Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 07/05/12
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
650 PM MST WED JUL 4 2012
.UPDATE...UPDATED AVIATION AND PUBLIC DISCUSSIONS.
&&
.SYNOPSIS...
THE WEATHER DISTURBANCE THAT BROUGHT THE RAIN AND CLOUDINESS TO
SOUTH-CENTRAL ARIZONA TODAY WILL WEAKEN AND MOVE NORTH OF THE AREA
OVERNIGHT. AS A RESULT...EXPECT ONLY A SLIGHT CHANCE FOR A LIGHT
RAIN SHOWER OVER SOUTH-CENTRAL ARIZONA THIS EVENING...WITH MOST
AREAS REMAINING DRY. CLEARING FROM THE SOUTHWEST WILL OCCUR LATER
TONIGHT AS THE DISTURBANCE MOVES INTO NORTHERN ARIZONA. MOISTURE
WILL DECREASE DURING THE LATTER HALF OF THE WEEK...LEADING TO
REDUCED STORM CHANCES AND WARMER TEMPERATURES. THUNDERSTORM CHANCES
MAY BEGIN TO RAMP UP OVER THE WEEKEND AND INTO EARLY NEXT WEEK.
&&
.DISCUSSION...
AS OF 630 PM...UPPER DISTURBANCE WAS NEAR THE INTERNATIONAL BORDER
SOUTH OF TUCSON...AND CONTINUED TO WEAKEN AS IT MOVED SLOWLY TOWARD
THE NORTH. RUC ANALYSIS INDICATES UPPER DIVERGENCE ASSOCIATED WITH
THIS DISTURBANCE IS NOT VERY IMPRESSIVE...AND IS FOCUSED MAINLY TO
THE NORTH AND EAST OF OUR FORECAST AREA. VIS/IR SATELLITE IMAGERY
AND REGIONAL RADAR RETURNS INDICATE CHANCE FOR MEASURABLE
PRECIPITATION HAS SHARPLY DIMINISHED OVER OUR FORECAST AREA (WARMING
CLOUD TOPS AND DECREASING AREAL EXTENT/INTENSITY OF PRECIPITATION
ECHOES). ALTHOUGH ATMOSPHERE REMAINS VERY MOIST...CAPE IS QUITE
LIMITED AND WILL CONTINUE TO DECREASE AS THE EVENING WEARS ON.
UPDATED FORECAST FOR THIS EVENING TO LOWER POP/QPF/SKY
COVER...LEAVING ONLY A SLIGHT CHANCE FOR A BRIEF LIGHT SHOWER OVER
THE LOWER DESERT OF SOUTH-CENTRAL AZ (MOST AREAS WILL NOT EXPERIENCE
ADDITIONAL RAINFALL TONIGHT)...AND A CHANCE FOR SHOWERS OVER THE
HIGHER TERRAIN OF SOUTHERN GILA COUNTY. CANNOT RULE OUT A STRAY
THUNDERSTORM THIS EVENING OVER ZONE 24 EAST OF GLOBE...BUT CHANCE IS
TOO LOW TO INCLUDE IN WX GRID.
.PREVIOUS DISCUSSION...
VERY...VERY...UNUSUAL DAY CONTINUES TO EVOLVE OVER THE CENTRAL
ARIZONA DESERTS EARLY THIS AFTERNOON. COPIOUS MOISTURE ADVECTED INTO
SOUTHERN ARIZONA LAST NIGHT AND THIS MORNING...WITH PWAT VALUES
APPROACHING 2 INCHES OVER THE LOWER CENTRAL DESERTS. SURFACE
DEWPOINTS AT NOON WERE MOSTLY IN THE 70S OVER THE SOUTH CENTRAL AZ
DESERTS...WITH A READING OF 70 AT PHOENIX SKY HARBOR. THE MOISTURE
WAS FEEDING IN AHEAD OF AN INVERTED TROF OVER NWRN MEXICO AND AS OF
2 PM THIS FEATURE WAS FINALLY MOVING INTO FAR SRN ARIZONA. SCATTERED
TO NUMEROUS SHOWERS AND THUNDERSTORMS HAVE ALREADY MOVED NORTH AHEAD
OF THIS FEATURE AND ACROSS THE CENTRAL DESERTS...MANY LOCALES HAVE
PICKED UP OVER ONE HALF INCH OF RAIN...WITH VALUES OVER ONE INCH IN
ISOLATED LOCATIONS SUCH AS WEST OF CASA GRANDE. THE SHOWERS HAVE
REALLY COOLED TEMPS DOWN OVER THE DESERTS...MOST 2 PM READINGS WERE
IN THE 70S. THE SKY HARBOR TEMPERATURE WAS DOWN AS LOW AS 73 DEGREES
AN HOUR AGO. RECORD LOW MAX FOR PHOENIX TODAY IS 90... UNFORTUNATELY
THE MIDNIGHT HIGH WAS 91 SO A RECORD CANNOT BE SET. HOWEVER THE
AFTERNOON HIGH WILL STRUGGLE TO REACH THE LOW TO MID 80S...SO THAT
SAYS A LOT. THE COOLING HAS REALLY LIMITED THE INSTABILITY AND CAPE
POTENTIAL SO STRONG STORMS WILL NOT BE LIKELY FOR THE REST OF THE
AFTERNOON. HOWEVER SCATTERED TO NUMEROUS SHOWERS ARE EXPECTED OVER
SOUTH CENTRAL AZ REST OF THE AFTERNOON...ALONG WITH ISOLATED
EMBEDDED THUNDERSTORMS. LOCALLY HEAVY RAIN IS POSSIBLE AND FLOOD
ADVISORIES OR EVEN FLASH FLOOD WARNINGS MAY BE NEEDED IN PLACES
BEFORE THE DAY IS THROUGH. MOST OF THE WEATHER SHOULD FOCUS ON AREAS
FROM MARICOPA COUNTY EASTWARD. AT 2 PM RADAR INDICATED VERY LITTLE
ACTIVITY FROM YUMA/LA PAZ COUNTIES WESTWARD. RAISED POPS TO NEAR 50
PERCENT THIS EVENING OVER SOUTH CENTRAL AZ...EXPECTING WEATHER TO
PERSIST AS THE WAVE MOVES NORTH AND ACROSS OUR AREA.
BY MIDNIGHT THIS FEATURE SHOULD BE EXITING TO THE NORTH AND WE WILL
SEE CONSIDERABLE CLEARING AND DRYING FROM THE SOUTHWEST...AND POPS
WILL LOWER TO JUST 10 PERCENT IN THE PHOENIX AREA AFTER 11 PM.
FLOW ALOFT RAPIDLY BECOMES LESS SUPPORTIVE FOR ORGANIZED
THUNDERSTORM ACTIVITY THURSDAY AND FRIDAY WITH CONFLUENT JET STREAM
FLOW. BOUNDARY LAYER FLOW ALSO BECOMES MORE WESTERLY WITH A GRADUAL
DECLINE IN OVERALL MOISTURE CONTENT. HAVE FURTHER TRIMMED AWAY AT
POPS THROUGH THE END OF THE WEEK...PRIMARILY FOCUSING THE BETTER
CHANCES ACROSS THE HIGHER TERRAIN NORTH AND EAST OF THE PHOENIX
AREA. CORRESPONDINGLY...HAVE ALSO EDGED TEMPERATURES SLIGHTLY
HIGHER HEADING INTO THE WEEKEND. MODELS HAVE BEEN FAIRLY CONSISTENT
IN SHOWING ANOTHER INVERTED TROUGH/EASTWARD MOVING WAVE PROPAGATING
TOWARDS NORTHWEST MEXICO THROUGH THE END OF THE WEEKEND AND EARLY
NEXT WEEK. HOWEVER...THERE IS STILL SUBSTANTIAL UNCERTAINTY
REGARDING THE AMOUNT OF ATTENDANT MOISTURE AND LIFT THAT WILL
ACCOMPANY THIS WAVE...AND HAVE KEPT SOME SLIGHT CHANCE POPS
(SOMEWHAT HIGHER THAN CLIMATOLOGY) ADVERTISED IN THIS FORECAST.
&&
.AVIATION...
SOUTH CENTRAL ARIZONA INCLUDING KPHX...KIWA AND KSDL...
DRY WX WITH LIGHT WIND AND GRADUALLY DECREASING CLOUDS EXPECTED
OVERNIGHT AS WX DISTURBANCE WEAKENS AND MOVES NORTH OF THE AREA.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
BASICALLY CLEAR AND DRY WX EXPECTED AT KIPL OVERNIGHT. DRY
CONDITIONS WITH DECREASING CLOUDS EXPECTED AT KBLH. LIGHT SOUTH TO
SOUTHEAST WIND AT BOTH SITES.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY...
STRONG RIDGING ALOFT OVER THE SOUTHWEST UNITED STATES IS EXPECTED
TO KEEP THE MAJORITY OF THUNDERSTORM ACTIVITY OFF TO THE EAST OVER
EXTREME EASTERN ARIZONA AND NEW MEXICO ON SATURDAY. THIS RIDGE IS
EXPECTED TO BEGIN TO WEAKEN ON SUNDAY...ALLOWING A MORE MOIST
EASTERLY FLOW TO DEVELOP OVER THE REGION. AS A RESULT...EXPECTING
THUNDERSTORM ACTIVITY TO INCREASE SOMEWHAT OVER SOUTHWEST AND SOUTH
CENTRAL ARIZONA FROM SUNDAY ONWARD INTO EARLY NEXT WEEK. SOUTHEAST
CALIFORNIA IS EXPECTED TO REMAIN UNDER A DRIER SOUTHWESTERLY FLOW
THROUGH THE PERIOD. OVERNIGHT HUMIDITY RECOVERIES WILL BE FAIR TO
GOOD OVER ARIZONA...AND FAIR TO POOR OVER SOUTHEAST CALIFORNIA.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
NATIONAL WEATHER SERVICE PHOENIX IS ON THE INTERNET AT
WEATHER.GOV/PHOENIX
DISCUSSION...DG/CB
AVIATION...DG
FIRE WEATHER...PERCHA
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
1040 PM PDT MON JUL 2 2012
...UPDATED AVIATION DISCUSSION...
.SYNOPSIS...
A WEAK UPPER LEVEL LOW OFF THE SOUTHERN CALIFORNIA COAST WILL KEEP
TEMPERATURES A FEW DEGREES BELOW NORMAL THROUGH THURSDAY AND PRODUCE
AREAS OF NIGHT AND MORNING LOW CLOUDS NEAR THE COAST. AS HIGH
PRESSURE EXPANDS WEST...TEMPERATURES WILL WARM TO NEAR NORMAL FOR
THE COAST AND SLIGHTLY ABOVE NORMAL FOR INLAND AREAS THIS WEEKEND.
&&
.SHORT TERM (TONIGHT-THU)...UPDATE
NO CHANGES TO THE FORECAST THIS EVENING. MINIMAL DAY TO DAY CHANGES
SEEM IN GOOD SHAPE OVERALL. AS MENTIONED IN THE EARLIER
DISCUSSION...THERE SHOULD BE A STRONGER ONSHORE TREND FOR TUESDAY
WHICH SHOULD HELP THE LOW CLOUDS ASSOCIATED WITH THE MARINE LAYER
PUSH FARTHER INLAND. LATEST AMDAR SOUNDING AROUND LAX WAS AROUND
1300 FT SO LOW CLOUDS SHOULD FILL IN ACROSS LA COUNTY COASTAL
VALLEYS AND THE VENTURA COUNTY VALLEYS LATE TONIGHT...ALTHOUGH NOT
AS CONFIDENT WITH VENTURA COUNTY VALLEYS BASED ON THE PAST FEW
NIGHTS WHERE LA COUNTY SEEMED TO HAVE BETTER AREAL COVERAGE.
TODAY`S ONSHORE GRADIENTS WERE NOT AS STRONG AS ADVERTISED...IN FACT
OVER 3 MB WEAKER THAN NAM-WRF WAS INDICATING...THEREFORE AFTERNOON
HIGH TEMPS WERE SIMILAR OR A DEGREE OR TWO WARMER IN MOST AREAS.
NAM-WRF MODELS WERE INDICATING LAX-DAG SFC GRADIENT TO BE AROUND
+9.5MB BY LATE TUESDAY AFTERNOON. EVEN IF THIS IS WEAKER BY A COUPLE
OF MILLIBARS...THERE SHOULD BE INCREASED SW TO W WINDS ACROSS THE
WIND PRONE PORTIONS OF THE ANTELOPE VALLEY INCLUDING LAKE PALMDALE
AND ADJACENT FOOTHILLS WITH WIND GUSTS TO 40 MPH CAN BE EXPECTED.
EXPECT SLIGHT COOLING ACROSS THE REGION...EXCEPT FOR THE ANTELOPE
VALLEY WHERE HIGH TEMPS SHOULD REMAIN IN THE MID 90S.
SYNOPTICALLY IN THE SHORT TERM...A WEAK UPPER LVL TROUGH WILL
CONTINUE TO PERSIST ACROSS THE WEST COAST. A SMALL CIRCULATION
WITHIN THE TROUGH WILL PINCH OFF TO A VERY WEAK CLOSED CIRCULATION
OFF SO CAL COAST TOMORROW AND STICK AROUND THROUGH WED HAVING VERY
LITTLE AFFECT TO THE AREA EXCEPT FOR A SLIGHT DEEPENING OF THE
MARINE LAYER AND CONTINUED SLIGHT COOLING TREND INTO WED.
EARLIER RAP13 (FORMERLY RUC MODEL) RUNS INDICATED SOME MARGINAL
INSTABILITY OVER THE LOCAL MOUNTAINS THIS AFTERNOON. ALTHOUGH MODELS
AND MORNING SOUNDING FROM VANDENBERG PICKED UP ON SOME LIMITED MID
LEVEL MOISTURE...ONLY A FEW FLAT CU BUILDUPS OCCURRED AROUND
LOCKWOOD VALLEY AREA. THERE COULD BE A FEW FLAT CU ACROSS THE
MOUNTAINS ONCE AGAIN TOMORROW...BUT VERY ISOLATED AT BEST.
...FROM PREVIOUS DISCUSSION...
.LONG TERM (FRI-MON)...12Z MODELS STILL ON BOARD WITH THE WARMING
TREND FOR THE WEEKEND AS THE PERSISTENT HIGH PRESSURE OVER THE
CENTRAL US STARTS TO EXPAND WESTWARD. WE SHOULD BE LOOKING AT HIGHS
REACHING TRIPLE DIGITS FOR THE ANTELOPE VALLEY AND POSSIBLY EVEN THE
WARMER VALLEY AND MOUNTAIN LOCATIONS AS WELL. STILL A PRETTY DECENT
ONSHORE FLOW EXPECTED THROUGH EARLY NEXT WEEK SO COASTS WILL REMAIN
RELATIVELY COOL BUT STILL ABOVE SEASONAL NORMS WITH MINIMAL MARINE
LYR. MONSOON FLOW APPEARS TO REMAIN FOCUSED ON ARIZONA AND POINTS
EAST BUT MODELS SUGGEST ENOUGH SOUTHEASTERLY FLOW INTO CALIFORNIA TO
WARRANT KEEPING A CLOSE EYE ON THE SITUATION TO SEE IF THE MONSOON
FRONT CREEPS FURTHER WEST THAN CURRENTLY INDICATED. GIVEN THE WARMUP
EXPECTED CONVECTIVE TEMPERATURES WILL BE REACHED MORE EASILY,
ALLOWING FOR A BETTER CHANCE OF AT LEAST SOME AFTERNOON BUILDUPS
OVER THE HIGHER TERRAIN.
&&
.AVIATION...03/0540Z...
STRATUS STARTING TO FILL IN ALONG THE CENTRAL COAST AND ACROSS THE
LAX BASIN. STRATUS SHOULD BE ABLE TO REACH KBUR/KVNY OVERNIGHT AND
WORK IT`S WAY UP TO KOXR. CIGS SHOULD GENERALLY REMAIN AT MVFR/IFR
LEVELS. STRATUS BURNOFF TUESDAY SHOULD BE VERY GOOD...ALTHOUGH
CLEARING COULD BE A BIT LIMITED FOR KLAX AND KOXR.
KLAX...MODERATE CONFIDENCE IN 06Z TAF. THERE IS A 40% CHANCE THAT
MVFR CIGS MAY NOT SCATTER OUT AT ALL TUESDAY AFTERNOON.
KBUR...MODERATE CONFIDENCE IN 06Z TAF. IFR CIGS COULD ARRIVE A
COUPLE HOURS SOONER THAN CURRENT 12Z TAF.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
&&
$$
PUBLIC...KAPLAN/MW
AVIATION...RAT
SYNOPSIS...SUKUP
WWW.WEATHER.GOV/LOSANGELES
AREA FORECAST DISCUSSION
NWS MIAMI FL
131 PM EDT TUE JUL 3 2012
.AVIATION...EAST COAST SEA BREEZE PUSHING WELL INLAND AND
CONVECTION DEVELOPING ALONG THE BOUNDARY WILL BE WELL WEST OF THE
TERMINALS WITH THE EXCEPTION OF KPBI FOR ABOUT AN HOUR WHERE THE
SEA BREEZE IS SLOWER TO PUSH WEST. TENDENCY FOR THE TSRA WILL BE
TO DRIFT WEST AND SO HAVE INCLUDED VCTS FOR THE KAPF TERMINAL LATE
THIS AFTERNOON. OTHERWISE, VFR CONDITIONS WILL PREVAIL THROUGH THE
PERIOD.
KOB
&&
.PREV DISCUSSION... /ISSUED 1103 AM EDT TUE JUL 3 2012/
UPDATE...
THE LATEST SURFACE ANALYSIS SHOWED THE SUBTROPICAL RIDGE AXIS
EXTENDING WEST OVER THE LOCAL AREA WITH LIGHT LOW-LEVEL SW FLOW
NORTH OF THE AXIS OVER THE LAKE REGION AND LIGHT ESE FLOW ACROSS
THE SOUTHERN HALF OF THE AREA. THE LATEST RUC ANALYSIS HAS
INITIALIZED WELL WITH THIS SYNOPTIC PATTERN AND DOES NOT INDICATE
ANY SIGNIFICANT CHANGES THROUGH THE REMAINDER OF THE DAY. MORNING
SOUNDINGS AROUND THE AREA SHOWED A SUFFICIENT AMOUNT OF BOUNDARY
LAYER MOISTURE AND INSTABILITY WITH MAINLY LIGHT FLOW UP THROUGH
THE MID LEVELS. ALTHOUGH LAPSE RATES ARE NOT AS
IMPRESSIVE...PLENTY OF DAYTIME HEATING COMBINED WITH THE MOISTURE
AND INSTABILITY WILL BE ENOUGH TO INITIATE ANOTHER ROUND OF
AFTERNOON/EVENING CONVECTION...MAINLY FROM AROUND 3 PM THROUGH
EARLY EVENING PERIOD. THE LATEST HRRR/WRF MODEL REFLECTIVITIES
INDICATE MAINLY SCATTERED ACTIVITY DEVELOPING OVER THE INLAND
LOCATIONS AND WEST. ALSO...WITH THE LIGHT SW FLOW NORTH OF THE
AXIS...CONVECTION ASSOCIATED WITH THE EAST COAST BREEZE AND LAKE
BREEZE WILL BECOME POSSIBLE OVER MARTIN AND PALM BEACH COUNTIES
AS WELL. SOME OF THESE STORMS MAY BECOME STRONG THE MAIN THREATS
BEING FREQUENT LIGHTNING...HEAVY RAINFALL AND GUSTY WINDS UP TO 50
MPH. THE CURRENT GRIDDED FORECAST APPEARS TO BE IN GOOD SHAPE WITH
NO MAJOR CHANGES EXPECTED. 85/AG
PREV DISCUSSION... /ISSUED 726 AM EDT TUE JUL 3 2012/
AVIATION...NO SIGNIFICANT CHANGES FROM PREVIOUS DISCUSSION...VFR
CONDITIONS SHOULD BE EXPECTED AT ALL TERMINALS THIS MORNING. A FEW
SHOWERS/TSTMS COULD DEVELOP OVER INLAND AREAS THIS AFTERNOON AND BE
STEERED WESTWARD UNDER A MEAN ESE WIND FLOW. WL KEEP VCTS FOR KAPF
DUE TO THE POSSIBILITY OF A STRAY TSTM GETTING CLOSE TO THE TERMINAL
DURING THE LATE AFTERNOON HOURS. SFC WINDS SHOULD PREVAIL FROM E-SE
INCREASING TO AROUND 10 KTS AFTER 15Z AT ALL TERMINALS...EXCEPT FOR
A WEST COAST SEA BREEZE REACHING KAPF AFTER 16Z.
RGH/KOB
PREV DISCUSSION... /ISSUED 340 AM EDT TUE JUL 3 2012/
A DEEP LAYER RIDGE SPRAWLING ACROSS THE SOUTHERN AND CENTRAL GREAT
PLAINS...WHICH EXTENDS SE OVER THE N GUF OF MEX AND THE FLA PENIN
-SULA...WILL BE THE MAIN SYNOPTIC FEATURE IN CONTROL OF THE LOCAL
WEATHER TODAY INTO EARLY WEDNESDAY. A SERIES OF SHORT WAVES...MOVING
OVER THE TOP OF THE DEEP RIDGE AND MOVING SE OVER THE GREAT LAKES
AND THE NEW ENGLAND REGION...DEEPENS AN UPPER TROUGH SE ALONG THE
E U.S. COAST...THE ADJACENT N ATLC AND OVER THE FLA PENINSULA THURS
-DAY NIGHT AND INTO THE WEEKEND. THIS SHOVES THE UPPER RIDGE TO THE
W AND LEAVES THE FLA PENINSULA IN A COL AREA BETWEEN THE HIGH TO THE
W AND THE ATLC RIDGE WHICH WILL PERSIST THROUGH THE WEEKEND AND INTO
EARLY NEXT WEEK.
FOR THE SHORT TERM...(TODAY THROUGH THURSDAY)...A SLOWLY MOISTENING
ATMOSPHERE WILL OCCUR DUE TO LOW LEVEL EASTERLY FLOW BUT A SLOW IN
-CREASE IN MAINLY AFTERNOON CONVECTION INTERIOR AND W CAN BE EXPECT
-ED DUE TO CONVERGING AFTERNOON SEA BREEZES. BY WEDNESDAY AND THURS
-DAY...THE CHANCES OF CONVECTION INCREASE WITH THE UPPER FLOW BE
-COMING MORE SOUTHERLY WITH AFTERNOON/EVENING CONVECTION BECOMING
CENTERED MORE TOWARD THE INTERIOR AND THE LAKE OKEECHOBEE REGION.
MAX TEMPERATURES WILL REMAIN SLIGHTLY ABOVE NORMS EACH DAY AS HIGHS
REACH THE LOWER TO MID 90S WITH NEAR 90 AT THE IMMEDIATE COASTAL
AREAS DUE TO THE SEA BREEZES. HEAT INDICES IN THE AREAS OF THE IN
-TERIOR WILL RISE ABOVE 105 DEGREES. CIRCULATION ABOUT BROAD LOW
PRESSURE SYSTEM IN THE SOUTHERN CARIBBEAN...PULLS A WEAK TROPICAL
WAVE/MOISTURE TOWARD S FLA WEDNESDAY AND THURSDAY WITH AN INCREASE
IN THE CHANCES OF RAIN.
LONG TERM (FRIDAY-SATURDAY)...FRIDAY MAY SEE A SLIGHT DECREASE IN
THE CHANCES OF RAIN BUT IS EXPECTED TO INCREASE AGAIN OVER THE
WEEKEND AND INTO EARLY NEXT WEEK AS ANOTHER WEAK TROPICAL WAVE
MOVES TOWARD S FLA OVER THE WEEKEND.
MARINE...
EASTERLY WINDS...LESS THAN 15 KNOTS WITH SEAS 2 FEET OR LESS CAN BE
EXPECTED THROUGH THE PERIOD EXPECT IN THE AREAS OF PRECIPITATION.
THERE WILL BE THOUGH A MODERATE RISK OF RIP CURRENTS AT THE ATLANTIC
BEACHES TODAY.
FIRE WEATHER...
NO CONCERNS AS RH VALUES REMAIN ABOVE CRITICAL LEVELS EACH DAY.
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MIAMI FL
1103 AM EDT TUE JUL 3 2012
.UPDATE...
THE LATEST SURFACE ANALYSIS SHOWED THE SUBTROPICAL RIDGE AXIS
EXTENDING WEST OVER THE LOCAL AREA WITH LIGHT LOW-LEVEL SW FLOW
NORTH OF THE AXIS OVER THE LAKE REGION AND LIGHT ESE FLOW ACROSS
THE SOUTHERN HALF OF THE AREA. THE LATEST RUC ANALYSIS HAS
INITIALIZED WELL WITH THIS SYNOPTIC PATTERN AND DOES NOT INDICATE
ANY SIGNIFICANT CHANGES THROUGH THE REMAINDER OF THE DAY. MORNING
SOUNDINGS AROUND THE AREA SHOWED A SUFFICIENT AMOUNT OF BOUNDARY
LAYER MOISTURE AND INSTABILITY WITH MAINLY LIGHT FLOW UP THROUGH
THE MID LEVELS. ALTHOUGH LAPSE RATES ARE NOT AS
IMPRESSIVE...PLENTY OF DAYTIME HEATING COMBINED WITH THE MOISTURE
AND INSTABILITY WILL BE ENOUGH TO INITIATE ANOTHER ROUND OF
AFTERNOON/EVENING CONVECTION...MAINLY FROM AROUND 3 PM THROUGH
EARLY EVENING PERIOD. THE LATEST HRRR/WRF MODEL REFLECTIVITIES
INDICATE MAINLY SCATTERED ACTIVITY DEVELOPING OVER THE INLAND
LOCATIONS AND WEST. ALSO...WITH THE LIGHT SW FLOW NORTH OF THE
AXIS...CONVECTION ASSOCIATED WITH THE EAST COAST BREEZE AND LAKE
BREEZE WILL BECOME POSSIBLE OVER MARTIN AND PALM BEACH COUNTIES
AS WELL. SOME OF THESE STORMS MAY BECOME STRONG THE MAIN THREATS
BEING FREQUENT LIGHTNING...HEAVY RAINFALL AND GUSTY WINDS UP TO 50
MPH. THE CURRENT GRIDDED FORECAST APPEARS TO BE IN GOOD SHAPE WITH
NO MAJOR CHANGES EXPECTED. 85/AG
&&
.PREV DISCUSSION... /ISSUED 726 AM EDT TUE JUL 3 2012/
AVIATION...NO SIGNIFICANT CHANGES FROM PREVIOUS DISCUSSION...VFR
CONDITIONS SHOULD BE EXPECTED AT ALL TERMINALS THIS MORNING. A FEW
SHOWERS/TSTMS COULD DEVELOP OVER INLAND AREAS THIS AFTERNOON AND BE
STEERED WESTWARD UNDER A MEAN ESE WIND FLOW. WL KEEP VCTS FOR KAPF
DUE TO THE POSSIBILITY OF A STRAY TSTM GETTING CLOSE TO THE TERMINAL
DURING THE LATE AFTERNOON HOURS. SFC WINDS SHOULD PREVAIL FROM E-SE
INCREASING TO AROUND 10 KTS AFTER 15Z AT ALL TERMINALS...EXCEPT FOR
A WEST COAST SEA BREEZE REACHING KAPF AFTER 16Z.
RGH/KOB
PREV DISCUSSION... /ISSUED 340 AM EDT TUE JUL 3 2012/
A DEEP LAYER RIDGE SPRAWLING ACROSS THE SOUTHERN AND CENTRAL GREAT
PLAINS...WHICH EXTENDS SE OVER THE N GUF OF MEX AND THE FLA PENIN
-SULA...WILL BE THE MAIN SYNOPTIC FEATURE IN CONTROL OF THE LOCAL
WEATHER TODAY INTO EARLY WEDNESDAY. A SERIES OF SHORT WAVES...MOVING
OVER THE TOP OF THE DEEP RIDGE AND MOVING SE OVER THE GREAT LAKES
AND THE NEW ENGLAND REGION...DEEPENS AN UPPER TROUGH SE ALONG THE
E U.S. COAST...THE ADJACENT N ATLC AND OVER THE FLA PENINSULA THURS
-DAY NIGHT AND INTO THE WEEKEND. THIS SHOVES THE UPPER RIDGE TO THE
W AND LEAVES THE FLA PENINSULA IN A COL AREA BETWEEN THE HIGH TO THE
W AND THE ATLC RIDGE WHICH WILL PERSIST THROUGH THE WEEKEND AND INTO
EARLY NEXT WEEK.
FOR THE SHORT TERM...(TODAY THROUGH THURSDAY)...A SLOWLY MOISTENING
ATMOSPHERE WILL OCCUR DUE TO LOW LEVEL EASTERLY FLOW BUT A SLOW IN
-CREASE IN MAINLY AFTERNOON CONVECTION INTERIOR AND W CAN BE EXPECT
-ED DUE TO CONVERGING AFTERNOON SEA BREEZES. BY WEDNESDAY AND THURS
-DAY...THE CHANCES OF CONVECTION INCREASE WITH THE UPPER FLOW BE
-COMING MORE SOUTHERLY WITH AFTERNOON/EVENING CONVECTION BECOMING
CENTERED MORE TOWARD THE INTERIOR AND THE LAKE OKEECHOBEE REGION.
MAX TEMPERATURES WILL REMAIN SLIGHTLY ABOVE NORMS EACH DAY AS HIGHS
REACH THE LOWER TO MID 90S WITH NEAR 90 AT THE IMMEDIATE COASTAL
AREAS DUE TO THE SEA BREEZES. HEAT INDICES IN THE AREAS OF THE IN
-TERIOR WILL RISE ABOVE 105 DEGREES. CIRCULATION ABOUT BROAD LOW
PRESSURE SYSTEM IN THE SOUTHERN CARIBBEAN...PULLS A WEAK TROPICAL
WAVE/MOISTURE TOWARD S FLA WEDNESDAY AND THURSDAY WITH AN INCREASE
IN THE CHANCES OF RAIN.
LONG TERM (FRIDAY-SATURDAY)...FRIDAY MAY SEE A SLIGHT DECREASE IN
THE CHANCES OF RAIN BUT IS EXPECTED TO INCREASE AGAIN OVER THE
WEEKEND AND INTO EARLY NEXT WEEK AS ANOTHER WEAK TROPICAL WAVE
MOVES TOWARD S FLA OVER THE WEEKEND.
MARINE...
EASTERLY WINDS...LESS THAN 15 KNOTS WITH SEAS 2 FEET OR LESS CAN BE
EXPECTED THROUGH THE PERIOD EXPECT IN THE AREAS OF PRECIPITATION.
THERE WILL BE THOUGH A MODERATE RISK OF RIP CURRENTS AT THE ATLANTIC
BEACHES TODAY.
FIRE WEATHER...
NO CONCERNS AS RH VALUES REMAIN ABOVE CRITICAL LEVELS EACH DAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 90 77 89 78 / 10 10 30 20
FORT LAUDERDALE 90 79 90 79 / 10 10 20 20
MIAMI 91 79 90 79 / 10 10 20 20
NAPLES 92 75 91 76 / 10 10 20 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...85/AG
AVIATION/RADAR...30/KOB
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
505 PM CDT TUE JUL 3 2012
.DISCUSSION...
412 PM CDT
SYNOPSIS...LARGE SCALE PATTERNS CHANGES VERY LITTLE THROUGH
FRIDAY...WITH A LARGE RIDGE STRETCHED ACROSS CONUS. MODEL CONSENSUS
IS HIGH THAT THE UPPER LEVEL RIDGE WILL BE CENTERED OVER
MISSOURI. AN UPPER LEVEL LOW MOVES ACROSS THE SOUTHERN CANADIAN
PRAIRIES AND REACHES HUDSON BAY LATE THURSDAY. THE UPPER LEVEL
TROUGH MOVES OVER QUEBEC OVER THE WEEKEND...WHILE THE RIDGE CENTER
SHIFTS WESTWARD. AS A RESULT...MUCH WELCOMED NORTHWEST FLOW USHERS
IN SLIGHTLY COOLER AIR FOR EARLY NEXT WEEK.
GIVEN UNCERTAINTIES IN CONVECTIVE DEVELOPMENT AND LAKE BREEZE
INFLUENCE...DECIDED TO EXTEND THE HEAT WATCH THROUGH 02Z FRIDAY FOR
COOK COUNTY...AND EXTEND THE CURRENT HEAT ADVISORY FOR THE REMAINDER
OF THE CWA THROUGH 02Z FRIDAY AS WELL.
THROUGH TONIGHT...
DESPITE OVER 3000 J/KG OF CAPE PER THE LATEST RUC ANALYSIS AND NO
CIN...A LACK OF FORCING HAS RESULTED IN PRIMARILY CLEAR SKIES AND A
LACK OF CONVECTIVE DEVELOPMENT. GIVEN LATEST TRENDS AND NO CLEAR
FORCING MECHANISM...DECIDED TO GO WITH A DRY FORECAST THROUGH
TONIGHT. THERE IS A MINIMAL CHANCE THAT A STRAY THUNDERSTORM MAY
DEVELOP...BUT GIVEN THE LACK OF OBVIOUS FORCING...BETTING AGAINST
IT.
WE STAY WARM TONIGHT WITH LOW TEMPS IN THE MID 70S...EXCEPT FOR NEAR
80 DOWNTOWN. HEAT INDICES TONIGHT WILL REMAIN IN THE 70S...PROVIDING
LITTLE RELIEF FROM THE MUGGY CONDITIONS.
TOMORROW AND THURSDAY...
TEMPERATURES CONTINUE TO INCREASE ON BOTH WEDNESDAY AND THURSDAY.
THE LATEST ECMWF RUN INDICATES THURSDAY WILL BE THE WARMEST DAY IN
THE FORECAST PERIOD. RAISED TEMPS ON WEDNESDAY AND THURSDAY BY A
COUPLE OF DEGREES. MIXING STRAIGHT DOWN FROM 850 HPA GAVE TEMPS IN
THE LOW TO MID HUNDREDS ON BOTH DAYS AND DECIDED THAT WAS TOO MUCH
OF AN INCREASE THIS FAR OUT. COULD SEE THURSDAY MAX TEMPS BE EVEN A
DEGREE OR TWO HIGHER. EITHER WAY BOTH DAYS WILL BE NEAR TO SLIGHTLY
ABOVE 100. MAX HEAT INDICES ON BOTH DAYS WILL VARY BETWEEN 100 AND
113 DEGREES. NOT EXPECTING MUCH RELIEF OVERNIGHT AS HEAT INDICES
WILL REMAIN IN THE MID 70S EXCEPT FOR NEAR 80 DOWNTOWN.
MODELS INDICATE CONVECTION WILL FIRE TO OUR NORTH AND TRY TO ROLL
DOWN THE FRONT OF THE RIDGE INTO NORTHEAST IL AND NORTHWEST IN.
GUIDANCE SUGGESTS THE CONVECTION WILL FIZZLE BEFORE CROSSING THE
WI/IL BORDER. HOWEVER...GIVEN A LAKE BREEZE IS LIKELY TO DEVELOP
TOMORROW AFTERNOON...KEPT THE CHANCE OF CONVECTION ALONG THE
LAKESHORE LATE TOMORROW AFTERNOON. A LAKE BREEZE IS ALSO LIKELY
THURSDAY AFTERNOON. BOTH OF THESE LAKE BREEZES COULD PROVIDE LATE
DAY RELIEF FROM THE HEAT...BUT AS OF RIGHT NOW BOTH ARE EXPECTED TO
DEVELOP AFTER DOWNTOWN HITS ITS MAX TEMP.
EXTENDED...FRIDAY THROUGH MONDAY...
THE EXTENDED FEATURES A TRANSITION FROM THE PERSISTENT UPPER LEVEL
RIDGE TO UPPER LEVEL NORTHWEST FLOW. THE OPPRESSIVE HEAT CONTINUES
THROUGH THE EARLY PART OF THE WEEKEND WITH RELIEF ARRIVING IN THE
FORM OF A BACKDOOR COLD FRONT. THE TIMING OF THIS COLD FRONT IS
DEBATABLE WITH THE MODELS DIFFERING ON ITS ARRIVAL. LEANING TOWARD
THE ECMWF/S STEADY SOLUTION WHICH FEATURES THE COLD FRONT MOVING IN
SUNDAY NIGHT INTO MONDAY MORNING. AS SUCH...RAISED ALLBLEND TEMPS
ON SATURDAY. LOOKING AT TEMPS AT OR JUST ABOVE 100 DEGREES ON
FRIDAY...THEN A BIT COOLER WITH MAX TEMPS IN THE UPPER 80S TO MID
90S. IF TRENDS CONTINUE TO LEAN TOWARD THE ECMWF...EXPECTING FUTURE
FORECASTS TO RAISE TEMPS EVEN FURTHER ON BOTH FRIDAY AND
SATURDAY...WITH SATURDAY MOST LIKELY REMAINING COOLER THAN FRIDAY.
ONCE AGAIN...TEMPS AND PRECIP ALL DEPEND ON THE TIMING OF THIS
FRONT. LEANED TOWARD THE ECMWF WITH THE EXTENDED PRECIP
FORECAST...BUT TO BLEND WELL WITH THE NEIGHBORS AND GIVEN HOW FAR
OUT THE FORECAST PERIOD IS...BLENDED IN A LITTLE OF THE GFS. SUNDAY
NIGHT AND MONDAY LOOK LIKE THE BEST CHANCES OF PRECIP AS THE FRONT
SINKS SOUTH THROUGH THE CWA. TEMPS BEHIND THE FROPA LOOK NEAR
NORMAL.
JEE
&&
.CLIMATE...
520 AM CDT
CHICAGO ROCKFORD
HIGH LOW HIGH LOW
TUE 102 78 99 74
1949 1911 1925 1911
WED 102 80 101 77
1911 1921 1911 1977
THU 102 82 100 77
1911 1911 1911 1911
FRI 99 80 102 73
1988 1977 1936 1948
THE ALL TIME RECORD HIGH FOR CHICAGO IS 105 SET BACK ON JULY 24
1934...AND FOR ROCKFORD IS 112 SET ON JULY 14 1936.
IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 22Z...
* SLIGHT THREAT OF ISOLATED TS LATE AFTERNOON-MID EVENING.
TRS/KB
//DISCUSSION...UPDATED 20Z...
A SHORT WAVE MOVING ACROSS CENTRAL TOWARD EAST CENTRAL WI AT MID
AFTERNOON WAS GENERATING SOME PATCHES OF ALTOCUMULUS...INDICATING
AT LEAST MID LEVEL LIFT. NON-IMPRESSIVE CU FIELD ACROSS SOUTHERN
WI WILL NEED TO BE MONITORED FOR ANY SIGNS OF ENHANCEMENT AS THE
SHORT WAVE CONTINUES TO THE ESE. BEST AREA FOR CONVECTIVE
INITIATION LOOKS TO BE IN E CENTRAL AND PORTIONS OF SE WI DURING
LATE AFTERNOON. STEERING FLOW WOULD THEN TAKE ANY CELLS
SOUTHEASTWARD OUT OVER THE LAKE...UNLESS TS FIRE SOONER /FURTHER
W/ THAN CURRENTLY EXPECTED THEN POTENTIALLY COULD MAKE IT TO THE
FAR NE CORNER OF IL.
TRS
PREVIOUS DISCUSSION...UPDATED 18Z...
THE OUTFLOW BOUNDARY THAT WAS GENERATED BY THUNDERSTORMS THAT
OCCURRED OVER PARTS OF SOUTHERN WI DURING THE FIRST PART OF THE
MORNING WEAKENED AS IT MOVED SOUTH INTO NORTHERN IL. BY 17Z IT
HAD HAD PRETTY MUCH WASHED OUT WITH MOST METARS AND MESONET OBS
SHOWING SURFACE WINDS RETURNING TO LIGHT SSW-SW.
CONVECTIVE TEMPERATURE IS ABOUT 93F AND NOT REACHED YET SO
CUMULUS HAS NOT MADE AN APPEARANCE OVER THE AREA YET. MOST OF THE
DEBRIS CLOUDS FROM THE WI THUNDERSTORMS HAS THINNED CONSIDERABLY
SO GOOD SURFACE HEATING DURING THE FIRST PART OF THE AFTERNOON
SHOULD RAISE TEMPERATURES ENOUGH TO POP CUMULUS 20-21Z.
HOWEVER...WITHOUT ANY SURFACE FEATURE IN THE AREA TO FOCUS LOW
LEVEL CONVERGENCE NOR ANY MID OR UPPER LEVEL DISTURBANCES...AS
WELL AS A SLIGHT WARMING OF MID LEVELS...CHANCES OF ANYTHING
MORE THAN AN ISOLATED THUNDERSTORM DURING THE LATER AFTERNOON OR
THIS EVENING LOOKS TO BE VERY LOW.
A SIGNIFICANT SHORT WAVE IS UPSTREAM...CURRENTLY MOVING OVER THE
DAKOTAS...BUT WITH THE UPPER RIDGE TO REBUILD OVER THE LOCAL AREA
BETWEEN THE SOUTHERN END OF A SHORT WAVE TROUGH MOVING FURTHER E
ACROSS THE NORTHERN GREAT LAKES AND THE NORTHERN PLAINS SHORT
WAVE MOVING E FROM THE NORTHERN PLAINS TOWARD SOUTHERN MANITOBA
AND NORTHWEST MN OVERNIGHT AND WED MORNING...DO NOT SEE ANY
PARTICULAR TIME FRAME WHEN CHANCES WOULD BE HIGH ENOUGH FOR
MENTION IN THE TAFORS.
TRS
//ORD AND MDW CONFIDENCE...UPDATED 22Z...
* HIGH CONFIDENCE IN ALL ELEMENTS THIS AFTERNOON AND THIS EVENING.
TRS/KJB
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
* WEDNESDAY NIGHT...VFR. SLIGHT CHANCE OF TSRA.
* THURSDAY...VFR.
* FRIDAY...VFR. SLIGHT CHANCE OF TSRA FRIDAY NIGHT.
* SATURDAY...VFR. SLIGHT CHANCE OF TSRA.
&&
.MARINE...
247 PM CDT
LOW PRESSURE PASSING NORTH OF THE LAKES ACROSS ONTARIO THIS EVENING
WILL TRAIL A WEAK COLD FRONT ACROSS THE WESTERN GREAT LAKES LATER
TONIGHT AND WEDNESDAY. THIS FRONT IS EXPECTED TO WASH OUT AS IT
SLIDES DOWN ACROSS CENTRAL AND SOUTHERN LAKE MICHIGAN WEDNESDAY...
WITH THE FRONT REDEVELOPING BACK TO THE NORTH IN RESPONSE TO ANOTHER
LOW MOVING ACROSS SASKATCHEWAN AND MANITOBA. THIS SECOND LOW WILL
MOVE EAST ACROSS NORTHERN ONTARIO AND HUDSON BAY THROUGH THURSDAY
AND WILL DRAG ANOTHER FAIRLY WEAK COLD FRONT ACROSS LAKE MICHIGAN
THURSDAY NIGHT INTO FRIDAY. WHILE THE INITIAL PUSH OF COOLER WILL BE
RATHER MEAGER...HIGH PRESSURE BUILDING ACROSS ONTARIO AND THE
NORTHERN LAKES SATURDAY WILL BRING SLIGHTLY STRONGER NORTH WINDS AND
COOLER AIR ACROSS LAKE MICHIGAN INTO THE WEEKEND.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...HEAT ADVISORY...ILZ014 UNTIL 7 AM WEDNESDAY.
EXCESSIVE HEAT WATCH...ILZ014...7 AM WEDNESDAY TO 9 PM THURSDAY.
HEAT ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-ILZ011-
ILZ012-ILZ013-ILZ019-ILZ020-ILZ021-ILZ022-ILZ023-ILZ032-
ILZ033-ILZ039 UNTIL 9 PM THURSDAY.
IN...HEAT ADVISORY...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 9 PM
THURSDAY.
LM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
415 PM CDT TUE JUL 3 2012
.DISCUSSION...
412 PM CDT
SYNOPSIS...LARGE SCALE PATTERNS CHANGES VERY LITTLE THROUGH
FRIDAY...WITH A LARGE RIDGE STRETCHED ACROSS CONUS. MODEL CONSENSUS
IS HIGH THAT THE UPPER LEVEL RIDGE WILL BE CENTERED OVER
MISSOURI. AN UPPER LEVEL LOW MOVES ACROSS THE SOUTHERN CANADIAN
PRAIRIES AND REACHES HUDSON BAY LATE THURSDAY. THE UPPER LEVEL
TROUGH MOVES OVER QUEBEC OVER THE WEEKEND...WHILE THE RIDGE CENTER
SHIFTS WESTWARD. AS A RESULT...MUCH WELCOMED NORTHWEST FLOW USHERS
IN SLIGHTLY COOLER AIR FOR EARLY NEXT WEEK.
GIVEN UNCERTAINTIES IN CONVECTIVE DEVELOPMENT AND LAKE BREEZE
INFLUENCE...DECIDED TO EXTEND THE HEAT WATCH THROUGH 02Z FRIDAY FOR
COOK COUNTY...AND EXTEND THE CURRENT HEAT ADVISORY FOR THE REMAINDER
OF THE CWA THROUGH 02Z FRIDAY AS WELL.
THROUGH TONIGHT...
DESPITE OVER 3000 J/KG OF CAPE PER THE LATEST RUC ANALYSIS AND NO
CIN...A LACK OF FORCING HAS RESULTED IN PRIMARILY CLEAR SKIES AND A
LACK OF CONVECTIVE DEVELOPMENT. GIVEN LATEST TRENDS AND NO CLEAR
FORCING MECHANISM...DECIDED TO GO WITH A DRY FORECAST THROUGH
TONIGHT. THERE IS A MINIMAL CHANCE THAT A STRAY THUNDERSTORM MAY
DEVELOP...BUT GIVEN THE LACK OF OBVIOUS FORCING...BETTING AGAINST
IT.
WE STAY WARM TONIGHT WITH LOW TEMPS IN THE MID 70S...EXCEPT FOR NEAR
80 DOWNTOWN. HEAT INDICES TONIGHT WILL REMAIN IN THE 70S...PROVIDING
LITTLE RELIEF FROM THE MUGGY CONDITIONS.
TOMORROW AND THURSDAY...
TEMPERATURES CONTINUE TO INCREASE ON BOTH WEDNESDAY AND THURSDAY.
THE LATEST ECMWF RUN INDICATES THURSDAY WILL BE THE WARMEST DAY IN
THE FORECAST PERIOD. RAISED TEMPS ON WEDNESDAY AND THURSDAY BY A
COUPLE OF DEGREES. MIXING STRAIGHT DOWN FROM 850 HPA GAVE TEMPS IN
THE LOW TO MID HUNDREDS ON BOTH DAYS AND DECIDED THAT WAS TOO MUCH
OF AN INCREASE THIS FAR OUT. COULD SEE THURSDAY MAX TEMPS BE EVEN A
DEGREE OR TWO HIGHER. EITHER WAY BOTH DAYS WILL BE NEAR TO SLIGHTLY
ABOVE 100. MAX HEAT INDICES ON BOTH DAYS WILL VARY BETWEEN 100 AND
113 DEGREES. NOT EXPECTING MUCH RELIEF OVERNIGHT AS HEAT INDICES
WILL REMAIN IN THE MID 70S EXCEPT FOR NEAR 80 DOWNTOWN.
MODELS INDICATE CONVECTION WILL FIRE TO OUR NORTH AND TRY TO ROLL
DOWN THE FRONT OF THE RIDGE INTO NORTHEAST IL AND NORTHWEST IN.
GUIDANCE SUGGESTS THE CONVECTION WILL FIZZLE BEFORE CROSSING THE
WI/IL BORDER. HOWEVER...GIVEN A LAKE BREEZE IS LIKELY TO DEVELOP
TOMORROW AFTERNOON...KEPT THE CHANCE OF CONVECTION ALONG THE
LAKESHORE LATE TOMORROW AFTERNOON. A LAKE BREEZE IS ALSO LIKELY
THURSDAY AFTERNOON. BOTH OF THESE LAKE BREEZES COULD PROVIDE LATE
DAY RELIEF FROM THE HEAT...BUT AS OF RIGHT NOW BOTH ARE EXPECTED TO
DEVELOP AFTER DOWNTOWN HITS ITS MAX TEMP.
EXTENDED...FRIDAY THROUGH MONDAY...
THE EXTENDED FEATURES A TRANSITION FROM THE PERSISTENT UPPER LEVEL
RIDGE TO UPPER LEVEL NORTHWEST FLOW. THE OPPRESSIVE HEAT CONTINUES
THROUGH THE EARLY PART OF THE WEEKEND WITH RELIEF ARRIVING IN THE
FORM OF A BACKDOOR COLD FRONT. THE TIMING OF THIS COLD FRONT IS
DEBATABLE WITH THE MODELS DIFFERING ON ITS ARRIVAL. LEANING TOWARD
THE ECMWF/S STEADY SOLUTION WHICH FEATURES THE COLD FRONT MOVING IN
SUNDAY NIGHT INTO MONDAY MORNING. AS SUCH...RAISED ALLBLEND TEMPS
ON SATURDAY. LOOKING AT TEMPS AT OR JUST ABOVE 100 DEGREES ON
FRIDAY...THEN A BIT COOLER WITH MAX TEMPS IN THE UPPER 80S TO MID
90S. IF TRENDS CONTINUE TO LEAN TOWARD THE ECMWF...EXPECTING FUTURE
FORECASTS TO RAISE TEMPS EVEN FURTHER ON BOTH FRIDAY AND
SATURDAY...WITH SATURDAY MOST LIKELY REMAINING COOLER THAN FRIDAY.
ONCE AGAIN...TEMPS AND PRECIP ALL DEPEND ON THE TIMING OF THIS
FRONT. LEANED TOWARD THE ECMWF WITH THE EXTENDED PRECIP
FORECAST...BUT TO BLEND WELL WITH THE NEIGHBORS AND GIVEN HOW FAR
OUT THE FORECAST PERIOD IS...BLENDED IN A LITTLE OF THE GFS. SUNDAY
NIGHT AND MONDAY LOOK LIKE THE BEST CHANCES OF PRECIP AS THE FRONT
SINKS SOUTH THROUGH THE CWA. TEMPS BEHIND THE FROPA LOOK NEAR
NORMAL.
JEE
&&
.CLIMATE...
520 AM CDT
CHICAGO ROCKFORD
HIGH LOW HIGH LOW
TUE 102 78 99 74
1949 1911 1925 1911
WED 102 80 101 77
1911 1921 1911 1977
THU 102 82 100 77
1911 1911 1911 1911
FRI 99 80 102 73
1988 1977 1936 1948
THE ALL TIME RECORD HIGH FOR CHICAGO IS 105 SET BACK ON JULY 24
1934...AND FOR ROCKFORD IS 112 SET ON JULY 14 1936.
IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 22Z...
* SLIGHT THREAT OF TS LATE AFTERNOON-MID EVENING.
TRS
//DISCUSSION...UPDATED 20Z...
A SHORT WAVE MOVING ACROSS CENTRAL TOWARD EAST CENTRAL WI AT MID
AFTERNOON WAS GENERATING SOME PATCHES OF ALTOCUMULUS...INDICATING
AT LEAST MID LEVEL LIFT. NON-IMPRESSIVE CU FIELD ACROSS SOUTHERN
WI WILL NEED TO BE MONITORED FOR ANY SIGNS OF ENHANCEMENT AS THE
SHORT WAVE CONTINUES TO THE ESE. BEST AREA FOR CONVECTIVE
INITIATION LOOKS TO BE IN E CENTRAL AND PORTIONS OF SE WI DURING
LATE AFTERNOON. STEERING FLOW WOULD THEN TAKE ANY CELLS
SOUTHEASTWARD OUT OVER THE LAKE...UNLESS TS FIRE SOONER /FURTHER
W/ THAN CURRENTLY EXPECTED THEN POTENTIALLY COULD MAKE IT TO THE
FAR NE CORNER OF IL.
TRS
PREVIOUS DISCUSSION...UPDATED 18Z...
THE OUTFLOW BOUNDARY THAT WAS GENERATED BY THUNDERSTORMS THAT
OCCURRED OVER PARTS OF SOUTHERN WI DURING THE FIRST PART OF THE
MORNING WEAKENED AS IT MOVED SOUTH INTO NORTHERN IL. BY 17Z IT
HAD HAD PRETTY MUCH WASHED OUT WITH MOST METARS AND MESONET OBS
SHOWING SURFACE WINDS RETURNING TO LIGHT SSW-SW.
CONVECTIVE TEMPERATURE IS ABOUT 93F AND NOT REACHED YET SO
CUMULUS HAS NOT MADE AN APPEARANCE OVER THE AREA YET. MOST OF THE
DEBRIS CLOUDS FROM THE WI THUNDERSTORMS HAS THINNED CONSIDERABLY
SO GOOD SURFACE HEATING DURING THE FIRST PART OF THE AFTERNOON
SHOULD RAISE TEMPERATURES ENOUGH TO POP CUMULUS 20-21Z.
HOWEVER...WITHOUT ANY SURFACE FEATURE IN THE AREA TO FOCUS LOW
LEVEL CONVERGENCE NOR ANY MID OR UPPER LEVEL DISTURBANCES...AS
WELL AS A SLIGHT WARMING OF MID LEVELS...CHANCES OF ANYTHING
MORE THAN AN ISOLATED THUNDERSTORM DURING THE LATER AFTERNOON OR
THIS EVENING LOOKS TO BE VERY LOW.
A SIGNIFICANT SHORT WAVE IS UPSTREAM...CURRENTLY MOVING OVER THE
DAKOTAS...BUT WITH THE UPPER RIDGE TO REBUILD OVER THE LOCAL AREA
BETWEEN THE SOUTHERN END OF A SHORT WAVE TROUGH MOVING FURTHER E
ACROSS THE NORTHERN GREAT LAKES AND THE NORTHERN PLAINS SHORT
WAVE MOVING E FROM THE NORTHERN PLAINS TOWARD SOUTHERN MANITOBA
AND NORTHWEST MN OVERNIGHT AND WED MORNING...DO NOT SEE ANY
PARTICULAR TIME FRAME WHEN CHANCES WOULD BE HIGH ENOUGH FOR
MENTION IN THE TAFORS.
TRS
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE IN ALL ELEMENTS THIS AFTERNOON AND THIS EVENING.
TRS
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
* WEDNESDAY NIGHT...VFR. SLIGHT CHANCE OF TSRA.
* THURSDAY...VFR.
* FRIDAY...VFR. SLIGHT CHANCE OF TSRA FRIDAY NIGHT.
* SATURDAY...VFR. SLIGHT CHANCE OF TSRA.
&&
.MARINE...
247 PM CDT
LOW PRESSURE PASSING NORTH OF THE LAKES ACROSS ONTARIO THIS EVENING
WILL TRAIL A WEAK COLD FRONT ACROSS THE WESTERN GREAT LAKES LATER
TONIGHT AND WEDNESDAY. THIS FRONT IS EXPECTED TO WASH OUT AS IT
SLIDES DOWN ACROSS CENTRAL AND SOUTHERN LAKE MICHIGAN WEDNESDAY...
WITH THE FRONT REDEVELOPING BACK TO THE NORTH IN RESPONSE TO ANOTHER
LOW MOVING ACROSS SASKATCHEWAN AND MANITOBA. THIS SECOND LOW WILL
MOVE EAST ACROSS NORTHERN ONTARIO AND HUDSON BAY THROUGH THURSDAY
AND WILL DRAG ANOTHER FAIRLY WEAK COLD FRONT ACROSS LAKE MICHIGAN
THURSDAY NIGHT INTO FRIDAY. WHILE THE INITIAL PUSH OF COOLER WILL BE
RATHER MEAGER...HIGH PRESSURE BUILDING ACROSS ONTARIO AND THE
NORTHERN LAKES SATURDAY WILL BRING SLIGHTLY STRONGER NORTH WINDS AND
COOLER AIR ACROSS LAKE MICHIGAN INTO THE WEEKEND.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...HEAT ADVISORY...ILZ014 UNTIL 7 AM WEDNESDAY.
EXCESSIVE HEAT WATCH...ILZ014...7 AM WEDNESDAY TO 9 PM THURSDAY.
HEAT ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-ILZ011-
ILZ012-ILZ013-ILZ019-ILZ020-ILZ021-ILZ022-ILZ023-ILZ032-
ILZ033-ILZ039 UNTIL 9 PM THURSDAY.
IN...HEAT ADVISORY...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 9 PM
THURSDAY.
LM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
328 PM CDT TUE JUL 3 2012
.SYNOPSIS...
12Z UA ANALYSIS HAD AN 850MB LOW IN NORTHWEST SOUTH DAKOTA WITH A
WARM FRONT INTO SOUTHWEST MINNESOTA. AN INFERRED BOUNDARY RAN
ALONG THE MN/IA BORDER AND INTO SOUTHERN WISCONSIN. DEW POINTS ON
THIS BOUNDARY WERE IN THE MID TEENS. A DECAYING LLJ RAN FROM WEST
TEXAS INTO SOUTHWEST IOWA THAT WAS IN AN AXIS OF MID TEEN DEW
POINTS AS WELL. SATELLITE TRENDS THROUGH MID AFTERNOON SHOW
DIURNAL CU TRYING TO DEVELOP IN THE REMNANT COLD POOL OF LAST
NIGHTS MCS IN WISCONSIN AND FROM MISSOURI INTO ILLINOIS.
18Z SFC ANALYSIS HAS A LOW AT KMHE AND ANOTHER IN NORTHEAST SOUTH
DAKOTA. AN IMPLIED BOUNDARY RAN SOUTHEAST INTO NORTHEAST IOWA WITH
ANOTHER IMPLIED BOUNDARY FROM WESTERN WISCONSIN INTO NORTHEAST
ILLINOIS. DEW POINTS WERE IN THE LOW 70S ACROSS THE MID
MISSISSIPPI VALLEY WITH GENERALLY 60S ELSEWHERE.
&&
.SHORT TERM...TONIGHT AND WEDNESDAY
THE CLOUD COVER FROM THE NOCTURNAL MCS IS HOLDING TEMPERATURES
DOWN COMPARED TO YESTERDAY. AS A RESULT...THE HEAT ADVISORY IS
JUST BARELY VERIFYING AT MID AFTERNOON.
DEW POINTS HAVE BEEN INTERESTING. TODAY AND YESTERDAY DEW POINTS
HAVE RISEN DURING THE DAY AND THEN DROPPED AT NIGHT. THE ONLY
EXPLANATION THAT MAKES SENSE FOR THIS OCCURRING IS CORN. ONCE THE
SUN COMES UP THE CORN STARTS TO ACTIVELY EVAPOTRANSPIRATE. WITH
SUNSET THE EVAPOTRANSPIRATION SHUTS DOWN.
THEREFORE...WILL GO WITH THE IDEA OF DEW POINTS DROPPING TONIGHT
AND THEN INCREASING DURING THE DAY ON WEDNESDAY.
THE CU DEVELOPMENT ACROSS WISCONSIN AND MISSOURI INTO CENTRAL
ILLINOIS SO FAR HAS NOT SHOWN MUCH ADDITIONAL DEVELOPMENT. THESE
DIURNAL CLOUDS WILL HAVE TO BE WATCHED CAREFULLY FOR FURTHER
DEVELOPMENT THROUGH LATE AFTERNOON. BASED ON RAP TRENDS...
CONVECTION MAY STILL BE POSSIBLE FROM MID TO LATE AFTERNOON AND
INTO THE EARLY EVENING JUST OUTSIDE OF THE CWFA.
A BIGGER QUESTION IS WHAT HAPPENS LATER TONIGHT. SATELLITE HAS A
VERY SUBTLE WAVE MOVING INTO SOUTHWEST MINNESOTA WITH POSSIBLY
ANOTHER BACK IN THE DAKOTAS. RAP TRENDS SHOW THESE FEATURES IN THE
500MB FLOW. THE PROXIMITY OF A SFC LOW IN EASTERN SOUTH DAKOTA
COMBINED WITH THE LLJ INCREASING IN THE PLAINS THIS EVENING SHOULD
BE JUST ENOUGH TO INITIATE ANOTHER NOCTURNAL MCS. THE LLJ IS
WEAKER OVER THE CWFA SO THE MCS SHOULD MOVE GENERALLY EAST ACROSS
MINNESOTA INTO WISCONSIN. OUTFLOW FROM THIS MCS WILL LIKELY
GENERATE NEW CONVECTION THAT WILL DECAY AND DISSIPATE ALONG THE
NORTHERN CWFA BORDER LIKE THIS MORNING. DEBRIS CLOUDS THEN PLAY
INTO TEMPERATURES ON WEDNESDAY.
ON WEDNESDAY...WILL GO THE THE IDEA THAT DEBRIS CLOUDS FROM
NOCTURNAL CONVECTION WILL INITIALLY HOLD TEMPERATURES BACK UNTIL
IT THINS BY MID TO LATE MORNING. ASSUMING THIS SCENARIO IS
CORRECT...MAX TEMPERATURES MAY ONLY BE SLIGHTLY WARMER WEDNESDAY
THAN THEY ARE TODAY.
REGARDING HEADLINES...WILL CONTINUE WITH THE HEAT ADVISORY. IF DEW
POINTS DROP TONIGHT AS THEY HAVE THE PREVIOUS TWO NIGHTS...HEAT
INDEX VALUES MAY DROP INTO THE MID 70S PRIOR TO SUNRISE. GIVEN THE
LENGTH OF TIME THE HEAT IS EXPECTED TO BE AROUND...THE HEAT
ADVISORY WILL LIKELY TRANSITION INTO AN EXCESSIVE HEAT WARNING
POSSIBLY AS EARLY AS WEDNESDAY. ..08..
.LONG TERM...WEDNESDAY NIGHT THROUGH NEXT TUESDAY
FOCUS REMAINS ON THE EXTENDED PERIOD OF HIGH HEAT AND HUMIDITY.
PATTERN CHANGE OVER THE WEEKEND LOOKS TO BRING SOME RELIEF IN THE
FORM OF RAIN CHANCES AND SLIGHTLY COOLER TEMPERATURES.
THE STAGNANT WEATHER PATTERN RESULTING FROM AN UPPER RIDGE AND HEAT
DOME OVER THE CENTRAL U.S. WILL CHANGE LITTLE THROUGH THE REST OF
THE WORKWEEK. LOCALLY...THE HEAT AND HIGH HEAT INDEX READINGS WILL
WORSEN AS AN EASTWARD SHIFT IN THE HIGH CENTER SENDS THE DOME OF
HEAT ALOFT NORTHEAST FROM THE PLAINS. USING A MIDDLE OF THE ROAD
ECM GUIDANCE...WHICH IS BETWEEN THE TOO WARM NAM AND TOO COOL
TRENDING GFS...BY THURSDAY 850 MB TEMPERATURES ARE EXPECTED TO CLIMB
ABOUT 4 TO 5 DEGREES C WARMER THAN THIS MORNING...AND 925 MB
TEMPERATURES AROUND 6 TO 7 DEGREES C WARMER. THIS WOULD EASILY DRIVE
MAX TEMPERATURES INTO THE 100 TO 105 RANGE...HOWEVER...SURFACE
DEWPOINTS AND LOW LEVEL MOISTURE FEEDBACK ON TEMPERATURES REMAINS
PROBLEMATIC. EVAPOTRANSPIRATION FROM MATURING FIELD CROPS APPEARS TO
BE THE CULPRIT FOR DEWPOINTS CLIMBING INTO THE 70S DURING WEAK
MIXING AT NIGHT...WHICH TODAY ARE REMAINING HIGH DESPITE 10 TO 20 KT
WINDS. MODELS WILL NOT LIKELY HANDLE THIS FEEDBACK PROPERLY AND THUS
THE DRIER NAM WITH ITS LOWER DEWPOINTS AND WIDESPREAD 104 TO 107 MAX
TEMPERATURE RANGE FOR THU IS SUSPECT...WHILE THE EQUALLY TOO MOIST
TRENDING GFS IS TOO COOL AND UNUSABLE. FOLLOWING MORE CLOSELY THE
BIAS CORRECTED MODELS AND 12Z ECM...HAVE KEPT THU AS THE WARMEST OF
THE STRETCH WITH A COMPROMISE 99 TO 102 RANGE FOR HIGHS. USING TODAY AS
A MODEL...HAVE KEPT DEWPOINTS RELATIVELY HIGH IN THE UPPER 60S TO
LOWER 70S...WHICH WOULD RESULT IN HEAT INDEX READINGS INTO A 105 TO
110 RANGE IN THE AFTERNOON INTO EARLY EVENING. THIS WOULD BE WELL
INTO EXCESSIVE HEAT WARNING CRITERIA...HOWEVER...DUE TO LOW
CONFIDENCE IN THESE CRITICAL DEWPOINT VALUES...WILL HOLD OFF ON A
WARNING AS THE HEAT ADVISORY IS ALREADY IN PLACE FOR THESE PERIODS.
SLIGHT COOLING ALOFT IS NOTED FOR FRIDAY AND MODELS DROP A WEAK
FRONT SOUTH TOWARD THE FAR NORTHERN FORECAST AREA BY LATE IN THE
DAY. HAVE THUS LIMITED HIGHS TO THE 90S...WHILE HEAT INDICES AGAIN
PUSH TO AT LEAST 100 TO 105. OVERNIGHT TEMPERATURES FROM WED NIGHT
THROUGH AT LEAST FRIDAY NIGHT WILL BE IN THE 70S...CONTINUING AN
EXTENDED PERIOD OF HIGH HEAT INDICES ALSO SUPPORTING THE ON-GOING
ADVISORY.
SATURDAY THROUGH TUESDAY...THE UPPER RIDGE BEGINS TO BREAK DOWN AS A
TROUGH DEVELOPS OVER THE EASTERN U.S. AND AN NEW UPSTREAM RIDGE
BUILDS OVER THE ROCKIES. THE RESULTING NW FLOW ALOFT WILL ALLOW THE
MORE ACTIVE FRONTAL ZONE TO DROP SOUTH AND AFFECT THE
AREA...RESULTING IN AN EXTENDED PERIOD OF LOW POPS FOR RAIN AND
THUNDERSTORMS...ALONG WITH PROGRESSIVELY COOLER TEMPERATURES.
SHEETS
&&
.AVIATION... /ISSUED 1222 PM CDT TUE JUL 3 2012/
VFR WX IS EXPECTED THROUGH 00Z/05. HIGH DENSITY ALTITUDES AOA 3KFT
CAN BE EXPECTED 18Z/03 THROUGH 02Z/04 AND AGAIN AFT 16Z/04.
BOUNDARIES FROM THE OVERNIGHT TSRA MAY BE A FOCUS FOR DIURNAL
CONVECTION 20Z/03 TO 03Z/04. HOWEVER...THE PROBABILITY OF A SHRA
OR TSRA HITTING ANY TAF SITE IS 10 PERCENT OR LESS AND WAS NOT
INCLUDED IN THE 18Z TAFS. NOCTURNAL CONVECTION TONIGHT SHOULD
REMAIN ACROSS MINNESOTA/WISCONSIN. ..08..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...HEAT ADVISORY UNTIL 7 AM CDT SATURDAY 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...HEAT ADVISORY UNTIL 7 AM CDT SATURDAY FOR BUREAU-CARROLL-HANCOCK-
HENDERSON-HENRY IL-JO DAVIESS-MCDONOUGH-MERCER-PUTNAM-ROCK
ISLAND-STEPHENSON-WARREN-WHITESIDE.
MO...HEAT ADVISORY UNTIL 7 AM CDT SATURDAY FOR CLARK-SCOTLAND.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1222 PM CDT TUE JUL 3 2012
.AVIATION...
VFR WX IS EXPECTED THROUGH 00Z/05. HIGH DENSITY ALTITUDES AOA 3KFT
CAN BE EXPECTED 18Z/03 THROUGH 02Z/04 AND AGAIN AFT 16Z/04.
BOUNDARIES FROM THE OVERNIGHT TSRA MAY BE A FOCUS FOR DIURNAL
CONVECTION 20Z/03 TO 03Z/04. HOWEVER...THE PROBABILITY OF A SHRA
OR TSRA HITTING ANY TAF SITE IS 10 PERCENT OR LESS AND WAS NOT
INCLUDED IN THE 18Z TAFS. NOCTURNAL CONVECTION TONIGHT SHOULD
REMAIN ACROSS MINNESOTA/WISCONSIN. ..08..
&&
.PREV DISCUSSION... /ISSUED 1100 AM CDT TUE JUL 3 2012/
UPDATE...
SOME IMPORTANT UPDATES HAVE BEEN DONE TO THE FCST.
THE NOCTURNAL CONVECTION FROM THE MCS HAS ESSENTIALLY DISSIPATED
AS THE LLJ CONTINUES TO WEAKEN. THE CONVECTION THAT WAS INITIALLY
ALONG THE MN/IA BORDER A COUPLE OF HOURS AGO WAS BEING SUPPORTED
BY A THETA E GRADIENT BUT RAP TRENDS INDICATE THAT WILL CONTINUE
TO WEAKEN OVER THE NEXT SEVERAL HOURS.
LOOKING AT THE 15Z SFC OBS ONE CAN PICK OUT TWO DISTINCT
BOUNDARIES LEFT OVER FROM THE NOCTURNAL CONVECTION...ONE ROUGHLY
ALONG HWY 30 AND THE OTHER ALONG HWY 20. THESE BOUNDARIES COMBINED
WITH THE CLOUDS WILL SUPPRESS TEMPERATURES ACROSS THE NORTHERN
CWFA THIS AFTERNOON. IF DEW POINTS WOULD MIX OUT A BIT MORE THEN
THE HEAT ADVISORY MAY BE MARGINAL IN THIS AREA.
ACROSS THE REMAINDER OF THE AREA THE HEAT ADVISORY WILL BE
REALIZED BUT TEMPERATURES MAY NOT GET AS WARM AS EXPECTED DUE TO
THE CLOUDS. HOWEVER...THERE IS WAA ALOFT TAKING PLACE SO THIS MAY
BE ENOUGH TO OFFSET THE CLOUDS.
SO...THE REMAINDER OF THE MORNING AND EARLY AFTERNOON HOURS WILL
BE DRY. THE QUESTION IS WHETHER OR NOT THE OUTFLOW BOUNDARIES FROM
THE NOCTURNAL CONVECTION WILL BECOME EFFECTIVE BOUNDARIES TO HELP
INITIATE DIURNAL CONVECTION BY MID TO LATE AFTERNOON AND POSSIBLY
INTO THE EVENING HOURS. THIS IS A POSSIBILITY AS THE 12Z DVN
SOUNDING HAS A CONVECTIVE TEMPERATURE OF 96. HOWEVER...WAA ALOFT
THROUGH THE AFTERNOON SHOULD RAISE THIS CLOSER TO OR ABOVE 100.
INTERNALLY...THE MCS AND LIFT TOOLS ARE MIXED. TRENDS FROM THE RAP
SUGGEST A THETA E GRADIENT DEVELOPING ACROSS EASTERN WISCONSIN
THAT SLOWLY MOVES SOUTHWEST INTO ILLINOIS AND THE FAR
EAST/NORTHEAST PARTS OF THE CWFA. THERE IS RESPECTABLE FORCING ON
THE 340K SFC WITH THIS FEATURE.
RIGHT NOW THE DRY FCST WILL CONTINUE THROUGH LATE AFTERNOON.
HOWEVER...I WOULD NOT BE COMPLETELY SURPRISED IF DIURNAL
CONVECTION WOULD DEVELOP JUST OUTSIDE OF THE CWFA. ..08..
PREV DISCUSSION... /ISSUED 324 AM CDT TUE JUL 3 2012/
SYNOPSIS...
WARM AND MUGGY CONDITIONS CONTINUE ACROSS THE FORECAST AREA THIS
MORNING. A STRONG TO SEVERE MCS IS UNDERWAY OVER MINNESOTA AND
WISCONSIN...HAVING FIRED EARLIER IN THE EVENING ALONG A WARM FRONT
BOUNDARY DRAPED FROM A SURFACE LOW IN CENTRAL SOUTH DAKOTA ACROSS
NORTHERN MINNESOTA AND NORTHERN WISCONSIN. CORFIDI VECTORS AS WELL
AS MID LEVEL FLOW SHOWS THIS MCS WILL CONTINUE IN ITS EAST-SOUTHEAST
DIRECTION...AFFECTING PORTIONS OF OF SOUTHERN MINNESOTA AND CENTRAL
WISCONSIN EARLY THIS MORNING. DECREASING INSTABILITY AND
INCREASING INHIBITION TO THE EAST SHOULD WEAKEN IT SIGNIFICANTLY
BY THE TIME IT REACHES SOUTHEAST MN. CONTINUED LIGHT SOUTH WINDS
ACROSS THE FORECAST AREA ARE KEEPING TEMPERATURES AND DEWPOINTS
WARM...WITH MID-UPPER 70 TEMPS NEARLY EVERYWHERE WITH DEWPOINTS IN
THE MID 60S TO AROUND 70. LE
SHORT TERM...TODAY AND TONIGHT...
VERY TOUGH FORECAST TODAY WITH SIGNIFICANT HEAT CONCERNS.
TEMPERATURES AND HEAT INDICES CLOSE TO ADVISORY/WARNING CRITERIA
BEGINS TODAY. TEMPERATURES MONDAY WERE IN THE 93-97 RANGE NEARLY
EVERYWHERE...WITH A FEW WARMER/COOLER VALUES HERE AN THERE. THE
AIRMASS WILL BE VERY SIMILAR TO YESTERDAY...BUT THE MID LEVEL
TEMPERATURES WILL CONTINUE TO WARM AS THE CONVECTION UP NORTH PUSHES
THE HEAT DOME BACK SOUTH. 925MB TEMPERATURES ARE FORECAST TO RISE
ABOUT 2 DEGREES OVER YESTERDAY...AS ARE 850MB TEMPERATURES. WHILE
THIS DOESNT EXACTLY TRANSLATE DOWN TO THE SURFACE...HAVE GENERALLY
RAISED TODAYS HIGH TEMPS ABOUT 2 DEGREES OVER YESTERDAY. GUIDANCE
HAS BEEN STRUGGLING WITH TEMPS AND DEWPOINTS LATELY...AND HAVE PUT
MORE WEIGHT ON THIS TYPE OF ADJUSTMENT THAN ON ANY ONE GUIDANCE
PRODUCT. DEWPOINTS ARE ALSO A DIFFICULT FORECAST TODAY AS A SMALL
CHANGE PUTS US INTO EXCESSIVE HEAT WARNING CRITERIA INSTEAD OF HEAT
ADVISORY. DEWPOINTS YESTERDAY WERE GENERALLY IN THE UPPER 60S TO
VERY LOW 70S. THERE IS LITTLE CHANGE IN THE AIRMASS TO CAUSE THESE
TO CHANGE...AS THERE HAS NOT BEEN MUCH RECENT RAINFALL TO CAUSE THEM
TO RISE...BUT WE ARE NOT SO DRY THAT THEY WILL LOWER WITH TIME.
THERE IS ALSO ENOUGH LOW LEVEL MOISTURE BEING ADVECTED INTO THE AREA
FROM THE SOUTH TO HELP KEEP THEM UP AS WELL. THUS...HAVE GONE WITH
VERY SIMILAR DEWPOINTS TO YESTERDAY. THIS DOES PUT US VERY CLOSE TO
HEAT WARNING CRITERIA...AND LIKELY SOME LOCATIONS WILL HIT 105F OR
HIGHER TODAY...BUT SHOULD NOT BE WIDESPREAD ENOUGH TO TRIGGER THE
WARNING JUST YET. ALSO...WE ARE DROPPING BELOW 75 THIS MORNING OVER
ENOUGH OF THE AREA THAT TODAY WOULD BE THE FIRST DAY OF POSSIBLE
HEAT WARNING CRITERIA. THUS...AM STAYING WITH THE HEAT ADVISORY
NOW...BUT IF TODAYS DEWPOINTS OR TEMPERATURES ARE COMING IN HIGHER
THAN FORECAST AN UPGRADE MAY BE NEEDED. THE PUDDLE OF MOISTURE AND
CONVERGENCE THAT TRIGGERED THE THUNDERSTORMS IN OUR SOUTHEAST MONDAY
EVENING SHOULD SETTLE BACK TO OUR SOUTH...AND DO NOT ANTICIPATE A
REPEAT THIS AFTERNOON. THUS...A DRY FORECAST FOR THIS AFTERNOON AND
EVENING.
TONIGHT WILL BE ANOTHER WARM AND MUGGY ONE WITH TEMPERATURES ONLY
FALLING INTO THE MID 70S. ANOTHER MCS MAY FIRE ACROSS SOUTHERN
MINNESOTA TO PUSH SOME CLOUDS OUR DIRECTION. THE WARM FRONT WILL BE
SAGGING BACK INTO SOUTHERN MINNESOTA OVERNIGHT...SO ANTICIPATE THAT
POOLING ALONG THIS BOUNDARY WILL CAUSE WARMER DEWPOINTS OVERNIGHT TO
AID IN KEEPING TEMPERATURES WARMER...AND KEEPING THE HUMIDITY UP.
NONE OF THIS MCS ACTIVITY SHOULD REACH THE FORECAST AREA.
LE
LONG TERM...WEDNESDAY THROUGH MONDAY...
BARRING ANY UNFORESEEN MCS IN OR NEAR THE CWA OR AT THE VERY LEAST
CLOUD DEBRIS MUCH OF THIS PERIOD EXPECTED TO BE A SCORCHER.
INDEPENDENCE DAY THROUGH FRIDAY...HEAT DOME CENTERED OVER IA TO
PROVIDE HOT AND HUMID CONDITIONS WITH AN EXCESSIVE HEAT WARNING
HEADLINE MOST LIKELY NEEDED ALL THREE DAYS. ONCE AGAIN THIS IS
ASSUMING THE DVN CWA IS NOT IMPACTED BY AN UNFORESEEN MCS. OTHERWISE
MAXIMUM TEMPERATURES TO BE AROUND 100 DURING THE AFTERNOON AT MOST
LOCATIONS THIS PERIOD. DEWPOINTS WILL BE NEAR 70 DURING THE
AFTERNOON JUMPING INTO THE MID 70S IN THE EVENING DUE TO THE
EVAPOTRANSPIRATION REACHING A PEAK IN THE EVENING. THIS WILL YIELD
HEAT INDEX VALUES OF 105 TO 110 AT MOST LOCATIONS DURING THE
AFTERNOON AND EVENING...MORE THAN ENOUGH TO VERIFY A HEAT WARNING.
BECAUSE HEAT HAS AN ACCUMULATIVE EFFECT ON THE BODY THIS EXTENDED
HOT WEATHER WILL BECOME INCREASINGLY DETRIMENTAL FOR ANYONE WITHOUT
AIR CONDITIONING OR WORKING OUTDOORS FOR PROLONGED PERIODS OF TIME.
NIGHTTIME WILL OFFER LITTLE OR NO RELIEF AS MIN TEMPS WILL BE IN THE
MID TO UPPER 70S...WITH HEAT INDEX VALUES REMAINING ABOVE 80 FOR
MUCH OF THE NIGHT.
FRIDAY NIGHT THROUGH MONDAY...OPERATIONAL MODELS CONTINUE TO
STRUGGLE WITH THE TIMING OF THE COLD FRONT DROPPING DOWN FROM THE
NORTH. THE GFS REMAINS CONSISTENT WITH THE FRONT ARRIVING BY
SATURDAY AND THEN STALLING ACROSS THE DVN CWA THROUGH THE WEEKEND
ALLOWING FOR REPEATED MCS ACTIVITY...MOST LIKELY SEVERE. THE ECM
SHOWS THE FRONT NOT ARRIVING UNTIL LATER SUNDAY OR SUNDAY NIGHT. THE
GEM IS SIMILAR TO THE GFS. FOR NOW WILL KEEP THE ENTIRE CWA IN THE
90S ON SATURDAY DROPPING INTO THE 80S BY MONDAY. HOWEVER THESE
READINGS MAY NEED TO BE ADJUSTED DEPENDING ON WHEN THE FRONT
ACTUALLY ARRIVES.
NEXT WEEK...RELIEF FROM THE HEAT EXPECTED FOR MUCH OF NEXT WEEK AS
THE NORTH ATLANTIC/ARCTIC OSCILLATION ANOMALIES GO NEGATIVE. THIS
ALLOWS FOR A DEEPENING TROUGH IN THE GREAT LAKES/EASTERN CANADA TO
SET UP SHOP. THIS PUTS THE MIDWEST IN A NORTHWEST FLOW WITH MAX
TEMPS CLOSER TO NORMAL...IN THE 80S.
HAASE
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...HEAT ADVISORY UNTIL 7 AM CDT SATURDAY 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...HEAT ADVISORY UNTIL 7 AM CDT SATURDAY FOR BUREAU-CARROLL-HANCOCK-
HENDERSON-HENRY IL-JO DAVIESS-MCDONOUGH-MERCER-PUTNAM-ROCK
ISLAND-STEPHENSON-WARREN-WHITESIDE.
MO...HEAT ADVISORY UNTIL 7 AM CDT SATURDAY FOR CLARK-SCOTLAND.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1100 AM CDT TUE JUL 3 2012
.UPDATE...
SOME IMPORTANT UPDATES HAVE BEEN DONE TO THE FCST.
THE NOCTURNAL CONVECTION FROM THE MCS HAS ESSENTIALLY DISSIPATED
AS THE LLJ CONTINUES TO WEAKEN. THE CONVECTION THAT WAS INITIALLY
ALONG THE MN/IA BORDER A COUPLE OF HOURS AGO WAS BEING SUPPORTED
BY A THETA E GRADIENT BUT RAP TRENDS INDICATE THAT WILL CONTINUE
TO WEAKEN OVER THE NEXT SEVERAL HOURS.
LOOKING AT THE 15Z SFC OBS ONE CAN PICK OUT TWO DISTINCT
BOUNDARIES LEFT OVER FROM THE NOCTURNAL CONVECTION...ONE ROUGHLY
ALONG HWY 30 AND THE OTHER ALONG HWY 20. THESE BOUNDARIES COMBINED
WITH THE CLOUDS WILL SUPPRESS TEMPERATURES ACROSS THE NORTHERN
CWFA THIS AFTERNOON. IF DEW POINTS WOULD MIX OUT A BIT MORE THEN
THE HEAT ADVISORY MAY BE MARGINAL IN THIS AREA.
ACROSS THE REMAINDER OF THE AREA THE HEAT ADVISORY WILL BE
REALIZED BUT TEMPERATURES MAY NOT GET AS WARM AS EXPECTED DUE TO
THE CLOUDS. HOWEVER...THERE IS WAA ALOFT TAKING PLACE SO THIS MAY
BE ENOUGH TO OFFSET THE CLOUDS.
SO...THE REMAINDER OF THE MORNING AND EARLY AFTERNOON HOURS WILL
BE DRY. THE QUESTION IS WHETHER OR NOT THE OUTFLOW BOUNDARIES FROM
THE NOCTURNAL CONVECTION WILL BECOME EFFECTIVE BOUNDARIES TO HELP
INITIATE DIURNAL CONVECTION BY MID TO LATE AFTERNOON AND POSSIBLY
INTO THE EVENING HOURS. THIS IS A POSSIBILITY AS THE 12Z DVN
SOUNDING HAS A CONVECTIVE TEMPERATURE OF 96. HOWEVER...WAA ALOFT
THROUGH THE AFTERNOON SHOULD RAISE THIS CLOSER TO OR ABOVE 100.
INTERNALLY...THE MCS AND LIFT TOOLS ARE MIXED. TRENDS FROM THE RAP
SUGGEST A THETA E GRADIENT DEVELOPING ACROSS EASTERN WISCONSIN
THAT SLOWLY MOVES SOUTHWEST INTO ILLINOIS AND THE FAR
EAST/NORTHEAST PARTS OF THE CWFA. THERE IS RESPECTABLE FORCING ON
THE 340K SFC WITH THIS FEATURE.
RIGHT NOW THE DRY FCST WILL CONTINUE THROUGH LATE AFTERNOON.
HOWEVER...I WOULD NOT BE COMPLETELY SURPRISED IF DIURNAL
CONVECTION WOULD DEVELOP JUST OUTSIDE OF THE CWFA. ..08..
&&
.PREV DISCUSSION... /ISSUED 653 AM CDT TUE JUL 3 2012/
AVIATION...
VFR CONDITIONS CONTINUE TODAY WITH RIDGE OF HIGH PRESSURE OVER
THE MIDWEST. THE VERY HOT CONDITIONS WILL LIKELY PRODUCE DENSITY
ALTITUDE ISSUES TODAY. IN FACT...AT KMLI THE DENSITY ALTITUDE THIS
AFTERNOON WILL LIKELY BE OVER 3000FT. WINDS WILL GENERALLY BE FROM
THE SOUTH/SOUTHWEST...AND INCREASE TO 10-14 KNOTS DURING THE
DAY...THEN DIMINISH AGAIN AFTER 00Z.
PREV DISCUSSION... /ISSUED 324 AM CDT TUE JUL 3 2012/
SYNOPSIS...
WARM AND MUGGY CONDITIONS CONTINUE ACROSS THE FORECAST AREA THIS
MORNING. A STRONG TO SEVERE MCS IS UNDERWAY OVER MINNESOTA AND
WISCONSIN...HAVING FIRED EARLIER IN THE EVENING ALONG A WARM FRONT
BOUNDARY DRAPED FROM A SURFACE LOW IN CENTRAL SOUTH DAKOTA ACROSS
NORTHERN MINNESOTA AND NORTHERN WISCONSIN. CORFIDI VECTORS AS WELL
AS MID LEVEL FLOW SHOWS THIS MCS WILL CONTINUE IN ITS EAST-SOUTHEAST
DIRECTION...AFFECTING PORTIONS OF OF SOUTHERN MINNESOTA AND CENTRAL
WISCONSIN EARLY THIS MORNING. DECREASING INSTABILITY AND
INCREASING INHIBITION TO THE EAST SHOULD WEAKEN IT SIGNIFICANTLY
BY THE TIME IT REACHES SOUTHEAST MN. CONTINUED LIGHT SOUTH WINDS
ACROSS THE FORECAST AREA ARE KEEPING TEMPERATURES AND DEWPOINTS
WARM...WITH MID-UPPER 70 TEMPS NEARLY EVERYWHERE WITH DEWPOINTS IN
THE MID 60S TO AROUND 70. LE
SHORT TERM...TODAY AND TONIGHT...
VERY TOUGH FORECAST TODAY WITH SIGNIFICANT HEAT CONCERNS.
TEMPERATURES AND HEAT INDICES CLOSE TO ADVISORY/WARNING CRITERIA
BEGINS TODAY. TEMPERATURES MONDAY WERE IN THE 93-97 RANGE NEARLY
EVERYWHERE...WITH A FEW WARMER/COOLER VALUES HERE AN THERE. THE
AIRMASS WILL BE VERY SIMILAR TO YESTERDAY...BUT THE MID LEVEL
TEMPERATURES WILL CONTINUE TO WARM AS THE CONVECTION UP NORTH PUSHES
THE HEAT DOME BACK SOUTH. 925MB TEMPERATURES ARE FORECAST TO RISE
ABOUT 2 DEGREES OVER YESTERDAY...AS ARE 850MB TEMPERATURES. WHILE
THIS DOESNT EXACTLY TRANSLATE DOWN TO THE SURFACE...HAVE GENERALLY
RAISED TODAYS HIGH TEMPS ABOUT 2 DEGREES OVER YESTERDAY. GUIDANCE
HAS BEEN STRUGGLING WITH TEMPS AND DEWPOINTS LATELY...AND HAVE PUT
MORE WEIGHT ON THIS TYPE OF ADJUSTMENT THAN ON ANY ONE GUIDANCE
PRODUCT. DEWPOINTS ARE ALSO A DIFFICULT FORECAST TODAY AS A SMALL
CHANGE PUTS US INTO EXCESSIVE HEAT WARNING CRITERIA INSTEAD OF HEAT
ADVISORY. DEWPOINTS YESTERDAY WERE GENERALLY IN THE UPPER 60S TO
VERY LOW 70S. THERE IS LITTLE CHANGE IN THE AIRMASS TO CAUSE THESE
TO CHANGE...AS THERE HAS NOT BEEN MUCH RECENT RAINFALL TO CAUSE THEM
TO RISE...BUT WE ARE NOT SO DRY THAT THEY WILL LOWER WITH TIME.
THERE IS ALSO ENOUGH LOW LEVEL MOISTURE BEING ADVECTED INTO THE AREA
FROM THE SOUTH TO HELP KEEP THEM UP AS WELL. THUS...HAVE GONE WITH
VERY SIMILAR DEWPOINTS TO YESTERDAY. THIS DOES PUT US VERY CLOSE TO
HEAT WARNING CRITERIA...AND LIKELY SOME LOCATIONS WILL HIT 105F OR
HIGHER TODAY...BUT SHOULD NOT BE WIDESPREAD ENOUGH TO TRIGGER THE
WARNING JUST YET. ALSO...WE ARE DROPPING BELOW 75 THIS MORNING OVER
ENOUGH OF THE AREA THAT TODAY WOULD BE THE FIRST DAY OF POSSIBLE
HEAT WARNING CRITERIA. THUS...AM STAYING WITH THE HEAT ADVISORY
NOW...BUT IF TODAYS DEWPOINTS OR TEMPERATURES ARE COMING IN HIGHER
THAN FORECAST AN UPGRADE MAY BE NEEDED. THE PUDDLE OF MOISTURE AND
CONVERGENCE THAT TRIGGERED THE THUNDERSTORMS IN OUR SOUTHEAST MONDAY
EVENING SHOULD SETTLE BACK TO OUR SOUTH...AND DO NOT ANTICIPATE A
REPEAT THIS AFTERNOON. THUS...A DRY FORECAST FOR THIS AFTERNOON AND
EVENING.
TONIGHT WILL BE ANOTHER WARM AND MUGGY ONE WITH TEMPERATURES ONLY
FALLING INTO THE MID 70S. ANOTHER MCS MAY FIRE ACROSS SOUTHERN
MINNESOTA TO PUSH SOME CLOUDS OUR DIRECTION. THE WARM FRONT WILL BE
SAGGING BACK INTO SOUTHERN MINNESOTA OVERNIGHT...SO ANTICIPATE THAT
POOLING ALONG THIS BOUNDARY WILL CAUSE WARMER DEWPOINTS OVERNIGHT TO
AID IN KEEPING TEMPERATURES WARMER...AND KEEPING THE HUMIDITY UP.
NONE OF THIS MCS ACTIVITY SHOULD REACH THE FORECAST AREA.
LE
LONG TERM...WEDNESDAY THROUGH MONDAY...
BARRING ANY UNFORESEEN MCS IN OR NEAR THE CWA OR AT THE VERY LEAST
CLOUD DEBRIS MUCH OF THIS PERIOD EXPECTED TO BE A SCORCHER.
INDEPENDENCE DAY THROUGH FRIDAY...HEAT DOME CENTERED OVER IA TO
PROVIDE HOT AND HUMID CONDITIONS WITH AN EXCESSIVE HEAT WARNING
HEADLINE MOST LIKELY NEEDED ALL THREE DAYS. ONCE AGAIN THIS IS
ASSUMING THE DVN CWA IS NOT IMPACTED BY AN UNFORESEEN MCS. OTHERWISE
MAXIMUM TEMPERATURES TO BE AROUND 100 DURING THE AFTERNOON AT MOST
LOCATIONS THIS PERIOD. DEWPOINTS WILL BE NEAR 70 DURING THE
AFTERNOON JUMPING INTO THE MID 70S IN THE EVENING DUE TO THE
EVAPOTRANSPIRATION REACHING A PEAK IN THE EVENING. THIS WILL YIELD
HEAT INDEX VALUES OF 105 TO 110 AT MOST LOCATIONS DURING THE
AFTERNOON AND EVENING...MORE THAN ENOUGH TO VERIFY A HEAT WARNING.
BECAUSE HEAT HAS AN ACCUMULATIVE EFFECT ON THE BODY THIS EXTENDED
HOT WEATHER WILL BECOME INCREASINGLY DETRIMENTAL FOR ANYONE WITHOUT
AIR CONDITIONING OR WORKING OUTDOORS FOR PROLONGED PERIODS OF TIME.
NIGHTTIME WILL OFFER LITTLE OR NO RELIEF AS MIN TEMPS WILL BE IN THE
MID TO UPPER 70S...WITH HEAT INDEX VALUES REMAINING ABOVE 80 FOR
MUCH OF THE NIGHT.
FRIDAY NIGHT THROUGH MONDAY...OPERATIONAL MODELS CONTINUE TO
STRUGGLE WITH THE TIMING OF THE COLD FRONT DROPPING DOWN FROM THE
NORTH. THE GFS REMAINS CONSISTENT WITH THE FRONT ARRIVING BY
SATURDAY AND THEN STALLING ACROSS THE DVN CWA THROUGH THE WEEKEND
ALLOWING FOR REPEATED MCS ACTIVITY...MOST LIKELY SEVERE. THE ECM
SHOWS THE FRONT NOT ARRIVING UNTIL LATER SUNDAY OR SUNDAY NIGHT. THE
GEM IS SIMILAR TO THE GFS. FOR NOW WILL KEEP THE ENTIRE CWA IN THE
90S ON SATURDAY DROPPING INTO THE 80S BY MONDAY. HOWEVER THESE
READINGS MAY NEED TO BE ADJUSTED DEPENDING ON WHEN THE FRONT
ACTUALLY ARRIVES.
NEXT WEEK...RELIEF FROM THE HEAT EXPECTED FOR MUCH OF NEXT WEEK AS
THE NORTH ATLANTIC/ARCTIC OSCILLATION ANOMALIES GO NEGATIVE. THIS
ALLOWS FOR A DEEPENING TROUGH IN THE GREAT LAKES/EASTERN CANADA TO
SET UP SHOP. THIS PUTS THE MIDWEST IN A NORTHWEST FLOW WITH MAX
TEMPS CLOSER TO NORMAL...IN THE 80S.
HAASE
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...HEAT ADVISORY UNTIL 7 AM CDT SATURDAY 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...HEAT ADVISORY UNTIL 7 AM CDT SATURDAY FOR BUREAU-CARROLL-HANCOCK-
HENDERSON-HENRY IL-JO DAVIESS-MCDONOUGH-MERCER-PUTNAM-ROCK
ISLAND-STEPHENSON-WARREN-WHITESIDE.
MO...HEAT ADVISORY UNTIL 7 AM CDT SATURDAY FOR CLARK-SCOTLAND.
&&
$$
AREA FORECAST DISCUSSION
NWS JACKSON KY
135 PM EDT TUE JUL 3 2012
.UPDATE...
ISSUED AT 136 PM EDT TUE JUL 3 2012
ISSUED AN UPDATE TO ACCOUNT FOR TEMPERATURES BEING WARMER THAN
EXPECTED. POPS WERE ADJUSTED TO FOR SHOWERS AND STORMS DEVELOPING IN
THE SOUTH AGAIN. WITH CAPES INCREASING IN THE SOUTH AND THE CAP
WEAKENING...CELLS WILL CONTINUE TO DEVELOP THIS AFTERNOON. WITH
LITTLE ORGANIZATION EXPECTED...WILL HAVE TO WATCH OUT FOR MERGERS AND
CELLS THAT SPLIT. OTHERWISE...JUST SOME RUN OF THE MILL SHOWERS AND
THUNDERSTORMS THIS AFTERNOON. NO ZFP THIS ISSUANCE BUT ONE WILL BE
ISSUED WITH THE 4PM ISSUANCE.
UPDATE ISSUED AT 1006 AM EDT TUE JUL 3 2012
CURRENT RADAR AND VIS IS SHOWING SOME ISOLATED SHOWERS DEVELOPING
ALONG THE I-75 AND ALONG THE HAL ROGERS PARKWAY THIS MORNING AND SO
HAVE UPDATED TO THROW SOME POPS INTO THE MORNING HOURS. MORNING
SOUNDINGS ARE COMING IN A BIT UNSTABLE THIS MORNING AND THESE POPPING
SHOWERS ARE THE RESULT. LOOKS LIKE COVERAGE WILL INCREASE AS THE HEAT
OF THE DAY SETS IN. THIS COUPLED WITH THE NAM AND RUC SHOWING WEAK
UPPER LEVEL SUPPORT CREEPS IN FROM THE WEST. SO ADJUSTED TEMPS AND
CLOUD COVER AND SENT OUT A NEW ZFP.
UPDATE ISSUED AT 741 AM EDT TUE JUL 3 2012
UPDATED SKY COVER GRIDS AND DEW POINTS BASED ON OBSERVED CONDITIONS
EARLY THIS MORNING.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 409 AM EDT TUE JUL 3 2012
A WEAK UPPER TROUGH WILL BE SLOWLY MOVING SOUTHEAST OVER THE REGION
DURING THE PERIOD. IN COMBINATION WITH DIURNAL DESTABILIZATION EACH
DAY...CONVECTION IS EXPECTED TO DEVELOP. WITH FEATURES BEING WEAK...
PRECISELY WHERE IT OCCURS REMAINS TO BE SEEN...AND AT THIS POINT THE
FORECAST WILL DEAL IN GENERALITY. WILL BE USING CHANCE POPS PEAKING
LATE IN THE DAYTIME HOURS. THE NAM HAS INDICATED A CONVECTIVE SYSTEM
MOVING SSW INTO THE AREA LATE WEDNESDAY...AND HAVE USED SLIGHTLY
HIGHER POPS IN OUR NE COUNTIES ON WEDNESDAY. HOWEVER...CONFIDENCE IS
NOT HIGH ENOUGH TO WARRANT A LARGE SPATIAL DIFFERENCE IN POPS.
TEMPS WILL CONTINUE HOT AND NEAR RECORD HIGHS...WITH NO SIGNIFICANT
CHANGE IN AIR MASS.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 400 AM EDT TUE JUL 3 2012
THERE IS GOOD MODEL AGREEMENT WITH THE LONG WAVE PATTERN THROUGH THE
EXTENDED...AS A LARGE RIDGE OF HIGH PRESSURE CENTERED ACROSS THE
CENTRAL CONUS GRADUALLY BUILDS IN ACROSS THE OHIO AND TENNESSEE
VALLEYS...BRINGING REINFORCING HEAT AS WELL AS MAINLY ISOLATED
CONVECTION FROM TIME TO TIME THROUGH THE FIRST PART OF THE
WEEKEND.
BY SUNDAY AND EARLY NEXT WEEK...TROUGHING WILL AMPLIFY ACROSS
THE GREAT LAKES AND NEW ENGLAND. THIS WILL SEND A SURFACE COLD FRONT
SOUTH TOWARDS THE COMMONWEALTH...ALLOWING FOR SOME BETTER CHANCES OF
CONVECTION AS WELL AS COOLER AIR. DETAILS CONTINUE TO BE
CHALLENGING WITH HOW ALL OF THIS UNFOLDS...WITH THE ECMWF SLOWER AND
THE GFS MORE PROGRESSIVE. AS SUCH...HAVE STUCK CLOSE TO A BLEND OF
THE LATEST GUIDANCE AS WELL AS THE INHERITED FORECAST. SATURDAY
LOOKS TO BE THE WARMEST DAY WITH HIGHS IN THE MID TO UPPER 90S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 136 PM EDT TUE JUL 3 2012
VFR CONDITIONS WILL BE EXPECTED THROUGH OUT THE PERIOD. SOME SHOWERS
AND THUNDERSTORMS WILL DEVELOP ACROSS THE AREA SO PUT VCTS IN THE
TAFS FOR THE 21Z TO 01Z PERIOD. DUE TO THE SCATTERED NATURE OF THE
ACTIVITY...WILL GO WITH A VFR OVERNIGHT FOR THE TAF SITES.
HOWEVER...THIS WILL CHANGE SHOULD THEY GET A GOOD RAINFALL.
OTHERWISE...WILL EXPECT MVFR AND IFR OVER RIVER VALLEYS TONIGHT AND
AREAS THAT RECEIVE RAINFALL.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SHALLENBERGER
SHORT TERM...HAL
LONG TERM....GEOGERIAN
AVIATION...SHALLENBERGER
AREA FORECAST DISCUSSION
NWS JACKSON KY
1007 AM EDT TUE JUL 3 2012
.UPDATE...
ISSUED AT 1006 AM EDT TUE JUL 3 2012
CURRENT RADAR AND VIS IS SHOWING SOME ISOLATED SHOWERS DEVELOPING
ALONG THE I-75 AND ALONG THE HAL ROGERS PARKWAY THIS MORNING AND SO
HAVE UPDATED TO THROW SOME POPS INTO THE MORNING HOURS. MORNING
SOUNDINGS ARE COMING IN A BIT UNSTABLE THIS MORNING AND THESE POPPING
SHOWERS ARE THE RESULT. LOOKS LIKE COVERAGE WILL INCREASE AS THE HEAT
OF THE DAY SETS IN. THIS COUPLED WITH THE NAM AND RUC SHOWING WEAK
UPPER LEVEL SUPPORT CREEPS IN FROM THE WEST. SO ADJUSTED TEMPS AND
CLOUD COVER AND SENT OUT A NEW ZFP.
UPDATE ISSUED AT 741 AM EDT TUE JUL 3 2012
UPDATED SKY COVER GRIDS AND DEW POINTS BASED ON OBSERVED CONDITIONS
EARLY THIS MORNING.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 409 AM EDT TUE JUL 3 2012
A WEAK UPPER TROUGH WILL BE SLOWLY MOVING SOUTHEAST OVER THE REGION
DURING THE PERIOD. IN COMBINATION WITH DIURNAL DESTABILIZATION EACH
DAY...CONVECTION IS EXPECTED TO DEVELOP. WITH FEATURES BEING WEAK...
PRECISELY WHERE IT OCCURS REMAINS TO BE SEEN...AND AT THIS POINT THE
FORECAST WILL DEAL IN GENERALITY. WILL BE USING CHANCE POPS PEAKING
LATE IN THE DAYTIME HOURS. THE NAM HAS INDICATED A CONVECTIVE SYSTEM
MOVING SSW INTO THE AREA LATE WEDNESDAY...AND HAVE USED SLIGHTLY
HIGHER POPS IN OUR NE COUNTIES ON WEDNESDAY. HOWEVER...CONFIDENCE IS
NOT HIGH ENOUGH TO WARRANT A LARGE SPATIAL DIFFERENCE IN POPS.
