Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/12/12
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1058 AM MDT SUN JUN 10 2012
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 323 AM MDT SUN JUN 10 2012
THE COLD FRONT REACHED ASPEN AND MONTROSE AROUND 2 AM BASED ON A
WIND SHIFT TO THE NORTH AND NORTHWEST...AND EXTENDED BACK ACROSS SE
UT TO ABOUT PAGE AZ. LATEST HI-RESOLUTION RAP AND HRRR MODELS SHOWED
THE FRONT BECOMING MORE DIFFUSE WITH ITS SOUTHEASTWARD PROGRESS
SLOWING AS IT ENCOUNTERS THE SAN JUAN MTNS AND ITS UPPER SUPPORT
WANES...BUT STILL CAPABLE OF GENERATING SOME GUSTY WINDS AT TIMES.
THE MAIN UPPER TROUGH AXIS MOVES ACROSS THE FORECAST AREA TODAY AS
THE PARENT UPPER LOW LIFTS INTO SOUTH-CENTRAL CANADA. TRAILING
ENERGY WILL SWEEP ACROSS NE UT/NW CO THIS AFTERNOON BUT THE AIR WILL
BE TOO DRY TO SUPPORT ANY PRECIPITATION...OR EVEN MUCH CLOUDINESS.
TEMPS WILL BE NOTICEABLY COOLER TODAY. WINDS WILL CONTINUE TO HAVE A
GUSTY CHARACTERISTIC BUT NOT NEARLY AS STRONG AS ON SATURDAY. LOW
AFTERNOON HUMIDITIES WILL PERSIST.
A COOL NIGHT IS IN STORE TONIGHT UNDER CLEAR SKIES. PARTS OF
NORTHWEST CO AS WELL AS MANY HIGH MTN VALLEYS COULD SEE FREEZING
TEMPS. MOS GUIDANCE SHOWED LOWS DIPPING BELOW 32F AT CRAIG...
MEEKER...EAGLE AND GUNNISON WHERE FOLKS WITH COLD-SENSITIVE PLANTS
SHOULD MONITOR FUTURE TEMPERATURE FORECASTS CLOSELY.
TEMPS SHOULD WARM FAIRLY QUICKLY UNDER SUNSHINE MONDAY. A WEAK WAVE
CROSSES THE FOUR CORNERS MONDAY WITH MODELS HINTING AT A FEW SHOWERS
OR STORMS OVER THE SAN JUAN MTNS AND UP THE CONTINENTAL DIVIDE.
BUT...BELIEVE THE WESTERLY FLOW WILL BE TOO DRY FOR THE SHORTWAVE TO
GENERATE ANY PRECIP...AND THE LOW-LEVEL E-SE UPSLOPE FLOW ON THE
EASTERN SLOPE TOO WEAK TO PUSH ENOUGH MOISTURE WEST OF THE DIVIDE.
THUS...WILL KEEP THE MENTION OF ANY PRECIP OUT OF THE FORECAST FOR
MONDAY AFTERNOON.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 323 AM MDT SUN JUN 10 2012
CLEAR SKIES MONDAY NIGHT BUT NOT AS COOL AS THE AIRMASS CONTINUES TO
MODIFY. ANOTHER WEAK WAVE PASSES TUESDAY AFTERNOON. MODELS AGAIN
HINT AT A FEW AFTERNOON SHOWERS/STORMS ALONG THE CONTINENTAL
DIVIDE...BUT WITH DRY WESTERLY FLOW STILL IN PLACE WILL CONTINUE
TO LEAVE OUT ANY MENTION OF PRECIP.
FLOW ALOFT BEGINS TO BUCKLE THE LAST HALF OF THE WEEK AS THE NEXT
PACIFIC TROUGH MOVES INLAND. MODELS KEEP THE MAIN STORM TRACK ALONG
THE USA/CANADA BORDER BUT DO SHOW...TO VARYING DEGREES...TROUGHING
MOVING INTO THE GREAT BASIN AND ACROSS OUR FORECAST AREA LATE IN THE
WEEK. MOISTURE CONTINUES TO LOOK LIMITED...SO A DRY FORECAST
WEDNESDAY THROUGH FRIDAY...THEN ISOLATED THUNDERSTORMS POSSIBLE OVER
THE NORTHERN MTNS ON SATURDAY. TEMPERATURES WILL RUN NEAR TO ABOVE
NORMAL WEDNESDAY THROUGH SATURDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1055 AM MDT SUN JUN 10 2012
DRY WEST NORTHWEST FLOW ALOFT WILL KEEP VFR CONDITIONS IN PLACE
THROUGH 18Z MONDAY. LOCALLY GUSTY WINDS TO 25 KTS CAN BE EXPECTED
THIS AFTERNOON AND EARLY EVENING...MAINLY OVER THE HIGHER RIDGES.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
SHORT TERM...JAD
LONG TERM...JAD
AVIATION...JDC
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
323 AM MDT SUN JUN 10 2012
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 323 AM MDT SUN JUN 10 2012
THE COLD FRONT REACHED ASPEN AND MONTROSE AROUND 2 AM BASED ON A
WIND SHIFT TO THE NORTH AND NORTHWEST...AND EXTENDED BACK ACROSS SE
UT TO ABOUT PAGE AZ. LATEST HI-RESOLUTION RAP AND HRRR MODELS SHOWED
THE FRONT BECOMING MORE DIFFUSE WITH ITS SOUTHEASTWARD PROGRESS
SLOWING AS IT ENCOUNTERS THE SAN JUAN MTNS AND ITS UPPER SUPPORT
WANES...BUT STILL CAPABLE OF GENERATING SOME GUSTY WINDS AT TIMES.
THE MAIN UPPER TROUGH AXIS MOVES ACROSS THE FORECAST AREA TODAY AS
THE PARENT UPPER LOW LIFTS INTO SOUTH-CENTRAL CANADA. TRAILING
ENERGY WILL SWEEP ACROSS NE UT/NW CO THIS AFTERNOON BUT THE AIR WILL
BE TOO DRY TO SUPPORT ANY PRECIPITATION...OR EVEN MUCH CLOUDINESS.
TEMPS WILL BE NOTICEABLY COOLER TODAY. WINDS WILL CONTINUE TO HAVE A
GUSTY CHARACTERISTIC BUT NOT NEARLY AS STRONG AS ON SATURDAY. LOW
AFTERNOON HUMIDITIES WILL PERSIST.
A COOL NIGHT IS IN STORE TONIGHT UNDER CLEAR SKIES. PARTS OF
NORTHWEST CO AS WELL AS MANY HIGH MTN VALLEYS COULD SEE FREEZING
TEMPS. MOS GUIDANCE SHOWED LOWS DIPPING BELOW 32F AT CRAIG...
MEEKER...EAGLE AND GUNNISON WHERE FOLKS WITH COLD-SENSITIVE PLANTS
SHOULD MONITOR FUTURE TEMPERATURE FORECASTS CLOSELY.
TEMPS SHOULD WARM FAIRLY QUICKLY UNDER SUNSHINE MONDAY. A WEAK WAVE
CROSSES THE FOUR CORNERS MONDAY WITH MODELS HINTING AT A FEW SHOWERS
OR STORMS OVER THE SAN JUAN MTNS AND UP THE CONTINENTAL DIVIDE.
BUT...BELIEVE THE WESTERLY FLOW WILL BE TOO DRY FOR THE SHORTWAVE TO
GENERATE ANY PRECIP...AND THE LOW-LEVEL E-SE UPSLOPE FLOW ON THE
EASTERN SLOPE TOO WEAK TO PUSH ENOUGH MOISTURE WEST OF THE DIVIDE.
THUS...WILL KEEP THE MENTION OF ANY PRECIP OUT OF THE FORECAST FOR
MONDAY AFTERNOON.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 323 AM MDT SUN JUN 10 2012
CLEAR SKIES MONDAY NIGHT BUT NOT AS COOL AS THE AIRMASS CONTINUES TO
MODIFY. ANOTHER WEAK WAVE PASSES TUESDAY AFTERNOON. MODELS AGAIN
HINT AT A FEW AFTERNOON SHOWERS/STORMS ALONG THE CONTINENTAL
DIVIDE...BUT WITH DRY WESTERLY FLOW STILL IN PLACE WILL CONTINUE
TO LEAVE OUT ANY MENTION OF PRECIP.
FLOW ALOFT BEGINS TO BUCKLE THE LAST HALF OF THE WEEK AS THE NEXT
PACIFIC TROUGH MOVES INLAND. MODELS KEEP THE MAIN STORM TRACK ALONG
THE USA/CANADA BORDER BUT DO SHOW...TO VARYING DEGREES...TROUGHING
MOVING INTO THE GREAT BASIN AND ACROSS OUR FORECAST AREA LATE IN THE
WEEK. MOISTURE CONTINUES TO LOOK LIMITED...SO A DRY FORECAST
WEDNESDAY THROUGH FRIDAY...THEN ISOLATED THUNDERSTORMS POSSIBLE OVER
THE NORTHERN MTNS ON SATURDAY. TEMPERATURES WILL RUN NEAR TO ABOVE
NORMAL WEDNESDAY THROUGH SATURDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 323 AM MDT SUN JUN 10 2012
VFR CONDITIONS EXPECTED AT ALL TAF SITES. GUSTY SURFACE WINDS AT
TIMES TODAY.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
SHORT TERM...JAD
LONG TERM...JAD
AVIATION...JAD
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
925 PM EDT MON JUN 11 2012
.SYNOPSIS...
HIGH PRESSURE OFF THE EAST COAST WILL GRADUALLY WEAKEN ITS GRIP ON
OUR WEATHER OVERNIGHT AS A STRONG COLD FRONT APPROACHES FROM THE
WEST. LOW PRESSURE IS EXPECTED TO FORM ALONG THIS FRONT AS IT
SLOWLY CROSSES THE REGION TUESDAY AND WEDNESDAY. HIGH PRESSURE
SHOULD THEN DOMINATE THE WEATHER OVER THE EASTERN SEABOARD THROUGH
THE UPCOMING WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
THE LAST OF THE MAINLY DIURNALLY DRIVEN SHOWERS ARE DYING OFF
ACROSS THE LEHIGH VALLEY AND DELAWARE VALLEY THIS EVENING. AFTER
THE SHOWER DISSIPATE...THERE IS NOT MUCH IN THE LOCAL AREA TO TAKE
ADVANTAGE OF THE LINGERING INSTABILITY FOR MORE ACTIVITY THROUGH
THE LATE EVENING HOURS. THE LARGER AREA OF SHOWERS OVER CENTRAL
VIRGINIA IS STILL SEVERAL HOURS OFF...AND SHOULD CLIP THE WESTERN
LEHIGH VALLEY AFTER 0800 UTC. THIS TREND IS SUPPORTED BY THE
LATEST HRRR RUN...WHICH KEEPS MOST OF THE SHOWERS WEST OF THE
LEHIGH VALLEY UNTIL JUST BEFORE DAYBREAK.
0000 UTC SOUNDINGS SHOW THAT THE INSTABILITY IS JUST ABOUT
GONE...AND BASED ON THIS THE THUNDER WAS REMOVED FROM JUST ABOUT
ALL AREAS OVERNIGHT. THE ONLY PLACE THAT COULD SEE SOME THUNDER
MIGHT BE THE LEHIGH VALLEY LATE TONIGHT.
LOW CLOUDS ARE FORMING IN PLACE ACROSS THE WESTERN HALF OF THE
AREA (WHERE THE LOW CLOUDS BROKE LATE THIS AFTERNOON)...BUT HAVE
YET TO TAKE HOLD OVER MUCH OF THE NEW JERSEY COAST. THE COOLING OF
THE BOUNDARY LAYER AND THE SOUTHEAST FLOW SHOULD ALLOW THE REST OF
THE AREA TO SEE THE LOW CLOUDS DEVELOP. FOR THE MOST PART...TEMPERATURES
PROBABLY DO NOT CHANGE MUCH...AS THE BOUNDARY LAYER DEW POINTS ARE
SLOWLY CREEPING UP. BASED ON THE ABOVE...LOWS WERE EDGED UP IN
MOST PLACES FOR THE OVERNIGHT.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
THE REAL ACTION BEGINS ON TUESDAY AS A VAST TROPICAL MOISTURE PLUME
RESIDES ACROSS THE REGION. PWATS WILL CLIMB TO NEAR 2 INCHES, IF NOT
ABOVE, IN MOST PLACES. THIS WILL ALLOW ANY CONVECTION THAT FIRES UP
TOMORROW TO TAP INTO THIS MOISTURE AND PRODUCE LOCALIZED
INUNDATIONS. MODELS OVER THE PAST COUPLE OF RUNS HAVE BACKED OFF A
BIT ON THE QPF WE COULD SEE TOMORROW BUT STILL POINTS TO AREAS
ACROSS OR NORTH AND WESTERN ZONES AS SEEING THE MOST...UPWARDS OF 1.5
INCHES ARE POSSIBLE. NO FLOOD WATCH HAS BEEN ISSUED AS WE CONTINUE
TO MENTION THE POSSIBILITY OF URBAN AND SMALL STREAM FLOODING IN OUR
HWO AND THE HYDROLOGY SECTION BELOW.
FOR THE MOST PART THE HEAVIEST SHOWERS WILL MOVE THROUGH DURING THE
AFTERNOON AND EARLY EVENING HOURS AS THIS IS WHEN WE HAVE TO THE
BEST CHANCE TO SEE ANY UPRIGHT CONVECTION. MODELS ARE SHOWING NEARLY
1000J/KG OF MLCAPE ACROSS THE AREA SO IT CAN BE SAID THAT ANY BREAKS
IN THE CLOUDS TOMORROW AFTERNOON COULD PROVIDE ENOUGH HEATING TO
BEGIN THE PARCEL LIFTING PROCESS COUPLED WITH PASSING MID-LEVEL
SHORTWAVES OVERHEAD.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
THE COLD FRONT WITH A LOW PRESSURE SYSTEM RIDING ALONG IT SHOULD MOVE
OFF THE COAST LATE TUESDAY NIGHT. HEAVY RAIN SHOULD END FROM WEST
TO EAST BY WEDNESDAY MORNING, AND ANY FLASH FLOODING THREAT SHOULD
END WITH IT (SEE HYDROLOGY SECTION BELOW). IMPROVING CONDITIONS CAN BE
EXPECTED THEREAFTER AS HIGH PRESSURE FROM THE GREAT LAKES AREA
BUILDS EAST AND NORTH. HOWEVER, A BOUNDARY MAY PERSIST OVER THE
EASTERN SEABOARD THROUGH THE WEEKEND AS AN UPPER LEVEL CUT-OFF LOW
OVER THE ATLANTIC RETROGRADE WESTWARD. A CHC/SLGT CHC OF SHOWERS
HAS BEEN PLACED IN THE FCST THROUGH SUNDAY AS A RESULT...MAINLY
DURING THE DAYTIME HOURS. SLIGHTLY COOLER THAN NORMAL TEMPERATURES
ARE POSSIBLE DURING THE BEGINNING OF THE PERIOD DUE TO AN EASTERLY
FLOW...BUT A WARM-UP IS POSSIBLE TOWARD THE BEGINNING OF NEXT WEEK
AS UPPER LEVEL RIDGING DEVELOPS OVER THE EASTERN U.S.
&&
.AVIATION /01Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
A FAIRLY NARROW STRIP OF MVFR CEILINGS STRETCH FROM SOUTHEAST NEW
JERSEY INTO THE KPHL AND KILG...WITH GENERALLY MVFR CONDITIONS ON
EITHER SIDE OF THE STRIP. THE MARINE INVERSION IN PLACE WILL LOWER
AFTER SUNSET...AND ALL LOCATIONS SHOULD HAVE MVFR CEILINGS BY 0500
UTC.
THE SOUTHEAST FLOW SHOULD ALLOW THE INVERSION TO DROP EVEN MORE
LATE TONIGHT...AND IFR CEILINGS SHOULD BE COMMON ACROSS THE REGION
AFTER 0900 OR 1000 UTC. MODEL SOUNDINGS SHOW THE POTENTIAL FOR
CEILINGS TO GET BACK TO MVFR AFTER 1400 UTC...AS HEATING HELPS LIFT
THE CLOUD BASES. IN FACT...A SHORT PERIOD OF VFR CONDITIONS IS
POSSIBLE CENTERED BETWEEN 1500 AND 1800 UTC FOR THE KPHL METRO
AIRPORTS...BUT CONFIDENCE IN NOT HIGH ENOUGH TO INCLUDE THIS NOW.
AS RAIN MOVES INTO THE REGION FROM THE SOUTH AND WEST...IFR CEILINGS
SHOULD REDEVELOP BETWEEN 2000 UTC AND 2200 UTC. THUNDERSTORMS ARE
POSSIBLE...BUT LEFT OUT OF THE FORECAST FOR NOW AS THEY SHOULD BE
FAIRLY SCATTERED. IN ADDITION...AN APPROACHING 40 KNOT LOW LEVEL JET
COULD PRODUCE LOW LEVEL WIND SHEAR...BUT THIS IS EXPECTED AFTER 0000
UTC WEDNESDAY.
OUTLOOK...
TUESDAY NIGHT...IFR TO MVFR CONDITIONS IN SHRA/TSRA AND
ASSOCIATED CLOUDS COVER AS THE FRONTAL SYSTEM MOVES SLOWLY OFF THE
COAST. GUSTY SOUTHEAST WINDS WILL SHIFT TO THE NORTHEAST DURING
THE LATE OVERNIGHT HOURS.
WEDNESDAY...MVFR CONDITIONS EXPECTED AS SHRA ACTIVITY DIMINISHES.
GUSTY NORTHEAST WINDS BECOMING EAST AND DIMINISHING AS THE DAY WEARS
ON.
WEDNESDAY NIGHT THROUGH SATURDAY...GENERALLY VFR CONDITIONS EXPECTED
BUT A FEW SHOWERS CAN`T BE RULED OUT DURING THE AFTERNOON AND EARLY
EVENING HOURS.
&&
.MARINE...
THE WINDS FUNNELING UP THE DELAWARE BAY HAVE NOT YET BACK OFF...AS
SJSN4 IS STILL GUSTING NEAR 30 KNOTS. WINDS ON THE LOWER BAYS HAVE
BACKED OFF A BIT...BUT BASED ON THE SJSN4 OBSERVATION THE SMALL
CRAFT ADVISORY HAS BEEN EXTENDED UNTIL 100 AM. IT IS LIKELY THAT
WINDS WILL DROP BELOW SMALL CRAFT LEVELS BEFORE THEN...BUT COULD
HANG ON ACROSS THE UPPER BAY THROUGH AT LEAST MIDNIGHT.
SEAS ON THE SOUTHERN OCEAN WATERS CONTINUE TO SLOWLY TICK UPWARD
DUE PRIMARILY TO THE SOUTHEAST SWELL. THE LATEST WNAWAVE RUN TRIES
TO BRING SEAS AT 44009 TO 5 FEET BEFORE MORNING. HOWEVER...THE
MODEL OUTPUT IS RUNNING HIGH...AS IT TENDS TO DO IN A SOUTHEAST
FLOW. SEAS WILL BE HELD JUST BELOW SMALL CRAFT LEVELS ON THE OCEAN
OVERNIGHT.
WITH WINDS STILL OUT THE EAST-SOUTHEAST WE WILL BEGIN TO SEAS RISE
THROUGH TUESDAY. STILL NOT SURE IF SEAS WILL BUILD ENOUGH TO SEE
SMALL CRAFT ADVISORY LEVELS, ESPECIALLY ACROSS OUR SOUTHERN WATERS
WHERE SEAS ARE LESS THAN 2 FEET. WE WOULD NEED THE WINDS TO GO
ALMOST DIRECTLY SOUTH TO EXPERIENCE ANY GREAT RISES IN THE SEAS.
WINDS ALSO LOOK TO REMAIN BELOW ADVISORY LEVELS WITH A FEW GUSTS
AROUND 20 KNOTS TUESDAY AFTERNOON. AS FAR AS IMPACTING WEATHER GOES,
A COLD FRONT WILL SWEEP THROUGH BY LATE TOMORROW EVENING. THIS FRONT
WILL PRODUCE HEAVY RAIN AND THUNDERSTORMS DURING THROUGH TUESDAY
NIGHT.
OUTLOOK...
NJ/DE ATLC WATERS: NEAR SCA CONDITIONS POSSIBLE THROUGH
FRIDAY...MAINLY DUE TO HAZARDOUS SEAS FROM A PERSISTENT NE FLOW.
DEL BAY: MOSTLY SUB SCA THROUGH THE PERIOD EXCEPT POSSIBLY IN A NE
FLOW G20-25KT THURSDAY.
&&
.HYDROLOGY...
THUNDERSTORMS ASSOCIATED WITH A SLOW MOVING COLD FRONT COULD PRODUCE
AN INCH OR MORE OF RAIN IN AN HOUR LATE TUESDAY. WHILE THERE IS
STILL SOME DISPARAGE WITH VARIOUS MODELS...A WIDESPREAD 0.5 TO 1.5
INCH EVENT IS STILL EXPECTED WITH ISOLATED 3 INCH AMTS
POSSIBLE...MOST OF THIS IN A 6 TO 9 HR PERIOD TUE AFTN/NIGHT. E
PA/NNJ AND THE URBAN CENTERS ARE MOST VULNERABLE TO 3 HR RAINFALL OF
2+ INCHES. BECAUSE OF UNCERTAINTY WITH AMOUNTS AND LOCATION OF THE
HEAVIEST RAIN...A FLASH FLOOD WATCH WILL NOT BE ISSUED AT THIS TIME.
HOWEVER..A MENTION OF POSSIBLE FLASH FLOODING WILL BE MAINTAINED IN
THE HWO.
NO MAIN STEM RIVER FLOODING IS EXPECTED FROM THIS EVENT.
&&
.RIP CURRENTS...
THE COMBINATION OF SOUTHEAST WINDS NEAR 15 MPH AND A 3 TO 5 FOOT
SOUTHEAST SWELL AROUND 6 SECONDS WILL COMBINE TO PRODUCE A MODERATE
RISK OF RIP CURRENT ON THE NEW JERSEY BEACHES. LOCAL GUIDANCE
SUGGESTS THAT THE RIP CURRENT RISK FOR THE DELAWARE COAST WILL
REMAIN LOW.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 AM EDT TUESDAY FOR ANZ430-431.
&&
$$
SYNOPSIS...MIKETTA
NEAR TERM...HAYES/HEAVENER
SHORT TERM...HEAVENER
LONG TERM...KLINE/MIKETTA
AVIATION...HAYES/MIKETTA
MARINE...HAYES/HEAVENER
HYDROLOGY...MIKETTA
RIP CURRENTS...HAYES
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
956 PM CDT MON JUN 11 2012
.DISCUSSION...
903 PM CDT
UPDATE FOR REST OF TONIGHT...LAST HOPES FOR EVEN A STRAY SHOWER
OR THUNDERSHOWER FOR THE EASTERN PORTION OF THE LOCAL FORECAST
AREA IS QUICKLY DRYING UP...PUN INTENDED...AS THE PRE-FRONTAL
TROUGH HAS SHIFTED THE AXIS OF HIGHEST DEW POINTS AND GREATEST
POTENTIAL INSTABILITY E TO SW LOWER MI AND N CENTRAL IN. THE TRUE
COLD FRONT IS WELL DELINEATED FROM EXTREME SE WI SOUTHWESTWARD TO
W CENTRAL IL BY BOTH A WIND SHIFT FROM SW TO W AND NW...AS WELL AS
A DEW POINTS FALLING OFF TO THE UPPER AND MID 50S.
CURRENT REMAINING SLIGHT CHANCE POP NUMBERS FOR THE SE PORTION OF
THE FA WILL BE DROPPING OUT WITHIN AN HOUR OR TWO.
WITH CHANCES OF RAIN MINIMAL AT BEST THROUGH EARLY NEXT WEEK AT
LEAST...AND NEAR ZERO CHANCES THROUGH THE REST OF THIS WEEK
INCREASINGLY SERIOUS SOIL MOISTURE DEFICITS WILL LIKELY BE
CAUSING EVEN GREATER STRESS ON TREES AND CROPS.
TRS
//PREV DISCUSSION...
320 PM CDT
THE FORECAST CONCERNS ARE VERY MINIMAL THROUGH THE REST OF THE
WEEK WITH A CONTINUED DRY PATTERN. WILL BE MONITORING FOR A FEW
STORMS LATE THIS AFTERNOON INTO EARLY EVENING...OTHERWISE THAT MAY
WILL LIKELY BE ALL THAT IS ON THE SCOPE FOR QUITE A WHILE.
ISOLATED SHOWERS WITH A FEW STORMS REDEVELOPING OVER COOK COUNTY
AND SOUTH ALONG THE IL/IN STATE LINE...WHICH IS ALONG AND JUST
AHEAD OF A WEAK CONVERGENT AXIS AND APPARENT SHORT WAVE SEEN ON
SATELLITE. MID 80S TEMPERATURES AND UPPER 60S DEW POINTS ALONG AND
AHEAD OF THIS CORRIDOR HAS BUILT SURFACE BASED CAPE TO AROUND OR
SLIGHTLY OVER 2000 J/KG. THIS CONVECTION SHOULD LAST LONGER THAN
THE PREVIOUS ACTIVITY NEAR NOON BEING CLOSER TO THE SHORT WAVE
CENTER AND HAVING MORE INSTABILITY TO WORK WITH. UPPER LEVEL WIND
SHEAR LOOKS TO BE AROUND A MEAGER 20 KT PER PROFILER ANALYSIS. THE
BEHAVIOR OF THE STORM CORES IS LIKELY TO BE SOMEWHAT PULSY WITH
INSTABILITY IN THE DRIVERS SEAT...AND WITH LIMITED ATTENDANT SHEAR
IT LEAVES ONLY A VERY SMALL CHANCE FOR ANY TYPE OF SEVERE ACTIVITY.
THE SYSTEM UPPER TROUGH CENTER IS LOCATED ALONG THE MN/WESTERN
QUEBEC BORDER WITH PRIMARY HEIGHT FALLS...THE UPPER JET AXIS...AND
ASSOCIATED DEEPER ASCENT MOVING EAST FROM THERE. THIS FORCING HAS
AIDED SOME SHOWER DEVELOPMENT ALONG THE SURFACE COLD FRONT IN
WESTERN WI. THE COOL FRONT EXTENDS SOUTH FROM THERE WHERE IT WILL
MOVE INTO NW IL BY 4 PM AND EAST THROUGH THE FORECAST AREA THIS
EVE. THE WIND SHIFT IS GRADUAL FROM WEST SOUTHWEST TO WEST
NORTHWEST ALONG THE BOUNDARY...AND IT IS ACTUALLY AHEAD OF THE
STRONGEST MOISTURE CONVERGENCE. SO OVERALL CONVERGENCE IS LIMITED
AND FEEL THAT WILL BE THE CASE WITH ANY CONVECTION THAT WERE TO
TRIGGER ALONG IT...WHICH IS NOW APPEARING DOUBTFUL IN OUR AREA.
THE HRRR AND OTHER EXPLICIT CONVECTIVE MODELS AGREE IN THIS
LIMITED COVERAGE.
THE COOL FRONT WILL MOVE THROUGH THE AREA THIS EVENING AND IT
LOOKS LIKE THE BOUNDARY LAYER WILL STAY MIXED AS IT DOES
SUCH...WITH SOME GUSTS UP TO 20 MPH AS THE PRESSURE RISE AXIS
MOVES THROUGH. SUNNY AND DRY WEATHER WILL THEN ONCE AGAIN BE THE
STORY AS CANADIAN HIGH PRESSURE MOVES OVERHEAD TUESDAY NIGHT INTO
WEDNESDAY. THE REALLY ONLY WEATHER OF INTEREST FROM DAY TO DAY WILL
BE HOW LOW DEW POINTS WILL DROP DURING THE AFTERNOON MIXING...AND
TO WHAT DEGREE OF COOLING WILL THERE BE FROM THE LAKE. NORTHWEST
WINDS WILL BEGIN TO DECREASE TUESDAY AFTERNOON...POTENTIALLY
ALLOWING FOR A SLIGHT LAKE BREEZE INTO IL...BUT LIKELY INTO IN.
THIS MAY NOT DEVELOP UNTIL LATE AFTERNOON THOUGH...SO WIDESPREAD
HIGHS IN THE MID TO UPPER 70S ARE EXPECTED. UPSTREAM DEW POINTS
TODAY HAVE BEEN IN THE LOWER TO MID 40S ACROSS EASTERN SD. THIS
AND POSSIBLY EVEN LOWER SHOULD BE REALIZED DURING TUESDAY AFTERNOON
WITH PROJECTED MIXING TO 850 MB. THE AFTERNOON HUMIDITY WILL
REMAIN LOW...UNDER 25 PERCENT...ON WEDNESDAY AFTERNOON WITH THE
SYNOPTIC FLOW TURNING NORTHEAST AND THEN EAST.
INFLUENCE FROM THE LAKE WILL LIKELY CONTINUE TO MOVE INTO CHICAGO
DURING THE AFTERNOON ALL THE WAY THROUGH SATURDAY. THE UPPER LEVEL
HEIGHTS AND LOW-LEVEL THERMAL RIDGE BUILD MORE INTO THE AREA
THURSDAY NIGHT INTO SATURDAY. THE EC HAS SHOWN IN THE UPPER LEVEL
SW FLOW THAT SHORT WAVE ENERGY IS POSSIBLE WITHIN THIS AND MAY
DAMPEN THE RIDGE SLIGHTLY SATURDAY NIGHT INTO SUNDAY...AND HAVE A
SMALL CHANCE FOR POPS DURING PART OF THAT TIME. OTHERWISE...HAVE
COLLABORATED GOING DRIER THAN POPS AND DEW POINTS FROM GUIDANCE
BLENDS IN THE EXTENDED PER PERSISTENCE AND AN OVERALL STAGNANT
PATTERN.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 03Z...
* COLD FROPA THIS EVENING WITH WIND SHIFT FROM SW TO WNW 02-03Z.
* NORTHWEST WINDS TUES VEERING NORTHEAST LATE IN THE DAY.
RATZER
//DISCUSSION...UPDATED 00Z...
LOW PRESSURE PASSING WELL NORTH OF THE LOCAL FORECAST AREA EARLY
THIS EVENING. COLD FRONT TRAILING FROM THIS LOW WAS INTO WESTERN
IL AT 23Z...AND WILL CONTINUE TO PUSH EAST ACROSS THE TERMINALS
OVER THE NEXT FEW HOURS. WINDS HAVE SHIFTED TO 230-250 DEG AHEAD
OF THE FRONT IN THE WAKE OF A PRE-FRONTAL TROUGH WHICH MOVED
THROUGH EARLIER...AND WINDS ARE EXPECTED TO FURTHER SHIFT TO
290-310 DEG AFTER THE COLD FRONT MOVES THROUGH THIS EVENING. WINDS
ARE CURRENTLY SPORADICALLY GUSTING NEAR 20 KTS AHEAD OF THE
FRONT...AND ARE GUSTING INTO THE LOW-MID 20 KT RANGE BEHIND THE
FRONT WITH DEEPER MIXING OF BOUNDARY LAYER IN COOL ADVECTION. THUS
EXPECT SOME GUSTS TO CONTINUE AFTER FROPA THROUGH LATE EVENING
WITH 25-30 KTS NOTED WITHIN MIXED LAYER. SOME QUESTION EXISTS AS
TO HOW QUICKLY BOUNDARY LAYER COOLING WILL RESULT IN DECREASING
GUSTS...BUT SHOULD SEE AT LEAST SOME SPORADIC GUSTS ABOVE 20 KTS
FOR A COUPLE OF HOURS WITH PRESSURE RISES BEHIND THE FRONT.
HIGH PRESSURE BUILDS SOUTHEAST ACROSS THE REGION TUESDAY...WITH
NORTHWEST WINDS GUSTING INTO THE 15-20 KT RANGE DURING THE DAY.
WINDS WILL EVENTUALLY SHIFT NORTH-NORTHEAST LATE IN THE DAY.
AS FOR SMALL POTENTIAL FOR SHRA/TSRA UNTIL FROPA THIS EVENING...
SPC RAP ANALYSIS CONTINUES TO INDICATE INSTABILITY LINGERING AHEAD
OF COLD FRONT ACROSS NORTHERN IL. HOWEVER...WIND SHIFT ASSOCIATED
WITH EARLIER PRE-FRONTAL TROUGH PASSAGE IS RESULTING IN LITTLE
CONVERGENCE TO SUPPORT SUSTAINED CU DEVELOPMENT OR UPDRAFTS. THUS
WHILE THE PROBABILITY IS NOT ZERO THAT AN ISOLATED TSRA/SHRA COULD
DEVELOP AHEAD OF THE COLD FRONT THIS EVENING...IT IS VERY LOW AND
HAS NOT BEEN MENTIONED IN TAFS.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* HIGH CONFIDENCE IN FROPA TIMING AND WIND TRENDS THROUGH THIS
EVENING.
* HIGH CONFIDENCE IN VFR CONDITIONS AND NORTHWEST WINDS
TUES...MEDIUM CONFIDENCE IN TIMING OF SHIFT TO NORTHEAST LATE
TUES.
RATZER
//OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z...
WEDNESDAY THROUGH SUNDAY...VFR. SLIGHT CHC SHRA/TSRA WEST OF
TERMINALS SUNDAY.
RATZER
&&
.MARINE...
231 PM CDT
A LARGE LOW HAS MOVED INTO HUDSON BAY...WHILE HIGH PRESSURE SITS OFF
THE NEW ENGLAND COAST. THE UPPER LEVEL PRESSURE GRADIENT HAS
RELAXED...RESULTING IN SOUTH TO SOUTHWEST WINDS 15-25 KT ACROSS THE
LAKE THIS AFTERNOON. STRONGEST WINDS AROUND 25 KT WILL CONTINUE TO
BE OVER THE NORTHERN HALF OF THE LAKE WHICH IS CLOSER TO THE LOW AND
ITS TIGHT PRESSURE GRADIENT. THE LOWS COLD FRONT WILL SWEEP ACROSS
THE LAKE TONIGHT. WINDS WILL TURN OUT OF THE WEST AT 15 TO 25 KT
ACROSS THE LAKE BEHIND THE FRONT. HIGH PRESSURE MOVES IN BEHIND THE
FRONT TUESDAY NIGHT...WITH WINDS DIMINISHING AND BECOMING NORTHERLY
FOR A ON TUESDAY. THE LIGHT WINDS WILL CONTINUE TO VEER TO EASTERLY
AS THE HIGH MOVES OVER THE LAKE WEDNESDAY. WINDS TURN SOUTHEASTERLY
AS THE HIGH MAKES ITS WAY OVER NORTHERN QUEBEC ON THURSDAY.
ALTHOUGH THE CENTER OF THE HIGH MOVES OFF TO THE NORTHEAST...A LARGE
RIDGE WILL REMAIN OVER THE EASTERN THIRD OF THE US THROUGH THE
REMAINING PART OF THE FORECAST PERIOD. THIS PATTERN WILL RESULT IN
LIGHT WINDS VARYING BETWEEN EAST AND SOUTH.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
904 PM CDT MON JUN 11 2012
.DISCUSSION...
903 PM CDT
UPDATE FOR REST OF TONIGHT...LAST HOPES FOR EVEN A STRAY SHOWER
OR THUNDERSHOWER FOR THE EASTERN PORTION OF THE LOCAL FORECAST
AREA IS QUICKLY DRYING UP...PUN INTENDED...AS THE PRE-FRONTAL
TROUGH HAS SHIFTED THE AXIS OF HIGHEST DEW POINTS AND GREATEST
POTENTIAL INSTABILITY E TO SW LOWER MI AND N CENTRAL IN. THE TRUE
COLD FRONT IS WELL DELINEATED FROM EXTREME SE WI SOUTHWESTWARD TO
W CENTRAL IL BY BOTH A WIND SHIFT FROM SW TO W AND NW...AS WELL AS
A DEW POINTS FALLING OFF TO THE UPPER AND MID 50S.
CURRENT REMAINING SLIGHT CHANCE POP NUMBERS FOR THE SE PORTION OF
THE FA WILL BE DROPPING OUT WITHIN AN HOUR OR TWO.
WITH CHANCES OF RAIN MINIMAL AT BEST THROUGH EARLY NEXT WEEK AT
LEAST...AND NEAR ZERO CHANCES THROUGH THE REST OF THIS WEEK
INCREASINGLY SERIOUS SOIL MOISTURE DEFICITS WILL LIKELY BE
CAUSING EVEN GREATER STRESS ON TREES AND CROPS.
TRS
&&
.PREV DISCUSSION...
320 PM CDT
THE FORECAST CONCERNS ARE VERY MINIMAL THROUGH THE REST OF THE
WEEK WITH A CONTINUED DRY PATTERN. WILL BE MONITORING FOR A FEW
STORMS LATE THIS AFTERNOON INTO EARLY EVENING...OTHERWISE THAT MAY
WILL LIKELY BE ALL THAT IS ON THE SCOPE FOR QUITE A WHILE.
ISOLATED SHOWERS WITH A FEW STORMS REDEVELOPING OVER COOK COUNTY
AND SOUTH ALONG THE IL/IN STATE LINE...WHICH IS ALONG AND JUST
AHEAD OF A WEAK CONVERGENT AXIS AND APPARENT SHORT WAVE SEEN ON
SATELLITE. MID 80S TEMPERATURES AND UPPER 60S DEW POINTS ALONG AND
AHEAD OF THIS CORRIDOR HAS BUILT SURFACE BASED CAPE TO AROUND OR
SLIGHTLY OVER 2000 J/KG. THIS CONVECTION SHOULD LAST LONGER THAN
THE PREVIOUS ACTIVITY NEAR NOON BEING CLOSER TO THE SHORT WAVE
CENTER AND HAVING MORE INSTABILITY TO WORK WITH. UPPER LEVEL WIND
SHEAR LOOKS TO BE AROUND A MEAGER 20 KT PER PROFILER ANALYSIS. THE
BEHAVIOR OF THE STORM CORES IS LIKELY TO BE SOMEWHAT PULSY WITH
INSTABILITY IN THE DRIVERS SEAT...AND WITH LIMITED ATTENDANT SHEAR
IT LEAVES ONLY A VERY SMALL CHANCE FOR ANY TYPE OF SEVERE ACTIVITY.
THE SYSTEM UPPER TROUGH CENTER IS LOCATED ALONG THE MN/WESTERN
QUEBEC BORDER WITH PRIMARY HEIGHT FALLS...THE UPPER JET AXIS...AND
ASSOCIATED DEEPER ASCENT MOVING EAST FROM THERE. THIS FORCING HAS
AIDED SOME SHOWER DEVELOPMENT ALONG THE SURFACE COLD FRONT IN
WESTERN WI. THE COOL FRONT EXTENDS SOUTH FROM THERE WHERE IT WILL
MOVE INTO NW IL BY 4 PM AND EAST THROUGH THE FORECAST AREA THIS
EVE. THE WIND SHIFT IS GRADUAL FROM WEST SOUTHWEST TO WEST
NORTHWEST ALONG THE BOUNDARY...AND IT IS ACTUALLY AHEAD OF THE
STRONGEST MOISTURE CONVERGENCE. SO OVERALL CONVERGENCE IS LIMITED
AND FEEL THAT WILL BE THE CASE WITH ANY CONVECTION THAT WERE TO
TRIGGER ALONG IT...WHICH IS NOW APPEARING DOUBTFUL IN OUR AREA.
THE HRRR AND OTHER EXPLICIT CONVECTIVE MODELS AGREE IN THIS
LIMITED COVERAGE.
THE COOL FRONT WILL MOVE THROUGH THE AREA THIS EVENING AND IT
LOOKS LIKE THE BOUNDARY LAYER WILL STAY MIXED AS IT DOES
SUCH...WITH SOME GUSTS UP TO 20 MPH AS THE PRESSURE RISE AXIS
MOVES THROUGH. SUNNY AND DRY WEATHER WILL THEN ONCE AGAIN BE THE
STORY AS CANADIAN HIGH PRESSURE MOVES OVERHEAD TUESDAY NIGHT INTO
WEDNESDAY. THE REALLY ONLY WEATHER OF INTEREST FROM DAY TO DAY WILL
BE HOW LOW DEW POINTS WILL DROP DURING THE AFTERNOON MIXING...AND
TO WHAT DEGREE OF COOLING WILL THERE BE FROM THE LAKE. NORTHWEST
WINDS WILL BEGIN TO DECREASE TUESDAY AFTERNOON...POTENTIALLY
ALLOWING FOR A SLIGHT LAKE BREEZE INTO IL...BUT LIKELY INTO IN.
THIS MAY NOT DEVELOP UNTIL LATE AFTERNOON THOUGH...SO WIDESPREAD
HIGHS IN THE MID TO UPPER 70S ARE EXPECTED. UPSTREAM DEW POINTS
TODAY HAVE BEEN IN THE LOWER TO MID 40S ACROSS EASTERN SD. THIS
AND POSSIBLY EVEN LOWER SHOULD BE REALIZED DURING TUESDAY AFTERNOON
WITH PROJECTED MIXING TO 850 MB. THE AFTERNOON HUMIDITY WILL
REMAIN LOW...UNDER 25 PERCENT...ON WEDNESDAY AFTERNOON WITH THE
SYNOPTIC FLOW TURNING NORTHEAST AND THEN EAST.
INFLUENCE FROM THE LAKE WILL LIKELY CONTINUE TO MOVE INTO CHICAGO
DURING THE AFTERNOON ALL THE WAY THROUGH SATURDAY. THE UPPER LEVEL
HEIGHTS AND LOW-LEVEL THERMAL RIDGE BUILD MORE INTO THE AREA
THURSDAY NIGHT INTO SATURDAY. THE EC HAS SHOWN IN THE UPPER LEVEL
SW FLOW THAT SHORT WAVE ENERGY IS POSSIBLE WITHIN THIS AND MAY
DAMPEN THE RIDGE SLIGHTLY SATURDAY NIGHT INTO SUNDAY...AND HAVE A
SMALL CHANCE FOR POPS DURING PART OF THAT TIME. OTHERWISE...HAVE
COLLABORATED GOING DRIER THAN POPS AND DEW POINTS FROM GUIDANCE
BLENDS IN THE EXTENDED PER PERSISTENCE AND AN OVERALL STAGNANT
PATTERN.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* COLD FROPA THIS EVENING WITH WIND SHIFT FROM SW TO WNW 02-03Z.
* NORTHWEST WINDS TUES VEERING NORTHEAST LATE IN THE DAY.
* VERY LOW PROBABILITY SHRA/TSRA POTENTIAL PRIOR TO FROPA THIS
EVENING.
RATZER
//DISCUSSION...UPDATED 00Z...
LOW PRESSURE PASSING WELL NORTH OF THE LOCAL FORECAST AREA EARLY
THIS EVENING. COLD FRONT TRAILING FROM THIS LOW WAS INTO WESTERN
IL AT 23Z...AND WILL CONTINUE TO PUSH EAST ACROSS THE TERMINALS
OVER THE NEXT FEW HOURS. WINDS HAVE SHIFTED TO 230-250 DEG AHEAD
OF THE FRONT IN THE WAKE OF A PRE-FRONTAL TROUGH WHICH MOVED
THROUGH EARLIER...AND WINDS ARE EXPECTED TO FURTHER SHIFT TO
290-310 DEG AFTER THE COLD FRONT MOVES THROUGH THIS EVENING.
WINDS ARE CURRENTLY SPORADICALLY GUSTING NEAR 20 KTS AHEAD OF THE
FRONT...AND ARE GUSTING INTO THE LOW-MID 20 KT RANGE BEHIND THE
FRONT WITH DEEPER MIXING OF BOUNDARY LAYER IN COOL ADVECTION.
THUS EXPECT SOME GUSTS TO CONTINUE AFTER FROPA THROUGH LATE
EVENING WITH 25-30 KTS NOTED WITHIN MIXED LAYER. SOME QUESTION
EXISTS AS TO HOW QUICKLY BOUNDARY LAYER COOLING WILL RESULT IN
DECREASING GUSTS...BUT SHOULD SEE AT LEAST SOME SPORADIC GUSTS
ABOVE 20 KTS FOR A COUPLE OF HOURS WITH PRESSURE RISES BEHIND THE
FRONT.
HIGH PRESSURE BUILDS SOUTHEAST ACROSS THE REGION TUESDAY...WITH
NORTHWEST WINDS GUSTING INTO THE 15-20 KT RANGE DURING THE DAY.
WINDS WILL EVENTUALLY SHIFT NORTH-NORTHEAST LATE IN THE DAY.
AS FOR SMALL POTENTIAL FOR SHRA/TSRA UNTIL FROPA THIS EVENING...
SPC RAP ANALYSIS CONTINUES TO INDICATE INSTABILITY LINGERING AHEAD
OF COLD FRONT ACROSS NORTHERN IL. HOWEVER...WIND SHIFT ASSOCIATED
WITH EARLIER PRE-FRONTAL TROUGH PASSAGE IS RESULTING IN LITTLE
CONVERGENCE TO SUPPORT SUSTAINED CU DEVELOPMENT OR UPDRAFTS. THUS
WHILE THE PROBABILITY IS NOT ZERO THAT AN ISOLATED TSRA/SHRA COULD
DEVELOP AHEAD OF THE COLD FRONT THIS EVENING...IT IS VERY LOW AND
HAS NOT BEEN MENTIONED IN TAFS.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* MEDIUM-HIGH CONFIDENCE IN FROPA TIMING AND WIND TRENDS THROUGH
THIS EVENING.
* MEDIUM-HIGH CONFIDENCE IN NO ADDITIONAL SHRA/TSRA IMPACTING
TERMINALS THIS EVENING.
* HIGH CONFIDENCE IN VFR CONDITIONS AND NORTHWEST WINDS
TUES...MEDIUM CONFIDENCE IN TIMING OF SHIFT TO NORTHEAST LATE
TUES.
RATZER
//OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z...
WEDNESDAY THROUGH SUNDAY...VFR. SLIGHT CHC SHRA/TSRA WEST OF
TERMINALS SUNDAY.
RATZER
&&
.MARINE...
231 PM CDT
A LARGE LOW HAS MOVED INTO HUDSON BAY...WHILE HIGH PRESSURE SITS OFF
THE NEW ENGLAND COAST. THE UPPER LEVEL PRESSURE GRADIENT HAS
RELAXED...RESULTING IN SOUTH TO SOUTHWEST WINDS 15-25 KT ACROSS THE
LAKE THIS AFTERNOON. STRONGEST WINDS AROUND 25 KT WILL CONTINUE TO
BE OVER THE NORTHERN HALF OF THE LAKE WHICH IS CLOSER TO THE LOW AND
ITS TIGHT PRESSURE GRADIENT. THE LOWS COLD FRONT WILL SWEEP ACROSS
THE LAKE TONIGHT. WINDS WILL TURN OUT OF THE WEST AT 15 TO 25 KT
ACROSS THE LAKE BEHIND THE FRONT. HIGH PRESSURE MOVES IN BEHIND THE
FRONT TUESDAY NIGHT...WITH WINDS DIMINISHING AND BECOMING NORTHERLY
FOR A ON TUESDAY. THE LIGHT WINDS WILL CONTINUE TO VEER TO EASTERLY
AS THE HIGH MOVES OVER THE LAKE WEDNESDAY. WINDS TURN SOUTHEASTERLY
AS THE HIGH MAKES ITS WAY OVER NORTHERN QUEBEC ON THURSDAY.
ALTHOUGH THE CENTER OF THE HIGH MOVES OFF TO THE NORTHEAST...A LARGE
RIDGE WILL REMAIN OVER THE EASTERN THIRD OF THE US THROUGH THE
REMAINING PART OF THE FORECAST PERIOD. THIS PATTERN WILL RESULT IN
LIGHT WINDS VARYING BETWEEN EAST AND SOUTH.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
900 PM CDT MON JUN 11 2012
.DISCUSSION...
ISSUED 849 PM CDT MON JUN 11 2012
LATEST SURFACE ANALYSIS INDICATING THE COLD FRONT WAS LOCATED JUST
WEST OF PEORIA AND JACKSONVILLE WITH DEW POINTS SOME 15 TO 20 DEGREES
LOWER TO THE WEST OF THE FRONT EARLY THIS EVENING. EXTENSIVE CLOUD
COVER FROM THE CONVECTION WHICH OCCURRED OVER PARTS OF THE CENTRAL
AND SOUTHERN FORECAST AREA TODAY...AND LACK OF ANY SIGNIFICANT
LOW LEVEL CONVERGENCE ALONG THE FRONT HAS LED TO VERY LITTLE
REDEVELOPMENT OF STORMS THIS EVENING. THE BULK OF THE NEWLY DEVELOPED
CONVECTION HAS OCCURRED FURTHER TO THE NORTH AND EAST AND WAS MOVING
AWAY FROM OUR AREA. THE 00Z ILX SOUNDING INDICATING A FAIRLY WORKED
OVER ATMOSPHERE ACROSS CENTRAL ILLINOIS FROM THE CONVECTION OF EARLIER
TODAY WITH A SIGNIFICANT AMOUNT OF CONVECTIVE INHIBITION NOTED. THE
SLIGHT CHANCE/ISOLATED POPS HAVE BEEN REMOVED FROM THE GRIDS AND
OTHER THAN SOME MINOR TWEAKS TO THE EARLY EVENING HOURLY TEMPS...THE
REST OF THE FORECAST HAS A GOOD HANDLE ON THE OVERNIGHT TRENDS. THE
UPATED ZONE FORECAST WILL BE OUT BY 915 PM.
SMITH
&&
.AVIATION...
ISSUED 605 PM CDT MON JUN 11 2012
VFR CONDITIONS TO PREVAIL THRU TUESDAY. COLD FRONT WAS NOW PUSHING
INTO WEST CENTRAL ILLINOIS AND WILL CONTINUE TO SHIFT EAST ACRS THE
FORECAST AREA THIS EVENING. CLOUD COVER FROM MCS THAT SHIFTED THRU
SOUTHERN ILLINOIS AND WEAK LOW LEVEL CONVERGENCE ALONG FRONT WILL
KEEP PRECIP CHANCES MINIMAL THIS EVENING. FRONT SHOULD SHIFT EAST
OF THE TAF SITES BY 06Z WITH SFC WINDS SHIFTING FROM A SOUTHWEST
DIRECTION INTO A WEST TO NORTHWEST DIRECTION THIS EVENING. SPEEDS
SHOULD BE 10KTS OR LESS TONIGHT AND THEN PICK UP FROM THE NORTHWEST
AT 10 TO 15 KTS TUESDAY.
SMITH
&&
.PREV DISCUSSION...
ISSUED 258 PM CDT MON JUN 11 2012
SHORT TERM...TONIGHT THROUGH THURSDAY
MAIN QUESTION IN THE IMMEDIATE SHORT-TERM IS WHETHER OR NOT ANY
CONVECTION WILL RE-DEVELOP ALONG AN ADVANCING COLD FRONT THIS
EVENING. 2 PM SURFACE ANALYSIS SHOWS FRONT ACROSS EASTERN
IOWA...HOWEVER AIRMASS AHEAD OF IT IS STILL QUITE STABLE DUE TO
MORNING CONVECTION THAT DECAYED ACROSS WEST-CENTRAL ILLINOIS.
LATEST MESO-ANALYSIS FROM SPC IS INDICATING SOME DESTABILIZATION
ALONG THE BOUNDARY...WITH SURFACE-BASED CAPES BACK UP TO AROUND
1500 TO 2000J/KG. 19Z VISIBLE SATELLITE IMAGERY IS SHOWING A
NARROW RIBBON OF CU DEVELOPING IN THE INSTABILITY AXIS...HOWEVER
NO SHOWERS/STORMS HAVE FIRED YET. 12Z MODELS ARE LARGELY
USELESS...AS NONE OF THEM ADEQUATELY PREDICTED THE STORMS THAT
ROLLED ACROSS SOUTH-CENTRAL AND SOUTHEAST ILLINOIS THIS AFTERNOON
ALONG THE LEADING EDGE OF AN OLD OUTFLOW BOUNDARY. EVEN SOME OF
THE HIGHER-RES MODELS SUCH AS THE 4KM WRF FAILED TO CAPTURE THIS
CONVECTION...SO THEIR SOLUTIONS FOR LATE THIS AFTERNOON AND
EVENING ARE SUSPECT. THE 17Z HRRR SEEMS TO HAVE THE BEST HANDLE ON
REALITY...SHOWING THE CURRENT CONVECTION ACROSS THE FAR E/SE KILX
CWA EXITING THE AREA OVER THE NEXT 2 TO 3 HOURS...FOLLOWED BY
LARGELY DRY CONDITIONS THIS EVENING. THE HRRR DOES TRY TO DEVELOP
SOME ISOLATED CONVECTION ALONG THE COLD FRONT AS IT PUSHES INTO
THE ILLINOIS RIVER VALLEY AROUND 00Z...BUT THIS RAPIDLY DISSIPATES
AS DAYTIME INSTABILITY IS LOST AFTER SUNSET. SINCE THE FRONT IS
STILL OFF TO THE WEST...THINK THIS SOLUTION SEEMS REASONABLE...SO
WILL MENTION ISOLATED THUNDER ACROSS THE BOARD DURING THE EARLY
EVENING. AFTER THAT...SKIES WILL CLEAR FROM WEST TO EAST ACROSS
THE AREA AS THE FRONT PUSHES INTO INDIANA AFTER MIDNIGHT.
HIGH PRESSURE WILL BUILD INTO THE GREAT LAKES FOR THE MIDDLE OF
THE WEEK...PROVIDING COOLER AND LESS HUMID CONDITIONS FOR TUESDAY
THROUGH THURSDAY. COOLEST MORNING WILL BE WEDNESDAY MORNING...WHEN
TEMPS FALL INTO THE LOWER 50S. AFTERNOON HIGHS ON WEDNESDAY WILL
BE NEAR OR SLIGHTLY BELOW NORMAL IN THE UPPER 70S/LOWER 80S.
LONG TERM...FRIDAY THROUGH MONDAY
WARMER AND MORE HUMID WEATHER WILL RETURN FOR THE EXTENDED...AS
UPPER TROUGH DIGS ACROSS THE WESTERN CONUS AND RIDGING DEVELOPS
ACROSS THE EAST. MODELS CONTINUE TO DISAGREE ON THE EXACT DEGREE
OF AMPLIFICATION WITHIN THE FLOW...WITH THE 12Z 11 JUN GFS
FEATURING A STRONG RIDGE AND RESULTING DRY CONDITIONS RIGHT
THROUGH EARLY NEXT WEEK. MEANWHILE...THE LATEST ECMWF CONTINUES TO
BE WEAKER WITH THE UPPER RIDGE AND BRINGS A FRONTAL BOUNDARY INTO
THE AREA SUNDAY INTO MONDAY. GIVEN CURRENT MODEL DISCREPANCIES
AND THE FACT THAT PARTS OF CENTRAL ILLINOIS ARE IN A MODERATE
DROUGHT...WILL MAINTAIN HOT AND DRY CONDITIONS THROUGH MONDAY.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
632 PM CDT MON JUN 11 2012
.DISCUSSION...
320 PM CDT
THE FORECAST CONCERNS ARE VERY MINIMAL THROUGH THE REST OF THE
WEEK WITH A CONTINUED DRY PATTERN. WILL BE MONITORING FOR A FEW
STORMS LATE THIS AFTERNOON INTO EARLY EVENING...OTHERWISE THAT MAY
WILL LIKELY BE ALL THAT IS ON THE SCOPE FOR QUITE A WHILE.
ISOLATED SHOWERS WITH A FEW STORMS REDEVELOPING OVER COOK COUNTY
AND SOUTH ALONG THE IL/IN STATE LINE...WHICH IS ALONG AND JUST
AHEAD OF A WEAK CONVERGENT AXIS AND APPARENT SHORT WAVE SEEN ON
SATELLITE. MID 80S TEMPERATURES AND UPPER 60S DEW POINTS ALONG AND
AHEAD OF THIS CORRIDOR HAS BUILT SURFACE BASED CAPE TO AROUND OR
SLIGHTLY OVER 2000 J/KG. THIS CONVECTION SHOULD LAST LONGER THAN
THE PREVIOUS ACTIVITY NEAR NOON BEING CLOSER TO THE SHORT WAVE
CENTER AND HAVING MORE INSTABILITY TO WORK WITH. UPPER LEVEL WIND
SHEAR LOOKS TO BE AROUND A MEAGER 20 KT PER PROFILER ANALYSIS. THE
BEHAVIOR OF THE STORM CORES IS LIKELY TO BE SOMEWHAT PULSY WITH
INSTABILITY IN THE DRIVERS SEAT...AND WITH LIMITED ATTENDANT SHEAR
IT LEAVES ONLY A VERY SMALL CHANCE FOR ANY TYPE OF SEVERE ACTIVITY.
THE SYSTEM UPPER TROUGH CENTER IS LOCATED ALONG THE MN/WESTERN
QUEBEC BORDER WITH PRIMARY HEIGHT FALLS...THE UPPER JET AXIS...AND
ASSOCIATED DEEPER ASCENT MOVING EAST FROM THERE. THIS FORCING HAS
AIDED SOME SHOWER DEVELOPMENT ALONG THE SURFACE COLD FRONT IN
WESTERN WI. THE COOL FRONT EXTENDS SOUTH FROM THERE WHERE IT WILL
MOVE INTO NW IL BY 4 PM AND EAST THROUGH THE FORECAST AREA THIS
EVE. THE WIND SHIFT IS GRADUAL FROM WEST SOUTHWEST TO WEST
NORTHWEST ALONG THE BOUNDARY...AND IT IS ACTUALLY AHEAD OF THE
STRONGEST MOISTURE CONVERGENCE. SO OVERALL CONVERGENCE IS LIMITED
AND FEEL THAT WILL BE THE CASE WITH ANY CONVECTION THAT WERE TO
TRIGGER ALONG IT...WHICH IS NOW APPEARING DOUBTFUL IN OUR AREA.
THE HRRR AND OTHER EXPLICIT CONVECTIVE MODELS AGREE IN THIS
LIMITED COVERAGE.
THE COOL FRONT WILL MOVE THROUGH THE AREA THIS EVENING AND IT
LOOKS LIKE THE BOUNDARY LAYER WILL STAY MIXED AS IT DOES
SUCH...WITH SOME GUSTS UP TO 20 MPH AS THE PRESSURE RISE AXIS
MOVES THROUGH. SUNNY AND DRY WEATHER WILL THEN ONCE AGAIN BE THE
STORY AS CANADIAN HIGH PRESSURE MOVES OVERHEAD TUESDAY NIGHT INTO
WEDNESDAY. THE REALLY ONLY WEATHER OF INTEREST FROM DAY TO DAY WILL
BE HOW LOW DEW POINTS WILL DROP DURING THE AFTERNOON MIXING...AND
TO WHAT DEGREE OF COOLING WILL THERE BE FROM THE LAKE. NORTHWEST
WINDS WILL BEGIN TO DECREASE TUESDAY AFTERNOON...POTENTIALLY
ALLOWING FOR A SLIGHT LAKE BREEZE INTO IL...BUT LIKELY INTO IN.
