOW THE ACCOMPANYING SURFACE FRONT TO MOVE EAST CROSSING THE
MID ATLANTIC REGION. THE ECMWF IS THE MOST PROGRESSIVE MODEL WITH
THIS FEATURE...MOVING IT THROUGH OUR AREA AND OFF THE MID ATLANTIC
COAST MONDAY NIGHT. THE GFS IS ABOUT 12 HOURS SLOWER. PREFER THE
MORE PROGRESSIVE GUIDANCE WITH THE SURFACE FRONT WELL EAST OF THE
FORECAST AREA BY DAYBREAK TUESDAY. FOLLOWING THIS GUIDANCE...SHOWERS
AND STORMS ARE EXPECTED TO BECOME MORE NUMEROUS...MORE SO FOR MONDAY
AS THE ACTUAL SURFACE FRONT CROSSES THE MID ATLANTIC REGION.
WITH THE FRONTAL PASSAGE PROGGED FOR MONDAY...LOOKING AT RETURN OF
DRY WEATHER FOR TUESDAY AND THE MIDDLE OF NEXT WEEK...HIGH PRESSURE
SLIDING EAST ACROSS THE GREAT LAKES AND PROVIDING US WITH A SOMEWHAT
COOLER NORTHERLY FLOW. AIRMASS BEHIND THIS FRONT IS NOT NEARLY AS
COOL AS WHAT TRANSPIRED OVER THE MEMORIAL DAY HOLIDAY WEEKEND...85H
TEMPS ONLY DROPPING TO AROUND +8 TO +10 DEG C.
RETURN FLOW SHOULD DEVELOP FOR THE LATTER HALF OF NEXT WEEK...WINDS
BECOMING SOUTHERLY ON THE BACK SIDE OF THE SURFACE
HIGH...TEMPERATURES WARMING.
THIS WEEKEND IS THE OFFICIAL START OF THE 2013 HURRICANE SEASON.
EXPECTATIONS ARE FOR AN ABOVE NORMAL SEASON. THIS IS BASED ON SEA
SURFACE TEMPERATURES THAT ARE WARMER THAN NORMAL IN THE TROPICAL
ATLANTIC AND AN ENSO NEUTRAL PATTERN IN THE PACIFIC. THESE FACTORS,
ALONG WITH OTHER HEMISPHERIC DECADAL AND INTER-SEASONAL OSCILLATIONS
ARE SIGNALS FOR AN ACTIVE STORM SEASON. LONG TRACKING STORMS WILL BE
MORE COMMON THIS YEAR THAN IN 2012 FAVORING FORMATION IN THE
INTERTROPICAL CONVERGENCE ZONE. AS SUCH...THE RISK FOR CAT 3, CAT 4,
AND CAT 5 HURRICANES IS GREATER THIS YEAR THAN IN PREVIOUS YEARS.
&&
.AVIATION /16Z FRIDAY THROUGH TUESDAY/...
AS OF 1220 PM EDT FRIDAY...
PREVAILING VFR WILL CONTINUE ACROSS THE REGION THIS AFTERNOON INTO
SATURDAY. HOWEVER SOME CU/TCU WILL FORM THIS AFTERNOON ESPECIALLY
ACROSS THE MOUNTAINS. A FEW COULD FORM INTO SHOWERS OR THUNDERSTORMS
ALTHOUGH COVERAGE STILL LOOKS TO BE SPARSE. KBLF/KLWB STILL STAND
THE BEST CHANCE BUT SINCE SHOULD BE ISOLATED...WILL CONTINUE TO
LEAVE OUT OF THE TAFS.
MOISTURE FETCH WILL AGAIN INCREASE OVERNIGHT SIMILAR TO LAST NIGHT
WITH POTENTIAL TO SEE LOWER CIGS INCLUDING SOME STRATUS SPREAD NE
INTO SOUTHERN PORTIONS OF THE AREA LATE. LATEST NAM AGAIN LATCHES
ON TO THIS SCENARIO BUT WAS OVERDONE FOR THE MOST PART LAST NIGHT
GIVEN DRY AIR IN PLACE. HOWEVER LOW LEVEL MOISTURE RETURN LOOKS A
BIT MORE ROBUST TONIGHT ESPCLY WITH DEWPOINTS ON THE RISE SO PLAN
TO ADD IN A BIT MORE LOW END VFR/MVFR CIGS IN SPOTS TONIGHT.
FOG WILL AGAIN BE AN ISSUE AT KLWB AND PERHAPS KBCB IF THE LOWER
CLOUDS TO DO NOT MOVE IN ALLOWING FOR A PERIOD OF IFR ESPCLY KLWB
TOWARD DAYBREAK SATURDAY. MORNIGN CLOUDS SHOULD BE A BIT MORE
WIDESPREAD SATURDAY ESPCLY MOUNTAINS WITH PERIODIC VFR CU/AC
FIELDS KBCB AND POINTS WEST UNTIL CIGS MIX OUT WITH HEATING IN THE
AFTERNOON. WIDELY SCATTERED CONVECTION ALSO POSSIBLE MAINLY SE
WVA BUT NOT UNTIL LATER SATURDAY SO LEAVING OUT MENTION EARLY ON.
MOISTURE INCREASES EVEN MORE AHEAD OF A FRONT BY LATER SUNDAY AND
INTO EARLY NEXT WEEK. APPEARS SHOWERS AND STORMS WILL BRING SUB
VFR CONDITIONS TO THE REGION DURING THIS TIME WITH BEST CHANCES OF
MVFR/IFR OVER THE MOUNTAIN LOCATIONS SUNDAY AFTERNOON/EVENING AND
OUT EAST INTO MONDAY. FRONT PUSHES SLOWLY SE BY TUESDAY ALLOWING
A RETURN TO MOSTLY VFR BY THEN.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH/WP
NEAR TERM...JH/WP
SHORT TERM...NF
LONG TERM...AMS/NF
AVIATION...JH/KM/WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1015 AM EDT FRI MAY 31 2013
.SYNOPSIS...
HIGH PRESSURE WILL KEEP US IN THE SUMMER LIKE HEAT INTO
SATURDAY. BY THE END OF THE WEEKEND INTO EARLY NEXT WEEK A
FRONTAL SYSTEM WILL ARRIVE WITH INCREASING CHANCES OF
SHOWERS AND STORMS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 925 AM EDT FRIDAY...
OVERALL PERSISTENCE FORECAST IN STORE THRU THIS AFTERNOON WITH
LITTLE CHANGE SEEN ALOFT OFF MORNING SOUNDINGS WHILE PWATS HAVE
INCREASED A BIT FROM YDA. HOWEVER FOCUS REMAINS LIMITED GIVEN DRY
AIR LINGERING ALOFT UNDER THE CONTINUED 5H RIDGING AND SURFACE
HIGH PRESSURE EXTENDING FROM OFFSHORE. HEIGHTS DO FALL A LITTLE
THIS AFTERNOON AS MODIFIED CAPES BOUNCE ABOVE 1500-2000 J/KG AND
WEAK CONVERGENCE DEVELOPS FAR NW PER SOUTH/SE FLOW. ALSO SOME WEAK
MCON LOOKS TO TAKE SHAPE IN THE MORE MOIST LOW LEVEL WEAK RETURN
FLOW ACROSS THE FAR SOUTH BUT IFFY WITH COVERAGE AND IF ANY SHRA
WILL MAKE IT THIS FAR NORTH. OTRW LATEST HRRR AND RNK-WRF SHOWING
VERY ISOLATED COVERAGE MAINLY FAR NW LATER THIS AFTERNOON SO
KEEPING A 20/30 POP MENTION GOING DOWN ALONG THE WESTERN SPINE OF
THE APPS AND LITTLE ELSW. 12Z THICKNESS CLOSE TO THAT OF THU AND
GIVEN SIMILAR 85H TEMPS BUMPED UP HIGHS A FEW DEGREES WITH VALUES
AGAIN APPROACHING 90 SE.
TONIGHT...CONVECTION WEAKENS/ENDS ACROSS THE WEST AND WILL SEE
ANOTHER RIDE UP CLOSE TO THE SRN BLUE RIDGE AND ADJACENT AREAS OF
SOME LOWER CLOUDS BUT OVERALL PARTLY CLOUDY. MUGGY LOWS IN THE
UPPER 50S TO MID 60S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
AS OF 300 AM EDT THURSDAY...
BERMUDA RIDGING ACROSS THE SOUTHEAST AND MID ATLANTIC STATES WILL BE
STRONG ON FRIDAY...RESULTING IN ONLY AN ISOLATED CHANCE OF SHOWERS
AND THUNDERSTORMS WITH AFTERNOON HEATING...AND HIGHS REACHING THE
MID TO UPPER 80S MOST LOCATIONS. HOWEVER...WILL SEE A TREND WHERE
THE RIDGING PATTERN WILL GRADUALLY BREAK DOWN DURING THE WEEKEND AS
AN UPPER TROUGH SWINGS FROM THE NORTHERN PLAINS ON SATURDAY OVER THE
GREAT LAKES BY SUNDAY. AS SUCH...SHOWER AND THUNDERSTORM ACTIVITY
WILL BE WIDELY SCATTERED ACROSS THE MOUNTAINS ON SATURDAY...AND THEN
RATHER WIDESPREAD ACROSS THE MOUNTAINS ON SUNDAY AS A COLD FRONT
ASSOCIATED WITH THE UPPER TROUGH APPROACHES FROM THE WEST. THE COLD
FRONT IS EXPECTED TO PASS SLOWLY ACROSS OUR AREA SUNDAY NIGHT INTO
MONDAY.
DESPITE THE BREAKDOWN IN RIDGING...AFTERNOON TEMPERATURES FOR
SATURDAY AND SUNDAY WILL NOT FALL OFF MUCH AT ALL...RANGING FROM THE
MID 80S WEST TO NEAR 90 EAST FOR HIGHS BOTH DAYS. OVERNIGHT
TEMPERATURES WILL ALSO REMAIN WARM AND MUGGY THANKS TO THE MOIST
SOUTHWESTERLY WIND FLOW DURING THE PERIOD...WITH LOWS FALLING INTO
THE 60S MOST LOCATIONS.
WILL ALSO KEEP AN EYE OUT FOR PATCHY FOG EARLY EACH MORNING...MAINLY
IN THE RIVER VALLEYS AND ACROSS LOCATIONS WHICH RECEIVED SIGNIFICANT
RAINFALL FROM SHOWER AND THUNDERSTORM ACTIVITY THE EVENING BEFORE.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 300 AM EDT THURSDAY...
BLOCKING PATTERN CONTINUES TO RELAX ON MONDAY AS MID CONUS TROUGH
LIFTS NORTHEAST THROUGH THE GREAT LAKES AND INTO NEW ENGLAND. THIS
WILL ALLOW THE ACCOMPANYING SURFACE FRONT TO MOVE EAST CROSSING THE
MID ATLANTIC REGION. THE ECMWF IS THE MOST PROGRESSIVE MODEL WITH
THIS FEATURE...MOVING IT THROUGH OUR AREA AND OFF THE MID ATLANTIC
COAST MONDAY NIGHT. THE GFS IS ABOUT 12 HOURS SLOWER. PREFER THE
MORE PROGRESSIVE GUIDANCE WITH THE SURFACE FRONT WELL EAST OF THE
FORECAST AREA BY DAYBREAK TUESDAY. FOLLOWING THIS GUIDANCE...SHOWERS
AND STORMS ARE EXPECTED TO BECOME MORE NUMEROUS...MORE SO FOR MONDAY
AS THE ACTUAL SURFACE FRONT CROSSES THE MID ATLANTIC REGION.
WITH THE FRONTAL PASSAGE PROGGED FOR MONDAY...LOOKING AT RETURN OF
DRY WEATHER FOR TUESDAY AND THE MIDDLE OF NEXT WEEK...HIGH PRESSURE
SLIDING EAST ACROSS THE GREAT LAKES AND PROVIDING US WITH A SOMEWHAT
COOLER NORTHERLY FLOW. AIRMASS BEHIND THIS FRONT IS NOT NEARLY AS
COOL AS WHAT TRANSPIRED OVER THE MEMORIAL DAY HOLIDAY WEEKEND...85H
TEMPS ONLY DROPPING TO AROUND +8 TO +10 DEG C.
RETURN FLOW SHOULD DEVELOP FOR THE LATTER HALF OF NEXT WEEK...WINDS
BECOMING SOUTHERLY ON THE BACK SIDE OF THE SURFACE
HIGH...TEMPERATURES WARMING.
THIS WEEKEND IS THE OFFICIAL START OF THE 2013 HURRICANE SEASON.
EXPECTATIONS ARE FOR AN ABOVE NORMAL SEASON. THIS IS BASED ON SEA
SURFACE TEMPERATURES THAT ARE WARMER THAN NORMAL IN THE TROPICAL
ATLANTIC AND AN ENSO NEUTRAL PATTERN IN THE PACIFIC. THESE FACTORS,
ALONG WITH OTHER HEMISPHERIC DECADAL AND INTER-SEASONAL OSCILLATIONS
ARE SIGNALS FOR AN ACTIVE STORM SEASON. LONG TRACKING STORMS WILL BE
MORE COMMON THIS YEAR THAN IN 2012 FAVORING FORMATION IN THE
INTERTROPICAL CONVERGENCE ZONE. AS SUCH...THE RISK FOR CAT 3, CAT 4,
AND CAT 5 HURRICANES IS GREATER THIS YEAR THAN IN PREVIOUS YEARS.
&&
.AVIATION /13Z FRIDAY THROUGH TUESDAY/...
AS OF 710 AM EDT FRIDAY...
IFR FOG AT LWB EARLY THIS MORNING WILL BE GONE BY 14Z WITH VFR
CONDITIONS PREVAILING THE REST OF THE DAY AT ALL TAF SITES.
SOME CU/TCU SHOULD FORM THIS AFTERNOON ESPECIALLY ACROSS THE
MOUNTAINS. A FEW COULD FORM INTO THUNDERSTORMS ALTHOUGH COVERAGE
STILL LOOKS TO BE SPARSE. BLF/LWB STAND THE BEST CHANCE BUT GIVEN
NOT BIG A CHANCE...NO MENTION IN THE TAFS.
QUESTION TONIGHT WILL BE THE SOUTHERLY FETCH OF MOISTURE THAT HAS
BEEN SPREADING SOME LOWER CIGS INTO THE NC MOUNTAINS EARLY THIS
MORNING AND IF THEY WILL REACH ACROSS INTO OUR AREA LATE TONIGHT.
THE NAM SEEMS TO INDICATE THAT BCB/DAN COULD SEE SOME CIGS
SCRAPING THE MVFR THRESHOLD LATE TONIGHT...BUT WILL LEAVE IT
SCATTERED AT 3KFT AT BCB AND BKN040 AT DAN. FOG WILL AGAIN BE AN
ISSUE AT LWB AND PERHAPS BCB IF THE LOWER CLOUDS TO DO NOT MOVE
IN.
MOISTURE INCREASES AHEAD OF A FRONT BY LATER SUNDAY AND INTO
EARLY NEXT WEEK. A GOOD CHANCE OF SHOWERS AND STORMS WILL BRING
SOME OCCASIONAL SUB VFR CONDITIONS TO THE REGION DURING THIS TIME.
FRONT PUSHES SLOWLY SE BY TUESDAY ALLOWING A RETURN TO MOSTLY VFR
BY THEN.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH/WP
NEAR TERM...JH/WP
SHORT TERM...NF
LONG TERM...AMS/NF
AVIATION...JH/KM/WP
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1122 AM PDT Fri May 31 2013
.SYNOPSIS...
Most of the region will experience dry conditions today and
Saturday...coupled with warming temperatures. A relatively strong,
but not terribly wet, storm system will bring a cool-down with
some showers and breezy conditions this weekend. A dry and
warming period will greet the new work week with temperatures
increasing into the 80s by Wednesday with dry and warm conditions
rounding out next week.
&&
.DISCUSSION...
Rest of Today...Water vapor imagery was indicating that the slow
moving upper level trough...which brought showers over the past
few days...continued to slowly exit the region this morning.
Drier air behind the trough was now entrenched the entire region
save the northern tip of Idaho. Despite the punch of drier
air...relatively shallow instability and moisture remained fixed
over the northern tier of the forecast area...roughly from the
Okanogan Highlands to the mountains north of Lake Pend Oreille.
This has manifested itself as scattered showers...which thus far
have been largely terrain induced. Based on HRRR forecast data and
model soundings...the instability will remain sufficient for
continued shower formation through the afternoon. However the threat will
gradually decrease from the southwest as upper level ridging builds in
and begins to cap the depth of the convection. Remainder of the
forecast area will see primarily sunny conditions with
temperatures several degrees warmer than yesterday. fx
&&
.AVIATION...
18Z TAFS: VFR conditions expected at all sites through 18z
Saturday. High pressure building in from the southwest will bring
stable conditions to the area and begin to limit the shower threat
over the mountains north of the GEG-COE corridor. For
tonight...the entire region will be precipitation free with mostly
clear skies which will persist into Saturday morning. fx
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 66 45 71 49 67 47 / 0 0 0 30 60 40
Coeur d`Alene 66 42 71 45 66 45 / 0 0 10 30 60 50
Pullman 66 41 71 47 67 44 / 0 0 0 10 30 30
Lewiston 73 46 79 53 74 51 / 0 0 0 10 20 20
Colville 73 42 75 46 69 46 / 20 0 10 50 60 40
Sandpoint 66 39 70 43 66 42 / 20 10 10 30 70 50
Kellogg 61 42 68 47 63 44 / 10 0 0 20 70 50
Moses Lake 74 45 78 50 77 49 / 0 0 0 10 10 10
Wenatchee 73 50 76 52 75 52 / 0 0 0 10 10 0
Omak 73 44 76 46 71 47 / 0 0 20 40 20 10
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1052 PM CDT SAT JUN 1 2013
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.SYNOPSIS...
ISSUED AT 254 PM CDT SAT JUN 1 2013
TURNING COOLER AND LESS HUMID...WITH TEMPERATURES RETURNING TO
SOMEWHAT BELOW NORMAL LEVELS.
UPR PATTERN ACRS NOAM WL TRANSITION BACK INTO A MORE TYPICAL
EARLY SUMMER REGIME AS DEEP UPR TROF OVER THE GREAT LAKES RGN
SHIFTS OFF TO THE NE. IN ITS WAKE...A LOWER AMPLITUDE AND WEAKER
BAND OF WESTERLIES WL REMAIN ACRS THE NRN CONUS. THOUGH INITIALLY
PROGRESSIVE...WEAK UPR TROF WL EVENTUALLY SET-UP OVER THE NRN
PLAINS OR WESTERN LAKES RGN.
THE WARM AND RATHER HUMID AIR STILL LINGERING ACRS THE AREA TDA
WL BE REPLACED BY COOLER AND LESS HUMID CONDITIONS IN THE WAKE OF
THE DEPARTING UPR TROF. TEMPERATURES WL SETTLE BACK TO BLO NORMAL
FOR MOST OF THE REST OF THE PERIOD. THERE WL BE AT LEAST A COUPLE
OPPORTUNITIES TO PICK UP SOME PCPN...SO AMOUNTS WL PROBABLY END UP
NR NORMAL AT MOST LOCATIONS.
&&
.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 254 PM CDT SAT JUN 1 2013
PESKY UPPER LOW THAT HAS BROUGHT SEVERAL DAYS OF UNSETTLED
WEATHER TO THE FORECAST AREA IS FINALLY ON THE MOVE AND WILL SHIFT
EAST ACROSS THE FORECAST AREA OVERNIGHT. THIS WILL FINALLY END THE
SCATTERED SHOWER AND THUNDERSTORM ACTIVITY WE HAVE SEEN THE PAST
FEW DAYS.
NOTABLE INSTABILITY THAT HAS LINGERED ACROSS MAINLY THE EASTERN
HALF OF THE FORECAST AREA...IN CONCERT WITH A WEAK SHORT WAVE
DISTURBANCE MOVING NORTHEAST TOWARD THE FORECAST AREA...HAS
CONTRIBUTED TO A BAND OF SHOWERS AND EMBEDDED THUNDERSTORM
ACTIVITY ACROSS THE FOX VALLY NORTHEAST TOWARD ESCANABA MICHIGAN.
DESPITE FAVORABLE WETBULB ZERO HEIGHTS AROUND 8500 FEET AGL..ONLY
HAVE HAD A COUPLE REPORTS OF SOME PEA SIZE HAIL THUS FAR. WITH PW
VALUES STILL AROUND AN INCH...AND UPPER-LEVEL WINDS CONTINUING TO
WEAKEN AS UPPER TROUGH MOVES OVERHEAD...EXPECT A FEW OF THESE
STORMS TO BE EFFICIENT RAINFALL PRODUCERS PRODUCING SOME BRIEF
HEAVY RAINFALL INTO THE EARLY EVENING. 18Z HRRR AND TO A LESSER
EXTENT THE GFS AND NAM...FOCUS THE BEST LIFT AND ASSOCIATED QPF OVER
THE NORTHEAST PORTION OF THE FORECAST AREA THIS EVENING. THIS SEEMS
REASONABLE GIVEN CURRENT RADAR TRENDS...THUS HAVE ADJUSTED THE QPF
AND POP ACCORDINGLY FOR THIS EVENING. AS UPPER TROUGH SWEEPS
ACROSS THE FORECAST AREA OVERNIGHT...THE ASSOCIATED SURFACE TROUGH
AND SCATTERED SHOWER ACTIVITY WILL ALSO STEADILY PROGRESS
EASTWARD. BASED ON THE LATEST RUN OF THE HRRR...ANTICIPATE THE
SURFACE TROUGH TO MOVE EAST OF THE FOX VALLEY BY AROUND MIDNIGHT.
SOME RESIDUAL LOW-LEVEL MOISTURE IN THE WAKE OF THE SURFACE TROUGH
MAY CONTRIBUTE TO A FEW LINGERING LIGHT SHOWERS OR SPRINKLES OVER
THE LAKE SHORE COUNTIES UNTIL ABOUT 12Z. RESIDUAL LOW LEVEL
MOISTURE REALLY DOES NOT GET SCOURED OUT UNTIL AFTER ABOUT 16Z SO
HAVE SLOWED CLEARING A FEW HOURS ON SUNDAY. BRISK NORTHWEST WINDS
SUNDAY MORNING WILL SLOWLY DIMINISH AS THE DAY PROGRESSES AS
SURFACE HIGH PRESSURE SETTLES IN.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 254 PM CDT SAT JUN 1 2013
HIGH PRESSURE RIDGING SWD FM CANADA WL DOMINATE THE START OF THE
LONG-TERM PERIOD. THAT WL LEAD TO PLENTY OF SUNSHINE AND DRY
CONDITIONS. TEMPS WL FALL WELL BLO NORMAL AT NIGHT. LOOKS LIKE A
PRETTY GOOD CHC OF FROST ACRS THE N SUNDAY NIGHT...AND SOME OF THE
TYPICAL COLD SPOTS COULD EVEN EXPERIENCE A FREEZE. MONDAY NIGHT
MAY NOT BE QUITE AS COLD...BUT AT LEAST PATCHY FROST WL AGAIN BE
POSSIBLE ACRS THE N. WL PROBABLY EVENTUALLY NEED A FROST/FREEZE
HEADLINE FOR THE N FOR SUN NGT...WL HOLD OFF ISSUING THAT NOW AS
LATER FORECASTS HAVE A BETTER CHC OF DISCERNING EXACTLY HOW FAR S
AND E TO TAKE THE HEADLINE.
THE NEXT UPR TROF EMBEDDED IN THE WESTERLIES ACRS THE NRN CONUS
WL BE APPROACHING THE AREA TUE. THE MAJORITY OF THE MODELS DROVE
PCPN WELL E INTO THE FCST AREA DURING THE DAY. BUT IT SEEMS LIKE
DRY AIR WITH THE DEPARTING HIGH PRESSURE SHOULD BE ABLE TO DELAY
THE EWD PROGRESSION OF THE PCPN AT LEAST A LITTLE. SO OPTED TO
KEEP THE MORNING DRY AND THEN LIMIT POPS TO ABOUT THE WRN 1/4 OF
THE FCST AREA DURING THE AFTN.
THE BEST CHC OF PCPN WL COME MID-WK AS THE UPR TROF CROSSES THE
RGN.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1049 PM CDT SAT JUN 1 2013
MAIN UPPER TROF TO MOVE THROUGH EASTERN WI THROUGH FIRST HALF OF
NIGHT. ISOLATED TO SCATTERED SHOWERS NOW MOVING OVER AREA. LOWER
MVFR STRATUS TO MOVE IN FOR PERIOD BEHIND SHOWERS...EXITING SUN
MORNING AS HIGH PRESSURE MOVES IN. GUSTY NORTHWEST WINDS EXPECTED
WITH TROF PASSAGE.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS.......SKOWRONSKI
SHORT TERM.....ESB
LONG TERM......SKOWRONSKI
AVIATION.......TE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1022 PM CDT SAT JUN 1 2013
.SHORT TERM...(TONIGHT AND SUNDAY TONIGHT)
ISSUED AT 218 PM CDT SAT JUN 1 2013
WATER VAPOR IMAGERY SHOWING THE CLOSED LOW SLOWLY FILLING WITH THE
MAIN CIRCULATION CENTER ROTATING EAST ALONG THE MN/IA BORDER. AT THE
SURFACE...LOW PRESSURE WAS CENTERED OVER SOUTHWEST WI WITH A COLD
FRONT/DRYLINE EXTENDING FROM CENTRAL INTO SOUTHWEST WI. STRONGER
CONVECTION WAS FIRING AHEAD OF THE DRYLINE OVER EASTERN WI IN AN
AXIS OF HIGHER DEWPOINT/INSTABILITY AXIS AND 25-35KT 0-3KM BULK
SHEAR. MEANWHILE...RADAR MOSAIC WAS ALSO SHOWING WEAKER
SHOWER/THUNDERSTORM ACTIVITY ENTERING THE FORECAST AREA FROM MN ON
THE EASTERN PERIPHERY OF STEEPER LOW-MID-LEVEL LAPSE RATES UNDER THE
FILLING CLOSED LOW. RAP ANALYSIS SHOWING THIS AREA IN A ZONE OF VERY
WEAK BULK SHEAR...SO JUST EXPECTING MOSTLY SHOWER ACTIVITY WITH
ISOLATED THUNDER OUT OF THIS ACTIVITY. LOOK FOR THIS CONVECTION TO
CONTINUE MOVING INTO THE AREA THROUGH THE REMAINDER OF THIS
AFTERNOON AND INTO TONIGHT AS THE MID-LEVEL TROUGH AXIS MOVES EAST
ACROSS THE REGION. LOOK FOR THE SHOWERS TO DIMINISH AND SKIES TO
CLEAR FROM WEST TO EAST AFTER MIDNIGHT AS SUBSIDENCE/DRYING TAKES
PLACE BEHIND THE DEPARTING TROUGH.
A RIDGE OF HIGH PRESSURE WILL THEN BUILD INTO THE AREA ON SUNDAY FOR
A DRY/MOSTLY SUNNY DAY. DESPITE MOSTLY SUNNY SKIES...COLD AIR
ADVECTION ON NORTHWEST WINDS OF 10-20 MPH WILL YIELD HIGH
TEMPERATURES SOME 10 DEGREES BELOW NORMAL IN THE LOW/MID 60S.
HIGH PRESSURE WILL BE SITUATED OVERHEAD FOR A CLEAR/COOL/CALM SUNDAY
NIGHT. LOOK FOR LOWS RANGING FROM AROUND 40 DEGREES FOR AREAS
ALONG/NORTHEAST OF I-94...TO THE MID/UPPER 40S ELSEWHERE. GIVEN THE
NEARLY SATURATED GROUND AND THE FACT THE HIGH IS OVERHEAD FOR CALM
WINDS...WAS THINKING SOME FOG WOULD BE POSSIBLE. HOWEVER...BUFKIT
SOUNDINGS SHOWING THAT THERE WILL BE PLENTY OF DRYING DURING THE
DAYTIME SUNDAY AND THEN MAINTAIN AT LEAST A 3-5 DEGREE SPREAD
THROUGH THE OVERNIGHT HOURS. WILL THEREFORE LEAVE FOG MENTION
OUT...BUT MAY BE SOMETHING TO KEEP AN EYE ON.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 218 PM CDT SAT JUN 1 2013
LOOK FOR HIGH PRESSURE TO REMAIN IN CONTROL ACROSS THE AREA THROUGH
MONDAY FOR A CONTINUED DRY BREAK FROM THE SOGGY CONDITIONS OF LATE.
LATEST GFS/ECMWF IN FAIRLY GOOD AGREEMENT IN BRINGING A COUPLE WEAK
MID-LEVEL TROUGHS ACROSS THE NORTHERN PLAINS INTO OUR REGION TUESDAY
THROUGH SATURDAY. VERY LITTLE CAPE/INSTABILITY IS INDICATED BY THE
MODELS WHICH WOULD LEAD TO MAINLY SHOWER CHANCES WITH PERHAPS AN
ISOLATED THUNDERSTORM OR TWO. APPEARS THIS PERIOD WILL ALSO CONTINUE
TO BE MARKED BY COOLER THAN NORMAL TEMPERATURE WITH HIGHS GENERALLY
IN THE 60S TO LOWER 70S AND OVERNIGHT LOWS IN THE 50S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1022 PM CDT SAT JUN 1 2013
CEILINGS AND WINDS ARE THE MAIN ISSUE FOR THE FORECAST. MVFR
STRATUS HAS MOVED INTO BOTH TAF SITES IN THE WAKE OF A COLD
FRONTAL PASSAGE. HOWEVER...VFR CEILINGS ARE LURKING UP TO THE
NORTHWEST OVER CENTRAL MINNESOTA WHERE NORTHWEST WINDS ARE
BRINGING DRIER AIR. THEREFORE...ANTICIPATING CEILINGS TO GRADUALLY
CLIMB THROUGH THE MORNING HOURS...BECOMING VFR BY LATE MORNING.
ADDITIONALLY...DAYTIME MIXING AND FURTHER DRYING SHOULD HELP
CLOUDS SCATTER OUT BY NOON. VFR CONDITIONS WILL THEN PERSIST
THROUGH THE EVENING AS HIGH PRESSURE BUILDS INTO THE TAF SITES.
BLUSTERY NORTHWEST WINDS ARE EXPECTED TO PERSIST THROUGH MUCH OF
THE DAY SUNDAY...DIMINISHING LATE IN THE AFTERNOON WITH THE LOSS
OF DAYTIME HEATING AND A WEAKER PRESSURE GRADIENT FROM THE HIGH
BUILDING IN.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
649 PM CDT SAT JUN 1 2013
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE
.SYNOPSIS...
ISSUED AT 254 PM CDT SAT JUN 1 2013
TURNING COOLER AND LESS HUMID...WITH TEMPERATURES RETURNING TO
SOMEWHAT BELOW NORMAL LEVELS.
UPR PATTERN ACRS NOAM WL TRANSITION BACK INTO A MORE TYPICAL
EARLY SUMMER REGIME AS DEEP UPR TROF OVER THE GREAT LAKES RGN
SHIFTS OFF TO THE NE. IN ITS WAKE...A LOWER AMPLITUDE AND WEAKER
BAND OF WESTERLIES WL REMAIN ACRS THE NRN CONUS. THOUGH INITIALLY
PROGRESSIVE...WEAK UPR TROF WL EVENTUALLY SET-UP OVER THE NRN
PLAINS OR WESTERN LAKES RGN.
THE WARM AND RATHER HUMID AIR STILL LINGERING ACRS THE AREA TDA
WL BE REPLACED BY COOLER AND LESS HUMID CONDITIONS IN THE WAKE OF
THE DEPARTING UPR TROF. TEMPERATURES WL SETTLE BACK TO BLO NORMAL
FOR MOST OF THE REST OF THE PERIOD. THERE WL BE AT LEAST A COUPLE
OPPORTUNITIES TO PICK UP SOME PCPN...SO AMOUNTS WL PROBABLY END UP
NR NORMAL AT MOST LOCATIONS.
&&
.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 254 PM CDT SAT JUN 1 2013
PESKY UPPER LOW THAT HAS BROUGHT SEVERAL DAYS OF UNSETTLED
WEATHER TO THE FORECAST AREA IS FINALLY ON THE MOVE AND WILL SHIFT
EAST ACROSS THE FORECAST AREA OVERNIGHT. THIS WILL FINALLY END THE
SCATTERED SHOWER AND THUNDERSTORM ACTIVITY WE HAVE SEEN THE PAST
FEW DAYS.
NOTABLE INSTABLITY THAT HAS LINGERED ACROSS MAINLY THE EASTERN
HALF OF THE FORECAST AREA...IN CONCERT WITH A WEAK SHORT WAVE
DISTURBANCE MOVING NORTHEAST TOWARD THE FORECAST AREA...HAS
CONTRIBUTED TO A BAND OF SHOWERS AND EMBEDDED THUNDERSTORM
ACTIVITY ACROSS THE FOX VALLY NORTHEAST TOWARD ESCANABA MICHIGAN.
DESPITE FAVORABLE WETBULB ZERO HEIGHTS AROUND 8500 FEET AGL..ONLY
HAVE HAD A COUPLE REPORTS OF SOME PEA SIZE HAIL THUS FAR. WITH PW
VALUES STILL AROUND AN INCH...AND UPPER-LEVEL WINDS CONTINUING TO
WEAKEN AS UPPER TROUGH MOVES OVERHEAD...EXPECT A FEW OF THESE
STORMS TO BE EFFICIENT RAINFALL PRODUCERS PRODUCING SOME BRIEF
HEAVY RAINFALL INTO THE EARLY EVENING. 18Z HRRR AND TO A LESSER
EXTENT THE GFS AND NAM...FOCUS THE BEST LIFT AND ASSOCIATED QPF OVER
THE NORTHEAST PORTION OF THE FORECAST AREA THIS EVENING. THIS SEEMS
REASONABLE GIVEN CURRENT RADAR TRENDS...THUS HAVE ADJUSTED THE QPF
AND POP ACCORDINGLY FOR THIS EVENING. AS UPPER TROUGH SWEEPS
ACROSS THE FORECAST AREA OVERNIGHT...THE ASSOCIATED SURFACE TROUGH
AND SCATTERED SHOWER ACTIVITY WILL ALSO STEADILY PROGRESS
EASTWARD. BASED ON THE LATEST RUN OF THE HRRR...ANTICIPATE THE
SURFACE TROUGH TO MOVE EAST OF THE FOX VALLEY BY AROUND MIDNIGHT.
SOME RESIDUAL LOW-LEVEL MOISTURE IN THE WAKE OF THE SURFACE TROUGH
MAY CONTRIBUTE TO A FEW LINGERING LIGHT SHOWERS OR SPRINKLES OVER
THE LAKE SHORE COUNTIES UNTIL ABOUT 12Z. RESIDUAL LOW LEVEL
MOISTURE REALLY DOES NOT GET SCOURED OUT UNTIL AFTER ABOUT 16Z SO
HAVE SLOWED CLEARING A FEW HOURS ON SUNDAY. BRISK NORTHWEST WINDS
SUNDAY MORNING WILL SLOWLY DIMINISH AS THE DAY PROGRESSES AS
SURFACE HIGH PRESSURE SETTLES IN.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 254 PM CDT SAT JUN 1 2013
HIGH PRESSURE RIDGING SWD FM CANADA WL DOMINATE THE START OF THE
LONG-TERM PERIOD. THAT WL LEAD TO PLENTY OF SUNSHINE AND DRY
CONDITIONS. TEMPS WL FALL WELL BLO NORMAL AT NIGHT. LOOKS LIKE A
PRETTY GOOD CHC OF FROST ACRS THE N SUNDAY NIGHT...AND SOME OF THE
TYPICAL COLD SPOTS COULD EVEN EXPERIENCE A FREEZE. MONDAY NIGHT
MAY NOT BE QUITE AS COLD...BUT AT LEAST PATCHY FROST WL AGAIN BE
POSSIBLE ACRS THE N. WL PROBABLY EVENTUALLY NEED A FROST/FREEZE
HEADLINE FOR THE N FOR SUN NGT...WL HOLD OFF ISSUING THAT NOW AS
LATER FORECASTS HAVE A BETTER CHC OF DISCERNING EXACTLY HOW FAR S
AND E TO TAKE THE HEADLINE.
THE NEXT UPR TROF EMBEDDED IN THE WESTERLIES ACRS THE NRN CONUS
WL BE APPROACHING THE AREA TUE. THE MAJORITY OF THE MODELS DROVE
PCPN WELL E INTO THE FCST AREA DURING THE DAY. BUT IT SEEMS LIKE
DRY AIR WITH THE DEPARTING HIGH PRESSURE SHOULD BE ABLE TO DELAY
THE EWD PROGRESSION OF THE PCPN AT LEAST A LITTLE. SO OPTED TO
KEEP THE MORNING DRY AND THEN LIMIT POPS TO ABOUT THE WRN 1/4 OF
THE FCST AREA DURING THE AFTN.
THE BEST CHC OF PCPN WL COME MID-WK AS THE UPR TROF CROSSES THE
RGN.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 640 PM CDT SAT JUN 1 2013
SURFACE TROF HAS KICKED OFF A LINE OF THUNDERSTORMS OVER EAST
CENTRAL AND FAR NORTHEAST WI...LATE THIS AFTERNOON. THE LINE WAS
MOVING EAST AT 20 MPH AND WILL AFFECT LAKESHORE AIRPORTS THROUGH
01Z. THE STORMS ARE EXPECTED TO WEAKEN SOMEWHAT AS THEY MOVE EAST.
MAIN UPPER TROF TO MOVE THROUGH EASTERN WI THROUGH FIRST HALF OF
NIGHT. AREA OF SCATTERED SHOWERS NOW OVER WESTERN WI TO AFFECT
MAINLY CENTRAL WI THIS EVENING...SOME QUESTION ON WHETHER WILL
HOLD TOGETHER AS IT MOVES FURTHER EAST. LOWER MVFR STRATUS TO
MOVE IN FOR PERIOD BEHIND SHOWERS...EXITING SUN MORNING AS HIGH
PRESSURE MOVES IN.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS.......SKOWRONSKI
SHORT TERM.....ESB
LONG TERM......SKOWRONSKI
AVIATION.......TE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
633 PM CDT SAT JUN 1 2013
.SHORT TERM...(TONIGHT AND SUNDAY TONIGHT)
ISSUED AT 218 PM CDT SAT JUN 1 2013
WATER VAPOR IMAGERY SHOWING THE CLOSED LOW SLOWLY FILLING WITH THE
MAIN CIRCULATION CENTER ROTATING EAST ALONG THE MN/IA BORDER. AT THE
SURFACE...LOW PRESSURE WAS CENTERED OVER SOUTHWEST WI WITH A COLD
FRONT/DRYLINE EXTENDING FROM CENTRAL INTO SOUTHWEST WI. STRONGER
CONVECTION WAS FIRING AHEAD OF THE DRYLINE OVER EASTERN WI IN AN
AXIS OF HIGHER DEWPOINT/INSTABILITY AXIS AND 25-35KT 0-3KM BULK
SHEAR. MEANWHILE...RADAR MOSAIC WAS ALSO SHOWING WEAKER
SHOWER/THUNDERSTORM ACTIVITY ENTERING THE FORECAST AREA FROM MN ON
THE EASTERN PERIPHERY OF STEEPER LOW-MID-LEVEL LAPSE RATES UNDER THE
FILLING CLOSED LOW. RAP ANALYSIS SHOWING THIS AREA IN A ZONE OF VERY
WEAK BULK SHEAR...SO JUST EXPECTING MOSTLY SHOWER ACTIVITY WITH
ISOLATED THUNDER OUT OF THIS ACTIVITY. LOOK FOR THIS CONVECTION TO
CONTINUE MOVING INTO THE AREA THROUGH THE REMAINDER OF THIS
AFTERNOON AND INTO TONIGHT AS THE MID-LEVEL TROUGH AXIS MOVES EAST
ACROSS THE REGION. LOOK FOR THE SHOWERS TO DIMINISH AND SKIES TO
CLEAR FROM WEST TO EAST AFTER MIDNIGHT AS SUBSIDENCE/DRYING TAKES
PLACE BEHIND THE DEPARTING TROUGH.
A RIDGE OF HIGH PRESSURE WILL THEN BUILD INTO THE AREA ON SUNDAY FOR
A DRY/MOSTLY SUNNY DAY. DESPITE MOSTLY SUNNY SKIES...COLD AIR
ADVECTION ON NORTHWEST WINDS OF 10-20 MPH WILL YIELD HIGH
TEMPERATURES SOME 10 DEGREES BELOW NORMAL IN THE LOW/MID 60S.
HIGH PRESSURE WILL BE SITUATED OVERHEAD FOR A CLEAR/COOL/CALM SUNDAY
NIGHT. LOOK FOR LOWS RANGING FROM AROUND 40 DEGREES FOR AREAS
ALONG/NORTHEAST OF I-94...TO THE MID/UPPER 40S ELSEWHERE. GIVEN THE
NEARLY SATURATED GROUND AND THE FACT THE HIGH IS OVERHEAD FOR CALM
WINDS...WAS THINKING SOME FOG WOULD BE POSSIBLE. HOWEVER...BUFKIT
SOUNDINGS SHOWING THAT THERE WILL BE PLENTY OF DRYING DURING THE
DAYTIME SUNDAY AND THEN MAINTAIN AT LEAST A 3-5 DEGREE SPREAD
THROUGH THE OVERNIGHT HOURS. WILL THEREFORE LEAVE FOG MENTION
OUT...BUT MAY BE SOMETHING TO KEEP AN EYE ON.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 218 PM CDT SAT JUN 1 2013
LOOK FOR HIGH PRESSURE TO REMAIN IN CONTROL ACROSS THE AREA THROUGH
MONDAY FOR A CONTINUED DRY BREAK FROM THE SOGGY CONDITIONS OF LATE.
LATEST GFS/ECMWF IN FAIRLY GOOD AGREEMENT IN BRINGING A COUPLE WEAK
MID-LEVEL TROUGHS ACROSS THE NORTHERN PLAINS INTO OUR REGION TUESDAY
THROUGH SATURDAY. VERY LITTLE CAPE/INSTABILITY IS INDICATED BY THE
MODELS WHICH WOULD LEAD TO MAINLY SHOWER CHANCES WITH PERHAPS AN
ISOLATED THUNDERSTORM OR TWO. APPEARS THIS PERIOD WILL ALSO CONTINUE
TO BE MARKED BY COOLER THAN NORMAL TEMPERATURE WITH HIGHS GENERALLY
IN THE 60S TO LOWER 70S AND OVERNIGHT LOWS IN THE 50S.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 633 PM CDT SAT JUN 1 2013
A SECONDARY COLD FRONT WAS CURRENTLY IN THE PROCESS OF MOVING
INTO AND THROUGH THE TAF SITES AS OF 00Z TAF ISSUANCE. THIS FRONT
SHOULD BE COMPLETELY THROUGH BY 02Z...WITH WINDS SWITCHING TO THE
NORTHWEST AND INCREASING TO 15 KT WITH GUSTS UP TO 25 KT. THE GUSTS
SHOULD DIMINISH IN A FEW HOURS THEREAFTER WITH NIGHTTIME COOLING.
A BAND OF SHOWERS HAS BEEN ACCOMPANYING THE FRONTAL PASSAGE...BUT
VISIBILITIES HAVE BEEN MAINLY VFR. THESE LOOK TO LAST MAYBE AN
HOUR OR TWO AT THE TAF SITES. MVFR STRATUS IS FOLLOWING IN THE
WAKE OF THE COLD FRONT...WHICH EXTENDS BACK INTO CENTRAL
MINNESOTA. EXPECT THE MVFR STRATUS TO MOVE INTO THE TAF SITES FOR
TONIGHT...WITH CONDITIONS IMPROVING TO VFR BY LATE SUNDAY MORNING
AS DAYTIME MIXING AND DRIER AIR FROM CANADA HELP SCATTER OUT THE
CLOUDS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1248 PM CDT FRI MAY 31 2013
.UPDATE...
ISSUED AT 1114 AM CDT FRI MAY 31 2013
THE MAIN FOCUS THROUGH TONIGHT IS ON THE CONVECTIVE POTENTIAL
ACROSS THE REGION. CURRENT SURFACE ANALYSIS SHOWS AN UNCAPPED
ENVIRONMENT JUST OUT AHEAD OF A DRY LINE THAT RUNS FROM JUST EAST
OF THE TWIN CITIES ALONG THE INTERSTATE 35 CORRIDOR THROUGH
MINNESOTA AND IOWA. MODIFIED 31.14Z RAP SOUNDINGS SHOW AN UNCAPPED
FAT CAPE PROFILE BY EARLY AFTERNOON WITH OVER 2000 J/KG OF SURFACE
BASED CAPE DEVELOPING. DEEP SHEAR LOOKS FAVORABLE WITH THE 31.14Z
RAP SHOWING A 50-65KT 500MB JET STREAK EXTENDING FROM THE SOUTHERN
PLAINS NORTHEAST THROUGH THE UPPER MISSISSIPPI RIVER VALLEY
REGION. WITH THIS MID LEVEL JET STREAK NOT SHIFTING EAST MUCH
THROUGH TONIGHT...0-6KM SHEAR REMAINS HIGH AT AROUND 60KTS THROUGH
THIS AFTERNOON AND EVENING. DIRECTIONALLY...THE SHEAR IS MAINLY
UNIDIRECTIONAL OUT OF THE SOUTHWEST FROM THE LOW LEVELS UP...BUT
THERE IS ENOUGH OF A SOUTHERLY COMPONENT TO THE SURFACE WINDS THAT
0-1KM SHEAR STAYS UP AS WELL. GIVEN ALL THIS...THE CURRENT
EXPECTATION WITH STORM MODE IS THAT WITH THE HIGH CAPE/SHEAR
ENVIRONMENT IS THAT STORMS WILL RAPIDLY DEVELOP AHEAD OF THE DRY
LINE THROUGH THIS AFTERNOON WITH LARGE HAIL BEING THE MAIN THREAT
TO START WITH A FEW SUPERCELLS POSSIBLE. CAN NOT RULE OUT A
TORNADO DEVELOPING DURING THIS PHASE AS WELL...PARTICULARLY WHERE
SURFACE WINDS STAY MORE OUT OF THE SOUTH-SOUTHEAST. WITH
TIME...THE ISOLATED/SCATTERED CELLS SHOULD CONVERGE INTO A SQUALL
LINE THIS EVENING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 329 AM CDT FRI MAY 31 2013
TWO AREAS OF CONVECTION THIS MORNING THAT MAY IMPACT THE AREA. THE
FIRST IS PRIMARILY ALREADY OFF THE NORTHWEST OF THE AREA FROM
NORTHWEST MINNESOTA INTO WESTERN WISCONSIN. THIS AREA IS MOVING
OFF TO THE NORTH/NORTHEAST AND IS NOT EXPECTED TO IMPACT THE
FORECAST AREA. THE OTHER AREA OF CONVECTION IS OVER NORTHWEST
MISSOURI AND IS MOVING TO THE NORTHEAST. THE HRRR SEEMS TO BE
HANDLING THIS THE BEST...BUT IS CONSIDERABLY TOO SLOW WITH IT. THE
TREND FROM THE 31.04Z AND 31.05Z RUNS IS FOR THIS AREA TO MOVE
NORTHEAST ACROSS EASTERN IOWA INTO NORTHERN ILLINOIS AND FOR THE
MOST PART MISSING THE AREA TO THE SOUTH. THE 31.00Z ECMWF ALSO
SHOWS THIS AREA COMING OUT OF MISSOURI BUT TAKES IT FARTHER TO THE
NORTHWEST IMPACTING THE SOUTHERN AND EASTERN AREAS FROM LATE
MORNING THROUGH THE AFTERNOON. THE PREVIOUS FORECAST WAS TRENDED
TOWARD THE POSSIBILITY OF THIS CONVECTION COMING INTO THE AREA SO
HAVE MAINTAINED THESE TRENDS BUT LIMITED THE HIGHER RAIN CHANCES
TO THE SOUTHEAST SECTIONS OF THE FORECAST AREA. BY LATE IN THE
AFTERNOON AND INTO THE EVENING...ALL THE MODELS ARE SHOWING WHAT
LOOKS LIKE A DRY LINE/WIND SHIFT DEVELOPING AHEAD OF THE SURFACE
LOW AND MOVING EAST TOWARD THE AREA. THERE SHOULD BE ANOTHER SHORT
WAVE TROUGH ROUNDING THE UPPER LEVEL LOW TO PROVIDE DYNAMIC LIFT
OVER THIS DRY LINE/WIND SHIFT. BOTH THE 31.00Z NAM AND GFS SHOW A
JET CORE ALSO COMING AROUND THE UPPER LEVEL LOW WITH THE LEFT EXIT
REGION COMING OVER THE AREA TO ADD SOME AGEOSTROPHIC MOTIONS TO THE
FORCING FROM THE SHORT WAVE TROUGH. THIS SHOULD BE ENOUGH FORCING
TO CAUSE A LINE OF CONVECTION TO DEVELOP ALONG THIS DRY LINE AND
THEN WORK RAPIDLY EAST ACROSS THE AREA DURING THE EVENING. SOME
POTENTIAL FOR SEVERE TODAY...BUT THIS IS DEFINITELY NOT AS HIGH AS
THE PAST COUPLE OF DAYS. ML CAPES OF 1000 TO POSSIBLY AS MUCH AS
2000 J/KG SHOULD DEVELOP TODAY AHEAD OF THE DRY LINE. THE BEST
0-6KM SHEAR WILL BE WELL OUT AHEAD OF THE DRY LINE AND WILL LINE
UP BETTER WITH THE EXPECTED CONVECTION TO COME NORTHEAST OUT OF
MISSOURI. HOWEVER...THE 0-3 KM SHEAR SHOULD BE AROUND 30 KNOTS
AHEAD OF THE DRY LINE SO THE POTENTIAL FOR STORMS THIS AFTERNOON
AND EVENING TO PRODUCE DAMAGING WINDS AND HAIL. ALL THE ACTIVITY
SHOULD QUICKLY DIE DOWN AFTER MIDNIGHT AS IT MOVES OFF TO THE EAST
OF THE AREA. BOTH THE NAM AND GFS SHOW THE PRECIPITABLE WATERS
LOWERING DURING THE DAY AS DRIER AIR WRAPS IN FROM THE WEST. WHILE
ANY THUNDERSTORMS MAY PRODUCE SOME LOCALLY HEAVY RAIN...FEEL THAT
THE POTENTIAL FOR WIDESPREAD HEAVY RAINS TO PRODUCE FLASH FLOODING
IS NOT THERE TO SUPPORT THE NEED FOR ANOTHER FLASH FLOOD WATCH.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 329 AM CDT FRI MAY 31 2013
AT LONG LAST...THIS STUBBORN SYSTEM WILL BEGIN TO MAKE A MOVE TO
THE EAST SATURDAY. AS IT DOES...THE SURFACE LOW WILL MOVE FROM
CENTRAL MINNESOTA INTO NORTHERN WISCONSIN AS THE UPPER LEVEL LOW
BECOMES AN OPEN WAVE. THE LAST SHORT WAVE TROUGH WITH THIS SYSTEM
IS EXPECTED TO BE MOVING ACROSS THE AREA AND BE PRODUCING AROUND 8
PVU/S OF VORTICITY ADVECTION IN THE 500-300 MB LAYER. THIS FORCING
FROM THE WAVE COMBINED WITH BEING IN THE DEFORMATION AREA OF THE
SURFACE LOW SHOULD BE ENOUGH TO GENERATE SHOWERS ACROSS MUCH OF
THE AREA. MU CAPES SHOULD BE AROUND 200-300 J/KG IN THE AFTERNOON
WHICH WILL BE GOOD ENOUGH TO PRODUCE SOME ISOLATED THUNDER. THE
REMAINING SHOWERS SHOULD THEN MOVE OFF TO THE EAST SATURDAY NIGHT
WITH SUNDAY BEING THE FIRST DAY IN ABOUT A WEEK WITH NO CHANCE OF
RAIN. MONDAY ALSO LOOKS TO BE DRY WITH HIGH PRESSURE OVER THE AREA
BUT THEN THE RAIN CHANCES START TO RETURN FOR MONDAY NIGHT. THE
31.00Z GFS...GEM AND ECMWF ALL SHOW ANOTHER CLOSED LOW MOVING
TOWARD THE AREA FROM THE PACIFIC NORTHWEST. PLENTY OF DIFFERENCES
THOUGH ON HOW FAST THIS SYSTEM WILL START TO IMPACT THE AREA. THE
OPERATIONAL GFS IS THE FASTEST BRINGING THIS SYSTEM IN...EVEN
FASTER THAN ITS ENSEMBLE MEAN WHILE THE ECMWF IS THE SLOWEST. THIS
LOOKS TO BE ANOTHER SLOW MOVING SYSTEM KEEPING RAIN CHANCES IN THE
FORECAST FOR THE REMAINDER OF THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1248 PM CDT FRI MAY 31 2013
THE MAIN FOCUS AT THE TAF SITES IS WITH THE TIMING ON WHEN ANY
SHOWERS OR THUNDERSTORMS WILL GET INTO THE TAF SITES. SHOWERS HAVE
ALREADY DEVELOPED NEAR RST AND WILL DRIFT TO THE EAST THROUGH THE
AFTERNOON. WITH AN UNSTABLE ENVIRONMENT IN PLACE...THESE SHOWERS
WILL QUICKLY STRENGTHEN EARLY THIS AFTERNOON WITH THUNDERSTORMS
LIKELY AT RST BETWEEN 19Z/23Z. AS THE STORMS MARCH EAST...THEY
SHOULD REACH LSE SOMETIME BETWEEN 23Z AND 02Z. MVFR CUMULUS FIELD
WILL LIKELY STAY IN PLACE OR GRADUALLY CLIMB THIS AFTERNOON BEFORE
MVFR/IFR CONDITIONS COME IN WITH THE THUNDERSTORMS. CONDITIONS
SHOULD CLEAR OUT LATER THIS EVENING WITH WINDS SUBSIDING
OVERNIGHT.
&&
.HYDROLOGY...
ISSUED AT 329 AM CDT FRI MAY 31 2013
TURKEY RIVER...
WITH THURSDAY BEING MUCH DRIER THAN EXPECTED IN NORTHEAST IOWA...THE
TURKEY RIVER IS COMING IN MUCH LOWER THAN ORIGINALLY ANTICIPATED.
ELKADER IS EXPECTED TO CREST AROUND 16.5 FEET. THIS IS ABOUT 2 FEET
LOWER THAN THE PREVIOUS FORECAST. THIS IN TURN WILL RESULT IN A MUCH
LOWER CREST FOR GARBER. THE RIVER HAS ALREADY CRESTED AROUND
22.1 FEET. IT SHOULD REMAIN AROUND THIS LEVEL THROUGH MUCH OF TODAY
AND THEN BEGIN A SLOW FALL.
UPPER IOWA...
DORCHESTER HAS FLATTENED OUT AROUND 13.4 FEET. WITH DECORAH
CONTINUING TO RISE UPSTREAM...EXPECT THAT DORCHESTER WILL ONCE AGAIN
START TO RISE THIS MORNING. CONSIDERING THE RAINFALL ACROSS THIS
BASIN ON THURSDAY STILL NOT QUITE SURE WHETHER THE CREST LATER THIS
AFTERNOON WILL BE ABOUT A HALF FEET /15.5 FEET/ HIGHER THAN ITS
PREVIOUS CREST OF 15 FEET ON THURSDAY MORNING. AM MORE INCLINED THAT
IT WILL COME IN WITH A SIMILAR AS THURSDAY MORNING.
KICKAPOO RIVER...
THE UPPER REACHES OF THE KICKAPOO HAVE ALREADY CRESTED AND STARTED
TO FALL RAPIDLY...THEREFORE...LA FARGE WILL BE ADJUSTED TO CREST
LOWER THAN EXPECTED /STILL BELOW FLOOD STAGE/
BLACK RIVER...
BLACK RIVER FALLS IS CONTINUING TO RISE RATHER RAPIDLY THIS MORNING.
LOOKING AT THE WATER UPSTREAM...THE NORTH CENTRAL RIVER FORECAST
CENTER IS EXPECTING IT TO NOW CREST AROUND 49.3 FEET LATER TODAY.
TREMPEALEAU RIVER...
DUE TO THE BROADER EXPANSE NEAR DODGE...EXPECT TO SEE A SLOW AND
STEADY RISE INTO THE WEEKEND. IT STILL LOOKS LIKE IT WILL CREST ON
SUNDAY AROUND 9.6 FEET.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...HALBACH
SHORT TERM...04
LONG TERM...04
AVIATION...HALBACH
HYDROLOGY...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1114 AM CDT FRI MAY 31 2013
.UPDATE...