TEMPS WILL CONTINUE HOT AND NEAR RECORD HIGHS...WITH NO SIGNIFICANT
CHANGE IN AIR MASS.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 400 AM EDT TUE JUL 3 2012
THERE IS GOOD MODEL AGREEMENT WITH THE LONG WAVE PATTERN THROUGH THE
EXTENDED...AS A LARGE RIDGE OF HIGH PRESSURE CENTERED ACROSS THE
CENTRAL CONUS GRADUALLY BUILDS IN ACROSS THE OHIO AND TENNESSEE
VALLEYS...BRINGING REINFORCING HEAT AS WELL AS MAINLY ISOLATED
CONVECTION FROM TIME TO TIME THROUGH THE FIRST PART OF THE
WEEKEND.
BY SUNDAY AND EARLY NEXT WEEK...TROUGHING WILL AMPLIFY ACROSS
THE GREAT LAKES AND NEW ENGLAND. THIS WILL SEND A SURFACE COLD FRONT
SOUTH TOWARDS THE COMMONWEALTH...ALLOWING FOR SOME BETTER CHANCES OF
CONVECTION AS WELL AS COOLER AIR. DETAILS CONTINUE TO BE
CHALLENGING WITH HOW ALL OF THIS UNFOLDS...WITH THE ECMWF SLOWER AND
THE GFS MORE PROGRESSIVE. AS SUCH...HAVE STUCK CLOSE TO A BLEND OF
THE LATEST GUIDANCE AS WELL AS THE INHERITED FORECAST. SATURDAY
LOOKS TO BE THE WARMEST DAY WITH HIGHS IN THE MID TO UPPER 90S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 741 AM EDT TUE JUL 3 2012
VERY LOCALIZED VALLEY FOG WILL DISSIPATE EARLY THIS MORNING...LEAVING
VFR EVERYWHERE. SCATTERED THUNDERSTORMS MAY DEVELOP THIS AFTERNOON
AND BRING LOCALIZED IFR AND GUSTY WINDS. THEY WOULD BE EXPECTED TO BE
ON THE DECLINE DURING THE NIGHT. VERY LOCALIZED VALLEY FOG WILL BE A
POSSIBILITY AGAIN OVERNIGHT...ESPECIALLY WHERE RAIN OCCURS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SHALLENBERGER
SHORT TERM...HAL
LONG TERM....GEOGERIAN
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
902 PM EDT WED JUL 4 2012
.SYNOPSIS...
EXPECT NO MORE THAN ISOLATED THUNDERSTORMS OVERNIGHT WITH FOG IN
AREAS THAT GOT HEAVY RAIN. BROAD HIGH PRESSURE WILL MAINTAIN HOT
AND HUMID CONDITIONS ACROSS THE UPPER OHIO VALLEY INTO SATURDAY.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
HAVE DROPPED SEVERE THUNDERSTORM WATCH EXCEPT FOR 4 PA-WV-MD MOUNTAIN
COUNTIES, WHICH ENDS AT 10 PM. AREAS OF FOG CAN DEVELOP LATE
TONIGHT WHERE HEAVY RAIN HAS OCCURRED.
RECENT RADAR DATA SHOWS NEW THUNDERSTORMS ACROSS NORTHERN OHIO,
MOVING SOUTHEAST TOWARD THE I-80 CORRIDOR. HRRR MODEL OUTPUT SHOWS
THESE DISSIPATING, SO ONLY HAVE ISOLATED MENTIONED FOR A COUPLE
HOURS PAST MIDNIGHT, BUT WILL MONITOR AS SATELLITE DATA SHOWS CB
TOPS COOLING.
FORECASTED TEMPERATURES BASED ON BLEND OF RECENT SURFACE DATA AND
HRRR AND GFS LAMP MODEL OUTPUT.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
RECENT SREF MODEL OUTPUT CONTINUES TO SHOW THE BROAD HIGH PRESSURE
ACROSS THE EASTERN AND CENTRAL U.S. STRENGTHENING THURSDAY AND
FRIDAY, THEN SHRINKING SOUTH SATURDAY.
THE MAIN EFFECT OF THE HIGH PRESSURE WILL BE TO CONTINUE THE HOT
HUMID CONDITIONS, WITH GFS, NAM, AND ECMWF MOS SHOWING THURSDAY
AND FRIDAY HAVING THE HIGHEST AFTERNOON TEMPERATURES. AS THE HIGH
PRESSURE SHRINKS SOUTH SATURDAY, HIGH TEMPERATURES SATURDAY MAY BE
A COUPLE DEGREES LOWER THAN FRIDAY. HOWEVER, HUMID CONDITIONS WILL
PERSIST.
SO HAVE ADDED A HEAT ADVISORY FOR THURSDAY FOR MOST OF THE UPPER
OHIO VALLEY, EXCEPT THE APPALACHIAN MOUNTAINS AND I-80 CORRIDOR.
IN HAZARDOUS WEATHER OUTLOOK HAVE MENTIONED HEAT INDICES WELL INTO
THE 90S FRIDAY AND POSSIBLY SATURDAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
THERE IS GFS/ECMWF ENSEMBLE AGREEMENT TO BEGIN THE PERIOD THAT DEEP
RIDGING WILL BE CENTERED ACROSS THE MISSOURI VALLEY. THE UPPER OHIO
VALLEY WILL BE IN A NORTHWESTERLY FLOW ON THE EASTERN PERIPHERY OF THE
RIDGE. THE MODEL CONSENSUS INDICATES AN AMPLIFYING TREND WITH THE
RIDGE DOMINATING THE WESTERN TWO THIRDS OF THE CONUS AND LOWERING
MID-LEVEL HEIGHTS ACROSS THE UPPER OHIO VALLEY AS A TROUGH BUILDS
INTO THE NORTHEAST.
AFTER A COLD FRONT DROPS SOUTHEAST ACROSS THE AREA AND BRINGS
CHANCE POPS ON SUNDAY, A DRIER AND COOLER FORECAST IS IN PLACE FOR
EARLY NEXT WEEK. HAVE GONE DRY OR WITH SILENT SLIGHT CHC POPS FOR
LOWERING HEIGHTS THROUGH WEDNESDAY. UNCERTAINTY ENTERS THE FORECAST
BY NEXT THURSDAY WITH THE POTENTIAL OF A MID-LEVEL TROUGH PUSHING
FROM THE UPPER MIDWEST SOUTHEASTWARD ACROSS THE AREA. TEMPS ARE
AROUND 5 DEGREES ABOVE NORMAL AHEAD OF THE FRONT ON SUNDAY.
TEMPERATURES WILL THEN LOWER TO NEAR SEASONABLE VALUES FOR MONDAY, TUESDAY
AND WEDNESDAY.
&&
.AVIATION /01Z THURSDAY THROUGH MONDAY/...
EXPECT ONLY RESTRICTIONS TO VFR ACROSS THE UPPER OHIO VALLEY WILL
BE MVFR FOG LATE TONIGHT DUE TO CONTINUED HUMID CONDITIONS. RECENT
RADAR SHOWS ISOLATED THUNDERSTORMS MOVING SOUTHEASTWARD FROM
NORTHERN OHIO, WHICH WILL BE MONITORED TO SEE IF THESE HOLD
TOGETHER TO AFFECT TAF SITES SUCH AS KFKL, KBVI AND KPIT. IFR FOG
CAN OCCUR WHERE HEAVY RAIN OCCURRED, BUT THIS RAIN HAS MISSED
OTHER TAF SITES. EXPECT NONSTOP VFR THURSDAY AFTER 13Z.
OUTLOOK...THURSDAY NIGHT THROUGH MONDAY...
VFR EXPECTED, EXCEPT FOR MORNING MVFR HAZE. RESTRICTIONS WILL ALSO
BE POSSIBLE IN SCATTERED THUNDERSTORMS LATE SATURDAY AND AGAIN ON SUNDAY
AS A FRONT MOVES SOUTHWARD THROUGH THE REGION. VFR CONDITIONS
WILL RETURN ON MONDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...HEAT ADVISORY FROM NOON TO 7 PM EDT THURSDAY FOR OHZ039>041-
048>050-057>059-068-069.
PA...HEAT ADVISORY FROM NOON TO 7 PM EDT THURSDAY FOR PAZ013-014-
020>022-029-031-073-075.
WV...HEAT ADVISORY FROM NOON TO 7 PM EDT THURSDAY FOR WVZ001>004-
012-021>023.
&&
$$
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
704 PM EDT WED JUL 4 2012
.SYNOPSIS...
AN UPPER-LEVEL DISTURBANCE WILL PASS THROUGH THE REGION TONIGHT.
HIGH PRESSURE WILL BUILD OVERHEAD THURSDAY THROUGH FRIDAY...
BRINGING MORE HOT AND HUMID CONDITIONS. A COLD FRONT WILL APPROACH
THE AREA DURING THE WEEKEND INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH THURSDAY/...
TSTMS TAFTN HV RUN INTO WARM MID LVLS...AND HV STRUGGLED TO
MATURE. INSTEAD...AN MCV IN SWRN PA HAS TAKEN OFF. IT/S THE MOST
IMPRESSIVE ITEM ON RGNL RADARS.
20Z HRRR RUN HAS DEVIATED FROM PRVS RUNS. IT TOO IS KEYING ON PA
CNVCTN...BUT THE MDL HAS ITS PLACEMENT INCORRECT-- TOO FAR TO THE
E.
THINK THE CLUSTER IN SWRN PA HAS THE NCSRY PUSH TO OVERCOME CAP.
EXTRAPOLATION WL BRING IT THRU PTMC HIGHLANDS THRU 9PM...NRN SHEN
VLY 9-11 PM...AND INTO DC METRO BY 10 PM. GRIDS HV BEEN ADJUSTED
ACCRDGLY. WL CONT TO MONITOR.
T-STORM CHANCES WILL DECREASE OVERNIGHT DUE TO THE LOSS OF DAYTIME
HEATING. MIN TEMPS WILL RANGE FROM THE 60S IN THE POTOMAC HIGHLANDS
TO THE UPPER 70S AND LOWER 80S IN DOWNTOWN BALTIMORE. HIGH HUMIDITY
WILL MAKE IT FEEL MUGGY OVERNIGHT.
UPPER-LEVEL HIGH PRESSURE WILL BUILD TOWARD THE REGION THURSDAY.
SUBSIDENCE ASSOCIATED WITH THE UPPER-LEVEL HIGH WILL PROVIDE EVEN
HOTTER CONDITIONS WITH MAX TEMPS IN THE UPPER 90S AND LOWER 100S
ACROSS MOST LOCATIONS. THE HEAT AND HUMIDITY WILL CAUSE HEAT INDICES
NEAR OR OVER 105 DEGREES ACROSS MANY AREAS. A HEAT ADVISORY WILL
LIKELY BE NEEDED FOR LOCATIONS EAST OF THE BLUE RIDGE
MOUNTAINS...AND POSSIBLY ACROSS SOME AREAS WEST OF THE BLUE RIDGE.
A SURFACE TROUGH WILL PASS THROUGH THE AREA THURSDAY. THE HOT AND
HUMID CONDITIONS WILL LEAD TO HIGH AMOUNTS OF INSTABILITY.
ISOLATED/SCATTERED T-STORMS ARE POSSIBLE ALONG AND AHEAD OF THIS
TROUGH. THE BEST CHANCE WILL BE ACROSS CENTRAL VIRGINIA INTO LOWER
SOUTHERN MARYLAND. ANY T-STORMS THAT DO DEVELOP CAN BE SEVERE WITH
DAMAGING WIND GUSTS AND LARGE HAIL.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
THE HEAT WILL CONTINUE THRU THE END OF THE WORK WEEK AS THE
MID-ATLANTIC REGION REMAINS SITUATED ON THE NERN SIDE OF AN
EXPANSIVE UPPER RIDGE. OVNGT LOWS THU AND FRI NGT WILL STRUGGLE TO
DROP BELOW 80F IN THE URBAN AREAS. WITH H8 TEMPS INCREASING TO
21-22C AND WEAK DOWNSLOPING FLOW...MAX TEMPS FRI IN THE MID TO UPPER
90S ARE EXPECTED. THE CITIES WILL FLIRT WITH 100F. SUBTLE DRY
ADVECTION BEHIND A SFC TROUGH MAY PRECLUDE ISSUANCE OF A HEAT
ADVISORY FRI. FCST HEAT INDICES NEAR OR JUST ABOVE 100F ARE STILL
CLOSE ENOUGH TO KEEP MENTION OF A HEAT ADVISORY IN HWO.
A TEMPORARY WEAKNESS IN THE RIDGE IS FCST THU NGT AS A MID-LVL
SHORTWAVE TROUGH AND SFC PRESSURE TROUGH MOVES THRU THE
REGION. THIS TROUGH MAY PROVIDE ENOUGH LIFT FOR ISO STORMS DURING
THE EVE AND SHOWERS OVNGT OVER PORTIONS OF THE CWA.
SUBSIDENCE BEHIND THE SHORTWAVE TROUGH AND UNDERNEATH THE UPPER
RIDGE WILL LIKELY CAP CONVECTION FRI. KEPT THE FCST DRY ACCORDINGLY.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
THE DOME OF HOT AIR UNDERNEATH THE UPPER RIDGE WILL SETTLE OVER THE
MID-ATLANTIC REGION SAT. A COLD FRONT WILL APPROACH FROM THE N AND
W...BUT REMAIN UPSTREAM OF THE AREA. OPERATIONAL GUIDANCE IN
AGREEMENT WITH H8 TEMPS OF 24-26C. FOR A REFERENCE...THE H8
TEMPERATURE WAS 24C DURING THE RECORD HEAT ON JUNE 29 /AS SEEN ON
THE 00Z JUNE 30 IAD RAOB/. HAVE INCREASED MAX TEMPS A COUPLE OF
DEGREES FOR SAT /UPPER 90S AND LOW 100S/ WITH THE LATEST FCST...BUT
IT IS STILL ON THE CONSERVATIVE SIDE OF THE WARMEST GUIDANCE. FCST
HEAT INDICES MAY REACH HEAT WRNG CRITERIA OF 110F IN THE URBAN
CORRIDOR AND HEAT ADVISORY CRITERIA ELSEWHERE.
EXTENDED-RANGE MODELS HINTING AT A PATTERN CHANGE LATE THIS WEEKEND
AND ERY NEXT WEEK AS LARGE-SCALE TROUGHING DEVELOPS OVER THE ERN
CONUS. THIS WOULD LEAD TO A BREAK IN THE OPPRESSIVE HEAT...BUT MAY
BE ACCOMPANIED BY A SVR TSTM EVENT EITHER LATE SAT OR SUN WHEN THE
COLD FRONT MOVES THRU.
THE FRONT MAY STALL NEAR CENTRAL VA ERY NEXT WEEK...SO HAVE KEPT LOW
CHANCE POPS ACROSS THE SRN TIER OF THE CWA DURING THIS TIME.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
VFR CONDITIONS EXPECTED MOST OF THE TIME THROUGH TONIGHT.
WEST-SOUTHWEST WINDS THIS AFTERNOON WILL BECOME LIGHT AND VARIABLE
TONIGHT. SCATTERED TO NUMEROUS T-STORMS WL APPROACH FM THE NW
TNGT. T-STORMS WILL BE CAPABLE OF PRODUCING GUSTY WINDS AND HAIL.
INHERENT UNCERTAINTIES WL KEEP METION DOWN TO VCTS FOR MOST
AFFECTED TIME FRAME.
VFR CONDITIONS ARE EXPECTED THURSDAY WITH NORTHWEST WINDS. WIND
GUSTS AROUND 15 KNOTS ARE EXPECTED. ISO STORMS POSSIBLE THU AFTN
AND EVE...ESPECIALLY IN VC OF CHO. A FEW STORMS MAY PRODUCE GUSTY
WINDS AND HAIL.
GENERALLY VFR CONDITIONS THRU THE WEEKEND. CHANCE OF STORMS SAT NGT
AND SUN AS A COLD FRONT APPROACHES FROM THE NW.
&&
.MARINE...
WEST-SOUTHWEST WINDS THIS AFTERNOON AND TONIGHT WILL GUST AROUND 15
KNOTS. SCATTERED T-STORMS ARE EXPECTED LATE THIS AFTERNOON INTO
TONIGHT. T-STORMS WILL BE CAPABLE OF PRODUCING GUSTY WINDS AND HAIL.
NORTHWEST WINDS WILL GUST AROUND 15 KNOTS THURSDAY. ISOLATED
T-STORMS ARE POSSIBLE...ESPECIALLY ACROSS THE SOUTHERN PORTION OF
THE WATERS. ANY T-STORMS THAT DO DEVELOP WILL BE CAPABLE OF
PRODUCING GUSTY WINDS AND HAIL.
LGT WINDS THRU THE WEEKEND. STORMS MAY IMPACT THE WATERS SAT NGT AND
SUN.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...HEAT ADVISORY UNTIL 9 PM EDT THIS EVENING FOR DCZ001.
MD...HEAT ADVISORY UNTIL 9 PM EDT THIS EVENING FOR MDZ006-007-
009>011-013-014-016>018.
VA...HEAT ADVISORY UNTIL 9 PM EDT THIS EVENING FOR VAZ037-042-
050>057-502.
WV...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...HTS/LASORSA
SHORT TERM...KLEIN
LONG TERM...KLEIN
AVIATION...HTS/LASORSA/KLEIN
MARINE...LASORSA/KLEIN
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
246 PM EDT TUE JUL 3 2012
.SYNOPSIS...
BROAD UPPER HIGH PRESSURE WILL MAINTAIN VERY WARM AND HUMID WEATHER
ACROSS THE UPPER OHIO VALLEY INTO THE WEEKEND. A SLOW MOVING UPPER
LEVEL LOW PRESSURE TROUGH MAY CAUSE SCATTERED THUNDERSTORMS WITH
GUSTY WINDS AND HAIL INTO EARLY EVENING. THE CHANCE OF THUNDERSTORMS
WILL CONTINUE TONIGHT INTO THE DAYTIME HOURS OF THE FOURTH.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
WILL CONTINUE MENTION OF NUMEROUS SHOWERS AND THUNDERSTORMS ACROSS
THE UPPER OHIO VALLEY INTO EARLY EVENING, WITH POSSIBLE GUSTY WIND
AND HAIL. THIS IDEA BASED ON RECENT RADAR DATA AND SURFACE REPORTS,
COUPLED WITH HRRR SIMULATED RADAR PREDICTIONS.
WILL CONTINUE MENTION OF A CHANCE OF THUNDERSTORMS INTO THE DAYTIME
HOURS OF WEDNESDAY JULY 4TH INDEPENDENCE DAY, BASED ON BLEND OF SREF
AND SPECIFIC WRF-NMM MODEL OUTPUT THAT SHOWS A SECOND
THUNDERSTORM BAND MAY MOVE SOUTHWARD THROUGH THE UPPER OHIO VALLEY
TOWARD MIDNIGHT AND A POSSIBLE THIRD BAND OF SCATTERED THUNDERSTORMS
DAYTIME WEDNESDAY.
MADE MINOR ADJUSTMENTS TO TEMPERATURES BASED ON PREFERRED WARMER NAM
MOS. THIS NECESSITATED THE CONTINUATION OF THE IMPACTS-BASED HEAT
ADVISORY FOR INDEPENDENCE DAY FOR COUNTIES IN EASTERN OHIO AND
NORTHERN WEST VIRGINIA WHERE WIDESPREAD POWER OUTAGES REMAIN. THIS
IS FOR CRITERIA BETWEEN 90 AND 95 DEGREES. THE HEAT INDEX FOR SOME
OHIO COUNTIES CAN PEAK AT 102, WHICH EXCEEDS THE TYPICAL 100-DEGREE
CRITERIA.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
SREF MODEL OUTPUT SHOWS INCREASED RIDGING THURSDAY INTO FRIDAY. THIS
WILL SUPPRESS THUNDERSTORM DEVELOPMENT, BUT ENHANCE DAYTIME HEATING.
FORECASTED SPECIFIC TEMPERATURES HEDGING TOWARD WARMER NAM MOS
THURSDAY, AND WARMER ECMWF MOS FRIDAY, WHICH MEANS MOST LOWER
ELEVATIONS CAN HAVE HIGHS IN THE MID 90S THURSDAY AND POSSIBLY THE
UPPER 90S FRIDAY. LOWS WILL BE IN THE 65 TO 70 RANGE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
UPPER RIDGE IS PROJECTED TO PERSIST OVER THE MS VALLEY AND MAINTAIN
WARM TEMPERATURES OVER THE WEEKEND. FORECAST READINGS ARE CLOSE TO
HPC NUMBERS WITH DAYTIME HIGHS AROUND 10 DEGREES ABOVE NORMAL FOR
SATURDAY AND SUNDAY. MODELS SHOW THE RIDGE FLATTENING AND SHIFTING
WESTWARD EARLY NEXT WEEK WHICH SHOULD SUPPORT A DOWNWARD TEMPERATURE
TREND...WITH READINGS CLOSER TO NORMAL BY TUESDAY.
A WEAK FRONT IS PROGGED TO SAG SOUTHWARD ACROSS ACROSS THE FORECAST
AREA LATE SATURDAY AND SUNDAY...BRINGING THE RISK FOR SHOWERS AND
STORMS. THE BOUNDARY IS PROGGED TO BECOME NEARLY STATIONARY JUST TO
THE SOUTH OF THE FORECAST AREA EARLY NEXT WEEK.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
AN AREA OF SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS EAST CENTRAL
OHIO AND WESTERN PA THROUGH EARLY EVENING. INCLUDED TEMPO GROUPS
FOR MVFR RESTRICTIONS AT MOST TAF LOCATIONS...BUT ISOLATED IFR
CONDITIONS ARE POSSIBLE THROUGH 23Z. IN ADDITION...AREAS OF MVFR FOG
AND HAZE CAN BE EXPECTED EARLY WEDNESDAY MORNING.
VFR CONDITIONS WILL PREVAIL WEDNESDAY AFTERNOON...WITH A CHANCE OF
BRIEF RESTRICTIONS FROM SCATTERED THUNDERSTORMS.
OUTLOOK...WEDNESDAY NIGHT THROUGH SUNDAY...
GENERALLY VFR CONDITIONS ARE EXPECTED. RESTRICTIONS ARE POSSIBLE IN
SCATTERED STORMS LATE SATURDAY AND SUNDAY AS A FRONT SAGS SOUTHWARD
THROUGH THE REGION.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR OHZ039-048-
057>059-068-069.
HEAT ADVISORY FROM 11 AM TO 7 PM EDT WEDNESDAY FOR OHZ039-048-
057>059-068-069.
PA...NONE.
WV...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR WVZ004-012-
021>023.
HEAT ADVISORY FROM 11 AM TO 7 PM EDT WEDNESDAY FOR WVZ004-012-
021>023.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
103 PM EDT TUE JUL 3 2012
.SYNOPSIS...
BROAD UPPER HIGH PRESSURE WILL MAINTAIN VERY WARM AND HUMID
WEATHER OVER THE UPPER OHIO VALLEY INTO THE WEEKEND. A SLOW
MOVING UPPER LEVEL LOW PRESSURE TROUGH MAY CAUSE SCATTERED
THUNDERSTORMS WITH GUSTY WINDS AND HAIL INTO EARLY EVENING. THE
CHANCE OF THUNDERSTORMS WILL CONTINUE TONIGHT INTO THE DAYTIME
HOURS OF THE FOURTH.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HAVE UPWARD ADJUSTED COVERAGE OF THUNDERSTORMS THROUGH EARLY
EVENING AND ADDED MENTION OF GUSTY WINDS AND HAIL, PER BLEND OF
RECENT RADAR AND SURFACE DATA, HRRR MODEL OUTPUT AND SPC
GUIDANCE/CONVECTIVE OUTLOOK SHOWING SLIGHT RISK OF SEVERE
THUNDERSTORMS NORTH OF I-70/.
MADE A SMALL ADJUSTMENT TO TEMPERATURES BASED ON THE PROSPECT OF
THUNDERSTORM DEVELOPMENT, BUT STILL EXPECT HIGHS UP TO 10 DEGREES
ABOVE NORMAL, AS INDICATED BY PREFERRED WARMER NAM MOS.
THE IMPACTS-BASED HEAT ADVISORY HAS BEEN CONTINUED FOR COUNTIES
IN EASTERN OHIO AND NORTHERN WEST VIRGINIA WHERE WIDESPREAD POWER
OUTAGES REMAIN. THIS IS FOR CRITERIA BETWEEN 90 AND 95 DEGREES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
SHORTWAVE IS PROJECTED TOWARD NEW ENGLAND BY WEDNESDAY WITH THE
UPPER LEVEL TROUGH AXIS EXTENDING BACK ACROSS THE UPPER OHIO
VALLEY ALONG WITH THE WIND SHIFT. HAVE THUS CONTINUED CHANCE POPS
INTO WEDNESDAY...BUT ALLOWED FOR A GRADUAL DECLINE TOWARD EVENING
GIVEN CONSISTENT TIMING...WITH CESSATION OF PCPN BY LATE WEDNESDAY
EVENING. EXPECT DRY WEATHER UNDER BUILDING HIGH PRESSURE FOR LATE
WEDNESDAY NIGHT AND THURSDAY.
TEMPERATURES WILL REMAIN WELL ABOVE NORMAL THROUGH THE SHORT TERM PERIOD.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
UPPER RIDGE IS PROJECTED TO PERSIST OVER THE MS VALLEY AND MAINTAIN
WARM TEMPERATURES INTO THE WEEKEND. FORECAST READINGS ARE CLOSE
TO HPC NUMBERS WITH DAYTIME HIGHS BETWEEN 10 AND 15 DEGREES ABOVE
THE NORM. MODELS SHOW RIDGE FLATTENING AND SHIFTING WESTWARD DURING
THE WEEKEND WHICH SHOULD SUPPORT A DOWNWARD TREND OF A FEW
DEGREES.
A WEAK FRONT IS PROGGED TO SAG SOUTHWARD ACROSS THE GREAT LAKES AND
ACROSS THE FORECAST AREA LATE SATURDAY AND SUNDAY...BRINGING THE
RISK FOR SHOWERS AND STORMS.
&&
.AVIATION /17Z TUESDAY THROUGH SATURDAY/...
HAVE ADDED MENTION OF A SHORT PERIOD OF MVFR THUNDERSTORMS WITH
GUSTS TO 30 KTS FOR TAF SITES SUCH AS KFKL, KPIT, KBVI, KAGC, AND
KHLG THROUGH 20Z. THIS WAS BASED ON TRENDS IN RECENT RADAR DATA
AND HRRR MODEL OUTPUT. CONFIDENCE TOO LOW TO MENTION ELSEWHERE,
BUT MAY BE ADJUSTED BASED ON THUNDERSTORM COMPLEX MOVEMENT INTO
WESTERN PENNSYLVANIA.
OTHERWISE VFR WILL BE PREVALENT THROUGH WEDNESDAY, WITH A CHANCE
OF BRIEF RESTRICTIONS FROM SCATTERED THUNDERSTORMS.
OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY...
VFR, EXCEPT RESTRICTIONS POSSIBLE IN EARLY MORNING FOG THURSDAY,
AND ISOLATED STORMS LATE SATURDAY AHEAD OF AN APPROACHING FRONT.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR OHZ039-048-
057>059-068-069.
PA...NONE.
WV...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR WVZ004-012-
021>023.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1114 AM EDT TUE JUL 3 2012
.SYNOPSIS...
BROAD UPPER HIGH PRESSURE WILL MAINTAIN VERY WARM AND HUMID
WEATHER OVER THE UPPER OHIO VALLEY INTO THE WEEKEND. A SLOW
MOVING UPPER LEVEL LOW PRESSURE TROUGH MAY CAUSE SCATTERED
THUNDERSTORMS WITH GUSTY WINDS THIS AFTERNOON. THE CHANCE OF
THUNDERSTORMS WILL CONTINUE TONIGHT INTO THE DAYTIME HOURS OF THE
FOURTH.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HAVE ADJUSTED COVERAGE OF THUNDERSTORMS THROUGH EARLY EVENING AND
ADDED MENTION OF GUSTY WINDS, PER BLEND OF RECENT RADAR AND
SURFACE DATA, HRRR MODEL OUTPUT AND SPC GUIDANCE/MESOSCALE
DISCUSSION 1373/.
MADE A SMALL ADJUSTMENT TO TEMPERATURES BASED ON THE PROSPECT OF
THUNDERSTORM DEVELOPMENT, BUT STILL EXPECT HIGHS UP TO 10 DEGREES
ABOVE NORMAL, AS INDICATED BY PREFERRED WARMER NAM MOS.
THE IMPACTS-BASED HEAT ADVISORY HAS BEEN CONTINUED FOR COUNTIES
IN EASTERN OHIO AND NORTHERN WEST VIRGINIA WHERE WIDESPREAD POWER
OUTAGES REMAIN. THIS IS FOR CRITERIA BETWEEN 90 AND 95 DEGREES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
SHORTWAVE IS PROJECTED TOWARD NEW ENGLAND BY TONIGHT/INTO WEDNESDAY
WITH THE UPPER LEVEL TROUGH AXIS EXTENDING BACK ACROSS THE UPPER OHIO
VALLEY ALONG WITH THE WIND SHIFT. HAVE THUS CONTINUED CHANCE POPS INTO
WEDNESDAY...BUT ALLOWED FOR A GRADUAL DECLINE TOWARD EVENING GIVEN CONSISTENT
TIMING...WITH CESSATION OF PCPN BY LATE WEDNESDAY EVENING. EXPECT DRY
WEATHER UNDER BUILDING HIGH PRESSURE FOR LATE WEDNESDAY NIGHT AND THURSDAY.
TEMPERATURES WILL REMAIN WELL ABOVE NORMAL THROUGH THE SHORT TERM PERIOD.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
UPPER RIDGE IS PROJECTED TO PERSIST OVER THE MS VALLEY AND MAINTAIN
WARM TEMPERATURES INTO THE WEEKEND. FORECAST READINGS ARE CLOSE
TO HPC NUMBERS WITH DAYTIME HIGHS BETWEEN 10 AND 15 DEGREES ABOVE
THE NORM. MODELS SHOW RIDGE FLATTENING AND SHIFTING WESTWARD DURING
THE WEEKEND WHICH SHOULD SUPPORT A DOWNWARD TREND OF A FEW
DEGREES.
A WEAK FRONT IS PROGGED TO SAG SOUTHWARD ACROSS THE GREAT LAKES AND
ACROSS THE FORECAST AREA LATE SATURDAY AND SUNDAY...BRINGING THE
RISK FOR SHOWERS AND STORMS.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
HAVE ADDED MENTION OF A SHORT PERIOD OF MVFR THUNDERSTORMS WITH
GUSTS TO 30 KTS FOR TAF SITES SUCH AS KFKL, KPIT, KBVI, KAGC, AND
KHLG THROUGH 20Z. THIS WAS BASED ON TRENDS IN RECENT RADAR DATA
AND HRRR MODEL OUTPUT. CONFIDENCE TOO LOW TO MENTION ELSEWHERE,
BUT MAY BE ADJUSTED BASED ON THUNDERSTORM COMPLEX MOVEMENT INTO
WESTERN PENNSYLVANIA.
OTHERWISE VFR WILL BE PREVALENT THROUGH WEDNESDAY, WITH A CHANCE
OF BRIEF RESTRICTIONS FROM SCATTERED THUNDERSTORMS.
OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY...
VFR, EXCEPT RESTRICTIONS POSSIBLE IN EARLY MORNING FOG THURSDAY,
AND ISOLATED STORMS LATE SATURDAY AHEAD OF AN APPROACHING FRONT.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR OHZ039-048-
057>059-068-069.
PA...NONE.
WV...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR WVZ004-012-
021>023.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
431 PM EDT TUE JUL 3 2012
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 430 PM EDT TUE JUL 3 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A BROAD MID/UPPER LEVEL RIDGE
FROM THE SRN ROCKIES AND CNTRL PLAINS INTO THE UPPER MS VALLEY
RESULTING IN WNW FLOW THROUGH THE NRN GREAT LAKES. A WEAK SHRTWV
MOVING THROUGH NE ND HAS TRIGGERED ANY SHRA/TSRA. AT THE SFC...LOW
PRES WAS LOCATED WEST OF JAMES BAY WITH A WEAK COLD FRONT TRAILING
SW INTO NE MN AND NE SD. THE GRADIENT REMAINED WEAK ENOUGH SO THAT
LAKE BREEZES HAVE DEVELOPED OFF OF BOTH LAKE SUPERIOR AND LAKE MI.
DESPITE T/TD CLIMBING TO NEAR 93/64 INLAND WITH MLCAPE VALUES IN THE
2K-3K J/KG RANGE...CAPPING HAS BEEN STRONG ENOUGH TO SUPPRESS
CONVECTION SO FAR WITH ONLY RELATIVELY SHALLOW CU OVER THE WEST AND
ALONG LAKE BREEZES OVER THE EAST.
TONIGHT...CANNOT RULE OUT SOME ISOLD SHRA AND POSSIBLY A TSTM OVER
THE SOUTH AND EAST THIS EVENING GIVEN THE AMOUNT OF INSTABILITY
AVBL. HOWEVER...ONLY SLIGHT CHANCE WAS MENTIONED GIVEN CURRENT
TRENDS. WITH THE LOSS OF DAYTIME HEATING...ANY REMAINING PCPN
CHANCES WILL DIMINISH/END BY LATE EVENING. EXPECT MIN TEMPS WELL
ABOVE NORMAL WITH LOWS ONLY IN THE MID TO UPPER 60S.
WED...AS A SHORTWAVE AND SFC LOW MOVE INTO CNTRL SASK...INCREASING
SRLY FLOW INTO THE UPPER MS VALLEY WILL PUSH A WARM FRONT BACK
TOWARD THE REGION. MLCAPE VALUE SHOULD AGAIN CLIMB TO NEAR 3K J/KG
NEAR THE FRONT. HOWEVER...SIMILAR TODAY...NO SIGNIFICANT SHRTWVS ARE
FCST INTO THE AREA AND CAPPING SHOULD BE STRONG ENOUGH TO LIMIT TSRA
CHANCES. SLIGHT CHANCES WERE AGAIN INCLUDED OVER THE WEST CLOSEST TO
THE WARM FRONT AND 925-850 MB THETA-E GRADIENT.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 430 PM EDT TUE JUL 3 2012
ONE OF THE HOTTEST DAYS OF THE YEAR WILL BE THURSDAY...AS THE 500MB
RIDGE SETS UP ACROSS MUCH OF THE CENTRAL U.S. THE 500MB LOW OVER N
SASKATCHEWAN AND MANITOBA AT 00Z THURSDAY WILL CROSS INTO HUDSON BAY
AND N ONTARIO BY 06Z FRIDAY.
DID ADJUST TEMPS DOWN A COUPLE OF DEGREES FOR THE FAR W THROUGH THE
BARAGA PLAINS...GIVEN THE QUICKER COLD FRONT WHICH LOOKS TO BE SET
UP ACROSS THE KEWEENAW PENINSULA THROUGH IWD AND NW WI AT 12Z
TUESDAY. EXPECT THE COLD FRONT TO PUSH E...AND SET UP JUST E OF THE
CWA BY 00Z FRIDAY. DUE TO A FASTER SOLUTION DAY 2/3...THE HIGH
CHANCE POPS FOR THURSDAY NIGHT AND FRIDAY WERE PUSHED BACK TO SLIGHT
CHANCE OR DRY CONDITIONS. THERE IS MODERATE TO LOW CONFIDENCE IN
THIS SOLUTION.
WITH HIGH PRESSURE ROLLING IN FROM CENTRAL CANADA AND THE NORTHERN
PLAINS...EXPECT A SLIGHT COOL DOWN...BUT ALSO DRIER AIR TO MIX DOWN
DURING THE AFTERNOON HOURS. LOWERED DEWPOINTS THURSDAY NIGHT THROUGH
SATURDAY. AT THIS POINT THAT WOULD BRING ABOUT MIN RH VALUES INTO
THE 35 TO 45 PERCENT RANGE FOR BOTH FRIDAY AND SATURDAY. WOULD NOT
BE SURPRISED IF THEY FALL CLOSER TO OR BELOW 30 PERCENT FOR MOST
LOCATIONS...ESPECIALLY IF THE LIMITED SHOWERS STILL IN THERE FOR
FRIDAY NIGHT /THANKS TO THE WETTER ECMWF/ DO NOT PAN OUT.
OTHERWISE...TEMPS IN THE MID TO UPPER 70S LOOK TO BE THE RULE FROM
SATURDAY THROUGH NEXT TUESDAY. THE SFC HIGH SHOULD BE OVERHEAD BY
06Z SUNDAY...BEING REINFORCED BY ANOTHER HIGH PRESSURE SYSTEM
BUILDING INTO THE NORTHERN AND CENTRAL PLAINS FOR EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 134 PM EDT TUE JUL 3 2012
ISOLD SHRA/TSRA MAY REDEVELOP INLAND ALONG LAKE BREEZE BOUNDARIES THIS
AFTERNOON...BUT NOT ENOUGH CONFIDENCE TO INCLUDE A MENTION AT KSAW
IN TAF. WITH LINGERING MOIST CONDITIONS...LOOK FOR PATCHY FOG TO
REDEVELOP AT KCMX LATER THIS EVENING AND OVERNIGHT POSSIBLY LOWER
VBSYS/CIGS TO IFR. PATCHY FOG WILL LIKELY LOWER VSBYS TO MVFR AT
BOTH KIWD AND KSAW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 430 PM EDT TUE JUL 3 2012
WINDS ARE EXPECTED TO REMAIN BELOW 20KTS THROUGH SATURDAY WITH A
HIGH PRESSURE RIDGE REMAINING THE DOMINANT FEATURE THROUGH MUCH OF
THE PERIOD. AREAS OF FOG...ESPECIALLY EAST...ARE EXPECTED FROM LATE
TONIGHT THROUGH EARLY FRIDAY WITH ABUNDANT LOW LEVEL MOISTURE OVER
THE REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KF
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
205 AM EDT TUE JUL 3 2012
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 414 PM EDT MON JUL 2 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A RIDGE FROM THE SRN ROCKIES
AND PLAINS INTO THE UPPER MS VALLEY. A WEAK SHORTWAVE TROUGH
CRESTING THE RIDGE INTO SE MANITOBA AND THE ADJACENT PORTION OF NRN
ONTARIO HAS HELPED TO TRIGGER TSRA OVER THE NW CORNER OF MN. AT THE
SFC...A WARM FRONT EXTENDED THROUGH NRN MN INTO CNTRL WI FROM LOW
PRES OVER SE NORTH DAKOTA. HOT AND HUMID AIR NEAR AND SOUTH OF THE
FRONT HAS PUSHED MLCAPE VALUES INTO THE 3K-4K J/KG RANGE. ISOLD
SHRA/TSRA HAVE DEVELOPED OVER NRN WI AND FAR SRN UPPER MI BUT HAVE
ALSO DISSIPATED QUICKLY WHERE LITTLE LARGE SCALE FORCING AND
RELATIVELY WARM MID LEVEL TEMPS WERE NOT FAVORABLE FOR MORE
WIDEPSREAD COVERAGE.
TONIGHT...
MODELS WERE IN RELATIVE AGREEMENT THAT CONVECTION WILL EXPAND OVER
NRN MN THIS EVENING. HOWEVER...A RANGE OF SOLUTIONS REMAIN ON THE
EVOLUTION OF THE CONVECTION AND LOCATION/TRACK OF THE EXPECTED MCS
MOVING OUT OF NRN MN. WITH ANL ESE TRACK TO ANY MCS AND A
POSSIBLE FURTHER TURN TO THE SOUTH...PER FOREWARD PROPAGATION
CORFIDI VECTORS AND 850-300 EXPECT THAT THE MAJORITY OF THE CWA WILL
SEE AT LEAST SOME PRECIPITATION...ESPECIALLY BTWN 03Z-12Z. THERE IS
GREATER UNCERTAINTY WHERE THE STRONGEST CONVECTION AND HEAVIER RAIN
WILL OCCUR WITH GREATEST CHANCE CLOSER TO THE WI BORDER. THE OVERALL
PATTERN REMAINS FAVORABLE FOR FOR SVR TSTMS WITH DAMAGING...PER
SPC...GIVEN VERY UNSTABLE AIR ALONG AND SOUTH OF THE WARM FRONT
(MUCAPE VALUES REMAINING IN THE 2K-3K J/KG RANGE).
TUESDAY...REMAING SHRA/TSRA ASSOCIATED WITH THE SHORTWAVE TROUGH AND
WARM FRONT IS EXPECTED TO MOVE OUT OF THE AREA IN THE
MORNING...LEAVING PLENTY OF SUNSHINE BY MID AFTERNOON. THIS SHOULD
ALLOW TEMPS TO CLIMB AGAIN INTO THE UPPER 80S TO AROUND 90 INLAND
WITH COOLER AIR ONLY ALONG THE GREAT LAKES SHORELINES.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 414 PM EDT MON JUL 2 2012
WE WILL BEGIN THE PERIOD WITH RIDGE ENHANCING 500MB LOWS OVER NE
HUDSON BAY/QUEBEC...AND SW CANADA. A TROUGH EXTENDING S FROM THE E
CANADA LOW WILL BE JUST TO OUR E BY 00Z WEDNESDAY. ANY LINGERING
PRECIP SHOULD BE QUICKLY EXITING E AS THE SFC SHIFTS FROM S JAMES
BAY AND E LAKE SUPERIOR AT 00Z WEDNESDAY WITH THE WEAK COLD FRONT
SINKING SE TO N LOWER MI AND LAKE HURON BY OR SHORTLY AFTER 06Z
WEDNESDAY.
LOOK FOR THE HEAT TO RETURN WEDNESDAY AS THE WEAK COLD FRONT RESTS
OVER S LOWER MI AND WI TO THE NEXT LOW DEVELOPING ACROSS SD. 850MB
TEMPS WILL NOT BUDGE MUCH DURING THIS THEORETICAL COOL DONN
PERIOD...FROM 20C AT 00Z WEDNESDAY UP TO AN AVERAGE 21C BY 00Z
THURSDAY AS HIGH PRESSURE RESIDES AT THE SFC. DEW POINTS SHOULD
CHANGE THOUGH...AND HAVE LOWERED THEM SLIGHTLY AS A RESULT. LATER
SHIFTS MAY WANT TO LOOK AT FURTHER LOWERING FOR WEDNESDAY AS THE
TIME NEARS.
EXPECT THE SFC HIGH TO EDGE E WEDNESDAY NIGHT AS STRONGER LOW
PRESSURE PUSHES ACROSS N MANITOBA...WITH A WEAK TROUGH/COLD FRONT
SWINGING OVER FAR W LAKE SUPERIOR BY 12Z THURSDAY...AND THE WARM
FRONT SET UP ACROSS THE REGION. EVEN WITH THESE FRONTAL
PASSAGES...THEY REMAIN WEAK...WITH LIGHT WINDS AT THE SFC THROUGH
850MB...WITH LAKE BREEZES CONTINUING TO BE POSSIBLE. THE WARMEST
CONDITIONS FOR THE WEEK WILL LIKELY BE THURSDAY...INLAND FROM AREAS
RIGHT NEAR THE GREAT LAKES. 850MB TEMPS PUSH TO AROUND 22C BY
MID/LATE AFTERNOON. THE GFS IS A BIT STRONGER WITH THE S FLOW...AND
WOULD LIMIT AFTERNOON LAKE BREEZES /COOL DOWN/ OVER N CENTRAL UPPER
MI. HEAT INDEX VALUES/APPARENT TEMPS WILL LIKELY JUMP INTO THE 92 TO
99 DEGREE RANGE...HIGHEST WEST AND CENTRAL.
THE WEAK COLD FRONT SHOULD WASH OUT ACROSS UPPER MI THURSDAY AS
ANOTHER LOW BECOMES BETTER ORGANIZED ACROSS THE CENTRAL PLAINS.
THERE ARE SOME INDICATIONS THAT THE FRONT WILL SINK TO OUR SE BY
DAYBREAK FRIDAY...AND CONTINUE TO SLIP S DURING THE DAY AS STRONGER
HIGH PRESSURE BUILDS ACROSS THE UPPER GREAT LAKES FROM S CENTRAL
CANADA THROUGH AT LEAST SUNDAY NIGHT /DIRECTLY OVERHEAD FROM 00Z
SUNDAY THROUGH 00Z MONDAY/. TEMPS STILL LOOK TO COOL OFF A BIT FROM
SATURDAY THROUGH MONDAY...TOPPING OUT IN THE 70S FOR MOST LOCATIONS.
A CONSENSUS OF MODEL DATA LOOKED TO BE A GOOD SOLUTION FOR MUCH OF
THIS LONG TERM PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 205 AM EDT TUE JUL 3 2012
THUNDERSTORM COMPLEX MOVING ACROSS UPPER MI HAS PRODUCED HEAVY RAIN
AND STRONG WINDS ACROSS MUCH OF THE WEST HALF OF UPPER MI LATE THIS
EVENING INTO THE EARLY OVERNIGHT. THE RAIN COMBINED WITH A
DEVELOPING ONSHORE FLOW WILL PRODUCE IFR CONDITIONS AT KCMX THRU
MUCH OF THE OVERNIGHT. A LINE OF THUNDERSTORMS WILL ALSO PRODUCE
GUSTY WRLY WINDS TO 30 MPH AT KSAW THROUGH 08Z. ANY LINGERING SHRA
SHOULD DISSIPATE BY 10Z...EXPECT VFR CONDITIONS AT KSAW AND KIWD
THEREAFTER. IFR CONDITIONS IN FOG AT KCMX SHOULD LIFT AROUND
SUNRISE. THERE COULD BE SOME MORE SCT SHRA/TSRA REDEVELOPING ALONG
CONVERGING LAKE BREEZE BOUNDARIES THIS AFTERNOON...BUT NOT ENOUGH
CONFIDENCE TO INCLUDE A MENTION AT KSAW IN TAF. WITH LINGERING MOIST
CONDITIONS...LOOK FOR PATCHY FOG TO REDEVELOP AT KCMX LATER THIS
EVENING AND POSSIBLY LOWER VBSYS/CIGS TO IFR.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 414 PM EDT MON JUL 2 2012
WINDS ARE GENERALLY EXPECTED TO REMAIN BELOW 20KTS THROUGH SATURDAY.
THERE WILL BE A CONDITIONAL TRHEAT FOR A BRIEF PERIOD OF HIGHER
WINDS WITH AN MCS THAT COULD MOVE THROUGH LAKE SUPERIOR OVERNIGHT
INTO TUE MORNING. AREA OF FOG ARE EXPECTED FROM TUESDAY THROUGH
EARLY FRIDAY WITH ABUNDANT LOW LEVEL MOISTURE OVER THE REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KF
AVIATION...VOSS
MARINE...JLB
AREA FORECAST DISCUSSION
NWS GAYLORD MI
150 AM EDT TUE JUL 3 2012
.SYNOPSIS...
ISSUED AT 358 PM EDT MON JUL 2 2012
WARM AND HUMID WEATHER WILL CONTINUE TO HOLD ON ACROSS THE REGION
THROUGHOUT THE PERIOD...AS HIGH PRESSURE BUILDS INTO THE GREAT
LAKES. AN UPPER LEVEL DISTURBANCE WILL BRING A CHANCE FOR SHOWERS
AND THUNDERSTORMS TUESDAY...BUT THE WEATHER WILL BE RELATIVELY QUIET
OTHERWISE FOR THE FOURTH OF JULY HOLIDAY WEEK. THE COMING WEEKEND
WILL FEATURE SLIGHTLY COOLER TEMPERATURES...WITH ADDITIONAL SMALL
CHANCES FOR SHOWERS AND STORMS.
&&
.UPDATE...
ISSUED AT 143 AM EDT TUE JUL 3 2012
ONLY HIGH BASED ISOLATED SHOWERS WERE COMMON OVER THE LAST FEW
HOURS...ALTHOUGH LATEST RADAR SHOWING A DECENT STORM WORKING
TOWARD BENZIE COUNTY...WHICH THEORETICALLY SHOULD GRADUALLY WANE
AS THIS STORM MOVES FURTHER AWAY FROM THE BETTER MOISTURE AND
INSTABILITY. MEANWHILE...THE MAIN FEATURE HAS BEEN UPSTREAM WITH
BOW ECHO...CURRENTLY ACROSS CENTRAL UPPER AND NE WISCONSIN. THIS
FEATURE HAD BEEN TRUCKING ALONG JUST FINE...PACKING WIND GUSTS
EASILY INTO THE 35-45MPH RANGE. HOWEVER...CONVECTION OUT AHEAD OF
THIS FEATURE HAS STABILIZED THE BL TO SOME DEGREE...AND THE STORM
SEEMS TO BE WEAKENING...WHILE ALSO DIVING SOUTHEAST...ALONG THE
MAIN LOW LEVEL WARM FRONT. THIS A BIT SURPRISING CONSIDERING THE
NICE SHORTWAVE ALOFT HELPING TO DRIVE IT. STILL BELIEVE THAT THE
EASTERN UP WILL BE IN FOR SOME RAIN AND THUNDER TONIGHT...BUT THE
MAIN SEVERE WEATHER THREAT MAY IN FACT BE OUT TO OUR WEST...WHILE
WE JUST GET SOME EMBEDDED THUNDERSTORMS TO ROLL THROUGH MAINLY THE
WESTERN AND NORTHERN CWA.
UPDATE ISSUED AT 1034 PM EDT MON JUL 2 2012
UPSTREAM RADAR RETURNS HAVE SLIGHTLY INCREASED ACROSS WRN UPR
MICHIGAN AND NE WISCONSIN OVER THE PAST FEW HOURS...ALIGNED ALONG
THE 850 MB THETA E AND INSTABILITY GRADIENTS. EVEN FURTHER
UPSTREAM...IMPRESSIVE MCS/BOW ECHO CONTINUES TO IMPACT NRN
MINNESOTA...WITH ADDITIONAL CONVECTION DEVELOPING OVER FAR WRN
LAKE SUPERIOR WITHIN AN AREA OF MAX CAPE (AROUND 5000 J/KG).
CLOSER TO HOME...ANY ATTEMPS TO GENERATE EVEN THE WEAKEST
CONVECTION OVER OUR CWA HAVE FAILED THANKS TO A DECENT CAP
OVERHEAD PER 00Z APX SOUNDING. ALSO...SURFACE DWPTS WERE MAINLY IN
THE 50S MUCH OF THE DAY AND EARLY EVENING...BUT HAVE NOW SURGED
INTO THE LOW TO MID 60S AS LOW LEVEL MOISTURE BEGINS TO INCREASE
IN ADVANCE OF THE UPSTREAM CONVECTION AND COOL FRONT. LAST SEVERAL
RUNS OF THE HRRR HAVE SUGGESTED HIGHEST POPS/QPF WILL FOCUS
FURTHER NORTHWARD ACROSS ERN UPR MICHIGAN AND THE TIP OF THE MIT
AS REMNANTS OF THE UPSTREAM MCS REACH OUR CWA VERY LATE TONIGHT.
ALSO...EXPECT SOME SEMBLANCE OF THE SCATTERED CONVECTION
DEVELOPING AHEAD OF THE MCS WILL IMPACT MAINLY WRN SECTIONS OF OUR
CWA BEFORE THE MAIN MCS ARRIVES. HAVE MODIFIED WX/POPS FOR THE
BALANCE OF THE NIGHT TO ACCOUNT FOR ALL OF THE ABOVE. ANY
POTENTIAL FOR AN ISOLD STRONG/SVR WIND GUST/HAIL WILL HOLD OFF
UNTIL AROUND OR AFTER SUNRISE AS WIND FIELDS BEGIN TO STRENGTHEN
AND VERTICAL SHEAR BEGINS TO DEVELOP. HOWEVER...THE POTENTIAL FOR
THIS WILL BE GREATLY LIMITED BY THE ELEVATED NATURE OF THE
AVAILABLE INSTABILITY. WILL CONTINUE TO HIGHLIGHT THIS SMALL
POTENTIAL IN THE HWO.
UPDATE ISSUED AT 730 PM EDT MON JUL 2 2012
KAPX RADAR REMAINS NEAR ECHO-FREE SO FAR THIS EVENING...ALTHOUGH
THE FAR ERN EDGE OF A LINE OF UPSTREAM CONVECTION OVER WRN UPR
MICHIGAN AND ERN WISCONSIN IS JUST NOW STARTING TO SHOW UP ON THE
LAST FEW BASE REF FRAMES. THIS LINE OF CONVECTION IS FEEDING OFF A
STRONG CONVERGENCE LINE ENHANCED BY LAKE BREEZES AND FED BY 850 MB
THETA E AND INSTABILITY GRADIENTS. THE LINE IS ACTUALLY MAKING
LITTLE EASTWARD PROGRESS...BUT INSTEAD SEEMS TO CONTINUALLY BE
REFORMING RIGHT ALONG THE STAGNANT CONVERGENT/LAKE BREEZE LINE.
THERE REMAINS A SMALL CHANCE THAT REMNANTS OF THIS CONVECTION
COULD REACH OUR SW CWA THIS EVENING...AND WILL LEAVE THIS MENTION
OF WX/POPS IN THE FORECAST FOR NOW. REST OF OUR CWA WILL REMAIN
DRY FOR THE EVENING...AS TEMPS FALL OUT OF THE 80S AND THRU THE 70S.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 358 PM EDT MON JUL 2 2012
MID AFTERNOON SURFACE ANALYSIS SHOWS HIGH PRESSURE OVER THE GREAT
LAKES...WITH A WAVY FRONTAL BOUNDARY EXTENDING SOUTHEAST FROM LOW
PRESSURE OVER NORTH DAKOTA...ACROSS THE UPPER MISSISSIPPI VALLEY AND
INTO THE UPPER OHIO VALLEY. SPOTTY CONVECTION HAS BEEN FORMING TO
THE NORTH OF THE WARM FRONT ACROSS NORTHEAST WISCONSIN THROUGH THE
DAY. WATER VAPOR IMAGERY SHOWS A COUPLE OF VORTICITY CENTERS
ROTATING THROUGH THE MAIN UPPER RIDGE AXIS EXTENDING FROM THE
CENTRAL PLAINS NORTHWARD INTO NORTHWEST ONTARIO. ONE WAS OVER
EASTERN IOWA DRIFTING SOUTHEAST...THE SECOND WAS TRACKING EAST
ACROSS NORTHEAST MINNESOTA. BAND OF WARM ADVECTION MID CLOUDS WERE
OVER LAKE SUPERIOR/CENTRAL UPPER...WHILE HIGH BASED CU HAS FORMED
OVER NORTHEAST LOWER MICHIGAN WITH A LAKE BREEZE BOUNDARY MOVING
INLAND FROM LAKE HURON.
MAIN FORECAST CONCERN IN THE NEAR TERM WILL DEAL WITH CONVECTIVE
POTENTIAL...AND IS OFTEN THE CASE ACROSS NORTHERN MICHIGAN WILL
DEPEND ON EVOLUTION OF THINGS WELL OUTSIDE OF THE FORECAST AREA.
WILL BE WATCHING SEVERAL POSSIBILITIES FOR TONIGHT...FIRST IS WITH
VORTICITY CENTER CROSSING THE MINNESOTA ARROWHEAD AS IT IMPINGES
UPON 2500+J/KG MLCAPE ACROSS NORTHERN WISCONSIN. LOW LEVEL MOISTURE
CONVERGENCE HAS ALSO BEEN INCREASING WEST OF GRB ALONG OUTFLOW
BOUNDARY ARCING WESTWARD. EVEN IF ADDITIONAL THUNDERSTORMS CAN
DEVELOP...INSTABILITY REALLY FALLS OFF THE TABLE OVER NORTHERN LOWER
WHERE DEW POINTS ARE STILL MOSTLY IN THE 50S...SO ITS NOT CLEAR IF
PRECIPITATION WOULD BE DRAGGED ACROSS THE LAKE AND INTO NORTHWEST
LOWER. REGARDLESS...LATER THIS EVENING AS LOW LEVEL THETA-E
GRADIENT NUDGES EAST INTO LOWER MICHIGAN SHOULD BE AN INCREASED
CHANCE FOR SPOTTY THUNDERSTORMS TO DEVELOP ACROSS NORTHWEST LOWER.
MAIN SHOW STILL LOOKS TO BE OVERNIGHT INTO TUESDAY MORNING...AS
EXPECTED MCS DEVELOPMENT ACROSS THE EASTERN DAKOTAS/NORTHERN
MINNESOTA/NORTHWEST ONTARIO THIS EVENING SHOULD BE PROPAGATING
TOWARD NORTHERN MICHIGAN BY DAYBREAK TUESDAY. EXACT EVOLUTION OF
THIS SYSTEM WILL HAVE A HUGE IMPACT ON SENSIBLE WEATHER FOR
TUESDAY...WITH BIG TEMPERATURE BUST POTENTIAL DEPENDING ON HOW
QUICKLY (OR IF) CLOUD COVER CAN THIN OUT. SOME INDICATIONS OF A
CONVECTIVELY INDUCED VORTICITY CENTER ACCOMPANYING THE PRECIP SHIELD
INTO NORTHERN MICHIGAN...WHICH WOULD TEND TO KEEP SHOWERS/CLOUDS
HANGING ON FOR A GOOD PORTION OF THE DAY. CURRENT THINKING IS TO
BUMP POPS UP TO THE LIKELY CATEGORY ESPECIALLY FOR THE FIRST PART OF
THE DAY...AND TRY NOT TO GET TOO HUNG UP ON MESOSCALE SPECIFICS THIS
FAR OUT WITH RESPECT TO THINGS LIKE OUTFLOW BOUNDARY DISPOSITION.
WILL ALSO BE A LITTLE MORE CONSERVATIVE ON TEMPERATURES...WILL ALLOW
FOR SOME SUN IN THE AFTERNOON TO WARM TEMPERATURES INTO THE 80S...
BUT WILL AVOID 90+ READINGS FOR NOW UNTIL WE HAVE A BETTER IDEA ON
HEATING POTENTIAL (MCS CLOUD COVER THE USUAL CULPRIT BETWEEN A SUNNY
AND 92 DEGREE FORECAST VERSUS A CLOUDY/RAINY 75 DEGREE REALITY).
AS FOR SEVERE WEATHER CONCERNS...CAN ENVISION AN INITIAL CONCERN
WITH THE LEADING EDGE CONVECTION OF MCS WHICH COULD CARRY A
LINGERING WIND THREAT INTO THE FORECAST AREA EARLY TUESDAY MORNING
(ESPECIALLY NORTHWEST LOWER??). BUT BEYOND THAT WILL HAVE TO WAIT
AND SEE HOW AFTERNOON EVOLVES.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 358 PM EDT MON JUL 2 2012
WELL ADVERTISED NORTHERN MICHIGAN MINI HEATWAVE STILL IN THE WORKS
THIS WEEK AS PLAINS HEAT DOME IS FORCED TO FOLD OVER THE REGION...
PUSHED ALONG BY ROUNDS OF ENERGY PUSHING IN FROM THE PACIFIC. STILL
WELL AGREED UPON EVIDENCE OF PATTERN RETROGRESSION THIS UPCOMING
WEEKEND INTO EARLY NEXT WEEK AS RIDGING BUILDS BACK INTO THE HIGH
PLAINS/INTERMOUNTAIN WEST...PLACING THE NORTH WOODS UNDER "COOLER"
NORTHWEST FLOW ALOFT. FORECAST CONCERNS THROUGH THE DURATION ARE
TWO-FOLD...CENTERING ON PERIODIC RAIN CHANCES...AND PROBABLY MOST
IMPORTANTLY...JUST HOW WARM TO GO WITH TEMPERATURES BOTH THURSDAY
AND FRIDAY.
DECENT START TO THE EXTENDED PERIOD...ALTHOUGH COULD SEE A FEW
LINGERING SHOWER AND STORMS TUESDAY NIGHT ALONG SOUTHWARD DROPPING
SURFACE TROUGH AXIS/COOL FRONT (COLD POOL ENHANCED?). EXIT OF MID
LEVEL SUPPORT EARLY IN THE EVENING AND LOSS OF DIURNALLY DRIVEN
INSTABILITY LIKELY TO KEEP COVERAGE OF ACTIVITY IN CHECK. DEPENDING
ON YOUR TEMPERATURE TOLERANCE...4TH OF JULY SHAPING UP TO BE AN
EXCELLENT DAY FOR OUTDOOR FESTIVITIES AS PUSH OF SOMEWHAT DRIER AIR
FOLLOWS TUESDAY NIGHTS SURFACE TROUGH AND MID LEVEL RIDGING BEGINS
TO BUILD OVERHEAD. PLENTY OF SUN AND MAINTENANCE OF OFF THE DECK
WARM TEMPERATURE PROFILES EASILY SUPPORT HIGHS WELL INTO THE
80S...WITH EVEN A FEW LOCALES PUSHING 90 DEGREES OVER NORTHERN
LOWER. LIGHT WIND FIELDS SHOULD SUPPORT AFTERNOON LAKE BREEZE
DEVELOPMENT... ALLOWING THE BIG LAKES REFRIGERATORS TO KEEP
SHORELINE COMMUNITIES A TOUCH COOLER.
HEAT TAKES CENTER STAGE TO END THE WORK WEEK...AS UPSTREAM HEAT DOME
FOLDS OVER...SPIKING 850MB AND 925MB TEMPERATURES WELL INTO THE 20S
CELSIUS. INCREASINGLY CAPPED ATMOSPHERE SHOULD KEEP MOST AREAS
DRY...WITH PERHAPS A FEW SHOWERS AND STORMS SCRAPPING BY EASTERN
UPPER WHERE QUASI-STATIONARY FRONTAL BOUNDARY AND SOUTHERN EXTENT OF
FAST MID LEVEL FLOW WILL RESIDE. PLENTY OF SUNSHINE AND WARM
TEMPERATURES MENTIONED ABOVE CONTINUE TO SUPPORT HIGHS IN THE 80S
AND LOWER 90S...WITH EVEN A FEW MIDDLE 90S POSSIBLE BY FRIDAY IN THE
FAVORED WARMER LOCALES OF NORTHEAST LOWER. COMBINE THE ABOVE WITH
DEW POINTS LIKELY IN THE MID AND UPPER 60S...AND HEAT INDEX VALUES
COULD APPROACH THE CENTURY MARK IN PARTS OF NORTHERN LOWER FRIDAY
AFTERNOON. WILL INTRODUCE THIS POTENTIAL IN THE LATEST RENDITION OF
THE HAZARDOUS WEATHER OUTLOOK. NORTHERN LAKES FRONT GETS THE BOOT
SOUTH FRIDAY NIGHT INTO SATURDAY MORNING AS EARLIER MENTIONED
PATTERN RETROGRESSION BEGINS. THIS SHOULD INCREASE THE POTENTIAL
FOR ANOTHER ROUND OF SHOWERS AND STORMS...ESPECIALLY IF ANY MCS
FORMS UPSTREAM AND SLIDES EAST ALONG THE BOUNDARY. CANADIAN HIGH
PRESSURE BUILDS IN LATER SATURDAY AND SUNDAY...BRINGING WITH IT DRY
WEATHER AND MUCH MORE BEARABLE TEMPERATURES...WITH HIGHS BY SUNDAY
BACK DOWN INTO THE 70S AND LOWER 80S. THESE TRENDS CONTINUE INTO THE
START OF NEXT WORK WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 143 AM EDT TUE JUL 3 2012
WX PATTERN WILL BECOME MORE ACTIVE LATE TONIGHT THRU TUESDAY
EVENING AS REMNANTS OF AN UPSTREAM MCS ARRIVE TOWARD SUNRISE
TUESDAY. ADDITIONAL CONVECTION WILL LIKELY DEVELOP THRU THE DAY ON
TUESDAY IN ADVANCE OF AN APPROACHING COOL FRONT. OVERALL
CONDITIONS WILL REMAIN VFR...ALTHOUGH CONDITIONS WILL DIMINISH TO
MVFR AND POSSIBLY IFR WITHIN ANY SHRA/TSRA THAT DEVELOPS LATER
TONIGHT AND TUESDAY. WINDS WILL REMAIN AOB 10 KTS THRU THE
FORECAST PERIOD...BUT STRONGER WINDS/WIND GUSTS ARE POSSIBLE WITH
ANY CONVECTION THAT DEVELOPS.
&&
.MARINE...
ISSUED AT 358 PM EDT MON JUL 2 2012
GENERALLY LIGHT SOUTHERLY GRADIENT WIND FORECAST TONIGHT THROUGH
TUESDAY...WITH HEADLINE CONDITIONS NOT ANTICIPATED. WINDS EXPECTED
TO VEER NORTHWEST TUESDAY NIGHT INTO WEDNESDAY...BUT AGAIN WINDS
SPEEDS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT CRITERIA.
HOWEVER...WINDS AND WAVES WILL BE HIGHER IN AND NEAR THUNDERSTORMS.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...SD
SYNOPSIS...FEF
SHORT TERM...JPB
LONG TERM...MSB
AVIATION...MR
MARINE...JPB
AREA FORECAST DISCUSSION
NWS DULUTH MN
322 PM CDT TUE JUL 3 2012
.SHORT TERM...HIGH PRESSURE WAS BUILDING OVER THE FA AT 19Z AS A
WEAK FRONTAL BOUNDARY LAY FAIRLY STATIONARY FROM THE MN ARROWHEAD
TO THE BRAINERD LAKES REGION. THE FRONT WILL WEAKEN TONIGHT. CU
FIELD DOTS THE FA AND WILL DISSIPATE NEAR SUNSET. CONVECTIVE
DEBRIS IN EASTERN ND WILL CONTINUE TO WEAKEN AS IT APPROACHES THE
FA. HAVE REMOVED MENTION OF PCPN FOR TONIGHT WHICH IS REFLECTED BY
THE LATEST HRRR AND LOCAL WRF. DID ADD PATCHY FOG FROM 08Z TO 12Z
WHICH IS INDICATED BY ALL MODELS.
LOW PRESSURE GETS ORGANIZED IN THE PLAINS ON WEDNESDAY AND ATTEMPTS
TO PUSH A WARM FRONT THROUGH MUCH OF THE FA. A SHORT WAVE WILL TRY
TO SUPPRESS THE UPPER LEVEL RIDGE BY WEDNESDAY AFTERNOON. THIS HAS
LEAD TO INCREASED POPS ALONG THE CANADIAN BORDER IN THE AFTERNOON.
ANOTHER WEAKER VORT MAX IS PROGGED TO INTERACT WITH THE FRONT IN NW
WI THROUGH THE DAY. THIS IS PICKED UP BY MOST OF THE MODELS AND HAVE
POPS INCREASING GRADUALLY.
A COLD FRONT WILL WORK ITS WAY THROUGH NE MN WEDNESDAY
EVENING...THEN WEAKEN AND STALL BY 12Z NEAR NW WI. MEANWHILE...THE
BEST UPPER LEVEL SUPPORT MOVES INTO CANADA THROUGH THE NIGHT. HAVE
HIGHEST POPS OVER NORTHERN HALF OF THE FA EARLY WHERE FORCING IS
MAXIMIZED...TRENDING DOWNWARD OVERNIGHT.
.LONG TERM...THURSDAY THROUGH MONDAY...
SYNOPTIC PATTERN FEATURES LARGE AMPLITUDE MID LVL RIDGE ACROSS CTRL
PLAINS THROUGH END OF WEEK. DURING THE WEEKEND MID LVL RIDGE AXIS
REDEVELOPS OVER WRN CONUS WITH A RELATIVE TROF OVER THE ERN PART OF
THE COUNTRY.THIS ALLOWS FOR AN INCREASINGLY STRONGER NW MID LVL FLOW
LATE WEEKEND INTO EARLY NEXT WEEK. THIS SHOULD ALSO KEEP HOT WEATHER
LOCATED SOUTH AND WEST OF REGION DURING THE WEEKEND. INITIAL SFC COLD
FRONT WILL PUSH ACROSS CWA THURSDAY WITH DRYING/NO POPS SPREADING
FROM NORTH TO SOUTH. REINFORCING SFC HIGH WILL SLIDE ACROSS SRN
CANADA AND INTO NRN PLAINS THROUGH MONDAY. THIS SHOULD MAINTAIN
HIGHEST INSTABILITY AND PWATS SOUTH OF REGION. POPS/QPF STILL
PROBLEMATIC AS MDL CONSENSUS STILL FAVORS PRECIP ACROSS SRN HALF OF
CWA. GENERAL IDEA IS THAT 85H THETAE AXIS/WARM FRONT WILL RESIDE
ALONG SRN EDGE OF WESTERLIES DURING FRIDAY/EARLY SUNDAY TIME FRAME.
CONFIDENCE IS NOT HIGH AT THIS POINT AS REALITY MAY BE QUITE
DIFFERENT WITH REGARD TO WHERE RING OF CONVECTION ACTUALLY OCCURS.
IT MAY BE THAT CORRIDOR OF PRECIP IS MORE NARROW IN AREAL EXTENT AND
IS FARTHER SOUTH THAN CURRENTLY FCST. THIS WOULD CHANGE CURRENT
UNSETTLED FCST TO A DRIER THEME AROUND TWIN PORTS/IRON RANGE
VICINITY. TEMPERATURES SHOULD LOWER TO MORE TYPICAL VALUES DURING
THE WEEKEND/EARLY NEXT WEEK.
&&
.AVIATION...18Z TAF ISSUANCE...
WEAK SFC BDRY IS PUSHING ACROSS CWA WITH SOME CU DEVELOPMENT
INCREASING ACROSS NRN/WRN CWA. MAIN ITEM OF INTEREST THIS PERIOD
IS AN ELONGATED AREA OF HIGHER INSTABILITY SOUTH OF REGION. THIS
REGION RETURNS NORTH OVERNIGHT. ALTHOUGH LITTLE FORCING SEEMS
AVAILABLE TO DEVELOP CONVECTION...HI RES MDLS SUGGEST THAT
POSSIBILITY EXISTS. CONFIDENCE IS NOT HIGH ENOUGH TO INSERT
CONVECTION IN MOST TERMINALS EXCEPT A CHANCE NEAR KBRD.
&&
.POINT TEMPS/POPS...
DLH 70 82 68 87 / 10 20 20 10
INL 67 90 65 91 / 10 40 70 10
BRD 73 94 70 91 / 10 20 30 30
HYR 72 92 73 93 / 10 40 20 20
ASX 67 81 68 87 / 10 20 20 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...HEAT ADVISORY UNTIL 10 PM CDT THURSDAY FOR MNZ033-034-036-038.
WI...HEAT ADVISORY UNTIL 10 PM CDT THURSDAY FOR WIZ006>009.
LS...NONE.
&&
$$
SHORT TERM...GSF
LONG TERM/AVIATION...CANNON
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1225 PM CDT TUE JUL 3 2012
.UPDATED FOR 18Z AVIATION DISCUSSION BELOW...
.DISCUSSION...
BIG HEADLINE FOR THIS FORECAST PERIOD IS THE SIGNIFICANT HEAT WAVE
THAT WILL BE ENVELOPING THE AREA THROUGH THURSDAY. HAVE UPGRADED
THE HEAT ADVISORY TO AN EXCESSIVE HEAT WARNING FOR THE ENTIRE AREA
FROM TODAY THROUGH THURSDAY.
THIS MORNING...30 KT LLJ HAS BEE SLOWLY PUSHING EAST ACROSS THE
AREA. STORMS INITIALLY FORMED ON THE NOSE OF THE JET UP TOWARD
BRAINERD. HOWEVER...WITH A COUPLE THOUSAND J/KG OF MUCAPE SITTING
ACROSS SRN MN...STORMS HAVE BEEN ABLE TO BUILD SOUTH INTO THE
LLJ. THIS BUILDING TO THE SOUTH IS LIKELY BEING AIDED BY OUTFLOW
PUSHING OUT OF THE MULTIPLE ROUNDS OF STORMS THAT HAVE GONE ACROSS
NRN MN. BY 18Z...THE RAP BASICALLY HAS THE LLJ AND ASSOCIATED
MOISTURE TRANSPORT OUT OF THE MPX AREA...SO THEREFORE EXPECT
ACTIVITY TO PUSH OUT OF THE MPX AREA BY THIS AFTERNOON. GIVEN THE
BOWING SEGMENTS WE HAVE SEEN ON RADAR...STRONG WINDS WILL BE A
CONTINUED THREAT THROUGH FOR A SHORT WHILE.
HEAT. SIGNIFICANT/HISTORIC HEAT WAVE WILL BE GRIPPING MUCH OF THE
MPX AREA THROUGH THURSDAY. GIVEN WHAT WAS OBSERVED YESTERDAY WITH
99S AT MSP AND EAU...GAVE TEMPS A GOOD BOOST THRU THURSDAY. BEST
GUIDANCE FOR WHAT WAS SEEN YESTERDAY WAS THE BIAS CORRECTED
VERSION OF THE NAM...AND THE NUMBERS IT HAS FOR THE NEXT 3 DAYS
ARE A BIT CONCERNING. WITH DEEP MIXING EXPECTED TO
CONTINUE...SHOULD CONTINUE TO SEE AFTERNOON DEWPS MIX DOWN INTO
THE UPPER 60S...WHICH WILL ALLOW TEMPS TO REALLY GET CRANKING.
FEELING PRETTY CONFIDENT THAT ACTUAL AIR TEMPS IN THE 100S WILL BE
COMMON ACROSS SRN MN INTO WI OVER THE NEXT 3 DAYS...WHICH WILL PUSH
APPARENT TEMPS UP TO 110. ADDING TO THE PROBLEM WILL BE OVERNIGHT
LOWS...WHICH OUTSIDE OF CENTRAL MN WILL ONLY FALL BACK INTO THE 75
TO 80 DEGREE RANGE...WITH MANY LOCATIONS WITHIN THE URBAN CENTER OF
THE TWIN CITIES LIKELY NOT FALLING BELOW 80 WITHOUT THE AID OF ANY
RAIN/OUTFLOW. GIVEN THE PROLONGED NATURE OF THE HEAT /4 DAYS
COUNTING MONDAY/...SAW NO REASON WHY WE SHOULD NOT UPGRADE THE
ADVISORY.
POPS WILL BE TRICKY OVER THE NEXT COUPLE OF DAYS AS ATMOSPHERE
WILL BE EXTREMELY UNSTABLE THANKS TO TEMPS UP AROUND 100 AND DEWPS
IN THE UPPER 60S. HOWEVER...A VERY WARM EML WITH H7 TEMPS UP
AROUND +14C WILL PROVIDE A VERY STOUT CAP FOR ANYTHING TO
OVERCOME. HARD PRESSED TO SEE MUCH CONVECTION OCCURRING IN THE MPX
AREA UNTIL THURSDAY AFTERNOON/NIGHT...WHEN THE H7 THERMAL RIDGE
FINALLY BEGINS TO BREAK DOWN. ONLY THING THAT COULD KEEP THE AREA
FROM BEING COMPLETELY DRY THIS AFTERNOON THRU WEDNESDAY IS IF WE
COULD GET SOME CONVECTION GOING WITHIN A LLJ AND WAA REGIME LIKE
THIS MORNING. THE BEST OPPORTUNITY FOR THIS WOULD COME WEDNESDAY
NIGHT...BUT LLJ JET LOOKS TO BE MORE ON THE ORDER OF 20 KTS AS
OPPOSED TO 30 KTS...WHICH SHOULD HELP KEEP THINGS DRY. AS WE GO
INTO THURSDAY AND ESPECIALLY THURSDAY NIGHT...THE THERMAL RIDGE
BEGINS TO BREAK DOWN AS A COLD FRONT SLIPS INTO CENTRAL MN.
CONCERN HERE IS THAT OFTEN TIMES WHEN YOU BURST A CAP TO END A
HEAT WAVE...THINGS CAN GET A BIT OUT OF HAND DUE THE INSTABILITY
PRESENT. THIS FRONT THEN STRUGGLES TO MOVE OUT OF THE MPX AREA
THROUGH THE WEEKEND AS THE UPPER RIDGE RETROGRADES FROM BEING
CENTERED UP THE MS VALLEY TO BEING CENTERED OVER THE ROCKIES. THIS
WILL RESULT IN PROGRESSIVELY MORE NW FLOW THROUGH THE
WEEKEND...WITH PRECIP CHANCES SLOWLY SAGGING SOUTH FRI/SAT.
AGAIN...WILL STILL BE PLENTY WARM/HUMID FRIDAY TO CREATE A VERY
UNSTABLE ENVIRONMENT...WITH AT LEAST A MARGINAL WIND/HAIL THREAT
EXISTING. GOING INTO THE WEEKEND...PERSISTENT N WINDS SHOULD
STARTING PULLING IN COOLER/DRIER AIR...WITH SEVERE THREAT
DIMINISHING AS A RESULT. MORE IMPORTANT THOUGH THAN THE
DIMINISHING RAIN CHANCES THIS WEEKEND...THE HEAT WAVE WILL HAVE
BEEN BROKEN...WITH HIGHS EXPECTED TO BE BACK NEAR NORMAL THAT WILL
PERSIST INTO NEXT WEEK.
&&
.AVIATION.../18Z TAF ISSUANCE/
FEW CUMULUS AND MID LEVEL CLOUDS REMAIN OVER PARTS OF THE AREA.
LOWER CUMULUS SHOULD LIFT O AROUND 5K FEET THIS AFTERNOON AND
GRADUALLY DISSIPATE IN THE VERY WARM AIRMASS. CLOUDS OVER THE SOUTH
ARE THINNING/ERODING AND WILL LIKELY CONTINUE. OTHERWISE MORE
MID/HIGH CLOUDS OVER THE DAKOTAS MAY WORK INTO THE AREA LATE
AFETRNOON/EVENING. SOME MODLES INDICATE SOME CONVECTION TO FIRE OVER
SOUTH DAKOTA AND LIFT NORTHEAST OVERNIGHT. WILL CONTINUE TREND OF
VC AT KAXN/KRWF/KSTC. THE REST OF THE AREA WILL BE LEFT DRY FOR
NOW. SOME MVFR HAZE AND BR POSSIBLE OVER EASTERN AREAS AFTER 07Z
WED WITH LIGHT WINDS AND HIGH DEPWOINTS REMAINING. THAT SHOULD ALL
BURN OFF THROUGH 13Z. WILL KEEP IT DRY THROUGH 18Z. WEAK SURFACE
BOUNDARY OVER WESTERN MN WILL MOVE SLOWLY SOUTH THIS AFTERNOON AND
SHOULD BECOME STATIONARY AND LIFT BACK NORTH INTO WEDNESDAY.
KMSP...SOUTHWEST TO WEST WIND AHEAD OF BOUNDARY THAT WILL SAG INTO
THE AREA THROUGH 00Z. LIGHT/VARIABLE WINDS IN THE EVENING WILL
BECOME MORE SOUTHEAST OVERNIGHT AND SOUTH INTO THE DAY
WEDNESDAY...GENERALLY LESS THAN 10 KNOTS. WITH LIGHT WINDS AND HIGH
DEWPTS WILL LIKELY SEE SOME HAZE IN THE MORNING BUT SHOULD REMAIN
DRY OVERNIGHT. SOME CHANCE OF SHOWER/THUNDER WEDNESDAY MORNING BUT
PROBABILITY LOW AT THIS TIME. AHEAD LIGHT NORTH/NORTHEAST WINDS
BEHIND BOUNDARY AND SOUTHWEST AHEAD OF IT.
OUTLOOK...
.WEDNESDAY...VFR. WINDS S 10-15 KT.
.THURSDAY...VFR. CHC SHOWER/TSTMS AFTERNOON/EVENG...WINDS S 10-20 KT.
.FRIDAY...VFR/MVFR. CHC SHWRS/TSTMS. SHIFTING WINDS...BECOMING NE
5-10 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...EXCESSIVE HEAT WARNING UNTIL 10 PM CDT THURSDAY FOR ANOKA-BENTON-
BLUE EARTH-BROWN-CARVER-CHIPPEWA-CHISAGO-DAKOTA-DOUGLAS-
FARIBAULT-FREEBORN-GOODHUE-HENNEPIN-ISANTI-KANABEC-
KANDIYOHI-LAC QUI PARLE-LE SUEUR-MARTIN-MCLEOD-MEEKER-MILLE
LACS-MORRISON-NICOLLET-POPE-RAMSEY-REDWOOD-RENVILLE-RICE-
SCOTT-SHERBURNE-SIBLEY-STEARNS-STEELE-STEVENS-SWIFT-TODD-
WASECA-WASHINGTON-WATONWAN-WRIGHT-YELLOW MEDICINE.
WI...EXCESSIVE HEAT WARNING UNTIL 10 PM CDT THURSDAY FOR BARRON-
CHIPPEWA-DUNN-EAU CLAIRE-PEPIN-PIERCE-POLK-RUSK-ST. CROIX.
&&
$$
MPG/
AREA FORECAST DISCUSSION...UPDATED FOR 12Z TAFS
NWS TWIN CITIES/CHANHASSEN MN
630 AM CDT TUE JUL 3 2012
.DISCUSSION...ISSUED 424 AM CDT
BIG HEADLINE FOR THIS FORECAST PERIOD IS THE SIGNIFICANT HEAT WAVE
THAT WILL BE ENVELOPING THE AREA THROUGH THURSDAY. HAVE UPGRADED
THE HEAT ADVISORY TO AN EXCESSIVE HEAT WARNING FOR THE ENTIRE AREA
FROM TODAY THROUGH THURSDAY.
THIS MORNING...30 KT LLJ HAS BEE SLOWLY PUSHING EAST ACROSS THE
AREA. STORMS INITIALLY FORMED ON THE NOSE OF THE JET UP TOWARD
BRAINERD. HOWEVER...WITH A COUPLE THOUSAND J/KG OF MUCAPE SITTING
ACROSS SRN MN...STORMS HAVE BEEN ABLE TO BUILD SOUTH INTO THE
LLJ. THIS BUILDING TO THE SOUTH IS LIKELY BEING AIDED BY OUTFLOW
PUSHING OUT OF THE MULTIPLE ROUNDS OF STORMS THAT HAVE GONE ACROSS
NRN MN. BY 18Z...THE RAP BASICALLY HAS THE LLJ AND ASSOCIATED
MOISTURE TRANSPORT OUT OF THE MPX AREA...SO THEREFORE EXPECT
ACTIVITY TO PUSH OUT OF THE MPX AREA BY THIS AFTERNOON. GIVEN THE
BOWING SEGMENTS WE HAVE SEEN ON RADAR...STRONG WINDS WILL BE A
CONTINUED THREAT THROUGH FOR A SHORT WHILE.
HEAT. SIGNIFICANT/HISTORIC HEAT WAVE WILL BE GRIPPING MUCH OF THE
MPX AREA THROUGH THURSDAY. GIVEN WHAT WAS OBSERVED YESTERDAY WITH
99S AT MSP AND EAU...GAVE TEMPS A GOOD BOOST THRU THURSDAY. BEST
GUIDANCE FOR WHAT WAS SEEN YESTERDAY WAS THE BIAS CORRECTED
VERSION OF THE NAM...AND THE NUMBERS IT HAS FOR THE NEXT 3 DAYS
ARE A BIT CONCERNING. WITH DEEP MIXING EXPECTED TO
CONTINUE...SHOULD CONTINUE TO SEE AFTERNOON DEWPS MIX DOWN INTO
THE UPPER 60S...WHICH WILL ALLOW TEMPS TO REALLY GET CRANKING.
FEELING PRETTY CONFIDENT THAT ACTUAL AIR TEMPS IN THE 100S WILL BE
COMMON ACROSS SRN MN INTO WI OVER THE NEXT 3 DAYS...WHICH WILL PUSH
APPARENT TEMPS UP TO 110. ADDING TO THE PROBLEM WILL BE OVERNIGHT
LOWS...WHICH OUTSIDE OF CENTRAL MN WILL ONLY FALL BACK INTO THE 75
TO 80 DEGREE RANGE...WITH MANY LOCATIONS WITHIN THE URBAN CENTER OF
THE TWIN CITIES LIKELY NOT FALLING BELOW 80 WITHOUT THE AID OF ANY
RAIN/OUTFLOW. GIVEN THE PROLONGED NATURE OF THE HEAT /4 DAYS
COUNTING MONDAY/...SAW NO REASON WHY WE SHOULD NOT UPGRADE THE
ADVISORY.
POPS WILL BE TRICKY OVER THE NEXT COUPLE OF DAYS AS ATMOSPHERE
WILL BE EXTREMELY UNSTABLE THANKS TO TEMPS UP AROUND 100 AND DEWPS
IN THE UPPER 60S. HOWEVER...A VERY WARM EML WITH H7 TEMPS UP
AROUND +14C WILL PROVIDE A VERY STOUT CAP FOR ANYTHING TO
OVERCOME. HARD PRESSED TO SEE MUCH CONVECTION OCCURRING IN THE MPX
AREA UNTIL THURSDAY AFTERNOON/NIGHT...WHEN THE H7 THERMAL RIDGE
FINALLY BEGINS TO BREAK DOWN. ONLY THING THAT COULD KEEP THE AREA
FROM BEING COMPLETELY DRY THIS AFTERNOON THRU WEDNESDAY IS IF WE
COULD GET SOME CONVECTION GOING WITHIN A LLJ AND WAA REGIME LIKE
THIS MORNING. THE BEST OPPORTUNITY FOR THIS WOULD COME WEDNESDAY
NIGHT...BUT LLJ JET LOOKS TO BE MORE ON THE ORDER OF 20 KTS AS
OPPOSED TO 30 KTS...WHICH SHOULD HELP KEEP THINGS DRY. AS WE GO
INTO THURSDAY AND ESPECIALLY THURSDAY NIGHT...THE THERMAL RIDGE
BEGINS TO BREAK DOWN AS A COLD FRONT SLIPS INTO CENTRAL MN.
CONCERN HERE IS THAT OFTEN TIMES WHEN YOU BURST A CAP TO END A
HEAT WAVE...THINGS CAN GET A BIT OUT OF HAND DUE THE INSTABILITY
PRESENT. THIS FRONT THEN STRUGGLES TO MOVE OUT OF THE MPX AREA
THROUGH THE WEEKEND AS THE UPPER RIDGE RETROGRADES FROM BEING
CENTERED UP THE MS VALLEY TO BEING CENTERED OVER THE ROCKIES. THIS
WILL RESULT IN PROGRESSIVELY MORE NW FLOW THROUGH THE
WEEKEND...WITH PRECIP CHANCES SLOWLY SAGGING SOUTH FRI/SAT.
AGAIN...WILL STILL BE PLENTY WARM/HUMID FRIDAY TO CREATE A VERY
UNSTABLE ENVIRONMENT...WITH AT LEAST A MARGINAL WIND/HAIL THREAT
EXISTING. GOING INTO THE WEEKEND...PERSISTENT N WINDS SHOULD
STARTING PULLING IN COOLER/DRIER AIR...WITH SEVERE THREAT
DIMINISHING AS A RESULT. MORE IMPORTANT THOUGH THAN THE
DIMINISHING RAIN CHANCES THIS WEEKEND...THE HEAT WAVE WILL HAVE
BEEN BROKEN...WITH HIGHS EXPECTED TO BE BACK NEAR NORMAL THAT WILL
PERSIST INTO NEXT WEEK.
&&
.AVIATION.../12Z TAF ISSUANCE/
REMNANTS OF OVERNITE TSTMS ARE EXITING THE AREA WITH JUST A SMALL
CHANCE OF A SHRA/TSTM AT EAU WITHIN THE NEXT HOUR. HIGH PRESSURE IN
WAKE OF TSTMS NOW SLIDING SE ACROSS WI. WINDS A BIT OF A CHALLENGE
IN FORECAST. MPX 12Z RAOB AND VAD WINDS SHOW BAND OF 20 TO 25 KTS
WINDS VEERING FROM SE TO SW BETWEEN WI HIGH PRESSURE AND LOW
PRESSURE IN SE SODAK. GRADIENT RELAXES DURING THE MORNING...BUT SFC
WINDS AND MSP/RNH/EAU WILL BE IN THE 12 TO 15 KT RANGE. SURFACE
ANALYSIS ALSO SHOWS WEAK TROF FROM INL TO MOX TO CNB. MODELS SAG
THIS SE AS HIGH PRESSURE MOVES ACROSS MB/SASK INTO NW OT DURING THE
DAY WITH WINDS BECOMING NW IN WAKE OF TROF. NOT A LOT OF CONFIDENCE
ON TIMING OF WIND SHIFT AS WINDS THEN SWING AROUND TO THE SE TO SW
AS WARM FRONT BEGINS TO LIFT NORTH. ATMOS SHUD BE CAPPED DURING THE
DAY TO INHIBIT ANY CONVECTIONS...BUT WITH PLUME OF MID/HIGH LEVEL
MOISTURE FROM SW U.S. INTO MN...WOULDN`T RULE OUT TSTMS
OVERNITE...MAINLY AT AXN.
MSP...WINDS WILL BE THE MAIN CHALLENGE. SE WINDS (120-150) SHUD
BEGIN TO BECOME MORE SWLY BY 15Z AS SW WINDS OFF SURFACE BEGIN TO
MIX DOWN ANSD AND WI HI PRESSURE SLIDES EAST. WEAK SFC TROF
MENTIONED IN ABOVE AVIATION DISC MAY ALSO REACH MSP LATE IN AFTN
CAUSING WSW WINDS FOR A FEW HOURS.
OUTLOOK...
.WEDNESDAY...VFR. WINDS S 10-15 KT.
.THURSDAY...VFR. WINDS S 10-20 KT.
.FRIDAY...VFR/MVFR. CHC SHWRS/TSTMS. SHIFTING WINDS...BECOMING NE
5-10 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...EXCESSIVE HEAT WARNING UNTIL 10 PM CDT THURSDAY FOR ANOKA-BENTON-
BLUE EARTH-BROWN-CARVER-CHIPPEWA-CHISAGO-DAKOTA-DOUGLAS-
FARIBAULT-FREEBORN-GOODHUE-HENNEPIN-ISANTI-KANABEC-
KANDIYOHI-LAC QUI PARLE-LE SUEUR-MARTIN-MCLEOD-MEEKER-MILLE
LACS-MORRISON-NICOLLET-POPE-RAMSEY-REDWOOD-RENVILLE-RICE-
SCOTT-SHERBURNE-SIBLEY-STEARNS-STEELE-STEVENS-SWIFT-TODD-
WASECA-WASHINGTON-WATONWAN-WRIGHT-YELLOW MEDICINE.
WI...EXCESSIVE HEAT WARNING UNTIL 10 PM CDT THURSDAY FOR BARRON-
CHIPPEWA-DUNN-EAU CLAIRE-PEPIN-PIERCE-POLK-RUSK-ST. CROIX.
&&
$$
MPG/JPC
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
424 AM CDT TUE JUL 3 2012
.DISCUSSION...
BIG HEADLINE FOR THIS FORECAST PERIOD IS THE SIGNIFICANT HEAT WAVE
THAT WILL BE ENVELOPING THE AREA THROUGH THURSDAY. HAVE UPGRADED
THE HEAT ADVISORY TO AN EXCESSIVE HEAT WARNING FOR THE ENTIRE AREA
FROM TODAY THROUGH THURSDAY.
THIS MORNING...30 KT LLJ HAS BEE SLOWLY PUSHING EAST ACROSS THE
AREA. STORMS INITIALLY FORMED ON THE NOSE OF THE JET UP TOWARD
BRAINERD. HOWEVER...WITH A COUPLE THOUSAND J/KG OF MUCAPE SITTING
ACROSS SRN MN...STORMS HAVE BEEN ABLE TO BUILD SOUTH INTO THE
LLJ. THIS BUILDING TO THE SOUTH IS LIKELY BEING AIDED BY OUTFLOW
PUSHING OUT OF THE MULTIPLE ROUNDS OF STORMS THAT HAVE GONE ACROSS
NRN MN. BY 18Z...THE RAP BASICALLY HAS THE LLJ AND ASSOCIATED
MOISTURE TRANSPORT OUT OF THE MPX AREA...SO THEREFORE EXPECT
ACTIVITY TO PUSH OUT OF THE MPX AREA BY THIS AFTERNOON. GIVEN THE
BOWING SEGMENTS WE HAVE SEEN ON RADAR...STRONG WINDS WILL BE A
CONTINUED THREAT THROUGH FOR A SHORT WHILE.
HEAT. SIGNIFICANT/HISTORIC HEAT WAVE WILL BE GRIPPING MUCH OF THE
MPX AREA THROUGH THURSDAY. GIVEN WHAT WAS OBSERVED YESTERDAY WITH
99S AT MSP AND EAU...GAVE TEMPS A GOOD BOOST THRU THURSDAY. BEST
GUIDANCE FOR WHAT WAS SEEN YESTERDAY WAS THE BIAS CORRECTED
VERSION OF THE NAM...AND THE NUMBERS IT HAS FOR THE NEXT 3 DAYS
ARE A BIT CONCERNING. WITH DEEP MIXING EXPECTED TO
CONTINUE...SHOULD CONTINUE TO SEE AFTERNOON DEWPS MIX DOWN INTO
THE UPPER 60S...WHICH WILL ALLOW TEMPS TO REALLY GET CRANKING.
FEELING PRETTY CONFIDENT THAT ACTUAL AIR TEMPS IN THE 100S WILL BE
COMMON ACROSS SRN MN INTO WI OVER THE NEXT 3 DAYS...WHICH WILL PUSH
APPARENT TEMPS UP TO 110. ADDING TO THE PROBLEM WILL BE OVERNIGHT
LOWS...WHICH OUTSIDE OF CENTRAL MN WILL ONLY FALL BACK INTO THE 75
TO 80 DEGREE RANGE...WITH MANY LOCATIONS WITHIN THE URBAN CENTER OF
THE TWIN CITIES LIKELY NOT FALLING BELOW 80 WITHOUT THE AID OF ANY
RAIN/OUTFLOW. GIVEN THE PROLONGED NATURE OF THE HEAT /4 DAYS
COUNTING MONDAY/...SAW NO REASON WHY WE SHOULD NOT UPGRADE THE
ADVISORY.
POPS WILL BE TRICKY OVER THE NEXT COUPLE OF DAYS AS ATMOSPHERE
WILL BE EXTREMELY UNSTABLE THANKS TO TEMPS UP AROUND 100 AND DEWPS
IN THE UPPER 60S. HOWEVER...A VERY WARM EML WITH H7 TEMPS UP
AROUND +14C WILL PROVIDE A VERY STOUT CAP FOR ANYTHING TO
OVERCOME. HARD PRESSED TO SEE MUCH CONVECTION OCCURRING IN THE MPX
AREA UNTIL THURSDAY AFTERNOON/NIGHT...WHEN THE H7 THERMAL RIDGE
FINALLY BEGINS TO BREAK DOWN. ONLY THING THAT COULD KEEP THE AREA
FROM BEING COMPLETELY DRY THIS AFTERNOON THRU WEDNESDAY IS IF WE
COULD GET SOME CONVECTION GOING WITHIN A LLJ AND WAA REGIME LIKE
THIS MORNING. THE BEST OPPORTUNITY FOR THIS WOULD COME WEDNESDAY
NIGHT...BUT LLJ JET LOOKS TO BE MORE ON THE ORDER OF 20 KTS AS
OPPOSED TO 30 KTS...WHICH SHOULD HELP KEEP THINGS DRY. AS WE GO
INTO THURSDAY AND ESPECIALLY THURSDAY NIGHT...THE THERMAL RIDGE
BEGINS TO BREAK DOWN AS A COLD FRONT SLIPS INTO CENTRAL MN.
CONCERN HERE IS THAT OFTEN TIMES WHEN YOU BURST A CAP TO END A
HEAT WAVE...THINGS CAN GET A BIT OUT OF HAND DUE THE INSTABILITY
PRESENT. THIS FRONT THEN STRUGGLES TO MOVE OUT OF THE MPX AREA
THROUGH THE WEEKEND AS THE UPPER RIDGE RETROGRADES FROM BEING
CENTERED UP THE MS VALLEY TO BEING CENTERED OVER THE ROCKIES. THIS
WILL RESULT IN PROGRESSIVELY MORE NW FLOW THROUGH THE
WEEKEND...WITH PRECIP CHANCES SLOWLY SAGGING SOUTH FRI/SAT.
AGAIN...WILL STILL BE PLENTY WARM/HUMID FRIDAY TO CREATE A VERY
UNSTABLE ENVIRONMENT...WITH AT LEAST A MARGINAL WIND/HAIL THREAT
EXISTING. GOING INTO THE WEEKEND...PERSISTENT N WINDS SHOULD
STARTING PULLING IN COOLER/DRIER AIR...WITH SEVERE THREAT
DIMINISHING AS A RESULT. MORE IMPORTANT THOUGH THAN THE
DIMINISHING RAIN CHANCES THIS WEEKEND...THE HEAT WAVE WILL HAVE
BEEN BROKEN...WITH HIGHS EXPECTED TO BE BACK NEAR NORMAL THAT WILL
PERSIST INTO NEXT WEEK.
&&
.AVIATION.../06Z TAF ISSUANCE/
WITH A WMFNT NE OF TAF SITES AND CDFNT NW OF TAF SITES...MUCH OF
THE AREA WILL REMAIN WARM...HUMID AND UNSTABLE. HOWEVER...WITH
PRIMARY LIFTNG MECHANISMS JUST N OF THE SITES...AM NOT EXPECTING
THE ONGOING CONVECTION OVER NRN MN AND NW WI NOR ANY POTENTIAL
LATER DEVELOPMENT DURING THE OVERNIGHT HOURS TO IMPACT THE
TERMINALS SINCE THERE IS LITTLE LOW LEVEL CONVERGENCE. HAVE KEPT
THE TAFS DRY WITH MULTIPLE MID- AND HIGH-LAYER CLOUDS. SMALL
POTENTIAL THERE COULD BE SOME FOG/HAZE OVERNIGHT WITH SUCH A MOIST
ATMOS IN PLACE...ESP SHOULD WINDS DROP TO CALM...BUT CHCS ARE NOT
GREAT...ESPECIALLY WITH LEFTOVER OUTFLOW BOUNDARIES KEEPING THINGS
MIXED. MORE STABLE AIR DURG THE DAY TDA WILL KEEP CONVECTION FROM
BREAKING OUT...ALLOWING FOR SLOWLY CLEARING SKIES LATE TDA INTO
TNGT.
MSP...VFR CONDITIONS THROUGHOUT THIS TAF SET THOUGH THERE WILL BE
PLENTY OF MID- AND UPPER-LEVEL CLOUDS PASSING BY AS CONVECTION TO
THE N PERSISTS THROUGH AT LEAST THE EARLY MORNING HOURS. NOT
LOOKING FOR THE CONVECTION TO REACH MSP...BUT DEBRIS CLOUDS ARE A
GOOD POSSIBILITY. CLOUDS THEN LINGER THROUGH MUCH OF THE DAY BUT
MAY PARTIALLY CLEAR OUT LATE. WINDS WILL SWING AROUND...INCLUDING
GOING TO N NOT LONG AFTER THIS TAF ISSUANCE DUE TO A SWD-MOVING
OUTFLOW BOUNDARY. WINDS WILL THEN RETURN TO THE PREDOMINANTLY SLY
DIRECTION BY DAYBREAK...THEN GRADUALLY SHIFT TO SW AND NW. SPEEDS
WILL GENERALLY REMAIN BELOW 10 KT...WITH SOME SLIGHTLY HIGHER
GUSTS POSSIBLE THIS AFTN.
OUTLOOK...
.WEDNESDAY...VFR. WINDS SE 10-15 KT.
.THURSDAY...VFR. WINDS S 10-20 KT.
.FRIDAY...VFR/MVFR. CHC SHWRS/TSTMS. SHIFTING WINDS...BECOMING NE
5-10 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...EXCESSIVE HEAT WARNING UNTIL 10 PM CDT THURSDAY FOR ANOKA-BENTON-
BLUE EARTH-BROWN-CARVER-CHIPPEWA-CHISAGO-DAKOTA-DOUGLAS-
FARIBAULT-FREEBORN-GOODHUE-HENNEPIN-ISANTI-KANABEC-
KANDIYOHI-LAC QUI PARLE-LE SUEUR-MARTIN-MCLEOD-MEEKER-MILLE
LACS-MORRISON-NICOLLET-POPE-RAMSEY-REDWOOD-RENVILLE-RICE-
SCOTT-SHERBURNE-SIBLEY-STEARNS-STEELE-STEVENS-SWIFT-TODD-
WASECA-WASHINGTON-WATONWAN-WRIGHT-YELLOW MEDICINE.
WI...EXCESSIVE HEAT WARNING UNTIL 10 PM CDT THURSDAY FOR BARRON-
CHIPPEWA-DUNN-EAU CLAIRE-PEPIN-PIERCE-POLK-RUSK-ST. CROIX.
&&
$$
MPG/JPC
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1049 AM CDT TUE JUL 3 2012
.DISCUSSION...MID AND UPPER LEVEL RIDGING REMAINS FIRMLY ENTRENCHED
OVER THE AREA TODAY. VISIBLE SATELLITE IMAGERY SHOWS SOME MID TO
HIGH CLOUDS OVER WESTERN PORTIONS OF THE CWA. THIS WAS HOLDING TEMPS
DOWN A FEW DEGREES IN THESE AREAS. ELSEWHERE READINGS HAD ALREADY
REACHED 90 DEGREES BY 15Z. GIVEN THE IMPACT OF THE CLOUDS...HAVE
LOWERED MAX TEMPS FOR TODAY BY A FEW DEGREES ACROSS PARTS OF THE
WEST. OTHERWISE FORECAST HIGH TEMPS APPEAR TO BE ON TRACK.
WITH RESPECT TO RAIN CHANCES FOR TODAY...MOST MODEL GUIDANCE
CONTINUES TO SUGGEST THE BEST CHANCES WILL BE ACROSS THE SOUTH AND
EAST. WILL ALSO HAVE TO WATCH FOR POTENTIAL DEVELOPMENT ALONG THE
DIFFERENTIAL HEATING BOUNDARY AT THE EDGE OF THE CLOUD SHIELD CLOSER
TO THE MS RIVER. RECENT HRRR RUNS HAVE HINTED AT THIS BEING A
POSSIBILITY. AS HAS BEEN THE CASE OVER THE PAST FEW DAYS...DECENT
INSTABILITY WILL CREATE A THREAT FOR A FEW STRONG STORMS. OVERALL
THOUGH...THE CURRENT POP/WX GRIDS APPEAR TO HAVE A GOOD HANDLE ON
THE SITUATION AND NO ADJUSTMENTS WILL BE MADE AT THIS TIME.