THIS MAY NOT DEVELOP UNTIL LATE AFTERNOON THOUGH...SO WIDESPREAD
HIGHS IN THE MID TO UPPER 70S ARE EXPECTED. UPSTREAM DEW POINTS
TODAY HAVE BEEN IN THE LOWER TO MID 40S ACROSS EASTERN SD. THIS
AND POSSIBLY EVEN LOWER SHOULD BE REALIZED DURING TUESDAY AFTERNOON
WITH PROJECTED MIXING TO 850 MB. THE AFTERNOON HUMIDITY WILL
REMAIN LOW...UNDER 25 PERCENT...ON WEDNESDAY AFTERNOON WITH THE
SYNOPTIC FLOW TURNING NORTHEAST AND THEN EAST.
INFLUENCE FROM THE LAKE WILL LIKELY CONTINUE TO MOVE INTO CHICAGO
DURING THE AFTERNOON ALL THE WAY THROUGH SATURDAY. THE UPPER LEVEL
HEIGHTS AND LOW-LEVEL THERMAL RIDGE BUILD MORE INTO THE AREA
THURSDAY NIGHT INTO SATURDAY. THE EC HAS SHOWN IN THE UPPER LEVEL
SW FLOW THAT SHORT WAVE ENERGY IS POSSIBLE WITHIN THIS AND MAY
DAMPEN THE RIDGE SLIGHTLY SATURDAY NIGHT INTO SUNDAY...AND HAVE A
SMALL CHANCE FOR POPS DURING PART OF THAT TIME. OTHERWISE...HAVE
COLLABORATED GOING DRIER THAN POPS AND DEW POINTS FROM GUIDANCE
BLENDS IN THE EXTENDED PER PERSISTENCE AND AN OVERALL STAGNANT
PATTERN.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* COLD FROPA THIS EVENING WITH WIND SHIFT FROM SW TO WNW 02-03Z.
* NORTHWEST WINDS TUES VEERING NORTHEAST LATE IN THE DAY.
* VERY LOW PROBABILITY SHRA/TSRA POTENTIAL PRIOR TO FROPA THIS
EVENING.
RATZER
//DISCUSSION...UPDATED 00Z...
LOW PRESSURE PASSING WELL NORTH OF THE LOCAL FORECAST AREA EARLY
THIS EVENING. COLD FRONT TRAILING FROM THIS LOW WAS INTO WESTERN
IL AT 23Z...AND WILL CONTINUE TO PUSH EAST ACROSS THE TERMINALS
OVER THE NEXT FEW HOURS. WINDS HAVE SHIFTED TO 230-250 DEG AHEAD
OF THE FRONT IN THE WAKE OF A PRE-FRONTAL TROUGH WHICH MOVED
THROUGH EARLIER...AND WINDS ARE EXPECTED TO FURTHER SHIFT TO
290-310 DEG AFTER THE COLD FRONT MOVES THROUGH THIS EVENING.
WINDS ARE CURRENTLY SPORADICALLY GUSTING NEAR 20 KTS AHEAD OF THE
FRONT...AND ARE GUSTING INTO THE LOW-MID 20 KT RANGE BEHIND THE
FRONT WITH DEEPER MIXING OF BOUNDARY LAYER IN COOL ADVECTION.
THUS EXPECT SOME GUSTS TO CONTINUE AFTER FROPA THROUGH LATE
EVENING WITH 25-30 KTS NOTED WITHIN MIXED LAYER. SOME QUESTION
EXISTS AS TO HOW QUICKLY BOUNDARY LAYER COOLING WILL RESULT IN
DECREASING GUSTS...BUT SHOULD SEE AT LEAST SOME SPORADIC GUSTS
ABOVE 20 KTS FOR A COUPLE OF HOURS WITH PRESSURE RISES BEHIND THE
FRONT.
HIGH PRESSURE BUILDS SOUTHEAST ACROSS THE REGION TUESDAY...WITH
NORTHWEST WINDS GUSTING INTO THE 15-20 KT RANGE DURING THE DAY.
WINDS WILL EVENTUALLY SHIFT NORTH-NORTHEAST LATE IN THE DAY.
AS FOR SMALL POTENTIAL FOR SHRA/TSRA UNTIL FROPA THIS EVENING...
SPC RAP ANALYSIS CONTINUES TO INDICATE INSTABILITY LINGERING AHEAD
OF COLD FRONT ACROSS NORTHERN IL. HOWEVER...WIND SHIFT ASSOCIATED
WITH EARLIER PRE-FRONTAL TROUGH PASSAGE IS RESULTING IN LITTLE
CONVERGENCE TO SUPPORT SUSTAINED CU DEVELOPMENT OR UPDRAFTS. THUS
WHILE THE PROBABILITY IS NOT ZERO THAT AN ISOLATED TSRA/SHRA COULD
DEVELOP AHEAD OF THE COLD FRONT THIS EVENING...IT IS VERY LOW AND
HAS NOT BEEN MENTIONED IN TAFS.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* MEDIUM-HIGH CONFIDENCE IN FROPA TIMING AND WIND TRENDS THROUGH
THIS EVENING.
* MEDIUM-HIGH CONFIDENCE IN NO ADDITIONA SHRA/TSRA IMPACTING
TERMINALS THIS EVENING.
* HIGH CONFIDENCE IN VFR CONDITIONS AND NORTHWEST WINDS
TUES...MEDIUM CONFIDENCE IN TIMING OF SHIFT TO NORTHEAST LATE
TUES.
RATZER
//OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z...
WEDNESDAY THROUGH SUNDAY...VFR. SLGHT CHC SHRA/TSRA WEST OF
TERMINALS SUNDAY.
RATZER
&&
.MARINE...
231 PM CDT
A LARGE LOW HAS MOVED INTO HUDSON BAY...WHILE HIGH PRESSURE SITS OFF
THE NEW ENGLAND COAST. THE UPPER LEVEL PRESSURE GRADIENT HAS
RELAXED...RESULTING IN SOUTH TO SOUTHWEST WINDS 15-25 KT ACROSS THE
LAKE THIS AFTERNOON. STRONGEST WINDS AROUND 25 KT WILL CONTINUE TO
BE OVER THE NORTHERN HALF OF THE LAKE WHICH IS CLOSER TO THE LOW AND
ITS TIGHT PRESSURE GRADIENT. THE LOWS COLD FRONT WILL SWEEP ACROSS
THE LAKE TONIGHT. WINDS WILL TURN OUT OF THE WEST AT 15 TO 25 KT
ACROSS THE LAKE BEHIND THE FRONT. HIGH PRESSURE MOVES IN BEHIND THE
FRONT TUESDAY NIGHT...WITH WINDS DIMINISHING AND BECOMING NORTHERLY
FOR A ON TUESDAY. THE LIGHT WINDS WILL CONTINUE TO VEER TO EASTERLY
AS THE HIGH MOVES OVER THE LAKE WEDNESDAY. WINDS TURN SOUTHEASTERLY
AS THE HIGH MAKES ITS WAY OVER NORTHERN QUEBEC ON THURSDAY.
ALTHOUGH THE CENTER OF THE HIGH MOVES OFF TO THE NORTHEAST...A LARGE
RIDGE WILL REMAIN OVER THE EASTERN THIRD OF THE US THROUGH THE
REMAINING PART OF THE FORECAST PERIOD. THIS PATTERN WILL RESULT IN
LIGHT WINDS VARYING BETWEEN EAST AND SOUTH.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
611 PM CDT MON JUN 11 2012
.DISCUSSION...
ISSUED 258 PM CDT MON JUN 11 2012
SHORT TERM...TONIGHT THROUGH THURSDAY
MAIN QUESTION IN THE IMMEDIATE SHORT-TERM IS WHETHER OR NOT ANY
CONVECTION WILL RE-DEVELOP ALONG AN ADVANCING COLD FRONT THIS
EVENING. 2 PM SURFACE ANALYSIS SHOWS FRONT ACROSS EASTERN
IOWA...HOWEVER AIRMASS AHEAD OF IT IS STILL QUITE STABLE DUE TO
MORNING CONVECTION THAT DECAYED ACROSS WEST-CENTRAL ILLINOIS.
LATEST MESO-ANALYSIS FROM SPC IS INDICATING SOME DESTABILIZATION
ALONG THE BOUNDARY...WITH SURFACE-BASED CAPES BACK UP TO AROUND
1500 TO 2000J/KG. 19Z VISIBLE SATELLITE IMAGERY IS SHOWING A
NARROW RIBBON OF CU DEVELOPING IN THE INSTABILITY AXIS...HOWEVER
NO SHOWERS/STORMS HAVE FIRED YET. 12Z MODELS ARE LARGELY
USELESS...AS NONE OF THEM ADEQUATELY PREDICTED THE STORMS THAT
ROLLED ACROSS SOUTH-CENTRAL AND SOUTHEAST ILLINOIS THIS AFTERNOON
ALONG THE LEADING EDGE OF AN OLD OUTFLOW BOUNDARY. EVEN SOME OF
THE HIGHER-RES MODELS SUCH AS THE 4KM WRF FAILED TO CAPTURE THIS
CONVECTION...SO THEIR SOLUTIONS FOR LATE THIS AFTERNOON AND
EVENING ARE SUSPECT. THE 17Z HRRR SEEMS TO HAVE THE BEST HANDLE ON
REALITY...SHOWING THE CURRENT CONVECTION ACROSS THE FAR E/SE KILX
CWA EXITING THE AREA OVER THE NEXT 2 TO 3 HOURS...FOLLOWED BY
LARGELY DRY CONDITIONS THIS EVENING. THE HRRR DOES TRY TO DEVELOP
SOME ISOLATED CONVECTION ALONG THE COLD FRONT AS IT PUSHES INTO
THE ILLINOIS RIVER VALLEY AROUND 00Z...BUT THIS RAPIDLY DISSIPATES
AS DAYTIME INSTABILITY IS LOST AFTER SUNSET. SINCE THE FRONT IS
STILL OFF TO THE WEST...THINK THIS SOLUTION SEEMS REASONABLE...SO
WILL MENTION ISOLATED THUNDER ACROSS THE BOARD DURING THE EARLY
EVENING. AFTER THAT...SKIES WILL CLEAR FROM WEST TO EAST ACROSS
THE AREA AS THE FRONT PUSHES INTO INDIANA AFTER MIDNIGHT.
HIGH PRESSURE WILL BUILD INTO THE GREAT LAKES FOR THE MIDDLE OF
THE WEEK...PROVIDING COOLER AND LESS HUMID CONDITIONS FOR TUESDAY
THROUGH THURSDAY. COOLEST MORNING WILL BE WEDNESDAY MORNING...WHEN
TEMPS FALL INTO THE LOWER 50S. AFTERNOON HIGHS ON WEDNESDAY WILL
BE NEAR OR SLIGHTLY BELOW NORMAL IN THE UPPER 70S/LOWER 80S.
LONG TERM...FRIDAY THROUGH MONDAY
WARMER AND MORE HUMID WEATHER WILL RETURN FOR THE EXTENDED...AS
UPPER TROUGH DIGS ACROSS THE WESTERN CONUS AND RIDGING DEVELOPS
ACROSS THE EAST. MODELS CONTINUE TO DISAGREE ON THE EXACT DEGREE
OF AMPLIFICATION WITHIN THE FLOW...WITH THE 12Z 11 JUN GFS
FEATURING A STRONG RIDGE AND RESULTING DRY CONDITIONS RIGHT
THROUGH EARLY NEXT WEEK. MEANWHILE...THE LATEST ECMWF CONTINUES TO
BE WEAKER WITH THE UPPER RIDGE AND BRINGS A FRONTAL BOUNDARY INTO
THE AREA SUNDAY INTO MONDAY. GIVEN CURRENT MODEL DISCREPANCIES
AND THE FACT THAT PARTS OF CENTRAL ILLINOIS ARE IN A MODERATE
DROUGHT...WILL MAINTAIN HOT AND DRY CONDITIONS THROUGH MONDAY.
&&
.AVIATION...
ISSUED 605 PM CDT MON JUN 11 2012
VFR CONDITIONS TO PREVAIL THRU TUESDAY. COLD FRONT WAS NOW PUSHING
INTO WEST CENTRAL ILLINOIS AND WILL CONTINUE TO SHIFT EAST ACRS THE
FORECAST AREA THIS EVENING. CLOUD COVER FROM MCS THAT SHIFTED THRU
SOUTHERN ILLINOIS AND WEAK LOW LEVEL CONVERGENCE ALONG FRONT WILL
KEEP PRECIP CHANCES MINIMAL THIS EVENING. FRONT SHOULD SHIFT EAST
OF THE TAF SITES BY 06Z WITH SFC WINDS SHIFTING FROM A SOUTHWEST
DIRECTION INTO A WEST TO NORTHWEST DIRECTION THIS EVENING. SPEEDS
SHOULD BE 10KTS OR LESS TONIGHT AND THEN PICK UP FROM THE NORTHWEST
AT 10 TO 15 KTS TUESDAY.
SMITH
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
257 PM CDT SUN JUN 10 2012
.DISCUSSION...
ISSUED 257 PM CDT SUN JUN 10 2012
SHORT TERM...TONIGHT THROUGH WEDNESDAY
UPPER-LEVEL DISTURBANCE CURRENTLY OVER THE LOWER MISSISSIPPI
RIVER VALLEY WILL CONTINUE TO SPREAD MOISTURE NORTHWARD INTO THE
REGION TONIGHT. LATEST SATELLITE/RADAR LOOPS INDICATE THE DEEPER
MOISTURE AND ASSOCIATED PRECIP ARE PRIMARILY LIMITED TO LOCATIONS
ALONG AND TO THE RIGHT OF THIS FEATURE. AS A RESULT...THE BEST
RAIN CHANCES WILL SPREAD INTO THE TENNESSEE AND OHIO RIVER
VALLEYS TONIGHT...GENERALLY STAYING EAST OF ILLINOIS. HIGH-RES
MODELS SUCH AS THE HRRR ARE KEEPING THE KILX CWA DRY...HOWEVER
WITH DEEPER MOISTURE COMING SO CLOSE TO THE E/SE...HAVE OPTED TO
MAINTAIN A SLIM CHANCE FOR SHOWERS ALONG/EAST OF I-57 TONIGHT.
MEANWHILE...VIGOROUS UPPER WAVE OVER THE NORTHERN ROCKIES WILL
TRACK ALONG THE CANADIAN BORDER TOWARD THE NORTHERN GREAT LAKES BY
MONDAY EVENING. TRAILING COLD FRONT WILL CROSS THE MISSISSIPPI
RIVER BY AROUND MIDDAY MONDAY AND BE LOCATED ALONG THE I-55
CORRIDOR BY EARLY MONDAY EVENING. AIRMASS AHEAD OF THE FRONT WILL
BECOME MODERATELY UNSTABLE...CHARACTERIZED BY CAPE VALUES OF 1500
TO 2500J/KG. MITIGATING FACTOR FOR WIDESPREAD THUNDERSTORMS AND
SEVERE POTENTIAL WILL BE LACK OF WIND SHEAR. FORECAST SOUNDINGS
INDICATE WEAK WIND PROFILE THROUGHOUT THE ENTIRE DEPTH OF THE
ATMOSPHERE AND VERY WEAK 0-6 KM BULK SHEAR VALUES OF 15 TO 25KT.
DESPITE LACK OF SHEAR...ADEQUATE INSTABILITY AND GOOD CONVERGENCE
ALONG THE ADVANCING FRONT WILL RESULT IN A BROKEN LINE OF
STORMS...WITH A LOW PROBABILITY FOR SEVERE. PRIMARY TIME FRAME
WILL BE DURING THE LATE MORNING/AFTERNOON WEST OF I-55...AND
DURING THE EVENING FURTHER EAST. ANY CONVECTION WILL QUICKLY EXIT
INTO INDIANA AFTER MIDNIGHT...WITH CLEARING SKIES NOTED FROM WEST
TO EAST ACROSS THE AREA TOWARD DAWN.
HIGH PRESSURE WILL BUILD INTO THE GREAT LAKES BEHIND THE DEPARTING
COLD FRONT ON TUESDAY AND WEDNESDAY...BRINGING A COOLER/DRIER
AIRMASS INTO THE REGION. WITH 850MB TEMPS PROGGED TO DROP INTO THE
12 TO 14C RANGE...HIGHS WILL FALL BACK TO NEAR NORMAL FOR THIS
TIME OF YEAR IN THE UPPER 70S/LOWER 80S.
LONG TERM...THURSDAY THROUGH SUNDAY
MODELS CONTINUE TO ADVERTISE UPPER TROUGHING DEVELOPING ACROSS THE
WESTERN CONUS BY THE END OF THE WEEK...RESULTING IN DOWNSTREAM
RIDGING AND WARMER WEATHER FOR THE MIDWEST. EXACT EVOLUTION AND
DEGREE OF AMPLIFICATION STILL REMAIN IN QUESTION...WITH A
SLIGHTLY DIFFERENT SOLUTION FEATURED ON EACH SUCCESSIVE MODEL RUN.
GIVEN UNCERTAINTIES...HAVE OPTED TO MAINTAIN A DRY FORECAST
THROUGH NEXT WEEKEND EVEN THOUGH THE ECMWF SUGGESTS A FRONT MAY
APPROACH FROM THE NORTHWEST BY SUNDAY. 12Z 10 JUN GFS IS MUCH
STRONGER WITH THE EASTERN RIDGE AND DEVELOPS A REX BLOCK ACROSS
THE GREAT LAKES/OHIO RIVER VALLEY. IF THIS SOLUTION PANS OUT...THE
NEXT CHANCE FOR RAIN WOULD BE DELAYED PERHAPS UNTIL THE MIDDLE OF
NEXT WEEK. WILL THEREFORE MAINTAIN WARM/DRY CONDITIONS THROUGH
SUNDAY...UNTIL BETTER MODEL CONSISTENCY IS ACHIEVED.
BARNES
&&
.AVIATION...
ISSUED 1255 PM CDT SUN JUN 10 2012
VFR CONDITIONS GENERALLY EXPECTED TO CONTINUE THROUGH MONDAY
MORNING ACROSS THE CENTRAL IL AIRPORTS. ISOLATED SHOWERS AND
THUNDERSTORMS WILL STAY SE OF THE CENTRAL IL TERMINAL AIRPORTS
THROUGH TONIGHT WHERE BEST TROPICAL MOISTURE RETURN IS OVER THE
MID MS AND LOWER OHIO VALLEYS AROUND KY INTO SE PARTS OF IL/IN.
994 MB LOW PRESSURE WEST OF LAKE WINNIPEG HAS A COLD FRONT THROUGH
SE SD...EASTERN NEBRASKA AND INTO CENTRAL KS. TIGHT PRESSURE
GRADIENT AHEAD OF COLD FRONT OVER IL TO GIVE BREEZY SOUTH WINDS OF
10-20 KTS WITH GUSTS OF 20-26 KTS THIS AFTERNOON AND WEAKEN TO
7-10 KTS AT SUNSET AND TURN SW AROUND 10 KTS BY 15Z MON. COLD
FRONT TO MOVE SE TOWARD THE IA/IL BORDER BY 18Z/1 PM MON. BROKEN
CLOUDS 4-8K FT TO SPREAD NORTHWARD INTO CENTRAL IL OVERNIGHT AND
CONTINUE INTO MONDAY. HAVE VCTS AFTER 14Z AT PIA...15Z ALONG I-55
AT BMI AND SPI AND 16Z AT DEC FOR ISOLATED CONVECTION POSSIBLE
AHEAD OF APPROACHING COLD FRONT. KEPT CMI DRY THROUGH MON MORNING.
BEST CHANCE OF CONVECTION IN WESTERN IL AIRPORTS MON AFTERNOON AND
EAST CENTRAL IL AIRPORTS MON EVENING.
KH
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
111 PM MDT SUN JUN 10 2012
.UPDATE...
ISSUED AT 1209 PM MDT SUN JUN 10 2012
UPDATED THE ZONES FOR THE EXPIRATION OF THE WESTERN PORTION OF THE
WIND ADVISORY WHICH WAS SET TO EXPIRE AT 18Z. THE EASTERN PORTION
CONTINUES UNTIL 21Z. LATEST MODEL DATA AND OBSERVATIONS SUPPORT
DECREASING TREND OF WIND OVER THE WEST. OTHERWISE NO OTHER CHANGES.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 400 AM MDT SUN JUN 10 2012
FORECAST CONCERNS WILL BE WINDS/HOW COOL TO MAKE IT TODAY...AND
CHANCE OF PRECIPITATION TONIGHT THROUGH TUESDAY NIGHT. SATELLITE IS
SHOWING AN AMPLIFIED AND EVEN RETROGRESSIVE PATTERN FROM THE PACIFIC
INTO THE WESTERN ATLANTIC. DEEP MID/UPPER LEVEL TROUGH HAD SETTLED
INTO THE NORTHWEST PORTION OF THE COUNTRY. COLD FRONT CONTINUES TO
MOVE SLOWLY TOWARD THE AREA.
MODELS WERE HAVING A LITTLE TROUBLE WITH THE JET SEGMENT BEHIND THE
INCOMING UPPER TROUGH. THEY TENDED TO BE TOO LOW IN THE PACIFIC
NORTHWEST. THE GFS FOLLOWED BY THE ECMWF WERE DOING THE BEST. THE
GFS/CANADIAN/UKMET LOOKED TO CAPTURE INCOMING UPPER LOW THE BEST
ALTHOUGH BY 06Z WERE NOT TOO FAR APART. LARGER SCALE MODELS HAVING
A HARD TIME WITH THE INCOMING FRONT. PARTICULARLY THEY WERE HAVING
TROUBLE WITH THE SURFACE LOW THAT WAS LOCATED OVER NORTHEAST
COLORADO. THE SMALLER MODELS...HRRR/RUC...WERE CATCHING THE
PRESSURE WIND FIELD THE BEST. THE ECMWF WAS INITIALLY CATCHING THE
LOW LEVEL THERMAL FIELD THE BEST. ALSO THE HRRR/RUC WERE DOING FINE
WITH THIS AS WELL.
TODAY/TONIGHT...INITIAL PROBLEM WILL BE HOW STRONG TO MAKE THE WINDS
BEHIND THE FRONT. DEPENDING ON WHICH MODEL YOU CHOOSE IT IS BARELY
ABOVE WIND ADVISORY CRITERIA OR A SOLID ADVISORY. STILL DIFFERENCES
IN HOW FAST THE MODELS BRING IT IN AND HOW MUCH TO COOL THE
TEMPERATURES BEHIND IT. NAM/RUC/HRRR WERE STILL BRINGING AN EXTREMELY
TIGHT GRADIENT AND VERY HIGH 3 HOUR PRESSURE RISES OF UP TO 10 MB.
THIS IS SHOWN BY THE ANALYSIS AND OBSERVATIONS UPSTREAM WERE
GUSTING UP TO AS HIGH AS 45 KNOTS. HRRR WAS BRINGING 40+ KNOT GUSTS
ACROSS THE ENTIRE AREA WITH THE EASTERN AND SOUTHERN FRINGES HAVING
THE LOWEST GUSTS.
AS A RESULT...HOISTED A WIND ADVISORY UNTIL 18Z FOR THE WEST AND
FROM 15Z TO 21Z FOR THE EAST. IF FRONT COMES IN FASTER MAY HAVE
READJUST THE EASTERN ZONES. MODELS HAVE DONE A DOWNWARD TREND IN
TEMPERATURES AND WILL HAVE SOME THICK CLOUDS THIS MORNING. PROBLEM
IS THAT MANY LOCATIONS ARE STILL RATHER MILD. PER THE RUC/HRRR
ADJUSTED MAXES DOWN EXCEPT FOR THE FAR EAST AND SOUTH.
JET COMING IN DURING THE NIGHT IS FURTHER NORTH THAN LAST NIGHT.
RIGHT REAR QUADRANT MAINLY AFFECTS THE NORTHERN PORTION OF THE AREA
AFTER 06Z. MODELS DID CHANGE IN ANOTHER AWAY. THEY ARE MORE UNSTABLE
WITH SOME ELEVATED CAPE INDICATED PLUS THETA-E LAPSE RATES ARE VERY
FAVORABLE FOR A GOOD RESPONSE FROM THE RATHER STRONG MESOSCALE MID
LEVEL FORCING AND MODERATE SYNOPTIC SCALE LIFT. SO INSERTED SOME
THUNDER BACK INTO THE FORECAST. WAS IS INTERESTING IS THAT GEFS AND
SREFS PROBABILITIES FOR MEASURABLE HAVE INCREASED DRAMATICALLY IN
THE SOUTHWEST PORTION. DOES MAKE SENSE CONSIDERING ABOVE DISCUSSION
BUT AM NOT TOTALLY SOLD ON THAT YET. BUT DID RAISE POPS INTO LOW
CHANCE CATEGORY TO TREND IN THAT DIRECTION.
MONDAY...LIGHT AND VARIABLE WINDS BEHIND COLD FRONT. RIGHT REAR
QUADRANT REMAINS NEAR THE NORTHERN PORTION OF THE AREA THROUGH THE
DAY WHICH MAY KEEP CLOUDS AROUND. NAM NWP/2 METER HAVE BEEN DOING
BEST BUT DO NOT WANT TO WARM IT UP TOO MUCH DUE TO THE UNFAVORABLE
WINDS.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 103 PM MDT SUN JUN 10 2012
A ZONAL FLOW ALOFT WILL START THE PERIOD AND CONTINUE THROUGH THE
END OF THE WEEK...THEN THE FLOW AMPLIFIES AHEAD OF A TROUGH MOVING
INTO THE GREAT BASIN WITH RISING HEIGHTS AND SOUTHWEST FLOW OVER
THE PLAINS OVER THE WEEKEND. MONDAY NIGHT...WITH POST FRONTAL
UPSLOPE REGIME AND POSSIBLY A WEAK SHORTWAVE IN THE ZONAL FLOW
CANNOT DISCOUNT POSSIBILITY OF AN ISOLATED STORM MOVING IN FROM
COLORADO. CONFIDENCE IS VERY LOW IN THIS HAPPENING. THE PATTERN
REPEATS ON TUESDAY AND MODELS APPEAR TOO WET...WITH THE ECMWF
NOTABLY DRY. NONETHELESS...SINCE WE ARE OUTLOOKED BY SPC AND OTHER
MODELS ARE QUITE WET WILL BUMP UP POPS IN THE WEST TO LOW CHANCE.
MODELS CONTINUE TO BE WET THE REST OF THE EXTENDED. MY CONFIDENCE
BEYOND DAY 4 IS VERY LOW GIVEN THE UPPER PATTERN AND RECENT DROUGHT
CONDITIONS. TEMPERATURES WILL START THE PERIOD SLIGHTLY BELOW
NORMAL...GRADUALLY WARMING TO NEAR AND SLIGHTLY ABOVE NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1209 PM MDT SUN JUN 10 2012
VFR CONDITIONS EXPECTED AT KGLD AND KMCK FOR THE NEXT 24 HOURS.
NORTH WIND WILL DECREASE THROUGH THE AFTERNOON WITH GENERALLY
LIGHT WIND OVERNIGHT. SOME MID LEVEL BROKEN CLOUDS EXPECTED WITH
DISTURBANCE MOVING THROUGH THE AREA BUT NO PRECIPITATION AT THE
SITES OTHER THAN A SPRINKLE DUE TO A VERY DRY LAYER FROM THE
SURFACE TO 600MB.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WIND ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR KSZ003-004-015-
016-029.
CO...NONE.
NE...WIND ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR NEZ081.
&&
$$
UPDATE...FS
SHORT TERM...BULLER
LONG TERM...024
AVIATION...FS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1213 PM MDT SUN JUN 10 2012
.UPDATE...
ISSUED AT 1209 PM MDT SUN JUN 10 2012
UPDATED THE ZONES FOR THE EXPIRATION OF THE WESTERN PORTION OF THE
WIND ADVISORY WHICH WAS SET TO EXPIRE AT 18Z. THE EASTERN PORTION
CONTINUES UNTIL 21Z. LATEST MODEL DATA AND OBSERVATIONS SUPPORT
DECREASING TREND OF WIND OVER THE WEST. OTHERWISE NO OTHER CHANGES.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 400 AM MDT SUN JUN 10 2012
FORECAST CONCERNS WILL BE WINDS/HOW COOL TO MAKE IT TODAY...AND
CHANCE OF PRECIPITATION TONIGHT THROUGH TUESDAY NIGHT. SATELLITE IS
SHOWING AN AMPLIFIED AND EVEN RETROGRESSIVE PATTERN FROM THE PACIFIC
INTO THE WESTERN ATLANTIC. DEEP MID/UPPER LEVEL TROUGH HAD SETTLED
INTO THE NORTHWEST PORTION OF THE COUNTRY. COLD FRONT CONTINUES TO
MOVE SLOWLY TOWARD THE AREA.
MODELS WERE HAVING A LITTLE TROUBLE WITH THE JET SEGMENT BEHIND THE
INCOMING UPPER TROUGH. THEY TENDED TO BE TOO LOW IN THE PACIFIC
NORTHWEST. THE GFS FOLLOWED BY THE ECMWF WERE DOING THE BEST. THE
GFS/CANADIAN/UKMET LOOKED TO CAPTURE INCOMING UPPER LOW THE BEST
ALTHOUGH BY 06Z WERE NOT TOO FAR APART. LARGER SCALE MODELS HAVING
A HARD TIME WITH THE INCOMING FRONT. PARTICULARLY THEY WERE HAVING
TROUBLE WITH THE SURFACE LOW THAT WAS LOCATED OVER NORTHEAST
COLORADO. THE SMALLER MODELS...HRRR/RUC...WERE CATCHING THE
PRESSURE WIND FIELD THE BEST. THE ECMWF WAS INITIALLY CATCHING THE
LOW LEVEL THERMAL FIELD THE BEST. ALSO THE HRRR/RUC WERE DOING FINE
WITH THIS AS WELL.
TODAY/TONIGHT...INITIAL PROBLEM WILL BE HOW STRONG TO MAKE THE WINDS
BEHIND THE FRONT. DEPENDING ON WHICH MODEL YOU CHOOSE IT IS BARELY
ABOVE WIND ADVISORY CRITERIA OR A SOLID ADVISORY. STILL DIFFERENCES
IN HOW FAST THE MODELS BRING IT IN AND HOW MUCH TO COOL THE
TEMPERATURES BEHIND IT. NAM/RUC/HRRR WERE STILL BRINGING AN EXTREMELY
TIGHT GRADIENT AND VERY HIGH 3 HOUR PRESSURE RISES OF UP TO 10 MB.
THIS IS SHOWN BY THE ANALYSIS AND OBSERVATIONS UPSTREAM WERE
GUSTING UP TO AS HIGH AS 45 KNOTS. HRRR WAS BRINGING 40+ KNOT GUSTS
ACROSS THE ENTIRE AREA WITH THE EASTERN AND SOUTHERN FRINGES HAVING
THE LOWEST GUSTS.
AS A RESULT...HOISTED A WIND ADVISORY UNTIL 18Z FOR THE WEST AND
FROM 15Z TO 21Z FOR THE EAST. IF FRONT COMES IN FASTER MAY HAVE
READJUST THE EASTERN ZONES. MODELS HAVE DONE A DOWNWARD TREND IN
TEMPERATURES AND WILL HAVE SOME THICK CLOUDS THIS MORNING. PROBLEM
IS THAT MANY LOCATIONS ARE STILL RATHER MILD. PER THE RUC/HRRR
ADJUSTED MAXES DOWN EXCEPT FOR THE FAR EAST AND SOUTH.
JET COMING IN DURING THE NIGHT IS FURTHER NORTH THAN LAST NIGHT.
RIGHT REAR QUADRANT MAINLY AFFECTS THE NORTHERN PORTION OF THE AREA
AFTER 06Z. MODELS DID CHANGE IN ANOTHER AWAY. THEY ARE MORE UNSTABLE
WITH SOME ELEVATED CAPE INDICATED PLUS THETA-E LAPSE RATES ARE VERY
FAVORABLE FOR A GOOD RESPONSE FROM THE RATHER STRONG MESOSCALE MID
LEVEL FORCING AND MODERATE SYNOPTIC SCALE LIFT. SO INSERTED SOME
THUNDER BACK INTO THE FORECAST. WAS IS INTERESTING IS THAT GEFS AND
SREFS PROBABILITIES FOR MEASURABLE HAVE INCREASED DRAMATICALLY IN
THE SOUTHWEST PORTION. DOES MAKE SENSE CONSIDERING ABOVE DISCUSSION
BUT AM NOT TOTALLY SOLD ON THAT YET. BUT DID RAISE POPS INTO LOW
CHANCE CATEGORY TO TREND IN THAT DIRECTION.
MONDAY...LIGHT AND VARIABLE WINDS BEHIND COLD FRONT. RIGHT REAR
QUADRANT REMAINS NEAR THE NORTHERN PORTION OF THE AREA THROUGH THE
DAY WHICH MAY KEEP CLOUDS AROUND. NAM NWP/2 METER HAVE BEEN DOING
BEST BUT DO NOT WANT TO WARM IT UP TOO MUCH DUE TO THE UNFAVORABLE
WINDS.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 400 AM MDT SUN JUN 10 2012
MONDAY NIGHT...WEAK RIGHT REAR QUADRANT MOVES AWAY DURING THE
NIGHT. ALSO SOME WEAK LIFT APPROACHING FROM THE WEST. WILL NOT BE
TERRIBLY UNSTABLE DUE TO LACK OF MOISTURE RETURN BEHIND FRONT.
HOWEVER...NEW GUIDANCE MATCHED CURRENT FORECAST WELL AND MADE NO
CHANGES.
TUESDAY/TUESDAY NIGHT...MODELS ALL OVER THE PLACE WITH THE QPF.
THERE IS INSTABILITY AND SOME KIND OF LIFT MOVING THROUGH. HOWEVER...
MODELS DO APPEAR TO BE SUFFERING FROM CONVECTIVE FEEDBACK. DOES
APPEAR TO BE A DECENT CHANCE FOR THUNDERSTORMS. BUT DUE TO MODEL
VARIABILITY LEFT THE FORECAST AS IS.
WEDNESDAY THROUGH SATURDAY...A ZONAL FLOW PATTERN WILL SET UP ACROSS
MUCH OF THE CONUS IN THE WAKE OF UPPER LEVEL LOW MOVING INTO THE
HUDSON BAY REGION. SURFACE HIGH WILL ALSO MOVE EASTWARD INTO THE
GREAT LAKES REGION. A SHORTWAVE TROUGH WILL MOVE THROUGH THE FLOW
TUESDAY NIGHT WITH THE POSSIBILITY OF SHOWERS AND SCATTERED
THUNDERSTORMS LINGERING INTO WEDNESDAY MORNING. SCATTERED
THUNDERSTORMS ARE EXPECTED EACH AFTERNOON THROUGH THE END OF THE WEEK
AS LEE TROUGH SETS UP ALONG THE HIGH PLAINS AND SOUTHERLY WINDS
ADVECT UNSTABLE AIRMASS NORTH. THESE SCATTERED THUNDERSTORMS WILL BE
DIURNALLY DRIVEN AS FORCING APPEARS TO BE QUITE WEAK WITH UPPER LEVEL
JET MAX POSITIONED OVER THE NORTHERN PLAINS. BY THE END OF THE
WEEK...TEMPERATURES WILL WARM INTO THE 90S AS UPPER LEVEL RIDGE
BUILDS OVER THE CENTRAL PLAINS AHEAD OF NEXT UPPER LOW TO MOVE ACROSS
THE NORTHERN PLAINS. MODELS ARE IN GOOD AGREEMENT ON BRINGING A COLD
FRONT THROUGH LATE IN THE WEEK THROUGH THE EARLY WEEKEND HOURS.
THANKS TO ALL WHO COLLABORATED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1209 PM MDT SUN JUN 10 2012
VFR CONDITIONS EXPECTED AT KGLD AND KMCK FOR THE NEXT 24 HOURS.
NORTH WIND WILL DECREASE THROUGH THE AFTERNOON WITH GENERALLY
LIGHT WIND OVERNIGHT. SOME MID LEVEL BROKEN CLOUDS EXPECTED WITH
DISTURBANCE MOVING THROUGH THE AREA BUT NO PRECIPITATION AT THE
SITES OTHER THAN A SPRINKLE DUE TO A VERY DRY LAYER FROM THE
SURFACE TO 600MB.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WIND ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR KSZ003-004-015-
016-029.
CO...NONE.
NE...WIND ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR NEZ081.
&&
$$
UPDATE...FS
SHORT TERM...BULLER
LONG TERM....BULLER/PM
AVIATION...FS
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1220 PM CDT SUN JUN 10 2012
...UPDATED AVIATION SECTION...
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 345 AM CDT SUN JUN 10 2012
TODAY:
THE MAIN WEATHER CONCERN FOR TODAY IS THE PASSAGE OF A COLD FRONT. AT
08Z, THE FRONT WAS LOCATED ACROSS NORTHEASTERN COLORADO. AHEAD OF THIS
FRONT, IT WAS WARM WITH TEMPERATURES IN THE 70S DEG F AND DEWPOINTS
IN THE 60S DEG F. THE HRRR IS CURRENTLY DOING A GOOD JOB WITH THE POSITION
OF THE FRONT. HAVE USED A BLEND OF THE HRRR IN THE VERY SHORT TERM AND
THEN THE NAM LATER TODAY WITH FRONTAL TIMING. I DID COOL MY NORTHWEST
COUNTIES DOWN BY A FEW DEGREES. THE BCCONSRAW OUTPUT WAS USED WITH A
FEW ALTERATIONS AS BOISE VERIFICATION SHOWS THIS MODEL IS OUTPERFORMING
OTHER GUIDANCE. THERE IS A LOW END CONCERN FOR ADVISORY LEVEL NORTHERLY
WINDS GENERALLY NORTH OF HIGHWAY 96. WITH THE FROPA, THERE WILL BE A
BRIEF WINDOW OF NEAR ADVISORY LEVEL WINDS BUT GIVEN THE QUICK WINDOW
OF THE ISALLOBARIC RESPONSE AND MARGINAL BOUNDARY LAYER WINDS, THOUGHT
IT WAS BEST TO HOLD OFF FOR NOW. TEMPERATURES WILL VARY ACROSS THE REGION
WITH AROUND 80 DEG F TOWARDS SCOTT CITY TO AROUND 91 DEG F AT MEDICINE
LODGE. NO PRECIPITATION IS EXPECTED TODAY IN ASSOCIATION WITH THE FRONT
DUE TO THE VERY STOUT EML WITH 700 HPA TEMPERATURES FORECAST AROUND
15 DEG C THIS AFTERNOON "COOLING" OFF TO AROUND 12 DEG C BY TONIGHT.
TONIGHT:
I HAVE RAMPED UP POPS ACROSS SOUTH CENTRAL KANSAS MAINLY AFTER MIDNIGHT
AS THE EML WEAKENS IN RESPONSE TO COOLING OF LOW TO MID LEVEL TEMPERATURES
ASSOCIATED WITH THE PASSAGE OF AN UPPER LEVEL SHORTWAVE TROUGH. THERE
WILL BE A WINDOW FOR STRONG TO SEVERE STORMS THROUGH THE OVERNIGHT PERIOD
TOWARDS MEDICINE LODGE. ML/MUCAPE IS FORECAST TO BE AROUND 1000 J/KG
WITH 45 KT OF 0 TO 6 KM SHEAR. MARGINAL 700-500 HPA LAPSE RATES OF 7.0
C/KM AND 500-300 HPA LAPSE RATES AROUND 7.1 C/KM SUGGEST THE POTENTIAL
FOR HAIL UP TO THE SIZE OF QUARTERS. ANVIL LEVEL SR WINDS ARE FAIRLY
DECENT AT 37 KT BUT THE FACT THAT CONVECTION WILL BE ELEVATED AND NOT
SURFACE BASED WILL LIMIT OVERALL POTENTIAL FOR HAIL BIGGER THAN QUARTERS.
OVERNIGHT LOWS WILL BE COOLER THAN COMPARED TO THIS MORNINGS LOWS WITH
50S & 60S DEG F EXPECTED.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 252 AM CDT SUN JUN 10 2012
BY EARLY MONDAY THE SURFACE COLD FRONT IS EXPECTED TO MOVE INTO
SOUTHERN OKLAHOMA. 850MB WARM AIR ADVECTION NORTH OF THE SURFACE
COLD FRONT AT 12Z MONDAY APPEARS TO BE LOCATED ACROSS NORTHERN
OKLAHOMA AND SOUTH CENTRAL KANSAS. 850-700MB FRONTOGENESIS WILL
ALSO BE LOCATED NEAR SOUTH CENTRAL KANSAS AS AN UPPER LEVEL JET
MOVES ACROSS EASTERN NEBRASKA. NAM AND ECMWF INDICATING SOME MID
LEVEL MOISTURE WILL BE POOLING NEAR THE 700MB BAROCLINIC ZONE
WHICH AT 12Z MONDAY WILL EXTEND ACROSS SOUTH CENTRAL KANSAS.
GIVEN THIS FORCING, MOISTURE, AND LOCATION OF THE RIGHT ENTRANCE
REGION OF THE UPPER LEVEL JET WILL KEEP A MENTION OF SHOWERS AND
THUNDERSTORMS GOING ACROSS SOUTH CENTRAL KANSAS EARLY MONDAY.
PRECIPITATION CHANCES WILL DECREASE DURING THE AFTERNOON AS THE
UPPER JET MOVES EAST OF THE AREA AND THE 700MB BAROCLINIC ZONE
STARTS TO DROP SOUTH.
ON MONDAY NIGHT 700MB WARM AIR ADVECTION AND I310 ISENTROPIC LIFT
BEGINS TO IMPROVE ACROSS SOUTHWEST KANSAS. BASED ON VARIOUS MODEL
SOUNDINGS IT APPEARS MOISTURE WILL BE AT OR ABOVE 800MB LEVEL
WHICH WILL BE WHERE THIS LIFT IS EXPECTED TO DEVELOP SO HIGH BASED
CONVECTION WILL BE POSSIBLE. CURRENTLY HAVE MENTION OF
PRECIPITATION GOING IN THE PORTIONS OF WESTERN KANSAS LATE MONDAY
NIGHT/EARLY TUESDAY WHICH IS WHERE THIS LIFT IS EXPECTED TO
DEVELOP SO THE INITIAL THOUGHTS ARE TO STAY CLOSE TO PREVIOUS
FORECAST.
MORE SEASONAL TEMPERATURES WILL RETURN EARLY NEXT WEEK AS 850MB
TEMPERATURES FALL BACK INTO THE 6 TO 10C RANGE BY 00Z TUESDAY. AS
AN AREA OF HIGH PRESSURE AT THE SURFACE MOVES SOUTHEAST INTO THE
MID MISSISSIPPI VALLEY THROUGH MID WEEK AND WESTERLY DOWN SLOPE FLOW
IMPROVES A GRADUAL WARMING TREND IS EXPECTED TO DEVELOP.
AN UPPER LEVEL TROUGH WILL BEGIN TO MOVE ACROSS THE WESTERN UNITED
STATES LATE WEEK AND THE WESTERLY FLOW ACROSS THE ROCKIES WILL
BACK MORE TO THE SOUTHWEST. AN ELEVATED MIXED LAYER WILL START TO
MOVE INTO WESTERN KANSAS WITH 850MB TEMPERATURES REBOUNDING BACK
INTO THE MID TO UPPER 20S. BASED ON THESE WARMING 850-700MB
TEMPERATURES THE HIGHS LATE WEEK AREA EXPECTED TO BE AT LEAST AS
WARM AS THOSE CURRENTLY IN THE GRIDS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1220 PM CDT SUN JUN 10 2012
THE SURFACE COLD FRONT HAS MOVED THROUGH THE TAF SITES SHIFTING
WINDS TO THE NORTHWEST AT 15 TO 20 KNOTS GUSTING TO OVER 25 KNOTS
AT TIMES. WINDS WILL SHIFT TO MORE OF A NORTHERLY DIRECTION LATE
THIS AFTERNOON THEN DECREASE TO BELOW 12 KNOTS BY SUNSET. VFR
CONDITIONS WILL PREVAIL WITH A FEW HIGH CLOUDS AOA150 MOVING IN
THIS EVENING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 86 59 86 60 / 10 20 20 10
GCK 83 57 85 58 / 10 10 10 10
EHA 85 57 85 59 / 10 10 10 20
LBL 88 61 87 61 / 10 20 20 20
HYS 83 58 86 57 / 10 10 10 10
P28 91 65 88 63 / 10 30 30 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...SUGDEN
LONG TERM...BURGERT
AVIATION...HOVORKA_42
AREA FORECAST DISCUSSION
NWS GOODLAND KS
531 AM MDT SUN JUN 10 2012
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 400 AM MDT SUN JUN 10 2012
FORECAST CONCERNS WILL BE WINDS/HOW COOL TO MAKE IT TODAY...AND
CHANCE OF PRECIPITATION TONIGHT THROUGH TUESDAY NIGHT. SATELLITE IS
SHOWING AN AMPLIFIED AND EVEN RETROGRESSIVE PATTERN FROM THE PACIFIC
INTO THE WESTERN ATLANTIC. DEEP MID/UPPER LEVEL TROUGH HAD SETTLED
INTO THE NORTHWEST PORTION OF THE COUNTRY. COLD FRONT CONTINUES TO
MOVE SLOWLY TOWARD THE AREA.
MODELS WERE HAVING A LITTLE TROUBLE WITH THE JET SEGMENT BEHIND THE
INCOMING UPPER TROUGH. THEY TENDED TO BE TOO LOW IN THE PACIFIC
NORTHWEST. THE GFS FOLLOWED BY THE ECMWF WERE DOING THE BEST. THE
GFS/CANADIAN/UKMET LOOKED TO CAPTURE INCOMING UPPER LOW THE BEST
ALTHOUGH BY 06Z WERE NOT TOO FAR APART. LARGER SCALE MODELS HAVING
A HARD TIME WITH THE INCOMING FRONT. PARTICULARLY THEY WERE HAVING
TROUBLE WITH THE SURFACE LOW THAT WAS LOCATED OVER NORTHEAST
COLORADO. THE SMALLER MODELS...HRRR/RUC...WERE CATCHING THE
PRESSURE WIND FIELD THE BEST. THE ECMWF WAS INITIALLY CATCHING THE
LOW LEVEL THERMAL FIELD THE BEST. ALSO THE HRRR/RUC WERE DOING FINE
WITH THIS AS WELL.
TODAY/TONIGHT...INITIAL PROBLEM WILL BE HOW STRONG TO MAKE THE WINDS
BEHIND THE FRONT. DEPENDING ON WHICH MODEL YOU CHOOSE IT IS BARELY
ABOVE WIND ADVISORY CRITERIA OR A SOLID ADVISORY. STILL DIFFERENCES
IN HOW FAST THE MODELS BRING IT IN AND HOW MUCH TO COOL THE
TEMPERATURES BEHIND IT. NAM/RUC/HRRR WERE STILL BRINGING AN EXTREMELY
TIGHT GRADIENT AND VERY HIGH 3 HOUR PRESSURE RISES OF UP TO 10 MB.
THIS IS SHOWN BY THE ANALYSIS AND OBSERVATIONS UPSTREAM WERE
GUSTING UP TO AS HIGH AS 45 KNOTS. HRRR WAS BRINGING 40+ KNOT GUSTS
ACROSS THE ENTIRE AREA WITH THE EASTERN AND SOUTHERN FRINGES HAVING
THE LOWEST GUSTS.
AS A RESULT...HOISTED A WIND ADVISORY UNTIL 18Z FOR THE WEST AND
FROM 15Z TO 21Z FOR THE EAST. IF FRONT COMES IN FASTER MAY HAVE
READJUST THE EASTERN ZONES. MODELS HAVE DONE A DOWNWARD TREND IN
TEMPERATURES AND WILL HAVE SOME THICK CLOUDS THIS MORNING. PROBLEM
IS THAT MANY LOCATIONS ARE STILL RATHER MILD. PER THE RUC/HRRR
ADJUSTED MAXES DOWN EXCEPT FOR THE FAR EAST AND SOUTH.
JET COMING IN DURING THE NIGHT IS FURTHER NORTH THAN LAST NIGHT.
RIGHT REAR QUADRANT MAINLY AFFECTS THE NORTHERN PORTION OF THE AREA
AFTER 06Z. MODELS DID CHANGE IN ANOTHER AWAY. THEY ARE MORE UNSTABLE
WITH SOME ELEVATED CAPE INDICATED PLUS THETA-E LAPSE RATES ARE VERY
FAVORABLE FOR A GOOD RESPONSE FROM THE RATHER STRONG MESOSCALE MID
LEVEL FORCING AND MODERATE SYNOPTIC SCALE LIFT. SO INSERTED SOME
THUNDER BACK INTO THE FORECAST. WAS IS INTERESTING IS THAT GEFS AND
SREFS PROBABILITIES FOR MEASURABLE HAVE INCREASED DRAMATICALLY IN
THE SOUTHWEST PORTION. DOES MAKE SENSE CONSIDERING ABOVE DISCUSSION
BUT AM NOT TOTALLY SOLD ON THAT YET. BUT DID RAISE POPS INTO LOW
CHANCE CATEGORY TO TREND IN THAT DIRECTION.
MONDAY...LIGHT AND VARIABLE WINDS BEHIND COLD FRONT. RIGHT REAR
QUADRANT REMAINS NEAR THE NORTHERN PORTION OF THE AREA THROUGH THE
DAY WHICH MAY KEEP CLOUDS AROUND. NAM NWP/2 METER HAVE BEEN DOING
BEST BUT DO NOT WANT TO WARM IT UP TOO MUCH DUE TO THE UNFAVORABLE
WINDS.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 400 AM MDT SUN JUN 10 2012
MONDAY NIGHT...WEAK RIGHT REAR QUADRANT MOVES AWAY DURING THE
NIGHT. ALSO SOME WEAK LIFT APPROACHING FROM THE WEST. WILL NOT BE
TERRIBLY UNSTABLE DUE TO LACK OF MOISTURE RETURN BEHIND FRONT.
HOWEVER...NEW GUIDANCE MATCHED CURRENT FORECAST WELL AND MADE NO
CHANGES.
TUESDAY/TUESDAY NIGHT...MODELS ALL OVER THE PLACE WITH THE QPF.
THERE IS INSTABILITY AND SOME KIND OF LIFT MOVING THROUGH. HOWEVER...
MODELS DO APPEAR TO BE SUFFERING FROM CONVECTIVE FEEDBACK. DOES
APPEAR TO BE A DECENT CHANCE FOR THUNDERSTORMS. BUT DUE TO MODEL
VARIABILITY LEFT THE FORECAST AS IS.
WEDNESDAY THROUGH SATURDAY...A ZONAL FLOW PATTERN WILL SET UP ACROSS
MUCH OF THE CONUS IN THE WAKE OF UPPER LEVEL LOW MOVING INTO THE
HUDSON BAY REGION. SURFACE HIGH WILL ALSO MOVE EASTWARD INTO THE
GREAT LAKES REGION. A SHORTWAVE TROUGH WILL MOVE THROUGH THE FLOW
TUESDAY NIGHT WITH THE POSSIBILITY OF SHOWERS AND SCATTERED
THUNDERSTORMS LINGERING INTO WEDNESDAY MORNING. SCATTERED
THUNDERSTORMS ARE EXPECTED EACH AFTERNOON THROUGH THE END OF THE WEEK
AS LEE TROUGH SETS UP ALONG THE HIGH PLAINS AND SOUTHERLY WINDS
ADVECT UNSTABLE AIRMASS NORTH. THESE SCATTERED THUNDERSTORMS WILL BE
DIURNALLY DRIVEN AS FORCING APPEARS TO BE QUITE WEAK WITH UPPER LEVEL
JET MAX POSITIONED OVER THE NORTHERN PLAINS. BY THE END OF THE
WEEK...TEMPERATURES WILL WARM INTO THE 90S AS UPPER LEVEL RIDGE
BUILDS OVER THE CENTRAL PLAINS AHEAD OF NEXT UPPER LOW TO MOVE ACROSS
THE NORTHERN PLAINS. MODELS ARE IN GOOD AGREEMENT ON BRINGING A COLD
FRONT THROUGH LATE IN THE WEEK THROUGH THE EARLY WEEKEND HOURS.
THANKS TO ALL WHO COLLABORATED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 527 AM MDT SUN JUN 10 2012
MAIN PROBLEM WILL BE GUSTY WINDS INTO THIS AFTERNOON. WINDS HAVE SHIFTED
OR WILL SHORTLY SHIFT TO THE NORTHWEST THEN NORTH. ONCE THE WINDS
DECREASE THEY WILL GO LIGHT AND VARIABLE THROUGH THE REST OF THE
PERIOD. THERE MAY BE A BRIEF PERIOD OF MVFR CEILINGS. NOT SURE HOW
FAR SOUTH THOSE CEILINGS SO HANDLED IT WITH TEMPO GROUPS.
POSSIBILITY OF LIGHT PRECIPITATION NEAR KGLD LATER TONIGHT. SINCE
PRECIPITATION SHOULD BE LIGHT AND IT IS LATER ON IN THE PERIOD
CHOSE NOT TO MENTION ANYTHING AT THIS TIME.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WIND ADVISORY UNTIL NOON MDT /1 PM CDT/ TODAY FOR KSZ001-002-013-
014-027-028-041-042.
WIND ADVISORY FROM 10 AM THIS MORNING TO 4 PM CDT THIS AFTERNOON
FOR KSZ003-004-015-016-029.
CO...WIND ADVISORY UNTIL NOON MDT TODAY FOR COZ090>092.
NE...WIND ADVISORY UNTIL NOON MDT /1 PM CDT/ TODAY FOR NEZ079-080.
WIND ADVISORY FROM 10 AM THIS MORNING TO 4 PM CDT THIS AFTERNOON
FOR NEZ081.
&&
$$
SHORT TERM...BULLER
LONG TERM....BULLER/PM
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
627 AM CDT SUN JUN 10 2012
...UPDATED FOR AVIATION DISCUSSION...
.SYNOPSIS...
ISSUED AT 345 AM CDT SUN JUN 10 2012
THE FOLLOWING CHART ANALYSIS WAS CONDUCTED USING THE 10.00Z CONSTANT
PRESSURE MAPS VIA THE RAOB NETWORK. THE 250 HPA MAP SHOWED A HIGHLY
AMPLIFIED CYCLONICALLY CURVED JET WITH THE TROF AXIS FROM WESTERN ALBERTA
SOUTHWARD TO NORTHEASTERN NEVADA. A JET MAX OF 100 KT WAS OBSERVED FROM
KUIL (QUILLAYUTE, WA) TO KSLE (SALEM, OR). ANOTHER 115 KT WAS FORECAST
BY THE RAP MODEL SINCE IT WAS BETWEEN UPPER AIR SITES ACROSS SE MONTANA.
FARTHER EAST, ANOTHER 100 KT NORTHWESTERLY JET WAS LOCATED ACROSS EASTERN
ONTARIO. AT 500 HPA, A 550 DM CYCLONE WAS ANALYZED ACROSS EXTREME SOUTHERN
ALBERTA INTO MONTANA. COLD H5 TEMPERATURES AROUND -24 DEG C WAS OBSERVED
AT KTFX (GREAT FALLS, MT) TO KBOI (BOISE, ID). ANOTHER SUBTROPICAL LOW
WAS LOCATED ACROSS LOUISIANA WITH MID LEVEL MOISTURE ADVECTION DOWNSTREAM
OF SAID PRESSURE PERTURBATION. AT 700/850 HPA, THE EML EXTENDED ACROSS
MOST OF THE PLAINS WITH H7 TEMPERATURES IN THE 12 TO 16 DEG C RANGE.
850 HPA TEMPERATURES WERE ALSO VERY WARM WITH TEMPERATURES RANGING FROM
33 DEG C AT KMAF (MIDLAND, TX) TO 23 DEG C AT KABR (ABERDEEN, SD). SOME
LOW TO MID LEVEL MOISTURE WAS FOUND ACROSS THE GULF COAST IN ASSOCIATION
WITH THE AFOREMENTIONED GULF COAST LOW. AT THE SFC, A LOW PRESSURE CENTER
WAS LOCATED ACROSS EASTERN NORTH DAKOTA WITH A WARM FRONT EXTENDING
NORTHWARD INTO SOUTHERN MANITOBA AND ONTARIO. A COLD FRONT ALSO EXTENDED
FROM THIS LOW REACHED INTO WYOMING. CLOSER TO KANSAS, A LEE SURFACE
TROUGH WITH AN ASSOCIATED DRYLINE WAS LOCATED ACROSS FAR WESTERN KANSAS
WITH DEWPOINTS RUNNING IN THE LOW 60S DEG F ACROSS WC/SC KANSAS.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 345 AM CDT SUN JUN 10 2012
TODAY:
THE MAIN WEATHER CONCERN FOR TODAY IS THE PASSAGE OF A COLD FRONT. AT
08Z, THE FRONT WAS LOCATED ACROSS NORTHEASTERN COLORADO. AHEAD OF THIS
FRONT, IT WAS WARM WITH TEMPERATURES IN THE 70S DEG F AND DEWPOINTS
IN THE 60S DEG F. THE HRRR IS CURRENTLY DOING A GOOD JOB WITH THE POSITION
OF THE FRONT. HAVE USED A BLEND OF THE HRRR IN THE VERY SHORT TERM AND
THEN THE NAM LATER TODAY WITH FRONTAL TIMING. I DID COOL MY NORTHWEST
COUNTIES DOWN BY A FEW DEGREES. THE BCCONSRAW OUTPUT WAS USED WITH A
FEW ALTERATIONS AS BOISE VERIFICATION SHOWS THIS MODEL IS OUTPERFORMING
OTHER GUIDANCE. THERE IS A LOW END CONCERN FOR ADVISORY LEVEL NORTHERLY
WINDS GENERALLY NORTH OF HIGHWAY 96. WITH THE FROPA, THERE WILL BE A
BRIEF WINDOW OF NEAR ADVISORY LEVEL WINDS BUT GIVEN THE QUICK WINDOW
OF THE ISALLOBARIC RESPONSE AND MARGINAL BOUNDARY LAYER WINDS, THOUGHT
IT WAS BEST TO HOLD OFF FOR NOW. TEMPERATURES WILL VARY ACROSS THE REGION
WITH AROUND 80 DEG F TOWARDS SCOTT CITY TO AROUND 91 DEG F AT MEDICINE
LODGE. NO PRECIPITATION IS EXPECTED TODAY IN ASSOCIATION WITH THE FRONT
DUE TO THE VERY STOUT EML WITH 700 HPA TEMPERATURES FORECAST AROUND
15 DEG C THIS AFTERNOON "COOLING" OFF TO AROUND 12 DEG C BY TONIGHT.
TONIGHT:
I HAVE RAMPED UP POPS ACROSS SOUTH CENTRAL KANSAS MAINLY AFTER MIDNIGHT
AS THE EML WEAKENS IN RESPONSE TO COOLING OF LOW TO MID LEVEL TEMPERATURES
ASSOCIATED WITH THE PASSAGE OF AN UPPER LEVEL SHORTWAVE TROUGH. THERE
WILL BE A WINDOW FOR STRONG TO SEVERE STORMS THROUGH THE OVERNIGHT PERIOD
TOWARDS MEDICINE LODGE. ML/MUCAPE IS FORECAST TO BE AROUND 1000 J/KG
WITH 45 KT OF 0 TO 6 KM SHEAR. MARGINAL 700-500 HPA LAPSE RATES OF 7.0
C/KM AND 500-300 HPA LAPSE RATES AROUND 7.1 C/KM SUGGEST THE POTENTIAL
FOR HAIL UP TO THE SIZE OF QUARTERS. ANVIL LEVEL SR WINDS ARE FAIRLY
DECENT AT 37 KT BUT THE FACT THAT CONVECTION WILL BE ELEVATED AND NOT
SURFACE BASED WILL LIMIT OVERALL POTENTIAL FOR HAIL BIGGER THAN QUARTERS.