ISSUED AT 1114 AM CDT FRI MAY 31 2013
THE MAIN FOCUS THROUGH TONIGHT IS ON THE CONVECTIVE POTENTIAL
ACROSS THE REGION. CURRENT SURFACE ANALYSIS SHOWS AN UNCAPPED
ENVIRONMENT JUST OUT AHEAD OF A DRY LINE THAT RUNS FROM JUST EAST
OF THE TWIN CITIES ALONG THE INTERSTATE 35 CORRIDOR THROUGH
MINNESOTA AND IOWA. MODIFIED 31.14Z RAP SOUNDINGS SHOW AN UNCAPPED
FAT CAPE PROFILE BY EARLY AFTERNOON WITH OVER 2000 J/KG OF SURFACE
BASED CAPE DEVELOPING. DEEP SHEAR LOOKS FAVORABLE WITH THE 31.14Z
RAP SHOWING A 50-65KT 500MB JET STREAK EXTENDING FROM THE SOUTHERN
PLAINS NORTHEAST THROUGH THE UPPER MISSISSIPPI RIVER VALLEY
REGION. WITH THIS MID LEVEL JET STREAK NOT SHIFTING EAST MUCH
THROUGH TONIGHT...0-6KM SHEAR REMAINS HIGH AT AROUND 60KTS THROUGH
THIS AFTERNOON AND EVENING. DIRECTIONALLY...THE SHEAR IS MAINLY
UNIDIRECTIONAL OUT OF THE SOUTHWEST FROM THE LOW LEVELS UP...BUT
THERE IS ENOUGH OF A SOUTHERLY COMPONENT TO THE SURFACE WINDS THAT
0-1KM SHEAR STAYS UP AS WELL. GIVEN ALL THIS...THE CURRENT
EXPECTATION WITH STORM MODE IS THAT WITH THE HIGH CAPE/SHEAR
ENVIRONMENT IS THAT STORMS WILL RAPIDLY DEVELOP AHEAD OF THE DRY
LINE THROUGH THIS AFTERNOON WITH LARGE HAIL BEING THE MAIN THREAT
TO START WITH A FEW SUPERCELLS POSSIBLE. CAN NOT RULE OUT A
TORNADO DEVELOPING DURING THIS PHASE AS WELL...PARTICULARLY WHERE
SURFACE WINDS STAY MORE OUT OF THE SOUTH-SOUTHEAST. WITH
TIME...THE ISOLATED/SCATTERED CELLS SHOULD CONVERGE INTO A SQUALL
LINE THIS EVENING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 329 AM CDT FRI MAY 31 2013
TWO AREAS OF CONVECTION THIS MORNING THAT MAY IMPACT THE AREA. THE
FIRST IS PRIMARILY ALREADY OFF THE NORTHWEST OF THE AREA FROM
NORTHWEST MINNESOTA INTO WESTERN WISCONSIN. THIS AREA IS MOVING
OFF TO THE NORTH/NORTHEAST AND IS NOT EXPECTED TO IMPACT THE
FORECAST AREA. THE OTHER AREA OF CONVECTION IS OVER NORTHWEST
MISSOURI AND IS MOVING TO THE NORTHEAST. THE HRRR SEEMS TO BE
HANDLING THIS THE BEST...BUT IS CONSIDERABLY TOO SLOW WITH IT. THE
TREND FROM THE 31.04Z AND 31.05Z RUNS IS FOR THIS AREA TO MOVE
NORTHEAST ACROSS EASTERN IOWA INTO NORTHERN ILLINOIS AND FOR THE
MOST PART MISSING THE AREA TO THE SOUTH. THE 31.00Z ECMWF ALSO
SHOWS THIS AREA COMING OUT OF MISSOURI BUT TAKES IT FARTHER TO THE
NORTHWEST IMPACTING THE SOUTHERN AND EASTERN AREAS FROM LATE
MORNING THROUGH THE AFTERNOON. THE PREVIOUS FORECAST WAS TRENDED
TOWARD THE POSSIBILITY OF THIS CONVECTION COMING INTO THE AREA SO
HAVE MAINTAINED THESE TRENDS BUT LIMITED THE HIGHER RAIN CHANCES
TO THE SOUTHEAST SECTIONS OF THE FORECAST AREA. BY LATE IN THE
AFTERNOON AND INTO THE EVENING...ALL THE MODELS ARE SHOWING WHAT
LOOKS LIKE A DRY LINE/WIND SHIFT DEVELOPING AHEAD OF THE SURFACE
LOW AND MOVING EAST TOWARD THE AREA. THERE SHOULD BE ANOTHER SHORT
WAVE TROUGH ROUNDING THE UPPER LEVEL LOW TO PROVIDE DYNAMIC LIFT
OVER THIS DRY LINE/WIND SHIFT. BOTH THE 31.00Z NAM AND GFS SHOW A
JET CORE ALSO COMING AROUND THE UPPER LEVEL LOW WITH THE LEFT EXIT
REGION COMING OVER THE AREA TO ADD SOME AGEOSTROPHIC MOTIONS TO THE
FORCING FROM THE SHORT WAVE TROUGH. THIS SHOULD BE ENOUGH FORCING
TO CAUSE A LINE OF CONVECTION TO DEVELOP ALONG THIS DRY LINE AND
THEN WORK RAPIDLY EAST ACROSS THE AREA DURING THE EVENING. SOME
POTENTIAL FOR SEVERE TODAY...BUT THIS IS DEFINITELY NOT AS HIGH AS
THE PAST COUPLE OF DAYS. ML CAPES OF 1000 TO POSSIBLY AS MUCH AS
2000 J/KG SHOULD DEVELOP TODAY AHEAD OF THE DRY LINE. THE BEST
0-6KM SHEAR WILL BE WELL OUT AHEAD OF THE DRY LINE AND WILL LINE
UP BETTER WITH THE EXPECTED CONVECTION TO COME NORTHEAST OUT OF
MISSOURI. HOWEVER...THE 0-3 KM SHEAR SHOULD BE AROUND 30 KNOTS
AHEAD OF THE DRY LINE SO THE POTENTIAL FOR STORMS THIS AFTERNOON
AND EVENING TO PRODUCE DAMAGING WINDS AND HAIL. ALL THE ACTIVITY
SHOULD QUICKLY DIE DOWN AFTER MIDNIGHT AS IT MOVES OFF TO THE EAST
OF THE AREA. BOTH THE NAM AND GFS SHOW THE PRECIPITABLE WATERS
LOWERING DURING THE DAY AS DRIER AIR WRAPS IN FROM THE WEST. WHILE
ANY THUNDERSTORMS MAY PRODUCE SOME LOCALLY HEAVY RAIN...FEEL THAT
THE POTENTIAL FOR WIDESPREAD HEAVY RAINS TO PRODUCE FLASH FLOODING
IS NOT THERE TO SUPPORT THE NEED FOR ANOTHER FLASH FLOOD WATCH.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 329 AM CDT FRI MAY 31 2013
AT LONG LAST...THIS STUBBORN SYSTEM WILL BEGIN TO MAKE A MOVE TO
THE EAST SATURDAY. AS IT DOES...THE SURFACE LOW WILL MOVE FROM
CENTRAL MINNESOTA INTO NORTHERN WISCONSIN AS THE UPPER LEVEL LOW
BECOMES AN OPEN WAVE. THE LAST SHORT WAVE TROUGH WITH THIS SYSTEM
IS EXPECTED TO BE MOVING ACROSS THE AREA AND BE PRODUCING AROUND 8
PVU/S OF VORTICITY ADVECTION IN THE 500-300 MB LAYER. THIS FORCING
FROM THE WAVE COMBINED WITH BEING IN THE DEFORMATION AREA OF THE
SURFACE LOW SHOULD BE ENOUGH TO GENERATE SHOWERS ACROSS MUCH OF
THE AREA. MU CAPES SHOULD BE AROUND 200-300 J/KG IN THE AFTERNOON
WHICH WILL BE GOOD ENOUGH TO PRODUCE SOME ISOLATED THUNDER. THE
REMAINING SHOWERS SHOULD THEN MOVE OFF TO THE EAST SATURDAY NIGHT
WITH SUNDAY BEING THE FIRST DAY IN ABOUT A WEEK WITH NO CHANCE OF
RAIN. MONDAY ALSO LOOKS TO BE DRY WITH HIGH PRESSURE OVER THE AREA
BUT THEN THE RAIN CHANCES START TO RETURN FOR MONDAY NIGHT. THE
31.00Z GFS...GEM AND ECMWF ALL SHOW ANOTHER CLOSED LOW MOVING
TOWARD THE AREA FROM THE PACIFIC NORTHWEST. PLENTY OF DIFFERENCES
THOUGH ON HOW FAST THIS SYSTEM WILL START TO IMPACT THE AREA. THE
OPERATIONAL GFS IS THE FASTEST BRINGING THIS SYSTEM IN...EVEN
FASTER THAN ITS ENSEMBLE MEAN WHILE THE ECMWF IS THE SLOWEST. THIS
LOOKS TO BE ANOTHER SLOW MOVING SYSTEM KEEPING RAIN CHANCES IN THE
FORECAST FOR THE REMAINDER OF THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 700 AM CDT FRI MAY 31 2013
IFR TO MVFR CEILINGS WILL GRADUALLY BECOME VFR BY 31.15Z. SHOWERS
AND THUNDERSTORMS WILL DEVELOP AHEAD OF A COLD FRONT LATE THIS
AFTERNOON AND EVENING. THESE THUNDERSTORMS WILL AFFECT KRST
BETWEEN 31.22Z AND 01.04Z...AND KLSE BETWEEN 01.00Z AND 01.06Z. A
FEW OF THESE THUNDERSTORMS MAY BECOME SEVERE. THE MAIN THREATS
WILL BE LARGE HAIL AND DAMAGING WINDS. THERE MAY BE EVEN AN
ISOLATED TORNADO. ONCE THE FRONT CLEARS THE AREA CEILINGS WILL
CLIMB TO AROUND 10K FEET.
&&
.HYDROLOGY...
ISSUED AT 329 AM CDT FRI MAY 31 2013
TURKEY RIVER...
WITH THURSDAY BEING MUCH DRIER THAN EXPECTED IN NORTHEAST IOWA...THE
TURKEY RIVER IS COMING IN MUCH LOWER THAN ORIGINALLY ANTICIPATED.
ELKADER IS EXPECTED TO CREST AROUND 16.5 FEET. THIS IS ABOUT 2 FEET
LOWER THAN THE PREVIOUS FORECAST. THIS IN TURN WILL RESULT IN A MUCH
LOWER CREST FOR GARBER. THE RIVER HAS ALREADY CRESTED AROUND
22.1 FEET. IT SHOULD REMAIN AROUND THIS LEVEL THROUGH MUCH OF TODAY
AND THEN BEGIN A SLOW FALL.
UPPER IOWA...
DORCHESTER HAS FLATTENED OUT AROUND 13.4 FEET. WITH DECORAH
CONTINUING TO RISE UPSTREAM...EXPECT THAT DORCHESTER WILL ONCE AGAIN
START TO RISE THIS MORNING. CONSIDERING THE RAINFALL ACROSS THIS
BASIN ON THURSDAY STILL NOT QUITE SURE WHETHER THE CREST LATER THIS
AFTERNOON WILL BE ABOUT A HALF FEET /15.5 FEET/ HIGHER THAN ITS
PREVIOUS CREST OF 15 FEET ON THURSDAY MORNING. AM MORE INCLINED THAT
IT WILL COME IN WITH A SIMILAR AS THURSDAY MORNING.
KICKAPOO RIVER...
THE UPPER REACHES OF THE KICKAPOO HAVE ALREADY CRESTED AND STARTED
TO FALL RAPIDLY...THEREFORE...LA FARGE WILL BE ADJUSTED TO CREST
LOWER THAN EXPECTED /STILL BELOW FLOOD STAGE/
BLACK RIVER...
BLACK RIVER FALLS IS CONTINUING TO RISE RATHER RAPIDLY THIS MORNING.
LOOKING AT THE WATER UPSTREAM...THE NORTH CENTRAL RIVER FORECAST
CENTER IS EXPECTING IT TO NOW CREST AROUND 49.3 FEET LATER TODAY.
TREMPEALEAU RIVER...
DUE TO THE BROADER EXPANSE NEAR DODGE...EXPECT TO SEE A SLOW AND
STEADY RISE INTO THE WEEKEND. IT STILL LOOKS LIKE IT WILL CREST ON
SUNDAY AROUND 9.6 FEET.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...HALBACH
SHORT TERM...04
LONG TERM...04
AVIATION...BOYNE
HYDROLOGY...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
703 AM CDT FRI MAY 31 2013
.UPDATE...THIS MORNING
ISSUED AT 700 AM CDT FRI MAY 31 2013
EARLY THIS MORNING...SHOWERS WILL CONTINUE TO BE FOUND IN WISCONSIN
NORTH OF THE INTERSTATE 90 CORRIDOR. THESE SHOWERS ARE DEVELOPING
ON NOSE OF THE DRY SLOT...AND SHOULD BE NORTHEAST OF THE AREA BY
31.15Z.
FOR MID TO LATE MORNING...THE MAIN CONCERN IS WHERE THE MESOSCALE
CONVECTIVE COMPLEX OVER MISSOURI WILL TRACK THIS MORNING. THE
LATEST RAP CONTINUES TO BRING THIS SYSTEM NORTHEAST INTO THE AREA.
MEANWHILE THE HRRR SHOWS THAT THIS SYSTEM WILL REMAIN SOUTH OF THE
AREA. LOOKING AT THE MEAN WIND VECTORS OFF OF THE RADAR...THE HRRR
MAKES MUCH MORE SENSE...SO TRENDED THE FORECAST THAT WAY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 329 AM CDT FRI MAY 31 2013
TWO AREAS OF CONVECTION THIS MORNING THAT MAY IMPACT THE AREA. THE
FIRST IS PRIMARILY ALREADY OFF THE NORTHWEST OF THE AREA FROM
NORTHWEST MINNESOTA INTO WESTERN WISCONSIN. THIS AREA IS MOVING
OFF TO THE NORTH/NORTHEAST AND IS NOT EXPECTED TO IMPACT THE
FORECAST AREA. THE OTHER AREA OF CONVECTION IS OVER NORTHWEST
MISSOURI AND IS MOVING TO THE NORTHEAST. THE HRRR SEEMS TO BE
HANDLING THIS THE BEST...BUT IS CONSIDERABLY TOO SLOW WITH IT. THE
TREND FROM THE 31.04Z AND 31.05Z RUNS IS FOR THIS AREA TO MOVE
NORTHEAST ACROSS EASTERN IOWA INTO NORTHERN ILLINOIS AND FOR THE
MOST PART MISSING THE AREA TO THE SOUTH. THE 31.00Z ECMWF ALSO
SHOWS THIS AREA COMING OUT OF MISSOURI BUT TAKES IT FARTHER TO THE
NORTHWEST IMPACTING THE SOUTHERN AND EASTERN AREAS FROM LATE
MORNING THROUGH THE AFTERNOON. THE PREVIOUS FORECAST WAS TRENDED
TOWARD THE POSSIBILITY OF THIS CONVECTION COMING INTO THE AREA SO
HAVE MAINTAINED THESE TRENDS BUT LIMITED THE HIGHER RAIN CHANCES
TO THE SOUTHEAST SECTIONS OF THE FORECAST AREA. BY LATE IN THE
AFTERNOON AND INTO THE EVENING...ALL THE MODELS ARE SHOWING WHAT
LOOKS LIKE A DRY LINE/WIND SHIFT DEVELOPING AHEAD OF THE SURFACE
LOW AND MOVING EAST TOWARD THE AREA. THERE SHOULD BE ANOTHER SHORT
WAVE TROUGH ROUNDING THE UPPER LEVEL LOW TO PROVIDE DYNAMIC LIFT
OVER THIS DRY LINE/WIND SHIFT. BOTH THE 31.00Z NAM AND GFS SHOW A
JET CORE ALSO COMING AROUND THE UPPER LEVEL LOW WITH THE LEFT EXIT
REGION COMING OVER THE AREA TO ADD SOME AGEOSTROPHIC MOTIONS TO THE
FORCING FROM THE SHORT WAVE TROUGH. THIS SHOULD BE ENOUGH FORCING
TO CAUSE A LINE OF CONVECTION TO DEVELOP ALONG THIS DRY LINE AND
THEN WORK RAPIDLY EAST ACROSS THE AREA DURING THE EVENING. SOME
POTENTIAL FOR SEVERE TODAY...BUT THIS IS DEFINITELY NOT AS HIGH AS
THE PAST COUPLE OF DAYS. ML CAPES OF 1000 TO POSSIBLY AS MUCH AS
2000 J/KG SHOULD DEVELOP TODAY AHEAD OF THE DRY LINE. THE BEST
0-6KM SHEAR WILL BE WELL OUT AHEAD OF THE DRY LINE AND WILL LINE
UP BETTER WITH THE EXPECTED CONVECTION TO COME NORTHEAST OUT OF
MISSOURI. HOWEVER...THE 0-3 KM SHEAR SHOULD BE AROUND 30 KNOTS
AHEAD OF THE DRY LINE SO THE POTENTIAL FOR STORMS THIS AFTERNOON
AND EVENING TO PRODUCE DAMAGING WINDS AND HAIL. ALL THE ACTIVITY
SHOULD QUICKLY DIE DOWN AFTER MIDNIGHT AS IT MOVES OFF TO THE EAST
OF THE AREA. BOTH THE NAM AND GFS SHOW THE PRECIPITABLE WATERS
LOWERING DURING THE DAY AS DRIER AIR WRAPS IN FROM THE WEST. WHILE
ANY THUNDERSTORMS MAY PRODUCE SOME LOCALLY HEAVY RAIN...FEEL THAT
THE POTENTIAL FOR WIDESPREAD HEAVY RAINS TO PRODUCE FLASH FLOODING
IS NOT THERE TO SUPPORT THE NEED FOR ANOTHER FLASH FLOOD WATCH.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 329 AM CDT FRI MAY 31 2013
AT LONG LAST...THIS STUBBORN SYSTEM WILL BEGIN TO MAKE A MOVE TO
THE EAST SATURDAY. AS IT DOES...THE SURFACE LOW WILL MOVE FROM
CENTRAL MINNESOTA INTO NORTHERN WISCONSIN AS THE UPPER LEVEL LOW
BECOMES AN OPEN WAVE. THE LAST SHORT WAVE TROUGH WITH THIS SYSTEM
IS EXPECTED TO BE MOVING ACROSS THE AREA AND BE PRODUCING AROUND 8
PVU/S OF VORTICITY ADVECTION IN THE 500-300 MB LAYER. THIS FORCING
FROM THE WAVE COMBINED WITH BEING IN THE DEFORMATION AREA OF THE
SURFACE LOW SHOULD BE ENOUGH TO GENERATE SHOWERS ACROSS MUCH OF
THE AREA. MU CAPES SHOULD BE AROUND 200-300 J/KG IN THE AFTERNOON
WHICH WILL BE GOOD ENOUGH TO PRODUCE SOME ISOLATED THUNDER. THE
REMAINING SHOWERS SHOULD THEN MOVE OFF TO THE EAST SATURDAY NIGHT
WITH SUNDAY BEING THE FIRST DAY IN ABOUT A WEEK WITH NO CHANCE OF
RAIN. MONDAY ALSO LOOKS TO BE DRY WITH HIGH PRESSURE OVER THE AREA
BUT THEN THE RAIN CHANCES START TO RETURN FOR MONDAY NIGHT. THE
31.00Z GFS...GEM AND ECMWF ALL SHOW ANOTHER CLOSED LOW MOVING
TOWARD THE AREA FROM THE PACIFIC NORTHWEST. PLENTY OF DIFFERENCES
THOUGH ON HOW FAST THIS SYSTEM WILL START TO IMPACT THE AREA. THE
OPERATIONAL GFS IS THE FASTEST BRINGING THIS SYSTEM IN...EVEN
FASTER THAN ITS ENSEMBLE MEAN WHILE THE ECMWF IS THE SLOWEST. THIS
LOOKS TO BE ANOTHER SLOW MOVING SYSTEM KEEPING RAIN CHANCES IN THE
FORECAST FOR THE REMAINDER OF THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 700 AM CDT FRI MAY 31 2013
IFR TO MVFR CEILINGS WILL GRADUALLY BECOME VFR BY 31.15Z. SHOWERS
AND THUNDERSTORMS WILL DEVELOP AHEAD OF A COLD FRONT LATE THIS
AFTERNOON AND EVENING. THESE THUNDERSTORMS WILL AFFECT KRST
BETWEEN 31.22Z AND 01.04Z...AND KLSE BETWEEN 01.00Z AND 01.06Z. A
FEW OF THESE THUNDERSTORMS MAY BECOME SEVERE. THE MAIN THREATS
WILL BE LARGE HAIL AND DAMAGING WINDS. THERE MAY BE EVEN AN
ISOLATED TORNADO. ONCE THE FRONT CLEARS THE AREA CEILINGS WILL
CLIMB TO AROUND 10K FEET.
&&
.HYDROLOGY...
ISSUED AT 329 AM CDT FRI MAY 31 2013
TURKEY RIVER...
WITH THURSDAY BEING MUCH DRIER THAN EXPECTED IN NORTHEAST IOWA...THE
TURKEY RIVER IS COMING IN MUCH LOWER THAN ORIGINALLY ANTICIPATED.
ELKADER IS EXPECTED TO CREST AROUND 16.5 FEET. THIS IS ABOUT 2 FEET
LOWER THAN THE PREVIOUS FORECAST. THIS IN TURN WILL RESULT IN A MUCH
LOWER CREST FOR GARBER. THE RIVER HAS ALREADY CRESTED AROUND
22.1 FEET. IT SHOULD REMAIN AROUND THIS LEVEL THROUGH MUCH OF TODAY
AND THEN BEGIN A SLOW FALL.
UPPER IOWA...
DORCHESTER HAS FLATTENED OUT AROUND 13.4 FEET. WITH DECORAH
CONTINUING TO RISE UPSTREAM...EXPECT THAT DORCHESTER WILL ONCE AGAIN
START TO RISE THIS MORNING. CONSIDERING THE RAINFALL ACROSS THIS
BASIN ON THURSDAY STILL NOT QUITE SURE WHETHER THE CREST LATER THIS
AFTERNOON WILL BE ABOUT A HALF FEET /15.5 FEET/ HIGHER THAN ITS
PREVIOUS CREST OF 15 FEET ON THURSDAY MORNING. AM MORE INCLINED THAT
IT WILL COME IN WITH A SIMILAR AS THURSDAY MORNING.
KICKAPOO RIVER...
THE UPPER REACHES OF THE KICKAPOO HAVE ALREADY CRESTED AND STARTED
TO FALL RAPIDLY...THEREFORE...LA FARGE WILL BE ADJUSTED TO CREST
LOWER THAN EXPECTED /STILL BELOW FLOOD STAGE/
BLACK RIVER...
BLACK RIVER FALLS IS CONTINUING TO RISE RATHER RAPIDLY THIS MORNING.
LOOKING AT THE WATER UPSTREAM...THE NORTH CENTRAL RIVER FORECAST
CENTER IS EXPECTING IT TO NOW CREST AROUND 49.3 FEET LATER TODAY.
TREMPEALEAU RIVER...
DUE TO THE BROADER EXPANSE NEAR DODGE...EXPECT TO SEE A SLOW AND
STEADY RISE INTO THE WEEKEND. IT STILL LOOKS LIKE IT WILL CREST ON
SUNDAY AROUND 9.6 FEET.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...BOYNE
SHORT TERM...04
LONG TERM...04
AVIATION...BOYNE
HYDROLOGY...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
329 AM CDT FRI MAY 31 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 329 AM CDT FRI MAY 31 2013
TWO AREAS OF CONVECTION THIS MORNING THAT MAY IMPACT THE AREA. THE
FIRST IS PRIMARILY ALREADY OFF THE NORTHWEST OF THE AREA FROM
NORTHWEST MINNESOTA INTO WESTERN WISCONSIN. THIS AREA IS MOVING
OFF TO THE NORTH/NORTHEAST AND IS NOT EXPECTED TO IMPACT THE
FORECAST AREA. THE OTHER AREA OF CONVECTION IS OVER NORTHWEST
MISSOURI AND IS MOVING TO THE NORTHEAST. THE HRRR SEEMS TO BE
HANDLING THIS THE BEST...BUT IS CONSIDERABLY TOO SLOW WITH IT. THE
TREND FROM THE 31.04Z AND 31.05Z RUNS IS FOR THIS AREA TO MOVE
NORTHEAST ACROSS EASTERN IOWA INTO NORTHERN ILLINOIS AND FOR THE
MOST PART MISSING THE AREA TO THE SOUTH. THE 31.00Z ECMWF ALSO
SHOWS THIS AREA COMING OUT OF MISSOURI BUT TAKES IT FARTHER TO THE
NORTHWEST IMPACTING THE SOUTHERN AND EASTERN AREAS FROM LATE
MORNING THROUGH THE AFTERNOON. THE PREVIOUS FORECAST WAS TRENDED
TOWARD THE POSSIBILITY OF THIS CONVECTION COMING INTO THE AREA SO
HAVE MAINTAINED THESE TRENDS BUT LIMITED THE HIGHER RAIN CHANCES
TO THE SOUTHEAST SECTIONS OF THE FORECAST AREA. BY LATE IN THE
AFTERNOON AND INTO THE EVENING...ALL THE MODELS ARE SHOWING WHAT
LOOKS LIKE A DRY LINE/WIND SHIFT DEVELOPING AHEAD OF THE SURFACE
LOW AND MOVING EAST TOWARD THE AREA. THERE SHOULD BE ANOTHER SHORT
WAVE TROUGH ROUNDING THE UPPER LEVEL LOW TO PROVIDE DYNAMIC LIFT
OVER THIS DRY LINE/WIND SHIFT. BOTH THE 31.00Z NAM AND GFS SHOW A
JET CORE ALSO COMING AROUND THE UPPER LEVEL LOW WITH THE LEFT EXIT
REGION COMING OVER THE AREA TO ADD SOME AGEOSTROPHIC MOTIONS TO THE
FORCING FROM THE SHORT WAVE TROUGH. THIS SHOULD BE ENOUGH FORCING
TO CAUSE A LINE OF CONVECTION TO DEVELOP ALONG THIS DRY LINE AND
THEN WORK RAPIDLY EAST ACROSS THE AREA DURING THE EVENING. SOME
POTENTIAL FOR SEVERE TODAY...BUT THIS IS DEFINITELY NOT AS HIGH AS
THE PAST COUPLE OF DAYS. ML CAPES OF 1000 TO POSSIBLY AS MUCH AS
2000 J/KG SHOULD DEVELOP TODAY AHEAD OF THE DRY LINE. THE BEST
0-6KM SHEAR WILL BE WELL OUT AHEAD OF THE DRY LINE AND WILL LINE
UP BETTER WITH THE EXPECTED CONVECTION TO COME NORTHEAST OUT OF
MISSOURI. HOWEVER...THE 0-3 KM SHEAR SHOULD BE AROUND 30 KNOTS
AHEAD OF THE DRY LINE SO THE POTENTIAL FOR STORMS THIS AFTERNOON
AND EVENING TO PRODUCE DAMAGING WINDS AND HAIL. ALL THE ACTIVITY
SHOULD QUICKLY DIE DOWN AFTER MIDNIGHT AS IT MOVES OFF TO THE EAST
OF THE AREA. BOTH THE NAM AND GFS SHOW THE PRECIPITABLE WATERS
LOWERING DURING THE DAY AS DRIER AIR WRAPS IN FROM THE WEST. WHILE
ANY THUNDERSTORMS MAY PRODUCE SOME LOCALLY HEAVY RAIN...FEEL THAT
THE POTENTIAL FOR WIDESPREAD HEAVY RAINS TO PRODUCE FLASH FLOODING
IS NOT THERE TO SUPPORT THE NEED FOR ANOTHER FLASH FLOOD WATCH.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 329 AM CDT FRI MAY 31 2013
AT LONG LAST...THIS STUBBORN SYSTEM WILL BEGIN TO MAKE A MOVE TO
THE EAST SATURDAY. AS IT DOES...THE SURFACE LOW WILL MOVE FROM
CENTRAL MINNESOTA INTO NORTHERN WISCONSIN AS THE UPPER LEVEL LOW
BECOMES AN OPEN WAVE. THE LAST SHORT WAVE TROUGH WITH THIS SYSTEM
IS EXPECTED TO BE MOVING ACROSS THE AREA AND BE PRODUCING AROUND 8
PVU/S OF VORTICITY ADVECTION IN THE 500-300 MB LAYER. THIS FORCING
FROM THE WAVE COMBINED WITH BEING IN THE DEFORMATION AREA OF THE
SURFACE LOW SHOULD BE ENOUGH TO GENERATE SHOWERS ACROSS MUCH OF
THE AREA. MU CAPES SHOULD BE AROUND 200-300 J/KG IN THE AFTERNOON
WHICH WILL BE GOOD ENOUGH TO PRODUCE SOME ISOLATED THUNDER. THE
REMAINING SHOWERS SHOULD THEN MOVE OFF TO THE EAST SATURDAY NIGHT
WITH SUNDAY BEING THE FIRST DAY IN ABOUT A WEEK WITH NO CHANCE OF
RAIN. MONDAY ALSO LOOKS TO BE DRY WITH HIGH PRESSURE OVER THE AREA
BUT THEN THE RAIN CHANCES START TO RETURN FOR MONDAY NIGHT. THE
31.00Z GFS...GEM AND ECMWF ALL SHOW ANOTHER CLOSED LOW MOVING
TOWARD THE AREA FROM THE PACIFIC NORTHWEST. PLENTY OF DIFFERENCES
THOUGH ON HOW FAST THIS SYSTEM WILL START TO IMPACT THE AREA. THE
OPERATIONAL GFS IS THE FASTEST BRINGING THIS SYSTEM IN...EVEN
FASTER THAN ITS ENSEMBLE MEAN WHILE THE ECMWF IS THE SLOWEST. THIS
LOOKS TO BE ANOTHER SLOW MOVING SYSTEM KEEPING RAIN CHANCES IN THE
FORECAST FOR THE REMAINDER OF THE PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1201 AM CDT FRI MAY 31 2013
RECENT RAINS ACROSS THE UPPER MISSISSIPPI RIVER VALLEY REGION HAS
RESULTED IN SCT-BKN MVFR STRATUS...AFFECTING MOSTLY ALONG THE
MISSISSIPPI RIVER. HOWEVER...UNCERTAINTY EXISTS ON HOW LONG THE
STRATUS WILL HANG AROUND WITH A BREEZY SOUTHERLY WIND PERSISTING
TO HELP KEEP THINGS MIXED. FOR NOW HAVE INCLUDED A TEMPO GROUP
UNTIL 09Z FOR THE STRATUS...BUT AMENDMENTS MAY BE REQUIRED IF THE
STRATUS HANGS AROUND LONGER. TO THE WEST...A BAND OF SHOWERS AND A
FEW THUNDERSTORMS WAS TRACKING ACROSS SOUTHWEST MN AND NORTHWEST
IA AS OF MIDNIGHT. THESE ARE ON THE WANE...THOUGH...SO UNCERTAIN
DESPITE THERE NORTHEAST MOVEMENT THAT THEY CAN MAKE IT TO KRST
BEFORE DISSIPATING. HAVE LEFT THEM OUT OF THE KRST TAF FOR NOW.
A BRIEF PERIOD OF MVFR CONDITIONS LOOKS POSSIBLE BETWEEN 15-17Z
THIS MORNING...WHEN DAYTIME MIXING TAKES THE RECENT MOISTURE AND
HELPS FORM A LOW CUMULUS DECK. CEILINGS SHOULD RISE TO VFR AS
MIXING CONTINUES. HEADING INTO THE EVENING...INDICATIONS ARE THAT
A DRY-LINE WILL MOVE WEST TO EAST ACROSS THE TAF SITES...BRINGING
WITH IT POTENTIAL FOR A LINE OF SHOWERS AND THUNDERSTORMS. TRIED
TO TIME THIS BETWEEN 23-04Z. THERE COULD BE SEVERE WEATHER WITH
THIS LINE AS WELL...SOMETHING TO WATCH. OTHERWISE...VFR CONDITIONS
LOOK TO FOLLOW IN THE WAKE OF THE DRY-LINE AND EVENTUALLY A COLD
FRONTAL PASSAGE LATER IN THE EVENING.
ONLY OTHER ITEM OF NOTE IS THE WINDS WHICH LOOK TO GET GUSTY THIS
AFTERNOON WITH DAYTIME MIXING AHEAD OF THE DRY-LINE/COLD FRONT.
GUSTS AGAIN OF 20-25 KT FROM THE SOUTH ARE EXPECTED.
&&
.HYDROLOGY...
ISSUED AT 329 AM CDT FRI MAY 31 2013
TURKEY RIVER...
WITH THURSDAY BEING MUCH DRIER THAN EXPECTED IN NORTHEAST IOWA...THE
TURKEY RIVER IS COMING IN MUCH LOWER THAN ORIGINALLY ANTICIPATED.
ELKADER IS EXPECTED TO CREST AROUND 16.5 FEET. THIS IS ABOUT 2 FEET
LOWER THAN THE PREVIOUS FORECAST. THIS IN TURN WILL RESULT IN A MUCH
LOWER CREST FOR GARBER. THE RIVER HAS ALREADY CRESTED AROUND
22.1 FEET. IT SHOULD REMAIN AROUND THIS LEVEL THROUGH MUCH OF TODAY
AND THEN BEGIN A SLOW FALL.
UPPER IOWA...
DORCHESTER HAS FLATTENED OUT AROUND 13.4 FEET. WITH DECORAH
CONTINUING TO RISE UPSTREAM...EXPECT THAT DORCHESTER WILL ONCE AGAIN
START TO RISE THIS MORNING. CONSIDERING THE RAINFALL ACROSS THIS
BASIN ON THURSDAY STILL NOT QUITE SURE WHETHER THE CREST LATER THIS
AFTERNOON WILL BE ABOUT A HALF FEET /15.5 FEET/ HIGHER THAN ITS
PREVIOUS CREST OF 15 FEET ON THURSDAY MORNING. AM MORE INCLINED THAT
IT WILL COME IN WITH A SIMILAR AS THURSDAY MORNING.
KICKAPOO RIVER...
THE UPPER REACHES OF THE KICKAPOO HAVE ALREADY CRESTED AND STARTED
TO FALL RAPIDLY...THEREFORE...LA FARGE WILL BE ADJUSTED TO CREST
LOWER THAN EXPECTED /STILL BELOW FLOOD STAGE/
BLACK RIVER...
BLACK RIVER FALLS IS CONTINUING TO RISE RATHER RAPIDLY THIS MORNING.
LOOKING AT THE WATER UPSTREAM...THE NORTH CENTRAL RIVER FORECAST
CENTER IS EXPECTING IT TO NOW CREST AROUND 49.3 FEET LATER TODAY.
TREMPEALEAU RIVER...
DUE TO THE BROADER EXPANSE NEAR DODGE...EXPECT TO SEE A SLOW AND
STEADY RISE INTO THE WEEKEND. IT STILL LOOKS LIKE IT WILL CREST ON
SUNDAY AROUND 9.6 FEET.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION...AJ
HYDROLOGY...BOYNE
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
457 AM EDT SUN JUN 2 2013
.SYNOPSIS...WATER VAPOR IMAGERY AND RAP ANALYSIS SHOWS WLY FLOW
ALOFT AND A NARROW AREA OF DRY AIR ALOFT STILL AFFECTING THE CWA. A
LARGE SCALE TROUGH IN MID AND UPPER LEVELS CONTINUES TO PROGRESS
DOWNSTREAM FROM CENTRAL GREAT LAKES SW TO THE S CENTRAL U.S. WHERE
IT BECOMES BROAD AND WEAK. THE SRN PORTION OF TROUGH OVER THE LOWER
MS VALLEY IS WHERE SCT CONVECTION IS LOCATED ATTM. WEAK MID/UPPER
LEVEL RIDGING IS LOCATED OVER OUR FORECAST AREA AT THIS TIME. MEAN
1000-700 MB FLOW HAS TURNED MORE SLY AND PWATS HAVE INCREASED TO
NEAR NORMAL LEVELS PER 00Z JAX SOUNDING AT 1.53 INCHES. OTHERWISE...
PARTLY TO MOSTLY CLOUDY SKIES ACROSS THE CWA. SLY FLOW APPEARS TO BE
ENHANCING ISENTROPIC UPGLIDE ACROSS PARTS OF CWA WITH LOW STRATUS AT
TIMES WITH PATCHY FOG.
.SHORT TERM...
TODAY...WEAK FLOW IN THE MID LEVELS WITH LITTLE DYNAMIC FORCING FOR
CONVECTION AND STEERING FLOW IS GENERALLY S TO SW AT 5-10 MPH.
HOWEVER...MODEL SOUNDINGS SHOW THE SUBSIDENCE INVERSION QUITE A BIT
WEAKER TODAY AND WEAKER SELY LLVL WINDS. GIVEN THIS PATTERN AND
HIGHER PWAT AIR...RAIN CHANCES ARE HIGHER ACROSS THE ENTIRE CWA BUT
BEST CHANCES WILL GENERALLY BE ACROSS INLAND NE FL AS SELY FLOW
MEETS UP WITH A W COAST SEA BREEZE THAT WILL BE MORE ACTIVE.
MODIFIED SBCAPE TODAY ANYWHERE FROM ABOUT 1700-2600 J/JG AND LI -5
TO -6. MAIN ISSUE FOR AFTERNOON CONVECTION WILL BE GUSTY
WINDS...LIGHTNING AND LOCALLY HEAVY RAINFALL. RAIN CHANCES BECOME
ELEVATED ALONG THE ERN ZONES IN THE MORNING AND THEN PROCEED TO
INCREASE INLAND AREAS AS DAYTIME HEATING BECOMES MAXIMIZED AND SEA
BREEZES AND OUTFLOW MERGE. HIGHS WILL BE WARMER BY A COUPLE OF
DEGREES IN THE MID/UPPER 80S E ZONES TO NEAR 90 INLAND. NOT AS
BREEZY WITH ELY WINDS AROUND 15 MPH OVER THE COASTAL AREAS AND 5-10
MPH INLAND.
TONIGHT...ISOLD TO SCT CONVECTION ANTICIPATED IN THE 8PM-MIDNIGHT
TIME FRAME MAINLY OVER LAND AREAS. BEST CHANCES WILL BE NEAR AND W
OF HIGHWAY 301. PARTLY TO MOSTLY CLOUDY SKIES AND MOIST CONDITIONS
WILL ALLOW FOR MILD OVERNIGHT LOWS IN THE LOWER TO MID 70S. IN
ADDITION...LOW CLOUDS AND PATCHY FOG WILL BE POSSIBLE AFTER MIDNIGHT.
MONDAY AND TUESDAY...
WARM MOIST SOUTHWEST FLOW AHEAD OF AN APPROACHING MID LEVEL TROUGH
WILL RESULT IN NUMEROUS SHOWERS AND THUNDERSTORMS ON MONDAY. A FEW
STRONG STORMS WILL BE POSSIBLE AND CAPABLE OF STRONG DOWNBURSTS
AND LOCALLY HEAVY RAINFALL. MULTI-LAYERED CLOUDINESS AND RAIN
SHOULD KEEP TEMPS DOWN A BIT SO WE WILL LOWER TEMPS A COUPLE OF
DEGREES AND GO WITH HIGHS IN THE UPPER 80S INLAND AND MID 80S
COAST. THE MID LEVEL TROUGH AXIS WILL PIVOT ACROSS THE REGION
MONDAY NIGHT WHICH WILL ALLOW A FEW SHOWERS AND THUNDERSTORMS TO
CONTINUE OVER PORTIONS OF THE AREA THROUGH THE NIGHT.
NOW BEGINNING TO LOOK AS THOUGH DEEP LAYER MOISTURE WILL LINGER
ACROSS PORTIONS OF NORTHEAST FLORIDA ON TUESDAY...THUS WE WILL
INCREASE RAIN CHANCES TO 50-60% IN NORTHEAST FLORIDA ON TUESDAY.
SOME DRIER AIR ALOFT WILL KEEP POPS AT 30-40% ACROSS SOUTHEAST
GEORGIA. HIGHS ON TUESDAY WILL RANGE FROM THE LOW 90S ACROSS
INLAND SOUTHEAST GEORGIA TO THE UPPER 80S ACROSS OUR SOUTHERN
ZONES. WILL KEEP A LOW CHANCE OF RAIN GOING TUESDAY NIGHT AS
MOISTURE BEGINS TO INCREASE FROM THE SOUTH. WARM AND MUGGY
NIGHTTIME TEMPS WILL PREVAIL.
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
THE MEDIUM RANGE MODELS WITH THE 0Z RUN WERE FAIRLY SIMILAR IN
SHOWING A WEAK LOW PRESSURE SYSTEM MOVING NORTHEAST OUT OF THE
GULF OF MEXICO AND ACROSS THE FLORIDA PENINSULA DURING THE
THURSDAY NIGHT/FRIDAY TIMEFRAME. ALTHOUGH IT WILL DEPEND ON THE
EXACT TRACK OF THE LOW...PORTIONS OF THE AREA COULD SEE HEAVY
RAINFALL AND GUSTY WINDS LATE IN THE WEEK. WOULD LIKE TO SEE A
LITTLE MORE RUN TO RUN CONSISTENCY IN THE MODELS BEFORE HITTING
THIS TOO HARD. IN THE MEANTIME...WE WILL CONTINUE TO ADVERTISE A
40 TO 50 PERCENT CHANCE OF RAIN WEDNESDAY THROUGH FRIDAY.
SEASONABLY WARM AND HUMID CONDITIONS WILL CONTINUE.
&&
.AVIATION...LIFR CIGS MAY PERSIST AT GNV THROUGH 13Z WITH CIGS
BECOMING MVFR 13Z-17Z. FOR REST OF TAFS OCNL TO PREVAILING MVFR CIGS
EXPECTED THROUGH MID MORNING. OVERALL RAIN CHANCES ARE BETTER DURING
THE DAYTIME TODAY. IN FACT...APPEARS THERE IS A CHANCE OF SHOWERS
FROM ABOUT 11Z-16Z AS LLVL CONVERGENCE INCREASES OVER THE ERN ZONES
SO VCSH IN PLACE FOR JAX METRO TAFS AND SSI. SHOWERS AND POSSIBLE
STORMS COULD AFFECT GNV TAF IN THE AFTN WITH VCTS BY 18Z BUT THINK
ITS TOO EARLY TO INCLUDE TEMPO GROUP. VCSH HAS BEEN PLACED IN FROM
00Z TO 06Z TONIGHT.
&&
.MARINE...SEAS REMAIN AROUND 4-6 FT OFFSHORE EARLY THIS MORNING WITH
WITH ESE SWELL OF ABOUT 3-4 FT NEAR 8-9 SECONDS. WINDS AND SEAS
SHOULD GRADUALLY DECREASE TODAY AS RIDGE OVER THE WESTERN ATLANTIC
BEGINS MOVING EASTWARD WHILE A WEAKENING COLD FRONT APPROACHES FROM
THE NORTHWEST. A RELATIVELY WEAK PRESSURE PATTERN WILL RESULT IN
LIGHTER WINDS THROUGH THE FIRST HALF OF THE WEEK. AN INCREASE IN
WINDS IS EXPECTED DURING THE SECOND HALF OF THE WEEK BUT THE
STRENGTH OF THE WINDS WILL DEPEND ON THE TRACK OF AN AREA OF LOW
PRESSURE MOVING OUT OF THE GULF OF MEXICO IN THE THURSDAY/FRIDAY
TIMEFRAME. SMALL CRAFT ADVISORY WINDS WILL BE POSSIBLE.
RIP CURRENTS: A MODERATE TO HIGH RISK OF RIP CURRENTS TODAY DUE TO
PERSISTENT ONSHORE FLOW. MODERATE RISK LIKELY FOR MON DUE TO E TO SE
SWELLS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 90 70 88 69 / 40 30 70 60
SSI 83 74 84 74 / 30 20 60 60
JAX 87 71 87 71 / 40 20 60 60
SGJ 84 72 84 72 / 40 20 60 60
GNV 89 70 89 70 / 60 40 70 60
OCF 90 71 89 71 / 60 40 70 60
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
SHASHY/SHULER/
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
228 AM CDT SUN JUN 2 2013
.DISCUSSION...
308 PM CDT
CONVECTIVE TRENDS ARE THE MAIN FORECAST ISSUE THIS AFTERNOON. WILL
MAINTAIN FLASH FLOOD WATCH ACROSS SOUTHERN TIER OF COUNTIES
THROUGH ITS 00Z EXPIRATION.
SURFACE LOW PRESSURE WAS CENTERED OVER CENTRAL WI AT MID
AFTERNOON...WITH A COLD FRONT EXTENDING SOUTH THROUGH THE
MISSISSIPPI RIVER VALLEY THEN SOUTHWEST ACROSS MISSOURI. DESPITE
CONSIDERABLE CLOUD COVER NORTHWEST/WEST CENTRAL IL HAS DESTABILIZED
AS EXPECTED THIS AFTERNOON...WITH SCATTERED SHRA/TSRA DEVELOPING
ACROSS THE UIN-PIA-PNT AT 19Z. SPC RAP MESOANALYSIS GUIDANCE
INDICATES AN AXIS OF 500-1000 J/KG AND GENERALLY CONVERGENT LOW
LEVEL FLOW IN THAT REGION AHEAD OF THE SFC COLD FRONT...AND EXPECT
THAT THIS ACTIVITY WILL CONTINUE TO DEVELOP AND SPREAD NORTHEAST
OVER THE NEXT SEVERAL HOURS AIDED BY LARGE SCALE ASCENT ASSOCIATED
WITH SHORT WAVE TROUGH PROPAGATING ACROSS IA/MO PER GOES WATER VAPOR
IMAGERY. SUCCESSIVE RUNS OF THE HRRR HAVE MAINTAINED THE IDEA OF
SCATTERED STORMS/SMALL CLUSTERS LIFTING NORTHEAST THROUGH THE
CHICAGO METRO AREA THROUGH 23-01Z OR SO...BEFORE DIURNAL DECREASE IN
INSTABILITY WITH SUNSET RESULTS IN DECREASE IN COVERAGE THIS
EVENING. WHILE WIDESPREAD SEVERE WEATHER IS NOT ANTICIPATED...WITH
EFFECTIVE BULK SHEAR APPROACHING 30 KT AND DRIER AIR ALOFT...MAINLY
WEST WHERE A DCAPE AXIS OF 600-800 J/KG IS ANALYZED...WE COULD SEE A
FEW OF THE STRONGEST CELLS PRODUCE A LITTLE HAIL OR WIND DURING THE
REMAINDER OF THE AFTERNOON HOURS. ORGANIZED HEAVY RAINFALL SEEMS A
FAIRLY LOW PROBABILITY AT THIS POINT...THOUGH ANALYSIS/GUIDANCE
CONTINUES TO DEPICT PWATS NEAR 1.5 INCHES...BETTER LOW LEVEL
MOISTURE TRANSPORT AND SLIGHTLY SLOWER STORM PROPAGATION POTENTIAL
ACROSS THE SOUTHEASTERN COUNTIES OF THE CWA. SINCE A FLASH FLOOD
WATCH IS ALREADY IN PLACE THERE...AND WITH THESE AREAS HAVING
RECEIVED BETWEEN 2-3 INCHES OF RAINFALL IN YESTERDAY/LAST NIGHTS
MCS/S...ILL ALLOW THE WATCH TO RUN THROUGH ITS 00Z EXPIRATION.
COLD FRONT AND MID-LEVEL TROUGH AXIS PUSH ACROSS THE CWA THIS
EVENING...WITH DRIER AIR AND HEIGHT RISES SPREADING IN FROM THE WEST
OVERNIGHT. WEAKER SECONDARY FRONT TRAILS ACROSS THE AREA SUNDAY
MORNING HOWEVER...WITH MOST GUIDANCE RUNS INDICATING THE POTENTIAL
FOR A FEW SPOTTY SHOWERS MAINLY ACROSS EAST/SOUTHEAST PARTS OF THE
FORECAST AREA. BEYOND THAT...SURFACE HIGH PRESSURE WILL BUILD INTO
THE AREA LATER SUNDAY THROUGH MONDAY MAKING FOR A COUPLE OF DAYS OF
DRY AND COOLER WEATHER WITH AFTERNOON LAKE BREEZES. GUIDANCE
REASONABLE IN DEPICTING TEMPS IN THE MID/UPPER 60S SUNDAY...AND MID
60S TO LOWER 70S MONDAY...WITH LOWER 60S LIKELY ALONG THE LAKE
MICHIGAN SHORES. LOWS ARE EXPECTED TO BE IN THE 40S IN MANY AREAS
AWAY FROM THE CHICAGO METRO SPRAWL SUNDAY NIGHT AND AGAIN MONDAY
NIGHT.
UPPER LEVEL RIDGE AXIS DEVELOPS ACROSS THE REGION INTO TUESDAY...
WHILE CLOSED UPPER LOW CURRENTLY OFF THE BRITISH COLUMBIA COAST
MAKES ITS WAY INTO THE NORTHERN PLAINS. AS THIS OCCURS...THE SFC
HIGH OVER THE WESTERN LAKES WILL DRIFT TO THE EAST...WITH LOW LEVEL
FLOW MORE SOUTH-SOUTHEAST ACROSS THE PLAINS AND MISSISSIPPI VALLEY
BY MID-WEEK. THIS RETURN FLOW AND ASSOCIATED WARM/MOIST ADVECTION
WILL INITIALLY FOCUS ACROSS THE PLAINS AND INTO IA/MN
TUESDAY/TUESDAY NIGHT...BUT WILL SHIFT FARTHER EAST AND BRING
SHRA/TSRA CHANCES BACK TO OUR AREA LATER TUESDAY NIGHT AND
WEDNESDAY. SOME GUIDANCE HINTS AT A FEW SHRA/TSRA MOVING INTO OUR
NORTHWEST COUNTIES TUESDAY AFTERNOON...THOUGH THESE SHOULD BE
DECAYING AS THEY MOVE OUT OF THE BETTER FORCING/MOISTURE WEST OF THE
MISSISSIPPI AND HAVE MAINTAINED DRY FORECAST THROUGH THE DAY TUESDAY
WITH LOW CONFIDENCE OF ANY PRECIP OF SIGNIFICANCE MAKING IT THIS FAR
EAST. SHRA/TSRA CHANCES THEN INCREASE WEDNESDAY THROUGH THURSDAY AS
UPPER LOW AND INVERTED SURFACE TROUGH/COLD FRONT MOVE ACROSS THE
AREA. UPPER LOW FILLS AND OPENS UP DURING THIS TIME...WITH SOUTH
WARM/MOIST ADVECTION FLOW NOT TERRIBLY STRONG. SUSPECT THERE WILL BE
MANY DRY HOURS BETWEEN CLUSTERS OF SHRA/TSRA DURING THIS PERIOD.
TEMPS MODERATE BACK INTO THE LOW-MID 70S/NEAR NORMAL DURING THE
MID-WEEK PERIOD...THOUGH SOUTHEAST SYNOPTIC WINDS WILL KEEP WINDS
OFF THE LAKE PARTICULARLY ACROSS NORTHEAST IL.
SURFACE COLD FRONT SETTLES SLOWLY OFF TO THE SOUTH/SOUTHEAST OF THE
CWA THURSDAY NIGHT...THOUGH UPPER TROUGH AXIS LINGERS ACROSS THE
REGION INTO NEXT WEEKEND. HAVE HELD ONTO SOME SLIGHT CHANCE POPS
FRIDAY WITH THE TROUGH AXIS OVERHEAD AND THE ECMWF CONTINUING TO
SQUEEZE OUT QPF...THOUGH DRIER LOW LEVEL FLOW AROUND SFC HIGH
PRESSURE OVER THE NORTHERN LAKES SHOULD HELP MAINTAIN GENERALLY DRY
CONDITIONS BY FRIDAY NIGHT/SATURDAY. TEMPS DURING THE PERIOD
EXPECTED TO BE NEAR NORMAL...70S...THOUGH ONSHORE WINDS OFF THE BIG
POND WILL KEEP CONDITIONS COOLER NEAR THE LAKE.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* MVFR CIGS PROBABLE BEHIND COLD FRONT THIS MORNING.
* PERIOD OF IFR CIGS POSSIBLE...NAMELY IN THE 11Z-15Z FRAME.
* WIND SHIFT TO NE THIS AFTERNOON WITH LAKE BREEZE.
//DISCUSSION...UPDATED 06Z...
LOW PRESSURE ACROSS LOWER MI VERY EARLY THIS MORNING WILL DEPART
TO THE NORTHEAST WITH COLD AIR ADVECTION IN THE LOW-LEVELS
ENVELOPING THE AREA PRIOR TO DAYBREAK BEHIND A COLD FRONT. IN THE
IMMEDIATE POST FROPA AIRMASS UPSTREAM THERE ARE WIDESPREAD MVFR
CIGS WITH OCCASIONAL IFR...NAMELY IN NORTHERN WI. IF A MORE
NORTHERLY COMPONENT TO THE WIND WERE TO UNFOLD...WHICH COULD
OCCUR ALONG THE WESTERN SIDE OF LAKE MI...THEN THAT COULD USHER
THOSE IFR CIGS CLOSE OR POSSIBLY TO ORD AND MDW BETWEEN MAINLY 11Z
AND 15Z. CIGS SHOULD LIFT ABOVE 1500 FT BY LATE MORNING/EARLY
AFTERNOON BUT LIKELY BE SLOW TO SCATTER THROUGH THE AFTERNOON. IN
ADDITION BEHIND THE FRONT THERE WILL BE AN INCREASE IN NORTHWEST
WIND SPEEDS. GUSTS TO AROUND 20 KT ARE POSSIBLE LOOKING AT
UPSTREAM OBS AND VAD WIND PROFILER DATA...AS SPEEDS OF 20 KT ARE
ALREADY OBSERVED AT 2K FT /AND LIKELY UNDER/. A LAKE BREEZE WILL
LIKELY DEVELOP TODAY INFLUENCING MDW AND GYY AND LIKELY ORD AND
LATE IN THE DAY DPA. HAVE GONE WITH WIND DIRECTION NEAR
CLIMATOLOGY FOR THIS.
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE IN WIND TRENDS.
* MEDIUM CONFIDENCE IN 1500 FT OR LOWER CIGS THIS MORNING BUT LOW
CONFIDENCE IN IFR OCCURRING AT ORD. MEDIUM CONFIDENCE IN TIMING.
* MEDIUM-HIGH CONFIDENCE ON WIND SHIFT TO NORTHEAST AND ITS TIMING
THIS AFTERNOON.
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY AND TUESDAY...VFR.
WEDNESDAY THROUGH FRIDAY...CHANCE OF SHRA/TSRA.
MTF/IZZI
&&
.MARINE...
226 AM CDT
THE MOST ACTIVE PERIOD OVER LAKE MICHIGAN IN THIS NEXT WEEK WILL BE
TODAY AS COLD AIR ADVECTION IN THE WAKE OF A DEEPENING DEPARTING LOW
WILL EXPAND DOWN THE LAKE THROUGH MIDDAY. THE COMBINATION OF THE
COOLER AIR PUSH AND A TIGHT PRESSURE GRADIENT WILL OFFER NORTHWEST
TO NORTH WINDS IN MAINLY THE 20-25 KT BALLPARK THOUGH CANT RULE OUT
A FEW HIGHER GUSTS. THE INDIANA NEAR SHORE WILL BE CLOSE TO SMALL
CRAFT CRITERIA TODAY GIVEN THOSE GUSTS. HIGH PRESSURE WILL QUICKLY
EXPAND IN TONIGHT ON THE WAKE OF THIS LOW. A WEAK TROUGH LOOKS TO
MOVE OVER THE LAKE SOMETIME WEDNESDAY OR WEDNESDAY NIGHT...WITH HIGH
PRESSURE THEN RETURNING FOR THE END OF THE WEEK.
MTF
&&
.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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WWW.TWITTER.COM/NWSCHICAGO
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1240 AM CDT SUN JUN 2 2013
.DISCUSSION...
308 PM CDT
CONVECTIVE TRENDS ARE THE MAIN FORECAST ISSUE THIS AFTERNOON. WILL
MAINTAIN FLASH FLOOD WATCH ACROSS SOUTHERN TIER OF COUNTIES
THROUGH ITS 00Z EXPIRATION.
SURFACE LOW PRESSURE WAS CENTERED OVER CENTRAL WI AT MID
AFTERNOON...WITH A COLD FRONT EXTENDING SOUTH THROUGH THE
MISSISSIPPI RIVER VALLEY THEN SOUTHWEST ACROSS MISSOURI. DESPITE
CONSIDERABLE CLOUD COVER NORTHWEST/WEST CENTRAL IL HAS DESTABILIZED
AS EXPECTED THIS AFTERNOON...WITH SCATTERED SHRA/TSRA DEVELOPING
ACROSS THE UIN-PIA-PNT AT 19Z. SPC RAP MESOANALYSIS GUIDANCE
INDICATES AN AXIS OF 500-1000 J/KG AND GENERALLY CONVERGENT LOW
LEVEL FLOW IN THAT REGION AHEAD OF THE SFC COLD FRONT...AND EXPECT
THAT THIS ACTIVITY WILL CONTINUE TO DEVELOP AND SPREAD NORTHEAST
OVER THE NEXT SEVERAL HOURS AIDED BY LARGE SCALE ASCENT ASSOCIATED
WITH SHORT WAVE TROUGH PROPAGATING ACROSS IA/MO PER GOES WATER VAPOR
IMAGERY. SUCCESSIVE RUNS OF THE HRRR HAVE MAINTAINED THE IDEA OF
SCATTERED STORMS/SMALL CLUSTERS LIFTING NORTHEAST THROUGH THE
CHICAGO METRO AREA THROUGH 23-01Z OR SO...BEFORE DIURNAL DECREASE IN
INSTABILITY WITH SUNSET RESULTS IN DECREASE IN COVERAGE THIS
EVENING. WHILE WIDESPREAD SEVERE WEATHER IS NOT ANTICIPATED...WITH
EFFECTIVE BULK SHEAR APPROACHING 30 KT AND DRIER AIR ALOFT...MAINLY
WEST WHERE A DCAPE AXIS OF 600-800 J/KG IS ANALYZED...WE COULD SEE A
FEW OF THE STRONGEST CELLS PRODUCE A LITTLE HAIL OR WIND DURING THE
REMAINDER OF THE AFTERNOON HOURS. ORGANIZED HEAVY RAINFALL SEEMS A
FAIRLY LOW PROBABILITY AT THIS POINT...THOUGH ANALYSIS/GUIDANCE
CONTINUES TO DEPICT PWATS NEAR 1.5 INCHES...BETTER LOW LEVEL
MOISTURE TRANSPORT AND SLIGHTLY SLOWER STORM PROPAGATION POTENTIAL
ACROSS THE SOUTHEASTERN COUNTIES OF THE CWA. SINCE A FLASH FLOOD
WATCH IS ALREADY IN PLACE THERE...AND WITH THESE AREAS HAVING
RECEIVED BETWEEN 2-3 INCHES OF RAINFALL IN YESTERDAY/LAST NIGHTS
MCS/S...ILL ALLOW THE WATCH TO RUN THROUGH ITS 00Z EXPIRATION.