UPDATED FORECAST PRODUCTS HAVE BEEN SENT AND AN UPDATED AVIATION
DISCUSSION FOLLOWS BELOW. /DL/
&&
.AVIATION...MOSTLY VFR CONDITIONS WILL PREVAIL TODAY. IT APPEARS THE
BEST TSTM CHANCES FOR THIS AFTN/EVNG WILL BE FOR SOUTHEAST MS AND
THE HBG AREA...PERHAPS AS FAR NORTHWEST AS JAN/HKS. BUT A STRAY TSTM
WILL BE POSSIBLE AT ANY LOCATION IN THE HOT AND UNSTABLE AIRMASS. IF
A STORM DEVELOPS...IT COULD BRING BRIEF MVFR/IFR VIS RESTRICTIONS.
/28/
&&
.PREV DISCUSSION... /ISSUED AT 410 AM CDT TUE JUL 3 2012/
SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT...A HOT AND MOSTLY DRY
PATTERN WILL CONTINUE THROUGH MID WEEK AS THE SUBTROPICAL HIGH
EXERTS STRONG INFLUENCE ON ARKLAMISS WEATHER. OVER THE NEXT COUPLE
OF DAYS...MODELS AGREE THAT THE CENTER OF THE HIGH WILL SET UP OVER
MISSOURI WITH A RIDGE EXTENDING SOUTHWARD ALONG THE MS RIVER. THIS
WILL ENSURE ABOVE NORMAL HIGH TEMPERATURES...BUT LOW TEMPERATURES
WILL DIP INTO THE UPPER 60S/LOWER 70S AND LOW-LEVEL MIXING DURING
THE DAY WILL BE SUFFICIENT TO KEEP HEAT STRESS BELOW HEAT ADVISORY
CRITERIA.
THUNDERSTORM POTENTIAL FOR WEDNESDAY AFTERNOON/EVENING COULD BE A
LITTLE GREATER AS MODEL GUIDANCE SHOWS THE SURFACE HIGH SHIFTING
EAST...THUS ALLOWING FOR BETTER LOW LEVEL MOISTURE CONVERGENCE.
CONTINUED HOT SFC TEMPS AND HIGH DCAPE VALUES WOULD SUPPORT
STRONG/SVR MICROBURST ACTIVITY AGAIN...BUT WILL HOLD OFF ON ANY
MENTION IN THE HWO YET. /EC/
LONG TERM...THURSDAY THROUGH NEXT TUESDAY...COMPUTER MODELS STILL IN
PRETTY DECENT AGREEMENT THROUGH THE BULK OF THE LONG TERM PERIOD
ABOUT NASTY SUBTROPICAL RIDGE CENTER REPOSITIONING TO OUR NORTHWEST
LATE THIS WEEK AND INTO THE WEEKEND. THIS WILL ALLOW AT LEAST MINOR
DISTURBANCES TO ROTATE CLOCKWISE AROUND SAID RIDGE CENTER AND ACROSS
OUR REGION WHILE THE ATMOSPHERE OVER MOST OF THE ARKLAMISS
MOISTENS...STAYS UNSTABLE...AND GENERALLY RIPENS FOR CONVECTION.
AFTERNOON AND EVENING SHOWER AND THUNDERSTORM ACTIVITY MAY REALLY
ONLY INCREASE SOME ON THURSDAY IN MAINLY SOUTHEAST MS...BUT FRIDAY
AND SATURDAY HAVE POTENTIAL TO FEATURE LOTS OF MAINLY LATE DAY
STORMS OVER A BULK OF THE AREA.
IT IS AT THIS POINT THAT CURRENT EURO/GFS/GFSENSEMBLE MEAN SUGGEST A
LARGER DISTURBANCE THAT PREVIOUSLY BREAKS OFF FROM THE WESTERLIES
FAR TO THE NORTH WILL ROTATE AROUND THE RIDGE AND AFFECT THE LOWER
MS VALLEY. IF THIS OCCURS AS PLANNED THEN THE ADDED LIFT AND MODEST
SHEAR OVER THE REGION COULD RESULT IN ONE OR TWO THUNDERSTORM
COMPLEX PASSAGES BETWEEN FRIDAY AND SATURDAY ACROSS AT LEAST
PORTIONS OF THE ARKLAMISS. A POSSIBLE DOWNSIDE IS THAT EVEN IF THIS
AGGRESSIVE EVOLUTION TAKES PLACE THERE IS POTENTIAL THAT AT LEAST MY
ARKLAMISS DELTA ZONES COULD REMAIN TOO CLOSE TO THE HOT AND DRY
RIDGE CENTER TO SEE A WHOLE LOT OF BENEFIT. THAT WOULD BE
UNFORTUNATE BECAUSE THOSE MENTIONED DELTA SPOTS DEFINITELY ARE MOST
BEHIND IN THE PRECIP DEPARTMENT.
TEMPERATURES SHOULD REMAIN HOT THURSDAY THROUGH SATURDAY AWAY FROM
STORMS...ESPECIALLY IN NORTHWESTERN ZONES WHERE STORM COVERAGE WILL
LIKELY BE LEAST AND WHAT ACTIVITY THERE IS COULD WAIT UNTIL VERY
LATE IN THE AFTERNOON. IT IS IN THOSE NORTHWEST ZONES WHERE SOME
HIGHS UP NEAR 100 STILL SEEMS POSSIBLE AT LEAST THROUGH THURSDAY AND
FRIDAY. ELSEWHERE...THE HEAT WILL BE SOMEWHAT LESS AND WILL TEND TO
BE BROKEN BY PATCHES OF CLOUDS AND SHOWERS AND STORMS IN THE
AFTERNOON (ESPECIALLY FRIDAY AND SATURDAY).
LATEST LOOK OF A CONSOLIDATED DISTURBANCE COMING THROUGH FRIDAY AND
SATURDAY INCREASES POTENTIAL FOR AT LEAST SOME SEVERE STORM ACTIVITY
OVER THIS PERIOD GIVEN THE HIGH LAPSE RATE ENVIRONMENT AND PROSPECT
OF AT LEAST SOME LOOSE STORM ORGANIZATION. I AM NOT QUITE CONVINCED
OF THIS CONSOLIDATED DISTURBANCE YET SO WILL HOLD OFF MENTIONING
JUST YET IN THE HWO. HOWEVER...EVEN WEAKER DISTURBANCES WOULD STILL
BE TRIGGERING ISOLATED TO SCATTERED AFTERNOON STORMS IN AN UNSTABLE
ENVIRONMENT AND THUS A FEW COULD STILL BE POTENT IN THE EVENT OF A
TAMER EVOLUTION.
BY SUNDAY AND THROUGH THE FIRST OF NEXT WEEK THE EURO MODEL REALLY
SPLITS WITH THE GFS AND ITS ENSEMBLE MEAN...WITH THE EURO SHOWING
HOT SUBTROPICAL RIDGING TRYING TO BUILD BACK INTO THE SOUTHEAST
WHILE THE GFS SIDE ADVERTISES A LARGE SCALE EAST COAST TROUGH. THE
GFS SOLUTION WOULD ALSO SUGGEST THE SLOW SAG OF A COLD FRONT INTO
THE REGION DURING THIS TIME FRAME...RESULTING IN LOTS OF CONVECTION
AND A LITTLE COOLER TEMPS. TOO EARLY TO SAY WHICH SOLUTION IS
CORRECT...BUT SLIGHTLY ABOVE CLIMO MEX POPS ACCEPTED FOR NOW. /BB/
&&
.FIRE WEATHER...WE WILL CONTINUE TO ISSUE A FIRE DANGER STATEMENT AS
MANY LOCATIONS AROUND THE ARKLAMISS ARE UNDER BURN BANS. MOST
LOCATIONS ARE WELL BELOW NORMAL IN RAINFALL FOR THE PAST MONTH AND
NO SIGNIFICANT RAINFALL COVERAGE IS EXPECTED IN THE NEAR TERM. HOT
AND GENERALLY DRY CONDITIONS WILL CONTINUE FOR THE NEXT SEVERAL
DAYS. /EC/
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
DL/JC/EC/BB
AREA FORECAST DISCUSSION
NWS JACKSON MS
410 AM CDT TUE JUL 3 2012
.SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT...A HOT AND MOSTLY DRY
PATTERN WILL CONTINUE THROUGH MID WEEK AS THE SUBTROPICAL HIGH
EXERTS STRONG INFLUENCE ON ARKLAMISS WEATHER. OVER THE NEXT COUPLE
OF DAYS...MODELS AGREE THAT THE CENTER OF THE HIGH WILL SET UP OVER
MISSOURI WITH A RIDGE EXTENDING SOUTHWARD ALONG THE MS RIVER. THIS
WILL ENSURE ABOVE NORMAL HIGH TEMPERATURES...BUT LOW TEMPERATURES
WILL DIP INTO THE UPPER 60S/LOWER 70S AND LOW-LEVEL MIXING DURING
THE DAY WILL BE SUFFICIENT TO KEEP HEAT STRESS BELOW HEAT ADVISORY
CRITERIA.
AS FOR THUNDERSTORM CHANCES...BOUNDARIES THAT MAY SERVE AS FOCI FOR
CONVECTIVE DEVELOPMENT ARE DIFFICULT TO ASCERTAIN THIS MORNING. IN
FACT...SURFACE HIGH PRESSURE AND ANTICYCLONIC FLOW WILL BE CENTERED
RIGHT OVER THE ARKLAMISS TODAY AND HAVE KEPT PRECIP CHANCES VERY LOW
AS A RESULT. SLIGHTLY HIGHER POPS ARE INDICATED OVER SE PORTIONS
OF THE AREA...WHERE SEABREEZE-RELATED BOUNDARIES COULD EVENTUALLY
HAVE AN IMPACT. WRF AND HRRR GUIDANCE GENERALLY SUPPORT THIS
THINKING.
WHILE MID LEVEL LAPSE RATES ARE NOT VERY IMPRESSIVE...HOT SURFACE
TEMPERATURES WILL YIELD STEEP LOW LEVEL LAPSE RATES AND DEEP
SUB-CLOUD LAYERS SUPPORTIVE OF STRONG TO POSSIBLY SEVERE
MICROBURSTS. WITH DCAPE VALUES EXPECTED TO APPROACH 1500 J/KG...WILL
MENTION THE POSSIBILITY OF A FEW STRONG TO SEVERE TSTMS IN THE
HWO/GRAPHICS IN AREAS...PARTICULARLY IN THE LAUREL/HATTIESBURG/
BROOKHAVEN/NATCHEZ AREA. EXPECT ANY STORMS TO DIMINISH QUICKLY AFTER
SUNSET WITH QUIET OVERNIGHT CONDITIONS ANTICIPATED.
THUNDERSTORM POTENTIAL FOR WEDNESDAY AFTERNOON/EVENING COULD BE A
LITTLE GREATER AS MODEL GUIDANCE SHOWS THE SURFACE HIGH SHIFTING
EAST...THUS ALLOWING FOR BETTER LOW LEVEL MOISTURE CONVERGENCE.
CONTINUED HOT SFC TEMPS AND HIGH DCAPE VALUES WOULD SUPPORT
STRONG/SVR MICROBURST ACTIVITY AGAIN...BUT WILL HOLD OFF ON ANY
MENTION IN THE HWO YET. /EC/
.LONG TERM...THURSDAY THROUGH NEXT TUESDAY...COMPUTER MODELS STILL
IN PRETTY DECENT AGREEMENT THROUGH THE BULK OF THE LONG TERM PERIOD
ABOUT NASTY SUBTROPICAL RIDGE CENTER REPOSITIONING TO OUR NORTHWEST
LATE THIS WEEK AND INTO THE WEEKEND. THIS WILL ALLOW AT LEAST MINOR
DISTURBANCES TO ROTATE CLOCKWISE AROUND SAID RIDGE CENTER AND ACROSS
OUR REGION WHILE THE ATMOSPHERE OVER MOST OF THE ARKLAMISS
MOISTENS...STAYS UNSTABLE...AND GENERALLY RIPENS FOR CONVECTION.
AFTERNOON AND EVENING SHOWER AND THUNDERSTORM ACTIVITY MAY REALLY
ONLY INCREASE SOME ON THURSDAY IN MAINLY SOUTHEAST MS...BUT FRIDAY
AND SATURDAY HAVE POTENTIAL TO FEATURE LOTS OF MAINLY LATE DAY
STORMS OVER A BULK OF THE AREA.
IT IS AT THIS POINT THAT CURRENT EURO/GFS/GFSENSEMBLE MEAN SUGGEST A
LARGER DISTURBANCE THAT PREVIOUSLY BREAKS OFF FROM THE WESTERLIES
FAR TO THE NORTH WILL ROTATE AROUND THE RIDGE AND AFFECT THE LOWER
MS VALLEY. IF THIS OCCURS AS PLANNED THEN THE ADDED LIFT AND MODEST
SHEAR OVER THE REGION COULD RESULT IN ONE OR TWO THUNDERSTORM
COMPLEX PASSAGES BETWEEN FRIDAY AND SATURDAY ACROSS AT LEAST
PORTIONS OF THE ARKLAMISS. A POSSIBLE DOWNSIDE IS THAT EVEN IF THIS
AGGRESSIVE EVOLUTION TAKES PLACE THERE IS POTENTIAL THAT AT LEAST MY
ARKLAMISS DELTA ZONES COULD REMAIN TOO CLOSE TO THE HOT AND DRY
RIDGE CENTER TO SEE A WHOLE LOT OF BENEFIT. THAT WOULD BE
UNFORTUNATE BECAUSE THOSE MENTIONED DELTA SPOTS DEFINITELY ARE MOST
BEHIND IN THE PRECIP DEPARTMENT.
TEMPERATURES SHOULD REMAIN HOT THURSDAY THROUGH SATURDAY AWAY FROM
STORMS...ESPECIALLY IN NORTHWESTERN ZONES WHERE STORM COVERAGE WILL
LIKELY BE LEAST AND WHAT ACTIVITY THERE IS COULD WAIT UNTIL VERY
LATE IN THE AFTERNOON. IT IS IN THOSE NORTHWEST ZONES WHERE SOME
HIGHS UP NEAR 100 STILL SEEMS POSSIBLE AT LEAST THROUGH THURSDAY AND
FRIDAY. ELSEWHERE...THE HEAT WILL BE SOMEWHAT LESS AND WILL TEND TO
BE BROKEN BY PATCHES OF CLOUDS AND SHOWERS AND STORMS IN THE
AFTERNOON (ESPECIALLY FRIDAY AND SATURDAY).
LATEST LOOK OF A CONSOLIDATED DISTURBANCE COMING THROUGH FRIDAY AND
SATURDAY INCREASES POTENTIAL FOR AT LEAST SOME SEVERE STORM ACTIVITY
OVER THIS PERIOD GIVEN THE HIGH LAPSE RATE ENVIRONMENT AND PROSPECT
OF AT LEAST SOME LOOSE STORM ORGANIZATION. I AM NOT QUITE CONVINCED
OF THIS CONSOLIDATED DISTURBANCE YET SO WILL HOLD OFF MENTIONING
JUST YET IN THE HWO. HOWEVER...EVEN WEAKER DISTURBANCES WOULD STILL
BE TRIGGERING ISOLATED TO SCATTERED AFTERNOON STORMS IN AN UNSTABLE
ENVIRONMENT AND THUS A FEW COULD STILL BE POTENT IN THE EVENT OF A
TAMER EVOLUTION.
BY SUNDAY AND THROUGH THE FIRST OF NEXT WEEK THE EURO MODEL REALLY
SPLITS WITH THE GFS AND ITS ENSEMBLE MEAN...WITH THE EURO SHOWING
HOT SUBTROPICAL RIDGING TRYING TO BUILD BACK INTO THE SOUTHEAST
WHILE THE GFS SIDE ADVERTISES A LARGE SCALE EAST COAST TROUGH. THE
GFS SOLUTION WOULD ALSO SUGGEST THE SLOW SAG OF A COLD FRONT INTO
THE REGION DURING THIS TIME FRAME...RESULTING IN LOTS OF CONVECTION
AND A LITTLE COOLER TEMPS. TOO EARLY TO SAY WHICH SOLUTION IS
CORRECT...BUT SLIGHTLY ABOVE CLIMO MEX POPS ACCEPTED FOR NOW. /BB/
&&
.AVIATION...FAIRLY TYPICAL HOT/HAZY AIRMASS OVER THE ARKLAMISS
CONTINUES WITH MOSTLY VFR CONDITIONS AND OCCASIONAL MVFR CONDITIONS
WHERE HAZE REDUCES VISIBILITY. EARLY MORNING FOG ADDED TO THE MIX IS
RESULTING INTO LOCALIZED AREAS OF IFR VSBY...BUT EXPECT THIS TO MIX
OUT SHORTLY AFTER SUNRISE. IT APPEARS THE BEST TSTM CHANCES FOR THIS
AFTN/EVNG WILL BE FOR SOUTHEAST MS AND THE HBG AREA...PERHAPS AS FAR
NORTHWEST AS JAN/HKS. BUT A STRAY TSTM WILL BE POSSIBLE AT ANY
LOCATION IN THE HOT AND UNSTABLE AIRMASS. /EC/
&&
.FIRE WEATHER...WE WILL CONTINUE TO ISSUE A FIRE DANGER STATEMENT AS
MANY LOCATIONS AROUND THE ARKLAMISS ARE UNDER BURN BANS. MOST
LOCATIONS ARE WELL BELOW NORMAL IN RAINFALL FOR THE PAST MONTH AND
NO SIGNIFICANT RAINFALL COVERAGE IS EXPECTED IN THE NEAR TERM. HOT
AND GENERALLY DRY CONDITIONS WILL CONTINUE FOR THE NEXT SEVERAL
DAYS. /EC/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 98 71 98 72 / 10 14 18 9
MERIDIAN 98 68 98 70 / 20 18 23 18
VICKSBURG 97 70 96 71 / 8 13 13 7
HATTIESBURG 98 72 97 73 / 26 20 25 21
NATCHEZ 95 72 94 72 / 15 13 19 16
GREENVILLE 99 74 98 74 / 8 8 10 7
GREENWOOD 98 71 97 73 / 8 9 12 9
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
EC/BB
AREA FORECAST DISCUSSION
NWS BILLINGS MT
1106 PM MDT MON JUL 2 2012
.SHORT TERM...VALID FOR TUE AND WED...
QUICK UPDATE THIS EVENING TO INCREASE POPS IN EXTREME SOUTHEASTERN
MONTANA... AND PORTIONS OF NORTHERN WYOMING...IN RESPONSE TO CURRENT
THUNDERSTORM ACTIVITY IN THOSE AREAS. AAG
...PREVIOUS DISCUSSION...
UPPER SOUTHWEST FLOW ALOFT OVER THE FORECAST AREA WITH SEVERAL
IMPULSES PUSHING ACROSS THE REGION. ISOLATED SHOWERS AND
THUNDERSTORMS HAVE DEVELOPED OVER PORTIONS OF NORTHERN WYOMING
THIS EVENING BUT HAVE WEAKEN AS THEY LIFT NORTHEAST INTO BIG HORN
AND TREASURE COUNTIES. SATELLITE SHOWING CONVECTION DEVELOPING
OVER SOUTHWEST MONTANA THIS EVENING WITH ANOTHER SHORT WAVE. A
FEW ISOLATED SHOWERS/THUNDERSTORMS WILL BE POSSIBLE OVER THE FAR
WESTERN AND CENTRAL ZONES THROUGH LATE EVENING AND WILL KEEP A
SLIGHT CHANCE POPS GOING. THE BETTER CHANCE FOR PRECIPITATION
TONIGHT WILL BE FROM SHERIDAN TO EKALAKA WHERE MODELS ARE
FORECASTING A STRONGER SHORT WAVE. CONVECTION WILL BE WEAK BUT
ANY STORMS THAT DEVELOP WILL BE WET. HRRR CONTINUING TO INDICATE
SHOWERS AND THUNDERSTORMS FROM SHERIDAN TO EKALAKA OVERNIGHT
WHICH INCREASES CONFIDENCE FOR KEEPING SCATTERED POPS GOING IN
THIS AREA OVERNIGHT.
NO CHANGE TO THE RED FLAG WARNING FOR TUESDAY AS HOT
TEMPERATURES... LOW HUMIDITIES AND GUSTY WINDS WILL BE OVER THE
ENTIRE FORECAST AREA. 00Z WRF BRINGING A COLD FRONT THROUGH
BILLINGS AROUND 6 PM. STRONG PRE-FRONTAL MIXING WILL ALLOW
TEMPERATURES TO REACH THE CENTURY MARK OVER MANY LOCATION
TOMORROW. ISOLATED THUNDERSTORMS WILL ALSO BE POSSIBLE WITH THE
FRONTAL PASSAGE. RICHMOND
.LONG TERM...VALID FOR THU...FRI...SAT...SUN...MON...
MODELS ARE IN PRETTY GOOD AGREEMENT WITH THE OVERALL
PATTERN/REGIME THROUGH THE EXTENDED...THE DIFFERENCES ARE IN
DETAILS SUCH AS SHORTWAVE TIMING AND STRENGTH.
THE THEME FOR THE EXTENDED IS UPPER LEVEL RIDGING BUILDING OVER
THE CENTRAL PLAINS...THEN SLOWLY RETROGRADING WESTWARD THROUGH
TIME. THIS PUTS THE BILLINGS CWA IN SOUTHWESTERLY FLOW. SHORTWAVES
IN THIS FLOW WILL TAP INTO AND TRANSPORT MONSOONAL MOISTURE FROM
THE SW CONUS NORTHWARD INTO THE REGION. AT THE SAME
TIME...A PREDOMINANT SOUTHEAST TO EAST LOW LEVEL WIND WILL SET UP
ACROSS THE REGION. THIS WILL BRING ADDITIONAL MOISTURE INTO THE
CWA. AS A RESULT OF THE SHORTWAVE ACTIVITY AND INCREASED LOW LEVEL
MOISTURE...AT LEAST ISOLATED SHOWERS AND THUNDERSTORMS WILL BE
POSSIBLE THROUGH THE PERIOD. CANNOT NECESSARILY NAIL DOWN TIMING
OF INDIVIDUAL SHORTWAVES AS THIS TIME...SO ESSENTIALLY KEPT SLIGHT
CHANCE TO CHANCE POPS IN THE FORECAST THROUGH THE EXTENDED...WITH
A FEW MINOR TWEAKS. THE THUNDERSTORM ACTIVITY DOES BRING WITH IT
AN INCREASED POTENTIAL OF LIGHTNING-GENERATED FIRE STARTS THROUGH
THE EXTENDED PERIOD...MUCH AS HAS BEEN OBSERVED WITH RECENT
CONVECTION.
WITH THE RIDGE RETROGRADING WESTWARD...TEMPS LOOK TO BE QUITE
WARM. GIVEN THE TREND OF THE LAST SEVERAL WEEKS...TEMPS LOOKS TO
BE CLOSER TO BC GUIDANCE THAN NON-BC GUIDANCE...WHICH PUTS THEM
WARMER THAN WHAT WAS PREVIOUSLY FORECAST. THE ONE CAVEAT TO THIS
IS THE POSSIBILITY OF INCREASED CLOUD COVER. STILL...THINK LOW TO
MID 90S FOR HIGHS ARE NOT UNREASONABLE ACROSS MUCH OF SOUTHEAST
MONTANA...ESPECIALLY GIVEN THE FAIRLY WARM START TO EACH DAY IN
THE EXTENDED PERIOD WITH LOWS EXPECTED TO DROP ONLY INTO THE
UPPER 50S TO UPPER 60S. STC
&&
.AVIATION...
AN ISOLATED SHOWER OR THUNDERSTORM WILL BE POSSIBLE THIS EVENING
AND THROUGHOUT THE OVERNIGHT HOURS. THE BEST CHANCES WILL BE
ALONG AND EAST OF A KMLS-KSHR LINE. EXPECT GUSTY AND ERRATIC
WINDS IN AND NEAR ANY THUNDERSTORM ACTIVITY. OTHERWISE...SKIES
WILL BE MOSTLY CLEAR TONIGHT WITH VFR CONDITIONS PREVAILING.
HOOLEY
&&
.PRELIMINARY POINT TEMP/POPS...
TUE WED THU FRI SAT SUN MON
-----------------------------------------------------------
BIL 062/100 059/087 062/091 064/094 063/094 064/094 065/095
21/N 20/U 11/U 22/T 22/T 22/T 22/T
LVM 051/097 048/086 053/088 054/093 055/092 055/092 055/092
22/T 20/U 12/T 22/T 22/T 32/T 22/T
HDN 059/102 057/090 061/093 063/096 063/095 063/096 064/097
21/G 20/U 12/T 22/T 22/T 22/T 22/T
MLS 066/104 061/090 065/095 066/097 066/097 066/097 067/097
22/T 20/U 12/T 22/T 22/T 22/T 22/T
4BQ 063/101 060/090 063/094 067/093 065/094 064/095 064/095
82/T 20/U 22/T 22/T 32/T 32/T 22/T
BHK 061/100 061/089 063/091 065/092 063/092 063/093 064/093
33/T 21/N 22/T 23/T 33/T 32/T 22/T
SHR 057/101 053/090 060/091 060/093 060/092 061/092 061/093
81/G 20/U 22/T 23/T 22/T 32/T 32/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...RED FLAG WARNING IN EFFECT FROM NOON TUESDAY TO MIDNIGHT MDT
TUESDAY NIGHT FOR ZONES 123>133.
WY...RED FLAG WARNING IN EFFECT FROM NOON TUESDAY TO MIDNIGHT MDT
TUESDAY NIGHT FOR ZONES 274-284.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
652 PM CDT WED JUL 4 2012
.AVIATION...
CLUSTER OF STORMS OVER WESTERN NEBRASKA BETWEEN KANW AND KLBF WERE
PRODUCING BRIEF HEAVY RAIN MOSTLY SMALL HAIL AND GUSTY WINDS TO
45KTS. THESE STORMS WERE LOCATED ALONG A WEAK COLD FRONTAL
BOUNDARY. A GUST FRONT EXTENDS TO THE NORTH AND THE SOUTH OF THE
STORMS AND WILL AFFECT THE KLBF TAF SITE AROUND 0500Z TO 0501Z.
THINKING IS THAT STORMS WILL STAY NORTH OF KLBF TAF SITE. SOME
ISOLATED STORMS OVER SOUTHWEST NEBRASKA TO THE NORTHEAST OF KIML
AND OVER THE SOUTHERN NEBRASKA PANHANDLE. STORMS EXPECTED TO
DIMINISH THROUGH THE EVENING WITH VFR CONDITIONS OVER NIGHT AND
INTO THURSDAY AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 325 PM CDT WED JUL 4 2012/
DISCUSSION...
A COLD FRONT HAS BECOME STATIONARY FROM NEAR KOGA TO KTIF TO NEAR
KANW. THE FRONT IS EXPECTED TO BECOME THE FOCUS FOR ISOLATED TO
PERHAPS SCATTERED STRONG/SEVERE SLOW MOVING TSTMS LATE THIS AFTN
AND THIS EVENING. STORM DEVELOPMENT IS UNDERWAY. WEAKLY SHEARED
ENVIRONMENTAL WINDS AND DEEP VERTICAL MIXING SUGGEST THE
POTENTIAL FOR WIND DAMAGE AND HEAT BURSTS. THE HRRR INDICATES
PRECIPITABLE WATER NEAR OR ABOVE 1.5 INCHES SUPPORTING LOCALLY
HEAVY RAINFALL.
STORM ACTIVITY IS EXPECTED TO DEVELOP SOUTHEAST AND POSSIBLY
MERGE WITH ACTIVITY FCST TO SPREAD EAST THROUGH COLO AND INTO KS
LATE TONIGHT BEFORE DISSIPATING AFTER MIDNIGHT. THUS MOTHER NATURE
HAS ITS OWN FIRE WORKS SHOW PLANNED THIS EVENING AND VERY DRY AND
DUSTY CONDITIONS WILL SUPPORT STORMS CAPABLE OF DANGEROUS
LIGHTNING FOR ANYONE ATTENDING OUTDOOR EVENTS THIS EVENING.
THE STATIONARY FRONT IS EXPECTED TO LIFT NORTHWEST THURSDAY AND
THURSDAY NIGHT. TEMPERATURES ALONG AND SOUTH OF THE FRONT SHOULD
RISE INTO THE 100S ONCE AGAIN. NORTH OF THE FRONT ISOLATED TSTMS
MAY DEVELOP ACROSS NORTHWEST NEB ASSOCIATED WITH A PLUME OF
SUBTROPICAL MOISTURE AND WEAK PERTURBATIONS ROTATING NORTH AROUND
THE H500 MB RIDGE.
ANOTHER COLD FRONT WILL PUSH DOWN INTO THE FCST AREA FRIDAY
PRODUCING VERY WARM HIGHS SOUTH OF THE FRONT. THE NAM SUGGESTED
106 AT KONL AND THIS MIGHT NOT BE TOO FAR OFF THE MARK. FOR NOW
WILL FCST 104 AT KONL. NO PROBLEM WITH THE 102 FCST BY THE NAM AT
KLBF FOR FRIDAY. BASED ON THE TEMPERATURES THIS AFTN...105 AT KLBF
SO FAR...LATER FCSTS MAY HAVE TO MARK UP HIGHS FRIDAY. THE NAM AND
ECM ARE VERY DRY WITH THIS FRONT AND THE FCST FOLLOWS THE DRIER
SOLNS. THE HEAT ADVISORY HAS BEEN EXTENDED THROUGH FRIDAY.
THE UPPER LEVEL RIDGE CURRENTLY CENTERED OVER CNTL MISSOURI IS
FCST BUILD SLOWLY WEST FRIDAY THROUGH SUNDAY AND BE CENTERED OVER
UTAH BY MONDAY SETTING UP A NORTHWEST FLOW ALOFT THROUGHOUT THE
FCST AREA. THIS SHOULD HELP DRIVE A SIGNIFICANT COLD FRONT THROUGH
THE FCST AREA AND INTO KS FRIDAY FOR A SEMI PERMANENT COOL DOWN
LASTING SATURDAY THROUGH WEDNESDAY. HIGHS DURING THIS TIME PERIOD
SHOULD REMAIN NEAR NORMAL.
RAIN CHANCES ARE UNCERTAIN SUNDAY THROUGH WEDNESDAY BUT SEVERAL KEY
INGREDIENTS COULD CONSPIRE TO PRODUCE RAIN. THEY ARE UPSLOPE LOW
LEVEL MOISTURE FLOW...LOWER HEIGHTS ALOFT PRODUCING A WEAKER CAP
AND THE VERY UNCERTAIN POSSIBILITY OF DISTURBANCES DROPPING
SOUTHEAST OUT OF THE NRN PLAINS PRODUCING ISOLATED TO SCATTERED
STORM COVERAGE DAILY. THE GENERAL CONSENSUS BETWEEN THE ECM AND
GFS SUGGESTED THE BEST CHANCE OF RAIN WOULD GENERALLY BE ALONG
AND WEST OF HIGHWAY 61.
CLIMATE...
THIS IS THE THIRD DAY IN A ROW OF 100 PLUS TEMPERATURES AT NORTH
PLATTE. THIS STREAK IS FORECAST TO CONTINUE THROUGH FRIDAY WHICH
WOULD RIVAL THE GREAT HEAT WAVES OF 1934 (13 DAYS)...1935 (5
DAYS)...1936 (6 DAYS) AND 1955 (5 DAYS).
&&
.LBF WATCHES/WARNINGS/ADVISORIES...HEAT ADVISORY UNTIL 9 PM CDT FRIDAY
FOR NEZ005>010-025>029-037-038-059-070-071.
&&
$$
SHORT TERM/EXTENDED...CDC
AVIATION...POWER
AREA FORECAST DISCUSSION
NWS BUFFALO NY
754 PM EDT WED JUL 4 2012
.SYNOPSIS...
A WEAK COLD FRONT WILL CROSS THE AREA TONIGHT BRINGING THE POTENTIAL
FOR SCATTERED THUNDERSTORMS. BEHIND THE FRONT...FAIR WEATHER
CONDITIONS RETURN FOR THURSDAY AND FRIDAY AS HIGH PRESSURE BUILDS
OVER THE REGION.
&&
.NEAR TERM /THROUGH THURSDAY/...
THROUGH EARLY EVENING...THUNDERSTORMS HAVE MAINLY STAYED OUT OF
OUR CWA...THOUGH THERE WAS A FEW WIDELY SCATTERED STORMS ACROSS
PARTS OF THE SOUTHERN TIER AND EAST OF LAKE ONTARIO. MEANWHILE...A
BOUNDARY CONTINUES TO DROP SOUTHWARD ACROSS LAKE
ONTARIO...BRINGING IN DRIER AIR FROM THE NORTH. BOTH RADAR
TRENDS...AND RUNS OF THE HRRR SUPPORT A MAINLY DRY FORECAST
OVERNIGHT...OUTSIDE OF PERHAPS A STRAY SHOWER OR THUNDERSTORM THIS
EVENING AHEAD OF THIS BOUNDARY. FOR LOCATIONS NORTH OF THE THRUWAY
FROM BUFFALO TO ROCHESTER...THE CHANCES FOR ANYTHING THIS EVENING
APPEAR MINIMAL. UPDATE AGAIN TRENDS POPS DOWNWARD BASED ON THESE TRENDS.
OTHERWISE...EXPECT SKIES TO CLEAR OUT TONIGHT...AS SLIGHTLY COOLER
AND DRIER AIR MOVES IN. THIS SHOULD ALLOW TEMPERATURES TO DROP
INTO THE 60S IN MOST LOCATIONS...PERHAPS EVEN THE UPPER 50S EAST
OF LAKE ONTARIO. SOME PATCHY VALLEY FOG IS POSSIBLE IN THE
SOUTHERN TIER...ESPECIALLY WHERE SHOWERS MOVED THROUGH EARLIER
TODAY.
HIGH PRESSURE BUILDING DOWN ACROSS THE LOWER GREAT LAKES
THURSDAY WILL PROVIDED A FAIR WEATHER DAY. PLENTY OF SUNSHINE ALONG
WITH A MORE COMFORTABLE AIR MASS. MOST HIGHS IN THE UPPER 70S TO
LOWER 80S.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/...
THURSDAY NIGHT A STRONG UPPER LEVEL RIDGE WILL BE CENTERED OVER THE
CENTRAL U.S. CONTINUING TO BRING WELL ABOVE NORMAL TEMPERATURES TO
THE REGION. THIS UPPER RIDGING IS FORECAST TO EXPAND INTO THE
NORTHEAST REGION INCLUDING ACROSS NEW YORK THROUGH THE DAY FRIDAY.
MAINLY CLEAR SKIES WILL ALLOW FOR GOOD MIXING OF 850 MB TEMPS IN THE
RANGE OF 20C TO 22C FROM THE 12Z GFS. THIS WILL GIVE SURFACE TEMPS
IN THE LOW 90S ACROSS MUCH OF THE FORECAST AREA...10F TO 15F DEGREES
ABOVE NORMAL. CLOSER TO THE LAKES TEMPS IN THE UPPER 80S WILL BE
FOUND AND PARTS OF THE GENESEE VALLEY MAY TOUCH THE MID 90S. 12 GFS
BUFKIT PROFILES SHOW THE WARM 700-850MB AIR SHOULD KEEP A LID ON ANY
CONVECTION.
A CHANGE COMES ON FRIDAY NIGHT INTO SATURDAY AS A COLD FRONT SLIDES
SOUTH ACROSS THE GREAT LAKES FROM CENTRAL CANADA AND SETS UP ACROSS
WESTERN NY. THE 12Z NAM AND GFS BOTH SHOW ENOUGH LOW LEVEL MOISTURE
TO ALLOW FOR A CHANCE OF SHOWERS AND THUNDERSTORMS MAINLY SATURDAY
AHEAD OF AND ALONG THE FRONT. THE FRONT AND SIGNIFICANT CLOUD COVER
ALONG WITH LOWERING HEIGHTS ALOFT WILL HELP CUT BACK ON TEMPS
SATURDAY WITH HIGHS ONLY IN THE LOW 80S. LOWS OVER THE WEEKEND WILL
LIKELY BE IN THE LOW 60S AS DRY AIR IS NOT LOOKING TO BUILD IN UNTIL
SUNDAY.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
THE LONG TERM FORECAST CONTINUES TO LOOK LIKE A PERIOD OF NORMAL OR
BELOW NORMAL TEMPERATURES. UPPER LEVEL TROUGHING AND COOL AIR WILL
SETTLE OVER THE NORTHEAST BEHIND SATURDAYS COLD FRONT. DESPITE
COOLER TEMPS ALOFT MODELS ARE NOT SHOWING STRONG INDICATION OF ANY
CHANCE FOR RAIN UNTIL POSSIBLY LATE WEDNESDAY. SKIES WILL BE MAINLY
CLEAR WITH DAILY HIGHS RUNNING IN THE MIDDLE TO UPPER 70S...AROUND 5
DEGREES BELOW NORMAL AND OVERNIGHT LOWS IN THE MIDDLE TO UPPER 50S
AWAY FROM THE LAKES AND IN THE LOW 60S NEAR THE LAKES.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
A WEAK FRONTAL BOUNDARY WILL DROP ACROSS THE REGION THIS
EVENING...SHIFTING WINDS AT MOST TAF LOCATIONS. THERE MAY BE
AN ISOLATED SHOWER OR THUNDERSTORM AHEAD OF THE FRONT THIS
EVENING. OTHERWISE...EXPECT VFR CONDITIONS TONIGHT...EXCEPT AT JHW
WHERE FOG MAY DEVELOP LATE TONIGHT. WIDESPREAD VFR CONDITIONS
EXPECTED ON THURSDAY.
OUTLOOK...
THURSDAY NIGHT AND FRIDAY...VFR.
FRIDAY NIGHT AND SATURDAY...VFR WITH A CHC OF MVFR IN SHOWERS.
SUNDAY AND MONDAY...VFR.
&&
.MARINE...
WINDS AND WAVES ARE EXPECTED TO REMAIN BELOW SMALL CRAFT ADVISORY
CRITERIA THROUGH FRIDAY...UNDER STABLE OVERLAKE CONDITIONS.
HOWEVER...CLUSTERS OF SHOWERS AND THUNDERSTORMS LATE THIS AFTERNOON
AND EVENING WILL BRING THE POTENTIAL FOR LOCALLY HIGHER WINDS AND
WAVES.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TMA
NEAR TERM...APFFEL/TMA
SHORT TERM...SMITH
LONG TERM...SMITH
AVIATION...APFFEL
MARINE...TMA
AREA FORECAST DISCUSSION
NWS BUFFALO NY
606 PM EDT TUE JUL 3 2012
.SYNOPSIS...
A WARM FRONT WILL APPROACH THE REGION THIS EVENING AND CROSS THE
REGION TONIGHT...BRINGING THE LIKELIHOOD OF SHOWERS AND
THUNDERSTORMS. HOT AND HUMID CONDITIONS WILL RETURN FOR WEDNESDAY.
A WEAK COLD FRONT WILL APPROACH LATE IN THE DAY AND WEDNESDAY
EVENING...WITH SCATTERED THUNDERSTORMS POSSIBLE. BEHIND THE
FRONT...FAIR WEATHER CONDITIONS RETURN FOR THURSDAY.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
CONVECTION THIS EVENING CONTINUES TO BE A DIFFICULT
FORECAST...WITH MODEST INSTABILITY IN PLACE...AND THE FOCUS FOR
CONVECTION SUBTLE. AT 600 PM...THERE WAS TWO LINES OF SHOWERS WITH
EMBEDDED THUNDERSTORMS...ONE ACROSS THE SOUTHERN TIER...AND
ANOTHER ACROSS EASTERN LAKE ONTARIO. THESE BOTH SHOULD GRADUALLY
WEAKEN AND CONTINUE TO MOVE TO THE EAST. THE BIG QUESTION IS WHAT
WILL DEVELOP UPSTREAM. MODEL GUIDANCE IS LITERALLY ALL OVER THE
PLACE...AND UNFORTUNATELY THERE IS LITTLE TO GATHER FROM THIS.
THE 18Z NAM AND LATEST HRRR PROVIDE SOME USEFUL GUIDANCE...BUT
STILL BOTH HAVE NOTABLE ERRORS IN VERIFICATION ALREADY. SO TAKING
A STEP BACK...WATER VAPOR IMAGERY SHOWS A NOTABLE DRY SLOT ACROSS
THE UPPER LAKES...WITH THIS FORECAST TO DROP ACROSS THE REGION
LATE TONIGHT. THIS SHOULD LARGELY BRING AN END TO ANY SIGNIFICANT
THREAT FOR CONVECTION FROM WEST TO EAST AFTER MIDNIGHT. UNTIL
THEN...IT WILL HARD TO COMPLETELY RULE OUT A SHOWER OR
THUNDERSTORM...BUT RADAR TRENDS SUGGEST THE MOST ORGANIZED
CONVECTION IS DEVELOPING ACROSS EASTERN MICHIGAN AND FAR SOUTHERN
ONTARIO. FOLLOWING NAM/HRRR GUIDANCE...WHATEVER DOES DEVELOP HERE
SHOULD MOVE ESE...GRADUALLY VEERING TO THE RIGHT AND PERHAPS
CLIPPING FAR SW NEW YORK THIS EVENING. FORECAST UPDATE REFLECTS
THESE TRENDS...BUT KEEP IN MIND...ADDITIONAL DEVELOPMENT IS STILL
POSSIBLE DURING THE EVENING HOURS AHEAD OF THIS SHORTWAVE...SO
KEEP AT LEAST CHANCE POPS UNTIL DRIER AIR ALOFT MOVES IN.
IN AREAS WHERE THUNDERSTORMS DO DEVELOP SHEAR PROFILES STILL LOOK
FAVORABLE SO THINK THERE IS SOME POTENTIAL WIND THREAT IF
CONVECTION CAN MAINTAIN ITSELF. BIGGEST THREAT MAY BE WITH THE
POTENTIAL FOR HEAVY RAINFALL WITH PRECIPITABLE WATER VALUES
NEARING 2 INCHES. AT THIS TIME...THIS RISK LOOKS TO BE GREATER
SOUTH AND WEST OF OUR REGION...BUT PERHAPS WILL CLIP FAR
SOUTHWESTERN NEW YORK...UNLESS ADDITIONAL CONVECTION DEVELOPS.
IT WILL REMAIN WARM TONIGHT WITH LIGHT SOUTHERLY FLOW CONTINUING
THROUGH THE NIGHT. ABOVE NORMAL OVERNIGHT LOWS WILL RANGE FROM THE
MID 60S ALONG THE SOUTHERN TIER AND TUG HILL REGION...WHILE CLOSER
TO THE LAKES AND NORTHERN FINGER LAKES REGION LOWER TO MID 70S
WILL BE COMMON.
THE CONVECTIVE FORECAST LOOKS UNCERTAIN FOR THE INDEPENDENCE DAY
HOLIDAY. 12Z OPERATIONAL RUNS NOT REALLY DEPICTING A SIGNIFICANT
THERMAL BOUNDARY DROPPING THROUGH WESTERN AND CENTRAL NEW YORK
WEDNESDAY. HOWEVER...WIND AND MOISTURE FIELDS CLEARLY SHOW A BOUNDARY
WORKING THROUGH THE REGION DURING THE DAY. HOW MUCH CONVECTION THAT
WILL GET TRIGGERED IS HARD TO SAY. INSTABILITY WILL BUILD ACROSS THE
AREA IN A HOT AND HUMID AIRMASS...BUT LEFTOVER DEBRIS CLOUDS AND
OR PRECIPITATION COULD HAMPER SIGNIFICANT DESTABILIZATION. WEAK
SHORTWAVE DROPPING ACROSS THE REGION ALONG WITH LAKE BREEZE
BOUNDARIES WILL PROVIDE ADDITIONAL FORCING...WHICH WILL BE ENOUGH
SUPPORT TO MAINTAIN CHANCE PROBABILITIES. IF ENOUGH INSTABILITY
CAN BUILD THERE WILL BE SOME SEVERE POTENTIAL IF ORGANIZED
CONVECTION CAN DEVELOP. VERY WARM DAY IN STORE WITH MOST HIGHS IN
THE UPPER 80S TO THE LOWER 90S. DEWPOINTS IN AT LEAST THE MID 60S
WOULD PUSH APPARENT TEMPERATURES INTO THE LOWER TO MID 90S.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
WEDNESDAY NIGHT CHANCES FOR SHOWERS AND THUNDERSTORMS WILL LARGELY
BE OVER AS A WEAK COLD FRONT SHIFTS SOUTHEAST ACROSS NEW YORK.
EXPECT THE SKIES TO CLEAR FROM NORTHWEST TO SOUTHEAST OVERNIGHT AS
DRIER AIR BUILDS IN ALOFT. LOW TEMPERATURES STILL LOOK TO BE QUITE
WARM AND FEEL A BIT MUGGY AS THE WEAK FRONT WILL NOT MAKE MUCH OF A
DENT INTO DRYING OUT THE SURFACE LAYER. LOW TO MID 60S ACROSS INLAND
AREAS AND UPPER 60S TO MAYBE EVEN AROUND 70 ALONG THE LAKE SHORES.
THURSDAY AND FRIDAY WILL BRING A RETURN TO TEMPERATURES MUCH ABOVE NORMAL
AS UPPER LEVEL RIDING WHICH BROUGHT RECORD HIGHS TO THE CENTRAL U.S.
WORKS INTO NEW YORK. 500MB HEIGHTS WILL BUILD FROM AROUND 586 DM TO
NEAR 591 DM BY FRIDAY AFTERNOON. THESE HEIGHTS SUGGEST EXPANDING
HEAT IN THE LOWER HALF OF THE ATMOSPHERE. FOR 850 MB TEMPS WE ARE
LOOKING AT 14C TO 16C THURSDAY TO 19C TO 21C FOR FRIDAY. WITH MAINLY
CLEAR SKIES...MIXING THESE TEMPS DOWN TO THE SURFACE WILL YIELD HIGH
ON THURSDAY IN THE RANGE OF MIDDLE TO UPPER 80S ACROSS WESTERN NY
AND LOW 80S FOR AREAS EAST OF LAKE ONTARIO. ON FRIDAY HIGHS OF UPPER
80S TO LOW 90S LOOK LIKE A SURE BET. NORMAL HIGHS FOR EARLY JULY ARE
80F SO FORECAST TEMPS WILL BE ON THE ORDER OF 5F TO MAYBE AS MUCH AS
15F DEGREES ABOVE NORMAL. OVERNIGHT LOWS ON THURSDAY WILL REMAIN ON
THE WARM SIDE CLOSE TO THE LAKES WITH SOME UPPER 50S POSSIBLE ACROSS
THE SOUTHERN TIER AND EASTERN LAKE ONTARIO VALLEYS. WITH THE HOT
TEMPS OCCURRING FRIDAY...TEMPS FRIDAY NIGHT WILL BE VERY WARM AND
HUMID. NUMBERS WILL LIKELY NOT FALL BELOW 70 IN MANY SPOTS.
A STRONG UPPER LEVEL LOW VERTICALLY STACKED WITH A DEEP SURFACE LOW
MOVING ACROSS THE NORTHERN CANADIAN PRAIRIES ON THURSDAY AND FRIDAY
WILL BRING ANOTHER CHANGE TO THE FORECAST FRIDAY NIGHT. THE SURFACE
LOW WILL PUSH A COLD FRONT INTO THE GREAT LAKES. TIMING OF THE FRONT
AND ANY PRECIP IT MAY TRIGGER STILL NEEDS TO BE REFINED. SEEMS THE
12Z NAM IS A BIT QUICKER THAN THE 12Z GFS. BRINGING IN A CHANCE OF
SHOWERS FRIDAY AFTERNOON WHILE THE GFS HOLDS OFF UNTIL FRIDAY NIGHT.
HEDGED TOWARD THE GFS AND KEPT FORECAST DRY THROUGH FRIDAY.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
MODELS SHOW THE STRONG UPPER LOW SHIFTING ACROSS HUDSON BAY INTO
NORTHERN QUEBEC FRIDAY AND BY SATURDAY BOTH THE GFS AND ECMWF SHOW
THIS MERGING WITH A UPPER LOW OVER NOVA SCOTIA. THIS WILL RESULT IN
A COOLER UPPER LEVEL PATTERN WITH INCREASING TROUGHINESS DEVELOPING
THROUGH THE WEEKEND INTO EARLY NEXT WEEK. AT THE SURFACE A COLD
FRONT WILL SLIDE ACROSS NY ON SATURDAY. THIS FRONT PAIRED WITH
DECENT LOW LEVEL MOISTURE WILL ALLOW FOR CHANCES OF SHOWERS AND
THUNDERSTORMS SATURDAY AND SATURDAY NIGHT. BEHIND THIS FRONT THERE
APPEARS TO BE A DRY PERIOD SUNDAY INTO MONDAY. MODELS SHOW A
POSSIBLE SHORTWAVE DIGGING INTO THE UPPER TROUGH OVER THE AREA BY
TUESDAY SO INTRODUCED A SLIGHT CHANCE FOR SHOWERS AT THE END OF THE
LONG TERM PERIOD.
TEMPERATURE-WISE...SATURDAY WILL BE THE WARMEST DAY OF THE PERIOD
WITH HIGHS ONLY REACHING INTO THE LOWER TO MID 80S...SOME 10 DEGREES
COOLER THAN FRIDAY BEHIND THE FRONT. AS UPPER LEVEL TROUGHING
DEEPENS OVER THE NORTHEAST HIGH TEMPS WILL END UP NEAR TO BELOW
NORMAL. KEPT HIGHS IN THE UPPER 70S TO LOW 80S. OVERNIGHT LOWS FOR
SUNDAY THROUGH TUESDAY IN THE MID 50S WILL BE A RELIEF AFTER A FEW MUGGY
NIGHTS LATE THIS WEEK.
&&
.AVIATION /22Z TUESDAY THROUGH SUNDAY/...
EXPECT MAINLY VFR CONDITIONS THROUGH THIS EVENING...OUTSIDE OF
AREAS OF SHOWERS AND THUNDERSTORMS. THE MOST SIGNIFICANT AREA OF
THUNDERSTORMS WILL LIKELY DEVELOP ACROSS EASTERN MICHIGAN AND WILL
TRACK INTO FAR WESTERN NEW YORK THIS EVENING...POSSIBLY IMPACTING
JHW. OTHERWISE...ITS HARD TO COMPLETELY RULE OUT A SHOWER OR
THUNDERSTORM THIS EVENING. OTHERWISE...THE CHANCE FOR SHOWERS AND
THUNDERSTORMS DIMINISHES AFTER MIDNIGHT...THOUGHT HERE MAY BE
PATCHY FOG IN AREAS WHICH GET RAIN.
OUTLOOK...
WEDNESDAY...VFR. AREAS OF MVFR IN TSRA.
THURSDAY AND FRIDAY...VFR.
SATURDAY...VFR WITH A CHC OF MVFR IN SHOWERS.
SUNDAY...VFR.
&&
.MARINE...
WINDS AND WAVES ARE EXPECTED TO REMAIN BELOW SMALL CRAFT ADVISORY
CRITERIA THROUGH FRIDAY...UNDER STABLE OVERLAKE CONDITIONS.
HOWEVER...CLUSTERS OF SHOWERS AND THUNDERSTORMS TONIGHT AND
WEDNESDAY WILL BRING THE POTENTIAL FOR LOCALLY HIGHER WINDS AND
WAVES.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TMA
NEAR TERM...APFFEL/TMA
SHORT TERM...SMITH
LONG TERM...SMITH
AVIATION...APFFEL/TMA
MARINE...TMA
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
242 PM EDT TUE JUL 3 2012
.SYNOPSIS...
HIGH PRESSURE ALOFT OVER THE REGION WILL WEAKEN THROUGH MID WEEK.
AT THE SURFACE...BERMUDA HIGH PRESSURE AND THE PIEDMONT TROF WILL
AFFECT THE REGION THROUGHOUT THE FORECAST PERIOD. DAYTIME
TEMPERATURES ARE EXPECTED TO DROP TO SLIGHTLY ABOVE NORMAL VALUES
FOR EARLY JULY...WITH HUMID CONDITIONS CONTINUING TO PREVAIL. THE
PIEDMONT TROUGH AND THE SEA BREEZE WILL PROVIDE THE TRIGGER FOR
ISOLATED TO SCATTERED THUNDERSTORMS TO DEVELOP EACH AFTERNOON AND
EVENING THROUGH THE FORECAST PERIOD.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1:30 PM TUESDAY...CU DEVELOPMENT HAS BEEN QUITE MEAGER
CLOSER TO THE COAST BUT CU AND CONVECTION FLARING FURTHER INLAND
ALONG PIEDMONT TROUGH. HRRR SHOWS BEST CHC OF CONVECTION OVER OUR
LOCAL AREA WOULD BE IN THE GEORGETOWN WILLIAMSBURG AREA ALONG SEA
BREEZE BOUNDARY. OVERALL EXPECT ISOLATED COVERAGE. THE STEERING
FLOW REMAINS VERY WEAK OUT OF THE N-NW AND THEREFORE EXPECT ANY
STORMS MOVE SLOWLY TOWARD THE COAST WITH BEST CHC OVER WESTERN
COUNTIES THROUGH THIS EVENING.
LIGHT SOUTHWEST FLOW WILL CONTINUE THROUGH TONIGHT BETWEEN BERMUDA
HIGH AND PIEDMONT TROUGH INLAND. GUSTY WINDS ALONG THE COAST
ASSOCIATED WITH AFTERNOON SEA BREEZE WILL TAPER OFF SHORTLY AFTER
SUNSET ALLOWING FOR NEAR CALM WINDS ACROSS THE AREA. ANY CU BUILD
UP THIS AFTERNOON OR ISOLATED CONVECTION WILL ALSO COME TO AN END
LATE THIS EVENING. DRIER AIR AND SUBSIDENCE WILL CONTINUE ALOFT AS
MID TO UPPER RIDGE HOLDS ON THROUGH THE NIGHT.
TEMPS UP BETWEEN 90 AND 95 MOST PLACES THIS AFTERNOON WILL FALL
INTO THE 70S BY MORNING.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 2:30 PM TUESDAY...THE PIEDMONT TROUGH WILL REMAIN THE
DOMINANT SURFACE FEATURE THROUGH THE SHORT TERM WHERE IT COULD
BECOME THE MAIN FOCUS FOR INITIALIZATION OF CONVECTION ON BOTH
WEDNESDAY AND THURSDAY AFTERNOON AND EVENING. THE SEA BREEZE FRONT
MAY ALSO CONTRIBUTE AS A FOCUSING MECHANISM. A PERSISTENT STRONG
UPPER RIDGE WILL REMAIN POSITIONED FAR ENOUGH TO THE WEST SO THAT
IT WILL NOT KEEP A TOTAL LID ON CONVECTION...IN FACT THROUGH EARLY
THURSDAY WE WILL SEE A MORE TROUGH-LIKE PATTERN OVER THE EASTERN
SEABOARD AS THE EASTERN PERIPHERY OF THE RIDGE BECOMES SUPPRESSED
SOUTHWARDS. MODERATE TO STRONG INSTABILITY AND STRONG BOUNDARY
LEVEL HEATING WITH ATTENDANT STEEP LAPSE RATES ON BOTH DAYS WILL
KEEP THE ATMOSPHERE PRIMED FOR CONVECTION. IN ADDITION...THERE
WILL BE AMPLE LOW LEVEL MOISTURE FOR CONVECTION WITH P/W VALUES
BETWEEN 1.75 AND 2.00 INCHES THROUGH THE PERIOD.
OF PARTICULAR INTEREST WILL BE AN UPPER TROUGH THAT WILL DROP
SOUTHEAST ACROSS THE EASTERN CAROLINAS LATE WEDNESDAY/EARLY
THURSDAY. TIMING OF THE CONVECTION ASSOCIATED WITH THIS FEATURE
STILL UNCERTAIN SO HAVE GONE WITH GENERAL SCATTERED POPS FOR MUCH
OF WEDNESDAY AND THURSDAY...INCLUDING OVERNIGHT WEDNESDAY INTO
THURSDAY MORNING.
SUBSIDENCE ASSOCIATED WITH THE UPPER RIDGE WILL KEEP MAX
TEMPERATURES RUNNING ABOVE NORMAL WEDNESDAY AND THURSDAY...MAINLY
MID 90S WITH SOME UPPER 90S WELL INLAND. LOWS PRIMARILY IN THE MID
70S BOTH DAYS...WITH UPPER 70S AT THE BEACHES.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 2:30 PM TUESDAY...SHORTWAVE TROUGH WILL BE EXITING SOUTH AT THE
START OF THE PERIOD. THE EXACT TIMING OF THIS WILL DETERMINE THE
POP/CLOUDS ON FRIDAY. BEST OMEGA OCCURS EARLY FRIDAY...ESPECIALLY
ACROSS THE SOUTHERN ZONES...WITH SOME SUBSIDENCE/NVA DEVELOPING
BEHIND THIS FEATURE...DO NOT EXPECT WIDESPREAD TSTM COVERAGE...BUT
FEEL INHERITED LOW-CHANCE IS WARRANTED IN AN ENVIRONMENT
CHARACTERIZED BY HIGH THETA-E AIR IN THE PRESENCE OF THIS UPPER
IMPULSE. CONVECTION WILL BE DIURNALLY INFLUENCED...AND WILL WANE
WITH LOSS OF HEATING FRIDAY NIGHT.
LARGE UPPER RIDGE ACROSS THE MIDWEST BUILDS EAST INTO THE CAROLINAS
FOR THE WKND...BRINGING WARMING MID LEVEL TEMPS AND A WEAK CAP TO
CONVECTION FOR THE WKND. WITH A TYPICAL SUMMER-TIME SURFACE
PATTERN...THAT IS...BERMUDA HIGH TO THE EAST WITH PIEDMONT TROUGH TO
THE WEST...THERE STILL MAY BE DIURNALLY FORCED CONVECTION EACH DAY
ALONG THE PIEDMONT TROUGH AND SEA BREEZE BOUNDARY. WITH VERY DRY AIR
PRESENT IN FORECAST SOUNDINGS AND SUBSIDENCE OCCURRING BENEATH THE
RIDGE...WILL CAP POPS AT LOW SLIGHT CHANCE FOR ISOLATED THUNDERSTORMS.
A MORE POTENT SHORTWAVE DROPS SE EARLY MONDAY BETWEEN ERODING RIDGE
AND DEEPENING TROUGH TO THE NORTH. GFS APPEARS TO BE SUFFERING FROM
SOME CONVECTIVE FEEDBACK WITH ITS SOLUTION EARLY MONDAY...BUT ECMWF
ALSO SHOWS A SHORTWAVE IN THIS TIMEFRAME. THIS WILL ACT AS A FORCING
MECHANISM FOR RENEWED CONVECTION BEGINNING EARLY MONDAY...AND WILL
PUSH A FRONT (ALBEIT WITH LIMITED AIRMASS CHANGE) TOWARDS THE
REGION. THIS FRONT WILL STALL/WASH OUT OVER THE CAROLINAS THROUGH
TUESDAY AND PROVIDE AN ADDITIONAL MECHANISM FOR TSTMS MONDAY AND
TUESDAY. THERE IS POTENTIAL FOR MDT/HVY RAINFALL WITHIN CONVECTION
FOR THE FIRST PART OF NEXT WEEK DUE TO A HIGHLY SATURATED AIRMASS
(PWATS OVER 2 INCHES)...THE APPROACH OF A DIFLUENT JET REGION...AND
THE PRESENCE OF THIS FRONT. FOR NOW WILL SHOW TRWM AS WX TYPE SINCE
IT IS DAYS 6-7...BUT SIGNALS DO POINT TO AT LEAST THE POTENTIAL FOR
SOME DECENT RAINFALL MON/TUE.
MAX TEMPS WILL REMAIN SEVERAL DEGREES ABOVE CLIMO THROUGH
SUNDAY...DROPPING TO AROUND CLIMO FOR THE FIRST PART OF NEXT WEEK.
MINS WILL RUN SEVERAL DEGREES ABOVE DUE TO PERSISTENT SOUTHERLY
FLOW. ALTHOUGH HEAT INDICES WILL STILL BE HIGH...THEY WILL REMAIN
MOSTLY BELOW 105F EXCEPT ON SUNDAY WHEN HEAT ADVISORIES MAY BE
NEEDED FOR AREAS AWAY FROM THE COAST.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
AS OF 18Z...GOOD CAPE...BUT STRONG CONVECTIVE INHIBITION. LOOK FOR
LIGHT SOUTHWESTERLY FLOW TO SHIFT TO THE SOUTH ALONG THE COAST WITH
THE RESULTANT. AIR MASS SHOULD HAVE ENOUGH CAPE TO KICK OFF A STORM
OR TWO BY LATE AFTERNOON...BOTH ALONG THE SEA BREEZE BOUNDARY AND
INLAND. COVERAGE IS EXPECTED TO BE QUITE MINIMAL AT THIS TIME.
OVERNIGHT...LIGHT SOUTHWESTERLY FLOW WITH POSSIBLE MVFR HAZE/FOG
AFTER 08Z. WEDNESDAY...THERMAL TROUGH WILL CONTINUE TO GIVE US
SOUTHWESTERLY FLOW...PERHAPS A BIT STRONGER THAN TODAY. ISOLATED
CONVECTION EXPECTED BY THE END OF THE FORECAST PERIOD.
EXTENDED OUTLOOK...A CHANCE OF THUNDERSTORMS EACH DAY...MAINLY IN
THE AFTERNOON AND EVENING...OTHERWISE VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1:30 PM TUESDAY...SOUTHWEST FLOW AROUND BERMUDA HIGH WILL
CONTINUE THROUGH TONIGHT. WINDS ENHANCED BY THE SEA BREEZE WERE
GUSTING ON SHORE THIS AFTERNOON BUT WILL SUBSIDE THROUGH THIS
EVENING. GRADIENT TIGHTENS SLIGHTLY OVERNIGHT LEADING UP TO SW
WINDS TO 15 KTS. THIS WILL BUILD SEAS UP FROM 2 FT TO 2 TO 4 FT BY
MORNING. SEAS OF WILL BE COMPOSED OF S WAVES AROUND 2 FT AT 5
SECONDS AND SE WAVES ABOUT 1 FOOT EVERY 10 SECONDS.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 2:30 PM TUESDAY...MORE OF THE SAME FOR THE SHORT TERM. THE
COMBINATION OF A TROUGH OF LOW PRESSURE INLAND AND HIGH PRESSURE
OFFSHORE WILL KEEP UP A SOUTHWESTERLY FLOW IN THE 10 TO 15 KT RANGE
FOR MUCH OF WEDNESDAY AND THURSDAY. A TIGHTENING GRADIENT DURING THE
AFTERNOON AND EVENING OF BOTH DAYS WILL KICK WINDS UP INTO THE 15 TO
20 KT RANGE. SEAS WILL RANGE FROM 2 TO 4 FT DURING THE TIMES OF
SLACKEST WINDS TO 3 TO 5 FT WITH THE HIGHER WINDS. THUNDERSTORMS
REMAIN A POSSIBILITY OVER THE WATERS...ESPECIALLY LATE EACH
AFTERNOON AND INTO THE EVENINGS.
LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 2:30 PM TUESDAY...TYPICAL SUMMERTIME PATTERN WILL PERSIST
THROUGH THE PERIOD AS BERMUDA HIGH PRESSURE SITS OFFSHORE AND AN
ACTIVE PIEDMONT TROUGH DEVELOPS EACH DAY. THIS CREATES SW WINDS...OF
10-15 KTS FRI/SAT...INCREASING TO 15-20 KTS SUNDAY AS GRADIENT
BECOMES MORE PINCHED DUE TO A STRONGER PIEDMONT TROUGH. SEAS WILL BE
FAIRLY UNIFORM FRI/SAT WITH A COMBINATION OF A 2FT/9SEC SE SWELL AND
4FT/5SEC SW WIND WAVE CREATING 3-4 FT SEAS. SEAS BUILD SLIGHTLY
SUNDAY DUE TO THE STRONGER WINDS...BECOMING 3-5 FT...WITH STEEPER
OVERALL FACES SINCE THE WIND WAVE WILL BECOME MORE PROMINENT IN THE
WAVE SPECTRUM.
&&
.TIDES/COASTAL FLOODING...
AS OF 3:00 AM TUESDAY...THE FULL MOON TODAY WILL MAINTAIN ELEVATED
WATER LEVELS THROUGH MID WEEK AND COULD REACH MINOR COASTAL FLOOD
THRESHOLDS MAINLY IN DOWNTOWN WILMINGTON. DURING THE NEXT FEW
DAYS...THE HIGHEST HIGH TIDE WILL OCCUR BETWEEN 9 PM AND 1 AM IN
DOWNTOWN WILMINGTON OCCURRING ABOUT AN HOUR LATER WITH EACH PASSING
DAY. PEOPLE GATHERING FOR THE FIRE-WORKS WEDNESDAY EVENING IN
DOWNTOWN WILMINGTON MAY OBSERVE OR EXPERIENCE MINOR FLOODING ALONG
PORTIONS OF WATER STREET AND BATTLESHIP ROAD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...RGZ
SHORT TERM...REK
LONG TERM...JDW
AVIATION...DL
MARINE...REK/JDW/RGZ
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
204 PM EDT TUE JUL 3 2012
.SYNOPSIS...
HIGH PRESSURE ALOFT OVER THE REGION WILL WEAKEN THROUGH MID WEEK. AT
THE SURFACE...BERMUDA HIGH PRESSURE AND THE PIEDMONT TROF WILL
AFFECT THE REGION THROUGHOUT THE FORECAST PERIOD. DAYTIME
TEMPERATURES ARE EXPECTED TO DROP TO SLIGHTLY ABOVE NORMAL VALUES
FOR EARLY JULY...WITH HUMID CONDITIONS CONTINUING TO PREVAIL. THE
PIEDMONT TROUGH AND THE SEA BREEZE WILL PROVIDE THE TRIGGER FOR
ISOLATED TO SCATTERED THUNDERSTORMS TO DEVELOP EACH AFTERNOON AND
EVENING THROUGH THE FORECAST PERIOD.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 130 PM TUESDAY...CU DEVELOPMENT HAS BEEN QUITE MEAGER CLOSER
TO THE COAST BUT CU AND CONVECTION FLARING FURTHER INLAND ALONG
PIEDMONT TROUGH. HRRR SHOWS BEST CHC OF CONVECTION OVER OUR LOCAL
AREA WOULD BE IN THE GEORGETOWN WILLIAMSBURG AREA ALONG SEA BREEZE
BOUNDARY. OVERALL EXPECT ISOLATED COVERAGE. THE STEERING FLOW
REMAINS VERY WEAK OUT OF THE N-NW AND THEREFORE EXPECT ANY STORMS
MOVE SLOWLY TOWARD THE COAST WITH BEST CHC OVER WESTERN COUNTIES
THROUGH THIS EVENING.
LIGHT SOUTHWEST FLOW WILL CONTINUE THROUGH TONIGHT BETWEEN BERMUDA
HIGH AND PIEDMONT TROUGH INLAND. GUSTY WINDS ALONG THE COAST
ASSOCIATED WITH AFTERNOON SEA BREEZE WILL TAPER OFF SHORTLY AFTER
SUNSET ALLOWING FOR NEAR CALM WINDS ACROSS THE AREA. ANY CU BUILD
UP THIS AFTERNOON OR ISOLATED CONVECTION WILL ALSO COME TO AN END
LATE THIS EVENING. DRIER AIR AND SUBSIDENCE WILL CONTINUE ALOFT
AS MID TO UPPER RIDGE HOLDS ON THROUGH THE NIGHT.
TEMPS UP BETWEEN 90 AND 95 MOST PLACES THIS AFTERNOON WILL FALL
INTO THE 70S BY MORNING.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 330 AM TUESDAY...AT THE START OF THIS PERIOD...MODELS IN
GENERAL AGREEMENT WITH THE UPPER RIDGING...ACROSS THE FA DURING
ROUGHLY THE PAST 5 DAYS...HAVING RETROGRADED AND MESHED WITH THE
MAIN UPPER RIDGE ACROSS THE CENTRAL U.S. THE UPPER TROF ACROSS THE
NE STATES WILL EXPAND SOUTHWARD AND AFFECT THE FORECAST AREA THROUGH
THURSDAY NIGHT. THE MAIN UPPER TROF AXIS WILL REMAIN OFF THE EAST
COAST...THUS PROVIDING MAINLY A W TO NW FLOW ALOFT. THIS FLOW
THROUGH 7H MAY BECOME STRONG ENOUGH TO KEEP THE SEA BREEZE FROM
PUSHING WELL INLAND...ESPECIALLY DURING THURSDAY. MODELS DO INDICATE
A 5H S/W TROF DROPPING SOUTHEAST AND REACHING AND AFFECTING THE FA
DURING THURSDAY. THE DYNAMICS ASSOCIATED WITH IT AS WELL AS THE
AVAILABLE SFC FEATURES...PIEDMONT TROF AND SEA BREEZE...WILL PROVIDE
THE FORCING NEEDED FOR SCATTERED CONVECTION. WILL ADJUST THURSDAY
POPS TO AS HIGH AS 40 PERCENT...WHICH IS BASICALLY HIGHER THAN CLIMO.
FOR WEDNESDAY POPS...HAVE GONE WITH CLIMO OR LOWER.
HAVE LEANED TOWARD THE SLIGHTLY HIGHER...BY 1 TO 3 DEGREES...NAM MOS
GUIDANCE THIS SHORT TERM. THINKING IS THE NW FLOW ALOFT...A
DOWNSLOPE TRAJECTORY OFF THE MOUNTAINS...WILL OFFSET THE COOLER
READINGS RESULTING FROM THE UPPER TROF AFFECTING THE FA.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 330 AM TUESDAY...MODELS IN GENERAL AGREEMENT WITH THE S/W
UPPER TROF DROPPING SOUTH OF THE FA VERY EARLY IN THE PERIOD. THE
GFS IS MUCH FURTHER SOUTH THAN THE EUROPEAN...AND IS THE PREFERRED
LONG TERM MODEL. SUBSIDENCE ALOFT WILL AFFECT THE FA IN THE WAKE OF
THE DEPARTING UPPER S/W BY MIDDAY FRIDAY THROUGH SATURDAY.
FOR SUN AND MON...THE LONG TERM PATTERN CONTINUES TO EVOLVE WITH THE
EXPANSION OF THE UPPER TROF...WHICH IS PROGGED TO AFFECT THE EASTERN
2/3RDS OF THE U.S. BY EARLY NEXT WEEK. THIS WILL RESEMBLE A WINTER
TYPE UPPER LEVEL PATTERN. WILL INDICATE AT LEAST CLIMO POPS FOR
SUNDAY...HIER ON MONDAY DUE TO FORCING FROM POSSIBLE S/W TROFS ALOFT
PUSHING ACROSS THE FA...AND AIDING THE EXPANDING UPPER TROF.
WILL INDICATE SLIGHTLY HIER THAN CLIMO FOR TEMPERATURES THROUGHOUT THE
LONG TERM...ESPECIALLY WITH DECENT NW FLOW ALOFT DURING THE UPCOMING
WEEKEND.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 18Z...GOOD CAPE...BUT STRONG CONVECTIVE INHIBITION. LOOK FOR
LIGHT SOUTHWESTERLY FLOW TO SHIFT TO THE SOUTH ALONG THE COAST WITH
THE RESULTANT. AIR MASS SHOULD HAVE ENOUGH CAPE TO KICK OFF A STORM
OR TWO BY LATE AFTERNOON...BOTH ALONG THE SEA BREEZE BOUNDARY AND
INLAND. COVERAGE IS EXPECTED TO BE QUITE MINIMAL AT THIS TIME.
OVERNIGHT...LIGHT SOUTHWESTERLY FLOW WITH POSSIBLE MVFR HAZE/FOG
AFTER 08Z. WEDNESDAY...THERMAL TROUGH WILL CONTINUE TO GIVE US
SOUTHWESTERLY FLOW...PERHAPS A BIT STRONGER THAN TODAY. ISOLATED
CONVECTION EXPECTED BY THE END OF THE FORECAST PERIOD.
EXTENDED OUTLOOK...A CHANCE OF THUNDERSTORMS EACH DAY...MAINLY IN
THE AFTERNOON AND EVENING...OTHERWISE VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 130 PM TUESDAY...SOUTHWEST FLOW AROUND BERMUDA HIGH WILL
CONTINUE THROUGH TONIGHT. WINDS ENHANCED BY THE SEA BREEZE WERE
GUSTING ON SHORE THIS AFTERNOON BUT WILL SUBSIDE THROUGH THIS
EVENING. GRADIENT TIGHTENS SLIGHTLY OVERNIGHT LEADING UP TO SW
WINDS TO 15 KTS. THIS WILL BUILD SEAS UP FROM 2 FT TO 2 TO 4 FT BY
MORNING. SEAS OF WILL BE COMPOSED OF S WAVES AROUND 2 FT AT 5
SECONDS AND SE WAVES ABOUT 1 FOOT EVERY 10 SECONDS.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT /...
AS OF 330 AM TUESDAY...A TIGHTENING SFC PG WILL DEVELOP ACROSS THE
WATERS LATE WEDNESDAY THROUGH THURSDAY. SFC RIDGING FROM THE CENTER
OF THE BERMUDA HIGH WILL EXTEND WESTWARD ACROSS FLORIDA INTO THE
GULF...AND AT THE SAME TIME THE PIEDMONT TROF WILL PERSIST ACROSS
THE CENTRAL CAROLINAS. THE 2 FEATURES COMBINED WILL YIELD A SW WIND
10-15 KT INITIALLY...INCREASING TO 15-20 KT BY THURSDAY AND
CONTINUING THROUGH THURSDAY NIGHT. THE PASSAGE OF AN UPPER S/W TROF
WILL PROVIDE THE TIGHTENING SFC PG. SIG SEAS WILL INCREASE FROM
AROUND 3 FT...TO 3 TO 5 FT ON THURSDAY...WITH 6 FOOTERS POSSIBLE OFF
CAPE FEAR. IN ADDITION TO THE WIND DRIVEN SHORT PERIOD WAVES...A 1.5
TO 2.5 FT...BETTER THAN CLIMO...ESE GROUND SWELL AT 10 SECOND
PERIODS WILL AFFECT THE LOCAL WATERS.
LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 330 AM TUESDAY...AFTER THE PASSAGE OF THE UPPER S/W TROF TO
THE SOUTH EARLY FRIDAY...THE SFC PRESSURE PATTERN WILL REMAIN NEARLY
LIKE WHAT WAS EXPERIENCED DURING THE SHORT TERM...WITH THE EXCEPTION
OF THE SFC PG WHICH WILL LOOSEN CONSIDERABLY DURING FRIDAY AND
LIKELY EXTEND INTO SATURDAY. THIS WILL PRODUCE SW WINDS DIMINISHING
TO 10-15 KT. SIG SEAS WILL FOLLOW SUIT AS THE WIND DRIVEN WAVE
PORTION SUBSIDES. THE 9-10 SECOND PERIOD ESE GROUND SWELL WILL
REMAIN IN THAT 1.5 TO 2.5 FT RANGE.
&&
.TIDES/COASTAL FLOODING...
AS OF 300 AM TUESDAY...THE FULL MOON TODAY WILL MAINTAIN ELEVATED
WATER LEVELS THROUGH MID WEEK AND COULD REACH MINOR COASTAL FLOOD
THRESHOLDS MAINLY IN DOWNTOWN WILMINGTON. DURING THE NEXT FEW
DAYS...THE HIGHEST HIGH TIDE WILL OCCUR BETWEEN 9 PM AND 1 AM IN
DOWNTOWN WILMINGTON OCCURRING ABOUT AN HOUR LATER WITH EACH PASSING
DAY. PEOPLE GATHERING FOR THE FIRE-WORKS WEDNESDAY EVENING IN
DOWNTOWN WILMINGTON MAY OBSERVE OR EXPERIENCE MINOR FLOODING ALONG
PORTIONS OF WATER STREET AND BATTLESHIP ROAD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...RGZ
SHORT TERM...DCH
LONG TERM...DCH
AVIATION...DL
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1035 AM EDT TUE JUL 3 2012
.SYNOPSIS...
AFTERNOON TEMPERATURES WILL CONTINUE TO BE WELL ABOVE NORMAL DUE TO
AN UPPER LEVEL HIGH PRESSURE SYSTEM EXTENDING INTO THE CAROLINAS
FROM THE WEST. OCCASIONAL UPPER LEVEL DISTURBANCES WILL
MOVE THROUGH THE REGION FROM THE NORTHWEST.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1035 AM TUESDAY...
A BROAD UPPER LEVEL HIGH PRESSURE SYSTEM ANCHORED OVER THE LOWER MS
VALLEY CONTINUES TO INFLUENCE THE SENSIBLE WEATHER OVER CENTRAL NC
THIS MORNING. A MINOR S/W IN THE WESTERLIES OVER THE GREAT LAKES
WILL ATTEMPT TO LOWER HEIGHTS A BIT IN OUR REGION LATE TODAY AND
MORE SO ON WEDNESDAY. 12Z UPPER AIR ANALYSIS DEPICTS MOISTURE
ADVECTION AT 850MB WITH GSO REPORT A DEWPOINT OF 9 DEG WHILE RNK
MEASURED 13. 850MB TRAJECTORIES FAVOR BEST MOISTURE ADVECTION IN THE
WESTERN PIEDMONT VERSUS THE REMAINDER OF CENTRAL NC. DIFFICULT TO
PINPOINT A FEATURE THAT WILL INITIATE CONVECTION THOUGH LINGERING
SURFACE TROUGH SW-NE ACROSS CENTRAL NC MAY SERVE AS A FEATURE FOR
SURFACE MOISTURE TO POOL ALONG...AIDING TO TRIGGER/SUSTAIN
CONVECTION. FINALLY....LATEST HRRR MODEL ALONG WITH 09Z RUC AND
OTHER CONVECTION ALLOWING MODELS FAVOR DEVELOPMENT IN THE SW
PIEDMONT. DUE TO LACK OF EVIDENCE ALOFT...WILL ONLY RAISE POPS TO
SMALL CHANCE IN THIS REGION WITH CONTINUED SLIGHT CHANCE OVER THE
REMAINDER OF THE CWA.
CONVECTIVE PARAMETERS STILL SUGGEST A THREAT FOR ISOLATED SEVERE
WITH THE MAIN THREAT LOCALLY DAMAGING WINDS. ALSO...PER MODEL
SOUNDINGS...ENOUGH INSTABILITY RESIDES ALOFT TO CAUSE STORMS TO
PRODUCE AN EXCESSIVE AMOUNT OF LIGHTNING...ESPECIALLY STORMS THAT
OCCUR ALONG AND EAST OF HIGHWAY 1.
LITTLE CHANGE TO TEMPS REQUIRED AT THIS TIME. OBSERVED LOW LEVEL
THICKNESSES CLOSE TO NUMBERS PREDICTED BY MODEL GUIDANCE. AFTERNOON
TEMPS IN THE MID-UPPER 90S COMBINED WITH THE DEWPOINT COMPUTES TO
HEAT INDICES 100-104. WILL CONTINUE TO MONITOR TRENDS THOUGH ANY
PLACE THAT EXPERIENCE 105 DEGREES OR GREATER MAY ONLY SEE THESE
CONDITIONS FOR TWO HOURS OR LESS. -WSS
THE GFS SEEMS OVERDONE IN GENERATING VORTICES AND SUSTAINING
CONVECTION OVERNIGHT. ANY AFTERNOON CONVECTION SHOULD BECOME
ISOLATED TO ABSENT BY LATE EVENING. LOW TEMPERATURES IN THE LOW TO
MID 70S.
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 315 AM...
AS UPPER LEVEL RIDGING BUILDS OVER THE MIDWEST... STRETCHING FROM
NEW ENGLAND INTO TENNESSEE WEDNESDAY MORNING WILL MAKE SLOW PROGRESS
TOWARD CENTRAL NORTH CAROLINA. THERE IS BETTER THAN AVERAGE
CONSENSUS THAT THE WAVE WILL SHARPEN OVER VIRGINIA AND WESTERN NORTH
CAROLINA BY LATE AFTERNOON WEDNESDAY. SOMEWHAT WEAK MID LEVEL FLOW
SHIFTS TO WEST DURING THE AFTERNOON... WITH ATLANTIC AND GULF
MOISTURE LARGELY UNAVAILABLE. THUS WILL HOLD WEDNESDAY AFTERNOON
RAIN CHANCES TO NO MORE THAN 40 PERCENT NORTHWEST... TAPERING TOWARD
SLIGHT CHANCES IN THE SOUTHEAST. RAIN CHANCES SHIFT EAST OVERNIGHT
AS THE WEAK MID LEVEL TROUGH PUSHES EAST... WITH SHOWERS PERHAPS NOT
CLEARING THE EASTERN PIEDMONT UNTIL JUST BEFORE DAWN THURSDAY.
SLIGHT CHANCES FOR SEVERE THUNDERSTORMS AS POTENTIAL ENERGY AND
INSTABILITY CONTINUE WITH LIFTED INDICES AROUND MINUS FIVE AND CAPE
LIKELY IN EXCESS OF 2000 J/KG.
LOW LEVEL THICKNESSES FALL IN ADVANCE OF THE SHORT WAVE WEDNESDAY
AND CLOUDS WILL INTERFERE WITH INSOLATION. HOWEVER THICKNESSES AND
TEMPERATURES SHOULD STILL BE ABOVE NORMAL... NEAR 93 NORTHWEST TO
AROUND 97 SOUTHEAST. LOW TEMPERATURES 70 TO 74.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 310 AM TUESDAY...
PROBABLE PATTERN CHANGE TOWARD WETTER AND LESS HOT CONDITIONS
ACROSS CENTRAL NC BY EARLY NEXT WEEK...
MID LEVEL TROUGHING WILL DRIFT SOUTHWESTWARD ACROSS CENTRAL AND
ESPECIALLY SOUTHERN NC THU...AROUND ANOTHER BUILDING MID-UPPER RIDGE
OVER THE UPPER MIDWEST. THIS RIDGE WILL THEN BRIEFLY EXPAND EASTWARD
ACROSS THE CAROLINAS FRI-SAT...BEFORE RETROGRADING WESTWARD IN
RESPONSE TO THE DEVELOPMENT OF A NEGATIVE NAO AND POSITIVE
PNA-DRIVEN TROUGH ALOFT OVER THE NORTHEASTERN QUARTER OF THE
NATION/SE CANADA SUNDAY THROUGH EARLY NEXT WEEK. THE
PRESENCE/PROXIMITY OF THE MID LEVEL TROUGH SUGGESTS SCATTERED
PULSE CONVECTION WILL FIRE OVER CENTRAL NC THU...FOCUSED OVER THE
SANDHILLS AND SOUTHERN PIEDMONT... FOLLOWED BY DIMINISHING
PROBABILITIES AS THE MID-UPPER RIDGE EXPANDS EASTWARD FRI-SAT. IT
THEN APPEARS THAT THE ESTABLISHMENT OF THE AFOREMENTIONED TROUGH
ALOFT ACROSS THE NORTHEAST WILL FORCE A CONVECTION-FOCUSING FRONTAL
ZONE SOUTH INTO NC SUNDAY THROUGH EARLY NEXT WEEK. THE ARRIVAL OF
THE FRONTAL ZONE WILL ALSO COOL PRECEDING MIDDLE TO UPPER 90S HEAT
TO AT OR BELOW NORMAL VALUES BY THE END OF THE PERIOD.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
AS OF 745 AM...
A WEAK SURFACE TROUGH WILL LINGER OVER THE AREA INTO WEDNESDAY
MORNING. LOCAL VISIBILITIES NEAR 5 MILES IN FOG OR HAZE UNTIL
JUST AFTER SUNRISE...BUT MOST WILL BE VFR. A SLIGHT CHANCE FOR A
THUNDERSTORM MID AFTERNOON INTO THE EVENING.
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS ARE POSSIBLE
WEDNESDAY AFTERNOON AND EVENING. THEREAFTER...AS UPPER LEVEL HIGH
PRESSURE BUILDS NORTH...THE CHANCES FOR SHOWERS AND THUNDERSTORMS
WILL DIMINISH. LATE NIGHT AND EARLY MORNING FOG OR HAZE...MAINLY
MVFR...COULD OCCUR AS THE AIR MASS CHANGES LITTLE FOR MUCH OF THIS
PERIOD.
&&
.CLIMATE...
DAILY RECORD HIGHS AND YEAR THE RECORD WAS LAST SET:
JULY 3 (TUESDAY)
RDU: 98 (1955)
GSO: 98 (1911)
FAY: 100 (1954)
ALL TIME RECORD HIGHS:
RDU: 105 DEGREES (6/30/2012, 6/29/2012, 8/21/2007, 8/18/1988,
7/23/1952)
GSO: 104 DEGREES (7/27/1914, 6/12/1914, 6/12/1912)
FAY: 107 DEGREES (8/9/2007, 7/22/1932)
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...99
NEAR TERM...WSS/99
SHORT TERM...99
LONG TERM...WSS
AVIATION...99
AREA FORECAST DISCUSSION
NWS BISMARCK ND
323 AM CDT TUE JUL 3 2012
.SHORT TERM...TODAY THROUGH WEDNESDAY...
FORECAST HIGHLIGHTS TODAY ARE THE RED FLAG WARNING IN THE FAR
SOUTHWEST AND POSSIBLE SEVERE THUNDERSTORMS LATER TODAY INTO
TONIGHT.
LATEST WATER VAPOR IMAGERY REVEALS SOUTHWEST FLOW INTO NORTH
DAKOTA AROUND HIGH PRESSURE CENTERED OVER THE OK/TX PANHANDLE. A
SHORTWAVE OVER SOUTHEAST MONTANA WAS GENERATING AN AREA OF
SHOWERS AND THUNDERSTORMS ACROSS SOUTHEAST MONTANA AND NORTHEAST
WYOMING. THIS AREA WAS JUST NOW BEGINNING TO PUSH INTO OUR
SOUTHWEST ZONES. THE HRRR HAD THIS AREA PEGGED FROM SEVERAL HOURS
AGO AND WILL CONTINUE TO FOLLOW IT THROUGH THE MORNING FOR MAKING
GRIDS. OVERALL SCATTERED SHOWERS AND THUNDERSTORMS IN THE
SOUTHWEST EARLY THIS MORNING WILL STRETCH THEIR WAY NORTHEAST INTO
THE BISMARCK/MINOT VICINITY BY MID MORNING...BUT SHOULD WEAKEN
OUT AS THE MAIN SHORTWAVE ALSO WEAKENS AND BECOMES MORE ILL
DEFINED. THE MAIN THREAT FOR SEVERE WEATHER WILL BECOME MORE INTO
FOCUS THIS EVENING INTO EARLY TONIGHT ACROSS WESTERN AND MOST OF
CENTRAL NORTH DAKOTA. A COLD FRONT WILL BE POSITIONED FROM WESTERN
SASKATCHEWAN INTO EASTERN MONTANA BY 00Z WEDNESDAY. LOW LEVEL H85
SOUTHERLY WINDS ARE FORECAST TO BRIEFLY INCREASE FROM 00Z TO 06Z
HELPING TO ADVECT MOISTURE ALONG AND AHEAD OF THE FRONT.
INSTABILITY APPEARS STRONGEST EARLY TONIGHT THEN WEAKENING AFTER
MIDNIGHT. THE BEST UPPER LEVEL DIVERGENCE REMAINS IN NORTHWEST TO
NORTH CENTRAL NORTH DAKOTA OVERNIGHT AND CONSEQUENTLY THIS IS
WHERE THE HIGHEST POPS/QPF IS FORECAST TO OCCUR. THE MAIN THREATS
WILL BE LARGE HAIL AND DAMAGING WINDS. THE COLD FRONT WILL
PROGRESS TO A MINOT/BISMARCK LINE BY 12Z WEDS...THEN INTO THE
JAMES RIVER VALLEY WEDNESDAY AFTERNOON. THE THREAT OF SEVERE
WEATHER LOOKS TO SHIFT FAR ENOUGH EAST WEDNESDAY WHEREBY THE JAMES
RIVER VALLEY WOULD BE REMOVED FROM ANY SUCH THREAT AT THIS TIME. DRIER
AIR AND A BIT COOLER TEMPERATURES WEDNESDAY ACROSS WESTERN AND
CENTRAL NORTH DAKOTA WITH PLENTY OF SUNSHINE DEVELOPING FROM WEST
TO EAST.
.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...
A COLD FRONT WILL EXIT THE REGION TO THE EAST WEDNESDAY NIGHT
FOLLOWED BY HIGH PRESSURE AND A BRIEF BREAK IN RAIN CHANCES. FOR
THURSDAY THROUGH SATURDAY...A SERIES OF SHORT WAVE TROUGHS ARE
EXPECTED TO MOVE THROUGH THE UPPER RIDGE AND SUPPORT SHOWERS AND
THUNDERSTORMS AT TIMES...MAINLY OVER THE SOUTHERN THIRD OF THE
FORECAST AREA. BY LATE IN THE PERIOD...MODEL CONSENSUS INDICATES
THE UPPER RIDGE WILL TRANSLATE INTO THE WESTERN CONUS...WITH
NORTHWEST FLOW ALOFT ACROSS NORTH DAKOTA. AS A RESULT...HOT
CONDITIONS SHOULD REMAIN CONFINED TO THE WEST OF THE
DAKOTAS...WITH SEASONABLY WARM TEMPERATURES MAINLY IN THE 80S OVER
THE FORECAST AREA.
&&
.AVIATION...03/06Z ISSUANCE...
EXPECT VFR CONDITIONS THROUGH MUCH OF THE TAF PERIOD. WILL
CONTINUE TO MONITOR PROGRESS OF CONVECTION IN SOUTHWEST ND FOR
POTENTIAL IMPACTS ON KDIK. LATER TONIGHT...A COLD FRONT WILL PUSH
INTO WESTERN NORTH DAKOTA WITH INCREASING CHANCES FOR THUNDERSTORMS.
&&
.FIRE WEATHER...
AFTERNOON HIGHS ACROSS SLOPE AND BOWMAN COUNTIES TUESDAY
AFTERNOON WILL CLIMB INTO THE MID 90S. VERY HIGH GRASSLAND FIRE
DANGER INDICES IN COMBINATION WITH MINIMUM RELATIVE HUMIDITY OF
AROUND 25 PERCENT AND SOUTH WINDS OF 20 TO 30 MPH WILL CREATE
CREATE CRITICAL WILDFIRE BEHAVIOR. A RED FLAG WARNING CONTINUES
FOR FAR SOUTHWEST NORTH DAKOTA...WHICH INCLUDES SLOPE AND BOWMAN
COUNTIES TUESDAY AFTERNOON AND EVENING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 11 AM THIS MORNING TO 8 PM MDT THIS
EVENING FOR NDZ040-043.
&&
$$
SHORT TERM...KS
LONG TERM/AVIATION...RK
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1147 PM CDT MON JUL 2 2012
.DISCUSSION...LATEST WATER VAPOR IMAGERY SHOWS A SOUTHWEST FLOW
INTO NORTH DAKOTA WITH A SHORTWAVE ROTATING THROUGH WYOMING. AN
AREA OF SHOWERS AND ISOLATED THUNDERSTORMS PER REGIONAL RADAR LOOP
WERE OCCURRING OVER NORTHEAST WYOMING AND FAR SOUTHEAST MONTANA.
00Z MODELS NOT CAPTURING THIS AREA WELL...HOWEVER THE LAST TWO
HOURLY HRRR RUNS HAVE...AND CONTINUE TO DEVELOP THIS AREA
OVERNIGHT INTO OUR SOUTHWEST ZONES. HAVE NUDGED POPS INTO THE CHC
CATEGORY MAINLY BETWEEN 09Z AND 12Z AND EXPANDED THE SLIGHT CHC
FURTHER NORTH AND EAST BASED ON THE HRRRS COVERAGE. TEMPERATURE
AND DEW POINTS ALREADY REACHING SATURATION OVER CENTRAL NORTH
DAKOTA WITH PATCHY FOG THE RESULT. EXPECTING AREAS OF FOG AFTER
06Z FOR MUCH OF CENTRAL NORTH DAKOTA AND THIS IS REFLECTED IN THE
GRIDS. REST OF FORECAST REMAINS ON TRACK.
&&
.AVIATION...VFR CONDITIONS ARE EXPECTED ACROSS WESTERN AND CENTRAL NORTH
DAKOTA TONIGHT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 11 AM TO 8 PM MDT TUESDAY FOR NDZ040-043.
&&
$$
DISCUSSION...KS
AVIATION...NH
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
940 PM EDT WED JUL 4 2012
.SYNOPSIS...
UPPER LEVEL HIGH PRESSURE WILL EXPAND ACROSS THE REGION THROUGH
THE REST OF THE WEEK KEEPING HOT CONDITIONS IN PLACE. THE HEAT
WAVE WILL BREAK EARLY NEXT WEEK AFTER A COLD FRONT MOVES THROUGH
DURING THE WEEKEND...ALLOWING COOLER HIGH PRESSURE TO BUILD IN.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
STORMS OVER NORTHERN OHIO HAVE BEEN SLOWLY MOVING SOUTH SOUTHEAST
AND HAVE MADE IT INTO THE NORTHERN PART OF THE FORECAST AREA. THEY
SHOULD CONTINUE THEIR SLOW TREK TOWARDS CENTRAL OHIO LATE THIS
EVENING BUT BEGIN TO GRADUALLY DIMINISH AS THE BOUNDARY LAYER
COOLS. LATEST HRRR AND 18Z NAM SUPPORT THIS WEAKENING SCENARIO.
ELSEWHERE CANNOT RULE OUT AN ADDITIONAL ISOLATED STORM IN THE TRI-
STATE THROUGH THE REST OF THE EVENING. ALL PRECIPITATION WILL
DISSIPATE LATER TONIGHT. HAVE LEANED TOWARDS WARMER GUIDANCE FOR
LOWS.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
ANOTHER DISTURBANCE COMING OVER THE TOP OF AN EXPANDING RIDGE WILL
MOVE SOUTHEAST ACROSS THE UPPER OHIO VALLEY TOMORROW. THIS WILL
BRING ANOTHER CHANCE OF SHOWERS AND THUNDERSTORMS PRIMARILY FOR
THE EASTERN ZONES DURING THE AFTERNOON AND EVENING. DO NOT EXPECT
STORMS TO BE EXPANSIVE ENOUGH TO HAVE ANY MORE THAN A TEMPORARY
EFFECT ON TEMPERATURES.
GUIDANCE SUGGESTS THAT READINGS WILL BE SLIGHTLY WARMER THAN
TODAYS HIGHS. WITH LITTLE VARIATION IN DEW POINTS...THESE HIGHER
TEMPERATURES SHOULD PUSH MOST LOCATIONS INTO HEAT WARNING
CRITERION /HEAT INDEX 105 OR GREATER/. IN ADDITION THIS WILL BE A
PROLONGED PERIOD OF HIGH HEAT INDICES. SO EVEN IF SOME PLACES DO
NOT MEET THE THRESHOLD...THE CUMULATIVE EFFECTS OF THE HEAT WILL
TAKE A TOLL. THUS THE EXCESSIVE HEAT WARNING WAS EXPANDED TO ALL
COUNTIES THROUGH SATURDAY. CONTINUED TO FAVOR WARMER MOS FOR
LOWS.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
HOT AND HUMID CONDITIONS WILL START OUT THE LONG TERM TIME FRAME
AND WILL CONTINUE ACROSS THE FA INTO SATURDAY. TEMPERATURES ON
FRIDAY AND SATURDAY WILL BE IN THE UPPER 90S TO AROUND 100 WITH
HEAT INDEX VALUES AROUND 105 DEGREES. DUE TO THIS THE ENTIRE AREA
HAS BEEN UPGRADED TO AN EXCESSIVE HEAT WARNING FOR FRIDAY AND
SATURDAY. WITH RIDGE IN PLACE OVER THE AREA THE FA WILL STAY DRY
ON FRIDAY AND DURING MOST OF THE DAY ON SATURDAY. THERE IS SOME
DISCREPANCY BETWEEN THE MODELS ON WHEN PRECIPITATION WILL OCCUR
AFTER THIS POINT. THE GFS IS A LOT QUICKER WITH THE FRONTAL
BOUNDARY AND THE PRECIPITATION AND BEGINS TO BRING PRECIPITATION
INTO THE AREA SATURDAY NIGHT. THE ECMWF IS SLOWER WITH THE
PRECIPITATION AND BRINGS THE BEST CHANCE OF PRECIPITATION INTO THE
AREA SUNDAY NIGHT. WENT CLOSER TO THE ECMWF SOLUTION AND HAVE THE
GREATEST PRECIPITATION CHANCES IN THE FORECAST DURING THE
OVERNIGHT HOURS SUNDAY NIGHT INTO MONDAY MORNING. PRECIPITATION
WILL THEN LINGER ACROSS SOUTHERN PORTIONS OF THE FA MAINLY IN
NORTHERN KENTUCKY MONDAY NIGHT INTO TUESDAY BEFORE COMPLETELY
EXITING THE AREA. AFTER SATURDAY THERE WILL BE A GENERAL DECREASE
IN TEMPERATURES FOR THE REST OF THE LONG TERM TIME FRAME.
TEMPERATURES BY MONDAY AND TUESDAY WILL BE IN THE 80S ACROSS THE
ENTIRE FA.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
TRICKY START TO THE TAF PERIOD. A LARGE AMOUNT OF UNCERTAINTY
EXISTS THROUGH 06Z AS TO WHETHER CONVECTION ACROSS WESTERN LAKE
ERIE WILL PROPAGATE/SURVIVE SOUTHWARD TOWARD OUR TERMINALS BY
LATE THIS EVENING. HELD OFF FOR THE TAF ISSUANCE ON INSERTING ANY
MENTION OF VCTS OR TEMPOS. HOWEVER...IF CONFIDENCE BEGINS TO RISE
WITH REGARDS TO THESE STORMS OR OUTFLOW AFFECTING THE
TERMINALS...THEN AMENDMENTS WILL BE FORTHCOMING. BEYOND
06Z...SKIES WILL GENERALLY BE PARTLY CLOUDY WITH SOME SCATTERED
CIRRUS OVERNIGHT UNDER LIGHT WINDS. ON THURSDAY...NORTHWEST WINDS
WILL GENERALLY REMAIN UNDER 10 KTS WITH SCATTERED CU DEVELOPING.
AFTERNOON THUNDERSTORMS WILL BECOME POSSIBLE ONCE AGAIN.
HOWEVER...CONFIDENCE AT THAT TIME RANGE WITH THIS CONVECTION
REGIME REMAINS TOO LOW FOR ANY MENTION OF THEM IN THE TAFS AT THE
MOMENT.
OUTLOOK...THUNDERSTORMS POSSIBLE SUNDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...EXCESSIVE HEAT WARNING UNTIL 8 PM EDT SATURDAY FOR OHZ026-034-
035-042>046-051>056-060>065-070>074-077>082-088.
KY...EXCESSIVE HEAT WARNING UNTIL 8 PM EDT SATURDAY FOR KYZ089>100.
IN...EXCESSIVE HEAT WARNING UNTIL 8 PM EDT SATURDAY FOR INZ050-058-
059-066-073>075-080.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...NOVAK
AVIATION...LATTO
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
410 PM EDT TUE JUL 3 2012
.SYNOPSIS...
LIGHT WINDS AT THE SURFACE AND BUILDING MID LEVEL RIDGING TO OUR
WEST WILL KEEP THE OHIO VALLEY VERY WARM FOR THE NEXT SEVERAL
DAYS. NORTHWEST FLOW AROUND THE RIDGE WILL CONTINUE TO BRING
INTERMITTENT DISTURBANCES ACROSS THE OHIO VALLEY THROUGHOUT THIS
TIME PERIOD.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
CONVECTION CONTINUES TO PERCOLATE ACROSS THE EASTERN ZONES ALONG
THE TAIL END OF A DISTURBANCE DROPPING SOUTHEAST ACROSS THE
EASTERN OHIO VALLEY. LACK OF CU FIELD WEST OF THE COLUMBUS AREA
WOULD SUGGEST THE BEST CHANCES FOR CONVECTION OVER THE NEXT FEW
HOURS WILL REMAIN CONFINED ALONG AND EAST OF A LINE FROM DELAWARE
TO SCIOTO COUNTIES.
WITH THE LOSS OF DAYTIME HEATING THIS EVENING...AND THE
DISTURBANCE SHIFTING FARTHER SOUTHEAST OF OUR AREA...HAVE REMOVED
POPS BY MIDNIGHT. THE SPC WRF AND HRRR MODELS ARE SUGGESTING A
POTENTIAL MCS DEVELOPING ACROSS THE UPPER MID WEST THIS EVENING
...AND BRINGING ITS WEAKENING REMNANTS INTO OUR NORTHERN ZONES
BEFORE SUNRISE. GIVEN THE UNCERTAINTY OF THIS SCENARIO...HAVE ONLY
FORECAST SLIGHT CHANCE POPS ACROSS THE NORTH FOR THAT TIME FRAME.
USED A BLEND OF ARW/ECMWF FOR OVERNIGHT LOWS TONIGHT WHICH YIELDS
UPPER 60S ACROSS THE EAST TO LOW 70S ACROSS THE WEST.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
THE MID LEVEL RIDGE AMPLIFIES A BIT ON INDEPENDENCE DAY. THIS WILL
RESULT IN A MORE NORTH TO SOUTH COMPONENT TO THE PROPAGATION OF MID
AND UPPER LEVEL ENERGY TRAVELING ALONG THE PERIPHERY OF THE RIDGE
DURING THIS PERIOD. THE POTENTIAL EXISTS OF A DISTURBANCE TO DROP
SOUTH FROM EASTERN MICHIGAN DURING THE AFTERNOON...WHICH WOULD
RESULT IN THUNDERSTORM DEVELOPMENT TOWARD OUR AREA DURING THE LATE
AFTERNOON AND EVENING. THIS SCENARIO IS DEPICTED BY THE 12Z ARW
AND NAM...BUT NOT BY THE NMM. BASED ON HOW WELL THE ARW PERFORMED
24 HORUS OUT FOR THE PAST TWO EVENTS THIS WEEK...HAVE UPPED THE
POPS TO 50 FOR INDEPENDENCE DAY. AVOIDED GOING ANY HIGHER FOR POPS AT
THIS POINT DUE TO THE UNCERTAINTIES IN THE MODELS DURING THESE
MODES OF CONVECTION.