OVERNIGHT LOWS WILL BE COOLER THAN COMPARED TO THIS MORNINGS LOWS WITH
50S & 60S DEG F EXPECTED.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 252 AM CDT SUN JUN 10 2012
BY EARLY MONDAY THE SURFACE COLD FRONT IS EXPECTED TO MOVE INTO
SOUTHERN OKLAHOMA. 850MB WARM AIR ADVECTION NORTH OF THE SURFACE
COLD FRONT AT 12Z MONDAY APPEARS TO BE LOCATED ACROSS NORTHERN
OKLAHOMA AND SOUTH CENTRAL KANSAS. 850-700MB FRONTOGENESIS WILL
ALSO BE LOCATED NEAR SOUTH CENTRAL KANSAS AS AN UPPER LEVEL JET
MOVES ACROSS EASTERN NEBRASKA. NAM AND ECMWF INDICATING SOME MID
LEVEL MOISTURE WILL BE POOLING NEAR THE 700MB BAROCLINIC ZONE
WHICH AT 12Z MONDAY WILL EXTEND ACROSS SOUTH CENTRAL KANSAS.
GIVEN THIS FORCING, MOISTURE, AND LOCATION OF THE RIGHT ENTRANCE
REGION OF THE UPPER LEVEL JET WILL KEEP A MENTION OF SHOWERS AND
THUNDERSTORMS GOING ACROSS SOUTH CENTRAL KANSAS EARLY MONDAY.
PRECIPITATION CHANCES WILL DECREASE DURING THE AFTERNOON AS THE
UPPER JET MOVES EAST OF THE AREA AND THE 700MB BAROCLINIC ZONE
STARTS TO DROP SOUTH.
ON MONDAY NIGHT 700MB WARM AIR ADVECTION AND I310 ISENTROPIC LIFT
BEGINS TO IMPROVE ACROSS SOUTHWEST KANSAS. BASED ON VARIOUS MODEL
SOUNDINGS IT APPEARS MOISTURE WILL BE AT OR ABOVE 800MB LEVEL
WHICH WILL BE WHERE THIS LIFT IS EXPECTED TO DEVELOP SO HIGH BASED
CONVECTION WILL BE POSSIBLE. CURRENTLY HAVE MENTION OF
PRECIPITATION GOING IN THE PORTIONS OF WESTERN KANSAS LATE MONDAY
NIGHT/EARLY TUESDAY WHICH IS WHERE THIS LIFT IS EXPECTED TO
DEVELOP SO THE INITIAL THOUGHTS ARE TO STAY CLOSE TO PREVIOUS
FORECAST.
MORE SEASONAL TEMPERATURES WILL RETURN EARLY NEXT WEEK AS 850MB
TEMPERATURES FALL BACK INTO THE 6 TO 10C RANGE BY 00Z TUESDAY. AS
AN AREA OF HIGH PRESSURE AT THE SURFACE MOVES SOUTHEAST INTO THE
MID MISSISSIPPI VALLEY THROUGH MID WEEK AND WESTERLY DOWN SLOPE FLOW
IMPROVES A GRADUAL WARMING TREND IS EXPECTED TO DEVELOP.
AN UPPER LEVEL TROUGH WILL BEGIN TO MOVE ACROSS THE WESTERN UNITED
STATES LATE WEEK AND THE WESTERLY FLOW ACROSS THE ROCKIES WILL
BACK MORE TO THE SOUTHWEST. AN ELEVATED MIXED LAYER WILL START TO
MOVE INTO WESTERN KANSAS WITH 850MB TEMPERATURES REBOUNDING BACK
INTO THE MID TO UPPER 20S. BASED ON THESE WARMING 850-700MB
TEMPERATURES THE HIGHS LATE WEEK AREA EXPECTED TO BE AT LEAST AS
WARM AS THOSE CURRENTLY IN THE GRIDS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 620 AM CDT SUN JUN 10 2012
COLD FRONT SURGING SOUTH/SOUTHEAST ACROSS EASTERN COLORADO AND
NORTHWEST KANSAS AS OF 10Z. HRRR AND RAP DOING A DECENT JOB ON
TIMING OF THIS FRONTAL PASSAGE SO WILL USE THESE MODELS AS A GUIDE
FOR THE WIND SHIFT AS THE COLD FRONT CROSSES WESTERN KANSAS LATER
THIS MORNING. AS THIS FRONT PASSES GUSTY NORTHWEST WINDS OF UP TO
26KTS WILL BRIEFLY BE POSSIBLE AFTER FROPA BUT THESE WINDS ARE
EXPECTED TO SUBSIDE BACK INTO THE 20 TO 25 KNOT RANGE WITHIN ONE
TO TWO HOURS. THESE GUSTY WINDS WILL CONTINUE TO SUBSIDE THROUGH
THE AFTERNOON AND EVENING PERIOD. BUFR SOUNDINGS ALSO SUGGESTING A
BRIEF PERIOD OF LOW VFR SCT-BKN DECK...MAINLY AT HYS UNTIL 18Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 86 59 86 60 / 10 20 20 10
GCK 83 57 85 58 / 10 10 10 10
EHA 85 57 85 59 / 10 10 10 20
LBL 88 61 87 61 / 10 20 20 20
HYS 83 58 86 57 / 10 10 10 10
P28 91 65 88 63 / 10 30 30 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...SUGDEN
SHORT TERM...SUGDEN
LONG TERM...BURGERT
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS GOODLAND KS
400 AM MDT SUN JUN 10 2012
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 400 AM MDT SUN JUN 10 2012
FORECAST CONCERNS WILL BE WINDS/HOW COOL TO MAKE IT TODAY...AND
CHANCE OF PRECIPITATION TONIGHT THROUGH TUESDAY NIGHT. SATELLITE IS
SHOWING AN AMPLIFIED AND EVEN RETROGRESSIVE PATTERN FROM THE PACIFIC
INTO THE WESTERN ATLANTIC. DEEP MID/UPPER LEVEL TROUGH HAD SETTLED
INTO THE NORTHWEST PORTION OF THE COUNTRY. COLD FRONT CONTINUES TO
MOVE SLOWLY TOWARD THE AREA.
MODELS WERE HAVING A LITTLE TROUBLE WITH THE JET SEGMENT BEHIND THE
INCOMING UPPER TROUGH. THEY TENDED TO BE TOO LOW IN THE PACIFIC
NORTHWEST. THE GFS FOLLOWED BY THE ECMWF WERE DOING THE BEST. THE
GFS/CANADIAN/UKMET LOOKED TO CAPTURE INCOMING UPPER LOW THE BEST
ALTHOUGH BY 06Z WERE NOT TOO FAR APART. LARGER SCALE MODELS HAVING
A HARD TIME WITH THE INCOMING FRONT. PARTICULARLY THEY WERE HAVING
TROUBLE WITH THE SURFACE LOW THAT WAS LOCATED OVER NORTHEAST
COLORADO. THE SMALLER MODELS...HRRR/RUC...WERE CATCHING THE
PRESSURE WIND FIELD THE BEST. THE ECMWF WAS INITIALLY CATCHING THE
LOW LEVEL THERMAL FIELD THE BEST. ALSO THE HRRR/RUC WERE DOING FINE
WITH THIS AS WELL.
TODAY/TONIGHT...INITIAL PROBLEM WILL BE HOW STRONG TO MAKE THE WINDS
BEHIND THE FRONT. DEPENDING ON WHICH MODEL YOU CHOOSE IT IS BARELY
ABOVE WIND ADVISORY CRITERIA OR A SOLID ADVISORY. STILL DIFFERENCES
IN HOW FAST THE MODELS BRING IT IN AND HOW MUCH TO COOL THE
TEMPERATURES BEHIND IT. NAM/RUC/HRRR WERE STILL BRINGING AN EXTREMELY
TIGHT GRADIENT AND VERY HIGH 3 HOUR PRESSURE RISES OF UP TO 10 MB.
THIS IS SHOWN BY THE ANALYSIS AND OBSERVATIONS UPSTREAM WERE
GUSTING UP TO AS HIGH AS 45 KNOTS. HRRR WAS BRINGING 40+ KNOT GUSTS
ACROSS THE ENTIRE AREA WITH THE EASTERN AND SOUTHERN FRINGES HAVING
THE LOWEST GUSTS.
AS A RESULT...HOISTED A WIND ADVISORY UNTIL 18Z FOR THE WEST AND
FROM 15Z TO 21Z FOR THE EAST. IF FRONT COMES IN FASTER MAY HAVE
READJUST THE EASTERN ZONES. MODELS HAVE DONE A DOWNWARD TREND IN
TEMPERATURES AND WILL HAVE SOME THINK CLOUDS THIS MORNING. PROBLEM
IS THAT MANY LOCATIONS ARE STILL RATHER MILD. PER THE RUC/HRRR
ADJUSTED MAXES DOWN EXCEPT FOR THE FAR EAST AND SOUTH.
JET COMING IN DURING THE NIGHT IS FURTHER NORTH THAN LAST NIGHT.
RIGHT REAR QUADRANT MAINLY AFFECTS THE NORTHERN PORTION OF THE AREA
AFTER 06Z. MODELS DID CHANGE IN ANOTHER AWAY. THEY ARE MORE UNSTABLE
WITH SOME ELEVATED CAPE INDICATED PLUS THETA-E LAPSE RATES ARE VERY
FAVORABLE FOR A GOOD RESPONSE FROM THE RATHER STRONG MESOSCALE MID
LEVEL FORCING AND MODERATE SYNOPTIC SCALE LIFT. SO INSERTED SOME
THUNDER BACK INTO THE FORECAST. WAS IS INTERESTING IS THAT GEFS AND
SREFS PROBABILITIES FOR MEASURABLE HAVE INCREASED DRAMATICALLY IN
THE SOUTHWEST PORTION. DOES MAKE SENSE CONSIDERING ABOVE DISCUSSION
BUT AM NOT TOTALLY SOLD ON THAT YET. BUT DID RAISE POPS INTO LOW
CHANCE CATEGORY TO TREND IN THAT DIRECTION.
MONDAY...LIGHT AND VARIABLE WINDS BEHIND COLD FRONT. RIGHT REAR
QUADRANT REMAINS NEAR THE NORTHERN PORTION OF THE AREA THROUGH THE
DAY WHICH MAY KEEP CLOUDS AROUND. NAM NWP/2 METER HAVE BEEN DOING
BEST BUT DO NOT WANT TO WARM IT UP TOO MUCH DUE TO THE UNFAVORABLE
WINDS.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 400 AM MDT SUN JUN 10 2012
MONDAY NIGHT...WEAK RIGHT REAR QUADRANT MOVES AWAY DURING THE
NIGHT. ALSO SOME WEAK LIFT APPROACHING FROM THE WEST. WILL NOT BE
TERRIBLY UNSTABLE DUE TO LACK OF MOISTURE RETURN BEHIND FRONT.
HOWEVER...NEW GUIDANCE MATCHED CURRENT FORECAST WELL AND MADE NO
CHANGES.
TUESDAY/TUESDAY NIGHT...MODELS ALL OVER THE PLACE WITH THE QPF.
THERE IS INSTABILITY AND SOME KIND OF LIFT MOVING THROUGH. HOWEVER...
MODELS DO APPEAR TO BE SUFFERING FROM CONVECTIVE FEEDBACK. DOES
APPEAR TO BE A DECENT CHANCE FOR THUNDERSTORMS. BUT DUE TO MODEL
VARIABILITY LEFT THE FORECAST AS IS.
WEDNESDAY THROUGH SATURDAY...A ZONAL FLOW PATTERN WILL SET UP ACROSS
MUCH OF THE CONUS IN THE WAKE OF UPPER LEVEL LOW MOVING INTO THE
HUDSON BAY REGION. SURFACE HIGH WILL ALSO MOVE EASTWARD INTO THE
GREAT LAKES REGION. A SHORTWAVE TROUGH WILL MOVE THROUGH THE FLOW
TUESDAY NIGHT WITH THE POSSIBILITY OF SHOWERS AND SCATTERED
THUNDERSTORMS LINGERING INTO WEDNESDAY MORNING. SCATTERED
THUNDERSTORMS ARE EXPECTED EACH AFTERNOON THROUGH THE END OF THE WEEK
AS LEE TROUGH SETS UP ALONG THE HIGH PLAINS AND SOUTHERLY WINDS
ADVECT UNSTABLE AIRMASS NORTH. THESE SCATTERED THUNDERSTORMS WILL BE
DIURNALLY DRIVEN AS FORCING APPEARS TO BE QUITE WEAK WITH UPPER LEVEL
JET MAX POSITIONED OVER THE NORTHERN PLAINS. BY THE END OF THE
WEEK...TEMPERATURES WILL WARM INTO THE 90S AS UPPER LEVEL RIDGE
BUILDS OVER THE CENTRAL PLAINS AHEAD OF NEXT UPPER LOW TO MOVE ACROSS
THE NORTHERN PLAINS. MODELS ARE IN GOOD AGREEMENT ON BRINGING A COLD
FRONT THROUGH LATE IN THE WEEK THROUGH THE EARLY WEEKEND HOURS.
THANKS TO ALL WHO COLLABORATED.
&&
.AVIATION...FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1133 PM MDT SAT JUN 9 2012
WINDS CONTINUE TO REMAIN GUSTY AT BOTH KGLD AND KMCK AND BASED ON
UPSTREAM OBS...SHOULD DO SO UNTIL THE COLD FRONT REACHES THE AREA.
DO EXPECT A PERIOD OF VARIABLE BUT GUSTY WINDS FOR A COUPLE OF
HOURS AS WINDS GRADUALLY VEER TO THE NORTHWEST BEHIND THE FRONT.
GUIDANCE CONTINUES TO DEPICT SEVERAL HOURS OF STRONG WIND GUSTS
APPROACHING IF NOT EXCEEDING 40 KTS. COULD ALSO SEE PERIODIC MVFR
CIGS AND HAVE INSERTED A TEMPO GROUP FOR THIS POSSIBILITY. WINDS
GRADUALLY DIMINISH BY MID/LATE AFTERNOON AND BECOME LIGHT AND
VARIABLE AFTER 02Z MONDAY.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WIND ADVISORY UNTIL NOON MDT /1 PM CDT/ TODAY FOR
KSZ001-002-013-014-027-028-041-042.
WIND ADVISORY FROM 10 AM THIS MORNING TO 4 PM CDT THIS
AFTERNOON FOR KSZ003-004-015-016-029.
CO...WIND ADVISORY UNTIL NOON MDT TODAY FOR COZ090>092.
NE...WIND ADVISORY UNTIL NOON MDT /1 PM CDT/ TODAY FOR NEZ079-080.
WIND ADVISORY FROM 10 AM THIS MORNING TO 4 PM CDT THIS
AFTERNOON FOR NEZ081.
&&
$$
SHORT TERM...BULLER
LONG TERM....BULLER/PM
AVIATION...FOLTZ
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
345 AM CDT SUN JUN 10 2012
...UPDATE TO SYNOPSIS AND SHORT TERM DISCUSSIONS...
.SYNOPSIS...
ISSUED AT 345 AM CDT SUN JUN 10 2012
THE FOLLOWING CHART ANALYSIS WAS CONDUCTED USING THE 10.00Z CONSTANT
PRESSURE MAPS VIA THE RAOB NETWORK. THE 250 HPA MAP SHOWED A HIGHLY
AMPLIFIED CYCLONICALLY CURVED JET WITH THE TROF AXIS FROM WESTERN ALBERTA
SOUTHWARD TO NORTHEASTERN NEVADA. A JET MAX OF 100 KT WAS OBSERVED FROM
KUIL (QUILLAYUTE, WA) TO KSLE (SALEM, OR). ANOTHER 115 KT WAS FORECAST
BY THE RAP MODEL SINCE IT WAS BETWEEN UPPER AIR SITES ACROSS SE MONTANA.
FARTHER EAST, ANOTHER 100 KT NORTHWESTERLY JET WAS LOCATED ACROSS EASTERN
ONTARIO. AT 500 HPA, A 550 DM CYCLONE WAS ANALYZED ACROSS EXTREME SOUTHERN
ALBERTA INTO MONTANA. COLD H5 TEMPERATURES AROUND -24 DEG C WAS OBSERVED
AT KTFX (GREAT FALLS, MT) TO KBOI (BOISE, ID). ANOTHER SUBTROPICAL LOW
WAS LOCATED ACROSS LOUISIANA WITH MID LEVEL MOISTURE ADVECTION DOWNSTREAM
OF SAID PRESSURE PERTURBATION. AT 700/850 HPA, THE EML EXTENDED ACROSS
MOST OF THE PLAINS WITH H7 TEMPERATURES IN THE 12 TO 16 DEG C RANGE.
850 HPA TEMPERATURES WERE ALSO VERY WARM WITH TEMPERATURES RANGING FROM
33 DEG C AT KMAF (MIDLAND, TX) TO 23 DEG C AT KABR (ABERDEEN, SD). SOME
LOW TO MID LEVEL MOISTURE WAS FOUND ACROSS THE GULF COAST IN ASSOCIATION
WITH THE AFOREMENTIONED GULF COAST LOW. AT THE SFC, A LOW PRESSURE CENTER
WAS LOCATED ACROSS EASTERN NORTH DAKOTA WITH A WARM FRONT EXTENDING
NORTHWARD INTO SOUTHERN MANITOBA AND ONTARIO. A COLD FRONT ALSO EXTENDED
FROM THIS LOW REACHED INTO WYOMING. CLOSER TO KANSAS, A LEE SURFACE
TROUGH WITH AN ASSOCIATED DRYLINE WAS LOCATED ACROSS FAR WESTERN KANSAS
WITH DEWPOINTS RUNNING IN THE LOW 60S DEG F ACROSS WC/SC KANSAS.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 345 AM CDT SUN JUN 10 2012
TODAY:
THE MAIN WEATHER CONCERN FOR TODAY IS THE PASSAGE OF A COLD FRONT. AT
08Z, THE FRONT WAS LOCATED ACROSS NORTHEASTERN COLORADO. AHEAD OF THIS
FRONT, IT WAS WARM WITH TEMPERATURES IN THE 70S DEG F AND DEWPOINTS
IN THE 60S DEG F. THE HRRR IS CURRENTLY DOING A GOOD JOB WITH THE POSITION
OF THE FRONT. HAVE USED A BLEND OF THE HRRR IN THE VERY SHORT TERM AND
THEN THE NAM LATER TODAY WITH FRONTAL TIMING. I DID COOL MY NORTHWEST
COUNTIES DOWN BY A FEW DEGREES. THE BCCONSRAW OUTPUT WAS USED WITH A
FEW ALTERATIONS AS BOISE VERIFICATION SHOWS THIS MODEL IS OUTPERFORMING
OTHER GUIDANCE. THERE IS A LOW END CONCERN FOR ADVISORY LEVEL NORTHERLY
WINDS GENERALLY NORTH OF HIGHWAY 96. WITH THE FROPA, THERE WILL BE A
BRIEF WINDOW OF NEAR ADVISORY LEVEL WINDS BUT GIVEN THE QUICK WINDOW
OF THE ISALLOBARIC RESPONSE AND MARGINAL BOUNDARY LAYER WINDS, THOUGHT
IT WAS BEST TO HOLD OFF FOR NOW. TEMPERATURES WILL VARY ACROSS THE REGION
WITH AROUND 80 DEG F TOWARDS SCOTT CITY TO AROUND 91 DEG F AT MEDICINE
LODGE. NO PRECIPITATION IS EXPECTED TODAY IN ASSOCIATION WITH THE FRONT
DUE TO THE VERY STOUT EML WITH 700 HPA TEMPERATURES FORECAST AROUND
15 DEG C THIS AFTERNOON "COOLING" OFF TO AROUND 12 DEG C BY TONIGHT.
TONIGHT:
I HAVE RAMPED UP POPS ACROSS SOUTH CENTRAL KANSAS MAINLY AFTER MIDNIGHT
AS THE EML WEAKENS IN RESPONSE TO COOLING OF LOW TO MID LEVEL TEMPERATURES
ASSOCIATED WITH THE PASSAGE OF AN UPPER LEVEL SHORTWAVE TROUGH. THERE
WILL BE A WINDOW FOR STRONG TO SEVERE STORMS THROUGH THE OVERNIGHT PERIOD
TOWARDS MEDICINE LODGE. ML/MUCAPE IS FORECAST TO BE AROUND 1000 J/KG
WITH 45 KT OF 0 TO 6 KM SHEAR. MARGINAL 700-500 HPA LAPSE RATES OF 7.0
C/KM AND 500-300 HPA LAPSE RATES AROUND 7.1 C/KM SUGGEST THE POTENTIAL
FOR HAIL UP TO THE SIZE OF QUARTERS. ANVIL LEVEL SR WINDS ARE FAIRLY
DECENT AT 37 KT BUT THE FACT THAT CONVECTION WILL BE ELEVATED AND NOT
SURFACE BASED WILL LIMIT OVERALL POTENTIAL FOR HAIL BIGGER THAN QUARTERS.
OVERNIGHT LOWS WILL BE COOLER THAN COMPARED TO THIS MORNINGS LOWS WITH
50S & 60S DEG F EXPECTED.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 252 AM CDT SUN JUN 10 2012
BY EARLY MONDAY THE SURFACE COLD FRONT IS EXPECTED TO MOVE INTO
SOUTHERN OKLAHOMA. 850MB WARM AIR ADVECTION NORTH OF THE SURFACE
COLD FRONT AT 12Z MONDAY APPEARS TO BE LOCATED ACROSS NORTHERN
OKLAHOMA AND SOUTH CENTRAL KANSAS. 850-700MB FRONTOGENESIS WILL
ALSO BE LOCATED NEAR SOUTH CENTRAL KANSAS AS AN UPPER LEVEL JET
MOVES ACROSS EASTERN NEBRASKA. NAM AND ECMWF INDICATING SOME MID
LEVEL MOISTURE WILL BE POOLING NEAR THE 700MB BAROCLINIC ZONE
WHICH AT 12Z MONDAY WILL EXTEND ACROSS SOUTH CENTRAL KANSAS.
GIVEN THIS FORCING, MOISTURE, AND LOCATION OF THE RIGHT ENTRANCE
REGION OF THE UPPER LEVEL JET WILL KEEP A MENTION OF SHOWERS AND
THUNDERSTORMS GOING ACROSS SOUTH CENTRAL KANSAS EARLY MONDAY.
PRECIPITATION CHANCES WILL DECREASE DURING THE AFTERNOON AS THE
UPPER JET MOVES EAST OF THE AREA AND THE 700MB BAROCLINIC ZONE
STARTS TO DROP SOUTH.
ON MONDAY NIGHT 700MB WARM AIR ADVECTION AND I310 ISENTROPIC LIFT
BEGINS TO IMPROVE ACROSS SOUTHWEST KANSAS. BASED ON VARIOUS MODEL
SOUNDINGS IT APPEARS MOISTURE WILL BE AT OR ABOVE 800MB LEVEL
WHICH WILL BE WHERE THIS LIFT IS EXPECTED TO DEVELOP SO HIGH BASED
CONVECTION WILL BE POSSIBLE. CURRENTLY HAVE MENTION OF
PRECIPITATION GOING IN THE PORTIONS OF WESTERN KANSAS LATE MONDAY
NIGHT/EARLY TUESDAY WHICH IS WHERE THIS LIFT IS EXPECTED TO
DEVELOP SO THE INITIAL THOUGHTS ARE TO STAY CLOSE TO PREVIOUS
FORECAST.
MORE SEASONAL TEMPERATURES WILL RETURN EARLY NEXT WEEK AS 850MB
TEMPERATURES FALL BACK INTO THE 6 TO 10C RANGE BY 00Z TUESDAY. AS
AN AREA OF HIGH PRESSURE AT THE SURFACE MOVES SOUTHEAST INTO THE
MID MISSISSIPPI VALLEY THROUGH MID WEEK AND WESTERLY DOWN SLOPE FLOW
IMPROVES A GRADUAL WARMING TREND IS EXPECTED TO DEVELOP.
AN UPPER LEVEL TROUGH WILL BEGIN TO MOVE ACROSS THE WESTERN UNITED
STATES LATE WEEK AND THE WESTERLY FLOW ACROSS THE ROCKIES WILL
BACK MORE TO THE SOUTHWEST. AN ELEVATED MIXED LAYER WILL START TO
MOVE INTO WESTERN KANSAS WITH 850MB TEMPERATURES REBOUNDING BACK
INTO THE MID TO UPPER 20S. BASED ON THESE WARMING 850-700MB
TEMPERATURES THE HIGHS LATE WEEK AREA EXPECTED TO BE AT LEAST AS
WARM AS THOSE CURRENTLY IN THE GRIDS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1200 AM CDT SUN JUN 10 2012
JUST A FEW MINOR TWEAKS TO THE 06Z TAFS FROM THE 00Z TAFS AS THE OVERALL
TIMING OF THE FRONT STILL LOOKS ON TRACK. I DO HAVE A CONCERN THAT KHYS
MIGHT SEE NEAR 25 KT NORTHERLY WINDS ASSOCIATED WITH THE FROPA SINCE
THIS TERMINAL WILL BE CLOSER TO THE STRONGER CORE OF SFC-0.5 KM WINDS.
OTHERWISE, WINDS WILL SHIFT FROM THE SOUTH TO THE NORTH BY MID MORNING.
VFR CIGS EXPECTED THROUGH THE TAF PD. CONVECTION LOOKS TO REMAIN AWAY
FROM THE TERMINALS DUE TO STRONG EML AND RELATED CAPPING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 86 59 86 60 / 0 20 20 10
GCK 83 57 85 58 / 0 10 10 10
EHA 85 57 85 59 / 0 10 10 20
LBL 88 61 87 61 / 0 20 20 20
HYS 83 58 86 57 / 0 10 10 10
P28 91 65 88 63 / 0 30 30 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...SUGDEN
SHORT TERM...SUGDEN
LONG TERM...BURGERT
AVIATION...SUGDEN
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
805 PM EDT MON JUN 11 2012
.SYNOPSIS...
A COLD FRONT WILL BRING SHOWERS AND A CHANCE FOR THUNDERSTORMS
TONIGHT INTO TUESDAY. HIGH PRESSURE IS THEN EXPECTED TO BRING DRY
WEATHER THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TUESDAY/...
RADAR LOOP SHOWS WIDELY SCATTERED SHOWERS DEVELOPING OVER RLX THE
PAST FEW HOURS AND SLOWLY MOVING NORTHWARD. LATEST HRRR AND RAP MODELS
SUGGEST MORE SCATTERED SHOWERS TO DEVELOP TONIGHT BEFORE TAPERING
OFF IN THE MID MORNING HOURS. THUS HAVE INCREASED POPS SLIGHTLY TO
INCLUDE MORE CATEGORICAL AREAS TONIGHT. KEPT ONLY SLIGHT CHANCE OF
THUNDER TONIGHT AS INSTABILITY REMAINS MINIMAL AND CIN BEGINNING TO
FORM OVER THE REGION.
COLD FRONT WILL THEN PASS ACROSS THE REGION TUESDAY AFTERNOON.
SPC HAS CONTINUED TO INCLUDE THE AREA AS A `SEE TEXT` MENTION IN
THE DAY 2 CONVECTIVE OUTLOOK. APPEARS THAT MODERATE INSTABILITY
WILL BE PRESENT...BUT ONLY LOW VALUES OF WIND SHEAR WILL BE
PRESENT. AT THIS POINT...APPEARS AS IF THERE WILL ONLY BE A
MINIMAL CHANCE FOR SEVERE WEATHER.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
A CHANCE OF STORMS REMAINS EAST OF I-79 TUESDAY NIGHT...BUT ONLY
THE RIDGES SHOULD HAVE A CHANCE FOR PRECIPITATION AFTER MIDNIGHT.
BY WEDNESDAY MORNING HIGH PRESSURE WILL BE CENTERED OVER LOWER
MICHIGAN...AND THE HIGH WILL DRIFT INTO QUEBEC THROUGH THE REST OF
THE PERIOD. WITH LAKE ERIE TEMPERATURES STILL IN THE 60S AND
NORTHERLY WINDS WEDNESDAY AND WEDNESDAY NIGHT...TEMPERATURES WILL
BE A FEW DEGREES BELOW NORMAL DURING THAT TIME. AS WINDS SHIFT TO
THE EAST FOR THURSDAY...HIGHS WILL RISE BY A FEW DEGREES.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
BLEND OF RECENT ECMWF AND NAEFS MODEL OUTPUT SHOW UPPER LEVEL RIDGE
BUILDING ACROSS THE EASTERN U.S. THIS PERIOD, AS UPPER LEVEL
TROUGHING IS PROJECTED ACROSS THE WESTERN U.S.
HENCE EXPECT THE UPPER OHIO VALLEY TO BE DRY THROUGH THE WEEKEND
WITH TEMPERATURES EACH DAY SLIGHTLY WARMER THAN THE PREVIOUS. BLEND
OF GFS AND ECMWF MOS SHOW TEMPERATURES FRIDAY TO BE NEAR NORMAL,
THEN GRADUALLY WARMING TO VALUES 5 TO 8 DEGREES WARMER THAN NORMAL
SUNDAY AND MONDAY.
BY EARLY NEXT WEEK, THE SURFACE HIGH CENTER COULD BE OFFSHORE,
BECOMING WHAT IS TERMED A BERMUDA HIGH, WHICH WOULD ALLOW WEAK
LOWLEVEL SOUTHERLY WINDS TO BRING INCREASING HUMIDITY TO THE UPPER
OHIO VALLEY. THIS WOULD PROMOTE A SLIGHT CHANCE OF LATE DAY
INSTABILITY THUNDERSTORMS STARTING MONDAY OR TUESDAY.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
SCATTERED RAIN SHOWERS CONTINUE ACROSS THE FORECAST AREA THIS
EVENING WITH LITTLE RISK OF THUNDER. GENERAL VFR CONDITIONS CAN
BE EXPECTED OVERNIGHT. OCCASIONAL MVFR CONDITIONS ARE POSSIBLE IN
THE RAIN SHOWERS BEFORE MIDNIGHT. A DRY SLOT AHEAD OF THE FRONTAL
SHOWERS WILL BRING A BREAK IN THE SHOWERS IN THE EARLY MORNING...
BUT WITH THE COLD FRONT MOVING INTO EASTERN OHIO SHOWERS CAN BE
EXPECTED AHEAD OF THE FRONT TUESDAY MORNING. RAINFALL AMOUNTS HAVE BEEN
GENERALLY LIGHT THIS EVENING...REDUCING THE RISK OF MORNING FOG
AND STRATUS.
WITH THE COLD FRONT PUSHING EAST OF THE DISTRICT BY LATE AFTERNOON...THE
RISK OF SHOWERS WILL DIMINISH INTO THE EVENING HOURS. SURFACE
WINDS WILL BE MAINLY FROM THE SOUTH AT ABOUT 10 KTS THROUGH
TUESDAY MORNING, WITH GUSTS TO 20 KTS POSSIBLE BEHIND THE FRONT
LATER TUESDAY AFTERNOON.
.OUTLOOK...TUESDAY NIGHT THROUGH SATURDAY...
EXCEPT FOR POSSIBLE RESTRICTIONS EARLY WEDNESDAY MORNING IF FOG
DEVELOPS, POST FRONTAL DRYING AND ENSUING HIGH PRESSURE SUBSIDENCE
WILL PROMOTE VFR INTO THE WEEKEND.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
821 PM EDT MON JUN 11 2012
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 419 PM EDT MON JUN 11 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A FAIRLY DEEP TROF AND
ASSOC STRONG SHORTWAVE MOVING FM ND INTO NW MN. THE EASTWARD
MOVEMENT OF THIS SHORTWAVE IS HELPING TO SLOWLY PUSH A SFC COLD
FRONT ACROSS WRN UPPER MI THIS AFTERNOON. LATEST 19Z SFC
PLOT/ANALYSIS SHOWS THE FRONT IS ALONG A CRYSTAL FALLS-MICHIGAMME
LINE. ALTHOUGH 12Z MODEL SNDGS INDICATE IN EXCESS OF 1000 J/KG
MLCAPE WITH T/TD OF 82/63...VIS SATELLITE LOOP SHOWS LITTLE DVLPMT
TO CU FIELD UPSTREAM OVER CENTRAL UPPER MI OR IMMEDIATELY UPSTREAM
OVER NRN WI. SUSPECT THAT DRY ALOFT MOVING IN AHEAD OF THE SHORTWAVE
AS NOTED ON VERY DRY 12Z KMPX SNDGS MAY BE INHIBITING CU DVLPMT OVER
THE FCST AREA.
TONIGHT...GIVEN LACK OF CU DVLPMT ON VIS SATELLITE MAY END UP
EVENTUALLY HAVING TO BACK OFF ON POPS TO SLIGHT CHC OVER CENTRAL AND
ERN COUNTIES FOR THIS EVENING AHEAD OF APPROACHING FRONT. IF SOME
CONVECTION IS ABLE TO FIRE ALONG THE FRONT...THERE IS A CHANCE FOR
AN ISOLATED STRONG TO SVR STORM GIVEN THE INSTABILITY AND DEEP LAYER
SHEAR GREATER THAN 40 KTS OVER THE AREA. RELUCTANT TO PULL POPS OUT
COMPLETELY SINCE FRONT IS STILL APPROACHING BUT CHC OF PCPN IS
LOOKING MORE AND MORE DOUBTFUL THIS EVENING OVER CENTRAL AND ERN
CWA. MODEL SNDGS INDICATE WEST WINDS ARE EXPECTED TO PICK UP BEHIND
THE FRONT THIS EVENING ESPECIALLY OVER THE KEWEENAW PENINSULA WHERE
PASSAGE OF SECONDARY COLD FRONT AND INCREASING MIXING/INSTABILITY
WITH COLDER AIR COMING IN MAY PRODUCE GUSTS TO 40 MPH. LOOK FOR LOWS
TO REACH INTO THE MID 40S WEST TO MID 50S SOUTH CENTRAL AND EAST.
TUESDAY...THE 500MB TROUGH AXIS WILL MOVE ACROSS THE AREA MIDDAY
ALONG WITH THE 8H THERMAL TROF AS 850 MB TEMPS LOWER TO AROUND 0C.
WITH GOOD CAA IN THE WNW FLOW OVER THE AREA. WITH LIMITED MIXING
ALONG THE LAKE SUPERIOR SHORE EXPECT HIGHS IN THE LOWER TO MID 50S
WHILE DEEPER SOUTH CENTRAL WILL YIELD HIGHS IN THE LOWER TO MID 60S.
INCREASINGLY ANTICYCLONIC SFC-850 MB FLOW AND RDGG BUILDING IN FROM
THE WEST SHOULD SCOUR OUT LOW CLOUDS FROM WEST TO EAST IN THE
AFTERNOON.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 419 PM EDT MON JUN 11 2012
THE SFC HIGH SHOULD BE DIRECTLY OVERHEAD FROM 00-06Z
WEDNESDAY...BEFORE SHIFTING OFF TO QUEBEC WEDNESDAY AFTERNOON INTO
THURSDAY. SIMILAR TO A FEW DAYS AGO...WE WILL MONITOR THE
DEVELOPMENT OF AN ELONGATED SFC LOW STRETCHING FROM S CENTRAL CANADA
THROUGH THE CO ROCKIES.
FROST WILL REMAIN POSSIBLE TUESDAY NIGHT/WEDNESDAY MORNING...WITH
TEMPS BOTTOMING OUT 31-36F INLAND FROM THE GREAT LAKES AS WINDS GO
NEARLY CALM AND CLOUDS DISSIPATE.
WEDNESDAY WILL LIKELY BE A BIT DRIER THAN ORIGINALLY THROUGH...WITH
MIXED DEW POINTS IN THE MID 20S BY 18Z. THIS SCENARIO WOULD RESULT
IN MIN RH VALUES NEAR 20 PERCENT OVER THE WEST HALF OF UPPER
MI...AND 25-30 PERCENT EAST. EXPECT THE RETURN OF LIGHT/SOUTHERLY
FLOW AS THE HIGH SHIFTS ACROSS LAKE HURON AND STRETCHES THROUGH
QUEBEC...STILL BELOW 15MPH. DID PUSH THE FCST CLOSER TO THESE LOWEST
VALUES.
THE ELONGATED SFC LOW STRETCHING FROM SOUTHERN SASKATCHEWAN/MANITOBA
THROUGH THE DAKOTAS AND E CO/NM THURSDAY MORNING WILL CONTINUE TO
REMAIN NEARLY STEADY. ALTHOUGH THURSDAY SHOULD BE WARMER...WITH
INCREASED SOUTHERLY WINDS /20-35KTS BETWEEN THE SFC AND
850MB/...MOISTURE SHOULD BE ON THE INCREASE AS WELL. MIN RH VALUES
COULD STILL NEAR 30 PERCENT OVER PORTIONS OF INTERIOR W UPPER MI BY
LATE MORNING/EARLY AFTERNOON.
THE FCST FOR SUNDAY MONDAY REMAINS VERY UNCERTAIN...SO DID NOT GO
TOO FAR IN DEPTH WITH ADJUSTMENTS FOR THAT PERIOD. THE WESTERN SFC
LOW WILL BE LOCATED SOMEWHERE BETWEEN NWS ONTARIO AND MN BY 12Z
MONDAY...WITH THE TRAILING COLD FRONT STILL REMAINING TO OUR W BY
THE END OF THE DAY. THE RESULT SHOULD BE ANOTHER ROUND OF WARM/HOT
WEATHER SATURDAY THROUGH MONDAY...AS S WINDS REMAIN STEADY AND 850MB
TEMPS RISE AGAIN TO 16 TO 20C.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 820 PM EDT MON JUN 11 2012
ISOLD SHRA AND POSSIBLY A TS OVER CNTRL UPPER MI THIS EVENING WILL
END WITH THE LOSS OF DAYTIME HEATING. WITH ONLY WIDELY SEPARATED
CONVECTION EXPECTED...DID NOT INCLUDE TSRA AT KSAW. WEST WINDS WILL
BECOME BECOME GUSTY...ESPECIALLY AT KCMX...BEHIND A SECONDARY COLD
FRONT MOVING THROUGH THE REGION. LOOKING UPSTREAM...MVFR CIGS COULD
DEVELOP OVERNIGHT AT KIWD AND KCMX AND THEN LATE TUE MORNING AT KSAW
WITH PASSAGE OF SECONDARY COLD FRONT. ANY MVFR CIGS SHOULD LIFT
DURING THE AFTERNOON AS DRIER AIR MOVES IN. &&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 419 PM EDT MON JUN 11 2012
LOW PRESSURE ACROSS HUDSON BAY WILL KEEP A TROUGH ACROSS LS THIS
EVENING...AHEAD OF HIGH NEARING FROM THE WEST. EXPECT THE HIGH OVER
MINNESOTA TUESDAY MORNING TO PUSH ACROSS THE UPPER GREAT LAKES
TUESDAY AFTERNOON THROUGH WEDNESDAY...BEFORE EXITING ACROSS QUEBEC
WEDNESDAY NIGHT. W-NW GUSTS OF 30 TO POSSIBLY 30KTS WILL SLIDE IN
OVERNIGHT AND LINGER THROUGH THE DAY TUESDAY. A RIDGE WILL REMAIN
ACROSS LS THROUGH SATURDAY...AS AN ELONGATED AREA OF LOW PRESSURE
ORGANIZES ACROSS THE CENTRAL AND NORTHERN PLAINS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...KF
AVIATION...JLB
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
142 PM EDT SUN JUN 10 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 507 AM EDT SUN JUN 10 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A RATHER DEEP TROF FOR
EARLY JUNE OVER THE NRN ROCKIES WITH DOWNSTREAM RIDGE OVER THE
UPPER MISSISSIPPI VALLEY. LOW-LEVEL JET AHEAD OF THE TROF HAS BEEN
SUPPORTING ACTIVE CLUSTERS OF TSRA OVER NRN ONTARIO DURING THE
NIGHT. INCREASINGLY CAPPED AIRMASS TO THE S AS EVIDENT COMPARING 00Z
KINL SOUNDING TO KMPX SOUNDING WILL ENSURE THAT ANY PERSISTENT
CONVECTION REMAINS N OF THE AREA THRU THE MORNING. OF NOTE ON
UPSTREAM 00Z KMPX/KDVN SOUNDINGS IS NOT ONLY THE CAPPED AIR MASS BUT
THE VERY DRY AIR IN THE LOW/MID LEVELS. AS A RESULT...QUITE A LARGE
AREA ACROSS IA/SRN WI/NRN IL HAD SFC DWPTS MIX OUT INTO THE 40S
YESTERDAY AFTN. WITH THE DRY AIR ADVECTING TO UPPER MI TODAY...WILL
GO AT OR BLO THE LOWEST GUIDANCE FOR AFTN DWPTS (50 TO 55F) OVER
ROUGHLY THE W HALF WHICH WILL HAVE DEEPEST MIXING. E IS A LITTLE
MORE UNCERTAIN DUE TO MARINE LAYER OFF LAKE MI WORKING TO KEEP
MIXING DEPTHS LWR. WILL OPT TO HOLD DWPTS TO THE UPPER 50S/AROUND 60
NEAR LAKE MI LOWERING TO THE MID 50S TOWARD LAKE SUPERIOR. WITH
THE DRY COLUMN...FCST SOUNDINGS SUGGEST POTENTIAL TO MIX ALL THE WAY
TO 750-700MB. KMPX/KDVN SOUNDINGS SHOWED MIXING HEIGHTS AT AROUND
800MB YESTERDAY. UTILIZING THAT HEIGHT ON FCST SOUNDINGS YIELDS MAX
TEMPS GENERALLY IN THE LWR 90S AWAY FROM LAKE MI INFLUENCE. IF
SOMEHOW MIXING DEPTH DID REACH 750-700MB...TEMPS WOULD TOP OUT IN
THE MID/UPPER 90S. WITH MIXED LAYER WINDS 25-30KT...THERE WILL BE
GUSTY S WINDS TODAY TO 25-30MPH...AND THUS DOWNSLOPE LOCATIONS SUCH AS
ONTONAGON AND BARAGA WILL LIKELY BE WARMEST. WILL GO WITH HIGHS UP
TO 94F IN THOSE AREAS. S WIND NOT AS FAVORABLE AS A SW WIND FOR PEAK
HEAT IN MARQUETTE...BUT TEMPS SHOULD STILL BE ABLE TO TOP 90F THERE.
DRY/CAPPED AIR MASS OBVIOUSLY ARGUES FOR DRY WEATHER TODAY...AND IN
FACT THERE SHOULD BE VERY LITTLE IF ANY CLOUDINESS.
TONIGHT...MID/UPPER TROF MOVES E WITH AXIS REACHING ERN DAKOTAS/WRN
MN BY MON MORNING. FOR SUMMER...IMPRESSIVE 12HR 500MB HEIGHT FALLS
UPWARDS OF AROUND 150M SHIFT NE INTO NRN ONTARIO BY MON MORNING IN
ASSOCIATION WITH ONE VORT MAX MOVING THRU THE TROF. WITH BEST HEIGHT
FALLS PASSING WELL TO THE NW OF HERE AND ASSOCIATED SFC COLD FRONT
ARRIVING LATE TONIGHT/MON MORNING DURING DIURNAL MIN...CONVECTION
WILL LIKELY BEGIN TO STRUGGLE AS IT ARRIVES IN UPPER MI. AT THIS
POINT...CHC POPS WITH A NARROW RIBBON OF LIKELY POPS SPREADING INTO
THE W OVERNIGHT STILL LOOKS ON TRACK. NAM SHOWS MLCAPE ONLY UPWARDS
OF 400 J/KG SPREADING INTO WRN UPPER MI TONIGHT WITH THE GFS JUST A
FEW HUNDRED HIGHER. ALTHOUGH INCREASING DEEP LAYER SHEAR IN EXCESS
OF 30KT OVERSPREADS THE RIBBON OF INSTABILITY...THE INSTABILITY
PROBABLY WON`T BE ENOUGH TO SUPPORT SVR. IT WILL BE A VERY WARM
NIGHT AHEAD OF THE FRONT WITH 60S/AROUND 70F GENERALLY THE RULE. SOME
COOLING WILL OCCUR LATE OVER THE W AS FRONT PASSES AND WINDS TAKE ON
A COMPONENT OFF THE LAKE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 507 AM EDT SUN JUN 10 2012
THE PERIOD STARTS 12Z MON WITH A 500MB SHORTWAVE TROUGH AXIS FROM
MANITOBA TO ERN SD. THE CORRESPONDING 990MB SFC LOW WILL BE OVER FAR
NRN ONTARIO...WITH A TROUGH/COLD FRONT OVER WCENTRAL UPPER MI. THERE
WILL ALSO BE A SECONDARY SFC TROUGH/COLD FRONT EXTENDING BACK
BENEATH THE MID LEVEL TROUGH ACROSS THE SD/ND/MN BORDERS. MODELS ARE
IN GOOD AGREEMENT ON THE TIMING OF THE FRONT AND OTHER FEATURES WITH
THIS SYSTEM.
EXPECT PRECIP TO BE ONGOING ALONG THE FRONT MON MORNING...BUT CAPE
WILL BE SKINNY AND BELOW 500J/KG SO NO SEVERE CONVECTION IS
EXPECTED...AND PRECIP SHOULD BE CONFINED TO RIGHT ALONG THE FRONT AS
MAIN UPPER SUPPORT IS WELL TO THE W AND THERE WILL BE A CAP IN
PLACE. THIS COLD FRONT WILL WASH OUT AS IT MOVES E...BUT THE
SECONDARY COLD FRONT WILL CATCH UP AND MERGE WITH THE FIRST OVER ERN
UPPER MI BY 00Z TUE. BEHIND THE FIRST FRONT...MUCH DRIER AIR WILL
MOVE INTO WRN UPPER MI...SO I WOULD NOT EXPECT ANOTHER ROUND OF
PRECIP OVER THE W WITH THE SECOND FRONT. THE BEST CHANCE OF
WIDESPREAD PRECIP LOOKS TO BE OVER THE ERN HALF OF THE U.P. AS THE
TWO TROUGHS/FRONT MERGE AND THE RIGHT ENTRANCE REGION OF AN UPPER
JET MOVE OVER. PWATS WILL BE AROUND 200 PERCENT OF NORMAL SO SOME
HEAVY RAIN WILL BE POSSIBLE. CAPE VALUES STILL DO NOT LOOK
IMPRESSIVE...EVEN AS SFC TEMPS CLIMB INTO THE UPPER 70S TO UPPER
80S...DUE TO CAPPING AND DRY AIR AND THE FACT THAT THE COLDER MID
LEVELS ARE STILL TO THE W. STILL COULD SEE SOME STRONGER STORMS IN
THE EVENING OVER THE E...WITH THE PRIMARY THREAT BEING STRONG WINDS
GIVEN WEAK SHEAR AND LOW CAPE.
THE WARM TEMPERATURES MON WILL NOT LAST INTO THE REST OF THE WEEK.
THE 500MB TROUGH AXIS MOVES OVER THE CENTRAL CWA BY 18Z
TUE...DROPPING 850MB TEMPS TO AROUND 0-2C WITH NORTHWEST LOW LEVEL
WINDS. THIS LEADS TO HIGH TEMPS IN THE 50S ALONG LAKE SUPERIOR...AND
IN THE 60S INLAND. DRY SFC HIGH PRESSURE WILL BE WORKING IN FROM THE
SW TUE...LEADING TO MOSTLY SUNNY SKIES. WITH THE SFC HIGH OVERHEAD
TUE NIGHT AFTER A COOL DAY TUE...WENT WITH LOWER END OF GUIDANCE ON
TEMPS. THERE IS POTENTIAL FOR FRONT INLAND TUE NIGHT.
THE SFC HIGH WILL REMAIN OVER THE CWA WED...AS 850MB TEMPS INCREASE
UP TO A CWA AVG OF 9C BY 00Z THU. EXPECT HIGH TEMPS IN THE 60S AND
LOW 70S. MOVES ARE SHOWING POTENTIAL FOR A WEAK SHORTWAVE TROUGH TO
MOVE IN FROM THE W LATE WED INTO WED NIGHT...GENERATING SOME
SMATTERS OF PRECIP ACROSS THE REGION. CONFIDENCE IS LOW IN ANY GIVEN
SOLUTION FOR THE PRECIP DURING THIS TIME...SO WILL CONTINUE TO USE
CONSENSUS OF MODELS FOR POPS/QPF.
EXPECT A GENERAL WARMING TREND THU THROUGH SAT AS SLY FLOW INCREASES
AHEAD OF THE NEXT SIGNIFICANT SYSTEM DEPICTED BY MODELS. MODELS SHOW
A MID LEVEL SHORTWAVE TROUGH MOVING INTO THE NRN PLAINS
STATES...BRINGING A SFC TROUGH TO JUST W OF THE CWA BY 00Z NEXT SUN.
THIS LEAVES THE CWA MOSTLY DRY UNTIL SATURDAY...WHEN SOME PRECIP MAY
BE MOVING INTO THE W THROUGH THE DAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 141 PM EDT SUN JUN 10 2012
VFR CONDITIONS WILL PERSIST AT ALL SITES THROUGH THIS EVENING. A
SCATTERED CU FIELD HAS DEVELOPED EARLY THIS AFTERNOON...ESPECIALLY
AT IWD...BUT SHOULD DISSIPATE WITH LOSS OF HEATING. ONCE DECOUPLING
OCCURS TONIGHT...LLWS WILL DEVELOP AT ALL SITES. EXPECT UPWARDS OF
40KTS OF SHEAR OVER THE LOWEST 1 TO 1.5KFT...EVEN THROUGH WINDS STAY
UP AT THE SURFACE. A COLD FRONT WILL USHER IN SHOWERS AND POSSIBLY
THUNDERSTORMS LATE TONIGHT AT IWD. THE FRONT WILL CONTINUE EASTWARD
THROUGH CMX MONDAY MORNING...AND SAW LATE MONDAY MORNING AND EARLY
AFTERNOON. CONFIDENCE IS FAIRLY GOOD THAT THUNDER IS POSSIBLE AT IWD
AND SAW...BUT NOT HIGH ENOUGH TO PUT IT IN THE TAF. BEST CHANCE OF
HIGHER TSRA COVERAGE WILL BE AT SAW. WITH THE FRONT AND
PRECIP...MVFR CIGS AND VIS COULD BE POSSIBLE AT TIMES...BUT ONLY
TEMPORARILY. BEHIND THE COLD FRONT...CLOUDS CLEAR OUT AS DRY AIR
MOVES IN. WINDS COULD BECOMING GUSTY AND PICK UP QUICKLY BEHIND THE
FRONT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 507 AM EDT SUN JUN 10 2012
ALTHOUGH NOT ALWAYS EASY TO SEE ON SATELLITE IMAGERY AT NIGHT...IT
APPEARS THAT FOG OVER PORTIONS OF WESTERN AND NORTHERN LAKE SUPERIOR
IS DIMINISHING AND IS NOW CONFINED CLOSE TO THE MN SHORE AND AROUND
ISLE ROYALE. WITH WINDS OVER THE LAKE BECOMING MOSTLY SOUTHERLY AND
SOME DRIER AIR ADVECTING NORTHWARD...FOG MAY BE GONE BY MID AFTN.
SHOWERS AND POSSIBLE THUNDERSTORMS MAY MOVE ACROSS LAKE SUPERIOR
LATE THIS EVENING THRU MON AFTN. IT`S POSSIBLE FOG MAY REDEVELOP FOR
A TIME IF RAINFALL DOES OCCUR OVER THE LAKE.
AHEAD OF AN APPROACHING TROF/COLD FRONT...LIGHT NORTHEASTERLY WINDS
OVER FAR WRN LAKE SUPERIOR WILL EVENTUALLY SHIFT TO THE S BY LATE
AFTN. ACROSS THE REST OF THE LAKE...SOUTHERLY WINDS WILL GENERALLY
INCREASE TO 15-25KT TODAY AND TONIGHT. OVER THE E HALF OF LAKE
SUPERIOR...THE HIGHEST OBSERVING PLATFORMS MAY SEE GUSTS TO AROUND
30KT THIS AFTN/TONIGHT. SOUTHWESTERLY WINDS WILL DIMINISH MON AHEAD
OF THE NEXT TROF WHICH PASSES MON NIGHT. THE ARRIVAL OF COLDER AIR
WILL BOOST W/NW WINDS TO 15-25KT MON NIGHT THRU TUE MORNING. WINDS
WILL DIMINISH TO UNDER 15KT TUE NIGHT AS HIGH PRES ARRIVES. WINDS
WILL THEN LIKELY STAY MOSTLY UNDER 15KT THRU THU AS HIGH PRES RIDGE
REMAINS IN THE AREA.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...TK
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
726 AM EDT SUN JUN 10 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 507 AM EDT SUN JUN 10 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A RATHER DEEP TROF FOR
EARLY JUNE OVER THE NRN ROCKIES WITH DOWNSTREAM RIDGE OVER THE
UPPER MISSISSIPPI VALLEY. LOW-LEVEL JET AHEAD OF THE TROF HAS BEEN
SUPPORTING ACTIVE CLUSTERS OF TSRA OVER NRN ONTARIO DURING THE
NIGHT. INCREASINGLY CAPPED AIRMASS TO THE S AS EVIDENT COMPARING 00Z
KINL SOUNDING TO KMPX SOUNDING WILL ENSURE THAT ANY PERSISTENT
CONVECTION REMAINS N OF THE AREA THRU THE MORNING. OF NOTE ON
UPSTREAM 00Z KMPX/KDVN SOUNDINGS IS NOT ONLY THE CAPPED AIR MASS BUT
THE VERY DRY AIR IN THE LOW/MID LEVELS. AS A RESULT...QUITE A LARGE
AREA ACROSS IA/SRN WI/NRN IL HAD SFC DWPTS MIX OUT INTO THE 40S
YESTERDAY AFTN. WITH THE DRY AIR ADVECTING TO UPPER MI TODAY...WILL
GO AT OR BLO THE LOWEST GUIDANCE FOR AFTN DWPTS (50 TO 55F) OVER
ROUGHLY THE W HALF WHICH WILL HAVE DEEPEST MIXING. E IS A LITTLE
MORE UNCERTAIN DUE TO MARINE LAYER OFF LAKE MI WORKING TO KEEP
MIXING DEPTHS LWR. WILL OPT TO HOLD DWPTS TO THE UPPER 50S/AROUND 60
NEAR LAKE MI LOWERING TO THE MID 50S TOWARD LAKE SUPERIOR. WITH
THE DRY COLUMN...FCST SOUNDINGS SUGGEST POTENTIAL TO MIX ALL THE WAY
TO 750-700MB. KMPX/KDVN SOUNDINGS SHOWED MIXING HEIGHTS AT AROUND
800MB YESTERDAY. UTILIZING THAT HEIGHT ON FCST SOUNDINGS YIELDS MAX
TEMPS GENERALLY IN THE LWR 90S AWAY FROM LAKE MI INFLUENCE. IF
SOMEHOW MIXING DEPTH DID REACH 750-700MB...TEMPS WOULD TOP OUT IN
THE MID/UPPER 90S. WITH MIXED LAYER WINDS 25-30KT...THERE WILL BE
GUSTY S WINDS TODAY TO 25-30MPH...AND THUS DOWNSLOPE LOCATIONS SUCH AS
ONTONAGON AND BARAGA WILL LIKELY BE WARMEST. WILL GO WITH HIGHS UP
TO 94F IN THOSE AREAS. S WIND NOT AS FAVORABLE AS A SW WIND FOR PEAK
HEAT IN MARQUETTE...BUT TEMPS SHOULD STILL BE ABLE TO TOP 90F THERE.
DRY/CAPPED AIR MASS OBVIOUSLY ARGUES FOR DRY WEATHER TODAY...AND IN
FACT THERE SHOULD BE VERY LITTLE IF ANY CLOUDINESS.
TONIGHT...MID/UPPER TROF MOVES E WITH AXIS REACHING ERN DAKOTAS/WRN
MN BY MON MORNING. FOR SUMMER...IMPRESSIVE 12HR 500MB HEIGHT FALLS
UPWARDS OF AROUND 150M SHIFT NE INTO NRN ONTARIO BY MON MORNING IN
ASSOCIATION WITH ONE VORT MAX MOVING THRU THE TROF. WITH BEST HEIGHT
FALLS PASSING WELL TO THE NW OF HERE AND ASSOCIATED SFC COLD FRONT
ARRIVING LATE TONIGHT/MON MORNING DURING DIURNAL MIN...CONVECTION
WILL LIKELY BEGIN TO STRUGGLE AS IT ARRIVES IN UPPER MI. AT THIS
POINT...CHC POPS WITH A NARROW RIBBON OF LIKELY POPS SPREADING INTO
THE W OVERNIGHT STILL LOOKS ON TRACK. NAM SHOWS MLCAPE ONLY UPWARDS
OF 400 J/KG SPREADING INTO WRN UPPER MI TONIGHT WITH THE GFS JUST A
FEW HUNDRED HIGHER. ALTHOUGH INCREASING DEEP LAYER SHEAR IN EXCESS
OF 30KT OVERSPREADS THE RIBBON OF INSTABILITY...THE INSTABILITY
PROBABLY WON`T BE ENOUGH TO SUPPORT SVR. IT WILL BE A VERY WARM
NIGHT AHEAD OF THE FRONT WITH 60S/AROUND 70F GENERALLY THE RULE. SOME
COOLING WILL OCCUR LATE OVER THE W AS FRONT PASSES AND WINDS TAKE ON
A COMPONENT OFF THE LAKE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 507 AM EDT SUN JUN 10 2012
THE PERIOD STARTS 12Z MON WITH A 500MB SHORTWAVE TROUGH AXIS FROM
MANITOBA TO ERN SD. THE CORRESPONDING 990MB SFC LOW WILL BE OVER FAR
NRN ONTARIO...WITH A TROUGH/COLD FRONT OVER WCENTRAL UPPER MI. THERE
WILL ALSO BE A SECONDARY SFC TROUGH/COLD FRONT EXTENDING BACK
BENEATH THE MID LEVEL TROUGH ACROSS THE SD/ND/MN BORDERS. MODELS ARE
IN GOOD AGREEMENT ON THE TIMING OF THE FRONT AND OTHER FEATURES WITH
THIS SYSTEM.
EXPECT PRECIP TO BE ONGOING ALONG THE FRONT MON MORNING...BUT CAPE
WILL BE SKINNY AND BELOW 500J/KG SO NO SEVERE CONVECTION IS
EXPECTED...AND PRECIP SHOULD BE CONFINED TO RIGHT ALONG THE FRONT AS
MAIN UPPER SUPPORT IS WELL TO THE W AND THERE WILL BE A CAP IN
PLACE. THIS COLD FRONT WILL WASH OUT AS IT MOVES E...BUT THE
SECONDARY COLD FRONT WILL CATCH UP AND MERGE WITH THE FIRST OVER ERN
UPPER MI BY 00Z TUE. BEHIND THE FIRST FRONT...MUCH DRIER AIR WILL
MOVE INTO WRN UPPER MI...SO I WOULD NOT EXPECT ANOTHER ROUND OF
PRECIP OVER THE W WITH THE SECOND FRONT. THE BEST CHANCE OF
WIDESPREAD PRECIP LOOKS TO BE OVER THE ERN HALF OF THE U.P. AS THE
TWO TROUGHS/FRONT MERGE AND THE RIGHT ENTRANCE REGION OF AN UPPER
JET MOVE OVER. PWATS WILL BE AROUND 200 PERCENT OF NORMAL SO SOME
HEAVY RAIN WILL BE POSSIBLE. CAPE VALUES STILL DO NOT LOOK
IMPRESSIVE...EVEN AS SFC TEMPS CLIMB INTO THE UPPER 70S TO UPPER
80S...DUE TO CAPPING AND DRY AIR AND THE FACT THAT THE COLDER MID
LEVELS ARE STILL TO THE W. STILL COULD SEE SOME STRONGER STORMS IN
THE EVENING OVER THE E...WITH THE PRIMARY THREAT BEING STRONG WINDS
GIVEN WEAK SHEAR AND LOW CAPE.