COLD FRONT AND MID-LEVEL TROUGH AXIS PUSH ACROSS THE CWA THIS
EVENING...WITH DRIER AIR AND HEIGHT RISES SPREADING IN FROM THE WEST
OVERNIGHT. WEAKER SECONDARY FRONT TRAILS ACROSS THE AREA SUNDAY
MORNING HOWEVER...WITH MOST GUIDANCE RUNS INDICATING THE POTENTIAL
FOR A FEW SPOTTY SHOWERS MAINLY ACROSS EAST/SOUTHEAST PARTS OF THE
FORECAST AREA. BEYOND THAT...SURFACE HIGH PRESSURE WILL BUILD INTO
THE AREA LATER SUNDAY THROUGH MONDAY MAKING FOR A COUPLE OF DAYS OF
DRY AND COOLER WEATHER WITH AFTERNOON LAKE BREEZES. GUIDANCE
REASONABLE IN DEPICTING TEMPS IN THE MID/UPPER 60S SUNDAY...AND MID
60S TO LOWER 70S MONDAY...WITH LOWER 60S LIKELY ALONG THE LAKE
MICHIGAN SHORES. LOWS ARE EXPECTED TO BE IN THE 40S IN MANY AREAS
AWAY FROM THE CHICAGO METRO SPRAWL SUNDAY NIGHT AND AGAIN MONDAY
NIGHT.
UPPER LEVEL RIDGE AXIS DEVELOPS ACROSS THE REGION INTO TUESDAY...
WHILE CLOSED UPPER LOW CURRENTLY OFF THE BRITISH COLUMBIA COAST
MAKES ITS WAY INTO THE NORTHERN PLAINS. AS THIS OCCURS...THE SFC
HIGH OVER THE WESTERN LAKES WILL DRIFT TO THE EAST...WITH LOW LEVEL
FLOW MORE SOUTH-SOUTHEAST ACROSS THE PLAINS AND MISSISSIPPI VALLEY
BY MID-WEEK. THIS RETURN FLOW AND ASSOCIATED WARM/MOIST ADVECTION
WILL INITIALLY FOCUS ACROSS THE PLAINS AND INTO IA/MN
TUESDAY/TUESDAY NIGHT...BUT WILL SHIFT FARTHER EAST AND BRING
SHRA/TSRA CHANCES BACK TO OUR AREA LATER TUESDAY NIGHT AND
WEDNESDAY. SOME GUIDANCE HINTS AT A FEW SHRA/TSRA MOVING INTO OUR
NORTHWEST COUNTIES TUESDAY AFTERNOON...THOUGH THESE SHOULD BE
DECAYING AS THEY MOVE OUT OF THE BETTER FORCING/MOISTURE WEST OF THE
MISSISSIPPI AND HAVE MAINTAINED DRY FORECAST THROUGH THE DAY TUESDAY
WITH LOW CONFIDENCE OF ANY PRECIP OF SIGNIFICANCE MAKING IT THIS FAR
EAST. SHRA/TSRA CHANCES THEN INCREASE WEDNESDAY THROUGH THURSDAY AS
UPPER LOW AND INVERTED SURFACE TROUGH/COLD FRONT MOVE ACROSS THE
AREA. UPPER LOW FILLS AND OPENS UP DURING THIS TIME...WITH SOUTH
WARM/MOIST ADVECTION FLOW NOT TERRIBLY STRONG. SUSPECT THERE WILL BE
MANY DRY HOURS BETWEEN CLUSTERS OF SHRA/TSRA DURING THIS PERIOD.
TEMPS MODERATE BACK INTO THE LOW-MID 70S/NEAR NORMAL DURING THE
MID-WEEK PERIOD...THOUGH SOUTHEAST SYNOPTIC WINDS WILL KEEP WINDS
OFF THE LAKE PARTICULARLY ACROSS NORTHEAST IL.
SURFACE COLD FRONT SETTLES SLOWLY OFF TO THE SOUTH/SOUTHEAST OF THE
CWA THURSDAY NIGHT...THOUGH UPPER TROUGH AXIS LINGERS ACROSS THE
REGION INTO NEXT WEEKEND. HAVE HELD ONTO SOME SLIGHT CHANCE POPS
FRIDAY WITH THE TROUGH AXIS OVERHEAD AND THE ECMWF CONTINUING TO
SQUEEZE OUT QPF...THOUGH DRIER LOW LEVEL FLOW AROUND SFC HIGH
PRESSURE OVER THE NORTHERN LAKES SHOULD HELP MAINTAIN GENERALLY DRY
CONDITIONS BY FRIDAY NIGHT/SATURDAY. TEMPS DURING THE PERIOD
EXPECTED TO BE NEAR NORMAL...70S...THOUGH ONSHORE WINDS OFF THE BIG
POND WILL KEEP CONDITIONS COOLER NEAR THE LAKE.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* MVFR CIGS PROBABLE BEHIND COLD FRONT THIS MORNING.
* PERIOD OF IFR CIGS POSSIBLE...NAMELY IN THE 11Z-15Z FRAME.
* WIND SHIFT TO NE THIS AFTERNOON WITH LAKE BREEZE.
//DISCUSSION...UPDATED 06Z...
LOW PRESSURE ACROSS LOWER MI VERY EARLY THIS MORNING WILL DEPART
TO THE NORTHEAST WITH COLD AIR ADVECTION IN THE LOW-LEVELS
ENVELOPING THE AREA PRIOR TO DAYBREAK BEHIND A COLD FRONT. IN THE
IMMEDIATE POST FROPA AIRMASS UPSTREAM THERE ARE WIDESPREAD MVFR
CIGS WITH OCCASIONAL IFR...NAMELY IN NORTHERN WI. IF A MORE
NORTHERLY COMPONENT TO THE WIND WERE TO UNFOLD...WHICH COULD
OCCUR ALONG THE WESTERN SIDE OF LAKE MI...THEN THAT COULD USHER
THOSE IFR CIGS CLOSE OR POSSIBLY TO ORD AND MDW BETWEEN MAINLY 11Z
AND 15Z. CIGS SHOULD LIFT ABOVE 1500 FT BY LATE MORNING/EARLY
AFTERNOON BUT LIKELY BE SLOW TO SCATTER THROUGH THE AFTERNOON. IN
ADDITION BEHIND THE FRONT THERE WILL BE AN INCREASE IN NORTHWEST
WIND SPEEDS. GUSTS TO AROUND 20 KT ARE POSSIBLE LOOKING AT
UPSTREAM OBS AND VAD WIND PROFILER DATA...AS SPEEDS OF 20 KT ARE
ALREADY OBSERVED AT 2K FT /AND LIKELY UNDER/. A LAKE BREEZE WILL
LIKELY DEVELOP TODAY INFLUENCING MDW AND GYY AND LIKELY ORD AND
LATE IN THE DAY DPA. HAVE GONE WITH WIND DIRECTION NEAR
CLIMATOLOGY FOR THIS.
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE IN WIND TRENDS.
* MEDIUM CONFIDENCE IN 1500 FT OR LOWER CIGS THIS MORNING BUT LOW
CONFIDENCE IN IFR OCCURRING AT ORD. MEDIUM CONFIDENCE IN TIMING.
* MEDIUM-HIGH CONFIDENCE ON WIND SHIFT TO NORTHEAST AND ITS TIMING
THIS AFTERNOON.
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY AND TUESDAY...VFR.
WEDNESDAY THROUGH FRIDAY...CHANCE OF SHRA/TSRA.
MTF/IZZI
&&
.MARINE...
218 PM CDT
MODERATE SOUTHERLY WINDS ARE OCCURRING AHEAD OF AN AREA OF LOW
PRESSURE AND ITS ATTENDANT COLD FRONT WHICH ARE EXPECTED TO PASS
OVER THE LAKE TONIGHT. A BRIEF LULL IN THE WINDS MAY OCCUR WITH THE
FRONTAL TROUGH THIS EVENING...BUT THEN WINDS ARE EXPECTED TO
SHIFT TO NORTHWESTERLY AND RAMP BACK UP INTO THE 20 TO 25 KT RANGE
FOR MUCH OF THE LAKE OVERNIGHT. WINDS SHOULD COME DOWN THROUGH
THE DAY SUNDAY...REMAINING RELATIVELY LIGHT ON MONDAY WITH LAKE
BREEZES DEVELOPING. ANOTHER AREA OF LOW PRESSURE BEGINS TO TAKE
SHAPE OVER THE PLAINS LATE MONDAY INTO TUESDAY WITH SOUTHEASTERLY
WINDS FRESHENING UP TO PERHAPS 15 TO 20 KT AT TIMES THROUGH
THURSDAY. THURSDAY NIGHT...THE LOW WEAKENS AS IT PASSES SOUTH OF
THE LAKE WITH WINDS TURNING NORTHERLY FRIDAY THROUGH THE WEEKEND.
BMD
&&
.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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AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
415 AM CDT SUN JUN 2 2013
.SHORT TERM...
MOST ACTIVE PORTION OF THE FORECAST WILL BE OVER THE NEXT 12 TO 15
HOURS. SURFACE ANALYSIS SHOWS COLD FRONT DRAPED ACROSS SOUTH-CENTRAL
TEXAS...NORTHERN LA THROUGH EASTERN ARKANSAS AND POINTS FURTHER
NORTH. A LARGE CLUSTER OF SHOWERS AND EMBEDDED STRONGER
THUNDERSTORMS AHEAD OF THE FRONT HAS BEEN SURGING SOUTHWARD
OVERNIGHT. AT THIS POINT...THIS ACTIVITY HAS BECOME OUTFLOW DRIVEN
VS THE MEAN FLOW WHICH WOULD BE MORE EASTERLY. HRRR SEEMS TO BE THE
ONLY MESO MODEL THAT HAS BEEN HAVING A GOOD INITIATION. IT SUGGESTS
A WEAKENING TREND WILL CONTINUE AS THE LEADING EDGE MOVES SOUTH
ACROSS MS AND LA TOWARDS THE CWA. WHILE IN GENERAL THIS WILL LIKELY
BE THE CASE...THERE/S STILL SOME INSTABILITY IN PLACE OVER THE AREA
WHICH WILL ALLOW A FEW CELLS TO BURST UP TO STRONG CATEGORY WITH
STRONG GUSTY WINDS.
HAVE SLIGHTLY BUMPED UP POPS TODAY...MAINLY TO ACCOUNT FOR ACTIVITY
THAT SHOULD BE GOING ON THIS MORNING. AFTER IT DISSIPATES...
DEVELOPMENT OF AFTERNOON SHOWERS AND A FEW THUNDERSTORMS WILL STILL
BE POSSIBLE AS INSTABILITY REMAINS IN PLACE.
COLD FRONT WILL STILL BE PUSHING SOUTH THROUGHOUT THE NIGHT AND
SHOULD BE REACHING THE COAST BY 12Z MONDAY. HAVE TRIMMED POPS
FURTHER SOUTH FOR THE MORNING PERIOD SO THAT ONLY COASTAL PARISHES
AND OFFSHORE WATERS HAVE WORDING OF RAIN IN THE ZONES.
.LONG TERM...
WEAK UPPER LEVEL RIDGING WILL BUILD INTO THE AREA MID WEAK AS UPPER
TROUGH EJECTS. SUBSEQUENTLY...RAIN CHANCES WILL DROP OFF MONDAY
AFTERNOON THROUGH WEDNESDAY. IN ADDITION...DAYTIME HIGHS WILL BE ON
THE RISE AS HEIGHTS INCREASE. TEMPS SHOULD MAKE IT TO THE 90 TO 93
DEGREE MARK FAIRLY EASILY.
AN UPPER TROUGH WILL TRACK ACROSS THE UPPER MISSISSIPPI VALLEY IN
THE LATTER PORTION OF THIS WEEK. THIS WILL BREAKDOWN THE EAST SIDE
OF UPPER RIDGE OVER THE GULF COAST THUS ALLOWING FOR AFTERNOON
SHOWERS AND THUNDERSTORMS TO BEGIN DEVELOPING AGAIN.
MEFFER
&&.AVIATION...
AS HAS BEEN THE CASE FOR SEVERAL NIGHTS...THE OVERNIGHT AVIATION
PROBLEM WILL BE THE DEVELOPMENT OF LOW CLOUDS. SEEING SOME
DEVELOPMENT IN THE FL015-FL025 RANGE...MOST NOTABLY AT KHUM...AT
THIS TIME. EXPECT SCT-BKN CLOUDS TO BECOME WIDESPREAD ACROSS THE
AREA BY 09Z AND REMAIN THROUGH ABOUT 15Z. ONE OR TWO SITES WILL
LIKELY FALL INTO THE IFR RANGE...PROBABLY AT KMCB.
THE OTHER PROBLEM WILL BE THE TIMING OF CONVECTION ASSOCIATED
WITH THE FRONTAL BOUNDARY. CURRENT MOVEMENT APPEARS TO BE ABOUT
340/17 KTS. THIS WILL ALLOW CONVECTION TO REACH KMCB AND KBTR
SOMETIME AROUND SUNRISE...ALTHOUGH A STRAY SHOWER OR TWO COULD REACH
KMCB BEFORE THEN. EXPECT A WEAKENING TREND FROM WHAT IS BEING
OBSERVED AT THIS TIME. WILL LEAD INTO EVENT WITH MENTION OF
VCSH/VCTS AND CARRY ABOUT A 4 HOUR WINDOW WITH THE MAIN CONVECTION.
FOR NOW...WILL ONLY USE TEMPO GROUPS AT KMCB...KBTR AND KHDC. WILL
ADJUST LATER AS WE CAN BETTER ANTICIPATE TIMING AT TERMINALS FARTHER
SOUTH AND EAST. STILL NOT CONFIDENT ON EXACTLY HOW FAR SOUTHWARD
FRONT WILL MAKE IT ON SUNDAY BEFORE RUNNING OUT OF PUSH. WIND FIELD
WILL LIKELY BECOME RATHER WEAK TOWARD EVENING.
35
&&
.MARINE...
WIND FIELD IS CONSIDERABLY WEAKER THIS MORNING THAN IT HAS BEEN FOR
SEVERAL DAYS. WITH A WEAKENING COLD FRONT ANTICIPATED TO MOVE INTO
THE AREA TODAY...WIND FIELDS WILL BECOME EVEN LIGHTER. WIND
DIRECTIONS WILL BE RATHER VARIABLE...BUT GENERALLY WITH AN EASTERLY
COMPONENT. NOT EXPECTING WINDS TO BE MUCH ABOVE 10 KNOTS BEFORE
THURSDAY...WITH THE POSSIBLE EXCEPTION OF THE USUAL EVENING DIURNAL
MAXIMUM. EVEN THEN...DO NOT ANTICIPATE WINDS STRONG ENOUGH TO
REQUIRE HEADLINES. 35
&&
.DECISION SUPPORT...
DSS CODE...BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT.
MONITORING RIVER FLOODING.
MONITORING CONVECTIVE TRENDS.
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED
WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE TO HIGH RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 88 66 88 63 / 60 20 10 10
BTR 90 68 89 67 / 60 20 10 10
ASD 88 70 90 69 / 60 30 10 10
MSY 88 73 89 72 / 60 30 10 10
GPT 87 71 89 69 / 50 30 10 10
PQL 87 71 88 68 / 50 30 10 10
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
343 AM EDT SUN JUN 2 2013
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE WEST TODAY...THEN PASS THROUGH
THE AREA TONIGHT AND MONDAY. CANADIAN HIGH PRESSURE WILL BUILD IN
BEHIND THE FRONT THROUGH MIDWEEK. ANOTHER FRONT MAY APPROACH THE
MIDDLE ATLANTIC STATES AT THE END OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AREA REMAINS UNDER THE INFLUENCE OF OFFSHORE HIGH PRESSURE EARLY
THIS MORNING...WHILE A COLD FRONT WELL TO THE WEST ENTERS THE OHIO
VALLEY. A LINE OF SHOWERS WITH LOCALLY HEAVY RAINFALL OVER SERN
OHIO IS APPROACHING THE WV BORDER AS OF 0730Z...AND MAY IMPACT
EASTERN WV BY MID-MORNING IF IT HOLDS TOGETHER. HRRR ALSO
INDICATES POTENTIAL OF ADDITIONAL SHOWER ACTIVITY DEVELOPING AHEAD
OF THIS LINE AND MOVING INTO EASTERN WV OR WRN VA EARLIER IN THE
MORNING...BUT SO FAR THE MODEL HAS LARGELY OVERDONE THIS PRECIP
OVERNIGHT. NO LONGER EXPECTING PRE-DAWN PATCHY FOG...AS DEW POINT
DEPRESSIONS ARE MOSTLY AROUND 10 DEGREES AND PERSISTENT SLY FLOW
SHOULD PREVENT TEMPS FROM DROPPING ENOUGH THE REST OF THE NIGHT.
FOR SUNDAY...SURFACE COLD FRONT IS EXPECTED TO MOVE THROUGH THE
OHIO VALLEY...BUT STILL BE WEST OF THE FORECAST AREA BY THE END OF
THE AFTERNOON. A PRE-FRONTAL TROUGH IS EXPECTED TO DEVELOP AND
AMPLIFY OVER THE MID-ATLANTIC. MID-LEVEL CLOUD COVER IS EXPECTED
TO INCREASE FROM WEST TO EAST ACROSS THE FORECAST AREA...BUT IN
SPITE OF IT CAPE IS EXPECTED TO REACH 1000-2000 J/KG RANGE BY LATE
MORNING. WIND SHEAR WILL BE SUFFICIENT FOR STORM ORGANIZATION AS
THE MID-UPPER LEVEL JET STREAM APPROACHES FROM THE WEST. DYNAMICS
LOOK STRONGER ON THE 00Z MODEL RUNS THAN PREVIOUSLY...AND SPC HAS
EXTENDED THE SLIGHT RISK AREA SOUTHWARD TO INCLUDE THE ENTIRE CWA.
FLOW IS EXPECTED TO BE MAINLY UNIDIRECTIONAL...SO MAIN THREAT WILL
BE DAMAGING STRAIGHT LINE WINDS...ALTHOUGH LARGE HAIL IS ALSO
POSSIBLE. PWATS IN FORECAST SOUNDINGS RUNNING AROUND 1.5 TO 2
INCHES...SO LOCALIZED FLASH FLOODING WILL ALSO BE POSSIBLE.
FORECAST HIGHS WEIGHT MOST HEAVILY ON MOS BIAS CORRECTED
GUIDANCE...WITH HIGHS IN THE LOW TO MID 80S WEST OF THE BLUE RIDGE
AND IN THE UPPER 80S TO AROUND 90 EAST OF THE BLUE RIDGE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
COLD FRONT ENTERS THE CWA SUNDAY NIGHT. MODELS NOT YET CONSISTENT
ON ITS EASTWARD PROGRESS BY MONDAY MORNING...WITH GFS HAVING THE
FRONT THROUGH MOST OF THE AREA...ECMWF (12Z SUN) THE SLOWEST...AND
THE NAM IN BETWEEN. WILL CONTINUE WITH POTENTIAL FOR SHOWERS AND
TSTMS OVERNIGHT...WITH HIGHEST POPS EAST OF I-95 CORRIDOR. LOW
TEMPS RANGE FROM THE LOW 60S OVER THE POTOMAC HIGHLANDS TO THE LOW
70S IN URBAN BALTIMORE/WASHINGTON.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
COLD FRONT WILL BE MOVING THROUGH THE POTOMAC HIGHLANDS BY MONDAY
MORNING. SHOWERS AND ISOLATED THUNDERSTORMS ARE POSSIBLE AHEAD OF
FROPA FOR AREAS ALONG AND EAST OF THE I-95 CORRIDOR THROUGHOUT THE
MORNING AND AFTERNOON. FURTHER SOUTH AND EAST...LOW LEVEL JET WILL
BECOME MORE PERPENDICULAR TO THE STORM MOTION AND HELP LEVITATE
HEAVY RAIN THAT WE MAY SEE SUNDAY EVENING. FCST SOUNDINGS WILL
STILL BE SATURATED WITH PWATS AT OR ABOVE 1.5 SO ISOLATED AREAS OF
HEAVY RAIN WILL STILL POSE A THREAT FOR SOUTHERN MARYLAND MONDAY
AFTERNOON WITHIN THUNDERSTORM ACTIVITY.
HIGH PRESSURE AND NW FLOW BEHIND FROPA WILL DROP DEWPTS AS IT MOVES
THROUGH THE MID ATLANTIC MONDAY NIGHT. CONTINENTAL AIR WILL BRING RELIEF
OF RECENT WARM SPELL FOR THE START OF NEXT WEEK WITH HIGH
TEMPERATURES NEAR OR SLIGHTLY BELOW NORMAL.
E-SE FLOW WILL BEGIN TUESDAY NIGHT AND USHER IN LOW LEVEL MOISTURE
INTO THE MID ATLANTIC AS HIGH PRESSURE MOVES OFF SHORE. LOW
PRESSURE FROM THE OHIO VALLEY WILL FORM ALONG A COLD FRONT AND MOVE
TOWARDS THE REGION BY THE END OF THE WEEK. REGION SHOULD STAY DRY
UNTIL THURSDAY NIGHT WHEN SHOWERS WILL OVERSPREAD THE AREA AS A
UPPER TROUGH MOVES CLOSER. MULTIPLE SHORTWAVE TROUGHS AND LOW
PRESSURE OFF THE ATLANTIC COAST MAY LEAD TO CLOUDY AND WET
CONDITIONS TOWARDS THE END OF THE WEEK AND START OF THE WEEKEND.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
EXPECT VFR CONDITIONS OVERNIGHT THROUGH MIDDAY SUNDAY.
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL DEVELOP
SUNDAY AFTERNOON INTO SUNDAY NIGHT AND WILL LIKELY BRING IMPACTS
TO THE TERMINALS. STORMS WILL HAVE THE POTENTIAL TO PRODUCE
DAMAGING WINDS...HAIL AND HEAVY RAINFALL. AMENDMENTS MAY BE
NECESSARY TO REFINE TIMING AND IMPACT OF SHOWERS/TSTMS. WINDS
GENERALLY SW 10-15KT...POSSIBLY GUSTY AT TIMES.
VFR CONDITIONS EXPECTED FOR THE START OF THE WORK WEEK WITH THE
EXCEPTION OF SOME ONGOING SHOWERS AT IAD-DCA-BWI-MTN MONDAY. WINDS WILL
SHIFT FROM THE SW TO THE NW BY MONDAY EVENING ACROSS ALL TERMINALS.
&&
.MARINE...
SCA CONTINUES EARLY THIS MORNING ON THE SOUTHERN CHES BAY WITH
GUSTS IN THE UPPER TEENS TO LOW 20S. SCA IS SCHEDULED TO EXPAND TO
ALL WATERS AT 14Z THIS MORNING. PRESSURE GRADIENT ON 00Z MODEL RUN
IS A LITTLE LESS THAN PREVIOUS RUNS...AND WIND DIRECTION IS
EXPECTED TO BE MORE SWLY THAN SOUTHERLY...WHICH WOULD INHIBIT
CHANNELING. AS SUCH...SCA CONDITIONS WILL LIKELY BE SOMEWHAT
MARGINAL...BUT WILL KEEP THE ADVISORY IN PLACE.
SHOWERS AND THUNDERSTORMS LATE THIS AFTERNOON AND EARLY EVENING
HAVE THE POTENTIAL TO PRODUCE STRONG WIND GUSTS...HEAVY RAIN AND
HAIL.
SHOWERS AND ISOLATED THUNDERSTORMS WILL BE ONGOING INTO THE START OF
THE WORK WEEK. WINDS WILL SHIFT FROM THE SW TO THE NW BY MONDAY
EVENING AS A COLD FRONT CROSSES.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 8 PM EDT THIS
EVENING FOR ANZ530>533-535>542.
SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ534-
543.
&&
$$
SYNOPSIS...KCS
NEAR TERM...KCS
SHORT TERM...KCS
LONG TERM...HAS
AVIATION...HAS/KCS
MARINE...HAS/KCS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
522 AM EDT SUN JUN 2 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 520 AM EDT SUN JUN 2 2013
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM
NW ONTARIO INTO THE CNTRL GREAT LAKES. A SHORTWAVE SUPPORTING OVER
NRN LAKE MICHIGAN INTO NW LOWER MI SUPPORTED AN AREA OF RAIN OVER
ERN UPPER MI THAT WAS SLOWLY SLIDING OFF TO THE EAST. SCT LIGHT
SHOWERS ALSO LINGERED OVER CNTRL UPPER MI. AT THE SFC...A TIGHT
GRADIENT BETWEEN LOW PRES OVER LAKE HURON AND A RIDGE INTO THE NRN
PLAINS SUPPORTED BRISK NRLY WINDS ACROSS LAKE SUPERIOR INTO THE
UPPER MI. UPSLOPE NRLY FLOW INTO THE HIGHER TERRAIN ALSO SUPPORTED
AREAS OF DRIZZLE. MUCH COLDER AIR HAS MOVED INTO THE REGION WITH
TEMPS DROPPING INTO THE UPPER 30S AND LOWER 40S.
TODAY...ALTHOUGH THE NAM AND HIGH RES MODELS SHOW LOW LEVEL
DRYING WILL SPREAD THROUGH MOST OF THE CWA THIS MORNING...UPSTREAM
CLOUDS TRENDS SUGGEST THAT THE CLEARING TREND MAY BE SLOWER. ANY
LINGERING LIGHT SHOWERS OR DRIZZLE SHOULD END BY MID OR LATE MORNING
WITH CLEARING FROM WEST TO EAST BY EARLY TO MID AFTERNOON. EVEN WITH
SUNSHINE...WITH N FLOW ACROSS LAKE SUPERIOR AND 850 MB TEMPS NEAR
-1C...TEMPS WILL STRUGGLE INTO THE UPPER 40S TO LOWER 50S NORTH AND
INTO THE MID AND UPPER 50S SOUTH.
TONIGHT...SFC HIGH PRES BUILDING INTO THE REGION FROM THE WEST
SUNDAY NIGHT WILL RESULT IN IDEAL RADIATIONAL COOLING CONDITIONS
OVER THE WESTERN INTERIOR OF THE CWA WHERE MIN TEMPS WILL LIKELY
FALL INTO LOWER 30S...NEAR THE LOWER END OF GUIDANCE.
SOME TRADITIONAL COLD SPOTS COULD ALSO SEE READINGS INTO THE UPPER
20S. SO...A FROST ADVISORY WAS ISSUED FOR INLAND PORTIONS OF THE WEST
HALF OF UPPER MICHIGAN. A VORTEX DESCENDING FROM NRN ONTARIO IS
EXPECTED TO GRAZE NE LAKE SUPERIOR. ALTHOUGH PCPN AND CLOUDS WITH
THIS FEATURE ARE EXPECTED TO REMAIN THE NE OF THE CWA...THE VORTEX
WILL RESULT IN NW WINDS STRONG ENOUGH TO MAINTAIN SOME BOUNDARY LAYER
MIXING AND PREVENT TEMPS FROM DROPPING OFF AS FAR AS IN THE WEST.
LOOK FOR MAINLY MID TO UPPER 30S MIN TEMPS OVER THE EAST HALF.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 343 AM EDT SUN JUN 2 2013
UPPER TROUGH THAT IS CURRENTLY AFFECTING THE UPPER GREAT LAKES
EARLY THIS MORNING WILL BE SHIFTING EAST THROUGH EASTERN CANADA ON
MONDAY. THIS WILL LEAD TO THE AREA BEING UNDER NORTHWEST FLOW ALOFT
AND A SURFACE HIGH PRESSURE RIDGE FROM A HIGH CENTERED IN SOUTH
CENTRAL CANADA. WITH DRY LOW AND MID LEVELS UNDER THE HIGH PRESSURE
RIDGE...EXPECT A MOSTLY SUNNY SKY ACROSS MUCH OF THE LAND AREA.
THERE COULD BE SOME LINGERING CLOUDS OVER NORTHEAST LAKE SUPERIOR
AND FAR EASTERN UPPER MICHIGAN AS THE UPPER TROUGH DEPARTS. WITH
THE SUNSHINE...EXPECT MIXING TO AROUND 850-825MB. BUT WITH
TEMPERATURES AT THAT LEVEL ONLY AROUND 2C WEST AND -1C EAST...BELOW
NORMAL HIGHS ARE EXPECTED AND ONLY IN THE 50S AND LOWER 60S. THE
COOLEST TEMPERATURES WILL BE ALONG THE GREAT LAKES SHORELINES DUE
TO LAKE BREEZES. THE OTHER ITEM TO MENTION FOR MONDAY WILL BE LOW
RH VALUES. ML DEWPOINTS FROM THE MODELS INDICATE VALUES IN THE MID
20S OVER THE INTERIOR LOCATIONS AND POTENTIALLY THE UPPER TEENS IF
THE GFS IS CORRECT. WITH THAT CONSISTENCY AND THE TRENDS IN THE
MAV/MET...HAVE LOWERED OUR DEWPOINTS A GOOD 5-7 DEGREES. THIS
PRODUCES RH VALUES OF 25-35 PERCENT OVER THE INLAND AREAS...WITH
THE LOWEST VALUES OVER THE WEST. FORTUNATELY...THE WET WEATHER
RECENTLY...GREEN UP WELL ON IT/S WAY OR EVEN DONE...AND BELOW NORMAL
TEMPERATURES REDUCES FIRE WEATHER CONCERNS EVEN WITH 10-15KT WINDS.
THE HIGH PRESSURE RIDGE WILL STILL BE OVER THE AREA ON MONDAY NIGHT
AS AN UPPER RIDGE SLIDES ACROSS THE AREA. THE CLEAR SKIES...LIGHT
WINDS...AND PWAT VALUES AROUND 30-40 PERCENT OF NORMAL WILL LEAD TO
A COLD NIGHT ACROSS THE AREA. WILL CONTINUE THE TREND OF GOING
BELOW GUIDANCE VALUES AND HAVE LOWS AROUND 30 OVER THE INTERIOR
LOCATIONS. RECORD LOWS FOR JUNE 4 ARE IN THE MID-UPPER 20S...SO
WE WILL BE CLOSE BUT LIKELY STAY ABOVE THE RECORD LOWS. WILL ALSO
CONTINUE THE MENTION OF FROST FOR MONDAY NIGHT ALONG WITH
HIGHLIGHTING IN HWO.
AREA WILL STILL BE UNDER THE INFLUENCE OF THE HIGH ON TUESDAY...AS
IT DRIFTS SOUTHEAST ACROSS THE CWA THROUGH THE DAY. THIS WILL LEAD
TO LIGHTER WINDS ACROSS THE AREA. DO EXPECT TO SEE SOME HIGH
CLOUDS STREAMING EAST ACROSS THE WESTERN CWA DURING THE
AFTERNOON AHEAD OF THE NEXT SYSTEM APPROACHING THE AREA. HIGHS WILL
BE A LITTLE WARMER ON TUESDAY...AS 850MB TEMPS WARM A COUPLE DEGREES
FROM MONDAY. WITH THE RIDGE LINGERING OVER THE EAST...HAVE LOWERED
TD VALUES SIGNIFICANTLY OVER THE EAST HALF. THIS WILL LIKELY LEAD TO
ANOTHER LOW RH DAY...BUT AS WITH MONDAY...FIRE WX CONCERNS ARE
LIMITED WITH EVEN LIGHTER WINDS.
THE UPPER TROUGH CURRENTLY OVER BRITISH COLUMBIA WILL BE MOVING
THROUGH THE NORTHERN PLAINS ON TUESDAY AND THEN BECOME CLOSE ENOUGH
TO START INFLUENCING THE UPPER GREAT LAKES FOR TUESDAY NIGHT AND
CONTINUING INTO THURSDAY. THERE ARE STILL QUESTIONS ON THE EXACT
TRACK OF THE SHORTWAVE TROUGH...WHICH IN TURN AFFECTS THE LOCATION
OF THE SURFACE LOW AND RESULTANT WARM AIR ADVECTION PRECIPITATION.
LATEST IDEA FROM THE GFS/ECMWF IS THAT MUCH OF THE INITIAL
PRECIPITATION WILL BE WEST OF THE AREA TUESDAY EVENING AND THEN
SLIDE OVER THE AREA TUESDAY NIGHT AND CONTINUE INTO WEDNESDAY NIGHT
AS THE SURFACE LOW/TROUGH SLIDES FROM THE DAKOTAS INTO SOUTHWEST
WISCONSIN. THE WARM AIR ADVECTION IS FAIRLY BROAD AND WEAK...SO
WOULD EXPECT THE PRECIPITATION TO BE GENERAL LIGHT SHOWERS. WITH
THE BEST FORCING FOCUSED OVER WISCONSIN AND THE SOUTHERN HALF OF THE
CWA...HAVE THE HIGHEST POPS IN THAT AREA. SINCE THE BULK OF THE
FORCING IS SOUTH OF THE AREA...WILL KEEP POPS IN THE HIGH CHANCE
CATEGORY SINCE IT IS ENTIRELY POSSIBLE MUCH OF THE RAIN STAYS IN
WISCONSIN. THUNDER CHANCES ARE LIMITED TO NON-EXISTANT...AS
SHOWALTER VALUES ARE WELL ABOVE ZERO AND MUCAPE VALUES STAY BELOW
100 J/KG DURING THIS PERIOD.
EXPECT A DIMINISHING TREND IN THE PRECIPITATION FOR THURSDAY INTO
THURSDAY NIGHT...AS THE DISTURBANCE SHIFTS EAST AND HIGH PRESSURE
NEAR HUDSON BAY PUSHES DRIER AIR INTO THE AREA. THIS SHOULD LEAD TO
DRY WEATHER FOR FRIDAY...BUT ANOTHER WEAK SHORTWAVE TRIES TO SLIDE
EAST ACROSS THE AREA FOR SATURDAY. WITH THE DRY EASTERLY FLOW AND
THE POTENTIAL THE HIGH REMAINS IN PLACE...IT/S ARRIVAL MAY BE
DELAYED SOME. TEMPERATURES FROM MID WEEK ON WILL CONTINUE THE BELOW
NORMAL TREND...WITH HIGHS GENERALLY IN THE 50S-60S AND THE COOLEST
DAY ON WEDNESDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 723 PM EDT SAT JUN 1 2013
EXPECT IFR CONDITIONS THIS EVNG ASSOCIATED WITH AN INFLUX OF SHALLOW
COOL...MOIST AIR ON THE HEELS OF GUSTY N WINDS TO IMPROVE TO MVFR
NW-SE LATE TNGT AS DRIER AIR FOLLOWS INTO THE AREA AHEAD OF HI PRES
BLDG TOWARD UPR MI. AS THIS HI MOVES OVHD ON SUN...CONDITIONS WL
IMPROVE TO VFR...AND THE GUSTY WINDS WL DIMINISH.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 520 AM EDT SUN JUN 2 2013
LOW PRESSURE OVER GEORGIAN BAY WILL SHIFT ENE INTO QUEBEC BY THIS
AFTERNOON...WHILE A RIDGE OF HIGH PRESSURE BUILDS OVER NORTHERN
ONTARIO. AS A RESULT...NORTH WINDS WILL DIMINISH TODAY. RIDGING WILL
EXTEND OVER LAKE SUPERIOR TONIGHT...WHICH WILL REMAIN THROUGH MUCH
WEDNESDAY AS THE NEXT LOW WILL SLIDES ACROSS THE NORTHERN PLAINS.
THE LOW WILL SHIFT SLOWLY E INTO THE MID MS VALLEY THURSDAY...WHILE
THE WEAK RIDGE OF HIGH PRESSURE LINGERS OVER LAKE SUPERIOR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
FROST ADVISORY FROM 2 AM EDT /1 AM CDT/ TO 8 AM EDT /7 AM CDT/
MONDAY FOR MIZ002-004-005-009>011-084.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
451 AM CDT SUN JUN 2 2013
.UPDATED FOR 12Z AVIATION DISCUSSION...
ISSUED AT 441 AM CDT SUN JUN 2 2013
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 342 AM CDT SUN JUN 2 2013
EARLY MORNING SURFACE ANALYSIS REVEALED A BROAD
RIDGE OF HIGH PRESSURE ACROSS THE DAKOTAS. THIS HIGH WAS LOCATED
BENEATH AN UPPER LEVEL RIDGE LOCATED JUST UPSTREAM OVER EASTERN
MONTANA. OVER THE NEXT 24 HOURS THIS HIGH WILL SLOWLY MIGRATE
EASTWARD BRINGING SOME MUCH ANTICIPATED DRY WEATHER.
HOWEVER...AFTERNOON TEMPERATURES WILL REMAIN COOL AS H850 TEMPS
LINGER IN THE 2 TO 4C RANGE. BOTH THE RAP AND NAM BUFR SOUNDINGS
SHOW MIXING UP TO AROUND 800MB WITH SATURATION AT THE TOP OF THE
BOUNDARY LAYER. THEREFORE USED THE MIXDOWN TOOL FOR HIGH
TEMPERATURES THIS AFTERNOON. ALSO INCLUDED SOME AFTERNOON CLOUDS
ACROSS THE SOUTHEASTERN HALF OF THE FORECAST AREA IN ANTICIPATION OF
SOME FLAT CU DURING PEAK HEATING. THESE CLOUDS WILL QUICKLY
DISSIPATE AFTER SUNSET SETTING THE STAGE FOR RADIATIONAL COOLING AND
ANOTHER CHILLY NIGHT ACROSS THE REGION.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 342 AM CDT SUN JUN 2 2013
NORTHWEST UPPER FLOW WILL PREDOMINATE THROUGH THE PERIOD... KEEPING
THINGS A BIT COOL ACROSS OUR AREA WITH NO REAL SEVERE WEATHER
CONCERNS. THERE ARE CERTAINLY SOME DIFFERENCES IN THE DETAILS
BETWEEN THE ECMWF AND GFS AND THEIR RESPECTIVE ENSEMBLES... BUT IN
GENERAL THERE IS GOOD AGREEMENT ON THE EVOLUTION OF THE LARGE
SCALE PATTERN THROUGH THE WEEK. ONE UPPER WAVE WILL SLOWLY MIGRATE
ACROSS THE AREA TUESDAY AND WEDNESDAY... WITH WEAK RIDGING FOR
THURSDAY INTO EARLY FRIDAY... THEN AN UPPER WAVE WILL SLOWLY WORK
IN FROM THE NORTHERN PLAINS AS WE MOVE INTO THE UPCOMING WEEKEND.
ALLOWED FOR SOME LOW POPS TO WORK INTO THE WESTERN PART OF THE
FORECAST AREA ON MONDAY AS WE GET ON THE BACKSIDE OF THE SURFACE
RIDGE AND START TO SEE SOME WARM ADVECTION DEVELOP OVER THE
WESTERN PART OF THE AREA. CHANCES FOR PCPN WILL THEN SPREAD
EASTWARD MONDAY NIGHT THROUGH TUESDAY AS A SURFACE LOW NEAR THE
NORTHERN END OF AN INVERTED TROUGH WORKS ITS WAY FROM THE DAKOTAS
ACROSS MICHIGAN. A LOOK AT 850-500MB DIFFERENTIAL THETA-E AND BEST
LIFTED INDICES SHOWS ELEVATED INSTABILITY SLIGHTLY LAGGING THE
INITIAL WARM ADVECTION AND MOISTURE RETURN... SO SHOULD SEE SHOWER
CHANCES AT FIRST GIVE WAY TO THE CHANCE FOR SHOWERS WILL SOME
EMBEDDED THUNDER. SEVERE WEATHER THREAT LOOKS LOW THROUGH THE WEEK
GIVEN GENERALLY MEAGER INSTABILITY UP INTO OUR AREA... WITH THE
MAIN BAROCLINIC ZONE REMAINING WELL TO THE SOUTH. HOWEVER... THERE
IS VERY STRONG DEEP LAYER SHEAR MIGRATING ACROSS ON TUESDAY AHEAD
OF THE AFOREMENTIONED SURFACE LOW... SO SHOULD INSTABILITY MANAGE
TO BE BETTER THAN THE FEW HUNDRED J/KG ADVERTISED BY THE NAM AND
GFS THEN THERE COULD BE SOME CONCERNS. HOWEVER... THE BETTER
SHEAR... BOTH LOW-LEVEL AND DEEP LAYER... LOOKS LIKE IT WILL
OUTPACE WHERE THE BETTER INSTABILITY WILL OCCUR ON TUESDAY...
WHICH SHOULD FURTHER MITIGATE ANY POTENTIAL. MAIN CONCERN IF
INSTABILITY WERE CLOSER TO 500 J/KG AND BETTER ALIGNED WITH SHEAR
WOULD BE LOW-TOPPED SUPERCELL POTENTIAL... BUT AT THIS POINT
THINGS DON/T APPEAR TO BE COMING TOGETHER TOO WELL FOR THAT.
PCPN CHANCES WILL LINGER ACROSS THE AREA TUESDAY NIGHT INTO
WEDNESDAY AS THE UPPER WAVE AND FILLING SURFACE LOW SLIDE ACROSS
THE AREA. A BIT OF A BACKDOOR COLD FRONT AND RIDGE OF HIGH
PRESSURE WILL WORK INTO THE AREA THURSDAY INTO FRIDAY... WHICH
SHOULD BRIEFLY REDUCE CHANCES FOR ANY PCPN OVER THE AREA.
HOWEVER... GIVEN THE ADVERTISED COOL 700-500MB TEMPERATURES AND
POTENTIAL FOR DECENT LAPSE RATES WITH ANY SUNSHINE... WE COULD
CERTAINLY WIND UP WITH SOME SHRA IF THERE ISN/T SUFFICIENT RIDGING
AND LOW LEVEL SUBSIDENCE. SO... WENT WITH LOWER OR NO POPS
THURSDAY AND FRIDAY FARTHER NORTH WHERE RIDGING LOOKS LIKE IT
SHOULD BE MORE PREVALENT... BUT KEPT SLIGHTLY HIGHER CHANCES
FARTHER SOUTH. DIDN/T INCLUDE ANYTHING FOR THURSDAY NIGHT... SINCE
IT SEEMS ANY POTENTIAL WOULD BE DIURNALLY DRIVEN. BY SATURDAY...
WE MAY SEE CHANCES FOR MORE WIDESPREAD PCPN START TO WORK IN FROM
THE WEST AS WE ONCE AGAIN GET ONTO THE BACKSIDE OF THE SURFACE
HIGH AND START TO SEE SOME WARM ADVECTION AND MOISTURE RETURN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 441 AM CDT SUN JUN 2 2013
MVFR STRATUS DECK HAS BEEN SLOW TO EXIT THE REGION...BUT SHOULD
CONTINUE TO SEE IT PUSH EASTWARD THIS MORNING. ONCE CONDITIONS
BECOME VFR...EXPECT THEM TO STAY THAT WAY THROUGH THE REST OF THE
PERIOD. A FEW AFTERNOON CLOUDS WILL DEVELOP ACROSS THE EAST...BUT
THEY WILL BE VFR. NNW WINDS WILL GO CALM OVERNIGHT...AND BECOME
SOUTHEASTERLY ACROSS WESTERN MINNESOTA BY MONDAY MORNING.
KMSP...
VFR CONDITIONS THROUGHOUT. CLOUDS ARE BEGINNING TO BREAK
UP...WITH CLEAR SKIES ACROSS THE NORTH. SHOULD SEE SOME AFTERNOON
CLOUDS AT OR ABOVE 4500FT THIS AFTERNOON. WINDS WILL GO CALM
OVERNIGHT AND BE SOUTHEASTERLY BY MID MORNING ON MONDAY.
/OUTLOOK FOR KMSP/
MON...VFR WITH -SHRA LATE. WINDS SE AT 10KTS.
TUE...MVFR WITH -SHRA/TSRA LIKELY. WINDS ESE AT 10G20KTS.
WED...VFR WITH MVFR/TSRA POSSIBLE. WINDS NNE AT 10KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...JRB
LONG TERM...
AVIATION...JRB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
359 AM CDT SUN JUN 2 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 342 AM CDT SUN JUN 2 2013
EARLY MORNING SURFACE ANALYSIS REVEALED A BROAD
RIDGE OF HIGH PRESSURE ACROSS THE DAKOTAS. THIS HIGH WAS LOCATED
BENEATH AN UPPER LEVEL RIDGE LOCATED JUST UPSTREAM OVER EASTERN
MONTANA. OVER THE NEXT 24 HOURS THIS HIGH WILL SLOWLY MIGRATE
EASTWARD BRINGING SOME MUCH ANTICIPATED DRY WEATHER.
HOWEVER...AFTERNOON TEMPERATURES WILL REMAIN COOL AS H850 TEMPS
LINGER IN THE 2 TO 4C RANGE. BOTH THE RAP AND NAM BUFR SOUNDINGS
SHOW MIXING UP TO AROUND 800MB WITH SATURATION AT THE TOP OF THE
BOUNDARY LAYER. THEREFORE USED THE MIXDOWN TOOL FOR HIGH
TEMPERATURES THIS AFTERNOON. ALSO INCLUDED SOME AFTERNOON CLOUDS
ACROSS THE SOUTHEASTERN HALF OF THE FORECAST AREA IN ANTICIPATION OF
SOME FLAT CU DURING PEAK HEATING. THESE CLOUDS WILL QUICKLY
DISSIPATE AFTER SUNSET SETTING THE STAGE FOR RADIATIONAL COOLING AND
ANOTHER CHILLY NIGHT ACROSS THE REGION.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 342 AM CDT SUN JUN 2 2013
NORTHWEST UPPER FLOW WILL PREDOMINATE THROUGH THE PERIOD... KEEPING
THINGS A BIT COOL ACROSS OUR AREA WITH NO REAL SEVERE WEATHER
CONCERNS. THERE ARE CERTAINLY SOME DIFFERENCES IN THE DETAILS
BETWEEN THE ECMWF AND GFS AND THEIR RESPECTIVE ENSEMBLES... BUT IN
GENERAL THERE IS GOOD AGREEMENT ON THE EVOLUTION OF THE LARGE
SCALE PATTERN THROUGH THE WEEK. ONE UPPER WAVE WILL SLOWLY MIGRATE
ACROSS THE AREA TUESDAY AND WEDNESDAY... WITH WEAK RIDGING FOR
THURSDAY INTO EARLY FRIDAY... THEN AN UPPER WAVE WILL SLOWLY WORK
IN FROM THE NORTHERN PLAINS AS WE MOVE INTO THE UPCOMING WEEKEND.
ALLOWED FOR SOME LOW POPS TO WORK INTO THE WESTERN PART OF THE
FORECAST AREA ON MONDAY AS WE GET ON THE BACKSIDE OF THE SURFACE
RIDGE AND START TO SEE SOME WARM ADVECTION DEVELOP OVER THE
WESTERN PART OF THE AREA. CHANCES FOR PCPN WILL THEN SPREAD
EASTWARD MONDAY NIGHT THROUGH TUESDAY AS A SURFACE LOW NEAR THE
NORTHERN END OF AN INVERTED TROUGH WORKS ITS WAY FROM THE DAKOTAS
ACROSS MICHIGAN. A LOOK AT 850-500MB DIFFERENTIAL THETA-E AND BEST
LIFTED INDICES SHOWS ELEVATED INSTABILITY SLIGHTLY LAGGING THE
INITIAL WARM ADVECTION AND MOISTURE RETURN... SO SHOULD SEE SHOWER
CHANCES AT FIRST GIVE WAY TO THE CHANCE FOR SHOWERS WILL SOME
EMBEDDED THUNDER. SEVERE WEATHER THREAT LOOKS LOW THROUGH THE WEEK
GIVEN GENERALLY MEAGER INSTABILITY UP INTO OUR AREA... WITH THE
MAIN BAROCLINIC ZONE REMAINING WELL TO THE SOUTH. HOWEVER... THERE
IS VERY STRONG DEEP LAYER SHEAR MIGRATING ACROSS ON TUESDAY AHEAD
OF THE AFOREMENTIONED SURFACE LOW... SO SHOULD INSTABILITY MANAGE
TO BE BETTER THAN THE FEW HUNDRED J/KG ADVERTISED BY THE NAM AND
GFS THEN THERE COULD BE SOME CONCERNS. HOWEVER... THE BETTER
SHEAR... BOTH LOW-LEVEL AND DEEP LAYER... LOOKS LIKE IT WILL
OUTPACE WHERE THE BETTER INSTABILITY WILL OCCUR ON TUESDAY...
WHICH SHOULD FURTHER MITIGATE ANY POTENTIAL. MAIN CONCERN IF
INSTABILITY WERE CLOSER TO 500 J/KG AND BETTER ALIGNED WITH SHEAR
WOULD BE LOW-TOPPED SUPERCELL POTENTIAL... BUT AT THIS POINT
THINGS DON/T APPEAR TO BE COMING TOGETHER TOO WELL FOR THAT.
PCPN CHANCES WILL LINGER ACROSS THE AREA TUESDAY NIGHT INTO
WEDNESDAY AS THE UPPER WAVE AND FILLING SURFACE LOW SLIDE ACROSS
THE AREA. A BIT OF A BACKDOOR COLD FRONT AND RIDGE OF HIGH
PRESSURE WILL WORK INTO THE AREA THURSDAY INTO FRIDAY... WHICH
SHOULD BRIEFLY REDUCE CHANCES FOR ANY PCPN OVER THE AREA.
HOWEVER... GIVEN THE ADVERTISED COOL 700-500MB TEMPERATURES AND
POTENTIAL FOR DECENT LAPSE RATES WITH ANY SUNSHINE... WE COULD
CERTAINLY WIND UP WITH SOME SHRA IF THERE ISN/T SUFFICIENT RIDGING
AND LOW LEVEL SUBSIDENCE. SO... WENT WITH LOWER OR NO POPS
THURSDAY AND FRIDAY FARTHER NORTH WHERE RIDGING LOOKS LIKE IT
SHOULD BE MORE PREVALENT... BUT KEPT SLIGHTLY HIGHER CHANCES
FARTHER SOUTH. DIDN/T INCLUDE ANYTHING FOR THURSDAY NIGHT... SINCE
IT SEEMS ANY POTENTIAL WOULD BE DIURNALLY DRIVEN. BY SATURDAY...
WE MAY SEE CHANCES FOR MORE WIDESPREAD PCPN START TO WORK IN FROM
THE WEST AS WE ONCE AGAIN GET ONTO THE BACKSIDE OF THE SURFACE
HIGH AND START TO SEE SOME WARM ADVECTION AND MOISTURE RETURN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1136 PM CDT SAT JUN 1 2013
CIGS ARE IMPROVING AREAWIDE AS DRIER BEGINS TO FILTER IN. SHOULD
SEE AN IMPROVEMENT TO VFR FROM CNTRL MN SOUTHEASTWARD INTO WRN WI
OVERNIGHT. VFR EXPECTED THEN FOR THE REMAINDER OF THE TAF CYCLE.
KMSP...CONDS AT TAF ISSUANCE TIME ARE VARYING FROM MVFR TO VFR.
UPSTREAM OBS INDICATE VFR CIGS...SO EXPECT CONDS TO IMPROVE TO VFR
QUICKLY AFTER TAF PERIOD BEGINS. WINDS WILL REMAIN NORTHWEST
AROUND 10 KTS THRU SUNDAY...THEN DIMINISH SUNDAY EVENING.
/OUTLOOK FOR KMSP/
MON...VFR WITH -SHRA POSSIBLE LATE. WINDS SE AT 10KTS.
TUE...MVFR WITH TSRA LIKELY. WINDS SE AT 10-15G20KTS.
WED...VFR WITH MVFR/TSRA POSSIBLE. WINDS NE 5 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...JRB
LONG TERM...
AVIATION...BORGHOFF
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
302 AM CDT SUN JUN 2 2013
.DISCUSSION...
MAIN FORECAST CHALLENGE WAS WHEN TO INCLUDE TSTM CHANCES AS
ANOTHER UPPER TROUGH/LOW MOVES FROM SWRN CANADA ACROSS NORTHERN
PLAINS THROUGH MIDWEEK.
FOR TODAY...UPPER RIDGE AHEAD OF SWRN CANADIAN LOW TO FLATTEN AS
IT BUILDS ACROSS CNTRL PLAINS AS UPPER LOW SOUTH OF HUDSONS BAY
DROPS SOUTH. PERSISTENT LOW CLOUDS HAVE CLEARED WRN ZONES AS OF
730Z AND SHOULD CONTINUE TO DO SO THROUGH THIS MORNING...ALTHOUGH
LATEST RAP SOUNDING DELAYED THIS CLEARING ALONG/E OF MO RIVER TILL
AFTERNOON. SLOWED CLEARING DOWN A BIT E...AND FURTHER ADJUSTMENTS
MAY BE NEEDED. MILDER TEMPS COMPARED TO SATURDAY BUT STILL BELOW
NORMAL AND GENERALLY A DEG OR TWO BELOW GUIDANCE BASED ON PERHAPS
HINDERED MIXING FROM MORNING/EARLY AFTN CLOUDS E AND/OR SLIGHTLY
COOLER H85 TEMPS PER 00Z ECMWF.
UPPER LOW MOVING TOWARD DAKOTAS LATE MONDAY WILL STRENGTHEN LOW
LEVEL JET LATE TONIGHT INTO MONDAY NIGHT. THIS WILL PROVIDE
INCREASING WINDS...ESPECIALLY MONDAY. HOWEVER...WINDS PROBABLY
WILL NOT INCREASE QUICKLY ENOUGH TONIGHT TO HELP LOWS MUCH WITH
GUIDANCE GENERALLY ACCEPTABLE. STORMS THAT DEVELOP TO OUR WEST
LATE TONIGHT AIDED BY THETA E ADVECTION IN LOW LEVEL JET AXIS
COULD MOVE ACROSS SECTIONS OF THE AREA MONDAY MORNING...FOR NOW
CONFINED SLGT CHC POPS TO FAR N. OTHERWISE KEPT MONDAY AFTN DRY.
BOOSTED WIND SPEEDS MONDAY TO JUST BELOW WIND ADVISORY CRITERIA
NWRN ZONES. MAX TEMPERATURES PROBABLY A CATEGORY OR SO WARMER
MOST AREAS LOOKS FINE.
INCREASING POPS MONDAY NIGHT INTO TUESDAY STILL ON TRACK AS UPPER
LOW SHIFTS SE A BIT AND LOW LEVEL JET/CONVERGENCE SHIFTS INTO THE
FORECAST AREA MONDAY NIGHT FOLLOWED BY A COLD FRONT TUESDAY.
ALTHOUGH SOME ADJUSTMENTS WERE MADE AND MORE WILL PROBABLY BE
ADDRESSED IN LATER FORECASTS...IT APPEARS HIGHER POPS WILL BE
SHIFTING TOWARD ERN ZONES THRU LATE TUESDAY. IF CLOUDS/SHOWERS
REMAIN WIDESPREAD TUE MAX TEMPS MAY NEED LOWERING.
CONFIDENCE IS LOW IN HOW SCENARIO TUE NIGHT/WED PLAYS OUT AS A
WAVE ROTATING AROUND UPPER LOW COULD HELP GENERATE MCS TO OUR WSW
IN UPSLOPE REGION ACROSS WRN HIGH PLAINS BY WED AM. SOME OF THIS
ACTIVITY COULD SKIRT AREA WED...SPCLY SOUTH...AND LOW CHC POPS
WERE CARRIED GENERALLY ALONG/S OF HIGHWAY 30. HOWEVER...WE COULD
ALSO SEE JUST MAINLY CLOUDS FROM THIS...BUT EITHER PRECIP OR
CLOUDS COULD IMPACT HIGHS. FOR NOW THEY WERE KEPT IN THE 70S TUE
AND WED.
THURSDAY LOOKED DRY WITH INCREASING TSTM CHANCES AGAIN FROM W TO E
FRIDAY INTO SATURDAY AS NEXT TROUGH APPROACHES. NO CHANGES MADE
FROM MODEL/PREVIOUS FORECAST BLEND.
CHERMOK
&&
.AVIATION...
06Z TAFS FOR KOMA...KLNK AND KOFK.
MVFR OR SLIGHTLY HIGHER CEILINGS AT KOMA AND KLNK SHOULD SCATTER
OUT BY 10Z-12Z AT KLNK AND AROUND 12Z-14Z AT KOMA...WITH VFR
CONDITIONS BEYOND THEN. NORTHWEST WINDS BECOMING NORTH THROUGH THE
DAY...THEN LIGHT AND VARIABLE AND BECOMING SOUTHEAST TOWARD THE
END OF THE TAF PERIOD.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1223 AM CDT SUN JUN 2 2013
.UPDATE...