HAVE BACKED OFF ON HIGH TEMPERATURES A BIT FOR TOMORROW GIVEN THE
LOW TO MID 90S SEEN TODAY...AND THE POSSIBILITY OF CONVECTION BY
TOMORROW AFTERNOON. HOWEVER...THESE TEMPERATURES WILL STILL BE IN
THE LOW TO MID 90S AS WELL. THIS WILL COMBINE WITH DEWPOINTS IN
THE UPPER 60S TO PRODUCE HEAT INDICES UP TO 100 ACROSS MUCH OF OUR
AREA DURING THE LATE AFTERNOON. OVERNIGHT LOWS TOMORROW NIGHT WILL
ONLY DIP INTO THE LOW TO MIDDLE 70S. AND...AT THE SAME TIME
SEVERAL COUNTIES STILL HAVE REDUCED HEAT ADVISORY CRITERIA DUE TO
ONGOING POWER OUTAGES FROM SEVERE STORMS THIS PAST WEEKEND. ALL OF
THE ABOVE COMBINED TO JUSTIFY THE ISSUANCE OF A HEAT ADVISORY FOR ALL
COUNTIES EXCEPT MONTGOMERY AND HAMILTON FROM NOON ON INDEPENDENCE
DAY THROUGH THE END OF THE SHORT TERM. AN EXCESSIVE HEAT WARNING
HAS BEEN ISSUED FOR THE SAME TIME PERIOD FOR HAMILTON AND
MONTGOMERY COUNTIES.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
THE OVERALL PATTERN WILL CHANGE ONLY SLIGHTLY THROUGH THE
WEEKEND...AS THE CENTER OF THE HIGH PRESSURE RIDGE MOVES SLIGHTLY
NORTH THROUGH THE MISSISSIPPI VALLEY. THIS WILL PUT THE CWA IN AN
AREA OF WEAK NORTHERLY FLOW ALOFT...BUT WITH THE EDGE OF THE RIDGE
STILL AFFECTING THE CWA...AND A VERY WEAK SURFACE PRESSURE PATTERN.
THURSDAY THROUGH SATURDAY APPEAR TO BE THE HOTTEST DAYS OF THE
FORESEEABLE FUTURE. WITH LOWS ABOVE 70 DEGREES AND A FORECAST
SOLIDLY SUPPORTING HEAT INDICES ABOVE 100 DEGREES FOR EACH OF THESE
THREE DAYS...THE HEAT ADVISORY HAS BEEN EXTENDED THROUGH SATURDAY.
AT THE SAME TIME...IT WOULD BE HARD TO COMPLETELY RULE OUT A SHOWER
OR THUNDERSTORM AT TIMES DURING THIS PERIOD...GIVEN THE EXPECTED
INSTABILITY. HOWEVER...FORCING SIGNALS ARE UNCERTAIN...AND MOST OF
THIS PERIOD HAS BEEN LEFT DRY IN THE GRIDS.
BY SUNDAY...THE ECMWF AND GFS ARE BOTH INDICATING THE BEGINNING OF A
TRANSITION. A BOUNDARY WILL BE SLOWLY MOVING SOUTH THROUGH THE OHIO
VALLEY...AS DRY HIGH PRESSURE ESTABLISHES ITSELF OVER THE GREAT
LAKES. WHILE THE TIMING DIFFERENCES BETWEEN THE MODELS AND THEIR
SUBSEQUENT RUNS DO NOT ALLOW FOR COMPLETE CERTAINTY...IT IS OBVIOUS
THAT THE TREND WILL BE FOR COOLING CONDITIONS IN THE SUNDAY THROUGH
TUESDAY TIME FRAME. CHANCE POPS WILL ALSO BE USED FOR BOTH SUNDAY
AND MONDAY. ONE REMAINING UNCERTAINTY IS IF THE TEMPERATURE FORECAST
FOR SUNDAY WILL BE ENOUGH TO SUPPORT ADDITIONAL HEADLINES...AND THIS
WILL ONLY BE ABLE TO BE REFINED ONCE THE FRONTAL TIMING IS MORE
CERTAIN. IT IS POSSIBLE THAT A NORTH-TO-SOUTH GRADIENT WILL EXIST
ACROSS THE CWA.
&&
.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
VISIBLE SATELLITE IMAGES ARE SHOWING THE CU BECOMING A BIT MORE
DEFINED ACROSS CENTRAL OHIO AND THE LATEST HRRR IS INDICATING
SOME ISOLATED THUNDERSTORMS POPPING UP IN THE COLUMBUS AREA
THROUGH MID AFTERNOON. AS A RESULT...WOULD EXPECT KCMH/KLCK TO HAVE
THE BEST CHANCE AT SEEING ANYTHING...BUT PROBABILITY STILL APPEARS TOO
LOW TO INCLUDE A MENTION IN THEIR TAFS. WILL ALLOW ANY CU TO
DISSIPATE THIS EVENING WITH MAINLY CLEAR SKIES OVERNIGHT. THIS
COULD LEAD TO SOME LOCALIZED MVFR BR TOWARD DAYBREAK. SCATTERED CU
SHOULD THEN REDEVELOP THROUGH LATE WEDNESDAY MORNING/EARLY
AFTERNOON.
OUTLOOK...THUNDERSTORMS POSSIBLE...MAINLY AFTERNOON AND EVENING
HOURS THROUGH THURSDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR OHZ026-034-035-
042>046-051>056-060-062>065-070>074-078>082-088.
HEAT ADVISORY FROM NOON WEDNESDAY TO 8 PM EDT SATURDAY FOR
OHZ026-034-035-042>046-051>056-060-062>065-070>074-
078>082-088.
EXCESSIVE HEAT WARNING UNTIL 8 PM EDT THIS EVENING FOR OHZ061-
077.
EXCESSIVE HEAT WARNING FROM NOON WEDNESDAY TO 8 PM EDT
SATURDAY FOR OHZ061-077.
KY...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR KYZ089>100.
HEAT ADVISORY FROM NOON WEDNESDAY TO 8 PM EDT SATURDAY FOR
KYZ089>100.
IN...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR INZ050-058-059-
066-073>075-080.
HEAT ADVISORY FROM NOON WEDNESDAY TO 8 PM EDT SATURDAY FOR
INZ050-058-059-066-073>075-080.
&&
$$
SYNOPSIS...LATTO
NEAR TERM...LATTO
SHORT TERM...LATTO
LONG TERM...HATZOS
AVIATION...JGL
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
255 PM EDT TUE JUL 3 2012
.SYNOPSIS...
NORTHWEST FLOW ALOFT WILL CONTINUE THROUGH MIDWEEK. UPPER LEVEL
HIGH PRESSURE WILL BUILD INTO THE AREA LATER IN THE WEEK...BEFORE
NORTHWEST FLOW REDEVELOPS FOR SUNDAY AND CONTINUES INTO NEXT WEEK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
UPPER LEVEL HIGH CENTERED OVER THE MID WEST WITH UPPER LEVEL
DISTURBANCES DROPPING SOUTHEAST THRU THE CWA WILL CONTINUE THIS
PERIOD. WITH A HOT AND HUMID AND CONDITIONALLY UNSTABLE ATMOSPHERE
IN PLACE...THE THREAT FOR THUNDERSTORMS PERSIST. THE BEST
OPPORTUNITY FOR STORMS WILL BE DUE TO MESOSCALE INFLUENCES AND
DIURNALLY DRIVEN. SO THE BEST CHANCE OF STORMS WILL BE AFTERNOON AND
EVENING...ALTHOUGH WILL HAVE TO LEAVE SLIGHT CHANCE OVERNIGHT. AS
USUAL IN THIS REGIME...THE HI RES MODELS WERE USED VERY HEAVILY.
THE HRRR HI RES MODEL SEEMS TO HANDLE A COMPLEX DROPPING SOUTHEAST
FROM EASTERN OHIO THIS AFTERNOON PER RADAR TRENDS...SO WILL HAVE
HIGHEST POPS THRU THIS EVENING IN NORTHEASTERN WV.
OTHERWISE...CHANCE FOR DIURNALLY FAVORED TIMES AND SLIGHT CHAN
TONIGHT.
GOING ON THE HIGH END OF GUIDANCE FOR TEMPS...ALTHOUGH ANY TSTM
ACTIVITY WOULD VARY THAT.
&&
SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
MODELS SUGGEST AN ACTIVE 4TH OF JULY FOR SECTIONS OF THE CWA.
ANOTHER MCS IS FORECAST TO DEVELOP AND MOVE SOUTH FROM THE GREAT
LAKES. WILL HAVE TO MONITOR THIS VERY CLOSELY. CONDITIONS ARE
FAVORABLE FOR THIS DEVELOPMENT AS NORTHWEST FLOW PERSISTS. THE EXACT
STRENGTH AND DIRECTION IS IN QUESTION.
THE CHANCE FOR THUNDERSTORMS DECREASE SLIGHTLY BY THURSDAY INTO
FRIDAY. THIS CONTINUES TO BE CONSISTENT WITH PREVIOUS FORECASTS.
WILL MAKE A FEW MINOR ADJUSTMENTS ONLY.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE AS A FRONTAL SYSTEM
SLIDES SOUTH THIS WEEKEND. SURFACE HIGH PRESSURE WILL FOLLOW THIS
SYSTEM. ONCE AGAIN...THE CWA IS IN NORTHWEST FLOW AS AN UPPER LOW IS
NORTHEAST AND A RIDGE OF HIGH PRESSURE IS SOUTHWEST. HAVE FOLLOWED
HPC AND KEPT HOT TEMPS AND CONTINUED THUNDERSTORM CHANCES THROUGH
MUCH OF THIS PERIOD.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
18Z TUESDAY THRU 18Z WEDNESDAY...
UPPER HIGH ANCHORED OVER THE MID WEST WITH NORTHWEST FLOW ALOFT OVER
THE OHIO VALLEY THIS PERIOD. CONDITIONALLY UNSTABLE ATMOSPHERE WILL
LEAD TO SCATTERED MAINLY AFTERNOON TSTMS MOST AREAS. EXCEPTION WILL
BE THE TAIL END OF AN MCS THAT MAY CLIP NORTHEASTERN WV LATER THIS
AFTERNOON AS IT DROPS SOUTHEAST...AFFECTING MAINLY CKB AND EKN.
OTHERWISE...EXCEPT FOR LOCALLY MVFR TO IFR RIVER AND VALLEY FOG 07Z
TO 12Z WED...EXPECT VFR OUTSIDE OF CONVECTION.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z WEDNESDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: MOST ORGANIZED AFTERNOON TSTM DEVELOPMENT
DEPENDS ON MCS DEVELOPMENT. FOG TIMING EVOLUTION AND INTENSITY MAY
VARY TONIGHT.
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 M
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 M M L
PKB CONSISTENCY H H H H H H H H H H H M
CKB CONSISTENCY H H H H H H H H H H H M
AFTER 18Z WEDNESDAY...
NO WIDESPREAD IFR CONDITIONS EXPECTED AT THIS TIME.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR WVZ005>011-
013>020-024>032.
HEAT ADVISORY FROM NOON TO 7 PM EDT WEDNESDAY FOR WVZ005>011-
013>020-024>032.
OH...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR OHZ066-067-075-
076-083>087.
HEAT ADVISORY FROM NOON TO 7 PM EDT WEDNESDAY FOR OHZ066-067-
075-076-083>087.
KY...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR KYZ101>103-105.
HEAT ADVISORY FROM NOON TO 7 PM EDT WEDNESDAY FOR KYZ101>103-
105.
VA...NONE.
&&
$$
SYNOPSIS...JB/JMV
NEAR TERM...JMV
SHORT TERM...JB
LONG TERM...JB
AVIATION...JMV
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
120 PM EDT TUE JUL 3 2012
.SYNOPSIS...
WEAK SOUTHWEST FLOW AT THE SURFACE WILL BE FOUND OVER THE NEXT
FEW DAYS AS HIGH PRESSURE ALOFT BUILDS OVER THE MIDWEST AND OHIO
VALLEY. WEAK DISTURBANCES IN THE NORTHWEST FLOW ALOFT WILL CREATE
SCATTERED THUNDERSTORM ACTIVITY DURING THE LATE DAY AND EVENING
HOURS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPPER LEVEL RIDGE REMAINS IN PLACE ACROSS THE AREA THIS
MORNING...BUT WEAK EMBEDDED SHORT WAVE ENERGY IS PRODUCING A FEW
SHOWERS ACROSS PARTS OF CENTRAL KENTUCKY. MEANWHILE...MORE
ORGANIZED CONVECTION IS DROPPING DOWN ACROSS LAKE ERIE IN NORTHWEST
FLOW ALOFT. THE AIRMASS WILL DESTABILIZE AGAIN THIS AFTERNOON...SO
AN ISOLATED THUNDERSTORM WILL BE POSSIBLE PRETTY MUCH ANYWHERE.
HOWEVER...WOULD THINK POPS MAY BE SOMEWHAT MORE FAVORABLE ACROSS
OUR NORTHEAST AND SOUTHWEST...DUE TO POSSIBLE OUTFLOW INTERACTIONS
FROM ONGOING PCPN JUST OUTSIDE OF OUR AREA. EXPECT HIGH
TEMPERATURES GENERALLY BE IN THE MID 90S. NO CHANGES MADE TO
HEADLINES WITH HEAT INDICES INTO THE UPPER 90S TO AROUND 100
DEGREES POSSIBLE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
INSTABILITY SHOWERS WILL PEAK LATE IN THE DAY AND EARLY EVENING.
THOUGHT THAT THERE WOULD BE A BUILDING CAP...PARTICULARLY ON
THURSDAY AND FRIDAY...BUT DID NOT FEEL THAT I COULD RULE OUT
ISOLATED TO SCATTERED ACTIVITY IN ANY PERIOD. TEMPERATURES WILL
INCREASE A DEGREE OR SO EACH DAY AND ADVISORIES ARE EXPECTED TO
CONTINUE TO BE POSTED.
OVERNIGHT LOWS ARE CONSISTENTLY BEING FORECAST AROUND OR JUST
ABOVE 70 DUE TO THE INCREASING DEWPOINTS. THOUGHT THAT THIS WAS A
LITTLE HIGH...ESPECIALLY IF ANY SHOWERS DEVELOP. EVEN WITH
THIS...DECIDED TO ERR ON THE WARM SIDE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
UPPER RIDGE OVER THE CENTER OF THE COUNTRY WILL SPREAD BACK EAST
INTO THE FORECAST AREA DURING THE LATTER PART OF THE WEEK.
DISTURBANCES SLIDING DOWN THE FRONT SIDE OF THE RIDGE COULD RESULT
IN STORMS ON WEDNESDAY AND THURSDAY. BUT BY FRIDAY THE HIGH MAY CAP
OFF THOSE CHANCES.
THE UPPER HIGH WILL START TO GET SUPPRESSED ACROSS THE AREA OVER THE
WEEKEND AS SHORT WAVES DROP OUT OF CENTRAL CANADA. A FRONT WILL SAG
SOUTH INTO THE REGION ON SATURDAY AND STALL NEAR THE OHIO RIVER FOR
SUNDAY AND MONDAY. THIS COMBINATION OF FEATURES WILL BRING
ADDITIONAL CHANCES OF STORMS FROM SATURDAY INTO MONDAY.
HEAT WILL CONTINUE THROUGH THE REST OF THE WEEK WITH HEAT INDICES
AROUND ADVISORY LEVELS FOR AN EXTENDED PERIOD OF TIME. RELATIVELY
COOLER READINGS WILL OCCUR SUNDAY AND MONDAY AFTER THE FRONT PASSES.
&&
.AVIATION /17Z TUESDAY THROUGH SATURDAY/...
VISIBLE SATELLITE IMAGES ARE SHOWING THE CU BECOMING A BIT MORE
DEFINED ACROSS CENTRAL OHIO AND THE LATEST HRRR IS INDICATING
SOME ISOLATED THUNDERSTORMS POPPING UP IN THE COLUMBUS AREA
THROUGH MID AFTERNOON. AS A RESULT...WOULD EXPECT KCMH/KLCK TO HAVE
THE BEST CHANCE AT SEEING ANYTHING...BUT PROBABILITY STILL APPEARS TOO
LOW TO INCLUDE A MENTION IN THEIR TAFS. WILL ALLOW ANY CU TO
DISSIPATE THIS EVENING WITH MAINLY CLEAR SKIES OVERNIGHT. THIS
COULD LEAD TO SOME LOCALIZED MVFR BR TOWARD DAYBREAK. SCATTERED CU
SHOULD THEN REDEVELOP THROUGH LATE WEDNESDAY MORNING/EARLY
AFTERNOON.
OUTLOOK...THUNDERSTORMS POSSIBLE...MAINLY AFTERNOON AND EVENING
HOURS THROUGH THURSDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR OHZ026-034-035-
042>046-051>056-060-062>065-070>074-078>082-088.
EXCESSIVE HEAT WARNING UNTIL 8 PM EDT THIS EVENING FOR OHZ061-
077.
KY...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR KYZ089>100.
IN...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR INZ050-058-059-
066-073>075-080.
&&
$$
SYNOPSIS...FRANKS
NEAR TERM...JGL
SHORT TERM...FRANKS
LONG TERM...
AVIATION...JGL
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
1155 PM CDT MON JUL 2 2012
.DISCUSSION...
QUIET AND WARM NIGHT AHEAD. LAST FEW RUNS OF THE HRRR REALLY
STRUGGLING AND WANTED CONVECTION TO DEVELOP AROUND CHAMBERLAIN AT
0Z... CAPPING WAS TOO MUCH TO OVERCOME. CONVECTION IN WESTERN
NEBRASKA WILL NEED TO BE WATCHED AS IT COULD LEAK INTO THE FAR
WESTERN CWA LATER TONIGHT...BUT WOULD NOT BE SEVERE IF IT DID.
OTHERWISE...WITH THE STRONGER WINDS THIS EVENING SLOWED THE DIURNAL
DROP A BIT WHICH KEPT FAIRLY TOASTY READINGS IN THROUGH THE EVENING.
THE BOUNDARY TO THE NORTH BARELY SNEAKING INTO THE FAR WESTERN CWA
AT 2Z...SO THE MODELS PROJECTION FOR IT TO LEAK SOUTH ANOTHER 40 OR
50 MILES AT BEST SEEMS REASONABLE. FAIRLY BEEFY DEW POINTS IN
NORTHERN SOUTH DAKOTA SO DEW POINTS COULD CLIMB PRETTY QUICKLY
TOMORROW MORNING WHEREVER THIS BOUNDARY SETS UP IN THE MORNING.
REGARDLESS OF THIS VERY WARM TONIGHT AND HOT AGAIN ON TUESDAY.
WITHOUT THE ADDED MIXING EFFECTS AHEAD OF THE INCOMING FRONT TODAY
SHOULD BE LESS READINGS OVER 100 BUT MORE THAN LIKELY HIGHER DEW
POINTS AND LIGHTER WINDS SO PRETTY UNCOMFORTABLE ON TUESDAY. /08
&&
.AVIATION.../FOR THE 06Z TAF ISSUANCE/
VFR THROUGH 04/06Z. LOW LEVEL FLOW AND MIXING SOUTHEAST OF WEAKENING
AND SLOWING SURFACE TROUGH MOVING INTO AREA SHOULD PREVENT
VISIBILITIES FROM DROPPING BELOW 6SM NEXT SEVERAL HOURS. WEAKENING
WIND FIELDS ON BOTH SIDES OF TROUGH SHOULD KEEP SURFACE GUSTS WELL
BELOW 25 KNOTS THROUGH 04/06Z. ISOLATED HIGH BASED SHRA/TSRA FAR
SOUTHWEST CORNER THROUGH 08Z AND FAR WEST 21Z-04/03Z.
&&
.PREV DISCUSSION...
FRONT APPROACHING FROM THE WEST BUT ATMOSPHERE REMAINS CAPPED.
WITHOUT CONVECTION...FRONT WILL STRUGGLE TO SHIFT EAST AND WILL
GRADUALLY WEAKEN AND STALL ACROSS THE AREA. SHOULD BE ANOTHER MILD
NIGHT ACROSS THE AREA WITH 925 HPA TEMPS REMAINING NEAR 30C. WITH
FRONT STALLING ACROSS THE AREA...IT MIGHT BRING SOME SLIGHT RELIEF
TO THE NORTHERN FRINGE OF THE CWA TOMORROW...WHILE AREAS FURTHER TO
THE SOUTH WILL WARM TO THE UPPER 90S TO NEAR 100.
THE HOT WEATHER WILL CONTINUE THROUGH FRIDAY ACROSS THE CWA AS RIDGE
ALOFT HOLDS STRONG. HIGHS IN THE 90S TO AROUND 100 CAN BE EXPECTED
WEDNESDAY THROUGH FRIDAY. THE ONLY FLY IS SMOKE FROM FIRES TO THE
WEST. IF FAIRLY THICK...THEN HIGHS COULD BE 3 TO 5 DEGREES COOLER.
WILL KEEP HEAT ADVISORY IN PLACE THROUGH FRIDAY. NEXT ISSUE IS
THUNDERSTORMS CHANCES THROUGH FRIDAY. SURFACE FRONT WILL SAG SOUTH
INTO FAR NORTHERN CWA LATER WEDNESDAY NIGHT INTO FRIDAY. SOUTH OF
BOUNDARY WILL REMAIN CAPPED...BUT CAP MAY WEAKEN ENOUGH TO THE NORTH
THAT A FEW STORMS COULD FIRE. MODELS DIFFER ON PLACEMENT OF THIS
FRONT WITH EC FURTHER NORTH AS IT HOLD RIDGE ALOFT WHILE BOTH GFS
AND NAM SLIGHTLY WEAKER. SO WITH UNCERTAINTY ON EXACT STRENGTH OF
RIDGE WILL KEEP SMALL CHANCES OF THUNDERSTORMS IN FORECAST WEDNESDAY
THROUGH FRIDAY...AND MAINLY NOCTURNAL.
THUNDERSTORM CHANCE WILL INCREASE SATURDAY NIGHT THROUGH SUNDAY
NIGHT AS RIDGE ALOFT FLATTENS AND SHIFTS WEST ALLOWING FOR A MORE
NORTHWEST FLOW AND WHICH WILL ALLOW STRONGER WAVES TO DIVE ACROSS
CWA. SEVERE THREAT NOT ALL THAT GREAT...BUT WITH WEAK MID LEVEL
FLOW...SLOW MOVING STORMS COULD PRODUCE HEAVY RAINS...WITH A FEW
POSSIBLY SEVERE. COOLER TEMPERATURES SHOULD ALSO FINALLY SPREAD
SOUTH ACROSS CWA THIS WEEKEND AND PERSIST INTO NEXT WEEK.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
IA...HEAT ADVISORY THROUGH 7 PM CDT FRIDAY FOR IAZ001>003-012>014-
020>022-031-032.
MN...HEAT ADVISORY THROUGH 7 PM CDT FRIDAY FOR MNZ071-072-080-081-
089-090-097-098.
NE...HEAT ADVISORY THROUGH 7 PM CDT FRIDAY FOR NEZ013-014.
SD...HEAT ADVISORY THROUGH 7 PM CDT FRIDAY FOR SDZ038>040-050-
052>071.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
312 PM CDT TUE JUL 3 2012
.DISCUSSION...
LOOKING AT A LOOP OF VIS SATELLITE IMAGERY SHOWS QUITE A BIT OF
CLOUD COVER WHICH HAVE HELD DOWN MAX TEMPS. STILL A FEW AREAS HAVE
REACHED THE LOW 90S AND WITH THE HEATING A FEW ISO STORMS HAVE
DEVELOPED NEAR MOST OF THE HOUSTON AREA. THINK ACTIVITY SHOULD
STAY ISO WITH NOT MUCH INCREASE IN COVERAGE. STORMS SHOULD END
THIS EVENING WITH THE LOSS OF HEATING.
SO WILL WE HAVE THUNDERSTORMS FOR INDEPENDENCE DAY? WELL LATEST
MODEL GUIDANCE AT LEAST SUGGESTS THE POSSIBILITY OF MORE SCT
ACTIVITY TOMORROW AT LEAST WEST AND SOUTH OF HOUSTON METRO. GFS
STILL HIGHLIGHTS THIS AREA FOR CONVECTION. HOWEVER MODEL SOUNDINGS
FROM BOTH THE NAM AND GFS ARE NOT ALL THAT SUPPORTIVE ESPECIALLY
BY THE AFTERNOON. THE UPPER LEVELS LOOK TO BE A LITTLE BETTER
SUPPORTIVE FOR CONVECTION TOMORROW. UPPER RIDGE STILL EXPECTED TO
REMAIN NORTH OF THE AREA IN THE C PLAINS AND AN INVERTED TROUGH
OVER THE C GULF IS EXPECTED TO PUSH INLAND OVERNIGHT INTO TOMORROW
MORNING. THIS SHOULD KEEP SUBSIDENCE AT A MINIMUM AND ALLOW FOR
PULSE CONVECTION. THINK THAT 30 POPS FOR THE AREAS ALONG US 59 SW
OF HOUSTON LOOKS GOOD WITH 20 POPS ELSEWHERE. DO NOT THINK
CONVECTION WILL LAST MUCH PAST THE LATE EVENING SO MOST AREAS
SHOULD BE A MINIMUM DRYING OUT BEFORE ANY FIREWORKS.
LONG TERM FORECAST IS BECOMING A BIT MORE INTERESTING AND
FAVORABLE FOR HIGHER RAIN CHANCES. SAT INTO SUN THE UPPER RIDGE
OVER THE MID MISS RIVER BASIN SHOULD RETROGRADE BACK AND
STRENGTHEN OVER THE ROCKIES. THIS SHOULD ALLOW FOR MORE NORTHERLY
FLOW ALOFT AND A COUPLE OF SHORT WAVE DISTURBANCES TO MOVE INTO SE
TX FOR THE END OF THE WEEKEND. A MORE PRONOUNCED INVERTED TROUGH
IS EXPECTED TO MOVE INTO SE TX MON MORNING. MOISTURE SHOULD GROW
DEEPER DURING THIS TIME FROM THE EAST WITH PRECIP WATER VALUES
REACH MORE THAN 2 INCHES. THIS AIRMASS HOLDS ONTO THE AREA FOR THE
EARLY PART OF NEXT WEEK AND THE GFS EVEN SHOWS A FRONTAL BOUNDARY
PUSHING INTO TX. ECMWF IS NOT AS PROGRESSIVE WITH THE FRONT BUT
SOMETHING THAT COULD STILL KEEP RAIN CHANCES IN THE FORECAST FOR
NEXT WEEK. FOR NOW 20/30 POPS LOOK GOOD AND PLACED 30 POPS WHERE
CONVECTION LOOKS MOST LIKELY AT THIS POINT AND ALIGNED WITH BEST
MOISTURE AXIS.
39
&&
.AVIATION...
CLOUD COVER IS A BIT MORE EXTENSIVE TODAY. 12Z SOUNDINGS LOOK
FAVORABLE FOR SHOWERS TO DEVELOP AS TEMPERATURES WARM INTO THE
LOWER 90S. BOTH THE NAM AND GFS SHOW PW VALUES EXCEEDING 1.90
INCHES THIS AFTERNOON. RAP MODEL ALSO SHOWS PRECIP DEVELOPING AND
EXPANDING INLAND ON THE SEA BREEZE THIS AFTERNOON. WITH SOME
RELUCTANCE...DECIDED TO ADD VCSH FOR SOUTHERN AND WESTERN TAF
SITES FROM 21-01Z. 43
&&
.MARINE...
HIGH PRESSURE OVER THE EASTERN U.S. WILL ALLOW ONSHORE WINDS TO
PREVAIL THROUGH THE END OF THE WEEK. THE GRADIENT WILL WEAKEN AS
EARLY AS THURSDAY AND WIND SPEEDS ARE EXPECTED TO DECREASE. A WEAK
GRADIENT WILL PREVAIL THROUGH THE WEEKEND. AN UPPER LEVEL
DISTURBANCE WILL APPROACH THE REGION OVER THE WEEKEND AND THIS
FEATURE WILL BRING SCATTERED SHOWERS AND THUNDERSTORMS TO MARINE
AREAS BOTH DAYS. 43
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 74 96 74 96 75 / 10 20 10 20 10
HOUSTON (IAH) 75 94 75 95 75 / 10 20 10 20 10
GALVESTON (GLS) 81 89 81 91 80 / 10 20 10 20 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...39
AVIATION/MARINE...43
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1214 PM CDT TUE JUL 3 2012
.DISCUSSION...
SEE AVIATION DISCUSSION.
&&
.AVIATION...
CLOUD COVER IS A BIT MORE EXTENSIVE TODAY. 12Z SOUNDINGS LOOK
FAVORABLE FOR SHOWERS TO DEVELOP AS TEMPERATURES WARM INTO THE
LOWER 90S. BOTH THE NAM AND GFS SHOW PW VALUES EXCEEDING 1.90
INCHES THIS AFTERNOON. RAP MODEL ALSO SHOWS PRECIP DEVELOPING AND
EXPANDING INLAND ON THE SEA BREEZE THIS AFTERNOON. WITH SOME
RELUCTANCE...DECIDED TO ADD VCSH FOR SOUTHERN AND WESTERN TAF
SITES FROM 21-01Z. 43
&&
.PREV DISCUSSION... /ISSUED 1050 AM CDT TUE JUL 3 2012/
UPDATE...
MORNING FORECAST UPDATE.
DISCUSSION...
AFTER SOME UPPER AIR AND SFC ANALYSIS IT LOOKS LIKE THE UPPER
LEVEL RIDGE IS SOMEWHAT WEAK WITH 590DM HEIGHTS OVER THE S ROCKIES
TO THE PLAINS AND THEN ALONG THE N GULF COAST. IN BETWEEN THERE IS
A SLIGHT WEAKNESS WITH A WEAK VORTICITY CENTER OVER THE ARKLATEX.
AT THE SURFACE A 1018MB SFC HIGH WAS OVER THE N GULF AS WELL WITH
LEE TROUGHING ALONG THE ROCKIES SUPPORTING SE WINDS ACROSS MUCH OF
TX. 12Z LCH SOUNDING HAD 1.9 INCHES OF PRECIP WATER WHICH MAY BE
ON THE HIGH SIDE FOR SE TX WHERE CRP HAD 1.7 INCHES. THIS SEEMS
MORE TYPICAL FOR THE AREA BUT STILL COULD BE ENOUGH MOISTURE TO
SUPPORT CONVECTION WITH ENOUGH HEATING. THAT COULD BE THE ISSUE AS
THERE IS DECENT CLOUD COVER OVER MUCH OF SE TX FROM VIS SATELLITE
IMAGERY AND THIS MAY BE HOLDING TEMPS DOWN A TOUCH IN THE MID 80S.
LOW 90S ARE STILL NOT OUT OF THE QUESTION BUT MAY NOT BE QUITE
ENOUGH TO INITIATE CONVECTION. ALSO WITHOUT GOOD HEATING...WILL
NOT GET STRONG SEA BREEZE BOUNDARY TO SUPPORT CONVECTION. THE MAIN
FORECAST UPDATE WAS TO DROP POPS TO 20 AND MENTION ISO STORMS.
RIGHT NOW THE FORECAST LOOKS ON TRACK BUT MAY TAKE A CLOSER LOOK
AT CONVECTION FOR INDEPENDENCE DAY.
39
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 75 96 75 96 75 / 10 20 10 20 10
HOUSTON (IAH) 76 94 76 95 75 / 10 20 10 20 10
GALVESTON (GLS) 81 89 82 91 81 / 10 20 10 20 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...39
AVIATION/MARINE...43
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1132 PM CDT MON JUL 2 2012
.AVIATION...
/06Z TAFS/
VFR CONDITIONS TO PREVAIL THROUGH THE PERIOD WITH SOUTHEAST WINDS
AROUND 10KTS. MID LEVEL MOISTURE APPEARS THAT IT WILL HANG AROUND
THROUGH THE DAY TOMORROW SO WILL KEEP SKIES BKN THROUGH THE DAY.
PRECIPITATION CHANCES WILL REMAIN LOW SO WILL LEAVE ANY MENTION
OUT OF THE CURRENT TAFS.
DUNN
&&
.UPDATE...
MAIN UPDATE TO THE FORECAST WILL BE TO INCREASE CLOUDS THROUGH
MIDDAY TUESDAY AS MID LEVEL VORTEX NEAR KAUFMAN COUNTY CONTINUES
TO RESULT IN EXTENSIVE MID LEVEL CLOUD COVER. THE INCREASED
CLOUDS WILL LIMIT COOLING TONIGHT AND HAVE BUMPED UP LOWS OVER THE
CENTRAL AND SOUTHEASTERN ZONES. WILL KEEP THE MENTION OF ELEVATED
SHOWERS IN THE FORECAST THROUGH THE OVERNIGHT HOURS BUT DROP POPS
TO 10 PERCENT AS MEASURABLE RAIN LOOKS LIKE IT WILL BE HARD TO
COME BY.
TR.92
&&
.PREV DISCUSSION... /ISSUED 345 PM CDT MON JUL 2 2012/
NORTH TEXAS REMAINS PLACED BETWEEN AN UPPER LEVEL RIDGE TO OUR
EAST AND THE UPPER LEVEL LOW OVER NORTHERN MEXICO. RUC ANALYSIS
AND WATER VAPOR SATELLITE INDICATE A WEAK SHORTWAVE OVER OUR
NORTHWESTERN COUNTIES. THE RAIN ACTIVITY HAS BEEN ISOLATED IN
NATURE FOR MUCH OF THE AFTERNOON WITH A FEW OCCASIONAL LIGHTNING
STRIKES RECORDED. EXPECT ISOLATED SHOWER AND THUNDERSTORM ACTIVITY
TO CONTINUE INTO THE EARLY EVENING HOURS AND THEN QUICKLY DIMINISH
BEFORE OR NEAR SUNSET.
THE SHORTWAVE CURRENTLY OVER OUR NORTHWESTERN COUNTIES IS FORECAST
TO MOVE EAST INTO OUR NORTHEASTERN COUNTIES AND THEN SLIDE BACK
WEST AS THE UPPER LEVEL RIDGE STARTS TO BUILD BACK IN. WITH THIS
WEAKNESS IN THE ATMOSPHERE CONTINUING TONIGHT AND TOMORROW...HAVE
INTRODUCED 20 POPS ACROSS THE REGION AFTER MIDNIGHT TONIGHT AND
CONTINUING THROUGH THE AFTERNOON TOMORROW. OVERNIGHT...ISOLATED TO
SCATTERED LIGHT SHOWERS MAY AGAIN DEVELOP AS THE LOW LEVEL JET
INCREASES AND THINK WE WILL SEE ISOLATED TO SCATTERED RAIN ACTIVITY
AGAIN THROUGHOUT THE DAY ON TUESDAY...MUCH LIKE THE PATTERN OF
ACTIVITY WE EXPERIENCED TODAY.
THE UPPER LEVEL RIDGE WILL START TO STRENGTHEN OVER THE REGION
BEGINNING WEDNESDAY BUT THERE IS A SMALL CHANCE THAT WE COULD SEE
ISOLATED RAIN ACTIVITY ALSO ON WEDNESDAY. HOWEVER...THE FORECAST
SOUNDINGS START TO SHOW THE ATMOSPHERIC COLUMN DRYING OUT
BEGINNING WEDNESDAY AND WITH LOW CONFIDENCE OVERALL THAT THERE
WILL BE SOME RAIN...WILL NOT INTRODUCE POPS ON WEDNESDAY AT THIS
TIME. AS THE UPPER LEVEL RIDGE STRENGTHENS...HIGH TEMPERATURES
WILL CLIMB BACK INTO THE UPPER 90S AND NEAR 100 DEGREES.
HOWEVER...SOME RELIEF MAY OCCUR OVER THE WEEKEND OR BY THE EARLY
PART OF NEXT WEEK. BOTH THE GFS AND ECMWF ARE SHOWING A FEW
DISTURBANCES MOVING INTO NORTH TEXAS FROM THE EAST...ON THE
SOUTHERN PERIPHERY OF THE RIDGE...STARTING ON SATURDAY OR SUNDAY.
THIS IS THE FIRST MODEL RUN THAT THESE SOLUTIONS HAVE SHOWN THIS
BUT GIVEN THE CONSISTENCY...WILL INTRODUCE 20 POPS DURING THE DAY
SUNDAY AND MONDAY. DUE TO THE POTENTIAL FOR RAIN...ALSO INCREASED
CLOUD COVER AND DECREASED TEMPERATURES STARTING SUNDAY.
82/JLD
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 78 95 78 98 78 / 10 20 10 10 10
WACO, TX 78 96 77 97 78 / 10 20 10 10 10
PARIS, TX 72 94 73 95 74 / 10 20 10 10 10
DENTON, TX 77 95 75 97 77 / 10 20 10 10 10
MCKINNEY, TX 76 95 75 97 76 / 10 20 10 10 10
DALLAS, TX 79 95 79 99 79 / 10 20 10 10 10
TERRELL, TX 78 95 75 96 75 / 10 20 10 10 10
CORSICANA, TX 78 94 75 95 76 / 10 20 10 10 10
TEMPLE, TX 75 94 73 95 76 / 10 20 10 10 10
MINERAL WELLS, TX 73 95 73 98 73 / 10 20 10 10 10
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
401 AM CDT TUE JUL 3 2012
.SHORT TERM...TODAY THROUGH THURSDAY
400 AM CDT TUE JUL 3 2012
VERY DANGEROUS HEAT EXPECTED THROUGH THIS TIME PERIOD.
AT 3 AM...WATCHING A LINE OF THUNDERSTORMS FROM REDWOOD FALLS
MINNESOTA NORTHEAST TO RICE LAKE...AND THEN EAST TOWARD
RHINELANDER. THE 03.04Z MPX TAMDAR SOUNDINGS SHOWED THAT AS THE
LINE TO OUR NORTHWEST SLIDES SOUTHEAST TOWARD OUR AREA IT WILL BE
RUNNING INTO A MORE HOSTILE ENVIRONMENT WITH STRONG CAPPING
ALOFT...THEREFORE THINKING THAT THAT THE LINE WILL LIKELY
DISSIPATE BEFORE MOVING INTO SOUTHEAST MINNESOTA SO LEFT MUCH OF
THAT AREA DRY. MEANWHILE IT IS A LITTLE CERTAIN NORTH OF A
ZUMBROTA TO WISCONSIN DELLS LINE...SO INTRODUCED A 20 TO
40 PERCENT PROBABILITY TO COVER THIS POSSIBILITY. THE 0-3 KM SHEAR
CLIMBS INTO THE 20 TO 25 KNOT RANGE ACROSS NORTH-CENTRAL
WISCONSIN...SO CANNOT COMPLETELY RULE OUT AN ISOLATED SEVERE WIND
REPORT IN THIS AREA. FOR THE REMAINDER OF THE FORECAST AREA
NEITHER THE 0-3 KM OR 0-6 KM SHEAR IS THAT IMPRESSIVE...SO
THINKING THAT THERE WILL NOT BE ANY SEVERE WEATHER IN THESE AREAS.
BOTH THE NAM/WRF AND ECMWF SUGGEST THAT THE 925 MB TEMPERATURES WILL
BE AROUND 30C TODAY...AND IN THE LOWER 30S FOR BOTH WEDNESDAY AND
THURSDAY. IN ADDITION...THE 850 MB TEMPERATURES WILL BE AROUND 22C
TODAY...AND 24 TO 25C FOR WEDNESDAY AND THURSDAY. THESE
TEMPERATURES IN THE ECMWF ARE 2 TO 2.5 STANDARD DEVIATION ABOVE
NORMAL THROUGH THIS TIME PERIOD. AS RESULT EXPECT TEMPERATURES
RANGING FROM THE MID 90S TO AROUND 100 TODAY...95 TO 105 ON
INDEPENDENCE DAY...AND 100 TO TO 105 ON THURSDAY. HEAT INDICES
RANGE FROM 95 TO 105 TODAY...AND WIDESPREAD 105 TO 115 ON
INDEPENDENCE DAY AND THURSDAY. AT NIGHT...TEMPERATURES WILL
LIKELY ONLY COOL OFF INTO THE MID AND UPPER 70S. THERE MAY BE EVEN
A FEW PLACES THAT STAY IN THE LOWER 80S. DUE TO THE LONG DURATION
OF THIS HEAT...IT WAS THE CONSENSUS TO UPGRADE THE EXISTING HEAT
ADVISORY TO AN EXCESSIVE HEAT WARNING FOR THE SAME TIME PERIOD.
FOR THIS AFTERNOON AND EVENING...THE ECMWF AND GEM SUPPORT THE
POSSIBILITY OF SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING
ALONG THE WARM FRONT LOCATED ACROSS CENTRAL AND NORTH-CENTRAL WISCONSIN.
THE 0-3 KM SHEAR CLIMBS INTO THE 20 TO 25 KNOT RANGE. MEANWHILE
THE 0-6 KM SHEAR REMAINS BELOW 25 KNOTS. AS A RESULT...COULD NOT
COMPLETELY RULE OUT AN ISOLATED SEVERE WIND REPORT. THIS IS
ASSUMING THAT CONVECTION IS ABLE TO FORM.
FOR TONIGHT AND INDEPENDENCE DAY...THE MODELS ARE IN GENERAL
AGREEMENT THAT MODERATE 850 MB MOISTURE TRANSPORT WILL DEVELOP
SOMEWHERE OVER NORTHEAST SOUTH DAKOTA OR EASTERN NORTH DAKOTA.
OVERALL THE ARW IS THE FURTHEST SOUTH WITH THIS SYSTEM. MEANWHILE
THE LARGE SCALE MODELS SUGGEST THAT THIS SYSTEM WILL DEVELOP MUCH
FURTHER NORTH. THIS IS ACTUALLY VERY IMPORTANT...BECAUSE THE
FORWARD PROPAGATING CORFIDI VECTORS SUGGEST THAT THIS SYSTEM WILL
MOVE EAST TONIGHT...AND THEN MOVE SOUTHEAST ON INDEPENDENCE DAY.
THINKING THAT THE BEST PROBABILITY WILL BE THAT IT WILL TAKE ON A
FURTHER NORTH TRACK...THEREFORE...ONLY PUT 20 PERCENT
PROBABILITIES OF PRECIPITATION FOR NORTH-CENTRAL WISCONSIN.
.LONG TERM...THURSDAY NIGHT THROUGH MONDAY
400 AM CDT TUE JUL 3 2012
VERY DANGEROUS HEAT EXPECTED THROUGH FRIDAY EVENING.
FROM THURSDAY NIGHT THROUGH SATURDAY...A COLD FRONT WILL MOVE
SLOWLY SOUTH THROUGH THE FORECAST AREA. WITH SOME CAPPING ALOFT AND
ONLY WEAK CONVERGENCE...NOT PLANNING ON WIDESPREAD THUNDERSTORM
ACTIVITY ALONG IT...SO JUST WENT WITH 20 TO 40 PERCENT
PRECIPITATION PROBABILITIES. SOUTH OF THIS FRONT TEMPERATURES WILL
BE IN THE MID 90S TO LOW 100S...SO ENDED THE EXCESSIVE HEAT
WARNING ON FRIDAY EVENING. IF THE ECMWF IS CORRECT...THIS WARNING
MAY HAVE TO BE EXTENDED INTO SATURDAY EVENING FOR NORTHEAST IOWA
AND SOUTHWEST WISCONSIN.
&&
.AVIATION...
1130 PM CDT MON JUL 2 2012
SHRA/TS HAVE FIRED ALONG AND NORTH/EAST OF A SFC FRONT EXTENDING
FROM NORTHERN MN INTO NORTHERN/EASTERN WI. THE STORMS WERE FEEDING
OFF AMPLE UNSTABLE AIR AND A FETCH OF LOW LEVEL MOISTURE. SOUTH OF
THERE...LITTLE CONVERGENCE AND A CAP HAVE PREVENTED ANY SHRA/TS
DEVELOPING. MOST OF THE STORMS WERE MOVING EAST EXCEPT FOR AN MCS
WHICH WAS DIVING SOUTHEAST ACROSS NORTHERN WI. RAP CORFIDI VECTORS
WANT TO TAKE IT DUE SOUTH...BUT CURRENT TRACK WOULD KEEP IT EAST OF
KLSE. LATEST HRRR CONTINUES TO SUGGEST SOME CONVECTION IS POSSIBLE
FOR KRST/KLSE. DON/T REALLY SEE A KICKER...SO CONFIDENCE ISN/T HIGH
IN THIS SCENARIO. WILL STAY DRY FOR NOW...BUT OBVIOUSLY CONDITIONS
WILL HAVE TO BE MONITORED CLOSELY.
&&
.CLIMATE...
400 AM CDT SAT JUN 30 2012
NEAR RECORD OR RECORD TEMPERATURES ARE EXPECTED FROM TODAY THROUGH
THURSDAY.
THE LAST TIME THAT BACK TO BACK 100 DEGREE DAYS OCCURRED IN
LA CROSSE WAS JULY 13-14 1995...AND FOR ROCHESTER IT WAS
AUGUST 23-24 1948.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
400 AM CDT TUE JUL 3 2012
WI...EXCESSIVE HEAT WARNING UNTIL 10 PM CDT FRIDAY FOR WIZ017-029-
032>034-041>044-053>055-061.
MN...EXCESSIVE HEAT WARNING UNTIL 10 PM CDT FRIDAY FOR MNZ079-086>088-
094>096.
IA...EXCESSIVE HEAT WARNING UNTIL 10 PM CDT FRIDAY FOR IAZ008>011-018-
019-029-030.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION.....RIECK
CLIMATE......AJ/BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1130 PM CDT MON JUL 2 2012
.SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT
309 PM CDT MON JUL 2 2012
MAIN FORECAST CHALLENGE REMAINS THE HEAT FOR THE REMAINDER OF THE
WEEK AND SPECIFICALLY DEW POINTS AND RESULTANT HEAT INDICES. ALSO OF
CONCERN IS CONVECTIVE POTENTIAL...MAINLY IN AREAS NORTH OF
INTERSTATE 94.
18Z SURFACE ANALYSIS SHOWS FRONTAL BOUNDARY ACROSS THE FORECAST
AREA...GENERALLY ALONG INTERSTATE 94. TEMPERATURES TO THE SOUTH OF
THIS BOUNDARY HAVE RISEN INTO THE 90S WITH HEAT INDEX VALUES BETWEEN
95 AND 103. TO THE NORTH...TEMPERATURES WERE JUST IN THE 80S.
02.00Z MODELS IN A LITTLE BETTER AGREEMENT WITH THE CONVECTIVE
POTENTIAL TONIGHT INTO EARLY TUESDAY...SO CONFIDENCE HIGHER IN
SEEING SOME CONVECTION ACROSS THE NORTHERN AREAS OF THE FORECAST
AREA. MODELS CONTINUE CONSISTENT WITH LARGE RIDGE DOMINATING THE
CENTRAL PORTION OF THE CONUS THROUGH THE REMAINDER OF THE PERIOD.
IN THE NEAR TERM...SPC MESO PAGE SHOWING MOISTURE CONVERGENCE ALONG
AND NORTH OF THE BOUNDARY. VISIBLE SATELLITE IMAGERY SHOWING A
CUMULUS FIELD DEVELOPING IN THE SAME AREA. SHEAR REMAINS SOMEWHAT
LIMITED...GENERALLY 20 TO 30 KNOTS IN THE LOWEST 3 KILOMETERS OF THE
ATMOSPHERE. THUS DO EXPECT SOME CONVECTION TO AFFECT AREAS NORTH OF
INTERSTATE 94 THIS EVENING...PERHAPS JUST ON THE FRINGES OF THE
FORECAST AREA. HRRR HAS BEEN VERY CONSISTENT WITH CONSECUTIVE
RUNS...WHICH ALSO MATCHES WITH THE NAM. SHEAR DIMINISHES AS THE
EVENING WEARS ON AND EXPECT THIS TO DIE OUT. FOCUS THEN TURNS TO
CONVECTION NOW OVER NORTH DAKOTA. THIS EXPECTED TO DEVELOP INTO AN
MCS AND DIVE EAST- SOUTHEAST TOWARDS THE NORTHERN SECTIONS OF THE
FORECAST AREA LATE TONIGHT AND EARLY TUESDAY AS DEPICTED BY THE
NAM AND GFS. THUS HAVE KEPT PROBABILITIES IN ACROSS THE FAR NORTH
LATE TONIGHT AS WELL. TRACK AND STRENGTH IS STILL UNCERTAIN SO
KEPT PROBABILITIES IN THE 20 TO 40 PERCENT RANGE.
MCS WILL PUSH EAST TUESDAY MORNING....WITH UPPER RIDGE CONTINUING TO
BUILD NORTHWARD AS WARM FRONT PUSHES INTO NORTHERN WISCONSIN. THIS
PATTERN IS THEN EXPECTED TO CONTINUE THROUGH THE REMAINDER OF THE
FORECAST PERIOD. 850MB TEMPERATURES CONTINUE TO CLIMB INTO THE MID
AND UPPER 20S CELSIUS. THIS WILL RESULT IN TEMPERATURES WELL INTO
THE 90S AND PERHAPS SOME LOW 100S IN SOME OF THE WARMER LOCATIONS.
HEAT INDICES LOOK TO RANGE FROM 95 TO 105 FOR THE WARMER PORTIONS OF
THE DAY. ONE CAVEAT...IS DEW POINT MIXING DURING THE AFTERNOON
HOURS WHICH MAY RESULT IN SLIGHTLY LOWER HEAT INDICES.
HOWEVER...THESE LOWER DEW POINTS MAY THEN RESULT IN SLIGHTLY
HIGHER AMBIENT TEMPERATURES. CONFIDENCE IS HIGH ENOUGH TO WARRANT
THE EXTENDED HEAT ADVISORY NOW IN EFFECT AND DID GO AHEAD AND
EXPAND THE HEAT ADVISORY INTO CLARK AND TAYLOR COUNTIES.
.LONG TERM...FRIDAY THROUGH MONDAY
309 PM CDT MON JUL 2 2012
UPPER RIDGE STAYS FIRMLY IN PLACE THURSDAY AND FRIDAY...BUT THEN
BEGINS TO FLATTEN ON FRIDAY AS SHORTWAVES TRAVERSE ACROSS ITS TOP.
THE HEAT WILL CONTINUE THROUGH FRIDAY WITH HEAT ADVISORIES REMAINING
IN EFFECT THROUGH FRIDAY EVENING. A COLD FRONT LOOKS TO DROP INTO
THE AREA SATURDAY/SATURDAY NIGHT AS RIDGE BREAKS DOWN OVER THE GREAT
LAKES. THESE WILL BRING TEMPERATURES BACK TO NEAR NORMAL BY SUNDAY
AND MONDAY. CONVECTIVE POTENTIAL LOOKS LIMITED UNTIL RIDGE BREAKS
DOWN THIS WEEKEND.
&&
.AVIATION...
1130 PM CDT MON JUL 2 2012
SHRA/TS HAVE FIRED ALONG AND NORTH/EAST OF A SFC FRONT EXTENDING
FROM NORTHERN MN INTO NORTHERN/EASTERN WI. THE STORMS WERE FEEDING
OFF AMPLE UNSTABLE AIR AND A FETCH OF LOW LEVEL MOISTURE. SOUTH OF
THERE...LITTLE CONVERGENCE AND A CAP HAVE PREVENTED ANY SHRA/TS
DEVELOPING. MOST OF THE STORMS WERE MOVING EAST EXCEPT FOR AN MCS
WHICH WAS DIVING SOUTHEAST ACROSS NORTHERN WI. RAP CORFIDI VECTORS
WANT TO TAKE IT DUE SOUTH...BUT CURRENT TRACK WOULD KEEP IT EAST OF
KLSE. LATEST HRRR CONTINUES TO SUGGEST SOME CONVECTION IS POSSIBLE
FOR KRST/KLSE. DON/T REALLY SEE A KICKER...SO CONFIDENCE ISN/T HIGH
IN THIS SCENARIO. WILL STAY DRY FOR NOW...BUT OBVIOUSLY CONDITIONS
WILL HAVE TO BE MONITORED CLOSELY.
&&
.CLIMATE...
400 AM CDT SAT JUN 30 2012
VERY CONCERNED ABOUT THE POSSIBILITY OF A FLASH DROUGHT DEVELOPING
ALONG AND SOUTH OF THE INTERSTATE 90 CORRIDOR. EVAPOTRANSPIRATION
COULD RESULT IN DAILY LOSSES OF 0.35 TO 0.40 INCH FROM THE SOILS.
IN ADDITION...THE CORN CROP COULD BE USING A 0.25 TO 0.30 OF AN
INCH PER DAY. THIS IS ITS HIGHEST USAGE FOR ITS LIFE CYCLE. RAIN
IS CRITICAL FOR THE NEXT TWO WEEKS SINCE THIS IS WHEN IT WILL BE
CREATING ITS EARS.
LA CROSSE RECORD HIGHS THIS WEEK ARE ALL IN THE 100-105 RANGE.
MOST OF THESE SHOULD BE SAFE. HOWEVER...IT IS LIKELY WE WILL BE
NEAR THESE...ESPECIALLY IF LITTLE IN THE WAY OF CONVECTION OCCURS
THE NEXT FEW DAYS. ROCHESTER IS IN A SIMILAR SITUATION WITH THE
RECORD HIGHS MAINLY BETWEEN 100-105. ONE EXCEPTION TO THIS IS ON
THE 4TH WITH A RECORD HIGH OF 98. THAT STILL SEEMS SAFE AT THIS
TIME.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
309 PM CDT MON JUL 2 2012
WI...HEAT ADVISORY UNTIL 10 PM CDT FRIDAY FOR WIZ017-029-032>034-
041>044-053>055-061.
MN...HEAT ADVISORY UNTIL 10 PM CDT FRIDAY FOR MNZ079-086>088-094>096.
IA...HEAT ADVISORY UNTIL 10 PM CDT FRIDAY FOR IAZ008>011-018-019-029-
030.
&&
$$
SHORT TERM...RABERDING
LONG TERM....RABERDING
AVIATION.....RIECK
CLIMATE......AJ/BOYNE
AREA FORECAST DISCUSSION
NWS TUCSON AZ
925 PM MST WED JUL 4 2012
.SYNOPSIS...EXPECT A FEW LINGERING SHOWERS WILL OCCUR EAST OF TUCSON
TONIGHT. MUCH LESS ACTIVITY THURSDAY AND FRIDAY AS THE ATMOSPHERE
RECOVERS...THEN A CHANCE OF MAINLY AFTERNOON AND EVENING SHOWERS AND
THUNDERSTORMS THIS WEEKEND INTO THE MIDDLE OF NEXT WEEK.
&&
.DISCUSSION...MOSTLY CLEAR SKIES FROM TUCSON WWD AND PARTLY CLOUDY
SKIES EAST OF TUCSON AT THIS TIME. KEMX WSR-88D DETECTED ISOLATED
MOSTLY LESS THAN 30 DBZ ECHOES GENERALLY EAST OF KSAD-KFHU LINE.
WATER VAPOR IMAGERY DEPICTED CYCLONIC CIRCULATION FEATURE TO BE
CENTERED OVER SANTA CRUZ COUNTY AT 0420Z. THIS SYSTEM PROVIDED
BROAD-SCALE ASCENT ACROSS THE AREA EARLIER TODAY...AND WILL CONTINUE
TO MOVE NWD TONIGHT.
BASED ON THE 05/00Z NAM AS WELL AS RUC13 AND RUC HRRR SOLUTIONS...
HAVE OPTED TO MAINTAIN A SLIGHT CHANCE OF SHOWERS/TSTMS ACROSS ERN
SECTIONS THE REST OF TONIGHT. APPEARS THAT ANY MEASURABLE PRECIP
SHOULD END AROUND 2-3 AM MST...OR BY DAYBREAK THUR AT THE LATEST.
MOSTLY CLEAR SKIES TO PARTLY CLOUDY SKIES THE REST OF TONIGHT FROM
TUCSON WWD...AND PARTLY CLOUDY TO MOSTLY CLOUDY SKIES ACROSS ERN
SECTIONS. MUCH LESS CONVECTIVE ACTIVITY IS ON TAP THUR. 05/00Z NAM
LIMITS MEASURABLE PRECIP TO GREENLEE/GRAHAM/COCHISE COUNTIES WITH
PRECIP-FREE CONDITIONS ELSEWHERE. EVEN LESS CONVECTIVE DEVELOPMENT
PROGGED FRI AFTERNOON AND FRI EVENING...AT LEAST ACCORDING TO THIS
VERSION OF THE NAM.
UPDATES WERE MADE TO THE OFFICIAL FORECAST FOR THE REST OF TONIGHT.
WILL DEFER ADDITIONAL REFINEMENTS FOR THUR-FRI TO SUBSEQUENT SHIFTS.
PLEASE REFER TO THE PREVIOUS DISCUSSION SECTION FOR FURTHER DETAIL.
&&
.PREV DISCUSSION...AS THE UPPER LOW MOVES NORTH EXPECTING THE RAIN
CHANCES TO DECREASE THROUGH THE NIGHT WITH ONLY ISOLATED POPS
EXPECTED FOR THURSDAY AND FRIDAY AS THE WEAK TROUGH TO OUR WEST
PUSHES MOISTURE TO THE EAST WITH MODEL PRECIPITABLE WATER VALUES
DROPPING DOWN TO BETWEEN THREE QUARTERS OF AN INCH TO ONE INCH FOR
THURSDAY AND FRIDAY...WHICH IS CONSIDERABLY LESS THAN THE 1.7 INCH
PW FROM THIS MORNINGS SOUNDING.
AS THE HIGH RETROGRADES TO THE WEST...MODELS DEPICT A RETURN TO
EASTERLY MID LEVEL FLOW WHICH WILL HELP TO BRING IN ADDITIONAL
MOISTURE FOR A RETURN TO MORE OF A TYPICAL MONSOON FORECAST
BEGINNING SATURDAY.
&&
.AVIATION...ISOLD-SCT -TSRA/-SHRA MAINLY EAST OF A KSAD-KFHU LINE
THURSDAY AFTERNOON AND THURSDAY EVENING. OTHERWISE...FEW-SCT CLOUDS
MOSTLY ABOVE 10K FT AGL THRU THURSDAY MORNING...THEN FEW-BKN CLOUDS
AT 6-10K FT AGL THURSDAY AFTERNOON AND THURSDAY EVENING. SURFACE
WIND GENERALLY LESS THAN 10 KTS THRU THURSDAY EVENING OR 06/06Z.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...ISOLATED TO SCATTERED THUNDERSTORMS EAST OF TUCSON
THURSDAY AND FRIDAY DURING THE AFTERNOON AND EVENING HOURS WITH DRY
CONDITIONS ELSEWHERE. A CHANCE OF MAINLY AFTERNOON AND EVENING
THUNDERSTORMS WILL THEN OCCUR ACROSS THE AREA FRIDAY THROUGH
WEDNESDAY.
&&
.CLIMATE...2 RECORDS WERE ESTABLISHED AT TUCSON INTERNATIONAL
AIRPORT ON JULY 4. THE RAINFALL AMOUNT OF 0.78 INCH BREAKS THE
PREVIOUS RECORD OF 0.70 INCH SET IN 1921. ALSO...THE HIGH TEMP OF
86 DEGREES IS A NEW RECORD LOW MAXIMUM TEMP FOR JULY 4. THE PREVIOUS
RECORD LOW MAXIMUM FOR JULY 4 WAS 90 DEGREES SET IN 1962.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
$$
WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1138 PM MDT WED JUL 4 2012
.AVIATION...STILL SOME SHOWERS OVER THE MOUNTAINS LATE THIS
EVENING...WITH A FEW POCKETS OF MVFR CONDITIONS NEAR THE
CONTINENTAL DIVIDE. EXPECT MOST PRECIP TO WIND DOWN BY 09Z...WITH
AT LEAST PARTIAL CLEARING BY 12Z. ANOTHER ROUND OF -TSRA WILL BE
POSSIBLE MAINLY ACROSS THE MOUNTAINS ON THURSDAY...WITH STEERING
CURRENTS LOOKING UNFAVORABLE TO CARRY STORMS VERY FAR EAST ONTO THE
PLAINS. FOR THE TAF SITES...BEST CHANCE FOR TSRA WILL BE AT
KALS...WITH LOWER CHANCES KCOS/KPUB. STILL A THREAT OF OUTFLOW
WINDS GUSTING 35-45 KNOTS AT ALL SITES FROM 22Z-02Z.
&&
.PREV DISCUSSION... /ISSUED 310 PM MDT WED JUL 4 2012/
SHORT TERM...
(TONIGHT AND THURSDAY)
SFC DEW POINTS HAVE DROPPED OFF ACROSS THE PIKES PEAK REGION...WITH
READINGS IN THE LOWER 30S ACROSS THE LOWER ELEVATIONS OF EL PASO
COUNTY...AND MID TO UPPER 30S ACROSS TELLER COUNTY. CONVECTION
HAS BEEN SPARSE...AND SPC MESOANALYSIS SHOWING CAPE VALUES UNDER
100 J/KG FOR THIS REGION. DEW POINTS ARE A LITTLE HIGHER TO THE
SOUTH AND WEST WHERE CAPE VALUES ARE APPROACHING 1000 J/KG.
QUANDARY FOR THIS FORECAST PACKAGE IS WHAT TO DO WITH FLASH FLOOD
WATCH FOR THE WALDO CANYON BURN SCAR. SUCCESSIVE HIGH RES MODEL
RUNS...SUCH AS HRRR...AND RUC13 ARE STILL SHOWING VERY LITTLE
ACTIVITY ACROSS THE PIKES PEAK REGION. WINDS HAVE BEGUN TO SWITCH
AROUND FROM THE NORTHEAST TO EAST ACROSS EL PASO COUNTY...AND
MODELS DO BRING SOME LOWER 40 DEW POINTS BACK WESTWARD INTO THE
REGION BY 01-02Z (7-8 PM). BUT BY THIS TIME...PEAK HEATING IS LOST
WHICH SHOULD LIMIT STORM STRENGTH. HUNTING AROUND IN THE MOISTURE
PLUME FOR ANY EMBEDDED SHORTWAVES TO HELP ENHANCE -TSRA
COVERAGE...MOST OBVIOUS WAVE IS BACK ACROSS SOUTHERN AZ...AND IS
EASIEST TO TRACK IN THE PRESSURE FIELDS ON THE 1.5PV SURFACE...OR
IN THE UPPER LEVEL POT VORT FIELDS. THIS WAVE TRACKS TO THE NORTH
ACROSS AZ/UT FOR TOMORROW. COULD BE A WEAK FEATURE BACK ACROSS THE
4 CORNERS REGION ENHANCING TSRA COVERAGE ACROSS SW CO...BUT HARD
TO SAY FOR CERTAIN. BOTTOM LINE IS...WITH LOW LEVEL MOISTURE
LOOKING A LITTLE DRIER THAN YESTERDAY...THINK THREAT FOR FLASH
FLOODING HAS DECREASED...AND GUSTY OUTFLOW WIND POTENTIAL HAS
INCREASED. WILL WATCH LATEST RADAR TRENDS TOWARDS THE PACKAGE
ISSUANCE...AND WILL TAKE DOWN THE FLASH FLOOD WATCH FOR THE WALDO
CANYON BURN SCAR IF TRENDS CONTINUE AS THEY HAVE.
MEANWHILE...WITH PRECIP WATERS OUT WEST RUNNING UP TO 140 PERCENT OF
NORMAL...LOCALLY HEAVY RAIN STILL POSSIBLE...ESPECIALLY ALONG THE
CONTDVD...SO WILL CONTINUE TO MONITOR THIS AREA CLOSELY FOR
LOCALIZED RUN-OFF PROBLEMS.
CONVECTION MAY CONTINUE ACROSS PORTIONS OF THE SE PLAINS TONIGHT AS
LOW LEVEL JET INCREASES. SO WILL MAINTAIN AN AXIS OF HIGHER POPS
EAST OF THE I-25 CORRIDOR UNTIL 06Z...THEN TAPER IT BACK DURING
THE LATE NIGHT HOURS. WILL ALSO MAINTAIN SOME LOW POPS OUT WEST
UNDER THE MONSOON PLUME.
FOR THURSDAY...MODELS KEEP MAJORITY OF THE PRECIPITATION CONFINED TO
THE MOUNTAIN AREAS AS SOUTHERLY WINDS SPREAD BACK IN ACROSS ALL OF
THE SOUTHEAST PLAINS...PUSHING BOUNDARY TO THE NORTH OF THE REGION.
LOOKS LIKE DRIER AIR WILL BE PUSHING INTO EASTERN PORTIONS OF THE
FORECAST AREA ALONG LEADING EDGE OF PV LOBE...CURRENTLY LOCATED
ACROSS WRN TX...WHICH DECREASES PRECIP WATERS SOME FOR THE I-25
CORRIDOR AND SE PLAINS. THIS SHOULD DIMINISH HEAVY RAIN POTENTIAL
ACROSS THE PLAINS AND I-25 CORRIDOR...THOUGH WITH GUSTY SOUTHERLY
AFTERNOON WINDS...RHS MAY BE APPROACHING CRITICAL FIRE WEATHER
THRESHOLDS. THIS WILL CONTINUE TO BE MONITORED...BUT FOR NOW IT
REMAINS A LITTLE TOO MOIST FOR ANY FIRE WEATHER HIGHLIGHTS.
MEANWHILE...MTN AREAS...ESPECIALLY ALONG THE CONTINENTAL DIVIDE
WILL HAVE ANOTHER SHOT OF SOME LOCALLY HEAVY RAINFALL WITH
THUNDERSTORMS...SO WILL KEEP HIGHEST POPS OUT THAT WAY. -KT
LONG TERM...
(THURSDAY NIGHT THROUGH WEDNESDAY)
EXTENDED RANGE MODELS ARE IN DECENT AGREEMENT WITH THE MID AND UPPER
LEVEL PATTERN. EARLY IN THE PERIOD H5 HIGH PRESSURE IS CENTERED OVER
THE CENTRAL PLAINS...BUT GRADUALLY RETROGRADES AND AMPLIFIES OVER
THE ROCKY MOUNTAIN REGION THIS WEEKEND. RIDGE BECOMES ENTRENCHED
OVER THE WESTERN U.S. BY THE MIDDLE OF NEXT WEEK.
AT THE SURFACE...DIFFERENCES BECOME MORE PRONOUNCED IN THE GFS AND
ECMWF. ECMWF CONTINUES ITS TREND OF HOLDING THE MID LEVEL MOISTURE
PLUME ALONG AND WEST OF THE CONTINENTAL DIVIDE AND INTO SOUTHEAST
WYOMING. ECMWF ALSO NOT AS FAST BRINGING SURFACE FRONT INTO THE CWA
AND FRONT APPEARS TO WOBBLE NORTH AND SOUTH OVER THE WEEKEND BEFORE
FINALLY PUSHING WELL SOUTH SUNDAY NIGHT. EASTERLY
UPSLOPE FLOW...INCREASING LOW LEVEL MOISTURE AND BETTER CHANCE
FOR RAINFALL ON THE PLAINS HOLDS OFF UNTIL MONDAY WITH THIS
SOLUTION. ON THE OTHER HAND...THE GFS HAS THE FRONT MOVING
THROUGH THE CWA FRIDAY AFTERNOON/EVENING WITH EASTERLY UPSLOPE
FLOW BRINGING LOW LEVEL MOISTURE INTO THE AREA THROUGH THE
WEEKEND.
FOR THIS FORECAST...I HAVE CUT BACK POPS ON THE SOUTHEAST PLAINS AND
AREAS ALONG THE SOUTHEASTERN MOUNTAINS. WILL CONTINUE THE HIGHEST
POPS IN THE MOUNTAINS...ESPECIALLY CONTINENTAL DIVIDE AND WESTWARD.
AFTER THIRTEEN CONSECUTIVE DAYS OF HIGH TEMPERATURES AT OR ABOVE 100
DEGREES IN PUEBLO...WE ARE READY FOR A BREAK IN THE VERY WARM TEMPS.
THE ARRIVAL OF THE FRONTAL BOUNDARY AND INCREASING AFTERNOON
CLOUDINESS SHOULD HELP BRING THAT STREAK TO AN END. EXPECT HIGHS IN
THE UPPER 80S TO AROUND 100 ON THE PLAINS...MID 80S IN THE HIGH
VALLEYS AND 60S AND 70S IN THE HIGHER ELEVATIONS FRIDAY. COOLER
TEMPS THIS WEEKEND AND EARLY NEXT WEEK WITH HIGHS IN THE 80S AND 90S
ON THE PLAINS...AND 50S AND 60S IN THE HIGHER ELEVATIONS.
WE ARE CONTINUING TO MONITOR POTENTIAL FOR SIGNIFICANT RAINFALL ON
THE WALDO CANYON BURN AREA. BEST CHANCES FOR SIGNIFICANT
PRECIPITATION WILL BE WHEN THE EASTERLY UPSLOPE FLOW SETS UP AT THE
SURFACE COMBINED WITH THE MID LEVEL MONSOON MOISTURE...PERHAPS THIS
WEEKEND AND EARLY NEXT WEEK. 40
AVIATION...
VFR CONDITIONS EXPECTED AT TAF SITES THROUGH NEXT 24 HOURS. LATEST
MODEL RUNS KEEP MAJORITY OF THE -TSRA AWAY FROM THE TAF SITES...SO
WILL MAINTAIN VCTS FOR NOW. MAIN THREAT WILL BE BE GUSTY ERRATIC
WINDS IN THE 20-40 KT RANGE IF AN ISOLATED STORM CAN GET GOING. KALS
WILL HAVE THE BEST CHANCE OF -TSRA HITTING THE TAF SITE AND WILL
CONTINUE TO MONITOR THE LATEST RADAR TRENDS FOR POTENTIAL UPDATE
WITH A TEMPO GROUP. -TSRA CHANCES SHOULD DIMINISH AFTER
02Z...THOUGH A STRAY THUNDERSTORM OVER THE MTS AND FAR EASTERN
PLAINS MAY CONTINUE THROUGH THE NIGHT. ANOTHER ROUND OF -TSRA WILL
BE POSSIBLE ACROSS THE MOUNTAINS ON THURSDAY...POSSIBLY AFFECTING
THE KALS TAF SITE...THOUGH LOOKS LESS LIKELY TO IMPACT THE KPUB AND
KCOS TAF SITES AT THIS TIME. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
10/44
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
339 AM CDT THU JUL 5 2012
.SYNOPSIS...
ANOTHER VERY WARM NIGHT WITH MUGGY CONDITIONS. TEMPERATURES STILL
HOVERING IN THE MID TO UPPER 70S WITH DEWPOINTS IN THE MID 60S TO
AROUND 70S. SOME INTERESTING THINGS GOING ON OUT THERE TONIGHT. A
COLD FRONT IS APPROACHING IOWA FROM THE NORTHWEST...THAT AS OF A
MIDNIGHT ANALYSIS WAS DRAPED FROM NORTHERN MINNESOTA ACROSS
SOUTHEAST SOUTH DAKOTA...THEN BACK WEST ACROSS NEBRASKA TO NORTHEAST
COLORADO. A VERY NICE LOW LEVEL JET HAS FORMED FROM OKLAHOMA UP
INTO WESTERN IOWA. THIS WAS FEEDING AN MCS UP IN CENTRAL
MINNESOTA...BUT NOW THAT IT HAS MOVED EAST OUT OF THE LOW LEVEL
JET...IT HAS FALLEN APART. INSTEAD...NEW CONVECTION HAS FIRED IN
SOUTHWEST MINNESOTA...AND ADDITIONAL CONVECTION SEEMS TO BE
INITIATING IN NORTHWEST IOWA AND EVEN NORTH CENTRAL IOWA AS OF 3
AM. THERE IS LITTLE IF ANY SURFACE BOUNDARY THAT THIS COULD HAVE
FOCUSED ON...BUT THERE IS A NICE SURGE OF 850MB WAA AND DEEP MOISTURE
CONVERGENCE IN THIS AREA ACCORDING TO THE SPC RAP MESOSCALE ANALYSIS
THAT IT COULD BE FOCUSED ON.
LE
&&
.SHORT TERM...TODAY AND TONIGHT...
MAIN CONCERN FOR TODAY IS FOR CONVECTIVE TRENDS AND OF COURSE...
TEMPERATURES AND DEWPOINTS. THIS MORNINGS CONVECTION OVER CENTRAL
IOWA IS UNLIKELY TO BE ABLE TO PROPAGATE VERY FAR EAST BEFORE IT
MOVES OUT OF ITS MOISTURE FEED AND DISSIPATES. THE RAP MODEL IS
DEPICTING THIS FAIRLY WELL...AND IT SEEMS TO ONLY PULL IT INTO THE
NORTH WESTERN PORTIONS OF THE FORECAST AREA BEFORE IT FALLS APART.
HAVE DECIDED TO INCREASE POPS IN THIS REGION FOR A FEW HOURS THIS
MORNING...BUT THEN LOWER AGAIN FOR THE REMAINDER OF THE MORNING
HOURS. OTHER MODELS ALSO WANT TO POP SOME ISOLATED CONVECTION
ACROSS ABOUT THE NORTHERN HALF OF THE FORECAST AREA DURING THE DAY
TODAY...PERHAPS IN A SIMILAR MODE OF INITIATION. AM NOT TERRIBLY
EXCITED ABOUT THIS AS THE CAP COMES INTO PLAY LATER IN THE DAY AS
MORE HOT DRY AIR IS ADVECTED INTO THE AREA AT 700MB. THUS...HAVE
KEPT POPS TO ISOLATED OR SLIGHT CHANCE AT BEST FOR THE LATE MORNING
AND AFTERNOON HOURS. THIS IS GOING TO INCREASE CLOUDS OVER THE AREA
TODAY...EVEN IF IT IS ONLY SOME CIRRUS BLOWN OFF WESTERN
CONVECTION. THIS WILL ACT TO LIMIT HEATING SOMEWHAT...BUT WITH THE
MIXING AND DRY GROUND STILL FEEL LIKE WE WILL GET WELL INTO THE
UPPER 90S AND TO AROUND 100 TODAY. MAY END UP HAVING TO LOWER HIGH
TEMPS IN ACROSS THE NORTH IF THIS CONVECTION ENDS UP BEING MORE
WIDESPREAD THAN ANTICIPATED...BUT THIS SEEMS UNLIKELY AT THIS TIME.
DEWPOINTS HAVE BEEN A REAL BEAR TO FORECAST LATELY...AND WITH THE
LARGE IMPACT THEY HAVE ON HEAT INDEX VALUES...THEY HAVE BEEN
CRITICAL. TODAY AM USING A LOT OF PERSISTENCE FROM YESTERDAYS
FORECAST...BUT FEEL THAT WITH CONVERGENCE INCREASING AHEAD OF THE
APPROACHING BOUNDARY THIS MAY ACT TO HOLD THEM UP EVEN AS WE GET
SLIGHTLY DEEPER MIXING TODAY. CORN CROP HAS ALSO BEEN ACTING TO
HOLD THEM UP IN RECENT DAYS...BUT WE ARE GETTING FARTHER AWAY FROM
THE MOST RECENT RAINFALL...AND THIS EFFECT MAY TAIL OFF SOMEWHAT.
THUS...AM CONTINUING THE EXCESSIVE HEAT WARNING TODAY AS THE HEAT
INDEX VALUES SHOULD BE IN THE 105-110 RANGE FOR A FAIRLY LARGE
PORTION OF THE AREA. THE FAR SOUTH HAS ESCAPED THIS LATELY AS THE
DEWPOINTS HAVE BEEN MIXING DOWN INTO THE UPPER 60S...BUT TODAY THE
EXTRA HEAT SHOULD EASE THEM OVER THE 105 MARK FOR THE FIRST TIME.
ALSO...WE ARE ON OUR 3RD DAY OF AT LEAST 100 DEGREE HEAT INDEX
VALUES...AND THIS IS GOING TO HAVE A DETRIMENTAL AFFECT ON PEOPLE.
TONIGHT WILL BE ANOTHER VERY WARM AND MUGGY NIGHT AND WITH THE
BOUNDARY JUST NORTH OF THE AREA. HAVE KEPT POPS OUT OF THE AREA FOR
NOW...BUT THIS AFTERNOONS CONVECTIVE TRENDS ARE GOING TO BE KEY FOR
DETERMINING WHAT GOES ON TONIGHT. HOWEVER...THE BETTER MID LEVEL
CONVERGENCE WILL BE FOCUSED OUT WEST ACROSS THE NEBRASKA/SOUTH
DAKOTA REGION AGAIN...WHICH WOULD HAVE TO DRIFT EAST INTO OUR AREA
BEFORE DECAYING. IT IS UNLIKELY TO BE ABLE TO GET THIS FAR BEFORE
IT FALLS APART. MIN TEMPS TO ONLY BE IN THE MID TO UPPER 70S.
LE
.LONG TERM...FRIDAY THROUGH WEDNESDAY...
FORECAST FOCUS ON HOT AND HUMID FRIDAY AND SATURDAY THEN COOLER WITH
COMFORTABLE HUMIDITY FOR MOST OF NEXT WEEK. BY THE MIDDLE OF JULY
THE RIDGE BUILDS AGAIN RETURNING HOT WEATHER TO THE MIDWEST. FOR AT
LEAST THE NEXT 10 DAYS THE ONLY CHANCE OF RAIN WILL BE WITH THE COLD
FRONT SUNDAY OR SUNDAY NIGHT BUT EVEN THIS IS STARTING TO LOOK BLEAK.
FRIDAY AND SATURDAY...HOT AND HUMID TO CONTINUE INTO SATURDAY WITH
FRIDAY LOOKING TO BE A REAL SCORCHER. WILL HAVE WIDESPREAD MAX TEMPS
ON FRIDAY OF AROUND 100 WITH HEAT INDEX VALUES OF AT LEAST 110.
EXCESSIVE HEAT WARNING WILL REMAIN IN PLACE. OF COURSE THIS ASSUMES
FULL SUNSHINE AND NO CLOUD DEBRIS FROM ANY MCS THAT MAY OCCUR TO OUR
NORTH. ANY CLOUDS WOULD KEEP THE VERY HOT TEMPERATURES FROM BEING
REALIZED. THE CONSENSUS IS THEN TO START BRINGING A WEAK COLD FRONT
INTO THE NORTHERN CWA SOMETIME ON SATURDAY. THIS SHOULD BRING A
SLIGHT CHANCE OF STORMS AND MORE CLOUDS LATER IN THE DAY. MAX TEMPS
SHOULD BE STILL HOT BUT NOT AS BAD AS FRIDAY. WILL CONTINUE WITH
AFTERNOON READINGS RANGING FROM 90 ALONG HIGHWAY 20 TO AROUND 100
FROM HIGHWAY 34 SOUTHWARD. HEAT INDEX VALUES SHOULD BE IN THE 100 TO
105 RANGE. THIS MAY REQUIRE A HEAT ADVISORY INSTEAD OF A WARNING FOR
SATURDAY FOR ALL OR A PORTION OF THE CWA. THIS WILL DEPEND ON THE
TIMING OF THE ARRIVING FRONT.
SATURDAY NIGHT THROUGH SUNDAY NIGHT...COVERAGE OF STORMS WILL DEPEND
ON THE TIMING OF THE COLD FRONT. THE GFS HAS BEEN ERRONEOUSLY
DEPICTING LARGE AREAS OF QPF LATELY AND HAS BEEN IGNORED. BUT BASED
ON WHAT IS CURRENTLY HAPPENING THE ECM IS TOO DRY. THE ECM SUGGESTS
THE FRONT MAY ARRIVE SUNDAY MORNING WHICH WOULD BE NOT FAVORABLE FOR
THUNDERSTORMS. SHEAR IS VERY WEAK AND THE THREAT FOR STRONG STORMS
SEEM TO BE DIMINISHING. MAX TEMPS ON SUNDAY WILL BE COOLER WITH MOST
AREAS IN THE 80S TO NEAR 90. WILL HAVE SMALL POPS FOR THE WEEKEND.
THE BAD NEWS IS IF YOU MISS OUT ON THIS RAIN OPPORTUNITY THE MODELS
SUGGEST AN EXTENDED DRY PATTERN SHAPING UP.
EARLY TO MID NEXT WEEK...THE MIDWEST WILL BE IN A NORTHWEST FLOW
WITH A TROUGH IN THE EAST AND RIDGING IN THE ROCKIES. WILL BE MUCH
MORE COMFORTABLE WITH LOW HUMIDITY AND TOLERABLE TEMPERATURES. MAX
TEMPS WILL BE IN THE 80S WITH MIN TEMPS IN THE 60S...WHICH IS MORE
NORMAL FOR THIS TIME OF YEAR. WITH HIGH PRESSURE OVER THE GREAT
LAKES REGION THE WEEK LOOKS DRY.
LATE NEXT WEEK AND BEYOND...RIDGING ALOFT BEGINS STRENGTHENING AGAIN
INTO THE MIDWEST. THIS WILL BRING VERY WARM TO HOT TEMPERATURES BACK
INTO THE REGION BY THE MIDDLE OF JULY BUT ALSO REMAINING DRY. THIS
SCENARIO DESCRIBED ABOVE MAY WORSEN THE DROUGHT CONDITIONS.
HAASE
&&
.AVIATION... /ISSUED 1130 PM CDT WED JUL 4 2012/
UPPER LEVEL RIDGE WILL KEEP CLEAR SKIES AND VERY WARM
TEMPERATURES OVER THE AREA THROUGH THURSDAY NIGHT. VFR CONDITIONS WITH
LIGHT SOUTHWEST WINDS WILL PREVAIL AT ALL SITES...BUT WILL
INCREASE TO AROUND 12 KTS DURING MID DAY HOURS.
ERVIN
&&
.CLIMATE...
RECORD HIGHS FOR JULY 5...
MOLINE.........105 IN 1936
CEDAR RAPIDS...110 IN 1911
DUBUQUE........104 IN 1911
BURLINGTON.....108 IN 1936
RECORD HIGHS FOR JULY 6...
MOLINE.........105 IN 1936
CEDAR RAPIDS...102 IN 1936
DUBUQUE........102 IN 1936
BURLINGTON.....105 IN 1936
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...EXCESSIVE HEAT WARNING UNTIL 7 AM CDT SATURDAY 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...EXCESSIVE HEAT WARNING UNTIL 7 AM CDT SATURDAY FOR BUREAU-
CARROLL-HANCOCK-HENDERSON-HENRY IL-JO DAVIESS-MCDONOUGH-
MERCER-PUTNAM-ROCK ISLAND-STEPHENSON-WARREN-WHITESIDE.
MO...EXCESSIVE HEAT WARNING UNTIL 7 AM CDT SATURDAY FOR CLARK-
SCOTLAND.
&&
$$
AREA FORECAST DISCUSSION
NWS CARIBOU ME
427 AM EDT THU JUL 5 2012
.SYNOPSIS...
AN UPPER LOW WILL CONTINUE TO MOVE EAST THROUGH THE MARITIMES TODAY.
HIGH PRESSURE WILL BRIEFLY BUILD ACROSS THE REGION LATER TODAY
INTO FRIDAY. ANOTHER COLD FRONT WILL APPROACH FROM THE WEST FRIDAY
NIGHT AND CROSS THE REGION SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
CHALLENGE IS HOW MUCH RAINFALL AND TEMPERATURES.
THE LATEST RADAR TRENDS SHOW SHOWERS AND ISOLD TSTMS OVER THE
EASTERN 1/2 OF THE CWA. THE BULK OF THE ACTIVITY IS E OF HOULTON
AND ACROSS THE INTERIOR DOWNEAST AND COASTAL REGIONS. THE LATEST
HRRR AND RUC LINED UP WELL THROUGH 12Z ALTHOUGH A BIT OVERDONE AS
FAR AS AREAL COVERAGE. MANUAL ADJUSTMENTS WERE MADE TO THE POPS TO
FIT BETTER W/THE RADAR AND SATL IMAGERY. THIS MEANS HIGHER PRECIP
CHANCES(60%) IN THE AFOREMENTIONED AREAS THIS MORNING. THE CLOSED
LOW IS SHOWN TO MIGRATE ACROSS THE GULF OF MAINE INTO THE
MARITIMES THIS EVENING. AS IT DOES SO, THE INVERTED TROF FROM THE
SFC LOW WILL SLIDE E. AFTER 12Z, DECIDED ON THE GFS AND ECMWF TO
POPS AS THEY APPEAR TO HAVE A GOOD HANDLE ON THE SYNOPTIC
SITUATION AND AREAL PLACEMENT OF QPF . THEREFORE, THE DECISION WAS
TO GO W/40-50% POPS LATER THIS MORNING INTO THE AFTERNOON FOR
SHOWERS. SOUNDINGS FROM THE GFS NOT OVERLY UNSTABLE W/SBCAPE OF
400-500 JOULES. THIS WILL ALSO BE DEPENDENT ON TEMPERATURES THIS
AFTERNOON. SATL IR IMAGERY DOES SHOW SOME PARTIAL CLEARING THIS
MORNING WHICH WILL AID IN HEATING. LAPSE RATE ARE MEAGER AT BEST
(5.5-6C/KM). SOME COOLING ALOFT IS NOTED. DECIDED TO CARRY ISOLD
TSTMS TO ACCOUNT FOR THIS AWAY FROM THE COAST AND MAINLY ALONG THE
EASTERN 1/2 OF THE CWA ALONG THE CONVERGENCE ZONE. LIGHT FLOW
ALOFT AND HIGH PWS(1.5") AND FZL LVLS OF 12.5 FT WILL LEAD TO
HEAVY RAINFALL IN ANY TSTMS. A BLEND OF THE GFS/ECMWF AND HPC WAS
USED FOR THE QPF W/MANUAL ADJUSTMENTS.
ACTIVITY WINDS DOWN TONIGHT AS THE LOW PULLS E AND LLVL
CONVERGENCE WEAKENS. PARTIAL CLEARING IS EXPECTED LATER TONIGHT
AND THIS COUPLED W/A WET SFC WILL ALLOW FOR SOME FOG FORMATION.
DECIDED TO ADD FOG FOR ALL AREAS. HYDROLAPSE RATES FROM THE MDL
SOUNDINGS SUPPORT FOG POTENTIAL. DAYCREW WILL NEED TO ASSESS THIS
FURTHER TODAY. RAISED DAYCREW/S MINS UP A CATEGORY USING THE LAMP
AND NAM12 TEMPERATURES.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
WINDS WILL TURN SOUTHWEST ON FRIDAY ALLOWING FOR WARMER TEMPERATURES
ACROSS THE FA. A SHORT WAVE MOVING ACROSS FROM THE WEST WILL BRING
THE CHANCE OF LATE DAY SHOWERS AND TSTMS TO MAINLY NORTHERN PORTIONS
OF THE FA. SB CAPES LOOK RATHER MODEST AS DO 0-6 KM SHEAR VALUES SO
SEVERE POTENTIAL NOT LOOKING ALL THAT HIGH. SHOWERS AND TSTMS WILL
LIKELY PERSIST INTO FRIDAY EVENING AS THE SHORT WAVE AND ASSOCIATED
COLD FRONT CROSSES THE REGION. A SECONDARY COLD FRONT COLD FRONT
WILL CROSS THE REGION SATURDAY WITH ANOTHER CHANCE FOR SHOWERS AND
TSTMS. HIGHS ON SATURDAY WILL RANGE FROM THE LOW TO MID 80S NORTH
AND MID TO UPPER 80S DOWNEAST.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AN UPPER LOW WILL REMAIN ACROSS EASTERN CANADA SATURDAY NIGHT INTO
EARLY NEXT WEEK AS SURFACE HIGH PRESSURE BUILD EAST. WEATHER
CONDITIONS DURING THE LONG TERM SHOULD BE MAINLY DRY BUT WITH WEAK
DISTURBANCES MOVING THROUGH COULDN`T RULE OUT AN ISOLATED SHOWER OR
TSTM FROM TIME TO TIME. TEMPERATURES THROUGH THE PERIOD WILL BE NEAR
NORMAL FOR THIS TIME OF YEAR.
&&
.AVIATION /08Z THURSDAY THROUGH MONDAY/...
NEAR TERM: IFR/MVFR CONDITIONS THROUGH MID MORNING AND THEN
CONDITIONS LOOK LIKE THEY WILL IMPROVE TO VFR LATER THIS AFTERNOON
OR EVENING. A RETURN TO MVFR AND POSSIBLY IFR LATER TONIGHT W/FOG
DEVELOPING.
SHORT TERM: SCT TSTMS ARE EXPECTED MAINLY NRN AREAS FRIDAY AND THE
REGION WIDE ON SATURDAY. CONDITIONS SHOULD BE MAINLY VFR THROUGH
THE PERIOD BUT COULD DECREASE TO MVFR IN ANY HEAVIER TSTMS FRIDAY
AND SATURDAY.
&&
.MARINE...
NEAR TERM: NO HEADLINES THIS TERM. WINDS WILL BE GENERALLY LIGHT
FROM THE NNE AT 10 KTS OR LESS. SWELLS WILL BE COMMON THIS TERM
W/PERIODS OF 8-9 SECONDS. STAYED W/DAYCREW ASSESSMENT OF 2-3 FOOT
WAVES.
SHORT TERM: WINDS/SEAS SHOULD BE BELOW SCA LEVELS THROUGH THE PERIOD.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...HEWITT
SHORT TERM...DUDA
LONG TERM...DUDA
AVIATION...HEWITT
MARINE...HEWITT/DUDA
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1232 AM EDT THU JUL 5 2012
.SYNOPSIS...
A COLD FRONTAL SYSTEM WILL MOVE ACROSS THE REGION OVERNIGHT WITH
SHOWERS AND THUNDERSTORMS. HIGH PRESSURE RETURNS LATE THURSDAY
INTO FRIDAY. ANOTHER COLD FRONT WILL APPROACH FRIDAY NIGHT AND
CROSS THE REGION SATURDAY.
&&
.NEAR TERM /THROUGH THURSDAY/...
UPDATE: ADJUSTED THE POPS USING THE HRRR AND RUC AS THESE
MESOSCALE MDLS ARE HANDLING THE SHOWERS/TSTMS AND AREAL PLACEMENT
VERY WELL. AREA OF HIGHEST ACTION WILL PIVOT ESE BUT WEAKEN
OVERNIGHT AS ATMOSPHERE STABILIZES. KEPT TSTMS IN THE FCST FROM
THE CENTRAL HIGHLANDS DOWN TO THE COAST WHERE BEST INSTABILITY
RESIDES. ADJUSTED FIRST 12 HRS OF QPF USING THE GEM AND RADAR
TRENDS. SOME AREAS WILL 0.50-1.00 INCH OF BASIN AVERAGE RAFL IN
THE TSTMS. ADDED AREAS OF FOG OVERNIGHT. BHB ALREADY DOWN TO
1/2-1/4SM.
PREV DISCUSSION: A SECONDARY SURFACE LOW WILL DEVELOP ALONG THE
FRONT AS IT MOVES INTO THE GULF OF MAINE. THIS WILL SHIFT THE AXIS
OF HEAVIEST/STEADIEST PRECIPITATION TOWARD EASTERN MAINE. THE LOW
WILL GRADUALLY MOVE EASTWARD OVERNIGHT AND THURSDAY, WHILE THE
UPPER TROUGH SWINGS OVER THE STATE. THIS WILL KEEPS SHOWERS
AROUND, ESPECIALLY IN EASTERN MAINE, INTO TOMORROW AFTERNOON. THE
PRECIPITATION WILL WANE AND CLOUDS BEGIN TO BREAK UP MID TO LATE
AFTERNOON TOMORROW SOME WEAK RIDGING BUILDS IN BEHIND THE
RETREATING LOW PRESSURE. A FEW PEAKS OF SUN SHOULD ALLOW
TEMPERATURES TO REACH INTO THE LOWER TO MID 70S IN MOST SPOTS.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
THE SHORT TERM WILL BEGIN FAIR THU NGT AFTER ANY REMAINING SHWRS
OVR ERN PTNS OF THE FA ASSOCIATED WITH THE EXITING UPPER LOW NEAR
NOVA SCOTIA DURG THE EVE HRS DISSIPATE. A SFC WIND SHIFT FROM NE
TO WSW FRI WILL BRING MUCH WARMER AIR INTO THE REGION FROM QB ON
FRI AS A S/WV RIDGE CROSSES THE FA.
A S/WV TOPPING THIS RIDGE FROM NRN ONT PROV COULD BRING MSLY NRN
PTNS OF THE FA TSTMS BEGINNING LATE FRI AFTN AND CONTG WELL INTO
THE NGT HRS. WITH MOST OF THE DEEP LAYER RH WELL N OF THE FA DURG
THIS TM FRAME...WE KEPT POPS CAPPED IN THE HI CHC CAT FOR THE TM
BEING. HOWEVER...THOSE STORMS THAT DUE FORM WILL BE BENEFITED BY
MDTLY STRONG DVRG HI ALF...WITH MODEST AFTN SB CAPES OF ARND 1000
J/KM AND ABOUT 25 TO 35 KT OF 0-6KM DEEP LAYER BULK SHEAR.
THE SFC COLD FRONT FOLLOWS THE LEAD S/WV THAT PRODUCES CNVCTN FRI
NGT ON SAT...CROSSING THE FA DURG THE AFTN AND EVE HRS. ANOTHER
ROUND OF SCT TO PERHAPS BKN LN OF TSTMS IS POSSIBLE MSLY ACROSS E
CNTRL AND DOWNEAST PTNS OF THE REGION...BUT GIVEN VERY MODEST SB
CAPE VALUES DURG THIS TM FRAME...WE KEPT POPS MSLY AT 40 PERCENT
ATTM.
AFT A MILD NGT FRI NGT...HI TEMPS SAT LOOK TO BE WARMEST OVR CNTRL
AND DOWNEAST AREAS AS NRN PTNS OF THE FA EXPERIENCE A COLD FRONTAL
PASSAGE MID TO LATE AFTN.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
ANY REMAINING TSTMS FROM SAT AFTN SHOULD EXIT S OF THE FA AND OUR
COASTAL WATERS BY LATE SAT NGT. SUN SHOULD START FAIR...BUT
BUILDING CU DUE TO COLD AIR ALF ASSOCIATED WITH REMNANT UPPER
TROUGHINESS OVR ERN CAN COULD RESULT IN ISOLD TO SCT SPRINKLES BY
AFTN. SLGT CHC POPS WERE INCLUDED IN GRIDS...BUT OF COURSE NOT
MENTIONED WITHIN OUR LEGACY ZONE FCST PRODUCTS. HI TEMPS SUN WILL
BE ABT 5 TO 10 DEG F COOLER THAN SAT. ANY REMAINING SHWRS SHOULD
DISSIPATE DURG SUN NGT...WITH MON LOOKING FAIR...BUT ANOTHER FEW
DEG COOLER ACROSS MOST OF THE FA WITH LITTLE IF ANY SHWR ACTIVITY.
ANOTHER WEAK S/WV APCHG FROM CNTRL CAN COULD BRING SOME CLDNSS AND
A SLGT CHC OF SHWRS TO THE REGION LATE MON NGT AND ERLY TUE MORN...
OTHERWISE FAIR CONDITIONS AND A WRMG TREND IS XPCTD INTO MIDWEEK.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
NEAR TERM: MVFR WITH LOCAL IFR EXPECTED THROUGH THE OVERNIGHT.
SHOWERS AND SCATTERED THUNDERSTORMS ALSO EXPECTED OVER MUCH OF THE
AREA AS WELL WITH FOG EXPECTED GENERALLY FROM 06Z-11Z. KBGR AND
KBHB STAND THE BEST CHANCES OF SEEING ANY IFR IN THIS FOG, THOUGH
CEILINGS AT KFVE MAY DROP BELOW 1000 FT AT TIMES. BHB IS ALREADY
DOWN TO 1 MILE. CONDITIONS WILL GRADUALLY IMPROVE THROUGH THE
AFTERNOON HOURS.
SHORT TO LONG TERM: VFR XPCTD ALL TAF SITES THU NGT THRU MON XCPT
BRIEFLY MVFR VSBYS/CLGS WITH ANY TSTMS OR HEAVIER SHWRS FROM FRI
AFTN INTO ERLY SAT EVE.
&&
.MARINE...
NEAR TERM: NO HEADLINES WILL BE NEEDED TONIGHT OR THURSDAY. THE
MAIN CONCERN WILL BE REDUCED VISIBILITY IN SHOWERS AND FOG,
ESPECIALLY LATE TONIGHT.
SHORT TO LONG TERM: STILL NO DEFINITIVE HDLN PDS SLATED FOR THIS
PTN OF THE FCST. WENT WITH A BLEND OF 12Z NAM12/GFS40/GMOS THRU
SAT NGT AND MSLY 12Z GMOS WITH SOME 12Z GFS40 AND 06Z DGEX DATA
FOR WINDS. KEPT CLOSE TO WW3 FOR WVS OVR OUTER WATERS TAPERED TO
ABOUT HALF OUTER WATERS ALG THE IMMEDIATE COAST AND OVR INNER
HARBORS AND BAYS.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...HEWITT
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1230 AM CDT THU JUL 5 2012
.AVIATION...
SCATTERED THUNDERSTORMS WILL CONTINUE OVER SOUTHWEST NEBRASKA ALONG
A FRONTAL BOUNDARY FROM KIML TO KLBF TO KBBW THROUGH THE EARLY
MORNING HOURS. STRONG ERRATIC THUNDERSTORM WINDS CAN BE EXPECTED IN
THE VICINITY OF THUNDERSTORMS. WILL CARRY TSRA PREVAILING AT KLBF
TAF SITE THROUGH 0508Z. VISUAL FLIGHT RULES OVER WESTERN NEBRASKA ON
THURSDAY.
&&
.PREV DISCUSSION... /ISSUED 325 PM CDT WED JUL 4 2012/
DISCUSSION...
A COLD FRONT HAS BECOME STATIONARY FROM NEAR KOGA TO KTIF TO NEAR
KANW. THE FRONT IS EXPECTED TO BECOME THE FOCUS FOR ISOLATED TO
PERHAPS SCATTERED STRONG/SEVERE SLOW MOVING TSTMS LATE THIS AFTN
AND THIS EVENING. STORM DEVELOPMENT IS UNDERWAY. WEAKLY SHEARED
ENVIRONMENTAL WINDS AND DEEP VERTICAL MIXING SUGGEST THE
POTENTIAL FOR WIND DAMAGE AND HEAT BURSTS. THE HRRR INDICATES
PRECIPITABLE WATER NEAR OR ABOVE 1.5 INCHES SUPPORTING LOCALLY
HEAVY RAINFALL.
STORM ACTIVITY IS EXPECTED TO DEVELOP SOUTHEAST AND POSSIBLY
MERGE WITH ACTIVITY FCST TO SPREAD EAST THROUGH COLO AND INTO KS
LATE TONIGHT BEFORE DISSIPATING AFTER MIDNIGHT. THUS MOTHER NATURE
HAS ITS OWN FIRE WORKS SHOW PLANNED THIS EVENING AND VERY DRY AND
DUSTY CONDITIONS WILL SUPPORT STORMS CAPABLE OF DANGEROUS
LIGHTNING FOR ANYONE ATTENDING OUTDOOR EVENTS THIS EVENING.
THE STATIONARY FRONT IS EXPECTED TO LIFT NORTHWEST THURSDAY AND
THURSDAY NIGHT. TEMPERATURES ALONG AND SOUTH OF THE FRONT SHOULD
RISE INTO THE 100S ONCE AGAIN. NORTH OF THE FRONT ISOLATED TSTMS
MAY DEVELOP ACROSS NORTHWEST NEB ASSOCIATED WITH A PLUME OF
SUBTROPICAL MOISTURE AND WEAK PERTURBATIONS ROTATING NORTH AROUND
THE H500 MB RIDGE.
ANOTHER COLD FRONT WILL PUSH DOWN INTO THE FCST AREA FRIDAY
PRODUCING VERY WARM HIGHS SOUTH OF THE FRONT. THE NAM SUGGESTED
106 AT KONL AND THIS MIGHT NOT BE TOO FAR OFF THE MARK. FOR NOW
WILL FCST 104 AT KONL. NO PROBLEM WITH THE 102 FCST BY THE NAM AT
KLBF FOR FRIDAY. BASED ON THE TEMPERATURES THIS AFTN...105 AT KLBF
SO FAR...LATER FCSTS MAY HAVE TO MARK UP HIGHS FRIDAY. THE NAM AND
ECM ARE VERY DRY WITH THIS FRONT AND THE FCST FOLLOWS THE DRIER
SOLNS. THE HEAT ADVISORY HAS BEEN EXTENDED THROUGH FRIDAY.
THE UPPER LEVEL RIDGE CURRENTLY CENTERED OVER CNTL MISSOURI IS
FCST BUILD SLOWLY WEST FRIDAY THROUGH SUNDAY AND BE CENTERED OVER
UTAH BY MONDAY SETTING UP A NORTHWEST FLOW ALOFT THROUGHOUT THE
FCST AREA. THIS SHOULD HELP DRIVE A SIGNIFICANT COLD FRONT THROUGH
THE FCST AREA AND INTO KS FRIDAY FOR A SEMI PERMANENT COOL DOWN
LASTING SATURDAY THROUGH WEDNESDAY. HIGHS DURING THIS TIME PERIOD
SHOULD REMAIN NEAR NORMAL.
RAIN CHANCES ARE UNCERTAIN SUNDAY THROUGH WEDNESDAY BUT SEVERAL KEY
INGREDIENTS COULD CONSPIRE TO PRODUCE RAIN. THEY ARE UPSLOPE LOW
LEVEL MOISTURE FLOW...LOWER HEIGHTS ALOFT PRODUCING A WEAKER CAP
AND THE VERY UNCERTAIN POSSIBILITY OF DISTURBANCES DROPPING
SOUTHEAST OUT OF THE NRN PLAINS PRODUCING ISOLATED TO SCATTERED
STORM COVERAGE DAILY. THE GENERAL CONSENSUS BETWEEN THE ECM AND
GFS SUGGESTED THE BEST CHANCE OF RAIN WOULD GENERALLY BE ALONG
AND WEST OF HIGHWAY 61.