THE WARM TEMPERATURES MON WILL NOT LAST INTO THE REST OF THE WEEK.
THE 500MB TROUGH AXIS MOVES OVER THE CENTRAL CWA BY 18Z
TUE...DROPPING 850MB TEMPS TO AROUND 0-2C WITH NORTHWEST LOW LEVEL
WINDS. THIS LEADS TO HIGH TEMPS IN THE 50S ALONG LAKE SUPERIOR...AND
IN THE 60S INLAND. DRY SFC HIGH PRESSURE WILL BE WORKING IN FROM THE
SW TUE...LEADING TO MOSTLY SUNNY SKIES. WITH THE SFC HIGH OVERHEAD
TUE NIGHT AFTER A COOL DAY TUE...WENT WITH LOWER END OF GUIDANCE ON
TEMPS. THERE IS POTENTIAL FOR FRONT INLAND TUE NIGHT.
THE SFC HIGH WILL REMAIN OVER THE CWA WED...AS 850MB TEMPS INCREASE
UP TO A CWA AVG OF 9C BY 00Z THU. EXPECT HIGH TEMPS IN THE 60S AND
LOW 70S. MOVES ARE SHOWING POTENTIAL FOR A WEAK SHORTWAVE TROUGH TO
MOVE IN FROM THE W LATE WED INTO WED NIGHT...GENERATING SOME
SMATTERS OF PRECIP ACROSS THE REGION. CONFIDENCE IS LOW IN ANY GIVEN
SOLUTION FOR THE PRECIP DURING THIS TIME...SO WILL CONTINUE TO USE
CONSENSUS OF MODELS FOR POPS/QPF.
EXPECT A GENERAL WARMING TREND THU THROUGH SAT AS SLY FLOW INCREASES
AHEAD OF THE NEXT SIGNIFICANT SYSTEM DEPICTED BY MODELS. MODELS SHOW
A MID LEVEL SHORTWAVE TROUGH MOVING INTO THE NRN PLAINS
STATES...BRINGING A SFC TROUGH TO JUST W OF THE CWA BY 00Z NEXT SUN.
THIS LEAVES THE CWA MOSTLY DRY UNTIL SATURDAY...WHEN SOME PRECIP MAY
BE MOVING INTO THE W THROUGH THE DAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 725 AM EDT SUN JUN 10 2012
VFR CONDITIONS SHOULD PREVAIL AT KIWD/KCMX/KSAW THROUGH THIS FCST
PERIOD. WITH DAYTIME HEATING/DEEP MIXING TODAY...SOUTH WINDS WILL
BECOME GUSTY IN THE 20-30KT RANGE. DEPENDING ON DEGREE OF DECOUPLING
TONIGHT...LLWS WILL BE POSSIBLE AHEAD OF APPROACHING LOW PRES
TROF. KIWD/KSAW ARE MORE LIKELY TO RETAIN GUSTY SFC WINDS AND THUS
PRECLUDE LLWS. SHOWERS AND THUNDERSTORMS ALONG TROF WILL LIKELY BE
DIMINISHING AS THEY MOVE INTO UPPER MI LATER TONIGHT. FOR NOW...
INCLUDED -SHRA ONLY AT KIWD LATE TONIGHT. IF SHRA HOLD TOGETHER...
THEY WOULD REACH KCMX AROUND THE END OF THIS FCST PERIOD AND KSAW
MON MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 507 AM EDT SUN JUN 10 2012
ALTHOUGH NOT ALWAYS EASY TO SEE ON SATELLITE IMAGERY AT NIGHT...IT
APPEARS THAT FOG OVER PORTIONS OF WESTERN AND NORTHERN LAKE SUPERIOR
IS DIMINISHING AND IS NOW CONFINED CLOSE TO THE MN SHORE AND AROUND
ISLE ROYALE. WITH WINDS OVER THE LAKE BECOMING MOSTLY SOUTHERLY AND
SOME DRIER AIR ADVECTING NORTHWARD...FOG MAY BE GONE BY MID AFTN.
SHOWERS AND POSSIBLE THUNDERSTORMS MAY MOVE ACROSS LAKE SUPERIOR
LATE THIS EVENING THRU MON AFTN. IT`S POSSIBLE FOG MAY REDEVELOP FOR
A TIME IF RAINFALL DOES OCCUR OVER THE LAKE.
AHEAD OF AN APPROACHING TROF/COLD FRONT...LIGHT NORTHEASTERLY WINDS
OVER FAR WRN LAKE SUPERIOR WILL EVENTUALLY SHIFT TO THE S BY LATE
AFTN. ACROSS THE REST OF THE LAKE...SOUTHERLY WINDS WILL GENERALLY
INCREASE TO 15-25KT TODAY AND TONIGHT. OVER THE E HALF OF LAKE
SUPERIOR...THE HIGHEST OBSERVING PLATFORMS MAY SEE GUSTS TO AROUND
30KT THIS AFTN/TONIGHT. SOUTHWESTERLY WINDS WILL DIMINISH MON AHEAD
OF THE NEXT TROF WHICH PASSES MON NIGHT. THE ARRIVAL OF COLDER AIR
WILL BOOST W/NW WINDS TO 15-25KT MON NIGHT THRU TUE MORNING. WINDS
WILL DIMINISH TO UNDER 15KT TUE NIGHT AS HIGH PRES ARRIVES. WINDS
WILL THEN LIKELY STAY MOSTLY UNDER 15KT THRU THU AS HIGH PRES RIDGE
REMAINS IN THE AREA.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 8 AM EDT /7 AM CDT/ THIS MORNING FOR
LSZ162-263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION...CORRECTED
NWS MARQUETTE MI
509 AM EDT SUN JUN 10 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 507 AM EDT SUN JUN 10 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A RATHER DEEP TROF FOR
EARLY JUNE OVER THE NRN ROCKIES WITH DOWNSTREAM RIDGE OVER THE
UPPER MISSISSIPPI VALLEY. LOW-LEVEL JET AHEAD OF THE TROF HAS BEEN
SUPPORTING ACTIVE CLUSTERS OF TSRA OVER NRN ONTARIO DURING THE
NIGHT. INCREASINGLY CAPPED AIRMASS TO THE S AS EVIDENT COMPARING 00Z
KINL SOUNDING TO KMPX SOUNDING WILL ENSURE THAT ANY PERSISTENT
CONVECTION REMAINS N OF THE AREA THRU THE MORNING. OF NOTE ON
UPSTREAM 00Z KMPX/KDVN SOUNDINGS IS NOT ONLY THE CAPPED AIR MASS BUT
THE VERY DRY AIR IN THE LOW/MID LEVELS. AS A RESULT...QUITE A LARGE
AREA ACROSS IA/SRN WI/NRN IL HAD SFC DWPTS MIX OUT INTO THE 40S
YESTERDAY AFTN. WITH THE DRY AIR ADVECTING TO UPPER MI TODAY...WILL
GO AT OR BLO THE LOWEST GUIDANCE FOR AFTN DWPTS (50 TO 55F) OVER
ROUGHLY THE W HALF WHICH WILL HAVE DEEPEST MIXING. E IS A LITTLE
MORE UNCERTAIN DUE TO MARINE LAYER OFF LAKE MI WORKING TO KEEP
MIXING DEPTHS LWR. WILL OPT TO HOLD DWPTS TO THE UPPER 50S/AROUND 60
NEAR LAKE MI LOWERING TO THE MID 50S TOWARD LAKE SUPERIOR. WITH
THE DRY COLUMN...FCST SOUNDINGS SUGGEST POTENTIAL TO MIX ALL THE WAY
TO 750-700MB. KMPX/KDVN SOUNDINGS SHOWED MIXING HEIGHTS AT AROUND
800MB YESTERDAY. UTILIZING THAT HEIGHT ON FCST SOUNDINGS YIELDS MAX
TEMPS GENERALLY IN THE LWR 90S AWAY FROM LAKE MI INFLUENCE. IF
SOMEHOW MIXING DEPTH DID REACH 750-700MB...TEMPS WOULD TOP OUT IN
THE MID/UPPER 90S. WITH MIXED LAYER WINDS 25-30KT...THERE WILL BE
GUSTY S WINDS TODAY TO 25-30MPH...AND THUS DOWNSLOPE LOCATIONS SUCH AS
ONTONAGON AND BARAGA WILL LIKELY BE WARMEST. WILL GO WITH HIGHS UP
TO 94F IN THOSE AREAS. S WIND NOT AS FAVORABLE AS A SW WIND FOR PEAK
HEAT IN MARQUETTE...BUT TEMPS SHOULD STILL BE ABLE TO TOP 90F THERE.
DRY/CAPPED AIR MASS OBVIOUSLY ARGUES FOR DRY WEATHER TODAY...AND IN
FACT THERE SHOULD BE VERY LITTLE IF ANY CLOUDINESS.
TONIGHT...MID/UPPER TROF MOVES E WITH AXIS REACHING ERN DAKOTAS/WRN
MN BY MON MORNING. FOR SUMMER...IMPRESSIVE 12HR 500MB HEIGHT FALLS
UPWARDS OF AROUND 150M SHIFT NE INTO NRN ONTARIO BY MON MORNING IN
ASSOCIATION WITH ONE VORT MAX MOVING THRU THE TROF. WITH BEST HEIGHT
FALLS PASSING WELL TO THE NW OF HERE AND ASSOCIATED SFC COLD FRONT
ARRIVING LATE TONIGHT/MON MORNING DURING DIURNAL MIN...CONVECTION
WILL LIKELY BEGIN TO STRUGGLE AS IT ARRIVES IN UPPER MI. AT THIS
POINT...CHC POPS WITH A NARROW RIBBON OF LIKELY POPS SPREADING INTO
THE W OVERNIGHT STILL LOOKS ON TRACK. NAM SHOWS MLCAPE ONLY UPWARDS
OF 400 J/KG SPREADING INTO WRN UPPER MI TONIGHT WITH THE GFS JUST A
FEW HUNDRED HIGHER. ALTHOUGH INCREASING DEEP LAYER SHEAR IN EXCESS
OF 30KT OVERSPREADS THE RIBBON OF INSTABILITY...THE INSTABILITY
PROBABLY WON`T BE ENOUGH TO SUPPORT SVR. IT WILL BE A VERY WARM
NIGHT AHEAD OF THE FRONT WITH 60S/AROUND 70F GENERALLY THE RULE. SOME
COOLING WILL OCCUR LATE OVER THE W AS FRONT PASSES AND WINDS TAKE ON
A COMPONENT OFF THE LAKE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 507 AM EDT SUN JUN 10 2012
THE PERIOD STARTS 12Z MON WITH A 500MB SHORTWAVE TROUGH AXIS FROM
MANITOBA TO ERN SD. THE CORRESPONDING 990MB SFC LOW WILL BE OVER FAR
NRN ONTARIO...WITH A TROUGH/COLD FRONT OVER WCENTRAL UPPER MI. THERE
WILL ALSO BE A SECONDARY SFC TROUGH/COLD FRONT EXTENDING BACK
BENEATH THE MID LEVEL TROUGH ACROSS THE SD/ND/MN BORDERS. MODELS ARE
IN GOOD AGREEMENT ON THE TIMING OF THE FRONT AND OTHER FEATURES WITH
THIS SYSTEM.
EXPECT PRECIP TO BE ONGOING ALONG THE FRONT MON MORNING...BUT CAPE
WILL BE SKINNY AND BELOW 500J/KG SO NO SEVERE CONVECTION IS
EXPECTED...AND PRECIP SHOULD BE CONFINED TO RIGHT ALONG THE FRONT AS
MAIN UPPER SUPPORT IS WELL TO THE W AND THERE WILL BE A CAP IN
PLACE. THIS COLD FRONT WILL WASH OUT AS IT MOVES E...BUT THE
SECONDARY COLD FRONT WILL CATCH UP AND MERGE WITH THE FIRST OVER ERN
UPPER MI BY 00Z TUE. BEHIND THE FIRST FRONT...MUCH DRIER AIR WILL
MOVE INTO WRN UPPER MI...SO I WOULD NOT EXPECT ANOTHER ROUND OF
PRECIP OVER THE W WITH THE SECOND FRONT. THE BEST CHANCE OF
WIDESPREAD PRECIP LOOKS TO BE OVER THE ERN HALF OF THE U.P. AS THE
TWO TROUGHS/FRONT MERGE AND THE RIGHT ENTRANCE REGION OF AN UPPER
JET MOVE OVER. PWATS WILL BE AROUND 200 PERCENT OF NORMAL SO SOME
HEAVY RAIN WILL BE POSSIBLE. CAPE VALUES STILL DO NOT LOOK
IMPRESSIVE...EVEN AS SFC TEMPS CLIMB INTO THE UPPER 70S TO UPPER
80S...DUE TO CAPPING AND DRY AIR AND THE FACT THAT THE COLDER MID
LEVELS ARE STILL TO THE W. STILL COULD SEE SOME STRONGER STORMS IN
THE EVENING OVER THE E...WITH THE PRIMARY THREAT BEING STRONG WINDS
GIVEN WEAK SHEAR AND LOW CAPE.
THE WARM TEMPERATURES MON WILL NOT LAST INTO THE REST OF THE WEEK.
THE 500MB TROUGH AXIS MOVES OVER THE CENTRAL CWA BY 18Z
TUE...DROPPING 850MB TEMPS TO AROUND 0-2C WITH NORTHWEST LOW LEVEL
WINDS. THIS LEADS TO HIGH TEMPS IN THE 50S ALONG LAKE SUPERIOR...AND
IN THE 60S INLAND. DRY SFC HIGH PRESSURE WILL BE WORKING IN FROM THE
SW TUE...LEADING TO MOSTLY SUNNY SKIES. WITH THE SFC HIGH OVERHEAD
TUE NIGHT AFTER A COOL DAY TUE...WENT WITH LOWER END OF GUIDANCE ON
TEMPS. THERE IS POTENTIAL FOR FRONT INLAND TUE NIGHT.
THE SFC HIGH WILL REMAIN OVER THE CWA WED...AS 850MB TEMPS INCREASE
UP TO A CWA AVG OF 9C BY 00Z THU. EXPECT HIGH TEMPS IN THE 60S AND
LOW 70S. MOVES ARE SHOWING POTENTIAL FOR A WEAK SHORTWAVE TROUGH TO
MOVE IN FROM THE W LATE WED INTO WED NIGHT...GENERATING SOME
SMATTERS OF PRECIP ACROSS THE REGION. CONFIDENCE IS LOW IN ANY GIVEN
SOLUTION FOR THE PRECIP DURING THIS TIME...SO WILL CONTINUE TO USE
CONSENSUS OF MODELS FOR POPS/QPF.
EXPECT A GENERAL WARMING TREND THU THROUGH SAT AS SLY FLOW INCREASES
AHEAD OF THE NEXT SIGNIFICANT SYSTEM DEPICTED BY MODELS. MODELS SHOW
A MID LEVEL SHORTWAVE TROUGH MOVING INTO THE NRN PLAINS
STATES...BRINGING A SFC TROUGH TO JUST W OF THE CWA BY 00Z NEXT SUN.
THIS LEAVES THE CWA MOSTLY DRY UNTIL SATURDAY...WHEN SOME PRECIP MAY
BE MOVING INTO THE W THROUGH THE DAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 137 AM EDT SUN JUN 10 2012
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD. WINDS VEERING
MORE SRLY AT CMX SHOULD MINIMIZE FOG POTENTIAL OVERNIGHT. WITH
STRONGER WINDS SLIDING IN OVERHEAD SHOULD SEE LLWS OVERNIGHT AS THE LOW
LEVELS REMAIN DECOUPLED. LATEST VAD WIND PROFILE FROM KMQT RADAR
INDICATES SW WIND AT ABOUT 30KT AT 500FT AGL. WITH DAYTIME HEATING/MIXING
SOUTH WINDS WILL BECOME GUSTY TODAY. STRONGER LLWS IS EXPECTED
THIS EVENING AHEAD OF A COLD FRONT ADVANCING TOWARD THE REGION.
SHOWERS AND THUNDERSTORMS ASSOCIATED WITH THE FRONT SHOULD HOLD OFF
AT IWD TIL AFT 06Z.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 507 AM EDT SUN JUN 10 2012
ALTHOUGH NOT ALWAYS EASY TO SEE ON SATELLITE IMAGERY AT NIGHT...IT
APPEARS THAT FOG OVER PORTIONS OF WESTERN AND NORTHERN LAKE SUPERIOR
IS DIMINISHING AND IS NOW CONFINED CLOSE TO THE MN SHORE AND AROUND
ISLE ROYALE. WITH WINDS OVER THE LAKE BECOMING MOSTLY SOUTHERLY AND
SOME DRIER AIR ADVECTING NORTHWARD...FOG MAY BE GONE BY MID AFTN.
SHOWERS AND POSSIBLE THUNDERSTORMS MAY MOVE ACROSS LAKE SUPERIOR
LATE THIS EVENING THRU MON AFTN. IT`S POSSIBLE FOG MAY REDEVELOP FOR
A TIME IF RAINFALL DOES OCCUR OVER THE LAKE.
AHEAD OF AN APPROACHING TROF/COLD FRONT...LIGHT NORTHEASTERLY WINDS
OVER FAR WRN LAKE SUPERIOR WILL EVENTUALLY SHIFT TO THE S BY LATE
AFTN. ACROSS THE REST OF THE LAKE...SOUTHERLY WINDS WILL GENERALLY
INCREASE TO 15-25KT TODAY AND TONIGHT. OVER THE E HALF OF LAKE
SUPERIOR...THE HIGHEST OBSERVING PLATFORMS MAY SEE GUSTS TO AROUND
30KT THIS AFTN/TONIGHT. SOUTHWESTERLY WINDS WILL DIMINISH MON AHEAD
OF THE NEXT TROF WHICH PASSES MON NIGHT. THE ARRIVAL OF COLDER AIR
WILL BOOST W/NW WINDS TO 15-25KT MON NIGHT THRU TUE MORNING. WINDS
WILL DIMINISH TO UNDER 15KT TUE NIGHT AS HIGH PRES ARRIVES. WINDS
WILL THEN LIKELY STAY MOSTLY UNDER 15KT THRU THU AS HIGH PRES RIDGE
REMAINS IN THE AREA.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 8 AM EDT /7 AM CDT/ THIS MORNING FOR
LSZ162-263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...JLB/ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS GLASGOW MT
914 PM MDT MON JUN 11 2012
.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH WEDNESDAY...
EVENING UPDATE...
MINOR TWEAKS WERE THE NAME OF THE GAME THIS EVENING. THE MOST
SIGNIFICANT CHANGE WAS TO TRY TO GET THE LIGHT RAIN SHOWERS OVER
NORTHERN PHILLIPS COUNTY INTO THE FORECAST POPS AS ACCURATELY
AS POSSIBLE. USED A BLEND OF THE LAST THREE RUNS OF THE HRRR...
SMOOTHED THEM OUT... AND MOVED THE COLUMN OF POPS SOUTH ABOUT 20
MILES TO CAPTURE THE RADAR TREND. SURPRISINGLY... EXTRAPOLATING THE
HRRR ALSO POINTS TOWARD THESE SHOWERS NOT FALLING APART BUT RATHER
CONTINUING ALONG THIS PARALLEL INTO TO DANIELS COUNTY DURING THE
MORNING HOURS. SATELLITE AND MSAS PRESSURE FIELDS SEEM TO INDICATE
THAT SHOWERS WOULD FOLLOW A DEVELOPING MESOSCALE TROUGH ALONG THE
INTERNATIONAL BORDER. SO... LEFT IT IN THE POP FIELDS.
PAID ATTENTION TO THE WIND FIELDS AS WELL BY DOING A BLEND OF HRRR
AND HIRES ARM AND NMM TO CAPTURE THE AFFECTS OF THE INVERSION AND
DRAINAGE FLOWS OVERNIGHT. THIS IN TURN ALLOWED FOR A SLIGHT CHANGE
TO PATTERNS FOR TWEAKING THE OVERNIGHT MINIMUM TEMPERATURE GRID.
GAH
PREVIOUS SHORT TERM DISCUSSION...
A WEAK UPPER RIDGE OVER THE PACIFIC NORTHWEST INTO ALBERTA WILL
MOVE OVER THE NORTHERN ROCKIES TONIGHT INTO TOMORROW. A WEAK
SHORTWAVE WILL UNDERCUT THE UPPER RIDGE ON TUESDAY. ANOTHER
SLIGHTLY STRONGER SHORTWAVE TROUGH WILL ROTATE AROUND THE UPPER
LOW OVER THE GULF OF ALASKA AND MOVE OVER THE NORTHERN ROCKIES
TUESDAY NIGHT INTO WEDNESDAY.
THIS AFTERNOON AND EVENING THE WINDS WILL CONTINUE TO DROP OFF AS
THE PRESSURE GRADIENT RELAXES AS A SURFACE HIGH MOVES IN FROM THE
SOUTHWEST. SO WILL CANCEL THE LAKE WIND ADVISORY WITH THE
AFTERNOON PACKAGE...A FEW HOURS EARLIER THEN EXPECTED. COULD BE
SOME SCATTERED SHOWERS AROUND WITH SOME ISOLATED THUNDERSTORMS
MOVING ACROSS THE REGION THIS EVENING WHICH WAS INDICATED ON THE
LATEST HRRR RUN. THIS ACTIVITY WILL END BEFORE MIDNIGHT SO
DROPPED POPS DOWN TO NOTHING AFTER THAT.
TUESDAY...ADDED SOME SLIGHT CHANCE POPS OVER MY SW ZONES AS THE
WEAK WAVE MOVES ACROSS SOUTHERN MONTANA. MODELS SOUNDING DO SHOW A
SMALL AMOUNT OF ELEVATED CAPE ACROSS THE REGION SO A FEW ISOLATED
STORMS ARE POSSIBLE SO WENT WITH A SLIGHT CHANCE OF THUNDER FOR
TUESDAY AFTERNOON AND EVENING.
TUESDAY NIGHT THROUGH WEDNESDAY...THE SLIGHTLY STRONGER SHORTWAVE
WILL MOVE INTO WESTERN MONTANA WHICH WILL HELP GENERATE SOUTHWEST
FLOW OVER EASTERN MONTANA. THIS WILL HELP TO DESTABILIZE THE MID
LEVELS AHEAD OF THE SHORTWAVE. CAPE VALUES ARE ONCE AGAIN WEAK AND
ELEVATED OTHER THUNDERSTORM PARAMETERS ARE WEAK AS WELL. THE
THINKING AT THIS TIME IS JUST GENERAL THUNDER POSSIBLE FOR
WEDNESDAY AFTERNOON AND EVENING. RSMITH
.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...
THE EXTENDED PERIOD BEGINS WITH AN UPPER LEVEL SHORTWAVE TROUGH
MOVING OVER MONTANA THURSDAY NIGHT. THE ASSOCIATED COLD FRONT
SWINGS ACROSS THE AREA...MEETING MODERATE INSTABILITY...GENERATING
THUNDERSTORMS IN THE EVENING. TIMING IS NOT CERTAIN WITH THIS WAVE
DUE TO DIFFERENCES BETWEEN THE 12Z GFS AND THE 00Z ECMWF. THESE
DIFFERENCES CONTINUE THROUGH THE ENTIRE PERIOD.
ALTHOUGH NOT CERTAIN...THERE APPEARS TO BE A BREAK IN THE ACTION
ON THURSDAY AND FRIDAY WITH A SHORT PERIOD UPPER RIDGE. THIS
RIDGE GETS OVERTAKEN BY THE NEXT UPPER TROUGH LATE FRIDAY. FROM
THIS POINT ON THE MODELS AGREE WITH AN UPPER TROUGH ONLY IN
GENERAL...BUT DIFFER TOTALLY WITH THE EMBEDDED FEATURES. LATE IN
THE SHIFT THE 12Z EC CONTINUES THE DISAGREEMENT WITH THE GFS.
AGREE THE BEST BET IS TO MAINTAIN CHANCE POPS AND COOLER
TEMPERATURES THROUGH THE ENTIRE PERIOD UNTIL BETTER AGREEMENT IS
OBTAINED. SCT
PREVIOUS DISCUSSION...
SHORTWAVE TROUGH EXITS THE AREA WEDNESDAY NIGHT WITH LINGERING
SHOWERS AND THUNDERSTORMS POSSIBLE ESPECIALLY IN THE NORTHEAST.
HIGH PRESSURE SYSTEM AND SHORTWAVE RIDGE WILL BE OVER THE AREA ON
THURSDAY WITH MAINLY DRY WEATHER. THE WESTERN ZONES COULD SEE A
SHOWER OR THUNDERSTORM IN THE AFTERNOON AHEAD OF THE NEXT SYSTEM.
AN UPPER TROUGH WILL BE OVER MONTANA AND NEARBY AREAS OVER THE
WEEKEND AND EARLY NEXT WEEK. THERE ARE DIFFERENCES BETWEEN THE
MODELS ON HOW THE TROUGH WILL BE CONFIGURED...TIMING OF SHORTWAVES
WITHIN THE TROUGH AND WHEN AND WHERE INDIVIDUAL STORMS WILL OCCUR.
NORTHEAST MONTANA WILL SEE RAIN WITH SHOWERS AND THUNDERSTORMS AT
TIMES OVER THE PERIOD BUT MODEL CONFIDENCE IS TOO LOW TO TIME WHEN
RAIN WILL OCCUR AT THIS POINT. PREVIOUS FORECAST IDEA OF A 30 TO
40 POP BROAD-BRUSH LOOKS REASONABLE FOR NOW. FORRESTER
&&
.AVIATION...
12/00Z...VFR CONDITIONS EXPECTED THRU TAF PERIOD. AN UPPER LEVEL RIDGE
WILL MOVE ACROSS NORTHEAST MONTANA TONIGHT WHICH SHOULD END THE
THREAT OF SHOWERS AND REDUCE CLOUD COVER. ON TUESDAY A WEAK
SHORTWAVE TROUGH NUDGES INTO THE NORTHERN ROCKIES LEADING TO THE
POSSIBILITY OF THUNDERSTORMS. ALTHOUGH NORTHEAST MONTANA WILL
DEVELOP WEAK INSTABILITY...THE LACK OF LOCAL DISTURBANCES WILL
DIMINISH THE THREAT OF THUNDERSTORMS. BEST CHANCES LOOK TO BE
TOWARD KGDV AND KSDY LATE IN PERIOD. CONFIDENCE NOT HIGH ENOUGH TO
EVEN MENTION IN TAF AT THIS TIME. WITH A BROAD LEE SURFACE
TROUGH TUESDAY...EXPECT SOUTHWESTERLY WINDS TO REMAIN LESS THAN
15KTS. MOYER/SCT
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
142 PM CDT SUN JUN 10 2012
.UPDATE...
AVIATION... 18Z TAFS FOR KOMA...KLNK...KOFK.
MAIN CHALLENGE WITH THE AVIATION FORECAST IS TIMING THE
THUNDERSTORMS THIS AFTERNOON AND THIS EVENING...AS WELL AS THE
WIND SHIFT AS A COLD FRONT MOVES THROUGH. FRONT IS ALREADY PAST
KOFK SO THE STORM CHANCES THERE ARE MINIMAL. HOWEVER THE FRONT
WILL BE MOVING THROUGH KLNK AND KOMA IN THE 20-21Z TIME FRAME
MAKING THESE TWO TAF SITES VULNERABLE FOR SCATTERED STRONG STORMS.
INCLUDED TEMPO GROUPS TO ACCOUNT FOR THIS SCENARIO. AFTER THE
FRONT MOVES THROUGH AND THE SUNSETS... CHANCE FOR RAIN/STORMS
DIMINISHES GREATLY AND NORTHWEST WINDS WILL ALSO DIMINISH. WINDS
WILL PICK UP AGAIN BY MID MORNING MONDAY BUT VFR CONDITIONS ARE
EXPECTED THEN.
NIETFELD
&&
PREV DISCUSSION... /ISSUED 323 AM CDT SUN JUN 10 2012/
DISCUSSION...
THUNDERSTORM CHANCES TODAY...THEN COOLER TEMPERATURES INTO THE
MIDDLE OF THE WEEK...ARE THE PRIMARY FORECAST CONCERNS.
DEEP MID LEVEL LOW PRESSURE WAS NOTED FROM MONTANA INTO SOUTHERN
CANADA THIS MORNING...WITH STRONG SHORTWAVE ROTATING AROUND SOUTHERN
SIDE AS NOTED ON WATER VAPOR LOOPS. 110KT JET SEGMENT EXTENDING FROM
WYOMING THROUGH EASTERN MONTANA WAS AIDING COMPLEX OF STORMS NOW
MOVING THROUGH NORTHERN SOUTH DAKOTA. COLD FRONT ASSOCIATED WITH
THESE FEATURES EXTENDED FROM SOUTH DAKOTA CONVECTION INTO THE
NEBRASKA PANHANDLE. DESPITE WARM MID LEVEL TEMPERATURES CAPPING
SOUTHWARD DEVELOPMENT...LATEST HRRR MODEL RUNS SUGGEST SOME
SHOWERS WILL BUILD/DEVELOP SOUTH BEHIND FRONTAL BOUNDARY THIS
MORNING. AND IR SATELLITE PICTURES WERE SHOWING SOME MID LEVEL
CLOUD DEVELOPMENT IN THE PANHANDLE...LENDING CREDENCE TO HRRR
PRECIP FORECAST FARTHER SOUTH INTO NEBRASKA.
COLD FRONT WILL MOVE STEADILY SOUTHEAST...ENTERING OUR FAR NORTHWEST
CWA AROUND 15Z BASED ON GFS/HRRR FORECASTS. EXPECT PRECIPITATION TO
REMAIN BEHIND FRONTAL BOUNDARY FOR THE MOST PART THROUGH THE MORNING
HOURS AS CAPPING PROHIBITS WARM SECTOR DEVELOPMENT UNTIL LATER IN
THE AFTERNOON. COLD FRONT SHOULD APPROACH OMAHA TO LINCOLN LINE
AROUND 21Z WHEN RIBBON OF MID 60S DEW POINTS WILL LIE JUST AHEAD OF
BOUNDARY. TAKING INTO ACCOUNT MODELS OVER-FORECASTING DEW
POINTS...SUBJECTIVE SURFACE-BASED CAPES SHOULD BE NEAR 2000 J/KG
ALONG/AHEAD OF COLD FRONT WITH CAP ERODING AS TEMPERATURES REACH THE
85 TO 90 DEGREE RANGE. BULK SHEAR VALUES ARE ONLY MODEST IN OUR AREA
WHERE MID LEVEL WIND FIELDS WILL BE GENERALLY WEAK. BUT INSTABILITY
SHOULD BE SUFFICIENT FOR SOME POTENTIALLY SEVERE HAIL...AND DEW
POINT DEPRESSIONS MAY ALLOW FOR NEAR-SEVERE DOWNBURSTS.
FRONT SHOULD BE MOVING ACROSS THE MISSOURI RIVER BY LATE
AFTERNOON...THEN SWEEPING SOUTHEAST OF THE CWA OVERNIGHT. MOST
CONVECTION SHOULD BE SOUTH OF OUR AREA BY MIDNIGHT...WITH ONLY FAR
SOUTHEAST NEBRASKA AND SOUTHWEST IOWA SEEING RAIN CHANCES AFTER
MIDNIGHT. SIGNIFICANTLY COOLER AND DRIER AIR WILL BEGIN TO FILTER
INTO THE AREA LATE TONIGHT. HAVE LOWS IN THE MID TO UPPER 50S FOR
MOST OF THE AREA. THEN HIGH PRESSURE SETTLING INTO THE PLAINS ON
MONDAY WILL MAINTAIN NORTHWEST LOW LEVEL FLOW...USHERING IN EVEN
COOLER AND DRIER AIR. PLENTY OF SUNSHINE SHOULD PUSH HIGHS BACK
TOWARD 80 THEN...BUT LOWS IN THE LOWER 50S WILL BE COMMON MONDAY
NIGHT.
THE SURFACE HIGH WILL MOVE EAST ON TUESDAY ALLOWING SOUTHEAST WINDS
TO RETURN...AIDED BY DEVELOPING LOW PRESSURE IN THE HIGH PLAINS
AHEAD OF MID LEVEL SHORTWAVE. MODELS HAVE BEEN ADVERTISING
PRECIPITATION WITH THIS WAVE OVER THE LAST SEVERAL DAYS...AND THE
LATEST RUNS ARE NO DIFFERENT. EXPECT PRECIPITATION TO REMAIN WEST
OF OUR AREA DURING THE DAY TUESDAY...BUT SHOULD ROLL INTO
NORTHEAST NEBRASKA OVERNIGHT.
THE REST OF THE WEEK INTO SATURDAY IS BEGINNING TO LOOK MORE
UNSETTLED THAN PREVIOUS FORECASTS. DEVELOPING UPPER TROUGH ALONG THE
WEST COAST IS NOW ADVERTISED TO BE MORE OPEN THAN PREVIOUS MODEL
RUNS...ALLOWING FOR SOUTHWEST FLOW ALOFT TO RULE OVER THE MIDDLE OF
THE COUNTRY. THIS WILL ALLOW DISTURBANCES TO INITIATE RAIN CHANCES
FROM TIME TO TIME...ESPECIALLY FRIDAY INTO SATURDAY. GOING FORECAST
ALREADY HAD SMALL PRECIP CHANCES GOING...THUS WILL ONLY HAVE TO
TWEAK POPS UPWARD A TAD LATE IN THE WEEK.
DERGAN
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS OMAHA/VALLEY NE
639 AM CDT SUN JUN 10 2012
.UPDATE...
&&
.AVIATION...
12Z TAFS FOR KOMA...KLNK...KOFK
MAIN AVIATION CONCERN IS COLD FRONTAL PASSAGE ACROSS ERN NEB THIS
AFTN. LATEST SFC OBS DEPICTING AREA OF LOW PRESSURE IN WRN KS WITH
PRE-FRONTAL INVERTED TROF EXTENDING NEWD INTO ERN SD WITH THE WIND
SHIFT LINE SITUATED FROM KHON TO KGLD. AT THIS POINT...EXPECT
FROPA AT KOFK AROUND 19Z...KOMA 21Z...AND KLNK 22Z. THE FROPA AT
KOFK WILL BE TOO SOON TO CONSIDER ANY PCPN ACTIVITY BUT SHOULD
SEE TSRA/IFR DEVELOPMENT AS BNDRY APPROACHES KOMA/KLNK. UNTIL
THEN EXPECT SLY WIND GUSTS 20-25KT. ALSO...CROSS WINDS THREAT WILL
INCREASE AT ALL TERMINALS LEADING UP TO FROPA THIS AFTN. VFR THEN
PREVAILING FROM THIS EVENING THRU THE REST OF THE FCST PD.
DEE
&&
.PREV DISCUSSION... /ISSUED 323 AM CDT SUN JUN 10 2012/
DISCUSSION...
THUNDERSTORM CHANCES TODAY...THEN COOLER TEMPERATURES INTO THE
MIDDLE OF THE WEEK...ARE THE PRIMARY FORECAST CONCERNS.
DEEP MID LEVEL LOW PRESSURE WAS NOTED FROM MONTANA INTO SOUTHERN
CANADA THIS MORNING...WITH STRONG SHORTWAVE ROTATING AROUND SOUTHERN
SIDE AS NOTED ON WATER VAPOR LOOPS. 110KT JET SEGMENT EXTENDING FROM
WYOMING THROUGH EASTERN MONTANA WAS AIDING COMPLEX OF STORMS NOW
MOVING THROUGH NORTHERN SOUTH DAKOTA. COLD FRONT ASSOCIATED WITH
THESE FEATURES EXTENDED FROM SOUTH DAKOTA CONVECTION INTO THE
NEBRASKA PANHANDLE. DESPITE WARM MID LEVEL TEMPERATURES CAPPING
SOUTHWARD DEVELOPMENT...LATEST HRRR MODEL RUNS SUGGEST SOME
SHOWERS WILL BUILD/DEVELOP SOUTH BEHIND FRONTAL BOUNDARY THIS
MORNING. AND IR SATELLITE PICTURES WERE SHOWING SOME MID LEVEL
CLOUD DEVELOPMENT IN THE PANHANDLE...LENDING CREDENCE TO HRRR
PRECIP FORECAST FARTHER SOUTH INTO NEBRASKA.
COLD FRONT WILL MOVE STEADILY SOUTHEAST...ENTERING OUR FAR NORTHWEST
CWA AROUND 15Z BASED ON GFS/HRRR FORECASTS. EXPECT PRECIPITATION TO
REMAIN BEHIND FRONTAL BOUNDARY FOR THE MOST PART THROUGH THE MORNING
HOURS AS CAPPING PROHIBITS WARM SECTOR DEVELOPMENT UNTIL LATER IN
THE AFTERNOON. COLD FRONT SHOULD APPROACH OMAHA TO LINCOLN LINE
AROUND 21Z WHEN RIBBON OF MID 60S DEW POINTS WILL LIE JUST AHEAD OF
BOUNDARY. TAKING INTO ACCOUNT MODELS OVER-FORECASTING DEW
POINTS...SUBJECTIVE SURFACE-BASED CAPES SHOULD BE NEAR 2000 J/KG
ALONG/AHEAD OF COLD FRONT WITH CAP ERODING AS TEMPERATURES REACH THE
85 TO 90 DEGREE RANGE. BULK SHEAR VALUES ARE ONLY MODEST IN OUR AREA
WHERE MID LEVEL WIND FIELDS WILL BE GENERALLY WEAK. BUT INSTABILITY
SHOULD BE SUFFICIENT FOR SOME POTENTIALLY SEVERE HAIL...AND DEW
POINT DEPRESSIONS MAY ALLOW FOR NEAR-SEVERE DOWNBURSTS.
FRONT SHOULD BE MOVING ACROSS THE MISSOURI RIVER BY LATE
AFTERNOON...THEN SWEEPING SOUTHEAST OF THE CWA OVERNIGHT. MOST
CONVECTION SHOULD BE SOUTH OF OUR AREA BY MIDNIGHT...WITH ONLY FAR
SOUTHEAST NEBRASKA AND SOUTHWEST IOWA SEEING RAIN CHANCES AFTER
MIDNIGHT. SIGNIFICANTLY COOLER AND DRIER AIR WILL BEGIN TO FILTER
INTO THE AREA LATE TONIGHT. HAVE LOWS IN THE MID TO UPPER 50S FOR
MOST OF THE AREA. THEN HIGH PRESSURE SETTLING INTO THE PLAINS ON
MONDAY WILL MAINTAIN NORTHWEST LOW LEVEL FLOW...USHERING IN EVEN
COOLER AND DRIER AIR. PLENTY OF SUNSHINE SHOULD PUSH HIGHS BACK
TOWARD 80 THEN...BUT LOWS IN THE LOWER 50S WILL BE COMMON MONDAY
NIGHT.
THE SURFACE HIGH WILL MOVE EAST ON TUESDAY ALLOWING SOUTHEAST WINDS
TO RETURN...AIDED BY DEVELOPING LOW PRESSURE IN THE HIGH PLAINS
AHEAD OF MID LEVEL SHORTWAVE. MODELS HAVE BEEN ADVERTISING
PRECIPITATION WITH THIS WAVE OVER THE LAST SEVERAL DAYS...AND THE
LATEST RUNS ARE NO DIFFERENT. EXPECT PRECIPITATION TO REMAIN WEST
OF OUR AREA DURING THE DAY TUESDAY...BUT SHOULD ROLL INTO
NORTHEAST NEBRASKA OVERNIGHT.
THE REST OF THE WEEK INTO SATURDAY IS BEGINNING TO LOOK MORE
UNSETTLED THAN PREVIOUS FORECASTS. DEVELOPING UPPER TROUGH ALONG THE
WEST COAST IS NOW ADVERTISED TO BE MORE OPEN THAN PREVIOUS MODEL
RUNS...ALLOWING FOR SOUTHWEST FLOW ALOFT TO RULE OVER THE MIDDLE OF
THE COUNTRY. THIS WILL ALLOW DISTURBANCES TO INITIATE RAIN CHANCES
FROM TIME TO TIME...ESPECIALLY FRIDAY INTO SATURDAY. GOING FORECAST
ALREADY HAD SMALL PRECIP CHANCES GOING...THUS WILL ONLY HAVE TO
TWEAK POPS UPWARD A TAD LATE IN THE WEEK.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
99/99
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
323 AM CDT SUN JUN 10 2012
.DISCUSSION...
THUNDERSTORM CHANCES TODAY...THEN COOLER TEMPERATURES INTO THE
MIDDLE OF THE WEEK...ARE THE PRIMARY FORECAST CONCERNS.
DEEP MID LEVEL LOW PRESSURE WAS NOTED FROM MONTANA INTO SOUTHERN
CANADA THIS MORNING...WITH STRONG SHORTWAVE ROTATING AROUND SOUTHERN
SIDE AS NOTED ON WATER VAPOR LOOPS. 110KT JET SEGMENT EXTENDING FROM
WYOMING THROUGH EASTERN MONTANA WAS AIDING COMPLEX OF STORMS NOW
MOVING THROUGH NORTHERN SOUTH DAKOTA. COLD FRONT ASSOCIATED WITH
THESE FEATURES EXTENDED FROM SOUTH DAKOTA CONVECTION INTO THE
NEBRASKA PANHANDLE. DESPITE WARM MID LEVEL TEMPERATURES CAPPING
SOUTHWARD DEVELOPMENT...LATEST HRRR MODEL RUNS SUGGEST SOME
SHOWERS WILL BUILD/DEVELOP SOUTH BEHIND FRONTAL BOUNDARY THIS
MORNING. AND IR SATELLITE PICTURES WERE SHOWING SOME MID LEVEL
CLOUD DEVELOPMENT IN THE PANHANDLE...LENDING CREDENCE TO HRRR
PRECIP FORECAST FARTHER SOUTH INTO NEBRASKA.
COLD FRONT WILL MOVE STEADILY SOUTHEAST...ENTERING OUR FAR NORTHWEST
CWA AROUND 15Z BASED ON GFS/HRRR FORECASTS. EXPECT PRECIPITATION TO
REMAIN BEHIND FRONTAL BOUNDARY FOR THE MOST PART THROUGH THE MORNING
HOURS AS CAPPING PROHIBITS WARM SECTOR DEVELOPMENT UNTIL LATER IN
THE AFTERNOON. COLD FRONT SHOULD APPROACH OMAHA TO LINCOLN LINE
AROUND 21Z WHEN RIBBON OF MID 60S DEW POINTS WILL LIE JUST AHEAD OF
BOUNDARY. TAKING INTO ACCOUNT MODELS OVER-FORECASTING DEW
POINTS...SUBJECTIVE SURFACE-BASED CAPES SHOULD BE NEAR 2000 J/KG
ALONG/AHEAD OF COLD FRONT WITH CAP ERODING AS TEMPERATURES REACH THE
85 TO 90 DEGREE RANGE. BULK SHEAR VALUES ARE ONLY MODEST IN OUR AREA
WHERE MID LEVEL WIND FIELDS WILL BE GENERALLY WEAK. BUT INSTABILITY
SHOULD BE SUFFICIENT FOR SOME POTENTIALLY SEVERE HAIL...AND DEW
POINT DEPRESSIONS MAY ALLOW FOR NEAR-SEVERE DOWNBURSTS.
FRONT SHOULD BE MOVING ACROSS THE MISSOURI RIVER BY LATE
AFTERNOON...THEN SWEEPING SOUTHEAST OF THE CWA OVERNIGHT. MOST
CONVECTION SHOULD BE SOUTH OF OUR AREA BY MIDNIGHT...WITH ONLY FAR
SOUTHEAST NEBRASKA AND SOUTHWEST IOWA SEEING RAIN CHANCES AFTER
MIDNIGHT. SIGNIFICANTLY COOLER AND DRIER AIR WILL BEGIN TO FILTER
INTO THE AREA LATE TONIGHT. HAVE LOWS IN THE MID TO UPPER 50S FOR
MOST OF THE AREA. THEN HIGH PRESSURE SETTLING INTO THE PLAINS ON
MONDAY WILL MAINTAIN NORTHWEST LOW LEVEL FLOW...USHERING IN EVEN
COOLER AND DRIER AIR. PLENTY OF SUNSHINE SHOULD PUSH HIGHS BACK
TOWARD 80 THEN...BUT LOWS IN THE LOWER 50S WILL BE COMMON MONDAY
NIGHT.
THE SURFACE HIGH WILL MOVE EAST ON TUESDAY ALLOWING SOUTHEAST WINDS
TO RETURN...AIDED BY DEVELOPING LOW PRESSURE IN THE HIGH PLAINS
AHEAD OF MID LEVEL SHORTWAVE. MODELS HAVE BEEN ADVERTISING
PRECIPITATION WITH THIS WAVE OVER THE LAST SEVERAL DAYS...AND THE
LATEST RUNS ARE NO DIFFERENT. EXPECT PRECIPITATION TO REMAIN WEST
OF OUR AREA DURING THE DAY TUESDAY...BUT SHOULD ROLL INTO
NORTHEAST NEBRASKA OVERNIGHT.
THE REST OF THE WEEK INTO SATURDAY IS BEGINNING TO LOOK MORE
UNSETTLED THAN PREVIOUS FORECASTS. DEVELOPING UPPER TROUGH ALONG THE
WEST COAST IS NOW ADVERTISED TO BE MORE OPEN THAN PREVIOUS MODEL
RUNS...ALLOWING FOR SOUTHWEST FLOW ALOFT TO RULE OVER THE MIDDLE OF
THE COUNTRY. THIS WILL ALLOW DISTURBANCES TO INITIATE RAIN CHANCES
FROM TIME TO TIME...ESPECIALLY FRIDAY INTO SATURDAY. GOING FORECAST
ALREADY HAD SMALL PRECIP CHANCES GOING...THUS WILL ONLY HAVE TO
TWEAK POPS UPWARD A TAD LATE IN THE WEEK.
DERGAN
&&
.AVIATION...
06Z TAFS FOR KOMA...KLNK...KOFK
PRIMARY CONCERN OVERNIGHT IS STILL POTENTIAL FOR LOW LEVEL WIND
SHEAR WITH SOUTHERLY LOW LEVEL JET. KEPT MENTION OF THIS AT ALL
THREE SITES UNTIL A LITTLE AFTER SUNRISE.
00Z NAM MODEL SEEMED TO HAVE A DECENT HANDLE ON SITUATION FOR
SUNDAY WITH INCREASING LOW LEVEL MOISTURE AND PRECIPITATION
CHANCES. FELT PROBABILITIES WERE HIGH ENOUGH TO MENTION TSRA IN
A PROB30 GROUP AT KOMA AND KLNK WITH CEILINGS BETWEEN 3000 AND
5000 FEET. CEILINGS COULD DROP TO AROUND 2500 FEET AFTER FRONTAL
PASSAGE AT ALL THREE SITES.
MILLER
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
149 AM EDT SUN JUN 10 2012
.SYNOPSIS...
A WARM FRONT WILL PUSH EASTWARD THROUGH LATE THIS AFTERNOON...TRIGGERING
SOME SCATTERED SHOWERS AND THUNDERSTORMS. THE FRONT WILL LIFT TO THE
NORTHEAST ON MONDAY WITH MAINLY WARM AND DRY WEATHER EXPECTED. THE
NEXT CHANCE FOR A SIGNIFICANT RAINFALL WILL COME TUESDAY AND TUESDAY
NIGHT AS A COLD FRONT MOVES INTO THE REGION FROM THE MIDWEST.
&&
.NEAR TERM /THROUGH TODAY/...
WATER VAPOR IMAGERY SHOWS DARKENING OVER SOUTHERN ONTARIO IN
ASSOCIATION WITH A SHORT WAVE ALOFT THAT WAS RIDING SOUTHEAST.
THIS WAVE WILL CROSS NY AND NE PA OVERNIGHT AND LEAD TO LIFTING
AND DESTABILIZATION ALOFT. THIS WILL ALLOW THE SHOWERS AND
THUNDERSTORMS THAT WERE OVER SOUTHERN ONTARIO TO SLIDE
SOUTHEASTWARD INTO CENTRAL NY AND THE EXTREME NE PART OF
PENNSYLVANIA BTWN 03Z AND 08Z OR SO. THE NAM AND RAP ALL SHOW
NEGATIVE SHOWALTER INDICES...WITH THE GFS SLIGHTLY NEGATIVE USING
A PARCEL FROM 800 MB. IN ANY EVENT...THERE WILL BE SOME ELEVATED
INSTABILITY WHICH WILL GENERATE SHOWERS AND ISOLATED
THUNDERSTORMS. SINCE THE ACTIVITY IS ELEVATED AND REALLY MARGINAL
WE DON/T EXPECT ANY SEVERE. I HAVE RAISED POPS FOR THE OVERNIGHT
MAINLY IN THE NORTHEAST 1/2 OF THE FORECAST AREA WHICH INCLUDES NC
AND EC NY AND EXTREME NE PA. KEPT MAINLY CHC POPS OR SLIGHTLY LESS
IN WC NY AND THE REST OF NE PA.
AFTER THIS WAVE PASSES BY THE WARM FRONT WILL RE-ORIENT ITSELF TO
EXTEND FROM ABT UCA SOUTHWARD TO THE POCONOS OR SO. MODEL SOUNDINGS
SHOW SOME INSTABILITY WITH INSOLATION ON SUNDAY TO THE TUNE OF
500-1000 J/KG. THE 0-6 KM SHEAR IS MARGINAL SUNDAY BUT WILL BE A
BIT HIGHER IN NE PA AND SC NY SO WILL HAVE HIGHER POPS FOR SCT
SHRA/TSRA MAINLT SRN PORTION OF CWA. PLUS THE FLOW WILL BE
NORTHWESTERLY WHICH WILL ALLOW AIR FROM LAKE ONTARIO TO STABILIZE
A LARGE PART OF THE FINGER LAKES REGION INTO THE HIGHLANDS OF
CNTRL NY. HENCE HAVE LOWER POPS IN THE ISLD CATEGORY FOR THESE
AREAS SUNDAY. SINCE CAPES AND SHEAR ARE NOT IMPRESSIVE NO SEVERE
IS EXPECTED.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY/...
MODELS SHOW THE OLD SFC BNDRY LINGERING OVER THE ERN ZONES INTO
MON DESPITE THE RDGG ALOFT. THIS WILL HELP ENHANCE THE CHANCE OF
CONV SHWRS AND ISLTD TRWS OVER THE HIER TERRAIN OF THE ERN ZONES.
OTRW...RDG LINE SLOWLY SLIDES EAST THRU THE PD ALLOWING A SFC TROF
AND SRN STREAM WV TO APRCH FOR TUE. MODELS CONT TO SHOW THE SYSTEM
TO BE WELL SUPPLIED WITH MOISTURE AS IT LFTS NWRD OUT OF THE GULF.
DVLPG UA JET BY TUES AHD OF THE SFC COLD FNT WILL HELP WRING OUT
THE MOISTURE OVER THE AREA ON TUE. LUCKILY...SYSTEM SEEMS QUITE
PROGRESSIVE...AT LEAST THRU THE SHRT TERM PD...WITH GFS FCSTD PWS
OF BETTER THAN 1.50 INCHES.
IT WILL BE QUITE WARM FOR THE PD...ESP SUN AND MON WITH TEMPS
PUSHING 90F IN THE LWR ELEVATIONS OF THE SRN AND WRN ZONES. ATTM
IT APPEARS WE WILL BE WELL BLO ANY HEAT FLAG THRESHOLDS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
PD BEGINS AS A COLD FNT IS PUSHING THRU THE FCST AREA. INITIAL
TIMING AMONG THE OPERATIONAL MODELS IS GOOD...THEN THE GFS DVLPS A
WV ALONG THE FNT OVER THE MID ATLANTIC...DELAYING THE EWRD
PROGRESS ON WED. THIS COULD CAUSE SOME SHWRS AND TRWS TO LINGER
OVER THE ERN ZONES INTO THU. ECMWF INDICATES SOME TROFINESS OVER
WRN NEW ENG AS WELL...SO BEST BET FCST IS TO CONT SOME CHANCE POPS
THRU MUCH OF THE FCST PD...WITH THE HIGHEST CHANCE OVER THE EAST
NEARER THE STALLED FNT OR SFC TROF. ALSO...BOTH MODELS SHOW ONLY
WEAK RDGG SFC AND ALOFT THRU THE PD...SO SOME CONV PSBL AT ALMOST
ANY TIME.
DFRNCS IN THE SFC PTRN DID MAKE SOME DFRNC IN THE FCSTD TEMPS FOR
THE PD. DECIDED TO START WITH HPC GUID FOR TEMPS...THEN BLENDED IN
SOME OF THE GFS BASED GUID TO BETTER ACCOUNT FOR THE UNCERTAINTY
AND TO BETTER COMPROMISE WITH SURROUNDING OFFICES.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
A WEAK UPPER LEVEL DISTURBANCE IS BRINGING SHOWERS TO THE AREA.
THERE HAS BEEN NO LIGHTENING ACTIVITY FOR OVER AN HOUR, AND EVEN
WHEN IT WAS SHOWING UP, THERE WERE VERY FEW STRIKES, SO TOOK MENTION OF
THUNDERSTORMS OUT OF THE TAFS. THE SHOWERS THAT ARE MOVING THROUGH
HAVE NOT BEEN LOWERING FLIGHT CATEGORIES THUS FAR. HOWEVER, THEY
ARE SUPPLYING SOME SFC MOISTURE, THAT, IF SKIES CLEAR, MAY PRODUCE
SOME FOG AND/OR LOW CIGS IN SOME LOCATIONS.
THINGS WILL CLEAR UP AFTER SUNRISE AS HIGH PRESSURE BUILDS ALOFT.
A WARM FRONT WILL BE MOVING THROUGH THE ARE TODAY, BUT MODELS ARE
SHOWING A FAIRLY STRONG CAP IN THE MID LEVELS THAT LOOKS TO INHIBIT
CONVECTIVE DEVELOPMENT TODAY. BUT, IF THE CAP TURNS OUT TO NOT BE
A STRONG AS CURRENTLY THOUGHT, TSRA COULD BE ADDED INTO THE TAFS
FOR THIS AFTERNOON. OTHERWISE, EXPECT VFR TODAY AND THIS EVENING.
WINDS ARE LIGHT AND VARIABLE THIS MORNING AND WILL REMAIN SO FOR
MOST OF THE DAY. A FEW LOCATIONS MAY PICK UP TO AROUND 5 KTS OUT
OF THE NW THIS AFTERNOON.
OUTLOOK...
SUN NGT/MON...MAINLY VFR...BUT VLY FOG PSBL EACH MRNG.
TUE...VFR GIVING WAY TO MVFR IN SCT TSRA
WED...VFR.
THU...VFR XCPT MVFR IN SCT TSRA.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN/SLI
NEAR TERM...DJN
SHORT TERM...DGM
LONG TERM...DGM
AVIATION...SLI
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
125 AM EDT SUN JUN 10 2012
.SYNOPSIS...
HIGH PRESSURE WILL GRADUALLY STRENGTHEN JUST OFF THE NEW ENGLAND
COAST. AS THIS HAPPENS, MUCH WARMER TEMPERATURES WILL MOVE INTO
THE REGION FROM THE SOUTHWEST, WITH HIGH TEMPERATURES INTO THE
80S. IT WILL ALSO BECOME MORE HUMID MONDAY AND TUESDAY. A COLD
FRONT WILL SLOWLY MOVE THROUGH THE REGION TUESDAY AND WEDNESDAY
ACCOMPANIED BY SHOWERS AND THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 110 AM EDT SUNDAY...FCST UPDATE UPCOMING TO FINE TUNE CLOUDS
AND TEMPS/DWPTS ACRS OUR CWA. CRNT IR SATL PIC SHOWS A BAND OF MID
LVL CLOUDS STREAMING ACRS NORTHERN NY INTO SOUTHERN VT...MAINLY
ALONG A KMSS TO KSLK TO KVSF LINE. THESE CLOUDS ALONG WITH A POOL
OF HIGHER SFC DWPTS WL KEEP TEMPS IN THE U50S SLV TO U40S DACKS TO
U30S/L40S NEK OF VT. ALSO...IF THE CLOUDS CAN BREAK UP...WHICH IS
SUGGESTED BY LATEST SATL TRENDS...PATCHY LOW CLOUDS/FOG WL DEVELOP
ACRS SLV AND DACKS. RUC 13 SHOWS SFC TO 900MB RH INCREASING BTWN
08-12Z...SO HAVE MENTIONED PATCHY FOG. OTHERWISE...REST OF FCST IN
GOOD SHAPE.
EARLIER DISCUSSION...
WITH THE STALLED BOUNDARY JUST OFF TO OUR SOUTHWEST, MUCH OF THE
FORECAST AREA HAS REMAINED ON THE DRIER SIDE OF THINGS. DEWPOINTS
HAVE FALLEN INTO THE 30S ACROSS NORTHEAST VERMONT WHILE HIGHER
HUMIDITY CONTINUES ACROSS NORTHERN NEW YORK WHERE DEWPOINTS ARE IN
THE 50S. VISIBLE SATELLITE IMAGERY DOES SHOW SOME CUMULUS
DEVELOPMENT OVER THE HIGHER TERRAIN OF THE ADIRONDACKS, SO PERHAPS
A SPRINKLE OR TWO FOR THE AFTERNOON.
FOR THE OVERNIGHT HOURS, IT WILL CONTINUE TO BE DRY. WITH
CLEAR/CALM CONDITIONS ACROSS THE NORTHEAST KINGDOM, EXCELLENT
RADIATIONAL COOLING WILL OCCUR AND IT`S EXPECTED THAT THE NORMALLY
COLD SPOTS IN THE PROTECTED HOLLOWS WILL BOTTOM OUT IN THE UPPER
30S (THOUGH NO FROST EXPECTED). PERHAPS A TOUCH OF FOG, BUT WITH
THE DRIER DEWPOINTS DON`T THINK THERE WILL BE MUCH THERE.
ACROSS NORTHERN NEW YORK, THE NEARNESS OF THE BOUNDARY AND PERHAPS
A LITTLE BIT OF CLOUDS WILL KEEP TEMPERATURES UP A BIT MORE. THE
HIGHER DEWPOINTS MAY ALSO LEAD TO A LITTLE MORE PATCHY FOG, SO I
ONLY KEPT MENTION IN THE FORECAST TO PARTS OF NORTHERN NEW YORK.
JUST AS A SIDE NOTE REGARDING TEMPERATURES -- EXPECT THE COLDEST
TEMPERATURES TO OCCUR IN THE LOW ELEVATIONS AND THE COOLER AIR
FLOWS DOWN THE MOUNTAINS. AS A RESULT, THE HIGHER ELEVATIONS OF
THE MOUNTAINS WILL END UP BEING SEVERAL DEGREES WARMER. FOR
EXAMPLE, I`M GOING 50F FOR MT MANSFIELD AND 48 HERE IN BURLINGTON.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/...