ISSUED AT 710 PM CDT SAT JUN 1 2013
ONLY MADE A FEW FAIRLY MINOR TWEAKS TO THE FORECAST FOR THE EARLY
EVENING UPDATE. FIRST OF ALL...SLIGHTLY SLOWED THE DECREASE IN
WIND SPEEDS THIS EVENING...AS MANY SITES CONTINUE TO REPORT
SUSTAINED SPEEDS OF 20+ MPH...AND IT LOOKS LIKE SUSTAINED SPEEDS
TO AROUND 15 MPH MAY STILL BE PRESENT ACROSS MUCH OF THE EASTERN
1/2 OF THE CWA EVEN AT 10 PM WITH LOWER VALUES IN THE WEST...ALTHOUGH
ALL AREAS SHOULD LEGITIMATELY SETTLE TO AROUND/UNDER 10 MPH BY
MIDNIGHT OR SO AS HIGH PRESSURE CONTINUES BUILDING IN. GIVEN THAT
SUSTAINED SPEEDS ARE ALREADY SAFELY UNDER 30 MPH IN ALL
AREAS...WILL BE REMOVING WIND WORDING FROM THE HAZARDOUS WEATHER
OUTLOOK...RESULTING IN NO HAZARD MENTION FOR THE REST OF THE NIGHT
AS THE REGION CONTINUES ITS FAIRLY BRIEF RESPITE FROM THUNDERSTORM
ACTIVITY. THE OTHER TRICKY ISSUE FOR THE OVERNIGHT HOURS WILL BE
THE FATE OF THE LOW STRATUS DECK GENERALLY IN THE 3000-5000 FT
RANGE. CURRENT EXPECTATION IS FOR A STEADY EROSION OF THIS STRATUS
FROM WEST TO EAST AS THE EVENING GOES ON...MUCH IN LINE WITH
CURRENT FORECAST. HOWEVER...WILL HAVE TO SEE IF THE 21Z RAP MAY BE
ONTO SOMETHING WITH ITS 900 MILLIBAR RELATIVE HUMIDITY FIELD...AS
IT SUGGESTS THAT QUITE A BIT OF LOW CLOUD COVER COULD HANG ON OR
MOVE BACK INTO PRIMARILY THE EASTERN 1/2 OF THE CWA
TONIGHT...WHICH COULD OBVIOUSLY HAVE AT LEAST A SLIGHT IMPACT ON
OVERNIGHT LOW TEMPS. NO CHANGES MADE TO LOW TEMPS AT THIS
TIME...WHICH ARE STILL LOOKING TO AVERAGE AROUND 10 DEGREES BELOW
NORMAL IN THE LOW-MID 40S FOR MUCH OF THE CWA. HOWEVER...PLEASE
NOTE THAT FORECAST LOWS FOR OUR PRIMARY CLIMATE SITES GRAND
ISLAND/HASTINGS ARE STILL 5 DEGREES ABOVE RECORD LOWS FOR JUNE
2ND...WHICH FOR GRAND ISLAND IS 39 IN 1964...AND HASTINGS IS 40 IN
1964/1951.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 247 PM CDT SAT JUN 1 2013
UPPER AIR PROFILER AND SATELLITE DATA THIS AFTERNOON SHOWING THE
MAIN TROUGH AXIS CONTINUING TO GRADUALLY MAKE ITS WAY EAST/SOUTHEAST
THROUGH THE PLAINS...WITH NORTHWESTERLY FLOW BUILDING IN BEHIND. AS
EXPECTED...THIS DISTURBANCE BROUGHT A FEW SPRINKLES TO THE AREA
/MAINLY THIS MORNING/...AND HAS KEPT PLENTY OF CLOUD COVER AROUND
THROUGH THE DAY. HAS ALSO BEEN A BREEZY/WINDY DAY...WHILE SURFACE
LOW PRESSURE OVER MN/WI HAS BEEN SLOW TO SHIFT EAST...HIGH PRESSURE
HAS CONTINUED TO BUILD IN FROM THE WEST BEHIND THE MAIN FRONT. THIS
TIGHTENED PRESSURE GRADIENT RESULTED IN SUSTAINED WINDS OF 20 TO 30
MPH...AND AT TIMES GUSTS IN THE 40 MPH AREA. DID HAVE SOME SITES ON
OCCASION HITTING WIND ADV CRITERIA.
THROUGH THE REST OF THE SHORT TERM PERIOD...THE FORECAST REMAINS
DRY. MODELS REMAIN IN GOOD AGREEMENT IN THE UPPER LEVELS...SHOWING
BROAD RIDGING SETTING UP OVER THE ROCKIES/PLAINS...BETWEEN AREAS OF
LOW PRESSURE LOCATED OVER ONTARIO AND THE ID/MONT/CANADIAN BORDER
REGION. THIS WILL KEEP ANY PRECIPITATION CHANCES WELL OUT OF THE
CWA...AND HELP MAKE FOR A VERY PLEASANT SUNDAY.
AT THE SURFACE...THE PATTERN THROUGH THE SHORT TERM WILL BE
DOMINATED BY HIGH PRESSURE. THIS FEATURE WILL CONTINUE TO BUILD IN
FROM THE WEST TONIGHT...AND THERE IS A LITTLE UNCERTAINTY WITH JUST
HOW FAR EAST THE RIDGE AXIS WILL GET. THE NAM IS ON THE FURTHEST
EAST SIDE OF THINGS...SHOWING THE RIDGE AXIS ACTUALLY THROUGH THE
CWA BY 12Z SUNDAY...WITH MOST OF THE SUPPORT SHOWING THE RIDGE AXIS
STAYING JUST TO/SET UP OVER THE WRN FRINGE OF THE CWA. WINDS WILL
BE DIMINISHING WITH TIME...BUT DEPENDING ON WHERE THE RIDGE SETS UP
WILL DETERMINE WHETHER WINDS BECOME CALM...AND COULD AFFECT LOW
TEMPERATURES TONIGHT. STAYED FAIRLY CLOSE TO GUIDANCE FOR
LOWS...WHICH BRING LOWER/MID 40S TO THE CWA. IF THE WINDS STAY
UP...THIS MAY BE TOO COOL.
SUNDAY...SHOULD SEE PLENTY OF SUNSHINE ACROSS THE AREA...WITH THE
SURFACE HIGH KEEPING WINDS LIGHT. SHOULD START TO SEE AN INCREASE
IN TEMPS ALOFT STARTING TO SHIFT IN FROM THE WEST...AND HIGHS ARE
EXPECTED TO REACH INTO THE LOWER/MID 70S /COMBINED WITH DEWPOINTS
ONLY IN THE 40S/.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 247 PM CDT SAT JUN 1 2013
AS SFC RIDGE CONTINUES TO DEPART TO THE EAST AND SFC LOW DEEPENS
ALONG THE HIGH PLAINS...SOUTHERLY LLVL FLOW INCREASES SUNDAY
NIGHT. THE LLVL JET STRENGTHENS TO NEAR 50KTS AND IN INCREASING
SOUTHERLY FLOW...MOISTURE AGAIN IS DRAWN NORTH INTO THE PLAINS
STATES SUNDAY NIGHT/MONDAY. WARM FRONT LIFTS NORTHEAST ON MONDAY
AND TEMPS WILL TREND WARMER...CLOSER TO SEASONAL READINGS IN THE
UPPER 70S/LOW 80S. MONDAY WILL NOT BE WITHOUT WIND HOWEVER AS SFC
GRADIENT REMAINS TIGHT AND FORECAST SOUNDINGS SUGGEST MIXING TO AT
LEAST H8. WINDS DO NOT APPEAR TO REACH WIND ADV CRITERIA JUST YET...BUT
WILL NEED TO MONITOR. DURING THE DAY ON MONDAY SHOULD REMAIN
DRY...HOWEVER DID HOLD ONTO SOME LOW POPS IN THE WAA REGIME...BUT
GENERALLY EXPECT CAPPING TO HOLD IN THE EAST DURING THE AFTN WHILE
BETTER CONVECTIVE POTENTIAL/INITIATION FOCUSES TO THE WEST ALONG
THE HIGH PLAINS ALONG SFC TROUGH/DRYLINE EDGING INTO SW
NEB/WESTERN KANSAS...AND TO THE NW ALONG SFC TROUGH/COOL FRONTAL
BOUNDARY. CONVECTION IS THEN EXPECTED TO PUSH SOUTH AND EASTWARD
MONDAY NIGHT AS THE NORTHERN BOUNDARY REACHES CENTRAL NEBRASKA
AHEAD OF THE UPPER TROUGH IN THE DAKOTAS. AN INSTABILITY AXIS OF
2000 TO 2500 J/KG WILL REACH CENTRAL NEB MONDAY NIGHT WITH SHEAR
OF 30 TO 40KTS...AND SEVERE STORMS ARE POSSIBLE IN THIS
ENVIRONMENT MONDAY NIGHT...WITH HAIL/WIND PRIMARY HAZARDS FOR THE
MAINLY NOCTURNAL CONVECTION.
TUESDAY MAY SEE ONGOING CONVECTION IN THE MORNING WITH OUTFLOW
BOUNDARY AND/OR SFC WARM FRONTAL BOUNDARY POTENTIALLY STALLING
OUT...BUT THIS WILL BE DEPENDENT ON CONVECTION MONDAY NIGHT. MOISTURE
POOLS ALONG THE BOUNDARY ON TUESDAY WITH SREF INDICATING
INSTABILITY OF 3000 TO 4000 J/KG ACROSS NORTH CENTRAL KS WITH
INSTABILITY AXIS EXTENDING INTO SC NEB...WITH SHEAR ON THE ORDER
OF 40KTS. IF BOUNDARY POSITION IS CLOSE/ACROSS OUR CWA...STORMS
ARE EXPECTED TO INITIATE ACROSS OUR AREA TUESDAY AFTN/EVE IN VCNTY
OF BOUNDARY WITH SEVERE STORMS AGAIN LIKELY. SETUP WOULD BE
FAVORABLE FOR LARGE HAIL/DAMAGING WINDS/TORNADOES NEAR THE
BOUNDARY...AND HEAVY RAINFALL. ADDITIONAL CONVECTIVE DEVELOPMENT
IS POSSIBLE ALONG THE HIGH PLAINS/DRY LINE AREA AND TO THE NW WITH
APPROACHING TROUGH/SECONDARY COOL FRONT.
BEYOND THIS TIME FRAME...TOO DIFFICULT TO TRY TO NAIL DOWN THE
DETAILS AS BOUNDARY PLACEMENT WILL BE DEPENDENT UPON CONVECTION
WHICH DEVELOPS EACH DAY/NIGHT. ON WEDNESDAY...FRONT MAY LINGER IN
OUR SOUTHEAST ZONES...THEN BETTER CHCS FOR STORMS BEGIN TO SHIFT SE
ALONG BOUNDARY WHILE THE UPPER SYSTEM/LOW REACHES THE UPPER
MIDWEST. IN THEORY WE SHOULD SEE A LULL/BREAK IN CONVECTION
POTENTIAL FOR A PERIOD OR TWO...THEN PATTERN LOOKS ACTIVE AGAIN
HEADING INTO NEXT WEEKEND. FOR TEMPERATURES...IT IS NOT LOOKING
OVERLY WARM OR COLD...WITH HIGHS DEPENDENT UPON WHICH SIDE OF
BOUNDARY YOU ARE ON...BUT CLOSE TO SEASONAL NORMALS OVERALL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1213 AM CDT SUN JUN 2 2013
VFR CONDITIONS ARE FORECAST WITH LIGHT WIND THROUGHOUT THE
FORECAST. SOME STRAGGLING STRATUS NEAR 3500 FT WILL HANG AROUND
FOR PART OF THE OVERNIGHT...BUT WILL FINALLY CLEAR AS LOW PRESSURE
CONTINUES TO HEAD EAST AND A SURFACE HIGH BUILDS IN. LIGHT NORTH
WIND WILL BECOME LIGHT FROM THE SOUTH BY SUNDAY EVENING AS THE
SURFACE HIGH CONTINUES EAST AND THE FIRST OF THE RETURN FLOW
COMMENCES.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...PFANNKUCH
SHORT TERM...ADO
LONG TERM...FAY
AVIATION...HEINLEIN
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
153 AM EDT SUN JUN 2 2013
.SYNOPSIS...
UPPER DISTURBANCE WITH CONVECTION INTO SUNDAY. COLD FRONT CROSSES
SUNDAY NIGHT INTO MONDAY. COOLER AND DRIER TO START NEXT WEEK. WARM
FRONT THURSDAY.
&&
.NEAR TERM /THROUGH TODAY/...
WITH LOSS OF SUNSHINE...LOW-LEVEL AIRMASS HAS BEGUN TO BECOME LESS
UNSTABLE. THIS HAS BEEN SEEN IN THE STORMS IN OUR REGION DECREASING
IN INTENSITY. HOWEVER...A LINE OF STORMS HAS DEVELOPED TO OUR WEST
AND NORTHWEST.
EXPECT THIS LINE WILL GRADUALLY MOVE EAST WITH TIME AND HAVE
ADJUSTED ONSET OF LIKELY AND HIGHER POPS TO REFLECT THIS THINKING.
OTHERWISE...ONLY TWEAKS MADE.
PREVIOUS DISCUSSION...
PRIMARY FORECAST CONCERN CONTINUES TO REVOLVE AROUND
SHOWERS/THUNDERSTORM CHANCES AS WELL AS POTENTIAL FOR SEVERE
WEATHER.
REGARDING THUNDERSTORMS THIS AFTERNOON/EVENING...15Z REGIONAL RADAR
IMAGERY AND SFC OBS CONTINUE TO SHOW ONGOING WIDESPREAD
PRECIP...MAINLY IN THE FORM OF SHOWERS...FROM WESTERN OHIO SW-WARD
DOWN THE EXTENT OF THE OHIO RIVER INTO WESTERN TENN/ARKANSAS
RESULTANT OF STRONG OVERNIGHT CONVECTION. SFC TEMPS IN WHAT APPEARED
YESTERDAY TO BE THE FAVORED AREAS OF THUNDERSTORMS AND SUBSEQUENT
SVR WX INITIATION STILL ONLY IN THE MID/UPPER 60S GENERALLY...WITH
NO LIGHTNING STRIKES CURRENTLY. SHOULD PRECIP/CLOUDS HANG ON OVER
THAT AREA...STRONGER STORMS MAY WAIT TO FORM FURTHER EAST OVER
CENTRAL OHIO AND POINTS SOUTHWEST WHERE SFC TEMPS HAVE WARMED TO THE
UPPER 70S/LOW 80S DESPITE FAIRLY DENSE HIGH CLOUD COVER. GOOD
DYNAMICS ARRIVE BY 21Z WHICH CONTINUE INTO THE
EVENING...PARTICULARLY OVER THE WESTERN ZONES WHERE 30-40KTS OF
SHEAR IN PLACE. WITH THE FRONT STILL WELL TO THE WEST
HOWEVER...TOUGH CALL ON DETERMINING A TRIGGERING MECHANISM. A VORT
MAX PER LATEST RUC13 PROGGED TO PUSH NE-WARD THROUGH CENTRAL KY BY
21Z-00Z MAY BE ENOUGH TO GET THINGS GOING. DO FEEL THAT
THUNDERSTORMS WILL SLOWLY BEGIN TO FORM BY THE MID/LATE AFTERNOON
HOURS AT FIRST RELATIVELY UNORGANIZED...WITH A GRADUAL INCREASE FROM
THE WEST BY AND AFTER 00Z SUN. AS USUAL...IT APPEARS TO BE A RACE
BETWEEN STORM DEVELOPMENT AND LOSS OF DAYTIME PEAK INSTABILITY. BUT
IN THE END...SOME STORMS MAY BECOME STRONG TO SEVERE MAINLY ACROSS
THE FAR WESTERN ZONES CLOSER TO THE OHIO RIVER BUT THE THREAT
APPEARS MARGINAL AT BEST. STRONG WINDS APPEAR TO BE THE MAIN HAZARD
WITH DCAPE VALS OVER 1K J/KG JUST TO THE SOUTHWEST OF THE FORECAST
AREA BUT EL/S ARE SUFFICIENTLY TALL FOR SOME LARGE HAIL.
LITTLE CHANGE FROM PREV FORECAST WITH REGARD TO THE REMAINDER OF THE
OVERNIGHT HOURS. A MORE GENERAL CONVECTIVE RAINFALL WITH SOME
THUNDER PERHAPS WILL PUSH INTO THE AREA WITH GOOD DEEP LAYER
MOISTURE AND A PREFRONTAL TROUGH-TYPE FEATURE. STILL EXPECTING
ROUGHLY A HALF-INCH OR SO ACROSS THE AREA...AND SOME LOCALIZED WATER
ISSUES COULD BE POSSIBLE SHOULD HEAVY SHOWERS/STORMS PASS OVER THE
SAME LOCATION BUT NOTHING WIDESPREAD EXPECTED. SUNDAY...AGAIN LITTLE
CHANGE FROM PREV FCST WITH THE MAIN AXIS OF DEEP MOISTURE PUSHING
ACROSS DURING THE MORNING HOURS WITH HIGH CHANCE POPS CONFINED
MAINLY TO CKB-CRW AND POINTS EAST BY 18Z. ACTUAL COLD FRONT HOWEVER
STILL LAGS WELL BEHIND AND ONLY ENTERING THE NW ZONES BY END OF THE
PERIOD. INHERITED MAX TEMPS AROUND 80 FOR LOWLANDS STILL LOOK ON
TRACK.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY/...
GFS/ECMWF SHOW COLD FRONT OVER THE OH RIVER BY 00Z MONDAY. SHOWERS
AND STORMS WILL BE POSSIBLE ALONG THE FRONT...DIMINISHING IN
INTENSITY AND COVERAGE BY EARLY MONDAY MORNING.
THE FRONT BRINGS A WIND SHIFT FROM THE NORTHWEST ALOFT MONDAY
NIGHT...WHILE AT THE SFC COULD BECOME LIGHT AND VARIABLE...OR
CALM. THEN...FLOW BECOMES NORTHERLY LATER MONDAY AND MONDAY NIGHT
TO BRING COOLER TEMPERATURES...MILD AFTERNOON...AND RELATIVELY
COLDER NIGHTS ARE EXPECTED THROUGH TUESDAY NIGHT.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
WEAK SEMI ZONAL FLOW ALOFT AND NO VORT MAX FROM SHORTWAVES
SUGGEST BROAD HIGH PRESSURE WILL REMAIN IN CONTROL THROUGH EARLY
THURSDAY. THIS WILL CONTINUE TO CLEARING CONDITIONS...EXCEPT FOR
LOW LEVEL DIURNAL CU DURING THE AFTERNOON HOURS.
NEAR NORMAL TEMPERATURES EXPECTED THURSDAY ON. TWEAKED DOWN WPC
TEMPERATURE A BIT.
A WARM FRONTAL BOUNDARY FORMS ACROSS OH INTO SOUTHEAST OH
THURSDAY...UNDER SOUTHERLY FLOW. THE SOUTHERLY WINDS WILL ALSO
RESULT IN INCREASING LOW-LEVEL MOISTURE AND THE CHANCES FOR
SHOWERS AND STORMS...MAINLY DIURNAL IN NATURE...WILL ALSO RETURN
THROUGH THE REMAINDER OF THE PERIOD.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
06Z SUNDAY THRU 06Z MONDAY...
BAND OF ORGANIZED SHOWERS...WITH A FEW THUNDERSTORMS...WELL AHEAD OF
A COLD FRONT WILL MOVE EASTWARD ACROSS THE AREA OVERNIGHT AND SUNDAY
MORNING...REACHING THE I79 CORRIDOR BY 09Z...AND THE MOUNTAINS
AROUND 12Z. EXPECT MOST OF THE CONVECTION WILL BE IN THE SOUTHERN
AND CENTRAL MOUNTAINS BY 18Z...AND EXITING THE AREA BY 00Z MONDAY.
VFR CONDITIONS WILL GENERALLY PREVAIL OUTSIDE OF THE RAIN...WITH
GENERALLY MVFR CONDITIONS IN THE RAIN. AN EMBEDDED THUNDERSTORM IS
POSSIBLE...SO WILL USE VCTS IN TAFS. BEHIND THE MAIN BAND OF
CONVECTION...CANNOT RULE OUT A STRAY SHOWER OR STORM THIS AFTERNOON
AND EVENING.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z MONDAY...
FORECAST CONFIDENCE...MEDIUM.
ALTERNATE SCENARIOS: TIMING OF BAND OF CONVECTION AND MVFR CEILINGS
MAY VARY BY 2 OR 3 HOURS.
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 SUN 06/02/13
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 M M M M M M M
HTS CONSISTENCY H H M M M M M M M M M M
BKW CONSISTENCY H H H H H M M M M H H H
EKN CONSISTENCY H H H H H M H H H H H H
PKB CONSISTENCY H H H M H H H M M M H H
CKB CONSISTENCY H H H H H M H H H M M M
AFTER 06Z MONDAY...
IFR POSSIBLE IN SHOWERS AND THUNDERSTORMS SUNDAY NIGHT...AND IN
POST-RAIN FOG LATER SUNDAY NIGHT INTO MONDAY MORNING.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JMV/26
NEAR TERM...JSH/50
SHORT TERM...ARJ
LONG TERM...ARJ
AVIATION...JMV
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
136 AM EDT SUN JUN 2 2013
.SYNOPSIS...
WEATHER SYSTEM OVER THE WESTERN GREAT LAKES WILL SHIFT EASTWARD
TONIGHT...DRAGGING A COLD FRONT THROUGH THE OHIO VALLEY LATER
TONIGHT AND SUNDAY. THIS WILL PROMPT SEVERAL ROUNDS OF SHOWERS AND
STORMS FOR THE AREA...BEFORE A DRYING TREND TAKES HOLD FOR SUNDAY
NIGHT...LASTING INTO THE MIDDLE OF NEXT WEEK. A COOLER AND DRIER
AIRMASS WILL DOMINATE THROUGH THIS TIME PERIOD.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
STILL WORKING SOME DECENT UPDRAFTS NORTHEAST THROUGH SOUTH-CENTRAL
OHIO AND NORTHEAST KENTUCKY. A FEW STORM SPLITS...LEFT MOVING HAIL
CORES...AND PERSISTENT WEAK/BROAD ROTATION HAVE BEEN NOTED WITH
THE STRONGEST STORMS /PROMPTED ONE QUICK WARNING/. THESE WILL
CONTINUE TO WORK RATHER BRISKLY OFF TO THE NORTHEAST AND WHILE A
ROGUE SMALL HAIL/WIND GUST IS POSSIBLE...THINK THESE HAVE WEAKENED
IN A GENERAL SENSE FOR THE EVENING.
ATTENTION THEN TURNS TO THE STRONGER SYNOPTIC FORCING ENTERING
CNTL/ERN IL CURRENTLY WITH AN ATTENDANT COLD FRONT. RECENT HRRR
RUNS SIMPLY ADAMANT A WHOLE BUNCH OF SHOWERS/STORMS WILL DEVELOP
ACROSS EASTERN IND/WRN OHIO IN A FEW HOURS...AND DON/T WANT TO
TOTALLY DISCOUNT THIS AS IT HAS BEEN ONE OF THE FEW STEADIER
SIGNALS IN THE HRRR THE LAST FEW HOURS. BUT LAST GLIMPSES OF
SATELLITE VIS PICS OVER IND SHOW THAT THE STABLE AIRMASS IS INTACT
AND VERY FEW AGITATED CUMULUS/ACCAS ARE EVIDENT. THERE SHOULD BE A
MODEST RAMP-UP OF THE LOW LEVEL JET IMMEDIATELY DOWNSTREAM OF THE
PV ANOMALY ROTATING THROUGH IL RIGHT NOW SO THE SYNOPTIC SIGNALS
SAY TO STAY THE COURSE WITH HIGHER RAIN/STORM CHANCES BEGINNING
VERY LATE THIS EVENING. EARLY LOOK AT THE 02.00Z KILN BALLOON DATA
SUGGESTS INSTBY IS NOT IMPRESSIVE BUT WINDS/SHEAR CONTINUE TO BE
FAVORABLE FOR STORM ORGANIZATION. HOWEVER...SPC MESOA DATA
SUGGESTING THE DCAPE POOL HAS BEEN MODIFIED SOME AND NOW THE NEAR
SFC SHALLOW INVERSION HAS BEGUN TO FORM PER OBS. SO WHILE A FEW
SEVERE REPORTS ARE POSSIBLE OVERNIGHT...JUST NOT SEEING A GREAT
SETUP AND THUS WILL TONE BACK HAZ WX OUTLOOK FOR THE OVERNIGHT
PERIOD.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM MONDAY/...
SECONDARY WAVE ALOFT FINALLY ESCORTS THE TROUGH AXIS OUT OF THE
AREA TOMORROW AND THIS ALLOWS A WEAK SECONDARY FRONT TO DEVELOP
AND PUSH THROUGH DURING THE DAY. MAY BE A BROKEN BAND OF SHOWERS
ALONG THIS FEATURE BY MID AFTERNOON...SO CARRIED THIS CHANCE FROM
NW-SE ACROSS THE AREA DURING THE LATE MORNING INTO THE EARLY
EVENING. MUCH COOLER/DRIER AIRMASS ARRIVES ON THE HEELS OF THIS
FRONT AND MAKES FOR A COMFORTABLE SUNDAY NIGHT WITH LOWS DOWN INTO
THE 50S UNDER CLEARING SKIES.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
PERIOD BEGINS WITH HIGH PRESSURE CENTERED OVER THE UPPER MS VALLEY.
THE HIGH WILL BUILD SE INTO THE LOWER GREAT LAKES THROUGH TUESDAY.
HIGHS ON MONDAY WILL BE COOL...RANGING FROM THE UPPER 60S TO THE
LOWER 70S WHICH WILL BE ABOUT 5 TO 10 DEGREES BELOW NORMAL FOR EARLY
JUNE. TEMPERATURES WILL FALL INTO THE UPPER 40S TO LOWER 50S MONDAY
NIGHT. 12Z MODELS HAVE COME IN A LITTLE WARMER FOR TUESDAY. SO TOOK
A CONSENSUS FORECAST AND RAISED HIGHS FOR TUESDAY INTO THE LOWER TO
MID 70S.
ON WEDNESDAY THE SFC HIGH PRESSURE IS FORECAST TO SLIDE EAST. THE
ECMWF IS THE QUICKEST WITH THE RETURN PCPN...BUT THE REMAINING
MODELS KEEP THE FA DRY...SO LEANED TOWARDS THE MAJORITY.
WEDNESDAY NIGHT INTO THURSDAY AS WRMFNT DEVELOPS OVER THE OH VLY...
ATMOSPHERE BECOMES UNTIL STABLE AND IT LOOKS LIKE THERE WILL BE A
CHANCE OF SCT TSRA. THU NGT INTO FRI...H5 WAVE SWINGS UP THE OH VLY
ADDING EXTRA LIFT AND IT DRIVES A CDFNT ACROSS THE REGION KEEPING
CHC OF CONVECTION IN THE FORECAST. DRIER AIR TRIES TO BUILD IN FOR
SATURDAY.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
BAND OF SHOWERS AND THUNDERSTORMS EXITING THE AREA TO THE EAST
WILL LEAVE ALL TAF LOCATIONS DRY THROUGHOUT TONIGHT. A WEAK
FRONTAL BOUNDARY APPROACHING FROM THE WEST WILL BRING A MIX OF
VFR/MVFR CIGS TO THE AREA DURING THE EARLY MORNING. AFTER
SUNRISE...CIGS WILL RISE TO VFR ACROSS THE AREA. DURING THE
AFTERNOON...A SECONDARY COLD FRONT WILL PASS ACROSS THE AREA. THIS
FRONT WILL BE ACCOMPANIED BY A BRIEF CHANCE FOR SHOWERS WITH WINDS
SHIFTING FROM WESTERLY TO NORTHWESTERLY...GUSTING UP TO 25 KT.
WINDS WILL SUBSIDE LATE THIS EVENING WITH CLEARING EXPECTED TO
COMMENCE EARLY MONDAY MORNING.
OUTLOOK...NO SIGNIFICANT WEATHER EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...BINAU
NEAR TERM...BINAU
SHORT TERM...BINAU
LONG TERM...SITES
AVIATION...LATTO
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
543 AM EDT SUN JUN 2 2013
.SYNOPSIS...
WARM MOIST AIR OVER OUR REGION WILL BE DISPLACED BY A COLD FRONT
TODAY. BEHIND THE FRONT AN UPPER TROUGH WILL DOMINATE OUR REGION
WITH GENERALLY COOLER AND DRIER CONDITIONS PREVAILING THROUGH MID
WEEK. WET WEATHER WILL RETURN FOR LATE WEEK AS A NEW WEATHER
SYSTEM APPROACHES.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A LINE OF CONVECTION CONTINUES TO MOVE ACROSS MY NW MOUNT IAN
ZONES. THE MOST ORGANIZED ACTIVITY IS UP IN NY STATE...WITH THE
LINE BECOMING PROGRESSIVELY MORE RAGGED LOOKING DOWN INTO SWRN PA.
BIGGEST QUESTION FOR TODAY IS IF THE CONVECTION CAN ATTAIN ANY
MEASURE OF ORGANIZATION AS THE FRONT ENTERS THE REGION. SPS HAS
MUCH OF THE FCST AREA OUTLOOKED FOR A SLIGHT RISK OF SEVERE
STORMS...BUT AS USUAL MUCH WILL DEPEND ON HEATING. SHORT RANGE
HIGH RES GUIDANCE IS HAVING A HARD TIME GRASPING THE MODE OF
CONVECTION THAT WE CAN EXPECT WITH THE FRONT. THE RAP SHOWS
DISORGANIZED SHOWERS/STORMS WHILE THE HRRR HAS MORE OF A LINEAR
LOOKING FEATURE DEVELOPING OVER CENTRAL PA BY MID MORNING...BUT
CURIOUSLY WEAKENS THE LINE AS IT MOVES EAST DURING WHAT SHOULD
BECOME THE MOST UNSTABLE PART OF THE DAY. THIS DOES A LOT TO LOWER
CONFIDENCE IN TRYING TO TIME THE BEST CHANCES FOR RAIN AND STORMS
TODAY. AS FOR POPS...I ENDED UP GOING WITH A GMOS/SREF COMPROMISE
AND HAVE A LIKELY CHANCE OF SHOWERS AND THUNDER FOR MOST OF THE
AREA THIS MORNING INTO THIS AFTERNOON...BUT TIMING IS TOUGH.
IT WILL BE ANOTHER WARM MUGGY DAY WITH SLIGHTLY COOLER HIGH TEMPS
DUE TO SHOWERS AND CLOUD COVER. THIS SHOULD BE THE LAST
WIDESPREAD VERY WARM AND HUMID DAY FOR A WHILE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
STILL SOME UNCERTAINTY AMONG THE SHORT RANGE OPERATIONAL MODELS
AS TO THE TIMING OF THE FRONT THRU SERN PA LATER TONIGHT INTO
EARLY MONDAY. THE NAM IS THE SLOWEST WITH A WAVY FEATURE STILL
STUCK OVER SERN PA INTO EARLY MONDAY...WHILE THE GFS AND ECMWF
HAVE THE SURFACE FRONT ANYWHERE FROM THE CENTRAL DEL MARVA AREA TO
NORTHERN NJ. THE GEFS AND SREF FOLLOW THEIR OPERATIONAL
COUNTERPARTS PRETTY CLOSELY SO ONCE AGAIN I HAD TO SPLIT THE
DIFFERENCE AND KEPT THE SMALL MENTION OF SHOWERS GOING INTO MONDAY
MORNING. I DID DRY THINGS OUT THEREAFTER BUT THE 06Z NAM STILL
LEANS TOWARD THE 00Z SOLUTION OF A SLOWER WAVY FRONT...SO LATER
SHIFTS MAY HAVE TO ADJUST THIS A BIT.
DRIER AND COOLER AIR WILL MOVE IN FROM THE NW OVERNIGHT AND MONDAY
WITH THE LAST OF THE 60S DEWPOINTS BEING SHOVED OFF TO THE SE IN
TIME. HOW FAST THEY EXIT THE REGION ALTOGETHER WILL DEPEND ON THE
FRONT MENTIONED ABOVE.
HIGHS MONDAY WILL BE IN THE CHILLY 60S OVER THE NW...WELL BELOW
NORMAL FOR EARLY JUNE. HIGHS NEAR 80 IN THE SE WILL BE VERY NEAR
NORMAL.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
HIGH PRESSURE BUILDING DOWN OUT OF THE GR LAKES SHOULD PROVIDE FOR
SOME DRY UNEVENTFUL WEATHER TUESDAY WITH PLEASANT TEMPS AND
HUMIDITY.
AS THE HIGH MOVES OFF TO OUR NORTHEAST WE SHOULD SET UP A
SOUTHERLY FLOW OF INCREASING MOIST AIR. MEANWHILE THE MODELS WANT
TO CARVE OUT A BROAD SLOW-MOVING UPPER TROUGH OVER THE EASTERN US
SUGGESTING A PROLONGED PERIOD OF UNSETTLED WEATHER SETTING UP FROM
ABOUT MID WEEK...POSSIBLY INTO NEXT WEEKEND. I REINTRODUCED THE
CHANCES FOR RAIN BY WEDNESDAY AND KEPT THE MENTION OF SHOWERS
RIGHT INTO SUNDAY.
THE EXPECTED DEVELOPMENT OF A NEGATIVE NAO COULD SIGNAL THIS
EASTERN TROUGH STICKING AROUND FOR A WHILE WITH THE GEFS SHOWING
AN ANOMALOUS TROUGH DEVELOPING INTO THE LOWER GR LAKES OUT AS FAR
AS DAY 7.
OF NOTE IS SOME TROPICAL MOISTURE OVER THE BAY OF CAMPECHE. THE
NHC SAYS IT HAS NO CHANCE OF TURING INTO A TROPICAL CYCLONE OVER
THE NEXT COUPLE OF DAYS...BUT THE VARIOUS OPERATIONAL MODELS SEEM
TO WANT TO DRAG AT LEAST SOME OF THE MOISTURE NORTHWARD. AS USUAL
THERE IS NO AGREEMENT ON THE FINE DETAILS WITH THE GFS TAKING THE
SLUG OF MOISTURE OFF THE SERN US COAST...THE ECMWF TAKING THINGS A
FAIR DISTANCE UP THE COAST AND THE CANADIAN TAKING A FULL BLOWN
TROPICAL CYCLONE INTO THE CENTRAL APPALACHIANS BY FRIDAY. COULD BE
AN INTERESTING END OF THE WEEK.
&&
.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
AS EXPECTED...SOME SHOWERS INTO BFD. ACTIVITY HAS WEAKEN...BUT
A RUMBLE OF THUNDER STILL POSSIBLE.
EARLIER DISCUSSION BELOW.
BEST LLJ AND DYNAMICS LIFTING ACROSS THE LOWER LAKES AT THIS
POINT. BFD WILL LIKELY SEE SOME SHOWERS AND EVEN A THUNDERSTORM
OVERNIGHT.
AREAS TO THE EAST WILL HAVE LESS CHANCE...AS SFC CONVERGENCE
IS RATHER WEAK.
HAVE TO WATCH SUNDAY NIGHT...AS FRONT SLOWS. HEAVY RAIN WILL
BE POSSIBLE.
IMPROVING CONDITIONS LATER MONDAY...AS EDGE OF VERY DRY AIR
STARTS TO WORK INTO THE AREA.
OUTLOOK...
MON...LOW CIGS/FOG POSS EARLY OVR W MTNS.
TUE-WED...NO SIG WX EXPECTED.
THU...ISOLD PM THUNDERSTORM IMPACTS POSS W MTNS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LA CORTE
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
445 AM CDT SUN JUN 2 2013
.DISCUSSION...
A LINE OF THUNDERSTORMS IS BEGINNING TO FILL IN FROM SOUTH OF
LUFKIN TO COLLEGE STATION. RAIN GAUGES IN TRINITY COUNTY ARE
PICKING UP AS MUCH AS 2.2 INCHES IN 3 HRS AND AS MUCH AS 2 INCHES
OF THAT HAS FALLEN IN THE LAST HOUR. ALSO SEEING A SIGNS OF A REAR
INFLOW JET DEVELOPING IN THE BACK SIDE OF CONVECTION CLOSING IN ON
BRYAN/COLLEGE STATION. BASED ON IR IMAGERY SEEMS CLOUD TOPS ARE
COOLING MORE SO EXPECT DEEP CONVECTION TO CONTINUE THROUGH THE
MORNING. THE MAIN THREAT WILL BE HEAVY RAINFALL ON THE ORDER OF 2
TO 3 INCHES AN HOUR LIKE ALREADY OBSERVED. STORM MOTIONS ARE
EXPECTED TO BE SLOW AS IN 10 TO 2O MPH BUT COULD SEE CELLS
CONTINUE TO DEVELOP ALONG A FRONT PUSHING INTO THE AREA WHICH
COULD TRAIN ACROSS AREAS THAT HAVE ALREADY RECEIVED RAINFALL. SFC
ANALYSIS AT 09Z SHOWS FRONTAL BOUNDARY SLOWLY PUSHING SOUTH FROM
THE ARLATEX THROUGH C TX INTO THE NW HILL COUNTRY. LOOK FOR
CURRENT CONVECTION TO SLOWLY WORK SOUTH AHEAD OF THE FRONT AND
POSSIBLY OUT RUN IT BY A GOOD BIT. THE 00Z HIRES-WRF-ARW/TXTECH
WRF AND HRRR ALL SHOW CURRENT LINE OF CONVECTION WORKING SOUTH
THROUGH SE TX IN A BROKEN LINE. THE LINE THEN WEAKENS AS IT
APPROACHES THE COAST BETWEEN 15Z-18Z. DECIDED TO KEEP SOME 50/60
POPS THROUGH 12-15Z AND THEN GRADUALLY DECREASE RAIN CHANCES.
LOOKS LIKE THIS PART OF THE FORECAST MAY GO THROUGH ADDITIONAL
MODIFICATIONS DEPENDING ON HOW THE CONVECTION EVOLVES THIS
MORNING. DO THINK THIS CONVECTION SHOULD WORK OVER AND STABILIZE
THE ATMOSPHERE FOR THE AFTERNOON SO 20 POPS FOR THE AFTERNOON
LOOKS GOOD BUT IT COULD BE DRY.
AS IT HAS BEEN DISCUSSED BEFORE...MAIN HAZARD THIS MORNING WILL
BE HEAVY RAINFALL. UPPER LEVEL ANALYSIS SHOWS A TROUGH AXIS
WORKING THROUGH THE AREA AND THERE MAY BE ENOUGH UPPER LEVEL
SUPPORT TO KEEP CONVECTION GOING THIS MORNING. EXPECT UPPER LEVEL
ASCENT TO WEAKEN DURING THE AFTERNOON AND CONVERGENCE ALONG THE
FRONT TO WEAKEN AS WELL. THUS BEST CHANCES FOR HEAVY RAIN STILL
THIS MORNING AND THREAT DIMINISHING IN THE AFTERNOON. PRECIP WATER
VALUES THIS MORNING PEAK INVOF CONVECTION AROUND 1.8-2.0 INCHES
AND DECREASE THIS AFTERNOON TO BELOW 1.5 INCHES.
AS FOR THE REST OF THE FORECAST...MODELS STILL BRING WEAK FRONT
TO THE COAST AND POSSIBLY OFF THE COAST. EXPECT SFC DEWPOINT TEMPS
TO DROP INTO THE LOW 60S WHICH WILL SEEM QUITE A BIT DRIER THAN
THE MID 70S DEWPOINTS OF LATE. THIS ALSO MEANS SEASONABLE MIN
TEMPS IN THE MID 60S FOR MON/TUE. EXPECT DRY CONDITIONS TO PERSIST
AS UPPER LEVEL RIDGING BUILDS OVER S TX THROUGH MID WEEK. RIDGE
DOES SHOW SIGNS OF BREAKING DOWN AGAIN FOR THE END OF THE WEEK
WITH AN UPPER LOW OVER THE N PLAINS/MIDWEST/GREAT LAKES. THIS
INTRODUCES NW FLOW ALOFT OVER TX FOR THE END OF THE WEEK WHICH MAY
ALSO SUPPORT A WEAK FRONT MOVING INTO TX ALONG WITH A SERIES OF
WEAK SHORTWAVES THAT COULD INITIATE A FEW ROUNDS OF CONVECTION
ALONG THE RED RIVER AND N TX. POSSIBLE SOME OF THIS CONVECTION
COULD WORK INTO SE TX. WILL KEEP 20 POPS FOR THE END OF THE WEEK
WITH INCREASED MOISTURE AND FAVORABLE UPPER LEVEL PATTERN.
AS WITH TROPICAL SEASON WILL KEEP AN EYE ON CONVECTION IN THE BAY
OF CAMPECHE AND YUCATAN PENINSULA. BOTH GFS/ECMWF SUPPORT
CONVECTION BECOMING ORGANIZED AGAIN FROM REMNANTS OF BARBARA BY
TUESDAY. BOTH MODELS ALSO BRING THIS NEW SYSTEM INTO FLORIDA
THUR/FRI TIME FRAME. THERE WILL BE A DECENT AMOUNT OF WIND SHEAR
SO TOUGH TO KNOW HOW ORGANIZED THE SYSTEM WILL BECOME. NONETHELESS
ALL INDICATIONS ARE THAT THIS WILL NOT BE A THREAT FOR THE TX
COAST.
39
&&
.MARINE...
LIGHT ONSHORE FLOW SHOULD BECOME LIGHT AND VARIABLE BY THIS
AFTERNOON IN ADVANCE OF A WEAK COLD FRONT. LIGHT EAST TO SOUTHEAST
WINDS AND 1 TO 2 FOOT SEAS WILL BE THE PREVAILING CONDITION
THROUGH THE MAJORITY OF NEXT WEEK BECAUSE OF A VERY LIGHT PRESSURE
GRADIENT BEHIND THE FRONT. 44
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 89 64 92 68 93 / 30 10 0 0 0
HOUSTON (IAH) 91 67 92 69 93 / 50 10 0 0 0
GALVESTON (GLS) 87 75 88 76 88 / 50 10 0 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...39
AVIATION/MARINE...44
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1037 AM CDT SUN JUN 2 2013
.DISCUSSION...
ISSUED 1037 AM CDT SUN JUN 2 2013
MORNING SURFACE ANALYSIS SHOWS A WEAK TROUGH AXIS EXTENDING FROM
THE GREAT LAKES S/SW INTO CENTRAL ILLINOIS. 13Z HRRR SUGGESTS
ISOLATED SHOWERS WILL DEVELOP ALONG/AHEAD OF THIS FEATURE ACROSS
THE EASTERN HALF OF THE KILX CWA LATER THIS MORNING THROUGH THE
AFTERNOON. HAVE SEEN SOME WEAK RADAR ECHOES DEVELOPING WITHIN THE
PAST COUPLE OF HOURS...SO THIS SEEMS TO BE A PLAUSIBLE SOLUTION.
WILL THEREFORE MAINTAIN THE SLIGHT CHANCE POPS ALONG AND EAST OF A
BLOOMINGTON TO EFFINGHAM LINE. SKIES WILL REMAIN CLOUDY TODAY...AS
EVIDENCED BY CURRENT VISIBLE SATELLITE IMAGERY AND STRONGLY NEGATIVE
CU-RULE. DUE TO THE CLOUDS AND A COOL NORTHWESTERLY WIND...HIGH
TEMPS WILL REMAIN WELL BELOW NORMAL FOR THIS TIME OF YEAR. HAVE
TWEAKED AFTERNOON HIGHS DOWN A FEW DEGREES...WITH READINGS MAINLY
IN THE MIDDLE TO UPPER 60S. A FEW LOWER 70S WILL BE POSSIBLE SOUTH
OF I-70. ZONE UPDATE HAS ALREADY BEEN ISSUED.
BARNES
&&
.AVIATION...
ISSUED 640 AM CDT SUN JUN 2 2013
NOT MUCH OF A SHIFT IN THE FORECAST...AS BEHIND THE FRONTAL
PASSAGE...PLENTY OF MOISTURE IN THE BOUNDARY LAYER CONTRIBUTING TO
THE PERSISTENT STRATUS DECK MOVING ACROSS THE MIDWEST. MOSTLY
MVFR...WITH SOME TEMP SPOTS OF IFR. CIGS SLOWLY ON THE RISE WITH
THE WARMING OF THE DAY. LATER THIS AFTERNOON...GET INTO LESS
CYCLONIC FLOW ALOFT...AND SHOULD START TO SCATTER OUT. CHANCE FOR
SOME VC SH IN BMI CMI AND DEC...BUT LIKELY SO SCT THAT MENTION NOT
NEEDED AT THIS POINT. MAJOR CONCERN IS THE RIDGE MOVING OVHD IN
THE OVERNIGHT HOURS...WITH CLEARING SKIES AND LIGHT WINDS...MAY
SEE FOG DEVELOP. GUIDANCE NOT REFLECTING THE POTENTIAL...BUT
BUFKIT FAVORING FOG. FOR NOW...WILL START A TREND...AND WILL HAVE
TO WATCH THE XOVER TEMPS THROUGH THE AFTERNOON.
HJS
&&
.PREV DISCUSSION...
ISSUED 225 AM CDT SUN JUN 2 2013
COLD FRONT HAS PUSHED WELL TO THE EAST EARLY THIS MORNING. 2 AM
SURFACE MAP SHOWS A SECONDARY TROUGH SWINGING ACROSS THE NORTHWEST
PART OF ILLINOIS...AROUND LOW PRESSURE IN NORTHEAST LOWER
MICHIGAN. EXTENSIVE STRATOCUMULUS IS FOUND ALONG AND BEHIND THIS
TROUGH...WHILE SKIES HAVE BEEN CLEAR OVER THE EASTERN CWA THE PAST
FEW HOURS BETWEEN THE TROUGH AND FRONT.
THE MAIN FORECAST ISSUE FOR THIS PACKAGE INVOLVES MID WEEK RAIN
CHANCES.
SHORT TERM...TODAY THROUGH TUESDAY...
HAVE MAINTAINED SOME 20 PERCENT RAIN CHANCES ACROSS THE EASTERN
CWA TODAY AS THE TROUGH SWINGS THROUGH...BUT QUIET WEATHER WILL
GENERALLY PREVAIL THROUGH TUESDAY. 850 MB TEMPS FALLING INTO THE
LOW SINGLE DIGITS CELSIUS TONIGHT SHOULD ALLOW FOR SURFACE LOWS IN
THE UPPER 40S OVER ABOUT THE NORTHEAST HALF OF THE CWA...WITH
HIGHS IN THE UPPER 60S TO AROUND 70. AS SURFACE HIGH PRESSURE
SHIFTS EASTWARD ACROSS THE GREAT LAKES MONDAY NIGHT...DECENT WARM
AIR ADVECTION WILL OVERSPREAD THE CWA AND BRING HIGHS WELL INTO
THE 70S.
LONG TERM...TUESDAY NIGHT THROUGH SATURDAY...
EVENING MODEL GUIDANCE IN REASONABLE AGREEMENT WITH ZIPPING AN
UPPER TROUGH THROUGH THE NORTHERN AND CENTRAL PLAINS ON
TUESDAY...ASSOCIATED WITH A CLOSED SURFACE LOW CLOSER TO THE
CANADIAN BORDER. NOT TOO MUCH CHANGE NOTED WITH TRENDS OF
SPREADING RAIN CHANCES INTO AREAS WEST OF I-55 BY LATE TUESDAY
NIGHT. RATHER PERSISTENT EASTERLY FLOW ACROSS THE GREAT LAKES DOES
NOT BODE VERY WELL FOR DECENT PRECIP CHANCES IN THE EAST...AND
WILL GO WITH SLIGHT CHANCES THERE ON WEDNESDAY. MAIN TROUGH AXIS
SHOULD CROSS THE AREA LATE WEDNESDAY NIGHT THROUGH THURSDAY...
WHEN HIGHEST POPS OF 40 TO 50 PERCENT WILL BE IN THE FORECAST.
LATE IN THE WEEK...HAVE MAINTAINED SOME SLIGHT CHANCES FOR
FRIDAY. HOWEVER...GENERAL TREND SHOULD BE FOR DRY WEATHER INTO THE
FIRST HALF OF THE WEEKEND...WITH HIGH PRESSURE RIDGING SOUTHWEST
FROM THE GREAT LAKES.
GEELHART
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 7 PM CDT THIS EVENING FOR ILZ051.
&&
$$
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
1017 AM CDT SUN JUN 2 2013
.UPDATE...
LOOKING AT OVERALL RADAR TRENDS...HAVE ADJUSTED POPS FOR TODAY TO
REFLECT THE ONGOING CONVECTION OVER COASTAL LOUISIANA AND THE WEAK
MESOHIGH IN THE WAKE OF THE EARLY MORNING CONVECTION OVER THE
REMAINDER OF THE CWA. HAVE ALSO ADJUSTED CLOUD COVER TO REFLECT
OVERALL HIGHER AMOUNT OF SKY COVER THAN INITALLY ANTICIPATED. THE
RAIN COOLED STABLE AIRMASS COMBINED WITH THE CLOUD COVER HAS ALSO
ALLOWED FOR SLOWLY TEMPERATURE RECOVERY AND ADJUSTED DAYTIME HIGHS
DOWNWARD A FEW DEGREES. EXPECT TO SEE SOME RECOVERY THIS AFTERNOON
OF WARMTH AND MOISTURE WHICH WILL ALLOW FOR SOME REGENERATION IN
AREAS NOT COMPLETELY WORKED OVER THIS MORNING. GIVEN THIS...KEEP
LIKELY POPS IN PLACE FOR COASTAL LOUISIANA AND MISSISSIPPI...AND
ONLY HAVE CHANCE POPS ELSEWHERE. STILL EXPECT ACTUAL FRONTAL
PASSAGE TONIGHT...WITH A DRIER WEATHER REGIME TAKING HOLD FOR MUCH
OF THE WEEK. 32
&&
.PREV DISCUSSION... /ISSUED 415 AM CDT SUN JUN 2 2013/
SHORT TERM...
MOST ACTIVE PORTION OF THE FORECAST WILL BE OVER THE NEXT 12 TO 15
HOURS. SURFACE ANALYSIS SHOWS COLD FRONT DRAPED ACROSS SOUTH-CENTRAL
TEXAS...NORTHERN LA THROUGH EASTERN ARKANSAS AND POINTS FURTHER
NORTH. A LARGE CLUSTER OF SHOWERS AND EMBEDDED STRONGER
THUNDERSTORMS AHEAD OF THE FRONT HAS BEEN SURGING SOUTHWARD
OVERNIGHT. AT THIS POINT...THIS ACTIVITY HAS BECOME OUTFLOW DRIVEN
VS THE MEAN FLOW WHICH WOULD BE MORE EASTERLY. HRRR SEEMS TO BE THE
ONLY MESO MODEL THAT HAS BEEN HAVING A GOOD INITIATION. IT SUGGESTS
A WEAKENING TREND WILL CONTINUE AS THE LEADING EDGE MOVES SOUTH
ACROSS MS AND LA TOWARDS THE CWA. WHILE IN GENERAL THIS WILL LIKELY
BE THE CASE...THERE/S STILL SOME INSTABILITY IN PLACE OVER THE AREA
WHICH WILL ALLOW A FEW CELLS TO BURST UP TO STRONG CATEGORY WITH
STRONG GUSTY WINDS.
HAVE SLIGHTLY BUMPED UP POPS TODAY...MAINLY TO ACCOUNT FOR ACTIVITY
THAT SHOULD BE GOING ON THIS MORNING. AFTER IT DISSIPATES...
DEVELOPMENT OF AFTERNOON SHOWERS AND A FEW THUNDERSTORMS WILL STILL
BE POSSIBLE AS INSTABILITY REMAINS IN PLACE.
COLD FRONT WILL STILL BE PUSHING SOUTH THROUGHOUT THE NIGHT AND
SHOULD BE REACHING THE COAST BY 12Z MONDAY. HAVE TRIMMED POPS
FURTHER SOUTH FOR THE MORNING PERIOD SO THAT ONLY COASTAL PARISHES
AND OFFSHORE WATERS HAVE WORDING OF RAIN IN THE ZONES.
LONG TERM...
WEAK UPPER LEVEL RIDGING WILL BUILD INTO THE AREA MID WEAK AS UPPER
TROUGH EJECTS. SUBSEQUENTLY...RAIN CHANCES WILL DROP OFF MONDAY
AFTERNOON THROUGH WEDNESDAY. IN ADDITION...DAYTIME HIGHS WILL BE ON
THE RISE AS HEIGHTS INCREASE. TEMPS SHOULD MAKE IT TO THE 90 TO 93
DEGREE MARK FAIRLY EASILY.
AN UPPER TROUGH WILL TRACK ACROSS THE UPPER MISSISSIPPI VALLEY IN
THE LATTER PORTION OF THIS WEEK. THIS WILL BREAKDOWN THE EAST SIDE
OF UPPER RIDGE OVER THE GULF COAST THUS ALLOWING FOR AFTERNOON
SHOWERS AND THUNDERSTORMS TO BEGIN DEVELOPING AGAIN.
MEFFER
AS HAS BEEN THE CASE FOR SEVERAL NIGHTS...THE OVERNIGHT AVIATION
PROBLEM WILL BE THE DEVELOPMENT OF LOW CLOUDS. SEEING SOME
DEVELOPMENT IN THE FL015-FL025 RANGE...MOST NOTABLY AT KHUM...AT
THIS TIME. EXPECT SCT-BKN CLOUDS TO BECOME WIDESPREAD ACROSS THE
AREA BY 09Z AND REMAIN THROUGH ABOUT 15Z. ONE OR TWO SITES WILL
LIKELY FALL INTO THE IFR RANGE...PROBABLY AT KMCB.
THE OTHER PROBLEM WILL BE THE TIMING OF CONVECTION ASSOCIATED
WITH THE FRONTAL BOUNDARY. CURRENT MOVEMENT APPEARS TO BE ABOUT
340/17 KTS. THIS WILL ALLOW CONVECTION TO REACH KMCB AND KBTR
SOMETIME AROUND SUNRISE...ALTHOUGH A STRAY SHOWER OR TWO COULD REACH
KMCB BEFORE THEN. EXPECT A WEAKENING TREND FROM WHAT IS BEING
OBSERVED AT THIS TIME. WILL LEAD INTO EVENT WITH MENTION OF
VCSH/VCTS AND CARRY ABOUT A 4 HOUR WINDOW WITH THE MAIN CONVECTION.
FOR NOW...WILL ONLY USE TEMPO GROUPS AT KMCB...KBTR AND KHDC. WILL
ADJUST LATER AS WE CAN BETTER ANTICIPATE TIMING AT TERMINALS FARTHER
SOUTH AND EAST. STILL NOT CONFIDENT ON EXACTLY HOW FAR SOUTHWARD
FRONT WILL MAKE IT ON SUNDAY BEFORE RUNNING OUT OF PUSH. WIND FIELD
WILL LIKELY BECOME RATHER WEAK TOWARD EVENING.
35
MARINE...
WIND FIELD IS CONSIDERABLY WEAKER THIS MORNING THAN IT HAS BEEN FOR
SEVERAL DAYS. WITH A WEAKENING COLD FRONT ANTICIPATED TO MOVE INTO
THE AREA TODAY...WIND FIELDS WILL BECOME EVEN LIGHTER. WIND
DIRECTIONS WILL BE RATHER VARIABLE...BUT GENERALLY WITH AN EASTERLY
COMPONENT. NOT EXPECTING WINDS TO BE MUCH ABOVE 10 KNOTS BEFORE
THURSDAY...WITH THE POSSIBLE EXCEPTION OF THE USUAL EVENING DIURNAL
MAXIMUM. EVEN THEN...DO NOT ANTICIPATE WINDS STRONG ENOUGH TO
REQUIRE HEADLINES. 35
DECISION SUPPORT...
DSS CODE...BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT.
MONITORING RIVER FLOODING.
MONITORING CONVECTIVE TRENDS.
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED
WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE TO HIGH RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 81 66 88 63 / 50 20 10 10
BTR 82 68 89 67 / 50 20 10 10
ASD 83 70 90 69 / 70 30 10 10
MSY 82 73 89 72 / 70 30 10 10
GPT 84 71 89 69 / 70 30 10 10
PQL 86 71 88 68 / 70 30 10 10
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
32
AREA FORECAST DISCUSSION
NWS GRAY ME
1135 AM EDT SUN JUN 2 2013
.SYNOPSIS...
HIGH PRESSURE SHIFTS EAST TODAY WITH A COLD FRONT APPROACHING
FROM THE WEST. EXPECT SHOWERS AND THUNDERSTORMS TO DEVELOP TODAY
AHEAD OF THE FRONT WITH THE POTENTIAL TO PRODUCE STRONG WINDS AND
HEAVY RAIN. THE FRONT IS SLOW TO PUSH THROUGH THE AREA AND THERE
WILL BE A THREAT FOR MORE SHOWERS AND THUNDERSTORMS NEAR THE COAST
ON MONDAY. HIGH PRESSURE WILL BUILD SOUTHEAST OUT OF CANADA
THROUGH THE MIDDLE OF THE WEEK...BRINGING COOLER WEATHER BACK INTO
THE AREA.
&&
.NEAR TERM /TODAY/...
1130AM UPDATE... HAVE UPDATED THE FORECAST PRODUCTS TO INCLUDE
SEVERE THUNDERSTORM WATCH 271 FOR ALL OF NEW HAMPSHIRE AND MOST OF
WESTERN MAINE.
11AM UPDATE... MADE FURTHER ADJUSTMENTS TO HOURLY POP FORECAST TO
SHOW PROGRESSION OF PRECIPITATION CHANCES ACROSS THE AREA. LINE OF
STORMS HAS FORMED IN VERMONT AND IS MOVING INTO NEW HAMPSHIRE NOW.
OTHER CUMULUS HAS DEVELOPED OVER THE MOUNTAINS OF WESTERN MAINE
WHICH MAY LEAD TO THUNDERSTORM DEVELOPMENT AS WELL. SEVERE
THUNDERSTORM WATCH MAY BE NEEDED BY THIS AFTERNOON.
815AM UPDATE... HAVE MADE ADJUSTMENTS MAINLY TO HOURLY POP GRIDS
TO REFLECT THAT RAIN IS NOT EXPECTED NOW BUT CHANCES INCREASE
AFTER ABOUT 11AM. STILL EXPECTING SHOWERS AND THUNDERSTORMS TO
FORM ACROSS NEW HAMPSHIRE AND NORTHWEST MAINE LATE THIS MORNING OR
EARLY THIS AFTERNOON... WITH A LINE FORMING AND MOVING ACROSS THE
AREA THIS EVENING. STILL A THREAT FOR DAMAGING WINDS PRIMARILY.
7AM UPDATE... HAVE UPDATED GRIDS BASED ON CURRENT CONDITIONS
ACROSS MAINE/NEW HAMPSHIRE. BANDS OF SHOWERS AND STORMS THAT WERE
LOCATED ACROSS THE MOUNTAINS HAS WEAKENED AND SHIFTED NORTH.
MEANWHILE...A LARGE AREA OF PRECIPITATION WITH EMBEDDED CONVECTION
IS MOVING NORTHEAST INTO UPSTATE NEW YORK.