&&
.CLIMATE...
THIS IS THE THIRD DAY IN A ROW OF 100 PLUS TEMPERATURES AT NORTH
PLATTE. THIS STREAK IS FORECAST TO CONTINUE THROUGH FRIDAY WHICH
WOULD RIVAL THE GREAT HEAT WAVES OF 1934 (13 DAYS)...1935 (5
DAYS)...1936 (6 DAYS) AND 1955 (5 DAYS).
&&
.LBF WATCHES/WARNINGS/ADVISORIES...HEAT ADVISORY UNTIL 9 PM CDT
FRIDAY FOR NEZ005>010-025>029-037-038-059-070-071.
&&
$$
SHORT TERM/EXTENDED...CDC
AVIATION...MASEK
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1203 AM CDT THU JUL 5 2012
.DISCUSSION...LATEST REGIONAL RADAR SHOWS ECHOES INCREASING OVER
SOUTHEAST MONTANA. THE LATEST HRRR MODEL TAKES THIS AREA AND MOVES
IT INTO OUR SOUTHWEST COUNTIES THROUGH 12Z. COMPARING THE 1KM AGL
REFLECTIVITY AND COMPOSITE REFLECTIVITY...IT APPEARS THAT ANY
ACTIVITY WOULD EITHER BE VERY LIGHT/SPRINKLES OR A BRIEF SHOWER.
THE GFS SHOWS SOME INDICATION OF THIS INTO OUR SOUTHWEST BY 12Z
WHILE THE NAM KEEPS IT IN SOUTHEAST MONTANA. HAVE ADDED IN 20 POPS
FOR NOW IN THE SOUTHWEST THROUGH 12Z THURSDAY.
ATTENTION TURNS TOWARD THURSDAY NIGHT INTO FRIDAY MORNING. LATEST
00Z DATA/SOUNDINGS INDICATIVE OF MAINLY HEAVY RAIN...BUT
REMAINING BELOW THE 1HR/3HR/6HR FLASH FLOOD GUIDANCE. THE BEST
SEVERE THREAT FOR LARGE HAIL AND DAMAGING WINDS LOOK TO REMAIN
SOUTH OF OUR CWA...BUT ONE TO TWO INCHES OF RAINFALL SHOULD BE
WIDESPREAD OVER SOUTHERN NORTH DAKOTA THROUGH FRIDAY MORNING.
&&
.AVIATION...VFR CONDITIONS WILL PREVAIL ACROSS WESTERN AND CENTRAL
NORTH DAKOTA THROUGH THURSDAY AFTERNOON. CHANCES FOR THUNDERSTORMS
AND ASSOCIATED TEMPO MVFR/IFR CONDITIONS WILL INCREASE FROM SOUTHWEST
(KDIK) AROUND 00Z TO SOUTH CENTRAL (KBIS) AROUND 03Z FRIDAY. THE
HEAVIEST ACTIVITY IS EXPECTED TO REMAIN ACROSS CENTRAL AND SOUTHERN
NORTH DAKOTA AND WILL LIKELY AFFECT KJMS AFTER 06Z FRIDAY. FOR NOW
INDICATED VCTS IN THE KDIK/KBIS TAFS GIVEN THE TIMING UNCERTAINTY.
LATER TAF ISSUANCES SHOULD HAVE GREATER DETAIL.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
DISCUSSION...KS
AVIATION...TM
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
355 AM CDT THU JUL 5 2012
.SHORT TERM...TODAY THROUGH SATURDAY NIGHT
354 AM CDT THU JUL 5 2012
AT 3 AM...THE MESOSCALE CONVECTIVE COMPLEX...WHICH WAS RESPONSIBLE
FOR THE SEVERE WEATHER LAST EVENING ACROSS DULUTH/S FORECAST AREA...
CONTINUES TO WEAKEN AS THE UPPER LEVEL FORCING MOVES AWAY FROM THE
AREA. MEANWHILE IN THE PAST HOUR...A CLUSTER OF SHOWERS AND
THUNDERSTORMS HAS DEVELOPED FROM SOUTHWEST MINNESOTA SOUTHEAST
INTO CENTRAL IOWA. THIS PRECIPITATION IS DEVELOPING ON THE NOSE OF
A 30 TO 40 KNOT 850 MB JET. THIS JET MAY BE IMPINGING ON SOME
ELEVATED OUTFLOW BOUNDARY FROM THE CONVECTION OVER NEBRASKA. IN
ADDITION...THERE IS ALSO A 700 MB TROUGH FROM NORTHWEST MINNESOTA
SOUTHEAST INTO SOUTHWEST MINNESOTA. WHILE THERE IS INSTABILITY
/1-2K MOST UNSTABLE CAPES/ IN THIS AREA...THE 1-6 KM SHEAR IS NOT
THAT IMPRESSIVE AT ALL...SO NOT EXPECTING THESE STORMS TO BECOME
ORGANIZED. THEREFORE ONLY EXPECTING ELEVATED PULSE STORMS. WITH
THE DCAPE RUNNING UP TO 1500 J/KG...THERE WILL BE THE POTENTIAL
FOR SOME ISOLATED DAMAGING WIND GUSTS WITH A FEW OF THESE STORMS.
AS THE TROUGH MOVES AWAY FROM THE REGION AND THE LOW LEVEL JET
WANES TOWARD SUNRISE...EXPECT THAT THESE THUNDERSTORMS WILL WEAKEN
AND DISSIPATE BY 05.15Z.
FOR THIS AFTERNOON AND EVENING...THE COLD FRONT /THAT TERM IS BEING
USED VERY LIBERALLY BECAUSE THERE IS JUST A WIND SHIFT ASSOCIATED
WITH IT/ WILL MOVE AS FAR SOUTH AS THE MINNESOTA BORDER AND THEN
STALL. MEANWHILE ALOFT THE 05.00Z MODELS ARE IN VERY GOOD
AGREEMENT THAT THE UPPER LEVEL RIDGE WILL BE BUILDING NORTHWARD
INTO THE AREA. THIS SHOULD RESULT IN SUBSIDENCE ALOFT. IN
ADDITION...THERE WILL BE 700 MB CAP RUNNING BETWEEN 10 AND
14C...LITTLE /IF ANY/ MOISTURE CONVERGENCE ALOFT...AND NO SYSTEM
ALOFT TO WEAKEN THE CAPPING ALOFT. AS A RESULT...NOT IMPRESSED AT
ALL WITH THE CHANCES OF PRECIPITATION FOR THIS TIME PERIOD. IF ANY
CONVECTION DID DEVELOP...THE SHEAR IS VERY WEAK...SO AT MOST YOU
WOULD GET IS A PULSE SEVERE STORM. WITH THIS SAID...THE ARW DOES
GENERATE SUPERCELL SHEAR FOR LATE THIS AFTERNOON. THIS LOOKS TO BE
CAUSED BY ITS EXPLOSIVE CONVECTIVE INITIATION...SO DISCOUNTING
THAT THIS IS REAL. THE AIR MASS HAS CHANGED LITTLE ALOFT FROM
YESTERDAY...SO EXPECT TO SEE TEMPERATURES SIMILAR TO YESTERDAY.
WITH THIS SAID...WILL HAVE TO WATCH HOW MUCH CLOUD COVER LINGERS
FROM THE CONVECTIVE COMPLEX TO OUR WEST.
FROM TONIGHT INTO FRIDAY EVENING...A MAJORITY OF THE MODELS SUGGEST
THAT AS THE LOW PRESSURE SYSTEM DEVELOPS ACROSS SOUTH DAKOTA
TONIGHT THAT THE FRONT WILL QUICKLY PUSH NORTH AS A WARM FRONT.
IN THE WARM SECTOR OF THIS SYSTEM...THERE WILL BE A GOOD CAP IN
PLACE...SO THINKING THAT THE AREA SHOULD REMAIN DRY. THERE IS ALSO
VERY LITTLE 0-6 KM SHEAR. WITH THIS IN MIND...THE SPC DAY 2
OUTLOOK APPEARS TO BE AT LEAST 150 MILES TOO FAR SOUTH. ONE THING
NEW FOR FRIDAY IS THAT WE WILL ACTUALLY SEE SOME WINDS ALOFT TO
AID WITH THE MIXING OF THE WARM AIR FROM ALOFT...THEREFORE...WE
COULD ONCE AGAIN SEE TEMPERATURES AROUND 100 DEGREES.
FROM FRIDAY NIGHT THROUGH SATURDAY NIGHT...THE MODELS SHOW THAT
THE COLD FRONT WILL MOVE SOUTH THROUGH THE AREA. AS THIS OCCURS...
OUR TEMPERATURES WILL RETURN TO WHAT WE WOULD TYPICALLY SEE THIS
TIME OF YEAR. BOTH THE GFS AND NAM/WRF ARE THE FASTEST AT MOVING
THIS FRONT THROUGH THE AREA. MEANWHILE THE ECMWF IS MUCH SLOWER AT
PUSHING THIS FRONT THROUGH THE REGION. THE NAM/WRF AND GFS WOULD
SUGGEST THAT SATURDAY NIGHT WILL BE DRY. MEANWHILE THE ECMWF WOULD
CONTINUE A CHANCE OF PRECIPITATION FOR THIS ENTIRE TIME PERIOD.
WITH LIMITED MOISTURE TRANSPORT AND CONVERGENCE ALONG THIS
FRONT AND THE MAIN SHORT WAVE MOVING AWAY FROM THE REGION...NOT
IMPRESSED WITH RAIN CHANCES ALONG AND SOUTH OF THE INTERSTATE 90
CORRIDOR.
.LONG TERM...SUNDAY THROUGH WEDNESDAY
354 AM CDT THU JUL 5 2012
ON SUNDAY...THERE IS STILL SOME QUESTION ON WHERE THE FRONT WILL
BE LOCATED. THE NAM/WRF AND GFS WOULD HAVE THE FRONT WELL SOUTH OF
THE AREA. MEANWHILE THE ECMWF WOULD SUGGEST THAT THERE WOULD STILL
BE SOME SCATTERED CONVECTION LOCATED ACROSS THE REGION. SINCE IT
IS UNCLEAR WHICH MODEL IS CORRECT...JUST WENT WITH A 20 PERCENT
CHANCE OF RAIN.
FOR THE REMAINDER OF THIS FORECAST PERIOD...IT LOOKS LIKE A
CANADIAN HIGH WILL PROVIDE SEASONABLE TEMPERATURES AND DRY
CONDITIONS.
&&
.AVIATION...THROUGH 06Z FRIDAY
1141 PM CDT WED JUL 4 2012
THE SURFACE BOUNDARY HAS SLIPPED A LITTLE TO THE SOUTH THIS
EVENING ACROSS NORTHWEST INTO EASTERN WISCONSIN. A THUNDERSTORM
COMPLEX CONTINUES NORTH OF THE BOUNDARY OVER NORTHEAST MINNESOTA.
FORWARD PROPAGATING CORFIDI VECTORS SUGGEST THIS COMPLEX SHOULD
MOVE SOUTHEAST ALONG THE BOUNDARY TOWARD CENTRAL WISCONSIN MISSING
BOTH TAF SITES. NOT SURE HOW FAR THE COMPLEX WILL MAKE IT BEFORE
IT STARTS TO WEAKEN AS THE 05.03Z RAP SHOWS THE SUPPORTING SHORT
WAVE TROUGH MOVES ALMOST STRAIGHT EAST ACROSS LAKE SUPERIOR INTO
ONTARIO. SO AS THE COMPLEX MOVES SOUTHEAST...IT WILL GET FARTHER
AWAY FROM ITS SUPPORT AND THE LOW LEVEL JET IS NOT OVERLY
STRONG...AROUND 25 KNOTS...TO FEED MOISTURE AND INSTABILITY INTO
THE COMPLEX. THIS COMPLEX SHOULD SERVE TO PUSH THE BOUNDARY/WIND
SHIFT FARTHER SOUTH AND THIS MAY MAKE IT INTO THE REGION THURSDAY
AFTERNOON. WILL SHOW A WIND SHIFT TO THE NORTHWEST AT KRST DURING
THE MID AFTERNOON. ABOUT THE TIME THE WIND SHIFT SHOULD BE
APPROACHING KLSE...THE WINDS WILL BE DECOUPLING SO JUST WENT WITH
VARIABLE WINDS FOR THE EVENING. LITTLE TO NO CLOUDS EXPECTED AND
VFR CONDITIONS SHOULD PREVAIL.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
354 AM CDT THU JUL 5 2012
WI...EXCESSIVE HEAT WARNING UNTIL 10 PM CDT FRIDAY FOR WIZ017-029-
032>034-041>044-053>055-061.
MN...EXCESSIVE HEAT WARNING UNTIL 10 PM CDT FRIDAY FOR MNZ079-086>088-
094>096.
IA...EXCESSIVE HEAT WARNING UNTIL 10 PM CDT FRIDAY FOR IAZ008>011-018-
019-029-030.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1141 PM CDT WED JUL 4 2012
.SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT
321 PM CDT WED JUL 4 2012
MAIN FORECAST CONCERNS THIS PACKAGE...CONTINUED EXCESSIVE HEAT
THROUGH FRIDAY...SHRA/TSRA CHANCES THROUGH THE PERIOD.
18Z DATA ANALYSIS HAD A WEAK AREA OF LOW PRESSURE IN SOUTHEAST ND
WITH A WARM FRONT EAST INTO NORTHERN WI AND A COLD FRONT SOUTHWEST
TO ANOTHER LOW IN EASTERN CO. A VERY WARM/HOT AIRMASS IN PLACE
ACROSS MN/IA/WI SOUTH OF THE WARM FRONT AND AHEAD OF THE COLD FRONT
WITH 1 PM ALREADY IN THE 90S TO NEAR 100 AND HEAT INDICES THE 95 TO
110 RANGE. STRONGEST OF MOISTURE TRANSPORT/THETA-E CONVERGENCE
ACROSS THE REGION EARLY THIS AFTERNOON WAS FOCUSED INTO NORTHERN
MN...WHERE A CONVECTIVE COMPLEX THAT ORIGINATED IN THE SOUTHEAST
CORNER OF SASKAT TUE EVENING CONTINUED TO PROPAGATE EAST/SOUTHEAST
INTO THE MOISTURE/INSTABILITY AXIS NEAR/JUST NORTH OF THE WARM
FRONT.
04.12Z LOOK TO HAVE INITIALIZED WELL...BUT FOR GFS AND ITS 2-7F HIGH
BIAS ON SFC DEW POINTS OVER PORTIONS OF THE MID/UPPER MS VALLEY.
SOLUTIONS RATHER SIMILAR FOR TONIGHT/MUCH OF THU...BUT ALREADY
DIVERGE WITH THE TIMING/LOCATION OF THE COLD FRONTAL PASSAGE LATE
THU/THU NIGHT. MODELS THEN DIFFER ON THE EVOLUTION/TIMING OF THE LOW
LIFTING OUT OF THE PLAINS AND ALONG THE FRONT FOR FRI INTO SAT
NIGHT. DPROG/DT OF 500MB HGTS AT 04.12Z SHOWED MODEL RUNS OF 02.12Z
AND 03.12Z VERIFIED WELL ACROSS NOAM/EASTERN PAC...FAVORING MORE
PROGRESSIVE OF EARLIER RUNS. GFS WITH THE BETTER RUN-TO-RUN
CONSISTENCY. MODELS CONVERGING ON A TIGHTER CONSENSUS TONIGHT
THRU THU NIGHT...FAVORING A COMPROMISE OF THE EARLIER RUNS. MODELS
REMAIN IN GOOD SYNOPTIC SCALE AGREEMENT FOR FRI INTO SAT NIGHT BUT
DIFFER ON THE TIMING/STRENGTH DETAILS OF SHORTWAVES TOPPING/
FLATTENING THE MID CONUS RIDGING. CHECK OF OBS VS. MODEL DATA AT 18Z
SHOWED ALL REASONABLE WITH THE CENTRAL NOAM SFC PRESSURE FIELD. ALL
STRUGGLING A BIT WITH THE HIGHER DEWPOINTS/MOISTURE POOLING OVER
THE UPPER MIDWEST. ALL MODELS HAVING DIFFICULTY WITH THE NORTHERN MN
CONVECTIVE COMPLEX. GFS AND 04.12 NMM/ARW WRF MODELS LOOK BEST WITH
THE COMPLEX...BUT SUFFER FROM PRECIP/CONVECTION ISSUES ELSEWHERE
ACROSS THE REGION. THUS NO ONE MODEL FAVORED FOR ANY CONVECTIVE
DETAILS THIS CYCLE. PREFER THE MODEL/ENSEMBLE CONSENSUS THIS CYCLE
AND FAVORED LARGER SCALE FORCING MECHANISMS FOR SHRA/TSRA CHANCES
THE NEXT FEW DAYS. GIVEN ALL THE DETAIL DIFFERENCES...SHORT-TERM
FCST CONFIDENCE AVERAGE THIS CYCLE.
IN THE SHORT TERM...NORTHERN MN CONVECTION LOOKS LIKE IT WILL
CONTINUE TO PROPAGATE EAST/SOUTHEAST...NORTH OF THE WARM FRONT AND
PERHAPS CLIP INTO FAR NORTHERN WI THIS EVENING. LAPS SOUNDINGS SHOW
AIRMASS OVER THE FCST AREA MIXED TO 850-800MB WITH MINIMAL CAPPING.
HOWEVER LITTLE IF ANY CUMULUS WITH TEMP-DEWPOINT SPREADS IN THE 25-
30F RANGE. SOUNDINGS WOULD HAVE TO MIX TO 750-700MB FOR CUMULUS...
BUT FOR FAR NORTH END OF THE FCST AREA. WILL LEAVE THIS EVENING DRY
WITH LITTLE IN THE WAY OF FORCING/LIFT OVER/AROUND THE AREA. MAIN
LOW IN CANADA TRACKS TO HUDSONS BAY BY LATE THU...DRAGGING THE COLD
FRONT TO NEAR A KIWD-KMSP-KSUX LINE BY 12Z THU THEN TO NEAR A KGRB-
KLSE-KOMA LINE BY 00Z FRI. A FEW OF THE WRF MODELS AND GFS INITIATE
CONVECTION ALONG THE FRONT TONIGHT...MOVING INTO THE NORTHWEST END
OF THE FCST AREA FOR LATER TONIGHT/THU MORNING. NOT A LOT OF
CONFIDENCE IN ANY OF THE FORCING DETAILS BUT CARRIED A SMALL SHRA/
TSRA CHANCE ROUGHLY NORTH OF A KRST-BLACK RIVER FALLS LINE LATE
TONIGHT/THU MORNING FOR THE POSSIBILITY. WITH STEEP LOW/MID LEVEL
LAPSE RATES...MINIMAL CAPPING SIMILAR TO TODAY WITH THE EXTREME HEAT
AND DEW POINTS/CAPE AXIS POOLED NEAR THE COLD FRONT OOZING SOUTH
THRU THE AREA...ADDED AT LEAST A 20 PERCENT TSRA CHANCE TO THU
AFTERNOON. CONTINUED THIS SMALL CHANCE FOR THE CENTRAL/SOUTH PARTS
OF THE FCST ARE THU EVENING.
ANOTHER SCORCHER ON THU WITH NEAR RECORD OR RECORD HIGHS. 850MB
TEMPS AGAIN IN THE +24 TO +26C RANGE...ABOUT A DEGREE WARMER THAN
THOSE OF TODAY. DEW POINTS THU REMAIN IN THE UPPER 60S TO MID 70S...
PERHAPS HIGHER WITH THE MOISTURE POOLED NEAR THE FRONT MOVING SOUTH
INTO THE AREA. EXCESSIVE HEAT WARNING REMAINS IN PLACE THRU AT LEAST
THU NIGHT. WITH GOOD CONSENSUS FOR THE FRONT TO BE SOUTH OF THE AREA
FRI AND SOME COOLER/DRIER AIR FILTERING IN FROM THE NORTH...MAY BE
ABLE TO TRIM COUNTIES FROM WABASHA TO JACKSON AND NORTH OUT OF THE
HEAT WARNING FOR FRI. WILL NOT DO THIS NOW DUE TO MODEL DETAIL
DIFFERENCES ON FRONT LOCATION AND HOW QUICKLY SLIGHTLY DRIER AIR
MOVES SOUTH BEHIND IT.
LEFT MOST OF THE SHRA/TSRA CHANCES FOR FRI THRU SAT NIGHT...NEAR OR
NORTH OF THE FRONTAL BOUNDARY...IN THE 20-50 PERCENT RANGE. THE
DETAIL DIFFERENCES OF SHORTWAVE ENERGY ROTATING AROUND THE TOP OF
THE RIDGE AXIS...HOW THE CENTRAL PLAINS SFC LOW LIFTS/TRACKS
EAST/NORTHEAST ALONG THE FRONT...IF THE FRONT LIFTS BACK NORTH...AND
WHEN/WHERE THE STRONGER OF THE 925-850MB MOISTURE TRANSPORT/THETA-E
CONVERGENCE WOULD FOCUS...ALL PROVIDE FOR VARYING SOLUTIONS FOR RAIN
CHANCES/AMOUNTS ACROSS THE FCST AREA FOR THIS PERIOD. THUS FAVORED
THE MODEL CONSENSUS FOR RAIN CHANCES FRI THRU SAT NIGHT. MORE
CLOUDS EXPECTED FOR SAT AND POTENTIAL FOR SHRA/TSRA WILL PROVIDE
SOME RELIEF FROM THE HEAT FOR THE WEEKEND.
GENERALLY FAVORED WARMER OF GUIDANCE LOWS/HIGHS FOR TONIGHT THRU
FRI WITH THE WARM 925-850MB AIRMASS OVER THE AREA. WITH A BIT MORE
UNCERTAINTY WITH THE FRONT/CLOUDS/CONVECTION...FAVORED A BLEND OF
THE NUMERICAL GUIDANCE LOWS/HIGHS FOR FRI NIGHT THRU SAT NIGHT.
.LONG TERM...SUNDAY THROUGH WEDNESDAY
321 PM CDT WED JUL 4 2012
04.00Z AND 04.12Z MEDIUM RANGE MODEL RUNS IN GOOD AGREEMENT SUN/MON
FOR RIDGING ALOFT TO REBUILD OVER WESTERN NOAM AND THE UPPER MIDWEST
TO COME UNDER INCREASING NORTHWEST FLOW ALOFT. CONTINUED GOOD
AGREEMENT FOR THE REGION TO REMAIN UNDER NORTHWEST FLOW ALOFT
TUE/WED WITH SOME DECREASING AMPLITUDE OF THE WESTERN NOAM RIDGING.
NO MODEL WITH CLEARLY BETTER RUN-TO-RUN CONSISTENCY /AT LEAST AT
500MB/ IN THE DAY 4-7 PERIOD. WITH BETTER BETWEEN MODEL CONSISTENCY
THE LONG-TERM FCST CONFIDENCE IS AVERAGE TO GOOD THIS CYCLE. SOME
DIFFERENCES OF TIMING OF THE LAST OF THE SHORTWAVES AND 850-700MB
MOISTURE TRANSPORT NORTH OF THE FRONTAL BOUNDARY TO PASS SOUTH OF
THE AREA SUN...ECMWF SLOWER...GFS/GEM FASTER EXITING THIS
FORCING/LIFT. SMALL SHRA/TSRA CHANCE ON SUN LOOKS GOOD FOR NOW.
AFTER THAT...COOLER/DRIER CAN HIGH PRESSURE LOOKS TO SETTLE SOUTH
ACROSS THE UPPER MIDWEST FOR MON-WED. WITH THE SFC HIGH PRESSURE AND
NORTHWEST FLOW ALOFT...GFS LOOKS TO HANG ONTO TOO MUCH LOWER LEVEL
MOISTURE BY TUE/WED...AND GENERATES INSTABILITY/PRECIP ON DAYS 6/7.
SOME LESSER CONFIDENCE ON THE SHRA/TSRA CHANCES BY TUE/WED BUT SIDED
WITH THE NON-GFS MODEL/ ENSEMBLE CONSENSUS FOR NOW. BETTER
CONFIDENCE FOR SUN-WED TEMPS TO BE CLOSER TO EARLY JULY NORMALS.
&&
.AVIATION...THROUGH 06Z FRIDAY
1141 PM CDT WED JUL 4 2012
THE SURFACE BOUNDARY HAS SLIPPED A LITTLE TO THE SOUTH THIS
EVENING ACROSS NORTHWEST INTO EASTERN WISCONSIN. A THUNDERSTORM
COMPLEX CONTINUES NORTH OF THE BOUNDARY OVER NORTHEAST MINNESOTA.
FORWARD PROPAGATING CORFIDI VECTORS SUGGEST THIS COMPLEX SHOULD
MOVE SOUTHEAST ALONG THE BOUNDARY TOWARD CENTRAL WISCONSIN MISSING
BOTH TAF SITES. NOT SURE HOW FAR THE COMPLEX WILL MAKE IT BEFORE
IT STARTS TO WEAKEN AS THE 05.03Z RAP SHOWS THE SUPPORTING SHORT
WAVE TROUGH MOVES ALMOST STRAIGHT EAST ACROSS LAKE SUPERIOR INTO
ONTARIO. SO AS THE COMPLEX MOVES SOUTHEAST...IT WILL GET FARTHER
AWAY FROM ITS SUPPORT AND THE LOW LEVEL JET IS NOT OVERLY
STRONG...AROUND 25 KNOTS...TO FEED MOISTURE AND INSTABILITY INTO
THE COMPLEX. THIS COMPLEX SHOULD SERVE TO PUSH THE BOUNDARY/WIND
SHIFT FARTHER SOUTH AND THIS MAY MAKE IT INTO THE REGION THURSDAY
AFTERNOON. WILL SHOW A WIND SHIFT TO THE NORTHWEST AT KRST DURING
THE MID AFTERNOON. ABOUT THE TIME THE WIND SHIFT SHOULD BE
APPROACHING KLSE...THE WINDS WILL BE DECOUPLING SO JUST WENT WITH
VARIABLE WINDS FOR THE EVENING. LITTLE TO NO CLOUDS EXPECTED AND
VFR CONDITIONS SHOULD PREVAIL.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
321 PM CDT WED JUL 4 2012
WI...EXCESSIVE HEAT WARNING UNTIL 10 PM CDT FRIDAY FOR WIZ017-029-
032>034-041>044-053>055-061.
MN...EXCESSIVE HEAT WARNING UNTIL 10 PM CDT FRIDAY FOR MNZ079-
086>088-094>096.
IA...EXCESSIVE HEAT WARNING UNTIL 10 PM CDT FRIDAY FOR IAZ008>011-
018-019-029-030.
&&
$$
SHORT TERM...RRS
LONG TERM....RRS
AVIATION...04
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
614 AM CDT THU JUL 5 2012
.AVIATION...
UPPER LEVEL RIDGE TO KEEP WX RELATIVELY QUIET THROUGH 12Z ON THE
6TH. WEAK...ISOLATED SHOWERS/THUNDERSTORMS CURRENTLY AFFECTING
PORTIONS OF NORTH CENTRAL AND NORTHEAST IOWA. THESE ARE IN A
DECAYING MODE AT THE MOMENT AND ARE EXPECTED TO STAY AWAY FROM
KCID AND KDBQ...THOUGH THEY MAY DRIFT INTO THE VICINITY...AND AND
UPDATE TO TERMINAL FORECAST FOR THESE LOCATIONS MAY BE NEEDED. FOR
NOW THOUGH...DRY FORECAST WITH JUST SCATTERED HIGH ALTOCUMULUS.
THESE SHOULD DISSIPATE BY MID MORNING. THIS AFTERNOON ADDITIONAL
SHOWERS/THUNDERSTORMS ARE POSSIBLE...BUT UNCERTAINTY VERY HIGH AND
HAVE LEFT THESE OUT OF FORECAST FOR NOW AS WELL. OTHERWISE...VFR
CONDITIONS EXPECTED. LIGHT SOUTHWEST WINDS SHOULD INCREASE TO
10-12KTS FOR TODAY...THEN DIMINISH TO LESS THAN 10 KTS OVERNIGHT
TONIGHT. LE
&&
.PREV DISCUSSION... /ISSUED 339 AM CDT THU JUL 5 2012/
SYNOPSIS...
ANOTHER VERY WARM NIGHT WITH MUGGY CONDITIONS. TEMPERATURES STILL
HOVERING IN THE MID TO UPPER 70S WITH DEWPOINTS IN THE MID 60S TO
AROUND 70S. SOME INTERESTING THINGS GOING ON OUT THERE TONIGHT. A
COLD FRONT IS APPROACHING IOWA FROM THE NORTHWEST...THAT AS OF A
MIDNIGHT ANALYSIS WAS DRAPED FROM NORTHERN MINNESOTA ACROSS
SOUTHEAST SOUTH DAKOTA...THEN BACK WEST ACROSS NEBRASKA TO NORTHEAST
COLORADO. A VERY NICE LOW LEVEL JET HAS FORMED FROM OKLAHOMA UP
INTO WESTERN IOWA. THIS WAS FEEDING AN MCS UP IN CENTRAL
MINNESOTA...BUT NOW THAT IT HAS MOVED EAST OUT OF THE LOW LEVEL
JET...IT HAS FALLEN APART. INSTEAD...NEW CONVECTION HAS FIRED IN
SOUTHWEST MINNESOTA...AND ADDITIONAL CONVECTION SEEMS TO BE
INITIATING IN NORTHWEST IOWA AND EVEN NORTH CENTRAL IOWA AS OF 3
AM. THERE IS LITTLE IF ANY SURFACE BOUNDARY THAT THIS COULD HAVE
FOCUSED ON...BUT THERE IS A NICE SURGE OF 850MB WAA AND DEEP MOISTURE
CONVERGENCE IN THIS AREA ACCORDING TO THE SPC RAP MESOSCALE ANALYSIS
THAT IT COULD BE FOCUSED ON.
LE
SHORT TERM...TODAY AND TONIGHT...
MAIN CONCERN FOR TODAY IS FOR CONVECTIVE TRENDS AND OF COURSE...
TEMPERATURES AND DEWPOINTS. THIS MORNINGS CONVECTION OVER CENTRAL
IOWA IS UNLIKELY TO BE ABLE TO PROPAGATE VERY FAR EAST BEFORE IT
MOVES OUT OF ITS MOISTURE FEED AND DISSIPATES. THE RAP MODEL IS
DEPICTING THIS FAIRLY WELL...AND IT SEEMS TO ONLY PULL IT INTO THE
NORTH WESTERN PORTIONS OF THE FORECAST AREA BEFORE IT FALLS APART.
HAVE DECIDED TO INCREASE POPS IN THIS REGION FOR A FEW HOURS THIS
MORNING...BUT THEN LOWER AGAIN FOR THE REMAINDER OF THE MORNING
HOURS. OTHER MODELS ALSO WANT TO POP SOME ISOLATED CONVECTION
ACROSS ABOUT THE NORTHERN HALF OF THE FORECAST AREA DURING THE DAY
TODAY...PERHAPS IN A SIMILAR MODE OF INITIATION. AM NOT TERRIBLY
EXCITED ABOUT THIS AS THE CAP COMES INTO PLAY LATER IN THE DAY AS
MORE HOT DRY AIR IS ADVECTED INTO THE AREA AT 700MB. THUS...HAVE
KEPT POPS TO ISOLATED OR SLIGHT CHANCE AT BEST FOR THE LATE MORNING
AND AFTERNOON HOURS. THIS IS GOING TO INCREASE CLOUDS OVER THE AREA
TODAY...EVEN IF IT IS ONLY SOME CIRRUS BLOWN OFF WESTERN
CONVECTION. THIS WILL ACT TO LIMIT HEATING SOMEWHAT...BUT WITH THE
MIXING AND DRY GROUND STILL FEEL LIKE WE WILL GET WELL INTO THE
UPPER 90S AND TO AROUND 100 TODAY. MAY END UP HAVING TO LOWER HIGH
TEMPS IN ACROSS THE NORTH IF THIS CONVECTION ENDS UP BEING MORE
WIDESPREAD THAN ANTICIPATED...BUT THIS SEEMS UNLIKELY AT THIS TIME.
DEWPOINTS HAVE BEEN A REAL BEAR TO FORECAST LATELY...AND WITH THE
LARGE IMPACT THEY HAVE ON HEAT INDEX VALUES...THEY HAVE BEEN
CRITICAL. TODAY AM USING A LOT OF PERSISTENCE FROM YESTERDAYS
FORECAST...BUT FEEL THAT WITH CONVERGENCE INCREASING AHEAD OF THE
APPROACHING BOUNDARY THIS MAY ACT TO HOLD THEM UP EVEN AS WE GET
SLIGHTLY DEEPER MIXING TODAY. CORN CROP HAS ALSO BEEN ACTING TO
HOLD THEM UP IN RECENT DAYS...BUT WE ARE GETTING FARTHER AWAY FROM
THE MOST RECENT RAINFALL...AND THIS EFFECT MAY TAIL OFF SOMEWHAT.
THUS...AM CONTINUING THE EXCESSIVE HEAT WARNING TODAY AS THE HEAT
INDEX VALUES SHOULD BE IN THE 105-110 RANGE FOR A FAIRLY LARGE
PORTION OF THE AREA. THE FAR SOUTH HAS ESCAPED THIS LATELY AS THE
DEWPOINTS HAVE BEEN MIXING DOWN INTO THE UPPER 60S...BUT TODAY THE
EXTRA HEAT SHOULD EASE THEM OVER THE 105 MARK FOR THE FIRST TIME.
ALSO...WE ARE ON OUR 3RD DAY OF AT LEAST 100 DEGREE HEAT INDEX
VALUES...AND THIS IS GOING TO HAVE A DETRIMENTAL AFFECT ON PEOPLE.
TONIGHT WILL BE ANOTHER VERY WARM AND MUGGY NIGHT AND WITH THE
BOUNDARY JUST NORTH OF THE AREA. HAVE KEPT POPS OUT OF THE AREA FOR
NOW...BUT THIS AFTERNOONS CONVECTIVE TRENDS ARE GOING TO BE KEY FOR
DETERMINING WHAT GOES ON TONIGHT. HOWEVER...THE BETTER MID LEVEL
CONVERGENCE WILL BE FOCUSED OUT WEST ACROSS THE NEBRASKA/SOUTH
DAKOTA REGION AGAIN...WHICH WOULD HAVE TO DRIFT EAST INTO OUR AREA
BEFORE DECAYING. IT IS UNLIKELY TO BE ABLE TO GET THIS FAR BEFORE
IT FALLS APART. MIN TEMPS TO ONLY BE IN THE MID TO UPPER 70S.
LE
LONG TERM...FRIDAY THROUGH WEDNESDAY...
FORECAST FOCUS ON HOT AND HUMID FRIDAY AND SATURDAY THEN COOLER WITH
COMFORTABLE HUMIDITY FOR MOST OF NEXT WEEK. BY THE MIDDLE OF JULY
THE RIDGE BUILDS AGAIN RETURNING HOT WEATHER TO THE MIDWEST. FOR AT
LEAST THE NEXT 10 DAYS THE ONLY CHANCE OF RAIN WILL BE WITH THE COLD
FRONT SUNDAY OR SUNDAY NIGHT BUT EVEN THIS IS STARTING TO LOOK BLEAK.
FRIDAY AND SATURDAY...HOT AND HUMID TO CONTINUE INTO SATURDAY WITH
FRIDAY LOOKING TO BE A REAL SCORCHER. WILL HAVE WIDESPREAD MAX TEMPS
ON FRIDAY OF AROUND 100 WITH HEAT INDEX VALUES OF AT LEAST 110.
EXCESSIVE HEAT WARNING WILL REMAIN IN PLACE. OF COURSE THIS ASSUMES
FULL SUNSHINE AND NO CLOUD DEBRIS FROM ANY MCS THAT MAY OCCUR TO OUR
NORTH. ANY CLOUDS WOULD KEEP THE VERY HOT TEMPERATURES FROM BEING
REALIZED. THE CONSENSUS IS THEN TO START BRINGING A WEAK COLD FRONT
INTO THE NORTHERN CWA SOMETIME ON SATURDAY. THIS SHOULD BRING A
SLIGHT CHANCE OF STORMS AND MORE CLOUDS LATER IN THE DAY. MAX TEMPS
SHOULD BE STILL HOT BUT NOT AS BAD AS FRIDAY. WILL CONTINUE WITH
AFTERNOON READINGS RANGING FROM 90 ALONG HIGHWAY 20 TO AROUND 100
FROM HIGHWAY 34 SOUTHWARD. HEAT INDEX VALUES SHOULD BE IN THE 100 TO
105 RANGE. THIS MAY REQUIRE A HEAT ADVISORY INSTEAD OF A WARNING FOR
SATURDAY FOR ALL OR A PORTION OF THE CWA. THIS WILL DEPEND ON THE
TIMING OF THE ARRIVING FRONT.
SATURDAY NIGHT THROUGH SUNDAY NIGHT...COVERAGE OF STORMS WILL DEPEND
ON THE TIMING OF THE COLD FRONT. THE GFS HAS BEEN ERRONEOUSLY
DEPICTING LARGE AREAS OF QPF LATELY AND HAS BEEN IGNORED. BUT BASED
ON WHAT IS CURRENTLY HAPPENING THE ECM IS TOO DRY. THE ECM SUGGESTS
THE FRONT MAY ARRIVE SUNDAY MORNING WHICH WOULD BE NOT FAVORABLE FOR
THUNDERSTORMS. SHEAR IS VERY WEAK AND THE THREAT FOR STRONG STORMS
SEEM TO BE DIMINISHING. MAX TEMPS ON SUNDAY WILL BE COOLER WITH MOST
AREAS IN THE 80S TO NEAR 90. WILL HAVE SMALL POPS FOR THE WEEKEND.
THE BAD NEWS IS IF YOU MISS OUT ON THIS RAIN OPPORTUNITY THE MODELS
SUGGEST AN EXTENDED DRY PATTERN SHAPING UP.
EARLY TO MID NEXT WEEK...THE MIDWEST WILL BE IN A NORTHWEST FLOW
WITH A TROUGH IN THE EAST AND RIDGING IN THE ROCKIES. WILL BE MUCH
MORE COMFORTABLE WITH LOW HUMIDITY AND TOLERABLE TEMPERATURES. MAX
TEMPS WILL BE IN THE 80S WITH MIN TEMPS IN THE 60S...WHICH IS MORE
NORMAL FOR THIS TIME OF YEAR. WITH HIGH PRESSURE OVER THE GREAT
LAKES REGION THE WEEK LOOKS DRY.
LATE NEXT WEEK AND BEYOND...RIDGING ALOFT BEGINS STRENGTHENING AGAIN
INTO THE MIDWEST. THIS WILL BRING VERY WARM TO HOT TEMPERATURES BACK
INTO THE REGION BY THE MIDDLE OF JULY BUT ALSO REMAINING DRY. THIS
SCENARIO DESCRIBED ABOVE MAY WORSEN THE DROUGHT CONDITIONS.
HAASE
AVIATION... /ISSUED 1130 PM CDT WED JUL 4 2012/
UPPER LEVEL RIDGE WILL KEEP CLEAR SKIES AND VERY WARM
TEMPERATURES OVER THE AREA THROUGH THURSDAY NIGHT. VFR CONDITIONS WITH
LIGHT SOUTHWEST WINDS WILL PREVAIL AT ALL SITES...BUT WILL
INCREASE TO AROUND 12 KTS DURING MID DAY HOURS.
ERVIN
CLIMATE...
RECORD HIGHS FOR JULY 5...
MOLINE.........105 IN 1936
CEDAR RAPIDS...110 IN 1911
DUBUQUE........104 IN 1911
BURLINGTON.....108 IN 1936
RECORD HIGHS FOR JULY 6...
MOLINE.........105 IN 1936
CEDAR RAPIDS...102 IN 1936
DUBUQUE........102 IN 1936
BURLINGTON.....105 IN 1936
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...EXCESSIVE HEAT WARNING UNTIL 7 AM CDT SATURDAY 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...EXCESSIVE HEAT WARNING UNTIL 7 AM CDT SATURDAY FOR BUREAU-
CARROLL-HANCOCK-HENDERSON-HENRY IL-JO DAVIESS-MCDONOUGH-
MERCER-PUTNAM-ROCK ISLAND-STEPHENSON-WARREN-WHITESIDE.
MO...EXCESSIVE HEAT WARNING UNTIL 7 AM CDT SATURDAY FOR CLARK-
SCOTLAND.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
750 AM MDT THU JUL 5 2012
.UPDATE...
ISSUED AT 748 AM MDT THU JUL 5 2012
ONLY CHANGE WAS TO UPGRADE THE REMAINING FIRE WEATHER WATCH TO A
RED FLAG WARNING. WILL LIKELY BE A LOW END EVENT...BUT WITH THE
EXTREMELY DRY FUELS WILL ERROR ON THE SIDE OF CAUTION.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 432 AM MDT THU JUL 5 2012
FORECAST CONCERNS THIS PERIOD WILL BE HIGH TEMPERATURES/FIRE WEATHER
CONCERNS. SATELLITE SHOWING SAME PATTERN WITH UPPER TROUGHS ALONG
EACH COAST AND BROAD RIDGE OVER MOST OF THE COUNTRY. TROUGHS HAVE
SHOWN A LITTLE TREND TOWARD DEEPENING. SUBTROPICAL MOISTURE
CONTINUES TO FEED IN AROUND THE UPPER HIGH. COLD FRONT MOVED INTO THE
NORTHERN PORTIONS AND HELPED BRING SOME PRECIPITATION TO THAT AREA .
MODELS INITIALIZED FINE AT JET LEVEL. AT MID LEVELS THE NAM...SREF...
UKMET AND CANADIAN WERE DOING THE BEST. THE NAM...SREF...CANADIAN...
AND SREF WERE DOING VERY WELL ON THE SURFACE WIND/PRESSURE FIELD.
IN GENERAL MODELS WERE DOING WELL ON LOW LEVEL THERMAL FIELD WITH
THE NAM...UKMET...AND CANADIAN DOING A LITTLE BETTER AND THE ECMWF
THE WORST.
TODAY/TONIGHT...HAVE HAD LINGERING CONVECTION BUT IS ON THE
DECREASING TREND. IT LOOKS LIKE IT WILL BE DONE BY 12Z SO LEFT ANY
MORNING MENTION OUT. OTHERWISE MAIN LIFT AND MOISTURE WILL BE
PUSHED WEST OF THE AREA WITH MUCH WARMER 700 TO 500 MB TEMPERATURES
EXPECTED. THIS WILL CAP THE AIR MASS. SO REMOVED MENTION OF
THUNDERSTORMS FROM THIS AFTERNOON AND TONIGHT. UNLESS MESOSCALE
INFLUENCES FROM OVERNIGHT THUNDERSTORMS CAUSES PROBLEMS...MAXES
SHOULD BE SIMILAR TO YESTERDAYS.
FRIDAY...COLD FRONT MOVES BACK INTO THE NORTHWEST PORTION OF THE
AREA WITH INSTABILITY AND MID LEVEL LIFT GRAZING THE WEST. THIS WAS
VERY SIMILAR TO CURRENT FORECAST AND DID NOT CHANGE. EXCEPT MAYBE
FOR THE FAR NORTHWEST...MAX TEMPERATURES SHOULD BE SIMILAR TO
THURSDAYS.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 432 AM MDT THU JUL 5 2012
FORECAST CONCERNS TURN TO HOW COOL TO MAKE TEMPERATURES THIS PERIOD
FOLLOWED BY INCREASING CHANCES FOR PRECIPITATION BEGINNING SATURDAY.
FRIDAY NIGHT...KEPT THUNDERSTORMS IN THE FAR WESTERN PORTION PER
DISCUSSION ABOVE.
SATURDAY/SATURDAY NIGHT...THIS IS WHERE THE FORECAST GETS
COMPLICATED. MODELS DIFFER ON HOW FAR THEY WANT TO MOVE A FRONT INTO
THE AREA. SO THIS RESULTS IN BIG DIFFERENCES IN THE TEMPERATURE AND
PRECIPITATION FORECASTS. IT COULD GO EITHER WAY BUT THERE WAS
SLIGHTLY MORE SUPPORT TO GO COOLER AND ADJUSTED MAXES SLIGHTLY DOWN.
MODELS ARE ALSO ALL OVER THE PLACE IN HOW HANDLE THE MID/UPPER
LEVELS. VERY WEAK LIFT IN PLACE BUT PLENTY OF MOISTURE AND
INSTABILITY...I GUESS IT IS SUMMER. MODELS HAVE A VARIETY OF QPF
SOLUTIONS. AM THINKING THE FAR WEST HAS THE BEST SHOT FOR
PRECIPITATION BUT COULD HAPPEN ABOUT ANYPLACE. SO KEPT THE CURRENT
FORECAST IN FOR THE NIGHT.
SUNDAY THROUGH WEDNESDAY...DETERMINISTIC AND ENSEMBLES HAVE COME
INTO VERY GOOD AGREEMENT ON UPCOMING PATTERN CHANGE. HIGHLY
AMPLIFIED UPPER RIDGE DEVELOPS TO THE WEST WHICH WILL BRING COOLER
AND UNSETTLED CONDITIONS TO THE AREA. FOR THE MOST PART KEPT THE
INHERITED CRH_INIT GRIDS. HOWEVER...BASED ON 850 MB TEMPERATURES
CONVERGING ON EXPECTED VALUES...DID LOWER THE HIGH TEMPERATURES ON
SUNDAY AND MONDAY. HOWEVER THOSE MAY BE TOO WARM BASED ON EASTERLY
UPSLOPE FLOW IN A POST FRONTAL REGIME. THESE DAYS AND REMAINDER OF
THE FORECAST WILL NEED TO BE LOOKED AT FOR COOLING THEM OFF.
WITH SHORTWAVE TROUGHS COMING THROUGH IN NORTH TO NORTHWEST FLOW
ALOFT IN A POST FRONTAL UPSLOPE SITUATION...LOOK TO GIVE AREA A
GOOD CHANCE OF PRECIPITATION WITH SUNDAY NIGHT THROUGH MONDAY NIGHT
LOOKING WET.
THANKS TO ALL THAT COLLABORATED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 529 AM MDT THU JUL 5 2012
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. LIGHT AND VARIABLE
WINDS WILL SHIFT TO THE SOUTH...INCREASE...AND BECOME GUSTY UNTIL
EARLY THIS EVENING.
&&
.FIRE WEATHER...
ISSUED AT 432 AM MDT THU JUL 5 2012
FOR TODAY...MESOSCALE INFLUENCES FROM CURRENT OVERNIGHT CONVECTION
MAKING THE FORECAST MORE COMPLICATED THAN EXPECTED. HOW LONG THE COLD
POOL BEHIND OUTFLOW BOUNDARIES KEEPS WINDS FROM PICKING UP PLUS
RELATIVE HUMIDITIES WILL BE KEPT HIGHER THAN ANTICIPATED. HRRR IS THE
ONLY MODEL CAPTURING CURRENT OUTFLOW BOUNDARIES. BETWEEN 15Z AND 18Z
IT SHIFTS THE WINDS BACK TO THE SOUTH AND INCREASES THEM. ALSO
TEMPERATURES LOOK TO RISE NICELY AFTER THIS.
THE FURTHER WEST COUNTIES LOOK TO HAVE THE BEST COMBINATION OF
RELATIVE HUMIDITIES...WHICH ARE CLOSE TO THRESHOLDS...AND THE
STRONGEST WINDS. ALSO SOME FIRES OCCURRED AND ARE ONGOING IN A FEW
COUNTIES IN THIS AREA. SO UPGRADED THAT AREA TO A RED FLAG WARNING.
MARGINAL CONDITIONS ARE IN THE COUNTIES JUST TO THE EAST OF THIS
AREA. KEPT THE WATCH THERE FOR NOW AND WILL LET THE DAY SHIFT LOOK AT
THE TRENDS. THE NORTHEAST MOST COUNTIES LOOK TO NOT HAVE STRONG
ENOUGH WINDS SO REMOVED THEM FROM THE WATCH.
FOR FRIDAY...POSITION OF A BOUNDARY WILL AGAIN PLAY A KEY ROLE.
RELATIVE HUMIDITIES ARE MARGINAL AT THIS TIME. AS THE FRONT MOVES IN
THE STRONGEST WINDS WILL BE PUSHED SOUTH AND EAST. TOO MUCH
UNCERTAINTY PLUS HAVE A COMPLICATED FIRE WEATHER HIGHLIGHT OUT
ALREADY SO WILL NOT ISSUE ANYTHING NOW AND MENTION IN THE HWO. THE
SOUTHEAST HALF OF THE AREA HAS THE BEST CHANCE TO REACH CRITERIA.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...RED FLAG WARNING FROM NOON MDT /1 PM CDT/ TODAY TO 7 PM MDT /8
PM CDT/ THIS EVENING FOR KSZ001-002-013>015-027>029-041-042.
CO...RED FLAG WARNING FROM NOON TODAY TO 7 PM MDT THIS EVENING FOR
COZ252>254.
NE...RED FLAG WARNING FROM NOON TODAY TO 7 PM MDT THIS EVENING FOR
NEZ079.
&&
$$
UPDATE...JTL
SHORT TERM...BULLER
LONG TERM...BULLER
AVIATION...BULLER
FIRE WEATHER...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
531 AM MDT THU JUL 5 2012
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 432 AM MDT THU JUL 5 2012
FORECAST CONCERNS THIS PERIOD WILL BE HIGH TEMPERATURES/FIRE WEATHER
CONCERNS. SATELLITE SHOWING SAME PATTERN WITH UPPER TROUGHS ALONG
EACH COAST AND BROAD RIDGE OVER MOST OF THE COUNTRY. TROUGHS HAVE
SHOWN A LITTLE TREND TOWARD DEEPENING. SUBTROPICAL MOISTURE
CONTINUES TO FEED IN AROUND THE UPPER HIGH. COLD FRONT MOVED INTO THE
NORTHERN PORTIONS AND HELPED BRING SOME PRECIPITATION TO THAT AREA .
MODELS INITIALIZED FINE AT JET LEVEL. AT MID LEVELS THE NAM...SREF...
UKMET AND CANADIAN WERE DOING THE BEST. THE NAM...SREF...CANADIAN...
AND SREF WERE DOING VERY WELL ON THE SURFACE WIND/PRESSURE FIELD.
IN GENERAL MODELS WERE DOING WELL ON LOW LEVEL THERMAL FIELD WITH
THE NAM...UKMET...AND CANADIAN DOING A LITTLE BETTER AND THE ECMWF
THE WORST.
TODAY/TONIGHT...HAVE HAD LINGERING CONVECTION BUT IS ON THE
DECREASING TREND. IT LOOKS LIKE IT WILL BE DONE BY 12Z SO LEFT ANY
MORNING MENTION OUT. OTHERWISE MAIN LIFT AND MOISTURE WILL BE
PUSHED WEST OF THE AREA WITH MUCH WARMER 700 TO 500 MB TEMPERATURES
EXPECTED. THIS WILL CAP THE AIR MASS. SO REMOVED MENTION OF
THUNDERSTORMS FROM THIS AFTERNOON AND TONIGHT. UNLESS MESOSCALE
INFLUENCES FROM OVERNIGHT THUNDERSTORMS CAUSES PROBLEMS...MAXES
SHOULD BE SIMILAR TO YESTERDAYS.
FRIDAY...COLD FRONT MOVES BACK INTO THE NORTHWEST PORTION OF THE
AREA WITH INSTABILITY AND MID LEVEL LIFT GRAZING THE WEST. THIS WAS
VERY SIMILAR TO CURRENT FORECAST AND DID NOT CHANGE. EXCEPT MAYBE
FOR THE FAR NORTHWEST...MAX TEMPERATURES SHOULD BE SIMILAR TO
THURSDAYS.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 432 AM MDT THU JUL 5 2012
FORECAST CONCERNS TURN TO HOW COOL TO MAKE TEMPERATURES THIS PERIOD
FOLLOWED BY INCREASING CHANCES FOR PRECIPITATION BEGINNING SATURDAY.
FRIDAY NIGHT...KEPT THUNDERSTORMS IN THE FAR WESTERN PORTION PER
DISCUSSION ABOVE.
SATURDAY/SATURDAY NIGHT...THIS IS WHERE THE FORECAST GETS
COMPLICATED. MODELS DIFFER ON HOW FAR THEY WANT TO MOVE A FRONT INTO
THE AREA. SO THIS RESULTS IN BIG DIFFERENCES IN THE TEMPERATURE AND
PRECIPITATION FORECASTS. IT COULD GO EITHER WAY BUT THERE WAS
SLIGHTLY MORE SUPPORT TO GO COOLER AND ADJUSTED MAXES SLIGHTLY DOWN.
MODELS ARE ALSO ALL OVER THE PLACE IN HOW HANDLE THE MID/UPPER
LEVELS. VERY WEAK LIFT IN PLACE BUT PLENTY OF MOISTURE AND
INSTABILITY...I GUESS IT IS SUMMER. MODELS HAVE A VARIETY OF QPF
SOLUTIONS. AM THINKING THE FAR WEST HAS THE BEST SHOT FOR
PRECIPITATION BUT COULD HAPPEN ABOUT ANYPLACE. SO KEPT THE CURRENT
FORECAST IN FOR THE NIGHT.
SUNDAY THROUGH WEDNESDAY...DETERMINISTIC AND ENSEMBLES HAVE COME
INTO VERY GOOD AGREEMENT ON UPCOMING PATTERN CHANGE. HIGHLY
AMPLIFIED UPPER RIDGE DEVELOPS TO THE WEST WHICH WILL BRING COOLER
AND UNSETTLED CONDITIONS TO THE AREA. FOR THE MOST PART KEPT THE
INHERITED CRH_INIT GRIDS. HOWEVER...BASED ON 850 MB TEMPERATURES
CONVERGING ON EXPECTED VALUES...DID LOWER THE HIGH TEMPERATURES ON
SUNDAY AND MONDAY. HOWEVER THOSE MAY BE TOO WARM BASED ON EASTERLY
UPSLOPE FLOW IN A POST FRONTAL REGIME. THESE DAYS AND REMAINDER OF
THE FORECAST WILL NEED TO BE LOOKED AT FOR COOLING THEM OFF.
WITH SHORTWAVE TROUGHS COMING THROUGH IN NORTH TO NORTHWEST FLOW
ALOFT IN A POST FRONTAL UPSLOPE SITUATION...LOOK TO GIVE AREA A
GOOD CHANCE OF PRECIPITATION WITH SUNDAY NIGHT THROUGH MONDAY NIGHT
LOOKING WET.
THANKS TO ALL THAT COLLABORATED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 529 AM MDT THU JUL 5 2012
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. LIGHT AND VARIABLE
WINDS WILL SHIFT TO THE SOUTH...INCREASE...AND BECOME GUSTY UNTIL
EARLY THIS EVENING.
&&
.FIRE WEATHER...
ISSUED AT 432 AM MDT THU JUL 5 2012
FOR TODAY...MESOSCALE INFLUENCES FROM CURRENT OVERNIGHT CONVECTION
MAKING THE FORECAST MORE COMPLICATED THAN EXPECTED. HOW LONG THE COLD
POOL BEHIND OUTFLOW BOUNDARIES KEEPS WINDS FROM PICKING UP PLUS
RELATIVE HUMIDITIES WILL BE KEPT HIGHER THAN ANTICIPATED. HRRR IS THE
ONLY MODEL CAPTURING CURRENT OUTFLOW BOUNDARIES. BETWEEN 15Z AND 18Z
IT SHIFTS THE WINDS BACK TO THE SOUTH AND INCREASES THEM. ALSO
TEMPERATURES LOOK TO RISE NICELY AFTER THIS.
THE FURTHER WEST COUNTIES LOOK TO HAVE THE BEST COMBINATION OF
RELATIVE HUMIDITIES...WHICH ARE CLOSE TO THRESHOLDS...AND THE
STRONGEST WINDS. ALSO SOME FIRES OCCURRED AND ARE ONGOING IN A FEW
COUNTIES IN THIS AREA. SO UPGRADED THAT AREA TO A RED FLAG WARNING.
MARGINAL CONDITIONS ARE IN THE COUNTIES JUST TO THE EAST OF THIS
AREA. KEPT THE WATCH THERE FOR NOW AND WILL LET THE DAY SHIFT LOOK AT
THE TRENDS. THE NORTHEAST MOST COUNTIES LOOK TO NOT HAVE STRONG
ENOUGH WINDS SO REMOVED THEM FROM THE WATCH.
FOR FRIDAY...POSITION OF A BOUNDARY WILL AGAIN PLAY A KEY ROLE.
RELATIVE HUMIDITIES ARE MARGINAL AT THIS TIME. AS THE FRONT MOVES IN
THE STRONGEST WINDS WILL BE PUSHED SOUTH AND EAST. TOO MUCH
UNCERTAINTY PLUS HAVE A COMPLICATED FIRE WEATHER HIGHLIGHT OUT
ALREADY SO WILL NOT ISSUE ANYTHING NOW AND MENTION IN THE HWO. THE
SOUTHEAST HALF OF THE AREA HAS THE BEST CHANCE TO REACH CRITERIA.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...RED FLAG WARNING FROM NOON MDT /1 PM CDT/ TODAY TO 7 PM MDT /8
PM CDT/ THIS EVENING FOR KSZ001-013-014-027-028-041-042.
FIRE WEATHER WATCH FROM 1 PM CDT THIS AFTERNOON THROUGH THIS
EVENING FOR KSZ002-015-029.
CO...RED FLAG WARNING FROM NOON TODAY TO 7 PM MDT THIS EVENING FOR
COZ252>254.
NE...FIRE WEATHER WATCH FROM NOON MDT TODAY THROUGH THIS EVENING FOR
NEZ079.
&&
$$
SHORT TERM...BULLER
LONG TERM...BULLER
AVIATION...BULLER
FIRE WEATHER...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
432 AM MDT THU JUL 5 2012
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 432 AM MDT THU JUL 5 2012
FORECAST CONCERNS THIS PERIOD WILL BE HIGH TEMPERATURES/FIRE WEATHER
CONCERNS. SATELLITE SHOWING SAME PATTERN WITH UPPER TROUGHS ALONG
EACH COAST AND BROAD RIDGE OVER MOST OF THE COUNTRY. TROUGHS HAVE
SHOWN A LITTLE TREND TOWARD DEEPENING. SUBTROPICAL MOISTURE
CONTINUES TO FEED IN AROUND THE UPPER HIGH. COLD FRONT MOVED INTO THE
NORTHERN PORTIONS AND HELPED BRING SOME PRECIPITATION TO THAT AREA .
MODELS INITIALIZED FINE AT JET LEVEL. AT MID LEVELS THE NAM...SREF...
UKMET AND CANADIAN WERE DOING THE BEST. THE NAM...SREF...CANADIAN...
AND SREF WERE DOING VERY WELL ON THE SURFACE WIND/PRESSURE FIELD.
IN GENERAL MODELS WERE DOING WELL ON LOW LEVEL THERMAL FIELD WITH
THE NAM...UKMET...AND CANADIAN DOING A LITTLE BETTER AND THE ECMWF
THE WORST.
TODAY/TONIGHT...HAVE HAD LINGERING CONVECTION BUT IS ON THE
DECREASING TREND. IT LOOKS LIKE IT WILL BE DONE BY 12Z SO LEFT ANY
MORNING MENTION OUT. OTHERWISE MAIN LIFT AND MOISTURE WILL BE
PUSHED WEST OF THE AREA WITH MUCH WARMER 700 TO 500 MB TEMPERATURES
EXPECTED. THIS WILL CAP THE AIR MASS. SO REMOVED MENTION OF
THUNDERSTORMS FROM THIS AFTERNOON AND TONIGHT. UNLESS MESOSCALE
INFLUENCES FROM OVERNIGHT THUNDERSTORMS CAUSES PROBLEMS...MAXES
SHOULD BE SIMILAR TO YESTERDAYS.
FRIDAY...COLD FRONT MOVES BACK INTO THE NORTHWEST PORTION OF THE
AREA WITH INSTABILITY AND MID LEVEL LIFT GRAZING THE WEST. THIS WAS
VERY SIMILAR TO CURRENT FORECAST AND DID NOT CHANGE. EXCEPT MAYBE
FOR THE FAR NORTHWEST...MAX TEMPERATURES SHOULD BE SIMILAR TO
THURSDAYS.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 432 AM MDT THU JUL 5 2012
FORECAST CONCERNS TURN TO HOW COOL TO MAKE TEMPERATURES THIS PERIOD
FOLLOWED BY INCREASING CHANCES FOR PRECIPITATION BEGINNING SATURDAY.
FRIDAY NIGHT...KEPT THUNDERSTORMS IN THE FAR WESTERN PORTION PER
DISCUSSION ABOVE.
SATURDAY/SATURDAY NIGHT...THIS IS WHERE THE FORECAST GETS
COMPLICATED. MODELS DIFFER ON HOW FAR THEY WANT TO MOVE A FRONT INTO
THE AREA. SO THIS RESULTS IN BIG DIFFERENCES IN THE TEMPERATURE AND
PRECIPITATION FORECASTS. IT COULD GO EITHER WAY BUT THERE WAS
SLIGHTLY MORE SUPPORT TO GO COOLER AND ADJUSTED MAXES SLIGHTLY DOWN.
MODELS ARE ALSO ALL OVER THE PLACE IN HOW HANDLE THE MID/UPPER
LEVELS. VERY WEAK LIFT IN PLACE BUT PLENTY OF MOISTURE AND
INSTABILITY...I GUESS IT IS SUMMER. MODELS HAVE A VARIETY OF QPF
SOLUTIONS. AM THINKING THE FAR WEST HAS THE BEST SHOT FOR
PRECIPITATION BUT COULD HAPPEN ABOUT ANYPLACE. SO KEPT THE CURRENT
FORECAST IN FOR THE NIGHT.
SUNDAY THROUGH WEDNESDAY...DETERMINISTIC AND ENSEMBLES HAVE COME
INTO VERY GOOD AGREEMENT ON UPCOMING PATTERN CHANGE. HIGHLY
AMPLIFIED UPPER RIDGE DEVELOPS TO THE WEST WHICH WILL BRING COOLER
AND UNSETTLED CONDITIONS TO THE AREA. FOR THE MOST PART KEPT THE
INHERITED CRH_INIT GRIDS. HOWEVER...BASED ON 850 MB TEMPERATURES
CONVERGING ON EXPECTED VALUES...DID LOWER THE HIGH TEMPERATURES ON
SUNDAY AND MONDAY. HOWEVER THOSE MAY BE TOO WARM BASED ON EASTERLY
UPSLOPE FLOW IN A POST FRONTAL REGIME. THESE DAYS AND REMAINDER OF
THE FORECAST WILL NEED TO BE LOOKED AT FOR COOLING THEM OFF.
WITH SHORTWAVE TROUGHS COMING THROUGH IN NORTH TO NORTHWEST FLOW
ALOFT IN A POST FRONTAL UPSLOPE SITUATION...LOOK TO GIVE AREA A
GOOD CHANCE OF PRECIPITATION WITH SUNDAY NIGHT THROUGH MONDAY NIGHT
LOOKING WET.
THANKS TO ALL THAT COLLABORATED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1155 PM MDT WED JUL 4 2012
CONVECTION CONTINUES TO ELUDE KGLD BUT OUTFLOW FROM THUNDERSTORMS
TO THE NORTH CONTINUES TO PROGRESS SOUTHWARD TOWARD THE TERMINAL.
WHILE CONFIDENCE IN THE DEVELOP OF CONVECTION IMPACTING KGLD IS
LOW...WILL CARRY TEMPO GROUP FOR A FEW HOURS TO COVER THIS
POTENTIAL. CONVECTION REMAINS WELL NORTH AND WEST OF KMCK SO NO
PLAN TO MENTION CONVECTION THERE. WINDS REMAIN
SOUTHERLY/SOUTHEASTERLY THROUGH THE DAY THURSDAY WITH GUSTS
APPROACHING 25 KTS POSSIBLE DURING THE LATE MORNING AND AFTERNOON
HOURS. GUSTS WILL SUBSIDE BY AROUND 02Z.
&&
.FIRE WEATHER...
ISSUED AT 432 AM MDT THU JUL 5 2012
FOR TODAY...MESOSCALE INFLUENCES FROM CURRENT OVERNIGHT CONVECTION
MAKING THE FORECAST MORE COMPLICATED THAN EXPECTED. HOW LONG THE COLD
POOL BEHIND OUTFLOW BOUNDARIES KEEPS WINDS FROM PICKING UP PLUS
RELATIVE HUMIDITIES WILL BE KEPT HIGHER THAN ANTICIPATED. HRRR IS THE
ONLY MODEL CAPTURING CURRENT OUTFLOW BOUNDARIES. BETWEEN 15Z AND 18Z
IT SHIFTS THE WINDS BACK TO THE SOUTH AND INCREASES THEM. ALSO
TEMPERATURES LOOK TO RISE NICELY AFTER THIS.
THE FURTHER WEST COUNTIES LOOK TO HAVE THE BEST COMBINATION OF
RELATIVE HUMIDITIES...WHICH ARE CLOSE TO THRESHOLDS...AND THE
STRONGEST WINDS. ALSO SOME FIRES OCCURRED AND ARE ONGOING IN A FEW
COUNTIES IN THIS AREA. SO UPGRADED THAT AREA TO A RED FLAG WARNING.
MARGINAL CONDITIONS ARE IN THE COUNTIES JUST TO THE EAST OF THIS
AREA. KEPT THE WATCH THERE FOR NOW AND WILL LET THE DAY SHIFT LOOK AT
THE TRENDS. THE NORTHEAST MOST COUNTIES LOOK TO NOT HAVE STRONG
ENOUGH WINDS SO REMOVED THEM FROM THE WATCH.
FOR FRIDAY...POSITION OF A BOUNDARY WILL AGAIN PLAY A KEY ROLE.
RELATIVE HUMIDITIES ARE MARGINAL AT THIS TIME. AS THE FRONT MOVES IN
THE STRONGEST WINDS WILL BE PUSHED SOUTH AND EAST. TOO MUCH
UNCERTAINTY PLUS HAVE A COMPLICATED FIRE WEATHER HIGHLIGHT OUT
ALREADY SO WILL NOT ISSUE ANYTHING NOW AND MENTION IN THE HWO. THE
SOUTHEAST HALF OF THE AREA HAS THE BEST CHANCE TO REACH CRITERIA.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...RED FLAG WARNING FROM NOON MDT /1 PM CDT/ TODAY TO 7 PM MDT /8
PM CDT/ THIS EVENING FOR KSZ001-013-014-027-028-041-042.
FIRE WEATHER WATCH FROM 1 PM CDT THIS AFTERNOON THROUGH THIS
EVENING FOR KSZ002-015-029.
CO...RED FLAG WARNING FROM NOON TODAY TO 7 PM MDT THIS EVENING FOR
COZ252>254.
NE...FIRE WEATHER WATCH FROM NOON MDT TODAY THROUGH THIS EVENING FOR
NEZ079.
&&
$$
SHORT TERM...BULLER
LONG TERM...BULLER
AVIATION...FOLTZ
FIRE WEATHER...BULLER
AREA FORECAST DISCUSSION
NWS JACKSON KY
1157 AM EDT THU JUL 5 2012
.UPDATE...
ISSUED AT 1157 AM EDT THU JUL 5 2012
OUTFLOW BOUNDARY CONTINUES TO DROP SOUTH AND IS NOW BEGINNING TO PUSH
INTO FAR NORTHERN KENTUCKY. THE BOUNDARY HAS TURNED QUITE ACTIVE TO
THE EAST CLOSE TO CHARLESTON...BUT HAS NOT YET TURNED ACTIVE FURTHER
TO THE WEST. HOWEVER...WITH 5000J/KG OF SBCAPE DEVELOPING...I EXPECT
TO SEE SOME EXPANSION TO THE WEST ALONG THIS LINE AS WE HEAD THROUGH
THE AFTERNOON. GIVEN THE THREAT...SPC HAS ISSUED A SEVERE
THUNDERSTORM WATCH THROUGH 7 PM TONIGHT FOR AREA MAINLY TO THE EAST
OF I-75. PEOPLE WITH OUTDOOR PLANS SHOULD STAY TUNED TO THE WEATHER
THIS AFTERNOON AND BE PREPARED TO TAKE ACTION. HAVE ALSO INCREASED
POPS TO LIKELY FOR THE AREA THIS AFTERNOON AS MOST AREAS SHOULD SEE
SOME PRECIPITATION.
UPDATE ISSUED AT 924 AM EDT THU JUL 5 2012
MCS DEVELOPED OVER SOUTHERN MICHIGAN EARLY THIS MORNING AND HAS
WEAKENED AS IT TRACKED SOUTH INTO NORTHERN AND CENTRAL OHIO.
HOWEVER...THIS SYSTEM HAS DEVELOPED A COLD POOL AND MCV WHICH WILL
CONTINUE TRACKING SOUTH INTO THIS AFTERNOON AND EVENING. AFTER THE
INVERSION BREAKS THIS MORNING...SBCAPE WILL SURGE TO AT LEAST 4000
J/KG AN POTENTIALLY HIGHER. WITH THE MCV DROPPING SOUTH DURING THE
PEAK HEATING...WE SHOULD SEE PRETTY DECENT SHOWER AND THUNDERSTORM
DEVELOPMENT. THIS IS CERTAINLY SUPPORTED BY THE HRRR AND RUC.
THUS...HAVE INCREASED POPS TO AROUND 40 ACROSS EASTERN KENTUCKY AND
MAY NEED TO GO EVEN HIGHER...BUT WILL WAIT TO SEE HOW THE MCV
DEVELOPS UPSTREAM BEFORE JUMPING ON BOARD COMPLETELY.
REGARDLESS...MUCH LIKE THE PAST FEW DAYS...ANY OUTFLOW BOUNDARIES
WILL EASILY BE CAPABLE OF 40 MPH WINDS AND NEAR THE STRONGER
THUNDERSTORMS WINDS COULD REACH 60 MPH. THUS...THE MAIN THREAT WILL
BE DAMAGING WINDS. A FEW MORE ORGANIZED STORMS WILL BE CAPABLE OF
HAIL...BUT I EXPECT THE MAIN THREAT TO BE DAMAGING WINDS. FORECAST
HAS BEEN UPDATED TO REFLECT ALL OF THESE CHANGES. DEPENDING ON HOW
FAST CONVECTION DEVELOPS TODAY...THAT COULD PUT OUR HIGHS A TAD LOWER
THAN CURRENTLY FORECAST. BUT FOR NOW WILL STICK CLOSE TO OUR PREVIOUS
FORECAST AND WAIT TO SEE HOW THINGS DEVELOP.
UPDATE ISSUED AT 640 AM EDT THU JUL 5 2012
MAINLY FRESHENED UP THE GRIDS TO ACCOUNT FOR THE LATEST OBSERVATIONAL
TRENDS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 352 AM EDT THU JUL 5 2012
HEAT WILL CONTINUE TO BE THE MAIN STORY AS THE CENTRAL CONUS UPPER
LEVEL RIDGE EXPANDS MORE INTO THE OHIO AND TENNESSEE VALLEYS THROUGH
THE SHORT TERM. RECORD HIGHS WILL GET SQUASHED TODAY THROUGH SATURDAY
WITH READINGS RANGING IN THE 95 TO 100 DEGREE RANGE FOR MOST
LOCATIONS. WE HAD A FEW SPOTS EVEN IN THE EAST CREEP TO OVER A 100
DEGREE HEAT INDICES YESTERDAY...AND SINCE TEMPERATURES WILL GENERALLY
BE A DEGREE OR SO WARMER TODAY AND AGAIN ON FRIDAY...HAVE GONE AHEAD
AND EXPANDED THE HEAT ADVISORY FOR THE REST OF THE AREA. HAVE ALSO
EXTENDED THE ADVISORY THROUGH SATURDAY...AS READINGS LOOK TO BE
SIMILAR TO FRIDAY...WITH HEAT INDICES GENERALLY PEAKING IN THE 100
TO 105 DEGREE RANGE...WITH SLIGHTLY HIGHER VALUES TOWARDS THE
BLUEGRASS AND WEST OF I-75.
THE CONVECTIVE TRENDS CONTINUE TO BE CHALLENGING THROUGH THE SHORT
TERM...HOWEVER GIVEN THE MORE LIMITED COVERAGE THAT OCCURRED
YESTERDAY AND THE LACK OF DEEPER MOISTURE AS WELL QUESTIONABLE
TRIGGERS THROUGH FRIDAY...ITS HARD TO REALLY ADVERTISE MORE THAN
ISOLATED POPS...SO HAVE STUCK WITH THIS IDEA FROM THE INHERITED
FORECAST. THE NAM HAS BEEN PLAYING UP A POTENTIAL MCS FOR
TONIGHT...HOWEVER GIVEN THE POOR CONVECTIVE INITIALIZATION...THERE IS
NOT MUCH CONFIDENCE IN THIS SCENARIO AT THIS TIME.
FOR TEMPERATURES...PRETTY MUCH ADDED A DEGREE OR SO FROM THE HIGHS
THAT WERE ACHIEVED ON WEDNESDAY FOR TODAY...AND THEN ANOTHER DEGREE
FOR FRIDAY. LOWS TONIGHT WILL GENERALLY BE BETWEEN 70 AND 75...WITH A
FEW SHELTERED VALLEYS DIPPING INTO THE UPPER 60S.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 352 AM EDT THU JUL 5 2012
FOR THE EXTENDED THE MODELS ARE IN FAIRLY GOOD AGREEMENT THAT THE
RENEWED UPPER RIDGE OVER THE MID SECTION OF THE NATION WILL BE
SHUNTED WESTWARD AND WEAKENED BY TROUGHING TO THE NORTHEAST STARTING
DURING THE LATTER PART OF THE WEEKEND. HEIGHTS WILL FALL THROUGH
EAST KENTUCKY BEGINNING ON SUNDAY AND CONTINUE INTO TUESDAY WHEN THE
NORTHEAST TROUGH AXIS PASSES THROUGH THE REGION ACCOMPANIED BY AT
LEAST SOME SHORTWAVE ENERGY. FOR WEDNESDAY...BOTH THE GFS AND LATEST
ECMWF HAVE PARKED A MINIMA OF HEIGHTS OVER EAST KENTUCKY IN RESPONSE
TO RIDGING BUILDING OVER THE WEST. THIS APPEARS TO BE THE CLEAR
PATTERN CHANGE THAT WE HAVE BEEN WAITING AND HOPING FOR AND WILL
BREAK THE HEAT WAVE. SEVERAL RUNS IN A ROW HAVE CONFIRMED THE
BREAKDOWN AND RETREAT OF THE RIDGE SO CONFIDENCE IS PRETTY GOOD THAT
WE CAN TALK SERIOUSLY ABOUT TEMPERATURES RETURNING TO SEASONAL
NORMALS BEFORE TOO LONG INTO THE START OF NEXT WEEK.
SENSIBLE WEATHER WILL FEATURE ANOTHER VERY WARM DAY OR TWO OVER THE
WEEKEND WITH UPPER RIDGING LIKELY KEEPING ANY CONVECTION AT BAY ON
SATURDAY WITH A BIT HIGHER PCPN POTENTIAL ANTICIPATED FOR SUNDAY AS
HEIGHTS FALL ALOFT AND A WAVY SFC BOUNDARY CREEPS CLOSER FROM THE
NORTH. IT IS THIS BOUNDARY THAT HAS BEEN IN MOST DISPUTE AMONG THE
MODELS THESE PAST SEVERAL RUNS WITH THE GFS AND GEM PUSHING ITO
SOUTH INTO...AN IN SOME CASES THROUGH...KENTUCKY AS EARLY AS SUNDAY
EVENING. THE NEW...AND PREFERRED...ECMWF WILL SAG THIS FRONT INTO
OUR PART OF THE STATE ON MONDAY PROPER AND HOLD IT THERE AS A PRIME
WEATHER FACTOR INTO TUESDAY. LATER ON FOR WEDNESDAY...IT FORMS A
WAVE ON THE BOUNDARY OVER EAST KENTUCKY THAT...SHOULD THIS OCCUR...
WILL CERTAINLY HEARTEN OUR HOPES FOR DROUGHT MITIGATING RAINS. HAVE
NOT BOUGHT TOTALLY INTO THIS SCENARIO AS OF YET...BUT DID GUIDE THE
GRIDS TOWARDS IT IN CONJUNCTION WITH THE CR POPULATION SCRIPT
STARTING POINT.
BY THE START OF THE NEW WEEK WE SHOULD BE LOOKING AT TEMPERATURES
CLOSER TO NORMAL AND A RETURN OF DECENT CHANCES OF CONVECTION AND
MUCH NEEDED RAINFALL.
THE GRID LOAD CAME IN AS A PRETTY GOOD AMALGAM OF THE ECMWF AND GFS
SO ONLY HAD TO TWEAK THE POPS A TAD EACH DAY TO TILT THE SCALE MORE
TOWARD THE OVERSEAS MODEL AND ALSO ENHANCE THE DIURNAL NATURE OF THE
POPS. IN ADDITION...MADE SOME FINE TUNE ADJUSTMENTS TO THE LOW
TEMPERATURES EACH NIGHT TO ACCOUNT FOR SOME TERRAN DETAILS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 640 AM EDT THU JUL 5 2012
EXPECT VFR CONDITIONS TO REIGN ACROSS THE AREA THE MAJORITY OF THE
TIME. ISOLATED THUNDERSTORMS WILL AGAIN BE POSSIBLE THIS
AFTERNOON...HOWEVER WITH THE LIMITED AREAL COVERAGE...WILL CONTINUE
TO LEAVE OUT THE MENTION IN THE TAFS. WINDS WILL BE LIGHT AND
VARIABLE THROUGH THE MID-MORNING...BEFORE ENGAGING OUT OF THE
NORTHWEST BETWEEN 5 AND 8 KTS DURING THE DAY...AND THEN DIMINISHING
TOWARDS DUSK.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY UNTIL 8 PM EDT SATURDAY FOR KYZ044-050>052-058>060-
068-069-079-080-083>088-104-106>120.
&&
$$
UPDATE...KAS
SHORT TERM...GEOGERIAN
LONG TERM....GREIF
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS JACKSON KY
924 AM EDT THU JUL 5 2012
.UPDATE...
ISSUED AT 924 AM EDT THU JUL 5 2012
MCS DEVELOPED OVER SOUTHERN MICHIGAN EARLY THIS MORNING AND HAS
WEAKENED AS IT TRACKED SOUTH INTO NORTHERN AND CENTRAL OHIO.
HOWEVER...THIS SYSTEM HAS DEVELOPED A COLD POOL AND MCV WHICH WILL
CONTINUE TRACKING SOUTH INTO THIS AFTERNOON AND EVENING. AFTER THE
INVERSION BREAKS THIS MORNING...SBCAPE WILL SURGE TO AT LEAST 4000
J/KG AN POTENTIALLY HIGHER. WITH THE MCV DROPPING SOUTH DURING THE
PEAK HEATING...WE SHOULD SEE PRETTY DECENT SHOWER AND THUNDERSTORM
DEVELOPMENT. THIS IS CERTAINLY SUPPORTED BY THE HRRR AND RUC.
THUS...HAVE INCREASED POPS TO AROUND 40 ACROSS EASTERN KENTUCKY AND
MAY NEED TO GO EVEN HIGHER...BUT WILL WAIT TO SEE HOW THE MCV
DEVELOPS UPSTREAM BEFORE JUMPING ON BOARD COMPLETELY.
REGARDLESS...MUCH LIKE THE PAST FEW DAYS...ANY OUTFLOW BOUNDARIES
WILL EASILY BE CAPABLE OF 40 MPH WINDS AND NEAR THE STRONGER
THUNDERSTORMS WINDS COULD REACH 60 MPH. THUS...THE MAIN THREAT WILL
BE DAMAGING WINDS. A FEW MORE ORGANIZED STORMS WILL BE CAPABLE OF
HAIL...BUT I EXPECT THE MAIN THREAT TO BE DAMAGING WINDS. FORECAST
HAS BEEN UPDATED TO REFLECT ALL OF THESE CHANGES. DEPENDING ON HOW
FAST CONVECTION DEVELOPS TODAY...THAT COULD PUT OUR HIGHS A TAD LOWER
THAN CURRENTLY FORECAST. BUT FOR NOW WILL STICK CLOSE TO OUR PREVIOUS
FORECAST AND WAIT TO SEE HOW THINGS DEVELOP.
UPDATE ISSUED AT 640 AM EDT THU JUL 5 2012
MAINLY FRESHENED UP THE GRIDS TO ACCOUNT FOR THE LATEST OBSERVATIONAL
TRENDS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 352 AM EDT THU JUL 5 2012
HEAT WILL CONTINUE TO BE THE MAIN STORY AS THE CENTRAL CONUS UPPER
LEVEL RIDGE EXPANDS MORE INTO THE OHIO AND TENNESSEE VALLEYS THROUGH
THE SHORT TERM. RECORD HIGHS WILL GET SQUASHED TODAY THROUGH SATURDAY
WITH READINGS RANGING IN THE 95 TO 100 DEGREE RANGE FOR MOST
LOCATIONS. WE HAD A FEW SPOTS EVEN IN THE EAST CREEP TO OVER A 100
DEGREE HEAT INDICES YESTERDAY...AND SINCE TEMPERATURES WILL GENERALLY
BE A DEGREE OR SO WARMER TODAY AND AGAIN ON FRIDAY...HAVE GONE AHEAD
AND EXPANDED THE HEAT ADVISORY FOR THE REST OF THE AREA. HAVE ALSO
EXTENDED THE ADVISORY THROUGH SATURDAY...AS READINGS LOOK TO BE
SIMILAR TO FRIDAY...WITH HEAT INDICES GENERALLY PEAKING IN THE 100
TO 105 DEGREE RANGE...WITH SLIGHTLY HIGHER VALUES TOWARDS THE
BLUEGRASS AND WEST OF I-75.
THE CONVECTIVE TRENDS CONTINUE TO BE CHALLENGING THROUGH THE SHORT
TERM...HOWEVER GIVEN THE MORE LIMITED COVERAGE THAT OCCURRED
YESTERDAY AND THE LACK OF DEEPER MOISTURE AS WELL QUESTIONABLE
TRIGGERS THROUGH FRIDAY...ITS HARD TO REALLY ADVERTISE MORE THAN
ISOLATED POPS...SO HAVE STUCK WITH THIS IDEA FROM THE INHERITED
FORECAST. THE NAM HAS BEEN PLAYING UP A POTENTIAL MCS FOR
TONIGHT...HOWEVER GIVEN THE POOR CONVECTIVE INITIALIZATION...THERE IS
NOT MUCH CONFIDENCE IN THIS SCENARIO AT THIS TIME.
FOR TEMPERATURES...PRETTY MUCH ADDED A DEGREE OR SO FROM THE HIGHS
THAT WERE ACHIEVED ON WEDNESDAY FOR TODAY...AND THEN ANOTHER DEGREE
FOR FRIDAY. LOWS TONIGHT WILL GENERALLY BE BETWEEN 70 AND 75...WITH A
FEW SHELTERED VALLEYS DIPPING INTO THE UPPER 60S.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 352 AM EDT THU JUL 5 2012
FOR THE EXTENDED THE MODELS ARE IN FAIRLY GOOD AGREEMENT THAT THE
RENEWED UPPER RIDGE OVER THE MID SECTION OF THE NATION WILL BE
SHUNTED WESTWARD AND WEAKENED BY TROUGHING TO THE NORTHEAST STARTING
DURING THE LATTER PART OF THE WEEKEND. HEIGHTS WILL FALL THROUGH
EAST KENTUCKY BEGINNING ON SUNDAY AND CONTINUE INTO TUESDAY WHEN THE
NORTHEAST TROUGH AXIS PASSES THROUGH THE REGION ACCOMPANIED BY AT
LEAST SOME SHORTWAVE ENERGY. FOR WEDNESDAY...BOTH THE GFS AND LATEST
ECMWF HAVE PARKED A MINIMA OF HEIGHTS OVER EAST KENTUCKY IN RESPONSE
TO RIDGING BUILDING OVER THE WEST. THIS APPEARS TO BE THE CLEAR
PATTERN CHANGE THAT WE HAVE BEEN WAITING AND HOPING FOR AND WILL
BREAK THE HEAT WAVE. SEVERAL RUNS IN A ROW HAVE CONFIRMED THE
BREAKDOWN AND RETREAT OF THE RIDGE SO CONFIDENCE IS PRETTY GOOD THAT
WE CAN TALK SERIOUSLY ABOUT TEMPERATURES RETURNING TO SEASONAL
NORMALS BEFORE TOO LONG INTO THE START OF NEXT WEEK.
SENSIBLE WEATHER WILL FEATURE ANOTHER VERY WARM DAY OR TWO OVER THE
WEEKEND WITH UPPER RIDGING LIKELY KEEPING ANY CONVECTION AT BAY ON
SATURDAY WITH A BIT HIGHER PCPN POTENTIAL ANTICIPATED FOR SUNDAY AS
HEIGHTS FALL ALOFT AND A WAVY SFC BOUNDARY CREEPS CLOSER FROM THE
NORTH. IT IS THIS BOUNDARY THAT HAS BEEN IN MOST DISPUTE AMONG THE
MODELS THESE PAST SEVERAL RUNS WITH THE GFS AND GEM PUSHING ITO
SOUTH INTO...AN IN SOME CASES THROUGH...KENTUCKY AS EARLY AS SUNDAY
EVENING. THE NEW...AND PREFERRED...ECMWF WILL SAG THIS FRONT INTO
OUR PART OF THE STATE ON MONDAY PROPER AND HOLD IT THERE AS A PRIME
WEATHER FACTOR INTO TUESDAY. LATER ON FOR WEDNESDAY...IT FORMS A
WAVE ON THE BOUNDARY OVER EAST KENTUCKY THAT...SHOULD THIS OCCUR...
WILL CERTAINLY HEARTEN OUR HOPES FOR DROUGHT MITIGATING RAINS. HAVE
NOT BOUGHT TOTALLY INTO THIS SCENARIO AS OF YET...BUT DID GUIDE THE
GRIDS TOWARDS IT IN CONJUNCTION WITH THE CR POPULATION SCRIPT
STARTING POINT.
BY THE START OF THE NEW WEEK WE SHOULD BE LOOKING AT TEMPERATURES
CLOSER TO NORMAL AND A RETURN OF DECENT CHANCES OF CONVECTION AND
MUCH NEEDED RAINFALL.
THE GRID LOAD CAME IN AS A PRETTY GOOD AMALGAM OF THE ECMWF AND GFS
SO ONLY HAD TO TWEAK THE POPS A TAD EACH DAY TO TILT THE SCALE MORE
TOWARD THE OVERSEAS MODEL AND ALSO ENHANCE THE DIURNAL NATURE OF THE
POPS. IN ADDITION...MADE SOME FINE TUNE ADJUSTMENTS TO THE LOW
TEMPERATURES EACH NIGHT TO ACCOUNT FOR SOME TERRAN DETAILS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 640 AM EDT THU JUL 5 2012
EXPECT VFR CONDITIONS TO REIGN ACROSS THE AREA THE MAJORITY OF THE
TIME. ISOLATED THUNDERSTORMS WILL AGAIN BE POSSIBLE THIS
AFTERNOON...HOWEVER WITH THE LIMITED AREAL COVERAGE...WILL CONTINUE
TO LEAVE OUT THE MENTION IN THE TAFS. WINDS WILL BE LIGHT AND
VARIABLE THROUGH THE MID-MORNING...BEFORE ENGAGING OUT OF THE
NORTHWEST BETWEEN 5 AND 8 KTS DURING THE DAY...AND THEN DIMINISHING
TOWARDS DUSK.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY UNTIL 8 PM EDT SATURDAY FOR KYZ044-050>052-058>060-
068-069-079-080-083>088-104-106>120.
&&
$$
UPDATE...KAS
SHORT TERM...GEOGERIAN
LONG TERM....GREIF
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1005 AM EDT THU JUL 5 2012
.SYNOPSIS...
AN UPPER LOW WILL CONTINUE TO MOVE EAST THROUGH THE MARITIMES TODAY.
HIGH PRESSURE WILL BRIEFLY BUILD ACROSS THE REGION LATER TODAY
INTO FRIDAY. ANOTHER COLD FRONT WILL APPROACH FROM THE WEST FRIDAY
NIGHT AND CROSS THE REGION SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
1000 AM UPDATE...NO MAJOR CHANGES MADE FOR THIS UPDATE. ADJUSTED
POPS TO MATCH CURRENT RADAR TRENDS; THE LAST LINGERING PRECIP HAS
MOVED OFF SHORE, BUT EXPECT SHOWERS TO POP UP AGAIN THIS
AFTERNOON. SATELLITE IMAGERY IS SHOWING SOME BREAKS IN THE CLOUDS
ACROSS CENTRAL/DOWNEAST AREAS, WHICH INCREASES THE POTENTIAL FOR
ISOLATED THUNDERSTORMS THIS AFTERNOON. HOWEVER, INSTABILITY LOOKS
TO BE TOO MINIMAL FOR THUNDER OVER THE FAR NORTH. THE REST OF THE
FORECAST IS ON TRACK.
PREVIOUS DISCUSSION...
CHALLENGE IS HOW MUCH RAINFALL AND TEMPERATURES.
THE LATEST RADAR TRENDS SHOW SHOWERS AND ISOLD TSTMS OVER THE
EASTERN 1/2 OF THE CWA. THE BULK OF THE ACTIVITY IS E OF HOULTON
AND ACROSS THE INTERIOR DOWNEAST AND COASTAL REGIONS. THE LATEST
HRRR AND RUC LINED UP WELL THROUGH 12Z ALTHOUGH A BIT OVERDONE AS
FAR AS AREAL COVERAGE. MANUAL ADJUSTMENTS WERE MADE TO THE POPS TO
FIT BETTER W/THE RADAR AND SATL IMAGERY. THIS MEANS HIGHER PRECIP
CHANCES(60%) IN THE AFOREMENTIONED AREAS THIS MORNING. THE CLOSED
LOW IS SHOWN TO MIGRATE ACROSS THE GULF OF MAINE INTO THE
MARITIMES THIS EVENING. AS IT DOES SO, THE INVERTED TROF FROM THE
SFC LOW WILL SLIDE E. AFTER 12Z, DECIDED ON THE GFS AND ECMWF TO
POPS AS THEY APPEAR TO HAVE A GOOD HANDLE ON THE SYNOPTIC
SITUATION AND AREAL PLACEMENT OF QPF . THEREFORE, THE DECISION WAS
TO GO W/40-50% POPS LATER THIS MORNING INTO THE AFTERNOON FOR
SHOWERS. SOUNDINGS FROM THE GFS NOT OVERLY UNSTABLE W/SBCAPE OF
400-500 JOULES. THIS WILL ALSO BE DEPENDENT ON TEMPERATURES THIS
AFTERNOON. SATL IR IMAGERY DOES SHOW SOME PARTIAL CLEARING THIS
MORNING WHICH WILL AID IN HEATING. LAPSE RATE ARE MEAGER AT BEST
(5.5-6C/KM). SOME COOLING ALOFT IS NOTED. DECIDED TO CARRY ISOLD
TSTMS TO ACCOUNT FOR THIS AWAY FROM THE COAST AND MAINLY ALONG THE
EASTERN 1/2 OF THE CWA ALONG THE CONVERGENCE ZONE. LIGHT FLOW
ALOFT AND HIGH PWS(1.5") AND FZL LVLS OF 12.5 FT WILL LEAD TO
HEAVY RAINFALL IN ANY TSTMS. A BLEND OF THE GFS/ECMWF AND HPC WAS
USED FOR THE QPF W/MANUAL ADJUSTMENTS.
ACTIVITY WINDS DOWN TONIGHT AS THE LOW PULLS E AND LLVL
CONVERGENCE WEAKENS. PARTIAL CLEARING IS EXPECTED LATER TONIGHT
AND THIS COUPLED W/A WET SFC WILL ALLOW FOR SOME FOG FORMATION.
DECIDED TO ADD FOG FOR ALL AREAS. HYDROLAPSE RATES FROM THE MDL
SOUNDINGS SUPPORT FOG POTENTIAL. DAYCREW WILL NEED TO ASSESS THIS
FURTHER TODAY. RAISED DAYCREW/S MINS UP A CATEGORY USING THE LAMP
AND NAM12 TEMPERATURES.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
WINDS WILL TURN SOUTHWEST ON FRIDAY ALLOWING FOR WARMER TEMPERATURES
ACROSS THE FA. A SHORT WAVE MOVING ACROSS FROM THE WEST WILL BRING
THE CHANCE OF LATE DAY SHOWERS AND TSTMS TO MAINLY NORTHERN PORTIONS
OF THE FA. SB CAPES LOOK RATHER MODEST AS DO 0-6 KM SHEAR VALUES SO
SEVERE POTENTIAL NOT LOOKING ALL THAT HIGH. SHOWERS AND TSTMS WILL
LIKELY PERSIST INTO FRIDAY EVENING AS THE SHORT WAVE AND ASSOCIATED
COLD FRONT CROSSES THE REGION. A SECONDARY COLD FRONT COLD FRONT
WILL CROSS THE REGION SATURDAY WITH ANOTHER CHANCE FOR SHOWERS AND
TSTMS. HIGHS ON SATURDAY WILL RANGE FROM THE LOW TO MID 80S NORTH
AND MID TO UPPER 80S DOWNEAST.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AN UPPER LOW WILL REMAIN ACROSS EASTERN CANADA SATURDAY NIGHT INTO
EARLY NEXT WEEK AS SURFACE HIGH PRESSURE BUILD EAST. WEATHER
CONDITIONS DURING THE LONG TERM SHOULD BE MAINLY DRY BUT WITH WEAK
DISTURBANCES MOVING THROUGH COULDN`T RULE OUT AN ISOLATED SHOWER OR
TSTM FROM TIME TO TIME. TEMPERATURES THROUGH THE PERIOD WILL BE NEAR
NORMAL FOR THIS TIME OF YEAR.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
NEAR TERM: IFR/MVFR CONDITIONS THROUGH MID MORNING AND THEN
CONDITIONS LOOK LIKE THEY WILL IMPROVE TO VFR LATER THIS AFTERNOON
OR EVENING. A RETURN TO MVFR AND POSSIBLY IFR LATER TONIGHT W/FOG
DEVELOPING.
SHORT TERM: SCT TSTMS ARE EXPECTED MAINLY NRN AREAS FRIDAY AND THE
REGION WIDE ON SATURDAY. CONDITIONS SHOULD BE MAINLY VFR THROUGH
THE PERIOD BUT COULD DECREASE TO MVFR IN ANY HEAVIER TSTMS FRIDAY
AND SATURDAY.
&&
.MARINE...
NEAR TERM: NO HEADLINES THIS TERM. WINDS WILL BE GENERALLY LIGHT
FROM THE NNE AT 10 KTS OR LESS. SWELLS WILL BE COMMON THIS TERM
W/PERIODS OF 8-9 SECONDS. STAYED W/DAYCREW ASSESSMENT OF 2-3 FOOT
WAVES.
SHORT TERM: WINDS/SEAS SHOULD BE BELOW SCA LEVELS THROUGH THE PERIOD.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...HASTINGS/HEWITT
SHORT TERM...DUDA
LONG TERM...DUDA
AVIATION...HASTINGS/HEWITT
MARINE...HASTINGS/HEWITT/DUDA
AREA FORECAST DISCUSSION
NWS CARIBOU ME
723 AM EDT THU JUL 5 2012
.SYNOPSIS...
AN UPPER LOW WILL CONTINUE TO MOVE EAST THROUGH THE MARITIMES TODAY.
HIGH PRESSURE WILL BRIEFLY BUILD ACROSS THE REGION LATER TODAY
INTO FRIDAY. ANOTHER COLD FRONT WILL APPROACH FROM THE WEST FRIDAY
NIGHT AND CROSS THE REGION SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE: ADJUSTED THE POPS TO FIT W/THE LATEST RADAR TRENDS AND
HRRR WHICH SHOW THE HIGHEST POPS ACROSS THE COAST AND EASTERN
AREAS EARLY THIS MORNING. KEPT FOG IN THROUGH 8AM AND MODIFIED
TEMPERATURES TO THE CURRENT READINGS.
PREVIOUS DISCUSSION:
CHALLENGE IS HOW MUCH RAINFALL AND TEMPERATURES.
THE LATEST RADAR TRENDS SHOW SHOWERS AND ISOLD TSTMS OVER THE
EASTERN 1/2 OF THE CWA. THE BULK OF THE ACTIVITY IS E OF HOULTON
AND ACROSS THE INTERIOR DOWNEAST AND COASTAL REGIONS. THE LATEST
HRRR AND RUC LINED UP WELL THROUGH 12Z ALTHOUGH A BIT OVERDONE AS
FAR AS AREAL COVERAGE. MANUAL ADJUSTMENTS WERE MADE TO THE POPS TO
FIT BETTER W/THE RADAR AND SATL IMAGERY. THIS MEANS HIGHER PRECIP
CHANCES(60%) IN THE AFOREMENTIONED AREAS THIS MORNING. THE CLOSED
LOW IS SHOWN TO MIGRATE ACROSS THE GULF OF MAINE INTO THE
MARITIMES THIS EVENING. AS IT DOES SO, THE INVERTED TROF FROM THE
SFC LOW WILL SLIDE E. AFTER 12Z, DECIDED ON THE GFS AND ECMWF TO
POPS AS THEY APPEAR TO HAVE A GOOD HANDLE ON THE SYNOPTIC
SITUATION AND AREAL PLACEMENT OF QPF . THEREFORE, THE DECISION WAS
TO GO W/40-50% POPS LATER THIS MORNING INTO THE AFTERNOON FOR
SHOWERS. SOUNDINGS FROM THE GFS NOT OVERLY UNSTABLE W/SBCAPE OF
400-500 JOULES. THIS WILL ALSO BE DEPENDENT ON TEMPERATURES THIS
AFTERNOON. SATL IR IMAGERY DOES SHOW SOME PARTIAL CLEARING THIS
MORNING WHICH WILL AID IN HEATING. LAPSE RATE ARE MEAGER AT BEST
(5.5-6C/KM). SOME COOLING ALOFT IS NOTED. DECIDED TO CARRY ISOLD
TSTMS TO ACCOUNT FOR THIS AWAY FROM THE COAST AND MAINLY ALONG THE
EASTERN 1/2 OF THE CWA ALONG THE CONVERGENCE ZONE. LIGHT FLOW
ALOFT AND HIGH PWS(1.5") AND FZL LVLS OF 12.5 FT WILL LEAD TO
HEAVY RAINFALL IN ANY TSTMS. A BLEND OF THE GFS/ECMWF AND HPC WAS
USED FOR THE QPF W/MANUAL ADJUSTMENTS.
ACTIVITY WINDS DOWN TONIGHT AS THE LOW PULLS E AND LLVL
CONVERGENCE WEAKENS. PARTIAL CLEARING IS EXPECTED LATER TONIGHT
AND THIS COUPLED W/A WET SFC WILL ALLOW FOR SOME FOG FORMATION.
DECIDED TO ADD FOG FOR ALL AREAS. HYDROLAPSE RATES FROM THE MDL
SOUNDINGS SUPPORT FOG POTENTIAL. DAYCREW WILL NEED TO ASSESS THIS
FURTHER TODAY. RAISED DAYCREW/S MINS UP A CATEGORY USING THE LAMP
AND NAM12 TEMPERATURES.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
WINDS WILL TURN SOUTHWEST ON FRIDAY ALLOWING FOR WARMER TEMPERATURES
ACROSS THE FA. A SHORT WAVE MOVING ACROSS FROM THE WEST WILL BRING
THE CHANCE OF LATE DAY SHOWERS AND TSTMS TO MAINLY NORTHERN PORTIONS
OF THE FA. SB CAPES LOOK RATHER MODEST AS DO 0-6 KM SHEAR VALUES SO
SEVERE POTENTIAL NOT LOOKING ALL THAT HIGH. SHOWERS AND TSTMS WILL
LIKELY PERSIST INTO FRIDAY EVENING AS THE SHORT WAVE AND ASSOCIATED
COLD FRONT CROSSES THE REGION. A SECONDARY COLD FRONT COLD FRONT
WILL CROSS THE REGION SATURDAY WITH ANOTHER CHANCE FOR SHOWERS AND
TSTMS. HIGHS ON SATURDAY WILL RANGE FROM THE LOW TO MID 80S NORTH
AND MID TO UPPER 80S DOWNEAST.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AN UPPER LOW WILL REMAIN ACROSS EASTERN CANADA SATURDAY NIGHT INTO
EARLY NEXT WEEK AS SURFACE HIGH PRESSURE BUILD EAST. WEATHER
CONDITIONS DURING THE LONG TERM SHOULD BE MAINLY DRY BUT WITH WEAK
DISTURBANCES MOVING THROUGH COULDN`T RULE OUT AN ISOLATED SHOWER OR
TSTM FROM TIME TO TIME. TEMPERATURES THROUGH THE PERIOD WILL BE NEAR
NORMAL FOR THIS TIME OF YEAR.
&&
.AVIATION /11Z THURSDAY THROUGH MONDAY/...
NEAR TERM: IFR/MVFR CONDITIONS THROUGH MID MORNING AND THEN
CONDITIONS LOOK LIKE THEY WILL IMPROVE TO VFR LATER THIS AFTERNOON
OR EVENING. A RETURN TO MVFR AND POSSIBLY IFR LATER TONIGHT W/FOG
DEVELOPING.
SHORT TERM: SCT TSTMS ARE EXPECTED MAINLY NRN AREAS FRIDAY AND THE
REGION WIDE ON SATURDAY. CONDITIONS SHOULD BE MAINLY VFR THROUGH
THE PERIOD BUT COULD DECREASE TO MVFR IN ANY HEAVIER TSTMS FRIDAY
AND SATURDAY.
&&
.MARINE...