AS OF 330 PM EDT SATURDAY...THE PRIMARY WEATHER CHANGE FOR THIS
PERIOD WILL BE THE INCREASING WARMTH. HIGH PRESSURE WILL GET
ESTABLISHED AT THE SURFACE JUST TO OUR EAST, MEANWHILE RIDGING
WILL DEVELOP ALOFT. SOUTHWEST FLOW AT LOW/MID LEVELS WILL ADVECT
IN MUCH WARMER AIR. 850MB TEMPERATURES WILL REACH THE 11-14C LEVEL
SUNDAY AND THEN INCREASE FURTHER TO THE 14-16C RANGE MONDAY. WITH
A GOOD DEAL OF SUNSHINE EXPECTED, WE SHOULD SEE HIGHS TOP OUT INTO
THE LOWER 80S SUNDAY AND WELL INTO THE 80S ON MONDAY.
INITIALLY DEWPOINTS WILL STILL BE ON THE LOWER SIDE SUNDAY, BUT
CONTINUED SOUTHWEST FLOW WILL BRING UP THE DEWPOINTS BY MONDAY.
PROBABLY HIGH ENOUGH ON MONDAY TO START TO FEEL MORE HUMID.
DESPITE THE WARMTH AND THE DEVELOPMENT OF LOW LEVEL CAPE, THE OVERALL
ATMOSPHERE WILL BE RELATIVELY STABLE DUE TO SOME MID LEVEL
CAPPING, SO HAVE KEPT OUT ANY MENTION OF SHOWERS. JUST A NOTE FOR
THOSE LOOKING AT RAW OUTPUT OF THE NAM AND GFS -- BOTH THOSE
MODELS SEEM TO BE ADVECTING LOW LEVEL MOISTURE OFF OF LAKE
ONTARIO INTO THE ST LAWRENCE VALLEY RESULTING IN DEWPOINTS ON
MONDAY IN THE MID 70S! THIS IN TURN GIVES A CONSIDERABLE BULLSEYE
IN INSTABILITY FIELDS AND THE MODELS ARE EVEN TRYING TO DEVELOP
SOME CONVECTION. SUCH HIGH DEWPOINTS ARE NOT BELIEVABLE, SO HAVE
THUS IGNORED ANY OF THOSE "HINTS" WITHIN THE MODEL GUIDANCE.
WINDS WILL REMAIN FAIRLY LIGHT SUNDAY. IN FACT, ANTICIPATING LAKE
CHAMPLAIN BREEZE TO FULLY DEVELOP, SO LOOK FOR SOUTHEAST WINDS IN
PITTSBURGH AND WESTERLY WINDS IN BURLINGTON BY EARLY AFTERNOON.
A LITTLE MORE WIND ON MONDAY AS THE GRADIENT TIGHTENS A BIT.
PERHAPS SOME GUSTS ON THE ORDER OF 15 KNOTS. THE WIND WILL STAY UP
ON MONDAY NIGHT, ESPECIALLY IN THE CHAMPLAIN VALLEY. THIS WILL
MAKE FOR A VERY WARM (MOST EVERYONE STAYING IN THE 60S FOR LOWS) AND
PROBABLY NOT ALL THAT COMFORTABLE OF A SLEEPING NIGHT.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 348 PM EDT SATURDAY...SURFACE HIGH PRESSURE MOVES OFFSHORE
EARLY TUESDAY MORNING CLEARING THE WAY FOR A FRONTAL SYSTEM TO
MOVE THROUGH THE REGION TUESDAY EVENING THROUGH THURSDAY MORNING.
THIS SYSTEM WILL DEVELOP AN EXTENSIVE MOISTURE PLUME WITH
TELECONNECTING MOISTURE FROM THE GULF OF MEXICO AND WESTERN
ATLANTIC. WARM LAYER CLOUD DEPTHS INCREASE ALLOWING FOR MORE
EFFICIENT RAIN PROCESSES...THE QPF GRADIENT WILL BE ORIENTED WEST
TO EAST WITH HIGHEST TOTALS FOR TUESDAY APPROACHING 0.25 INCHES IN
THE SOUTHWESTERN SAINT LAWRENCE VALLEY AND EXTEND TO THE GREEN
MOUNTAINS. THE BULK OF THE ENERGY SUPPORTING FOR THIS SYSTEM
RAPIDLY PULLS NORTHWARD AND THE FRONT SLOWLY DROPS SOUTHEASTWARD
WEDNESDAY INTO THURSDAY. WINDS REMAIN SOUTHERLY KEEPING
TEMPERATURES NEAR NORMAL VALUES WITH HIGHS MAINLY IN THE 75 TO 80
DEGREE RANGE AND LOWS IN THE UPPER 50 TO LOW 60S...SAINT LAWRENCE
VALLEY MAY NOT WARM AS MUCH AS THE REST OF THE FORECAST REGION
TUESDAY DUE TO THE EARLIER ONSET OF CLOUD COVER AND PRECIPITATION
REMAINING IN THE MID 70S. THE UPPER RIDGE BUILDS OVER THE AREA
TOWARDS THE END OF THE WEEK SHUTTING OFF PRECIPITATION
CHANCES...GFS SHOWS UPPER FLOW MAINLY NORTHWESTERLY WITH CHANCES
OF PRECIP CONTINUING OVER HIGHER TERRAIN WHILE THE ECMWF HAS THE
UPPER RIDGE BUILDING INTO CANADA SHUNTING MOISTURE WELL AWAY FROM
THE REGION. HAVE MAINTAINED SOME SLIGHT CHANCES OVER THE TERRAIN
TOWARDS THE END OF THE WEEK.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
THROUGH 06Z MONDAY...AVIATION FOCUS WL BE POTENTIAL IFR AT SLK/MSS
THIS MORNING. IR SATL TRENDS SHOW MID LVL CLOUDS BREAKING UP ACRS
NORTHERN NY THIS MORNING WITH SOME BR DEVELOPING AT SLK/OGS. RUC13
AND NAM12 SHOW MID LVL CLOUDS DECREASING IN AREAL COVERAGE ACRS
THIS REGION...ALONG WITH PLENTY OF BL MOISTURE DEVELOPING AS SFC
DWPTS HOLD IN THE U50S TO L60S. THIS RH...COMBINED WITH LIGHT SFC
WINDS WL HELP TO PRODUCE PERIODS OF MVFR/IFR AT SLK/MSS BTWN 08Z-
11Z THIS MORNING. ELSEWHERE...SOUNDINGS SHOW A DEEP DRY LAYER WITH
TEMPS NOT REACHING THE CROSS POINT...THEREFORE NOT EXPECTING
FOG/BR TO DEVELOP AT MPV/PBG/RUT/BTV. WINDS WL BE LIGHT AND
VARIABLE...EXCEPT 140@05KT AT RUT THRU 13Z THIS MORNING. VFR
CONDITIONS WITH SFC HIGH PRES AND BUILDING RIDGE ALOFT WL PREVAIL
TODAY...WITH LIGHT NORTH WINDS.
OUTLOOK 06Z MONDAY THROUGH THURSDAY...
06Z MONDAY THROUGH 12Z TUESDAY...BUILDING MID/UPPER LVL RIDGE AND
ASSOCAITED SFC HIGH PRES WL RESULT IN VFR CONDITIONS THRU TUES
AFTN. NEXT SYSTEM IMPACTS FA LATE TUES INTO WEDS WITH SCATTERED
SHOWERS/STORMS ALONG WITH BRIEF PERIODS OF MVFR CONDITIONS. SOME
FOG/BR WITH IFR CONDITIONS POSSIBLE AT SLK/MPV WEDS MORNING AND
AGAIN ON THURS.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...NASH
NEAR TERM...TABER
SHORT TERM...NASH
LONG TERM...BOYD
AVIATION...TABER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
103 AM EDT SUN JUN 10 2012
.SYNOPSIS...
HIGH PRESSURE WILL GRADUALLY STRENGTHEN JUST OFF THE NEW ENGLAND
COAST. AS THIS HAPPENS, MUCH WARMER TEMPERATURES WILL MOVE INTO
THE REGION FROM THE SOUTHWEST, WITH HIGH TEMPERATURES INTO THE
80S. IT WILL ALSO BECOME MORE HUMID MONDAY AND TUESDAY. A COLD
FRONT WILL SLOWLY MOVE THROUGH THE REGION TUESDAY AND WEDNESDAY
ACCOMPANIED BY SHOWERS AND THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 110 AM EDT SUNDAY...FCST UPDATE UPCOMING TO FINE TUNE CLOUDS
AND TEMPS/DWPTS ACRS OUR CWA. CRNT IR SATL PIC SHOWS A BAND OF MID
LVL CLOUDS STREAMING ACRS NORTHERN NY INTO SOUTHERN VT...MAINLY
ALONG A KMSS TO KSLK TO KVSF LINE. THESE CLOUDS ALONG WITH A POOL
OF HIGHER SFC DWPTS WL KEEP TEMPS IN THE U50S SLV TO U40S DACKS TO
U30S/L40S NEK OF VT. ALSO...IF THE CLOUDS CAN BREAK UP...WHICH IS
SUGGESTED BY LATEST SATL TRENDS...PATCHY LOW CLOUDS/FOG WL DEVELOP
ACRS SLV AND DACKS. RUC 13 SHOWS SFC TO 900MB RH INCREASING BTWN
08-12Z...SO HAVE MENTIONED PATCHY FOG. OTHERWISE...REST OF FCST IN
GOOD SHAPE.
EARLIER DISCUSSION...
WITH THE STALLED BOUNDARY JUST OFF TO OUR SOUTHWEST, MUCH OF THE
FORECAST AREA HAS REMAINED ON THE DRIER SIDE OF THINGS. DEWPOINTS
HAVE FALLEN INTO THE 30S ACROSS NORTHEAST VERMONT WHILE HIGHER
HUMIDITY CONTINUES ACROSS NORTHERN NEW YORK WHERE DEWPOINTS ARE IN
THE 50S. VISIBLE SATELLITE IMAGERY DOES SHOW SOME CUMULUS
DEVELOPMENT OVER THE HIGHER TERRAIN OF THE ADIRONDACKS, SO PERHAPS
A SPRINKLE OR TWO FOR THE AFTERNOON.
FOR THE OVERNIGHT HOURS, IT WILL CONTINUE TO BE DRY. WITH
CLEAR/CALM CONDITIONS ACROSS THE NORTHEAST KINGDOM, EXCELLENT
RADIATIONAL COOLING WILL OCCUR AND IT`S EXPECTED THAT THE NORMALLY
COLD SPOTS IN THE PROTECTED HOLLOWS WILL BOTTOM OUT IN THE UPPER
30S (THOUGH NO FROST EXPECTED). PERHAPS A TOUCH OF FOG, BUT WITH
THE DRIER DEWPOINTS DON`T THINK THERE WILL BE MUCH THERE.
ACROSS NORTHERN NEW YORK, THE NEARNESS OF THE BOUNDARY AND PERHAPS
A LITTLE BIT OF CLOUDS WILL KEEP TEMPERATURES UP A BIT MORE. THE
HIGHER DEWPOINTS MAY ALSO LEAD TO A LITTLE MORE PATCHY FOG, SO I
ONLY KEPT MENTION IN THE FORECAST TO PARTS OF NORTHERN NEW YORK.
JUST AS A SIDE NOTE REGARDING TEMPERATURES -- EXPECT THE COLDEST
TEMPERATURES TO OCCUR IN THE LOW ELEVATIONS AND THE COOLER AIR
FLOWS DOWN THE MOUNTAINS. AS A RESULT, THE HIGHER ELEVATIONS OF
THE MOUNTAINS WILL END UP BEING SEVERAL DEGREES WARMER. FOR
EXAMPLE, I`M GOING 50F FOR MT MANSFIELD AND 48 HERE IN BURLINGTON.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/...
AS OF 330 PM EDT SATURDAY...THE PRIMARY WEATHER CHANGE FOR THIS
PERIOD WILL BE THE INCREASING WARMTH. HIGH PRESSURE WILL GET
ESTABLISHED AT THE SURFACE JUST TO OUR EAST, MEANWHILE RIDGING
WILL DEVELOP ALOFT. SOUTHWEST FLOW AT LOW/MID LEVELS WILL ADVECT
IN MUCH WARMER AIR. 850MB TEMPERATURES WILL REACH THE 11-14C LEVEL
SUNDAY AND THEN INCREASE FURTHER TO THE 14-16C RANGE MONDAY. WITH
A GOOD DEAL OF SUNSHINE EXPECTED, WE SHOULD SEE HIGHS TOP OUT INTO
THE LOWER 80S SUNDAY AND WELL INTO THE 80S ON MONDAY.
INITIALLY DEWPOINTS WILL STILL BE ON THE LOWER SIDE SUNDAY, BUT
CONTINUED SOUTHWEST FLOW WILL BRING UP THE DEWPOINTS BY MONDAY.
PROBABLY HIGH ENOUGH ON MONDAY TO START TO FEEL MORE HUMID.
DESPITE THE WARMTH AND THE DEVELOPMENT OF LOW LEVEL CAPE, THE OVERALL
ATMOSPHERE WILL BE RELATIVELY STABLE DUE TO SOME MID LEVEL
CAPPING, SO HAVE KEPT OUT ANY MENTION OF SHOWERS. JUST A NOTE FOR
THOSE LOOKING AT RAW OUTPUT OF THE NAM AND GFS -- BOTH THOSE
MODELS SEEM TO BE ADVECTING LOW LEVEL MOISTURE OFF OF LAKE
ONTARIO INTO THE ST LAWRENCE VALLEY RESULTING IN DEWPOINTS ON
MONDAY IN THE MID 70S! THIS IN TURN GIVES A CONSIDERABLE BULLSEYE
IN INSTABILITY FIELDS AND THE MODELS ARE EVEN TRYING TO DEVELOP
SOME CONVECTION. SUCH HIGH DEWPOINTS ARE NOT BELIEVABLE, SO HAVE
THUS IGNORED ANY OF THOSE "HINTS" WITHIN THE MODEL GUIDANCE.
WINDS WILL REMAIN FAIRLY LIGHT SUNDAY. IN FACT, ANTICIPATING LAKE
CHAMPLAIN BREEZE TO FULLY DEVELOP, SO LOOK FOR SOUTHEAST WINDS IN
PITTSBURGH AND WESTERLY WINDS IN BURLINGTON BY EARLY AFTERNOON.
A LITTLE MORE WIND ON MONDAY AS THE GRADIENT TIGHTENS A BIT.
PERHAPS SOME GUSTS ON THE ORDER OF 15 KNOTS. THE WIND WILL STAY UP
ON MONDAY NIGHT, ESPECIALLY IN THE CHAMPLAIN VALLEY. THIS WILL
MAKE FOR A VERY WARM (MOST EVERYONE STAYING IN THE 60S FOR LOWS) AND
PROBABLY NOT ALL THAT COMFORTABLE OF A SLEEPING NIGHT.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 348 PM EDT SATURDAY...SURFACE HIGH PRESSURE MOVES OFFSHORE
EARLY TUESDAY MORNING CLEARING THE WAY FOR A FRONTAL SYSTEM TO
MOVE THROUGH THE REGION TUESDAY EVENING THROUGH THURSDAY MORNING.
THIS SYSTEM WILL DEVELOP AN EXTENSIVE MOISTURE PLUME WITH
TELECONNECTING MOISTURE FROM THE GULF OF MEXICO AND WESTERN
ATLANTIC. WARM LAYER CLOUD DEPTHS INCREASE ALLOWING FOR MORE
EFFICIENT RAIN PROCESSES...THE QPF GRADIENT WILL BE ORIENTED WEST
TO EAST WITH HIGHEST TOTALS FOR TUESDAY APPROACHING 0.25 INCHES IN
THE SOUTHWESTERN SAINT LAWRENCE VALLEY AND EXTEND TO THE GREEN
MOUNTAINS. THE BULK OF THE ENERGY SUPPORTING FOR THIS SYSTEM
RAPIDLY PULLS NORTHWARD AND THE FRONT SLOWLY DROPS SOUTHEASTWARD
WEDNESDAY INTO THURSDAY. WINDS REMAIN SOUTHERLY KEEPING
TEMPERATURES NEAR NORMAL VALUES WITH HIGHS MAINLY IN THE 75 TO 80
DEGREE RANGE AND LOWS IN THE UPPER 50 TO LOW 60S...SAINT LAWRENCE
VALLEY MAY NOT WARM AS MUCH AS THE REST OF THE FORECAST REGION
TUESDAY DUE TO THE EARLIER ONSET OF CLOUD COVER AND PRECIPITATION
REMAINING IN THE MID 70S. THE UPPER RIDGE BUILDS OVER THE AREA
TOWARDS THE END OF THE WEEK SHUTTING OFF PRECIPITATION
CHANCES...GFS SHOWS UPPER FLOW MAINLY NORTHWESTERLY WITH CHANCES
OF PRECIP CONTINUING OVER HIGHER TERRAIN WHILE THE ECMWF HAS THE
UPPER RIDGE BUILDING INTO CANADA SHUNTING MOISTURE WELL AWAY FROM
THE REGION. HAVE MAINTAINED SOME SLIGHT CHANCES OVER THE TERRAIN
TOWARDS THE END OF THE WEEK.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
THROUGH 00Z MONDAY...MAINLY VFR CONDITIONS EXPECTED THROUGH THE
PERIOD. UPPER LEVEL RIDGE OF TO OUR WEST WILL CONTINUE TO STREAM
SCT-BKN MID CLOUDS ACROSS NORTHERN NEW YORK AND SOUTHERN VERMONT
TONIGHT. ELSEWHERE...EXPECT ONLY FEW-SCT MID CLOUDS WHICH MAY
ALLOW FOR SOME FOG DEVELOPMENT AT KMPV LATE TONIGHT. AFTER 15Z
SUNDAY...EXPECT MID CLOUDS TO MOVE OFF WITH ONLY FEW-SCT DIURNAL
MOUNTAIN CUMULUS FORMING.
OUTLOOK 00Z MONDAY THROUGH THURSDAY...
00Z MONDAY THROUGH 12Z TUESDAY...VFR UNDER HIGH PRESSURE. EARLY
MORNING PATCHY FOG/BR POSSIBLE AT KMPV/KSLK.
12Z TUESDAY THROUGH 00Z THURSDAY...VFR TRENDING TO MVFR IN SHOWERS
AND THUNDERSTORMS AS A COLD FRONT SLOWLY TRUDGES ACROSS THE REGION.
00Z THURSDAY THROUGH 00Z FRIDAY. VFR UNDER HIGH PRESSURE. EARLY
MORNING PATCHY FOG/BR POSSIBLE AT KMPV/KSLK.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...NASH
NEAR TERM...TABER
SHORT TERM...NASH
LONG TERM...BOYD
AVIATION...LAHIFF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
315 AM EDT SUN JUN 10 2012
.SYNOPSIS...
RIDGING AT THE SURFACE AND ALOFT WILL EXTEND ALONG THE SOUTHEAST
COAST THROUGH TONIGHT. MEANWHILE...VERY MOIST AIR ATTENDANT TO A
SOUTHERN STREAM WAVE ALOFT WILL OVERSPREAD THE CAROLINAS FROM THE
SOUTH LATE TONIGHT INTO MONDAY...AND LINGER THROUGH MIDWEEK.
&&
.NEAR TERM /THROUGH MONDAY NIGHT/...
AS OF 930 PM SATURDAY...
TONIGHT:
WEAK SOUTHERLY RETURN FLOW HAS DEVELOPED ACROSS THE AREA THIS
EVENING IN RESPONSE TO EASTWARD SHIFT OF A 1019MB SURFACE
OFF THE SOUTHEAST COAST. DEWPOINTS HAVE ALREADY RESPONDED...
RUNNING ANYWHERE FROM 5 TO 10 DEGREE FAHRENHEIT WARMER THAN THIS
SAME TIME LAST NIGHT.
CENTRAL NC WILL CONTINUE TO SEE HIGH LEVEL MOISTURE/CLOUDS SPREAD
INTO THE AREA DOWNSTREAM FROM THE SOUTHERN STREAM WAVE OVER THE NW
GULF OF MEXICO. RUC ANALYSIS SHOWS A FAIRLY WELL-DEFINED VORTICITY
SHEAR AXIS EMANATING NORTHEASTWARD AWAY FROM THE BROAD MID-LEVEL
CIRCULATION AND MOVING TOWARDS THE CAROLINAS THROUGH DAYBREAK.
AS SUCH...EXPECT TO SEE A FAIR AMOUNT OF HIGH CLOUDS OVERNIGHT...
PRODUCING GENERALLY MOSTLY CLOUDY SKIES. THESE CLOUDS AND THE
MODERATING AIR MASS WILL RESULT IN A MUCH MILDER NIGHT WITH MORNING
LOWS PREDOMINATELY IN THE MID 60S. -CBL
SUNDAY...WITH THE MID LEVEL RIDGE FORECAST TO HOLD OVER THE
REGION...THE BEST MOISTURE IS EXPECTED TO STREAM NORTHWARD AND
REMAIN WEST OF THE MOUNTAINS...KEEPING CENTRAL NC MOSTLY DRY.
HOWEVER...THE GFS AND ECMWF HAVE BEEN MORE AGGRESSIVE WITH
BRINGING IN MOISTURE EAST OF THE MOUNTAINS AS THEY WEAKEN THE
RIDGE A LITTLE MORE OVER WESTERN NC. AS A RESULT...THEY SHOW MORE
IN THE WAY OF PRECIP CHANCES MOVING INTO THE EXTREME SOUTHWESTERN
PORTIONS OF THE FORECAST AREA BY LATE SUNDAY AFTERNOON. WILL
MAINTAIN THE SLIGHT CHANCE POP ACROSS THE EXTREME SOUTHWESTERN CWA
FOR LATE SUNDAY AFTERNOON. CLOUDS WILL INCREASE FROM SOUTHWEST TO
NORTHEAST THROUGHOUT THE DAY WITH THE APPROACH OF THE MID LEVEL
WAVE. AS A RESULT...TEMPS WILL LIKELY BE NOT AS WARM ACROSS THE
SOUTHWEST (WHERE THERE WILL BE MORE CLOUDS FOR A LONGER PART OF
THE DAY) AND AM GENERALLY EXPECTING HIGHS TO RANGE FROM THE NEAR
90 DEGREES ACROSS THE NORTHEAST TO MID/UPPER 80S ACROSS THE
SOUTHWEST.
SUNDAY NIGHT...850MB WARM FRONT EXPECTED TO BE DRAPED ACROSS
SC...ITS NWD PROGRESS IMPEDED BY A MID LEVEL RIDGE EXTENDING NW-SE
ACROSS CENTRAL NC. THIS RIDGE EVENTUALLY WEAKENS...ALLOWING THE
850MB WARM FRONT TO EDGE NWD INTO OUR REGION BY EARLY MONDAY.
DEVELOPING S-SW FLOW ALOFT WILL BEGIN TO USHER VERY MOIST AIR INTO
CENTRAL NC. PRECIP WATER VALUES PROJECTED TO INCREASE BY 100 PERCENT
FROM SUNDAY MORNING TO MONDAY MORNING WITH PW VALUES BY EARLY MONDAY
1.5-1.8 INCHES. WEAK ISENTROPIC LIFT NOTED AHEAD OF THE 850MB WARM
FRONT...MAINLY OVER THE SW THIRD OF THE FORECAST AREA SUNDAY
EVENING. WHILE MODEL GUIDANCE HAS BEEN FAIRLY CONSISTENT IN
DEPICTING A THREAT FOR ISOLATED/SCATTERED CONVECTION OVER OUR W-SW
COUNTIES BY SUNDAY EVENING...PRESENCE OF MID LEVEL RIDGE OVER OUR
REGION MAY HOLD OFF RAIN THREAT UNTIL LATE SUNDAY NIGHT (4-6 HOURS
LATER THAN MODEL PROJECTIONS). STILL...DO NOT PLAN TO CHANGE LITTLE
FROM PREVIOUS FORECAST AS THERE APPEARS TO BE ENOUGH PARAMETERS IN
PLACE TO WARRANT A SLIGHT-SMALL CHANCE POP FOR SUNDAY NIGHT OVER
ROUGHLY THE SW HALF OF THE CWA. IT WILL BE NOTICEABLY MORE HUMID
ACROSS THE REGION SUNDAY NIGHT WHICH...ALONG WITH
INCREASING/THICKENING CLOUD COVERAGE...WILL LEAD TO OVERNIGHT MINS
3-5 DEGREES WARMER THAN PREVIOUS NIGHTS. MIN TEMPS MID-UPPER 60S.
MONDAY-MONDAY NIGHT...UPPER LEVEL TROUGH OVER THE LOWER MS VALLEY
LATE SUNDAY LIFTS NEWD...NUDGED ALONG BY A DEEPER TROUGH CROSSING
THE NORTHERN PLAINS. BY MON AM...THE SOUTHERN TROUGH WILL BE IN THE
TN VALLEY AND CONTINUE TO INCH SLOWLY ENE. THIS FEATURE WILL CAUSE
AN OPEN FEED OF MOISTURE FROM THE GULF INTO THE CAROLINA.
PERTURBATIONS IN THE SW FLOW AHEAD OF THE TROUGH INTERACTING WITH
THE MOIST AND UNSTABLE AIR MASS WILL TRIGGER ROUNDS OF SHOWERS AND
T-STORMS. EXPECT COVERAGE TO BE GREATEST IN THE WEST VERSUS EAST AS
DEEPER MOISTURE AND BETTER ORGANIZED LIFT WILL RESIDE IN THE WESTERN
PIEDMONT COMPARED TO THE COASTAL PLAIN. HOWEVER THE AIR MASS MAY BE
MORE UNSTABLE IN THE EAST SINCE THIS REGION MAY SEE SOME PARTIAL
SUN. THIS WILL LEAD TO THE POTENTIAL FOR STRONG STORMS IN THE EAST
MONDAY AFTERNOON-MONDAY NIGHT. DUE TO CONVECTION AND CLOUD
COVERAGE...EXPECT AFTERNOON TEMPS TO AVERAGE A FEW DEGREES SHY OF
NORMAL. MAX TEMPS LOW-MID 80S. MIN TEMPS MONDAY NIGHT UPPER 60S TO
NEAR 70.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 AM...
A MID LEVEL TROUGH WILL BE PUSHING EAST OFF THE MOUNTAINS TUESDAY
MORNING WITH CONVERGENT... THOUGH WEAK NEAR SURFACE FLOW AHEAD OF
IT. PRECIPITABLE WATERS WELL ABOVE NORMAL AT AROUND TWO INCHES WITH
POTENTIAL ENERGY RISING ABOVE 2500 JOULES/KILOGRAM. SOME SHOWERS OR
A THUNDERSTORM POSSIBLE ALMOST ANY TIME TUESDAY... BUT CHANCES ARE
CERTAINLY HIGHEST WITH THE HEAT OF THE DAY AND NEAR AND EAST OF THE
MID LEVEL TROUGH (HIGHWAY ONE AND EAST). GIVEN SOMEWHAT SLOW CELL
MOVEMENT A FLOODING THREAT WILL EXIST. AFTERNOON INSTABILITY WILL
PRESENT THE THREAT FOR PRECIPITATION LOADING OF DOWNDRAFTS AND
POSSIBLE DAMAGING WINDS.
THE SURFACE AND MID LEVEL TROUGHS REACH THE COASTAL PLAIN BY SUNRISE
WEDNESDAY... AND WINDS SHIFT TOWARD NORTHEAST DURING THE DAY. THE
AIR COLUMN IN THE WEST DRYS OUT WITH MINIMAL DRYING EAST. POTENTIAL
ENERGY FOR THE AFTERNOON IS FORECAST ABOVE 2500 ACROSS THE AREA.
CONVECTION IN THE WEST COULD BE WIDELY SCATTERED TO ABSENT IF DRYING
ALOFT IS SIGNIFICANT. MORE COVERAGE IN THE EAST BUT POPS NO HIGHER
THAN 50 PERCENT. LOW LEVEL TRIGGERS OTHER THAN HEATING SEEM ABSENT
THOUGH MODELS IN ROUGH AGREEMENT IN A POTENTIAL SHORT WAVE CROSSING
THE AREA DURING THE AFTERNOON. A THREAT FOR DAMAGING WINDS WITH THE
STRONGER THUNDERSTORMS WILL EXIST... BUT THE LIKELIHOOD IS REDUCED
FROM TUESDAY... ESPECIALLY WEST.
WITH LOSS OF HEATING... MOST CONVECTION SHOULD END IN THE EVENING
AND MUCH OF THE NIGHT EXPECTED TO BE DRY.
AFTERNOON HIGH TEMPERATURES WILL BE TRICKY WITH CLOUDS AND
PRECIPITATION TUESDAY. LESS COVERAGE WEDNESDAY BUT NORTHEAST FLOW
WILL TEMPER EXPECTED HIGHS FROM LOW LEVEL THICKNESSES. HIGH
TEMPERATURES MOSTLY MID 80S. LOW TEMPERATURES 65 TO 70 UNDER MUGGY
CONDITIONS.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 315 AM...
THE ECMWF SOLUTION FROM THE SATURDAY MORNING MODEL RUN IS NOW THE
CONSENSUS WITH SURFACE FLOW GENERALLY NORTHEAST THROUGH THE PERIOD.
THE BEST RAIN CHANCE DURING THIS PERIOD NO MORE THAN SLIGHT AND
HIGHEST FRIDAY WITH WEAK SURFACE FLOW SHIFTING MORE TOWARD EAST.
HIGH PRESSURE OVER SOUTHEAST CANADA THURSDAY WILL NOSE DOWN INTO THE
CAROLINAS THURSDAY EVENING AND NIGHT THEN REMAIN STATIC INTO
SATURDAY. OVERNIGHT LOW TEMPERATURES MOSTLY MID 60S WITH HIGH
TEMPERATURES IN THE MID 80S.
&&
.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
AS OF 215 AM SUNDAY...
CONTINUED RIDGING AT THE SURFACE AND ALOFT WILL MAINTAIN DRY VFR
CONDITIONS THROUGH MOST OF THE 24-HOUR TAF PERIOD. HOWEVER...THE
APPROACH OF A SOUTHERN STREAM WAVE ALOFT AND ASSOCIATED LOW LEVEL
FRONTAL ZONE MAY SPARK A FEW WIDELY SCATTERED SHOWERS IN THE
VICINITY OF KINT/KGSO/KFAY LATE THIS AFTERNOON OR THIS EVENING...BUT
THE BULK OF THIS ACTIVITY WILL LIKELY HOLD NEAR KCLT AND POINTS
SOUTHWESTWARD UNTIL AFTER THE 06Z TAF PERIOD. THE APPROACH OF THE
AFOREMENTIONED LOW LEVEL FRONTAL ZONE WILL ALSO CAUSE MVFR RANGE
STRATUS TO SPREAD NORTHWARD AND AFFECT KINT AND POSSIBLY KGSO BY
AROUND 06Z. GENERALLY LIGHT SOUTH SOUTHWEST SURFACE WINDS WILL
PREVAIL THROUGH THE PERIOD...RELATIVELY STRONGEST BETWEEN 7-11 KTS
THIS AFTERNOON.
LOOKING AHEAD: THE MVFR RANGE STRATUS WILL ADVANCE NORTHEASTWARD AND
AFFECT THE REMAINDER OF CENTRAL NC TERMINALS LATE TONIGHT INTO
MONDAY...COINCIDENT WITH AN INCREASING CHANCE OF SHOWERS AND
ISOLATED THUNDERSTORMS DURING THAT TIME. PERIODS OF MVFR CEILINGS...
AND SHOWERS AND STORMS...WILL THEN LIKELY PERSIST THROUGH
WEDNESDAY...BEFORE A RETURN TO DRIER VFR CONDITIONS BEHIND A COLD
FRONT BY WEDNESDAY NIGHT.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MWS
NEAR TERM...CBL/KRR
SHORT TERM...
LONG TERM...WSS
AVIATION...MWS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
301 AM EDT SUN JUN 10 2012
.SYNOPSIS...
RIDGING AT THE SURFACE AND ALOFT WILL EXTEND ALONG THE SOUTHEAST
COAST THROUGH TONIGHT. MEANWHILE...VERY MOIST AIR ATTENDANT TO A
SOUTHERN STREAM WAVE ALOFT WILL OVERSPREAD THE CAROLINAS FROM THE
SOUTH LATE TONIGHT INTO MONDAY...AND LINGER THROUGH MIDWEEK.
&&
.NEAR TERM /THROUGH MONDAY NIGHT/...
AS OF 930 PM SATURDAY...
TONIGHT:
WEAK SOUTHERLY RETURN FLOW HAS DEVELOPED ACROSS THE AREA THIS
EVENING IN RESPONSE TO EASTWARD SHIFT OF A 1019MB SURFACE
OFF THE SOUTHEAST COAST. DEWPOINTS HAVE ALREADY RESPONDED...
RUNNING ANYWHERE FROM 5 TO 10 DEGREE FAHRENHEIT WARMER THAN THIS
SAME TIME LAST NIGHT.
CENTRAL NC WILL CONTINUE TO SEE HIGH LEVEL MOISTURE/CLOUDS SPREAD
INTO THE AREA DOWNSTREAM FROM THE SOUTHERN STREAM WAVE OVER THE NW
GULF OF MEXICO. RUC ANALYSIS SHOWS A FAIRLY WELL-DEFINED VORTICITY
SHEAR AXIS EMANATING NORTHEASTWARD AWAY FROM THE BROAD MID-LEVEL
CIRCULATION AND MOVING TOWARDS THE CAROLINAS THROUGH DAYBREAK.
AS SUCH...EXPECT TO SEE A FAIR AMOUNT OF HIGH CLOUDS OVERNIGHT...
PRODUCING GENERALLY MOSTLY CLOUDY SKIES. THESE CLOUDS AND THE
MODERATING AIR MASS WILL RESULT IN A MUCH MILDER NIGHT WITH MORNING
LOWS PREDOMINATELY IN THE MID 60S. -CBL
SUNDAY...WITH THE MID LEVEL RIDGE FORECAST TO HOLD OVER THE
REGION...THE BEST MOISTURE IS EXPECTED TO STREAM NORTHWARD AND
REMAIN WEST OF THE MOUNTAINS...KEEPING CENTRAL NC MOSTLY DRY.
HOWEVER...THE GFS AND ECMWF HAVE BEEN MORE AGGRESSIVE WITH
BRINGING IN MOISTURE EAST OF THE MOUNTAINS AS THEY WEAKEN THE
RIDGE A LITTLE MORE OVER WESTERN NC. AS A RESULT...THEY SHOW MORE
IN THE WAY OF PRECIP CHANCES MOVING INTO THE EXTREME SOUTHWESTERN
PORTIONS OF THE FORECAST AREA BY LATE SUNDAY AFTERNOON. WILL
MAINTAIN THE SLIGHT CHANCE POP ACROSS THE EXTREME SOUTHWESTERN CWA
FOR LATE SUNDAY AFTERNOON. CLOUDS WILL INCREASE FROM SOUTHWEST TO
NORTHEAST THROUGHOUT THE DAY WITH THE APPROACH OF THE MID LEVEL
WAVE. AS A RESULT...TEMPS WILL LIKELY BE NOT AS WARM ACROSS THE
SOUTHWEST (WHERE THERE WILL BE MORE CLOUDS FOR A LONGER PART OF
THE DAY) AND AM GENERALLY EXPECTING HIGHS TO RANGE FROM THE NEAR
90 DEGREES ACROSS THE NORTHEAST TO MID/UPPER 80S ACROSS THE
SOUTHWEST.
SUNDAY NIGHT...850MB WARM FRONT EXPECTED TO BE DRAPED ACROSS
SC...ITS NWD PROGRESS IMPEDED BY A MID LEVEL RIDGE EXTENDING NW-SE
ACROSS CENTRAL NC. THIS RIDGE EVENTUALLY WEAKENS...ALLOWING THE
850MB WARM FRONT TO EDGE NWD INTO OUR REGION BY EARLY MONDAY.
DEVELOPING S-SW FLOW ALOFT WILL BEGIN TO USHER VERY MOIST AIR INTO
CENTRAL NC. PRECIP WATER VALUES PROJECTED TO INCREASE BY 100 PERCENT
FROM SUNDAY MORNING TO MONDAY MORNING WITH PW VALUES BY EARLY MONDAY
1.5-1.8 INCHES. WEAK ISENTROPIC LIFT NOTED AHEAD OF THE 850MB WARM
FRONT...MAINLY OVER THE SW THIRD OF THE FORECAST AREA SUNDAY
EVENING. WHILE MODEL GUIDANCE HAS BEEN FAIRLY CONSISTENT IN
DEPICTING A THREAT FOR ISOLATED/SCATTERED CONVECTION OVER OUR W-SW
COUNTIES BY SUNDAY EVENING...PRESENCE OF MID LEVEL RIDGE OVER OUR
REGION MAY HOLD OFF RAIN THREAT UNTIL LATE SUNDAY NIGHT (4-6 HOURS
LATER THAN MODEL PROJECTIONS). STILL...DO NOT PLAN TO CHANGE LITTLE
FROM PREVIOUS FORECAST AS THERE APPEARS TO BE ENOUGH PARAMETERS IN
PLACE TO WARRANT A SLIGHT-SMALL CHANCE POP FOR SUNDAY NIGHT OVER
ROUGHLY THE SW HALF OF THE CWA. IT WILL BE NOTICEABLY MORE HUMID
ACROSS THE REGION SUNDAY NIGHT WHICH...ALONG WITH
INCREASING/THICKENING CLOUD COVERAGE...WILL LEAD TO OVERNIGHT MINS
3-5 DEGREES WARMER THAN PREVIOUS NIGHTS. MIN TEMPS MID-UPPER 60S.
MONDAY-MONDAY NIGHT...UPPER LEVEL TROUGH OVER THE LOWER MS VALLEY
LATE SUNDAY LIFTS NEWD...NUDGED ALONG BY A DEEPER TROUGH CROSSING
THE NORTHERN PLAINS. BY MON AM...THE SOUTHERN TROUGH WILL BE IN THE
TN VALLEY AND CONTINUE TO INCH SLOWLY ENE. THIS FEATURE WILL CAUSE
AN OPEN FEED OF MOISTURE FROM THE GULF INTO THE CAROLINA.
PERTURBATIONS IN THE SW FLOW AHEAD OF THE TROUGH INTERACTING WITH
THE MOIST AND UNSTABLE AIR MASS WILL TRIGGER ROUNDS OF SHOWERS AND
T-STORMS. EXPECT COVERAGE TO BE GREATEST IN THE WEST VERSUS EAST AS
DEEPER MOISTURE AND BETTER ORGANIZED LIFT WILL RESIDE IN THE WESTERN
PIEDMONT COMPARED TO THE COASTAL PLAIN. HOWEVER THE AIR MASS MAY BE
MORE UNSTABLE IN THE EAST SINCE THIS REGION MAY SEE SOME PARTIAL
SUN. THIS WILL LEAD TO THE POTENTIAL FOR STRONG STORMS IN THE EAST
MONDAY AFTERNOON-MONDAY NIGHT. DUE TO CONVECTION AND CLOUD
COVERAGE...EXPECT AFTERNOON TEMPS TO AVERAGE A FEW DEGREES SHY OF
NORMAL. MAX TEMPS LOW-MID 80S. MIN TEMPS MONDAY NIGHT UPPER 60S TO
NEAR 70.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 AM...
A MID LEVEL TROUGH WILL BE PUSHING EAST OFF THE MOUNTAINS TUESDAY
MORNING WITH CONVERGENT... THOUGH WEAK NEAR SURFACE FLOW AHEAD OF
IT. PRECIPITABLE WATERS WELL ABOVE NORMAL AT AROUND TWO INCHES WITH
POTENTIAL ENERGY RISING ABOVE 2500 JOULES/KILOGRAM. SOME SHOWERS OR
A THUNDERSTORM POSSIBLE ALMOST ANY TIME TUESDAY... BUT CHANCES ARE
CERTAINLY HIGHEST WITH THE HEAT OF THE DAY AND NEAR AND EAST OF THE
MID LEVEL TROUGH (HIGHWAY ONE AND EAST). GIVEN SOMEWHAT SLOW CELL
MOVEMENT A FLOODING THREAT WILL EXIST. AFTERNOON INSTABILITY WILL
PRESENT THE THREAT FOR PRECIPITATION LOADING OF DOWNDRAFTS AND
POSSIBLE DAMAGING WINDS.
THE SURFACE AND MID LEVEL TROUGHS REACH THE COASTAL PLAIN BY SUNRISE
WEDNESDAY... AND WINDS SHIFT TOWARD NORTHEAST DURING THE DAY. THE
AIR COLUMN IN THE WEST DRYS OUT WITH MINIMAL DRYING EAST. POTENTIAL
ENERGY FOR THE AFTERNOON IS FORECAST ABOVE 2500 ACROSS THE AREA.
CONVECTION IN THE WEST COULD BE WIDELY SCATTERED TO ABSENT IF DRYING
ALOFT IS SIGNIFICANT. MORE COVERAGE IN THE EAST BUT POPS NO HIGHER
THAN 50 PERCENT. LOW LEVEL TRIGGERS OTHER THAN HEATING SEEM ABSENT
THOUGH MODELS IN ROUGH AGREEMENT IN A POTENTIAL SHORT WAVE CROSSING
THE AREA DURING THE AFTERNOON. A THREAT FOR DAMAGING WINDS WITH THE
STRONGER THUNDERSTORMS WILL EXIST... BUT THE LIKELIHOOD IS REDUCED
FROM TUESDAY... ESPECIALLY WEST.
WITH LOSS OF HEATING... MOST CONVECTION SHOULD END IN THE EVENING
AND MUCH OF THE NIGHT EXPECTED TO BE DRY.
AFTERNOON HIGH TEMPERATURES WILL BE TRICKY WITH CLOUDS AND
PRECIPITATION TUESDAY. LESS COVERAGE WEDNESDAY BUT NORTHEAST FLOW
WILL TEMPER EXPECTED HIGHS FROM LOW LEVEL THICKNESSES. HIGH
TEMPERATURES MOSTLY MID 80S. LOW TEMPERATURES 65 TO 70 UNDER MUGGY
CONDITIONS.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 304 PM SATURDAY...
12Z GFS TRENDED A BIT FASTER WITH THE EWD TRANSLATION IN THE MID
LEVEL TROUGH...SOMEWHAT SIMILAR FASHION TO THE 00Z ECMWF. WHILE
MAY SEE A LINGERING CHANCE POP IN THE COASTAL PLAIN....ESPECIALLY
THU AFTERNOON....OVERALL TREND WILL BE FOR THE AIR MASS TO
GRADUALLY DRY OUT...LEADING TO LOWER POP CHANCES. BY LATE FRI INTO
SATURDAY...HIGH PRESSURE OVER THE OH VALLEY WILL BEGIN TO EXERT
ITS INFLUENCE ON OUR SENSIBLE WEATHER. WITH FEW
CLOUDS/SHOWERS...EXPECT AFTERNOON TEMPS TO RETURN TO NEAR
NORMAL/SLIGHTLY ABOVE NORMAL LEVELS.
&&
.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
AS OF 215 AM SUNDAY...
CONTINUED RIDGING AT THE SURFACE AND ALOFT WILL MAINTAIN DRY VFR
CONDITIONS THROUGH MOST OF THE 24-HOUR TAF PERIOD. HOWEVER...THE
APPROACH OF A SOUTHERN STREAM WAVE ALOFT AND ASSOCIATED LOW LEVEL
FRONTAL ZONE MAY SPARK A FEW WIDELY SCATTERED SHOWERS IN THE
VICINITY OF KINT/KGSO/KFAY LATE THIS AFTERNOON OR THIS EVENING...BUT
THE BULK OF THIS ACTIVITY WILL LIKELY HOLD NEAR KCLT AND POINTS
SOUTHWESTWARD UNTIL AFTER THE 06Z TAF PERIOD. THE APPROACH OF THE
AFOREMENTIONED LOW LEVEL FRONTAL ZONE WILL ALSO CAUSE MVFR RANGE
STRATUS TO SPREAD NORTHWARD AND AFFECT KINT AND POSSIBLY KGSO BY
AROUND 06Z. GENERALLY LIGHT SOUTH SOUTHWEST SURFACE WINDS WILL
PREVAIL THROUGH THE PERIOD...RELATIVELY STRONGEST BETWEEN 7-11 KTS
THIS AFTERNOON.
LOOKING AHEAD: THE MVFR RANGE STRATUS WILL ADVANCE NORTHEASTWARD AND
AFFECT THE REMAINDER OF CENTRAL NC TERMINALS LATE TONIGHT INTO
MONDAY...COINCIDENT WITH AN INCREASING CHANCE OF SHOWERS AND
ISOLATED THUNDERSTORMS DURING THAT TIME. PERIODS OF MVFR CEILINGS...
AND SHOWERS AND STORMS...WILL THEN LIKELY PERSIST THROUGH
WEDNESDAY...BEFORE A RETURN TO DRIER VFR CONDITIONS BEHIND A COLD
FRONT BY WEDNESDAY NIGHT.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MWS
NEAR TERM...CBL/KRR
SHORT TERM...
LONG TERM...WSS
AVIATION...MWS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
215 AM EDT SUN JUN 10 2012
.SYNOPSIS...
RIDGING AT THE SURFACE AND ALOFT WILL EXTEND ALONG THE SOUTHEAST
COAST THROUGH TONIGHT. MEANWHILE...VERY MOIST AIR ATTENDANT TO A
SOUTHERN STREAM WAVE ALOFT WILL OVERSPREAD THE CAROLINAS FROM THE
SOUTH LATE TONIGHT INTO MONDAY...AND LINGER THROUGH MIDWEEK.
&&
.NEAR TERM /THROUGH SUNDAY/...
AS OF 930 PM SATURDAY...
TONIGHT:
WEAK SOUTHERLY RETURN FLOW HAS DEVELOPED ACROSS THE AREA THIS
EVENING IN RESPONSE TO EASTWARD SHIFT OF A 1019MB SURFACE
OFF THE SOUTHEAST COAST. DEWPOINTS HAVE ALREADY RESPONDED...
RUNNING ANYWHERE FROM 5 TO 10 DEGREE FAHRENHEIT WARMER THAN THIS
SAME TIME LAST NIGHT.
CENTRAL NC WILL CONTINUE TO SEE HIGH LEVEL MOISTURE/CLOUDS SPREAD
INTO THE AREA DOWNSTREAM FROM THE SOUTHERN STREAM WAVE OVER THE NW
GULF OF MEXICO. RUC ANALYSIS SHOWS A FAIRLY WELL-DEFINED VORTICITY
SHEAR AXIS EMANATING NORTHEASTWARD AWAY FROM THE BROAD MID-LEVEL
CIRCULATION AND MOVING TOWARDS THE CAROLINAS THROUGH DAYBREAK.
AS SUCH...EXPECT TO SEE A FAIR AMOUNT OF HIGH CLOUDS OVERNIGHT...
PRODUCING GENERALLY MOSTLY CLOUDY SKIES. THESE CLOUDS AND THE
MODERATING AIRMASS WILL RESULT IN A MUCH MILDER NIGHT WITH MORNING
LOWS PREDOMINATELY IN THE MID 60S. -CBL
FOR SUNDAY...WITH THE MID LEVEL RIDGE PROGGED TO HOLD OVER THE
REGION...THE BEST MOISTURE IS EXPECTED TO STREAM NORTHWARD AND
REMAIN WEST OF THE MOUNTAINS...KEEPING CENTRAL NC MOSTLY DRY.
HOWEVER...THE GFS AND ECMWF HAVE BEEN MORE AGGRESSIVE WITH BRINGING
IN MOISTURE EAST OF THE MOUNTAINS AS THEY WEAKEN THE RIDGE A LITTLE
MORE OVER WESTERN NC. AS A RESULT...THEY SHOW MORE IN THE WAY OF
PRECIP CHANCES MOVING INTO THE EXTREME SOUTHWESTERN PORTIONS OF THE
FORECAST AREA BY LATE SUNDAY AFTERNOON. WILL MAINTAIN THE SLIGHT
CHANCE POP ACROSS THE EXTREME SOUTHWESTERN CWA FOR LATE SUNDAY
AFTERNOON. CLOUDS WILL INCREASE FROM SOUTHWEST TO NORTHEAST
THROUGHOUT THE DAY WITH THE APPROACH OF THE MID LEVEL WAVE. AS A
RESULT...TEMPS WILL LIKELY BE NOT AS WARM ACROSS THE SOUTHWEST
(WHERE THERE WILL BE MORE CLOUDS FOR A LONGER PART OF THE DAY) AND
AM GENERALLY EXPECTING HIGHS TO RANGE FROM THE NEAR 90 DEGREES
ACROSS THE NORTHEAST TO MID/UPPER 80S ACROSS THE SOUTHWEST.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
AS OF 301 PM SATURDAY...
SUNDAY NIGHT...850MB WARM FRONT EXPECTED TO BE DRAPED ACROSS
SC...ITS NWD PROGRESS IMPEDED BY A MID LEVEL RIDGE EXTENDING NW-SE
ACROSS CENTRAL NC. THIS RIDGE EVENTUALLY WEAKENS...ALLOWING THE
850MB WARM FRONT TO EDGE NWD INTO OUR REGION BY EARLY MONDAY.
DEVELOPING S-SW FLOW ALOFT WILL BEGIN TO USHER VERY MOIST AIR INTO
CENTRAL NC. PRECIP WATER VALUES PROJECTED TO INCREASE BY 100 PERCENT
FROM SUNDAY MORNING TO MONDAY MORNING WITH PW VALUES BY EARLY MONDAY
1.5-1.8 INCHES. WEAK ISENTROPIC LIFT NOTED AHEAD OF THE 850MB WARM
FRONT...MAINLY OVER THE SW THIRD OF THE FORECAST AREA SUNDAY
EVENING. WHILE MODEL GUIDANCE HAS BEEN FAIRLY CONSISTENT IN
DEPICTING A THREAT FOR ISOLATED/SCATTERED CONVECTION OVER OUR W-SW
COUNTIES BY SUNDAY EVENING...PRESENCE OF MID LEVEL RIDGE OVER OUR
REGION MAY HOLD OFF RAIN THREAT UNTIL LATE SUNDAY NIGHT (4-6 HOURS
LATER THAN MODEL PROJECTIONS). STILL...DO NOT PLAN TO CHANGE LITTLE
FROM PREVIOUS FORECAST AS THERE APPEARS TO BE ENOUGH PARAMETERS IN
PLACE TO WARRANT A SLIGHT-SMALL CHANCE POP FOR SUNDAY NIGHT OVER
ROUGHLY THE SW HALF OF THE CWA. IT WILL BE NOTICEABLY MORE HUMID
ACROSS THE REGION SUNDAY NIGHT WHICH...ALONG WITH
INCREASING/THICKENING CLOUD COVERAGE...WILL LEAD TO OVERNIGHT MINS
3-5 DEGREES WARMER THAN PREVIOUS NIGHTS. MIN TEMPS MID-UPPER 60S.
MONDAY-MONDAY NIGHT...UPPER LEVEL TROUGH OVER THE LOWER MS VALLEY
LATE SUNDAY LIFTS NEWD...NUDGED ALONG BY A DEEPER TROUGH CROSSING
THE NORTHERN PLAINS. BY MON AM...THE SOUTHERN TROUGH WILL BE IN THE
TN VALLEY AND CONTINUE TO INCH SLOWLY ENE. THIS FEATURE WILL CAUSE
AN OPEN FEED OF MOISTURE FROM THE GULF INTO THE CAROLINA.
PERTURBATIONS IN THE SW FLOW AHEAD OF THE TROUGH INTERACTING WITH
THE MOIST AND UNSTABLE AIR MASS WILL TRIGGER ROUNDS OF SHOWERS AND
T-STORMS. EXPECT COVERAGE TO BE GREATEST IN THE WEST VERSUS EAST AS
DEEPER MOISTURE AND BETTER ORGANIZED LIFT WILL RESIDE IN THE WESTERN
PIEDMONT COMPARED TO THE COASTAL PLAIN. HOWEVER THE AIR MASS MAY BE
MORE UNSTABLE IN THE EAST SINCE THIS REGION MAY SEE SOME PARTIAL
SUN. THIS WILL LEAD TO THE POTENTIAL FOR STRONG STORMS IN THE EAST
MONDAY AFTERNOON-MONDAY NIGHT. DUE TO CONVECTION AND CLOUD
COVERAGE...EXPECT AFTERNOON TEMPS TO AVERAGE A FEW DEGREES SHY OF
NORMAL. MAX TEMPS LOW-MID 80S. MIN TEMPS MONDAY NIGHT UPPER 60S TO
NEAR 70.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 304 PM SATURDAY...
TUESDAY THROUGH WEDNESDAY NIGHT...A SERIES OF MID LEVEL TROUGHS WILL
CROSS THE CAROLINAS THIS PERIOD. THESE FEATURES INTERACTING WITH THE
MOIST AND UNSTABLE AIR MASS IN PLACE WILL SUPPORT SCATTERED TO
NUMEROUS SHOWERS AND T-STORMS. A SURFACE BOUNDARY ASSOCIATED WITH
THE MID LEVEL TROUGH WILL SERVE AS THE FOCUS FOR CONVECTIVE
INITIATION. THIS FEATURE PROJECTED TO ONLY INCH SLOWLY EAST THROUGH
THIS PERIOD. DUE TO THE WEAK WIND FIELD ALOFT...COULD SEE SHOWERS
AND STORMS CROSS REPEATEDLY OVER THE SAME LOCATION...LEADING TO
MINOR FLOODING PROBLEMS. AS ELUDED TO IN THE PREVIOUS FORECAST
DISCUSSION...STORMS THAT DEVELOP IN THE MAIN INSTABILITY AXIS WILL
LIKELY HAVE STRONGER/MORE SUSTAINED UPDRAFTS...LEADING TO PRECIP
LOADING. THIS IN TURN MAY CAUSE A FEW WET MICROBURSTS EACH
AFTERNOON/EARLY EVENING.
CONSIDERABLE AND PERIODS OF CONVECTION WILL AGAIN LEAD TO AFTERNOON
TEMPS A FEW DEGREES COOLER THAN NORMAL THOUGH THE HUMID AIR MASS
WILL MAKE IT FEEL RATHER WARM/STICKY. MAX TEMPS 80-84. MIN TEMPS
UPPER 60S-NEAR 70.
THURSDAY THROUGH SATURDAY...12Z GFS TRENDED A BIT FASTER WITH THE
EWD TRANSLATION IN THE MID LEVEL TROUGH...SOMEWHAT SIMILAR FASHION
TO THE 00Z ECMWF. WHILE MAY SEE A LINGERING CHANCE POP IN THE
COASTAL PLAIN....ESPECIALLY THU AFTERNOON....OVERALL TREND WILL BE
FOR THE AIR MASS TO GRADUALLY DRY OUT...LEADING TO LOWER POP
CHANCES. BY LATE FRI INTO SATURDAY...HIGH PRESSURE OVER THE OH
VALLEY WILL BEGIN TO EXERT ITS INFLUENCE ON OUR SENSIBLE WEATHER.
WITH FEW CLOUDS/SHOWERS...EXPECT AFTERNOON TEMPS TO RETURN TO NEAR
NORMAL/SLIGHTLY ABOVE NORMAL LEVELS.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 215 AM SUNDAY...
CONTINUED RIDGING AT THE SURFACE AND ALOFT WILL MAINTAIN DRY VFR
CONDITIONS THROUGH MOST OF THE 24-HOUR TAF PERIOD. HOWEVER...THE
APPROACH OF A SOUTHERN STREAM WAVE ALOFT AND ASSOCIATED LOW LEVEL
FRONTAL ZONE MAY SPARK A FEW WIDELY SCATTERED SHOWERS IN THE
VICINITY OF KINT/KGSO/KFAY LATE THIS AFTERNOON OR THIS EVENING...BUT
THE BULK OF THIS ACTIVITY WILL LIKELY HOLD NEAR KCLT AND POINTS
SOUTHWESTWARD UNTIL AFTER THE 06Z TAF PERIOD. THE APPROACH OF THE
AFOREMENTIONED LOW LEVEL FRONTAL ZONE WILL ALSO CAUSE MVFR RANGE
STRATUS TO SPREAD NORTHWARD AND AFFECT KINT AND POSSIBLY KGSO BY
AROUND 06Z. GENERALLY LIGHT SOUTH SOUTHWEST SURFACE WINDS WILL
PREVAIL THROUGH THE PERIOD...RELATIVELY STRONGEST BETWEEN 7-11 KTS
THIS AFTERNOON.
LOOKING AHEAD: THE MVFR RANGE STRATUS WILL ADVANCE NORTHEASTWARD AND
AFFECT THE REMAINDER OF CENTRAL NC TERMINALS LATE TONIGHT INTO
MONDAY...COINCIDENT WITH AN INCREASING CHANCE OF SHOWERS AND
ISOLATED THUNDERSTORMS DURING THAT TIME. PERIODS OF MVFR CEILINGS...
AND SHOWERS AND STORMS...WILL THEN LIKELY PERSIST THROUGH
WEDNESDAY...BEFORE A RETURN TO DRIER VFR CONDITIONS BEHIND A COLD
FRONT BY WEDNESDAY NIGHT.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MWS
NEAR TERM...CBL/KRR
SHORT TERM...WSS
LONG TERM...WSS
AVIATION...MWS
AREA FORECAST DISCUSSION
NWS NORMAN OK
631 PM CDT MON JUN 11 2012
.AVIATION...
CONDITIONS WILL MAINLY BE VFR EXCEPT FOR SCATTERED THUNDERSTORMS
AND PERHAPS SOME MVFR CIGS TOMORROW AFTERNOON SOUTH AS WARM FRONT
SLOWLY LIFTS NORTH. SCATTERED THUNDERSTORMS WILL BE POSSIBLE
TONIGHT IN THE SOUTH NEAR THE FRONTAL BOUNDARY... BUT
PROBABILITIES AT TAF SITES ARE TOO LOW FOR A TEMPO GROUP. PROB30
GROUPS ARE INCLUDED IN THE SOUTHWEST OKLAHOMA AND KSPS TAFS FOR
TOMORROW.
&&
.PREV DISCUSSION... /ISSUED 428 PM CDT MON JUN 11 2012/
DISCUSSION...
THE BIGGEST CHALLENGES ARE SEVERE THUNDERSTORM AND RAIN CHANCES
THROUGH WEDNESDAY.
THROUGH 10 PM CDT TONIGHT...BELIEVE THE BEST CHANCES FOR SEVERE
STORMS WILL OVER WESTERN NORTH TEXAS AND POSSIBLY FAR SOUTHERN
OKLAHOMA NEAR A SURFACE BOUNDARY...WHERE KEPT 20/30 PERCENT
CHANCES. STORMS WERE DEVELOPING NEAR ABILENE TEXAS WHERE THE CAP
HAS BEEN BROKEN AND WILL MOVE EAST AND POSSIBLY NORTHEAST. WITH
THE AIR BEING UNSTABLE WITH SOME SHEAR...THINK LARGE
HAIL...POSSIBLY AS LARGE AS BASEBALLS...AND DAMAGING WIND OF 65
MPH OR GREATER WILL BE THE MAIN HAZARDS. MOST OF THESE STORMS WILL
STAY SOUTH OF THE FORECAST AREA. NOTICED THE LATEST HRRR RUNS
INDICATED ISOLATED DEVELOPMENT EAST OF I-35...SO KEPT 20 PERCENT
IN THESE AREAS...THOUGH CONFIDENCE OF DEVELOPMENT REMAINS QUITE
LOW DUE TO STRONG CAPPING.