TIMING OF PRECIPITATION MAY NEED TO BE NUDGED FORWARD IN TIME A
COUPLE HOURS...HOWEVER LATEST HRRR RUN CONTINUES TO SHOW THE
CONVECTION REACHING THE MOUNTAINS OF MAINE AND WESTERN NEW
HAMPSHIRE BETWEEN 19Z- 20Z.
HAVE ADJUSTED CLOUDS BASED ON SATELLITE IMAGERY...DEW POINTS AND
TEMPERATURES THIS PACKAGE.
ORIGINAL DISCUSSION... A SLIGHT RISK FOR SEVERE THUNDERSTORMS
CONTINUES TODAY INTO THIS EVENING.
CONVECTION WILL REDEVELOP TODAY AHEAD OF AN APPROACHING COLD FRONT
AND PRE FRONTAL SURFACE TROUGH. STRONG WIND FIELDS WILL ALLOW FOR THE
POSSIBILITY OF DAMAGING WINDS...MAINLY IN BOWING OR LEWP SEGMENTS.
CANNOT RULE OUT THE POSSIBILITY OF HAIL IN ANY DISCRETE STORMS.
MID LEVEL LAPSE RATES DECREASE DURING THE DAY...AND WITH GOOD SOLAR
HEATING OVER SOUTHERN INTERIOR SECTIONS...CAPE VALUES WILL CLIMB
TO AT OR ABOVE 1000 J/KG...WITH A FEW FAR SOUTHERN INTERIOR AREAS
APPROACHING 2000 J/KG.
LOW LEVEL HELICITY VALUES WILL INCREASE DURING THE DAY AS WELL WHICH
MAY LEAD TO ISOLATED SUPERCELLS.
STORM MOTION WILL BE RELATIVELY RAPID...BUT WITH THE FRONT SLOWLY
OVER THE REGION...TRAINING ECHOES MAY LEAD TO LOCALLY HEAVY RAINFALL.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
THUNDERSTORMS WILL BE CONTINUING INTO TONIGHT AS SURFACE COLD
FRONT CONTINUES TO SLOW IN ITS FORWARD MOTION. FAR SOUTHERN
AREAS MAY HAVE YET ANOTHER ROUND OF SHOWERS AND STORMS MONDAY
MORNING AS MODELS CONTINUE TO SHOW A WEAKNESS IN THE SURFACE
FIELDS AND POSSIBLY THE DEVELOPMENT OF A WAVE OF LOW PRESSURE IN
THE GULF OF MAINE.
THE PRECIPITATION WILL ALLOW FOR A MOIST GROUND AND MORE PATCHY
FOG TO DEVELOP TONIGHT. USED OF A BLEND OF MAV/MET MOS FOR
OVERNIGHT MINS AND DAYTIME HIGHS ON MONDAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
THE COLD FRONT MOVES OFF THE COAST BY MONDAY EVENING ALLOWING
CLEARING BEHIND THE FRONT ON A DEVELOPING WNW DOWNSLOPING FLOW.
TUESDAY/WEDNESDAY THE DRIER NW FLOW WILL BRING A RETURN TO A MUCH
DRIER AIR MASS AND NEAR NORMAL TEMPERATURES. LATE IN THE WEEK AN
UPPER LONGWAVE TROUGH WILL BE CARVED OUT OVER THE GREAT LAKES THAT
WILL GRADUALLY DEEPEN AND SPREAD A MOIST UNSTABLE SW FLOW ALOFT
INTO THE REGION WHILE IN THE LOW LEVELS A MOIST COOL SE FLOW
STRENGTHENS. FRIDAY/SATURDAY THIS UPPER TROUGH WILL REMAIN TO OUR
WEST BUT SEVERAL WEAK COASTAL LOWS MAY TRY TO DEVELOP AND POSSIBLY
SPREAD STEADIER RAINS ACROSS THE AREA. QPF AMOUNTS WILL BECOME
DEPENDENT ON THE PRECISE EVOLUTION OF THIS BROAD COMPLEX SYSTEM
LATE IN THE WEEK. ALL MODELS ARE HINTING AT THIS BUT WITH SOME
DIFFERENCES IN TIMING AND SCENARIOS. LATE IN THE WEEK TEMPERATURES
WILL BE QUITE COOL AS THE MOIST DAMP SE FLOW DEVELOPS.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...
GENERALLY VFR CONDITIONS TO START THE DAY. CEILINGS/VISIBILITIES
BEGIN TO LOWER DURING THE EARLY AFTERNOON HOURS IN THE MOUNTAINS
AS SHOWERS AND THUNDERSTORMS DEVELOP AHEAD OF AN APPROACHING COLD
FRONT. EXPECT IFR CONDITIONS WITH LOCALLY LIFR IN ANY SHOWERS
AND STORMS AS THEY GRADUALLY EXIT THE MOUNTAINS AND MOVE TOWARDS
THE COASTLINE BY LATER IN THE DAY. SCATTERED SHOWERS AND STORMS
WILL CONTINUE TONIGHT...AND ALSO MONDAY MORNING OVER FAR SOUTHERN
SECTIONS.
LONG TERM...
VFR CONDITIONS TUESDAY/WEDNESDAY BECOMING MVFR IN DEVELOPING
SCATTERED SHOWERS BY LATE THURSDAY.
&&
.MARINE...
SHORT TERM...
EXPECT WINDS TO STRENGTHEN TODAY AHEAD OF THE COLD FRONT WITH
WAVE HEIGHTS INCREASING AS WELL. SCA CONTINUES THRU LATE TONIGHT...BUT
WINDS SHOULD STAY BELOW GALE CRITERIA. SCAS EXPANDED TO INCLUDE
THE BAYS AS WAVES WILL BE INCREASING AS WELL.
LONG TERM...
WINDS AND SEAS TO REMAIN BELOW SCA CONDITIONS.
&&
.FIRE WEATHER...
INCREASING MOISTURE ACROSS THE AREA WILL KEEP RELATIVE HUMIDITY
VALUES UP THE NEXT FEW DAYS. THUNDERSTORMS WILL POSE A RISK OF
LIGHTNING BUT WILL ALSO BE PROVIDING SUBSTANTIAL RAINFALL TO AREAS
WHICH ARE AFFECTED BY THEM.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT MONDAY FOR ANZ150>154.
&&
$$
NEAR TERM UPDATE... KIMBLE
AREA FORECAST DISCUSSION
NWS GRAY ME
1103 AM EDT SUN JUN 2 2013
.SYNOPSIS...
HIGH PRESSURE SHIFTS EAST TODAY WITH A COLD FRONT APPROACHING
FROM THE WEST. EXPECT SHOWERS AND THUNDERSTORMS TO DEVELOP TODAY
AHEAD OF THE FRONT WITH THE POTENTIAL TO PRODUCE STRONG WINDS AND
HEAVY RAIN. THE FRONT IS SLOW TO PUSH THROUGH THE AREA AND THERE
WILL BE A THREAT FOR MORE SHOWERS AND THUNDERSTORMS NEAR THE COAST
ON MONDAY. HIGH PRESSURE WILL BUILD SOUTHEAST OUT OF CANADA
THROUGH THE MIDDLE OF THE WEEK...BRINGING COOLER WEATHER BACK INTO
THE AREA.
&&
.NEAR TERM /TODAY/...
11AM UPDATE... MADE FURTHER ADJUSTMENTS TO HOURLY POP FORECAST TO
SHOW PROGRESSION OF PRECIPITATION CHANCES ACROSS THE AREA. LINE OF
STORMS HAS FORMED IN VERMONT AND IS MOVING INTO NEW HAMPSHIRE NOW.
OTHER CUMULUS HAS DEVELOPED OVER THE MOUNTAINS OF WESTERN MAINE
WHICH MAY LEAD TO THUNDERSTORM DEVELOPMENT AS WELL. SEVERE
THUNDERSTORM WATCH MAY BE NEEDED BY THIS AFTERNOON.
815AM UPDATE... HAVE MADE ADJUSTMENTS MAINLY TO HOURLY POP GRIDS
TO REFLECT THAT RAIN IS NOT EXPECTED NOW BUT CHANCES INCREASE
AFTER ABOUT 11AM. STILL EXPECTING SHOWERS AND THUNDERSTORMS TO
FORM ACROSS NEW HAMPSHIRE AND NORTHWEST MAINE LATE THIS MORNING OR
EARLY THIS AFTERNOON... WITH A LINE FORMING AND MOVING ACROSS THE
AREA THIS EVENING. STILL A THREAT FOR DAMAGING WINDS PRIMARILY.
7AM UPDATE... HAVE UPDATED GRIDS BASED ON CURRENT CONDITIONS
ACROSS MAINE/NEW HAMPSHIRE. BANDS OF SHOWERS AND STORMS THAT WERE
LOCATED ACROSS THE MOUNTAINS HAS WEAKENED AND SHIFTED NORTH.
MEANWHILE...A LARGE AREA OF PRECIPITATION WITH EMBEDDED CONVECTION
IS MOVING NORTHEAST INTO UPSTATE NEW YORK.
TIMING OF PRECIPITATION MAY NEED TO BE NUDGED FORWARD IN TIME A
COUPLE HOURS...HOWEVER LATEST HRRR RUN CONTINUES TO SHOW THE
CONVECTION REACHING THE MOUNTAINS OF MAINE AND WESTERN NEW
HAMPSHIRE BETWEEN 19Z- 20Z.
HAVE ADJUSTED CLOUDS BASED ON SATELLITE IMAGERY...DEW POINTS AND
TEMPERATURES THIS PACKAGE.
ORIGINAL DISCUSSION... A SLIGHT RISK FOR SEVERE THUNDERSTORMS
CONTINUES TODAY INTO THIS EVENING.
CONVECTION WILL REDEVELOP TODAY AHEAD OF AN APPROACHING COLD FRONT
AND PRE FRONTAL SURFACE TROUGH. STRONG WIND FIELDS WILL ALLOW FOR THE
POSSIBILITY OF DAMAGING WINDS...MAINLY IN BOWING OR LEWP SEGMENTS.
CANNOT RULE OUT THE POSSIBILITY OF HAIL IN ANY DISCRETE STORMS.
MID LEVEL LAPSE RATES DECREASE DURING THE DAY...AND WITH GOOD SOLAR
HEATING OVER SOUTHERN INTERIOR SECTIONS...CAPE VALUES WILL CLIMB
TO AT OR ABOVE 1000 J/KG...WITH A FEW FAR SOUTHERN INTERIOR AREAS
APPROACHING 2000 J/KG.
LOW LEVEL HELICITY VALUES WILL INCREASE DURING THE DAY AS WELL WHICH
MAY LEAD TO ISOLATED SUPERCELLS.
STORM MOTION WILL BE RELATIVELY RAPID...BUT WITH THE FRONT SLOWLY
OVER THE REGION...TRAINING ECHOES MAY LEAD TO LOCALLY HEAVY RAINFALL.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
THUNDERSTORMS WILL BE CONTINUING INTO TONIGHT AS SURFACE COLD
FRONT CONTINUES TO SLOW IN ITS FORWARD MOTION. FAR SOUTHERN
AREAS MAY HAVE YET ANOTHER ROUND OF SHOWERS AND STORMS MONDAY
MORNING AS MODELS CONTINUE TO SHOW A WEAKNESS IN THE SURFACE
FIELDS AND POSSIBLY THE DEVELOPMENT OF A WAVE OF LOW PRESSURE IN
THE GULF OF MAINE.
THE PRECIPITATION WILL ALLOW FOR A MOIST GROUND AND MORE PATCHY
FOG TO DEVELOP TONIGHT. USED OF A BLEND OF MAV/MET MOS FOR
OVERNIGHT MINS AND DAYTIME HIGHS ON MONDAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
THE COLD FRONT MOVES OFF THE COAST BY MONDAY EVENING ALLOWING
CLEARING BEHIND THE FRONT ON A DEVELOPING WNW DOWNSLOPING FLOW.
TUESDAY/WEDNESDAY THE DRIER NW FLOW WILL BRING A RETURN TO A MUCH
DRIER AIR MASS AND NEAR NORMAL TEMPERATURES. LATE IN THE WEEK AN
UPPER LONGWAVE TROUGH WILL BE CARVED OUT OVER THE GREAT LAKES THAT
WILL GRADUALLY DEEPEN AND SPREAD A MOIST UNSTABLE SW FLOW ALOFT
INTO THE REGION WHILE IN THE LOW LEVELS A MOIST COOL SE FLOW
STRENGTHENS. FRIDAY/SATURDAY THIS UPPER TROUGH WILL REMAIN TO OUR
WEST BUT SEVERAL WEAK COASTAL LOWS MAY TRY TO DEVELOP AND POSSIBLY
SPREAD STEADIER RAINS ACROSS THE AREA. QPF AMOUNTS WILL BECOME
DEPENDENT ON THE PRECISE EVOLUTION OF THIS BROAD COMPLEX SYSTEM
LATE IN THE WEEK. ALL MODELS ARE HINTING AT THIS BUT WITH SOME
DIFFERENCES IN TIMING AND SCENARIOS. LATE IN THE WEEK TEMPERATURES
WILL BE QUITE COOL AS THE MOIST DAMP SE FLOW DEVELOPS.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...
GENERALLY VFR CONDITIONS TO START THE DAY. CEILINGS/VISIBILITIES
BEGIN TO LOWER DURING THE EARLY AFTERNOON HOURS IN THE MOUNTAINS
AS SHOWERS AND THUNDERSTORMS DEVELOP AHEAD OF AN APPROACHING COLD
FRONT. EXPECT IFR CONDITIONS WITH LOCALLY LIFR IN ANY SHOWERS
AND STORMS AS THEY GRADUALLY EXIT THE MOUNTAINS AND MOVE TOWARDS
THE COASTLINE BY LATER IN THE DAY. SCATTERED SHOWERS AND STORMS
WILL CONTINUE TONIGHT...AND ALSO MONDAY MORNING OVER FAR SOUTHERN
SECTIONS.
LONG TERM...
VFR CONDITIONS TUESDAY/WEDNESDAY BECOMING MVFR IN DEVELOPING
SCATTERED SHOWERS BY LATE THURSDAY.
&&
.MARINE...
SHORT TERM...
EXPECT WINDS TO STRENGTHEN TODAY AHEAD OF THE COLD FRONT WITH
WAVE HEIGHTS INCREASING AS WELL. SCA CONTINUES THRU LATE TONIGHT...BUT
WINDS SHOULD STAY BELOW GALE CRITERIA. SCAS EXPANDED TO INCLUDE
THE BAYS AS WAVES WILL BE INCREASING AS WELL.
LONG TERM...
WINDS AND SEAS TO REMAIN BELOW SCA CONDITIONS.
&&
.FIRE WEATHER...
INCREASING MOISTURE ACROSS THE AREA WILL KEEP RELATIVE HUMIDITY
VALUES UP THE NEXT FEW DAYS. THUNDERSTORMS WILL POSE A RISK OF
LIGHTNING BUT WILL ALSO BE PROVIDING SUBSTANTIAL RAINFALL TO AREAS
WHICH ARE AFFECTED BY THEM.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT MONDAY FOR ANZ150>154.
&&
$$
NEAR TERM UPDATE... KIMBLE
AREA FORECAST DISCUSSION
NWS GRAY ME
817 AM EDT SUN JUN 2 2013
.SYNOPSIS...
HIGH PRESSURE SHIFTS EAST TODAY WITH A COLD FRONT APPROACHING
FROM THE WEST. EXPECT SHOWERS AND THUNDERSTORMS TO DEVELOP TODAY
AHEAD OF THE FRONT WITH THE POTENTIAL TO PRODUCE STRONG WINDS AND
HEAVY RAIN. THE FRONT IS SLOW TO PUSH THROUGH THE AREA AND THERE
WILL BE A THREAT FOR MORE SHOWERS AND THUNDERSTORMS NEAR THE COAST
ON MONDAY. HIGH PRESSURE WILL BUILD SOUTHEAST OUT OF CANADA
THROUGH THE MIDDLE OF THE WEEK...BRINGING COOLER WEATHER BACK INTO
THE AREA.
&&
.NEAR TERM /TODAY/...
815AM UPDATE... HAVE MADE ADJUSTMENTS MAINLY TO HOURLY POP GRIDS
TO REFLECT THAT RAIN IS NOT EXPECTED NOW BUT CHANCES INCREASE
AFTER ABOUT 11AM. STILL EXPECTING SHOWERS AND THUNDERSTORMS TO
FORM ACROSS NEW HAMPSHIRE AND NORTHWEST MAINE LATE THIS MORNING OR
EARLY THIS AFTERNOON... WITH A LINE FORMING AND MOVING ACROSS THE
AREA THIS EVENING. STILL A THREAT FOR DAMAGING WINDS PRIMARILY.
7AM UPDATE... HAVE UPDATED GRIDS BASED ON CURRENT CONDITIONS
ACROSS MAINE/NEW HAMPSHIRE. BANDS OF SHOWERS AND STORMS THAT WERE
LOCATED ACROSS THE MOUNTAINS HAS WEAKENED AND SHIFTED NORTH.
MEANWHILE...A LARGE AREA OF PRECIPITATION WITH EMBEDDED CONVECTION
IS MOVING NORTHEAST INTO UPSTATE NEW YORK.
TIMING OF PRECIPITATION MAY NEED TO BE NUDGED FORWARD IN TIME A
COUPLE HOURS...HOWEVER LATEST HRRR RUN CONTINUES TO SHOW THE
CONVECTION REACHING THE MOUNTAINS OF MAINE AND WESTERN NEW
HAMPSHIRE BETWEEN 19Z- 20Z.
HAVE ADJUSTED CLOUDS BASED ON SATELLITE IMAGERY...DEW POINTS AND
TEMPERATURES THIS PACKAGE.
ORIGINAL DISCUSSION... A SLIGHT RISK FOR SEVERE THUNDERSTORMS
CONTINUES TODAY INTO THIS EVENING.
CONVECTION WILL REDEVELOP TODAY AHEAD OF AN APPROACHING COLD FRONT
AND PRE FRONTAL SURFACE TROUGH. STRONG WIND FIELDS WILL ALLOW FOR THE
POSSIBILITY OF DAMAGING WINDS...MAINLY IN BOWING OR LEWP SEGMENTS.
CANNOT RULE OUT THE POSSIBILITY OF HAIL IN ANY DISCRETE STORMS.
MID LEVEL LAPSE RATES DECREASE DURING THE DAY...AND WITH GOOD SOLAR
HEATING OVER SOUTHERN INTERIOR SECTIONS...CAPE VALUES WILL CLIMB
TO AT OR ABOVE 1000 J/KG...WITH A FEW FAR SOUTHERN INTERIOR AREAS
APPROACHING 2000 J/KG.
LOW LEVEL HELICITY VALUES WILL INCREASE DURING THE DAY AS WELL WHICH
MAY LEAD TO ISOLATED SUPERCELLS.
STORM MOTION WILL BE RELATIVELY RAPID...BUT WITH THE FRONT SLOWLY
OVER THE REGION...TRAINING ECHOES MAY LEAD TO LOCALLY HEAVY RAINFALL.
&&
.SHORT TERM /TONIGHT AND MONDAY/...
THUNDERSTORMS WILL BE CONTINUING INTO TONIGHT AS SURFACE COLD
FRONT CONTINUES TO SLOW IN ITS FORWARD MOTION. FAR SOUTHERN
AREAS MAY HAVE YET ANOTHER ROUND OF SHOWERS AND STORMS MONDAY
MORNING AS MODELS CONTINUE TO SHOW A WEAKNESS IN THE SURFACE
FIELDS AND POSSIBLY THE DEVELOPMENT OF A WAVE OF LOW PRESSURE IN
THE GULF OF MAINE.
THE PRECIPITATION WILL ALLOW FOR A MOIST GROUND AND MORE PATCHY
FOG TO DEVELOP TONIGHT. USED OF A BLEND OF MAV/MET MOS FOR
OVERNIGHT MINS AND DAYTIME HIGHS ON MONDAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
THE COLD FRONT MOVES OFF THE COAST BY MONDAY EVENING ALLOWING
CLEARING BEHIND THE FRONT ON A DEVELOPING WNW DOWNSLOPING FLOW.
TUESDAY/WEDNESDAY THE DRIER NW FLOW WILL BRING A RETURN TO A MUCH
DRIER AIR MASS AND NEAR NORMAL TEMPERATURES. LATE IN THE WEEK AN
UPPER LONGWAVE TROUGH WILL BE CARVED OUT OVER THE GREAT LAKES THAT
WILL GRADUALLY DEEPEN AND SPREAD A MOIST UNSTABLE SW FLOW ALOFT
INTO THE REGION WHILE IN THE LOW LEVELS A MOIST COOL SE FLOW
STRENGTHENS. FRIDAY/SATURDAY THIS UPPER TROUGH WILL REMAIN TO OUR
WEST BUT SEVERAL WEAK COASTAL LOWS MAY TRY TO DEVELOP AND POSSIBLY
SPREAD STEADIER RAINS ACROSS THE AREA. QPF AMOUNTS WILL BECOME
DEPENDENT ON THE PRECISE EVOLUTION OF THIS BROAD COMPLEX SYSTEM
LATE IN THE WEEK. ALL MODELS ARE HINTING AT THIS BUT WITH SOME
DIFFERENCES IN TIMING AND SCENARIOS. LATE IN THE WEEK TEMPERATURES
WILL BE QUITE COOL AS THE MOIST DAMP SE FLOW DEVELOPS.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...
GENERALLY VFR CONDITIONS TO START THE DAY. CEILINGS/VISIBILITIES
BEGIN TO LOWER DURING THE EARLY AFTERNOON HOURS IN THE MOUNTAINS
AS SHOWERS AND THUNDERSTORMS DEVELOP AHEAD OF AN APPROACHING COLD
FRONT. EXPECT IFR CONDITIONS WITH LOCALLY LIFR IN ANY SHOWERS
AND STORMS AS THEY GRADUALLY EXIT THE MOUNTAINS AND MOVE TOWARDS
THE COASTLINE BY LATER IN THE DAY. SCATTERED SHOWERS AND STORMS
WILL CONTINUE TONIGHT...AND ALSO MONDAY MORNING OVER FAR SOUTHERN
SECTIONS.
LONG TERM...
VFR CONDITIONS TUESDAY/WEDNESDAY BECOMING MVFR IN DEVELOPING
SCATTERED SHOWERS BY LATE THURSDAY.
&&
.MARINE...
SHORT TERM...
EXPECT WINDS TO STRENGTHEN TODAY AHEAD OF THE COLD FRONT WITH
WAVE HEIGHTS INCREASING AS WELL. SCA CONTINUES THRU LATE TONIGHT...BUT
WINDS SHOULD STAY BELOW GALE CRITERIA. SCAS EXPANDED TO INCLUDE
THE BAYS AS WAVES WILL BE INCREASING AS WELL.
LONG TERM...
WINDS AND SEAS TO REMAIN BELOW SCA CONDITIONS.
&&
.FIRE WEATHER...
INCREASING MOISTURE ACROSS THE AREA WILL KEEP RELATIVE HUMIDITY
VALUES UP THE NEXT FEW DAYS. THUNDERSTORMS WILL POSE A RISK OF
LIGHTNING BUT WILL ALSO BE PROVIDING SUBSTANTIAL RAINFALL TO AREAS
WHICH ARE AFFECTED BY THEM.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT MONDAY FOR ANZ150>154.
&&
$$
NEAR TERM UPDATE... KIMBLE
AREA FORECAST DISCUSSION
NWS GRAY ME
656 AM EDT SUN JUN 2 2013
.SYNOPSIS...
HIGH PRESSURE SHIFTS EAST TODAY WITH A COLD FRONT APPROACHING
FROM THE WEST. EXPECT SHOWERS AND THUNDERSTORMS TO DEVELOP TODAY
AHEAD OF THE FRONT WITH THE POTENTIAL TO PRODUCE STRONG WINDS AND
HEAVY RAIN. THE FRONT IS SLOW TO PUSH THROUGH THE AREA AND THERE
WILL BE A THREAT FOR MORE SHOWERS AND THUNDERSTORMS NEAR THE COAST
ON MONDAY. HIGH PRESSURE WILL BUILD SOUTHEAST OUT OF CANADA
THROUGH THE MIDDLE OF THE WEEK...BRINGING COOLER WEATHER BACK INTO
THE AREA.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
HAVE UPDATED GRIDS BASED ON CURRENT CONDS ACROSS ME/NH. BANDS OF
SHOWERS AND STORMS THAT WERE LOCATED ACROSS THE MTNS HAS WEAKENED
AND SHIFTED NORTH. MEANWHILE...A LARGE AREA OF PCPN WITH EMBEDDED
CONVECTION IS MOVING NE INTO UPSTATE NEW YORK.
TIMING OF PCPN MAY NEED TO BE NUDGED FORWARD IN TIME A COUPLE
HOURS...HOWEVER LATEST HRRR RUN CONTS TO SHOW THE CONVECTION
REACHING THE MTNS OF ME AND WRNMST NH BTWN 19Z-20Z.
HAVE ADJUSTED CLOUDS BASED ON STLT IMAGERY...DEW POINTS AND TEMPS
THIS PACKAGE.
PREV DISC...
A SLGT RISK FOR SVR TSTMS CONTINUES TODAY INTO THIS EVENING.
CONVECTION WILL REDEVELOP TODAY AHEAD OF AN APCHG COLD FRONT AND
PREFRONTAL SFC TROUGH. STRONG WIND FIELDS WILL ALLOW FOR THE
POSSIBILITY OF DAMAGING WINDS...MAINLY IN BOWING OR LEWP SEGMENTS.
CANNOT RULE OUT THE POSSIBILITY OF HAIL IN ANY DESCRETE STORMS.
MID LEVEL LAPSE RATES INCREASE DURING THE DAY...AND WITH GOOD SOLAR
HEATING OVER SOUTHERN INTERIOR SECTIONS...CAPE VALUES WILL CLIMB
TO AOA 1000 J/KG...WITH A FEW FAR SOUTHERN INTERIOR AREAS APCHG
2000 J/KG.
LOW LEVEL HELICITY VALUES WILL INCREASE DURING THE DAY AS WELL WHICH
MAY LEAD TO ISOLD SUPERCELLS.
STORM MOTION WILL BE RELATIVELY RAPID...BUT WITH THE FRONT SLOWLY
OVER THE REGION...TRAIN ECHOES MAY LEAD TO LOCALLY HEAVY RAINFALL.
&&
.SHORT TERM /MONDAY THROUGH MONDAY NIGHT/...
TSTMS WILL BE CONTINUING INTO TONIGHT AS SFC COLD FRONT CONTS TO
SLOW IN ITS FORWARD MOTION. FAR SOUTHERN AREAS MAY HAVE YET
ANOTHER ROUND OF SHOWERS AND STORMS MONDAY MORNING AS MODELS CONT
TO SHOW A WEAKNESS IN THE SFC FIELDS AND POSSIBLY THE DEVELOPMENT
OF A WAVE OF LOW PRESSURE IN THE GULF OF MAINE.
THE PCPN WILL ALLOW FOR A MOIST GROUND AND MORE PATCHY FOG TO
DEVELOP TONIGHT. USED OF ABLEND OF MAV/MET MOS FOR OVERNIGHT MINS
AND DAYTIME HIGHS ON MONDAY.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
THE COLD FRONT MOVES OFF THE COAST BY MON EVENING ALLOWING
CLEARING BEHIND THE FROPA ON A DEVELOPING WNWLY DOWNSLOPING FLOW.
TUE/WED THE DRIER NWLY FLOW WILL BRING A RETURN TO A MUCH DRIER
AMS AND NEAR NORMAL TEMPS. LATE IN THE WEEK AN UPPER L/WV TROF
WILL BE CARVED OUT OVER THE GREAT LAKES THAT WILL GRADUALLY DEEPEN
AND SPREAD A MOIST UNSTABLE SWLY FLOW ALOFT INTO THE REGION WHILE
IN THE LOW LEVELS A MOIST COOL SELY FLOW STRENGTHENS. FRI/SAT THIS
UPPER TROF WILL REMAIN TO OUR WEST BUT SEVERAL WEAK COASTAL LOWS
MAY TRY TO DEVELOP AND POSSIBLY SPREAD STEADIER RAINS ACROSS THE
AREA. QPF AMTS WILL BECOME DEPENDANT ON THE PRECISE EVOLUTION OF
THIS BROAD COMPLEX SYSTEM LATE IN THE WEEK. ALL MODELS ARE HINTING AT
THIS BUT WITH SOME DIFFERENCES IN TIMING AND SCENARIOS. LATE IN
THE WEEK TEMPS WILL BE QUITE COOL AS THE MOIST DAMP SELY FLOW
DEVELOPS.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...
PATCHY FOG EXPECTED EARLY THIS MORNING...FOLLOWED BY GENERALLY VFR
CONDITIONS. CIGS/VSBYS BEGIN TO LOWER DURING THE EARLY AFTERNOON
HOURS IN THE MTNS AS SHOWERS AND TSTMS DEVELOP AHEAD OF AN APCHG
COLD FRONT. EXPECT IFR CONDITIONS WITH LOCALLY LIFR IN ANY SHOWERS
AND STORMS AS THEY GRADUALLY EXIT THE MTNS AND MOVE TOWARDS THE
COASTLINE BY LATER IN THE DAY. SCT SHOWERS AND STMS WILL CONT
TNGT...AND ALSO MONDAY MORNING OVER FAR SOUTHERN SECTIONS.
LONG TERM...
VFR CONDS TUE/WED BECOMING MVFR IN DVLP SCT SHWRS BY LATE THU.
&&
.MARINE...
SHORT TERM...
EXPECT WINDS TO STRENGTHEN TODAY AHEAD OF THE COLD FRONT WITH
WAVE HEIGHTS INCREASING AS WELL. SCA CONTINUES THRU LATE TONIGHT...BUT
WINDS SHOULD STAY BELOW GALE CRITERIA. SCAS EXPANDED TO INCLUDE
THE BAYS AS WAVES WILL BE INCREASING AS WELL.
LONG TERM...
WINDS AND SEAS TO REMAIN BELOW SCA CONDS.
&&
.FIRE WEATHER...
INCREASING MOISTURE ACROSS THE AREA WILL KEEP RELATIVE HUMIDITY
VALUES UP THE NEXT FEW DAYS. THUNDERSTORMS WILL POSE A RISK OF
LIGHTNING BUT WILL ALSO BE PROVIDING SUBSTANTIAL RAINFALL TO AREAS
WHICH ARE AFFECTED BY THEM.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT MONDAY FOR ANZ150>154.
&&
$$
JC
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1032 AM EDT SUN JUN 2 2013
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE WEST TODAY...THEN PASS THROUGH
THE AREA TONIGHT AND MONDAY. CANADIAN HIGH PRESSURE WILL BUILD IN
BEHIND THE FRONT THROUGH MIDWEEK. ANOTHER FRONT MAY APPROACH THE
MIDDLE ATLANTIC STATES AT THE END OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
VSBLE SATL IMGRY AND SFC OBS SHOW EXTENSIVE CLOUD COVER OVER THE
WESTERN HALF OF CWA. TEMPS ARE ALREADY IN THE LOW 80S IN THE MOSTLY
SUNNY SKIES ALONG AND EAST OF I-95.
MODIFIED 12Z KIAD SOUNDING GIVES ML CAPES IN THE VICINITY OF
1250-1500 J/KG. THE RR QUAD OF H4 JET WILL MOVE ACROSS THE THE NW
PORTION OF CWA THIS AFTERNOON PROVIDING A LIFTING MECHANISM TO
PRODUCE SHOWERS AND THUNDERSTORMS. THE THREAT FOR SVR WX EXISTS
THIS AFTERNOON AND EVENING COINCIDING WITH PEAK INSOLATION.
HAVED NUDGED TEMPS WEST OF THE BLUE RIDGE DOWN A COUPLE OF DEGREES
DUE TO BKN-OVC.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
COLD FRONT ENTERS THE CWA TONIGHT. MODELS NOT YET CONSISTENT ON ITS
EASTWARD PROGRESS BY MONDAY MORNING...WITH GFS HAVING THE FRONT
THROUGH MOST OF THE AREA...ECMWF (12Z SUN) THE SLOWEST...AND THE
NAM IN BETWEEN. WILL CONTINUE WITH POTENTIAL FOR SHOWERS AND TSTMS
OVERNIGHT...WITH HIGHEST POPS EAST OF I-95 CORRIDOR. LOW TEMPS
RANGE FROM THE LOW 60S OVER THE POTOMAC HIGHLANDS TO THE LOW 70S
IN URBAN BALTIMORE/WASHINGTON.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
COLD FRONT WILL BE MOVING THROUGH THE POTOMAC HIGHLANDS BY MONDAY
MORNING. SHOWERS AND ISOLATED THUNDERSTORMS ARE POSSIBLE AHEAD OF
FROPA FOR AREAS ALONG AND EAST OF THE I-95 CORRIDOR THROUGHOUT THE
MORNING AND AFTERNOON. FURTHER SOUTH AND EAST...LOW LEVEL JET WILL
BECOME MORE PERPENDICULAR TO THE STORM MOTION AND HELP LEVITATE
HEAVY RAIN THAT WE MAY SEE SUNDAY EVENING. FCST SOUNDINGS WILL
STILL BE SATURATED WITH PWATS AT OR ABOVE 1.5 SO ISOLATED AREAS OF
HEAVY RAIN WILL STILL POSE A THREAT FOR SOUTHERN MARYLAND MONDAY
AFTERNOON WITHIN THUNDERSTORM ACTIVITY.
HIGH PRESSURE AND NW FLOW BEHIND FROPA WILL DROP DEWPTS AS IT MOVES
THROUGH THE MID ATLANTIC MONDAY NIGHT. CONTINENTAL AIR WILL BRING RELIEF
OF RECENT WARM SPELL FOR THE START OF NEXT WEEK WITH HIGH
TEMPERATURES NEAR OR SLIGHTLY BELOW NORMAL.
E-SE FLOW WILL BEGIN TUESDAY NIGHT AND USHER IN LOW LEVEL MOISTURE
INTO THE MID ATLANTIC AS HIGH PRESSURE MOVES OFF SHORE. LOW
PRESSURE FROM THE OHIO VALLEY WILL FORM ALONG A COLD FRONT AND MOVE
TOWARDS THE REGION BY THE END OF THE WEEK. REGION SHOULD STAY DRY
UNTIL THURSDAY NIGHT WHEN SHOWERS WILL OVERSPREAD THE AREA AS A
UPPER TROUGH MOVES CLOSER. MULTIPLE SHORTWAVE TROUGHS AND LOW
PRESSURE OFF THE ATLANTIC COAST MAY LEAD TO CLOUDY AND WET
CONDITIONS TOWARDS THE END OF THE WEEK AND START OF THE WEEKEND.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL DEVELOP
THIS AFTERNOON AND EVENING AND WILL LIKELY BRING IMPACTS TO THE
TERMINALS. STORMS WILL HAVE THE POTENTIAL TO PRODUCE DAMAGING
WINDS...HAIL AND HEAVY RAINFALL. AMENDMENTS MAY BE NECESSARY TO
REFINE TIMING AND IMPACT OF SHOWERS/TSTMS. WINDS GENERALLY SW
10-15KT...POSSIBLY GUSTY AT TIMES.
VFR CONDITIONS EXPECTED FOR THE START OF THE WORK WEEK WITH THE
EXCEPTION OF SOME ONGOING SHOWERS AT IAD-DCA-BWI-MTN MONDAY. WINDS WILL
SHIFT FROM THE SW TO THE NW BY MONDAY EVENING ACROSS ALL TERMINALS.
&&
.MARINE...
PRESSURE GRADIENT ON 00Z MODEL RUN IS A LITTLE LESS THAN PREVIOUS
RUNS...AND WIND DIRECTION IS EXPECTED TO BE MORE SWLY THAN
SOUTHERLY...WHICH WOULD INHIBIT CHANNELING. AS SUCH...SCA
CONDITIONS WILL LIKELY BE SOMEWHAT MARGINAL...BUT WILL KEEP THE
ADVISORY IN PLACE.
SHOWERS AND THUNDERSTORMS LATE THIS AFTERNOON AND EARLY EVENING
HAVE THE POTENTIAL TO PRODUCE STRONG WIND GUSTS...HEAVY RAIN AND
HAIL.
SHOWERS AND ISOLATED THUNDERSTORMS WILL BE ONGOING INTO THE START OF
THE WORK WEEK. WINDS WILL SHIFT FROM THE SW TO THE NW BY MONDAY
EVENING AS A COLD FRONT CROSSES.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
ANZ530>543.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
738 AM EDT SUN JUN 2 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 520 AM EDT SUN JUN 2 2013
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM
NW ONTARIO INTO THE CNTRL GREAT LAKES. A SHORTWAVE SUPPORTING OVER
NRN LAKE MICHIGAN INTO NW LOWER MI SUPPORTED AN AREA OF RAIN OVER
ERN UPPER MI THAT WAS SLOWLY SLIDING OFF TO THE EAST. SCT LIGHT
SHOWERS ALSO LINGERED OVER CNTRL UPPER MI. AT THE SFC...A TIGHT
GRADIENT BETWEEN LOW PRES OVER LAKE HURON AND A RIDGE INTO THE NRN
PLAINS SUPPORTED BRISK NRLY WINDS ACROSS LAKE SUPERIOR INTO THE
UPPER MI. UPSLOPE NRLY FLOW INTO THE HIGHER TERRAIN ALSO SUPPORTED
AREAS OF DRIZZLE. MUCH COLDER AIR HAS MOVED INTO THE REGION WITH
TEMPS DROPPING INTO THE UPPER 30S AND LOWER 40S.
TODAY...ALTHOUGH THE NAM AND HIGH RES MODELS SHOW LOW LEVEL
DRYING WILL SPREAD THROUGH MOST OF THE CWA THIS MORNING...UPSTREAM
CLOUDS TRENDS SUGGEST THAT THE CLEARING TREND MAY BE SLOWER. ANY
LINGERING LIGHT SHOWERS OR DRIZZLE SHOULD END BY MID OR LATE MORNING
WITH CLEARING FROM WEST TO EAST BY EARLY TO MID AFTERNOON. EVEN WITH
SUNSHINE...WITH N FLOW ACROSS LAKE SUPERIOR AND 850 MB TEMPS NEAR
-1C...TEMPS WILL STRUGGLE INTO THE UPPER 40S TO LOWER 50S NORTH AND
INTO THE MID AND UPPER 50S SOUTH.
TONIGHT...SFC HIGH PRES BUILDING INTO THE REGION FROM THE WEST
SUNDAY NIGHT WILL RESULT IN IDEAL RADIATIONAL COOLING CONDITIONS
OVER THE WESTERN INTERIOR OF THE CWA WHERE MIN TEMPS WILL LIKELY
FALL INTO LOWER 30S...NEAR THE LOWER END OF GUIDANCE.
SOME TRADITIONAL COLD SPOTS COULD ALSO SEE READINGS INTO THE UPPER
20S. SO...A FROST ADVISORY WAS ISSUED FOR INLAND PORTIONS OF THE WEST
HALF OF UPPER MICHIGAN. A VORTEX DESCENDING FROM NRN ONTARIO IS
EXPECTED TO GRAZE NE LAKE SUPERIOR. ALTHOUGH PCPN AND CLOUDS WITH
THIS FEATURE ARE EXPECTED TO REMAIN THE NE OF THE CWA...THE VORTEX
WILL RESULT IN NW WINDS STRONG ENOUGH TO MAINTAIN SOME BOUNDARY LAYER
MIXING AND PREVENT TEMPS FROM DROPPING OFF AS FAR AS IN THE WEST.
LOOK FOR MAINLY MID TO UPPER 30S MIN TEMPS OVER THE EAST HALF.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 343 AM EDT SUN JUN 2 2013
UPPER TROUGH THAT IS CURRENTLY AFFECTING THE UPPER GREAT LAKES
EARLY THIS MORNING WILL BE SHIFTING EAST THROUGH EASTERN CANADA ON
MONDAY. THIS WILL LEAD TO THE AREA BEING UNDER NORTHWEST FLOW ALOFT
AND A SURFACE HIGH PRESSURE RIDGE FROM A HIGH CENTERED IN SOUTH
CENTRAL CANADA. WITH DRY LOW AND MID LEVELS UNDER THE HIGH PRESSURE
RIDGE...EXPECT A MOSTLY SUNNY SKY ACROSS MUCH OF THE LAND AREA.
THERE COULD BE SOME LINGERING CLOUDS OVER NORTHEAST LAKE SUPERIOR
AND FAR EASTERN UPPER MICHIGAN AS THE UPPER TROUGH DEPARTS. WITH
THE SUNSHINE...EXPECT MIXING TO AROUND 850-825MB. BUT WITH
TEMPERATURES AT THAT LEVEL ONLY AROUND 2C WEST AND -1C EAST...BELOW
NORMAL HIGHS ARE EXPECTED AND ONLY IN THE 50S AND LOWER 60S. THE
COOLEST TEMPERATURES WILL BE ALONG THE GREAT LAKES SHORELINES DUE
TO LAKE BREEZES. THE OTHER ITEM TO MENTION FOR MONDAY WILL BE LOW
RH VALUES. ML DEWPOINTS FROM THE MODELS INDICATE VALUES IN THE MID
20S OVER THE INTERIOR LOCATIONS AND POTENTIALLY THE UPPER TEENS IF
THE GFS IS CORRECT. WITH THAT CONSISTENCY AND THE TRENDS IN THE
MAV/MET...HAVE LOWERED OUR DEWPOINTS A GOOD 5-7 DEGREES. THIS
PRODUCES RH VALUES OF 25-35 PERCENT OVER THE INLAND AREAS...WITH
THE LOWEST VALUES OVER THE WEST. FORTUNATELY...THE WET WEATHER
RECENTLY...GREEN UP WELL ON IT/S WAY OR EVEN DONE...AND BELOW NORMAL
TEMPERATURES REDUCES FIRE WEATHER CONCERNS EVEN WITH 10-15KT WINDS.
THE HIGH PRESSURE RIDGE WILL STILL BE OVER THE AREA ON MONDAY NIGHT
AS AN UPPER RIDGE SLIDES ACROSS THE AREA. THE CLEAR SKIES...LIGHT
WINDS...AND PWAT VALUES AROUND 30-40 PERCENT OF NORMAL WILL LEAD TO
A COLD NIGHT ACROSS THE AREA. WILL CONTINUE THE TREND OF GOING
BELOW GUIDANCE VALUES AND HAVE LOWS AROUND 30 OVER THE INTERIOR
LOCATIONS. RECORD LOWS FOR JUNE 4 ARE IN THE MID-UPPER 20S...SO
WE WILL BE CLOSE BUT LIKELY STAY ABOVE THE RECORD LOWS. WILL ALSO
CONTINUE THE MENTION OF FROST FOR MONDAY NIGHT ALONG WITH
HIGHLIGHTING IN HWO.
AREA WILL STILL BE UNDER THE INFLUENCE OF THE HIGH ON TUESDAY...AS
IT DRIFTS SOUTHEAST ACROSS THE CWA THROUGH THE DAY. THIS WILL LEAD
TO LIGHTER WINDS ACROSS THE AREA. DO EXPECT TO SEE SOME HIGH
CLOUDS STREAMING EAST ACROSS THE WESTERN CWA DURING THE
AFTERNOON AHEAD OF THE NEXT SYSTEM APPROACHING THE AREA. HIGHS WILL
BE A LITTLE WARMER ON TUESDAY...AS 850MB TEMPS WARM A COUPLE DEGREES
FROM MONDAY. WITH THE RIDGE LINGERING OVER THE EAST...HAVE LOWERED
TD VALUES SIGNIFICANTLY OVER THE EAST HALF. THIS WILL LIKELY LEAD TO
ANOTHER LOW RH DAY...BUT AS WITH MONDAY...FIRE WX CONCERNS ARE
LIMITED WITH EVEN LIGHTER WINDS.
THE UPPER TROUGH CURRENTLY OVER BRITISH COLUMBIA WILL BE MOVING
THROUGH THE NORTHERN PLAINS ON TUESDAY AND THEN BECOME CLOSE ENOUGH
TO START INFLUENCING THE UPPER GREAT LAKES FOR TUESDAY NIGHT AND
CONTINUING INTO THURSDAY. THERE ARE STILL QUESTIONS ON THE EXACT
TRACK OF THE SHORTWAVE TROUGH...WHICH IN TURN AFFECTS THE LOCATION
OF THE SURFACE LOW AND RESULTANT WARM AIR ADVECTION PRECIPITATION.
LATEST IDEA FROM THE GFS/ECMWF IS THAT MUCH OF THE INITIAL
PRECIPITATION WILL BE WEST OF THE AREA TUESDAY EVENING AND THEN
SLIDE OVER THE AREA TUESDAY NIGHT AND CONTINUE INTO WEDNESDAY NIGHT
AS THE SURFACE LOW/TROUGH SLIDES FROM THE DAKOTAS INTO SOUTHWEST
WISCONSIN. THE WARM AIR ADVECTION IS FAIRLY BROAD AND WEAK...SO
WOULD EXPECT THE PRECIPITATION TO BE GENERAL LIGHT SHOWERS. WITH
THE BEST FORCING FOCUSED OVER WISCONSIN AND THE SOUTHERN HALF OF THE
CWA...HAVE THE HIGHEST POPS IN THAT AREA. SINCE THE BULK OF THE
FORCING IS SOUTH OF THE AREA...WILL KEEP POPS IN THE HIGH CHANCE
CATEGORY SINCE IT IS ENTIRELY POSSIBLE MUCH OF THE RAIN STAYS IN
WISCONSIN. THUNDER CHANCES ARE LIMITED TO NON-EXISTANT...AS
SHOWALTER VALUES ARE WELL ABOVE ZERO AND MUCAPE VALUES STAY BELOW
100 J/KG DURING THIS PERIOD.
EXPECT A DIMINISHING TREND IN THE PRECIPITATION FOR THURSDAY INTO
THURSDAY NIGHT...AS THE DISTURBANCE SHIFTS EAST AND HIGH PRESSURE
NEAR HUDSON BAY PUSHES DRIER AIR INTO THE AREA. THIS SHOULD LEAD TO
DRY WEATHER FOR FRIDAY...BUT ANOTHER WEAK SHORTWAVE TRIES TO SLIDE
EAST ACROSS THE AREA FOR SATURDAY. WITH THE DRY EASTERLY FLOW AND
THE POTENTIAL THE HIGH REMAINS IN PLACE...IT/S ARRIVAL MAY BE
DELAYED SOME. TEMPERATURES FROM MID WEEK ON WILL CONTINUE THE BELOW
NORMAL TREND...WITH HIGHS GENERALLY IN THE 50S-60S AND THE COOLEST
DAY ON WEDNESDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 738 AM EDT SUN JUN 2 2013
EXPECT IFR CONDITIONS ASSOCIATED WITH AN INFLUX OF SHALLOW
COOL...MOIST AIR ON THE HEELS OF GUSTY N WINDS TO IMPROVE TO MVFR
NW-SE EARLY THIS MORNING AS DRIER AIR PUSHES INTO THE AREA AHEAD OF
HIGH PRES BUIDLING TOWARD UPPER MICHIGAN. AS THIS HIGH MOVES
OVERHEAD...CONDITIONS WILL IMPROVE TO VFR...AND THE GUSTY WINDS WILL
DIMINISH. HOWEVER...SATELLITE TRENDS SUGGEST THAT THE IMPROVING WILL
BE SLOWER THAN PREVIOUS FCST.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 520 AM EDT SUN JUN 2 2013
LOW PRESSURE OVER GEORGIAN BAY WILL SHIFT ENE INTO QUEBEC BY THIS
AFTERNOON...WHILE A RIDGE OF HIGH PRESSURE BUILDS OVER NORTHERN
ONTARIO. AS A RESULT...NORTH WINDS WILL DIMINISH TODAY. RIDGING WILL
EXTEND OVER LAKE SUPERIOR TONIGHT...WHICH WILL REMAIN THROUGH MUCH
WEDNESDAY AS THE NEXT LOW WILL SLIDES ACROSS THE NORTHERN PLAINS.
THE LOW WILL SHIFT SLOWLY E INTO THE MID MS VALLEY THURSDAY...WHILE
THE WEAK RIDGE OF HIGH PRESSURE LINGERS OVER LAKE SUPERIOR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
FROST ADVISORY FROM 2 AM EDT /1 AM CDT/ TO 8 AM EDT /7 AM CDT/
MONDAY FOR MIZ002-004-005-009>011-084.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
622 AM CDT SUN JUN 2 2013
.AVIATION...
12Z TAFS FOR KOMA...KLNK AND KOFK.
VFR CONDITIONS EXPECTED THRU THE FCST PD.
DEE
&&
.PREV DISCUSSION... /ISSUED 302 AM CDT SUN JUN 2 2013/
DISCUSSION...
MAIN FORECAST CHALLENGE WAS WHEN TO INCLUDE TSTM CHANCES AS
ANOTHER UPPER TROUGH/LOW MOVES FROM SWRN CANADA ACROSS NORTHERN
PLAINS THROUGH MIDWEEK.
FOR TODAY...UPPER RIDGE AHEAD OF SWRN CANADIAN LOW TO FLATTEN AS
IT BUILDS ACROSS CNTRL PLAINS AS UPPER LOW SOUTH OF HUDSONS BAY
DROPS SOUTH. PERSISTENT LOW CLOUDS HAVE CLEARED WRN ZONES AS OF
730Z AND SHOULD CONTINUE TO DO SO THROUGH THIS MORNING...ALTHOUGH
LATEST RAP SOUNDING DELAYED THIS CLEARING ALONG/E OF MO RIVER TILL
AFTERNOON. SLOWED CLEARING DOWN A BIT E...AND FURTHER ADJUSTMENTS
MAY BE NEEDED. MILDER TEMPS COMPARED TO SATURDAY BUT STILL BELOW
NORMAL AND GENERALLY A DEG OR TWO BELOW GUIDANCE BASED ON PERHAPS
HINDERED MIXING FROM MORNING/EARLY AFTN CLOUDS E AND/OR SLIGHTLY
COOLER H85 TEMPS PER 00Z ECMWF.
UPPER LOW MOVING TOWARD DAKOTAS LATE MONDAY WILL STRENGTHEN LOW
LEVEL JET LATE TONIGHT INTO MONDAY NIGHT. THIS WILL PROVIDE
INCREASING WINDS...ESPECIALLY MONDAY. HOWEVER...WINDS PROBABLY
WILL NOT INCREASE QUICKLY ENOUGH TONIGHT TO HELP LOWS MUCH WITH
GUIDANCE GENERALLY ACCEPTABLE. STORMS THAT DEVELOP TO OUR WEST
LATE TONIGHT AIDED BY THETA E ADVECTION IN LOW LEVEL JET AXIS
COULD MOVE ACROSS SECTIONS OF THE AREA MONDAY MORNING...FOR NOW
CONFINED SLGT CHC POPS TO FAR N. OTHERWISE KEPT MONDAY AFTN DRY.
BOOSTED WIND SPEEDS MONDAY TO JUST BELOW WIND ADVISORY CRITERIA
NWRN ZONES. MAX TEMPERATURES PROBABLY A CATEGORY OR SO WARMER
MOST AREAS LOOKS FINE.
INCREASING POPS MONDAY NIGHT INTO TUESDAY STILL ON TRACK AS UPPER
LOW SHIFTS SE A BIT AND LOW LEVEL JET/CONVERGENCE SHIFTS INTO THE
FORECAST AREA MONDAY NIGHT FOLLOWED BY A COLD FRONT TUESDAY.
ALTHOUGH SOME ADJUSTMENTS WERE MADE AND MORE WILL PROBABLY BE
ADDRESSED IN LATER FORECASTS...IT APPEARS HIGHER POPS WILL BE
SHIFTING TOWARD ERN ZONES THRU LATE TUESDAY. IF CLOUDS/SHOWERS
REMAIN WIDESPREAD TUE MAX TEMPS MAY NEED LOWERING.
CONFIDENCE IS LOW IN HOW SCENARIO TUE NIGHT/WED PLAYS OUT AS A
WAVE ROTATING AROUND UPPER LOW COULD HELP GENERATE MCS TO OUR WSW
IN UPSLOPE REGION ACROSS WRN HIGH PLAINS BY WED AM. SOME OF THIS
ACTIVITY COULD SKIRT AREA WED...SPCLY SOUTH...AND LOW CHC POPS
WERE CARRIED GENERALLY ALONG/S OF HIGHWAY 30. HOWEVER...WE COULD
ALSO SEE JUST MAINLY CLOUDS FROM THIS...BUT EITHER PRECIP OR
CLOUDS COULD IMPACT HIGHS. FOR NOW THEY WERE KEPT IN THE 70S TUE
AND WED.
THURSDAY LOOKED DRY WITH INCREASING TSTM CHANCES AGAIN FROM W TO E
FRIDAY INTO SATURDAY AS NEXT TROUGH APPROACHES. NO CHANGES MADE
FROM MODEL/PREVIOUS FORECAST BLEND.
CHERMOK
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
99/99
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1140 AM EDT SUN JUN 2 2013
.SYNOPSIS...
A COLD FRONT WILL PRODUCE NUMEROUS SHOWERS AND THUNDERSTORMS TODAY
ACROSS THE NORTH COUNTRY. THE STRONGER STORMS WILL BE CAPABLE OF
PRODUCE STRONG AND DAMAGING WINDS...SMALL HAIL...AND LOCALIZED
HEAVY DOWNPOURS. CLEARING AND COOLER TEMPERATURES WILL ARRIVE BY
THE START OF THE WORK WEEK.
&&
.NEAR TERM /UNTIL 11 PM THIS EVENING/...
AS OF 1138 AM EDT SUNDAY...UPDATED ZNS TO REFLECT SVR THUNDERSTORM
WATCH #271 FOR EASTERN DACKS THRU VT UNTIL 8 PM THIS EVENING. REST
OF FCST IN GREAT SHAPE.
UPDATED FCST TO MENTION SHOWERS/STORMS THRU
THIS MORNING FOR CENTRAL/NORTHERN VT AND REMOVED MENTION OF
ENHANCED WORDING THRU THE MORNING HOURS. ALSO...ADJUSTED
TEMPS/DWPTS BASED ON CRNT OBS.
FCST CHALLENGE IS TIMING OF CONVECTION TODAY...FOLLOWED BY AREAL
COVERAGE/INTENSITY OF STORMS THIS AFTN. WATER VAPOR SHOWS POTENT
S/W ENERGY ACRS THE EASTERN GREAT LAKES...WITH ENHANCED RIBBON OF
DEEP LAYER MOISTURE AHEAD OF THIS ENERGY ACRS WESTERN NY/PA. IN
ADDITION...STRONG HGHT FALLS ARE OCCURRING AS MID/UPPER LVL TROF
LIFTS TWD HUDSON`S BAY THIS AFTN AND ASSOCIATED SFC BOUNDARY SWINGS
ACRS OUR CWA.
AT THE SFC...INITIAL PRE-FRNTAL TROF HAS PRODUCED SHOWERS WITH A
FEW EMBEDDED RUMBLES OF THUNDER ACRS THE EASTERN DACKS INTO
NORTHERN/CENTRAL VT THIS MORNING. EXPECT SOME CLRING BEHIND THIS INITIAL
TROF...WHICH WL AID SFC HEATING. WITH TEMPS WARMING TO NEAR
80F...AND DWPTS IN THE U60S TO L70S...SFC BASED CAPE VALUES WL BE
BTWN 2000-2500 J/KG...ESPECIALLY ALONG AND EAST OF THE CPV. EXPECT
ANOTHER ROUND OF STORMS TO REDEVELOP BY EARLY THIS AFTN ACRS THE
EASTERN DACKS...AND BECOME SEVERE AS THEY ENCOUNTER BETTER
INSTABILITY/SHEAR ACRS THE CPV AND MOST OF VT. SOUNDINGS SHOW A
MAINLY UNIDIRECTIONAL WIND FLW THRU 500MB...SUPPORTING LINES OF
STORMS WITH INDIVIDUAL BOW SEGMENTS POSSIBLE...WITH PRIMARY THREAT
BEING STRONG/DAMAGING WINDS. PRE-STORM CHECKLIST SHOWS VERY HIGH
0C LINE AROUND 13KFT THIS AFTN...WHICH INDICATES WE WOULD NEED A
50 TO 55 DBZ TO 35,000 FEET FOR SEVERE HAIL. THEREFORE PRIMARY
THREAT WL BE WINDS...AND GIVEN RECENT SATURATED SOILS...SHALLOW
ROOTED TREES COULD EASILY BE BLOWN DOWN. STORMS SHOULD CLEAR
EASTERN VT BY 8 PM THIS EVENING...BASED ON CRNT RAP AND BTV 4KM
REFLECTIVITY PROGS.
PREVIOUS DISCUSSION...ACTIVE 24-HR PERIOD EXPECTED FOR TODAY/
TONIGHT AS A CD FRNT WILL BEGIN TO PUSH THRU THE AREA. RW/TRW FROM
THE OVERNGT PERIOD STILL SLOWLY PUSHING NORTH THRU CANADIAN BORDER
ZONES ATTM AND SHOULD CLR INTO QUEBEC BFR MAIN PRECIP ARRIVES WITH
FRNT...WHICH IS ONLY TO OUR WEST OVER WESTERN NY/LK ONTARIO. MANY
SPOTS IN THE CWA WILL SEE INSTABILITY INCR DURING THE DAY AS
PSUNNY/MSUNNY WILL ENSUE BFR CONVECTION BEGINS TO
DEVELOP...ALLOWING FOR INCR IN T/TD THROUGHOUT AREA. THIS COMBINED
WITH STRONG SHEAR/LAPSE RATES...LI/S NEARING -4 AND MDL CAPE FROM
BUFKIT SHOWING 1500-2000 J/KG POTENTIAL...WILL ALLOW FOR
DEVELOPMENT OF STRONG TO SEVERE STORMS FOR TODAY/TNGT. SPC(STORM
PREDICTION CENTER) HAS MAJORITY OF CWA UNDER SL RISK FOR SEVERE
CONDITIONS SO HAVE MAINTAINED SEVERE/ENHANCED WORDING IN FORECAST.