NEAR TERM: NO HEADLINES THIS TERM. WINDS WILL BE GENERALLY LIGHT
FROM THE NNE AT 10 KTS OR LESS. SWELLS WILL BE COMMON THIS TERM
W/PERIODS OF 8-9 SECONDS. STAYED W/DAYCREW ASSESSMENT OF 2-3 FOOT
WAVES.
SHORT TERM: WINDS/SEAS SHOULD BE BELOW SCA LEVELS THROUGH THE PERIOD.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...HEWITT
SHORT TERM...DUDA
LONG TERM...DUDA
AVIATION...HEWITT
MARINE...HEWITT/DUDA
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
732 AM EDT THU JUL 5 2012
.SYNOPSIS...
NORTHWEST WINDS ALOFT WILL CONTINUE TO BRING POTENTIALLY SEVERE
THUNDERSTORMS SOUTHEASTWARD FROM MICHIGAN AND LAKE ERIE TODAY.
BROAD HIGH PRESSURE WILL MAINTAIN HOT HUMID CONDITIONS INTO THE
WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HAVE MAINTAINED SEVERE THUNDERSTORM WATCH FOR SEVERAL NORTHERN
COUNTIES, PLUS ADDED MENTION OF STRONG WIND AND HAIL WITH
THUNDERSTORMS FURTHER SOUTH, AS ONE OR TWO MORE THUNDERSTORM
COMPLEXES MOVE SOUTHEASTWARD THROUGH THE UPPER OHIO VALLEY TODAY,
ONE THIS MORNING AND THE SECOND THIS AFTERNOON, PER RECENT RADAR
DATA AND HRRR MODEL OUTPUT.
HAVE ALSO MAINTAINED HEAT ADVISORY FOR MOST LOWER ELEVATION
COUNTIES, AS HEAT INDICES WILL PEAK NEAR 100 THIS AFTERNOON. OF
COURSE, THUNDERSTORM PASSAGES MAY CUT INTO THAT, BUT THAT IS THE
POTENTIAL.
FORECASTED TEMPERATURES AND DEW POINTS TODAY BASED ON BLEND OF
RECENT HRRR, GFS LAMP, NAM AND GFS MOS VALUES.
EXPECT SKIES TO BE PARTLY TO MOSTLY SUNNY TODAY, DEPENDING ON
MOVEMENT OF MCS, WITH A BIT LESS HUMIDITY, BUT HOT TEMPERATURES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
MID-WESTERN RIDGE WILL MOVE EASTWARD AND BUILD INTO THE UPPER
OHIO VALLEY FRIDAY, MEANING THE HOTTEST AIR WILL SHIFT EASTWARD.
WITH LOTS OF SUNSHINE FRIDAY, AND HIGHER TDS SLOWLY MAKING A
RETURN, EXPECT ANOTHER HOT AND HUMID DAY FRIDAY.
RIDGE BEGINS TO BREAK DOWN FRIDAY NIGHT AND SATURDAY AS A SERIES
OF UL WAVE MOVE ACROSS THE GREAT LAKES. MODELS ARE SHOWING A SFC
FRONT MOVING INTO THE NORTH SATURDAY MORNING AND DRIFTING
SOUTHWARD THROUGHOUT THE DAY. WILL NEED TO BRING POPS BACK IN ON
SATURDAY WITH THE UL WAVES AND SFC FRONT. STILL ANOTHER HOT AND
HUMID DAY SAT.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
THERE IS GFS/ECMWF ENSEMBLE AGREEMENT TO BEGIN THE PERIOD THAT DEEP
RIDGING WILL BE CENTERED ACROSS THE MISSOURI VALLEY. THE UPPER OHIO
VALLEY WILL BE IN A NORTHWESTERLY FLOW ON THE EASTERN PERIPHERY OF THE
RIDGE. THE MODEL CONSENSUS INDICATES AN AMPLIFYING TREND WITH THE
RIDGE DOMINATING THE WESTERN TWO THIRDS OF THE CONUS AND LOWERING
MID-LEVEL HEIGHTS ACROSS THE UPPER OHIO VALLEY AS A TROUGH BUILDS
INTO THE NORTHEAST.
AFTER A COLD FRONT DROPS SOUTHEAST ACROSS THE AREA AND BRINGS
CHANCE POPS ON SUNDAY, A DRIER AND COOLER FORECAST IS IN PLACE FOR
EARLY NEXT WEEK. HAVE GONE DRY OR WITH SILENT SLIGHT CHC POPS FOR
LOWERING HEIGHTS THROUGH WEDNESDAY. UNCERTAINTY ENTERS THE FORECAST
BY NEXT THURSDAY WITH THE POTENTIAL OF A MID-LEVEL TROUGH PUSHING
FROM THE UPPER MIDWEST SOUTHEASTWARD ACROSS THE AREA. TEMPS ARE
AROUND 5 DEGREES ABOVE NORMAL AHEAD OF THE FRONT ON SUNDAY.
TEMPERATURES WILL THEN LOWER TO NEAR SEASONABLE VALUES FOR MONDAY,
TUESDAY AND WEDNESDAY.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
CURRENTLY WATCHING MCS OVER LOWER MI. HAVE LOW CONFIDENCE ON HOW
WELL THIS WILL HOLD TOGETHER, OR WHERE IT WILL END UP GOING.
HOWEVER, WITH ITS GENERAL DIRECTION, AND TAKING INTO ACCOUNT WHERE
ACTIVITY DEVELOPED LAST NIGHT, WILL NEED TO INCLUDE A TEMPO GROUP
OF MVFR RESTRICTIONS WITH STORMS AT FKL AND DUJ THIS MORNING. IF
COMPLEX HOLDS TOGETHER, WILL NEED RESTRICTIONS IN PORTS FURTHER
SOUTH. ONCE THIS COMPLEX MOVES THROUGH A GENERAL VFR FORECAST FOR
THE REST OF THE DAY.
SFC WINDS WILL SHIFT LATER THIS MORNING FROM A SOUTHWESTERLY
DIRECTION TO A NORTHERLY DIRECTION AND INCREASE IN SPEED TO AROUND
10 TO 15KTS.
OUTLOOK...THURSDAY NIGHT THROUGH MONDAY...
VFR EXPECTED, EXCEPT FOR MORNING MVFR HAZE. RESTRICTIONS WILL ALSO
BE POSSIBLE IN SCATTERED THUNDERSTORMS LATE SATURDAY AND AGAIN ON SUNDAY
AS A FRONT MOVES SOUTHWARD THROUGH THE REGION. VFR CONDITIONS
WILL RETURN ON MONDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...HEAT ADVISORY FROM NOON TODAY TO 7 PM EDT THIS EVENING FOR
OHZ039>041-048>050-057>059-068-069.
PA...HEAT ADVISORY FROM NOON TODAY TO 7 PM EDT THIS EVENING FOR
PAZ013-014-020>023-029-031-073-075.
WV...HEAT ADVISORY FROM NOON TODAY TO 7 PM EDT THIS EVENING FOR
WVZ001>004-012-021>023.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS GLASGOW MT
933 AM MDT THU JUL 5 2012
.SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH SATURDAY...
SENT AN UPDATE THIS MORNING TO ADJUST CLOUD COVER AND POPS TO MORE
ACCURATELY REFLECT THE GROWING TREND OF MOISTURE AND PRECIPITATION
OVER THE SOUTHEASTERN CWA TODAY. HRRR MODEL SEEMS TO HAVE A GOOD
HANDLE ON THE SCATTERED/ISOLATED SHOWERS AND THUNDERSTORMS.
GENERAL EFFECTS SHOULD BE MINIMAL AS THE GREATER THREAT FOR SEVERE
STORMS IS OUTLINED OFF TO OUR SOUTHEAST. BMICKELSON
PREVIOUS SHORT TERM DISCUSSION...WATER VAPOR IMAGERY AND 500 MB
HEIGHT FIELD SHOWS SW TO ZONAL FLOW ACROSS THE NORTHERN ROCKIES
DUE TO A LARGE UPPER RIDGE OVER THE CENTRAL US. A VERY LARGE UPPER
LOW IS CURRENTLY OVER THE GULF OF ALASKA WITH A SHORTWAVE MOVING
FROM THIS LOW AND OVER THE PACIFIC NORTHWEST. THE UPPER RIDGE WILL
RETROGRADE OVER THE WESTERN US FROM THE CENTRAL US BLOCKING THE
UPPER LEVEL LOWS MOVEMENT SOUTHEAST FROM THE GULF OF ALASKA INTO
THE MIDDLE OF NEXT WEEK.
MONSOONAL FLOW IS MOVING NORTHWARD ON THE WESTERN SIDE OF THIS
UPPER LEVEL RIDGE AND HEADED FOR EASTERN MONTANA. ALSO A SHORTWAVE
CURRENTLY OVER ARIZONA IS HEADED NORTH TOWARDS MONTANA ALONG WITH
THIS MONSOONAL MOISTURE. THIS COULD BECOME A PLAYER WITH SHOWER
AND THUNDERSTORMS DEVELOPMENT THIS AFTERNOON. MODELS TAKE THIS
WAVE ACROSS SOUTHEASTERN MONTANA. SO I HAVE INCREASED POPS FOR
THIS MORNING THROUGH THURSDAY NIGHT. THE FEELING IS RIGHT NOW OUR
WESTERN ZONES WILL REMAIN DRY. AS A MATTER OF FACT WITH THE 00Z
SOUNDING BEING SO DRY WE WILL NEED TO INCREASE MID LEVEL AND LOW
LEVEL MOISTURE FOR ANY OF THE PRECIP TO REACH THE SURFACE. STILL
MODEL SOUNDING INDICATE THIS WILL HAPPEN BY 18Z. QPF TOTALS WILL
BE BETWEEN A TENTH AND A QUARTER OF AN INCH. WE ARE ALREADY SEEING
A FEW ISOLATED DRY THUNDERSTORMS ACROSS THE YELLOWSTONE VALLEY.
FRIDAY THROUGH SATURDAY...FORCING FOR ASCENT CALMS ACROSS THE
REGION AS THE LARGE RIDGE HIGH PRESSURE BUILDS INTO THE NORTHERN
ROCKIES. THIS WILL HERALD THE RETURN TO ABOVE NORMAL TEMPERATURES
AND LOWER RELATIVE HUMIDITIES BY SATURDAY AFTERNOON ACROSS CENTRAL
MONTANA. RSMITH
.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY...
MODELS ARE IN GOOD AGREEMENT FOR THE EXTENDED FORECAST. A LARGE
UPPER LEVEL RIDGE WILL COVER THE WESTERN U.S THROUGH THE PERIOD.
LOOK FOR HOT AND MAINLY DRY WEATHER. FROM SUNDAY THROUGH
TUESDAY...IT LOOKS LIKE THE RIDGE WILL BE STRONG ENOUGH TO STEER
ANY SHORTWAVES THAT TRAVEL OVER THE RIDGE ACROSS ALBERTA AND
SASKATCHEWAN. THE RIDGE DROP A BIT SOUTH TUESDAY NIGHT AND THAT
WILL START BRINGING SHORTWAVES THROUGH MONTANA. WILL MENTION A
SLIGHT CHANCE OF THUNDERSTORMS FOR THESE WAVES ON WEDNESDAY AND
THURSDAY. FORRESTER
&&
.AVIATION...
VFR. SOME HIGH AND MID LEVEL CLOUDS WILL CONTINUE TO LINGER TODAY
AS A MOISTURE FEED FROM THE SOUTHWESTERN DESERTS CONTINUES TO FEED
INTO THE AREA. THE SHOWERS AND THUNDERSTORMS IN THE KGDV AREA THIS
MORNING WILL PICK UP A BIT THIS EVENING AS A BATCH OF HEAVY RAIN
MOVES THROUGH SE MONTANA AND INTO NORTH DAKOTA. CONDITIONS MAY
BRIEFLY BECOME MVFR LATER TONIGHT ESPECIALLY AT KGDV.
OTHERWISE...SOUTHEAST WINDS WILL BE STRONGEST AT KGDV AND KGGW
THROUGH FRIDAY MORNING WITH SPEEDS REACHING 15 KTS THIS AFTERNOON.
JAMBA
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS HASTINGS NE
643 AM CDT THU JUL 5 2012
.UPDATE...A SMALL AREA OF SHOWERS...MAYBE A FEW VERY WEAK
THUNDERSTORMS CONTINUES TO LIFT NORTH EARLY THIS MORNING...MAINLY
ALONG THE HIGHWAY 281 CORRIDOR NEAR GRAND ISLAND. WE EVEN MEASURED
A FEW RATHER UNEXPECTED HUNDREDTHS OF AN INCH HERE AT THE WFO.
HAVE LINGERED A 20 PERCENT STORM CHANCE FOR ALL AREAS ALONG/NORTH
OF INTERSTATE 80 THROUGH THE REST OF THE MORNING...BUT IN ALL
LIKELIHOOD THIS ACTIVITY WILL EITHER DISSIPATE OR MOVE OUT OF THE
AREA WELL BEFORE NOON. MESO-ANALYSIS INDICATES THIS CONVECTION IS
RATHER WELL TIED TO THE EXIT CONVERGENT REGION OF A 30KT
SOUTHWESTERLY LOW LEVEL JET...WHICH SHOULD GRADUALLY WEAKEN AND
FOCUS FARTHER NORTH AS THE DAY WEARS ON. AS STATED IN EARLIER
DISCUSSION...WILL DEFER TO DAY SHIFT TO CLEAN UP LINGERING POPS
FROM THIS MORNING...AND POTENTIALLY REMOVE THE SLIGHT POP FROM THE
FAR NORTHERN CWA FOR THE AFTERNOON HOURS. INTERESTINGLY...THE
LATEST HRRR REFLECTIVITY PROG HINTS AT A FEW STORMS FLARING UP
LATE THIS AFTERNOON IN THE WESTERN CWA...WHICH IS ALSO SUPPORTED
BY THE 00Z 4KM WRF-NMM...BUT AT THIS POINT AM NOT FULLY BUYING
INTO IT AS THE PRIMARY LOW LEVEL CONVERGENCE ZONE SHOULD BE
FOCUSED NORTH OF THE AREA BY THEN.
&&
.PREV DISCUSSION... /ISSUED 541 AM CDT THU JUL 5 2012/
AVIATION...12Z KGRI TAF...VFR CONDITIONS ARE EXPECTED TO CONTINUE
AT KGRI FOR THE NEXT 24 HOURS. EXPECT A FEW -SHRAS TO SKIRT THE
TERMINAL THROUGH THE EARLY MORNING HOURS...WITH BOTH CIGS AND
VSBYS EXPECTED TO REMAIN VFR THROUGHOUT. SOUTHERLY WINDS NEAR
10KTS THIS MORNING WILL INCREASE TO NEAR 18KTS BY 17Z...WITH ONLY
A FEW-SCT MID/HIGH LEVEL CLOUDS EXPECTED THROUGH THE AFTERNOON
HOURS.
PREV DISCUSSION... /ISSUED 450 AM CDT THU JUL 5 2012/
SHORT TERM...THROUGH SATURDAY NIGHT. FOR THE NEXT FEW
DAYS...CONCERNS REMAIN PRETTY MUCH THE SAME...AND CENTERED AROUND
HEAT AND FIRE WEATHER. HOWEVER...THE BEGINNING STAGES OF A NOTABLE
RETURN TO COOLER TEMPERATURES WILL GET UNDERWAY BY SATURDAY...WITH
AT LEAST SLIGHT THUNDERSTORM CHANCES IN THE MIX AS EARLY AS
SATURDAY NIGHT. FOR FIRE WEATHER INFO...PLEASE REFER TO THE
SEPARATE SECTION BELOW.
08Z OBJECTIVE SURFACE ANALYSIS REVEALS A TROUGH AXIS/WEAK COLD
FRONT STRETCHED FROM EASTERN CO ACROSS WESTERN/NORTH CENTRAL NEB
INTO SOUTHEAST SD. WITH THE CWA POSITIONED JUST EAST OF THIS
FEATURE...MOST AREAS ARE EXPERIENCING SOUTHERLY BREEZES AROUND 10
MPH...WITH SOME HIGHER GUSTS ESPECIALLY IN KS ZONES. THE
COMBINATION OF BREEZES AND HIGH LEVEL CLOUD COVER IS KEEPING PRE-
DAWN TEMPERATURES WELL UP BETWEEN 73-80 MOST AREAS. AS WAS PRETTY
MUCH EXPECTED 24 HOURS AGO...A NARROW AXIS OF THUNDERSTORMS FLARED
UP DURING THE AFTERNOON/EVENING ALONG THE SURFACE
BOUNDARY...PRIMARILY JUST NORTHWEST OF THE CWA BUT AT LEAST
CLIPPING FAR WESTERN DAWSON COUNTY. EVEN AT THIS HOUR...THIS
FAIRLY WEAK STORM CLUSTER PERSISTS ACROSS SEVERAL SOUTHWEST NEB
COUNTIES...BUT SAFELY OUTSIDE THE CWA. ALOFT...EARLY MORNING WATER
VAPOR IMAGERY AND SHORT TERM MODEL DATA PLACE THE HEART OF THE
EXPANSIVE CENTRAL CONUS MID LEVEL RIDGE AXIS OVER MO...WITH WEAK
SHORTWAVE ENERGY RIDING AROUND THE NORTHWEST PERIPHERY OF THE
RIDGE...ALONG WITH SUPPORT FROM A FAIRLY IMPRESSIVE 40+KT 850MB
LOW LEVEL JET AXIS TEAMING UP TO KEEP THE ONGOING SOUTHWEST NEB
STORMS GOING.
STARTING WITH THE FIRST FEW HOURS EARLY THIS MORNING...MADE A
LAST MINUTE DECISION REGARDING POPS...AS LATEST RADAR TRENDS LEND
LITTLE EVIDENCE OF WIDESPREAD CONVECTION PUSHING BACK EAST-
NORTHEAST TOWARD THE CWA...WHICH IS SOMEWHAT CONTRADICTORY TO THE
QPF/REFLECTIVITY PROGS FROM MODELS SUCH AS THE 06Z NAM AND 05Z
HRRR...WHICH STILL SHOW STORMS POTENTIALLY CLIPPING PARTS OF THE
NORTHERN CWA AS THE LOW LEVEL JET CONVERGENCE ZONE AND THE SURFACE
BOUNDARY START TO LIFT BACK TO THE NORTH. ADDING TO THE
DILEMMA...AS I TYPE THIS...BRAND NEW ISOLATED SHOWER/STORM
DEVELOPMENT IS TAKING PLACE NEAR THE HIGHWAY 6/I-80 CORRIDORS
WITHIN THE LOW LEVEL JET AXIS...WHICH COULD REQUIRE AN EXPANSION
OF AT LEAST SLIGHT CHANCE POPS FOR MORE OF MAINLY THE NORTHERN 1/2
OF THE CWA THAN EARLIER EXPECTED. NO MATTER WHAT...MORNING
CONVECTION SHOULD REMAIN FAIRLY SPARSE IN COVERAGE...AND STRONG TO
SEVERE STORMS SHOULD NOT BE AN ISSUE. HEADING INTO THE AFTERNOON
HOURS...THE ONE WILD CARD FROM THE ONGOING MORNING CONVECTION IS
HOW MUCH...IF EVEN AT ALL...IT SLOWS THE NORTHWARD PROGRESSION OF
THE EFFECTIVE SURFACE WARM FRONT. ALTHOUGH THE SOUTHERN HALF OF
THE CWA SHOULD HAVE NO TROUBLE KEEPING PREVAILING SOUTHERLY
BREEZES...NORTHERN AREAS MAY TEND TO STAY A BIT MORE EAST-
SOUTHEASTERLY FOR A PORTION OF THE DAY. WAS VERY TEMPTED TO PULL
OUT THE SLIGHT CHANCE POP ACROSS THE FAR NORTH DURING THE
AFTERNOON...AS CONSENSUS OF VARIOUS MODELS FOCUSES AFTERNOON
CONVECTION CLOSER TO THE NEB/SD BORDER. HOWEVER...WITH THE LIFTING
BOUNDARY STILL SO CLOSE BY...AND FAIRLY WEAK CAPPING AS DEEP
MIXING COMMENCES...WILL LIKELY PLAY IT SAFE AND LET DAY SHIFT
DECIDE LATER THIS MORNING IF ITS SAFE TO FULLY PULL STORM MENTION
FROM THE FAR NORTHERN CWA. EVEN IF AFTERNOON STORMS WOULD CLIP THE
NORTH...NOT EXPECTING SEVERE IN SUCH A CONTINUED WEAK SHEAR
REGIME...ALTHOUGH SMALL HAIL AND GUSTY WINDS OF 50+ MPH CANNOT BE
RULED OUT. TURNING TO TEMPERATURES...OTHER THAN POSSIBLE
COMPLICATING EFFECTS OF CONVECTIVE OUTFLOW SLOWING THE WARM SURGE
IN NORTHERN COUNTIES...SEE NO REASON TO BELIEVE WHY TEMPS TODAY
SHOULDN/T BE ALMOST IDENTICAL TO THOSE OF YESTERDAY GIVEN VERY
LITTLE CHANGE IN THE LOWER LEVEL THERMAL PROFILE. THUS THE HIGH
TEMP GRID IS ESSENTIALLY A COPY-PASTE FROM YESTERDAY...WITH MOST
OF THE CWA INTO THE 100-105 RANGE...EXCEPT FOR UPPER 90S IN
NORTHEAST ZONES SUCH AS POLK/YORK WHERE DEWPOINTS SHOULD HOLD
HIGHER. ALSO LIKE YESTERDAY...HEAT INDEX VALUES SHOULD EASILY
REACH THE 103-105 RANGE IN MANY AREAS...AND LOCALLY HIGHER
ESPECIALLY IN THE CENTRAL/NORTHEAST. AS A RESULT...AND IN ORDER TO
BETTER COLLABORATE WITH PREVIOUSLY ISSUED HEADLINES BY OAX AND LBF
OFFICES...HAVE GONE AHEAD AND ISSUED A CWA-WIDE HEAT ADVISORY NOT
ONLY FOR THIS AFTERNOON BUT ALSO LASTING THROUGH FRIDAY.
FOR TONIGHT...KEPT OUT ALL STORM MENTION...AS THE SURFACE BOUNDARY
AND ALSO LOW LEVEL JET CONVERGENCE SHOULD FOCUS WELL TO THE NORTH
BY THEN...KEEPING THE BEST STORM CHANCES CLOSER TO THE SD BORDER
AND POINTS NORTH. MADE LITTLE CHANGE TO OVERNIGHT LOW TEMPS...WITH
MOST AREAS BETWEEN 72-76...BUT THIS COULD EASILY BE A FEW DEGREES
TOO COOL IN SOME AREAS.
FOR FRIDAY...AS ALREADY MENTIONED...CONTINUED THE HEAT ADVISORY
GOING THROUGH THE AFTERNOON AND EARLY EVENING...AS ONCE AGAIN JUST
SEE LITTLE REASON TO BELIEVE THAT TEMPERATURES WON/T BE AT LEAST
AS HOT AS YESTERDAY/TODAY. IN FACT...WITH THE NAM SUGGESTING THAT
WINDS WILL TAKE ON MORE OF A SOUTHWESTERLY COMPONENT AHEAD OF AN
APPROACHING COLD FRONT...ACTUAL AIR TEMPERATURES FRIDAY COULD BE
EVEN HOTTER THAN CURRENTLY ADVERTISED. TAKING THE MODEL AT FACE
VALUE...EVEN SEVERAL NEBRASKA COUNTIES COULD MAKE A RUN AT OR
EXCEED 105 DEGREES...WITH 105-108 COMMON IN KANSAS. OF
COURSE...THESE VERY HOT READINGS WOULD ALSO DEPEND ON A MIXING OUT
OF DEWPOINTS DURING THE DAY INTO THE 50S-LOWER 60S. ALTHOUGH AM
NOT GOING FULL BORE WITH THE NAM SOLUTION YET...DID BUMP UP HIGHS
FRIDAY 1-3 DEGREES FROM PREVIOUS FORECAST IN MOST AREAS...WITH THE
MAJORITY OF THE CWA AT LEAST INTO THE 100-104 RANGE. AS FOR STORM
CHANCES...LEFT THE ENTIRE DAY AND EVENING DRY...ALTHOUGH THE
LATEST 06 NAM IS NOW BECOMING MORE SUGGESTIVE THAN PREVIOUS RUNS
OF CONVECTION FIRING ALONG A WELL-DEFINED COLD FRONT NEAR THE
NORTHWEST EDGE OF THE CWA LATE IN THE AFTERNOON/EVENING...SIMILAR
TO WHAT JUST HAPPENED WEDNESDAY. HOWEVER...THE NAM SEEMS TO BE A
BIT OF A FAST OUTLIER ON THE SPEED OF THE INVADING BOUNDARY...WITH
THE ECMWF HANGING CONVECTION MOSTLY JUST OFF TO THE
NORTH/NORTHWEST. WILL HAVE TO KEEP AN EYE ON THIS THOUGH. IF
STORMS ARE ABLE TO FORM IN THE NORTHWEST...A FEW STRONG TO
MARGINALLY SEVERE CELLS CANNOT BE RULED OUT...OWING TO SLIGHTLY
STRONGER FORCING AND DEEP LAYER SHEAR CLIMBING CLOSER TO 30KT.
WILL HOLD OFF FOR NOW ON INTRODUCING ANY STORM MENTION FOR FRIDAY
AFTERNOON/NIGHT...BUT THIS COULD BE INTRODUCED DURING THE NEXT FEW
FORECAST CYCLES IF TRENDS HOLD. WHETHER STORMS FORM OR
NOT...CONFIDENCE IS FAIRLY HIGH THAT THE FIRST LEGITIMATE SUMMER
COLD FRONT IN AWHILE WILL MAKE STEADY PROGRESS INTO THE CWA FRIDAY
NIGHT.
SATURDAY...EVEN THE SLOWER ECMWF SOLUTION BRINGS A COLD FRONT AT
LEAST HALFWAY THROUGH THE CWA...WITH BOTH THE NAM/GFS SUGGESTING
IT WILL MAKE IT ALL THE WAY THROUGH THE CWA INTO CENTRAL
KANSAS...WITH NORTHEAST WINDS CWA-WIDE IN ITS WAKE. OBVIOUSLY THE
SPEED/STRENGTH OF THIS FRONTAL INVASION WILL HAVE A BIG IMPACT ON
HIGH TEMPS...AND CONFIDENCE IS A BIT LOWER THAN USUAL FOR ONLY
BEING A FEW DAYS AWAY...WITH ABOUT A 10 DEGREE SPREAD BETWEEN
MODEL SOLUTIONS. TAKING A CONSENSUS APPROACH...NUDGED DOWN
PREVIOUS FORECAST HIGHS 2-3 DEGREES MOST AREAS...NOW CALLING FOR
HIGHS RANGING FROM ONLY UPPER 80S-LOW 90S IN NEB ZONES...AND MID-
UPPER 90S IN KS. IF THIS PANS OUT...WE SHOULD BE OFFICIALLY DONE
WITH THE PROLONGED ROUGHLY 10-DAY STRETCH OF WELL ABOVE NORMAL
HEAT. ALTHOUGH HAVE CONTINUED TO KEEP THE FORECAST DRY FOR
SATURDAY...POPS MAY EVENTUALLY NEED ADDED HERE AS
WELL...ESPECIALLY IF THE FRONT DOES NOT PASS ALL THE WAY SOUTH OF
THE CWA BY THE AFTERNOON HOURS AS THE NAM SUGGESTS.
BY SATURDAY NIGHT...THE TRANSITION TO A MORE NORTHWESTERLY FLOW
REGIME REALLY STARTS TO SHOW ITS HAND...AS THE CENTER OF THE MID-
UPPER RIDGE AXIS RETROGRADES WEST TO OVER THE ROCKIES VERSUS THE
CURRENT CENTRAL/EASTERN PLAINS POSITION. ALTHOUGH CONFIDENCE IN
THE DETAILS IS LOW...VARIOUS MODELS SUGGEST STORMS COULD IMPACT
PARTS OF THE CWA SAT NIGHT...AND HAVE RE-INTRODUCED A SLIGHT POP
ACROSS MAINLY THE SOUTHWEST 2/3 OF THE CWA FOR NOW.
LONG TERM...STARTING 12Z SUNDAY...THE UPPER LEVEL RIDGE IS
ANTICIPATED TO AMPLIFY OVER THE INTERMOUNTAIN WEST EARLY NEXT WEEK
AS A TROUGH OF LOW PRESSURE DIGS ACROSS THE NORTHEAST. THIS WILL
RESULT IN A GENERALLY NORTHWESTERLY FLOW PATTERN ALOFT ACROSS THE
NORTHERN AND CENTRAL PLAINS FOR SEVERAL DAYS...UNTIL LATE IN THE
PERIOD...WHEN THE RIDGE OVER THE INTERMOUNTAIN WEST BEGINS TO SHIFT
FURTHER EASTWARD.
IN THE LOW LEVELS OF THE ATMOSPHERE...EXPECT THE COLD FRONT THAT IS
FORECAST TO REACH THE LOCAL AREA ON SATURDAY...TO LINGER NEAR THE
KS/NE STATE LINES ON SUNDAY...EVENTUALLY PUSHING SOUTH OF THE LOCAL
AREA BY SUNDAY AFTERNOON OR MONDAY. BOTH EC AND GFS TRACK THIS FRONT
ACROSS THE LOCAL AREA AND TO THE SOUTH BY LATE SUNDAY EVENING/EARLY
MONDAY MORNING...AND DUE TO THIS SLIGHT VARIATION IN
TIMING...DECIDED TO KEEP SOME SMALL MENTION OF POPS INTO THE DAY
MONDAY...WITH SKIES THEN CLEARING AND DRY WEATHER EXPECTED
THEREAFTER.
WHILE THERE WILL BE A CHANCE FOR SOME MUCH NEEDED PRECIPITATION WITH
THIS PASSING BOUNDARY...INSTABILITY AND SHEAR BOTH APPEAR VERY
MARGINAL...AND WIDESPREAD SEVERE WEATHER IS NOT ANTICIPATED AT THIS
TIME. AT THIS POINT...IT APPEARS COOLING TEMPERATURES WILL BE AS
WELCOME AS RAIN CHANCES OVER THE UPCOMING WEEKEND...WITH 850 MB
TEMPS FORECAST TO DROP AS MUCH AS 10C DEPENDING ON WHICH MODEL YOU
ARE LOOKING AT. WITH COOLER TEMPS ALOFT...SOME ANTICIPATED CLOUDS
AND AT LEAST SPOTTY RAINFALL...WENT AHEAD AND LOWERED TEMPS SUNDAY
AFTERNOON BELOW SEASONAL NORMS FOR THE FIRST TIME IN A WHILE...WITH
CONTINUED SEASONABLY COOL WEATHER THEN ANTICIPATED THROUGH THE END
OF NEXT WEEK. BESIDES LOWERING TEMPS A BIT ON SUNDAY AND TRIMMING
POPS A SMALL AMOUNT MONDAY AFTERNOON...NO OTHER SIGNIFICANT CHANGES
NECESSARY TO BLENDED MODEL SOLUTIONS THIS MORNING.
FIRE WEATHER...ALTHOUGH THE COMBINATION OF RELATIVE HUMIDITY
DROPPING TO AROUND 20 PERCENT AND SUSTAINED WINDS NEAR 20
MPH/GUSTS AROUND 25 MPH WILL AGAIN PROMOTE AT LEAST NEAR-CRITICAL
FIRE DANGER ACROSS SEVERAL SOUTHERN COUNTIES THIS
AFTERNOON...OPTED TO HOLD OFF ON A FORMAL RED FLAG WARNING THIS
TIME AROUND...AS CONDITIONS SHOULD BE VERY SIMILAR TO
YESTERDAY...DURING WHICH RED FLAG CRITERIA STRUGGLED TO
MATERIALIZE FOR 3 OR MORE HOURS. HOWEVER...IT COULD STILL BE A
CLOSE CALL...AND SOMETHING THAT DAY SHIFT WILL HAVE TO MONITOR.
DESPITE THE LACK OF A FORMAL RED FLAG WARNING AT THIS
TIME...EXTREME FIRE DANGER WILL BE HIGHLIGHTED FOR SEVERAL
COUNTIES IN THE GRASSLAND FIRE DANGER PRODUCT...AND WILL CONTINUE
TO MENTION IN THE HAZARDOUS WEATHER OUTLOOK. TURNING TO
FRIDAY...THERE MIGHT ACTUALLY BE GREATER FIRE CONCERNS ON THIS
DAY...AS WINDS TURN MORE SOUTHWESTERLY AND SPREAD SUB-20 PERCENT
RH POTENTIAL FARTHER NORTHEAST...POTENTIALLY INTO ALL AREAS
SOUTHWEST OF A LEXINGTON-BELOIT LINE. IT APPEARS THE LIMITING
FACTOR FOR EVENTUAL RED FLAG ISSUANCE COULD BE WIND SPEEDS...AS
CURRENTLY HAVE SUSTAINED SPEEDS AVERAGING CLOSER TO 15 MPH VERSUS
20 MPH. IF WINDS WERE EXPECTED TO BE ROUGHLY 5 MPH HIGHER...WOULD
HAVE CONSIDERED ISSUING A FIRE WEATHER WATCH...AND DAY SHIFT WILL
HAVE TO TAKE ANOTHER LOOK TO SEE IF AT LEAST A WATCH MIGHT BE
WARRANTED FOR FRIDAY. FORTUNATELY...THE INVASION OF A COOLER
AIRMASS FOR SATURDAY AND THE NEXT SEVERAL DAYS THEREAFTER SHOULD
AT LEAST EASE UP THE UNSEASONABLY HIGH FIRE DANGER WE HAVE HAD
LATELY.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...HEAT ADVISORY FROM NOON TODAY TO 9 PM CDT FRIDAY FOR NEZ039>041-
046>049-060>064-072>077-082>087.
KS...HEAT ADVISORY FROM NOON TODAY TO 9 PM CDT FRIDAY FOR KSZ005>007-
017>019.
&&
$$
UPDATE/SHORT TERM/FIRE WEATHER...PFANNKUCH
LONG TERM/AVIATION...ROSSI
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1130 AM EDT THU JUL 5 2012
.SYNOPSIS...
AN UPPER LEVEL RIDGE EXTENDING EASTWARD FROM THE CENTRAL MISSISSIPPI
RIVER VALLEY TOWARD THE CAROLINAS WILL RESULT IN ABOVE NORMAL
TEMPERATURES TODAY THROUGH THE UPCOMING WEEKEND...WITH A CHANCE FOR
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON
AND EVENING HOURS EACH DAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1130 AM THURSDAY...
OVERVIEW:
NORTHWEST FLOW ALOFT WILL PREVAIL OVER THE CAROLINAS THROUGH
TONIGHT...ON THE EASTERN PERIPHERY OF AN UPPER LEVEL RIDGE CENTERED
OVER THE CENTRAL MS RIVER VALLEY. 14Z WV IMAGERY AND RUC DATA
INDICATED MULTIPLE MID/UPPER LEVEL DISTURBANCES EMBEDDED WITHIN NW
FLOW ALOFT OVER THE MID-ATLANTIC AND CAROLINAS.
TEMPERATURES:
THE 12Z GSO RAOB INDICATED A 1000-850 MB THICKNESS OF 1434 METERS
THIS MORNING. THIS IS CONSISTENT WITH THE LATEST MODEL GUIDANCE...
WHICH CONTINUES TO INDICATE 1000-850 MB THICKNESSES IN VICINITY OF
1455 METERS BY 00Z...ROUGHLY 10-15 METERS HIGHER THAN YESTERDAY.
MODEL GUIDANCE INDICATES H85 TEMPS IN THE 21-23C RANGE THIS
AFTERNOON...GENERALLY CONSISTENT WITH UPSTREAM CONDITIONS PER 14Z
SPC MESOANALYSIS (THOUGH COOLER TEMPS ARE PRESENT OVER WV IN ASSOC/W
MCS REMNANTS). HIGHS YESTERDAY RANGED FROM 95-98F IN MOST
LOCATIONS...RDU AN EXCEPTION AT 101F. BASED ON YESTERDAY`S TEMPS AND
A 10-15 METER INCREASE IN THICKNESSES...EXPECT HIGHS IN VICINITY OF
100F TODAY...THOUGH ISOLD/SCT CONVECTION MAY PREVENT HIGHS FROM
EXCEEDING THE MID/UPPER 90S IN SOME LOCATIONS. DECIDED TO INCREASE
THE HIGH AT RDU TO 102F BASED ON YESTERDAY`S READING. WILL DECREASE
HIGHS A FEW DEGREES LOWER THAN WHAT THICKNESSES SUGGEST IN THE FAR
NW PIEDMONT WHERE OUTFLOW FROM MCS REMNANTS (AND NEWLY DEVELOPED
CONVECTION NEAR BLUEFIELD WV) MAY AFFECT TEMPS BY EARLY/MID
AFTERNOON. H85 DEWPOINTS RANGED FROM 13-15C (55-60F) ACROSS THE AREA
AT 14Z...AND SHOULD REMAIN IN THAT VICINITY THROUGH THE AFTERNOON.
GIVEN STRONG HEATING AND MIXING UP TO AT LEAST H85...ANTICIPATE THAT
DEWPOINTS WILL MIX OUT INTO THE LOWER/MID 60S IN THE NORTHERN AND
WESTERN PIEDMONT. IN THE SANDHILLS AND COASTAL PLAIN ON THE EASTERN
PERIPHERY OF THE LEE TROUGH...EXPECT DEWPOINTS WILL LIKELY REMAIN IN
THE UPPER 60S TO LOWER 70S GIVEN RELATIVELY HIGHER H85 DEWPOINTS IN
THE PRESENCE OF SHALLOW LOW-LEVEL CONVERGENCE AND MOISTURE POOLING.
EXPECT OVERNIGHT LOWS A BIT WARMER THAN THIS MORNING DUE TO AIRMASS
MODIFICATION...IN THE LOWER/MID 70S...OR 72-75F.
HEAT INDICES/HEAT ADVISORY:
WITH THE ABOVE T/TD DISCUSSION IN MIND...ANTICIPATE MAX HEAT INDICES
BETWEEN 105-110F IN THE ADVISORY AREA...WITH HEAT INDICES
APPROACHING 105F IN THE TRIANGLE...AND GENERALLY 100-105F IN THE
WESTERN PIEDMONT. DESPITE MAX HEAT INDICES FORECAST NEAR 105F IN
WAKE/FRANKLIN/WARREN COUNTIES...DECIDED NOT TO EXPAND THE HEAT
ADVISORY TO INCLUDE THOSE COUNTIES GIVEN A FAIR AMOUNT OF
UNCERTAINTY W/REGARD TO DEWPOINTS ALONG/WEST OF HWY 1 AND CONVECTIVE
EVOLUTION MID/LATE AFTERNOON.
PRECIPITATION CHANCES/SEVERE THREAT:
WILL INCREASE PRECIP CHANCES IN THE WESTERN PIEDMONT TO 30% EARLY
THIS AFTERNOON GIVEN PRE-EXISTING CONVECTION DEVELOPING IN ASSOC/W
DECAYED MCS REMNANTS JUST SOUTH OF BLUEFIELD WV...THOUGH THE BULK OF
THIS ACTIVITY MAY AFFECT THE NORTHWEST NC FOOTHILLS/MOUNTAINS.
OTHERWISE THE PREVIOUS FCST WILL REMAIN UNCHANGED AT THIS TIME. SPC
HAS INCLUDED THE WESTERN PIEDMONT IN A SLIGHT RISK FOR SEVERE
WEATHER. A MORE DETAILED DISCUSSION ON PRECIP CHANCES AND THE
POTENTIAL FOR SEVERE WEATHER TODAY WILL BE ISSUED BY 1 PM. -VINCENT
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 230 AM THURSDAY...
FOR FRIDAY/FRIDAY NIGHT: CONTINUED WARM AND HUMID. THE SURFACE FRONT
IS EXPECTED TO EXTEND FROM EASTERN AND NORTHERN VA NORTHWARD THROUGH
THE CENTRAL APPALACHIANS THEN WESTWARD ACROSS MI AND THE UPPER
MIDWEST EARLY FRIDAY... WITH THE SURFACE LEE TROUGH PERSISTING
THROUGH CENTRAL NC. THE NAM/GFS SUGGEST THAT A SUBTLE UPPER LEVEL
SHEAR AXIS WILL DROP SOUTHWARD THROUGH NC BY EARLY AFTERNOON. WHILE
THIS MIGHT BE A BYPRODUCT OF UPSTREAM MCS ACTIVITY... THE SUBPAR
PERFORMANCE OF BOTH MODELS WITH THE CURRENT CONVECTION NEAR THE
OH/WV BORDER INTO SW PA GREATLY REDUCES CONFIDENCE IN THE SUBSEQUENT
MODEL DETAILS. WHILE IT IS CERTAINLY REASONABLE TO EXPECT THAT WE
MIGHT BE AFFECTED BY AN UPSTREAM MCV SOMETIME FRIDAY BASED ON THE
ONGOING LONGWAVE PATTERN OVER THE CONUS... THE MID LEVEL RIDGE
CENTERED OVER NRN MISSOURI WILL STEADILY EXPAND EASTWARD THROUGH THE
MIDATLANTIC REGION THROUGH FRIDAY NIGHT... RESULTING IN AROUND A
20-30 METER MID LEVEL HEIGHT RISE OVER NC AND LIKELY CAUSING A
SOUTH-SOUTHWESTWARD DEFLECTION IN MOVEMENT OF ANY SUCH MCV TOWARD
THE SRN APPALACHIANS / WRN NC... WHERE 850-500 MB LAPSE RATES ARE
EXPECTED TO BE 6.75-7.0 C/KM. HOWEVER... INSTABILITY WILL REMAIN
MODERATE TO BORDERLINE STRONG IN THE AFTERNOON AND EVENING OVER
CENTRAL NC WITH MLCAPE OF 1500-2800 J/KG... AND WITH MARGINAL BUT
SUFFICIENT DEEP LAYER SHEAR NEAR 20 KTS. SO EVEN IN THE ABSENCE OF
CONSIDERABLE DYNAMIC SUPPORT FOR ORGANIZATION OF CONVECTION... WE
SHOULD STILL SEE ISOLATED TO SCATTERED COVERAGE WITH PRECIP WATER
VALUES EXPECTED TO REACH 1.8-1.9 INCHES... ABOUT 150% OF NORMAL.
THIS SHOULD RESULT IN ONLY MINOR CHANGES TO THE EARLIER FORECAST. WE
MAY SEE A STRONG STORM OR TWO PRODUCING GUSTY WINDS AS WELL AS SOME
HAIL GIVEN THAT CAPE IN THE -10C TO -30C IS EXPECTED TO EXCEED 1000
J/KG WITH NORMALIZED CAPE OVER 0.20 M/S2. LOW LEVEL THICKNESSES --
WHICH ARE PROJECTED TO CHANGE VERY LITTLE DAY-TO-DAY THROUGH THE
UPCOMING WEEKEND -- POINT TO HIGHS ONCE AGAIN A FEW OF DEGREES
EITHER SIDE OF 100 ACROSS THE AREA... WHICH CLOSELY FOLLOWS
PERSISTENCE. SURFACE DEW POINT FORECAST INDICATE ANOTHER HEAT
ADVISORY IS NEEDED FOR ALL OF CENTRAL NC EXCLUDING THE TRIAD REGION.
MODELS INDICATE LINGERING ELEVATED INSTABILITY OVERNIGHT... BUT WITH
PROJECTIONS OF WANING PRECIP WATER AND CONFLUENT MID-UPPER LEVELS...
WE SHOULD SEE A 10 PERCENT OR LOWER COVERAGE OF NIGHTTIME PRECIP...
SO WILL KEEP THE FORECAST DRY OVERNIGHT. LOWS 71-76.
FOR SATURDAY/SATURDAY NIGHT: STILL HOT WITH EVEN LOWER COVERAGE OF
CONVECTION. AS THE MID LEVEL RIDGE AXIS CONTINUES TO BUILD EASTWARD
THROUGH NC... MID LEVEL LAPSE RATES SLIP TO JUST 6.0-6.25 C/KM WITH
DRYING ALOFT. LOW LEVEL FLOW STRENGTHENS FROM THE SOUTHWEST DUE TO
THE INCREASING MSLP GRADIENT BETWEEN THE SURFACE HIGH OFF THE
SOUTHEAST COAST AND THE SOUTHWARD-DRIFTING SYNOPTIC COOL FRONT
DROPPING TOWARD THE OHIO VALLEY... AND WE SHOULD SEE A WEAKENING OF
THE LEE TROUGH WITH DIMINISHING MID LEVEL WINDS. WITH CONTINUED
STRONG SURFACE HEATING... WILL NOT GO ENTIRELY DRY BUT WILL RESTRICT
PRECIP CHANCES TO EASTERN SECTIONS WHERE HIGHER PRECIP WATER AND
SURFACE DEW POINTS WILL RESIDE... AND WILL CONFINE ISOLATED
THUNDERSTORMS TO MID AFTERNOON INTO THE EVENING. HIGHS AGAIN 98-102.
PREDICTED AFTERNOON DEW POINTS SHOULD SUPPORT YET ANOTHER DAY OF
HIGH HEAT INDEX VALUES... AND MORE HEAT ADVISORIES MAY BE
REQUIRED... ALTHOUGH THE SOUTHWEST WINDS MAY ALLOW FOR GREATER
MIXING OUT OF DEW POINTS WHICH COULD SUPPRESS HEAT INDICES A BIT.
BREEZES STAYING UP OVERNIGHT SHOULD KEEP TEMPS ELEVATED OVERNIGHT...
THUS ANTICIPATE WARMER LOWS OF 74-78. -GIH
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 250 AM THURSDAY...
FOR SUNDAY/SUNDAY NIGHT: THE MID LEVEL RIDGE WILL CONTINUE TO EXTEND
ACROSS NC BUT WILL HAVE BECOME STRETCHED AND WEAKENED WITH LOWERING
HEIGHTS OVER THE MIDATLANTIC... FORESHADOWING A PATTERN CHANGE AS A
CANADIAN VORTEX DEEPENS OVER THE BORDER OF QUEBEC WITH LABRADOR. AS
THE LONGWAVE TROUGH BEGINS TO AMPLIFY OVER THE NORTHEAST QUARTER OF
THE COUNTRY... THE SURFACE COOL FRONT SHOULD DROP SOUTHWARD TOWARD
THE VA/NC STATE LINE... ALTHOUGH HOW FAR SOUTHWARD IS DIFFICULT TO
PINPOINT AT THIS RANGE. BUT GFS/ECMWF THICKNESSES REMAIN QUITE
HIGH... AND EXPECT THE HEAT TO HOLD FOR ONE MORE DAY... WITH JUST
ISOLATED STORM CHANCES AS THE MID LEVELS REMAIN RATHER WARM AND DRY.
HIGHS AGAIN CLOSE TO 100 WITH MORNING THICKNESSES IN THE 1430-1435
METER RANGE. LOWS IN THE MID-UPPER 70S WITH LOW LEVEL MOISTURE
LIKELY TO POOL AHEAD OF THE FRONT.
FOR MONDAY THROUGH WEDNESDAY: AN END TO THE HEAT WAVE MAY BE IN
SIGHT. THE FRONT IS EXPECTED TO DROP INTO THE REGION MONDAY AS THE
LONGWAVE TROUGH DIGS SOUTHWARD THROUGH THE APPALACHIANS AND MID
SOUTH. INCREASING DEEP LAYER SHEAR... RISING MOISTURE THROUGH THE
COLUMN... AND DYNAMIC FORCING FOR ASCENT SHOULD RESULT IN A GOOD
CHANCE OF SHOWERS AND STORMS EARLY IN THE WORK WEEK. THE SOUTHERN
PORTION OF THE LONGWAVE TROUGH MAY WEAKEN A BIT TOWARD WEDNESDAY BUT
SHOULD STILL HOLD OVER OR JUST WEST OF THE FORECAST AREA... ROUGHLY
ALONG THE SPINE OF THE APPALACHIANS. WITH THIS PATTERN... THE
SURFACE FRONT IS LIKELY TO STALL OUT OVER THE CENTRAL CAROLINAS WITH
A GENERAL WEAKENING TREND IN BOTH THE MSLP AND LOW LEVEL WIND
FIELDS... TYPICAL FOR JULY IN NC. THIS SHOULD LEAVE US WITHIN A
STEADY STREAM OF WEAK MID LEVEL PERTURBATIONS WITH A CONTINUED
TAPPING OF LOW AND MID LEVEL MOISTURE FROM THE GULF. EXPECT AT LEAST
SCATTERED SHOWERS AND STORMS EACH DAY. THICKNESSES HEAD BACK DOWN TO
SEASONAL NORMALS ALTHOUGH THIS MAY BE DUE IN PART TO INCREASED
CLOUDINESS... INDICATIVE OF HIGHS NEAR OR JUST UNDER NORMAL HIGHS
BUT WITH ABOVE-NORMAL LOWS. -GIH
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 720 AM THURSDAY...
A FEW LOCATIONS ARE REPORTING 4-6SM VSBYS THIS MORNING...BUT THEY
ARE VERY ISOLATED...WITH MOST LOCATIONS REPORTING VFR CONDITIONS.
SCATTERED STORMS WILL BE POSSIBLE AGAIN THIS AFTERNOON ALONG AND
SOUTH OF A PERSISTENT PIEDMONT TROUGH OVER CENTRAL NC...AND POSSIBLY
OVER THE WESTERN PIEDMONT AS AN UPPER LEVEL DISTURBANCE HELPS
TRIGGER STORMS IN OVER THE HIGHER TERRAIN. HOWEVER...CONFIDENCE IN
ANY IMPACTS AT TAF SITES REMAINS TOO LOW FOR MENTION OF THUNDER IN
THE CURRENT TAF PACKAGE.
OUTLOOK....
PREDOMINATELY VFR CONDITIONS ARE EXPECTED THROUGH THE WEEKEND AS A
STRONG UPPER LEVEL RIDGE BUILDS BACK EAST OVER THE REGION. A FEW
ISOLATED THUNDERSTORMS WILL ALSO BE POSSIBLE DURING THIS PERIOD. AN
APPROACHING COLD FRONT SHOULD BRING A BETTER CHANCE OF
SHOWERS/STORMS AND ADVERSE AVIATION CONDITIONS EARLY NEXT WEEK.
&&
.CLIMATE...
HIGH TEMPERATURE RECORDS AND YEAR RECORD LAST SET.
RALEIGH-DURHAM... GREENSBORO...
07/05 102 1999 98 1990
07/06 102 1999 100 1977
07/07 102 2010 101 1977
07/08 103 1977 102 1977
FAYETTEVILLE...
07/05 101 2002
07/06 99 1990
07/07 103 2010
07/08 102 1977
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY FROM 11 AM THIS MORNING TO 9 PM EDT THIS EVENING
FOR NCZ011-027-028-042-043-077-078-085-086-088-089.
HEAT ADVISORY FROM 11 AM TO 8 PM EDT FRIDAY FOR NCZ008>011-
025>028-040>043-074>078-083>086-088-089.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT
SHORT TERM...HARTFIELD
LONG TERM...HARTFIELD
AVIATION...KRR/SMITH
AREA FORECAST DISCUSSION
NWS PUEBLO CO
318 PM MDT THU JUL 5 2012
.SHORT TERM...
(TONIGHT AND FRIDAY)
SOUTHERLY WINDS HAVE INCREASED ACROSS THE PLAINS AND VALLEYS WITH
GUSTS TO AROUND 30 KTS ACROSS THE FAR EASTERN PLAINS. THIS
SOUTHERLY FETCH IS STILL TAPPING MODERATE DEW POINTS IN 50S TO THE
SOUTH OF THE REGION...SO IN SPITE OF THE MIXING...SFC DEW POINTS
HAVE REMAINED IN THE UPPER 40S AND 50S OUT EAST. SO FAR THIS HAS
KEPT RELATIVE HUMIDITIES ABOVE THE CRITICAL 15 PERCENT THRESHOLD FOR
FIRE WEATHER CONCERNS ACROSS THE PLAINS. POCKETS OF DRIER AIR HAVE MIXED
DOWN INTO THE LOWER ELEVATIONS WITH DEW POINTS IN THE 30S ACROSS THE
UPPER ARKANSAS RIVER VALLEY OF CHAFFEE AND LAKE COUNTIES AS WELL AS
THE WET MOUNTAIN VALLEY...WITH UPPER 30S AND 40S ALONG THE I-25
CORRIDOR AND CENTRAL AND EASTERN FREMONT COUNTIES.
MEANWHILE...EMBEDDED MONSOON MOISTURE PLUME EXTENDS ACROSS THE
WESTERN PORTIONS OF THE STATE WITH MOST APPARENT EMBEDDED
WAVE LIFTING NORTHWARD ACROSS UT. FOR THE REMAINDER OF
TONIGHT...EXPECT SCATTERED TO NUMEROUS THUNDERSTORMS OVER THE
MOUNTAINS...WITH GREATEST COVERAGE ALONG THE CONTINENTAL DIVIDE
WHERE PRECIP WATERS ARE RUNNING THE HIGHEST. LOCALLY HEAVY RAINFALL
WILL BE THE PRIMARY THREAT ALONG WITH LIGHTNING. GUSTY WINDS UP TO
40 MPH WILL BE POSSIBLE ACROSS THE VALLEYS. HRRR CONTINUES TO
DEVELOP HIGH BASED THUNDERSTORMS ALONG THE SFC TROF AXIS ACROSS SE
CO...SO HAVE NUDGED SOME ISOLATED POPS A TOUCH FARTHER EAST.
SOUNDINGS FROM THE I-25 CORRIDOR EASTWARD KEEP THUNDERSTORMS MORE
HIGH BASED WITH LCLS AROUND H6. HRRR DEVELOPS SOME ISOLATED TO
SCATTERED CONVECTION NEAR THE WALDO CANYON BURN SCAR BETWEEN 4-5 PM
WITH AROUND .25 INCH OF RAINFALL POSSIBLE SHOULD IT IMPACT THE BURN
SCAR. WITH SOUTHERLY FLOW AROUND 10-20 KTS THROUGH THE LAYER...STORM
MOTIONS SHOULD BE SUFFICIENT TO LIMIT THE THREAT FOR FLASH FLOODING
ON THE BURN SCAR...AND THESE MODEL PREDICTED AMOUNTS LOOK IN THE
BALL PARK. THUNDERSTORMS DIE OFF DIURNALLY FOR MOST AREAS...THOUGH WILL
HANG ON TO SOME ISOLATED -TSRA ACROSS WESTERN AREAS BENEATH THE
MONSOON PLUME.
ON FRIDAY...COLD FRONT WILL SHIFT SOUTHWARD INTO EL PASO COUNTY
DURING THE AFTERNOON...INCREASING PRECIPITABLE WATERS AS DEW POINTS
BEHIND THE BOUNDARY RISE INTO THE LOWER 50S. DEEPER MONSOON
MOISTURE PLUME RESIDES ACROSS THE CONTINENTAL DIVIDE...HOWEVER WITH
DEW POINTS ACROSS NORTHEAST CO CURRENTLY IN THE 50S...SEEMS REASONABLE THAT
LOW LEVEL MOISTURE WILL INCREASE MORE RAPIDLY BEHIND THE FRONT ON
FRIDAY...COMPARED TO THE SCENARIO THAT PLAYED ON WEDNESDAY. THIS
RAISES CONCERNS FOR FLASH FLOODING ON THE WALDO CANYON BURN SCAR AS
THE HIGHER MOISTURE CONTENT OF THE ATMOSPHERE SHOULD SUPPORT HEAVIER
RAINFALL RATES. WITH THE FRONT PROGGED TO LIE UP ACROSS THIS
REGION...THERE IS MORE LIKELY TO BE A FOCUS MECHANISM FOR
THUNDERSTORM GENERATION IN THIS AREA AS WELL...AND A FLASH FLOOD WATCH
MAY BE NEEDED IF FUTURE MODEL RUNS CONTINUE TO INDICATE SUFFICIENT
MOISTURE WILL BE AVAILABLE IMMEDIATELY BEHIND THE FRONT.
PROBABILITY LOOKS HIGHER FOR THIS TO OCCUR ON FRIDAY VERSUS
WEDNESDAY...BUT WOULD LIKE TO SEE THIS SCENARIO GET RESOLVED BY
HIGHER RESOLUTION SHORT RANGE MODELS (WRF...RUC13...HRRR) BEFORE
PULLING THE TRIGGER ON THE FLASH FLOOD WATCH. AS WE HAVE SEEN THE
PAST FEW DAYS...A LOT WILL DEPEND ON MESOSCALE FORECASTING...AND
WILL DEFER THIS DECISION TO LATER SHIFTS. HOWEVER...PEOPLE IN AND
NEAR THE WALDO CANYON BURN SCAR SHOULD MAINTAIN A HEIGHTENED
AWARENESS FOR THE POTENTIAL OF FLASH FLOODING AS WE TRANSITION INTO
MOISTER ENVIRONMENT AS THE WEEKEND APPROACHES.
ELSEWHERE...SCATTERED TO NUMEROUS THUNDERSTORMS CAN BE EXPECTED
ACROSS THE MOUNTAIN AREAS WITH MORE ISOLATED THUNDERSTORMS ACROSS
THE PLAINS TO THE SOUTH OF THE FRONT. HEAVY RAIN AND LIGHTNING WILL
BE THE PRIMARY STORM THREATS OVER THE MOUNTAINS...WITH MORE OF A
GUSTY WIND POTENTIAL ALONG WITH LIGHT TO MODERATE RAINFALL ACROSS
THE REMAINDER OF THE SOUTHEAST PLAINS. -KT
.LONG TERM...
(FRIDAY NIGHT THROUGH THURSDAY)
...LOCALLY HEAVY RAINFALL POSSIBLE INTO EARLY NEXT WEEK...
FRIDAY NIGHT-SATURDAY NIGHT... FRIDAY NIGHT INTO EARLY SATURDAY WILL BE A
TRANSITION PERIOD OVER THE CWA. THE GFS/NAM12 ARE IN GOOD AGREEMENT
OF A SHORTWAVE PASSING NORTH OF THE FORECAST AREA FRIDAY NIGHT AND
DROPPING A COLD FRONT THROUGH EASTERN COLORADO BY 12Z SATURDAY
MORNING. BOTH MODELS ADVECT PLENTY OF MOISTURE INTO THE REGION
BEHIND THE FRONT...SHOWING DEWPOINTS OF MID 50S TO NEAR 60 BEHIND
THE FRONT BY 15Z SATURDAY. MODELS SHOW WEAK EASTERLY FLOW AND
WIDESPREAD SHOWERS AND THUNDERSTORMS OVER THE REGION BY 00Z SUNDAY. MODEL
QPF MAY BE A BIT OVERDONE AS A DISTINCT TRIGGER IS HARD TO IDENTIFY
GIVEN CURRENT MODEL DATA. HOWEVER...WITH PLENTY OF MOISTURE IN
PLACE...WEAK UPSLOPE FLOW...AND HARD TO TIME WEAK SHORTWAVES IN THE
FLOW PASSING OVERHEAD...CONVECTIVE INITIATION WILL BE POSSIBLE.
LOCALLY HEAVY RAIN WILL BE POSSIBLE AS UPPER LEVEL FLOW WILL BE WEAK
ACROSS THE REGION. 500MB WINDS ARE PROGGED TO BE...AT BEST...
5-10KTS SATURDAY AND SUNDAY AFTERNOON. HIGH RESOLUTION SHORT RANGE
MODELS WILL NEED TO BE EVALUATED FRIDAY NIGHT/EARLY SATURDAY
MORNING TO GET A MORE DETAILED PICTURE OF HOW MUCH PRECIPITATION
MAY FALL ACROSS THE REGION...ESPECIALLY IN AND AROUND THE WALDO
CANYON FIRE BURN SCAR.
BESIDES PRECIPITATION...ANOTHER SIGNIFICANT CHANGE WILL BE
TEMPERATURES RETURNING TO AVERAGE OR JUST BELOW AVERAGE LEVELS
ACROSS THE FORECAST AREA. MODELS LOWER 700MB TEMPERATURES FROM
RECENT 18-20C READINGS TO THE LOWER TEENS BEHIND THE FRONT FRIDAY
MORNING. 700MB TEMPERATURES WILL CONTINUE TO FALL THROUGH
SATURDAY...BOTTOMING OUT IN THE 8-10C RANGE SUNDAY. THE HIGHEST
TEMPERATURES CURRENTLY FORECAST FOR THE EASTERN PLAINS IS ONLY 87F
ACROSS THE EASTERN PLAINS ON SUNDAY...ENDING A LONG RUN OF 90-100+
TEMPERATURES IN THAT AREA.
SUNDAY AND MONDAY...
THE CENTER OF THE UPPER LEVEL HIGH PRESSURE THAT HAS BEEN CENTERED
OVER THE PLAINS THE PAST FEW DAYS WILL BEGIN TO RETROGRADE TOWARDS
THE FOUR CORNERS REGION SUNDAY MORNING WITH THE RIDGE AXIS BEING
CENTERED NEAR UTAH BY SUNDAY NIGHT. THIS WILL HELP MAINTAIN WEAK
STEERING CURRENTS ALOFT AND WEAK UPSLOPE FLOW ACROSS THE FORECAST
AREA. SCATTERED SHOWERS AND THUNDERSTORMS WILL AGAIN DEVELOP BY
LATE MORNING AND INCREASE IN COVERAGE THROUGHOUT THE AFTERNOON.
LOCALLY HEAVY RAINS WILL AGAIN BE POSSIBLE IN THE MOUNTAINS...I-25
CORRIDOR (INCLUDING THE WALDO CANYON BURN SCAR.)...AND THE EASTERN PLAINS.
TUESDAY-THURSDAY...
THE UPPER LEVEL HIGH TO THE NORTHWEST WILL PRODUCE WEAK
NORTHEASTERLY WINDS AT 500MB BEGINNING EARLY TUESDAY. THIS WILL
ADVECT SOME RELATIVELY DRIER AIR INTO EASTERN PARTS OF THE FORECAST
AREA. ENOUGH MOISTURE WILL REMAIN OVER THE HIGHER ELEVATIONS TO KEEP
AFTERNOON PULSE THUNDERSTORMS IN THE FORECAST THROUGH THURSDAY...BUT
COVERAGE SHOULD REMAIN LIMITED TO THE CENTRAL AND SOUTHWEST
MOUNTAINS WITH LITTLE TO NO PRECIPITATION EXPECTED OVER THE I-25
CORRIDOR OR EASTERN PLAINS. -PJC
&&
.AVIATION...
SOUTH TO SOUTHWEST WINDS WILL CONTINUE AT TAF SITES IN THE 12-24 KT
RANGE THROUGH 02-03Z. VFR CIGS AND GUSTIER WINDS UP TO 35 KTS WILL
BE POSSIBLE NEAR -TSRA THIS EVENING. MOST LIKELY TAF SITE TO GET
IMPACTED BY THUNDERSTORMS WILL BE AT KALS. WILL ALSO MAINTAIN VCTS
AT KCOS...THOUGH THIS LOOKS MOST LIKELY TO OCCUR AFTER 21-22Z.
THUNDERSTORMS WILL DECREASE AFTER 02Z. ON FRIDAY...NORTHERLY WINDS
BEHIND A COLD FRONT WILL AFFECT KCOS BETWEEN 09-12Z...AND AT KPUB BY
15Z. -TSRA WILL BE MORE LIKELY TO AFFECT THE KCOS TAF SITE FRIDAY
AFTERNOON BEHIND THE COLD FRONT AS WINDS SHIFT AROUND FROM THE
NORTHEAST TO EAST. VFR TO BRIEF MVFR CIGS...WITH LOCALLY HEAVY RAINFALL
WILL BE POSSIBLE. KALS WILL ALSO SEE THE POTENTIAL FOR
THUNDERSTORMS FRIDAY AFTERNOON...THOUGH WINDS LOOK LIGHTER IN THE
10-15 KT RANGE. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
31/81
AREA FORECAST DISCUSSION...UPDATED
NWS PUEBLO CO
1139 AM MDT THU JUL 5 2012
.UPDATE...
FORECAST GENERALLY ON TARGET...THOUGH DID BUMP UP TIMING OF -TSRA
FOR THE SE MTS WHERE THEY STARTED FIRING AT AROUND 16Z. SFC DEW
POINTS ARE HIGHER TODAY THAN THEY WERE YESTERDAY ACROSS THE
PLAINS/I-25 CORRIDOR...THOUGH MODEL SOUNDINGS STILL SHOW SOME
DRYING ALOFT WHICH IS HELPING TO BRING PRECIP WATERS DOWN SOME.
LOCALLY HEAVY RAIN WILL BE THE PRIMARY THREAT WITH THUNDERSTORMS
TODAY...THOUGH WITH SOUTHERLY WINDS 10-15 KTS THROUGH THE
SOUNDINGS STORMS SHOULD MOVE SOME WHICH MAY MITIGATE THREAT FOR
FLASH FLOODING ON BURN SCARS. ALSO APPEAR TO BE LACKING A FOCUS
MECHANISM (FRONTAL BOUNDARY...UPSLOPE FLOW...ETC) TO HELP ANCHOR
STORMS TO THE MOUNTAINS. 13Z HRRR PRINTS OUT SOME BULLS EYES OF
AROUND .25 OF LIQUID FROM -TSRA IN AND NEAR THE WALDO BURN
SCAR...BUT THESE MOVE FROM RUN-TO-RUN AS EXPECTED. THUS...ALTHOUGH
MOISTURE APPEARS A BIT BETTER TODAY...STILL THINK LOCALIZED FLASH
FLOOD THREAT ON THE WALDO IS STILL LOW. BY FAR BETTER MOISTURE AND
BETTER CHANCES FOR HEAVIER RAIN WILL BE OUT ALONG THE CONTDVD...SO
THOSE AREAS WILL BE MONITORED CLOSELY THROUGH THE AFTERNOON AND
EVENING. -KT
&&
.AVIATION...
ISOLATED THUNDERSTORMS ACROSS THE MOUNTAINS WILL BECOME MORE
SCATTERED TO NUMEROUS THIS AFTERNOON. ALTHOUGH MAJORITY OF
THUNDERSTORMS SHOULD STAY TIED TO THE HIGHER TERRAIN...KCOS COULD
SEE TS IN THE VCNTY AFTER 21Z...AND HAVE ADDED THIS TO THE 18Z
TAFS. KALS WILL SEE THE BEST CHANCE OF TSRA AFFECTING THE TERMINAL
WITH POTENTIAL FOR ERRATIC GUSTY WINDS AND BRIEF VFR CIGS. LOCALLY
HEAVY RAINFALL WILL BE POSSIBLE WITH THUNDERSTORMS
TODAY...PARTICULARLY ACROSS THE MOUNTAIN AREAS. GUSTY SOUTH WINDS
WILL AFFECT ALL THREE TERMINALS THIS AFTERNOON WITH GUSTS IN THE
20-25 KT RANGE...THOUGH STRONGER GUSTS TO 35 KTS WILL BE POSSIBLE
NEAR -TSRA. THUNDERSTORMS WILL DIMINISH OVERNIGHT WITH ISOLATED
THUNDERSTORMS POSSIBLE THROUGH THE NIGHT ALONG THE CONTDVD. A WEAK
COLD FRONT WILL MOVE INTO THE SE PLAINS ON MONDAY BRINGING A WIND
SHIFT FROM THE NORTH...THEN NORTHEAST TO EAST AT KCOS DURING THE
AFTERNOON. THIS SHOULD INCREASE -TSRA CHANCES FOR FRI AFTERNOON
FOR THE KCOS TERMINAL.
&&
.PREV DISCUSSION... /ISSUED 444 AM MDT THU JUL 5 2012/
SHORT TERM...
(TODAY AND TONIGHT)
..BREEZY TODAY WITH MOST PRECIPITATION ALONG THE CONTDVD...
CURRENTLY...
IN THE CWA...A FEW LIGHT SHOWERS WERE NOTED OVER THE GREATER LA
JUNTA AREA AND ALONG THE CONTDVD. A LARGE AREA OF PRECIP WAS OVER NE
CO AND A CLUSTER OF SHOWERS WAS NOTED OVER SW CO. SFC MOISTURE
CONTINUES TO INCREASE OVER THE REGION AS DWPTS WERE IN THE 40S AND
50S AT ALL LOCATIONS EXCEPT AT THE HIGHER MTN LOCATIONS WHERE THEY
WERE IN THE 40S. IT WAS STILL MILD OVER THE PLAINS WITH 80S OBSERVED
AT 2 AM AT KLHX AND KLAA. TEMPS AT THE HIGHER ELEVATIONS OF THE
MTNS...ON THE OTHER HAND...WERE RATHER COOL WITH LOWER/MID 40S AT A
QUITE A FEW LOCATIONS.
TODAY...
SIMULATIONS SHOW MOST OF THE PRECIP TODAY WILL BE MAINLY OVER THE
CONTDVD AND HAVE DRAWN HIGHEST POPS THIS LOCATION. OVER THE PLAINS
IT WILL BE BREEZY TODAY IN RESPONSE TO AN INCREASING PRESSURE
GRADIENT ASSOCIATED WITH A SHORTWAVE MOVING NORTHEAST TO THE NORTH
OF THE AREA. WITH NO SIGNIFICANT FORCING ON THE PLAINS
TODAY...LITTLE IF ANY PRECIP WAS BEING INDICATED ON THE PLAINS...AND
HAVE KEPT MOST OF THE PLAINS DRY. THE MTNS ADJACENT TO THE
PLAINS...INCLUDING THE WALDO CANYON BURN AREA...WILL ONLY SEE ISOLD
SHOWERS TODAY...AND THEY WILL LIKELY FORM LATE IN THE DAY AND EARLY
EVENING.
TEMPS TODAY WILL CONTINUE TO BE HOT...ALTHOUGH THE BREEZY CONDITIONS
WILL HELP TEMPER THE HEAT A BIT. I HAVE PUEBLO REACHING 100
AGAIN...BUT THERE IS A HIGH PROBABILITY THIS WILL BE THE LAST DAY
THIS HAPPENS FOR AWHILE (SEE LONG TERM DISCUSSION BELOW).
ALTHOUGH IT WILL BE ON THE BREEZY SIDE TODAY...METEOROLOGICAL
CONDITIONS FOR EXTREME FIRE BEHAVIOR ARE NOT ANTICIPATED DUE TO THE
HIGH MINIMUM RH VALUES EXPECTED FOR THIS AFTERNOON (MIN RH VALUES
SHOULD REMAIN ABOVE 15% ALL REGIONS).
TONIGHT...
SHORT WAVE DISCUSSED ABOVE WILL MOVE PAST THE LONGITUDE OF THE
REGION...AND THIS WILL CAUSE THE BRISK SOUTHERLY FLOW OVER THE
REGION TO SHIFT TO A WESTERLY DIRECTION DURING THE LATE
EVENING/EARLY MORNING HOURS. ANY SHOWERS THIS EVENING WILL DISSIPATE
OVER NEARLY ALL OF THE AREA BY LATE EVENING. THE ONLY LOCATIONS
WHICH MAY SEE SOME LIGHT SHOWERS WILL BE ALONG THE CONTDVD. /34
LONG TERM...
(FRIDAY NIGHT THROUGH WEDNESDAY)
..LOCALLY HEAVY RAINFALL POSSIBLE INTO EARLY NEXT WEEK...
FRIDAY-FRIDAY NIGHT...WEAK SOUTH TO SOUTHWEST FLOW ALOFT PROGGED
ACROSS THE REGION WITH THE CENTER OF A LARGE UPPER LEVEL HIGH
PRESSURE SYSTEM OVER THE CENTRAL HIGH PLAINS SLOWLY RETROGRADES
ACROSS THE ROCKIES AS AN EMBEDDED SHORT WAVE TRANSLATES ACROSS ZONAL
FLOW ESTABLISHED ACROSS THE NORTHERN TIER AND UPPER GREAT LAKES.
MODELS IN DECENT AGREEMENT IN KEEPING BULK OF MONSOONAL MOISTURE
PLUME ACROSS WESTERN PORTIONS OF THE STATE FRIDAY NIGHT. MODELS ALSO
IN GOOD AGREEMENT OF PASSING NORTHERN TIER SYSTEM SENDING A COLD
FRONT INTO NORTHEASTERN COLORADO FRIDAY MORNING WHICH STALLS NEAR
THE PALMER DVD FRIDAY AFTERNOON. WITH STRONG SOLAR HEATING AND
MOISTURE IN PLACE...SHOULD SEE SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS DEVELOPING ACROSS THE HIGHER TERRAIN THROUGH THE EARLY
AFTERNOON. IN ADDITION...WITH WEAK EASTERLY FLOW AND LOW LEVEL
MOISTURE POOLING ALONG AND BEHIND COLD FRONT...COULD SEE STORMS
DEVELOPING ACROSS THE PIKES PEAK REGION AND PALMER DVD THROUGH THE
LATE AFTERNOON AND EVENING. STORMS WILL BE SLOW MOVING OWNING TO THE
POTENTIAL FOR LOCALLY HEAVY RAINFALL. CONVECTION TO HELP PUSH
BOUNDARY SOUTH ACROSS THE REST OF THE PLAINS FRIDAY NIGHT WITH
DEVELOPING WEAK UPSLOPE FLOW AND LOW LEVEL MOISTURE ALLOWING FOR
STRATUS TO DEVELOP ACROSS THE EASTERN PLAINS THROUGH THE
OVERNIGHT.
SATURDAY-MONDAY...UPPER HIGH CONTINUES TO BUILD BACK ACROSS THE
ROCKIES THROUGH THE WEEKEND WITH LIGHT AND VARIABLE FLOW ALOFT
PROGGED ACROSS THE AREA THROUGH EARLY NEXT WEEK. MONSOONAL MOISTURE
PLUME TO BE IN PLACE UNDERNEATH THE RIDGE...WITH SURFACE HIGH
PRESSURE BUILDING ACROSS THE NORTHERN AND CENTRAL HIGH PLAINS
KEEPING WEAK EASTERLY UPSLOPE FLOW AND LOW LEVEL MOISTURE IN PLACE
ACROSS EASTERN COLORADO...WILL SET THE STAGE FOR LOCALLY HEAVY
RAINFALL AREA WIDE. STORMS TO DEVELOP ACROSS THE HIGHER TERRAIN
THROUGH THE LATE MORNINGS AND AFTERNOONS...SPREADING OUT AND
DEVELOPING ACROSS THE ADJACENT PLAINS THROUGH THE FAR SE PLAINS
THROUGH THE LATE AFTERNOONS AND EVENINGS. WILL NEED TO CONTINUE
TO MONITOR THE POTENTIAL FOR HEAVY RAINFALL ALONG WITH FLASH
FLOODING...ESPECIALLY ON THE WALDO CANYON AND OTHER BURN SCARS
ACROSS THE AREA. WITH MORE CLOUDS AND COOLER UPSLOPE FLOW...SHOULD
SEE TEMPERATURES FALLING TO AT OR BELOW SEASONAL AVERAGES THROUGH
THE PERIOD.
TUESDAY-WEDNESDAY...WEAK NORTH TO NORTHEAST FLOW ALOFT PROGGED
ACROSS THE REGION WHICH UPPER HIGH BUILDING INTO THE DESERT
SOUTHWEST THROUGH THE GREAT BASIN...WITH MOISTURE PLUME BEING
PUSHING SOUTH AND WEST OF THE AREA. STILL WILL BE ENOUGH MOISTURE
FOR ISOLATED TO SCATTERED AFTERNOON AND EVENING THUNDERSTORMS THOUGH
WILL BECOME MORE HIGH BASED WITH DRIER AIR WORKING INTO THE AREA
FROM THE NORTH. THE MORE EASTERLY FLOW ALOFT WILL KEEP STORMS AWAY
FROM THE I-25 CORRIDOR AND THE EASTERN PLAINS...OWNING TO DRIER AND
WARMER CONDITIONS INTO THE MIDDLE OF NEXT WEEK. -MW
AVIATION...
VFR EXPECTED AT ALL TAF SITES TODAY (KCOS...KPUB AND KALS). THUNDER
SHOULD REMAIN MOSTLY OVER THE HIGHER TERRAIN TODAY AND I PLAN TO NOT
MENTION THUNDER AT KCOS OR KPUB DURING THE NEXT 24H. WILL HAVE VCTS
AT KALS THIS AFTERNOON. IT WILL BE BREEZY AT THE TAF SITES
TODAY...ESPECIALLY AT KCOS AND KPUB...WITH GUSTY SOUTHERLY WINDS
(~15G28KT).
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
31/81
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
657 PM EDT THU JUL 5 2012
.UPDATE...
QUICK UPDATE TO FINE TUNE POP AND WX GRIDS BASED ON CURRENT TRENDS
...ESP MCS OVER ERN TN. LAST SEVERAL HRRR RUNS HAVE BEEN IN GOOD
AGREEMENT ON BRINGING MCS DOWN INTO NRN COUNTIES AROUND 00-01Z AND
INTO ATL METRO AROUND 02-03Z. SHOULD WEAKEN AS IT MOVES SOUTH BUT
EXPECT SIGNIFICANT THREAT FOR DAMAGING WINDS THIS EVENING IN NORTH
GA. WILL UPDATE HWO AS WELL.
SNELSON
&&
.PREV DISCUSSION... /ISSUED 158 PM EDT THU JUL 5 2012/
SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
GEORGIA REMAINS UNDER THE EASTERN END OF THE CENTRAL U.S. RIDGE
THROUGH THE PERIOD. ALTHOUGH THE RIDGE IS FORECAST BY THE GFS/NAM
AND ECMWF TO BUILD EASTWARD SOME FRIDAY AND WILL CONTINUE TO BE
STRONG ENOUGH FOR ABOVE NORMAL TEMPERATURES...IT SHOULD NOT BE
STRONG ENOUGH TO SUPPRESS SCATTERED...MAINLY DIURNAL...CONVECTION.
PERSISTENT SURFACE TROUGH IN THE LEE OF THE APPALACHIANS WILL
CONTINUE TO PROVIDE SOME LOW LEVEL SUPPORT FOR THUNDERSTORM
DEVELOPMENT. ANY WEAK MID LEVEL CIRCULATIONS FROM MORE WIDESPREAD
CONVECTION ALONG THE NORTHERN PERIPHERY OF THE RIDGE THAT MAKE IT
AROUND THE EASTERN POINT OF THE RIDGE...LIKE THE PAIR MOVING THROUGH
THE EASTERN OHIO VALLEY AND CENTRAL APPALACHIANS THIS AFTERNOON...
MAY HELP TO FOCUS CONVECTIVE ACTIVITY AS WELL ACROSS NORTH GEORGIA
EACH AFTERNOON. STRONG SURFACE HEATING AND AMPLE LOW LEVEL MOISTURE
ARE IN PLACE AGAIN THIS AFTERNOON AND WILL BE PRESENT FRIDAY
AFTERNOON FOR MODERATE INSTABILITY. HOWEVER...COMBINED WITH WEAK
SHEAR AND A LACK OF A STRONG FOCUSING MECHANISM THIS SHOULD KEEP
SEVERE THUNDERSTORM THREAT ISOLATED.
WITH AFTERNOON HIGH TEMPERATURES EXPECTED TO REMAIN IN THE MID TO
UPPER 90S...AFTERNOON HEAT INDEX VALUES WILL REMAIN UNCOMFORTABLY
HIGH...BUT COMBINED WITH OVERNIGHT LOWS IN THE UPPER 60S TO LOWER
70S IN MOST AREAS WE ARE NOT EXPECTED TO REACH HEAT ADVISORY
CRITERIA THROUGH THE PERIOD.
20
LONG TERM /SATURDAY THROUGH THURSDAY/...
NO CHANGES TO CURRENT LONG TERM PLANNED. PREVIOUS LONG TERM
DISCUSSION FOLLOWS...
/ISSUED 414 AM EDT THU JUL 5 2012/
THE MODELS ARE IN GOOD AGREEMENT IN THE EXTENDED PERIODS. THE UPPER
LEVEL RIDGING SHIFTS WEST OVER THE CENTRAL PLAINS ALLOWING WEAK
IMPULSES TO CONTINUE TO IMPACT PORTIONS OF THE SOUTHEAST...
PROVIDING FOCUS FOR MAINLY DIURNALLY DRIVEN CONVECTION. MODELS
AGREE MAIN FOCUS TO BE ACROSS NORTH GEORGIA ON SATURDAY AND SUNDAY
AHEAD OF A BROAD LONGWAVE TROUGH WHICH SETS UP OVER THE EASTERN
U.S. BY MONDAY AFTERNOON. AT THE SFC...WEAK SURFACE BOUNDARY
REMAINS IN CLOSE PROXIMITY TO THE FORECAST AREA...EVENTUALLY
SAGGING SOUTH BY SUNDAY NIGHT...SPREADING THE FOCUS FOR
CONVECTION SOUTHWARD THROUGH THE END OF THE EXTENDED PERIODS.
MODELS CONTINUE TO SHOW GOOD MOISTURE ACROSS THE AREA...
PRECIPITABLE WATER REMAINS NEAR 2 INCHES...AND PLENTY OF
INSTABILITY...SURFACE CAPES GREATER THAN 1500 EACH AFTERNOON WITH
DIURNALLY DRIVEN CONVECTION POSSIBLE ACROSS ALL OF NORTH
AND CENTRAL GEORGIA. GUIDANCE TEMPERATURES NEAR OR JUST ABOVE
NORMAL THROUGH THE EXTENDED PERIODS. BELIEVE MONDAY THROUGH
WEDNESDAY AFTERNOON TEMPERATURES ARE ON THE COOL SIDE AS MODELS
MAY BE OVERDOING CLOUD COVER ASSOCIATED WITH THE SURFACE BOUNDARY.
ANTICIPATE LESS CLOUDS UNTIL HEATING KICKS IN EACH DAY AND HAVE
GONE WARMER THAN GUIDANCE LATTER PORTIONS OF THE FORECAST.
ATWELL/17
AVIATION...
18Z UPDATE...
VFR CONDITIONS ARE EXPECTED OUTSIDE OF CONVECTION THROUGH 08Z.
ISOLATED TO SCATTERED AREAS OF MVFR VISIBILITIES ARE EXPECTED
BETWEEN 08Z AND 14Z...BUT ONLY TAF SITES I EXPECT TO BE IMPACTED
WOULD BE KAHN AND POSSIBLY KMCN. ISOLATED TO SCATTERED CONVECTION
ALREADY DEVELOPING IN FAR NORTH GEORGIA. THIS TREND SHOULD CONTINUE
WITH ISOLATED TO SCATTERED CONVECTION SPREADING SOUTH THROUGH
02Z...TAPERING OFF QUICKLY AFTER 02Z. WINDS WILL REMAIN WESTERLY
BETWEEN 5 AND 10KT THROUGH 00Z...THEN DIMINISH TO 5 KT OR LESS.
//ATL CONFIDENCE...18Z UPDATE...
HIGH.
20
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 72 98 72 99 / 60 40 40 30
ATLANTA 75 97 75 96 / 50 40 40 30
BLAIRSVILLE 67 94 67 91 / 70 40 40 40
CARTERSVILLE 68 98 69 98 / 60 40 40 40
COLUMBUS 74 96 75 94 / 50 40 40 30
GAINESVILLE 73 97 73 98 / 60 40 40 40
MACON 74 96 74 96 / 50 40 40 30
ROME 69 98 69 98 / 60 40 40 40
PEACHTREE CITY 68 96 69 95 / 50 40 40 30
VIDALIA 76 96 75 96 / 50 40 40 30
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...SNELSON
LONG TERM....39
AVIATION...SNELSON
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
319 PM CDT THU JUL 5 2012
.SYNOPSIS...
12Z UA ANALYSIS HAD A LLJ RUNNING FROM WEST TEXAS INTO NORTHWEST
IOWA. AN 850MB BOUNDARY/FRONT RAN FROM THE ARROWHEAD OF MINNESOTA
INTO WESTERN NEBRASKA. MOISTURE WAS POOLING AHEAD OF THE BOUNDARY
WITH 850MB DEW POINTS IN THE MID AND UPPER TEENS FROM SOUTHERN
MINNESOTA INTO WISCONSIN. SATELLITE TRENDS THROUGH MID AFTERNOON
SHOW CLOUDS CONTINUE TO THIN FROM THE NOCTURNAL CONVECTION OVER
THE AREA WITH DIURNAL CU AND ISOLATED CONVECTION IN NORTHEAST
ILLINOIS.
18Z SFC ANALYSIS HAD WEAK LOWS NEAR KLSE AND KSUX. AN OUTFLOW
BOUNDARY CONNECTED THE TWO LOWS AND RAN ACROSS NORTHERN IOWA. THE
MAIN COLD FRONT RAN FROM WESTERN LAKE SUPERIOR TO KFSD AND THEN
INTO SOUTHERN SOUTH DAKOTA. DEW POINTS WERE IN THE 40S AND 50S
BEHIND THE FRONT WITH WIDESPREAD 60S AND SOME 70S AHEAD OF THE FRONT.
&&
.SHORT TERM...TONIGHT AND FRIDAY
THERE IS SOME MOISTURE ABOVE THE LFC SO THERE REALLY IS NO CAP.
THE LACK OF A TRIGGER HAS SO FAR PREVENTED ANY ELEVATED CONVECTION
FROM DEVELOPING. ELEVATED CONVECTION HAS DEVELOPED IN NORTHEAST
ILLINOIS IN RESPONSE TO WEAK FORCING PER THE RAP MODEL. DIURNAL CU
HAS DEVELOPED ALONG THE TRUE COLD FRONT AND VISIBLE/WATER VAPOR
IMAGERY INDICATES A WEAK VORT MAX OR MCV MOVING ACROSS SOUTHERN
MINNESOTA. THUS CONVECTION SHOULD DEVELOP IN THE NEXT FEW HOURS IN
MINNESOTA ALONG THE FRONT.
THE CONVECTION IN NORTHEAST ILLINOIS WILL NEED TO BE WATCHED. RAP
TRENDS SHOW THE WEAK FORCING GETTING CLOSE TO THE EASTERN CWFA
LATE THIS AFTERNOON. MCS...LIFT...AND WAA TOOLS ALL SUGGEST
ADDITIONAL CONVECTION DEVELOPING LATE THIS AFTERNOON IN NORTHEAST
ILLINOIS THAT MAY APPROACH THE FAR NORTHEAST/EAST PARTS OF THE
CWFA. IF NOTHING DEVELOPS BY 6 PM...THEN THE CWFA SHOULD BE DRY
THROUGH MIDNIGHT.
AFTER MIDNIGHT ANOTHER MCS SHOULD DEVELOP IN SOUTHERN MINNESOTA
AND GENERALLY MOVE EAST. THE GENESIS REGION SHOULD BE SOUTHWEST
MINNESOTA IN THE STRONGEST PART OF THE WEAK LLJ. OUTFLOWS FROM
THIS MCS MAY INITIATE NEW CONVECTION PRIOR TO SUNRISE JUST OUTSIDE
OF THE CWFA.
ASSUMING THE MINNESOTA MCS DEVELOPS AND MOVES EAST AS EXPECTED
THEN FRIDAY SHOULD SEE PLENTY OF DEBRIS CLOUDS THAT TAKE MOST OF
THE MORNING TO THIN AND DISSIPATE. THESE CLOUDS IN TURN SHOULD
HOLD DOWN TEMPERATURES JUST A LITTLE BUT MAX TEMPERATURES SHOULD
BE SIMILAR TO OR 1-2 DEGREES WARMER THAN TODAY.
THE HEAT HEADLINES WILL REMAIN WITH NO CHANGES. DEW POINTS SHOULD
AGAIN DROP TONIGHT AS EVAPOTRANSPIRATION FROM THE CORN BECOMES
INACTIVE. DEW POINTS WILL CLIMB AGAIN FRIDAY INTO THE UPPER 60S TO
POSSIBLY MID 70S AS THE CORN ACTIVELY EVAPOTRANSPIRATES. THE
RESULTANT HEAT INDEX READINGS SHOULD BE 105 TO 110. ..08..
.LONG TERM...FRIDAY NIGHT THROUGH NEXT THURSDAY
BREAK IN THE HEAT WITH MORE SEASONABLE TEMPS AND COMFORTABLE HUMIDITY
ARRIVING BY LATE IN THE WEEKEND. THE FRONT BRINGING THE RELIEF
UNFORTUNATELY DOESN/T FIGURE TO BRING MUCH IN WAY OF NEEDED RAINFALL
FOR AREA CORN CROPS IN CRITICAL POLLINATION STAGE. MOST OF THE
AREA IS NOW EXPERIENCING MODERATE DROUGHT CONDITIONS PER THE LATEST
U.S. DROUGHT MONITOR RELEASED THIS AM.
SURFACE COLD FRONT TO SAG THROUGH THE REGION SAT INTO SAT NGT. FRI NGT
WILL FEATURE CONTINUATION OF EXCESSIVE HEAT WARNING WITH VERY WARM
AND HUMID CONDITIONS WITH HEAT INDICES REMAINING ABOVE 75. NOT LIKELY
TO SEE SFC BASED PRE-FRONTAL CONVECTION SAT INTO SAT EVE DUE TO STRONG
CAPPING INVERSION... WEAK LOW LEVEL CONVERGENCE AND ABSENCE OF
PRONOUNCED SHORTWAVE AND MID LEVEL COOLING. THUS... ANY PCPN WOULD BE
POST-FRONTAL ROOTED WITH CONVERGENCE AXIS NEAR TO ABOVE 850 MILLIBARS
ALSO COINCIDENT WITH DEEPER MOISTURE FETCH WITH MONSOONAL CONNECTION
ROTATING AROUND THE PERIPHERY OF THE UPPER RIDGE /HEAT DOME/ TO OUR SOUTH.
WITH LACK OF CONVECTION PRE-FRONTAL THEN LESS DEBRIS CLOUDINESS THUS
INCREASING LIKELIHOOD OF NEEDING TO EXTEND HEAT WARNING THROUGH
SAT FOR A GOOD PORTION OF THE CWA FOR HIGHS ONCE AGAIN WELL INTO THE
90S TO AROUND 100F AND HEAT INDICES 100-110+. 850 MILLIBAR FRONT
OR WEAKENING CONVERGENCE AXIS PASSES SUN INTO SUN EVE TAKING MOISTURE
WITH IT. ASIDE FROM THE WEAK CONVERGENCE HARD PRESSED TO FIND COHERENT
FORCING OR TRIGGER TO GENERATE WIDESPREAD OR ORGANIZED RAIN. GIVEN
ALL OF THE ABOVE HAVE BACKED OFF ON POPS TO MAINLY SLIGHT CHC DURING THE
ENTIRE PERIOD SAT-SUN.
MON-THU... GENERAL PATTERN WILL FEATURE A BROAD TROUGH OVER THE
CENTRAL AND EASTERN CONUS... AND RIDGE OVER THE INTERMOUNTAIN
WEST. RESULTING NORTHWEST FLOW WILL KEEP TEMPS AROUND NORMAL WHICH
COUPLED WITH LOWER HUMIDITY TO MAKE FOR NICE AND COMFORTABLE STRETCH
OF WEATHER. PCPN CHCS ARE NOT ZERO AS WE COULD SEE A FEW SHORTWAVES
PASS IN THE FLOW... BUT WITH LIMITED MOISTURE AND TIMING/STRENGTH
SO DIFFICULT TO PIN DOWN THIS FAR OUT HAVE MAINTAINED A DRY FORECAST.
MCCLURE
&&
.AVIATION... /ISSUED 1234 PM CDT THU JUL 5 2012/
VFR WX WILL CONTINUE THROUGH 00Z/07 WITH DENSITY ALTITUDES AOA
3KFT 18Z/05-02Z/06 AND AGAIN AFT 16Z/06. THERE IS AN EXTREMELY LOW
CHANCE OF A TSRA OR VCTS AT KDBQ/KCID EITHER LATE THIS AFTERNOON
OR AFTER 03Z/06. HOWEVER...THIS POSSIBILITY WAS NOT INCLUDED IN
THE 18Z TAFS. ..08..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...EXCESSIVE HEAT WARNING UNTIL 7 AM CDT SATURDAY 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...EXCESSIVE HEAT WARNING UNTIL 7 AM CDT SATURDAY FOR BUREAU-
CARROLL-HANCOCK-HENDERSON-HENRY IL-JO DAVIESS-MCDONOUGH-
MERCER-PUTNAM-ROCK ISLAND-STEPHENSON-WARREN-WHITESIDE.
MO...EXCESSIVE HEAT WARNING UNTIL 7 AM CDT SATURDAY FOR CLARK-
SCOTLAND.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1234 PM CDT THU JUL 5 2012
.UPDATE...
RADAR/SATELLITE TRENDS SHOW THE CONVECTION ALONG THE IA/MN BORDER
IS SLOWLY DISSIPATING. DEBRIS CLOUDS FROM THIS CONVECTION HAS
TEMPERATURES PLUS/MINUS 1-2 DEGREES COMPARED 17Z YESTERDAY. THE
CLOUDS SHOULD CONTINUE TO SLOWLY THIN THROUGH THE AFTERNOON BUT
MAX TEMPERATURES TODAY MAY END UP BEING VERY SIMILAR TO YESTERDAY. AS
SUCH THE FCST MAX TEMPERATURES HAVE BEEN ADJUSTED DOWNWARD
SLIGHTLY.
THE RAP CONTINUES TO SHOW A WEAK SFC LOW MOVING FROM NEAR KFSD
ALONG THE MN/IA BORDER WHICH MAY MAINTAIN OR REGENERATE DIURNAL
CONVECTION THIS AFTERNOON ALONG THE FRONT/BOUNDARY. IF THIS DOES
OCCUR THEN THE BETTER CHANCES FOR CONVECTION SHOULD BE NORTH OF
THE CWFA. ..08..
&&
.AVIATION...
VFR WX WILL CONTINUE THROUGH 00Z/07 WITH DENSITY ALTITUDES AOA
3KFT 18Z/05-02Z/06 AND AGAIN AFT 16Z/06. THERE IS AN EXTREMELY LOW
CHANCE OF A TSRA OR VCTS AT KDBQ/KCID EITHER LATE THIS AFTERNOON
OR AFTER 03Z/06. HOWEVER...THIS POSSIBILITY WAS NOT INCLUDED IN
THE 18Z TAFS. ..08..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...EXCESSIVE HEAT WARNING UNTIL 7 AM CDT SATURDAY FOR BENTON-
BUCHANAN-CEDAR-CLINTON-DELAWARE-DES MOINES-DUBUQUE-HENRY IA-
IOWA-JACKSON-JEFFERSON-JOHNSON-JONES-KEOKUK-LEE-LINN-LOUISA-
MUSCATINE-SCOTT-VAN BUREN-WASHINGTON.
IL...EXCESSIVE HEAT WARNING UNTIL 7 AM CDT SATURDAY FOR BUREAU-
CARROLL-HANCOCK-HENDERSON-HENRY IL-JO DAVIESS-MCDONOUGH-
MERCER-PUTNAM-ROCK ISLAND-STEPHENSON-WARREN-WHITESIDE.
MO...EXCESSIVE HEAT WARNING UNTIL 7 AM CDT SATURDAY FOR CLARK-
SCOTLAND.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1143 AM MDT THU JUL 5 2012
.UPDATE...
ISSUED AT 1025 AM MDT THU JUL 5 2012
INCREASED DEW POINTS A FEW DEGREES FOR THE AFTERNOON BASED ON
LATEST TRENDS. THIS RAISED THE HEAT INDEX TO NEAR 105 DEGREES FOR
A FEW HOURS THIS AFTERNOON FOR THE HILL CITY...NORTON AND MCCOOK AREAS.
WILL HOLD OFF ISSUING A HEAT ADVISORY SINCE THIS WILL BE A
MARGINAL EVENT AT BEST.
UPDATE ISSUED AT 748 AM MDT THU JUL 5 2012
ONLY CHANGE WAS TO UPGRADE THE REMAINING FIRE WEATHER WATCH TO A
RED FLAG WARNING. WILL LIKELY BE A LOW END EVENT...BUT WITH THE
EXTREMELY DRY FUELS WILL ERROR ON THE SIDE OF CAUTION.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 432 AM MDT THU JUL 5 2012
FORECAST CONCERNS THIS PERIOD WILL BE HIGH TEMPERATURES/FIRE WEATHER
CONCERNS. SATELLITE SHOWING SAME PATTERN WITH UPPER TROUGHS ALONG
EACH COAST AND BROAD RIDGE OVER MOST OF THE COUNTRY. TROUGHS HAVE
SHOWN A LITTLE TREND TOWARD DEEPENING. SUBTROPICAL MOISTURE
CONTINUES TO FEED IN AROUND THE UPPER HIGH. COLD FRONT MOVED INTO THE
NORTHERN PORTIONS AND HELPED BRING SOME PRECIPITATION TO THAT AREA .
MODELS INITIALIZED FINE AT JET LEVEL. AT MID LEVELS THE NAM...SREF...
UKMET AND CANADIAN WERE DOING THE BEST. THE NAM...SREF...CANADIAN...
AND SREF WERE DOING VERY WELL ON THE SURFACE WIND/PRESSURE FIELD.
IN GENERAL MODELS WERE DOING WELL ON LOW LEVEL THERMAL FIELD WITH
THE NAM...UKMET...AND CANADIAN DOING A LITTLE BETTER AND THE ECMWF
THE WORST.
TODAY/TONIGHT...HAVE HAD LINGERING CONVECTION BUT IS ON THE
DECREASING TREND. IT LOOKS LIKE IT WILL BE DONE BY 12Z SO LEFT ANY
MORNING MENTION OUT. OTHERWISE MAIN LIFT AND MOISTURE WILL BE
PUSHED WEST OF THE AREA WITH MUCH WARMER 700 TO 500 MB TEMPERATURES
EXPECTED. THIS WILL CAP THE AIR MASS. SO REMOVED MENTION OF
THUNDERSTORMS FROM THIS AFTERNOON AND TONIGHT. UNLESS MESOSCALE
INFLUENCES FROM OVERNIGHT THUNDERSTORMS CAUSES PROBLEMS...MAXES
SHOULD BE SIMILAR TO YESTERDAYS.
FRIDAY...COLD FRONT MOVES BACK INTO THE NORTHWEST PORTION OF THE
AREA WITH INSTABILITY AND MID LEVEL LIFT GRAZING THE WEST. THIS WAS
VERY SIMILAR TO CURRENT FORECAST AND DID NOT CHANGE. EXCEPT MAYBE
FOR THE FAR NORTHWEST...MAX TEMPERATURES SHOULD BE SIMILAR TO
THURSDAYS.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 432 AM MDT THU JUL 5 2012
FORECAST CONCERNS TURN TO HOW COOL TO MAKE TEMPERATURES THIS PERIOD
FOLLOWED BY INCREASING CHANCES FOR PRECIPITATION BEGINNING SATURDAY.
FRIDAY NIGHT...KEPT THUNDERSTORMS IN THE FAR WESTERN PORTION PER
DISCUSSION ABOVE.
SATURDAY/SATURDAY NIGHT...THIS IS WHERE THE FORECAST GETS
COMPLICATED. MODELS DIFFER ON HOW FAR THEY WANT TO MOVE A FRONT INTO
THE AREA. SO THIS RESULTS IN BIG DIFFERENCES IN THE TEMPERATURE AND
PRECIPITATION FORECASTS. IT COULD GO EITHER WAY BUT THERE WAS
SLIGHTLY MORE SUPPORT TO GO COOLER AND ADJUSTED MAXES SLIGHTLY DOWN.
MODELS ARE ALSO ALL OVER THE PLACE IN HOW HANDLE THE MID/UPPER
LEVELS. VERY WEAK LIFT IN PLACE BUT PLENTY OF MOISTURE AND
INSTABILITY...I GUESS IT IS SUMMER. MODELS HAVE A VARIETY OF QPF
SOLUTIONS. AM THINKING THE FAR WEST HAS THE BEST SHOT FOR
PRECIPITATION BUT COULD HAPPEN ABOUT ANYPLACE. SO KEPT THE CURRENT
FORECAST IN FOR THE NIGHT.
SUNDAY THROUGH WEDNESDAY...DETERMINISTIC AND ENSEMBLES HAVE COME
INTO VERY GOOD AGREEMENT ON UPCOMING PATTERN CHANGE. HIGHLY
AMPLIFIED UPPER RIDGE DEVELOPS TO THE WEST WHICH WILL BRING COOLER
AND UNSETTLED CONDITIONS TO THE AREA. FOR THE MOST PART KEPT THE
INHERITED CRH_INIT GRIDS. HOWEVER...BASED ON 850 MB TEMPERATURES
CONVERGING ON EXPECTED VALUES...DID LOWER THE HIGH TEMPERATURES ON
SUNDAY AND MONDAY. HOWEVER THOSE MAY BE TOO WARM BASED ON EASTERLY
UPSLOPE FLOW IN A POST FRONTAL REGIME. THESE DAYS AND REMAINDER OF
THE FORECAST WILL NEED TO BE LOOKED AT FOR COOLING THEM OFF.
WITH SHORTWAVE TROUGHS COMING THROUGH IN NORTH TO NORTHWEST FLOW
ALOFT IN A POST FRONTAL UPSLOPE SITUATION...LOOK TO GIVE AREA A
GOOD CHANCE OF PRECIPITATION WITH SUNDAY NIGHT THROUGH MONDAY NIGHT
LOOKING WET.
THANKS TO ALL THAT COLLABORATED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1139 AM MDT THU JUL 5 2012
VFR CONDITIONS ARE FORECAST FOR THE 18Z TAFS. SOUTHERLY WINDS WILL
INCREASE THROUGH MID AFTERNOON BEFORE BEGINNING TO DECLINE. FRIDAY
THERE MAY BE SOME ISOLATED THUNDERSTORMS NEAR KGLD AS A SURFACE
TROUGH MOVES IN FROM THE NORTHWEST. AT THIS TIME WILL NOT PLACE A
MENTION OF THUNDERSTORMS IN THE TAF DUE TO THEIR ISOLATED NATURE.
&&
.FIRE WEATHER...