AFTER 10 PM CDT TONIGHT...KEPT RAIN CHANCES SOUTH OF A CLINTON TO
OKLAHOMA CITY TO SWEETWATER LINE. ADDITIONAL STORMS MAY DEVELOP
NEAR THE LINE MENTIONED ABOVE BETWEEN 10 PM AND 4 AM AS LATEST
MODELS INDICATED THE MID LEVEL CAP WEAKENING WITH 700 MB
TEMPERATURES COOLING TO +9/10C. WITH ABUNDANT INSTABILITY AND A
GOOD AMOUNT OF SHEAR...A FEW STORMS MAY BE SEVERE WITH LARGE
HAIL...POSSIBLY VERY LARGE...AND DAMAGING WIND. THE FOCUS FOR
LIFT APPEARS TO BE WEAK...SO WIDESPREAD SEVERE SEEMS UNLIKELY.
LOCALLY HEAVY RAINFALL MAY BE POSSIBLE AS WELL.
TUESDAY...KEPT RAIN CHANCES ACROSS MUCH OF THE AREA WITH THE
HIGHEST CHANCES OVER SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS
WHERE BEST MOISTURE AND INSTABILITY ARE FORECAST. SOME STORMS
MAY BE SEVERE WITH LARGE HAIL AND DAMAGING WIND...MAINLY DURING
THE LATE AFTERNOON AND EVENING HOURS...THOUGH LARGE HAIL THREAT
MAY BE LOWER COMPARED TO TONIGHT.
WEDNESDAY INTO THURSDAY...KEPT LOWER CHANCES FOR SHOWERS AND
STORMS OVER THE AREA. CANNOT RULE OUT A FEW SEVERE STORMS
BOTH DAYS.
FRIDAY THROUGH NEXT MONDAY...HOTTER AND DRIER WEATHER
IS EXPECTED. A FEW STORMS MAY BE POSSIBLE DURING THIS TIME
FRAME...BUT DID NOT MENTION DUE TO LOW CONFIDENCE.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 68 85 66 86 / 20 20 40 30
HOBART OK 64 87 67 89 / 20 40 40 30
WICHITA FALLS TX 69 88 71 91 / 40 30 50 30
GAGE OK 55 84 62 88 / 0 20 40 30
PONCA CITY OK 60 86 61 86 / 0 0 20 30
DURANT OK 71 87 70 88 / 50 30 40 30
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
1109 AM CDT SUN JUN 10 2012
.DISCUSSION.../ISSUED AT 1109 AM CDT/
VERY COMPLEX SHORT TERM TODAY. FRONTAL ZONE IS NOW STARTING TO
ACCELERATE A BIT...ROUGHLY ALONG A DE SMET TO WAGNER LINE AROUND
1530Z...BASED ON VISIBLE SATELLITE. READINGS AHEAD OF THE BOUNDARY
HAVE JUMPED NICELY ON THE STRONG SOUTH/SOUTHWEST WINDS...REACHING
LOWER 80S BY MID MORNING. DID END UP RAISING HIGHS BY SEVERAL
DEGREES EAST OF THE JAMES RIVER...ESPECIALLY THROUGH EASTERN AREAS
WHERE SUNSHINE WILL LAST THE LONGEST. ALSO RAISED DEWPOINTS SOMEWHAT
FOR THE TYPICAL MORNING PRE MIXING RISE...BUT RATHER THAN CRASH WITH
MIXING...CAP SHOULD RESULT IN MORE OF A LEVELING OUT UNTIL FRONTAL
PASSAGE THIS TIME AROUND. IN FACT...CAP THROUGH AT LEAST EARLY TO
MID AFTERNOON SHOULD PRECLUDE THREAT FOR CONVECTION AT OR AHEAD OF
THE SURFACE BOUNDARY...WITH ANYTHING MORE LIKELY TO BE ISOLATED
ELEVATED WELL POSTFRONTAL SHOWERS...AND THIS HAS BEEN FEATURE OF
SEVERAL HRRR RUNS THROUGH THE MORNING...IF NOT A BIT OVERDONE EVEN
ON THIS.
ACTUAL PRE FRONTAL CONDITIONS MAY BE A BIT WARMER...BUT BIT LESS
MOIST...THAN MOST MODEL SOLUTIONS...WHICH IN THE END LOOKS TO BE A
PUSH AS FAR AS CAP STRENGTH. AS MID LEVEL TROUGH NUDGES IN FROM THE
WEST AND TEMPS IN THE MID LEVELS START TO SLIP...AND THIS SHOULD
OPEN THE DOOR FOR SOME CONVECTIVE UPTAKE ALONG THE EASTERN EDGE OF
THE CLOUD SHIELD CLOSER TO THE SURFACE FRONTAL BOUNDARY. WILL LIKELY
WILL END UP WITH A FAIRLY NARROW ZONE NEAR TO SLIGHTLY BEHIND FRONT
WHERE THREAT FOR SEVERE WILL BE LOCATED...BETWEEN THE CAP HOLDING
EAST OF THE FRONT...AND THE AREA TOO POSTFRONTAL TO THE WEST.
INCREASE IN MID LEVEL WINDS WILL LENGTHEN OUT THE HODOGRAPHS...WITH
DIRECTIONAL SHEAR NOT TOO IMPRESSIVE AT ALL. LOOKS MAINLY TO BE A
HAIL/WIND THREAT WITH STORMS...WHICH SHOULD BE CLEAR OF CWA AROUND
02Z.
FAIRLY NON-DIURNAL TRACES AS WELL WITH STRONG POST FRONTAL FALL...
BUT INDICATIONS NOW WITH CLEARING LINE LIKELY TO PRESS TO THE JAMES
VALLEY BY 22Z THAT FAR WEST WILL BE ABLE TO RECOVER QUITE A BIT
MORE...AND MIXING VALUES ON NAM/RAP SUGGEST MID TO UPPER 70S. SHADED
A BIT LOWER THAN THAT...BUT DID RESULT IN A 4-6F BUMP IN THE FAR
WEST DURING THE AFTERNOON...WITH HIGHS SKEWED THERE TOWARD 00Z. /CHAPMAN
&&
.AVIATION.../FOR THE 12Z TAF ISSUANCE/
COLD FRONT WILL PUSH ACROSS THE AREA TODAY WITH A COMPLEX AVIATION
FORECAST. WINDS WILL BE GUSTY OUT OF THE SOUTH AHEAD OF THE FRONT
WITH GUSTS AROUND 25 KTS EXPECTED. WINDS WILL TURN WEST THEN
NORTHWEST BEHIND THE FRONT AND GUST AGAIN AROUND 25 KTS. TIMING OF
THE FRONT PUTS IT THROUGH KHON AROUND 12Z...KFSD AND KSUX IN THE
17-19Z TIME FRAME...AND EAST OF THE CWA BY AROUND 22Z. WINDS
EXPECTED TO BECOME LIGHTER OVERNIGHT TONIGHT...AND TURN BACK TO MORE
OF A SOUTHERLY DIRECTION. LOW LEVEL JET IN THE PROCESS OF
WEAKENING...SO REMOVED LLWS FROM THE TAFS.
THUNDERSTORM CHANCES LOOK LOW AHEAD OF THE FRONT WITH A STRONG CAP
IN PLACE. HOWEVER SHOWERS AND THUNDERSTORMS SHOULD BEGIN TO DEVELOP
ON THE COOL SIDE OF THE FRONT THIS AFTERNOON AND EVENING ALONG AND
EAST OF INTERSTATE 29. THIS PUTS KFSD AND KSUX ON THE BOUNDARY OF
WHERE STORMS ARE EXPECTED TO FORM. KSUX MAY HAVE A SLIGHTLY BETTER
CHANCE SO INCLUDED A TEMPO TSRA THERE...WITH ONLY SHRA MENTIONED IN
THE KFSD TAF. WILL HAVE TO MONITOR TRENDS THIS MORNING AND AFTERNOON
AS ELEVATED INSTABILITY ENOUGH THAT COULD SEE THUNDER AT KFSD IF CAP
BREAKS IN TIME.
OTHER ISSUE THIS PERIOD IS POSSIBLE STRATUS BEHIND THE FRONT. RATHER
LOW CONFIDENCE...BUT LOOKS LIKE A NARROW CORRIDOR OF MVFR CIGS
BEHIND THE FRONT. SO COULD SEE A REDUCTION FOR A FEW HOURS AT KHON
THIS MORNING AND KFSD THIS AFTERNOON. THINKING IS THAT THESE WILL
ONLY LAST A FEW HOURS...WITH DRIER AIR QUICKLY PUSHING IN RAISING
CIGS BACK INTO THE VFR CATEGORY. /CHENARD
&&
.PREV DISCUSSION.../ISSUED AT 310 AM CDT/
COLD FRONT PUSHING INTO FAR WESTERN CWA AS OF 08Z AND SHOULD
CONTINUE TO PUSH EAST TODAY...REACHING I29 BY 17Z AND EXIT FAR
EASTERN CWA BY 00Z. FIRST WAVE OF THUNDERSTORMS SLIDING OFF TO
NORTHEAST JUST WEST OF CWA AS WAVE LIFTS NORTHEAST INTO ND. SO MAY
NOT SEE MUCH ACTIVITY MOST OF MORNING ALTHOUGH CAN NOT RULE OUT
ISOLATED SHOWERS REDEVELOPING JUST BEHIND FRONT. WILL LIKELY SEE
THUNDERSTORM REDEVELOPMENT ALONG AND EAST OF I29 THIS AFTERNOON AS
SECOND WAVE LIFTS NORTHEAST ACROSS EASTERN NEBRASKA. THUNDERSTORM
ACTIVITY WILL LIKELY DEVELOP JUST BEHIND FRONT AS CAP WILL EXIST TO
THE EAST. SEVERE THREAT WILL BE LIMITED TO AREAS EAST OF I29 THIS
AFTERNOON WITH BEST CHANCE BETWEEN 19Z AND 22Z. WILL ALSO SEE PLENTY
OF STRATUS SPREAD IN BEHIND THE FRONT SO SKIES WILL BECOME MOSTLY
CLOUDY BEHIND FRONT. HIGH TEMPERATURES WEST OF I29 LIKELY TO OCCUR
IN THE MORNING...AND THEN HOLD STEADY OF FALL A BIT. ALSO EXPECT
GUSTY SOUTH WINDS AHEAD OF FRONT REPLACED BY GUSTY NORTHWEST WINDS
AS FRONT MOVES THROUGH.
SHOULD BE DRY AND PLEASANT TONIGHT AND MONDAY AND AGAIN BREEZY ON
MONDAY BEHIND SECOND SHORT WAVE. POTENTIAL EXISTS FOR ISOLATED
AFTERNOON SHOWERS ACROSS THE NORTHERN CWA...BUT WITH CHANCE LESS
THAN 20%...WILL LEAVE DRY.
THE COOL WEATHER WILL REMAIN IN PLACE TUESDAY WITH ANOTHER SHORT
WAVE LIFTING WARM FRONT INTO SOUTHERN CWA TUESDAY NIGHT. WILL
PROBABLY SEE A LEAST A FEW THUNDERSTORMS DEVELOPING NEAR THE
BOUNDARY DURING THE NIGHT AND MOVE EAST ACROSS THE CWA AS LOW LEVEL
JET DEVELOPS. SO WILL KEEP CHANCE OF STORMS IN FORECAST LATER
TUESDAY NIGHT INTO WEDNESDAY WITH THIS FEATURE. WILL BE WARMER ON
WEDNESDAY...BUT EXTENT OF WARMING ACROSS EAST WILL DEPEND ON HOW
FAST ANY STORMS THAT DO DEVELOP TUESDAY NIGHT MOVE OUT OF CWA.
WILL GENERALLY KEEP WEDNESDAY NIGHT AND THURSDAY DRY WITH WARMER
TEMPERATURES EXPECTED. LOOKS UNSETTLED FRIDAY INTO SATURDAY AS
ANOTHER WAVE AND BOUNDARY MOVES ACROSS THE REGION. APPEARS A MORE
ACTIVE WEATHER PATTERN WILL DEVELOP THIS WEEKEND AND CONTINUE INTO
NEXT WEEK AS STRONGER ZONAL FLOW DEVELOPS OVER THE NORTHERN
PLAINS.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
1128 PM MDT SAT JUN 9 2012
.AVIATION...06Z TAFS
SCATTERED SHRA/TSRA WILL CONTINUE ACROSS AREA OVERNIGHT WITH
LOCALIZED IFR CIGS/VSBYS IN THE STRONGEST STORMS. A COLD FRONT IS
EXITING THE AREA VIA NE AND WILL LEAVE GUSTY NORTHWEST/WEST WINDS
IN IT/S WAKE. AREAS MVFR CIGS BEHIND THE FRONT ARE
POSSIBLE...ESPECIALLY ACROSS NORTHEAST WY/NORTHWEST SD.
&&
.PREV DISCUSSION... /ISSUED 1029 PM MDT SAT JUN 9 2012/
DISCUSSION...CURRENT SURFACE ANALYSIS HAS PRIMARY COLD FRONT
STRETCHING FROM EASTERN ND THROUGH SOUTH CENTRAL SD INTO WESTERN
NEB. SECONDARY COLD FRONT IS MOVING THROUGH WESTERN SD. UPPER
LEVEL ANALYSIS SHOWS LOW OVER SOUTHEAST ALBERTA WITH STRONG JET
WRAPPING NORTHEASTWARD ACROSS NORTHEASTERN WY INTO SOUTHEASTERN MT.
EXPLOSIVE DEVELOPMENT OF THUNDERSTORMS HAS OCCURRED OVER THE LAST
COUPLE OF HOURS FOR AREAS FROM THE BLACK HILLS AREA THROUGH WEST
CENTRAL SD AS SECONDARY FRONT REACHED MUCH MORE UNSTABLE AIR IN
PLACE OVER THESE AREAS. SEVERE THUNDERSTORM WATCH HAS BEEN ISSUED
FOR MUCH OF SOUTHWEST SD INTO CENTRAL SD UNTIL LATE TONIGHT.
SECONDARY AREA OF SHOWERS AND STORMS ASSOCIATED WITH UPPER JET IS
TRACKING ACROSS NORTHEASTERN WY...SOUTHEASTERN MT...AND INTO FAR
NORTHWESTERN SD.
HAVE UPDATED TO RAISE POPS ACROSS MUCH OF THE AREA...ESPECIALLY
LATE THIS EVENING. ACTIVITY SHOULD BEGIN TO TAPER OFF AROUND OR
SHORTLY AFTER MIDNIGHT OVER NORTHEASTERN WY AND FAR WESTERN SD.
STRONG TO SEVERE STORMS WILL CONTINUE TO DEVELOP AND TRACK ACROSS
MUCH OF WEST CENTRAL INTO CENTRAL SD OVERNIGHT.
PREV DISCUSSION... /ISSUED 302 PM MDT SAT JUN 9 2012/
DISCUSSION...CURRENT SURFACE ANALYSIS SHOWS LOW PRESSURE OVER
CENTRAL ND...WITH SLOW MOVING OR NEARLY STATIONARY COLD FRONT
STRETCHING SOUTH-SOUTHWESTWARD INTO CENTRAL SD AND WESTERN NEB.
UPPER LEVEL ANALYSIS SHOWS LOW OVER SOUTHWEST ALBERTA...WITH
STRONG JET WRAPPING AROUND THE SYSTEM FROM THE OREGON COAST TO
WESTERN WY AND EASTERN MT. REGIONAL RADARS SHOWING BAND OF
SHOWERS AND SOME THUNDER...ASSOCIATED WITH UPPER JET...CROSSING
NORTH CENTRAL WY INTO PARTS OF SOUTHEASTERN MT. STORMS ARE
BEGINNING TO DEVELOP FURTHER WEST OVER THE ROCKIES. BRISK NORTH-
NORTHWEST WINDS CONTINUE BEHIND THE FRONT ACROSS PORTIONS OF THE
WESTERN SD PLAINS...WITH BREEZY SOUTHERLY WINDS AHEAD OF THE FRONT
ACROSS FAR SOUTH CENTRAL SD. SKIES ARE MOSTLY SUNNY WITH TEMPS
RANGING FROM THE 70S OVER NORTHEASTERN WY AND THE BLACK HILLS TO
THE MID 90S OVER PORTIONS OF SOUTH CENTRAL SD.
AS UPPER LOW MOVES EAST ALONG THE CANADIAN/MONTANA BORDER
TONIGHT...STRONG UPPER LEVEL JET ENERGY WILL MOVE NORTHEAST ACROSS
THE NORTHERN PLAINS TONIGHT. THIS WILL BRING A GOOD CHANCE OF
SHOWERS AND STORMS TO MUCH OF THE AREA...ESPECIALLY NORTHEASTERN
WY...THE BLACK HILLS...AND NORTHWESTERN SD. CHANCES FOR PCPN WILL
DECREASE FURTHER TO THE SOUTH AND EAST...BUT THREAT FOR SEVERE
STORMS WILL LIKELY BE HIGHER IN THIS AREA TONIGHT...ESPECIALLY
TOWARD SOUTH CENTRAL SD. CAPE VALUES OF UP TO 3000 J/KG ARE
PROGGED FOR SOUTH CENTRAL SD THIS EVENING WITH SHEAR INCREASING
DUE TO STRENGTHENING LOW LEVEL JET. MAIN THREATS FROM ANY SEVERE
STORMS WILL BE LARGE HAIL AND STRONG WIND GUSTS.
A TIGHT PRESSURE GRADIENT WILL DEVELOP OVERNIGHT ACROSS WESTERN SD
AS MAIN COLD FRONT FINALLY PUSHES EAST OF THE CWA AND SECONDARY
SURGE OF COOLER AIR BEGINS TO MOVE IN. SHORT RANGE MODELS DISAGREE
SOME ON POTENTIAL STRENGTH OF WINDS OVERNIGHT. NAM AND RUC ARE
STRONGEST WITH THE WINDS...SHOWING POTENTIAL FOR A BRIEF PERIOD
OF WARNING CRITERIA WINDS OVER THE RAP AREA AND ADJACENT PLAINS.
HAVE DECIDED TO ISSUE A WIND ADVISORY FOR MUCH OF THE NORTHWESTERN
AND WEST CENTRAL PLAINS. WINDS SHOULD BEGIN TO DIMINISH SOME LATE
TONIGHT OR EARLY SUNDAY.
BREEZY TO WINDY CONDITIONS WILL LINGER INTO SUNDAY ACROSS MUCH OF
THE AREA...WITH COOLER AND DRIER AIR IN PLACE. WILL KEEP CHANCES
FOR A FEW SHOWERS ACROSS NORTHERN PORTIONS OF THE AREA AS UPPER
LOW PASSES TO THE NORTH. HIGHS WILL BE IN THE 60S TO MID 70S WITH
PARTLY CLOUDY TO MOSTLY SUNNY SKIES. SUNDAY NIGHT WILL BE
PLEASANTLY COOL...WITH LOWS IN THE 40S AND LOWER 50S.
SEASONABLY MILD AND BREEZY WEATHER WILL CONTINUE ON MONDAY...WITH
HIGHS IN THE UPPER 60S AND 70S FOR MOST AREAS. NORTHWESTERLY FLOW
ALOFT WILL BRING SOME WEAK UPPER LEVEL ENERGY ACROSS NORTHERN AND
WESTERN PORTIONS OF THE CWA...SO WILL KEEP SOME LOW CHANCE POPS
FOR SHOWERS AND POSSIBLY A THUNDERSTORM OR TWO DURING THE DAY.
EXTENDED...MAINLY ZONAL FLOW WITH A BUILDING THERMAL RIDGE WILL
RESULT IN A DAILY CHANCE FOR TSTMS ALONG WITH WARMING TEMPS THROUGH
MID WEEK. SW FLOW ALOFT WILL DEVELOP FOR THE END OF THE WEEK AS A
DEEP UPPER TROF MOVES THROUGH THE WRN CONUS. THIS MAY LEAD TO
INCREASED CHANCE FOR TSTMS...WITH TEMPS STAYING QUITE WARM.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WIND ADVISORY UNTIL 6 AM MDT SUNDAY FOR BUTTE-CUSTER CO PLAINS-
HERMOSA FOOT HILLS-NORTHERN MEADE CO PLAINS-PENNINGTON CO
PLAINS-RAPID CITY-SOUTHERN MEADE CO PLAINS-STURGIS/PIEDMONT
FOOT HILLS.
WY...NONE.
&&
$$
SHORT TERM...WFO UNR
LONG TERM....WFO UNR
AVIATION...HELGESON
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
1029 PM MDT SAT JUN 9 2012
.DISCUSSION...CURRENT SURFACE ANALYSIS HAS PRIMARY COLD FRONT
STRETCHING FROM EASTERN ND THROGH SOUTH CENTRAL SD INTO WESTERN
NEB. SECONDARY COLD FRONT IS MOVING THROUGH WESTERN SD. UPPER
LEVEL ANALYSIS SHOWS LOW OVER SOUTHEAST ALBERTA WITH STRONG JET
WRAPPING NORTHEASTWARD ACROSS NORTHEASTERN WY INTO SOUTHEASTERN MT.
EXPLOSIVE DEVELOPMENT OF THUNDERSTORMS HAS OCCURRED OVER THE LAST
COUPLE OF HOURS FOR AREAS FROM THE BLACK HILLS AREA THROUGH WEST
CENTRAL SD AS SECONDARY FRONT REACHED MUCH MORE UNSTABLE AIR IN
PLACE OVER THESE AREAS. SEVERE THUNDERSTORM WATCH HAS BEEN ISSUED
FOR MUCH OF SOUTHWEST SD INTO CENTRAL SD UNTIL LATE TONIGHT.
SECONDARY AREA OF SHOWERS AND STORMS ASSOCIATED WITH UPPER JET IS
TRACKING ACROSS NORTHEASTERN WY...SOUTHEASTERN MT...AND INTO FAR
NORTHWESTERN SD.
HAVE UPDATED TO RAISE POPS ACROSS MUCH OF THE AREA...ESPECIALLY
LATE THIS EVENING. ACTIVITY SHOULD BEGIN TO TAPER OFF AROUND OR
SHORTLY AFTER MIDNIGHT OVER NORTHEASTERN WY AND FAR WESTERN SD.
STRONG TO SEVERE STORMS WILL CONTINUE TO DEVELOP AND TRACK ACROSS
MUCH OF WEST CENTRAL INTO CENTRAL SD OVERNIGHT.
&&
AVIATION...00Z TAFS UPDATE
SHRA/TSTMS WILL CONTINUE ACROSS MUCH OF NORTHEASTERN WY AND
WESTERN SD FOR THE NEXT COUPLE OF HOURS. ISOLATED TO SCATTERED
STORMS WILL ALSO DEVELOP OVER SOUTH CENTRAL SD OVER THE NEXT
FEW HOURS. SOME OF THE STORMS COULD BE SEVERE FROM SOUTHWEST INTO
CENTRAL SD. AREAS OF MVFR CONDITIONS CAN BE EXPECTED. STRONG WINDS
WILL CONTINUE ACROSS THE NORTHWEST AND WEST CENTRAL SD PLAINS
OVERNIGHT BEHIND SECONDARY COLD FRONT. GUSTS OVER 40KTS POSSIBLE...
WITH THE STRONGEST WINDS ALONG THE ERN SLOPES OF THE BLKHLS
INCLUDING THE KRAP TERMINAL. A PERIOD OF MVFR CIGS WILL ALSO BE
POSSIBLE OVER PORTIONS OF NE WY EARLY SUN MORNING...INCLUDING THE
KGCC TERMINAL.
&&
PREV DISCUSSION... /ISSUED 302 PM MDT SAT JUN 9 2012/
DISCUSSION...CURRENT SURFACE ANALYSIS SHOWS LOW PRESSURE OVER
CENTRAL ND...WITH SLOW MOVING OR NEARLY STATIONARY COLD FRONT
STRETCHING SOUTH-SOUTHWESTWARD INTO CENTRAL SD AND WESTERN NEB.
UPPER LEVEL ANALYSIS SHOWS LOW OVER SOUTHWEST ALBERTA...WITH
STRONG JET WRAPPING AROUND THE SYSTEM FROM THE OREGON COAST TO
WESTERN WY AND EASTERN MT. REGIONAL RADARS SHOWING BAND OF
SHOWERS AND SOME THUNDER...ASSOCIATED WITH UPPER JET...CROSSING
NORTH CENTRAL WY INTO PARTS OF SOUTHEASTERN MT. STORMS ARE
BEGINNING TO DEVELOP FURTHER WEST OVER THE ROCKIES. BRISK NORTH-
NORTHWEST WINDS CONTINUE BEHIND THE FRONT ACROSS PORTIONS OF THE
WESTERN SD PLAINS...WITH BREEZY SOUTHERLY WINDS AHEAD OF THE FRONT
ACROSS FAR SOUTH CENTRAL SD. SKIES ARE MOSTLY SUNNY WITH TEMPS
RANGING FROM THE 70S OVER NORTHEASTERN WY AND THE BLACK HILLS TO
THE MID 90S OVER PORTIONS OF SOUTH CENTRAL SD.
AS UPPER LOW MOVES EAST ALONG THE CANADIAN/MONTANA BORDER
TONIGHT...STRONG UPPER LEVEL JET ENERGY WILL MOVE NORTHEAST ACROSS
THE NORTHERN PLAINS TONIGHT. THIS WILL BRING A GOOD CHANCE OF
SHOWERS AND STORMS TO MUCH OF THE AREA...ESPECIALLY NORTHEASTERN
WY...THE BLACK HILLS...AND NORTHWESTERN SD. CHANCES FOR PCPN WILL
DECREASE FURTHER TO THE SOUTH AND EAST...BUT THREAT FOR SEVERE
STORMS WILL LIKELY BE HIGHER IN THIS AREA TONIGHT...ESPECIALLY
TOWARD SOUTH CENTRAL SD. CAPE VALUES OF UP TO 3000 J/KG ARE
PROGGED FOR SOUTH CENTRAL SD THIS EVENING WITH SHEAR INCREASING
DUE TO STRENGTHENING LOW LEVEL JET. MAIN THREATS FROM ANY SEVERE
STORMS WILL BE LARGE HAIL AND STRONG WIND GUSTS.
A TIGHT PRESSURE GRADIENT WILL DEVELOP OVERNIGHT ACROSS WESTERN SD
AS MAIN COLD FRONT FINALLY PUSHES EAST OF THE CWA AND SECONDARY
SURGE OF COOLER AIR BEGINS TO MOVE IN. SHORT RANGE MODELS DISAGREE
SOME ON POTENTIAL STRENGTH OF WINDS OVERNIGHT. NAM AND RUC ARE
STRONGEST WITH THE WINDS...SHOWING POTENTIAL FOR A BRIEF PERIOD
OF WARNING CRITERIA WINDS OVER THE RAP AREA AND ADJACENT PLAINS.
HAVE DECIDED TO ISSUE A WIND ADVISORY FOR MUCH OF THE NORTHWESTERN
AND WEST CENTRAL PLAINS. WINDS SHOULD BEGIN TO DIMINISH SOME LATE
TONIGHT OR EARLY SUNDAY.
BREEZY TO WINDY CONDITIONS WILL LINGER INTO SUNDAY ACROSS MUCH OF
THE AREA...WITH COOLER AND DRIER AIR IN PLACE. WILL KEEP CHANCES
FOR A FEW SHOWERS ACROSS NORTHERN PORTIONS OF THE AREA AS UPPER
LOW PASSES TO THE NORTH. HIGHS WILL BE IN THE 60S TO MID 70S WITH
PARTLY CLOUDY TO MOSTLY SUNNY SKIES. SUNDAY NIGHT WILL BE
PLEASANTLY COOL...WITH LOWS IN THE 40S AND LOWER 50S.
SEASONABLY MILD AND BREEZY WEATHER WILL CONTINUE ON MONDAY...WITH
HIGHS IN THE UPPER 60S AND 70S FOR MOST AREAS. NORTHWESTERLY FLOW
ALOFT WILL BRING SOME WEAK UPPER LEVEL ENERGY ACROSS NORTHERN AND
WESTERN PORTIONS OF THE CWA...SO WILL KEEP SOME LOW CHANCE POPS
FOR SHOWERS AND POSSIBLY A THUNDERSTORM OR TWO DURING THE DAY.
EXTENDED...MAINLY ZONAL FLOW WITH A BUILDING THERMAL RIDGE WILL
RESULT IN A DAILY CHANCE FOR TSTMS ALONG WITH WARMING TEMPS THROUGH
MID WEEK. SW FLOW ALOFT WILL DEVELOP FOR THE END OF THE WEEK AS A
DEEP UPPER TROF MOVES THROUGH THE WRN CONUS. THIS MAY LEAD TO
INCREASED CHANCE FOR TSTMS...WITH TEMPS STAYING QUITE WARM.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WIND ADVISORY UNTIL 6 AM MDT SUNDAY FOR BUTTE-CUSTER CO PLAINS-
HERMOSA FOOT HILLS-NORTHERN MEADE CO PLAINS-PENNINGTON CO
PLAINS-RAPID CITY-SOUTHERN MEADE CO PLAINS-STURGIS/PIEDMONT
FOOT HILLS.
WY...NONE.
&&
$$
SHORT TERM...26
AVIATION...26
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
1043 PM CDT MON JUN 11 2012
.UPDATE...
EARLIER FORECAST IS BASICALLY ON TRACK...ALTHOUGH DID UPDATE TO
ADJUST POPS SLIGHTLY BASED ON THE LATEST HRRR MODEL. INCREASED THE
POPS SLIGHTLY FOR TONIGHT MAINLY FROM EAST CENTRAL AR INTO
NORTHWEST MS AND LOWERED THEM SLIGHTLY MOST OTHER LOCATIONS.
THUNDERSTORMS ASSOCIATED WITH THE MESOSCALE CONVECTIVE SYSTEM THAT
PLOWED THROUGH THE MIDSOUTH EARLIER TODAY NOW STRETCH FROM
NORTHERN LA ACROSS CENTRAL MS INTO CENTRAL AL. THE ATMOSPHERE
ACROSS THE MIDSOUTH IS RAIN COOLED WITH SURFACE BASED INSTABILITY
NIL. HOWEVER...ELEVATED INSTABILITY OF ABOUT 1500 TO 2000 J/KG
EXIST TO OUR WEST AND SOUTHWEST WITH 00Z 850 MB ANALYSIS SHOWING A
SOUTHWEST LY LOW LEVEL FLOW. SCATTERED SHOWERS AND THUNDERSTORMS
HAVE ALREADY BEGUN TO FORM IN CENTRAL AR. THE HRRR MODEL INDICATES
THUNDERSTORMS WILL CONTINUE TO INCREASE THROUGH THIS AREA
(POSSIBLY DEVELOPING INTO A MESOSCALE CONVECTIVE SYSTEM) AND
SLIDE TO THE SOUTHEAST SKIRTING EAST-CENTRAL AR AND NORTHWEST MS.
A FEW STRONG ELEVATED THUNDERSTORMS STILL WITH WIND GUSTS UP TO 45
MPH AND SMALL HAIL STILL LOOK POSSIBLE MAINLY FROM EAST CENTRAL
AR INTO PORTIONS OF NORTH MS. OTHERWISE A COLD FRONT WILL MOVE
INTO NORTHEAST AR AND THE MO BOOTHEEL BY LATE TONIGHT...A FEW
SHOWERS AND THUNDERSTORMS MAY DEVELOP ALONG AND AHEAD OF THE FRONT
LATER TONIGHT.
TEMPERATURES HAVE COOLED INTO THE MIDDLE 60S ACROSS MUCH OF THE
MIDSOUTH. READINGS MAY DROP A DEGREE OR TWO MORE BUT MAINLY WILL
REMAIN STEADY.
JCL
&&
.DISCUSSION...
PREV DISCUSSION... /ISSUED 711 PM CDT MON JUN 11 2012/
UPDATED TO LOWER POPS ACROSS THE MID SOUTH FOR THIS EVENING AND
CLEAR SEVERE THUNDERSTORM WATCH #373 FOR THE ENTIRE AREA.
THE SEVERE LINE OF THUNDERSTORMS THAT MOVES SOUTH ACROSS THE AREA
THIS AFTERNOON AND EVENING HAS NOW EXITED OUR AREA. STRATIFORM
RAIN BEHIND THE SEVERE CONVECTION WILL PERSIST FOR A FEW HOURS AT
MOST AND MAINTAINED LIKELY POPS OVER NORTH MISSISSIPPI TO ACCOUNT
FOR THIS. ELSEWHERE HAVE LOWERED POPS FOR THIS EVENING.
LATER TONIGHT...LATEST HIGH RESOLUTION RAPID REFRESH MODEL
INDICATES ADDITIONAL DEVELOPMENT OF CONVECTION OVER WESTERN
ARKANSAS ALONG STALLED OUTFLOW BOUNDARY. THIS CONVECTION MAY MOVE
BACK OVER SOUTHERN PORTIONS OF THE FORECAST AREA AFTER MIDNIGHT.
THE CURRENT FORECAST HAD ACCOUNTED FOR THIS ACTIVITY BUT
CONFIDENCE IS RATHER LOW. THE ATMOSPHERE MAY BE TOO WORKED OVER
FROM THIS EVENINGS CONVECTION OR NEW CONVECTION MAY BE ELEVATED
OVER THE DECAYING COLD POOL. LATER UPDATES MAY BE NEEDED AS THE
EVENTUAL EVOLUTION BECOMES MORE CLEAR.
UPDATED ZONES...GRIDS...AND HWO HAVE BEEN SENT.
JLH
PREV DISCUSSION... /ISSUED 320 PM CDT MON JUN 11 2012/
A SEVERE FORWARD PROPAGATING MESOSCALE CONVECTIVE SYSTEM (MCS)
CURRENTLY ACROSS NORTHWEST TENNESSEE INTO EASTERN ARKANSAS WILL
CONTINUE TO RACE SOUTHEASTWARD THROUGH THE REMAINDER OF THE
AFTERNOON AND EVENING HOURS. THIS LINE HAS HAD A HISTORY OF WIND
DAMAGE AND THE PRE-CONVECTIVE ENVIRONMENT REMAIN FAVORABLE FOR
CONTINUED WIND DAMAGE WITH MLCAPES IN EXCESS OF 4000 J/KG. THIS
MCS CONTINUES TO MOVE ALONG THE NORTHEAST PERIPHERY OF STRONGER
CAPPING/EML OVER THE ARKLATEX REGION. THIS LINE OF SEVERE
THUNDERSTORMS SHOULD MOVE THROUGH THE REMAINDER OF THE FORECAST
AREA THROUGH THE EVENING.
LATER TONIGHT...THE FORECAST BECOMES MORE UNCERTAIN AS THE
ATMOSPHERE WILL INITIALLY BE WORKED OVER FROM THIS AFTERNOONS MCS.
THE CONVECTIVE OUTFLOW BOUNDARY SLOWS QUITE A BIT ACROSS NORTH-
CENTRAL ARKANSAS AND THIS AREA MAY BE PRIMED FOR REDEVELOPMENT
LATER THIS EVENING...WITH THE ATMOSPHERE POTENTIALLY RELOADING
ACROSS SOUTHWESTERN PORTIONS OF THE AREA. LATEST MODEL GUIDANCE
HINTS AT THIS OCCURENCE...BUT TIMING CONTINUES TO BE A PROBLEM AS
LATEST HRRR IS FASTER WITH MOST CONVECTION PRIOR TO 06Z AND ALL
OTHER MODEL GUIDANCE NOW SLOWER AND LINGERING CONVECTION THROUGH
THE NIGHT OVER THESE LOCATIONS. PLAN TO CARRY LIKELY POPS OVER THE
SOUTH AND WEST AFTER 06Z AND WILL MAINTAIN A SEVERE THREAT FOR
DAMAGING WINDS AND LARGE HAIL.
OVERNIGHT ACTIVITY SHOULD WANE LATE TONIGHT WITH SCATTERED
THUNDERSTORM REDEVELOPMENT POSSIBLE ALONG A SOUTHWARD MOVING COLD
FRONT ALONG THE I-40 CORRIDOR BY MID MORNING. THIS FRONT WILL
CONTINUE TO DROP SOUTH THROUGH EASTERN ARKANSAS AND NORTHERN
MISSISSIPPI BY AFTERNOON WITH THUNDERSTORM ACTIVITY BECOMING MORE
NUMEROUS IN COVERAGE. THE ATMOSPHERE WILL AGAIN DESTABILIZE OVER
THE SOUTHERN HALF OF THE AREA WITH STRONG TO POTENTIALLY SEVERE
STORMS AGAIN POSSIBLE.
THE COLD FRONT WILL MOVE THROUGH THE MID SOUTH BY TUESDAY NIGHT
WITH SURFACE HIGH PRESSURE BUILDING OVER THE AREA. THE FRONT
SHOULD STALL ACROSS CENTRAL MISSISSIPPI AS UPPER LEVEL HEIGHTS
RISE. DRY AND VERY WARM WEATHER CAN BE EXPECTED WEDNESDAY THROUGH
FRIDAY MORNING. THE FRONT WILL RETURN BACK TO THE NORTH AS A WARM
FRONT BY FRIDAY ALLOWING FOR A DEEP TROPICAL MOISTURE TO ADVANCE
BACK INTO THE MID SOUTH. ISOLATED SHOWERS AND THUNDERSTORMS WILL
AGAIN BE POSSIBLE DURING PEAK HEATING ON BOTH FRIDAY AND SATURDAY.
A DRIER AIRMASS WILL WORK INTO THE AREA BY SUNDAY HELPING TO LIMIT
DIURNAL CONVECTION. TEMPERATURES WILL REMAIN SEASONALLY WARM WITH
INCREASING HUMIDITY LEVELS THROUGH THE END OF THE EXTENDED
FORECAST PERIOD.
JLH
&&
.AVIATION...
00Z TAFS
SQUALL TO SOUTH OF AREA. SOME STRATIFORM RAIN BEHIND SYSTEM WILL
LINGER FOR A COUPLE HOURS IN MOST AREAS. SOME MIST/FOG MAY DEVELOP
TONIGHT...HOWEVER NOT EXPECTING IT TO BE TO DENSE. PLACED 5SM FOR
LATE TONIGHT. WINDS SHOULD SWITCH BACK TO SOUTH THIS EVENING AND
THEN TOMORROW TO NORTH. TLSJR
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 67 88 66 87 / 40 40 10 10
MKL 64 86 60 84 / 30 30 10 10
JBR 67 88 63 86 / 30 20 10 10
TUP 64 90 67 90 / 60 60 20 10
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
916 PM CDT MON JUN 11 2012
.UPDATE...CONVECTION IS DYING DOWN AS THE COLD FRONT NEARS MIDDLE
TENNESSEE. LATEST HRRR SHOWS ACTIVITY PRETTY MUCH DISSIPATING
COMPLETELY AFTER MIDNIGHT, ALTHOUGH WILL LEAVE IN REDUCED POP`S
OVERNIGHT GIVEN THE PROXIMITY OF THE FRONT AND THE EXISTING LOW-
LEVEL MOISTURE. HAVE ALSO ADJUSTED TOMORROW`S POP`S TO MORE OR
LESS LINE UP WITH THE OVERNIGHT GRIDS.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
ROSE
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
801 PM CDT MON JUN 11 2012
.DISCUSSION...
AVIATION DISCUSSION WAS UPDATED FOR 00Z TAFS.
&&
.PREV DISCUSSION... /ISSUED 711 PM CDT MON JUN 11 2012/
UPDATE...
UPDATED TO LOWER POPS ACROSS THE MID SOUTH FOR THIS EVENING AND
CLEAR SEVERE THUNDERSTORM WATCH #373 FOR THE ENTIRE AREA.
DISCUSSION...
THE SEVERE LINE OF THUNDERSTORMS THAT MOVES SOUTH ACROSS THE AREA
THIS AFTERNOON AND EVENING HAS NOW EXITED OUR AREA. STRATIFORM
RAIN BEHIND THE SEVERE CONVECTION WILL PERSIST FOR A FEW HOURS AT
MOST AND MAINTAINED LIKELY POPS OVER NORTH MISSISSIPPI TO ACCOUNT
FOR THIS. ELSEWHERE HAVE LOWERED POPS FOR THIS EVENING.
LATER TONIGHT...LATEST HIGH RESOLUTION RAPID REFRESH MODEL
INDICATES ADDITIONAL DEVELOPMENT OF CONVECTION OVER WESTERN
ARKANSAS ALONG STALLED OUTFLOW BOUNDARY. THIS CONVECTION MAY MOVE
BACK OVER SOUTHERN PORTIONS OF THE FORECAST AREA AFTER MIDNIGHT.
THE CURRENT FORECAST HAD ACCOUNTED FOR THIS ACTIVITY BUT
CONFIDENCE IS RATHER LOW. THE ATMOSPHERE MAY BE TOO WORKED OVER
FROM THIS EVENINGS CONVECTION OR NEW CONVECTION MAY BE ELEVATED
OVER THE DECAYING COLD POOL. LATER UPDATES MAY BE NEEDED AS THE
EVENTUAL EVOLUTION BECOMES MORE CLEAR.
UPDATED ZONES...GRIDS...AND HWO HAVE BEEN SENT.
JLH
PREV DISCUSSION... /ISSUED 320 PM CDT MON JUN 11 2012/
DISCUSSION...
A SEVERE FORWARD PROPAGATING MESOSCALE CONVECTIVE SYSTEM (MCS)
CURRENTLY ACROSS NORTHWEST TENNESSEE INTO EASTERN ARKANSAS WILL
CONTINUE TO RACE SOUTHEASTWARD THROUGH THE REMAINDER OF THE
AFTERNOON AND EVENING HOURS. THIS LINE HAS HAD A HISTORY OF WIND
DAMAGE AND THE PRE-CONVECTIVE ENVIRONMENT REMAIN FAVORABLE FOR
CONTINUED WIND DAMAGE WITH MLCAPES IN EXCESS OF 4000 J/KG. THIS
MCS CONTINUES TO MOVE ALONG THE NORTHEAST PERIPHERY OF STRONGER
CAPPING/EML OVER THE ARKLATEX REGION. THIS LINE OF SEVERE
THUNDERSTORMS SHOULD MOVE THROUGH THE REMAINDER OF THE FORECAST
AREA THROUGH THE EVENING.
LATER TONIGHT...THE FORECAST BECOMES MORE UNCERTAIN AS THE
ATMOSPHERE WILL INITIALLY BE WORKED OVER FROM THIS AFTERNOONS MCS.
THE CONVECTIVE OUTFLOW BOUNDARY SLOWS QUITE A BIT ACROSS NORTH-
CENTRAL ARKANSAS AND THIS AREA MAY BE PRIMED FOR REDEVELOPMENT
LATER THIS EVENING...WITH THE ATMOSPHERE POTENTIALLY RELOADING
ACROSS SOUTHWESTERN PORTIONS OF THE AREA. LATEST MODEL GUIDANCE
HINTS AT THIS OCCURENCE...BUT TIMING CONTINUES TO BE A PROBLEM AS
LATEST HRRR IS FASTER WITH MOST CONVECTION PRIOR TO 06Z AND ALL
OTHER MODEL GUIDANCE NOW SLOWER AND LINGERING CONVECTION THROUGH
THE NIGHT OVER THESE LOCATIONS. PLAN TO CARRY LIKELY POPS OVER THE
SOUTH AND WEST AFTER 06Z AND WILL MAINTAIN A SEVERE THREAT FOR
DAMAGING WINDS AND LARGE HAIL.
OVERNIGHT ACTIVITY SHOULD WANE LATE TONIGHT WITH SCATTERED
THUNDERSTORM REDEVELOPMENT POSSIBLE ALONG A SOUTHWARD MOVING COLD
FRONT ALONG THE I-40 CORRIDOR BY MID MORNING. THIS FRONT WILL
CONTINUE TO DROP SOUTH THROUGH EASTERN ARKANSAS AND NORTHERN
MISSISSIPPI BY AFTERNOON WITH THUNDERSTORM ACTIVITY BECOMING MORE
NUMEROUS IN COVERAGE. THE ATMOSPHERE WILL AGAIN DESTABILIZE OVER
THE SOUTHERN HALF OF THE AREA WITH STRONG TO POTENTIALLY SEVERE
STORMS AGAIN POSSIBLE.
THE COLD FRONT WILL MOVE THROUGH THE MID SOUTH BY TUESDAY NIGHT
WITH SURFACE HIGH PRESSURE BUILDING OVER THE AREA. THE FRONT
SHOULD STALL ACROSS CENTRAL MISSISSIPPI AS UPPER LEVEL HEIGHTS
RISE. DRY AND VERY WARM WEATHER CAN BE EXPECTED WEDNESDAY THROUGH
FRIDAY MORNING. THE FRONT WILL RETURN BACK TO THE NORTH AS A WARM
FRONT BY FRIDAY ALLOWING FOR A DEEP TROPICAL MOISTURE TO ADVANCE
BACK INTO THE MID SOUTH. ISOLATED SHOWERS AND THUNDERSTORMS WILL
AGAIN BE POSSIBLE DURING PEAK HEATING ON BOTH FRIDAY AND SATURDAY.
A DRIER AIRMASS WILL WORK INTO THE AREA BY SUNDAY HELPING TO LIMIT
DIURNAL CONVECTION. TEMPERATURES WILL REMAIN SEASONALLY WARM WITH
INCREASING HUMIDITY LEVELS THROUGH THE END OF THE EXTENDED
FORECAST PERIOD.
JLH
&&
.AVIATION...
00Z TAFS
SQUALL TO SOUTH OF AREA. SOME STRATIFORM RAIN BEHIND SYSTEM WILL
LINGER FOR A COUPLE HOURS IN MOST AREAS. SOME MIST/FOG MAY DEVELOP
TONIGHT...HOWEVER NOT EXPECTING IT TO BE TO DENSE. PLACED 5SM FOR
LATE TONIGHT. WINDS SHOULD SWITCH BACK TO SOUTH THIS EVENING AND
THEN TOMORROW TO NORTH. TLSJR
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 69 88 66 87 / 50 40 10 10
MKL 69 86 60 84 / 40 30 10 10
JBR 69 88 63 86 / 40 20 10 10
TUP 67 90 67 90 / 60 60 20 10
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
711 PM CDT MON JUN 11 2012
.UPDATE...
UPDATED TO LOWER POPS ACROSS THE MID SOUTH FOR THIS EVENING AND
CLEAR SEVERE THUNDERSTORM WATCH #373 FOR THE ENTIRE AREA.
&&
.DISCUSSION...
THE SEVERE LINE OF THUNDERSTORMS THAT MOVES SOUTH ACROSS THE AREA
THIS AFTERNOON AND EVENING HAS NOW EXITED OUR AREA. STRATIFORM
RAIN BEHIND THE SEVERE CONVECTION WILL PERSIST FOR A FEW HOURS AT
MOST AND MAINTAINED LIKELY POPS OVER NORTH MISSISSIPPI TO ACCOUNT
FOR THIS. ELSEWHERE HAVE LOWERED POPS FOR THIS EVENING.
LATER TONIGHT...LATEST HIGH RESOLUTION RAPID REFRESH MODEL
INDICATES ADDITIONAL DEVELOPMENT OF CONVECTION OVER WESTERN
ARKANSAS ALONG STALLED OUTFLOW BOUNDARY. THIS CONVECTION MAY MOVE
BACK OVER SOUTHERN PORTIONS OF THE FORECAST AREA AFTER MIDNIGHT.
THE CURRENT FORECAST HAD ACCOUNTED FOR THIS ACTIVITY BUT
CONFIDENCE IS RATHER LOW. THE ATMOSPHERE MAY BE TOO WORKED OVER
FROM THIS EVENINGS CONVECTION OR NEW CONVECTION MAY BE ELEVATED
OVER THE DECAYING COLD POOL. LATER UPDATES MAY BE NEEDED AS THE
EVENTUAL EVOLUTION BECOMES MORE CLEAR.
UPDATED ZONES...GRIDS...AND HWO HAVE BEEN SENT.
JLH
&&
.PREV DISCUSSION... /ISSUED 320 PM CDT MON JUN 11 2012/
DISCUSSION...
A SEVERE FORWARD PROPAGATING MESOSCALE CONVECTIVE SYSTEM (MCS)
CURRENTLY ACROSS NORTHWEST TENNESSEE INTO EASTERN ARKANSAS WILL
CONTINUE TO RACE SOUTHEASTWARD THROUGH THE REMAINDER OF THE
AFTERNOON AND EVENING HOURS. THIS LINE HAS HAD A HISTORY OF WIND
DAMAGE AND THE PRE-CONVECTIVE ENVIRONMENT REMAIN FAVORABLE FOR
CONTINUED WIND DAMAGE WITH MLCAPES IN EXCESS OF 4000 J/KG. THIS
MCS CONTINUES TO MOVE ALONG THE NORTHEAST PERIPHERY OF STRONGER
CAPPING/EML OVER THE ARKLATEX REGION. THIS LINE OF SEVERE
THUNDERSTORMS SHOULD MOVE THROUGH THE REMAINDER OF THE FORECAST
AREA THROUGH THE EVENING.
LATER TONIGHT...THE FORECAST BECOMES MORE UNCERTAIN AS THE
ATMOSPHERE WILL INITIALLY BE WORKED OVER FROM THIS AFTERNOONS MCS.
THE CONVECTIVE OUTFLOW BOUNDARY SLOWS QUITE A BIT ACROSS NORTH-
CENTRAL ARKANSAS AND THIS AREA MAY BE PRIMED FOR REDEVELOPMENT
LATER THIS EVENING...WITH THE ATMOSPHERE POTENTIALLY RELOADING
ACROSS SOUTHWESTERN PORTIONS OF THE AREA. LATEST MODEL GUIDANCE
HINTS AT THIS OCCURENCE...BUT TIMING CONTINUES TO BE A PROBLEM AS
LATEST HRRR IS FASTER WITH MOST CONVECTION PRIOR TO 06Z AND ALL
OTHER MODEL GUIDANCE NOW SLOWER AND LINGERING CONVECTION THROUGH
THE NIGHT OVER THESE LOCATIONS. PLAN TO CARRY LIKELY POPS OVER THE
SOUTH AND WEST AFTER 06Z AND WILL MAINTAIN A SEVERE THREAT FOR
DAMAGING WINDS AND LARGE HAIL.
OVERNIGHT ACTIVITY SHOULD WANE LATE TONIGHT WITH SCATTERED
THUNDERSTORM REDEVELOPMENT POSSIBLE ALONG A SOUTHWARD MOVING COLD
FRONT ALONG THE I-40 CORRIDOR BY MID MORNING. THIS FRONT WILL
CONTINUE TO DROP SOUTH THROUGH EASTERN ARKANSAS AND NORTHERN
MISSISSIPPI BY AFTERNOON WITH THUNDERSTORM ACTIVITY BECOMING MORE
NUMEROUS IN COVERAGE. THE ATMOSPHERE WILL AGAIN DESTABILIZE OVER
THE SOUTHERN HALF OF THE AREA WITH STRONG TO POTENTIALLY SEVERE
STORMS AGAIN POSSIBLE.
THE COLD FRONT WILL MOVE THROUGH THE MID SOUTH BY TUESDAY NIGHT
WITH SURFACE HIGH PRESSURE BUILDING OVER THE AREA. THE FRONT
SHOULD STALL ACROSS CENTRAL MISSISSIPPI AS UPPER LEVEL HEIGHTS
RISE. DRY AND VERY WARM WEATHER CAN BE EXPECTED WEDNESDAY THROUGH
FRIDAY MORNING. THE FRONT WILL RETURN BACK TO THE NORTH AS A WARM
FRONT BY FRIDAY ALLOWING FOR A DEEP TROPICAL MOISTURE TO ADVANCE
BACK INTO THE MID SOUTH. ISOLATED SHOWERS AND THUNDERSTORMS WILL
AGAIN BE POSSIBLE DURING PEAK HEATING ON BOTH FRIDAY AND SATURDAY.
A DRIER AIRMASS WILL WORK INTO THE AREA BY SUNDAY HELPING TO LIMIT
DIURNAL CONVECTION. TEMPERATURES WILL REMAIN SEASONALLY WARM WITH
INCREASING HUMIDITY LEVELS THROUGH THE END OF THE EXTENDED
FORECAST PERIOD.
JLH
&&
.AVIATION...
18Z TAF SET
CONVECTIVE COMPLEX IS SET TO SWEEP THROUGH THE MIDSOUTH THIS
AFTERNOON AND EARLY THIS EVENING. THIS IS CORROBORATED WELL BY THE
LATEST HRRR RUN. HAVE TIMED TEMPO GROUPS AT ALL SITES. EXPECT A
FEW QUIET HOURS AFTER THE PASSAGE OF THE FIRST ROUND OF TSRAS.
EXPECT REDEVELOPMENT TO OCCUR OVERNIGHT AS THE FRONT MOVES INTO
THE REGION. KEPT A VCTS GOING FOR NOW SINCE IT IS DIFFICULT TO
TIME THIS MESOSCALE ACTIVITY BEYOND A FEW HOURS. EXPECT SSW WINDS
AT 8-10 KTS THIS AFTERNOON. AS THE COMPLEX MOVES THROUGH WINDS
SHOULD SHARPLY SHIFT TO THE NORTH AND GUST. ADDED A WIND GROUP TO
KJBR IN ANTICIPATION OF THIS. NOT CONFIDENT ENOUGH AT THE OTHER
3 SITES TO ADD THIS YET. EXPECT WINDS TO BACK AFTER THE COMPLEX
MOVES THROUGH AND THEN EVENTUALLY RETURN TO LIGHT SOUTHERLY
OVERNIGHT. THE FRONT WILL PASS THROUGH EARLY TUESDAY AND WINDS
WILL SHIFT TO THE NORTH AT 8-10 KTS.
SJM
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 69 88 66 87 / 50 40 10 10
MKL 69 86 60 84 / 40 30 10 10
JBR 69 88 63 86 / 40 20 10 10
TUP 67 90 67 90 / 60 60 20 10
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
1246 PM CDT SUN JUN 10 2012
.UPDATE...FOR 18Z AVIATION DISCUSSION.
&&
.AVIATION...18Z AVIATION DISCUSSION.
UNCERTAINTIES...FLUCTUATIONS BETWEEN VFR TO MVFR TO POSSIBLE IFR
CEILINGS/ONSET OF MAIN SWATH OF SHWRS/TSTMS WITH UPPER LEVEL LOW/
TROUGH PASSAGE. WILL CONTINUE WITH PREDOMINATE MVFR CEILINGS...BUT
TEMP FLUCTUATIONS TO VFR/IFR CEILINGS POSSIBLE. EXPECT MAIN SWATH
OF SHWRS...WITH SCT TSTMS...ASSOCIATED WITH UPPER LEVEL LOW/UPPER
LEVEL TROUGH MOVEMENT NEWD OUT OF WRN GULF BETWEEN 11/03Z-11/15Z...
ESPECIALLY CSV. CEILINGS SHOULD BECOME PREDOMINATELY IFR BETWEEN
11/09Z-11/14Z ALSO. SOME DRIER AIR MIGHT TRY TO WORK ACROSS WRN TAF
SITES AFTER 11/14Z...BUT ANY BREAKS IN CLOUD COVERAGE WITH DIURNAL
INFLUENCES KICKING IN SHOULD RESULT IN TSTMS DEVELOPING NEAR TAF
SITES DURING THIS TIME PERIOD ALSO.
&&
.PREV DISCUSSION.../ISSUED 1113 AM CDT SUN JUN 10 2012/
UPDATE...
LEAD WAVE THAT BROUGHT LIGHT MORNING RAINFALL WAS WEAKENING IN
DRIER AIR NORTH. CONSIDERABLE CLOUDINESS WL REMAIN ACROSS THE
REGION WITH LIMITED AFTN HEATING. MARGINAL INSTAB EXPECTED TO
DRIVE SCT SHOWERS AND A FEW THUNDERSTORMS THIS AFTN.
PREV DISCUSSION.../ISSUED 658 AM CDT SUN JUN 10 2012/
UPDATE...FOR 12Z AVIATION FORECAST
AVIATION...
LATEST RUC HAS UPPER LOW CENTERED OVER SOUTHERN ARKANSAS WITH
WATER VAPOR IMAGERY SHOWING PLENTY OF MOISTURE ACROSS LOWER
MISSISSIPPI AND TENNESSEE VALLEYS. GOOD MOISTURE TRANSPORT AND LOW
LEVEL CONVERGENCE INTO MID STATE FROM ALABAMA THIS MORNING AND IT
WILL CONTINUE THROUGHOUT THE DAY AND INTO THE EVENING.
INITIAL RAIN BAND NOW WORKING NORTH THROUGH THE TENNESSEE VALLEY
ASSOCIATED WITH DEFORMATION FIELD. HRRR WORKS THIS INITIAL BAND INTO
KENTUCKY WITH SCATTERED CONVECTION DEVELOPING IN BEHIND IT ACROSS
MIDDLE TENNESSEE. EXPECT CONVECTION TO INCREASE IN NUMBER DURING
THE AFTERNOON HOURS AND BECOME MORE INTENSE. TRIED TO FOLLOW THIS
SCENARIO IN FORECAST FOR TERMINALS. ALSO LOOK FOR THE CEILINGS TO
LOWER INTO MVFR CATEGORY AT TIMES AS LOWER TROPOSPHERE APPROACHES
SATURATION. EXPECT THERE WILL SOME THUNDERSTORM ACTIVITY AROUND
DURING THE AFTERNOON AND INTO THE EVENING. SHORT RANGE MODELS
DEVELOP STORMS AFTER 20Z.
BOYD
PREV DISCUSSION.../ISSUED 341 AM CDT SUN JUN 10 2012/
DISCUSSION...
THE WEEK AT A GLANCE SUMMARY...THERE IS A GOOD CHANCE OF RAIN
TODAY THROUGH TUESDAY THEN GENERALLY DRY AND A LITTLE WARMER THE
REST OF THE WEEK.
UPPER LEVEL LOW PRESSURE OVER THE LOWER MS VALLEY WILL MOVE
NORTHEAST TODAY AND TONIGHT. THIS PATTERN ESTABLISHES A DEEP
SOUTHEASTERLY FLOW ACROSS THE REGION TODAY WITH A SIGNIFICANT
INCREASE IN MOISTURE. MODELS CONTINUE SHOWING PW/S HEADING TO NEAR
2 INCHES BY THIS AFTERNOON. VERY LIGHT RETURNS WERE SEEN ON RADAR
EARLY THIS MORNING...AND GENERAL LIFT AHEAD OF THE LOW WILL BE
ENOUGH TO WARRANT POPS IN THE LIKELY CATEGORY TODAY. SHOWERS WILL
BE MORE COMMON THAN THUNDERSTORMS AS INSTABILITY LOOKS PRETTY
MEAGER EXCEPT FOR SW PART OF MIDDLE TN. EXPECT RAINFALL TO AVERAGE
1/2 INCH OR LESS AREA WIDE TODAY/TONIGHT.