MDL PW/S NEARING 1.25-1.60" IN GENERAL WITH LOCALLY HIR AMTS WILL
CREATE QPF AMTS IN GENERAL NEARLY AN INCH FOR ALL AREAS...W/
LOCALLY HIR TOTALS IN HEAVIER DOWNPOURS. W/ SOME AREAS SEEING
TRAINING OF RW/TRW OVERNGT...HYDRO CONCERNS WILL BE AN ISSUE TO
MONITOR. LATEST MDL TREND IS TO BRING BULK OF PRECIP THRU AREA
AFTER MIDNGT TONIGHT. MID-LEVEL DRY AIR WORKING AROUND LOW TO OUR
WEST MAY AID IN SHUTTING DOWN PRECIP QUICKER. FOR NOW WILL KEEP
PRECIP TRENDING DOWN THRU 12Z MONDAY AS TRAINING POTENTIAL MAY
KEEP PRECIP GOING ALONG FRNT A BIT LONGER. TEMP THRU PERIOD NEAR
GUIDANCE...ESPECIALLY EASTERN ZONES WHERE NOT AFFECTED BY CLD
COVER FROM APPORACHING FRNT.
&&
.SHORT TERM /11 PM THIS EVENING THROUGH TUESDAY/...
AS OF 424 AM EDT SUNDAY...GOING INTO MONDAY MORNING...MDLS PUSH
FRNTL BOUNDARY OFF THE NEW ENGLAND COAST...LEAVING THE CWA WITH A
GRADUAL CLRING TREND THRU THE DAY AS SFC HIGH PRESSURE BUILDS EAST
OUT OF THE GREAT LKS REGION. OVER PAST SEVERAL MDL RUNS...UPPER
TROUGH ASSOCIATED W/ THIS SFC FRNT CONTINUES TO SLOWLY PUSH EAST
THRU SOUTHERN PORTIONS OF QUEBEC INTO THE CANADIAN MARITIMES BY
TUESDAY. AS A RESULT WILL CONTINUE TO MENTION SL CHANCE FOR -RW
FOR NE VT THRU EARLY TUESDAY MORNING BFR CLRING OUT. OVERALL TREND
IS FOR NICE WX AS SFC RIDGE REMAINS IN PLACE. STAYING CLOSE TO MDL
GUIDANCE FOR TEMPS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 450 AM EDT SUNDAY...ECMWF AND GFS MODELS SHOW A RIDGE OF
HIGH PRESSURE WILL BUILD INTO THE REGION TUESDAY NIGHT AND WILL
REMAIN OVER THE REGION THROUGH EARLY THURSDAY...WITH FAIR AND DRY
WEATHER EXPECTED. ECMWF AND GFS MODELS SHOW AN UPPER TROUGH OVER
THE WESTERN GREAT LAKES EARLY THURSDAY. THIS UPPER TROUGH WILL
BRING MOISTURE NORTHEAST FROM THE OHIO VALLEY INTO THE REGION ON
THURSDAY AS A STATIONARY FRONTAL BOUNDARY SETS UP ACROSS THE
REGION. ECMWF AND GFS MODELS IN GOOD AGREEMENT IN BRINGING RAIN
SHOWERS TO THE REGION THURSDAY AND FRIDAY. ECMWF AND GFS MODELS
DIFFER ON THE SATURDAY FORECAST WITH THE ECMWF MODEL SHOWING AN
UPPER RIDGE BUILDING INTO THE REGION ON SATURDAY...AND ALSO
BRINGING A DRIER FORECAST TO THE REGION FOR SATURDAY. GFS MODEL
STILL HAS AN UPPER TROUGH OVER THE REGION ON SATURDAY WITH A
CHANCE OF RAIN SHOWERS. GIVEN MODEL DIFFERENCES...WILL OPT TO STAY
WITH PREVIOUS CONTINUITY AND KEEP A CHANCE OF RAIN SHOWERS OVER
THE REGION ON SATURDAY.
&&
.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
THROUGH 12Z MONDAY...AREAS OF MVFR/IFR EXPECTED IN SHOWERS AND
THUNDERSTORMS THROUGH 00Z MONDAY. SOME THUNDERSTORMS TODAY MAY
BECOME SEVERE WITH GUSTY WINDS AND HAIL POSSIBLE. COMPOSITE RADAR
LOOP AS OF 1130Z SUNDAY SHOWING SOME SHOWERS WITH SOME EMBEDDED
THUNDERSTORMS ACROSS THE SAINT LAWRENCE VALLEY IN NORTHERN NEW YORK
AT THIS TIME. EXPECTING STRONG TO POSSIBLE SEVERE THUNDERSTORMS TO
DEVELOP ACROSS THE SAINT LAWRENCE VALLEY IN NORTHERN NEW YORK
AROUND 14Z-18Z TODAY...AND THEN SHIFT EASTWARD. EXPECTING SHOWER
AND THUNDERSTORM ACTIVITY COMING TO AN END IN THE SAINT LAWRENCE
VALLEY IN NORTHERN NEW YORK BY 18Z SUNDAY. EXPECTING WIDESPREAD
STRONG TO SEVERE THUNDERSTORMS TO DEVELOP ACROSS THE REMAINDER OF
THE REGION FROM 16Z-21Z SUNDAY. A MID LEVEL DRY SLOT WILL MOVE
INTO THE REGION LATE THIS AFTERNOON...SO EXPECTING ANY
THUNDERSTORM ACTIVITY TO BE CONFINED TO EASTERN AND SOUTHERN
VERMONT BY 00Z MONDAY. EXPECTING ANY THUNDERSTORM ACTIVITY WILL BE
EAST OF THE REGION BY 03Z MONDAY.
OUTLOOK 12Z MONDAY THROUGH THURSDAY...
12Z MONDAY THROUGH THURSDAY...MAINLY VFR CONDITIONS EXPECTED
THROUGH THURSDAY.
&&
.HYDROLOGY...
SHOWERS AND THUNDERSTORMS WILL DEVELOP THIS AFTERNOON WITH
POTENTIAL FOR LOCALIZED HEAVY RAINFALL. THE STRONGER STORMS WILL
BE CAPABLE OF PRODUCING 1 TO 2 INCHES OF RAIN IN A SHORT PERIOD OF
TIME...WHICH MAY CAUSE ISOLATED FLASH FLOODING...ESPECIALLY IN THE
TRRN. ALSO...MINOR URBAN AND LOW LYING FLOODING WILL BE
POSSIBLE...WITH THESE THUNDERSTORMS. INDIVIDUAL THUNDERSTORMS WILL
MOVE FROM SOUTHWEST TO NORTHEAST AT 20 TO 30 MPH...WITH THE ENITRE BROKEN
LINE SLOWLY MOVING EAST AT 10 TO 15 MPH.
&&
.MARINE...
A LAKE WIND ADVISORY CONTINUES FOR TODAY...EXPECT SOUTH WINDS TO
INCREASE AT 15 TO 25 KNOTS WITH WAVES 1 TO 3 FEET. IN
ADDITION...LAKE THUNDERSTORM ADVISORY CONTINUES WITH THE
EXPECTATION THUNDERSTORMS WILL DEVELOP OVER THE CHAMPLAIN VALLEY
AND OPEN WATERS BY EARLY THIS AFTERNOON.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...JN
NEAR TERM...TABER
SHORT TERM...JN
LONG TERM...WGH
AVIATION...WGH/RJS
HYDROLOGY...
MARINE...
AREA FORECAST DISCUSSION
NWS PENDLETON OR
855 AM PDT SUN JUN 2 2013
.UPDATE...MINOR UPDATES WERE MADE TO THE CURRENT FORECAST. A LARGE
UPPER LEVEL TROUGH OVER WA/ID/MT WILL PUSH AN EMBEDDED WAVE OVER SE
WASHINGTON AND NE OREGON THIS AFTERNOON. THERE IS LIMITED MOISTURE
WITH THE APPROACHING DISTURBANCE...BUT A 100 KNOT JET ALONG THE
BOTTOM OF THE TROUGH WILL RESULT IN SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS FROM THE TRI-CITIES, PENDLETON, AND UKIAH EAST TO THE
IDAHO BORDER. BASED UPON THE HRRR COMPOSITE REFLECTIVITY SHOWING
CONVECTIVE CELLS ACROSS THE WASHINGTON COLUMBIA BASIN...THE FORECAST
WAS UPDATED TO EXTEND ISOLATED THUNDERSTORMS FARTHER WEST TO INCLUDE
THE EASTERN PORTION OF THE LOWER COLUMBIA BASIN. THERE MAY BE A FEW
STRONG THUNDERSTORMS TODAY WITH DIME TO PENNY-SIZE HAIL...BUT SEVERE
STORMS ARE NOT EXPECTED. A FAIRLY TIGHT SURFACE PRESSURE GRADIENT
AND A WEAK MARINE PUSH WILL RESULT IN 20-30 MPH WINDS THROUGH THE
EASTERN SIDE OF THE COLUMBIA RIVER GORGE AND THE KITTITAS VALLEY.
THE SYSTEM WILL HAVE VERY LITTLE IMPACT IN OUR SOUTHERN
ZONES...THEREFORE IT WILL BE MOSTLY SUNNY AND A LITTLE BREEZY ACROSS
CENTRAL OREGON TODAY. THE SYSTEM WILL EXIT THE REGION THIS EVENING
WITH MOST SHOWERS ENDING BY MIDNIGHT. WISTER
&&
.PREV DISCUSSION... /ISSUED 431 AM PDT SUN JUN 2 2013/
LONG TERM...TUESDAY NIGHT THROUGH SATURDAY...HIGH PRESSURE WILL
BUILD OVER THE AREA FOR THE EXTENDED. EXPECT MOSTLY DRY CONDITIONS
AND TEMPERATURES TO INCREASE THROUGH THE WORK WEEK...INTO THE
WEEKEND. EXPECT TEMPERATURES TO BE IN THE MID 80S TO LOWER 90S
ACROSS THE LOWER ELEVATIONS...WITH 70S TO LOWER 80S MOUNTAINS.
MODELS DO INDICATE A FEW WEAK DISTURBANCES THAT MAY PASS IN THE
EXTENDED...BUT ONLY ANTICIPATE OCCASIONAL BREEZY CONDITIONS AND
BRIEF INCREASED CLOUD COVER TO BE ASSOCIATED. WEBER
AVIATION...12Z TAFS...VFR CONDITIONS TO PREVAIL OVER THE NEXT 24
HOURS. SCATTERED CLOUDS AT 5-8 THOUSAND FEET TODAY WITH WINDS
INCREASING IN THE AFTERNOON AT 10-20 KT FROM THE NW WITH A FEW
HIGHER GUSTS. WINDS AND CLOUD COVER WILL DIMINISH AFTER 06Z
TONIGHT. WEBER
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 73 48 75 50 / 10 10 0 0
ALW 74 53 77 55 / 20 20 0 0
PSC 79 51 80 53 / 10 10 0 0
YKM 78 47 79 49 / 10 10 0 0
HRI 77 50 79 52 / 10 10 0 0
ELN 74 48 79 50 / 10 10 0 0
RDM 72 37 77 39 / 10 10 0 0
LGD 69 44 72 46 / 20 20 10 10
GCD 67 43 70 45 / 10 10 0 0
DLS 77 52 80 54 / 10 10 0 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
TODAY : GREEN
MONDAY : GREEN
TUESDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
85/93
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1034 AM EDT SUN JUN 2 2013
.SYNOPSIS...
WARM MOIST AIR OVER OUR REGION WILL BE DISPLACED BY A COLD FRONT
TODAY. BEHIND THE FRONT AN UPPER TROUGH WILL DOMINATE OUR REGION
WITH GENERALLY COOLER AND DRIER CONDITIONS PREVAILING THROUGH MID
WEEK. WET WEATHER WILL RETURN FOR LATE WEEK AS A NEW WEATHER
SYSTEM APPROACHES.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A LINE OF CONVECTION /STILL MAINLY JUST SHOWERS AT 14Z/ CONTINUES
TO MOVE INTO CENTRAL ZONES. BIGGEST QUESTION FOR TODAY IS IF THE
CONVECTION CAN ATTAIN ANY MEASURE OF ORGANIZATION AHEAD OF
APPROACHING COLD FRONT. SHORTWAVE /FROM KY LAST NIGHT/ IS
CURRENTLY SLIDING ACROSS CWA AND SOME ENHANCEMENT TO CONVECTION IS
BEING SEEN...THOUGH STILL JUST ENOUGH TO PRODUCE A FEW BOLTS OF
LIGHTNING. THIS FEATURE WILL SLIDE NE...BECOMING A DIMINISHING
FACTOR IN TODAY/S WEATHER BY 18Z. SO...POTENTIAL FOR STRONGER
STORMS MAY COME DOWN TO HEATING OVER EASTERN SECTIONS. MID-LEVEL
CLOUDS CURRENTLY STREAMING OVERHEAD THOUGH...BUT POTENTIAL FOR
THIS AREA TO BREAK OUT INTO THE SUN THIS AFTERNOON BEHIND EXITING
SHORTWAVE SHOULD ALLOW CAPES TO RISE TO AROUND 1500. SPC DOES
HAVE SE HALF OF FCST AREA OUTLOOKED FOR A SLIGHT RISK OF SEVERE
STORMS AS MID-LEVEL TROUGH AND COLD FRONT ROTATE THROUGH LATER
TODAY. AND HRRR STILL ATTEMPTS TO INITIATE AND ORGANIZE A LINE OF
CONVECTION AFTER 16Z ALONG PRE-FRONTAL TROUGH...BUT AFOREMENTIONED
FEATURES MAY HAVE TO COME TOGETHER JUST RIGHT FOR A STRONGER TSTM
LINE TO HAPPEN BEFORE EXITING CWA TO THE EAST. FOR NOW...WILL
KEEP ENHANCED WORDING GOING IN EASTERN SECTIONS AND SEE HOW THIS
ALL PLAYS OUT.
OTHERWISE...IT WILL BE ANOTHER WARM MUGGY DAY WITH HIGH TEMPS
SLIGHTLY COOLER THAN IN PREVIOUS DAYS DUE TO SHOWERS AND CLOUD
COVER. THIS SHOULD BE THE LAST WIDESPREAD VERY WARM AND HUMID DAY
FOR A WHILE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
STILL SOME UNCERTAINTY AMONG THE SHORT RANGE OPERATIONAL MODELS
AS TO THE TIMING OF THE FRONT THRU SERN PA LATER TONIGHT INTO
EARLY MONDAY. THE NAM IS THE SLOWEST WITH A WAVY FEATURE STILL
STUCK OVER SERN PA INTO EARLY MONDAY...WHILE THE GFS AND ECMWF
HAVE THE SURFACE FRONT ANYWHERE FROM THE CENTRAL DEL MARVA AREA TO
NORTHERN NJ. THE GEFS AND SREF FOLLOW THEIR OPERATIONAL
COUNTERPARTS PRETTY CLOSELY SO ONCE AGAIN I HAD TO SPLIT THE
DIFFERENCE AND KEPT THE SMALL MENTION OF SHOWERS GOING INTO MONDAY
MORNING. I DID DRY THINGS OUT THEREAFTER BUT THE 06Z NAM STILL
LEANS TOWARD THE 00Z SOLUTION OF A SLOWER WAVY FRONT...SO LATER
SHIFTS MAY HAVE TO ADJUST THIS A BIT.
DRIER AND COOLER AIR WILL MOVE IN FROM THE NW OVERNIGHT AND MONDAY
WITH THE LAST OF THE 60S DEWPOINTS BEING SHOVED OFF TO THE SE IN
TIME. HOW FAST THEY EXIT THE REGION ALTOGETHER WILL DEPEND ON THE
FRONT MENTIONED ABOVE.
HIGHS MONDAY WILL BE IN THE CHILLY 60S OVER THE NW...WELL BELOW
NORMAL FOR EARLY JUNE. HIGHS NEAR 80 IN THE SE WILL BE VERY NEAR
NORMAL.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
HIGH PRESSURE BUILDING DOWN OUT OF THE GR LAKES SHOULD PROVIDE FOR
SOME DRY UNEVENTFUL WEATHER TUESDAY WITH PLEASANT TEMPS AND
HUMIDITY.
AS THE HIGH MOVES OFF TO OUR NORTHEAST WE SHOULD SET UP A
SOUTHERLY FLOW OF INCREASING MOIST AIR. MEANWHILE THE MODELS WANT
TO CARVE OUT A BROAD SLOW-MOVING UPPER TROUGH OVER THE EASTERN US
SUGGESTING A PROLONGED PERIOD OF UNSETTLED WEATHER SETTING UP FROM
ABOUT MID WEEK...POSSIBLY INTO NEXT WEEKEND. I REINTRODUCED THE
CHANCES FOR RAIN BY WEDNESDAY AND KEPT THE MENTION OF SHOWERS
RIGHT INTO SUNDAY.
THE EXPECTED DEVELOPMENT OF A NEGATIVE NAO COULD SIGNAL THIS
EASTERN TROUGH STICKING AROUND FOR A WHILE WITH THE GEFS SHOWING
AN ANOMALOUS TROUGH DEVELOPING INTO THE LOWER GR LAKES OUT AS FAR
AS DAY 7.
OF NOTE IS SOME TROPICAL MOISTURE OVER THE BAY OF CAMPECHE. THE
NHC SAYS IT HAS NO CHANCE OF TURING INTO A TROPICAL CYCLONE OVER
THE NEXT COUPLE OF DAYS...BUT THE VARIOUS OPERATIONAL MODELS SEEM
TO WANT TO DRAG AT LEAST SOME OF THE MOISTURE NORTHWARD. AS USUAL
THERE IS NO AGREEMENT ON THE FINE DETAILS WITH THE GFS TAKING THE
SLUG OF MOISTURE OFF THE SERN US COAST...THE ECMWF TAKING THINGS A
FAIR DISTANCE UP THE COAST AND THE CANADIAN TAKING A FULL BLOWN
TROPICAL CYCLONE INTO THE CENTRAL APPALACHIANS BY FRIDAY. COULD BE
AN INTERESTING END OF THE WEEK.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
COLD FRONT WILL APPROACH FROM THE WEST LATER TODAY. BEFORE IT
ARRIVES...SEVERAL BANDS OF SHOWERS AND ISOLATED STORMS TO WORK
ACROSS THE AREA TODAY. VFR FOR MANY SPOTS TODAY...BUT A BAND OF
MVFR LIKELY WITH EASTWARD ADVANCING LINE OF CONVECTION.
PARTIAL CLEARING INTO THE SE BY MID AFTERNOON...WITH POTENTIAL FOR
STRONGER LINE OF TSTMS TO FORM AND POSS IMPACT KIPT-KSEG-KMDT-
KLNS-KTHV THIS AFTERNOON WITH SHORT-LIVED BUT VERY RESTRICTIVE
CONDITIONS ALONG WITH LOCALLY GUSTY WINDS.
OUTLOOK...
MON...LOW CIGS/FOG POSS EARLY OVR W MTNS.
TUE-WED...NO SIG WX EXPECTED.
THU...ISOLD PM THUNDERSTORM IMPACTS POSS W MTNS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE/RXR
NEAR TERM...LA CORTE/RXR
SHORT TERM...LA CORTE
LONG TERM...LA CORTE
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
740 AM EDT SUN JUN 2 2013
.SYNOPSIS...
WARM MOIST AIR OVER OUR REGION WILL BE DISPLACED BY A COLD FRONT
TODAY. BEHIND THE FRONT AN UPPER TROUGH WILL DOMINATE OUR REGION
WITH GENERALLY COOLER AND DRIER CONDITIONS PREVAILING THROUGH MID
WEEK. WET WEATHER WILL RETURN FOR LATE WEEK AS A NEW WEATHER
SYSTEM APPROACHES.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A LINE OF CONVECTION CONTINUES TO MOVE ACROSS MY NW MOUNT IAN
ZONES. THE MOST ORGANIZED ACTIVITY IS UP IN NY STATE...WITH THE
LINE BECOMING PROGRESSIVELY MORE RAGGED LOOKING DOWN INTO SWRN PA.
BIGGEST QUESTION FOR TODAY IS IF THE CONVECTION CAN ATTAIN ANY
MEASURE OF ORGANIZATION AS THE FRONT ENTERS THE REGION. SPS HAS
MUCH OF THE FCST AREA OUTLOOKED FOR A SLIGHT RISK OF SEVERE
STORMS...BUT AS USUAL MUCH WILL DEPEND ON HEATING. SHORT RANGE
HIGH RES GUIDANCE IS HAVING A HARD TIME GRASPING THE MODE OF
CONVECTION THAT WE CAN EXPECT WITH THE FRONT. THE RAP SHOWS
DISORGANIZED SHOWERS/STORMS WHILE THE HRRR HAS MORE OF A LINEAR
LOOKING FEATURE DEVELOPING OVER CENTRAL PA BY MID MORNING...BUT
CURIOUSLY WEAKENS THE LINE AS IT MOVES EAST DURING WHAT SHOULD
BECOME THE MOST UNSTABLE PART OF THE DAY. THIS DOES A LOT TO LOWER
CONFIDENCE IN TRYING TO TIME THE BEST CHANCES FOR RAIN AND STORMS
TODAY. AS FOR POPS...I ENDED UP GOING WITH A GMOS/SREF COMPROMISE
AND HAVE A LIKELY CHANCE OF SHOWERS AND THUNDER FOR MOST OF THE
AREA THIS MORNING INTO THIS AFTERNOON...BUT TIMING IS TOUGH.
IT WILL BE ANOTHER WARM MUGGY DAY WITH SLIGHTLY COOLER HIGH TEMPS
DUE TO SHOWERS AND CLOUD COVER. THIS SHOULD BE THE LAST
WIDESPREAD VERY WARM AND HUMID DAY FOR A WHILE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
STILL SOME UNCERTAINTY AMONG THE SHORT RANGE OPERATIONAL MODELS
AS TO THE TIMING OF THE FRONT THRU SERN PA LATER TONIGHT INTO
EARLY MONDAY. THE NAM IS THE SLOWEST WITH A WAVY FEATURE STILL
STUCK OVER SERN PA INTO EARLY MONDAY...WHILE THE GFS AND ECMWF
HAVE THE SURFACE FRONT ANYWHERE FROM THE CENTRAL DEL MARVA AREA TO
NORTHERN NJ. THE GEFS AND SREF FOLLOW THEIR OPERATIONAL
COUNTERPARTS PRETTY CLOSELY SO ONCE AGAIN I HAD TO SPLIT THE
DIFFERENCE AND KEPT THE SMALL MENTION OF SHOWERS GOING INTO MONDAY
MORNING. I DID DRY THINGS OUT THEREAFTER BUT THE 06Z NAM STILL
LEANS TOWARD THE 00Z SOLUTION OF A SLOWER WAVY FRONT...SO LATER
SHIFTS MAY HAVE TO ADJUST THIS A BIT.
DRIER AND COOLER AIR WILL MOVE IN FROM THE NW OVERNIGHT AND MONDAY
WITH THE LAST OF THE 60S DEWPOINTS BEING SHOVED OFF TO THE SE IN
TIME. HOW FAST THEY EXIT THE REGION ALTOGETHER WILL DEPEND ON THE
FRONT MENTIONED ABOVE.
HIGHS MONDAY WILL BE IN THE CHILLY 60S OVER THE NW...WELL BELOW
NORMAL FOR EARLY JUNE. HIGHS NEAR 80 IN THE SE WILL BE VERY NEAR
NORMAL.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
HIGH PRESSURE BUILDING DOWN OUT OF THE GR LAKES SHOULD PROVIDE FOR
SOME DRY UNEVENTFUL WEATHER TUESDAY WITH PLEASANT TEMPS AND
HUMIDITY.
AS THE HIGH MOVES OFF TO OUR NORTHEAST WE SHOULD SET UP A
SOUTHERLY FLOW OF INCREASING MOIST AIR. MEANWHILE THE MODELS WANT
TO CARVE OUT A BROAD SLOW-MOVING UPPER TROUGH OVER THE EASTERN US
SUGGESTING A PROLONGED PERIOD OF UNSETTLED WEATHER SETTING UP FROM
ABOUT MID WEEK...POSSIBLY INTO NEXT WEEKEND. I REINTRODUCED THE
CHANCES FOR RAIN BY WEDNESDAY AND KEPT THE MENTION OF SHOWERS
RIGHT INTO SUNDAY.
THE EXPECTED DEVELOPMENT OF A NEGATIVE NAO COULD SIGNAL THIS
EASTERN TROUGH STICKING AROUND FOR A WHILE WITH THE GEFS SHOWING
AN ANOMALOUS TROUGH DEVELOPING INTO THE LOWER GR LAKES OUT AS FAR
AS DAY 7.
OF NOTE IS SOME TROPICAL MOISTURE OVER THE BAY OF CAMPECHE. THE
NHC SAYS IT HAS NO CHANCE OF TURING INTO A TROPICAL CYCLONE OVER
THE NEXT COUPLE OF DAYS...BUT THE VARIOUS OPERATIONAL MODELS SEEM
TO WANT TO DRAG AT LEAST SOME OF THE MOISTURE NORTHWARD. AS USUAL
THERE IS NO AGREEMENT ON THE FINE DETAILS WITH THE GFS TAKING THE
SLUG OF MOISTURE OFF THE SERN US COAST...THE ECMWF TAKING THINGS A
FAIR DISTANCE UP THE COAST AND THE CANADIAN TAKING A FULL BLOWN
TROPICAL CYCLONE INTO THE CENTRAL APPALACHIANS BY FRIDAY. COULD BE
AN INTERESTING END OF THE WEEK.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
MAIN BATCH OF STORMS MOVED ACROSS NW PA OVERNIGHT...IN THE
AREA WITH THE STRONGER LLJ.
SEVERAL BANDS OF SHOWERS AND ISOLATED STORMS TO WORK ACROSS
THE AREA TODAY. VFR FOR MANY SPOTS TODAY...BUT IFR AND MVFR
AT TIMES...ESPECIALLY BFD AND JST THIS MORNING.
PARTIAL CLEARING INTO THE SE BY LATE AFTERNOON...BUT WEAK
WAVE MAY BRING SOME LOWER CIGS AND SHOWERS TO THE SE
TONIGHT.
OUTLOOK...
MON...LOW CIGS/FOG POSS EARLY OVR W MTNS.
TUE-WED...NO SIG WX EXPECTED.
THU...ISOLD PM THUNDERSTORM IMPACTS POSS W MTNS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LA CORTE
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1053 AM CDT SUN JUN 2 2013
.UPDATE...
SEE MORNING UPDATE.
&&
.DISCUSSION...
RAIN HAS PUSHED TO THE COAST AND WILL CONTINUE TO PUSH AWAY FROM
SE TX. A WEAK COLD FRONT EXTENDED FROM EL DORADO ARKANSAS TO
GALVESTON AND THEN WEST TOWARD COTULLA. DRIER AIR HAS BEGUN TO
FILTER INTO SE TX WITH SFC DEW PTS NOW IN THE MID/UPPER 60S.
CONSIDERABLE CLOUD COVER AND WET GROUND WILL LIKELY LIMIT HEATING
TODAY SO HAVE TRIMMED MAX TEMPS A FEW DEGREES. CLOUDS SHOULD BEGIN
TO ERODE IN THE NEXT HOUR OR SO AND PLENTY OF SUNSHINE IS STILL
EXPECTED BY LATE AFTERNOON. RAP MODEL SHOWS SOME REDVELOPMENT
ALONG THE COAST LATE THIS AFTERNOON AND WILL LEAVE 20 POPS IN TO
ACCOUNT FOR THE POSSIBILITY. NEW ZONES OUT BY 11 AM. 43
&&
.PREV DISCUSSION... /ISSUED 655 AM CDT SUN JUN 2 2013/
DISCUSSION...
12Z AVIATION DISCUSSION.
AVIATION...
A LINE OF STRONG TO SEVERE THUNDERSTORMS WILL MOVE THROUGH THE
HOUSTON METRO AREA BETWEEN 12 AND 16Z THIS MORNING...AND OFF THE
COAST BETWEEN 14 AND 18Z. WINDS MAY BRIEFLY GUST FROM THE NORTH AT
25 TO 25 KNOTS WITH VISIBILITIES DROPPING TO 1 MILE IN HEAVY RAIN.
CONDITIONS SHOULD GRADUALLY IMPROVE BEHIND THE LINE WITH ALL
TERMINALS VFR BY THIS AFTERNOON. SKIES SHOULD CLEAR OUT OVERNIGHT
WITH LIGHT NORTHERLY WINDS. 44
PREV DISCUSSION... /ISSUED 445 AM CDT SUN JUN 2 2013/
DISCUSSION...
A LINE OF THUNDERSTORMS IS BEGINNING TO FILL IN FROM SOUTH OF
LUFKIN TO COLLEGE STATION. RAIN GAUGES IN TRINITY COUNTY ARE
PICKING UP AS MUCH AS 2.2 INCHES IN 3 HRS AND AS MUCH AS 2 INCHES
OF THAT HAS FALLEN IN THE LAST HOUR. ALSO SEEING A SIGNS OF A REAR
INFLOW JET DEVELOPING IN THE BACK SIDE OF CONVECTION CLOSING IN ON
BRYAN/COLLEGE STATION. BASED ON IR IMAGERY SEEMS CLOUD TOPS ARE
COOLING MORE SO EXPECT DEEP CONVECTION TO CONTINUE THROUGH THE
MORNING. THE MAIN THREAT WILL BE HEAVY RAINFALL ON THE ORDER OF 2
TO 3 INCHES AN HOUR LIKE ALREADY OBSERVED. STORM MOTIONS ARE
EXPECTED TO BE SLOW AS IN 10 TO 2O MPH BUT COULD SEE CELLS
CONTINUE TO DEVELOP ALONG A FRONT PUSHING INTO THE AREA WHICH
COULD TRAIN ACROSS AREAS THAT HAVE ALREADY RECEIVED RAINFALL. SFC
ANALYSIS AT 09Z SHOWS FRONTAL BOUNDARY SLOWLY PUSHING SOUTH FROM
THE ARLATEX THROUGH C TX INTO THE NW HILL COUNTRY. LOOK FOR
CURRENT CONVECTION TO SLOWLY WORK SOUTH AHEAD OF THE FRONT AND
POSSIBLY OUT RUN IT BY A GOOD BIT. THE 00Z HIRES-WRF-ARW/TXTECH
WRF AND HRRR ALL SHOW CURRENT LINE OF CONVECTION WORKING SOUTH
THROUGH SE TX IN A BROKEN LINE. THE LINE THEN WEAKENS AS IT
APPROACHES THE COAST BETWEEN 15Z-18Z. DECIDED TO KEEP SOME 50/60
POPS THROUGH 12-15Z AND THEN GRADUALLY DECREASE RAIN CHANCES.
LOOKS LIKE THIS PART OF THE FORECAST MAY GO THROUGH ADDITIONAL
MODIFICATIONS DEPENDING ON HOW THE CONVECTION EVOLVES THIS
MORNING. DO THINK THIS CONVECTION SHOULD WORK OVER AND STABILIZE
THE ATMOSPHERE FOR THE AFTERNOON SO 20 POPS FOR THE AFTERNOON
LOOKS GOOD BUT IT COULD BE DRY.
AS IT HAS BEEN DISCUSSED BEFORE...MAIN HAZARD THIS MORNING WILL
BE HEAVY RAINFALL. UPPER LEVEL ANALYSIS SHOWS A TROUGH AXIS
WORKING THROUGH THE AREA AND THERE MAY BE ENOUGH UPPER LEVEL
SUPPORT TO KEEP CONVECTION GOING THIS MORNING. EXPECT UPPER LEVEL
ASCENT TO WEAKEN DURING THE AFTERNOON AND CONVERGENCE ALONG THE
FRONT TO WEAKEN AS WELL. THUS BEST CHANCES FOR HEAVY RAIN STILL
THIS MORNING AND THREAT DIMINISHING IN THE AFTERNOON. PRECIP WATER
VALUES THIS MORNING PEAK INVOF CONVECTION AROUND 1.8-2.0 INCHES
AND DECREASE THIS AFTERNOON TO BELOW 1.5 INCHES.
AS FOR THE REST OF THE FORECAST...MODELS STILL BRING WEAK FRONT
TO THE COAST AND POSSIBLY OFF THE COAST. EXPECT SFC DEWPOINT TEMPS
TO DROP INTO THE LOW 60S WHICH WILL SEEM QUITE A BIT DRIER THAN
THE MID 70S DEWPOINTS OF LATE. THIS ALSO MEANS SEASONABLE MIN
TEMPS IN THE MID 60S FOR MON/TUE. EXPECT DRY CONDITIONS TO PERSIST
AS UPPER LEVEL RIDGING BUILDS OVER S TX THROUGH MID WEEK. RIDGE
DOES SHOW SIGNS OF BREAKING DOWN AGAIN FOR THE END OF THE WEEK
WITH AN UPPER LOW OVER THE N PLAINS/MIDWEST/GREAT LAKES. THIS
INTRODUCES NW FLOW ALOFT OVER TX FOR THE END OF THE WEEK WHICH MAY
ALSO SUPPORT A WEAK FRONT MOVING INTO TX ALONG WITH A SERIES OF
WEAK SHORTWAVES THAT COULD INITIATE A FEW ROUNDS OF CONVECTION
ALONG THE RED RIVER AND N TX. POSSIBLE SOME OF THIS CONVECTION
COULD WORK INTO SE TX. WILL KEEP 20 POPS FOR THE END OF THE WEEK
WITH INCREASED MOISTURE AND FAVORABLE UPPER LEVEL PATTERN.
AS WITH TROPICAL SEASON WILL KEEP AN EYE ON CONVECTION IN THE BAY
OF CAMPECHE AND YUCATAN PENINSULA. BOTH GFS/ECMWF SUPPORT
CONVECTION BECOMING ORGANIZED AGAIN FROM REMNANTS OF BARBARA BY
TUESDAY. BOTH MODELS ALSO BRING THIS NEW SYSTEM INTO FLORIDA
THUR/FRI TIME FRAME. THERE WILL BE A DECENT AMOUNT OF WIND SHEAR
SO TOUGH TO KNOW HOW ORGANIZED THE SYSTEM WILL BECOME. NONETHELESS
ALL INDICATIONS ARE THAT THIS WILL NOT BE A THREAT FOR THE TX
COAST.
39
MARINE...
LIGHT ONSHORE FLOW SHOULD BECOME LIGHT AND VARIABLE BY THIS
AFTERNOON IN ADVANCE OF A WEAK COLD FRONT. LIGHT EAST TO SOUTHEAST
WINDS AND 1 TO 2 FOOT SEAS WILL BE THE PREVAILING CONDITION
THROUGH THE MAJORITY OF NEXT WEEK BECAUSE OF A VERY LIGHT PRESSURE
GRADIENT BEHIND THE FRONT. 44
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 89 64 92 68 93 / 20 10 0 0 0
HOUSTON (IAH) 89 67 92 69 93 / 20 10 0 0 0
GALVESTON (GLS) 85 75 88 76 88 / 60 10 0 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...43
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
655 AM CDT SUN JUN 2 2013
.DISCUSSION...
12Z AVIATION DISCUSSION.
&&
.AVIATION...
A LINE OF STRONG TO SEVERE THUNDERSTORMS WILL MOVE THROUGH THE
HOUSTON METRO AREA BETWEEN 12 AND 16Z THIS MORNING...AND OFF THE
COAST BETWEEN 14 AND 18Z. WINDS MAY BRIEFLY GUST FROM THE NORTH AT
25 TO 25 KNOTS WITH VISIBILITIES DROPPING TO 1 MILE IN HEAVY RAIN.
CONDITIONS SHOULD GRADUALLY IMPROVE BEHIND THE LINE WITH ALL
TERMINALS VFR BY THIS AFTERNOON. SKIES SHOULD CLEAR OUT OVERNIGHT
WITH LIGHT NORTHERLY WINDS. 44
&&
.PREV DISCUSSION... /ISSUED 445 AM CDT SUN JUN 2 2013/
DISCUSSION...
A LINE OF THUNDERSTORMS IS BEGINNING TO FILL IN FROM SOUTH OF
LUFKIN TO COLLEGE STATION. RAIN GAUGES IN TRINITY COUNTY ARE
PICKING UP AS MUCH AS 2.2 INCHES IN 3 HRS AND AS MUCH AS 2 INCHES
OF THAT HAS FALLEN IN THE LAST HOUR. ALSO SEEING A SIGNS OF A REAR
INFLOW JET DEVELOPING IN THE BACK SIDE OF CONVECTION CLOSING IN ON
BRYAN/COLLEGE STATION. BASED ON IR IMAGERY SEEMS CLOUD TOPS ARE
COOLING MORE SO EXPECT DEEP CONVECTION TO CONTINUE THROUGH THE
MORNING. THE MAIN THREAT WILL BE HEAVY RAINFALL ON THE ORDER OF 2
TO 3 INCHES AN HOUR LIKE ALREADY OBSERVED. STORM MOTIONS ARE
EXPECTED TO BE SLOW AS IN 10 TO 2O MPH BUT COULD SEE CELLS
CONTINUE TO DEVELOP ALONG A FRONT PUSHING INTO THE AREA WHICH
COULD TRAIN ACROSS AREAS THAT HAVE ALREADY RECEIVED RAINFALL. SFC
ANALYSIS AT 09Z SHOWS FRONTAL BOUNDARY SLOWLY PUSHING SOUTH FROM
THE ARLATEX THROUGH C TX INTO THE NW HILL COUNTRY. LOOK FOR
CURRENT CONVECTION TO SLOWLY WORK SOUTH AHEAD OF THE FRONT AND
POSSIBLY OUT RUN IT BY A GOOD BIT. THE 00Z HIRES-WRF-ARW/TXTECH
WRF AND HRRR ALL SHOW CURRENT LINE OF CONVECTION WORKING SOUTH
THROUGH SE TX IN A BROKEN LINE. THE LINE THEN WEAKENS AS IT
APPROACHES THE COAST BETWEEN 15Z-18Z. DECIDED TO KEEP SOME 50/60
POPS THROUGH 12-15Z AND THEN GRADUALLY DECREASE RAIN CHANCES.
LOOKS LIKE THIS PART OF THE FORECAST MAY GO THROUGH ADDITIONAL
MODIFICATIONS DEPENDING ON HOW THE CONVECTION EVOLVES THIS
MORNING. DO THINK THIS CONVECTION SHOULD WORK OVER AND STABILIZE
THE ATMOSPHERE FOR THE AFTERNOON SO 20 POPS FOR THE AFTERNOON
LOOKS GOOD BUT IT COULD BE DRY.
AS IT HAS BEEN DISCUSSED BEFORE...MAIN HAZARD THIS MORNING WILL
BE HEAVY RAINFALL. UPPER LEVEL ANALYSIS SHOWS A TROUGH AXIS
WORKING THROUGH THE AREA AND THERE MAY BE ENOUGH UPPER LEVEL
SUPPORT TO KEEP CONVECTION GOING THIS MORNING. EXPECT UPPER LEVEL
ASCENT TO WEAKEN DURING THE AFTERNOON AND CONVERGENCE ALONG THE
FRONT TO WEAKEN AS WELL. THUS BEST CHANCES FOR HEAVY RAIN STILL
THIS MORNING AND THREAT DIMINISHING IN THE AFTERNOON. PRECIP WATER
VALUES THIS MORNING PEAK INVOF CONVECTION AROUND 1.8-2.0 INCHES
AND DECREASE THIS AFTERNOON TO BELOW 1.5 INCHES.
AS FOR THE REST OF THE FORECAST...MODELS STILL BRING WEAK FRONT
TO THE COAST AND POSSIBLY OFF THE COAST. EXPECT SFC DEWPOINT TEMPS
TO DROP INTO THE LOW 60S WHICH WILL SEEM QUITE A BIT DRIER THAN
THE MID 70S DEWPOINTS OF LATE. THIS ALSO MEANS SEASONABLE MIN
TEMPS IN THE MID 60S FOR MON/TUE. EXPECT DRY CONDITIONS TO PERSIST
AS UPPER LEVEL RIDGING BUILDS OVER S TX THROUGH MID WEEK. RIDGE
DOES SHOW SIGNS OF BREAKING DOWN AGAIN FOR THE END OF THE WEEK
WITH AN UPPER LOW OVER THE N PLAINS/MIDWEST/GREAT LAKES. THIS
INTRODUCES NW FLOW ALOFT OVER TX FOR THE END OF THE WEEK WHICH MAY
ALSO SUPPORT A WEAK FRONT MOVING INTO TX ALONG WITH A SERIES OF
WEAK SHORTWAVES THAT COULD INITIATE A FEW ROUNDS OF CONVECTION
ALONG THE RED RIVER AND N TX. POSSIBLE SOME OF THIS CONVECTION
COULD WORK INTO SE TX. WILL KEEP 20 POPS FOR THE END OF THE WEEK
WITH INCREASED MOISTURE AND FAVORABLE UPPER LEVEL PATTERN.
AS WITH TROPICAL SEASON WILL KEEP AN EYE ON CONVECTION IN THE BAY
OF CAMPECHE AND YUCATAN PENINSULA. BOTH GFS/ECMWF SUPPORT
CONVECTION BECOMING ORGANIZED AGAIN FROM REMNANTS OF BARBARA BY
TUESDAY. BOTH MODELS ALSO BRING THIS NEW SYSTEM INTO FLORIDA
THUR/FRI TIME FRAME. THERE WILL BE A DECENT AMOUNT OF WIND SHEAR
SO TOUGH TO KNOW HOW ORGANIZED THE SYSTEM WILL BECOME. NONETHELESS
ALL INDICATIONS ARE THAT THIS WILL NOT BE A THREAT FOR THE TX
COAST.
39
MARINE...
LIGHT ONSHORE FLOW SHOULD BECOME LIGHT AND VARIABLE BY THIS
AFTERNOON IN ADVANCE OF A WEAK COLD FRONT. LIGHT EAST TO SOUTHEAST
WINDS AND 1 TO 2 FOOT SEAS WILL BE THE PREVAILING CONDITION
THROUGH THE MAJORITY OF NEXT WEEK BECAUSE OF A VERY LIGHT PRESSURE
GRADIENT BEHIND THE FRONT. 44
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 89 64 92 68 93 / 30 10 0 0 0
HOUSTON (IAH) 91 67 92 69 93 / 70 10 0 0 0
GALVESTON (GLS) 87 75 88 76 88 / 60 10 0 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...39
AVIATION/MARINE...44
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1016 AM CDT SUN JUN 2 2013
.UPDATE...LOW CLOUDS PERSIST ACROSS SOUTHERN WISCONSIN THIS
MORNING DUE TO A COOLER AIRMASS THAT MOVED IN BEHIND DEPARTING LOW
PRESSURE OVERNIGHT. THERE ARE SOME SIGNS THAT THE STRONG EARLY
JUNE SUN IS STARTING TO CHIP AWAY AT THE CLOUD DECK...WITH A HOLE
DEVELOPING JUST TO THE NORTH...AND SOME OF THE STRATUS TAKING A
CELLULAR APPEARANCE TO THE NORTH AND WEST. THERE AREA SOME
DIFFERENCES IN NAM...RAP...AND LOCAL WRF MODEL LOW LEVEL RH FOR
THE REMAINDER OF THE DAY. THE NAM DRIES THINGS OUT THE
QUICKEST...BY EARLY AFTERNOON...WITH THE RAP HOLDING ON TO HIGHER
RH INTO EARLY EVENING. THERE IS A GOOD CHANCE THOUGH THAT ANY
HOLES THAT DO FORM WILL LIKELY BE FILLED WITH CUMULUS
DEVELOPMENT...SO NOT EXPECTING MUCH SUN TODAY. WITH 925 MB TEMPS
ONLY RISING TO ABOUT 10C BY LATE AFTERNOON...UPPER 50S TO LOW 60S
FOR HIGH TEMPS STILL SEEMS REASONABLE.
&&
.AVIATION/18Z TAFS/...MVFR CLOUD DECK WILL LIKELY CONTINUE THROUGH
LATE MORNING INTO EARLY AFTERNOON. THERE ARE SOME DIFFERENCES AMONG
SHORT TERM MODELS AS TO WHEN CONDITIONS WILL IMPROVE...WITH THE
RAP HOLDING ONTO SOME LOW CLOUDS INTO EARLY EVENING. GENERALLY
SPLIT THE TIMING DIFFERENCE FOR NOW...EXPECTING VFR CONDITIONS TO
RETURN BY MID AFTERNOON.
LOOKS VERY QUIET TONIGHT AND TOMORROW AS HIGH PRESSURE SLIDES
OVERHEAD. WINDS SHOULD BE LIGHT WITH SKIES TURNING MOSTLY CLEAR.
&&
.PREV DISCUSSION... /ISSUED 312 AM CDT SUN JUN 2 2013/
TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM TO HIGH.
COOLER BUT QUIET WEATHER IS IN STORE FOR SOUTHERN WISCONSIN TODAY.
SURFACE LOW PRESSURE PUSHES OFF TO THE EAST THIS MORNING WITH HIGH
PRESSURE DRIFTING IN FROM THE WEST. PRETTY GOOD COLD AIR ADVECTION
ON NORTHERLY WINDS WILL BE ONGOING THROUGH THE MORNING.
THIS...COUPLED WITH PERSISTENT CYCLONIC FLOW ALOFT...WILL RESULT
IN PLENTY OF CLOUDS TODAY...GRADUALLY CLEARING FROM THE NORTHWEST
LATE THIS AFTERNOON OR EVENING. HIGHS TODAY WILL BE 15 TO 20
DEGREES COOLER THAN YESTERDAY.
THE HIGH PRESSURE RIDGE WILL BE OVERHEAD TONIGHT. LIGHT WINDS AND
DRY AIR WILL ALLOW TEMPS TO COOL WELL INTO THE 40S...POSSIBLY SOME
UPPER 30S IN FAVORED LOW SPOTS. THE LOW TEMP FORECAST COULD BE
RUINED IF THOSE CLOUDS HANG ON TOO LONG...THIS WOULD KEEP THEM UP
QUITE A BIT.
MONDAY THROUGH TUESDAY NIGHT...FORECAST CONFIDENCE IS MEDIUM TO
HIGH.
SHORT TERM MODELS SHOW HIGH PRESSURE OVER THE REGION MONDAY
SLIDING EASTWARD MONDAY NIGHT. DRY AIRMASS OVER THE REGION WILL
BRING QUIET WEATHER. TEMPERATURES WILL CONTINUE TO BE COOL DURING
THIS TIME.
500MB LOW OVER NORTH DAKOTA ON TUESDAY WILL SLOWLY SHIFT INTO WEST
CENTRAL MINNESOTA BY LATE TUESDAY NIGHT. ASSOCIATED SURFACE LOW
PRESSURE WILL WEAKEN AS IT SHIFTS SOUTHEAST INTO SOUTHERN
MINNESOTA FROM THE DAKOTAS. AREA OF MODEST 850MB WARM AIR
ADVECTION...AND 850MB TO 700MB LAYER Q VECTOR CONVERGENCE...ARE
EXPECTED TO SHIFT ACROSS THE AREA TUESDAY INTO TUESDAY NIGHT.
AREA FORECAST SOUNDINGS FROM NAM/GFS SHOW A GENERAL TOP DOWN
MOISTENING OF THE AIR COLUMN ACROSS THE AREA...MORE SO ON THE GFS
THAN THE NAM. CONTINUED INCREASING POP TREND FROM WEST TO EAST
TUESDAY AND TUESDAY NIGHT FOR NOW. MAY NEED TO INCREASE POPS IN
LATER FORECASTS FOR TUESDAY NIGHT...IF BETTER COLUMN MOISTURE IS
FOUND. THUNDER MENTION WAS REMOVED TUESDAY NIGHT...AS LITTLE TO
NO INSTABILITY REMAINED IN AREA FORECAST SOUNDINGS. TEMPERATURES
WILL REMAIN COOL DURING THIS TIME...WITH ONSHORE WINDS.
WEDNESDAY THROUGH SATURDAY...FORECAST CONFIDENCE IS MEDIUM.
GFS/ECMWF CONTINUE TO SHOW FAIRLY SIMILAR TRENDS FOR MOST OF THIS
PERIOD ACROSS THE REGION. THEY BRING THE 500MB LOW EAST ACROSS THE
REGION WEDNESDAY NIGHT INTO EARLY THURSDAY. GFS KEEPS SHORTWAVE
TROUGH OVER THE REGION INTO THURSDAY NIGHT...BEFORE SLIDING EAST
ON FRIDAY. THE ECMWF IS QUICKER WITH THE SHORTWAVE TROUGH EXITING
THE AREA THURSDAY.
DECENT COLUMN MOISTURE REMAINS OVER THE AREA PER GFS FORECAST
SOUNDINGS WEDNESDAY...THEN BECOME DRY IN THE MID LEVELS WEDNESDAY
NIGHT INTO THURSDAY. THE LOW LEVELS REMAIN SATURATED DURING THIS
TIME. WILL CONTINUE USING CONSENSUS POPS WEDNESDAY INTO THURSDAY
NIGHT ACROSS THE AREA. AGAIN...MAY NEED HIGHER POPS DURING THIS
TIME IF MOISTURE IN AIR COLUMN BECOMES DEEPER.
KEPT SLIGHT CHANCES FOR THUNDER WEDNESDAY INTO WEDNESDAY
NIGHT...BUT COULD BE REMOVED IN LATER FORECASTS IF ELEVATED CAPE
CONTINUES TO BE VERY WEAK. ONSHORE WINDS WILL CONTINUE TO KEEP THE
AREA COOL.
GFS KEEPS HIGH PRESSURE IN THE AREA FRIDAY INTO SATURDAY...WITH
THE ECMWF SHIFTING THE HIGH TO THE EAST...AND A 500MB SHORTWAVE
TROUGH SLIDES EAST ACROSS NORTHERN WISCONSIN. GIVEN THE
DIFFERENCES THIS FAR OUT...WILL USE CONSENSUS POPS AND
TEMPERATURES FOR THIS PERIOD.
AVIATION/12Z TAFS/...
MVFR CIGS ACROSS THE AREA THIS MORNING WILL GRADUALLY LIFT TO VFR
CIGS THIS AFTERNOON. THEN CLEARING IS EXPECTED TO ARRIVE BY EARLY
TO MID EVENING...FIRST AT KMSN...FOLLOWED BY KMKE/KUES/KENW. NORTH
TO NORTHWEST WINDS WILL SHIFT TO NORTHEAST AT KMKE/KENW EARLY THIS
AFTERNOON.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...DDV
TODAY/TONIGHT AND AVIATION/MARINE...DAVIS
MONDAY THROUGH SATURDAY...WOOD
AREA FORECAST DISCUSSION
NWS TUCSON AZ
925 AM MST SUN JUN 2 2013
.SYNOPSIS...HIGH PRESSURE ANCHORED OVER NORTHERN MEXICO WILL BRING
DRY AND HOT CONDITIONS THIS WEEK.
&&
.DISCUSSION...DRY SOUTHWESTERLY FLOW WITH HIGH PRESSURE FROM
NORTHERN MEXICO DOMINATING OUR WEATHER. MOISTURE INCREASE THROUGH
NEW MEXICO WILL GENERALLY STAY EAST OF OUR AREA WITH ONLY A BIT OF
LOW LEVEL MOISTURE SPILLING OVER THE STATE LINE. PERHAPS ENOUGH FOR
ISOLATED CONVECTION IN THE FAR EASTERN MOUNTAINS. WITH A HEAD START
ON YESTERDAY DUE TO HIGHER OVERNIGHT LOWS AND THE POTENTIAL
SUGGESTED BY THE 12Z KTWC SOUNDING WE TWEAKED FORECAST TEMPERATURES
UP A TAD. BASED ON LATEST TRENDS AND HRRR WE ALSO TRENDED CLOUD
COVER AND FAR EASTERN MOUNTAIN CONVECTION DOWN A LITTLE THIS
AFTERNOON AND EARLY EVENING.
&&
.PREV DISCUSSION...HIGH PRESSURE ALOFT WAS CENTERED OVER SRN
CHIHUAHUA WITH A SHORTWAVE TROUGH JUST OFF THE SRN CALIFORNIA COAST
EARLY THIS MORNING. MEANWHILE...LOWER-LEVEL ELY FLOW WAS ADVECTING
MOISTURE WWD ACROSS SRN NEW MEXICO. BASED ON VARIOUS 02/00Z NWP
MODELS...HAVE MAINTAINED ISOLD SHOWERS AND THUNDERSTORMS NEAR THE
NEW MEXICO BORDER THIS AFTERNOON AND EARLY THIS EVENING. ANY
SHOWERS/TSTMS WILL END BY MIDNIGHT TONIGHT.
DRY SWLY FLOW ALOFT WILL THEN PREVAIL MON-TUE IN RESPONSE TO A WEAK
LOW PRESSURE SYSTEM OFF THE SRN CALIFORNIA COAST AND HIGH PRESSURE
ALOFT CENTERED OVER CHIHUAHUA. VERY DRY REGIME TO CONTINUE WED-THUR
AS WEAK WLY FLOW ALOFT WED TRANSITIONS TO NWLY FLOW ON THUR.
FOR FRI-SAT...02/00Z GFS/ECWMF WERE VERY SIMILAR WITH DEVELOPING A
REX BLOCK JUST OFF THE WEST COAST...WITH HIGH PRESSURE ALOFT
CENTERED NEAR THE NRN CALIFORNIA COAST AND LOW PRESSURE CENTERED OFF
THE NRN BAJA CALIFORNIA COAST. THE ECMWF WAS MORE-ROBUST VERSUS THE
GFS WITH MOVING MOISTURE MAINLY ABOVE 600 MB SEWD ACROSS SE AZ. A
BLEND OF THE GFS/ECMWF YIELDED MOSTLY CLEAR SKIES FRI-SAT.
HIGH TEMPS THIS AFTERNOON WILL BE ABOUT 1-2 DEGS F HOTTER VERSUS SAT
AFTERNOON. A FEW LOCALES MAY APPROACH OR EVEN EXCEED RECORD TEMPS
THIS AFTERNOON...INCLUDING KTUS. A FEW DEGREES OF MINOR COOLING WILL
OCCUR MON FOLLOWED BY NO SIGNIFICANT CHANGE IN DAYTIME TEMPS TUE-SAT.
&&
.AVIATION...SCT CLOUDS AT 8-12K FT AGL MAINLY EAST OF KTUS WITH
ISOLD -TSRA NEAR THE NEW MEXICO BORDER THIS AFTERNOON AND THIS
EVENING. OTHERWISE...SKC-SCT CLOUDS ABOVE 20K FT AGL THRU MONDAY
MORNING OR 03/12Z. SURFACE WIND THIS AFTERNOON AND THIS EVENING
WLY/SWLY 10-18 KTS WITH GUSTS TO NEAR 25 KTS. OTHERWISE...SURFACE
WIND LESS THAN 10 KTS. AVIATION DISCUSSION NOT UPDATED FOR TAF
AMENDMENTS.
&&
.FIRE WEATHER...EXPECT ISOLATED MAINLY DRY THUNDERSTORMS THIS
AFTERNOON AND EARLY THIS EVENING NEAR THE NEW MEXICO BORDER.
OTHERWISE...DRY CONDITIONS WITH HOT DAYTIME TEMPERATURES WILL
PREVAIL THIS WEEK. DAYTIME MINIMUM RELATIVE HUMIDITIES WILL
GENERALLY BE IN THE SINGLE DIGITS TO LOWER TEENS WITH FAIR TO POOR
OVERNIGHT RECOVERIES. NORMAL DIURNAL WIND TRENDS WILL OCCUR...WITH
GUSTINESS DURING THE AFTERNOON HOURS DUE TO STRONG DAYTIME HEATING.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
MEYER/RASMUSSEN
AREA FORECAST DISCUSSION
NWS PUEBLO CO
324 PM MDT SUN JUN 2 2013
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 318 PM MDT SUN JUN 2 2013
MAIN CONCERN IS THE POTENTIAL FOR RED FLAG CONDITIONS ON MONDAY.
FINALLY STARTING TO SEE A FEW ECHOES ON RADAR NEAR THE SRN BORDER OF
RIO GRANDE COUNTY. OTHERWISE...ONLY SEEING A FEW CU DEVELOPING ALONG
THE ERN MTS. THE LATEST NAM RUN CONTINUES TO SHOW SOME PCPN OVR THE
MTS THIS AFTERNOON AND EVENING...AND EVEN KEEPS SOME LINGERING PCPN
OVR THE SWRN CO MTS LATE TONIGHT. THE HRRR KEEPS THE FORECAST AREA
DRY UNTIL AROUND 01Z AND THEN SHOWS A LITTLE QPF OVR THE SERN CORNER
OF THE STATE...WHICH THE GFS ALSO SHOWS. WILL KEEP ISOLD POPS
FOCUSED OVR AND NR THE SRN MTS THIS EVENING AND ENDING LATE.
ON MONDAY WESTERLY FLOW ALOFT IS EXPECTED WITH AN UPR LOW MOVING
ACRS MT DURING THE DAY AND AN UPR RIDGE OVR MEXICO. THE SFC WINDS
ARE EXPECTED TO PICK UP FOR THE AFTERNOON HOURS ACRS MUCH OF THE
FORECAST AREA FROM THE WEST OR SW AND IT LOOKS LIKE MANY AREAS COULD
SEE THE GUSTS REACH RED FLAG CRITERIA. AT THE SAME TIME...HIGH
TEMPS TOMORROW ARE EXPECTED TO BE MUCH ABOVE AVERAGE AND WITH THE
WESTERLY FLOW THE DEW POINTS WILL DRY OUT AND RH VALUES WL DROP
BELOW 15 PERCENT AT THE LOWER ELEVATIONS. THUS WENT AHEAD AND ISSUED
A RED FLAG WARNING FOR ZONES 222...225...227...233 AND 237 WHERE THE
FUELS ARE DRY AND THE WIND AND RH CRITERIA SHOULD BE MET. ZONE 221
LOOKED MARGINAL SO LEFT THEM OUT OF THE WARNING FOR NOW...BUT THIS
WILL HAVE TO BE RE-EVALUATED WITH LATER FORECAST MODEL RUNS. IN
ZONE 225 IT LOOKED LIKE THE RH AND WIND CRITERIA WOULD BE MET MAINLY
BELOW 9000 FEET.