ISSUED AT 432 AM MDT THU JUL 5 2012
FOR TODAY...MESOSCALE INFLUENCES FROM CURRENT OVERNIGHT CONVECTION
MAKING THE FORECAST MORE COMPLICATED THAN EXPECTED. HOW LONG THE COLD
POOL BEHIND OUTFLOW BOUNDARIES KEEPS WINDS FROM PICKING UP PLUS
RELATIVE HUMIDITIES WILL BE KEPT HIGHER THAN ANTICIPATED. HRRR IS THE
ONLY MODEL CAPTURING CURRENT OUTFLOW BOUNDARIES. BETWEEN 15Z AND 18Z
IT SHIFTS THE WINDS BACK TO THE SOUTH AND INCREASES THEM. ALSO
TEMPERATURES LOOK TO RISE NICELY AFTER THIS.
THE FURTHER WEST COUNTIES LOOK TO HAVE THE BEST COMBINATION OF
RELATIVE HUMIDITIES...WHICH ARE CLOSE TO THRESHOLDS...AND THE
STRONGEST WINDS. ALSO SOME FIRES OCCURRED AND ARE ONGOING IN A FEW
COUNTIES IN THIS AREA. SO UPGRADED THAT AREA TO A RED FLAG WARNING.
MARGINAL CONDITIONS ARE IN THE COUNTIES JUST TO THE EAST OF THIS
AREA. KEPT THE WATCH THERE FOR NOW AND WILL LET THE DAY SHIFT LOOK AT
THE TRENDS. THE NORTHEAST MOST COUNTIES LOOK TO NOT HAVE STRONG
ENOUGH WINDS SO REMOVED THEM FROM THE WATCH.
FOR FRIDAY...POSITION OF A BOUNDARY WILL AGAIN PLAY A KEY ROLE.
RELATIVE HUMIDITIES ARE MARGINAL AT THIS TIME. AS THE FRONT MOVES IN
THE STRONGEST WINDS WILL BE PUSHED SOUTH AND EAST. TOO MUCH
UNCERTAINTY PLUS HAVE A COMPLICATED FIRE WEATHER HIGHLIGHT OUT
ALREADY SO WILL NOT ISSUE ANYTHING NOW AND MENTION IN THE HWO. THE
SOUTHEAST HALF OF THE AREA HAS THE BEST CHANCE TO REACH CRITERIA.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...RED FLAG WARNING UNTIL 7 PM MDT /8 PM CDT/ THIS EVENING FOR
KSZ001-002-013>015-027>029-041-042.
CO...RED FLAG WARNING UNTIL 7 PM MDT THIS EVENING FOR COZ252>254.
NE...RED FLAG WARNING UNTIL 7 PM MDT THIS EVENING FOR NEZ079.
&&
$$
UPDATE...JTL
SHORT TERM...BULLER
LONG TERM...BULLER
AVIATION...JTL
FIRE WEATHER...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1029 AM MDT THU JUL 5 2012
.UPDATE...
ISSUED AT 1025 AM MDT THU JUL 5 2012
INCREASED DEW POINTS A FEW DEGREES FOR THE AFTERNOON BASED ON
LATEST TRENDS. THIS RAISED THE HEAT INDEX TO NEAR 105 DEGREES FOR
A FEW HOURS THIS AFTERNOON FOR THE HILL CITY...NORTON AND MCCOOK AREAS.
WILL HOLD OFF ISSUING A HEAT ADVISORY SINCE THIS WILL BE A
MARGINAL EVENT AT BEST.
UPDATE ISSUED AT 748 AM MDT THU JUL 5 2012
ONLY CHANGE WAS TO UPGRADE THE REMAINING FIRE WEATHER WATCH TO A
RED FLAG WARNING. WILL LIKELY BE A LOW END EVENT...BUT WITH THE
EXTREMELY DRY FUELS WILL ERROR ON THE SIDE OF CAUTION.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 432 AM MDT THU JUL 5 2012
FORECAST CONCERNS THIS PERIOD WILL BE HIGH TEMPERATURES/FIRE WEATHER
CONCERNS. SATELLITE SHOWING SAME PATTERN WITH UPPER TROUGHS ALONG
EACH COAST AND BROAD RIDGE OVER MOST OF THE COUNTRY. TROUGHS HAVE
SHOWN A LITTLE TREND TOWARD DEEPENING. SUBTROPICAL MOISTURE
CONTINUES TO FEED IN AROUND THE UPPER HIGH. COLD FRONT MOVED INTO THE
NORTHERN PORTIONS AND HELPED BRING SOME PRECIPITATION TO THAT AREA .
MODELS INITIALIZED FINE AT JET LEVEL. AT MID LEVELS THE NAM...SREF...
UKMET AND CANADIAN WERE DOING THE BEST. THE NAM...SREF...CANADIAN...
AND SREF WERE DOING VERY WELL ON THE SURFACE WIND/PRESSURE FIELD.
IN GENERAL MODELS WERE DOING WELL ON LOW LEVEL THERMAL FIELD WITH
THE NAM...UKMET...AND CANADIAN DOING A LITTLE BETTER AND THE ECMWF
THE WORST.
TODAY/TONIGHT...HAVE HAD LINGERING CONVECTION BUT IS ON THE
DECREASING TREND. IT LOOKS LIKE IT WILL BE DONE BY 12Z SO LEFT ANY
MORNING MENTION OUT. OTHERWISE MAIN LIFT AND MOISTURE WILL BE
PUSHED WEST OF THE AREA WITH MUCH WARMER 700 TO 500 MB TEMPERATURES
EXPECTED. THIS WILL CAP THE AIR MASS. SO REMOVED MENTION OF
THUNDERSTORMS FROM THIS AFTERNOON AND TONIGHT. UNLESS MESOSCALE
INFLUENCES FROM OVERNIGHT THUNDERSTORMS CAUSES PROBLEMS...MAXES
SHOULD BE SIMILAR TO YESTERDAYS.
FRIDAY...COLD FRONT MOVES BACK INTO THE NORTHWEST PORTION OF THE
AREA WITH INSTABILITY AND MID LEVEL LIFT GRAZING THE WEST. THIS WAS
VERY SIMILAR TO CURRENT FORECAST AND DID NOT CHANGE. EXCEPT MAYBE
FOR THE FAR NORTHWEST...MAX TEMPERATURES SHOULD BE SIMILAR TO
THURSDAYS.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 432 AM MDT THU JUL 5 2012
FORECAST CONCERNS TURN TO HOW COOL TO MAKE TEMPERATURES THIS PERIOD
FOLLOWED BY INCREASING CHANCES FOR PRECIPITATION BEGINNING SATURDAY.
FRIDAY NIGHT...KEPT THUNDERSTORMS IN THE FAR WESTERN PORTION PER
DISCUSSION ABOVE.
SATURDAY/SATURDAY NIGHT...THIS IS WHERE THE FORECAST GETS
COMPLICATED. MODELS DIFFER ON HOW FAR THEY WANT TO MOVE A FRONT INTO
THE AREA. SO THIS RESULTS IN BIG DIFFERENCES IN THE TEMPERATURE AND
PRECIPITATION FORECASTS. IT COULD GO EITHER WAY BUT THERE WAS
SLIGHTLY MORE SUPPORT TO GO COOLER AND ADJUSTED MAXES SLIGHTLY DOWN.
MODELS ARE ALSO ALL OVER THE PLACE IN HOW HANDLE THE MID/UPPER
LEVELS. VERY WEAK LIFT IN PLACE BUT PLENTY OF MOISTURE AND
INSTABILITY...I GUESS IT IS SUMMER. MODELS HAVE A VARIETY OF QPF
SOLUTIONS. AM THINKING THE FAR WEST HAS THE BEST SHOT FOR
PRECIPITATION BUT COULD HAPPEN ABOUT ANYPLACE. SO KEPT THE CURRENT
FORECAST IN FOR THE NIGHT.
SUNDAY THROUGH WEDNESDAY...DETERMINISTIC AND ENSEMBLES HAVE COME
INTO VERY GOOD AGREEMENT ON UPCOMING PATTERN CHANGE. HIGHLY
AMPLIFIED UPPER RIDGE DEVELOPS TO THE WEST WHICH WILL BRING COOLER
AND UNSETTLED CONDITIONS TO THE AREA. FOR THE MOST PART KEPT THE
INHERITED CRH_INIT GRIDS. HOWEVER...BASED ON 850 MB TEMPERATURES
CONVERGING ON EXPECTED VALUES...DID LOWER THE HIGH TEMPERATURES ON
SUNDAY AND MONDAY. HOWEVER THOSE MAY BE TOO WARM BASED ON EASTERLY
UPSLOPE FLOW IN A POST FRONTAL REGIME. THESE DAYS AND REMAINDER OF
THE FORECAST WILL NEED TO BE LOOKED AT FOR COOLING THEM OFF.
WITH SHORTWAVE TROUGHS COMING THROUGH IN NORTH TO NORTHWEST FLOW
ALOFT IN A POST FRONTAL UPSLOPE SITUATION...LOOK TO GIVE AREA A
GOOD CHANCE OF PRECIPITATION WITH SUNDAY NIGHT THROUGH MONDAY NIGHT
LOOKING WET.
THANKS TO ALL THAT COLLABORATED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 529 AM MDT THU JUL 5 2012
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. LIGHT AND VARIABLE
WINDS WILL SHIFT TO THE SOUTH...INCREASE...AND BECOME GUSTY UNTIL
EARLY THIS EVENING.
&&
.FIRE WEATHER...
ISSUED AT 432 AM MDT THU JUL 5 2012
FOR TODAY...MESOSCALE INFLUENCES FROM CURRENT OVERNIGHT CONVECTION
MAKING THE FORECAST MORE COMPLICATED THAN EXPECTED. HOW LONG THE COLD
POOL BEHIND OUTFLOW BOUNDARIES KEEPS WINDS FROM PICKING UP PLUS
RELATIVE HUMIDITIES WILL BE KEPT HIGHER THAN ANTICIPATED. HRRR IS THE
ONLY MODEL CAPTURING CURRENT OUTFLOW BOUNDARIES. BETWEEN 15Z AND 18Z
IT SHIFTS THE WINDS BACK TO THE SOUTH AND INCREASES THEM. ALSO
TEMPERATURES LOOK TO RISE NICELY AFTER THIS.
THE FURTHER WEST COUNTIES LOOK TO HAVE THE BEST COMBINATION OF
RELATIVE HUMIDITIES...WHICH ARE CLOSE TO THRESHOLDS...AND THE
STRONGEST WINDS. ALSO SOME FIRES OCCURRED AND ARE ONGOING IN A FEW
COUNTIES IN THIS AREA. SO UPGRADED THAT AREA TO A RED FLAG WARNING.
MARGINAL CONDITIONS ARE IN THE COUNTIES JUST TO THE EAST OF THIS
AREA. KEPT THE WATCH THERE FOR NOW AND WILL LET THE DAY SHIFT LOOK AT
THE TRENDS. THE NORTHEAST MOST COUNTIES LOOK TO NOT HAVE STRONG
ENOUGH WINDS SO REMOVED THEM FROM THE WATCH.
FOR FRIDAY...POSITION OF A BOUNDARY WILL AGAIN PLAY A KEY ROLE.
RELATIVE HUMIDITIES ARE MARGINAL AT THIS TIME. AS THE FRONT MOVES IN
THE STRONGEST WINDS WILL BE PUSHED SOUTH AND EAST. TOO MUCH
UNCERTAINTY PLUS HAVE A COMPLICATED FIRE WEATHER HIGHLIGHT OUT
ALREADY SO WILL NOT ISSUE ANYTHING NOW AND MENTION IN THE HWO. THE
SOUTHEAST HALF OF THE AREA HAS THE BEST CHANCE TO REACH CRITERIA.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...RED FLAG WARNING UNTIL 7 PM MDT /8 PM CDT/ THIS EVENING FOR
KSZ001-002-013>015-027>029-041-042.
CO...RED FLAG WARNING UNTIL 7 PM MDT THIS EVENING FOR COZ252>254.
NE...RED FLAG WARNING UNTIL 7 PM MDT THIS EVENING FOR NEZ079.
&&
$$
UPDATE...JTL
SHORT TERM...BULLER
LONG TERM...BULLER
AVIATION...BULLER
FIRE WEATHER...BULLER
AREA FORECAST DISCUSSION
NWS JACKSON KY
126 PM EDT THU JUL 5 2012
.UPDATE...
ISSUED AT 111 PM EDT THU JUL 5 2012
ACTIVITY HAS QUICKLY PICKED UP AHEAD AND ALONG THE LEADING EDGE OF
THE COLD POOL DROPPING IN FROM THE NORTH. LOTS OF ACTIVITY DEVELOPING
AND SHOULD PERSIST THROUGH THE REMAINDER OF THE AFTERNOON AS IT DROPS
SOUTHWARD ACROSS THE AREA. LOTS OF INSTABILITY TO TAP INTO WITH
SBCAPE AROUND 5000 J/KG. THUS...LOOK FOR DAMAGING WINDS AS THE MAIN
THREAT WITH LARGE HAIL A SECONDARY THREAT. HRRR HAS MUCH OF THE
ACTIVITY EXITING TO OUR SOUTH AROUND 6 PM THIS EVENING WHICH SEEMS
REASONABLE AT THE CURRENT SPEED OF THE OUTFLOW BOUNDARY.
UPDATE ISSUED AT 1157 AM EDT THU JUL 5 2012
OUTFLOW BOUNDARY CONTINUES TO DROP SOUTH AND IS NOW BEGINNING TO PUSH
INTO FAR NORTHERN KENTUCKY. THE BOUNDARY HAS TURNED QUITE ACTIVE TO
THE EAST CLOSE TO CHARLESTON...BUT HAS NOT YET TURNED ACTIVE FURTHER
TO THE WEST. HOWEVER...WITH 5000J/KG OF SBCAPE DEVELOPING...I EXPECT
TO SEE SOME EXPANSION TO THE WEST ALONG THIS LINE AS WE HEAD THROUGH
THE AFTERNOON. GIVEN THE THREAT...SPC HAS ISSUED A SEVERE
THUNDERSTORM WATCH THROUGH 7 PM TONIGHT FOR AREA MAINLY TO THE EAST
OF I-75. PEOPLE WITH OUTDOOR PLANS SHOULD STAY TUNED TO THE WEATHER
THIS AFTERNOON AND BE PREPARED TO TAKE ACTION. HAVE ALSO INCREASED
POPS TO LIKELY FOR THE AREA THIS AFTERNOON AS MOST AREAS SHOULD SEE
SOME PRECIPITATION.
UPDATE ISSUED AT 924 AM EDT THU JUL 5 2012
MCS DEVELOPED OVER SOUTHERN MICHIGAN EARLY THIS MORNING AND HAS
WEAKENED AS IT TRACKED SOUTH INTO NORTHERN AND CENTRAL OHIO.
HOWEVER...THIS SYSTEM HAS DEVELOPED A COLD POOL AND MCV WHICH WILL
CONTINUE TRACKING SOUTH INTO THIS AFTERNOON AND EVENING. AFTER THE
INVERSION BREAKS THIS MORNING...SBCAPE WILL SURGE TO AT LEAST 4000
J/KG AN POTENTIALLY HIGHER. WITH THE MCV DROPPING SOUTH DURING THE
PEAK HEATING...WE SHOULD SEE PRETTY DECENT SHOWER AND THUNDERSTORM
DEVELOPMENT. THIS IS CERTAINLY SUPPORTED BY THE HRRR AND RUC.
THUS...HAVE INCREASED POPS TO AROUND 40 ACROSS EASTERN KENTUCKY AND
MAY NEED TO GO EVEN HIGHER...BUT WILL WAIT TO SEE HOW THE MCV
DEVELOPS UPSTREAM BEFORE JUMPING ON BOARD COMPLETELY.
REGARDLESS...MUCH LIKE THE PAST FEW DAYS...ANY OUTFLOW BOUNDARIES
WILL EASILY BE CAPABLE OF 40 MPH WINDS AND NEAR THE STRONGER
THUNDERSTORMS WINDS COULD REACH 60 MPH. THUS...THE MAIN THREAT WILL
BE DAMAGING WINDS. A FEW MORE ORGANIZED STORMS WILL BE CAPABLE OF
HAIL...BUT I EXPECT THE MAIN THREAT TO BE DAMAGING WINDS. FORECAST
HAS BEEN UPDATED TO REFLECT ALL OF THESE CHANGES. DEPENDING ON HOW
FAST CONVECTION DEVELOPS TODAY...THAT COULD PUT OUR HIGHS A TAD LOWER
THAN CURRENTLY FORECAST. BUT FOR NOW WILL STICK CLOSE TO OUR PREVIOUS
FORECAST AND WAIT TO SEE HOW THINGS DEVELOP.
UPDATE ISSUED AT 640 AM EDT THU JUL 5 2012
MAINLY FRESHENED UP THE GRIDS TO ACCOUNT FOR THE LATEST OBSERVATIONAL
TRENDS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 352 AM EDT THU JUL 5 2012
HEAT WILL CONTINUE TO BE THE MAIN STORY AS THE CENTRAL CONUS UPPER
LEVEL RIDGE EXPANDS MORE INTO THE OHIO AND TENNESSEE VALLEYS THROUGH
THE SHORT TERM. RECORD HIGHS WILL GET SQUASHED TODAY THROUGH SATURDAY
WITH READINGS RANGING IN THE 95 TO 100 DEGREE RANGE FOR MOST
LOCATIONS. WE HAD A FEW SPOTS EVEN IN THE EAST CREEP TO OVER A 100
DEGREE HEAT INDICES YESTERDAY...AND SINCE TEMPERATURES WILL GENERALLY
BE A DEGREE OR SO WARMER TODAY AND AGAIN ON FRIDAY...HAVE GONE AHEAD
AND EXPANDED THE HEAT ADVISORY FOR THE REST OF THE AREA. HAVE ALSO
EXTENDED THE ADVISORY THROUGH SATURDAY...AS READINGS LOOK TO BE
SIMILAR TO FRIDAY...WITH HEAT INDICES GENERALLY PEAKING IN THE 100
TO 105 DEGREE RANGE...WITH SLIGHTLY HIGHER VALUES TOWARDS THE
BLUEGRASS AND WEST OF I-75.
THE CONVECTIVE TRENDS CONTINUE TO BE CHALLENGING THROUGH THE SHORT
TERM...HOWEVER GIVEN THE MORE LIMITED COVERAGE THAT OCCURRED
YESTERDAY AND THE LACK OF DEEPER MOISTURE AS WELL QUESTIONABLE
TRIGGERS THROUGH FRIDAY...ITS HARD TO REALLY ADVERTISE MORE THAN
ISOLATED POPS...SO HAVE STUCK WITH THIS IDEA FROM THE INHERITED
FORECAST. THE NAM HAS BEEN PLAYING UP A POTENTIAL MCS FOR
TONIGHT...HOWEVER GIVEN THE POOR CONVECTIVE INITIALIZATION...THERE IS
NOT MUCH CONFIDENCE IN THIS SCENARIO AT THIS TIME.
FOR TEMPERATURES...PRETTY MUCH ADDED A DEGREE OR SO FROM THE HIGHS
THAT WERE ACHIEVED ON WEDNESDAY FOR TODAY...AND THEN ANOTHER DEGREE
FOR FRIDAY. LOWS TONIGHT WILL GENERALLY BE BETWEEN 70 AND 75...WITH A
FEW SHELTERED VALLEYS DIPPING INTO THE UPPER 60S.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 352 AM EDT THU JUL 5 2012
FOR THE EXTENDED THE MODELS ARE IN FAIRLY GOOD AGREEMENT THAT THE
RENEWED UPPER RIDGE OVER THE MID SECTION OF THE NATION WILL BE
SHUNTED WESTWARD AND WEAKENED BY TROUGHING TO THE NORTHEAST STARTING
DURING THE LATTER PART OF THE WEEKEND. HEIGHTS WILL FALL THROUGH
EAST KENTUCKY BEGINNING ON SUNDAY AND CONTINUE INTO TUESDAY WHEN THE
NORTHEAST TROUGH AXIS PASSES THROUGH THE REGION ACCOMPANIED BY AT
LEAST SOME SHORTWAVE ENERGY. FOR WEDNESDAY...BOTH THE GFS AND LATEST
ECMWF HAVE PARKED A MINIMA OF HEIGHTS OVER EAST KENTUCKY IN RESPONSE
TO RIDGING BUILDING OVER THE WEST. THIS APPEARS TO BE THE CLEAR
PATTERN CHANGE THAT WE HAVE BEEN WAITING AND HOPING FOR AND WILL
BREAK THE HEAT WAVE. SEVERAL RUNS IN A ROW HAVE CONFIRMED THE
BREAKDOWN AND RETREAT OF THE RIDGE SO CONFIDENCE IS PRETTY GOOD THAT
WE CAN TALK SERIOUSLY ABOUT TEMPERATURES RETURNING TO SEASONAL
NORMALS BEFORE TOO LONG INTO THE START OF NEXT WEEK.
SENSIBLE WEATHER WILL FEATURE ANOTHER VERY WARM DAY OR TWO OVER THE
WEEKEND WITH UPPER RIDGING LIKELY KEEPING ANY CONVECTION AT BAY ON
SATURDAY WITH A BIT HIGHER PCPN POTENTIAL ANTICIPATED FOR SUNDAY AS
HEIGHTS FALL ALOFT AND A WAVY SFC BOUNDARY CREEPS CLOSER FROM THE
NORTH. IT IS THIS BOUNDARY THAT HAS BEEN IN MOST DISPUTE AMONG THE
MODELS THESE PAST SEVERAL RUNS WITH THE GFS AND GEM PUSHING ITO
SOUTH INTO...AN IN SOME CASES THROUGH...KENTUCKY AS EARLY AS SUNDAY
EVENING. THE NEW...AND PREFERRED...ECMWF WILL SAG THIS FRONT INTO
OUR PART OF THE STATE ON MONDAY PROPER AND HOLD IT THERE AS A PRIME
WEATHER FACTOR INTO TUESDAY. LATER ON FOR WEDNESDAY...IT FORMS A
WAVE ON THE BOUNDARY OVER EAST KENTUCKY THAT...SHOULD THIS OCCUR...
WILL CERTAINLY HEARTEN OUR HOPES FOR DROUGHT MITIGATING RAINS. HAVE
NOT BOUGHT TOTALLY INTO THIS SCENARIO AS OF YET...BUT DID GUIDE THE
GRIDS TOWARDS IT IN CONJUNCTION WITH THE CR POPULATION SCRIPT
STARTING POINT.
BY THE START OF THE NEW WEEK WE SHOULD BE LOOKING AT TEMPERATURES
CLOSER TO NORMAL AND A RETURN OF DECENT CHANCES OF CONVECTION AND
MUCH NEEDED RAINFALL.
THE GRID LOAD CAME IN AS A PRETTY GOOD AMALGAM OF THE ECMWF AND GFS
SO ONLY HAD TO TWEAK THE POPS A TAD EACH DAY TO TILT THE SCALE MORE
TOWARD THE OVERSEAS MODEL AND ALSO ENHANCE THE DIURNAL NATURE OF THE
POPS. IN ADDITION...MADE SOME FINE TUNE ADJUSTMENTS TO THE LOW
TEMPERATURES EACH NIGHT TO ACCOUNT FOR SOME TERRAN DETAILS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 125 PM EDT THU JUL 5 2012
NUMEROUS SHOWERS AND THUNDERSTORMS WILL DROP SOUTHWARD ACROSS EASTERN
KENTUCKY THIS AFTERNOON. THIS STORMS WILL PROVIDE SOME VERY GUSTY
WINDS AT TIMES. THE STRONGER STORMS COULD GUSTS UP TO 50 KNOTS. THE
THUNDERSTORM THREAT MAY DIMINISH TOWARDS 00Z...BUT COULD LINGER A BIT
LONGER. BY MIDNIGHT...THINGS WILL TURN MUCH QUIETER AND SHOULD
CONTINUE THROUGH TOMORROW MORNING. MORE ISOLATED STORMS WILL BE
POSSIBLE FRIDAY AFTERNOON.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY UNTIL 8 PM EDT SATURDAY FOR KYZ044-050>052-058>060-
068-069-079-080-083>088-104-106>120.
&&
$$
UPDATE...KAS
SHORT TERM...GEOGERIAN
LONG TERM....GREIF
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
111 PM EDT THU JUL 5 2012
.UPDATE...
ISSUED AT 111 PM EDT THU JUL 5 2012
ACTIVITY HAS QUICKLY PICKED UP AHEAD AND ALONG THE LEADING EDGE OF
THE COLD POOL DROPPING IN FROM THE NORTH. LOTS OF ACTIVITY DEVELOPING
AND SHOULD PERSIST THROUGH THE REMAINDER OF THE AFTERNOON AS IT DROPS
SOUTHWARD ACROSS THE AREA. LOTS OF INSTABILITY TO TAP INTO WITH
SBCAPE AROUND 5000 J/KG. THUS...LOOK FOR DAMAGING WINDS AS THE MAIN
THREAT WITH LARGE HAIL A SECONDARY THREAT. HRRR HAS MUCH OF THE
ACTIVITY EXITING TO OUR SOUTH AROUND 6 PM THIS EVENING WHICH SEEMS
REASONABLE AT THE CURRENT SPEED OF THE OUTFLOW BOUNDARY.
UPDATE ISSUED AT 1157 AM EDT THU JUL 5 2012
OUTFLOW BOUNDARY CONTINUES TO DROP SOUTH AND IS NOW BEGINNING TO PUSH
INTO FAR NORTHERN KENTUCKY. THE BOUNDARY HAS TURNED QUITE ACTIVE TO
THE EAST CLOSE TO CHARLESTON...BUT HAS NOT YET TURNED ACTIVE FURTHER
TO THE WEST. HOWEVER...WITH 5000J/KG OF SBCAPE DEVELOPING...I EXPECT
TO SEE SOME EXPANSION TO THE WEST ALONG THIS LINE AS WE HEAD THROUGH
THE AFTERNOON. GIVEN THE THREAT...SPC HAS ISSUED A SEVERE
THUNDERSTORM WATCH THROUGH 7 PM TONIGHT FOR AREA MAINLY TO THE EAST
OF I-75. PEOPLE WITH OUTDOOR PLANS SHOULD STAY TUNED TO THE WEATHER
THIS AFTERNOON AND BE PREPARED TO TAKE ACTION. HAVE ALSO INCREASED
POPS TO LIKELY FOR THE AREA THIS AFTERNOON AS MOST AREAS SHOULD SEE
SOME PRECIPITATION.
UPDATE ISSUED AT 924 AM EDT THU JUL 5 2012
MCS DEVELOPED OVER SOUTHERN MICHIGAN EARLY THIS MORNING AND HAS
WEAKENED AS IT TRACKED SOUTH INTO NORTHERN AND CENTRAL OHIO.
HOWEVER...THIS SYSTEM HAS DEVELOPED A COLD POOL AND MCV WHICH WILL
CONTINUE TRACKING SOUTH INTO THIS AFTERNOON AND EVENING. AFTER THE
INVERSION BREAKS THIS MORNING...SBCAPE WILL SURGE TO AT LEAST 4000
J/KG AN POTENTIALLY HIGHER. WITH THE MCV DROPPING SOUTH DURING THE
PEAK HEATING...WE SHOULD SEE PRETTY DECENT SHOWER AND THUNDERSTORM
DEVELOPMENT. THIS IS CERTAINLY SUPPORTED BY THE HRRR AND RUC.
THUS...HAVE INCREASED POPS TO AROUND 40 ACROSS EASTERN KENTUCKY AND
MAY NEED TO GO EVEN HIGHER...BUT WILL WAIT TO SEE HOW THE MCV
DEVELOPS UPSTREAM BEFORE JUMPING ON BOARD COMPLETELY.
REGARDLESS...MUCH LIKE THE PAST FEW DAYS...ANY OUTFLOW BOUNDARIES
WILL EASILY BE CAPABLE OF 40 MPH WINDS AND NEAR THE STRONGER
THUNDERSTORMS WINDS COULD REACH 60 MPH. THUS...THE MAIN THREAT WILL
BE DAMAGING WINDS. A FEW MORE ORGANIZED STORMS WILL BE CAPABLE OF
HAIL...BUT I EXPECT THE MAIN THREAT TO BE DAMAGING WINDS. FORECAST
HAS BEEN UPDATED TO REFLECT ALL OF THESE CHANGES. DEPENDING ON HOW
FAST CONVECTION DEVELOPS TODAY...THAT COULD PUT OUR HIGHS A TAD LOWER
THAN CURRENTLY FORECAST. BUT FOR NOW WILL STICK CLOSE TO OUR PREVIOUS
FORECAST AND WAIT TO SEE HOW THINGS DEVELOP.
UPDATE ISSUED AT 640 AM EDT THU JUL 5 2012
MAINLY FRESHENED UP THE GRIDS TO ACCOUNT FOR THE LATEST OBSERVATIONAL
TRENDS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 352 AM EDT THU JUL 5 2012
HEAT WILL CONTINUE TO BE THE MAIN STORY AS THE CENTRAL CONUS UPPER
LEVEL RIDGE EXPANDS MORE INTO THE OHIO AND TENNESSEE VALLEYS THROUGH
THE SHORT TERM. RECORD HIGHS WILL GET SQUASHED TODAY THROUGH SATURDAY
WITH READINGS RANGING IN THE 95 TO 100 DEGREE RANGE FOR MOST
LOCATIONS. WE HAD A FEW SPOTS EVEN IN THE EAST CREEP TO OVER A 100
DEGREE HEAT INDICES YESTERDAY...AND SINCE TEMPERATURES WILL GENERALLY
BE A DEGREE OR SO WARMER TODAY AND AGAIN ON FRIDAY...HAVE GONE AHEAD
AND EXPANDED THE HEAT ADVISORY FOR THE REST OF THE AREA. HAVE ALSO
EXTENDED THE ADVISORY THROUGH SATURDAY...AS READINGS LOOK TO BE
SIMILAR TO FRIDAY...WITH HEAT INDICES GENERALLY PEAKING IN THE 100
TO 105 DEGREE RANGE...WITH SLIGHTLY HIGHER VALUES TOWARDS THE
BLUEGRASS AND WEST OF I-75.
THE CONVECTIVE TRENDS CONTINUE TO BE CHALLENGING THROUGH THE SHORT
TERM...HOWEVER GIVEN THE MORE LIMITED COVERAGE THAT OCCURRED
YESTERDAY AND THE LACK OF DEEPER MOISTURE AS WELL QUESTIONABLE
TRIGGERS THROUGH FRIDAY...ITS HARD TO REALLY ADVERTISE MORE THAN
ISOLATED POPS...SO HAVE STUCK WITH THIS IDEA FROM THE INHERITED
FORECAST. THE NAM HAS BEEN PLAYING UP A POTENTIAL MCS FOR
TONIGHT...HOWEVER GIVEN THE POOR CONVECTIVE INITIALIZATION...THERE IS
NOT MUCH CONFIDENCE IN THIS SCENARIO AT THIS TIME.
FOR TEMPERATURES...PRETTY MUCH ADDED A DEGREE OR SO FROM THE HIGHS
THAT WERE ACHIEVED ON WEDNESDAY FOR TODAY...AND THEN ANOTHER DEGREE
FOR FRIDAY. LOWS TONIGHT WILL GENERALLY BE BETWEEN 70 AND 75...WITH A
FEW SHELTERED VALLEYS DIPPING INTO THE UPPER 60S.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 352 AM EDT THU JUL 5 2012
FOR THE EXTENDED THE MODELS ARE IN FAIRLY GOOD AGREEMENT THAT THE
RENEWED UPPER RIDGE OVER THE MID SECTION OF THE NATION WILL BE
SHUNTED WESTWARD AND WEAKENED BY TROUGHING TO THE NORTHEAST STARTING
DURING THE LATTER PART OF THE WEEKEND. HEIGHTS WILL FALL THROUGH
EAST KENTUCKY BEGINNING ON SUNDAY AND CONTINUE INTO TUESDAY WHEN THE
NORTHEAST TROUGH AXIS PASSES THROUGH THE REGION ACCOMPANIED BY AT
LEAST SOME SHORTWAVE ENERGY. FOR WEDNESDAY...BOTH THE GFS AND LATEST
ECMWF HAVE PARKED A MINIMA OF HEIGHTS OVER EAST KENTUCKY IN RESPONSE
TO RIDGING BUILDING OVER THE WEST. THIS APPEARS TO BE THE CLEAR
PATTERN CHANGE THAT WE HAVE BEEN WAITING AND HOPING FOR AND WILL
BREAK THE HEAT WAVE. SEVERAL RUNS IN A ROW HAVE CONFIRMED THE
BREAKDOWN AND RETREAT OF THE RIDGE SO CONFIDENCE IS PRETTY GOOD THAT
WE CAN TALK SERIOUSLY ABOUT TEMPERATURES RETURNING TO SEASONAL
NORMALS BEFORE TOO LONG INTO THE START OF NEXT WEEK.
SENSIBLE WEATHER WILL FEATURE ANOTHER VERY WARM DAY OR TWO OVER THE
WEEKEND WITH UPPER RIDGING LIKELY KEEPING ANY CONVECTION AT BAY ON
SATURDAY WITH A BIT HIGHER PCPN POTENTIAL ANTICIPATED FOR SUNDAY AS
HEIGHTS FALL ALOFT AND A WAVY SFC BOUNDARY CREEPS CLOSER FROM THE
NORTH. IT IS THIS BOUNDARY THAT HAS BEEN IN MOST DISPUTE AMONG THE
MODELS THESE PAST SEVERAL RUNS WITH THE GFS AND GEM PUSHING ITO
SOUTH INTO...AN IN SOME CASES THROUGH...KENTUCKY AS EARLY AS SUNDAY
EVENING. THE NEW...AND PREFERRED...ECMWF WILL SAG THIS FRONT INTO
OUR PART OF THE STATE ON MONDAY PROPER AND HOLD IT THERE AS A PRIME
WEATHER FACTOR INTO TUESDAY. LATER ON FOR WEDNESDAY...IT FORMS A
WAVE ON THE BOUNDARY OVER EAST KENTUCKY THAT...SHOULD THIS OCCUR...
WILL CERTAINLY HEARTEN OUR HOPES FOR DROUGHT MITIGATING RAINS. HAVE
NOT BOUGHT TOTALLY INTO THIS SCENARIO AS OF YET...BUT DID GUIDE THE
GRIDS TOWARDS IT IN CONJUNCTION WITH THE CR POPULATION SCRIPT
STARTING POINT.
BY THE START OF THE NEW WEEK WE SHOULD BE LOOKING AT TEMPERATURES
CLOSER TO NORMAL AND A RETURN OF DECENT CHANCES OF CONVECTION AND
MUCH NEEDED RAINFALL.
THE GRID LOAD CAME IN AS A PRETTY GOOD AMALGAM OF THE ECMWF AND GFS
SO ONLY HAD TO TWEAK THE POPS A TAD EACH DAY TO TILT THE SCALE MORE
TOWARD THE OVERSEAS MODEL AND ALSO ENHANCE THE DIURNAL NATURE OF THE
POPS. IN ADDITION...MADE SOME FINE TUNE ADJUSTMENTS TO THE LOW
TEMPERATURES EACH NIGHT TO ACCOUNT FOR SOME TERRAN DETAILS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 640 AM EDT THU JUL 5 2012
EXPECT VFR CONDITIONS TO REIGN ACROSS THE AREA THE MAJORITY OF THE
TIME. ISOLATED THUNDERSTORMS WILL AGAIN BE POSSIBLE THIS
AFTERNOON...HOWEVER WITH THE LIMITED AREAL COVERAGE...WILL CONTINUE
TO LEAVE OUT THE MENTION IN THE TAFS. WINDS WILL BE LIGHT AND
VARIABLE THROUGH THE MID-MORNING...BEFORE ENGAGING OUT OF THE
NORTHWEST BETWEEN 5 AND 8 KTS DURING THE DAY...AND THEN DIMINISHING
TOWARDS DUSK.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY UNTIL 8 PM EDT SATURDAY FOR KYZ044-050>052-058>060-
068-069-079-080-083>088-104-106>120.
&&
$$
UPDATE...KAS
SHORT TERM...GEOGERIAN
LONG TERM....GREIF
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS CARIBOU ME
101 PM EDT THU JUL 5 2012
.SYNOPSIS...
AN UPPER LOW WILL CONTINUE TO MOVE EAST THROUGH THE MARITIMES TODAY.
HIGH PRESSURE WILL BRIEFLY BUILD ACROSS THE REGION LATER TODAY
INTO FRIDAY. ANOTHER COLD FRONT WILL APPROACH FROM THE WEST FRIDAY
NIGHT AND CROSS THE REGION SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
100 PM UPDATE...BIGGEST CHANGE WITH THIS UPDATE WAS TO ADD
ISOLATED THUNDERSTORMS BACK INTO THE FORECAST FOR ALL AREAS. WE`RE
SEEING MORE BREAKS IN THE CLOUD COVER THAN PREVIOUSLY ANTICIPATED,
WHICH HAVE ALLOWED SB CAPES TO REACH 500 J/KG OR MORE IN SCATTERED
LOCATIONS THROUGHOUT THE STATE. SHOWERS HAVE STARTED POPPING UP ON
RADAR OVER THE NORTH WOODS AND THESE SHOULD BECOME MORE NUMEROUS
AS WE GO THROUGH THE AFTERNOON. ALSO AJUSTED MAX TEMPS FOR TODAY
UP A BIT OWING TO THE INCREASED CHANCES FOR SUNSHINE. OTHERWISE,
NO OTHER CHANGES WERE NEEDED.
PREVIOUS DISCUSSION...
CHALLENGE IS HOW MUCH RAINFALL AND TEMPERATURES.
THE LATEST RADAR TRENDS SHOW SHOWERS AND ISOLD TSTMS OVER THE
EASTERN 1/2 OF THE CWA. THE BULK OF THE ACTIVITY IS E OF HOULTON
AND ACROSS THE INTERIOR DOWNEAST AND COASTAL REGIONS. THE LATEST
HRRR AND RUC LINED UP WELL THROUGH 12Z ALTHOUGH A BIT OVERDONE AS
FAR AS AREAL COVERAGE. MANUAL ADJUSTMENTS WERE MADE TO THE POPS TO
FIT BETTER W/THE RADAR AND SATL IMAGERY. THIS MEANS HIGHER PRECIP
CHANCES(60%) IN THE AFOREMENTIONED AREAS THIS MORNING. THE CLOSED
LOW IS SHOWN TO MIGRATE ACROSS THE GULF OF MAINE INTO THE
MARITIMES THIS EVENING. AS IT DOES SO, THE INVERTED TROF FROM THE
SFC LOW WILL SLIDE E. AFTER 12Z, DECIDED ON THE GFS AND ECMWF TO
POPS AS THEY APPEAR TO HAVE A GOOD HANDLE ON THE SYNOPTIC
SITUATION AND AREAL PLACEMENT OF QPF . THEREFORE, THE DECISION WAS
TO GO W/40-50% POPS LATER THIS MORNING INTO THE AFTERNOON FOR
SHOWERS. SOUNDINGS FROM THE GFS NOT OVERLY UNSTABLE W/SBCAPE OF
400-500 JOULES. THIS WILL ALSO BE DEPENDENT ON TEMPERATURES THIS
AFTERNOON. SATL IR IMAGERY DOES SHOW SOME PARTIAL CLEARING THIS
MORNING WHICH WILL AID IN HEATING. LAPSE RATE ARE MEAGER AT BEST
(5.5-6C/KM). SOME COOLING ALOFT IS NOTED. DECIDED TO CARRY ISOLD
TSTMS TO ACCOUNT FOR THIS AWAY FROM THE COAST AND MAINLY ALONG THE
EASTERN 1/2 OF THE CWA ALONG THE CONVERGENCE ZONE. LIGHT FLOW
ALOFT AND HIGH PWS(1.5") AND FZL LVLS OF 12.5 FT WILL LEAD TO
HEAVY RAINFALL IN ANY TSTMS. A BLEND OF THE GFS/ECMWF AND HPC WAS
USED FOR THE QPF W/MANUAL ADJUSTMENTS.
ACTIVITY WINDS DOWN TONIGHT AS THE LOW PULLS E AND LLVL
CONVERGENCE WEAKENS. PARTIAL CLEARING IS EXPECTED LATER TONIGHT
AND THIS COUPLED W/A WET SFC WILL ALLOW FOR SOME FOG FORMATION.
DECIDED TO ADD FOG FOR ALL AREAS. HYDROLAPSE RATES FROM THE MDL
SOUNDINGS SUPPORT FOG POTENTIAL. DAYCREW WILL NEED TO ASSESS THIS
FURTHER TODAY. RAISED DAYCREW/S MINS UP A CATEGORY USING THE LAMP
AND NAM12 TEMPERATURES.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
WINDS WILL TURN SOUTHWEST ON FRIDAY ALLOWING FOR WARMER TEMPERATURES
ACROSS THE FA. A SHORT WAVE MOVING ACROSS FROM THE WEST WILL BRING
THE CHANCE OF LATE DAY SHOWERS AND TSTMS TO MAINLY NORTHERN PORTIONS
OF THE FA. SB CAPES LOOK RATHER MODEST AS DO 0-6 KM SHEAR VALUES SO
SEVERE POTENTIAL NOT LOOKING ALL THAT HIGH. SHOWERS AND TSTMS WILL
LIKELY PERSIST INTO FRIDAY EVENING AS THE SHORT WAVE AND ASSOCIATED
COLD FRONT CROSSES THE REGION. A SECONDARY COLD FRONT COLD FRONT
WILL CROSS THE REGION SATURDAY WITH ANOTHER CHANCE FOR SHOWERS AND
TSTMS. HIGHS ON SATURDAY WILL RANGE FROM THE LOW TO MID 80S NORTH
AND MID TO UPPER 80S DOWNEAST.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AN UPPER LOW WILL REMAIN ACROSS EASTERN CANADA SATURDAY NIGHT INTO
EARLY NEXT WEEK AS SURFACE HIGH PRESSURE BUILD EAST. WEATHER
CONDITIONS DURING THE LONG TERM SHOULD BE MAINLY DRY BUT WITH WEAK
DISTURBANCES MOVING THROUGH COULDN`T RULE OUT AN ISOLATED SHOWER OR
TSTM FROM TIME TO TIME. TEMPERATURES THROUGH THE PERIOD WILL BE NEAR
NORMAL FOR THIS TIME OF YEAR.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
NEAR TERM: IFR/MVFR CONDITIONS THROUGH MID MORNING AND THEN
CONDITIONS LOOK LIKE THEY WILL IMPROVE TO VFR LATER THIS AFTERNOON
OR EVENING. A RETURN TO MVFR AND POSSIBLY IFR LATER TONIGHT W/FOG
DEVELOPING.
SHORT TERM: SCT TSTMS ARE EXPECTED MAINLY NRN AREAS FRIDAY AND THE
REGION WIDE ON SATURDAY. CONDITIONS SHOULD BE MAINLY VFR THROUGH
THE PERIOD BUT COULD DECREASE TO MVFR IN ANY HEAVIER TSTMS FRIDAY
AND SATURDAY.
&&
.MARINE...
NEAR TERM: NO HEADLINES THIS TERM. WINDS WILL BE GENERALLY LIGHT
FROM THE NNE AT 10 KTS OR LESS. SWELLS WILL BE COMMON THIS TERM
W/PERIODS OF 8-9 SECONDS. STAYED W/DAYCREW ASSESSMENT OF 2-3 FOOT
WAVES.
SHORT TERM: WINDS/SEAS SHOULD BE BELOW SCA LEVELS THROUGH THE PERIOD.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...HASTINGS/HEWITT
SHORT TERM...DUDA
LONG TERM...DUDA
AVIATION...HASTINGS/HEWITT
MARINE...HASTINGS/HEWITT/DUDA
AREA FORECAST DISCUSSION...UPDATED
NWS TWIN CITIES/CHANHASSEN MN
349 PM CDT THU JUL 5 2012
.DISCUSSION... (UPDATED)
AFTER FURTHER REVIEW...DECIDED TO HOLD ON TO THE EXCESSIVE HEAT
WARNING THROUGH 7 PM ON FRIDAY FROM REDWOOD FALLS THROUGH
MINNEAPOLIS AND ST. PAUL AS WELL AS NEW RICHMOND AND CHIPPEWA
FALLS WISCONSIN. THIS IS BASICALLY ONE ROW OF COUNTIES ADDED ON TO
THE NORTH SIDE THE EXCESSIVE HEAT WARNING FROM 10 PM TONIGHT
THROUGH 7 PM FRIDAY.
THE COOL FRONT HAS PUSHED TO THE IA/MN BORDER EARLY THIS
AFTERNOON AND STRETCHES EASTWARD ACROSS CENTRAL WI. DEW POINTS
HAVE LOWERED SIGNIFICANTLY BEHIND THE FRONT IN CENTRAL MN WITH
KAXN AND KLXL SOME 25 DEGREES LOWER THEN YESTERDAY AT THIS TIME.
UNFORTUNATELY... MIDDLE TO UPPER 70S DEW POINTS REMAIN IN PLACE
ACROSS FAR SOUTHERN MN AND IT WILL TAKE UNTIL SATURDAY BEFORE
THESE ARE FLUSHED OUT.
IN THE MEAN TIME...THE FORECAST AHEAD HAS SEVERAL CONCERNS. ONE
IS THE THREAT OF SEVERE WEATHER TONIGHT AND FRIDAY WHILE ANOTHER
REVOLVES AROUND THE HEAT INDICES ACROSS THE REGION ON FRIDAY.
OVERALL...THE DETERMINISTIC GUIDANCE IS IN GOOD AGREEMENT WITH THE
PATTERN AHEAD. THE BOUNDARY TO THE SOUTH WILL LIFT SLOW NORTH
TONIGHT...STRETCHING FROM THE SOUTH METRO TO WEST CENTRAL MN BY
DAYBREAK FRIDAY. THERE WILL BE SOME THUNDERSTORMS DEVELOP ALONG
THE FRONT LATER THIS AFTERNOON AND EVENING AND ISOLATED SEVERE
STORMS CAN/T BE RULED OUT. THERE WILL ALSO BE A SHORT WAVE MOVING
ACROSS SOUTH DAKOTA DURING THE NIGHT. ANOTHER ROUND OF THUNDERSTORMS
MAY BE ON OUR WESTERN BORDER BY DAYBREAK AT THE NOSE OF THE LOW
LEVEL JET. THIS IS WELL SUPPORTED BY THE DIFFERENTIAL TEMPERATURE
ADVECTION SCHEME.
IF THIS IS THE CASE...THE STORMS SHOULD DRIVE ON EAST ACROSS
CENTRAL MN FRIDAY MORNING ON THE NOSE OF THE LOW LEVEL JET. THIS
WOULD LEAD TO MORE CLOUD COVER AND PERHAPS HIGHS NOT REACHING TOO
FAR INTO THE 90S ACROSS THE TWIN CITIES AND AREAS ON NORTH. ON THE
OTHERHAND...IT/S POSSIBLE THAT THE STORMS WILL NOT BE THERE AND
THE BOUNDARY WILL SLIP A LITTLE TO THE NORTH DURING THE MORNING
AND EARLY AFTERNOON HOURS. THIS WOULD LEAD TO THE POTENTIAL FOR
UPPER 90S OCCURRING ACROSS THE METRO ALONG WITH DANGEROUS HEAT
INDICES A LITTLE FURTHER NORTH. AS A RESULT...HAVE ADDED ONE MORE
ROW OF COUNTIES TO THE EXCESSIVE HEAT WARNING THAT IS IN EFFECT
THROUGH 7 PM ON FRIDAY. HIGHS IN THE UPPER 90S ARE FORECAST FOR
SOUTH CENTRAL MN THROUGH ABOUT THE KEAU/AUGUSTA AREA AND THE
EXCESSIVE HEAT WARNING WILL CONTINUE FOR THESE AREAS THROUGH
FRIDAY AS WELL.
IF NO STORMS ARE ONGOING FRIDAY MORNING...THE THREAT FOR SEVERE
WEATHER SHOULD INCREASE ALONG THE BOUNDARY FRIDAY AFTERNOON AND
EVENING. THE SHEAR VALUES ARE QUITE RESPECTABLE ALONG WITH PLENTY
OF CAPE AND DCAPE. DAMAGING WINDS WOULD CERTAINLY BE THE PRIMARY
FACTOR AS WE HAVE SEEN TO OUR NORTH RECENTLY. IN ADDITION...THERE
SHOULD BE A RATHER EXTENSIVE AREA OF SHOWERS PASS ACROSS NORTHERN
MN ON FRIDAY AS STRONG MID LEVEL FRONTOGENESIS DEVELOPS ALONG WITH
A RATHER STRONG SIGNAL SEEN IN THE DIFFERENTIAL DIVERGENCE.
THE BOUNDARY WILL THEN SETTLE SOUTH FRIDAY NIGHT AND SATURDAY WITH
PRECIPITATION CHANCES SLOWLY DIMINISHING FROM NORTHWEST TO
SOUTHEAST BY LATE IN THE DAY ON SATURDAY. DRY WEATHER IS INDICATED
FOR SATURDAY NIGHT THROUGH THURSDAY OF NEXT WEEK AS THE UPPER
RIDGE SLIPS WEST AND NORTHWEST FLOW DEVELOPS OVER OUR AREA. HIGHS
WILL BE MUCH CLOSER TO NORMAL DURING THIS PERIOD WITH LOWER TO
MIDDLE 80S FORECAST.
&&
.AVIATION... /18Z TAF ISSUANCE/
MAIN AVIATION CONCERN IS LEFTOVER BOUNDARY THAT HAS MOVED AS FAR
SOUTH AS KMKT EARLY THIS AFTN. THIS BOUNDARY WILL BE THE FOCUS OF
TSRA DURING THE AFTN/EVENING AS THE BOUNDARY STALLS NEAR THE MN/IA
BORDER...AND MOVES BACK NORTHWARD TONIGHT. ALL OTHER MPX TAF SITES
WILL LIKELY BE SHRA/TSRA FREE UNTIL THE BOUNDARY MOVES NORTHWARD
THIS EVENING.
BASED ON THE LATEST HRRR AND HOW UNSTABLE THE ATMOSPHERE REMAINS
ACROSS FAR SOUTHERN MN...HAVE DECIDED TO ADD VCSH AT RWF AFT 20Z.
WITH THE LATER HRRR FORECASTING SHRA/TSRA NEAR RWF BY
20-22Z...THIS TAF MAY NEED TO BE UPDATED WITH TSRA/VCTS AND CBS.
WILL SEE HOW CONVECTION DEVELOPS THIS AFTN BEFORE CHG ANYTHING. AS
FOR AXN/STC...AS THE BOUNDARY MOVES NORTHWARD...AND A SUBTLE WAVE
MOVES ACROSS THE NORTHERN PLAINS...SHRA/TSRA SHOULD BEGIN TO
DEVELOP IN THE DAKOTAS...AND SPREAD E/NE ACROSS WESTERN/CENTRAL MN
AFT MIDNIGHT. HAVE INTRODUCE VCSH...AND PROB30 AFT 12Z FOR BOTH
STC/AXN. LATER SHIFTS CAN UPDATE HOW LOW CIGS/VSBYS GET BASED ON
RADAR TRENDS. RNH/EAU WILL LIKELY BE SHRA/TSRA FREE UNTIL AFT
18Z/06. WNDS WILL REMAIN FROM THE NORTH...OR BECOME N/NNE THIS
AFTN WITH SOME GUSTS...ESPECIALLY EARLY AT STC/RWF/AXN. WNDS WILL
SHIFT TO THE NE/ENE OVERNIGHT...THEN E/SE AT RWF/RNH/EAU DURING
THE DAY.
MSP...KEPT TAF CLR OF SHRA/TSRA UNTIL AFT 9Z WHICH THE POTENTIAL
OF ELEVATED CONVECTION DEVELOPS AS THE BOUNDARY MOVES NORTHWARD.
BEST POTENTIAL OF SHRA/TSRA WILL COME AFT 00Z/07. WNDS WILL
GENERALLY BE FROM THE N/NNE EARLY THIS AFTN...THEN SLOWLY BECOMING
ENE/E OVERNIGHT...THE SE/SW BY FRIDAY AFTN AS THE MAIN SFC WARM
FRONT MOVES BACK NORTH OF THE TERMINAL SITE. WILL INTRODUCE VCSH
AFT 9Z DUE TO SOME UNCERTAINTIES OF THE ELEVATED CONVECTION...BUT
CIGS/VSBYS SHOULD REMAIN VFR.
.FRIDAY EVENING...VFR/MVFR. CHC SHWRS/TSTMS. SHIFTING WINDS...BECOMING NE
5-10 KT.
.SATURDAY...VFR/MVFR. CHC SHWRS/TSTMS. WINDS NE 5-10 KT.
.SUNDAY...VFR. WINDS NE BECOMING NW AROUND 5 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...EXCESSIVE HEAT WARNING UNTIL 7 PM CDT FRIDAY FOR BLUE EARTH-
BROWN-CARVER-DAKOTA-FARIBAULT-FREEBORN-GOODHUE-HENNEPIN-LE
SUEUR-MARTIN-MCLEOD-NICOLLET-RAMSEY-REDWOOD-RENVILLE-RICE-
SCOTT-SIBLEY-STEELE-WASECA-WASHINGTON-WATONWAN.
EXCESSIVE HEAT WARNING UNTIL 10 PM CDT THIS EVENING FOR ANOKA-
CHISAGO-ISANTI-MEEKER-SHERBURNE-WRIGHT.
WI...EXCESSIVE HEAT WARNING UNTIL 7 PM CDT FRIDAY FOR CHIPPEWA-DUNN-
EAU CLAIRE-PEPIN-PIERCE-ST. CROIX.
EXCESSIVE HEAT WARNING UNTIL 10 PM CDT THIS EVENING FOR BARRON-
POLK-RUSK.
&&
$$
RAH/JLT
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
309 PM CDT THU JUL 5 2012
.DISCUSSION...
THE COOL FRONT HAS PUSHED TO THE IA/MN BORDER EARLY THIS
AFTERNOON AND STRETCHES EASTWARD ACROSS CENTRAL WI. DEW POINTS
HAVE LOWERED SIGNIFICANTLY BEHIND THE FRONT IN CENTRAL MN WITH
KAXN AND KLXL SOME 25 DEGREES LOWER THEN YESTERDAY AT THIS TIME.
UNFORTUNATELY... MIDDLE TO UPPER 70S DEW POINTS REMAIN IN PLACE
ACROSS FAR SOUTHERN MN AND IT WILL TAKE UNTIL SATURDAY BEFORE
THESE ARE FLUSHED OUT.
IN THE MEAN TIME...THE FORECAST AHEAD HAS SEVERAL CONCERNS. ONE
IS THE THREAT OF SEVERE WEATHER TONIGHT AND FRIDAY WHILE ANOTHER
REVOLVES AROUND THE HEAT INDICES ACROSS THE REGION ON FRIDAY.
OVERALL...THE DETERMINISTIC GUIDANCE IS IN GOOD AGREEMENT WITH THE
PATTERN AHEAD. THE BOUNDARY TO THE SOUTH WILL LIFT SLOW NORTH
TONIGHT...STRETCHING FROM THE SOUTH METRO TO WEST CENTRAL MN BY
DAYBREAK FRIDAY. THERE WILL BE SOME THUNDERSTORMS DEVELOP ALONG
THE FRONT LATER THIS AFTERNOON AND EVENING AND ISOLATED SEVERE
STORMS CAN/T BE RULED OUT. THERE WILL ALSO BE A SHORT WAVE MOVING
ACROSS SOUTH DAKOTA DURING THE NIGHT. ANOTHER ROUND OF THUNDERSTORMS
MAY BE ON OUR WESTERN BORDER BY DAYBREAK AT THE NOSE OF THE LOW
LEVEL JET. THIS IS WELL SUPPORTED BY THE DIFFERENTIAL TEMPERATURE
ADVECTION SCHEME.
IF THIS IS THE CASE...THE STORMS SHOULD DRIVE ON EAST ACROSS
CENTRAL MN FRIDAY MORNING ON THE NOSE OF THE LOW LEVEL JET. THIS
WOULD LEAD TO MORE CLOUD COVER AND PERHAPS HIGHS NOT REACHING TOO
FAR INTO THE 90S ACROSS THE TWIN CITIES AND AREAS ON NORTH. ON THE
OTHERHAND...IT/S POSSIBLE THAT THE STORMS WILL NOT BE THERE AND
THE BOUNDARY WILL SLIP A LITTLE TO THE NORTH DURING THE MORNING
AND EARLY AFTERNOON HOURS. THIS WOULD LEAD TO THE POTENTIAL FOR
UPPER 90S OCCURRING ACROSS THE METRO ALONG WITH DANGEROUS HEAT
INDICES A LITTLE FURTHER NORTH. HIGHS IN THE UPPER 90S ARE FORECAST
FOR SOUTH CENTRAL MN THROUGH ABOUT THE KEAU/AUGUSTA AREA AND THE
EXCESSIVE HEAT WARNING WILL CONTINUE FOR THESE AREAS THROUGH FRIDAY.
THIS ALSO INCLUDES THE SOUTH METRO. IN THE END...INCREASED THE
HIGH FOR KMSP TO 94 ON FRIDAY.
IF NO STORMS ARE ONGOING FRIDAY MORNING...THE THREAT FOR SEVERE WEATHER
SHOULD INCREASE ALONG THE BOUNDARY FRIDAY AFTERNOON AND EVENING. THE
SHEAR VALUES ARE QUITE RESPECTABLE ALONG WITH PLENTY OF CAPE AND
DCAPE. DAMAGING WINDS WOULD CERTAINLY BE THE PRIMARY FACTOR AS WE
HAVE SEEN TO OUR NORTH RECENTLY. IN ADDITION...THERE SHOULD BE A
RATHER EXTENSIVE AREA OF SHOWERS PASS ACROSS NORTHERN MN ON FRIDAY
AS STRONG MID LEVEL FRONTOGENESIS DEVELOPS ALONG WITH A RATHER
STRONG SIGNAL SEEN IN THE DIFFERENTIAL DIVERGENCE.
THE BOUNDARY WILL THEN SETTLE SOUTH FRIDAY NIGHT AND SATURDAY WITH
PRECIPITATION CHANCES SLOWLY DIMINISHING FROM NORTHWEST TO
SOUTHEAST BY LATE IN THE DAY ON SATURDAY. DRY WEATHER IS INDICATED
FOR SATURDAY NIGHT THROUGH THURSDAY OF NEXT WEEK AS THE UPPER
RIDGE SLIPS WEST AND NORTHWEST FLOW DEVELOPS OVER OUR AREA. HIGHS
WILL BE MUCH CLOSER TO NORMAL DURING THIS PERIOD WITH LOWER TO
MIDDLE 80S FORECAST.
&&
.AVIATION... /18Z TAF ISSUANCE/
MAIN AVIATION CONCERN IS LEFTOVER BOUNDARY THAT HAS MOVED AS FAR
SOUTH AS KMKT EARLY THIS AFTN. THIS BOUNDARY WILL BE THE FOCUS OF
TSRA DURING THE AFTN/EVENING AS THE BOUNDARY STALLS NEAR THE MN/IA
BORDER...AND MOVES BACK NORTHWARD TONIGHT. ALL OTHER MPX TAF SITES
WILL LIKELY BE SHRA/TSRA FREE UNTIL THE BOUNDARY MOVES NORTHWARD
THIS EVENING.
BASED ON THE LATEST HRRR AND HOW UNSTABLE THE ATMOSPHERE REMAINS
ACROSS FAR SOUTHERN MN...HAVE DECIDED TO ADD VCSH AT RWF AFT 20Z.
WITH THE LATER HRRR FORECASTING SHRA/TSRA NEAR RWF BY
20-22Z...THIS TAF MAY NEED TO BE UPDATED WITH TSRA/VCTS AND CBS.
WILL SEE HOW CONVECTION DEVELOPS THIS AFTN BEFORE CHG ANYTHING. AS
FOR AXN/STC...AS THE BOUNDARY MOVES NORTHWARD...AND A SUBTLE WAVE
MOVES ACROSS THE NORTHERN PLAINS...SHRA/TSRA SHOULD BEGIN TO
DEVELOP IN THE DAKOTAS...AND SPREAD E/NE ACROSS WESTERN/CENTRAL MN
AFT MIDNIGHT. HAVE INTRODUCE VCSH...AND PROB30 AFT 12Z FOR BOTH
STC/AXN. LATER SHIFTS CAN UPDATE HOW LOW CIGS/VSBYS GET BASED ON
RADAR TRENDS. RNH/EAU WILL LIKELY BE SHRA/TSRA FREE UNTIL AFT
18Z/06. WNDS WILL REMAIN FROM THE NORTH...OR BECOME N/NNE THIS
AFTN WITH SOME GUSTS...ESPECIALLY EARLY AT STC/RWF/AXN. WNDS WILL
SHIFT TO THE NE/ENE OVERNIGHT...THEN E/SE AT RWF/RNH/EAU DURING
THE DAY.
MSP...KEPT TAF CLR OF SHRA/TSRA UNTIL AFT 9Z WHICH THE POTENTIAL
OF ELEVATED CONVECTION DEVELOPS AS THE BOUNDARY MOVES NORTHWARD.
BEST POTENTIAL OF SHRA/TSRA WILL COME AFT 00Z/07. WNDS WILL
GENERALLY BE FROM THE N/NNE EARLY THIS AFTN...THEN SLOWLY BECOMING
ENE/E OVERNIGHT...THE SE/SW BY FRIDAY AFTN AS THE MAIN SFC WARM
FRONT MOVES BACK NORTH OF THE TERMINAL SITE. WILL INTRODUCE VCSH
AFT 9Z DUE TO SOME UNCERTAINTIES OF THE ELEVATED CONVECTION...BUT
CIGS/VSBYS SHOULD REMAIN VFR.
.FRIDAY EVENING...VFR/MVFR. CHC SHWRS/TSTMS. SHIFTING WINDS...BECOMING NE
5-10 KT.
.SATURDAY...VFR/MVFR. CHC SHWRS/TSTMS. WINDS NE 5-10 KT.
.SUNDAY...VFR. WINDS NE BECOMING NW AROUND 5 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...EXCESSIVE HEAT WARNING UNTIL 7 PM CDT FRIDAY FOR BLUE EARTH-
BROWN-DAKOTA-FARIBAULT-FREEBORN-GOODHUE-LE SUEUR-MARTIN-
NICOLLET-RICE-SCOTT-STEELE-WASECA-WATONWAN.
EXCESSIVE HEAT WARNING UNTIL 10 PM CDT THIS EVENING FOR ANOKA-
CARVER-CHISAGO-HENNEPIN-ISANTI-MCLEOD-MEEKER-RAMSEY-REDWOOD-
RENVILLE-SHERBURNE-SIBLEY-WASHINGTON-WRIGHT.
WI...EXCESSIVE HEAT WARNING UNTIL 7 PM CDT FRIDAY FOR EAU CLAIRE-
PEPIN-PIERCE.
EXCESSIVE HEAT WARNING UNTIL 10 PM CDT THIS EVENING FOR BARRON-
CHIPPEWA-DUNN-POLK-RUSK-ST. CROIX.
&&
$$
RAH/JLT
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1225 PM CDT THU JUL 5 2012
.DISCUSSION...
SCATTERED TSTMS...A FEW BORDERLINE SEVERE DEVELOPED IN PAST COUPLE
OF HOURS IN MOIST PLUME EXTENDING ACROSS S MN. ATMOS VERY UNSTABLE
IN MID LEVELS WITH STRONG LAPSE RATES WHERE AXIS OF K INDEX VALUES
AROUND 40. MOST OF THIS ROUND OF CONVECTION SHUD BE OVER BY 0900
AS 850 MB TROF MOVES THRU AREA AND MOISTURE TRANSPORT VECTORS
BECOME DIRECTED MORE WNW TO ESE.
MAIN FORECAST ISSUES WILL BE WITH CONVECTIVE CHANCES INTO SATURDAY AS
WELL AT THE EXCESSIVE HEAT WARNING WHICH IS CURRENTLY IN PLACE.
AT THE SURFACE THE ADVERTISED WEAK COOL FRONT HAS BEEN MAKING
PROGRESS OVERNITE AND CURRENTLY LIES FROM ARND DLH TO NEAR ULM.
BEGINNING TO SEE SURFACE DEW POINTS FALL ACROSS NW MN IN THE WAKE
OF THE FRONT. NICE SURFACE PRESSURE RISE AREA BEHIND FRONT WILL
CONTINUE TO PUSH IT ALONG THIS MORNING...BUT PROGRESS SHOULD SLOW
THIS AFTERNOON AS 500 MB HEIGHT BEGIN TO RISE. AFTERNOON
TEMPERATURES WILL BE SEVERAL DEGREES COOLER ACROSS CENTRAL MN
TODAY WITH LOWER RH. THUS DROPPED THE THE HEAT WARNING ACROSS
ABOUT A DOZEN COUNTIES ACROSS CENTRAL INTO WC MN. WITH FRONT
REBOUNDING BACK NORTH AS A WARM FRONT LATE TONIGHT AND
FRIDAY...EXTENDED THE HEAT WARNING UNTIL 7 PM FRIDAY ACROSS S MN
TOWARD EAU.
AIR MASS WILL VERY VERY UNSTABLE TODAY ACROSS S CWA WITH SBCAPE
AROUND 4000 J/KG. MID LEVEL TEMPS VERY WARM WHICH WILL PROVIDE
SOME CAPPING...BUT WITH ATMOS SO UNSTABLE AND BOUNDARY IN AREA ANY
STORMS WHICH DO DEVELOP COULD BECOME SEVERE.
SHOULD SEE TSTMS DEVELOP TONIGHT IN THE DKTS AND THEN MOVE MAINLY
INTO CENTRAL MN IN INCREASING MID LEVEL THETA E ADVECTION. VERY
IMPRESSIVE 850 MB THERMAL GRADIENT ACROSS CENTRAL MN ON FRIDAY
WITH WARM FRONT SETTING UP ACROSS S MN. WITH PWATS REBOUNDING TO
1.75 TO 2 INCHES LOOKS LIKE A GOOD SETUP FOR HEAVY RAINS ACROSS
CENTRAL MN FRIDAY AFTN/EVENING AS SURFACE LOW TRACKS ACROSS S MN.
FALLING MID LEVEL TEMPS SHOULD ALSO ALLOW PCPN TO DEVELOP
SOUTHWARD FRIDAY NIGHT INTO S CWA AS 1000-500 MB THICKNESS FIELD
BECOMES DIFFLUENT AND ORIENTED TOWARD THE SE ACROSS THAT AREA.
SEVERE THREAT CERTAINLY ALSO POSSIBLE WITH BOUNDARY PRESENT AND
INCREASING 0-6 KM BULK SHEAR.
NAM/GFS DROP PCPN SE OF AREA BY MID DAY SATURDAY AS HIGH PRESSURE
BUILDS INTO AREA...BUT ECMWF KEEPS PCPN GOING S AREAS THROUGH SAT
NIGHT. TRIMMED BACK POPS N AREAS AS MOST AREAS SHOULD BE FAR ENUF
INTO NW FLOW TO MINIMIZE PCPN THREAT.
NW FLOW THEN CONTINUES FOR BALANCE OF FORECAST PERIOD BRINGING
SEASONABLE TEMPERATURES AND LITTLE CHC OF PCPN.
&&
.AVIATION.../18Z TAF ISSUANCE/
MAIN AVIATION CONCERN IS LEFTOVER BOUNDARY THAT HAS MOVED AS FAR
SOUTH AS KMKT EARLY THIS AFTN. THIS BOUNDARY WILL BE THE FOCUS OF
TSRA DURING THE AFTN/EVENING AS THE BOUNDARY STALLS NEAR THE MN/IA
BORDER...AND MOVES BACK NORTHWARD TONIGHT. ALL OTHER MPX TAF SITES
WILL LIKELY BE SHRA/TSRA FREE UNTIL THE BOUNDARY MOVES NORTHWARD
THIS EVENING.
BASED ON THE LATEST HRRR AND HOW UNSTABLE THE ATMOSPHERE REMAINS
ACROSS FAR SOUTHERN MN...HAVE DECIDED TO ADD VCSH AT RWF AFT 20Z.
WITH THE LATER HRRR FORECASTING SHRA/TSRA NEAR RWF BY
20-22Z...THIS TAF MAY NEED TO BE UPDATED WITH TSRA/VCTS AND CBS.
WILL SEE HOW CONVECTION DEVELOPS THIS AFTN BEFORE CHG ANYTHING. AS
FOR AXN/STC...AS THE BOUNDARY MOVES NORTHWARD...AND A SUBTLE WAVE
MOVES ACROSS THE NORTHERN PLAINS...SHRA/TSRA SHOULD BEGIN TO
DEVELOP IN THE DAKOTAS...AND SPREAD E/NE ACROSS WESTERN/CENTRAL MN
AFT MIDNIGHT. HAVE INTRODUCE VCSH...AND PROB30 AFT 12Z FOR BOTH
STC/AXN. LATER SHIFTS CAN UPDATE HOW LOW CIGS/VSBYS GET BASED ON
RADAR TRENDS. RNH/EAU WILL LIKELY BE SHRA/TSRA FREE UNTIL AFT
18Z/06. WNDS WILL REMAIN FROM THE NORTH...OR BECOME N/NNE THIS
AFTN WITH SOME GUSTS...ESPECIALLY EARLY AT STC/RWF/AXN. WNDS WILL
SHIFT TO THE NE/ENE OVERNIGHT...THEN E/SE AT RWF/RNH/EAU DURING
THE DAY.
MSP...KEPT TAF CLR OF SHRA/TSRA UNTIL AFT 9Z WHICH THE POTENTIAL
OF ELEVATED CONVECTION DEVELOPS AS THE BOUNDARY MOVES NORTHWARD.
BEST POTENTIAL OF SHRA/TSRA WILL COME AFT 00Z/07. WNDS WILL
GENERALLY BE FROM THE N/NNE EARLY THIS AFTN...THEN SLOWLY BECOMING
ENE/E OVERNIGHT...THE SE/SW BY FRIDAY AFTN AS THE MAIN SFC WARM
FRONT MOVES BACK NORTH OF THE TERMINAL SITE. WILL INTRODUCE VCSH
AFT 9Z DUE TO SOME UNCERTAINTIES OF THE ELEVATED CONVECTION...BUT
CIGS/VSBYS SHOULD REMAIN VFR.
.FRIDAY EVENING...VFR/MVFR. CHC SHWRS/TSTMS. SHIFTING WINDS...BECOMING NE
5-10 KT.
.SATURDAY...VFR/MVFR. CHC SHWRS/TSTMS. WINDS NE 5-10 KT.
.SUNDAY...VFR. WINDS NE BECOMING NW AROUND 5 KT.
..JLT..
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...EXCESSIVE HEAT WARNING UNTIL 7 PM CDT FRIDAY FOR BLUE EARTH-
BROWN-DAKOTA-FARIBAULT-FREEBORN-GOODHUE-LE SUEUR-MARTIN-
NICOLLET-RICE-SCOTT-STEELE-WASECA-WATONWAN.
EXCESSIVE HEAT WARNING UNTIL 10 PM CDT THIS EVENING FOR ANOKA-
CARVER-CHISAGO-HENNEPIN-ISANTI-MCLEOD-MEEKER-RAMSEY-REDWOOD-
RENVILLE-SHERBURNE-SIBLEY-WASHINGTON-WRIGHT.
WI...EXCESSIVE HEAT WARNING UNTIL 7 PM CDT FRIDAY FOR EAU CLAIRE-
PEPIN-PIERCE.
EXCESSIVE HEAT WARNING UNTIL 10 PM CDT THIS EVENING FOR BARRON-
CHIPPEWA-DUNN-POLK-RUSK-ST. CROIX.
&&
$$
BAP/JLT
AREA FORECAST DISCUSSION
NWS HASTINGS NE
101 PM CDT THU JUL 5 2012
.AVIATION...18Z KGRI TAF. UPPER LEVEL HIGH PRESURE IS IN CONTROL
ONCE AGAIN. THE BOUNDARY THAT PRODUCED SHOWERS AND SOME
THUNDERSHOWERS JUST NORTH OF THE TERMINAL EARLY THIS MORNING HAS
SHIFTED NORTH AND WILL REMAIN FAR ENOUGH NORTH TO KEEP CONVECTIVE
ACTIVITY OUT OF THE LOCAL AREA. WIND SPEED WILL SUBSIDE SOME
TONIGHT...BUT NOT ENOUGH TO INTRODUCE ANOTHER FM GROUP. WIND SPEED
WILL INCREASE AGAIN TOWARD NOON FRIDAY WITH WIND DIRECTION
SHIFTING A BIT MORE TO THE SOUTH SOUTHWEST AHEAD OF A DEVELOPING
SURFACE TROUGH TO THE WEST.
&&
.PREV DISCUSSION... /ISSUED 1112 AM CDT THU JUL 5 2012/
UPDATE...UPDATED THE FORECAST AS CONVECTIVE ACTIVITY IS NOW
CONFINED TO THE FAR NORTHERN PART OF THE CWA AS THE BOUNDARY
SHIFTS NORTH. RAISED CHANCES OF PRECIPITATION A BIT IN THE FAR
NORTH...BUT BY MID TO LATE AFTERNOON...ANY PRECIPITATION SHOULD
MOVE NORTH OF THE CWA AS THE BOUNDARY MOVES NORTH.
PREV DISCUSSION... /ISSUED 643 AM CDT THU JUL 5 2012/
UPDATE...A SMALL AREA OF SHOWERS...MAYBE A FEW VERY WEAK
THUNDERSTORMS CONTINUES TO LIFT NORTH EARLY THIS MORNING...MAINLY
ALONG THE HIGHWAY 281 CORRIDOR NEAR GRAND ISLAND. WE EVEN MEASURED
A FEW RATHER UNEXPECTED HUNDREDTHS OF AN INCH HERE AT THE WFO.
HAVE LINGERED A 20 PERCENT STORM CHANCE FOR ALL AREAS ALONG/NORTH
OF INTERSTATE 80 THROUGH THE REST OF THE MORNING...BUT IN ALL
LIKELIHOOD THIS ACTIVITY WILL EITHER DISSIPATE OR MOVE OUT OF THE
AREA WELL BEFORE NOON. MESO-ANALYSIS INDICATES THIS CONVECTION IS
RATHER WELL TIED TO THE EXIT CONVERGENT REGION OF A 30KT
SOUTHWESTERLY LOW LEVEL JET...WHICH SHOULD GRADUALLY WEAKEN AND
FOCUS FARTHER NORTH AS THE DAY WEARS ON. AS STATED IN EARLIER
DISCUSSION...WILL DEFER TO DAY SHIFT TO CLEAN UP LINGERING POPS
FROM THIS MORNING...AND POTENTIALLY REMOVE THE SLIGHT POP FROM THE
FAR NORTHERN CWA FOR THE AFTERNOON HOURS. INTERESTINGLY...THE
LATEST HRRR REFLECTIVITY PROG HINTS AT A FEW STORMS FLARING UP
LATE THIS AFTERNOON IN THE WESTERN CWA...WHICH IS ALSO SUPPORTED
BY THE 00Z 4KM WRF-NMM...BUT AT THIS POINT AM NOT FULLY BUYING
INTO IT AS THE PRIMARY LOW LEVEL CONVERGENCE ZONE SHOULD BE
FOCUSED NORTH OF THE AREA BY THEN.
PREV DISCUSSION... /ISSUED 541 AM CDT THU JUL 5 2012/
AVIATION...12Z KGRI TAF...VFR CONDITIONS ARE EXPECTED TO CONTINUE
AT KGRI FOR THE NEXT 24 HOURS. EXPECT A FEW -SHRAS TO SKIRT THE
TERMINAL THROUGH THE EARLY MORNING HOURS...WITH BOTH CIGS AND
VSBYS EXPECTED TO REMAIN VFR THROUGHOUT. SOUTHERLY WINDS NEAR
10KTS THIS MORNING WILL INCREASE TO NEAR 18KTS BY 17Z...WITH ONLY
A FEW-SCT MID/HIGH LEVEL CLOUDS EXPECTED THROUGH THE AFTERNOON
HOURS.
PREV DISCUSSION... /ISSUED 450 AM CDT THU JUL 5 2012/
SHORT TERM...THROUGH SATURDAY NIGHT. FOR THE NEXT FEW
DAYS...CONCERNS REMAIN PRETTY MUCH THE SAME...AND CENTERED AROUND
HEAT AND FIRE WEATHER. HOWEVER...THE BEGINNING STAGES OF A NOTABLE
RETURN TO COOLER TEMPERATURES WILL GET UNDERWAY BY SATURDAY...WITH
AT LEAST SLIGHT THUNDERSTORM CHANCES IN THE MIX AS EARLY AS
SATURDAY NIGHT. FOR FIRE WEATHER INFO...PLEASE REFER TO THE
SEPARATE SECTION BELOW.
08Z OBJECTIVE SURFACE ANALYSIS REVEALS A TROUGH AXIS/WEAK COLD
FRONT STRETCHED FROM EASTERN CO ACROSS WESTERN/NORTH CENTRAL NEB
INTO SOUTHEAST SD. WITH THE CWA POSITIONED JUST EAST OF THIS
FEATURE...MOST AREAS ARE EXPERIENCING SOUTHERLY BREEZES AROUND 10
MPH...WITH SOME HIGHER GUSTS ESPECIALLY IN KS ZONES. THE
COMBINATION OF BREEZES AND HIGH LEVEL CLOUD COVER IS KEEPING PRE-
DAWN TEMPERATURES WELL UP BETWEEN 73-80 MOST AREAS. AS WAS PRETTY
MUCH EXPECTED 24 HOURS AGO...A NARROW AXIS OF THUNDERSTORMS FLARED
UP DURING THE AFTERNOON/EVENING ALONG THE SURFACE
BOUNDARY...PRIMARILY JUST NORTHWEST OF THE CWA BUT AT LEAST
CLIPPING FAR WESTERN DAWSON COUNTY. EVEN AT THIS HOUR...THIS
FAIRLY WEAK STORM CLUSTER PERSISTS ACROSS SEVERAL SOUTHWEST NEB
COUNTIES...BUT SAFELY OUTSIDE THE CWA. ALOFT...EARLY MORNING WATER
VAPOR IMAGERY AND SHORT TERM MODEL DATA PLACE THE HEART OF THE
EXPANSIVE CENTRAL CONUS MID LEVEL RIDGE AXIS OVER MO...WITH WEAK
SHORTWAVE ENERGY RIDING AROUND THE NORTHWEST PERIPHERY OF THE
RIDGE...ALONG WITH SUPPORT FROM A FAIRLY IMPRESSIVE 40+KT 850MB
LOW LEVEL JET AXIS TEAMING UP TO KEEP THE ONGOING SOUTHWEST NEB
STORMS GOING.
STARTING WITH THE FIRST FEW HOURS EARLY THIS MORNING...MADE A
LAST MINUTE DECISION REGARDING POPS...AS LATEST RADAR TRENDS LEND
LITTLE EVIDENCE OF WIDESPREAD CONVECTION PUSHING BACK EAST-
NORTHEAST TOWARD THE CWA...WHICH IS SOMEWHAT CONTRADICTORY TO THE
QPF/REFLECTIVITY PROGS FROM MODELS SUCH AS THE 06Z NAM AND 05Z
HRRR...WHICH STILL SHOW STORMS POTENTIALLY CLIPPING PARTS OF THE
NORTHERN CWA AS THE LOW LEVEL JET CONVERGENCE ZONE AND THE SURFACE
BOUNDARY START TO LIFT BACK TO THE NORTH. ADDING TO THE
DILEMMA...AS I TYPE THIS...BRAND NEW ISOLATED SHOWER/STORM
DEVELOPMENT IS TAKING PLACE NEAR THE HIGHWAY 6/I-80 CORRIDORS
WITHIN THE LOW LEVEL JET AXIS...WHICH COULD REQUIRE AN EXPANSION
OF AT LEAST SLIGHT CHANCE POPS FOR MORE OF MAINLY THE NORTHERN 1/2
OF THE CWA THAN EARLIER EXPECTED. NO MATTER WHAT...MORNING
CONVECTION SHOULD REMAIN FAIRLY SPARSE IN COVERAGE...AND STRONG TO
SEVERE STORMS SHOULD NOT BE AN ISSUE. HEADING INTO THE AFTERNOON
HOURS...THE ONE WILD CARD FROM THE ONGOING MORNING CONVECTION IS
HOW MUCH...IF EVEN AT ALL...IT SLOWS THE NORTHWARD PROGRESSION OF
THE EFFECTIVE SURFACE WARM FRONT. ALTHOUGH THE SOUTHERN HALF OF
THE CWA SHOULD HAVE NO TROUBLE KEEPING PREVAILING SOUTHERLY
BREEZES...NORTHERN AREAS MAY TEND TO STAY A BIT MORE EAST-
SOUTHEASTERLY FOR A PORTION OF THE DAY. WAS VERY TEMPTED TO PULL
OUT THE SLIGHT CHANCE POP ACROSS THE FAR NORTH DURING THE
AFTERNOON...AS CONSENSUS OF VARIOUS MODELS FOCUSES AFTERNOON
CONVECTION CLOSER TO THE NEB/SD BORDER. HOWEVER...WITH THE LIFTING
BOUNDARY STILL SO CLOSE BY...AND FAIRLY WEAK CAPPING AS DEEP
MIXING COMMENCES...WILL LIKELY PLAY IT SAFE AND LET DAY SHIFT
DECIDE LATER THIS MORNING IF ITS SAFE TO FULLY PULL STORM MENTION
FROM THE FAR NORTHERN CWA. EVEN IF AFTERNOON STORMS WOULD CLIP THE
NORTH...NOT EXPECTING SEVERE IN SUCH A CONTINUED WEAK SHEAR
REGIME...ALTHOUGH SMALL HAIL AND GUSTY WINDS OF 50+ MPH CANNOT BE
RULED OUT. TURNING TO TEMPERATURES...OTHER THAN POSSIBLE
COMPLICATING EFFECTS OF CONVECTIVE OUTFLOW SLOWING THE WARM SURGE
IN NORTHERN COUNTIES...SEE NO REASON TO BELIEVE WHY TEMPS TODAY
SHOULDN/T BE ALMOST IDENTICAL TO THOSE OF YESTERDAY GIVEN VERY
LITTLE CHANGE IN THE LOWER LEVEL THERMAL PROFILE. THUS THE HIGH
TEMP GRID IS ESSENTIALLY A COPY-PASTE FROM YESTERDAY...WITH MOST
OF THE CWA INTO THE 100-105 RANGE...EXCEPT FOR UPPER 90S IN
NORTHEAST ZONES SUCH AS POLK/YORK WHERE DEWPOINTS SHOULD HOLD
HIGHER. ALSO LIKE YESTERDAY...HEAT INDEX VALUES SHOULD EASILY
REACH THE 103-105 RANGE IN MANY AREAS...AND LOCALLY HIGHER
ESPECIALLY IN THE CENTRAL/NORTHEAST. AS A RESULT...AND IN ORDER TO
BETTER COLLABORATE WITH PREVIOUSLY ISSUED HEADLINES BY OAX AND LBF
OFFICES...HAVE GONE AHEAD AND ISSUED A CWA-WIDE HEAT ADVISORY NOT
ONLY FOR THIS AFTERNOON BUT ALSO LASTING THROUGH FRIDAY.
FOR TONIGHT...KEPT OUT ALL STORM MENTION...AS THE SURFACE BOUNDARY
AND ALSO LOW LEVEL JET CONVERGENCE SHOULD FOCUS WELL TO THE NORTH
BY THEN...KEEPING THE BEST STORM CHANCES CLOSER TO THE SD BORDER
AND POINTS NORTH. MADE LITTLE CHANGE TO OVERNIGHT LOW TEMPS...WITH
MOST AREAS BETWEEN 72-76...BUT THIS COULD EASILY BE A FEW DEGREES
TOO COOL IN SOME AREAS.
FOR FRIDAY...AS ALREADY MENTIONED...CONTINUED THE HEAT ADVISORY
GOING THROUGH THE AFTERNOON AND EARLY EVENING...AS ONCE AGAIN JUST
SEE LITTLE REASON TO BELIEVE THAT TEMPERATURES WON/T BE AT LEAST
AS HOT AS YESTERDAY/TODAY. IN FACT...WITH THE NAM SUGGESTING THAT
WINDS WILL TAKE ON MORE OF A SOUTHWESTERLY COMPONENT AHEAD OF AN
APPROACHING COLD FRONT...ACTUAL AIR TEMPERATURES FRIDAY COULD BE
EVEN HOTTER THAN CURRENTLY ADVERTISED. TAKING THE MODEL AT FACE
VALUE...EVEN SEVERAL NEBRASKA COUNTIES COULD MAKE A RUN AT OR
EXCEED 105 DEGREES...WITH 105-108 COMMON IN KANSAS. OF
COURSE...THESE VERY HOT READINGS WOULD ALSO DEPEND ON A MIXING OUT
OF DEWPOINTS DURING THE DAY INTO THE 50S-LOWER 60S. ALTHOUGH AM
NOT GOING FULL BORE WITH THE NAM SOLUTION YET...DID BUMP UP HIGHS
FRIDAY 1-3 DEGREES FROM PREVIOUS FORECAST IN MOST AREAS...WITH THE
MAJORITY OF THE CWA AT LEAST INTO THE 100-104 RANGE. AS FOR STORM
CHANCES...LEFT THE ENTIRE DAY AND EVENING DRY...ALTHOUGH THE
LATEST 06 NAM IS NOW BECOMING MORE SUGGESTIVE THAN PREVIOUS RUNS
OF CONVECTION FIRING ALONG A WELL-DEFINED COLD FRONT NEAR THE
NORTHWEST EDGE OF THE CWA LATE IN THE AFTERNOON/EVENING...SIMILAR
TO WHAT JUST HAPPENED WEDNESDAY. HOWEVER...THE NAM SEEMS TO BE A
BIT OF A FAST OUTLIER ON THE SPEED OF THE INVADING BOUNDARY...WITH
THE ECMWF HANGING CONVECTION MOSTLY JUST OFF TO THE
NORTH/NORTHWEST. WILL HAVE TO KEEP AN EYE ON THIS THOUGH. IF
STORMS ARE ABLE TO FORM IN THE NORTHWEST...A FEW STRONG TO
MARGINALLY SEVERE CELLS CANNOT BE RULED OUT...OWING TO SLIGHTLY
STRONGER FORCING AND DEEP LAYER SHEAR CLIMBING CLOSER TO 30KT.
WILL HOLD OFF FOR NOW ON INTRODUCING ANY STORM MENTION FOR FRIDAY
AFTERNOON/NIGHT...BUT THIS COULD BE INTRODUCED DURING THE NEXT FEW
FORECAST CYCLES IF TRENDS HOLD. WHETHER STORMS FORM OR
NOT...CONFIDENCE IS FAIRLY HIGH THAT THE FIRST LEGITIMATE SUMMER
COLD FRONT IN AWHILE WILL MAKE STEADY PROGRESS INTO THE CWA FRIDAY
NIGHT.
SATURDAY...EVEN THE SLOWER ECMWF SOLUTION BRINGS A COLD FRONT AT
LEAST HALFWAY THROUGH THE CWA...WITH BOTH THE NAM/GFS SUGGESTING
IT WILL MAKE IT ALL THE WAY THROUGH THE CWA INTO CENTRAL
KANSAS...WITH NORTHEAST WINDS CWA-WIDE IN ITS WAKE. OBVIOUSLY THE
SPEED/STRENGTH OF THIS FRONTAL INVASION WILL HAVE A BIG IMPACT ON
HIGH TEMPS...AND CONFIDENCE IS A BIT LOWER THAN USUAL FOR ONLY
BEING A FEW DAYS AWAY...WITH ABOUT A 10 DEGREE SPREAD BETWEEN
MODEL SOLUTIONS. TAKING A CONSENSUS APPROACH...NUDGED DOWN
PREVIOUS FORECAST HIGHS 2-3 DEGREES MOST AREAS...NOW CALLING FOR
HIGHS RANGING FROM ONLY UPPER 80S-LOW 90S IN NEB ZONES...AND MID-
UPPER 90S IN KS. IF THIS PANS OUT...WE SHOULD BE OFFICIALLY DONE
WITH THE PROLONGED ROUGHLY 10-DAY STRETCH OF WELL ABOVE NORMAL
HEAT. ALTHOUGH HAVE CONTINUED TO KEEP THE FORECAST DRY FOR
SATURDAY...POPS MAY EVENTUALLY NEED ADDED HERE AS
WELL...ESPECIALLY IF THE FRONT DOES NOT PASS ALL THE WAY SOUTH OF
THE CWA BY THE AFTERNOON HOURS AS THE NAM SUGGESTS.
BY SATURDAY NIGHT...THE TRANSITION TO A MORE NORTHWESTERLY FLOW
REGIME REALLY STARTS TO SHOW ITS HAND...AS THE CENTER OF THE MID-
UPPER RIDGE AXIS RETROGRADES WEST TO OVER THE ROCKIES VERSUS THE
CURRENT CENTRAL/EASTERN PLAINS POSITION. ALTHOUGH CONFIDENCE IN
THE DETAILS IS LOW...VARIOUS MODELS SUGGEST STORMS COULD IMPACT
PARTS OF THE CWA SAT NIGHT...AND HAVE RE-INTRODUCED A SLIGHT POP
ACROSS MAINLY THE SOUTHWEST 2/3 OF THE CWA FOR NOW.
LONG TERM...STARTING 12Z SUNDAY...THE UPPER LEVEL RIDGE IS
ANTICIPATED TO AMPLIFY OVER THE INTERMOUNTAIN WEST EARLY NEXT WEEK
AS A TROUGH OF LOW PRESSURE DIGS ACROSS THE NORTHEAST. THIS WILL
RESULT IN A GENERALLY NORTHWESTERLY FLOW PATTERN ALOFT ACROSS THE
NORTHERN AND CENTRAL PLAINS FOR SEVERAL DAYS...UNTIL LATE IN THE
PERIOD...WHEN THE RIDGE OVER THE INTERMOUNTAIN WEST BEGINS TO SHIFT
FURTHER EASTWARD.
IN THE LOW LEVELS OF THE ATMOSPHERE...EXPECT THE COLD FRONT THAT IS
FORECAST TO REACH THE LOCAL AREA ON SATURDAY...TO LINGER NEAR THE
KS/NE STATE LINES ON SUNDAY...EVENTUALLY PUSHING SOUTH OF THE LOCAL
AREA BY SUNDAY AFTERNOON OR MONDAY. BOTH EC AND GFS TRACK THIS FRONT
ACROSS THE LOCAL AREA AND TO THE SOUTH BY LATE SUNDAY EVENING/EARLY
MONDAY MORNING...AND DUE TO THIS SLIGHT VARIATION IN
TIMING...DECIDED TO KEEP SOME SMALL MENTION OF POPS INTO THE DAY
MONDAY...WITH SKIES THEN CLEARING AND DRY WEATHER EXPECTED
THEREAFTER.
WHILE THERE WILL BE A CHANCE FOR SOME MUCH NEEDED PRECIPITATION WITH
THIS PASSING BOUNDARY...INSTABILITY AND SHEAR BOTH APPEAR VERY
MARGINAL...AND WIDESPREAD SEVERE WEATHER IS NOT ANTICIPATED AT THIS
TIME. AT THIS POINT...IT APPEARS COOLING TEMPERATURES WILL BE AS
WELCOME AS RAIN CHANCES OVER THE UPCOMING WEEKEND...WITH 850 MB
TEMPS FORECAST TO DROP AS MUCH AS 10C DEPENDING ON WHICH MODEL YOU
ARE LOOKING AT. WITH COOLER TEMPS ALOFT...SOME ANTICIPATED CLOUDS
AND AT LEAST SPOTTY RAINFALL...WENT AHEAD AND LOWERED TEMPS SUNDAY
AFTERNOON BELOW SEASONAL NORMS FOR THE FIRST TIME IN A WHILE...WITH
CONTINUED SEASONABLY COOL WEATHER THEN ANTICIPATED THROUGH THE END
OF NEXT WEEK. BESIDES LOWERING TEMPS A BIT ON SUNDAY AND TRIMMING
POPS A SMALL AMOUNT MONDAY AFTERNOON...NO OTHER SIGNIFICANT CHANGES
NECESSARY TO BLENDED MODEL SOLUTIONS THIS MORNING.
FIRE WEATHER...ALTHOUGH THE COMBINATION OF RELATIVE HUMIDITY
DROPPING TO AROUND 20 PERCENT AND SUSTAINED WINDS NEAR 20
MPH/GUSTS AROUND 25 MPH WILL AGAIN PROMOTE AT LEAST NEAR-CRITICAL
FIRE DANGER ACROSS SEVERAL SOUTHERN COUNTIES THIS
AFTERNOON...OPTED TO HOLD OFF ON A FORMAL RED FLAG WARNING THIS
TIME AROUND...AS CONDITIONS SHOULD BE VERY SIMILAR TO
YESTERDAY...DURING WHICH RED FLAG CRITERIA STRUGGLED TO
MATERIALIZE FOR 3 OR MORE HOURS. HOWEVER...IT COULD STILL BE A
CLOSE CALL...AND SOMETHING THAT DAY SHIFT WILL HAVE TO MONITOR.
DESPITE THE LACK OF A FORMAL RED FLAG WARNING AT THIS
TIME...EXTREME FIRE DANGER WILL BE HIGHLIGHTED FOR SEVERAL
COUNTIES IN THE GRASSLAND FIRE DANGER PRODUCT...AND WILL CONTINUE
TO MENTION IN THE HAZARDOUS WEATHER OUTLOOK. TURNING TO
FRIDAY...THERE MIGHT ACTUALLY BE GREATER FIRE CONCERNS ON THIS
DAY...AS WINDS TURN MORE SOUTHWESTERLY AND SPREAD SUB-20 PERCENT
RH POTENTIAL FARTHER NORTHEAST...POTENTIALLY INTO ALL AREAS
SOUTHWEST OF A LEXINGTON-BELOIT LINE. IT APPEARS THE LIMITING
FACTOR FOR EVENTUAL RED FLAG ISSUANCE COULD BE WIND SPEEDS...AS
CURRENTLY HAVE SUSTAINED SPEEDS AVERAGING CLOSER TO 15 MPH VERSUS
20 MPH. IF WINDS WERE EXPECTED TO BE ROUGHLY 5 MPH HIGHER...WOULD
HAVE CONSIDERED ISSUING A FIRE WEATHER WATCH...AND DAY SHIFT WILL
HAVE TO TAKE ANOTHER LOOK TO SEE IF AT LEAST A WATCH MIGHT BE
WARRANTED FOR FRIDAY. FORTUNATELY...THE INVASION OF A COOLER
AIRMASS FOR SATURDAY AND THE NEXT SEVERAL DAYS THEREAFTER SHOULD
AT LEAST EASE UP THE UNSEASONABLY HIGH FIRE DANGER WE HAVE HAD
LATELY.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...HEAT ADVISORY UNTIL 9 PM CDT FRIDAY FOR NEZ039>041-046>049-
060>064-072>077-082>087.
KS...HEAT ADVISORY UNTIL 9 PM CDT FRIDAY FOR KSZ005>007-017>019.
&&
$$
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1112 AM CDT THU JUL 5 2012
.UPDATE...UPDATED THE FORECAST AS CONVECTIVE ACTIVITY IS NOW
CONFINED TO THE FAR NORTHERN PART OF THE CWA AS THE BOUNDARY
SHIFTS NORTH. RAISED CHANCES OF PRECIPITATION A BIT IN THE FAR
NORTH...BUT BY MID TO LATE AFTERNOON...ANY PRECIPITATION SHOULD
MOVE NORTH OF THE CWA AS THE BOUNDARY MOVES NORTH.
&&
.PREV DISCUSSION... /ISSUED 643 AM CDT THU JUL 5 2012/
UPDATE...A SMALL AREA OF SHOWERS...MAYBE A FEW VERY WEAK
THUNDERSTORMS CONTINUES TO LIFT NORTH EARLY THIS MORNING...MAINLY
ALONG THE HIGHWAY 281 CORRIDOR NEAR GRAND ISLAND. WE EVEN MEASURED
A FEW RATHER UNEXPECTED HUNDREDTHS OF AN INCH HERE AT THE WFO.
HAVE LINGERED A 20 PERCENT STORM CHANCE FOR ALL AREAS ALONG/NORTH
OF INTERSTATE 80 THROUGH THE REST OF THE MORNING...BUT IN ALL
LIKELIHOOD THIS ACTIVITY WILL EITHER DISSIPATE OR MOVE OUT OF THE
AREA WELL BEFORE NOON. MESO-ANALYSIS INDICATES THIS CONVECTION IS
RATHER WELL TIED TO THE EXIT CONVERGENT REGION OF A 30KT
SOUTHWESTERLY LOW LEVEL JET...WHICH SHOULD GRADUALLY WEAKEN AND
FOCUS FARTHER NORTH AS THE DAY WEARS ON. AS STATED IN EARLIER
DISCUSSION...WILL DEFER TO DAY SHIFT TO CLEAN UP LINGERING POPS
FROM THIS MORNING...AND POTENTIALLY REMOVE THE SLIGHT POP FROM THE
FAR NORTHERN CWA FOR THE AFTERNOON HOURS. INTERESTINGLY...THE
LATEST HRRR REFLECTIVITY PROG HINTS AT A FEW STORMS FLARING UP
LATE THIS AFTERNOON IN THE WESTERN CWA...WHICH IS ALSO SUPPORTED
BY THE 00Z 4KM WRF-NMM...BUT AT THIS POINT AM NOT FULLY BUYING
INTO IT AS THE PRIMARY LOW LEVEL CONVERGENCE ZONE SHOULD BE
FOCUSED NORTH OF THE AREA BY THEN.
PREV DISCUSSION... /ISSUED 541 AM CDT THU JUL 5 2012/
AVIATION...12Z KGRI TAF...VFR CONDITIONS ARE EXPECTED TO CONTINUE
AT KGRI FOR THE NEXT 24 HOURS. EXPECT A FEW -SHRAS TO SKIRT THE
TERMINAL THROUGH THE EARLY MORNING HOURS...WITH BOTH CIGS AND
VSBYS EXPECTED TO REMAIN VFR THROUGHOUT. SOUTHERLY WINDS NEAR
10KTS THIS MORNING WILL INCREASE TO NEAR 18KTS BY 17Z...WITH ONLY
A FEW-SCT MID/HIGH LEVEL CLOUDS EXPECTED THROUGH THE AFTERNOON
HOURS.
PREV DISCUSSION... /ISSUED 450 AM CDT THU JUL 5 2012/
SHORT TERM...THROUGH SATURDAY NIGHT. FOR THE NEXT FEW
DAYS...CONCERNS REMAIN PRETTY MUCH THE SAME...AND CENTERED AROUND
HEAT AND FIRE WEATHER. HOWEVER...THE BEGINNING STAGES OF A NOTABLE
RETURN TO COOLER TEMPERATURES WILL GET UNDERWAY BY SATURDAY...WITH
AT LEAST SLIGHT THUNDERSTORM CHANCES IN THE MIX AS EARLY AS
SATURDAY NIGHT. FOR FIRE WEATHER INFO...PLEASE REFER TO THE
SEPARATE SECTION BELOW.
08Z OBJECTIVE SURFACE ANALYSIS REVEALS A TROUGH AXIS/WEAK COLD
FRONT STRETCHED FROM EASTERN CO ACROSS WESTERN/NORTH CENTRAL NEB
INTO SOUTHEAST SD. WITH THE CWA POSITIONED JUST EAST OF THIS
FEATURE...MOST AREAS ARE EXPERIENCING SOUTHERLY BREEZES AROUND 10
MPH...WITH SOME HIGHER GUSTS ESPECIALLY IN KS ZONES. THE
COMBINATION OF BREEZES AND HIGH LEVEL CLOUD COVER IS KEEPING PRE-
DAWN TEMPERATURES WELL UP BETWEEN 73-80 MOST AREAS. AS WAS PRETTY
MUCH EXPECTED 24 HOURS AGO...A NARROW AXIS OF THUNDERSTORMS FLARED
UP DURING THE AFTERNOON/EVENING ALONG THE SURFACE
BOUNDARY...PRIMARILY JUST NORTHWEST OF THE CWA BUT AT LEAST
CLIPPING FAR WESTERN DAWSON COUNTY. EVEN AT THIS HOUR...THIS
FAIRLY WEAK STORM CLUSTER PERSISTS ACROSS SEVERAL SOUTHWEST NEB
COUNTIES...BUT SAFELY OUTSIDE THE CWA. ALOFT...EARLY MORNING WATER
VAPOR IMAGERY AND SHORT TERM MODEL DATA PLACE THE HEART OF THE
EXPANSIVE CENTRAL CONUS MID LEVEL RIDGE AXIS OVER MO...WITH WEAK
SHORTWAVE ENERGY RIDING AROUND THE NORTHWEST PERIPHERY OF THE
RIDGE...ALONG WITH SUPPORT FROM A FAIRLY IMPRESSIVE 40+KT 850MB
LOW LEVEL JET AXIS TEAMING UP TO KEEP THE ONGOING SOUTHWEST NEB
STORMS GOING.