DESPITE THE DEPARTURE OF THE UPPER LOW ON MONDAY...RAIN CHANCES
WILL CONTINUE MONDAY...MONDAY NIGHT AND INTO TUESDAY AS A WEAK
COLD FRONT APPROACHES. IN FACT THERE MAY BE A FEW STRONGER STORMS
MONDAY AFTN/EVE BASED ON EXPECTED INCREASE IN INSTABILITY. CHANCE
FOR STORMS WILL DECREASE FOR MUCH OF THE AREA DURING THE DAY ON
TUESDAY ONCE THE FRONT PASSES...BUT CHANCES MAY LINGER ALL DAY ON
THE PLATEAU. ADDITIONAL RAINFALL AMOUNTS DURING THIS 36 HOUR
PERIOD COULD BE AROUND ANOTHER 1/2 INCH EXCEPT GREATER IN THE
STRONGER STORMS.
THE REST OF THE WEEK WILL FEATURE A RETURN TO TYPICAL EARLY SUMMER
WEATHER AS A WEAK HIGH PRESSURE RIDGE SETTLES IN OVER THE MS/OH/TN
VALLEYS. DAYTIME TEMPS WILL APPROACH 90 AGAIN BUT MOST AREAS WILL
BE DRY. THERE MAY BE AN ISOLATED AFTERNOON STORM OR TWO ON THE
PLATEAU EACH DAY BUT VERY LOW CONFIDENCE/POPS SO WILL LEAVE OUT OF
FORECAST FOR NOW.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
31
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1113 AM CDT SUN JUN 10 2012
.UPDATE...
LEAD WAVE THAT BROUGHT LIGHT MORNING RAINFALL WAS WEAKENING IN
DRIER AIR NORTH. CONSIDERABLE CLOUDINESS WL REMAIN ACROSS THE
REGION WITH LIMITED AFTN HEATING. MARGINAL INSTAB EXPECTED TO
DRIVE SCT SHOWERS AND A FEW THUNDERSTORMS THIS AFTN.
&&
.PREV DISCUSSION... /ISSUED 658 AM CDT SUN JUN 10 2012/
UPDATE...FOR 12Z AVIATION FORECAST
AVIATION...
LATEST RUC HAS UPPER LOW CENTERED OVER SOUTHERN ARKANSAS WITH
WATER VAPOR IMAGERY SHOWING PLENTY OF MOISTURE ACROSS LOWER
MISSISSIPPI AND TENNESSEE VALLEYS. GOOD MOISTURE TRANSPORT AND LOW
LEVEL CONVERGENCE INTO MID STATE FROM ALABAMA THIS MORNING AND IT
WILL CONTINUE THROUGHOUT THE DAY AND INTO THE EVENING.
INITIAL RAIN BAND NOW WORKING NORTH THROUGH THE TENNESSEE VALLEY
ASSOCIATED WITH DEFORMATION FIELD. HRRR WORKS THIS INITIAL BAND INTO
KENTUCKY WITH SCATTERED CONVECTION DEVELOPING IN BEHIND IT ACROSS
MIDDLE TENNESSEE. EXPECT CONVECTION TO INCREASE IN NUMBER DURING
THE AFTERNOON HOURS AND BECOME MORE INTENSE. TRIED TO FOLLOW THIS
SCENARIO IN FORECAST FOR TERMINALS. ALSO LOOK FOR THE CEILINGS TO
LOWER INTO MVFR CATEGORY AT TIMES AS LOWER TROPOSPHERE APPROACHES
SATURATION. EXPECT THERE WILL SOME THUNDERSTORM ACTIVITY AROUND
DURING THE AFTERNOON AND INTO THE EVENING. SHORT RANGE MODELS
DEVELOP STORMS AFTER 20Z.
BOYD
PREV DISCUSSION... /ISSUED 341 AM CDT SUN JUN 10 2012/
DISCUSSION...
THE WEEK AT A GLANCE SUMMARY...THERE IS A GOOD CHANCE OF RAIN
TODAY THROUGH TUESDAY THEN GENERALLY DRY AND A LITTLE WARMER THE
REST OF THE WEEK.
UPPER LEVEL LOW PRESSURE OVER THE LOWER MS VALLEY WILL MOVE
NORTHEAST TODAY AND TONIGHT. THIS PATTERN ESTABLISHES A DEEP
SOUTHEASTERLY FLOW ACROSS THE REGION TODAY WITH A SIGNIFICANT
INCREASE IN MOISTURE. MODELS CONTINUE SHOWING PW/S HEADING TO NEAR
2 INCHES BY THIS AFTERNOON. VERY LIGHT RETURNS WERE SEEN ON RADAR
EARLY THIS MORNING...AND GENERAL LIFT AHEAD OF THE LOW WILL BE
ENOUGH TO WARRANT POPS IN THE LIKELY CATEGORY TODAY. SHOWERS WILL
BE MORE COMMON THAN THUNDERSTORMS AS INSTABILITY LOOKS PRETTY
MEAGER EXCEPT FOR SW PART OF MIDDLE TN. EXPECT RAINFALL TO AVERAGE
1/2 INCH OR LESS AREA WIDE TODAY/TONIGHT.
DESPITE THE DEPARTURE OF THE UPPER LOW ON MONDAY...RAIN CHANCES
WILL CONTINUE MONDAY...MONDAY NIGHT AND INTO TUESDAY AS A WEAK
COLD FRONT APPROACHES. IN FACT THERE MAY BE A FEW STRONGER STORMS
MONDAY AFTN/EVE BASED ON EXPECTED INCREASE IN INSTABILITY. CHANCE
FOR STORMS WILL DECREASE FOR MUCH OF THE AREA DURING THE DAY ON
TUESDAY ONCE THE FRONT PASSES...BUT CHANCES MAY LINGER ALL DAY ON
THE PLATEAU. ADDITIONAL RAINFALL AMOUNTS DURING THIS 36 HOUR
PERIOD COULD BE AROUND ANOTHER 1/2 INCH EXCEPT GREATER IN THE
STRONGER STORMS.
THE REST OF THE WEEK WILL FEATURE A RETURN TO TYPICAL EARLY SUMMER
WEATHER AS A WEAK HIGH PRESSURE RIDGE SETTLES IN OVER THE MS/OH/TN
VALLEYS. DAYTIME TEMPS WILL APPROACH 90 AGAIN BUT MOST AREAS WILL
BE DRY. THERE MAY BE AN ISOLATED AFTERNOON STORM OR TWO ON THE
PLATEAU EACH DAY BUT VERY LOW CONFIDENCE/POPS SO WILL LEAVE OUT OF
FORECAST FOR NOW.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
04
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
658 AM CDT SUN JUN 10 2012
.UPDATE...FOR 12Z AVIATION FORECAST
&&
.AVIATION...
LATEST RUC HAS UPPER LOW CENTERED OVER SOUTHERN ARKANSAS WITH
WATER VAPOR IMAGERY SHOWING PLENTY OF MOISTURE ACROSS LOWER
MISSISSIPPI AND TENNESSEE VALLEYS. GOOD MOISTURE TRANSPORT AND LOW
LEVEL CONVERGENCE INTO MID STATE FROM ALABAMA THIS MORNING AND IT
WILL CONTINUE THROUGHOUT THE DAY AND INTO THE EVENING.
INITIAL RAIN BAND NOW WORKING NORTH THROUGH THE TENNESSEE VALLEY
ASSOCIATED WITH DEFORMATION FIELD. HRRR WORKS THIS INITIAL BAND INTO
KENTUCKY WITH SCATTERED CONVECTION DEVELOPING IN BEHIND IT ACROSS
MIDDLE TENNESSEE. EXPECT CONVECTION TO INCREASE IN NUMBER DURING
THE AFTERNOON HOURS AND BECOME MORE INTENSE. TRIED TO FOLLOW THIS
SCENARIO IN FORECAST FOR TERMINALS. ALSO LOOK FOR THE CEILINGS TO
LOWER INTO MVFR CATEGORY AT TIMES AS LOWER TROPOSPHERE APPROACHES
SATURATION. EXPECT THERE WILL SOME THUNDERSTORM ACTIVITY AROUND
DURING THE AFTERNOON AND INTO THE EVENING. SHORT RANGE MODELS
DEVELOP STORMS AFTER 20Z.
BOYD
&&
.PREV DISCUSSION... /ISSUED 341 AM CDT SUN JUN 10 2012/
DISCUSSION...
THE WEEK AT A GLANCE SUMMARY...THERE IS A GOOD CHANCE OF RAIN
TODAY THROUGH TUESDAY THEN GENERALLY DRY AND A LITTLE WARMER THE
REST OF THE WEEK.
UPPER LEVEL LOW PRESSURE OVER THE LOWER MS VALLEY WILL MOVE
NORTHEAST TODAY AND TONIGHT. THIS PATTERN ESTABLISHES A DEEP
SOUTHEASTERLY FLOW ACROSS THE REGION TODAY WITH A SIGNIFICANT
INCREASE IN MOISTURE. MODELS CONTINUE SHOWING PW/S HEADING TO NEAR
2 INCHES BY THIS AFTERNOON. VERY LIGHT RETURNS WERE SEEN ON RADAR
EARLY THIS MORNING...AND GENERAL LIFT AHEAD OF THE LOW WILL BE
ENOUGH TO WARRANT POPS IN THE LIKELY CATEGORY TODAY. SHOWERS WILL
BE MORE COMMON THAN THUNDERSTORMS AS INSTABILITY LOOKS PRETTY
MEAGER EXCEPT FOR SW PART OF MIDDLE TN. EXPECT RAINFALL TO AVERAGE
1/2 INCH OR LESS AREA WIDE TODAY/TONIGHT.
DESPITE THE DEPARTURE OF THE UPPER LOW ON MONDAY...RAIN CHANCES
WILL CONTINUE MONDAY...MONDAY NIGHT AND INTO TUESDAY AS A WEAK
COLD FRONT APPROACHES. IN FACT THERE MAY BE A FEW STRONGER STORMS
MONDAY AFTN/EVE BASED ON EXPECTED INCREASE IN INSTABILITY. CHANCE
FOR STORMS WILL DECREASE FOR MUCH OF THE AREA DURING THE DAY ON
TUESDAY ONCE THE FRONT PASSES...BUT CHANCES MAY LINGER ALL DAY ON
THE PLATEAU. ADDITIONAL RAINFALL AMOUNTS DURING THIS 36 HOUR
PERIOD COULD BE AROUND ANOTHER 1/2 INCH EXCEPT GREATER IN THE
STRONGER STORMS.
THE REST OF THE WEEK WILL FEATURE A RETURN TO TYPICAL EARLY SUMMER
WEATHER AS A WEAK HIGH PRESSURE RIDGE SETTLES IN OVER THE MS/OH/TN
VALLEYS. DAYTIME TEMPS WILL APPROACH 90 AGAIN BUT MOST AREAS WILL
BE DRY. THERE MAY BE AN ISOLATED AFTERNOON STORM OR TWO ON THE
PLATEAU EACH DAY BUT VERY LOW CONFIDENCE/POPS SO WILL LEAVE OUT OF
FORECAST FOR NOW.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
01
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
1012 PM CDT MON JUN 11 2012
.UPDATE...
CONVECTION SO FAR THIS EVENING HAS REMAINED REMOVED FROM THE CWA.
STORMS ASSOCIATED WITH THE FRONTAL BOUNDARY TO OUR SOUTH HAVE
SKIRTED AROUND THE SOUTHEAST EDGE OF THE FA THROUGH THE EVENING
HOURS UP TO THIS POINT. OUTFLOW FROM EARLIER ACTIVITY WAS IN CLOSE
PROXIMITY TO THE SOUTHERN ROLLING PLAINS AND COULD YET BE THE
FOCUS FOR STORM DEVELOPMENT THROUGH THE LATE EVENING HOURS.
ELSEWHERE...CONVECTION BETWEEN NOW AND MIDNIGHT DOES NOT SEEM AS
LIKELY AND HAVE DROPPED POPS GENERALLY TO AOB 20 PERCENT. AFTER
MIDNIGHT...INCREASINGLY MOIST/UNSTABLE EASTERLY LOW-LEVEL
FLOW...COUPLED WITH FAVORABLE UPPER JET DYNAMICS...AND A WEAK
UPPER DISTURBANCE COULD YET BE ENOUGH TO FORCE SOME LATE NIGHT
ELEVATED STORMS...IF WARM MID-LEVELS /CIN/ CAN BE OVERCOME. NOT
CERTAIN OF THIS SCENARIO...BUT THE 00Z NAM DOES CONTINUE TO
ADVERTISE A COMPLEX OF STORMS DEVELOPING ACROSS THE TEXAS
PANHANDLE AND ROLLING ACROSS THE NORTHEAST ZONES THROUGH EARLY
TUESDAY MORNING. THE 23Z HRRR DOES ALSO INDICATE THAT THE RATHER
ISOLATED CONVECTION IN NE NM WILL GROW UPSCALE LATE TONIGHT AND
MOVE ACROSS THE NORTHERN ZONES LATE TONIGHT. GIVEN THIS...HAVE
MAINTAINED CHANCE POPS OVER ROUGHLY THE NORTHEAST HALF OF THE FA
AFTER 06Z. GIVEN MODERATE INSTABILITY AND SUFFICIENT SHEAR...A FEW
ELEVATED STRONG TO SEVERE STORMS COULD BE POSSIBLE. UPDATED
FORECAST PRODUCTS HAVE BEEN SENT.
&&
.PREV DISCUSSION... /ISSUED 653 PM CDT MON JUN 11 2012/
AVIATION...
VFR CONDITIONS LOOK TO PREVAIL NEXT 24 HOURS WITH PERHAPS A CAVEAT
OR TWO. THUNDERSTORM CHANCES LOOK QUITE MEAGER THIS EVENING AND
HAVE DROPPED MENTION OF TSRA. MODELS HAVE BEEN HINTING AT AN MCS
MOVING OUT OF NEW MEXICO FOR A COUPLE DAYS DURING THE OVERNIGHT
HOURS. IF THIS ACTUALLY PLAYS OUT...KCDS LOOKS TO HAVE MOST LIKELY
SHOT AT GETTING STORMS BUT CONFIDENCE REMAINS TOO LOW TO INCLUDE
ATTM. AS MOIST AIR ADVECTION CONTINUES NEAR KCDS...WE COULD SEE
SOME LOW CLOUDS OR PERHAPS EVEN SOME LIGHT FOG DEVELOP THERE
TOWARD MORNING. INTO THE AFTERNOON HOURS ON TUESDAY...STORM
CHANCES WILL ONCE AGAIN INCREASE.
PREV DISCUSSION... /ISSUED 332 PM CDT MON JUN 11 2012/
SHORT TERM...
POTENTIALLY WET PATTERN DEVELOPING OVER THE NEXT 36 HOURS. SFC
ANALYSIS THIS AFTERNOON SHOWS A COLD FRONT THAT HAS JUST ABOUT
STALLED NEAR A HOBBS TO SWEETWATER TO WICHITA FALLS LINE. SOME
MOISTURE POOLING IS EVIDENT EITHER SIDE OF THE BOUNDARY. NORTH OF
THE FRONT UPSLOPE FLOW DEVELOPING ACROSS ERN NM AS WINDS SLOWLY VEER
TOWARD THE EAST. LOOKING AT TWO POTENTIAL AREAS OF THUNDERSTORM
DEVELOPMENT LATE THIS AFTERNOON OR EARLY THIS EVENING SHOULD CAPPING
INVERSION BE BREACHED...ONE BEING THE VCNTY OF THE COLD FRONT THAT
COULD SEE SOME STORMS MOVE INTO THE SERN ZONES AND THE SECOND BEING
THE HIGH TERRAIN JUST WEST OF THE FCST AREA WHERE MODESTLY MOIST
UPSLOPE FLOW MAY BE ENOUGH TO INITIATE ISO TO SCT THUNDER THERE WITH
A POTENTIAL TO MOVE INTO THE WRN ZONES DURING THE EVENING. MOVING
INTO THE OVERNIGHT HOURS AND EARLY TUESDAY BEGINS TO BREED MIXED
SIGNALS AS THE 12Z NAM AND THE 12Z TTU-WRF BOTH DEVELOP
THUNDERSTORMS ACROSS THE SRN PANHANDLE. GFS NOT SHOWING SIMILAR QPF
BUT IS SHOWING SIMILAR SUPPORT ONCE BEGIN TO LOOK AT MID LEVELS.
MODELS ARE PRETTY CONSISTING SHOWING MID LEVEL MOISTENING AS LARGE
MOISTURE PLUME EVIDENT ON WATER VAPOR IMAGERY SPREADS ACROSS THE
REGION. PROGGED SOUNDINGS SHOWING ABOUT 1500 J/KG OF CAPE LATE
TONIGHT WHEN LIFTING FROM ABOUT 750 MB BUT ALSO SHOWING ABOUT 100
J/KG OF CIN. HOWEVER...LIFT FROM MODEST MID LEVEL MOIST ISENTROPIC
MECHANISM AND PAIR OF JET STREAKS /ONE ACROSS CNTL PLAINS AND THE
OTHER ACROSS THE SRN ROCKIES/ MAY BE ENOUGH TO OVERCOME THE NEGATIVE
ENERGY WITH SCATTERED TSRA LOOKING POSSIBLE. WILL GO AHEAD AND FOCUS
ON THAT AREA WITH HIGHER CHANCE POPS AFTER 06Z WHILE PRE-06Z PERIOD
WILL FOCUS ON THE AFOREMENTIONED WRN AND SERN AREAS.
WHETHER THE SRN PANHANDLE CONVECTION CAN DEVELOP LATE TONIGHT AND
THEN BE SUSTAINED INTO THE 12Z-18Z PERIOD AS THE NAM SUGGEST WILL BE
KEY IN CONVECTIVE FCST FOR TUESDAY AFTN. OBVIOUSLY WIDESPREAD
CONVECTION DURING THE MORNING HOURS WOULD INITIALLY WEAKEN CHANCES
FOR PRECIP DURING PEAK CONVECTIVE HOURS TUESDAY AFTN ACROSS THE
ROLLING PLAINS. HOWEVER...FOCUS FOR INITIATION LOOKS LIKE IT MAY BE
FARTHER WEST IN A ZONE OF GENERALLY NW-SE ORIENTED MOISTURE
ADVECTION AS THE COLD FRONT LIFTS NWD TUESDAY AFTN. FCST HIGH
TEMPERATURES WILL BE COOLER...GENERALLY IN THE 80S...BUT RICH LOW
LEVEL MOISTURE SHOULD STILL MAKE FOR MLCAPE IN EXCESS OF 1500 J/KG
IN MUCH OF THE FCST AREA AND POSSIBLY APPROACHING 2500-PLUS IN A
BAND NEAR THE RETREATING FRONT. WILL CONTINUE WITH CHC POPS FOR NOW
RUNNING THE HIGHEST CHANCE ACROSS ROUGHLY THE WRN HALF OF THE AREA
WITH UNDERSTANDING THAT A RELATIVE MINIMUM ACROSS THE EAST MAY NOT
WORK OUT IF AFOREMENTIONED OVERNIGHT CONVECTION DOES NOT
MATERIALIZE. WILL THEN CONTINUE WITH HIGH CHANCE POPS TUESDAY AS
CONVECTION SPREADS EWD DURING THE EVENING AND THEN POTENTIAL FOR AN
MCS INTO THE NRN ZONES LATE IN THE NIGHT ROLLING IN FROM THE NW.
LONG TERM...
BY WEDNESDAY THE FRONTAL SYSTEM IS EXPECTED TO LIFT NORTHWARD AND
AREA RAIN CHANCES SHOULD BEGIN TO DECREASE. UPPER LEVEL MOISTURE
STREAMING OUT OF THE PACIFIC ACROSS MEXICO INTO THE AREA IS ONE
POSITIVE FACTOR. THE DRYLINE SHOULD REMAIN TO OUR WEST OVER NEW
MEXICO FOR MOST OF THE REMAINDER OF THE WEEK THROUGH NEXT WEEKEND.
THE SLIGHT CHANCE OF THUNDERSTORMS WHICH REMAINS IN THE FORECAST
THROUGH NEXT WEEKEND IS MOSTLY TIED TO DRYLINE ACTIVITY BEING PUSHED
EASTWARD WITH WESTERLY WINDS ALOFT IN THE LATE AFTERNOON AND EVENING
HOURS. BEST RAIN CHANCES WILL BE OVER OUR WESTERN COUNTIES.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 60 81 63 87 64 / 20 40 40 30 30
TULIA 62 80 64 87 64 / 40 40 50 30 20
PLAINVIEW 63 80 65 88 65 / 30 40 40 30 20
LEVELLAND 64 86 65 91 67 / 20 40 50 30 20
LUBBOCK 65 84 66 90 68 / 30 40 50 30 20
DENVER CITY 65 91 65 92 68 / 20 40 40 30 30
BROWNFIELD 66 90 68 91 68 / 20 40 50 30 20
CHILDRESS 66 85 67 88 68 / 40 50 50 20 20
SPUR 68 85 68 90 68 / 30 40 50 20 20
ASPERMONT 70 89 70 92 71 / 30 40 50 20 20
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
26/23
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1227 PM CDT SUN JUN 10 2012
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
257 AM CDT SUN JUN 10 2012
MAIN FORECAST CONCERN IS ON PRECIPITATION CHANCES TONIGHT INTO
MONDAY...ALONG WITH ANY SEVERE RISK THIS EVENING.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED TROUGHING OVER THE NORTHERN ROCKIES AND RIDGING OVER THE
WESTERN GREAT LAKES REGION. SUBSIDENCE AND PLENTY OF DRY AIR
UNDERNEATH THE UPPER RIDGING...NOTED BY PRECIPITABLE WATER VALUES
FROM 00Z SOUNDINGS AT MPX AND DVN NEAR 0.7 INCHES...HAS CONTINUED TO
KEEP SKIES CLEAR. A 30-40 KT SOUTHWEST WIND AT 850MB PER PROFILER
DATA STILL EXISTS FROM EASTERN KANSAS INTO THE FORECAST AREA...WHICH
HAS HELPED TO MAINTAIN TEMPERATURES AROUND 18C PER 00Z SOUNDINGS AND
RAP ANALYSIS. THE LOW LEVEL JET TOO IS ALSO HELPING TO BRING
SLIGHTLY MORE MOISTURE NORTHEASTWARD...WITH 1 INCH PRECIPITABLE
WATER VALUES NOW ENTERING FAR SOUTHERN IOWA AS SEEN ON GOES SOUNDER
IMAGERY. HIGHER MOISTURE IS PRESENT OVER THE DAKOTAS...WHERE THE
COMBINATION OF A SLIGHTLY STRONGER LOW LEVEL JET IS IMPINGING ON
DPVA DOWNSTREAM OF THE NORTHERN ROCKIES TROUGH...LEADING TO
CONVECTIVE DEVELOPMENT. RAP ANALYSIS INDICATING PRECIPITABLE WATER
VALUES THERE NEAR 1.5 INCHES. MUCH OF THE CONVECTION LIES BEHIND A
COLD FRONT...STRETCHING FROM JUST WEST OF FARGO DOWN INTO SOUTHWEST
NEBRASKA WHERE A 987MB LOW IS PRESENT.
TODAY...THE NORTHERN ROCKIES TROUGH IS PROGGED BY ALL MODELS TO LIFT
TO THE NORTHEAST...INDUCED PARTLY BY A POTENT SHORTWAVE AT THE BASE
OF THE TROUGH LIFTING NORTHEAST. BY 00Z MONDAY...THE CORE IS
FORECAST TO BE SITUATED FROM SASKATCHEWAN INTO THE WESTERN DAKOTAS.
THAT SAME POTENT SHORTWAVE IS GOING TO HELP PULL THE LOW IN
SOUTHWEST NEBRASKA UP INTO NORTHWEST ONTARIO...DRAGGING ITS COLD
FRONT TO AROUND I-35 IN MINNESOTA BY 00Z. THERE STILL REMAINS SOME
SLIGHT TIMING DIFFERENCES...BUT IT APPEARS I-35 IS ABOUT THE
FARTHEST EASTWARD EXTENT NOW. A DRY...CAPPED AIRMASS PRESENT AHEAD
OF THE FRONT WILL PREVENT ANY PRE-FRONTAL CONVECTION. AS HAS BEEN
ADVERTISED FOR THE PAST MANY DAYS...IT APPEARS ANY CONVECTION WILL
DEVELOP ON AND BEHIND THE FRONT...WHERE GREATER DPVA CAN INTERACT
WITH HIGHER PRECIPITABLE WATER AND INCREASING LOW TO MID-LEVEL
FRONTOGENESIS. IN FACT...THE FRONTOGENESIS DOES LOOK QUITE STRONG
BEHIND THE FRONT IN WESTERN MINNESOTA AT 00Z. GIVEN THE POSITION OF
THE FRONT AT 00Z...HAVE REMOVED THE 20 PERCENT PRECIPITATION
CHANCES. OTHERWISE...A MOSTLY SUNNY DAY IS ON TAP WITH HIGHS PRETTY
SIMILAR TO YESTERDAY GIVEN 850MB TEMPS HOLDING STEADY AND THE DRY
AIRMASS. HIGHS COULD GET CLOSE TO RECORDS....95 AT LA CROSSE AND
96 AT ROCHESTER. DEFINITELY WINDY...ESPECIALLY IN SOUTHEAST
MINNESOTA WHERE MAV/MET GUIDANCE HAVE WINDS AROUND 25 KT AT KRST
AND KTOB. HAVE DECLINED TO ISSUE ANY WIND ADVISORY...SINCE IT
APPEARS WIND SPEEDS SHOULD BE JUST BELOW CRITERIA. GUSTS
DEFINITELY LOOK TO BE BELOW ADVISORY...33-34 KT AT MOST.
TONIGHT AND MONDAY...THE COLD FRONT IS EXPECTED TO GET A STRONG PUSH
EASTWARD THROUGH THE FORECAST AREA DURING THIS PERIOD...IN RESPONSE
TO THE UPPER TROUGH MOVING INTO MANITOBA...NORTHWEST ONTARIO AND
MINNESOTA. GOOD AGREEMENT EXISTS THAT THE FRONT WILL BE THROUGH THE
ENTIRE AREA BY 18Z MONDAY. AGAIN...THE FOCUS FOR PRECIPITATION STAYS
ON AND BEHIND THE FRONT...DUE TO THE PRESENCE OF GREATER HEIGHT
FALLS...LOW TO MID-LEVEL FRONTOGENESIS AND PRECIPITABLE WATER.
REGARDING THE MOISTURE...PRECIPITABLE WATER VALUES ARE PROGGED TO
CLIMB TO 1.5 TO EVEN AS MUCH AS 1.9 INCHES ON AND JUST BEHIND THE
FRONT. NOTE THAT THE HIGHER MOISTURE IS SOMEWHAT IN A NARROW
RIBBON...SINCE THEY DROP TO 0.5 INCHES ABOUT 70 MILES WEST OF THE
FRONT. MAIN CONCERN IS CONVECTION ON AND JUST BEHIND THE FRONT IN
THE EVENING...SINCE MLCAPE VALUES OF 900-1200 J/KG AT 00Z WILL BE
FRONTOGENETICALLY LIFTED BACK TO THE WEST. NOTE THAT THIS
INSTABILITY DIMINISHES QUICKLY WITH LOSS OF DAYTIME HEATING.
STILL...THERE APPEARS TO BE A BRIEF PERIOD IN THE EVENING WHERE
BOWING SEGMENTS ARE POSSIBLE RIGHT ON THE FRONT DUE TO THE
COMBINATION OF THE INSTABILITY AND 0-3KM SHEAR OF 25-30 KT. NO HAIL
ANTICIPATED GIVEN DEEP WARM CLOUD DEPTHS...LACK OF SIGNIFICANT
INSTABILITY AND 0-6KM SHEAR ON AND JUST BEHIND THE FRONT ONLY
25-30KT LIMITING STORM HEIGHT. SEVERE RISK...THEREFORE...IS REALLY
RESTRICTED WEST OF A LINE FROM WABASHA MN TO NEW HAMPTON IOWA. WITH
THE STRONG FORCING IN THE EVENING...PRECIPITATION LOOKS CERTAIN WEST
OF THAT LINE. AS THE NIGHT ROLLS ON...MODEL FORECASTS HAVE THE LOW
TO MID-LEVEL FRONTOGENESIS WEAKENING...WHICH IN COMBINATION WITH THE
DYING INSTABILITY WILL CAUSE THE PRECIPITATION TO WEAKEN AND BREAK
UP. BY 12Z MONDAY...WE COULD BE LOOKING AT JUST SOME ISOLATED TO
SCATTERED SHOWERS AND PERHAPS A FEW THUNDERSTORMS...MOSTLY OVER THE
SOUTHEAST HALF OF THE AREA. AND BY 18Z...THE PRECIPITATION LOOKS TO
BE MOSTLY EAST OF THE AREA WITH THE DRY SLOT OF LOWER PRECIPITABLE
WATER VALUES IN PLACE. TAILORED THE PRECIPITATION CHANCES TO FOLLOW
THIS IDEA...WHICH IS ALSO VERY WELL AGREED UPON BY HIGHER RESOLUTION
MESOSCALE MODELS. OVERALL...FOLLOWED A BLEND OF GUIDANCE FOR LOWS.
850MB TEMPS DO COOL TO 12-16C BY 18Z MONDAY...THUS ANTICIPATED A
COOLER DAY...BUT SUNSHINE SHOULD ALLOW TEMPERATURES TO CLIMB INTO
THE UPPER 70S TO MID 80S.
MONDAY NIGHT THROUGH TUESDAY NIGHT...THIS PERIOD LOOKS MUCH COOLER
THAN WHAT WE HAVE SEEN AS OF LATE. TROUGHING SLIDES ACROSS THE AREA
MONDAY NIGHT...ALLOWING HIGH PRESSURE TO BUILD INTO THE AREA ON
TUESDAY. ACCOMPANYING THE UPPER TROUGH IS SOME COOLER 850MB TEMPS...
TANKING TO 4-7C BY 18Z TUESDAY. SOME MODELS LIKE THE 10.00Z NAM EVEN
SUGGEST TAYLOR COUNTY SEEING THE 850MB TEMPS DROP TO NEAR 0C AT 12Z.
ANY LOWER CLOUDS ACCOMPANYING THE THERMAL TROUGH LOOK TO STAY TO OUR
NORTH...SO PLENTY OF SUN SHOULD BE SEEN ON TUESDAY. STILL...MIXING
TO THE AFOREMENTIONED 850MB TEMPS ONLY RESULTS IN HIGHS FROM THE
UPPER 60S TO MID 70S. WINDS SHOULD START OFF BREEZY IN THE
MORNING...THEN DECREASE LATE IN THE AFTERNOON AS THE HIGH PRESSURE
AREA BUILDS IN. THAT BREEZE SHOULD KEEP TEMPERATURES MONDAY NIGHT
FROM DROPPING BELOW THE 50S...THOUGH IT IS POSSIBLE THAT TAYLOR AND
CLARK COUNTY COULD SEE READINGS IN THE UPPER 40S. ONE ITEM OF NOTE
FOR MONDAY NIGHT IS A SECONDARY COLD FRONT MOVING THROUGH DURING THE
EVENING. A BAND OF STRATUS MAY ACCOMPANY THE FRONT...BUT NO
PRECIPITATION IS ANTICIPATED WITH IT. TUESDAY NIGHT FOR THE MOST
PART LOOKS QUIET AS THE UPPER FLOW TURNS ZONAL AND ALLOWS THE DRY
SURFACE HIGH TO ONLY DRIFT TO THE EAST. ONE THING TO WATCH IS A
SHORTWAVE MOVING THROUGH THE ZONAL FLOW...REACHING THE SIOUX FALLS
AREA BY 12Z WEDNESDAY ACCORDING TO THE 10.00Z NAM/GFS. NOT
INTRODUCING ANY CHANCES OF PRECIPITATION WITH IT...SINCE THAT WILL
STAY OFF TO THE WEST. HOWEVER...WE COULD SEE AN INCREASE IN MID/HIGH
CLOUD COVER LATE IN THE NIGHT WEST OF THE MISSISSIPPI RIVER. CHILLY
NIGHT LIKELY...ESPECIALLY OVER WISCONSIN WITH CLEAR SKIES...DRY AIR
AND LIGHT WINDS ALL NIGHT. TRENDED TOWARDS THE LOWER OF GUIDANCE FOR
LOWS...WHICH RESULTS IN SOME LOWER 40S IN THE TYPICAL COLD SPOTS.
.LONG TERM...WEDNESDAY THROUGH SATURDAY NIGHT
257 AM CDT SUN JUN 10 2012
10.00Z ECMWF/CANADIAN/GFS AND GFS ENSEMBLES ARE IN GENERAL AGREEMENT
ON THE UPPER LEVEL PATTERN THROUGH THE LONG TERM PERIOD. THEY ALL
INDICATE THAT THE ZONAL FLOW THAT DEVELOPED TUESDAY WILL TRANSITION
TO TROUGHING IN THE WESTERN U.S. AND RIDGING BACK OVER THE EASTERN
U.S. BY THURSDAY NIGHT. BEYOND THIS...QUESTIONS EXIST ON HOW QUICK
THE WESTERN TROUGHING PROGRESSES EASTWARD...WITH THE 10.00Z GFS
SEEMING TO BE TOO FAST COMPARED TO ITS ENSEMBLES AND ECMWF. THIS IS
A TYPICAL BIAS OF THE GFS TOO. THEREFORE...WILL LEAN THE LONG TERM
CLOSER TOWARDS THE ECMWF...WHICH KEEPS THE TROUGHING BOTTLED UP OVER
THE WESTERN U.S. RIGHT INTO SUNDAY. OVERALL...PRECIPITATION CHANCES
LOOK PRETTY LOW THROUGHOUT MUCH OF THE LONG TERM. ONE FOCUS POINT
IS WEDNESDAY NIGHT NORTH OF I-90 WITH A SHORTWAVE MOVING THROUGH
THE FLOW. HOWEVER...THE LOW LEVEL AIRMASS MAY BE TOO DRY TO SUPPORT
PRECIP. THEREFORE...CHANCES REMAIN AROUND 20 PERCENT. NEXT FORECAST
MAY BE ABLE TO PULL THESE. REMOVED CHANCES FOR THURSDAY THROUGH
FRIDAY WITH HIGH PRESSURE AND UPPER RIDGING IN CONTROL. NEXT FOCUS
POINT FOR PRECIPITATION IS FRIDAY NIGHT AND SATURDAY...UNDER THE
ASSUMPTION THAT SOME HEIGHT FALLS WILL BE OCCURRING WITH THE WESTERN
TROUGH MOVING SLIGHTLY EAST. KEPT FRIDAY NIGHT CHANCES AROUND 20 AND
IN SOUTHEAST MN/NORTHEAST IA. THESE THEN SPREAD EAST ON SATURDAY. IT
IS ENTIRELY POSSIBLE THIS PERIOD COULD BE DRY TOO...EITHER FROM THE
TROUGH BEING SLOWER OR THE AIRMASS NOT BEING AS MOIST AS MODELS
ADVERTISE. CERTAINLY THE MAINLY DRY DAYS EXPECTED THIS MONDAY
THROUGH BASICALLY FRIDAY WILL END UP EVAPOTRANSPIRATING ANY RAIN
RECEIVED FROM TONIGHT.
TEMPERATURES WILL START OFF NEAR NORMAL ON WEDNESDAY WITH 850MB
TEMPS BETWEEN 10-12C. AS THE UPPER RIDGING BUILDS...850MB TEMPS
CLIMB...BRINGING TEMPERATURES BACK ABOVE NORMAL. IN FACT...THERE IS
A CHANCE READINGS COULD GET BACK UP TO NEAR 90 FOR FRIDAY AND SATURDAY.
&&
.AVIATION...THIS AFTERNOON THROUGH MONDAY
1227 PM CDT SUN JUN 10 2012
PRESSURE GRADIENT CONTINUED TO TIGHTEN OVER THE AREA LATE THIS
MORNING/THIS AFTERNOON...AHEAD OF LOW PRESSURE AND A COLD FRONT
HEADED EAST FROM NEAR THE MN/DAKOTAS BORDER. BRISK SOUTH WINDS
15-25KT G30-35KTS EXPECTED ACROSS THE AREA THRU THIS AFTERNOON...
WITH THE STRONGEST WINDS OVER THE HIGHER TERRAIN/RIDGE TOP AREAS.
WINDS WILL DIMINISH AS THE FRONT APPROACHES AND DIURNAL COOLING
BEGINS LATE THIS AFTERNOON/EARLY THIS EVENING.
CONVECTION EXPECTED TO ERUPT ALONG THE COLD FRONT ACROSS CENTRAL
MN TO WESTERN IA AROUND MID-AFTERNOON AS IT PUSHES INTO THE
INCREASINGLY MOIST/UNSTABLE AIRMASS IN PLACE AHEAD OF IT. FAIRLY
SOLID LINE OF SHRA/TSRA SLATED TO PUSH INTO AREAS WEST OF THE MS
RIVER DURING THE MID TO LATE EVENING HOURS. SOME STRONG/GUSTY WEST
WINDS EXPECTED WITH THIS LINE OF SHRA/TSRA AS IT MOVES IN THRU THE
EVENING HOURS...AND ADDED THIS TO BOTH KRST/KLSE AS THE MAIN LINE OF
CONVECTION PASSES. TIMING LOOKS TO BE 04-06Z AT KRST AND 06-08Z AT
KLSE. LINE OF SHRA/TSRA WILL BE WEAKENING AS APPROACHES/CROSSES THE
MS RIVER INTO WI...DUE TO TIME OF DAY AND DECREASE OF INSTABILITY.
CIGS/VSBYS LOOKING TO DROP INTO MVFR AS THE LINE PASSES...QUICKLY
IMPROVING LATER TONIGHT AS DRIER/COOLER AIR MOVES IN BEHIND THE
LINE/FRONT. IF A STRONGER TSRA CORE GOES OVER ONE OF THE TAF
SITES...CIGS/VSBYS LIKELY TO DROP TO IFR FOR A BRIEF PERIOD AS IT
PASSES. GIVEN POTENTIAL TIMING PROBLEMS...LEFT ANY IFR MENTION OUT
OF THE TAFS FOR NOW. VFR CONDITIONS ON TAP FOR MON AS FRONT
CONTINUES TO MOVE EAST AND DRIER/COOLER CANADIAN HIGH PRESSURE
BUILDS INTO MN/WI BEHIND IT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
257 AM CDT SUN JUN 10 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...DAS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
559 AM CDT SUN JUN 10 2012
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
257 AM CDT SUN JUN 10 2012
MAIN FORECAST CONCERN IS ON PRECIPITATION CHANCES TONIGHT INTO
MONDAY...ALONG WITH ANY SEVERE RISK THIS EVENING.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED TROUGHING OVER THE NORTHERN ROCKIES AND RIDGING OVER THE
WESTERN GREAT LAKES REGION. SUBSIDENCE AND PLENTY OF DRY AIR
UNDERNEATH THE UPPER RIDGING...NOTED BY PRECIPITABLE WATER VALUES
FROM 00Z SOUNDINGS AT MPX AND DVN NEAR 0.7 INCHES...HAS CONTINUED TO
KEEP SKIES CLEAR. A 30-40 KT SOUTHWEST WIND AT 850MB PER PROFILER
DATA STILL EXISTS FROM EASTERN KANSAS INTO THE FORECAST AREA...WHICH
HAS HELPED TO MAINTAIN TEMPERATURES AROUND 18C PER 00Z SOUNDINGS AND
RAP ANALYSIS. THE LOW LEVEL JET TOO IS ALSO HELPING TO BRING
SLIGHTLY MORE MOISTURE NORTHEASTWARD...WITH 1 INCH PRECIPITABLE
WATER VALUES NOW ENTERING FAR SOUTHERN IOWA AS SEEN ON GOES SOUNDER
IMAGERY. HIGHER MOISTURE IS PRESENT OVER THE DAKOTAS...WHERE THE
COMBINATION OF A SLIGHTLY STRONGER LOW LEVEL JET IS IMPINGING ON
DPVA DOWNSTREAM OF THE NORTHERN ROCKIES TROUGH...LEADING TO
CONVECTIVE DEVELOPMENT. RAP ANALYSIS INDICATING PRECIPITABLE WATER
VALUES THERE NEAR 1.5 INCHES. MUCH OF THE CONVECTION LIES BEHIND A
COLD FRONT...STRETCHING FROM JUST WEST OF FARGO DOWN INTO SOUTHWEST
NEBRASKA WHERE A 987MB LOW IS PRESENT.
TODAY...THE NORTHERN ROCKIES TROUGH IS PROGGED BY ALL MODELS TO LIFT
TO THE NORTHEAST...INDUCED PARTLY BY A POTENT SHORTWAVE AT THE BASE
OF THE TROUGH LIFTING NORTHEAST. BY 00Z MONDAY...THE CORE IS
FORECAST TO BE SITUATED FROM SASKATCHEWAN INTO THE WESTERN DAKOTAS.
THAT SAME POTENT SHORTWAVE IS GOING TO HELP PULL THE LOW IN
SOUTHWEST NEBRASKA UP INTO NORTHWEST ONTARIO...DRAGGING ITS COLD
FRONT TO AROUND I-35 IN MINNESOTA BY 00Z. THERE STILL REMAINS SOME
SLIGHT TIMING DIFFERENCES...BUT IT APPEARS I-35 IS ABOUT THE
FARTHEST EASTWARD EXTENT NOW. A DRY...CAPPED AIRMASS PRESENT AHEAD
OF THE FRONT WILL PREVENT ANY PRE-FRONTAL CONVECTION. AS HAS BEEN
ADVERTISED FOR THE PAST MANY DAYS...IT APPEARS ANY CONVECTION WILL
DEVELOP ON AND BEHIND THE FRONT...WHERE GREATER DPVA CAN INTERACT
WITH HIGHER PRECIPITABLE WATER AND INCREASING LOW TO MID-LEVEL
FRONTOGENESIS. IN FACT...THE FRONTOGENESIS DOES LOOK QUITE STRONG
BEHIND THE FRONT IN WESTERN MINNESOTA AT 00Z. GIVEN THE POSITION OF
THE FRONT AT 00Z...HAVE REMOVED THE 20 PERCENT PRECIPITATION
CHANCES. OTHERWISE...A MOSTLY SUNNY DAY IS ON TAP WITH HIGHS PRETTY
SIMILAR TO YESTERDAY GIVEN 850MB TEMPS HOLDING STEADY AND THE DRY
AIRMASS. HIGHS COULD GET CLOSE TO RECORDS....95 AT LA CROSSE AND
96 AT ROCHESTER. DEFINITELY WINDY...ESPECIALLY IN SOUTHEAST
MINNESOTA WHERE MAV/MET GUIDANCE HAVE WINDS AROUND 25 KT AT KRST
AND KTOB. HAVE DECLINED TO ISSUE ANY WIND ADVISORY...SINCE IT
APPEARS WIND SPEEDS SHOULD BE JUST BELOW CRITERIA. GUSTS
DEFINITELY LOOK TO BE BELOW ADVISORY...33-34 KT AT MOST.
TONIGHT AND MONDAY...THE COLD FRONT IS EXPECTED TO GET A STRONG PUSH
EASTWARD THROUGH THE FORECAST AREA DURING THIS PERIOD...IN RESPONSE
TO THE UPPER TROUGH MOVING INTO MANITOBA...NORTHWEST ONTARIO AND
MINNESOTA. GOOD AGREEMENT EXISTS THAT THE FRONT WILL BE THROUGH THE
ENTIRE AREA BY 18Z MONDAY. AGAIN...THE FOCUS FOR PRECIPITATION STAYS
ON AND BEHIND THE FRONT...DUE TO THE PRESENCE OF GREATER HEIGHT
FALLS...LOW TO MID-LEVEL FRONTOGENESIS AND PRECIPITABLE WATER.
REGARDING THE MOISTURE...PRECIPITABLE WATER VALUES ARE PROGGED TO
CLIMB TO 1.5 TO EVEN AS MUCH AS 1.9 INCHES ON AND JUST BEHIND THE
FRONT. NOTE THAT THE HIGHER MOISTURE IS SOMEWHAT IN A NARROW
RIBBON...SINCE THEY DROP TO 0.5 INCHES ABOUT 70 MILES WEST OF THE
FRONT. MAIN CONCERN IS CONVECTION ON AND JUST BEHIND THE FRONT IN
THE EVENING...SINCE MLCAPE VALUES OF 900-1200 J/KG AT 00Z WILL BE
FRONTOGENETICALLY LIFTED BACK TO THE WEST. NOTE THAT THIS
INSTABILITY DIMINISHES QUICKLY WITH LOSS OF DAYTIME HEATING.
STILL...THERE APPEARS TO BE A BRIEF PERIOD IN THE EVENING WHERE
BOWING SEGMENTS ARE POSSIBLE RIGHT ON THE FRONT DUE TO THE
COMBINATION OF THE INSTABILITY AND 0-3KM SHEAR OF 25-30 KT. NO HAIL
ANTICIPATED GIVEN DEEP WARM CLOUD DEPTHS...LACK OF SIGNIFICANT
INSTABILITY AND 0-6KM SHEAR ON AND JUST BEHIND THE FRONT ONLY
25-30KT LIMITING STORM HEIGHT. SEVERE RISK...THEREFORE...IS REALLY
RESTRICTED WEST OF A LINE FROM WABASHA MN TO NEW HAMPTON IOWA. WITH
THE STRONG FORCING IN THE EVENING...PRECIPITATION LOOKS CERTAIN WEST
OF THAT LINE. AS THE NIGHT ROLLS ON...MODEL FORECASTS HAVE THE LOW
TO MID-LEVEL FRONTOGENESIS WEAKENING...WHICH IN COMBINATION WITH THE
DYING INSTABILITY WILL CAUSE THE PRECIPITATION TO WEAKEN AND BREAK
UP. BY 12Z MONDAY...WE COULD BE LOOKING AT JUST SOME ISOLATED TO
SCATTERED SHOWERS AND PERHAPS A FEW THUNDERSTORMS...MOSTLY OVER THE
SOUTHEAST HALF OF THE AREA. AND BY 18Z...THE PRECIPITATION LOOKS TO
BE MOSTLY EAST OF THE AREA WITH THE DRY SLOT OF LOWER PRECIPITABLE
WATER VALUES IN PLACE. TAILORED THE PRECIPITATION CHANCES TO FOLLOW
THIS IDEA...WHICH IS ALSO VERY WELL AGREED UPON BY HIGHER RESOLUTION
MESOSCALE MODELS. OVERALL...FOLLOWED A BLEND OF GUIDANCE FOR LOWS.
850MB TEMPS DO COOL TO 12-16C BY 18Z MONDAY...THUS ANTICIPATED A
COOLER DAY...BUT SUNSHINE SHOULD ALLOW TEMPERATURES TO CLIMB INTO
THE UPPER 70S TO MID 80S.
MONDAY NIGHT THROUGH TUESDAY NIGHT...THIS PERIOD LOOKS MUCH COOLER
THAN WHAT WE HAVE SEEN AS OF LATE. TROUGHING SLIDES ACROSS THE AREA
MONDAY NIGHT...ALLOWING HIGH PRESSURE TO BUILD INTO THE AREA ON
TUESDAY. ACCOMPANYING THE UPPER TROUGH IS SOME COOLER 850MB TEMPS...
TANKING TO 4-7C BY 18Z TUESDAY. SOME MODELS LIKE THE 10.00Z NAM EVEN
SUGGEST TAYLOR COUNTY SEEING THE 850MB TEMPS DROP TO NEAR 0C AT 12Z.
ANY LOWER CLOUDS ACCOMPANYING THE THERMAL TROUGH LOOK TO STAY TO OUR
NORTH...SO PLENTY OF SUN SHOULD BE SEEN ON TUESDAY. STILL...MIXING
TO THE AFOREMENTIONED 850MB TEMPS ONLY RESULTS IN HIGHS FROM THE
UPPER 60S TO MID 70S. WINDS SHOULD START OFF BREEZY IN THE
MORNING...THEN DECREASE LATE IN THE AFTERNOON AS THE HIGH PRESSURE
AREA BUILDS IN. THAT BREEZE SHOULD KEEP TEMPERATURES MONDAY NIGHT
FROM DROPPING BELOW THE 50S...THOUGH IT IS POSSIBLE THAT TAYLOR AND
CLARK COUNTY COULD SEE READINGS IN THE UPPER 40S. ONE ITEM OF NOTE
FOR MONDAY NIGHT IS A SECONDARY COLD FRONT MOVING THROUGH DURING THE
EVENING. A BAND OF STRATUS MAY ACCOMPANY THE FRONT...BUT NO
PRECIPITATION IS ANTICIPATED WITH IT. TUESDAY NIGHT FOR THE MOST
PART LOOKS QUIET AS THE UPPER FLOW TURNS ZONAL AND ALLOWS THE DRY
SURFACE HIGH TO ONLY DRIFT TO THE EAST. ONE THING TO WATCH IS A
SHORTWAVE MOVING THROUGH THE ZONAL FLOW...REACHING THE SIOUX FALLS
AREA BY 12Z WEDNESDAY ACCORDING TO THE 10.00Z NAM/GFS. NOT
INTRODUCING ANY CHANCES OF PRECIPITATION WITH IT...SINCE THAT WILL
STAY OFF TO THE WEST. HOWEVER...WE COULD SEE AN INCREASE IN MID/HIGH
CLOUD COVER LATE IN THE NIGHT WEST OF THE MISSISSIPPI RIVER. CHILLY
NIGHT LIKELY...ESPECIALLY OVER WISCONSIN WITH CLEAR SKIES...DRY AIR
AND LIGHT WINDS ALL NIGHT. TRENDED TOWARDS THE LOWER OF GUIDANCE FOR
LOWS...WHICH RESULTS IN SOME LOWER 40S IN THE TYPICAL COLD SPOTS.
.LONG TERM...WEDNESDAY THROUGH SATURDAY NIGHT
257 AM CDT SUN JUN 10 2012
10.00Z ECMWF/CANADIAN/GFS AND GFS ENSEMBLES ARE IN GENERAL AGREEMENT
ON THE UPPER LEVEL PATTERN THROUGH THE LONG TERM PERIOD. THEY ALL
INDICATE THAT THE ZONAL FLOW THAT DEVELOPED TUESDAY WILL TRANSITION
TO TROUGHING IN THE WESTERN U.S. AND RIDGING BACK OVER THE EASTERN
U.S. BY THURSDAY NIGHT. BEYOND THIS...QUESTIONS EXIST ON HOW QUICK
THE WESTERN TROUGHING PROGRESSES EASTWARD...WITH THE 10.00Z GFS
SEEMING TO BE TOO FAST COMPARED TO ITS ENSEMBLES AND ECMWF. THIS IS
A TYPICAL BIAS OF THE GFS TOO. THEREFORE...WILL LEAN THE LONG TERM
CLOSER TOWARDS THE ECMWF...WHICH KEEPS THE TROUGHING BOTTLED UP OVER
THE WESTERN U.S. RIGHT INTO SUNDAY. OVERALL...PRECIPITATION CHANCES
LOOK PRETTY LOW THROUGHOUT MUCH OF THE LONG TERM. ONE FOCUS POINT
IS WEDNESDAY NIGHT NORTH OF I-90 WITH A SHORTWAVE MOVING THROUGH
THE FLOW. HOWEVER...THE LOW LEVEL AIRMASS MAY BE TOO DRY TO SUPPORT
PRECIP. THEREFORE...CHANCES REMAIN AROUND 20 PERCENT. NEXT FORECAST
MAY BE ABLE TO PULL THESE. REMOVED CHANCES FOR THURSDAY THROUGH
FRIDAY WITH HIGH PRESSURE AND UPPER RIDGING IN CONTROL. NEXT FOCUS
POINT FOR PRECIPITATION IS FRIDAY NIGHT AND SATURDAY...UNDER THE
ASSUMPTION THAT SOME HEIGHT FALLS WILL BE OCCURRING WITH THE WESTERN
TROUGH MOVING SLIGHTLY EAST. KEPT FRIDAY NIGHT CHANCES AROUND 20 AND
IN SOUTHEAST MN/NORTHEAST IA. THESE THEN SPREAD EAST ON SATURDAY. IT
IS ENTIRELY POSSIBLE THIS PERIOD COULD BE DRY TOO...EITHER FROM THE
TROUGH BEING SLOWER OR THE AIRMASS NOT BEING AS MOIST AS MODELS
ADVERTISE. CERTAINLY THE MAINLY DRY DAYS EXPECTED THIS MONDAY
THROUGH BASICALLY FRIDAY WILL END UP EVAPOTRANSPORATING ANY RAIN
RECEIVED FROM TONIGHT.
TEMPERATURES WILL START OFF NEAR NORMAL ON WEDNESDAY WITH 850MB
TEMPS BETWEEN 10-12C. AS THE UPPER RIDGING BUILDS...850MB TEMPS
CLIMB...BRINGING TEMPERATURES BACK ABOVE NORMAL. IN FACT...THERE IS
A CHANCE READINGS COULD GET BACK UP TO NEAR 90 FOR FRIDAY AND SATURDAY.
&&
.AVIATION...TODAY AND TONIGHT
559 AM CDT SUN JUN 10 2012
CONCERNS THROUGH THE PERIOD INCLUDE WINDS TODAY AND THEN
THUNDERSTORM CHANCES TONIGHT.
TIGHT PRESSURE GRADIENT AHEAD OF AN APPROACHING COLD FRONT FROM
THE NORTHERN AND CENTRAL PLAINS WILL PRODUCE GUSTY SOUTH WINDS
ACROSS THE REGION. THIS WILL BE ESPECIALLY TRUE IN THE HIGH MORE-
OPEN AREAS OF NORTHEAST IA/SOUTHEAST MN...INCLUDING THE KRST TAF
SITE. SUSTAINED SOUTH WINDS OF 20-25KT WITH GUSTS NEAR 35KT ARE
EXPECTED AT KRST BY 15Z...LASTING THROUGH THE AFTERNOON. SLIGHTLY
LIGHTER WINDS ARE EXPECTED AT KLSE WITH SUSTAINED WINDS OF 15-20KT
WITH GUSTS NEAR 30KT. NEXT ON THE DOCKET WILL BE THUNDERSTORM
CHANCES THIS EVENING/OVERNIGHT AS THE COLD FRONT MOVES INTO THE
AREA. FAIRLY CONFIDENT THAT KRST WILL SEE A PRETTY SOLID LINE OF
TS MOVE IN BY 03Z...LASTING TIL ABOUT 06Z BEFORE TRANSITIONING TO
SHRA WITH DIMINISHING INSTABILITY. LOOK FOR THE SHRA TO LAST UNTIL
12Z...THEN SHIFT EAST. FOR KLSE...THUNDER CHANCES WILL BE A BIT
TRICKIER AS THE LINE OF CONVECTION IS EXPECTED TO DIMINISH IN
COVERAGE AND INTENSITY AS IT MOVES TOWARD THE MISSISSIPPI LATER IN
THE EVENING/OVERNIGHT. PLAN ON KEEPING VCTS IN FROM 06Z TO ABOUT
09Z...THEN DIMINISH TO SHRA AFTER 09Z. ALSO...LOOK FOR A WINDSHIFT
FROM SOUTH TO THE NORTHWEST WITH COLD FROPA //AROUND 06Z FOR KRST
AND 09Z AT KLSE. VFR CONDITIONS EXPECTED THROUGH FROPA...BUT MODEL
SOUNDINGS HINTING AT A BRIEF BOUT OF POST FRONTAL MVFR
STRATOCUMULUS AT KRST IN THE 06-10Z TIMEFRAME. KLSE EXPECTED TO
REMAIN VFR.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
257 AM CDT SUN JUN 10 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...DAS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
257 AM CDT SUN JUN 10 2012
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
257 AM CDT SUN JUN 10 2012
MAIN FORECAST CONCERN IS ON PRECIPITATION CHANCES TONIGHT INTO
MONDAY...ALONG WITH ANY SEVERE RISK THIS EVENING.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED TROUGHING OVER THE NORTHERN ROCKIES AND RIDGING OVER THE
WESTERN GREAT LAKES REGION. SUBSIDENCE AND PLENTY OF DRY AIR
UNDERNEATH THE UPPER RIDGING...NOTED BY PRECIPITABLE WATER VALUES
FROM 00Z SOUNDINGS AT MPX AND DVN NEAR 0.7 INCHES...HAS CONTINUED TO
KEEP SKIES CLEAR. A 30-40 KT SOUTHWEST WIND AT 850MB PER PROFILER
DATA STILL EXISTS FROM EASTERN KANSAS INTO THE FORECAST AREA...WHICH
HAS HELPED TO MAINTAIN TEMPERATURES AROUND 18C PER 00Z SOUNDINGS AND
RAP ANALYSIS. THE LOW LEVEL JET TOO IS ALSO HELPING TO BRING
SLIGHTLY MORE MOISTURE NORTHEASTWARD...WITH 1 INCH PRECIPITABLE
WATER VALUES NOW ENTERING FAR SOUTHERN IOWA AS SEEN ON GOES SOUNDER
IMAGERY. HIGHER MOISTURE IS PRESENT OVER THE DAKOTAS...WHERE THE
COMBINATION OF A SLIGHTLY STRONGER LOW LEVEL JET IS IMPINGING ON
DPVA DOWNSTREAM OF THE NORTHERN ROCKIES TROUGH...LEADING TO
CONVECTIVE DEVELOPMENT. RAP ANALYSIS INDICATING PRECIPITABLE WATER
VALUES THERE NEAR 1.5 INCHES. MUCH OF THE CONVECTION LIES BEHIND A
COLD FRONT...STRETCHING FROM JUST WEST OF FARGO DOWN INTO SOUTHWEST
NEBRASKA WHERE A 987MB LOW IS PRESENT.
TODAY...THE NORTHERN ROCKIES TROUGH IS PROGGED BY ALL MODELS TO LIFT
TO THE NORTHEAST...INDUCED PARTLY BY A POTENT SHORTWAVE AT THE BASE
OF THE TROUGH LIFTING NORTHEAST. BY 00Z MONDAY...THE CORE IS
FORECAST TO BE SITUATED FROM SASKATCHEWAN INTO THE WESTERN DAKOTAS.
THAT SAME POTENT SHORTWAVE IS GOING TO HELP PULL THE LOW IN
SOUTHWEST NEBRASKA UP INTO NORTHWEST ONTARIO...DRAGGING ITS COLD
FRONT TO AROUND I-35 IN MINNESOTA BY 00Z. THERE STILL REMAINS SOME
SLIGHT TIMING DIFFERENCES...BUT IT APPEARS I-35 IS ABOUT THE
FARTHEST EASTWARD EXTENT NOW. A DRY...CAPPED AIRMASS PRESENT AHEAD
OF THE FRONT WILL PREVENT ANY PRE-FRONTAL CONVECTION. AS HAS BEEN
ADVERTISED FOR THE PAST MANY DAYS...IT APPEARS ANY CONVECTION WILL
DEVELOP ON AND BEHIND THE FRONT...WHERE GREATER DPVA CAN INTERACT
WITH HIGHER PRECIPITABLE WATER AND INCREASING LOW TO MID-LEVEL
FRONTOGENESIS. IN FACT...THE FRONTOGENESIS DOES LOOK QUITE STRONG
BEHIND THE FRONT IN WESTERN MINNESOTA AT 00Z. GIVEN THE POSITION OF
THE FRONT AT 00Z...HAVE REMOVED THE 20 PERCENT PRECIPITATION
CHANCES. OTHERWISE...A MOSTLY SUNNY DAY IS ON TAP WITH HIGHS PRETTY
SIMILAR TO YESTERDAY GIVEN 850MB TEMPS HOLDING STEADY AND THE DRY
AIRMASS. HIGHS COULD GET CLOSE TO RECORDS....95 AT LA CROSSE AND
96 AT ROCHESTER. DEFINITELY WINDY...ESPECIALLY IN SOUTHEAST
MINNESOTA WHERE MAV/MET GUIDANCE HAVE WINDS AROUND 25 KT AT KRST
AND KTOB. HAVE DECLINED TO ISSUE ANY WIND ADVISORY...SINCE IT
APPEARS WIND SPEEDS SHOULD BE JUST BELOW CRITERIA. GUSTS
DEFINITELY LOOK TO BE BELOW ADVISORY...33-34 KT AT MOST.