ONE OTHER CONCERN FOR MONDAY IT WHERE THE DRY LINE WILL SET UP. THE
LATEST RUN OF THE NAM12 PUSHES THE DRY LINE WELL INTO KS MON
AFTERNOON AND SPC HAS THE SLIGHT RISK AREA JUST TO THE EAST OF THE
CO BORDER. THE NAM HAS SPOTTY PCPN ACRS THE FORECAST AREA MON
AFTERNOON AND ONCE AGAIN THE GFS SHOWS ALMOST NOTHING UNTIL
EVENING...WHEN IT TOO HAS SPOTTY QPF. ONCE AGAIN...WITH THE LOW
LEVELS BEING DRY...MEASURABLE PCPN WOULD BE SPOTTY AT BEST AND THE
MAIN THUNDERSTORMS THREATS WOULD BE WIND AND LIGHTNING.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 318 PM MDT SUN JUN 2 2013
...CHANCE OF SOME STRONG STORMS TUESDAY AND WEDNESDAY...
MAIN FOCUS IN THE EXTENDED WILL BE THE THREAT OF SVR WX RETURNING TO
THE AREA TUE AND WED. ON TUE...AN UPPER LOW WILL BE OVR THE
DAKOTAS...AND A COLD FRONT ASSOCIATED WITH THIS SYSTEM WILL BE
PUSHING THROUGH IN THE MORNING. WINDS WILL VEER TO AN UPSLOPE DIRECTION
BEHIND THE FRONT...AND SET THE STAGE FOR SCT TS DEVELOPMENT TUE
AFTERNOON INTO TUE EVE. STORMS WILL DEVELOP OVR THE ERN MTS AND THEN
SHIFT EWD BY LATE AFTERNOON. THERE WILL BE MORE THAN ENOUGH SHEAR
FOR STORM ORGANIZATION...IN THE 40 KT RANGE INCREASING TO 50 KTS OR
MORE BY EVE. MAIN LIMITING FACTOR WILL BE SOME DRY AIR IN THE LOW
LEVELS...WHICH WILL KEEP CAPE MAINLY IN THE 750-1200 J/KG RANGE.
HOWEVER...GOOD FORCING ALONG WITH PERSISTENT UPSLOPE WILL HELP BUILD
A FEW STRONG STORMS...SOME OF WHICH COULD BECOME MARGINALLY SVR AS
THEY MOVE E OF I-25 AND INTO BETTER MOISTURE LATE IN THE DAY. BEST
CHANCE FOR SVR WX WILL BE OVER THE SE PLAINS INCLUDING BACA AND
PROWERS COUNTIES...WHICH IS WHERE SPC CURRENTLY HAS THEIR SLIGHT
RISK OUTLOOK FOR DAY 3. TEMPS TUESDAY WILL BE MUCH LOWER THAN ON
MONDAY...BUT STILL FAIRLY WARM FOR THE PLAINS...IN THE MID 80S.
WEDNESDAY COULD BE A MORE ACTIVE DAY WITH SVR WX POTENTIAL...BUT IT
WILL ALSO BE A BIT TRICKY WITH THE PREVIOUS DAY`S CONVECTION
POSSIBLY HAVING AND EFFECT ON MORNING CONDITIONS...AND THE
POSSIBILITY THAT THE ATMOSPHERE MIGHT BECOME TOO STABLE TO SUPPORT
STRONG CONVECTION. EARLIER RUNS OF THE NAM HAD HINTED AT THAT
POSSIBILITY...WHILE THE LATEST NAM SEEMS TO BE ALIGNING BETTER WITH
THE GFS IN SHOWING THE POTENTIAL FOR ANOTHER ROUND OF STRONG STORMS
LATE IN THE AFTERNOON. WILL FOLLOW THIS TREND AND MAINTAIN A THREAT
OF STORMS DEVELOPING IN THE AFTERNOON WITH UPSLOPE OVR THE ERN
MTS...THEN SPREADING TO THE PLAINS LATE IN THE DAY. CAPE COULD BE A
BIT HIGHER WED...SO IF THERE IS A BIT OF SUN EARLY IN THE AFTERNOON
THIS COULD BRING THE THREAT OF SVR A LITTLE FARTHER TO THE WEST WED
AFTERNOON. WILL HAVE TO WATCH FOR THIS POTENTIAL NEXT COUPLE OF DAYS.
THE ACTIVE PATTERN LOOKS TO CONTINUE THROUGH THE END OF THE WEEK AND
POSSIBLY INTO THE WEEKEND...AS A SERIES OF WEAK SHORTWAVES ROUND THE
BACKSIDE OF THE TROUGH THAT WILL BE MOVING THROUGH THE GREAT LAKES
REGION THU-FRI. DECREASED SHEAR MAY LIMIT THE SVR THREAT...BUT WITH
SOME MOISTURE IN PLACE THE FOCUS MAY SHIFT TO THE POTENTIAL FOR SOME
LOCALLY HEAVY RAIN. NCEP MODELS INDICATE BETWEEN .25 AND .50 INCHES
OF LIQUID FOR THE WALDO SCAR TUE...ANOTHER .5 TO 1.0 INCHES
WED...AND STILL MORE PRECIP FOR THE AREA LATE THU INTO FRI. SO...THE
WALDO BURN SCAR WILL CONTINUE TO BE A TROUBLE SPOT AND WILL NEED
SOME EXTRA ATTENTION THROUGH THE END OF THE WEEK. ROSE
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 318 PM MDT SUN JUN 2 2013
VFR CONDITIONS ARE EXPECTED AT KCOS...KPUB AND KALS FOR THE NEXT 24
HOURS. WEST TO SW WINDS ARE EXPECTED TO BE BREEZY MONDAY AFTERNOON
WITH GUSTS OF 25-30 KTS AT THE TAF SITES.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM NOON TO 8 PM MDT MONDAY FOR COZ222-225-227-
233-237.
&&
$$
SHORT TERM...28
LONG TERM...ROSE
AVIATION...28
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
405 PM EDT SUN JUN 2 2013
...ISOLATED SEVERE STORMS POSSIBLE THIS EVENING...
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
COLD FRONT STILL NORTHWEST OF THE STATE HOWEVER TWO LINES OF
CONVECTION HAVE DEVELOPED ACROSS THE CWA AHEAD OF THIS FRONT. LOCAL
WRF HAS PICKED UP ON BOTH LINES BUT WEAKENS THE EASTERN LINE AND
LETS THE WESTERN LINE DOMINATE. ALTHOUGH HRRR ISNT AS CLEAR WITH
BOTH LINES...IT DOES SHOW THE WEST LINE OF CONVECTION CONTINUING TO
DOMINATE AND PUSH EAST. FORECAST IS IN LINE WITH THESE TWO HI-RES
MODELS WITH THE FOCUS BECOMING ON THE WEST LINE. WILL CONTINUE TO
MOVE EAST TONIGHT SO HAVE SHOWN CATEGORICAL POPS INTO THE EVENING
FOR MUCH OF THE CWA. WITH 1500-2000 J/KG OF MUCAPE THIS AFTERNOON
ISOLATED SVR STORMS ARE POSSIBLE WITH THE MAIN THREATS BEING WIND
AND HAIL. BEHIND THIS LINE...COULD STILL SEE SCATTERED STORMS
DEVELOP OVERNIGHT. CONFIDENCE IS LOW THOUGH ON FORECAST TONIGHT AS
THERE ARE SOME DIFFERENCES IN THE MODELS /INCLUDING HI RES/...SOME
SHOWING AN ACTIVE NIGHT WHILE OTHERS LIMITING ACTIVITY. HAVE
BASICALLY GONE CHANCE POPS THROUGH THE NIGHT.
COLD FRONT WILL PUSH THROUGH NORTH GEORGIA TONIGHT AND INTO CENTRAL
GEORGIA ON MONDAY. WILL BE ENOUGH MOISTURE AND LIFT FROM THE FRONT
THAT CONVECTION IS POSSIBLE AGAIN ON MONDAY BUT THE BETTER CHANCES
WILL BE ACROSS THE SOUTHEAST PART OF THE CWA. PLENTY OF INSTABILITY
/2000 J/KG OF MUCAPE/ MONDAY AFTERNOON TO SEE A FEW STRONG STORMS.
STORMS LOOK TO CONTINUE WITH LAST IN A SERIES OF SHORTWAVES TO
MOVE THROUGH MONDAY NIGHT. WILL INCREASE POPS TO HIGH END CHANCE
RANGE THROUGH 12Z TUESDAY AS FRONT PUSHES THROUGH.
TEMPS ARE NEAR A MODEL BLEND.
11
&&
.PREV DISCUSSION... /ISSUED 207 PM EDT SUN JUN 2 2013/
PREV DISCUSSION...
UPDATE...
/ISSUED 1025 AM EDT SUN JUN 2 2013/
SHOWERS AND THUNDERSTORMS HAVE BEEN SLOW TO DEVELOP ACROSS MUCH OF
THE CWA THIS MORNING SO MAIN CHANGE TO THE FORECAST HAS BEEN TO
REDUCE POPS FOR THE MORNING. BY EARLY AFTERNOON THOUGH...THE HRRR
INCREASES COVERAGE GREATLY ACROSS THE NORTH AND WESTERN PART OF
THE CWA AND THIS IS IN LINE WITH THE FORECAST. SOME INDICATION IN
THE MODELS SUCH AS THE GFS AND ECMWF THAT THE BETTER COVERAGE WILL
CONTINUE INTO TONIGHT AND MAY NEED TO ADJUST OUR POPS UPWARD
OVERNIGHT IN FUTURE UPDATES.
PORTIONS OF FANNIN AND GILMER COUNTY HAVE ALREADY SEEN AROUND 4
INCHES OF RAIN DURING THIS EVENT SO FAR. ALTHOUGH THEY HAVE
RECEIVED A REPRIEVE FROM THE HEAVY RAIN...WILL HAVE TO CONTINUE TO
MONITOR THIS AREA CLOSELY FOR POTENTIAL ISOLATED FLOODING AS
HEAVY RAIN IS POSSIBLE AGAIN THIS AFTERNOON.
11
PREVIOUS LONG TERM...
TUESDAY THROUGH SATURDAY/... /ISSUED 353 AM EDT SUN JUN 2 2013/ MODELS
SHOW THE COLD FRONT PUSHING INTO SOUTH GA MONDAY NIGHT... WHERE IT
MEANDERS... THEN DRIFTS BACK NORTH SLIGHTLY BY TUESDAY AFTERNOON.
THIS WILL WARRANT HOLDING ONTO A SLIGHT CHANCE OF MAINLY AFTERNOON
AND EVENING THUNDERSTORMS ACROSS THE SOUTHERN REACHES OF THE
FORECAST AREA ON TUESDAY. A SLIGHT CHANCE OF STORMS SPREAD BACK
ACROSS NORTH GA BY WEDNESDAY AS AN EASTERLY WIND FLOW BEGINS TO
ADVECT DEEP ATLANTIC MOISTURE BACK OVER THE AREA WHILE A SERIES OF
UPPER DISTURBANCES BEGIN TO CARVE A BROAD LONG WAVE TROUGH THAT
STRETCHES DOWN THE MS VALLEY REGION BY WEDNESDAY AFTERNOON. THIS
UPPER TROUGH DEEPENS OVER THE SOUTH ON THURSDAY AND PROVIDES THE
SUPPORT FOR SCATTERED SHOWERS AND THUNDERSTORMS ACROSS THE ENTIRE
FORECAST AREA THURSDAY AFTERNOON AND EVENING. AT THE SAME TIME...
THE ECMWF AND GFS SHOW AN EARLY SEASON TROPICAL SYSTEM PUSHING
INTO THE EASTERN GULF ON THURSDAY... ACROSS CENTRAL FL AND INTO
THE WESTERN ATLANTIC ON FRIDAY...THEN UP THE EAST COAST ON
SATURDAY AS HIGH PRESSURE BUILDING SOUTH OF CANADA HELPS HOLD THE
SYSTEM OFF SHORE. AHEAD OF THIS SYSTEM ON FRIDAY... A CONTINUED
MOIST EASTERLY FLOW AND UPPER TROUGH WILL SUPPORT DIURNALLY DRIVEN
AFTERNOON AND EVENING CONVECTION ACROSS THE AREA AGAIN ON FRIDAY.
AS THE TROPICAL SYSTEM PUSHES OFF TO THE NE ON SATURDAY... MODELS
SHOW A COLD FRONT AND DRIER AIR SPREADING SOUTH IN ITS WAKE. DUE
TO MUCH UNCERTAINTY ON TIMING AND TRACK... WILL CONTINUE TO SHOW A
CHANCE OF CONVECTION ON SATURDAY FOR NOW AND MONITOR CHANGES IN
THE MODEL RUNS CLOSELY OVER THE NEXT SEVERAL DAYS.
39
AVIATION...
18Z UPDATE...
CONVECTION HAS BEGUN TO DEVELOP AROUND THE TERMINALS AND FOR NOW
IS ORIENTED IN TWO LINES. EXPECT CONVECTION TO CONTINUE THROUGH
THIS EVENING BUT THEN CHANCES WILL DECREASE. HAVE KEPT SHRA IN THE
TAFS FOR MUCH OF THE NIGHT...BUT CANT COMPLETELY RULE OUT THE
CHANCE OF MORE TSRA. COULD SEE SOME GUSTY WINDS AND BRIEF LOWER
CIGS IN THE TSRA BUT SO SHORT LIVED THAT HAVENT INCLUDED IT IN
THE TAF YET EXCEPT FOR MINOR REDUCTION IN VSBY. CIGS ARE EXPECTED
TO LOWER OVERNIGHT INTO THE IFR TO LOW MVFR RANGE.
//ATL CONFIDENCE...18Z UPDATE...
MEDIUM CONFIDENCE ON TIMING OF CONVECTION...VSBYS AND CIGS. HIGH
CONFIDENCE ON WIND DIRECTION...BUT MEDIUM ON SPEEDS DUE TO
POSSIBLE GUSTS IN TSRA.
11
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 67 84 63 87 / 80 40 30 10
ATLANTA 69 84 68 86 / 80 40 10 10
BLAIRSVILLE 62 80 60 81 / 80 40 10 10
CARTERSVILLE 66 84 62 88 / 80 40 10 10
COLUMBUS 72 87 70 89 / 80 50 30 10
GAINESVILLE 67 83 65 85 / 80 40 20 10
MACON 69 86 68 90 / 80 50 40 20
ROME 67 83 61 88 / 70 30 10 10
PEACHTREE CITY 67 84 62 87 / 80 40 20 10
VIDALIA 72 86 71 89 / 60 60 40 30
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...11
LONG TERM....DEESE
AVIATION...11
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1254 PM CDT SUN JUN 2 2013
.DISCUSSION...
ISSUED 1037 AM CDT SUN JUN 2 2013
MORNING SURFACE ANALYSIS SHOWS A WEAK TROUGH AXIS EXTENDING FROM
THE GREAT LAKES S/SW INTO CENTRAL ILLINOIS. 13Z HRRR SUGGESTS
ISOLATED SHOWERS WILL DEVELOP ALONG/AHEAD OF THIS FEATURE ACROSS
THE EASTERN HALF OF THE KILX CWA LATER THIS MORNING THROUGH THE
AFTERNOON. HAVE SEEN SOME WEAK RADAR ECHOES DEVELOPING WITHIN THE
PAST COUPLE OF HOURS...SO THIS SEEMS TO BE A PLAUSIBLE SOLUTION.
WILL THEREFORE MAINTAIN THE SLIGHT CHANCE POPS ALONG AND EAST OF A
BLOOMINGTON TO EFFINGHAM LINE. SKIES WILL REMAIN CLOUDY TODAY...AS
EVIDENCED BY CURRENT VISIBLE SATELLITE IMAGERY AND STRONGLY NEGATIVE
CU-RULE. DUE TO THE CLOUDS AND A COOL NORTHWESTERLY WIND...HIGH
TEMPS WILL REMAIN WELL BELOW NORMAL FOR THIS TIME OF YEAR. HAVE
TWEAKED AFTERNOON HIGHS DOWN A FEW DEGREES...WITH READINGS MAINLY
IN THE MIDDLE TO UPPER 60S. A FEW LOWER 70S WILL BE POSSIBLE SOUTH
OF I-70. ZONE UPDATE HAS ALREADY BEEN ISSUED.
&&
.AVIATION...
ISSUED 1254 PM CDT SUN JUN 2 2013
LOW CONFIDENCE AVIATION FORECAST TODAY...DUE TO QUESTIONS
SURROUNDING TIMING OF POTENTIAL CLEARING TONIGHT. CURRENT
SATELLITE AND AREA OBSERVATIONS SHOW A WIDESPREAD BLANKET OF MVFR
CEILINGS ACROSS THE REGION...WITH CLOSEST APPRECIABLE CLEARING
LOCATED WELL TO THE NORTHWEST OVER NORTHERN IOWA. LOW-LEVEL FLOW
CONTINUES TO SLOWLY ADVECT THE CLOUD SHIELD SOUTHEASTWARD...HOWEVER
WINDS ARE EXPECTED TO BECOME LIGHT/VARIABLE OVERNIGHT...SLOWING
THE EXIT OF THE CLOUDS. BOTH NAM AND GFS FORECAST SOUNDINGS HANG
ON TO A SATURATED LAYER BETWEEN 2500 AND 3500FT THROUGH MONDAY
MORNING...SUGGESTING CLOUDS MAY HOLD FIRM THROUGH THE NIGHT.
MEANWHILE...HRRR CEILING FORECAST SHOWS CLOUDS DISSIPATING AT THE
TAF SITES...BUT REMAINING IN PLACE FURTHER SOUTH ACROSS THE S/SE
KILX CWA AS WINDS BECOME LIGHT AND/OR VEER TO E/NE. GIVEN HRRR
FORECAST AND THE APPEARANCE THAT MUCH OF THE UPSTREAM CLOUD COVER
ACROSS IOWA IS DIURNAL/CELLULAR...HAVE SCATTERED CEILINGS AT
THE CENTRAL ILLINOIS TERMINALS BETWEEN 03Z AND 06Z. IF PARTIAL
CLEARING DOES INDEED OCCUR TONIGHT...IT WILL SHORT-LIVED...AS
HIGHLY NEGATIVE CU-RULE SUGGESTS BKN CEILINGS DEVELOPING AGAIN BY
LATE MONDAY MORNING THROUGH THE AFTERNOON.
BARNES
&&
.PREV DISCUSSION...
ISSUED 225 AM CDT SUN JUN 2 2013
COLD FRONT HAS PUSHED WELL TO THE EAST EARLY THIS MORNING. 2 AM
SURFACE MAP SHOWS A SECONDARY TROUGH SWINGING ACROSS THE NORTHWEST
PART OF ILLINOIS...AROUND LOW PRESSURE IN NORTHEAST LOWER
MICHIGAN. EXTENSIVE STRATOCUMULUS IS FOUND ALONG AND BEHIND THIS
TROUGH...WHILE SKIES HAVE BEEN CLEAR OVER THE EASTERN CWA THE PAST
FEW HOURS BETWEEN THE TROUGH AND FRONT.
THE MAIN FORECAST ISSUE FOR THIS PACKAGE INVOLVES MID WEEK RAIN
CHANCES.
SHORT TERM...TODAY THROUGH TUESDAY...
HAVE MAINTAINED SOME 20 PERCENT RAIN CHANCES ACROSS THE EASTERN
CWA TODAY AS THE TROUGH SWINGS THROUGH...BUT QUIET WEATHER WILL
GENERALLY PREVAIL THROUGH TUESDAY. 850 MB TEMPS FALLING INTO THE
LOW SINGLE DIGITS CELSIUS TONIGHT SHOULD ALLOW FOR SURFACE LOWS IN
THE UPPER 40S OVER ABOUT THE NORTHEAST HALF OF THE CWA...WITH
HIGHS IN THE UPPER 60S TO AROUND 70. AS SURFACE HIGH PRESSURE
SHIFTS EASTWARD ACROSS THE GREAT LAKES MONDAY NIGHT...DECENT WARM
AIR ADVECTION WILL OVERSPREAD THE CWA AND BRING HIGHS WELL INTO
THE 70S.
LONG TERM...TUESDAY NIGHT THROUGH SATURDAY...
EVENING MODEL GUIDANCE IN REASONABLE AGREEMENT WITH ZIPPING AN
UPPER TROUGH THROUGH THE NORTHERN AND CENTRAL PLAINS ON
TUESDAY...ASSOCIATED WITH A CLOSED SURFACE LOW CLOSER TO THE
CANADIAN BORDER. NOT TOO MUCH CHANGE NOTED WITH TRENDS OF
SPREADING RAIN CHANCES INTO AREAS WEST OF I-55 BY LATE TUESDAY
NIGHT. RATHER PERSISTENT EASTERLY FLOW ACROSS THE GREAT LAKES DOES
NOT BODE VERY WELL FOR DECENT PRECIP CHANCES IN THE EAST...AND
WILL GO WITH SLIGHT CHANCES THERE ON WEDNESDAY. MAIN TROUGH AXIS
SHOULD CROSS THE AREA LATE WEDNESDAY NIGHT THROUGH THURSDAY...
WHEN HIGHEST POPS OF 40 TO 50 PERCENT WILL BE IN THE FORECAST.
LATE IN THE WEEK...HAVE MAINTAINED SOME SLIGHT CHANCES FOR
FRIDAY. HOWEVER...GENERAL TREND SHOULD BE FOR DRY WEATHER INTO THE
FIRST HALF OF THE WEEKEND...WITH HIGH PRESSURE RIDGING SOUTHWEST
FROM THE GREAT LAKES.
GEELHART
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 7 PM CDT THIS EVENING FOR ILZ051.
&&
$$
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
1158 AM CDT SUN JUN 2 2013
.AVIATION...
MUCH OF THE ORGANIZED CONVECTION HAS MOVED OFF THE LOUISIANA COAST
LATE THIS MORNING WITH SOME LINGERING ANVIL RAINS AND ELEVATED
CONVECTION INLAND BETWEEN THE COAST AND KMSY/KNEW. THIS ACTIVITY
WAS DRIVEN BY MESO-HIGH FORCING WITH THE ACTUAL COLD FRONT STILL
ORIENTED NE-SW FROM PADUCAH KY TO ABOUT JACKSON MS TO BEAUMONT TX.
ISOLATED SHRA/TSRA CAN NOT BE RULED OUT ALONG THE FRONT LATER THIS
AFTERNOON BUT COVERAGE SHOULD REMAIN LIGHT. VFR CLOUD DECKS SHOULD
ALSO THIN TO VFR CAVOK LATE AFTERNOON. 24/RR
&&
.DECISION SUPPORT...
DSS CODE...BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT.
MONITORING RIVER FLOODING.
MONITORING CONVECTIVE TRENDS.
&&
.PREV DISCUSSION... /ISSUED 1017 AM CDT SUN JUN 2 2013/
UPDATE...
LOOKING AT OVERALL RADAR TRENDS...HAVE ADJUSTED POPS FOR TODAY TO
REFLECT THE ONGOING CONVECTION OVER COASTAL LOUISIANA AND THE WEAK
MESOHIGH IN THE WAKE OF THE EARLY MORNING CONVECTION OVER THE
REMAINDER OF THE CWA. HAVE ALSO ADJUSTED CLOUD COVER TO REFLECT
OVERALL HIGHER AMOUNT OF SKY COVER THAN INITALLY ANTICIPATED. THE
RAIN COOLED STABLE AIRMASS COMBINED WITH THE CLOUD COVER HAS ALSO
ALLOWED FOR SLOWLY TEMPERATURE RECOVERY AND ADJUSTED DAYTIME HIGHS
DOWNWARD A FEW DEGREES. EXPECT TO SEE SOME RECOVERY THIS AFTERNOON
OF WARMTH AND MOISTURE WHICH WILL ALLOW FOR SOME REGENERATION IN
AREAS NOT COMPLETELY WORKED OVER THIS MORNING. GIVEN THIS...KEEP
LIKELY POPS IN PLACE FOR COASTAL LOUISIANA AND MISSISSIPPI...AND
ONLY HAVE CHANCE POPS ELSEWHERE. STILL EXPECT ACTUAL FRONTAL
PASSAGE TONIGHT...WITH A DRIER WEATHER REGIME TAKING HOLD FOR MUCH
OF THE WEEK. 32
PREV DISCUSSION... /ISSUED 415 AM CDT SUN JUN 2 2013/
SHORT TERM...
MOST ACTIVE PORTION OF THE FORECAST WILL BE OVER THE NEXT 12 TO 15
HOURS. SURFACE ANALYSIS SHOWS COLD FRONT DRAPED ACROSS SOUTH-CENTRAL
TEXAS...NORTHERN LA THROUGH EASTERN ARKANSAS AND POINTS FURTHER
NORTH. A LARGE CLUSTER OF SHOWERS AND EMBEDDED STRONGER
THUNDERSTORMS AHEAD OF THE FRONT HAS BEEN SURGING SOUTHWARD
OVERNIGHT. AT THIS POINT...THIS ACTIVITY HAS BECOME OUTFLOW DRIVEN
VS THE MEAN FLOW WHICH WOULD BE MORE EASTERLY. HRRR SEEMS TO BE THE
ONLY MESO MODEL THAT HAS BEEN HAVING A GOOD INITIATION. IT SUGGESTS
A WEAKENING TREND WILL CONTINUE AS THE LEADING EDGE MOVES SOUTH
ACROSS MS AND LA TOWARDS THE CWA. WHILE IN GENERAL THIS WILL LIKELY
BE THE CASE...THERE/S STILL SOME INSTABILITY IN PLACE OVER THE AREA
WHICH WILL ALLOW A FEW CELLS TO BURST UP TO STRONG CATEGORY WITH
STRONG GUSTY WINDS.
HAVE SLIGHTLY BUMPED UP POPS TODAY...MAINLY TO ACCOUNT FOR ACTIVITY
THAT SHOULD BE GOING ON THIS MORNING. AFTER IT DISSIPATES...
DEVELOPMENT OF AFTERNOON SHOWERS AND A FEW THUNDERSTORMS WILL STILL
BE POSSIBLE AS INSTABILITY REMAINS IN PLACE.
COLD FRONT WILL STILL BE PUSHING SOUTH THROUGHOUT THE NIGHT AND
SHOULD BE REACHING THE COAST BY 12Z MONDAY. HAVE TRIMMED POPS
FURTHER SOUTH FOR THE MORNING PERIOD SO THAT ONLY COASTAL PARISHES
AND OFFSHORE WATERS HAVE WORDING OF RAIN IN THE ZONES.
LONG TERM...
WEAK UPPER LEVEL RIDGING WILL BUILD INTO THE AREA MID WEAK AS UPPER
TROUGH EJECTS. SUBSEQUENTLY...RAIN CHANCES WILL DROP OFF MONDAY
AFTERNOON THROUGH WEDNESDAY. IN ADDITION...DAYTIME HIGHS WILL BE ON
THE RISE AS HEIGHTS INCREASE. TEMPS SHOULD MAKE IT TO THE 90 TO 93
DEGREE MARK FAIRLY EASILY.
AN UPPER TROUGH WILL TRACK ACROSS THE UPPER MISSISSIPPI VALLEY IN
THE LATTER PORTION OF THIS WEEK. THIS WILL BREAKDOWN THE EAST SIDE
OF UPPER RIDGE OVER THE GULF COAST THUS ALLOWING FOR AFTERNOON
SHOWERS AND THUNDERSTORMS TO BEGIN DEVELOPING AGAIN.
MEFFER
AS HAS BEEN THE CASE FOR SEVERAL NIGHTS...THE OVERNIGHT AVIATION
PROBLEM WILL BE THE DEVELOPMENT OF LOW CLOUDS. SEEING SOME
DEVELOPMENT IN THE FL015-FL025 RANGE...MOST NOTABLY AT KHUM...AT
THIS TIME. EXPECT SCT-BKN CLOUDS TO BECOME WIDESPREAD ACROSS THE
AREA BY 09Z AND REMAIN THROUGH ABOUT 15Z. ONE OR TWO SITES WILL
LIKELY FALL INTO THE IFR RANGE...PROBABLY AT KMCB.
THE OTHER PROBLEM WILL BE THE TIMING OF CONVECTION ASSOCIATED
WITH THE FRONTAL BOUNDARY. CURRENT MOVEMENT APPEARS TO BE ABOUT
340/17 KTS. THIS WILL ALLOW CONVECTION TO REACH KMCB AND KBTR
SOMETIME AROUND SUNRISE...ALTHOUGH A STRAY SHOWER OR TWO COULD REACH
KMCB BEFORE THEN. EXPECT A WEAKENING TREND FROM WHAT IS BEING
OBSERVED AT THIS TIME. WILL LEAD INTO EVENT WITH MENTION OF
VCSH/VCTS AND CARRY ABOUT A 4 HOUR WINDOW WITH THE MAIN CONVECTION.
FOR NOW...WILL ONLY USE TEMPO GROUPS AT KMCB...KBTR AND KHDC. WILL
ADJUST LATER AS WE CAN BETTER ANTICIPATE TIMING AT TERMINALS FARTHER
SOUTH AND EAST. STILL NOT CONFIDENT ON EXACTLY HOW FAR SOUTHWARD
FRONT WILL MAKE IT ON SUNDAY BEFORE RUNNING OUT OF PUSH. WIND FIELD
WILL LIKELY BECOME RATHER WEAK TOWARD EVENING.
35
MARINE...
WIND FIELD IS CONSIDERABLY WEAKER THIS MORNING THAN IT HAS BEEN FOR
SEVERAL DAYS. WITH A WEAKENING COLD FRONT ANTICIPATED TO MOVE INTO
THE AREA TODAY...WIND FIELDS WILL BECOME EVEN LIGHTER. WIND
DIRECTIONS WILL BE RATHER VARIABLE...BUT GENERALLY WITH AN EASTERLY
COMPONENT. NOT EXPECTING WINDS TO BE MUCH ABOVE 10 KNOTS BEFORE
THURSDAY...WITH THE POSSIBLE EXCEPTION OF THE USUAL EVENING DIURNAL
MAXIMUM. EVEN THEN...DO NOT ANTICIPATE WINDS STRONG ENOUGH TO
REQUIRE HEADLINES. 35
DECISION SUPPORT...
DSS CODE...BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT.
MONITORING RIVER FLOODING.
MONITORING CONVECTIVE TRENDS.
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED
WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE TO HIGH RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 81 66 88 63 / 50 20 10 10
BTR 82 68 89 67 / 50 20 10 10
ASD 83 70 90 69 / 70 30 10 10
MSY 82 73 89 72 / 70 30 10 10
GPT 84 71 89 69 / 70 30 10 10
PQL 86 71 88 68 / 70 30 10 10
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
135 PM EDT SUN JUN 2 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 520 AM EDT SUN JUN 2 2013
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM
NW ONTARIO INTO THE CNTRL GREAT LAKES. A SHORTWAVE SUPPORTING OVER
NRN LAKE MICHIGAN INTO NW LOWER MI SUPPORTED AN AREA OF RAIN OVER
ERN UPPER MI THAT WAS SLOWLY SLIDING OFF TO THE EAST. SCT LIGHT
SHOWERS ALSO LINGERED OVER CNTRL UPPER MI. AT THE SFC...A TIGHT
GRADIENT BETWEEN LOW PRES OVER LAKE HURON AND A RIDGE INTO THE NRN
PLAINS SUPPORTED BRISK NRLY WINDS ACROSS LAKE SUPERIOR INTO THE
UPPER MI. UPSLOPE NRLY FLOW INTO THE HIGHER TERRAIN ALSO SUPPORTED
AREAS OF DRIZZLE. MUCH COLDER AIR HAS MOVED INTO THE REGION WITH
TEMPS DROPPING INTO THE UPPER 30S AND LOWER 40S.
TODAY...ALTHOUGH THE NAM AND HIGH RES MODELS SHOW LOW LEVEL
DRYING WILL SPREAD THROUGH MOST OF THE CWA THIS MORNING...UPSTREAM
CLOUDS TRENDS SUGGEST THAT THE CLEARING TREND MAY BE SLOWER. ANY
LINGERING LIGHT SHOWERS OR DRIZZLE SHOULD END BY MID OR LATE MORNING
WITH CLEARING FROM WEST TO EAST BY EARLY TO MID AFTERNOON. EVEN WITH
SUNSHINE...WITH N FLOW ACROSS LAKE SUPERIOR AND 850 MB TEMPS NEAR
-1C...TEMPS WILL STRUGGLE INTO THE UPPER 40S TO LOWER 50S NORTH AND
INTO THE MID AND UPPER 50S SOUTH.
TONIGHT...SFC HIGH PRES BUILDING INTO THE REGION FROM THE WEST
SUNDAY NIGHT WILL RESULT IN IDEAL RADIATIONAL COOLING CONDITIONS
OVER THE WESTERN INTERIOR OF THE CWA WHERE MIN TEMPS WILL LIKELY
FALL INTO LOWER 30S...NEAR THE LOWER END OF GUIDANCE.
SOME TRADITIONAL COLD SPOTS COULD ALSO SEE READINGS INTO THE UPPER
20S. SO...A FROST ADVISORY WAS ISSUED FOR INLAND PORTIONS OF THE WEST
HALF OF UPPER MICHIGAN. A VORTEX DESCENDING FROM NRN ONTARIO IS
EXPECTED TO GRAZE NE LAKE SUPERIOR. ALTHOUGH PCPN AND CLOUDS WITH
THIS FEATURE ARE EXPECTED TO REMAIN THE NE OF THE CWA...THE VORTEX
WILL RESULT IN NW WINDS STRONG ENOUGH TO MAINTAIN SOME BOUNDARY LAYER
MIXING AND PREVENT TEMPS FROM DROPPING OFF AS FAR AS IN THE WEST.
LOOK FOR MAINLY MID TO UPPER 30S MIN TEMPS OVER THE EAST HALF.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 343 AM EDT SUN JUN 2 2013
UPPER TROUGH THAT IS CURRENTLY AFFECTING THE UPPER GREAT LAKES
EARLY THIS MORNING WILL BE SHIFTING EAST THROUGH EASTERN CANADA ON
MONDAY. THIS WILL LEAD TO THE AREA BEING UNDER NORTHWEST FLOW ALOFT
AND A SURFACE HIGH PRESSURE RIDGE FROM A HIGH CENTERED IN SOUTH
CENTRAL CANADA. WITH DRY LOW AND MID LEVELS UNDER THE HIGH PRESSURE
RIDGE...EXPECT A MOSTLY SUNNY SKY ACROSS MUCH OF THE LAND AREA.
THERE COULD BE SOME LINGERING CLOUDS OVER NORTHEAST LAKE SUPERIOR
AND FAR EASTERN UPPER MICHIGAN AS THE UPPER TROUGH DEPARTS. WITH
THE SUNSHINE...EXPECT MIXING TO AROUND 850-825MB. BUT WITH
TEMPERATURES AT THAT LEVEL ONLY AROUND 2C WEST AND -1C EAST...BELOW
NORMAL HIGHS ARE EXPECTED AND ONLY IN THE 50S AND LOWER 60S. THE
COOLEST TEMPERATURES WILL BE ALONG THE GREAT LAKES SHORELINES DUE
TO LAKE BREEZES. THE OTHER ITEM TO MENTION FOR MONDAY WILL BE LOW
RH VALUES. ML DEWPOINTS FROM THE MODELS INDICATE VALUES IN THE MID
20S OVER THE INTERIOR LOCATIONS AND POTENTIALLY THE UPPER TEENS IF
THE GFS IS CORRECT. WITH THAT CONSISTENCY AND THE TRENDS IN THE
MAV/MET...HAVE LOWERED OUR DEWPOINTS A GOOD 5-7 DEGREES. THIS
PRODUCES RH VALUES OF 25-35 PERCENT OVER THE INLAND AREAS...WITH
THE LOWEST VALUES OVER THE WEST. FORTUNATELY...THE WET WEATHER
RECENTLY...GREEN UP WELL ON IT/S WAY OR EVEN DONE...AND BELOW NORMAL
TEMPERATURES REDUCES FIRE WEATHER CONCERNS EVEN WITH 10-15KT WINDS.
THE HIGH PRESSURE RIDGE WILL STILL BE OVER THE AREA ON MONDAY NIGHT
AS AN UPPER RIDGE SLIDES ACROSS THE AREA. THE CLEAR SKIES...LIGHT
WINDS...AND PWAT VALUES AROUND 30-40 PERCENT OF NORMAL WILL LEAD TO
A COLD NIGHT ACROSS THE AREA. WILL CONTINUE THE TREND OF GOING
BELOW GUIDANCE VALUES AND HAVE LOWS AROUND 30 OVER THE INTERIOR
LOCATIONS. RECORD LOWS FOR JUNE 4 ARE IN THE MID-UPPER 20S...SO
WE WILL BE CLOSE BUT LIKELY STAY ABOVE THE RECORD LOWS. WILL ALSO
CONTINUE THE MENTION OF FROST FOR MONDAY NIGHT ALONG WITH
HIGHLIGHTING IN HWO.
AREA WILL STILL BE UNDER THE INFLUENCE OF THE HIGH ON TUESDAY...AS
IT DRIFTS SOUTHEAST ACROSS THE CWA THROUGH THE DAY. THIS WILL LEAD
TO LIGHTER WINDS ACROSS THE AREA. DO EXPECT TO SEE SOME HIGH
CLOUDS STREAMING EAST ACROSS THE WESTERN CWA DURING THE
AFTERNOON AHEAD OF THE NEXT SYSTEM APPROACHING THE AREA. HIGHS WILL
BE A LITTLE WARMER ON TUESDAY...AS 850MB TEMPS WARM A COUPLE DEGREES
FROM MONDAY. WITH THE RIDGE LINGERING OVER THE EAST...HAVE LOWERED
TD VALUES SIGNIFICANTLY OVER THE EAST HALF. THIS WILL LIKELY LEAD TO
ANOTHER LOW RH DAY...BUT AS WITH MONDAY...FIRE WX CONCERNS ARE
LIMITED WITH EVEN LIGHTER WINDS.
THE UPPER TROUGH CURRENTLY OVER BRITISH COLUMBIA WILL BE MOVING
THROUGH THE NORTHERN PLAINS ON TUESDAY AND THEN BECOME CLOSE ENOUGH
TO START INFLUENCING THE UPPER GREAT LAKES FOR TUESDAY NIGHT AND
CONTINUING INTO THURSDAY. THERE ARE STILL QUESTIONS ON THE EXACT
TRACK OF THE SHORTWAVE TROUGH...WHICH IN TURN AFFECTS THE LOCATION
OF THE SURFACE LOW AND RESULTANT WARM AIR ADVECTION PRECIPITATION.
LATEST IDEA FROM THE GFS/ECMWF IS THAT MUCH OF THE INITIAL
PRECIPITATION WILL BE WEST OF THE AREA TUESDAY EVENING AND THEN
SLIDE OVER THE AREA TUESDAY NIGHT AND CONTINUE INTO WEDNESDAY NIGHT
AS THE SURFACE LOW/TROUGH SLIDES FROM THE DAKOTAS INTO SOUTHWEST
WISCONSIN. THE WARM AIR ADVECTION IS FAIRLY BROAD AND WEAK...SO
WOULD EXPECT THE PRECIPITATION TO BE GENERAL LIGHT SHOWERS. WITH
THE BEST FORCING FOCUSED OVER WISCONSIN AND THE SOUTHERN HALF OF THE
CWA...HAVE THE HIGHEST POPS IN THAT AREA. SINCE THE BULK OF THE
FORCING IS SOUTH OF THE AREA...WILL KEEP POPS IN THE HIGH CHANCE
CATEGORY SINCE IT IS ENTIRELY POSSIBLE MUCH OF THE RAIN STAYS IN
WISCONSIN. THUNDER CHANCES ARE LIMITED TO NON-EXISTANT...AS
SHOWALTER VALUES ARE WELL ABOVE ZERO AND MUCAPE VALUES STAY BELOW
100 J/KG DURING THIS PERIOD.
EXPECT A DIMINISHING TREND IN THE PRECIPITATION FOR THURSDAY INTO
THURSDAY NIGHT...AS THE DISTURBANCE SHIFTS EAST AND HIGH PRESSURE
NEAR HUDSON BAY PUSHES DRIER AIR INTO THE AREA. THIS SHOULD LEAD TO
DRY WEATHER FOR FRIDAY...BUT ANOTHER WEAK SHORTWAVE TRIES TO SLIDE
EAST ACROSS THE AREA FOR SATURDAY. WITH THE DRY EASTERLY FLOW AND
THE POTENTIAL THE HIGH REMAINS IN PLACE...IT/S ARRIVAL MAY BE
DELAYED SOME. TEMPERATURES FROM MID WEEK ON WILL CONTINUE THE BELOW
NORMAL TREND...WITH HIGHS GENERALLY IN THE 50S-60S AND THE COOLEST
DAY ON WEDNESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 134 PM EDT SUN JUN 2 2013
GUSTY NNW WINDS WILL SLOWLY DIMINISH THROUGH THE REMAINDER OF THE
AFTERNOON HOURS...AND FALLING TO AROUND 8KTS OR LESS OVERNIGHT
/STRONGEST AT CMX/. EXCLUDING INITIALLY AT SAW...VFR CEILINGS AND
VIS WILL BE THE RULE THROUGH MONDAY...WITH ANOTHER ROUND OF
INCREASED NW WINDS WITH GUSTS IN THE TEENS SHORTLY AFTER DAYBREAK
MONDAY.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 520 AM EDT SUN JUN 2 2013
LOW PRESSURE OVER GEORGIAN BAY WILL SHIFT ENE INTO QUEBEC BY THIS
AFTERNOON...WHILE A RIDGE OF HIGH PRESSURE BUILDS OVER NORTHERN
ONTARIO. AS A RESULT...NORTH WINDS WILL DIMINISH TODAY. RIDGING WILL
EXTEND OVER LAKE SUPERIOR TONIGHT...WHICH WILL REMAIN THROUGH MUCH
WEDNESDAY AS THE NEXT LOW WILL SLIDES ACROSS THE NORTHERN PLAINS.
THE LOW WILL SHIFT SLOWLY E INTO THE MID MS VALLEY THURSDAY...WHILE
THE WEAK RIDGE OF HIGH PRESSURE LINGERS OVER LAKE SUPERIOR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
FROST ADVISORY FROM 2 AM EDT /1 AM CDT/ TO 8 AM EDT /7 AM CDT/
MONDAY FOR MIZ002-004-005-009>011-084.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...KF
MARINE...JLB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
120 PM CDT SUN JUN 2 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 342 AM CDT SUN JUN 2 2013
EARLY MORNING SURFACE ANALYSIS REVEALED A BROAD
RIDGE OF HIGH PRESSURE ACROSS THE DAKOTAS. THIS HIGH WAS LOCATED
BENEATH AN UPPER LEVEL RIDGE LOCATED JUST UPSTREAM OVER EASTERN
MONTANA. OVER THE NEXT 24 HOURS THIS HIGH WILL SLOWLY MIGRATE
EASTWARD BRINGING SOME MUCH ANTICIPATED DRY WEATHER.
HOWEVER...AFTERNOON TEMPERATURES WILL REMAIN COOL AS H850 TEMPS
LINGER IN THE 2 TO 4C RANGE. BOTH THE RAP AND NAM BUFR SOUNDINGS
SHOW MIXING UP TO AROUND 800MB WITH SATURATION AT THE TOP OF THE
BOUNDARY LAYER. THEREFORE USED THE MIXDOWN TOOL FOR HIGH
TEMPERATURES THIS AFTERNOON. ALSO INCLUDED SOME AFTERNOON CLOUDS
ACROSS THE SOUTHEASTERN HALF OF THE FORECAST AREA IN ANTICIPATION OF
SOME FLAT CU DURING PEAK HEATING. THESE CLOUDS WILL QUICKLY
DISSIPATE AFTER SUNSET SETTING THE STAGE FOR RADIATIONAL COOLING AND
ANOTHER CHILLY NIGHT ACROSS THE REGION.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 342 AM CDT SUN JUN 2 2013
NORTHWEST UPPER FLOW WILL PREDOMINATE THROUGH THE PERIOD... KEEPING
THINGS A BIT COOL ACROSS OUR AREA WITH NO REAL SEVERE WEATHER
CONCERNS. THERE ARE CERTAINLY SOME DIFFERENCES IN THE DETAILS
BETWEEN THE ECMWF AND GFS AND THEIR RESPECTIVE ENSEMBLES... BUT IN
GENERAL THERE IS GOOD AGREEMENT ON THE EVOLUTION OF THE LARGE
SCALE PATTERN THROUGH THE WEEK. ONE UPPER WAVE WILL SLOWLY MIGRATE
ACROSS THE AREA TUESDAY AND WEDNESDAY... WITH WEAK RIDGING FOR
THURSDAY INTO EARLY FRIDAY... THEN AN UPPER WAVE WILL SLOWLY WORK
IN FROM THE NORTHERN PLAINS AS WE MOVE INTO THE UPCOMING WEEKEND.
ALLOWED FOR SOME LOW POPS TO WORK INTO THE WESTERN PART OF THE
FORECAST AREA ON MONDAY AS WE GET ON THE BACKSIDE OF THE SURFACE
RIDGE AND START TO SEE SOME WARM ADVECTION DEVELOP OVER THE
WESTERN PART OF THE AREA. CHANCES FOR PCPN WILL THEN SPREAD
EASTWARD MONDAY NIGHT THROUGH TUESDAY AS A SURFACE LOW NEAR THE
NORTHERN END OF AN INVERTED TROUGH WORKS ITS WAY FROM THE DAKOTAS
ACROSS MICHIGAN. A LOOK AT 850-500MB DIFFERENTIAL THETA-E AND BEST
LIFTED INDICES SHOWS ELEVATED INSTABILITY SLIGHTLY LAGGING THE
INITIAL WARM ADVECTION AND MOISTURE RETURN... SO SHOULD SEE SHOWER
CHANCES AT FIRST GIVE WAY TO THE CHANCE FOR SHOWERS WILL SOME
EMBEDDED THUNDER. SEVERE WEATHER THREAT LOOKS LOW THROUGH THE WEEK
GIVEN GENERALLY MEAGER INSTABILITY UP INTO OUR AREA... WITH THE
MAIN BAROCLINIC ZONE REMAINING WELL TO THE SOUTH. HOWEVER... THERE
IS VERY STRONG DEEP LAYER SHEAR MIGRATING ACROSS ON TUESDAY AHEAD
OF THE AFOREMENTIONED SURFACE LOW... SO SHOULD INSTABILITY MANAGE
TO BE BETTER THAN THE FEW HUNDRED J/KG ADVERTISED BY THE NAM AND
GFS THEN THERE COULD BE SOME CONCERNS. HOWEVER... THE BETTER
SHEAR... BOTH LOW-LEVEL AND DEEP LAYER... LOOKS LIKE IT WILL
OUTPACE WHERE THE BETTER INSTABILITY WILL OCCUR ON TUESDAY...
WHICH SHOULD FURTHER MITIGATE ANY POTENTIAL. MAIN CONCERN IF
INSTABILITY WERE CLOSER TO 500 J/KG AND BETTER ALIGNED WITH SHEAR
WOULD BE LOW-TOPPED SUPERCELL POTENTIAL... BUT AT THIS POINT
THINGS DON/T APPEAR TO BE COMING TOGETHER TOO WELL FOR THAT.
PCPN CHANCES WILL LINGER ACROSS THE AREA TUESDAY NIGHT INTO
WEDNESDAY AS THE UPPER WAVE AND FILLING SURFACE LOW SLIDE ACROSS
THE AREA. A BIT OF A BACKDOOR COLD FRONT AND RIDGE OF HIGH
PRESSURE WILL WORK INTO THE AREA THURSDAY INTO FRIDAY... WHICH
SHOULD BRIEFLY REDUCE CHANCES FOR ANY PCPN OVER THE AREA.
HOWEVER... GIVEN THE ADVERTISED COOL 700-500MB TEMPERATURES AND
POTENTIAL FOR DECENT LAPSE RATES WITH ANY SUNSHINE... WE COULD
CERTAINLY WIND UP WITH SOME SHRA IF THERE ISN/T SUFFICIENT RIDGING
AND LOW LEVEL SUBSIDENCE. SO... WENT WITH LOWER OR NO POPS
THURSDAY AND FRIDAY FARTHER NORTH WHERE RIDGING LOOKS LIKE IT
SHOULD BE MORE PREVALENT... BUT KEPT SLIGHTLY HIGHER CHANCES
FARTHER SOUTH. DIDN/T INCLUDE ANYTHING FOR THURSDAY NIGHT... SINCE
IT SEEMS ANY POTENTIAL WOULD BE DIURNALLY DRIVEN. BY SATURDAY...
WE MAY SEE CHANCES FOR MORE WIDESPREAD PCPN START TO WORK IN FROM
THE WEST AS WE ONCE AGAIN GET ONTO THE BACKSIDE OF THE SURFACE
HIGH AND START TO SEE SOME WARM ADVECTION AND MOISTURE RETURN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1251 PM CDT SUN JUN 2 2013
LARGE AREA OF LOW VFR STRATO-CU NOTED OVER PORTION OF WEST
CENTRAL WI AND OVER LARGE SECTION OF WEST CENTRAL MN. EXPECT
BOTH AREAS TO MOSTLY DISINTEGRATE BY 00Z AS HEATING WANES.
MODERATE NW FLOW WILL ALSO FADE BY THE EARLY EVENING AT ALL
SITES. SURFACE RIDGE WILL CONTINUE ACROSS THE ENTIRE REGION INTO
MON/12Z TIME FRAME. NEW STORM SYSTEM WILL BEGIN TO ENTER WESTERN
SODAK THIS TIME FRAME...AND THEN TREK INTO WESTERN NE BY 04/00Z.
CIRRUS SHIELD WILL OVERSPREAD MOST AIRPORT SITES BY EARLY MONDAY
AFTERNOON...AS WARM FRONTAL BOUNDARY OVER WEST CENTRAL AND
SOUTHWEST MN GENERATES SCT -SHRA NEAR KAXN BY 05/00Z. LIGHT SE
FLOW WILL BE ENCOUNTERED OVER SOUTHERN MN MONDAY
MORNING...INCREASING AS SURFACE GRADIENT INCREASES AHEAD OF STORM
SYSTEM DURING THE AFTN. WEST CENTRAL TAF SITES WINDS WILL BE LIGHT
AND VRBL BECOMING LIGHT SE BY END OF PERIOD. VFR CIGS AND VSBYS
THROUGH END OF PERIOD ALL LOCATIONS.
KMSP...
HEATING INDUCED STRATO-CU DECK COULD BECOME BKN BETWEEN 19-22Z
...WITH FAIRLY RAPID BREAKUP ANTICIPATED BY 23Z. MDT SE FLOW
BECOMES LIGHT BY LATE AFTN AND RETURNS BY 03/16Z. MID LEVEL
CLOUD DECK AHEAD OF APPROACHING CYCLONE MENTIONED ABOVE WILL
BE ENCOUNTERED LATE IN PERIOD. VFR CIGS AND VSBYS THROUGH
END OF PERIOD. LIGHT SHOWER VCNTY POSSIBLE NEAR 04/06Z.
/OUTLOOK FOR KMSP/
MON...VFR WITH -SHRA LATE. WINDS SE AT 10KTS.
TUE...MVFR WITH -SHRA/TSRA LIKELY. WINDS ESE AT 10G20KTS.
WED...VFR WITH MVFR/TSRA POSSIBLE. WINDS NNE AT 10KTS.
THU...VFR WITH MVFR/ISOLATED TSRA POSSIBLE. WIND E 6-10KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...JRB
LONG TERM...
AVIATION...AJZ
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1238 PM CDT SUN JUN 2 2013
.AVIATION...
18Z TAFS FOR KOMA...KLNK AND KOFK.
CIGS FL040 ALONG THE MISSOURI RIVER WILL CONTINUE TO SHIFT EAST
OUT OF THE AREA. VFR CONDITIONS ARE EXPECTED TO
CONTINUE...HOWEVER WILL NEED TO MONITOR LOW LEVEL MOISTURE.
RAP/NAM ARE HINTING THAT AS WEAK FLOW BECOMES SOUTHEAST...SOME OF
THAT MOISTURE WILL TRY TO RETURN AND A BAND OF STRATUS COULD
DEVELOP. AFTER 12Z...SOUTHEAST SURFACE WINDS WILL BEGIN TO RAMP
UP TO 10 TO 20 KTS AND GUSTY BY LATE MONDAY MORNING.
&&
.PREV DISCUSSION... /ISSUED 302 AM CDT SUN JUN 2 2013/
DISCUSSION...
MAIN FORECAST CHALLENGE WAS WHEN TO INCLUDE TSTM CHANCES AS
ANOTHER UPPER TROUGH/LOW MOVES FROM SWRN CANADA ACROSS NORTHERN
PLAINS THROUGH MIDWEEK.
FOR TODAY...UPPER RIDGE AHEAD OF SWRN CANADIAN LOW TO FLATTEN AS
IT BUILDS ACROSS CNTRL PLAINS AS UPPER LOW SOUTH OF HUDSONS BAY
DROPS SOUTH. PERSISTENT LOW CLOUDS HAVE CLEARED WRN ZONES AS OF
730Z AND SHOULD CONTINUE TO DO SO THROUGH THIS MORNING...ALTHOUGH
LATEST RAP SOUNDING DELAYED THIS CLEARING ALONG/E OF MO RIVER TILL
AFTERNOON. SLOWED CLEARING DOWN A BIT E...AND FURTHER ADJUSTMENTS
MAY BE NEEDED. MILDER TEMPS COMPARED TO SATURDAY BUT STILL BELOW
NORMAL AND GENERALLY A DEG OR TWO BELOW GUIDANCE BASED ON PERHAPS
HINDERED MIXING FROM MORNING/EARLY AFTN CLOUDS E AND/OR SLIGHTLY
COOLER H85 TEMPS PER 00Z ECMWF.
UPPER LOW MOVING TOWARD DAKOTAS LATE MONDAY WILL STRENGTHEN LOW
LEVEL JET LATE TONIGHT INTO MONDAY NIGHT. THIS WILL PROVIDE
INCREASING WINDS...ESPECIALLY MONDAY. HOWEVER...WINDS PROBABLY
WILL NOT INCREASE QUICKLY ENOUGH TONIGHT TO HELP LOWS MUCH WITH
GUIDANCE GENERALLY ACCEPTABLE. STORMS THAT DEVELOP TO OUR WEST
LATE TONIGHT AIDED BY THETA E ADVECTION IN LOW LEVEL JET AXIS
COULD MOVE ACROSS SECTIONS OF THE AREA MONDAY MORNING...FOR NOW
CONFINED SLGT CHC POPS TO FAR N. OTHERWISE KEPT MONDAY AFTN DRY.
BOOSTED WIND SPEEDS MONDAY TO JUST BELOW WIND ADVISORY CRITERIA
NWRN ZONES. MAX TEMPERATURES PROBABLY A CATEGORY OR SO WARMER
MOST AREAS LOOKS FINE.
INCREASING POPS MONDAY NIGHT INTO TUESDAY STILL ON TRACK AS UPPER
LOW SHIFTS SE A BIT AND LOW LEVEL JET/CONVERGENCE SHIFTS INTO THE
FORECAST AREA MONDAY NIGHT FOLLOWED BY A COLD FRONT TUESDAY.
ALTHOUGH SOME ADJUSTMENTS WERE MADE AND MORE WILL PROBABLY BE
ADDRESSED IN LATER FORECASTS...IT APPEARS HIGHER POPS WILL BE
SHIFTING TOWARD ERN ZONES THRU LATE TUESDAY. IF CLOUDS/SHOWERS
REMAIN WIDESPREAD TUE MAX TEMPS MAY NEED LOWERING.
CONFIDENCE IS LOW IN HOW SCENARIO TUE NIGHT/WED PLAYS OUT AS A
WAVE ROTATING AROUND UPPER LOW COULD HELP GENERATE MCS TO OUR WSW
IN UPSLOPE REGION ACROSS WRN HIGH PLAINS BY WED AM. SOME OF THIS
ACTIVITY COULD SKIRT AREA WED...SPCLY SOUTH...AND LOW CHC POPS
WERE CARRIED GENERALLY ALONG/S OF HIGHWAY 30. HOWEVER...WE COULD
ALSO SEE JUST MAINLY CLOUDS FROM THIS...BUT EITHER PRECIP OR
CLOUDS COULD IMPACT HIGHS. FOR NOW THEY WERE KEPT IN THE 70S TUE
AND WED.
THURSDAY LOOKED DRY WITH INCREASING TSTM CHANCES AGAIN FROM W TO E
FRIDAY INTO SATURDAY AS NEXT TROUGH APPROACHES. NO CHANGES MADE
FROM MODEL/PREVIOUS FORECAST BLEND.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
ZAPOTOCNY
AREA FORECAST DISCUSSION
NWS BUFFALO NY
335 PM EDT SUN JUN 2 2013
.SYNOPSIS...
A COLD FRONT WILL DROP ACROSS THE REGION...USHERING IN COOLER AIR
TONIGHT. THEN CANADIAN HIGH PRESSURE WILL BUILD TOWARD THE REGION
WITH COOL AND DRY WEATHER THROUGH MID-WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
FOR THE REMAINDER OF THE AFTERNOON...EXPECT MAINLY SCATTERED SHOWER
AND THUNDERSTORM ACTIVITY...WITH RADAR SHOWING MOST OF THIS ACROSS
INTERIOR SECTIONS. FOLLOWING THE HRRR AND OTHER HIGH RESOLUTION
GUIDANCE...THESE WILL PROBABLY CONTINUE TO TRACK TO THE EAST BEFORE
FALLING APART TOWARD SUNSET. MEANWHILE...THE BRISK SW FLOW IS
SHADOWING THE NIAGARA FRONTIER FROM BUFFALO TO ROCHESTER...EXTENDING
NE ACROSS LAKE ONTARIO AND TO WATERTOWN. IN THESE AREAS...EXPECT
WIND GUSTS TO 40 MPH FOR DURING THE AFTERNOON HOURS.