STARTING WITH THE FIRST FEW HOURS EARLY THIS MORNING...MADE A
LAST MINUTE DECISION REGARDING POPS...AS LATEST RADAR TRENDS LEND
LITTLE EVIDENCE OF WIDESPREAD CONVECTION PUSHING BACK EAST-
NORTHEAST TOWARD THE CWA...WHICH IS SOMEWHAT CONTRADICTORY TO THE
QPF/REFLECTIVITY PROGS FROM MODELS SUCH AS THE 06Z NAM AND 05Z
HRRR...WHICH STILL SHOW STORMS POTENTIALLY CLIPPING PARTS OF THE
NORTHERN CWA AS THE LOW LEVEL JET CONVERGENCE ZONE AND THE SURFACE
BOUNDARY START TO LIFT BACK TO THE NORTH. ADDING TO THE
DILEMMA...AS I TYPE THIS...BRAND NEW ISOLATED SHOWER/STORM
DEVELOPMENT IS TAKING PLACE NEAR THE HIGHWAY 6/I-80 CORRIDORS
WITHIN THE LOW LEVEL JET AXIS...WHICH COULD REQUIRE AN EXPANSION
OF AT LEAST SLIGHT CHANCE POPS FOR MORE OF MAINLY THE NORTHERN 1/2
OF THE CWA THAN EARLIER EXPECTED. NO MATTER WHAT...MORNING
CONVECTION SHOULD REMAIN FAIRLY SPARSE IN COVERAGE...AND STRONG TO
SEVERE STORMS SHOULD NOT BE AN ISSUE. HEADING INTO THE AFTERNOON
HOURS...THE ONE WILD CARD FROM THE ONGOING MORNING CONVECTION IS
HOW MUCH...IF EVEN AT ALL...IT SLOWS THE NORTHWARD PROGRESSION OF
THE EFFECTIVE SURFACE WARM FRONT. ALTHOUGH THE SOUTHERN HALF OF
THE CWA SHOULD HAVE NO TROUBLE KEEPING PREVAILING SOUTHERLY
BREEZES...NORTHERN AREAS MAY TEND TO STAY A BIT MORE EAST-
SOUTHEASTERLY FOR A PORTION OF THE DAY. WAS VERY TEMPTED TO PULL
OUT THE SLIGHT CHANCE POP ACROSS THE FAR NORTH DURING THE
AFTERNOON...AS CONSENSUS OF VARIOUS MODELS FOCUSES AFTERNOON
CONVECTION CLOSER TO THE NEB/SD BORDER. HOWEVER...WITH THE LIFTING
BOUNDARY STILL SO CLOSE BY...AND FAIRLY WEAK CAPPING AS DEEP
MIXING COMMENCES...WILL LIKELY PLAY IT SAFE AND LET DAY SHIFT
DECIDE LATER THIS MORNING IF ITS SAFE TO FULLY PULL STORM MENTION
FROM THE FAR NORTHERN CWA. EVEN IF AFTERNOON STORMS WOULD CLIP THE
NORTH...NOT EXPECTING SEVERE IN SUCH A CONTINUED WEAK SHEAR
REGIME...ALTHOUGH SMALL HAIL AND GUSTY WINDS OF 50+ MPH CANNOT BE
RULED OUT. TURNING TO TEMPERATURES...OTHER THAN POSSIBLE
COMPLICATING EFFECTS OF CONVECTIVE OUTFLOW SLOWING THE WARM SURGE
IN NORTHERN COUNTIES...SEE NO REASON TO BELIEVE WHY TEMPS TODAY
SHOULDN/T BE ALMOST IDENTICAL TO THOSE OF YESTERDAY GIVEN VERY
LITTLE CHANGE IN THE LOWER LEVEL THERMAL PROFILE. THUS THE HIGH
TEMP GRID IS ESSENTIALLY A COPY-PASTE FROM YESTERDAY...WITH MOST
OF THE CWA INTO THE 100-105 RANGE...EXCEPT FOR UPPER 90S IN
NORTHEAST ZONES SUCH AS POLK/YORK WHERE DEWPOINTS SHOULD HOLD
HIGHER. ALSO LIKE YESTERDAY...HEAT INDEX VALUES SHOULD EASILY
REACH THE 103-105 RANGE IN MANY AREAS...AND LOCALLY HIGHER
ESPECIALLY IN THE CENTRAL/NORTHEAST. AS A RESULT...AND IN ORDER TO
BETTER COLLABORATE WITH PREVIOUSLY ISSUED HEADLINES BY OAX AND LBF
OFFICES...HAVE GONE AHEAD AND ISSUED A CWA-WIDE HEAT ADVISORY NOT
ONLY FOR THIS AFTERNOON BUT ALSO LASTING THROUGH FRIDAY.
FOR TONIGHT...KEPT OUT ALL STORM MENTION...AS THE SURFACE BOUNDARY
AND ALSO LOW LEVEL JET CONVERGENCE SHOULD FOCUS WELL TO THE NORTH
BY THEN...KEEPING THE BEST STORM CHANCES CLOSER TO THE SD BORDER
AND POINTS NORTH. MADE LITTLE CHANGE TO OVERNIGHT LOW TEMPS...WITH
MOST AREAS BETWEEN 72-76...BUT THIS COULD EASILY BE A FEW DEGREES
TOO COOL IN SOME AREAS.
FOR FRIDAY...AS ALREADY MENTIONED...CONTINUED THE HEAT ADVISORY
GOING THROUGH THE AFTERNOON AND EARLY EVENING...AS ONCE AGAIN JUST
SEE LITTLE REASON TO BELIEVE THAT TEMPERATURES WON/T BE AT LEAST
AS HOT AS YESTERDAY/TODAY. IN FACT...WITH THE NAM SUGGESTING THAT
WINDS WILL TAKE ON MORE OF A SOUTHWESTERLY COMPONENT AHEAD OF AN
APPROACHING COLD FRONT...ACTUAL AIR TEMPERATURES FRIDAY COULD BE
EVEN HOTTER THAN CURRENTLY ADVERTISED. TAKING THE MODEL AT FACE
VALUE...EVEN SEVERAL NEBRASKA COUNTIES COULD MAKE A RUN AT OR
EXCEED 105 DEGREES...WITH 105-108 COMMON IN KANSAS. OF
COURSE...THESE VERY HOT READINGS WOULD ALSO DEPEND ON A MIXING OUT
OF DEWPOINTS DURING THE DAY INTO THE 50S-LOWER 60S. ALTHOUGH AM
NOT GOING FULL BORE WITH THE NAM SOLUTION YET...DID BUMP UP HIGHS
FRIDAY 1-3 DEGREES FROM PREVIOUS FORECAST IN MOST AREAS...WITH THE
MAJORITY OF THE CWA AT LEAST INTO THE 100-104 RANGE. AS FOR STORM
CHANCES...LEFT THE ENTIRE DAY AND EVENING DRY...ALTHOUGH THE
LATEST 06 NAM IS NOW BECOMING MORE SUGGESTIVE THAN PREVIOUS RUNS
OF CONVECTION FIRING ALONG A WELL-DEFINED COLD FRONT NEAR THE
NORTHWEST EDGE OF THE CWA LATE IN THE AFTERNOON/EVENING...SIMILAR
TO WHAT JUST HAPPENED WEDNESDAY. HOWEVER...THE NAM SEEMS TO BE A
BIT OF A FAST OUTLIER ON THE SPEED OF THE INVADING BOUNDARY...WITH
THE ECMWF HANGING CONVECTION MOSTLY JUST OFF TO THE
NORTH/NORTHWEST. WILL HAVE TO KEEP AN EYE ON THIS THOUGH. IF
STORMS ARE ABLE TO FORM IN THE NORTHWEST...A FEW STRONG TO
MARGINALLY SEVERE CELLS CANNOT BE RULED OUT...OWING TO SLIGHTLY
STRONGER FORCING AND DEEP LAYER SHEAR CLIMBING CLOSER TO 30KT.
WILL HOLD OFF FOR NOW ON INTRODUCING ANY STORM MENTION FOR FRIDAY
AFTERNOON/NIGHT...BUT THIS COULD BE INTRODUCED DURING THE NEXT FEW
FORECAST CYCLES IF TRENDS HOLD. WHETHER STORMS FORM OR
NOT...CONFIDENCE IS FAIRLY HIGH THAT THE FIRST LEGITIMATE SUMMER
COLD FRONT IN AWHILE WILL MAKE STEADY PROGRESS INTO THE CWA FRIDAY
NIGHT.
SATURDAY...EVEN THE SLOWER ECMWF SOLUTION BRINGS A COLD FRONT AT
LEAST HALFWAY THROUGH THE CWA...WITH BOTH THE NAM/GFS SUGGESTING
IT WILL MAKE IT ALL THE WAY THROUGH THE CWA INTO CENTRAL
KANSAS...WITH NORTHEAST WINDS CWA-WIDE IN ITS WAKE. OBVIOUSLY THE
SPEED/STRENGTH OF THIS FRONTAL INVASION WILL HAVE A BIG IMPACT ON
HIGH TEMPS...AND CONFIDENCE IS A BIT LOWER THAN USUAL FOR ONLY
BEING A FEW DAYS AWAY...WITH ABOUT A 10 DEGREE SPREAD BETWEEN
MODEL SOLUTIONS. TAKING A CONSENSUS APPROACH...NUDGED DOWN
PREVIOUS FORECAST HIGHS 2-3 DEGREES MOST AREAS...NOW CALLING FOR
HIGHS RANGING FROM ONLY UPPER 80S-LOW 90S IN NEB ZONES...AND MID-
UPPER 90S IN KS. IF THIS PANS OUT...WE SHOULD BE OFFICIALLY DONE
WITH THE PROLONGED ROUGHLY 10-DAY STRETCH OF WELL ABOVE NORMAL
HEAT. ALTHOUGH HAVE CONTINUED TO KEEP THE FORECAST DRY FOR
SATURDAY...POPS MAY EVENTUALLY NEED ADDED HERE AS
WELL...ESPECIALLY IF THE FRONT DOES NOT PASS ALL THE WAY SOUTH OF
THE CWA BY THE AFTERNOON HOURS AS THE NAM SUGGESTS.
BY SATURDAY NIGHT...THE TRANSITION TO A MORE NORTHWESTERLY FLOW
REGIME REALLY STARTS TO SHOW ITS HAND...AS THE CENTER OF THE MID-
UPPER RIDGE AXIS RETROGRADES WEST TO OVER THE ROCKIES VERSUS THE
CURRENT CENTRAL/EASTERN PLAINS POSITION. ALTHOUGH CONFIDENCE IN
THE DETAILS IS LOW...VARIOUS MODELS SUGGEST STORMS COULD IMPACT
PARTS OF THE CWA SAT NIGHT...AND HAVE RE-INTRODUCED A SLIGHT POP
ACROSS MAINLY THE SOUTHWEST 2/3 OF THE CWA FOR NOW.
LONG TERM...STARTING 12Z SUNDAY...THE UPPER LEVEL RIDGE IS
ANTICIPATED TO AMPLIFY OVER THE INTERMOUNTAIN WEST EARLY NEXT WEEK
AS A TROUGH OF LOW PRESSURE DIGS ACROSS THE NORTHEAST. THIS WILL
RESULT IN A GENERALLY NORTHWESTERLY FLOW PATTERN ALOFT ACROSS THE
NORTHERN AND CENTRAL PLAINS FOR SEVERAL DAYS...UNTIL LATE IN THE
PERIOD...WHEN THE RIDGE OVER THE INTERMOUNTAIN WEST BEGINS TO SHIFT
FURTHER EASTWARD.
IN THE LOW LEVELS OF THE ATMOSPHERE...EXPECT THE COLD FRONT THAT IS
FORECAST TO REACH THE LOCAL AREA ON SATURDAY...TO LINGER NEAR THE
KS/NE STATE LINES ON SUNDAY...EVENTUALLY PUSHING SOUTH OF THE LOCAL
AREA BY SUNDAY AFTERNOON OR MONDAY. BOTH EC AND GFS TRACK THIS FRONT
ACROSS THE LOCAL AREA AND TO THE SOUTH BY LATE SUNDAY EVENING/EARLY
MONDAY MORNING...AND DUE TO THIS SLIGHT VARIATION IN
TIMING...DECIDED TO KEEP SOME SMALL MENTION OF POPS INTO THE DAY
MONDAY...WITH SKIES THEN CLEARING AND DRY WEATHER EXPECTED
THEREAFTER.
WHILE THERE WILL BE A CHANCE FOR SOME MUCH NEEDED PRECIPITATION WITH
THIS PASSING BOUNDARY...INSTABILITY AND SHEAR BOTH APPEAR VERY
MARGINAL...AND WIDESPREAD SEVERE WEATHER IS NOT ANTICIPATED AT THIS
TIME. AT THIS POINT...IT APPEARS COOLING TEMPERATURES WILL BE AS
WELCOME AS RAIN CHANCES OVER THE UPCOMING WEEKEND...WITH 850 MB
TEMPS FORECAST TO DROP AS MUCH AS 10C DEPENDING ON WHICH MODEL YOU
ARE LOOKING AT. WITH COOLER TEMPS ALOFT...SOME ANTICIPATED CLOUDS
AND AT LEAST SPOTTY RAINFALL...WENT AHEAD AND LOWERED TEMPS SUNDAY
AFTERNOON BELOW SEASONAL NORMS FOR THE FIRST TIME IN A WHILE...WITH
CONTINUED SEASONABLY COOL WEATHER THEN ANTICIPATED THROUGH THE END
OF NEXT WEEK. BESIDES LOWERING TEMPS A BIT ON SUNDAY AND TRIMMING
POPS A SMALL AMOUNT MONDAY AFTERNOON...NO OTHER SIGNIFICANT CHANGES
NECESSARY TO BLENDED MODEL SOLUTIONS THIS MORNING.
FIRE WEATHER...ALTHOUGH THE COMBINATION OF RELATIVE HUMIDITY
DROPPING TO AROUND 20 PERCENT AND SUSTAINED WINDS NEAR 20
MPH/GUSTS AROUND 25 MPH WILL AGAIN PROMOTE AT LEAST NEAR-CRITICAL
FIRE DANGER ACROSS SEVERAL SOUTHERN COUNTIES THIS
AFTERNOON...OPTED TO HOLD OFF ON A FORMAL RED FLAG WARNING THIS
TIME AROUND...AS CONDITIONS SHOULD BE VERY SIMILAR TO
YESTERDAY...DURING WHICH RED FLAG CRITERIA STRUGGLED TO
MATERIALIZE FOR 3 OR MORE HOURS. HOWEVER...IT COULD STILL BE A
CLOSE CALL...AND SOMETHING THAT DAY SHIFT WILL HAVE TO MONITOR.
DESPITE THE LACK OF A FORMAL RED FLAG WARNING AT THIS
TIME...EXTREME FIRE DANGER WILL BE HIGHLIGHTED FOR SEVERAL
COUNTIES IN THE GRASSLAND FIRE DANGER PRODUCT...AND WILL CONTINUE
TO MENTION IN THE HAZARDOUS WEATHER OUTLOOK. TURNING TO
FRIDAY...THERE MIGHT ACTUALLY BE GREATER FIRE CONCERNS ON THIS
DAY...AS WINDS TURN MORE SOUTHWESTERLY AND SPREAD SUB-20 PERCENT
RH POTENTIAL FARTHER NORTHEAST...POTENTIALLY INTO ALL AREAS
SOUTHWEST OF A LEXINGTON-BELOIT LINE. IT APPEARS THE LIMITING
FACTOR FOR EVENTUAL RED FLAG ISSUANCE COULD BE WIND SPEEDS...AS
CURRENTLY HAVE SUSTAINED SPEEDS AVERAGING CLOSER TO 15 MPH VERSUS
20 MPH. IF WINDS WERE EXPECTED TO BE ROUGHLY 5 MPH HIGHER...WOULD
HAVE CONSIDERED ISSUING A FIRE WEATHER WATCH...AND DAY SHIFT WILL
HAVE TO TAKE ANOTHER LOOK TO SEE IF AT LEAST A WATCH MIGHT BE
WARRANTED FOR FRIDAY. FORTUNATELY...THE INVASION OF A COOLER
AIRMASS FOR SATURDAY AND THE NEXT SEVERAL DAYS THEREAFTER SHOULD
AT LEAST EASE UP THE UNSEASONABLY HIGH FIRE DANGER WE HAVE HAD
LATELY.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...HEAT ADVISORY UNTIL 9 PM CDT FRIDAY FOR NEZ039>041-046>049-
060>064-072>077-082>087.
KS...HEAT ADVISORY UNTIL 9 PM CDT FRIDAY FOR KSZ005>007-017>019.
&&
$$
SECOND UPDATE...HEINLEIN
FIRST UPDATE/SHORT TERM/FIRE WEATHER...PFANNKUCH
LONG TERM/AVIATION...ROSSI
AREA FORECAST DISCUSSION
NWS RALEIGH NC
331 PM EDT THU JUL 5 2012
.SYNOPSIS...
AN UPPER LEVEL RIDGE EXTENDING EASTWARD FROM THE CENTRAL MISSISSIPPI
RIVER VALLEY TOWARD THE CAROLINAS WILL RESULT IN ABOVE NORMAL
TEMPERATURES THROUGH THE UPCOMING WEEKEND...WITH A CHANCE FOR
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON
AND EVENING HOURS EACH DAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1130 AM THURSDAY...
OVERVIEW:
NORTHWEST FLOW ALOFT WILL PREVAIL OVER THE CAROLINAS THROUGH
TONIGHT...ON THE EASTERN PERIPHERY OF AN UPPER LEVEL RIDGE CENTERED
OVER THE CENTRAL MS RIVER VALLEY. 14Z WV IMAGERY AND RUC DATA
INDICATED MULTIPLE MID/UPPER LEVEL DISTURBANCES EMBEDDED WITHIN NW
FLOW ALOFT OVER THE MID-ATLANTIC AND CAROLINAS.
TEMPERATURES:
THE 12Z GSO RAOB INDICATED A 1000-850 MB THICKNESS OF 1434 METERS
THIS MORNING. THIS IS CONSISTENT WITH THE LATEST MODEL GUIDANCE...
WHICH CONTINUES TO INDICATE 1000-850 MB THICKNESSES IN VICINITY OF
1455 METERS BY 00Z...ROUGHLY 10-15 METERS HIGHER THAN YESTERDAY.
MODEL GUIDANCE INDICATES H85 TEMPS IN THE 21-23C RANGE THIS
AFTERNOON...GENERALLY CONSISTENT WITH UPSTREAM CONDITIONS PER 14Z
SPC MESOANALYSIS (THOUGH COOLER TEMPS ARE PRESENT OVER WV IN ASSOC/W
MCS REMNANTS). HIGHS YESTERDAY RANGED FROM 95-98F IN MOST
LOCATIONS...RDU AN EXCEPTION AT 101F. BASED ON YESTERDAY`S TEMPS AND
A 10-15 METER INCREASE IN THICKNESSES...EXPECT HIGHS IN VICINITY OF
100F TODAY...THOUGH ISOLD/SCT CONVECTION MAY PREVENT HIGHS FROM
EXCEEDING THE MID/UPPER 90S IN SOME LOCATIONS. DECIDED TO INCREASE
THE HIGH AT RDU TO 102F BASED ON YESTERDAY`S READING. WILL DECREASE
HIGHS A FEW DEGREES LOWER THAN WHAT THICKNESSES SUGGEST IN THE FAR
NW PIEDMONT WHERE OUTFLOW FROM MCS REMNANTS (AND NEWLY DEVELOPED
CONVECTION NEAR BLUEFIELD WV) MAY AFFECT TEMPS BY EARLY/MID
AFTERNOON. H85 DEWPOINTS RANGED FROM 13-15C (55-60F) ACROSS THE AREA
AT 14Z...AND SHOULD REMAIN IN THAT VICINITY THROUGH THE AFTERNOON.
GIVEN STRONG HEATING AND MIXING UP TO AT LEAST H85...ANTICIPATE THAT
DEWPOINTS WILL MIX OUT INTO THE LOWER/MID 60S IN THE NORTHERN AND
WESTERN PIEDMONT. IN THE SANDHILLS AND COASTAL PLAIN ON THE EASTERN
PERIPHERY OF THE LEE TROUGH...EXPECT DEWPOINTS WILL LIKELY REMAIN IN
THE UPPER 60S TO LOWER 70S GIVEN RELATIVELY HIGHER H85 DEWPOINTS IN
THE PRESENCE OF SHALLOW LOW-LEVEL CONVERGENCE AND MOISTURE POOLING.
EXPECT OVERNIGHT LOWS A BIT WARMER THAN THIS MORNING DUE TO AIRMASS
MODIFICATION...IN THE LOWER/MID 70S...OR 72-75F.
HEAT INDICES/HEAT ADVISORY:
WITH THE ABOVE T/TD DISCUSSION IN MIND...ANTICIPATE MAX HEAT INDICES
BETWEEN 105-110F IN THE ADVISORY AREA...WITH HEAT INDICES
APPROACHING 105F IN THE TRIANGLE...AND GENERALLY 100-105F IN THE
WESTERN PIEDMONT. DESPITE MAX HEAT INDICES FORECAST NEAR 105F IN
WAKE/FRANKLIN/WARREN COUNTIES...DECIDED NOT TO EXPAND THE HEAT
ADVISORY TO INCLUDE THOSE COUNTIES GIVEN A FAIR AMOUNT OF
UNCERTAINTY W/REGARD TO DEWPOINTS ALONG/WEST OF HWY 1 AND CONVECTIVE
EVOLUTION MID/LATE AFTERNOON.
PRECIPITATION CHANCES:
MID-LEVEL LAPSE RATES ARE SEASONABLY STEEP TODAY ACCORDING TO 15Z
SPC MESOANALYSIS DATA...IN VICINITY OF 6.5 C/KM. GIVEN SURFACE TEMPS
EASILY IN THE MID/UPPER 90S AND DEWPOINTS RANGING FROM THE LOWER/MID
60S TO NEAR 70F (IN ANTICIPATION OF SOME MIX-DOWN BY 18-21Z)...
EXPECT MLCAPE VALUES SOLIDLY IN THE MODERATE RANGE...PERHAPS
STRONG...GENERALLY BETWEEN 1500-2500 J/KG. W/REGARD TO FORCING... A
COMPLEX NW FLOW ALOFT PATTERN IS PRESENT OVER CENTRAL NC...WITH AT
LEAST SEVERAL IMPORTANT FEATURES. 1) A SHORTWAVE IN VICINITY OF CAPE
FEAR IS PROGGED TO TRACK SOUTHWARD INTO EASTERN SC/OFFSHORE AS THE
AFTERNOON PROGRESSES...AND SUBSIDENCE IN THE WAKE OF THIS FEATURE
MAY INITIALLY SUPPRESS DEVELOPMENT OVER THE COASTAL PLAIN...
ESPECIALLY IN THE SE COASTAL PLAIN. 2) THE REMNANTS OF AN MCS OVER
NORTHERN VA AT 03Z HAVE PROGRESSED INTO CENTRAL NC EARLY THIS
AFTERNOON. HOWEVER...FORCING ASSOC/W THIS FEATURE IS DIFFICULT TO
ASCERTAIN. 3) THE REMNANTS OF AN MCS OVER OHIO AT 03Z HAVE
PROGRESSED INTO SOUTHWEST VA BY 17Z THIS AFTERNOON...ALREADY FORCING
CONVECTION ALONG THE I-77 CORRIDOR IN NORTHWEST NC. 4) AN ONGOING
MCS IN WV AT 17Z...THOUGH EXPECTED TO TRACK INTO THE FAR WESTERN
PORTIONS OF THE STATE. ADDITIONALLY...A SURFACE TROUGH AXIS IN
VICINITY OF THE HWY 1 CORRIDOR WILL PROVIDE A LOW-LEVEL FOCUS FOR
CONVECTION THIS AFT/EVE. WITH THE ABOVE IN MIND...WILL INDICATE
PRECIP CHANCES 30-40% IN THE FAR WESTERN PIEDMONT...AND 20-30% IN
VICINITY OF THE HWY 1 CORRIDOR...AND ~20% IN THE CENTRAL/SE COASTAL
PLAIN.
SEVERE THREAT:
MLCAPE SOLIDLY IN THE MODERATE RANGE WILL RESULT IN ROBUST UPDRAFTS
TODAY...THOUGH DEEP-LAYER SHEAR WILL BE NO MORE THAN 15-20 KT.
HOWEVER...DUE TO LARGE T/TD SPREADS AND VERY HIGH DCAPE VALUES
ANALYZED PER LATEST SPC MESOANALYSIS (1000-1600 J/KG...HIGHEST
WEST)...EXPECT MULTICELL ORGANIZATION PRIMARILY ALONG OUTFLOW.
THOUGH HAIL UP TO THE SIZE OF QUARTERS WILL BE POSSIBLE GIVEN
MODERATE INSTABILITY...THE PRIMARY THREAT WILL BE ASSOCIATED WITH
DAMAGING WINDS OWING TO VERY HIGH DCAPE VALUES/STRONG BOUNDARY LAYER
EVAPORATIVE COOLING POTENTIAL. THE THREAT FOR SEVERE WEATHER WILL BE
HIGHEST IN THE WESTERN PIEDMONT (WHERE THE SLIGHT RISK IS INDICATED
ON THE DAY 1 OUTLOOK) BETWEEN 1 PM THIS AFTERNOON AND 8-11 PM THIS
EVENING. THIS IS WHERE THE HIGHEST DCAPE VALUES ARE PRESENT AND
WHERE THE RELATIVE BEST MID LEVEL FORCING IS EXPECTED AS REMNANT MCS
ACTIVITY PROGRESSES SOUTH/SSW INTO WESTERN PORTIONS OF THE STATE.
ISOLATED SEVERE WEATHER WILL BE POSSIBLE ELSEWHERE CONVECTION IS
PRESENT OWING TO 1000+ J/KG OF DCAPE/STEEP LOW-LEVEL LAPSE RATES IN
THE PRESENCE OF MODERATE INSTABILITY. -VINCENT
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 220 PM THURSDAY...
THE MID LEVEL RIDGE CURRENTLY CENTERED TO OUR WEST OVER THE CENTRAL
PLAINS WILL EXPAND EASTWARD AS THE TROUGH OFF THE NEW ENGLAND COAST
MOVES EAST. AT THE SFC AND LOWER LEVELS...NOT MUCH WILL CHANGE WITH
THE LEE TROUGH REMAINING IN PLACE. LOW LEVEL THICKNESSES ARE PROGGED
TO REMAIN THE SAME...THUS EXPECT HIGHS TOMORROW VERY SIMILAR TO
TODAYS VALUES...AROUND 100 ACROSS MUCH OF OUR CWA. GUIDANCE IS IN
GOOD AGREEMENT THAT DWPTS WILL BE LOWER ACROSS OUR WESTERN ZONES
(UPPER 60S WEST TO LOWER 70S EAST)...THUS HEAT INDEX VALUES WILL
RANGE FROM 100-103 WEST TO 104-107 EAST. THE HEAT ADVISORY THAT IS
ALREADY IN EFFECT FROM 11 AM TO 8 PM FRIDAY LOOKS GOOD AND WILL
LEAVE AS-IS. AS FOR TSTM POTENTIAL ON FRIDAY...NOTED SUBTLE
MID-LEVEL WARMING IN FORECAST SOUNDINGS BUT STILL ENOUGH MOISTURE
AND INSTABILITY/CAPE TO SEE SOME AFTERNOON TSTMS. GFS DEPICTS A WEAK
MID LEVEL SHEAR AXIS MOVING SOUTHEAST ACROSS THE STATE LATE IN THE
DAY. THUS EXPECT ISOLATED TO SCATTERED TSTMS...WITH PERHAPS THE
BETTER CHANCE FOR TSTMS ACTIVITY AND STRONGER INTENSITY WILL BE
ACROSS OUR EASTERN PIEDMONT AND COASTAL PLAIN ZONES WHERE FORECAST
SOUNDINGS AND SFC DWPT PROGS SUGGEST BETTER CAPE. ANY ACTIVITY WILL
WIND DOWN DURING THE LATE EVENING WITH PC CONDITIONS AT NIGHT. LOWS
FRI NIGHT IN THE LOW-MID 70S.
ON SATURDAY THE MID LEVEL RIDGE WILL BUILD OVER TOP OF CENTRAL NC...
WITH CONTINUED MID LEVEL WARMING. WITH 850 MB TEMPS WARMING AND LOW
LEVEL THICKNESSES INCREASING...EXPECT ANOTHER HOT DAY WITH HIGHS
ONCE AGAIN AROUND 100. HEAT ADVISORIES MAY ONCE AGAIN BE NEEDED.
WITH THE AFOREMENTIONED MID LEVEL WARMING AND WEAKENING LAPSE
RATES...TSTM COVERAGE SHOULD BE FURTHER REDUCED. BEST CHANCE WILL
CONTINUE TO BE ACROSS OUR EASTERN ZONES WHERE HIGHER PW AND DWPTS
ARE LOCATED. LITTLE CHANGE SATURDAY NIGHT...LOWS IN THE MID 70S.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 220 PM THURSDAY...
ON SUNDAY THE MID LEVEL RIDGE WILL MOVE EAST AS A POTENT SHORT WAVE
MOVES SE ACROSS THE GREAT LAKES. A COLD FRONT WILL BE MOVING ACROSS
THE OH RIVER VALLEY. SUNDAY SHOULD BE THE LAST HOT DAY IN THE
FORECAST PERIOD WITH LITTLE OR NO AIRMASS CHANGE FROM PREVIOUS DAYS.
EXPECT HIGHS ONCE AGAIN AROUND 100. WITH MID LEVELS BEGINNING TO
COOL AND PWAT INCREASING AHEAD OF THE TROUGH...WILL CONTINUE WITH
ISOLD TO SCATTERED AFTERNOON AND EVENING TSTMS.
MONDAY WILL BE A TRANSITION DAY AS THE LONGWAVE TROUGH DEEPENS
ACROSS THE EASTERN HALF OF THE COUNTRY AND THE ASSOC COLD FRONT
STALLS ACROSS THE CAROLINAS. THIS PATTERN WILL THEN REMAIN WITH US
THROUGH MUCH OF THE WEEK...RESULTING IN AT LEAST A GOOD CHANCE FOR
SHOWERS AND TSTMS EACH DAY AND NEAR SEASONABLE TEMPS.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 230 PM THURSDAY...
24-HR TAF PERIOD:
ASIDE FROM SCATTERED SHOWERS AND STORMS CAPABLE OF PRODUCING SURFACE
WIND GUSTS TO ~50 KT BETWEEN ROUGHLY 18Z THIS AFTERNOON AND 00Z THIS
EVENING...EXPECT VFR CONDITIONS THROUGH THE REMAINDER OF THE TAF
PERIOD.
LOOKING AHEAD:
ABOVE NORMAL TEMPERATURES WITH PRIMARILY AFTERNOON/EVENING CHANCES
FOR SHOWERS AND THUNDERSTORMS ARE EXPECTED FRIDAY INTO THE WEEKEND
IN ASSOCIATION WITH N/NW FLOW ALOFT ON THE EASTERN PERIPHERY OF AN
UPPER LEVEL RIDGE OVER THE CENTRAL CONUS. OTHERWISE...ANTICIPATE VFR
CONDITIONS TO PREDOMINATE. -VINCENT
&&
.CLIMATE...
HIGH TEMPERATURE RECORDS AND YEAR RECORD LAST SET.
RALEIGH-DURHAM... GREENSBORO...
07/05 102 1999 98 1990
07/06 102 1999 100 1977
07/07 102 2010 101 1977
07/08 103 1977 102 1977
FAYETTEVILLE...
07/05 101 2002
07/06 99 1990
07/07 103 2010
07/08 102 1977
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY FROM 11 AM THIS MORNING TO 9 PM EDT THIS EVENING
FOR NCZ011-027-028-042-043-077-078-085-086-088-089.
HEAT ADVISORY FROM 11 AM TO 8 PM EDT FRIDAY FOR NCZ008>011-
025>028-040>043-074>078-083>086-088-089.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT
SHORT TERM...NP
LONG TERM...NP
AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
324 PM EDT THU JUL 5 2012
.SYNOPSIS...
BERMUDA HIGH PRESSURE OFFSHORE AND THE PIEDMONT TROUGH INLAND WILL
PREVAIL THROUGH MUCH OF THE FORECAST PERIOD...BRINGING HOT AND HUMID
CONDITIONS WITH ISOLATED THUNDERSTORMS EACH AFTERNOON AND EVENING.
AN UPPER RIDGE OVER THE AREA WILL SLOWLY WEAKEN NEXT WEEK...BRINGING
DAYTIME TEMPERATURES CLOSER TO NORMAL FOR JULY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 130 PM THURSDAY...HEAT ADVISORY CONTINUES WITH HEAT AND
HUMIDITY COMBINING TO PRODUCE HEAT INDEX VALUES UP TO 107 DEGREES.
WITH STRONG UPPER RIDGE TO OUR WEST THE H5 HEIGHTS REMAIN UP
AROUND 590 DEM AND 850 TEMPS WILL BE JUST OVER 20C. THE WESTERLY
LOW LEVEL FLOW ALSO HELPING TO PRODUCE EXCESSIVE HEAT ACROSS AREA
WHILE SW FLOW OF MOIST AIR HELPS TO KEEP DEWPOINT TEMPS UP AROUND
70. THE ACTUAL TEMPS WILL REACH BETWEEN 95 AND 100 THIS AFTERNOON.
THE HEAT INDEX SHOULD HOLD JUST BELOW 105 DEG ALONG A SLIVER OF
COASTAL NORTH CAROLINA DUE TO THE SEA BREEZE CIRCULATION. A HEAT
ADVISORY WILL BE IN EFFECT FOR MOST OF THE AREA UNTIL 9 PM THIS
EVENING.
LOCAL AREA REMAINS ON EASTERN PERIPHERY OF THE STRONG RIDGE TO
THE WEST. THIS WILL ALLOW ANY PERTURBATIONS AND ASSOCIATED ORGANIZED
CONVECTION TOPPING THE RIDGE TO MAKE A RUN FOR THE CAROLINAS. ANOTHER
MORE POTENT PERTURBATION WILL RIDE DOWN FROM THE NORTH THROUGH
TONIGHT BUT MOST OF THE ASSOCIATED ENERGY WILL REMAIN WEST OF
LOCAL AREA WITH COASTAL SECTIONS REMAINING IN SUBSIDENCE THROUGH
MUCH OF THE DAY. THE SEA BREEZE AND PIEDMONT TROUGH WILL PROVIDE
SOME ADDED LOW LEVEL FORCING AND CONVERGENCE...ALLOWING ISOLATED
CONVECTION TO POP WITH STRONG HEATING. THE HRRR SHOWED CONVECTION
FLARING ALONG SEA BREEZE BOUNDARY THROUGH THIS LATE THIS
AFTERNOON. GIVEN THE MID LEVEL DRY AIR AND SUBSIDENCE WILL KEEP
STORMS ISOLATED THROUGH THIS EVENING. THE LOW LEVEL FLOW WILL BACK
TO A MORE NORTHERLY DIRECTION PRODUCING A NORTHERLY STEERING FLOW.
THEREFORE ANY SHOWERS THAT DEVELOP WILL MOVE VERY SLOWLY SOUTH.
LATEST NAM SHOWS SHORTWAVE RIDING DOWN THROUGH WESTERN CAROLINAS
COULD AFFECT MAINLY WESTERN COUNTIES OF LOCAL CWA LATER THIS
EVENING INTO OVERNIGHT HOURS. WILL KEEP SLIGHT CHC POPS IN
FORECAST OVERNIGHT.
TEMPS WILL BE SLOW TO DROP TONIGHT WITH NOCTURNAL SOUTHWEST
JET. NAM WINDS JUST ABOVE THE SURFACE WILL BE UP NEAR 25K KTS.
EXPECT ATMOSPHERE TO DECOUPLE ALLOWING SURFACE WINDS TO DROP BUT
THIS SHOULD HAVE SOME AFFECT ON THE TEMPS OVERNIGHT. OVERALL WARM
AND HUMID AIR MASS IN PLACE WITH TEMPS HOLDING ABOVE 80 THROUGH
MOST OF THE EVENING AND FALLING INTO THE UPPER 70S MOST PLACES BY
DAYBREAK.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 PM THURSDAY...MID/UPPER LEVEL RIDGE OVER THE CENTRAL
CONUS ON FRIDAY WILL FLATTEN AND SPREAD EASTWARD ON SATURDAY...
WITH INCREASING HEIGHTS OVER THE CWA THROUGH THE PERIOD. TIME-
HEIGHT CROSS SECTIONS SHOW A LAYER OF RELATIVELY DRY AIR BETWEEN
700-400 MB...WITH ONLY MODEST MOISTURE BELOW 700 MB. A DEEP LAYER
OF SUBSIDENCE IS ALSO NOTED IN RESPONSE TO THE INCREASING HEIGHTS.
ALTHOUGH DEEP MOISTURE IS LACKING...SURFACE DEWPOINTS IN THE MID
70S COMBINED WITH SB CAPE TO 2500 J/KG AND LI`S TO -6C WILL MAKE IT
TOUGH TO RULE OUT THE CHANCE FOR CONVECTION ALTOGETHER. ISOLATED
DEVELOPMENT WILL BE POSSIBLE FRIDAY AND SATURDAY ALONG THE SEA
BREEZE AND PIEDMONT TROUGH...BUT EXPECT CHANCES TO BE HIGHER
FRIDAY AS A SUBTLE MID-LEVEL SHORTWAVE DROPS SOUTH ACROSS THE
AREA DURING MIDDAY HEATING. ALSO NOTABLE LATE FRIDAY NIGHT AND
THROUGH SATURDAY IS DEEP ONSHORE FLOW ABOVE 700 MB. ANY CONVECTION
THAT DEVELOPS OVER THE WATERS WILL BE STEERED TOWARDS SHORE.
GIVEN WIDESPREAD HIGHS EXPECTED TO BE IN THE MID AND UPPER
90S FRIDAY AND SATURDAY...AND DEWPOINTS IN THE MID 70S...HEAT INDICES
SHOULD REACH 105 AT MANY LOCATIONS. THEREFORE WILL RAISE ANOTHER
HEAT ADVISORY FOR FRIDAY...AND ONE MAY BE REQUIRED FOR SATURDAY ALSO.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 3 PM THURSDAY...SUNDAY SHOULD BE THE LAST DAY OF EXTREME
HEAT. HIGH TEMPERATURES IN THE UPPER 90S AWAY FROM THE COAST COUPLED
WITH MID-70S DEWPOINTS SHOULD AGAIN YIELD HEAT INDICES ABOVE 105
DEGREES DURING THE DAY. THE HOT UPPER LEVEL RIDGE CAUSING THE HEAT
THIS WEEKEND WILL PASS VIRTUALLY OVERHEAD SUNDAY...THEN OFFSHORE
MONDAY. THIS WILL SHIFT THE DEEP-LAYER FLOW AROUND TO THE SOUTH ON
MONDAY... WITH DECREASING 850 MB TEMPS AND 1000-500 MB THICKNESSES
SHOWN ON GFS/ECMWF MODEL PLOTS. MONDAY`S HIGHS SHOULD THEREFORE RUN
A FEW DEGREES COOLER THAN ON SUNDAY. COOLING AND MOISTENING
MID-LEVELS SHOULD FAVOR BETTER A LITTLE CONVECTIVE POTENTIAL MONDAY
AS WELL.
BY TUESDAY THE PATTERN BECOMES EVEN MORE FAVORABLE FOR CONVECTION AS
A SYNOPTIC SURFACE FRONT DROPS SOUTH INTO THE CAROLINAS AND DEEP
MOISTURE INCREASES ALOFT AHEAD OF A DEVELOPING LONGWAVE TROUGH
EXTENDING FROM THE GREAT LAKES DOWN TO THE GULF COAST. GFS AND ECMWF
FORECAST SOUNDINGS SHOW AN UNCAPPED TROPICAL AIRMASS WITH SLIGHTLY
STEEPER THAN MOIST-ADIABATIC LAPSE RATES PERSISTING FOR SEVERAL DAYS
THIS WEEK...WITH PRECIP WATER INCREASING TO NEAR 2.0 INCHES. WE`VE
INCREASED THE AREA OF 40-50 PERCENT 12-HR POPS FORECAST TUESDAY
THROUGH THURSDAY AS THIS PATTERN CERTAINLY SHOULD EXCEED THE
CLIMATOLOGICAL 20-30 PERCENT 12-HR POP FOR THIS TIME OF YEAR.
UNIDIRECTIONAL SOUTH-SOUTHWEST WINDS AND MODEST LAPSE RATES WILL
SUPPORT HEAVY RAINFALL BUT NOT NECESSARILY SEVERE WEATHER.
DIURNAL TEMPERATURE RANGES WILL BECOME CONSTRICTED TUESDAY THROUGH
THURSDAY BY THE ADDITIONAL CLOUDS AND PRECIP...WITH HIGHS AVERAGING
IN THE UPPER 80S. LOWS SHOULD RANGE FROM 70-75.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 18Z...UPPER AIR SOUNDING STILL HAS A WEAK SUBSIDENCE
INVERSION BUT THERE SHOULD BE A BIT LESS CONVECTIVE INHIBITION
TODAY. THE NSSL WRF SHOWS A COMPLEX OF STORMS DROPPING SOUTHEAST
INTO THE REGION THIS AFTERNOON. FEEL THIS MAY BE A BIT
OVERDONE...WENT WITH VCTS IN THE TAFS. COULD NOT RULE OUT A GOOD
THUNDERSTORM...BEST CHANCE AT THE INLAND TERMINALS. CONTINUED
SOUTHWEST FLOW...A BIT GUSTY ALONG THE COAST. TONIGHT...ISOLATED
CONVECTION WILL BE WANING...WITH MID AND HIGH CLOUD DEBRIS. LIGHT
SOUTHWEST FLOW.
EXTENDED OUTLOOK...A CHANCE OF THUNDERSTORMS EACH DAY...MAINLY IN
THE AFTERNOON AND EVENING. OTHERWISE EXPECT VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 130 PM THURSDAY...SOUTHWEST FLOW BETWEEN BERMUDA HIGH AND
PIEDMONT TROUGH OVER INLAND CAROLINAS WILL CONTINUE THROUGH
TONIGHT. NAM CONTINUES TO SHOW NOCTURNAL JET UP TO 25 KTS OVER THE
COASTAL WATERS OVERNIGHT. THE 975 MB WINDS ARE COMING IN CLOSE TO
35 KTS. OVERALL WILL SEE ENHANCED SEA BREEZE FLOW DIMINISH NEAR
SHORE THROUGH THIS EVENING BUT THIS JET ACROSS THE WATERS WILL
KEEP WINDS UP OVERNIGHT. SOUTHWEST WINDS 15 TO 20 KTS WILL KEEP
SEAS AROUND 3 TO 4 FT ACROSS MUCH OF THE WATERS THROUGH TONIGHT
AND COULD SPIKE AS HIGH AS 5 FT IN OUTERMOST WATERS.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 PM THURSDAY...SOUTHWEST FLOW WILL PERSIST OVER THE WATERS
THROUGH THE PERIOD BETWEEN A SURFACE TROUGH LOCATED OVER THE
INLAND CAROLINAS AND BERMUDA HIGH PRESSURE. THE MSLP GRADIENT
MAGNITUDE WILL INCREASE EACH AFTERNOON IN RESPONSE TO THE SEA
BREEZE.
LONG TERM /SUNDAY THROUGH MONDAY/...
AS OF 3 PM THURSDAY...HIGH PRESSURE WELL OFF THE U.S. EAST COAST
SHOULD CONTINUE TO PUMP A WARM AND HUMID AIRMASS ONSHORE THROUGH
EARLY NEXT WEEK. THE PIEDMONT TROUGH SUNDAY WILL BECOME REPLACED ON
MONDAY BY LOW PRESSURE ALONG A COLD FRONT DIPPING SOUTH FROM
VIRGINIA. THIS FRONT SHOULD REMAIN NORTH OF THE COASTAL WATERS...BUT
MAY GET CLOSE ENOUGH TO BRING INCREASING CHANCES OF SHOWERS AND
THUNDERSTORMS MONDAY INTO TUESDAY. OTHERWISE...SOUTHWEST WINDS 10-15
KNOTS MAY INCREASE TO NEAR 20 KNOTS NEARSHORE DURING THE AFTERNOONS
DUE TO THE SEA BREEZE CIRCULATION. SEAS SHOULD AVERAGE 2-4 FT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...HEAT ADVISORY UNTIL 9 PM EDT THIS EVENING FOR SCZ017-023-024-
032-033-039-053>056.
HEAT ADVISORY FROM NOON TO 8 PM EDT FRIDAY FOR SCZ017-023-024-
032-033-039-053>056.
NC...HEAT ADVISORY UNTIL 9 PM EDT THIS EVENING FOR NCZ087-096-099-
105-107-109.
HEAT ADVISORY FROM NOON TO 8 PM EDT FRIDAY FOR NCZ087-096-099-
105>110.
MARINE...NONE.
&&
$$
SYNOPSIS...CRM
NEAR TERM...RGZ
SHORT TERM...CRM
LONG TERM...TRA
AVIATION...RGZ/DL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
232 PM EDT THU JUL 5 2012
.SYNOPSIS...
BERMUDA HIGH PRESSURE OFFSHORE AND THE PIEDMONT TROUGH INLAND WILL
PREVAIL THROUGH MUCH OF THE FORECAST PERIOD...BRINGING HOT AND HUMID
CONDITIONS WITH ISOLATED THUNDERSTORMS EACH AFTERNOON AND EVENING.
AN UPPER RIDGE OVER THE AREA WILL SLOWLY WEAKEN NEXT WEEK...BRINGING
DAYTIME TEMPERATURES CLOSER TO NORMAL FOR JULY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 130 PM THURSDAY...HEAT ADVISORY CONTINUES WITH HEAT AND
HUMIDITY COMBINING TO PRODUCE HEAT INDEX VALUES UP TO 107 DEGREES.
WITH STRONG UPPER RIDGE TO OUR WEST THE H5 HEIGHTS REMAIN UP
AROUND 590 DEM AND 850 TEMPS WILL BE JUST OVER 20C. THE WESTERLY
LOW LEVEL FLOW ALSO HELPING TO PRODUCE EXCESSIVE HEAT ACROSS AREA
WHILE SW FLOW OF MOIST AIR HELPS TO KEEP DEWPOINT TEMPS UP AROUND
70. THE ACTUAL TEMPS WILL REACH BETWEEN 95 AND 100 THIS AFTERNOON.
THE HEAT INDEX SHOULD HOLD JUST BELOW 105 DEG ALONG A SLIVER OF
COASTAL NORTH CAROLINA DUE TO THE SEABREEZE CIRCULATION. A HEAT
ADVISORY WILL BE IN EFFECT FOR MOST OF THE AREA UNTIL 9 PM THIS
EVENING.
LOCAL AREA REMAINS ON EASTERN PERIPHERY OF THE STRONG RIDGE TO
THE WEST. THIS WILL ALLOW ANY PERTURBATIONS AND ASSOCIATED ORGANIZED
CONVECTION TOPPING THE RIDGE TO MAKE A RUN FOR THE CAROLINAS. ANOTHER
MORE POTENT PERTURBATION WILL RIDE DOWN FROM THE NORTH THROUGH
TONIGHT BUT MOST OF THE ASSOCIATED ENERGY WILL REMAIN WEST OF
LOCAL AREA WITH COASTAL SECTIONS REMAINING IN SUBSIDENCE THROUGH
MUCH OF THE DAY. THE SEABREEZE AND PIEDMONT TROUGH WILL PROVIDE
SOME ADDED LOW LEVEL FORCING AND CONVERGENCE...ALLOWING ISOLATED
CONVECTION TO POP WITH STRONG HEATING. THE HRRR SHOWED CONVECTION
FLARING ALONG SEA BREEZE BOUNDARY THROUGH THIS LATE THIS
AFTERNOON. GIVEN THE MID LEVEL DRY AIR AND SUBSIDENCE WILL KEEP
STORMS ISOLATED THROUGH THIS EVENING. THE LOW LEVEL FLOW WILL BACK
TO A MORE NORTHERLY DIRECTION PRODUCING A NORTHERLY STEERING FLOW. THEREFORE
ANY SHOWERS THAT DEVELOP WILL MOVE VERY SLOWLY SOUTH.
LATEST NAM SHOWS SHORTWAVE RIDING DOWN THROUGH WESTERN CAROLINAS
COULD AFFECT MAINLY WESTERN COUNTIES OF LOCAL CWA LATER THIS
EVENING INTO OVERNIGHT HOURS. WILL KEEP SLIGHT CHC POPS IN
FORECAST OVERNIGHT.
TEMPS WILL BE SLOW TO DROP TONIGHT WITH NOCTURNAL SOUTHWEST
JET. NAM WINDS JUST ABOVE THE SURFACE WILL BE UP NEAR 25K KTS.
EXPECT ATMOSPHERE TO DECOUPLE ALLOWING SURFACE WINDS TO DROP BUT
THIS SHOULD HAVE SOME AFFECT ON THE TEMPS OVERNIGHT. OVERALL WARM
AND HUMID AIR MASS IN PLACE WITH TEMPS HOLDING ABOVE 80 THROUGH
MOST OF THE EVENING AND FALLING INTO THE UPPER 70S MOST PLACES BY
DAYBREAK.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 AM THURSDAY...DEEP DRY AIR AND WEAK SUBSIDENCE IN PLACE
UNDER EASTERN EXTENSION OF PLAINS 5H RIDGE WILL MINIMIZE PRECIP
CHANCES DURING THE PERIOD. FRI LOOKS THE BETTER OF THE 2 DAYS AS FAR
AS CONVECTION GOES...ESPECIALLY ALONG THE PIEDMONT TROUGH AND SEA
BREEZE. THERE IS PLENTY OF INSTABILITY...MLCAPE FRI AFTERNOON
APPROACHES 3K J/KG AND LAPSE RATES AROUND -8 C/KM...BUT THE
PRESENCE OF DEEP DRY AIR WILL LIKELY KEEP COVERAGE LIMITED TO
ISOLATED AT BEST. MOS NUMBERS HAVE BEEN TRENDING DOWN AND GIVEN THE
LACK OF CONVECTION THE PAST FEW DAYS SEE NO REASON TO CARRY A POP
HIGHER THAN SLIGHT CHANCE FRI AFTERNOON. SAT WILL BE MUCH THE SAME
AS FRI...THOUGH THE COLUMN WILL BE A LITTLE DRIER. PRECIPITABLE
WATER VALUES DROP FROM 1.7 FRI TO 1.5 SAT. ALSO WARMING ALOFT...AS
SUBSIDENCE STRENGTHENS...WILL LEAD TO A DECREASE IN OVERALL
INSTABILITY. CAPE VALUES DROP BELOW 2K J/KG ACROSS MUCH OF THE AREA.
STILL CARRY A SLIGHT CHANCE POP FOR SAT AFTERNOON...WITH BOTH THE
SEA BREEZE AND THE PIEDMONT TROUGH POSSIBLE TRIGGER MECHANISMS...BUT
NOW HAVE A SHORTER PERIOD OF LOW SLIGHT CHANCE POP SAT AFTERNOON.
LOW LEVEL WEST TO SOUTHWEST FLOW UNDER NORTH TO NORTHEAST FLOW ALOFT
WILL HELP KEEP THE SEA BREEZE PINNED CLOSER TO THE COAST. 850 TEMPS
IN THE LOWER 20C RANGE COMBINED WITH LIMITED INLAND PENETRATION OF
SEA BREEZE...ESPECIALLY SAT...SHOULD SEE WIDESPREAD HIGHS IN THE MID
TO UPPER 90S WITH TRIPLE DIGITS POSSIBLE. LOWS WILL BE IN THE MID
70S. HEAT INDEX VALUES ARE FORECAST TO BE 105-109 DURING EACH
AFTERNOON. THIS WOULD REQUIRING HEAT ADVISORIES FOR BOTH DAYS.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 3 AM THURSDAY...MEDIUM RANGE GUIDANCE SHOWS THE EASTERN
EXTENSION OF THE 5H RIDGE BREAKING DOWN LATE SUN. THIS PROBABLY
HAPPENS TO LATE FOR ANY SIGNIFICANT PRECIP FOR THE END OF THE
WEEKEND...HENCE SLIGHT CHANCE...BUT IT DOES BRING ABOUT A CHANGE TO
THE PATTERN ALOFT EARLY NEXT WEEK. A SERIES OF SHORTWAVE TROUGHS
WILL HELP DRIVE 5H TROUGH AXIS FARTHER AND FARTHER SOUTH. 00Z GFS
HAS COME IN FASTER THAN THE CANADIAN OR ECMWF SOLUTIONS...POSSIBLY
DUE TO ITS PROPENSITY TO OVER AMPLIFY SHORTWAVES. THUS FAVORED THE
SLOWER SOUTHWARD PUSH OF THE 5H TROUGH SEEN IN THE ECMWF/CANADIAN
SOLUTIONS. ACCOMPANYING THE 5H TROUGH AS IT HEADS SOUTH IS A COLD
FRONT AND DEEP MOISTURE. INITIALLY DEEPER MOISTURE IS MAINLY
ASSOCIATED WITH THE SURFACE BOUNDARY. ONCE THE 5H TROUGH SETS UP
WEST OF THE AREA...LATER TUE...DEEP SOUTHWEST FLOW WILL TAP INTO
GULF MOISTURE. PRECIPITABLE WATER VALUES JUMP FROM 1.8 TO OVER 2
INCHES LATE TUE AND WED. BASED ON THE DELAYED TIMING HAVE TRIMMED
BACK THE MON POP TO 40 WITH 40 TO 50 FOR TUE AND 40 FOR WED. ANY
PASSING SHORTWAVES WOULD LEAD TO AN INCREASE IN PRECIP COVERAGE AND
INTENSITY...BUT TIMING THESE FEATURES SEVERAL DAYS OUT IS NOT
FEASIBLE. TEMPERATURES ABOVE CLIMO SUN WITH A GRADUAL DOWNWARD TREND
IN BOTH HIGHS AND LOWS THROUGH THE PERIOD. HIGHS END UP BELOW CLIMO
TUE/WED WITH LOWS FALLING BACK TO CLIMO AT THE END OF THE PERIOD.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 18Z...MOST OF THE MODELS ARE NOT TOO ENTHUSED ABOUT CONVECTION
THIS AFTERNOON...THE EXCEPTION BEING THE NSSL WRF SHOWING A COMPLEX OF
STORMS DROPPING SOUTHEAST INTO THE REGION THIS AFTERNOON. FEEL THIS
MAY BE A BIT OVERDONE...WENT WITH VCTS IN THE TAFS. COULD NOT RULE
OUT A GOOD THUNDERSTORM...BEST CHANCE AT THE INLAND TERMINALS.
CONTINUED SOUTHWEST FLOW...A BIT GUSTY ALONG THE COAST.
TONIGHT...ISOLATED CONVECTION WILL BE WANING...WITH MID AND HIGH
CLOUD DEBRIS. CHANCE OF BRIEF MVFR FOG AROUND SUNRISE. LIGHT
SOUTHWEST FLOW...INCREASING WITH DAYTIME HEATING AND SUBSEQUENT
MIXING FRIDAY MORNING.
EXTENDED OUTLOOK...A CHANCE OF ISOLATED THUNDERSTORMS THROUGH THE
WEEKEND...POSSIBLY BECOMING MORE NUMEROUS MONDAY AND TUESDAY.
OTHERWISE EXPECT VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 130 PM THURSDAY...SOUTHWEST FLOW BETWEEN BERMUDA HIGH AND
PIEDMONT TROUGH OVER INLAND CAROLINAS WILL CONTINUE THROUGH
TONIGHT. NAM CONTINUES TO SHOW NOCTURNAL JET UP TO 25 KTS OVER THE
COASTAL WATERS OVERNIGHT. THE 975 MB WINDS ARE COMING IN CLOSE TO
35 KTS. OVERALL WILL SEE ENHANCED SEA BREEZE FLOW DIMINISH NEAR
SHORE THROUGH THIS EVENING BUT THIS JET ACROSS THE WATERS WILL
KEEP WINDS UP OVERNIGHT. SOUTHWEST WINDS 15 TO 20 KTS WILL KEEP
SEAS AROUND 3 TO 4 FT ACROSS MUCH OF THE WATERS THROUGH TONIGHT AND
COULD SPIKE AS HIGH AS 5 FT IN OUTERMOST WATERS.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 AM THURSDAY...BERMUDA HIGH AND PIEDMONT TROUGH WILL PRODUCE
THE TYPICAL SUMMER TIME SOUTHWEST FLOW OVER THE WATERS. SPEEDS WILL
RUN 10 TO 15 KT THROUGH THE PERIOD WITH A MARGINAL INCREASE EACH
AFTERNOON AS SEA BREEZE DEVELOPS AND PIEDMONT TROUGH BECOMES MORE
DEFINED. SEAS 2 TO 4 FT THROUGH THE PERIOD...A MIX OF THE DOMINANT
SOUTH TO SOUTHWEST WIND WAVE AND WEAK SOUTHEAST SWELL.
LONG TERM /SUNDAY THROUGH MONDAY/...
AS OF 3 AM THURSDAY...SOUTHWEST FLOW CONTINUES WITH WATERS BETWEEN
BERMUDA HIGH AND PIEDMONT TROUGH. GRADIENT BECOMES PINCHED SUN WITH
WINDS A SOLID 15 TO 20 KT. GRADIENT RELAXES SLIGHTLY FOR MON BUT
SPEEDS WILL STAY A SOLID 15 KT. WILL ONCE AGAIN SEE A SLIGHT
INCREASE IN SPEEDS EACH AFTERNOON AS SEA BREEZE DEVELOPS AND
PIEDMONT TROUGH BECOMES MORE DEFINED. INCREASED SPEEDS AND PROLONGED
PERIOD OF SOUTHWEST FETCH WILL RESULT IN A SLIGHT BUMP IN SPEEDS
DURING THE PERIOD. SEAS 3 TO 4 FT BUILD TO 3 TO 5 FT LATE EACH
DAY...MAINLY MADE UP OF SHORT PERIOD SOUTHWEST WIND WAVE. SCEC WILL
BE POSSIBLE EACH AFTERNOON.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...HEAT ADVISORY UNTIL 9 PM EDT THIS EVENING FOR SCZ017-023-024-
032-033-039-053>056.
NC...HEAT ADVISORY UNTIL 9 PM EDT THIS EVENING FOR NCZ087-096-099-
105-107-109.
MARINE...NONE.
&&
$$
NEAR TERM...RGZ
SHORT TERM...III
LONG TERM...III
AVIATION...RGZ/DL
AREA FORECAST DISCUSSION
NWS RALEIGH NC
220 PM EDT THU JUL 5 2012
.SYNOPSIS...
AN UPPER LEVEL RIDGE EXTENDING EASTWARD FROM THE CENTRAL MISSISSIPPI
RIVER VALLEY TOWARD THE CAROLINAS WILL RESULT IN ABOVE NORMAL
TEMPERATURES THROUGH THE UPCOMING WEEKEND...WITH A CHANCE FOR
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON
AND EVENING HOURS EACH DAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1130 AM THURSDAY...
OVERVIEW:
NORTHWEST FLOW ALOFT WILL PREVAIL OVER THE CAROLINAS THROUGH
TONIGHT...ON THE EASTERN PERIPHERY OF AN UPPER LEVEL RIDGE CENTERED
OVER THE CENTRAL MS RIVER VALLEY. 14Z WV IMAGERY AND RUC DATA
INDICATED MULTIPLE MID/UPPER LEVEL DISTURBANCES EMBEDDED WITHIN NW
FLOW ALOFT OVER THE MID-ATLANTIC AND CAROLINAS.
TEMPERATURES:
THE 12Z GSO RAOB INDICATED A 1000-850 MB THICKNESS OF 1434 METERS
THIS MORNING. THIS IS CONSISTENT WITH THE LATEST MODEL GUIDANCE...
WHICH CONTINUES TO INDICATE 1000-850 MB THICKNESSES IN VICINITY OF
1455 METERS BY 00Z...ROUGHLY 10-15 METERS HIGHER THAN YESTERDAY.
MODEL GUIDANCE INDICATES H85 TEMPS IN THE 21-23C RANGE THIS
AFTERNOON...GENERALLY CONSISTENT WITH UPSTREAM CONDITIONS PER 14Z
SPC MESOANALYSIS (THOUGH COOLER TEMPS ARE PRESENT OVER WV IN ASSOC/W
MCS REMNANTS). HIGHS YESTERDAY RANGED FROM 95-98F IN MOST
LOCATIONS...RDU AN EXCEPTION AT 101F. BASED ON YESTERDAY`S TEMPS AND
A 10-15 METER INCREASE IN THICKNESSES...EXPECT HIGHS IN VICINITY OF
100F TODAY...THOUGH ISOLD/SCT CONVECTION MAY PREVENT HIGHS FROM
EXCEEDING THE MID/UPPER 90S IN SOME LOCATIONS. DECIDED TO INCREASE
THE HIGH AT RDU TO 102F BASED ON YESTERDAY`S READING. WILL DECREASE
HIGHS A FEW DEGREES LOWER THAN WHAT THICKNESSES SUGGEST IN THE FAR
NW PIEDMONT WHERE OUTFLOW FROM MCS REMNANTS (AND NEWLY DEVELOPED
CONVECTION NEAR BLUEFIELD WV) MAY AFFECT TEMPS BY EARLY/MID
AFTERNOON. H85 DEWPOINTS RANGED FROM 13-15C (55-60F) ACROSS THE AREA
AT 14Z...AND SHOULD REMAIN IN THAT VICINITY THROUGH THE AFTERNOON.
GIVEN STRONG HEATING AND MIXING UP TO AT LEAST H85...ANTICIPATE THAT
DEWPOINTS WILL MIX OUT INTO THE LOWER/MID 60S IN THE NORTHERN AND
WESTERN PIEDMONT. IN THE SANDHILLS AND COASTAL PLAIN ON THE EASTERN
PERIPHERY OF THE LEE TROUGH...EXPECT DEWPOINTS WILL LIKELY REMAIN IN
THE UPPER 60S TO LOWER 70S GIVEN RELATIVELY HIGHER H85 DEWPOINTS IN
THE PRESENCE OF SHALLOW LOW-LEVEL CONVERGENCE AND MOISTURE POOLING.
EXPECT OVERNIGHT LOWS A BIT WARMER THAN THIS MORNING DUE TO AIRMASS
MODIFICATION...IN THE LOWER/MID 70S...OR 72-75F.
HEAT INDICES/HEAT ADVISORY:
WITH THE ABOVE T/TD DISCUSSION IN MIND...ANTICIPATE MAX HEAT INDICES
BETWEEN 105-110F IN THE ADVISORY AREA...WITH HEAT INDICES
APPROACHING 105F IN THE TRIANGLE...AND GENERALLY 100-105F IN THE
WESTERN PIEDMONT. DESPITE MAX HEAT INDICES FORECAST NEAR 105F IN
WAKE/FRANKLIN/WARREN COUNTIES...DECIDED NOT TO EXPAND THE HEAT
ADVISORY TO INCLUDE THOSE COUNTIES GIVEN A FAIR AMOUNT OF
UNCERTAINTY W/REGARD TO DEWPOINTS ALONG/WEST OF HWY 1 AND CONVECTIVE
EVOLUTION MID/LATE AFTERNOON.
PRECIPITATION CHANCES:
MID-LEVEL LAPSE RATES ARE SEASONABLY STEEP TODAY ACCORDING TO 15Z
SPC MESOANALYSIS DATA...IN VICINITY OF 6.5 C/KM. GIVEN SURFACE TEMPS
EASILY IN THE MID/UPPER 90S AND DEWPOINTS RANGING FROM THE LOWER/MID
60S TO NEAR 70F (IN ANTICIPATION OF SOME MIX-DOWN BY 18-21Z)...
EXPECT MLCAPE VALUES SOLIDLY IN THE MODERATE RANGE...PERHAPS
STRONG...GENERALLY BETWEEN 1500-2500 J/KG. W/REGARD TO FORCING... A
COMPLEX NW FLOW ALOFT PATTERN IS PRESENT OVER CENTRAL NC...WITH AT
LEAST SEVERAL IMPORTANT FEATURES. 1) A SHORTWAVE IN VICINITY OF CAPE
FEAR IS PROGGED TO TRACK SOUTHWARD INTO EASTERN SC/OFFSHORE AS THE
AFTERNOON PROGRESSES...AND SUBSIDENCE IN THE WAKE OF THIS FEATURE
MAY INITIALLY SUPPRESS DEVELOPMENT OVER THE COASTAL PLAIN...
ESPECIALLY IN THE SE COASTAL PLAIN. 2) THE REMNANTS OF AN MCS OVER
NORTHERN VA AT 03Z HAVE PROGRESSED INTO CENTRAL NC EARLY THIS
AFTERNOON. HOWEVER...FORCING ASSOC/W THIS FEATURE IS DIFFICULT TO
ASCERTAIN. 3) THE REMNANTS OF AN MCS OVER OHIO AT 03Z HAVE
PROGRESSED INTO SOUTHWEST VA BY 17Z THIS AFTERNOON...ALREADY FORCING
CONVECTION ALONG THE I-77 CORRIDOR IN NORTHWEST NC. 4) AN ONGOING
MCS IN WV AT 17Z...THOUGH EXPECTED TO TRACK INTO THE FAR WESTERN
PORTIONS OF THE STATE. ADDITIONALLY...A SURFACE TROUGH AXIS IN
VICINITY OF THE HWY 1 CORRIDOR WILL PROVIDE A LOW-LEVEL FOCUS FOR
CONVECTION THIS AFT/EVE. WITH THE ABOVE IN MIND...WILL INDICATE
PRECIP CHANCES 30-40% IN THE FAR WESTERN PIEDMONT...AND 20-30% IN
VICINITY OF THE HWY 1 CORRIDOR...AND ~20% IN THE CENTRAL/SE COASTAL
PLAIN.
SEVERE THREAT:
MLCAPE SOLIDLY IN THE MODERATE RANGE WILL RESULT IN ROBUST UPDRAFTS
TODAY...THOUGH DEEP-LAYER SHEAR WILL BE NO MORE THAN 15-20 KT.
HOWEVER...DUE TO LARGE T/TD SPREADS AND VERY HIGH DCAPE VALUES
ANALYZED PER LATEST SPC MESOANALYSIS (1000-1600 J/KG...HIGHEST
WEST)...EXPECT MULTICELL ORGANIZATION PRIMARILY ALONG OUTFLOW.
THOUGH HAIL UP TO THE SIZE OF QUARTERS WILL BE POSSIBLE GIVEN
MODERATE INSTABILITY...THE PRIMARY THREAT WILL BE ASSOCIATED WITH
DAMAGING WINDS OWING TO VERY HIGH DCAPE VALUES/STRONG BOUNDARY LAYER
EVAPORATIVE COOLING POTENTIAL. THE THREAT FOR SEVERE WEATHER WILL BE
HIGHEST IN THE WESTERN PIEDMONT (WHERE THE SLIGHT RISK IS INDICATED
ON THE DAY 1 OUTLOOK) BETWEEN 1 PM THIS AFTERNOON AND 8-11 PM THIS
EVENING. THIS IS WHERE THE HIGHEST DCAPE VALUES ARE PRESENT AND
WHERE THE RELATIVE BEST MID LEVEL FORCING IS EXPECTED AS REMNANT MCS
ACTIVITY PROGRESSES SOUTH/SSW INTO WESTERN PORTIONS OF THE STATE.
ISOLATED SEVERE WEATHER WILL BE POSSIBLE ELSEWHERE CONVECTION IS
PRESENT OWING TO 1000+ J/KG OF DCAPE/STEEP LOW-LEVEL LAPSE RATES IN
THE PRESENCE OF MODERATE INSTABILITY. -VINCENT
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 220 PM THURSDAY...
THE MID LEVEL RIDGE CURRENTLY CENTERED TO OUR WEST OVER THE CENTRAL
PLAINS WILL EXPAND EASTWARD AS THE TROUGH OFF THE NEW ENGLAND COAST
MOVES EAST. AT THE SFC AND LOWER LEVELS...NOT MUCH WILL CHANGE WITH
THE LEE TROUGH REMAINING IN PLACE. LOW LEVEL THICKNESSES ARE PROGGED
TO REMAIN THE SAME...THUS EXPECT HIGHS TOMORROW VERY SIMILAR TO
TODAYS VALUES...AROUND 100 ACROSS MUCH OF OUR CWA. GUIDANCE IS IN
GOOD AGREEMENT THAT DWPTS WILL BE LOWER ACROSS OUR WESTERN ZONES
(UPPER 60S WEST TO LOWER 70S EAST)...THUS HEAT INDEX VALUES WILL
RANGE FROM 100-103 WEST TO 104-107 EAST. THE HEAT ADVISORY THAT IS
ALREADY IN EFFECT FROM 11 AM TO 8 PM FRIDAY LOOKS GOOD AND WILL
LEAVE AS-IS. AS FOR TSTM POTENTIAL ON FRIDAY...NOTED SUBTLE
MID-LEVEL WARMING IN FORECAST SOUNDINGS BUT STILL ENOUGH MOISTURE
AND INSTABILITY/CAPE TO SEE SOME AFTERNOON TSTMS. GFS DEPICTS A WEAK
MID LEVEL SHEAR AXIS MOVING SOUTHEAST ACROSS THE STATE LATE IN THE
DAY. THUS EXPECT ISOLATED TO SCATTERED TSTMS...WITH PERHAPS THE
BETTER CHANCE FOR TSTMS ACTIVITY AND STRONGER INTENSITY WILL BE
ACROSS OUR EASTERN PIEDMONT AND COASTAL PLAIN ZONES WHERE FORECAST
SOUNDINGS AND SFC DWPT PROGS SUGGEST BETTER CAPE. ANY ACTIVITY WILL
WIND DOWN DURING THE LATE EVENING WITH PC CONDITIONS AT NIGHT. LOWS
FRI NIGHT IN THE LOW-MID 70S.
ON SATURDAY THE MID LEVEL RIDGE WILL BUILD OVER TOP OF CENTRAL NC...
WITH CONTINUED MID LEVEL WARMING. WITH 850 MB TEMPS WARMING AND LOW
LEVEL THICKNESSES INCREASING...EXPECT ANOTHER HOT DAY WITH HIGHS
ONCE AGAIN AROUND 100. HEAT ADVISORIES MAY ONCE AGAIN BE NEEDED.
WITH THE AFOREMENTIONED MID LEVEL WARMING AND WEAKENING LAPSE
RATES...TSTM COVERAGE SHOULD BE FURTHER REDUCED. BEST CHANCE WILL
CONTINUE TO BE ACROSS OUR EASTERN ZONES WHERE HIGHER PW AND DWPTS
ARE LOCATED. LITTLE CHANGE SATURDAY NIGHT...LOWS IN THE MID 70S.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 220 PM THURSDAY...
ON SUNDAY THE MID LEVEL RIDGE WILL MOVE EAST AS A POTENT SHORT WAVE
MOVES SE ACROSS THE GREAT LAKES. A COLD FRONT WILL BE MOVING ACROSS
THE OH RIVER VALLEY. SUNDAY SHOULD BE THE LAST HOT DAY IN THE
FORECAST PERIOD WITH LITTLE OR NO AIRMASS CHANGE FROM PREVIOUS DAYS.
EXPECT HIGHS ONCE AGAIN AROUND 100. WITH MID LEVELS BEGINNING TO
COOL AND PWAT INCREASING AHEAD OF THE TROUGH...WILL CONTINUE WITH
ISOLD TO SCATTERED AFTERNOON AND EVENING TSTMS.
MONDAY WILL BE A TRANSITION DAY AS THE LONGWAVE TROUGH DEEPENS
ACROSS THE EASTERN HALF OF THE COUNTRY AND THE ASSOC COLD FRONT
STALLS ACROSS THE CAROLINAS. THIS PATTERN WILL THEN REMAIN WITH US
THROUGH MUCH OF THE WEEK...RESULTING IN AT LEAST A GOOD CHANCE FOR
SHOWERS AND TSTMS EACH DAY AND NEAR SEASONABLE TEMPS.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 720 AM THURSDAY...
A FEW LOCATIONS ARE REPORTING 4-6SM VSBYS THIS MORNING...BUT THEY
ARE VERY ISOLATED...WITH MOST LOCATIONS REPORTING VFR CONDITIONS.
SCATTERED STORMS WILL BE POSSIBLE AGAIN THIS AFTERNOON ALONG AND
SOUTH OF A PERSISTENT PIEDMONT TROUGH OVER CENTRAL NC...AND POSSIBLY
OVER THE WESTERN PIEDMONT AS AN UPPER LEVEL DISTURBANCE HELPS
TRIGGER STORMS IN OVER THE HIGHER TERRAIN. HOWEVER...CONFIDENCE IN
ANY IMPACTS AT TAF SITES REMAINS TOO LOW FOR MENTION OF THUNDER IN
THE CURRENT TAF PACKAGE.
OUTLOOK....
PREDOMINATELY VFR CONDITIONS ARE EXPECTED THROUGH THE WEEKEND AS A
STRONG UPPER LEVEL RIDGE BUILDS BACK EAST OVER THE REGION. A FEW
ISOLATED THUNDERSTORMS WILL ALSO BE POSSIBLE DURING THIS PERIOD. AN
APPROACHING COLD FRONT SHOULD BRING A BETTER CHANCE OF
SHOWERS/STORMS AND ADVERSE AVIATION CONDITIONS EARLY NEXT WEEK.
&&
.CLIMATE...
HIGH TEMPERATURE RECORDS AND YEAR RECORD LAST SET.
RALEIGH-DURHAM... GREENSBORO...
07/05 102 1999 98 1990
07/06 102 1999 100 1977
07/07 102 2010 101 1977
07/08 103 1977 102 1977
FAYETTEVILLE...
07/05 101 2002
07/06 99 1990
07/07 103 2010
07/08 102 1977
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY FROM 11 AM THIS MORNING TO 9 PM EDT THIS EVENING
FOR NCZ011-027-028-042-043-077-078-085-086-088-089.
HEAT ADVISORY FROM 11 AM TO 8 PM EDT FRIDAY FOR NCZ008>011-
025>028-040>043-074>078-083>086-088-089.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT
SHORT TERM...NP
LONG TERM...NP
AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS RALEIGH NC
120 PM EDT THU JUL 5 2012
.SYNOPSIS...
AN UPPER LEVEL RIDGE EXTENDING EASTWARD FROM THE CENTRAL MISSISSIPPI
RIVER VALLEY TOWARD THE CAROLINAS WILL RESULT IN ABOVE NORMAL
TEMPERATURES TODAY THROUGH THE UPCOMING WEEKEND...WITH A CHANCE FOR
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON
AND EVENING HOURS EACH DAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1130 AM THURSDAY...
OVERVIEW:
NORTHWEST FLOW ALOFT WILL PREVAIL OVER THE CAROLINAS THROUGH
TONIGHT...ON THE EASTERN PERIPHERY OF AN UPPER LEVEL RIDGE CENTERED
OVER THE CENTRAL MS RIVER VALLEY. 14Z WV IMAGERY AND RUC DATA
INDICATED MULTIPLE MID/UPPER LEVEL DISTURBANCES EMBEDDED WITHIN NW
FLOW ALOFT OVER THE MID-ATLANTIC AND CAROLINAS.
TEMPERATURES:
THE 12Z GSO RAOB INDICATED A 1000-850 MB THICKNESS OF 1434 METERS
THIS MORNING. THIS IS CONSISTENT WITH THE LATEST MODEL GUIDANCE...
WHICH CONTINUES TO INDICATE 1000-850 MB THICKNESSES IN VICINITY OF
1455 METERS BY 00Z...ROUGHLY 10-15 METERS HIGHER THAN YESTERDAY.
MODEL GUIDANCE INDICATES H85 TEMPS IN THE 21-23C RANGE THIS
AFTERNOON...GENERALLY CONSISTENT WITH UPSTREAM CONDITIONS PER 14Z
SPC MESOANALYSIS (THOUGH COOLER TEMPS ARE PRESENT OVER WV IN ASSOC/W
MCS REMNANTS). HIGHS YESTERDAY RANGED FROM 95-98F IN MOST
LOCATIONS...RDU AN EXCEPTION AT 101F. BASED ON YESTERDAY`S TEMPS AND
A 10-15 METER INCREASE IN THICKNESSES...EXPECT HIGHS IN VICINITY OF
100F TODAY...THOUGH ISOLD/SCT CONVECTION MAY PREVENT HIGHS FROM
EXCEEDING THE MID/UPPER 90S IN SOME LOCATIONS. DECIDED TO INCREASE
THE HIGH AT RDU TO 102F BASED ON YESTERDAY`S READING. WILL DECREASE
HIGHS A FEW DEGREES LOWER THAN WHAT THICKNESSES SUGGEST IN THE FAR
NW PIEDMONT WHERE OUTFLOW FROM MCS REMNANTS (AND NEWLY DEVELOPED
CONVECTION NEAR BLUEFIELD WV) MAY AFFECT TEMPS BY EARLY/MID
AFTERNOON. H85 DEWPOINTS RANGED FROM 13-15C (55-60F) ACROSS THE AREA
AT 14Z...AND SHOULD REMAIN IN THAT VICINITY THROUGH THE AFTERNOON.
GIVEN STRONG HEATING AND MIXING UP TO AT LEAST H85...ANTICIPATE THAT
DEWPOINTS WILL MIX OUT INTO THE LOWER/MID 60S IN THE NORTHERN AND
WESTERN PIEDMONT. IN THE SANDHILLS AND COASTAL PLAIN ON THE EASTERN
PERIPHERY OF THE LEE TROUGH...EXPECT DEWPOINTS WILL LIKELY REMAIN IN
THE UPPER 60S TO LOWER 70S GIVEN RELATIVELY HIGHER H85 DEWPOINTS IN
THE PRESENCE OF SHALLOW LOW-LEVEL CONVERGENCE AND MOISTURE POOLING.
EXPECT OVERNIGHT LOWS A BIT WARMER THAN THIS MORNING DUE TO AIRMASS
MODIFICATION...IN THE LOWER/MID 70S...OR 72-75F.
HEAT INDICES/HEAT ADVISORY:
WITH THE ABOVE T/TD DISCUSSION IN MIND...ANTICIPATE MAX HEAT INDICES
BETWEEN 105-110F IN THE ADVISORY AREA...WITH HEAT INDICES
APPROACHING 105F IN THE TRIANGLE...AND GENERALLY 100-105F IN THE
WESTERN PIEDMONT. DESPITE MAX HEAT INDICES FORECAST NEAR 105F IN
WAKE/FRANKLIN/WARREN COUNTIES...DECIDED NOT TO EXPAND THE HEAT
ADVISORY TO INCLUDE THOSE COUNTIES GIVEN A FAIR AMOUNT OF
UNCERTAINTY W/REGARD TO DEWPOINTS ALONG/WEST OF HWY 1 AND CONVECTIVE
EVOLUTION MID/LATE AFTERNOON.
PRECIPITATION CHANCES:
MID-LEVEL LAPSE RATES ARE SEASONABLY STEEP TODAY ACCORDING TO 15Z
SPC MESOANALYSIS DATA...IN VICINITY OF 6.5 C/KM. GIVEN SURFACE TEMPS
EASILY IN THE MID/UPPER 90S AND DEWPOINTS RANGING FROM THE LOWER/MID
60S TO NEAR 70F (IN ANTICIPATION OF SOME MIX-DOWN BY 18-21Z)...
EXPECT MLCAPE VALUES SOLIDLY IN THE MODERATE RANGE...PERHAPS
STRONG...GENERALLY BETWEEN 1500-2500 J/KG. W/REGARD TO FORCING... A
COMPLEX NW FLOW ALOFT PATTERN IS PRESENT OVER CENTRAL NC...WITH AT
LEAST SEVERAL IMPORTANT FEATURES. 1) A SHORTWAVE IN VICINITY OF CAPE
FEAR IS PROGGED TO TRACK SOUTHWARD INTO EASTERN SC/OFFSHORE AS THE
AFTERNOON PROGRESSES...AND SUBSIDENCE IN THE WAKE OF THIS FEATURE
MAY INITIALLY SUPPRESS DEVELOPMENT OVER THE COASTAL PLAIN...
ESPECIALLY IN THE SE COASTAL PLAIN. 2) THE REMNANTS OF AN MCS OVER
NORTHERN VA AT 03Z HAVE PROGRESSED INTO CENTRAL NC EARLY THIS
AFTERNOON. HOWEVER...FORCING ASSOC/W THIS FEATURE IS DIFFICULT TO
ASCERTAIN. 3) THE REMNANTS OF AN MCS OVER OHIO AT 03Z HAVE
PROGRESSED INTO SOUTHWEST VA BY 17Z THIS AFTERNOON...ALREADY FORCING
CONVECTION ALONG THE I-77 CORRIDOR IN NORTHWEST NC. 4) AN ONGOING
MCS IN WV AT 17Z...THOUGH EXPECTED TO TRACK INTO THE FAR WESTERN
PORTIONS OF THE STATE. ADDITIONALLY...A SURFACE TROUGH AXIS IN
VICINITY OF THE HWY 1 CORRIDOR WILL PROVIDE A LOW-LEVEL FOCUS FOR
CONVECTION THIS AFT/EVE. WITH THE ABOVE IN MIND...WILL INDICATE
PRECIP CHANCES 30-40% IN THE FAR WESTERN PIEDMONT...AND 20-30% IN
VICINITY OF THE HWY 1 CORRIDOR...AND ~20% IN THE CENTRAL/SE COASTAL
PLAIN.
SEVERE THREAT:
MLCAPE SOLIDLY IN THE MODERATE RANGE WILL RESULT IN ROBUST UPDRAFTS
TODAY...THOUGH DEEP-LAYER SHEAR WILL BE NO MORE THAN 15-20 KT.
HOWEVER...DUE TO LARGE T/TD SPREADS AND VERY HIGH DCAPE VALUES
ANALYZED PER LATEST SPC MESOANALYSIS (1000-1600 J/KG...HIGHEST
WEST)...EXPECT MULTICELL ORGANIZATION PRIMARILY ALONG OUTFLOW.
THOUGH HAIL UP TO THE SIZE OF QUARTERS WILL BE POSSIBLE GIVEN
MODERATE INSTABILITY...THE PRIMARY THREAT WILL BE ASSOCIATED WITH
DAMAGING WINDS OWING TO VERY HIGH DCAPE VALUES/STRONG BOUNDARY LAYER
EVAPORATIVE COOLING POTENTIAL. THE THREAT FOR SEVERE WEATHER WILL BE
HIGHEST IN THE WESTERN PIEDMONT (WHERE THE SLIGHT RISK IS INDICATED
ON THE DAY 1 OUTLOOK) BETWEEN 1 PM THIS AFTERNOON AND 8-11 PM THIS
EVENING. THIS IS WHERE THE HIGHEST DCAPE VALUES ARE PRESENT AND
WHERE THE RELATIVE BEST MID LEVEL FORCING IS EXPECTED AS REMNANT MCS
ACTIVITY PROGRESSES SOUTH/SSW INTO WESTERN PORTIONS OF THE STATE.
ISOLATED SEVERE WEATHER WILL BE POSSIBLE ELSEWHERE CONVECTION IS
PRESENT OWING TO 1000+ J/KG OF DCAPE/STEEP LOW-LEVEL LAPSE RATES IN
THE PRESENCE OF MODERATE INSTABILITY. -VINCENT
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 230 AM THURSDAY...
FOR FRIDAY/FRIDAY NIGHT: CONTINUED WARM AND HUMID. THE SURFACE FRONT
IS EXPECTED TO EXTEND FROM EASTERN AND NORTHERN VA NORTHWARD THROUGH
THE CENTRAL APPALACHIANS THEN WESTWARD ACROSS MI AND THE UPPER
MIDWEST EARLY FRIDAY... WITH THE SURFACE LEE TROUGH PERSISTING
THROUGH CENTRAL NC. THE NAM/GFS SUGGEST THAT A SUBTLE UPPER LEVEL
SHEAR AXIS WILL DROP SOUTHWARD THROUGH NC BY EARLY AFTERNOON. WHILE
THIS MIGHT BE A BYPRODUCT OF UPSTREAM MCS ACTIVITY... THE SUBPAR
PERFORMANCE OF BOTH MODELS WITH THE CURRENT CONVECTION NEAR THE
OH/WV BORDER INTO SW PA GREATLY REDUCES CONFIDENCE IN THE SUBSEQUENT
MODEL DETAILS. WHILE IT IS CERTAINLY REASONABLE TO EXPECT THAT WE
MIGHT BE AFFECTED BY AN UPSTREAM MCV SOMETIME FRIDAY BASED ON THE
ONGOING LONGWAVE PATTERN OVER THE CONUS... THE MID LEVEL RIDGE
CENTERED OVER NRN MISSOURI WILL STEADILY EXPAND EASTWARD THROUGH THE
MIDATLANTIC REGION THROUGH FRIDAY NIGHT... RESULTING IN AROUND A
20-30 METER MID LEVEL HEIGHT RISE OVER NC AND LIKELY CAUSING A
SOUTH-SOUTHWESTWARD DEFLECTION IN MOVEMENT OF ANY SUCH MCV TOWARD
THE SRN APPALACHIANS / WRN NC... WHERE 850-500 MB LAPSE RATES ARE
EXPECTED TO BE 6.75-7.0 C/KM. HOWEVER... INSTABILITY WILL REMAIN
MODERATE TO BORDERLINE STRONG IN THE AFTERNOON AND EVENING OVER
CENTRAL NC WITH MLCAPE OF 1500-2800 J/KG... AND WITH MARGINAL BUT
SUFFICIENT DEEP LAYER SHEAR NEAR 20 KTS. SO EVEN IN THE ABSENCE OF
CONSIDERABLE DYNAMIC SUPPORT FOR ORGANIZATION OF CONVECTION... WE
SHOULD STILL SEE ISOLATED TO SCATTERED COVERAGE WITH PRECIP WATER
VALUES EXPECTED TO REACH 1.8-1.9 INCHES... ABOUT 150% OF NORMAL.
THIS SHOULD RESULT IN ONLY MINOR CHANGES TO THE EARLIER FORECAST. WE
MAY SEE A STRONG STORM OR TWO PRODUCING GUSTY WINDS AS WELL AS SOME
HAIL GIVEN THAT CAPE IN THE -10C TO -30C IS EXPECTED TO EXCEED 1000
J/KG WITH NORMALIZED CAPE OVER 0.20 M/S2. LOW LEVEL THICKNESSES --
WHICH ARE PROJECTED TO CHANGE VERY LITTLE DAY-TO-DAY THROUGH THE
UPCOMING WEEKEND -- POINT TO HIGHS ONCE AGAIN A FEW OF DEGREES
EITHER SIDE OF 100 ACROSS THE AREA... WHICH CLOSELY FOLLOWS
PERSISTENCE. SURFACE DEW POINT FORECAST INDICATE ANOTHER HEAT
ADVISORY IS NEEDED FOR ALL OF CENTRAL NC EXCLUDING THE TRIAD REGION.
MODELS INDICATE LINGERING ELEVATED INSTABILITY OVERNIGHT... BUT WITH
PROJECTIONS OF WANING PRECIP WATER AND CONFLUENT MID-UPPER LEVELS...
WE SHOULD SEE A 10 PERCENT OR LOWER COVERAGE OF NIGHTTIME PRECIP...
SO WILL KEEP THE FORECAST DRY OVERNIGHT. LOWS 71-76.
FOR SATURDAY/SATURDAY NIGHT: STILL HOT WITH EVEN LOWER COVERAGE OF
CONVECTION. AS THE MID LEVEL RIDGE AXIS CONTINUES TO BUILD EASTWARD
THROUGH NC... MID LEVEL LAPSE RATES SLIP TO JUST 6.0-6.25 C/KM WITH
DRYING ALOFT. LOW LEVEL FLOW STRENGTHENS FROM THE SOUTHWEST DUE TO
THE INCREASING MSLP GRADIENT BETWEEN THE SURFACE HIGH OFF THE
SOUTHEAST COAST AND THE SOUTHWARD-DRIFTING SYNOPTIC COOL FRONT
DROPPING TOWARD THE OHIO VALLEY... AND WE SHOULD SEE A WEAKENING OF
THE LEE TROUGH WITH DIMINISHING MID LEVEL WINDS. WITH CONTINUED
STRONG SURFACE HEATING... WILL NOT GO ENTIRELY DRY BUT WILL RESTRICT
PRECIP CHANCES TO EASTERN SECTIONS WHERE HIGHER PRECIP WATER AND
SURFACE DEW POINTS WILL RESIDE... AND WILL CONFINE ISOLATED
THUNDERSTORMS TO MID AFTERNOON INTO THE EVENING. HIGHS AGAIN 98-102.
PREDICTED AFTERNOON DEW POINTS SHOULD SUPPORT YET ANOTHER DAY OF
HIGH HEAT INDEX VALUES... AND MORE HEAT ADVISORIES MAY BE
REQUIRED... ALTHOUGH THE SOUTHWEST WINDS MAY ALLOW FOR GREATER
MIXING OUT OF DEW POINTS WHICH COULD SUPPRESS HEAT INDICES A BIT.
BREEZES STAYING UP OVERNIGHT SHOULD KEEP TEMPS ELEVATED OVERNIGHT...
THUS ANTICIPATE WARMER LOWS OF 74-78. -GIH
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 250 AM THURSDAY...
FOR SUNDAY/SUNDAY NIGHT: THE MID LEVEL RIDGE WILL CONTINUE TO EXTEND
ACROSS NC BUT WILL HAVE BECOME STRETCHED AND WEAKENED WITH LOWERING
HEIGHTS OVER THE MIDATLANTIC... FORESHADOWING A PATTERN CHANGE AS A
CANADIAN VORTEX DEEPENS OVER THE BORDER OF QUEBEC WITH LABRADOR. AS
THE LONGWAVE TROUGH BEGINS TO AMPLIFY OVER THE NORTHEAST QUARTER OF
THE COUNTRY... THE SURFACE COOL FRONT SHOULD DROP SOUTHWARD TOWARD
THE VA/NC STATE LINE... ALTHOUGH HOW FAR SOUTHWARD IS DIFFICULT TO
PINPOINT AT THIS RANGE. BUT GFS/ECMWF THICKNESSES REMAIN QUITE
HIGH... AND EXPECT THE HEAT TO HOLD FOR ONE MORE DAY... WITH JUST
ISOLATED STORM CHANCES AS THE MID LEVELS REMAIN RATHER WARM AND DRY.
HIGHS AGAIN CLOSE TO 100 WITH MORNING THICKNESSES IN THE 1430-1435
METER RANGE. LOWS IN THE MID-UPPER 70S WITH LOW LEVEL MOISTURE
LIKELY TO POOL AHEAD OF THE FRONT.
FOR MONDAY THROUGH WEDNESDAY: AN END TO THE HEAT WAVE MAY BE IN
SIGHT. THE FRONT IS EXPECTED TO DROP INTO THE REGION MONDAY AS THE
LONGWAVE TROUGH DIGS SOUTHWARD THROUGH THE APPALACHIANS AND MID
SOUTH. INCREASING DEEP LAYER SHEAR... RISING MOISTURE THROUGH THE
COLUMN... AND DYNAMIC FORCING FOR ASCENT SHOULD RESULT IN A GOOD
CHANCE OF SHOWERS AND STORMS EARLY IN THE WORK WEEK. THE SOUTHERN
PORTION OF THE LONGWAVE TROUGH MAY WEAKEN A BIT TOWARD WEDNESDAY BUT
SHOULD STILL HOLD OVER OR JUST WEST OF THE FORECAST AREA... ROUGHLY
ALONG THE SPINE OF THE APPALACHIANS. WITH THIS PATTERN... THE
SURFACE FRONT IS LIKELY TO STALL OUT OVER THE CENTRAL CAROLINAS WITH
A GENERAL WEAKENING TREND IN BOTH THE MSLP AND LOW LEVEL WIND
FIELDS... TYPICAL FOR JULY IN NC. THIS SHOULD LEAVE US WITHIN A
STEADY STREAM OF WEAK MID LEVEL PERTURBATIONS WITH A CONTINUED
TAPPING OF LOW AND MID LEVEL MOISTURE FROM THE GULF. EXPECT AT LEAST
SCATTERED SHOWERS AND STORMS EACH DAY. THICKNESSES HEAD BACK DOWN TO
SEASONAL NORMALS ALTHOUGH THIS MAY BE DUE IN PART TO INCREASED
CLOUDINESS... INDICATIVE OF HIGHS NEAR OR JUST UNDER NORMAL HIGHS
BUT WITH ABOVE-NORMAL LOWS. -GIH
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 720 AM THURSDAY...
A FEW LOCATIONS ARE REPORTING 4-6SM VSBYS THIS MORNING...BUT THEY
ARE VERY ISOLATED...WITH MOST LOCATIONS REPORTING VFR CONDITIONS.
SCATTERED STORMS WILL BE POSSIBLE AGAIN THIS AFTERNOON ALONG AND
SOUTH OF A PERSISTENT PIEDMONT TROUGH OVER CENTRAL NC...AND POSSIBLY
OVER THE WESTERN PIEDMONT AS AN UPPER LEVEL DISTURBANCE HELPS
TRIGGER STORMS IN OVER THE HIGHER TERRAIN. HOWEVER...CONFIDENCE IN
ANY IMPACTS AT TAF SITES REMAINS TOO LOW FOR MENTION OF THUNDER IN
THE CURRENT TAF PACKAGE.
OUTLOOK....
PREDOMINATELY VFR CONDITIONS ARE EXPECTED THROUGH THE WEEKEND AS A
STRONG UPPER LEVEL RIDGE BUILDS BACK EAST OVER THE REGION. A FEW
ISOLATED THUNDERSTORMS WILL ALSO BE POSSIBLE DURING THIS PERIOD. AN
APPROACHING COLD FRONT SHOULD BRING A BETTER CHANCE OF
SHOWERS/STORMS AND ADVERSE AVIATION CONDITIONS EARLY NEXT WEEK.
&&
.CLIMATE...
HIGH TEMPERATURE RECORDS AND YEAR RECORD LAST SET.
RALEIGH-DURHAM... GREENSBORO...
07/05 102 1999 98 1990
07/06 102 1999 100 1977
07/07 102 2010 101 1977
07/08 103 1977 102 1977
FAYETTEVILLE...
07/05 101 2002
07/06 99 1990
07/07 103 2010
07/08 102 1977
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY FROM 11 AM THIS MORNING TO 9 PM EDT THIS EVENING
FOR NCZ011-027-028-042-043-077-078-085-086-088-089.
HEAT ADVISORY FROM 11 AM TO 8 PM EDT FRIDAY FOR NCZ008>011-
025>028-040>043-074>078-083>086-088-089.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT
SHORT TERM...HARTFIELD
LONG TERM...HARTFIELD
AVIATION...KRR/SMITH
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
341 PM CDT THU JUL 5 2012
.SHORT TERM...
TONIGHT AND FRIDAY...FORECAST CONFIDENCE IS MEDIUM.
ANOTHER DAY OF RECORD BREAKING HIGH TEMPERATURES CONTINUES...WITH
MOST AUTOMATED AIRPORT SITES HITTING 100 DEGREES OR HIGHER. MADISON
AND MILWAUKEE REACHED 103 EACH...WITH LAKE BREEZE AT MILWAUKEE
LIKELY ENDING TEMPERATURE CLIMB THERE...MISSING ALL TIME HIGH OF 105
BY 2 DEGREES. MADISON MAY CLIMB ANOTHER DEGREE OR TWO...BUT SHOULD
ALSO FALL SHORT OF ALL TIME HIGH OF 107. HEAT INDEX VALUES GENERALLY
100 TO 110 WITH DEW POINTS MIXING OUT AGAIN.
ADDED ISOLATED THUNDERSTORMS TO THE FAR SOUTHEAST COUNTIES UNTIL 00Z
FRIDAY...AS A FEW SHOWERS HAVE POPPED UP IN SOUTH CENTRAL KENOSHA
COUNTY. THIS LIKELY A RESULT OF MOISTURE CONVERGENCE IN LOW LEVELS
WITH SOME WARM AIR ADVECTION...AND CONVECTIVE TEMPERATURES BEING
REACHED. RAP SOUNDING FROM KENOSHA SHOWING MEAN LAYER CAPES OF 600
J/KG WITH UNDER 25 KNOTS OF DEEP LAYER SHEAR. LAKE BREEZE BOUNDARY
THERE MAY ALSO HELP WITH LIFT.
WEAK FRONT WITH CUMULUS LINE TO THE NORTHWEST WILL SHIFT INTO THE
NORTHWEST PARTS OF THE AREA LATE THIS AFTERNOON OR EARLY THIS
EVENING...THEN STALL OVER THE AREA LATER TONIGHT. NOT ENOUGH DEEP
LIFT TO MENTION POPS WITH THIS FEATURE...GIVEN STRONG UPPER RIDGE IN
PLACE. LOWS TONIGHT TO REMAIN VERY WARM...IN THE MID TO UPPER 70S IN
MOST AREAS PER 925MB TEMPERATURES FROM NAM.
FRONT TRIES TO PUSH BACK NORTHEAST AS A WARM FRONT FRIDAY...BUT GETS
HUNG UP IN THE SOUTHEAST COUNTIES AS LIGHT ONSHORE WINDS HOLD IN
THAT AREA. KEPT DRY FORECAST GOING WITH LACK OF DEEP LIFT WITH
FRONT. TEMPERATURES ONCE AGAIN WILL HIT 100 OR A BIT HIGHER ACROSS
THE SOUTHWEST HALF OF THE AREA...INCLUDING MADISON...WITH COOLER 90S
ACROSS THE REST OF THE AREA WITHIN LIGHT ONSHORE FLOW. HEAT INDEX
VALUES WILL BE 95 TO 105 IN SOUTHEAST WISCONSIN...TO 100 TO 110 IN
SOUTH CENTRAL WISCONSIN. KEPT EXCESSIVE HEAT WARNINGS GOING FOR
ENTIRE AREA UNTIL 10 PM FRIDAY.
FRIDAY NIGHT THROUGH SUNDAY...FORECAST CONFIDENCE...MEDIUM.
THE COLD FRONT OVER NORTHERN WISCONSIN WILL SLOWLY APPROACH THE
FORECAST AREA FRIDAY NIGHT. THIS COLD FRONT COULD VERY WELL BE DRY
AS IT CROSSES SOUTHERN WISCONSIN...UNFORTUNATELY. THE NAM BRINGS
THE FRONT ACROSS DRY...THE GFS IS CHARACTERISTICALLY WET...AND THE
ECMWF IS PRETTY MUCH DRY. THE UPPER LEVEL DYNAMICS DO NOT REALLY
SUPPORT PRECIP WITH THIS FRONT. THE 850MB LOW LEVEL JET LEANS OVER
ACROSS CENTRAL WI TO BECOME WESTERLY AND WEAKEN AS THE FRONT
APPROACHES FRI NIGHT INTO SAT. THE STRONGEST 500MB SHORTWAVE SHIFTS TO
THE EAST OF WI AS THE FRONT GETS HERE. THE RIGHT ENTRANCE REGION OF
THE UPPER JET MAY PROVIDE SOME WEAK LIFT ALONG THE FRONT...AND THERE
MAY BE A WEAK RIPPLE IN THE 500MB FLOW THAT IS NOT REALLY APPARENT
IN THE MODELS AT THIS TIME. PREFER THE DRY NAM FRONTAL PASSAGE BUT
KEPT IN THE 25 TO 30 PERCENT POPS JUST IN CASE.
THE NAM IS STILL THE FASTEST WITH PUSHING THE FRONT DOWN TO THE IL
BORDER...SO TOOK A MODEL BLEND FOR TIMING...WITH THE SURFACE WINDS
CHANGING TO NORTH AROUND 18Z. THE SLOWER ECMWF HANGS ON TO A SMALL
CHANCE FOR TSTORMS ALONG THE 850MB BAROCLINIC ZONE THROUGH
SUNDAY...BUT KEPT THE FORECAST DRY FOR THIS PERIOD.
IT WILL STILL BE HOT ACROSS SOUTHERN WI AHEAD OF THIS FRONT WITH
925MB HANGING AROUND 31C. IF THERE IS PRECIP ALONG THE FRONT...THEN
CLOUDS WOULD GET IN THE WAY OF MAX HEATING. WENT WITH HIGHS IN THE
LOWER 90S ALONG THE IL BORDER...WITH 80S ELSEWHERE ON SAT. WILL KEEP
THE EXCESSIVE HEAT WARNING INTACT INTO THE EVENING HOURS AT THIS
POINT.
COLDEST 925MB AND 850MB TEMPS WILL BE OVER WI SAT NIGHT...WITH 925MB
TEMPS REBOUNDING UP TO AROUND 23C ON SUN. THIS COOLER TEMP PATTERN
WILL STICK AROUND UNTIL AT LEAST MID WEEK.
.LONG TERM...
MONDAY THROUGH THURSDAY...FORECAST CONFIDENCE...MEDIUM.
IF WE DO NOT GET PRECIP WITH THE FRONT SAT...IT LOOKS LIKE IT WILL
BE DRY THROUGH NEXT WEEK. THERE IS AN OUTSIDE CHANCE FOR PRECIP WITH
AN UPPER TROUGH PASSING THROUGH ON WED...BUT ONLY THE WET GFS SHOWS
THAT CHANCE...THEREFORE LEFT IT OUT OF FORECAST.
925MB TEMPS REBOUNDING UP TO AROUND 23C ON SUN...SO HIGHS IN THE 80S
EXPECTED THROUGH THE PERIOD...MAYBE WITH SOME UPPER 70S NEAR THE
LAKE. THIS COOLER TEMP PATTERN WILL STICK AROUND UNTIL AT LEAST MID
WEEK WITH HIGH PRESSURE OVERHEAD.
&&
.AVIATION/00Z TAFS/...
VFR CONDITIONS EXPECTED THROUGH FRIDAY ACROSS TAF SITES. WEST WINDS
MAY GUST UP TO 18 KNOTS AT TIMES THROUGH THE LATE AFTERNOON...WITH
MIXING OF LOW LEVELS FROM DAYTIME HEATING. SOUTHEASTERLY LAKE BREEZE
SHOULD CONTINUE AT MILWAUKEE UNTIL SUNSET...BUT REMAIN EAST OF
KENOSHA AND WAUKESHA. ISOLATED SHOWERS OR THUNDERSTORMS MAY AFFECT
KENOSHA...BUT CONFIDENCE TOO LOW TO INCLUDE IN TAF. SCATTERED
DIURNAL CUMULUS AT 8000 FEET AGL TO LINGER UNTIL SUNSET.
WEAK COLD FRONT WILL SLIDE SOUTHEAST THROUGH THE AREA THIS
EVENING...WITH WINDS VEERING NORTH TO NORTHEAST BEHIND IT. THEY MAY
BECOME LIGHT AND VARIABLE FOR A TIME LATER TONIGHT. WINDS VEER SOUTH
TO SOUTHWEST AT MADISON ON FRIDAY...SLOWLY INCREASING IN MAGNITUDE.
EASTERN SITES SHOULD SEE LIGHT NORTHEAST WINDS VEER SOUTHEAST DURING
THE DAY.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...EXCESSIVE HEAT WARNING UNTIL 10 PM CDT FRIDAY FOR WIZ046-047-051-
052-056>060-062>072.
LM...NONE.
&&
$$
TONIGHT/FRIDAY AND AVIATION/MARINE...WOOD
FRIDAY NIGHT THROUGH THURSDAY...MRC