MEANWHILE...THE COLD FRONTAL BOUNDARY IS STILL JUST TO THE NORTH OF
LAKE ONTARIO...WITH SHOWERS AND A FEW THUNDERSTORMS ALONG THIS
BOUNDARY. THE FRONT WILL DROP TO THE SOUTH...REACHING THE SOUTH
SHORES OF LAKE ONTARIO JUST SHY OF SUNSET. EXPECT SHOWERS TO WEAKEN
WITH LAKE SHADOWING AND THE LOSS OF DAYTIME HEATING...BUT THERE
STILL IS A CHANCE OF A SHOWER ACROSS THE NIAGARA FRONTIER EARLY THIS
EVENING.
THE FRONT WILL CONTINUE TO DROP SOUTHWARD OVERNIGHT...BUT PROBABLY
WILL BE DRY WITH ITS MAIN INFLUENCE BEING A WIND SHIFT TO THE NW
AND NOTABLY COOLER TEMPERATURES. THE RESULT WILL BE A NOTICEABLE
COOLER NIGHT...WITH TEMPERATURES DOWN INTO THE 40S BY DAYBREAK.
EXPECT A GRADUAL CLEARING TREND TONIGHT...WITH CLOUDS LINGERING
LONGEST ACROSS THE SOUTHERN TIER AND EAST OF LAKE ONTARIO.
HIGH PRESSURE WILL RIDGE EASTWARD INTO THE REGION ON MONDAY...AS AN
UPPER LEVEL LOW IS FORECAST TO REMAIN WELL TO THE NORTH. AFTER SOME
LINGERING MORNING CLOUDS...EXPECT CLOUDS TO SCATTER OUT AND GIVE WAY
TO QUITE A BIT OF AFTERNOON SUNSHINE. DESPITE THE SUN...THE AIR MASS
WILL BE QUITE COLD...WITH HIGHS ONLY IN THE 60S.
&&
.SHORT TERM /MONDAY NIGHT THROUGH THURSDAY NIGHT/...
DRY AND COOLER WEATHER WILL START THIS PERIOD AS HIGH PRESSURE
CENTERED OVER WESTERN HUDSON BAY RIDGES SOUTH ACROSS THE GREAT
LAKES AND INTO NEW YORK STATE. CLEAR SKIES AND MUCH LOWER
DEWPOINTS WILL ALLOW OVERNIGHT TEMPERATURES TO FALL TO THE LOWER
TO MIDDLE 40S... EVEN SOME UPPER 30S POSSIBLE IN THE SOUTHERN TIER
VALLEYS AND BLACK RIVER VALLEY.
THE AIRMASS WILL MODIFY A BIT ON TUESDAY WITH A LITTLE MORE MOISTURE
AND SLIGHTLY WARMER TEMPS. FORECAST SOUNDINGS FOR TUESDAY SHOW A
STRONG SUBSIDENCE INVERSION WHICH SHOULD SUPPRESS MOST IF NOT ALL
CLOUDINESS...ALTHOUGH MID AND HIGH CLOUDS STREAMING IN FROM THE WEST
MAY CLUTTER THE SKY LATE IN THE DAY. HIGH TEMPS ON TUESDAY WILL BE
IN THE LOWER TO MID 60S ACROSS HIGHER ELEVATIONS AND MID 60S TO
AROUND 70 FOR THE LAKE PLAINS. WEDNESDAY WILL BE SIMILAR TO
TUESDAY...A BIT MORE MID CLOUD COVER AND WARMER TEMPS IN THE MID TO
UPPER 60S ACROSS THE EASTERN LAKE ONTARIO REGION AND THE LOWER TO
MID 70S ELSEWHERE.
AN INVERTED SURFACE TROUGH SETS UP ACROSS THE REGION LATE WEDNESDAY
NIGHT THROUGH...ESSENTIALLY A SLOW MOVING WARM FRONT...AND BRINGS AN
INFLUX OF WARM AND MOIST AIR WITH AN INCREASING CHANCE OF SHOWERS
AND THUNDERSTORMS. THE ROUGH TRANSLATES SLOWLY TO EAST THROUGH THIS
PERIOD AND SHOWS SIGNS OF STRENGTHENING AS A LOW LEVEL 40KT JETS
SETS UP LATE THURSDAY NIGHT...INDICATING THE RISK OF STRONGER
THUNDERSTORMS AND HEAVIER RAINS ACROSS CENTRAL AND NORTHERN NY.
TEMPS ON THURSDAY WILL BE IN THE MIDDLE 60S TO THE LOWER 70S...
LIMITED BY THE CLOUD COVER AND PRECIP. LOWS THURSDAY NIGHT WILL BE
MILDER WITH THE WARM ADVECTION ON MORE SOUTHERLY WINDS...READINGS IN
THE LOWER TO MID 50S.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AN UPPER TROUGH WILL CROSS THE REGION DURING THIS PERIOD WITH A
BROAD REGION OF LOWER SURFACE PRESSURE AND WARMER/HUMID AIR IN
PLACE. WILL KEEP CHANCE POPS ACROSS THE AREA FOR FRIDAY AND FRIDAY
NIGHT...THEN TRENDING TO LOWER CHANCE OR SLIGHT CHANCE POPS AS A
DRIER NORTHEASTERLY FLOW DEVELOPS FOR SATURDAY AND SUNDAY.
TEMPERATURES DURING THIS PERIOD WILL CLOSE TO...OR JUST A BIT ABOVE NORMAL
WITH HIGHS GENERALLY IN THE MID 70S AND LOWS IN THE MID TO UPPER 50S.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
THE BACK EDGE OF THE STEADIER RAIN HAS MOVED WELL EAST OF THE
REGION. BEHIND THIS THERE WILL BE SOME SCATTERED DIURNALLY DRIVEN
SHOWERS AND THUNDERSTORMS THIS AFTERNOON...BUT THESE ARE UNLIKELY TO
IMPACT TAF LOCATIONS...WITH MOST OF THIS ACTIVITY FORECAST TO BE
ACROSS INTERIOR SECTIONS. OTHERWISE...THE MAIN IMPACT DURING THIS
TIME WILL BE GUSTY SW WINDS GUSTING 30 TO 35 KTS.
A COLD FRONT WILL DROP SOUTHWARD ACROSS THE REGION ROUGHLY AROUND
00Z. THIS MAY SPARK A SHOWER...AND WILL KEY A WIND SHIFT TO THE
W-NW. A BRIEF PERIOD OF MVFR CIGS ARE POSSIBLE BEHIND THE
FRONT...WITH CIGS LIKELY TO LIFT AND SCATTER DURING THE DAY ON
MONDAY. LEFT OVER MOISTURE MAY RESULT IN BRIEF BKN MVFR CIGS...BUT
THESE WOULD BE VERY SHORT LIVED AS DRIER AIR MIXES IN.
OUTLOOK...
MONDAY NIGHT THROUGH WEDNESDAY...VFR.
THURSDAY AND FRIDAY...MVFR/VFR. A CHANCE OF SHOWERS AND
THUNDERSTORMS.
&&
.MARINE...
AN AREA OF LOW PRESSURE WILL TRACK NORTH OF LAKE ONTARIO TODAY AND
DRAG A COLD FRONT EAST ACROSS THE LAKE THROUGH EARLY EVENING. WHILE
WINDS WILL BE STRONGEST ON LAND...WINDS WILL STILL REMAIN IN SMALL
CRAFT CRITERIA ON MOST OF THE NEARSHORES AND RIVERS UNTIL ABOUT
SUNSET. AFTER THIS...WINDS WILL DIMINISH AS HIGH PRESSURE BUILDS IN
THROUGH MID-WEEK.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR LEZ020-
040-041.
SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
LOZ042>044.
SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
SLZ022-024.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL
SHORT TERM...WCH
LONG TERM...WCH
AVIATION...APFFEL
MARINE...APFFEL/WCH
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
150 PM EDT SUN JUN 2 2013
.SYNOPSIS...
A COLD FRONT WILL PRODUCE NUMEROUS SHOWERS AND THUNDERSTORMS TODAY
ACROSS THE NORTH COUNTRY. THE STRONGER STORMS WILL BE CAPABLE OF
PRODUCE STRONG AND DAMAGING WINDS...SMALL HAIL...AND LOCALIZED
HEAVY DOWNPOURS. CLEARING AND COOLER TEMPERATURES WILL ARRIVE BY
THE START OF THE WORK WEEK.
&&
.NEAR TERM /UNTIL 11 PM THIS EVENING/...
AS OF 117 PM EDT SUNDAY...QUICK UPDATE TO FCST FOR CRNT OBS AND
ADJUSTED TEMPS UP SEVERAL DEGREES. CRNT RADAR SHOWS SHOWERS/STORMS
DEVELOPING ACRS ESSEX COUNTY NY AND THE NORTHERN HUDSON VALLEY
REGION...WITH CRNT MOTION TO THE NE AT 25 TO 35 MPH. LATEST LAPS
DATA CONTS TO SHOW SFC BASED CAPE VALUES BTWN 1500 AND 2500
J/KG...ACRS CPV AND POINTS EAST. IN ADDITION...BEST DYNAMICS AND
LLVL WIND FIELDS ARE APPROACHING OUR WESTERN CWA ATTM. EXPECT
AREAL COVERAGE/INTENSITY OF SHOWERS/STORMS TO INCREASE ACRS MOST
OF CENTRAL/SOUTHERN VT THIS AFTN. MAIN THREAT WL BE
STRONG/DAMAGING WINDS THRU EARLY THIS EVENING. GIVEN CRNT
TRENDS...GREATEST THREAT FOR HEAVY RAIN AND POTENTIAL ISOLATED
FLASH FLOODING WL BE ACRS THE ESSEX COUNTY NY INTO PARTS OF
CENTRAL/SOUTHERN VT. WE WL BE WATCHING THIS POTENTIAL CLOSELY AS
WE PROGRESS THRU THE AFTN/EVENING HOURS. REST OF FCST IN GOOD
SHAPE.
UPDATED ZNS TO REFLECT SVR THUNDERSTORM WATCH #271 FOR EASTERN
DACKS THRU VT UNTIL 8 PM THIS EVENING. REST OF FCST IN GREAT
SHAPE.
UPDATED FCST TO MENTION SHOWERS/STORMS THRU
THIS MORNING FOR CENTRAL/NORTHERN VT AND REMOVED MENTION OF
ENHANCED WORDING THRU THE MORNING HOURS. ALSO...ADJUSTED
TEMPS/DWPTS BASED ON CRNT OBS.
FCST CHALLENGE IS TIMING OF CONVECTION TODAY...FOLLOWED BY AREAL
COVERAGE/INTENSITY OF STORMS THIS AFTN. WATER VAPOR SHOWS POTENT
S/W ENERGY ACRS THE EASTERN GREAT LAKES...WITH ENHANCED RIBBON OF
DEEP LAYER MOISTURE AHEAD OF THIS ENERGY ACRS WESTERN NY/PA. IN
ADDITION...STRONG HGHT FALLS ARE OCCURRING AS MID/UPPER LVL TROF
LIFTS TWD HUDSON`S BAY THIS AFTN AND ASSOCIATED SFC BOUNDARY SWINGS
ACRS OUR CWA.
AT THE SFC...INITIAL PRE-FRNTAL TROF HAS PRODUCED SHOWERS WITH A
FEW EMBEDDED RUMBLES OF THUNDER ACRS THE EASTERN DACKS INTO
NORTHERN/CENTRAL VT THIS MORNING. EXPECT SOME CLRING BEHIND THIS INITIAL
TROF...WHICH WL AID SFC HEATING. WITH TEMPS WARMING TO NEAR
80F...AND DWPTS IN THE U60S TO L70S...SFC BASED CAPE VALUES WL BE
BTWN 2000-2500 J/KG...ESPECIALLY ALONG AND EAST OF THE CPV. EXPECT
ANOTHER ROUND OF STORMS TO REDEVELOP BY EARLY THIS AFTN ACRS THE
EASTERN DACKS...AND BECOME SEVERE AS THEY ENCOUNTER BETTER
INSTABILITY/SHEAR ACRS THE CPV AND MOST OF VT. SOUNDINGS SHOW A
MAINLY UNIDIRECTIONAL WIND FLW THRU 500MB...SUPPORTING LINES OF
STORMS WITH INDIVIDUAL BOW SEGMENTS POSSIBLE...WITH PRIMARY THREAT
BEING STRONG/DAMAGING WINDS. PRE-STORM CHECKLIST SHOWS VERY HIGH
0C LINE AROUND 13KFT THIS AFTN...WHICH INDICATES WE WOULD NEED A
50 TO 55 DBZ TO 35,000 FEET FOR SEVERE HAIL. THEREFORE PRIMARY
THREAT WL BE WINDS...AND GIVEN RECENT SATURATED SOILS...SHALLOW
ROOTED TREES COULD EASILY BE BLOWN DOWN. STORMS SHOULD CLEAR
EASTERN VT BY 8 PM THIS EVENING...BASED ON CRNT RAP AND BTV 4KM
REFLECTIVITY PROGS.
PREVIOUS DISCUSSION...ACTIVE 24-HR PERIOD EXPECTED FOR TODAY/
TONIGHT AS A CD FRNT WILL BEGIN TO PUSH THRU THE AREA. RW/TRW FROM
THE OVERNGT PERIOD STILL SLOWLY PUSHING NORTH THRU CANADIAN BORDER
ZONES ATTM AND SHOULD CLR INTO QUEBEC BFR MAIN PRECIP ARRIVES WITH
FRNT...WHICH IS ONLY TO OUR WEST OVER WESTERN NY/LK ONTARIO. MANY
SPOTS IN THE CWA WILL SEE INSTABILITY INCR DURING THE DAY AS
PSUNNY/MSUNNY WILL ENSUE BFR CONVECTION BEGINS TO
DEVELOP...ALLOWING FOR INCR IN T/TD THROUGHOUT AREA. THIS COMBINED
WITH STRONG SHEAR/LAPSE RATES...LI/S NEARING -4 AND MDL CAPE FROM
BUFKIT SHOWING 1500-2000 J/KG POTENTIAL...WILL ALLOW FOR
DEVELOPMENT OF STRONG TO SEVERE STORMS FOR TODAY/TNGT. SPC(STORM
PREDICTION CENTER) HAS MAJORITY OF CWA UNDER SL RISK FOR SEVERE
CONDITIONS SO HAVE MAINTAINED SEVERE/ENHANCED WORDING IN FORECAST.
MDL PW/S NEARING 1.25-1.60" IN GENERAL WITH LOCALLY HIR AMTS WILL
CREATE QPF AMTS IN GENERAL NEARLY AN INCH FOR ALL AREAS...W/
LOCALLY HIR TOTALS IN HEAVIER DOWNPOURS. W/ SOME AREAS SEEING
TRAINING OF RW/TRW OVERNGT...HYDRO CONCERNS WILL BE AN ISSUE TO
MONITOR. LATEST MDL TREND IS TO BRING BULK OF PRECIP THRU AREA
AFTER MIDNGT TONIGHT. MID-LEVEL DRY AIR WORKING AROUND LOW TO OUR
WEST MAY AID IN SHUTTING DOWN PRECIP QUICKER. FOR NOW WILL KEEP
PRECIP TRENDING DOWN THRU 12Z MONDAY AS TRAINING POTENTIAL MAY
KEEP PRECIP GOING ALONG FRNT A BIT LONGER. TEMP THRU PERIOD NEAR
GUIDANCE...ESPECIALLY EASTERN ZONES WHERE NOT AFFECTED BY CLD
COVER FROM APPORACHING FRNT.
&&
.SHORT TERM /11 PM THIS EVENING THROUGH TUESDAY/...
AS OF 424 AM EDT SUNDAY...GOING INTO MONDAY MORNING...MDLS PUSH
FRNTL BOUNDARY OFF THE NEW ENGLAND COAST...LEAVING THE CWA WITH A
GRADUAL CLRING TREND THRU THE DAY AS SFC HIGH PRESSURE BUILDS EAST
OUT OF THE GREAT LKS REGION. OVER PAST SEVERAL MDL RUNS...UPPER
TROUGH ASSOCIATED W/ THIS SFC FRNT CONTINUES TO SLOWLY PUSH EAST
THRU SOUTHERN PORTIONS OF QUEBEC INTO THE CANADIAN MARITIMES BY
TUESDAY. AS A RESULT WILL CONTINUE TO MENTION SL CHANCE FOR -RW
FOR NE VT THRU EARLY TUESDAY MORNING BFR CLRING OUT. OVERALL TREND
IS FOR NICE WX AS SFC RIDGE REMAINS IN PLACE. STAYING CLOSE TO MDL
GUIDANCE FOR TEMPS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 450 AM EDT SUNDAY...ECMWF AND GFS MODELS SHOW A RIDGE OF
HIGH PRESSURE WILL BUILD INTO THE REGION TUESDAY NIGHT AND WILL
REMAIN OVER THE REGION THROUGH EARLY THURSDAY...WITH FAIR AND DRY
WEATHER EXPECTED. ECMWF AND GFS MODELS SHOW AN UPPER TROUGH OVER
THE WESTERN GREAT LAKES EARLY THURSDAY. THIS UPPER TROUGH WILL
BRING MOISTURE NORTHEAST FROM THE OHIO VALLEY INTO THE REGION ON
THURSDAY AS A STATIONARY FRONTAL BOUNDARY SETS UP ACROSS THE
REGION. ECMWF AND GFS MODELS IN GOOD AGREEMENT IN BRINGING RAIN
SHOWERS TO THE REGION THURSDAY AND FRIDAY. ECMWF AND GFS MODELS
DIFFER ON THE SATURDAY FORECAST WITH THE ECMWF MODEL SHOWING AN
UPPER RIDGE BUILDING INTO THE REGION ON SATURDAY...AND ALSO
BRINGING A DRIER FORECAST TO THE REGION FOR SATURDAY. GFS MODEL
STILL HAS AN UPPER TROUGH OVER THE REGION ON SATURDAY WITH A
CHANCE OF RAIN SHOWERS. GIVEN MODEL DIFFERENCES...WILL OPT TO STAY
WITH PREVIOUS CONTINUITY AND KEEP A CHANCE OF RAIN SHOWERS OVER
THE REGION ON SATURDAY.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
THROUGH 18Z MONDAY...AREAS OF MVFR/IFR EXPECTED IN SHOWERS AND
THUNDERSTORMS THROUGH 00Z MONDAY. SOME THUNDERSTORMS THIS AFTERNOON
MAY BECOME SEVERE WITH GUSTY WINDS AND HAIL POSSIBLE. SHOWERS AND
THUNDERSTORMS WILL BE MOST WIDESPREAD ACROSS VERMONT...AFFECTING
TAF SITES RUT/MPV/BTV. BEST CHANCE FOR SEEING STRONG WIND GUSTS
WILL BE AT RUT/MPV. ACROSS NORTHERN NEW YORK...ACTIVITY WILL BE
MORE SCATTERED...AND NOT AS STRONG AS STORMS IN VERMONT. THREAT OF
SHOWERS AND STORMS WILL END FROM WEST TO EAST LATER THIS AFTERNOON
AND EVENING AS DRY SLOT MOVES INTO THE REGION. EXPECT MAINLY DRY
CONDITIONS AFTER 22Z ACROSS NORTHERN NEW YORK AND CHAMPLAIN
VALLEY...BUT NOT UNTIL 02Z MONDAY IN EASTERN VERMONT. THERE IS
POTENTIAL FOR SOME MVFR OVERNIGHT IN FOG...MAINLY AT
MPV/SLK/RUT...OTHERWISE VFR CONDITIONS EXPECTED FOR OVERNIGHT
TONIGHT THROUGH 18Z MONDAY WITH BKN VFR CIGS. WINDS SOUTHWEST
10-20 KNOTS THIS AFTERNOON...BECOMING LIGHT SOUTHWESTERLY
TONIGHT...THEN WEST 5-15 KNOTS MONDAY. STRONG WIND IN EXCESS OF 40
KNOTS POSSIBLE IN VICINITY OF THUNDERSTORMS THIS AFTERNOON.
OUTLOOK 18Z MONDAY THROUGH FRIDAY...
18Z MONDAY THROUGH FRIDAY...MAINLY VFR CONDITIONS EXPECTED
INTO THURSDAY. INCREASING CHANCES FOR SHOWERS LATER THURSDAY INTO
FRIDAY WITH PSBL MVFR CONDITIONS.
&&
.HYDROLOGY...
SHOWERS AND THUNDERSTORMS WILL DEVELOP THIS AFTERNOON WITH
POTENTIAL FOR LOCALIZED HEAVY RAINFALL. THE STRONGER STORMS WILL
BE CAPABLE OF PRODUCING 1 TO 2 INCHES OF RAIN IN A SHORT PERIOD OF
TIME...WHICH MAY CAUSE ISOLATED FLASH FLOODING...ESPECIALLY IN THE
TRRN. ALSO...MINOR URBAN AND LOW LYING FLOODING WILL BE
POSSIBLE...WITH THESE THUNDERSTORMS. INDIVIDUAL THUNDERSTORMS WILL
MOVE FROM SOUTHWEST TO NORTHEAST AT 20 TO 30 MPH...WITH THE ENITRE BROKEN
LINE SLOWLY MOVING EAST AT 10 TO 15 MPH.
&&
.MARINE...
A LAKE WIND ADVISORY CONTINUES FOR TODAY...EXPECT SOUTH WINDS TO
INCREASE AT 15 TO 25 KNOTS WITH WAVES 1 TO 3 FEET. IN
ADDITION...LAKE THUNDERSTORM ADVISORY CONTINUES WITH THE
EXPECTATION THUNDERSTORMS WILL DEVELOP OVER THE CHAMPLAIN VALLEY
AND OPEN WATERS BY EARLY THIS AFTERNOON.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...JN
NEAR TERM...TABER
SHORT TERM...JN
LONG TERM...WGH
AVIATION...RJS
HYDROLOGY...
MARINE...
AREA FORECAST DISCUSSION
NWS BUFFALO NY
143 PM EDT SUN JUN 2 2013
.SYNOPSIS...
STEADIER RAIN WILL TAPER OFF THIS AFTERNOON...THEN END TONIGHT AS
NOTICEABLY COOLER AND LESS HUMID AIR SPREADS EAST ACROSS WESTERN
AND CENTRAL NEW YORK. THE COOLER AND DRIER CONDITIONS WILL LAST
THROUGH THE FIRST HALF OF THE NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THROUGH EARLY AFTERNOON...THE STEADIEST SHOWERS AND THUNDERSTORMS
HAVE EXITED TO THE EAST. BEHIND THIS IS SLIGHTLY DRIER AIR...WITH
RADAR SHOWING SCATTERED INSTABILITY SHOWERS AND THUNDERSTORMS
DEVELOPING ACROSS INTERIOR SECTIONS. FOLLOWING THE HRRR AND OTHER
HIGH RESOLUTION GUIDANCE...THESE WILL PROBABLY EXPAND IN AREAL
COVERAGE THROUGH LATE AFTERNOON...THEN DIMINISH TOWARD SUNSET. MEANWHILE...THE
BRISK SW FLOW IS SHADOWING THE NIAGARA FRONTIER FROM BUFFALO TO
ROCHESTER...WITH THIS LIKELY TO SPREAD NE TO WATERTOWN THROUGH
MID-AFTERNOON. IN THESE AREAS...EXPECT WIND GUSTS TO 40 MPH FOR
DURING THE AFTERNOON HOURS.
MEANWHILE...THE COLD FRONTAL BOUNDARY IS STILL TO THE NORTH OF
LAKE ONTARIO...WITH SHOWERS AND A FEW THUNDERSTORMS ALONG THIS
BOUNDARY. THE FRONT WILL DROP TO THE SOUTH...REACHING THE SOUTH
SHORES OF LAKE ONTARIO JUST SHY OF SUNSET. EXPECT SHOWERS TO
WEAKEN WITH LAKE SHADOWING AND THE LOSS OF DAYTIME HEATING...BUT
THERE STILL IS A CHANCE OF A SHOWER ACROSS THE NIAGARA FRONTIER
EARLY THIS EVENING.
THE FRONT WILL CONTINUE TO DROP SOUTHWARD OVERNIGHT...BUT PROBABLY
WILL BE DRY WITH ITS MAIN INFLUENCE BEING A WIND SHIFT TO THE NW
AND NOTABLY COOLER TEMPERATURES. THE RESULT WILL BE A NOTICEABLE
COOLER NIGHT...WITH TEMPERATURES DOWN INTO THE 40S BY DAYBREAK.
EXPECT A GRADUAL CLEARING TREND TONIGHT...WITH CLOUDS LINGERING
LONGEST ACROSS THE SOUTHERN TIER AND EAST OF LAKE ONTARIO.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
BEAUTIFUL WEATHER CAN BE EXPECTED ACROSS WESTERN AND NORTH CENTRAL
NEW YORK DURING THE BULK OF THIS PERIOD...AS WE WILL EXPERIENCE A
STRETCH OF SUNNY COMFORTABLE DAYS WITH LOW HUMIDITY. THIS SHOULD
ENABLE THE REGION AN EXCELLENT OPPORTUNITY TO DRY OUT AFTER SOAKING
RAINS FROM THE WEEKEND.
THE BERMUDA HIGH THAT BROUGHT US A LITTLE SUMMER HEAT AND HUMIDITY
HAS LONG SINCE BROKEN DOWN AND WILL NOW BE REPLACED DURING THE FIRST
HALF OF THIS WEEK BY EXPANSIVE CANADIAN HIGH PRESSURE. THIS WILL
INITIALLY RESULT IN SEASONABLY COOL WEATHER WITH DAYTIME HIGHS IN
THE MID 60S MONDAY AND 65 TO 70 ON TUESDAY...BUT TEMPERATURES WILL
SLOWLY PUSH BACK TO NORMAL LEVELS AS WE GET INTO THE MIDDLE OF THE
WEEK. MEANWHILE...WE CAN ANTICIPATE A COUPLE OF CHILLY NIGHTS WITH
LOWS THROUGH WEDNESDAY MORNING IN THE 40S.
AS WE HEAD INTO WEDNESDAY NIGHT THOUGH...A SHORTWAVE DROPPING ACROSS
THE UPPER MID WEST WILL ESTABLISH AN INVERTED TROUGH OVER OUR
WESTERN COUNTIES. THE CONVERGENCE ASSOCIATED WITH THIS LOW LEVEL
FEATURE COULD THEN PRODUCE SOME SHOWERS FROM THE FINGER LAKES
WESTWARD AS THE NIGHT PROGRESSES.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
CONDITIONS WILL GENERALLY BE UNSETTLED DURING THIS PERIOD...
ESPECIALLY THURSDAY AND FRIDAY WHEN AN INVERTED TROUGH WILL SLOWLY
CROSS OUR REGION. THIS WILL RESULT IN SCATTERED SHOWERS AND POSSIBLY
A THUNDERSTORM OR TWO...BUT THE DYNAMICS AND INSTABILITY SHOULD BE
LACKING FOR ANY SIGNIFICANT CONVECTION.
AS WE START NEXT WEEKEND...THE ECMWF IS SUGGESTING THAT MID LEVEL
RIDGING WILL BUILD BACK ACROSS THE LOWER GREAT LAKES AND
RE-ESTABLISH DRY WEATHER FOR AT LETS A PORTION OF OUR FORECAST
AREA.
TEMPERATURES DURING THIS PERIOD WILL CLOSE TO...OR JUST A BIT ABOVE
NORMAL WITH HIGHS GENERALLY IN THE MID 70S AND LOWS IN THE MID TO
UPPER 50S.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
THE BACK EDGE OF THE STEADIER RAIN HAS MOVED WELL EAST OF THE
REGION. THERE WILL BE SCATTERED DIURNALLY DRIVEN SHOWERS AND
THUNDERSTORMS THIS AFTERNOON...BUT THESE ARE UNLIKELY TO IMPACT
TAF LOCATIONS...WITH MOST OF THIS ACTIVITY FORECAST TO BE ACROSS
INTERIOR SECTIONS. OTHERWISE...THE MAIN IMPACT DURING THIS TIME
WILL BE GUSTY SW WINDS TO ABOUT 30 KTS AT MOST SITES.
A COLD FRONT WILL DROP SOUTHWARD ACROSS THE REGION ROUGHLY AROUND
00Z. THIS MAY SPARK A SHOWER...AND WILL KEY A WIND SHIFT TO THE
W-NW. A BRIEF PERIOD OF MVFR CIGS ARE POSSIBLE BEHIND THE
FRONT...WITH CIGS LIKELY TO LIFT AND SCATTER DURING THE DAY ON
MONDAY. LEFT OVER MOISTURE MAY RESULT IN BRIEF BKN MVFR CIGS...BUT
THESE WOULD BE VERY SHORT LIVED AS DRIER AIR MIXES IN.
OUTLOOK...
MONDAY THROUGH WEDNESDAY...VFR.
THURSDAY...MAINLY VFR. A CHANCE OF THUNDERSTORMS.
&&
.MARINE...
AN AREA OF LOW PRESSURE WILL TRACK NORTH OF LAKE ONTARIO TODAY AND
DRAG A COLD FRONT EAST ACROSS THE LAKE THIS AFTERNOON. MODEST
SOUTHWEST WINDS AHEAD OF THE FRONT WILL RESULT IN SCA CONDITIONS
LATER THIS MORNING THROUGH THE AFTERNOON.
&&
.HYDROLOGY...
SEVERAL OF THE BUFFALO CREEKS WILL RUN HIGH TODAY...DUE TO THE TWO
INCHES OF RAIN THAT FELL OVER THE LAST 24 HOURS. NONE OF THESE
ARE EXPECTED TO REACH FLOOD STAGE...BUT THE CAYUGA CREEK IN
LANCASTER AND THE CAZENOVIA CREEK IN EBENEZER ARE BOTH CRESTING
LATE THIS MORNING NEAR OR JUST ABOVE ACTION STAGE.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR LEZ040-
041.
SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR
LEZ020.
SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
LOZ042>044.
SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
SLZ022-024.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL/TJP
SHORT TERM...WCH
LONG TERM...RSH
AVIATION...APFFEL/RSH
MARINE...APFFEL/RSH/TJP
HYDROLOGY...APFFEL
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
123 PM EDT SUN JUN 2 2013
.SYNOPSIS...
A COLD FRONT WILL PRODUCE NUMEROUS SHOWERS AND THUNDERSTORMS TODAY
ACROSS THE NORTH COUNTRY. THE STRONGER STORMS WILL BE CAPABLE OF
PRODUCE STRONG AND DAMAGING WINDS...SMALL HAIL...AND LOCALIZED
HEAVY DOWNPOURS. CLEARING AND COOLER TEMPERATURES WILL ARRIVE BY
THE START OF THE WORK WEEK.
&&
.NEAR TERM /UNTIL 11 PM THIS EVENING/...
AS OF 117 PM EDT SUNDAY...QUICK UPDATE TO FCST FOR CRNT OBS AND
ADJUSTED TEMPS UP SEVERAL DEGREES. CRNT RADAR SHOWS SHOWERS/STORMS
DEVELOPING ACRS ESSEX COUNTY NY AND THE NORTHERN HUDSON VALLEY
REGION...WITH CRNT MOTION TO THE NE AT 25 TO 35 MPH. LATEST LAPS
DATA CONTS TO SHOW SFC BASED CAPE VALUES BTWN 1500 AND 2500
J/KG...ACRS CPV AND POINTS EAST. IN ADDITION...BEST DYNAMICS AND
LLVL WIND FIELDS ARE APPROACHING OUR WESTERN CWA ATTM. EXPECT
AREAL COVERAGE/INTENSITY OF SHOWERS/STORMS TO INCREASE ACRS MOST
OF CENTRAL/SOUTHERN VT THIS AFTN. MAIN THREAT WL BE
STRONG/DAMAGING WINDS THRU EARLY THIS EVENING. GIVEN CRNT
TRENDS...GREATEST THREAT FOR HEAVY RAIN AND POTENTIAL ISOLATED
FLASH FLOODING WL BE ACRS THE ESSEX COUNTY NY INTO PARTS OF
CENTRAL/SOUTHERN VT. WE WL BE WATCHING THIS POTENTIAL CLOSELY AS
WE PROGRESS THRU THE AFTN/EVENING HOURS. REST OF FCST IN GOOD
SHAPE.
UPDATED ZNS TO REFLECT SVR THUNDERSTORM WATCH #271 FOR EASTERN
DACKS THRU VT UNTIL 8 PM THIS EVENING. REST OF FCST IN GREAT
SHAPE.
UPDATED FCST TO MENTION SHOWERS/STORMS THRU
THIS MORNING FOR CENTRAL/NORTHERN VT AND REMOVED MENTION OF
ENHANCED WORDING THRU THE MORNING HOURS. ALSO...ADJUSTED
TEMPS/DWPTS BASED ON CRNT OBS.
FCST CHALLENGE IS TIMING OF CONVECTION TODAY...FOLLOWED BY AREAL
COVERAGE/INTENSITY OF STORMS THIS AFTN. WATER VAPOR SHOWS POTENT
S/W ENERGY ACRS THE EASTERN GREAT LAKES...WITH ENHANCED RIBBON OF
DEEP LAYER MOISTURE AHEAD OF THIS ENERGY ACRS WESTERN NY/PA. IN
ADDITION...STRONG HGHT FALLS ARE OCCURRING AS MID/UPPER LVL TROF
LIFTS TWD HUDSON`S BAY THIS AFTN AND ASSOCIATED SFC BOUNDARY SWINGS
ACRS OUR CWA.
AT THE SFC...INITIAL PRE-FRNTAL TROF HAS PRODUCED SHOWERS WITH A
FEW EMBEDDED RUMBLES OF THUNDER ACRS THE EASTERN DACKS INTO
NORTHERN/CENTRAL VT THIS MORNING. EXPECT SOME CLRING BEHIND THIS INITIAL
TROF...WHICH WL AID SFC HEATING. WITH TEMPS WARMING TO NEAR
80F...AND DWPTS IN THE U60S TO L70S...SFC BASED CAPE VALUES WL BE
BTWN 2000-2500 J/KG...ESPECIALLY ALONG AND EAST OF THE CPV. EXPECT
ANOTHER ROUND OF STORMS TO REDEVELOP BY EARLY THIS AFTN ACRS THE
EASTERN DACKS...AND BECOME SEVERE AS THEY ENCOUNTER BETTER
INSTABILITY/SHEAR ACRS THE CPV AND MOST OF VT. SOUNDINGS SHOW A
MAINLY UNIDIRECTIONAL WIND FLW THRU 500MB...SUPPORTING LINES OF
STORMS WITH INDIVIDUAL BOW SEGMENTS POSSIBLE...WITH PRIMARY THREAT
BEING STRONG/DAMAGING WINDS. PRE-STORM CHECKLIST SHOWS VERY HIGH
0C LINE AROUND 13KFT THIS AFTN...WHICH INDICATES WE WOULD NEED A
50 TO 55 DBZ TO 35,000 FEET FOR SEVERE HAIL. THEREFORE PRIMARY
THREAT WL BE WINDS...AND GIVEN RECENT SATURATED SOILS...SHALLOW
ROOTED TREES COULD EASILY BE BLOWN DOWN. STORMS SHOULD CLEAR
EASTERN VT BY 8 PM THIS EVENING...BASED ON CRNT RAP AND BTV 4KM
REFLECTIVITY PROGS.
PREVIOUS DISCUSSION...ACTIVE 24-HR PERIOD EXPECTED FOR TODAY/
TONIGHT AS A CD FRNT WILL BEGIN TO PUSH THRU THE AREA. RW/TRW FROM
THE OVERNGT PERIOD STILL SLOWLY PUSHING NORTH THRU CANADIAN BORDER
ZONES ATTM AND SHOULD CLR INTO QUEBEC BFR MAIN PRECIP ARRIVES WITH
FRNT...WHICH IS ONLY TO OUR WEST OVER WESTERN NY/LK ONTARIO. MANY
SPOTS IN THE CWA WILL SEE INSTABILITY INCR DURING THE DAY AS
PSUNNY/MSUNNY WILL ENSUE BFR CONVECTION BEGINS TO
DEVELOP...ALLOWING FOR INCR IN T/TD THROUGHOUT AREA. THIS COMBINED
WITH STRONG SHEAR/LAPSE RATES...LI/S NEARING -4 AND MDL CAPE FROM
BUFKIT SHOWING 1500-2000 J/KG POTENTIAL...WILL ALLOW FOR
DEVELOPMENT OF STRONG TO SEVERE STORMS FOR TODAY/TNGT. SPC(STORM
PREDICTION CENTER) HAS MAJORITY OF CWA UNDER SL RISK FOR SEVERE
CONDITIONS SO HAVE MAINTAINED SEVERE/ENHANCED WORDING IN FORECAST.
MDL PW/S NEARING 1.25-1.60" IN GENERAL WITH LOCALLY HIR AMTS WILL
CREATE QPF AMTS IN GENERAL NEARLY AN INCH FOR ALL AREAS...W/
LOCALLY HIR TOTALS IN HEAVIER DOWNPOURS. W/ SOME AREAS SEEING
TRAINING OF RW/TRW OVERNGT...HYDRO CONCERNS WILL BE AN ISSUE TO
MONITOR. LATEST MDL TREND IS TO BRING BULK OF PRECIP THRU AREA
AFTER MIDNGT TONIGHT. MID-LEVEL DRY AIR WORKING AROUND LOW TO OUR
WEST MAY AID IN SHUTTING DOWN PRECIP QUICKER. FOR NOW WILL KEEP
PRECIP TRENDING DOWN THRU 12Z MONDAY AS TRAINING POTENTIAL MAY
KEEP PRECIP GOING ALONG FRNT A BIT LONGER. TEMP THRU PERIOD NEAR
GUIDANCE...ESPECIALLY EASTERN ZONES WHERE NOT AFFECTED BY CLD
COVER FROM APPORACHING FRNT.
&&
.SHORT TERM /11 PM THIS EVENING THROUGH TUESDAY/...
AS OF 424 AM EDT SUNDAY...GOING INTO MONDAY MORNING...MDLS PUSH
FRNTL BOUNDARY OFF THE NEW ENGLAND COAST...LEAVING THE CWA WITH A
GRADUAL CLRING TREND THRU THE DAY AS SFC HIGH PRESSURE BUILDS EAST
OUT OF THE GREAT LKS REGION. OVER PAST SEVERAL MDL RUNS...UPPER
TROUGH ASSOCIATED W/ THIS SFC FRNT CONTINUES TO SLOWLY PUSH EAST
THRU SOUTHERN PORTIONS OF QUEBEC INTO THE CANADIAN MARITIMES BY
TUESDAY. AS A RESULT WILL CONTINUE TO MENTION SL CHANCE FOR -RW
FOR NE VT THRU EARLY TUESDAY MORNING BFR CLRING OUT. OVERALL TREND
IS FOR NICE WX AS SFC RIDGE REMAINS IN PLACE. STAYING CLOSE TO MDL
GUIDANCE FOR TEMPS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 450 AM EDT SUNDAY...ECMWF AND GFS MODELS SHOW A RIDGE OF
HIGH PRESSURE WILL BUILD INTO THE REGION TUESDAY NIGHT AND WILL
REMAIN OVER THE REGION THROUGH EARLY THURSDAY...WITH FAIR AND DRY
WEATHER EXPECTED. ECMWF AND GFS MODELS SHOW AN UPPER TROUGH OVER
THE WESTERN GREAT LAKES EARLY THURSDAY. THIS UPPER TROUGH WILL
BRING MOISTURE NORTHEAST FROM THE OHIO VALLEY INTO THE REGION ON
THURSDAY AS A STATIONARY FRONTAL BOUNDARY SETS UP ACROSS THE
REGION. ECMWF AND GFS MODELS IN GOOD AGREEMENT IN BRINGING RAIN
SHOWERS TO THE REGION THURSDAY AND FRIDAY. ECMWF AND GFS MODELS
DIFFER ON THE SATURDAY FORECAST WITH THE ECMWF MODEL SHOWING AN
UPPER RIDGE BUILDING INTO THE REGION ON SATURDAY...AND ALSO
BRINGING A DRIER FORECAST TO THE REGION FOR SATURDAY. GFS MODEL
STILL HAS AN UPPER TROUGH OVER THE REGION ON SATURDAY WITH A
CHANCE OF RAIN SHOWERS. GIVEN MODEL DIFFERENCES...WILL OPT TO STAY
WITH PREVIOUS CONTINUITY AND KEEP A CHANCE OF RAIN SHOWERS OVER
THE REGION ON SATURDAY.
&&
.AVIATION /17Z SUNDAY THROUGH FRIDAY/...
THROUGH 12Z MONDAY...AREAS OF MVFR/IFR EXPECTED IN SHOWERS AND
THUNDERSTORMS THROUGH 00Z MONDAY. SOME THUNDERSTORMS TODAY MAY
BECOME SEVERE WITH GUSTY WINDS AND HAIL POSSIBLE. COMPOSITE RADAR
LOOP AS OF 1130Z SUNDAY SHOWING SOME SHOWERS WITH SOME EMBEDDED
THUNDERSTORMS ACROSS THE SAINT LAWRENCE VALLEY IN NORTHERN NEW YORK
AT THIS TIME. EXPECTING STRONG TO POSSIBLE SEVERE THUNDERSTORMS TO
DEVELOP ACROSS THE SAINT LAWRENCE VALLEY IN NORTHERN NEW YORK
AROUND 14Z-18Z TODAY...AND THEN SHIFT EASTWARD. EXPECTING SHOWER
AND THUNDERSTORM ACTIVITY COMING TO AN END IN THE SAINT LAWRENCE
VALLEY IN NORTHERN NEW YORK BY 18Z SUNDAY. EXPECTING WIDESPREAD
STRONG TO SEVERE THUNDERSTORMS TO DEVELOP ACROSS THE REMAINDER OF
THE REGION FROM 16Z-21Z SUNDAY. A MID LEVEL DRY SLOT WILL MOVE
INTO THE REGION LATE THIS AFTERNOON...SO EXPECTING ANY
THUNDERSTORM ACTIVITY TO BE CONFINED TO EASTERN AND SOUTHERN
VERMONT BY 00Z MONDAY. EXPECTING ANY THUNDERSTORM ACTIVITY WILL BE
EAST OF THE REGION BY 03Z MONDAY.
OUTLOOK 12Z MONDAY THROUGH THURSDAY...
12Z MONDAY THROUGH THURSDAY...MAINLY VFR CONDITIONS EXPECTED
THROUGH THURSDAY.
&&
.HYDROLOGY...
SHOWERS AND THUNDERSTORMS WILL DEVELOP THIS AFTERNOON WITH
POTENTIAL FOR LOCALIZED HEAVY RAINFALL. THE STRONGER STORMS WILL
BE CAPABLE OF PRODUCING 1 TO 2 INCHES OF RAIN IN A SHORT PERIOD OF
TIME...WHICH MAY CAUSE ISOLATED FLASH FLOODING...ESPECIALLY IN THE
TRRN. ALSO...MINOR URBAN AND LOW LYING FLOODING WILL BE
POSSIBLE...WITH THESE THUNDERSTORMS. INDIVIDUAL THUNDERSTORMS WILL
MOVE FROM SOUTHWEST TO NORTHEAST AT 20 TO 30 MPH...WITH THE ENITRE BROKEN
LINE SLOWLY MOVING EAST AT 10 TO 15 MPH.
&&
.MARINE...
A LAKE WIND ADVISORY CONTINUES FOR TODAY...EXPECT SOUTH WINDS TO
INCREASE AT 15 TO 25 KNOTS WITH WAVES 1 TO 3 FEET. IN
ADDITION...LAKE THUNDERSTORM ADVISORY CONTINUES WITH THE
EXPECTATION THUNDERSTORMS WILL DEVELOP OVER THE CHAMPLAIN VALLEY
AND OPEN WATERS BY EARLY THIS AFTERNOON.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...JN
NEAR TERM...TABER
SHORT TERM...JN
LONG TERM...WGH
AVIATION...WGH/RJS
HYDROLOGY...
MARINE...
AREA FORECAST DISCUSSION...UPDATED AVIATION DISCUSSION
NWS PENDLETON OR
1020 AM PDT SUN JUN 2 2013
.UPDATE...MINOR UPDATES WERE MADE TO THE CURRENT FORECAST. A LARGE
UPPER LEVEL TROUGH OVER WA/ID/MT WILL PUSH AN EMBEDDED WAVE OVER SE
WASHINGTON AND NE OREGON THIS AFTERNOON. THERE IS LIMITED MOISTURE
WITH THE APPROACHING DISTURBANCE...BUT A 100 KNOT JET ALONG THE
BOTTOM OF THE TROUGH WILL RESULT IN SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS FROM THE TRI-CITIES, PENDLETON, AND UKIAH EAST TO THE
IDAHO BORDER. BASED UPON THE HRRR COMPOSITE REFLECTIVITY SHOWING
CONVECTIVE CELLS ACROSS THE WASHINGTON COLUMBIA BASIN...THE FORECAST
WAS UPDATED TO EXTEND ISOLATED THUNDERSTORMS FARTHER WEST TO INCLUDE
THE EASTERN PORTION OF THE LOWER COLUMBIA BASIN. THERE MAY BE A FEW
STRONG THUNDERSTORMS TODAY WITH DIME TO PENNY-SIZE HAIL...BUT SEVERE
STORMS ARE NOT EXPECTED. A FAIRLY TIGHT SURFACE PRESSURE GRADIENT
AND A WEAK MARINE PUSH WILL RESULT IN 20-30 MPH WINDS THROUGH THE
EASTERN SIDE OF THE COLUMBIA RIVER GORGE AND THE KITTITAS VALLEY.
THE SYSTEM WILL HAVE VERY LITTLE IMPACT IN OUR SOUTHERN
ZONES...THEREFORE IT WILL BE MOSTLY SUNNY AND A LITTLE BREEZY ACROSS
CENTRAL OREGON TODAY. THE SYSTEM WILL EXIT THE REGION THIS EVENING
WITH MOST SHOWERS ENDING BY MIDNIGHT. WISTER
AVIATION...18Z TAFS...VFR CONDITIONS TO PREVAIL OVER THE NEXT 24
HOURS. THERE WILL BE SOME CUMULUS BUILDUPS WITH A SLIGHT CHANCE OF
A THUNDERSTORM EAST OF A LINE FROM KPSC TO KPDT THROUGH 06Z. CLOUDS
WILL BE AT 5-8 THOUSAND FEET. WINDS WILL BE 10-20 KT FROM THE NW
WITH A FEW HIGHER GUSTS. WINDS AND CLOUD COVER WILL DIMINISH AFTER
06Z TONIGHT. ML
&&
.PREV DISCUSSION... /ISSUED 431 AM PDT SUN JUN 2 2013/
LONG TERM...TUESDAY NIGHT THROUGH SATURDAY...HIGH PRESSURE WILL
BUILD OVER THE AREA FOR THE EXTENDED. EXPECT MOSTLY DRY CONDITIONS
AND TEMPERATURES TO INCREASE THROUGH THE WORK WEEK...INTO THE
WEEKEND. EXPECT TEMPERATURES TO BE IN THE MID 80S TO LOWER 90S
ACROSS THE LOWER ELEVATIONS...WITH 70S TO LOWER 80S MOUNTAINS.
MODELS DO INDICATE A FEW WEAK DISTURBANCES THAT MAY PASS IN THE
EXTENDED...BUT ONLY ANTICIPATE OCCASIONAL BREEZY CONDITIONS AND
BRIEF INCREASED CLOUD COVER TO BE ASSOCIATED. WEBER
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 73 48 75 50 / 10 10 0 0
ALW 74 53 77 55 / 20 20 0 0
PSC 79 51 80 53 / 10 10 0 0
YKM 78 47 79 49 / 10 10 0 0
HRI 77 50 79 52 / 10 10 0 0
ELN 74 48 79 50 / 10 10 0 0
RDM 72 37 77 39 / 10 10 0 0
LGD 69 44 72 46 / 20 20 10 10
GCD 67 43 70 45 / 10 10 0 0
DLS 77 52 80 54 / 10 10 0 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
TODAY : GREEN
MONDAY : GREEN
TUESDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
85/93
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1251 PM CDT SUN JUN 2 2013
.DISCUSSION...
18Z AVIATION DISCUSSION BELOW.
&&
.AVIATION...
RAIN SHIELD IS SHRINKING ACROSS THE SOUTHWESTERN FORECAST AREA...
LINGERING -RA OVER KLBX`S VICINITY. VFR WITH LIGHT NORTH/VRB
BREEZES THROUGH THE PERIOD...THE HIGH CLOUD DECK BREAKING UP TO
MAINLY SKY CLEAR BY THIS EVENING. CLEAR AND CALM EARLY MORNING
CONDITIONS...WITH A DAMP GROUND...WILL PROVIDE AN ENVIRONMENT
CONDUCIVE TO THE FORMATION OF SHORT-LIVED SHALLOW RADIATIVE FOG.
31
&&
.PREV DISCUSSION... /ISSUED 1053 AM CDT SUN JUN 2 2013/
UPDATE...
SEE MORNING UPDATE.
DISCUSSION...
RAIN HAS PUSHED TO THE COAST AND WILL CONTINUE TO PUSH AWAY FROM
SE TX. A WEAK COLD FRONT EXTENDED FROM EL DORADO ARKANSAS TO
GALVESTON AND THEN WEST TOWARD COTULLA. DRIER AIR HAS BEGUN TO
FILTER INTO SE TX WITH SFC DEW PTS NOW IN THE MID/UPPER 60S.
CONSIDERABLE CLOUD COVER AND WET GROUND WILL LIKELY LIMIT HEATING
TODAY SO HAVE TRIMMED MAX TEMPS A FEW DEGREES. CLOUDS SHOULD BEGIN
TO ERODE IN THE NEXT HOUR OR SO AND PLENTY OF SUNSHINE IS STILL
EXPECTED BY LATE AFTERNOON. RAP MODEL SHOWS SOME REDVELOPMENT
ALONG THE COAST LATE THIS AFTERNOON AND WILL LEAVE 20 POPS IN TO
ACCOUNT FOR THE POSSIBILITY. NEW ZONES OUT BY 11 AM. 43
PREV DISCUSSION... /ISSUED 655 AM CDT SUN JUN 2 2013/
DISCUSSION...
12Z AVIATION DISCUSSION.
AVIATION...
A LINE OF STRONG TO SEVERE THUNDERSTORMS WILL MOVE THROUGH THE
HOUSTON METRO AREA BETWEEN 12 AND 16Z THIS MORNING...AND OFF THE
COAST BETWEEN 14 AND 18Z. WINDS MAY BRIEFLY GUST FROM THE NORTH AT
25 TO 25 KNOTS WITH VISIBILITIES DROPPING TO 1 MILE IN HEAVY RAIN.
CONDITIONS SHOULD GRADUALLY IMPROVE BEHIND THE LINE WITH ALL
TERMINALS VFR BY THIS AFTERNOON. SKIES SHOULD CLEAR OUT OVERNIGHT
WITH LIGHT NORTHERLY WINDS. 44
PREV DISCUSSION... /ISSUED 445 AM CDT SUN JUN 2 2013/
DISCUSSION...
A LINE OF THUNDERSTORMS IS BEGINNING TO FILL IN FROM SOUTH OF
LUFKIN TO COLLEGE STATION. RAIN GAUGES IN TRINITY COUNTY ARE
PICKING UP AS MUCH AS 2.2 INCHES IN 3 HRS AND AS MUCH AS 2 INCHES
OF THAT HAS FALLEN IN THE LAST HOUR. ALSO SEEING A SIGNS OF A REAR
INFLOW JET DEVELOPING IN THE BACK SIDE OF CONVECTION CLOSING IN ON
BRYAN/COLLEGE STATION. BASED ON IR IMAGERY SEEMS CLOUD TOPS ARE
COOLING MORE SO EXPECT DEEP CONVECTION TO CONTINUE THROUGH THE
MORNING. THE MAIN THREAT WILL BE HEAVY RAINFALL ON THE ORDER OF 2
TO 3 INCHES AN HOUR LIKE ALREADY OBSERVED. STORM MOTIONS ARE
EXPECTED TO BE SLOW AS IN 10 TO 2O MPH BUT COULD SEE CELLS
CONTINUE TO DEVELOP ALONG A FRONT PUSHING INTO THE AREA WHICH
COULD TRAIN ACROSS AREAS THAT HAVE ALREADY RECEIVED RAINFALL. SFC
ANALYSIS AT 09Z SHOWS FRONTAL BOUNDARY SLOWLY PUSHING SOUTH FROM
THE ARLATEX THROUGH C TX INTO THE NW HILL COUNTRY. LOOK FOR
CURRENT CONVECTION TO SLOWLY WORK SOUTH AHEAD OF THE FRONT AND
POSSIBLY OUT RUN IT BY A GOOD BIT. THE 00Z HIRES-WRF-ARW/TXTECH
WRF AND HRRR ALL SHOW CURRENT LINE OF CONVECTION WORKING SOUTH
THROUGH SE TX IN A BROKEN LINE. THE LINE THEN WEAKENS AS IT
APPROACHES THE COAST BETWEEN 15Z-18Z. DECIDED TO KEEP SOME 50/60
POPS THROUGH 12-15Z AND THEN GRADUALLY DECREASE RAIN CHANCES.
LOOKS LIKE THIS PART OF THE FORECAST MAY GO THROUGH ADDITIONAL
MODIFICATIONS DEPENDING ON HOW THE CONVECTION EVOLVES THIS
MORNING. DO THINK THIS CONVECTION SHOULD WORK OVER AND STABILIZE
THE ATMOSPHERE FOR THE AFTERNOON SO 20 POPS FOR THE AFTERNOON
LOOKS GOOD BUT IT COULD BE DRY.
AS IT HAS BEEN DISCUSSED BEFORE...MAIN HAZARD THIS MORNING WILL
BE HEAVY RAINFALL. UPPER LEVEL ANALYSIS SHOWS A TROUGH AXIS
WORKING THROUGH THE AREA AND THERE MAY BE ENOUGH UPPER LEVEL
SUPPORT TO KEEP CONVECTION GOING THIS MORNING. EXPECT UPPER LEVEL
ASCENT TO WEAKEN DURING THE AFTERNOON AND CONVERGENCE ALONG THE
FRONT TO WEAKEN AS WELL. THUS BEST CHANCES FOR HEAVY RAIN STILL
THIS MORNING AND THREAT DIMINISHING IN THE AFTERNOON. PRECIP WATER
VALUES THIS MORNING PEAK INVOF CONVECTION AROUND 1.8-2.0 INCHES
AND DECREASE THIS AFTERNOON TO BELOW 1.5 INCHES.
AS FOR THE REST OF THE FORECAST...MODELS STILL BRING WEAK FRONT
TO THE COAST AND POSSIBLY OFF THE COAST. EXPECT SFC DEWPOINT TEMPS
TO DROP INTO THE LOW 60S WHICH WILL SEEM QUITE A BIT DRIER THAN
THE MID 70S DEWPOINTS OF LATE. THIS ALSO MEANS SEASONABLE MIN
TEMPS IN THE MID 60S FOR MON/TUE. EXPECT DRY CONDITIONS TO PERSIST
AS UPPER LEVEL RIDGING BUILDS OVER S TX THROUGH MID WEEK. RIDGE
DOES SHOW SIGNS OF BREAKING DOWN AGAIN FOR THE END OF THE WEEK
WITH AN UPPER LOW OVER THE N PLAINS/MIDWEST/GREAT LAKES. THIS
INTRODUCES NW FLOW ALOFT OVER TX FOR THE END OF THE WEEK WHICH MAY
ALSO SUPPORT A WEAK FRONT MOVING INTO TX ALONG WITH A SERIES OF
WEAK SHORTWAVES THAT COULD INITIATE A FEW ROUNDS OF CONVECTION
ALONG THE RED RIVER AND N TX. POSSIBLE SOME OF THIS CONVECTION
COULD WORK INTO SE TX. WILL KEEP 20 POPS FOR THE END OF THE WEEK
WITH INCREASED MOISTURE AND FAVORABLE UPPER LEVEL PATTERN.
AS WITH TROPICAL SEASON WILL KEEP AN EYE ON CONVECTION IN THE BAY
OF CAMPECHE AND YUCATAN PENINSULA. BOTH GFS/ECMWF SUPPORT
CONVECTION BECOMING ORGANIZED AGAIN FROM REMNANTS OF BARBARA BY
TUESDAY. BOTH MODELS ALSO BRING THIS NEW SYSTEM INTO FLORIDA
THUR/FRI TIME FRAME. THERE WILL BE A DECENT AMOUNT OF WIND SHEAR
SO TOUGH TO KNOW HOW ORGANIZED THE SYSTEM WILL BECOME. NONETHELESS
ALL INDICATIONS ARE THAT THIS WILL NOT BE A THREAT FOR THE TX
COAST.
39
MARINE...
LIGHT ONSHORE FLOW SHOULD BECOME LIGHT AND VARIABLE BY THIS
AFTERNOON IN ADVANCE OF A WEAK COLD FRONT. LIGHT EAST TO SOUTHEAST
WINDS AND 1 TO 2 FOOT SEAS WILL BE THE PREVAILING CONDITION
THROUGH THE MAJORITY OF NEXT WEEK BECAUSE OF A VERY LIGHT PRESSURE
GRADIENT BEHIND THE FRONT. 44
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 64 92 68 93 71 / 10 0 0 0 0
HOUSTON (IAH) 67 92 69 93 71 / 10 0 0 0 0
GALVESTON (GLS) 75 88 76 88 77 / 10 0 0 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...43
AVIATION/MARINE...31