TONIGHT AND MONDAY...THE COLD FRONT IS EXPECTED TO GET A STRONG PUSH
EASTWARD THROUGH THE FORECAST AREA DURING THIS PERIOD...IN RESPONSE
TO THE UPPER TROUGH MOVING INTO MANITOBA...NORTHWEST ONTARIO AND
MINNESOTA. GOOD AGREEMENT EXISTS THAT THE FRONT WILL BE THROUGH THE
ENTIRE AREA BY 18Z MONDAY. AGAIN...THE FOCUS FOR PRECIPITATION STAYS
ON AND BEHIND THE FRONT...DUE TO THE PRESENCE OF GREATER HEIGHT
FALLS...LOW TO MID-LEVEL FRONTOGENESIS AND PRECIPITABLE WATER.
REGARDING THE MOISTURE...PRECIPITABLE WATER VALUES ARE PROGGED TO
CLIMB TO 1.5 TO EVEN AS MUCH AS 1.9 INCHES ON AND JUST BEHIND THE
FRONT. NOTE THAT THE HIGHER MOISTURE IS SOMEWHAT IN A NARROW
RIBBON...SINCE THEY DROP TO 0.5 INCHES ABOUT 70 MILES WEST OF THE
FRONT. MAIN CONCERN IS CONVECTION ON AND JUST BEHIND THE FRONT IN
THE EVENING...SINCE MLCAPE VALUES OF 900-1200 J/KG AT 00Z WILL BE
FRONTOGENETICALLY LIFTED BACK TO THE WEST. NOTE THAT THIS
INSTABILITY DIMINISHES QUICKLY WITH LOSS OF DAYTIME HEATING.
STILL...THERE APPEARS TO BE A BRIEF PERIOD IN THE EVENING WHERE
BOWING SEGMENTS ARE POSSIBLE RIGHT ON THE FRONT DUE TO THE
COMBINATION OF THE INSTABILITY AND 0-3KM SHEAR OF 25-30 KT. NO HAIL
ANTICIPATED GIVEN DEEP WARM CLOUD DEPTHS...LACK OF SIGNIFICANT
INSTABILITY AND 0-6KM SHEAR ON AND JUST BEHIND THE FRONT ONLY
25-30KT LIMITING STORM HEIGHT. SEVERE RISK...THEREFORE...IS REALLY
RESTRICTED WEST OF A LINE FROM WABASHA MN TO NEW HAMPTON IOWA. WITH
THE STRONG FORCING IN THE EVENING...PRECIPITATION LOOKS CERTAIN WEST
OF THAT LINE. AS THE NIGHT ROLLS ON...MODEL FORECASTS HAVE THE LOW
TO MID-LEVEL FRONTOGENESIS WEAKENING...WHICH IN COMBINATION WITH THE
DYING INSTABILITY WILL CAUSE THE PRECIPITATION TO WEAKEN AND BREAK
UP. BY 12Z MONDAY...WE COULD BE LOOKING AT JUST SOME ISOLATED TO
SCATTERED SHOWERS AND PERHAPS A FEW THUNDERSTORMS...MOSTLY OVER THE
SOUTHEAST HALF OF THE AREA. AND BY 18Z...THE PRECIPITATION LOOKS TO
BE MOSTLY EAST OF THE AREA WITH THE DRY SLOT OF LOWER PRECIPITABLE
WATER VALUES IN PLACE. TAILORED THE PRECIPITATION CHANCES TO FOLLOW
THIS IDEA...WHICH IS ALSO VERY WELL AGREED UPON BY HIGHER RESOLUTION
MESOSCALE MODELS. OVERALL...FOLLOWED A BLEND OF GUIDANCE FOR LOWS.
850MB TEMPS DO COOL TO 12-16C BY 18Z MONDAY...THUS ANTICIPATED A
COOLER DAY...BUT SUNSHINE SHOULD ALLOW TEMPERATURES TO CLIMB INTO
THE UPPER 70S TO MID 80S.
MONDAY NIGHT THROUGH TUESDAY NIGHT...THIS PERIOD LOOKS MUCH COOLER
THAN WHAT WE HAVE SEEN AS OF LATE. TROUGHING SLIDES ACROSS THE AREA
MONDAY NIGHT...ALLOWING HIGH PRESSURE TO BUILD INTO THE AREA ON
TUESDAY. ACCOMPANYING THE UPPER TROUGH IS SOME COOLER 850MB TEMPS...
TANKING TO 4-7C BY 18Z TUESDAY. SOME MODELS LIKE THE 10.00Z NAM EVEN
SUGGEST TAYLOR COUNTY SEEING THE 850MB TEMPS DROP TO NEAR 0C AT 12Z.
ANY LOWER CLOUDS ACCOMPANYING THE THERMAL TROUGH LOOK TO STAY TO OUR
NORTH...SO PLENTY OF SUN SHOULD BE SEEN ON TUESDAY. STILL...MIXING
TO THE AFOREMENTIONED 850MB TEMPS ONLY RESULTS IN HIGHS FROM THE
UPPER 60S TO MID 70S. WINDS SHOULD START OFF BREEZY IN THE
MORNING...THEN DECREASE LATE IN THE AFTERNOON AS THE HIGH PRESSURE
AREA BUILDS IN. THAT BREEZE SHOULD KEEP TEMPERATURES MONDAY NIGHT
FROM DROPPING BELOW THE 50S...THOUGH IT IS POSSIBLE THAT TAYLOR AND
CLARK COUNTY COULD SEE READINGS IN THE UPPER 40S. ONE ITEM OF NOTE
FOR MONDAY NIGHT IS A SECONDARY COLD FRONT MOVING THROUGH DURING THE
EVENING. A BAND OF STRATUS MAY ACCOMPANY THE FRONT...BUT NO
PRECIPITATION IS ANTICIPATED WITH IT. TUESDAY NIGHT FOR THE MOST
PART LOOKS QUIET AS THE UPPER FLOW TURNS ZONAL AND ALLOWS THE DRY
SURFACE HIGH TO ONLY DRIFT TO THE EAST. ONE THING TO WATCH IS A
SHORTWAVE MOVING THROUGH THE ZONAL FLOW...REACHING THE SIOUX FALLS
AREA BY 12Z WEDNESDAY ACCORDING TO THE 10.00Z NAM/GFS. NOT
INTRODUCING ANY CHANCES OF PRECIPITATION WITH IT...SINCE THAT WILL
STAY OFF TO THE WEST. HOWEVER...WE COULD SEE AN INCREASE IN MID/HIGH
CLOUD COVER LATE IN THE NIGHT WEST OF THE MISSISSIPPI RIVER. CHILLY
NIGHT LIKELY...ESPECIALLY OVER WISCONSIN WITH CLEAR SKIES...DRY AIR
AND LIGHT WINDS ALL NIGHT. TRENDED TOWARDS THE LOWER OF GUIDANCE FOR
LOWS...WHICH RESULTS IN SOME LOWER 40S IN THE TYPICAL COLD SPOTS.
.LONG TERM...WEDNESDAY THROUGH SATURDAY NIGHT
257 AM CDT SUN JUN 10 2012
10.00Z ECMWF/CANADIAN/GFS AND GFS ENSEMBLES ARE IN GENERAL AGREEMENT
ON THE UPPER LEVEL PATTERN THROUGH THE LONG TERM PERIOD. THEY ALL
INDICATE THAT THE ZONAL FLOW THAT DEVELOPED TUESDAY WILL TRANSITION
TO TROUGHING IN THE WESTERN U.S. AND RIDGING BACK OVER THE EASTERN
U.S. BY THURSDAY NIGHT. BEYOND THIS...QUESTIONS EXIST ON HOW QUICK
THE WESTERN TROUGHING PROGRESSES EASTWARD...WITH THE 10.00Z GFS
SEEMING TO BE TOO FAST COMPARED TO ITS ENSEMBLES AND ECMWF. THIS IS
A TYPICAL BIAS OF THE GFS TOO. THEREFORE...WILL LEAN THE LONG TERM
CLOSER TOWARDS THE ECMWF...WHICH KEEPS THE TROUGHING BOTTLED UP OVER
THE WESTERN U.S. RIGHT INTO SUNDAY. OVERALL...PRECIPITATION CHANCES
LOOK PRETTY LOW THROUGHOUT MUCH OF THE LONG TERM. ONE FOCUS POINT
IS WEDNESDAY NIGHT NORTH OF I-90 WITH A SHORTWAVE MOVING THROUGH
THE FLOW. HOWEVER...THE LOW LEVEL AIRMASS MAY BE TOO DRY TO SUPPORT
PRECIP. THEREFORE...CHANCES REMAIN AROUND 20 PERCENT. NEXT FORECAST
MAY BE ABLE TO PULL THESE. REMOVED CHANCES FOR THURSDAY THROUGH
FRIDAY WITH HIGH PRESSURE AND UPPER RIDGING IN CONTROL. NEXT FOCUS
POINT FOR PRECIPITATION IS FRIDAY NIGHT AND SATURDAY...UNDER THE
ASSUMPTION THAT SOME HEIGHT FALLS WILL BE OCCURRING WITH THE WESTERN
TROUGH MOVING SLIGHTLY EAST. KEPT FRIDAY NIGHT CHANCES AROUND 20 AND
IN SOUTHEAST MN/NORTHEAST IA. THESE THEN SPREAD EAST ON SATURDAY. IT
IS ENTIRELY POSSIBLE THIS PERIOD COULD BE DRY TOO...EITHER FROM THE
TROUGH BEING SLOWER OR THE AIRMASS NOT BEING AS MOIST AS MODELS
ADVERTISE. CERTAINLY THE MAINLY DRY DAYS EXPECTED THIS MONDAY
THROUGH BASICALLY FRIDAY WILL END UP EVAPOTRANSPORATING ANY RAIN
RECEIVED FROM TONIGHT.
TEMPERATURES WILL START OFF NEAR NORMAL ON WEDNESDAY WITH 850MB
TEMPS BETWEEN 10-12C. AS THE UPPER RIDGING BUILDS...850MB TEMPS
CLIMB...BRINGING TEMPERATURES BACK ABOVE NORMAL. IN FACT...THERE IS
A CHANCE READINGS COULD GET BACK UP TO NEAR 90 FO
&&
.AVIATION...THROUGH 06Z MONDAY
1129 PM CDT SAT JUN 9 2012
MAIN FOCUS AT THE TAF SITES IS WITH THE STRONG AND GUSTY WINDS
SUNDAY AFTERNOON AND THE THUNDERSTORMS EXPECTED SUNDAY NIGHT.
WINDS WILL BE ON THE INCREASE THROUGH SUNDAY MORNING AND AFTERNOON
AS THE SURFACE PRESSURE GRADIENT TIGHTENS UP AHEAD OF A COLD
FRONT. SUSTAINED WINDS OF 15 TO 25 KTS WITH GUSTS OF UP TO 35KTS
ARE EXPECTED IN THE AFTERNOON.
A LINE OF SHOWERS AND THUNDERSTORMS IS EXPECTED TO MOVE INTO THE
REGION SUNDAY NIGHT AHEAD OF THIS COLD FRONT. THESE STORMS COULD
BRIEFLY BRING CONDITIONS DOWN BELOW VFR AND BRING SOME GUSTY WINDS
IN AS WELL. WINDS WILL SHIFT AROUND TO THE NORTHWEST AS THE FRONT
PASSES LATE IN THE EVENING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
257 AM CDT SUN JUN 10 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...HALBACH
CLIMATE......AJ
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1258 AM CDT TUE JUN 12 2012
.DISCUSSION...
903 PM CDT
UPDATE FOR REST OF TONIGHT...LAST HOPES FOR EVEN A STRAY SHOWER
OR THUNDERSHOWER FOR THE EASTERN PORTION OF THE LOCAL FORECAST
AREA IS QUICKLY DRYING UP...PUN INTENDED...AS THE PRE-FRONTAL
TROUGH HAS SHIFTED THE AXIS OF HIGHEST DEW POINTS AND GREATEST
POTENTIAL INSTABILITY E TO SW LOWER MI AND N CENTRAL IN. THE TRUE
COLD FRONT IS WELL DELINEATED FROM EXTREME SE WI SOUTHWESTWARD TO
W CENTRAL IL BY BOTH A WIND SHIFT FROM SW TO W AND NW...AS WELL AS
A DEW POINTS FALLING OFF TO THE UPPER AND MID 50S.
CURRENT REMAINING SLIGHT CHANCE POP NUMBERS FOR THE SE PORTION OF
THE FA WILL BE DROPPING OUT WITHIN AN HOUR OR TWO.
WITH CHANCES OF RAIN MINIMAL AT BEST THROUGH EARLY NEXT WEEK AT
LEAST...AND NEAR ZERO CHANCES THROUGH THE REST OF THIS WEEK
INCREASINGLY SERIOUS SOIL MOISTURE DEFICITS WILL LIKELY BE
CAUSING EVEN GREATER STRESS ON TREES AND CROPS.
TRS
//PREV DISCUSSION...
320 PM CDT
THE FORECAST CONCERNS ARE VERY MINIMAL THROUGH THE REST OF THE
WEEK WITH A CONTINUED DRY PATTERN. WILL BE MONITORING FOR A FEW
STORMS LATE THIS AFTERNOON INTO EARLY EVENING...OTHERWISE THAT MAY
WILL LIKELY BE ALL THAT IS ON THE SCOPE FOR QUITE A WHILE.
ISOLATED SHOWERS WITH A FEW STORMS REDEVELOPING OVER COOK COUNTY
AND SOUTH ALONG THE IL/IN STATE LINE...WHICH IS ALONG AND JUST
AHEAD OF A WEAK CONVERGENT AXIS AND APPARENT SHORT WAVE SEEN ON
SATELLITE. MID 80S TEMPERATURES AND UPPER 60S DEW POINTS ALONG AND
AHEAD OF THIS CORRIDOR HAS BUILT SURFACE BASED CAPE TO AROUND OR
SLIGHTLY OVER 2000 J/KG. THIS CONVECTION SHOULD LAST LONGER THAN
THE PREVIOUS ACTIVITY NEAR NOON BEING CLOSER TO THE SHORT WAVE
CENTER AND HAVING MORE INSTABILITY TO WORK WITH. UPPER LEVEL WIND
SHEAR LOOKS TO BE AROUND A MEAGER 20 KT PER PROFILER ANALYSIS. THE
BEHAVIOR OF THE STORM CORES IS LIKELY TO BE SOMEWHAT PULSY WITH
INSTABILITY IN THE DRIVERS SEAT...AND WITH LIMITED ATTENDANT SHEAR
IT LEAVES ONLY A VERY SMALL CHANCE FOR ANY TYPE OF SEVERE ACTIVITY.
THE SYSTEM UPPER TROUGH CENTER IS LOCATED ALONG THE MN/WESTERN
QUEBEC BORDER WITH PRIMARY HEIGHT FALLS...THE UPPER JET AXIS...AND
ASSOCIATED DEEPER ASCENT MOVING EAST FROM THERE. THIS FORCING HAS
AIDED SOME SHOWER DEVELOPMENT ALONG THE SURFACE COLD FRONT IN
WESTERN WI. THE COOL FRONT EXTENDS SOUTH FROM THERE WHERE IT WILL
MOVE INTO NW IL BY 4 PM AND EAST THROUGH THE FORECAST AREA THIS
EVE. THE WIND SHIFT IS GRADUAL FROM WEST SOUTHWEST TO WEST
NORTHWEST ALONG THE BOUNDARY...AND IT IS ACTUALLY AHEAD OF THE
STRONGEST MOISTURE CONVERGENCE. SO OVERALL CONVERGENCE IS LIMITED
AND FEEL THAT WILL BE THE CASE WITH ANY CONVECTION THAT WERE TO
TRIGGER ALONG IT...WHICH IS NOW APPEARING DOUBTFUL IN OUR AREA.
THE HRRR AND OTHER EXPLICIT CONVECTIVE MODELS AGREE IN THIS
LIMITED COVERAGE.
THE COOL FRONT WILL MOVE THROUGH THE AREA THIS EVENING AND IT
LOOKS LIKE THE BOUNDARY LAYER WILL STAY MIXED AS IT DOES
SUCH...WITH SOME GUSTS UP TO 20 MPH AS THE PRESSURE RISE AXIS
MOVES THROUGH. SUNNY AND DRY WEATHER WILL THEN ONCE AGAIN BE THE
STORY AS CANADIAN HIGH PRESSURE MOVES OVERHEAD TUESDAY NIGHT INTO
WEDNESDAY. THE REALLY ONLY WEATHER OF INTEREST FROM DAY TO DAY WILL
BE HOW LOW DEW POINTS WILL DROP DURING THE AFTERNOON MIXING...AND
TO WHAT DEGREE OF COOLING WILL THERE BE FROM THE LAKE. NORTHWEST
WINDS WILL BEGIN TO DECREASE TUESDAY AFTERNOON...POTENTIALLY
ALLOWING FOR A SLIGHT LAKE BREEZE INTO IL...BUT LIKELY INTO IN.
THIS MAY NOT DEVELOP UNTIL LATE AFTERNOON THOUGH...SO WIDESPREAD
HIGHS IN THE MID TO UPPER 70S ARE EXPECTED. UPSTREAM DEW POINTS
TODAY HAVE BEEN IN THE LOWER TO MID 40S ACROSS EASTERN SD. THIS
AND POSSIBLY EVEN LOWER SHOULD BE REALIZED DURING TUESDAY AFTERNOON
WITH PROJECTED MIXING TO 850 MB. THE AFTERNOON HUMIDITY WILL
REMAIN LOW...UNDER 25 PERCENT...ON WEDNESDAY AFTERNOON WITH THE
SYNOPTIC FLOW TURNING NORTHEAST AND THEN EAST.
INFLUENCE FROM THE LAKE WILL LIKELY CONTINUE TO MOVE INTO CHICAGO
DURING THE AFTERNOON ALL THE WAY THROUGH SATURDAY. THE UPPER LEVEL
HEIGHTS AND LOW-LEVEL THERMAL RIDGE BUILD MORE INTO THE AREA
THURSDAY NIGHT INTO SATURDAY. THE EC HAS SHOWN IN THE UPPER LEVEL
SW FLOW THAT SHORT WAVE ENERGY IS POSSIBLE WITHIN THIS AND MAY
DAMPEN THE RIDGE SLIGHTLY SATURDAY NIGHT INTO SUNDAY...AND HAVE A
SMALL CHANCE FOR POPS DURING PART OF THAT TIME. OTHERWISE...HAVE
COLLABORATED GOING DRIER THAN POPS AND DEW POINTS FROM GUIDANCE
BLENDS IN THE EXTENDED PER PERSISTENCE AND AN OVERALL STAGNANT
PATTERN.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* NO REAL CONCERNS THIS FORECAST PERIOD WITH VFR CONDITIONS
EXPECTED.
* NORTHWEST WINDS WILL INCREASE THROUGH LATE MORNING WITH GUSTS
INCREASING UP TO AROUND 18KT...BEFORE WINDS START TO SHIFT MORE
NORTH NORTHWEST AND EVENTUALLY SHIFT COMPLETELY OVER TO THE
NORTHEAST BY LATE AFTERNOON AND EARLY EVENING.
RODRIGUEZ
//DISCUSSION...UPDATED 06Z...
AS SURFACE TROUGH AND COLD FRONT CONTINUE TO SHIFT EAST OF THE
TERMINALS EARLY THIS MORNING...HIGH PRESSURE WILL BUILD EAST
ACROSS THE AREA. WITH HIGH PRESSURE BUILDING IN...ANY REMAINING
CLOUD COVER WILL ALSO EXIT WITH LIMITED CLOUD COVER EXPECTED FOR
THE REMAINDER OF THE TAF PERIOD.
WINDS HAVE SHIFTED TO THE WEST NORTHWEST EARLY THIS MORNING WITH
SOME BRIEF GUSTS REPORTED. ANY GUSTS SHOULD DIMINISH OVER THE NEXT
HOUR BEFORE INCREASING ONCE AGAIN BY MID MORNING. CAN EXPECT
NORTHWEST GUSTS TO AROUND 18KT WITH WINDS SHIFTING ALL THE WAY TO
THE NORTHEAST BY LATE THIS AFTERNOON AND EARLY EVENING. HAVE
SHIFTED THE WINDS A TAD QUICKER THAN GUIDANCE WAS SHOWING...AS
COULD SEE THIS QUICKER FLOP OVER TO THE NORTHEAST WITH THE LAKE
INFLUENCE.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE WITH VFR CONDITIONS.
* HIGH CONFIDENCE WITH WIND SPEED AND DIRECTION THROUGH EARLY
AFTERNOON...WITH MEDIUM CONFIDENCE AS TO TIMING OF WIND SHIFT
LATER IN THE AFTERNOON AND EARLY EVENING.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z...
WEDNESDAY THROUGH SUNDAY...VFR. SLIGHT CHC SHRA/TSRA WEST OF
TERMINALS SUNDAY.
RATZER
&&
.MARINE...
231 PM CDT
A LARGE LOW HAS MOVED INTO HUDSON BAY...WHILE HIGH PRESSURE SITS OFF
THE NEW ENGLAND COAST. THE UPPER LEVEL PRESSURE GRADIENT HAS
RELAXED...RESULTING IN SOUTH TO SOUTHWEST WINDS 15-25 KT ACROSS THE
LAKE THIS AFTERNOON. STRONGEST WINDS AROUND 25 KT WILL CONTINUE TO
BE OVER THE NORTHERN HALF OF THE LAKE WHICH IS CLOSER TO THE LOW AND
ITS TIGHT PRESSURE GRADIENT. THE LOWS COLD FRONT WILL SWEEP ACROSS
THE LAKE TONIGHT. WINDS WILL TURN OUT OF THE WEST AT 15 TO 25 KT
ACROSS THE LAKE BEHIND THE FRONT. HIGH PRESSURE MOVES IN BEHIND THE
FRONT TUESDAY NIGHT...WITH WINDS DIMINISHING AND BECOMING NORTHERLY
FOR A ON TUESDAY. THE LIGHT WINDS WILL CONTINUE TO VEER TO EASTERLY
AS THE HIGH MOVES OVER THE LAKE WEDNESDAY. WINDS TURN SOUTHEASTERLY
AS THE HIGH MAKES ITS WAY OVER NORTHERN QUEBEC ON THURSDAY.
ALTHOUGH THE CENTER OF THE HIGH MOVES OFF TO THE NORTHEAST...A LARGE
RIDGE WILL REMAIN OVER THE EASTERN THIRD OF THE US THROUGH THE
REMAINING PART OF THE FORECAST PERIOD. THIS PATTERN WILL RESULT IN
LIGHT WINDS VARYING BETWEEN EAST AND SOUTH.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1115 PM CDT MON JUN 11 2012
.DISCUSSION...
ISSUED 849 PM CDT MON JUN 11 2012
LATEST SURFACE ANALYSIS INDICATING THE COLD FRONT WAS LOCATED JUST
WEST OF PEORIA AND JACKSONVILLE WITH DEW POINTS SOME 15 TO 20 DEGREES
LOWER TO THE WEST OF THE FRONT EARLY THIS EVENING. EXTENSIVE CLOUD
COVER FROM THE CONVECTION WHICH OCCURRED OVER PARTS OF THE CENTRAL
AND SOUTHERN FORECAST AREA TODAY...AND LACK OF ANY SIGNIFICANT
LOW LEVEL CONVERGENCE ALONG THE FRONT HAS LED TO VERY LITTLE
REDEVELOPMENT OF STORMS THIS EVENING. THE BULK OF THE NEWLY DEVELOPED
CONVECTION HAS OCCURRED FURTHER TO THE NORTH AND EAST AND WAS MOVING
AWAY FROM OUR AREA. THE 00Z ILX SOUNDING INDICATING A FAIRLY WORKED
OVER ATMOSPHERE ACROSS CENTRAL ILLINOIS FROM THE CONVECTION OF EARLIER
TODAY WITH A SIGNIFICANT AMOUNT OF CONVECTIVE INHIBITION NOTED. THE
SLIGHT CHANCE/ISOLATED POPS HAVE BEEN REMOVED FROM THE GRIDS AND
OTHER THAN SOME MINOR TWEAKS TO THE EARLY EVENING HOURLY TEMPS...THE
REST OF THE FORECAST HAS A GOOD HANDLE ON THE OVERNIGHT TRENDS. THE
UPATED ZONE FORECAST WILL BE OUT BY 915 PM.
&&
.AVIATION...
ISSUED 1105 PM CDT MON JUN 11 2012
VFR CONDITIONS TO CONTINUE THROUGH TUESDAY NIGHT. THE COLD FRONT
CONTINUES TO MAKE SLOW PROGRESS ACRS THE STATE THIS EVENING. IT
WAS CURRENTLY ALONG THE I-55 CORRIDOR AND SHOULD TRACK EAST OF
OUR TAF SITES BY 07Z. WINDS SHOULD SWITCH INTO THE NORTHWEST
AFTR FROPA WITH SPEEDS AVERAGING FROM 5 TO 10 KTS. FORECAST
SOUNDINGS FOR TUESDAY CONTINUE TO SUGGEST MAINLY CLEAR SKIES
DURING THE DAY WITH PERHAPS A FEW CU AT TIMES WITH BASES AROUND
4500-5000 FEET. NORTHWEST WINDS OF 12 TO 17 KTS CAN BE EXPECTED
DURING THE DAY...WITH WINDS QUICKLY DIMINISHING TOWARDS EVENING.
SMITH
&&
.PREV DISCUSSION...
ISSUED 258 PM CDT MON JUN 11 2012
SHORT TERM...TONIGHT THROUGH THURSDAY
MAIN QUESTION IN THE IMMEDIATE SHORT-TERM IS WHETHER OR NOT ANY
CONVECTION WILL RE-DEVELOP ALONG AN ADVANCING COLD FRONT THIS
EVENING. 2 PM SURFACE ANALYSIS SHOWS FRONT ACROSS EASTERN
IOWA...HOWEVER AIRMASS AHEAD OF IT IS STILL QUITE STABLE DUE TO
MORNING CONVECTION THAT DECAYED ACROSS WEST-CENTRAL ILLINOIS.
LATEST MESO-ANALYSIS FROM SPC IS INDICATING SOME DESTABILIZATION
ALONG THE BOUNDARY...WITH SURFACE-BASED CAPES BACK UP TO AROUND
1500 TO 2000J/KG. 19Z VISIBLE SATELLITE IMAGERY IS SHOWING A
NARROW RIBBON OF CU DEVELOPING IN THE INSTABILITY AXIS...HOWEVER
NO SHOWERS/STORMS HAVE FIRED YET. 12Z MODELS ARE LARGELY
USELESS...AS NONE OF THEM ADEQUATELY PREDICTED THE STORMS THAT
ROLLED ACROSS SOUTH-CENTRAL AND SOUTHEAST ILLINOIS THIS AFTERNOON
ALONG THE LEADING EDGE OF AN OLD OUTFLOW BOUNDARY. EVEN SOME OF
THE HIGHER-RES MODELS SUCH AS THE 4KM WRF FAILED TO CAPTURE THIS
CONVECTION...SO THEIR SOLUTIONS FOR LATE THIS AFTERNOON AND
EVENING ARE SUSPECT. THE 17Z HRRR SEEMS TO HAVE THE BEST HANDLE ON
REALITY...SHOWING THE CURRENT CONVECTION ACROSS THE FAR E/SE KILX
CWA EXITING THE AREA OVER THE NEXT 2 TO 3 HOURS...FOLLOWED BY
LARGELY DRY CONDITIONS THIS EVENING. THE HRRR DOES TRY TO DEVELOP
SOME ISOLATED CONVECTION ALONG THE COLD FRONT AS IT PUSHES INTO
THE ILLINOIS RIVER VALLEY AROUND 00Z...BUT THIS RAPIDLY DISSIPATES
AS DAYTIME INSTABILITY IS LOST AFTER SUNSET. SINCE THE FRONT IS
STILL OFF TO THE WEST...THINK THIS SOLUTION SEEMS REASONABLE...SO
WILL MENTION ISOLATED THUNDER ACROSS THE BOARD DURING THE EARLY
EVENING. AFTER THAT...SKIES WILL CLEAR FROM WEST TO EAST ACROSS
THE AREA AS THE FRONT PUSHES INTO INDIANA AFTER MIDNIGHT.
HIGH PRESSURE WILL BUILD INTO THE GREAT LAKES FOR THE MIDDLE OF
THE WEEK...PROVIDING COOLER AND LESS HUMID CONDITIONS FOR TUESDAY
THROUGH THURSDAY. COOLEST MORNING WILL BE WEDNESDAY MORNING...WHEN
TEMPS FALL INTO THE LOWER 50S. AFTERNOON HIGHS ON WEDNESDAY WILL
BE NEAR OR SLIGHTLY BELOW NORMAL IN THE UPPER 70S/LOWER 80S.
LONG TERM...FRIDAY THROUGH MONDAY
WARMER AND MORE HUMID WEATHER WILL RETURN FOR THE EXTENDED...AS
UPPER TROUGH DIGS ACROSS THE WESTERN CONUS AND RIDGING DEVELOPS
ACROSS THE EAST. MODELS CONTINUE TO DISAGREE ON THE EXACT DEGREE
OF AMPLIFICATION WITHIN THE FLOW...WITH THE 12Z 11 JUN GFS
FEATURING A STRONG RIDGE AND RESULTING DRY CONDITIONS RIGHT
THROUGH EARLY NEXT WEEK. MEANWHILE...THE LATEST ECMWF CONTINUES TO
BE WEAKER WITH THE UPPER RIDGE AND BRINGS A FRONTAL BOUNDARY INTO
THE AREA SUNDAY INTO MONDAY. GIVEN CURRENT MODEL DISCREPANCIES
AND THE FACT THAT PARTS OF CENTRAL ILLINOIS ARE IN A MODERATE
DROUGHT...WILL MAINTAIN HOT AND DRY CONDITIONS THROUGH MONDAY.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
603 AM EDT TUE JUN 12 2012
.SHORT TERM...(TODAY)
ISSUED AT 602 AM EDT TUE JUN 12 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A FAIRLY DEEP TROF
EXTENDING FROM HUDSON BAY TO THE UPPER GREAT LAKES. ONE VORT MAX IS
MOVING ACROSS LAKE SUPERIOR/UPPER MI ATTM AND ANOTHER WEAKER VORT
MAX IS DROPPING SE INTO NRN MN. AT THE SFC...COLD FRONT HAS CLEARED
THE FCST AREA...AND STRONG CAA IS UNDERWAY. 850MB TEMPS WHICH WERE
RUNNING 10-16C AT 00Z SHOULD BE DOWN TO 0 TO 2C AT 18Z TODAY.
WITH 850MB THERMAL TROF ARRIVING BY MID DAY...EXPECT PLENTY OF CLOUD
COVER THRU THE MORNING HRS. SECONDARY SHORTWAVE BRUSHING THE AREA
MIGHT BRING A FEW -SHRA/SPRINKLES ACROSS THE N AS WELL. THERE HAVE
BEEN OCNL REPORTS OF LIGHT PCPN IN NRN MN DURING THE NIGHT. CLOUDS
SHOULD SLOWLY BEGIN TO BREAK UP FROM W TO E DURING THE AFTN. MODELS
ARE FAIRLY AGGRESSIVE WITH THE DRYING/CLEARING TREND. MIGHT BE A BIT
TOO QUICK GIVEN PROXIMITY OF THERMAL TROF DURING THE LATTER PORTION
OF THE DAY. UNDER CLOUDS/CAA...TEMPS SHOULD RISE VERY LITTLE THIS
MORNING. IN FACT...TEMPS OVER THE E MAY FALL A FEW DEGREES DURING
THE MORNING...ESPECIALLY CLOSE TO LAKE SUPERIOR. DURING THE AFTN...
TEMPS MAY NOT GET OUT OF THE UPPER 40S E OF MUNISING GIVEN CHILLY
AIR MASS AND STRONG GRADIENT FLOW ACROSS THE LAKE. ELSEWHERE...TEMPS
WILL BEGIN TO RISE DURING THE AFTN AS CLOUDS SLOWLY BEGIN TO BREAK
UP FROM W TO E. WITH EXPECTATION OF SOME SUN...UPPER 50S/LWR 60S
SHOULD GENERALLY BE THE RULE. MAY REACH THE MID 60S OVER THE SCNTRL.
COLD AIR ARRIVING TODAY WILL SET THE STAGE FOR A CHILLY/POSSIBLY
FROSTY NIGHT TONIGHT. WITH SFC HIGH PRES MOVING INTO THE VCNTY...
WINDS WILL DROP TO CALM/NEAR CALM. DRY AIR MASS (PRECIPITABLE WATER
35 TO 50PCT OF NORMAL THRU AT LEAST THE FIRST HALF OF THE NIGHT)
WILL ALLOW FOR STRONG RADIATIONAL COOLING UNDER CLEAR SKIES. RIGHT
NOW...IT APPEARS GREATEST COVERAGE OF FROST WILL BE OVER THE
INTERIOR W HALF TOWARD THE WI BORDER. HAVE THUS OPTED FOR A FROST
ADVY FOR GOGEBIC/IRON/DICKINSON LATE TONIGHT. MAY NEED TO EXPAND
ADVY EASTWARD IN LATER FCSTS SINCE LOWEST PRECIPITABLE WATER LINGERS
LONGEST OVER THE E.
.LONG TERM...(TONIGHT THROUGH MONDAY)
ISSUED AT 602 AM EDT TUE JUN 12 2012
WED MORNING WILL START WITH A SFC HIGH OVER THE CWA AND ZONAL FLOW
ALOFT. AS THE SFC HIGH CENTER MOVES TO LAKE HURON BY 00Z THU...SLY
FLOW WILL BE INCREASING THROUGH THE DAY SUNDAY. 850MB TEMPS WILL
INCREASE FROM A CWA AVG OF 4C 12Z WED TO 9C 00Z THU. WE SHOULD BE
ABLE TO MIX TO AROUND 800MB WED AFTERNOON...RESULTING IN HIGH TEMPS
IN THE MID 60S TO MID 70S AND MIN RH VALUES OF 20 TO 30 PERCENT
INTERIOR W...AND 25 TO 35 PERCENT INTERIOR E. THANKFULLY...WINDS
SHOULD BE LESS THAN 15MPH WITH GUSTS OF 20MPH OR LESS.
A SHORTWAVE TROUGH WILL MOVE E OVER LAKE WINNIPEG BY 00Z FRI...WITH
A SFC LOW BENEATH IT AND A SFC TROUGH STRETCHING INTO WRN MN. WHILE
THE SFC HIGH WILL HAVE MOVED WELL INTO QUEBEC...A SFC RIDGE WILL
REMAIN OVER THE LOWER GREAT LAKES...INCREASING THE PRESSURE GRADIENT
/AND THUS THE SLY FLOW/ OVER THE CWA. BY 00Z THU...850MB TEMPS WILL
INCREASE TO AROUND 15C...MAKING FOR HIGH TEMPS IN THE 70S TO LOW 80S
OVER MOST OF UPPER MI. WITH THE INCREASED SLY FLOW...MID LEVEL
MOISTURE WILL BE GREATER THAN ON WED...BUT MODELS SHOW A VERY DRY
LAYER AROUND 875MB...SO RH VALUES MAY FALL TO AROUND 30 PERCENT
INLAND ON THU. SOME MODELS DO TRY TO BRING IN SOME PRECIP OVER FAR
WRN UPPER MI AND WRN LAKE SUPERIOR...BUT MAJORITY OF GUIDANCE KEEPS
THE PRECIP JUST W OF THE CWA. WILL GO WITH THE DRIER IDEA GIVEN VERY
DRY LOW LEVELS AND DRY TREND AS OF LATE. GENERALLY...SFC WINDS
SHOULD BE AROUND 15MPH WITH GUSTS OF 20-25MPH THU AFTERNOON/EVENING.
THE WINNIPEG SHORTWAVE MOVES TO HUDSON BAY BY 18Z FRI...BUT THE SFC
TROUGH SHOULD STAY NW OF THE CWA THROUGH FRI. MODELS ARE IN FAIRLY
GOOD GENERAL AGREEMENT SHOWING SOME PRECIP ACROSS THE CWA FRI AS
STRONG SLY FLOW CONTINUES. WE SHOULD SEE BETTER MOISTURE...SO SOME
PRECIP IS POSSIBLE...BUT WE WILL BE LACKING A GOOD FORCING MECHANISM
SO WILL NOT GO HIGHER THAN LOW CHANCE POPS. 850MB TEMPS INCREASE A
DEGREE OR TWO FROM THU...RESULTING IN HIGH TEMPS FROM THE MID 70S TO
MID 80S...WARMEST INTERIOR W.
MODEL AGREEMENT INCREASES CONSIDERABLY FOR SAT THROUGH MON WITH THE
PASSAGE OF A SERIES OF SHORTWAVES...DECREASING FORECAST CONFIDENCE
SIGNIFICANTLY. MODELS ARE IN GENERAL AGREEMENT IN SHOWING A DEEP
UPPER TROUGH MOVING INTO THE NRN PLAINS STATES MON...BUT HOW DEEP
AND HOW FAR E THE TROUGH IS REMAINS IN QUESTION...AND THESE ASPECTS
OF THIS SYSTEM WILL PLAY A CRUCIAL ROLE FOR THE FORECAST FOR MON.
USED A CONSENSUS OF MODELS FOR THIS TIME FRAME.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 135 AM EDT TUE JUN 12 2012
GUSTY W TO NW WINDS WILL CONTINUE INTO TODAY AT KIWD/KSAW AND
ESPECIALLY AT KCMX. UPSTREAM OBS SUGGEST MVFR CIGS SHOULD DEVELOP
OVERNIGHT AT KIWD AND KCMX AND THEN IN THE MORNING AT KSAW AS COLDER
AIR SETTLES INTO THE REGION. ANY MVFR CIGS SHOULD LIFT DURING THE
AFTERNOON AS DRIER AIR MOVES IN.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 602 AM EDT TUE JUN 12 2012
STRONG PUSH OF COLDER AIR INTO THE UPPER LAKES WILL RESULT IN W TO
NW WINDS OF 20-30KT TODAY. THERE MAY BE A FEW GALE FORCE GUSTS ON
SOME OF THE HIGHEST OBSERVING PLATFORMS OVER THE E HALF OF THE LAKE
THRU THE MORNING HRS. HIGH PRES OVER THE NRN PLAINS WILL THEN ARRIVE
OVER THE WESTERN GREAT LAKES TONIGHT...RESULTING IN WINDS
DIMINISHING TO UNDER 20KT FROM W TO E LATE THIS AFTN THRU TONIGHT.
THE HIGH WILL SHIFT TO QUEBEC WED NIGHT...AND THEN FOR THE REMAINDER
OF THE WEEK...THE BASIC PATTERN WILL FEATURE A HIGH PRES RIDGE OVER
THE ERN CONUS WITH A LOW PRES TROF FROM THE WRN HIGH PLAINS TO
HUDSON BAY. A WAVE OF LOW PRES LIFTING TOWARD HUDSON BAY THU/FRI MAY
RESULT IN A PERIOD OF SOUTHERLY 15-25KT WINDS THU/THU NIGHT OVER
CNTRL LAKE SUPERIOR. OTHERWISE...WINDS WILL BE UNDER 20KT WED THRU
SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
FROST ADVISORY FROM MIDNIGHT TONIGHT TO 6 AM CDT WEDNESDAY FOR
MIZ009>011.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...JLB
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
137 AM EDT TUE JUN 12 2012
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 419 PM EDT MON JUN 11 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A FAIRLY DEEP TROF AND
ASSOC STRONG SHORTWAVE MOVING FM ND INTO NW MN. THE EASTWARD
MOVEMENT OF THIS SHORTWAVE IS HELPING TO SLOWLY PUSH A SFC COLD
FRONT ACROSS WRN UPPER MI THIS AFTERNOON. LATEST 19Z SFC
PLOT/ANALYSIS SHOWS THE FRONT IS ALONG A CRYSTAL FALLS-MICHIGAMME
LINE. ALTHOUGH 12Z MODEL SNDGS INDICATE IN EXCESS OF 1000 J/KG
MLCAPE WITH T/TD OF 82/63...VIS SATELLITE LOOP SHOWS LITTLE DVLPMT
TO CU FIELD UPSTREAM OVER CENTRAL UPPER MI OR IMMEDIATELY UPSTREAM
OVER NRN WI. SUSPECT THAT DRY ALOFT MOVING IN AHEAD OF THE SHORTWAVE
AS NOTED ON VERY DRY 12Z KMPX SNDGS MAY BE INHIBITING CU DVLPMT OVER
THE FCST AREA.
TONIGHT...GIVEN LACK OF CU DVLPMT ON VIS SATELLITE MAY END UP
EVENTUALLY HAVING TO BACK OFF ON POPS TO SLIGHT CHC OVER CENTRAL AND
ERN COUNTIES FOR THIS EVENING AHEAD OF APPROACHING FRONT. IF SOME
CONVECTION IS ABLE TO FIRE ALONG THE FRONT...THERE IS A CHANCE FOR
AN ISOLATED STRONG TO SVR STORM GIVEN THE INSTABILITY AND DEEP LAYER
SHEAR GREATER THAN 40 KTS OVER THE AREA. RELUCTANT TO PULL POPS OUT
COMPLETELY SINCE FRONT IS STILL APPROACHING BUT CHC OF PCPN IS
LOOKING MORE AND MORE DOUBTFUL THIS EVENING OVER CENTRAL AND ERN
CWA. MODEL SNDGS INDICATE WEST WINDS ARE EXPECTED TO PICK UP BEHIND
THE FRONT THIS EVENING ESPECIALLY OVER THE KEWEENAW PENINSULA WHERE
PASSAGE OF SECONDARY COLD FRONT AND INCREASING MIXING/INSTABILITY
WITH COLDER AIR COMING IN MAY PRODUCE GUSTS TO 40 MPH. LOOK FOR LOWS
TO REACH INTO THE MID 40S WEST TO MID 50S SOUTH CENTRAL AND EAST.
TUESDAY...THE 500MB TROUGH AXIS WILL MOVE ACROSS THE AREA MIDDAY
ALONG WITH THE 8H THERMAL TROF AS 850 MB TEMPS LOWER TO AROUND 0C.
WITH GOOD CAA IN THE WNW FLOW OVER THE AREA. WITH LIMITED MIXING
ALONG THE LAKE SUPERIOR SHORE EXPECT HIGHS IN THE LOWER TO MID 50S
WHILE DEEPER SOUTH CENTRAL WILL YIELD HIGHS IN THE LOWER TO MID 60S.
INCREASINGLY ANTICYCLONIC SFC-850 MB FLOW AND RDGG BUILDING IN FROM
THE WEST SHOULD SCOUR OUT LOW CLOUDS FROM WEST TO EAST IN THE
AFTERNOON.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 419 PM EDT MON JUN 11 2012
THE SFC HIGH SHOULD BE DIRECTLY OVERHEAD FROM 00-06Z
WEDNESDAY...BEFORE SHIFTING OFF TO QUEBEC WEDNESDAY AFTERNOON INTO
THURSDAY. SIMILAR TO A FEW DAYS AGO...WE WILL MONITOR THE
DEVELOPMENT OF AN ELONGATED SFC LOW STRETCHING FROM S CENTRAL CANADA
THROUGH THE CO ROCKIES.
FROST WILL REMAIN POSSIBLE TUESDAY NIGHT/WEDNESDAY MORNING...WITH
TEMPS BOTTOMING OUT 31-36F INLAND FROM THE GREAT LAKES AS WINDS GO
NEARLY CALM AND CLOUDS DISSIPATE.
WEDNESDAY WILL LIKELY BE A BIT DRIER THAN ORIGINALLY THROUGH...WITH
MIXED DEW POINTS IN THE MID 20S BY 18Z. THIS SCENARIO WOULD RESULT
IN MIN RH VALUES NEAR 20 PERCENT OVER THE WEST HALF OF UPPER
MI...AND 25-30 PERCENT EAST. EXPECT THE RETURN OF LIGHT/SOUTHERLY
FLOW AS THE HIGH SHIFTS ACROSS LAKE HURON AND STRETCHES THROUGH
QUEBEC...STILL BELOW 15MPH. DID PUSH THE FCST CLOSER TO THESE LOWEST
VALUES.
THE ELONGATED SFC LOW STRETCHING FROM SOUTHERN SASKATCHEWAN/MANITOBA
THROUGH THE DAKOTAS AND E CO/NM THURSDAY MORNING WILL CONTINUE TO
REMAIN NEARLY STEADY. ALTHOUGH THURSDAY SHOULD BE WARMER...WITH
INCREASED SOUTHERLY WINDS /20-35KTS BETWEEN THE SFC AND
850MB/...MOISTURE SHOULD BE ON THE INCREASE AS WELL. MIN RH VALUES
COULD STILL NEAR 30 PERCENT OVER PORTIONS OF INTERIOR W UPPER MI BY
LATE MORNING/EARLY AFTERNOON.
THE FCST FOR SUNDAY MONDAY REMAINS VERY UNCERTAIN...SO DID NOT GO
TOO FAR IN DEPTH WITH ADJUSTMENTS FOR THAT PERIOD. THE WESTERN SFC
LOW WILL BE LOCATED SOMEWHERE BETWEEN NWS ONTARIO AND MN BY 12Z
MONDAY...WITH THE TRAILING COLD FRONT STILL REMAINING TO OUR W BY
THE END OF THE DAY. THE RESULT SHOULD BE ANOTHER ROUND OF WARM/HOT
WEATHER SATURDAY THROUGH MONDAY...AS S WINDS REMAIN STEADY AND 850MB
TEMPS RISE AGAIN TO 16 TO 20C.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 135 AM EDT TUE JUN 12 2012
GUSTY W TO NW WINDS WILL CONTINUE INTO TODAY AT KIWD/KSAW AND
ESPECIALLY AT KCMX. UPSTREAM OBS SUGGEST MVFR CIGS SHOULD DEVELOP
OVERNIGHT AT KIWD AND KCMX AND THEN IN THE MORNING AT KSAW AS COLDER
AIR SETTLES INTO THE REGION. ANY MVFR CIGS SHOULD LIFT DURING THE
AFTERNOON AS DRIER AIR MOVES IN.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 419 PM EDT MON JUN 11 2012
LOW PRESSURE ACROSS HUDSON BAY WILL KEEP A TROUGH ACROSS LS THIS
EVENING...AHEAD OF HIGH NEARING FROM THE WEST. EXPECT THE HIGH OVER
MINNESOTA TUESDAY MORNING TO PUSH ACROSS THE UPPER GREAT LAKES
TUESDAY AFTERNOON THROUGH WEDNESDAY...BEFORE EXITING ACROSS QUEBEC
WEDNESDAY NIGHT. W-NW GUSTS OF 30 TO POSSIBLY 30KTS WILL SLIDE IN
OVERNIGHT AND LINGER THROUGH THE DAY TUESDAY. A RIDGE WILL REMAIN
ACROSS LS THROUGH SATURDAY...AS AN ELONGATED AREA OF LOW PRESSURE
ORGANIZES ACROSS THE CENTRAL AND NORTHERN PLAINS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...KF
AVIATION...JLB
MARINE...KF
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
510 AM EDT TUE JUN 12 2012
.SYNOPSIS...
A COLD FRONT WILL SWEEP WEST TO EAST ACROSS THE REGION TODAY. A MUCH
DRIER AIR MASS WILL BEGIN TO BUILD ACROSS THE SOUTHERN APPALACHIAN
REGION TONIGHT. SURFACE HIGH PRESSURE IS EXPECTED TO REMAIN OVER THE
WESTERN CAROLINAS AND NORTHEAST GEORGIA INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 510 AM TUESDAY...ISOLATED SHRA ARE AFFECTING MOST OF THE FA
ATTM. AREAS OF DRIZZLE HAVE ALSO STARTED TO DEVELOP PER LOWERING
VSBYS ON SOME REGION ASOS AND AWOS STATIONS. DRIZZLE HAS BEEN ADDED
TO THE ZONES FOR ALL FOOTHILL AND PIEDMONT LOCATIONS THROUGH 12 UTC
AS LOW CLOUDS AND WEAK LLVL ISENTROPIC UPGLIDE WILL CONTINUE THROUGH
THIS TIME. POPS HAVE ALSO BEEN RAISED A LITTLE ALONG THE TN LINE. A
WEAK MCV WILL APPROACH FROM THE WEST. IT HAS TRIGGERED SHOWERS OVER
ERN TN AND THEY SHOULD BEGIN TO AFFECT THE WRN NC MTNS WITHIN THE
NEXT 1 TO 2 HOURS.
PREVIOUS DISCUSSION...
THE LATEST RUN OF THE RAP HAD A CONVECTIVELY INDUCED H5 SHORT WAVE
OVER ERN TN. IT DROPS THIS FEATURE SOUTHEASTWARD DURING THE COURSE
OF THE MORNING...AND BY EARLY AFTN IT/S LOCATED OVER SOUTH CENTRAL
GA. THE GFS MAINTAINS A STRONGER SHORT WAVE OVER THE WRN
CAROLINAS... WHILE THE NAM IS NOT A STRONG WITH THE WAVE.
OVERALL...THE GFS MAY BE OVERDONE WITH THIS FEATURE. THE GFS BUFKIT
SOUNDINGS LOOK MODESTLY IMPRESSIVE THIS AFTN WITH CAPE VALUES
RANGING FROM 1200-1500 J/KG AND LITTLE IF ANY INHIBITION. THE NAM
STILL HAS PLENTY OF INSTABILITY...BUT IT MAINTAINS MORE CAPPING IN
THE LOW LEVELS. I STILL PLAN TO CARRY LOW END LIKELY POPS ACROSS
MOST OF THE FA...AND IN PARTICULAR THE I-77 CORRIDOR...BUT THE
RECENT SOUTHWARD SHIFT OF THE SHORT WAVE DOES NOT BODE AS WELL FOR
EXTENSIVE CONVECTIVE COVERAGE. WITH MORE DRYING ALOFT...THERE IS A
CHANCE FOR A FEW DAMAGING DOWNBURSTS TODAY. IN FACT...THE NAM SFC
DELTA THETA-E VALUES ARE IN THE MID 20S WHICH WOULD CERTAINLY
SUPPORT DAMAGING WINDS WITH THE STRONGER STORMS THIS AFTERNOON.
A COLD FRONT WILL CROSS THE REGION OVERNIGHT. I HAVE CONVECTION
ENDING FAIRLY QUICKLY THIS EVENING AS THE SOUNDINGS SHOW
CONSIDERABLE LOW LEVEL INHIBITION EVEN WITH THE BNDRY PUSHING ACROSS
THE REGION.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
AS OF 220 AM TUESDAY...BY DAYBREAK WEDNESDAY....THE COLD FRONT WILL
SLIDE EAST OFF THE CAROLINA COAST AS HIGH PRESSURE BUILDS ACROSS THE
GREAT LAKES AREA. A BLEND OF THE GFS AND ECMWF INDICATES THAT THE
CWA WILL REMAIN ON THE SOUTHERN EDGE OF SFC HIGH PRESSURE WEDNESDAY
AND THURSDAY. IN THE MID LEVELS...THE EARLY PHASE OF AN OMEGA BLOCK
WILL DEVELOP ACROSS THE CONUS...WITH RIDGING BUILDING NORTH ACROSS
THE MISSISSIPPI AND OHIO RIVER VALLEYS. BOTH SOLUTIONS INDICATE THAT
A SHALLOW POOL OF MOISTURE AND WEAK INSTABILITY WILL REMAIN ACROSS
THE NC MTNS WEDNESDAY AND THURSDAY. I WILL CONTINUE TO INDICATE
DIURNAL SCHC POPS ACROSS THE MTNS...ISO ACROSS THE FOOTHILLS AND
PIEDMONT. HIGH TEMPERATURES MAY RANGE FROM L80S ACROSS THE MTN
VALLEYS TO THE U80S TO AROUND 90 DEGREES EAST OF I-85 ON WEDNESDAY.
HIGH TEMPERATURES ON THURSDAY MAY REMAIN AROUND 1 TO 2 DEGREES
COOLER THAN WEDNESDAY. LOWS WEDNESDAY NIGHT ARE FORECAST TO RANGE
FROM U50S ACROSS THE MTNS TO MID 60S EAST.
&&
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
AS OF 230 AM TUESDAY...FRIDAY THROUGH MONDAY...THE MID LEVEL PATTERN
WILL REMAIN SOLIDLY BLOCK THROUGH MOST OF THE PERIOD...BEGINNING TO
WEAKEN EARLY NEXT WEEK. THE MAIN MID LEVEL FEATURES WILL REMAIN THE
RIDGE CENTER ACROSS THE MID WEST WITH LOW PRESSURE OVER THE WESTERN
ATLANTIC. AT THE SFC...HIGH PRESSURE WILL REMAIN CENTERED OVER NEW
ENGLAND WITH RIDGING EXTENDING SW ACROSS THE CWA. GFS FORECAST
SOUNDINGS INDICATES THAT WEAK INSTABILITY AND WEAK LLVL CIN WILL
EXIST ACROSS THE MTNS EACH AFTERNOON AND EVENING. I WILL MAINTAIN
DIURNAL SCHC ACROSS THE MTNS FOR SHRA AND TSRA. TEMPERATURES EACH
DAY SHOULD CHANGE VERY LITTLE FROM DAY TO DAY...RANGING FROM U70S
ACROSS THE MTN VALLEYS TO MID 80S EAST. LOW TEMPERATURES ARE
FORECAST TO RANGE FROM U50S ACROSS THE MTN VALLEYS TO L60S EAST.
&&
.AVIATION /09Z TUESDAY THROUGH SATURDAY/...
AT KCLT...A VERY MOIST AIRMASS AND INCREASING SOUTHWEST WINDS IN THE
BNDRY LAYER HAVE RESULTED IN WIDESPREAD IFR TO LIFR CIGS ACROSS THE
REGION. CIGS SHOULD HOLD BETWEEN 400 AND 600 FEET THROUGH MID
MORNING BEFORE MIXING INTO A VFR CU FIELD IN THE AFTN. SCT SHRA ARE
DEVELOPING WEST OF THE AIRFIELD. WITH LIMITED INSTABILITY I DIDN/T
THINK THE SHRA WOULD MAKE IT TO KCLT...BUT IF THE INCREASING TREND
CONTINUES...SOME SHRA WILL BE ADDED TO THE TAF. AN UPPER LOW WILL
CROSS THE REGION THIS AFTN...KICKING OFF NUMEROUS SHRA/TSTMS ONCE
AGAIN...LASTING INTO THE EARLY EVENING HOURS. PROB30 HAS BEEN
INCLUDED TO ACCOUNT FOR THIS.
ELSEWHERE...LIKE AT KCLT...SOUTHWEST WINDS AND A VERY MOIST AIRMASS
HAS RESULTED IN WIDESPREAD STRATUS CIGS WHICH HAVE GENERALLY SETTLED
INTO THE 400 TO 600 FOOT RANGE. THESE GENERAL CONDITIONS SHOULD
CONTINUE THROUGH MID MORNING. HOWEVER...AREAS OF FOG AND POSSIBLY
EVEN LOWER CIGS ARE EXPECTED TO DEVELOP AT KAVL AND KHKY WHERE THE
WINDS WILL BE LIGHTER. LIGHT SHRA CONTINUE TO DEVELOP IN THE MOIST
AIRMASS NEAR THE MTNS...AND LIGHT RAIN HAS BEEN CARRIED AT
KGSP...KGMU AND KHKY MOST OF THE NIGHT WHERE THE LIGHT RAIN AND
DRIZZLE SHOULD CONTINUE FOR SEVERAL MORE HOURS. CIGS WILL MIX INTO A
VFR CU FIELD IN THE AFTN. NUMEROUS SHRA/TSTMS WILL DEVELOP AGAIN AS
AN UPPER LOW CROSSES THE REGION. THE MOST LIKELY PERIOD FOR TSTMS IS
IN THE EARLY TO MID AFTN HOURS.
OUTLOOK...GENERALLY DRY CONDITIONS ARE NOW EXPECTED BEHIND A COLD
FRONT WEDNESDAY THROUGH FRIDAY. HOWEVER...ISOLATED AFTERNOON TSTMS
WILL DEVELOP OVER THE MTNS EACH DAY...WHICH COULD HAVE SOME AFFECT
ON OPERATIONS AT KAVL.
AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE
PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE
CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)...
WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...NED
NEAR TERM...MCAVOY
SHORT TERM...NED
LONG TERM...NED
AVIATION...MCAVOY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
325 AM EDT TUE JUN 12 2012
.SYNOPSIS...
A COLD FRONT WILL SWEEP WEST TO EAST ACROSS THE REGION TODAY. A MUCH
DRIER AIR MASS WILL BEGIN TO BUILD ACROSS THE SOUTHERN APPALACHIAN
REGION TONIGHT. SURFACE HIGH PRESSURE IS EXPECTED TO REMAIN OVER THE
WESTERN CAROLINAS AND NORTHEAST GEORGIA INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE LATEST RUN OF THE RAP HAD A CONVECTIVELY INDUCED H5 SHORT WAVE
OVER ERN TN. IT DROPS THIS FEATURE SOUTHEASTWARD DURING THE COURSE
OF THE MORNING...AND BY EARLY AFTN IT/S LOCATED OVER SOUTH CENTRAL
GA. THE GFS MAINTAINS A STRONGER SHORT WAVE OVER THE WRN
CAROLINAS... WHILE THE NAM IS NOT A STRONG WITH THE WAVE.
OVERALL...THE GFS MAY BE OVERDONE WITH THIS FEATURE. THE GFS BUFKIT
SOUNDINGS LOOK MODESTLY IMPRESSIVE THIS AFTN WITH CAPE VALUES
RANGING FROM 1200-1500 J/KG AND LITTLE IF ANY INHIBITION. THE NAM
STILL HAS PLENTY OF INSTABILITY...BUT IT MAINTAINS MORE CAPPING IN
THE LOW LEVELS. I STILL PLAN TO CARRY LOW END LIKELY POPS ACROSS
MOST OF THE FA...AND IN PARTICULAR THE I-77 CORRIDOR...BUT THE
RECENT SOUTHWARD SHIFT OF THE SHORT WAVE DOES NOT BODE AS WELL FOR
EXTENSIVE CONVECTIVE COVERAGE. WITH MORE DRYING ALOFT...THERE IS A
CHANCE FOR A FEW DAMAGING DOWNBURSTS TODAY. IN FACT...THE NAM SFC
DELTA THETA-E VALUES ARE IN THE MID 20S WHICH WOULD CERTAINLY
SUPPORT DAMAGING WINDS WITH THE STRONGER STORMS THIS AFTERNOON.
A COLD FRONT WILL CROSS THE REGION OVERNIGHT. I HAVE CONVECTION
ENDING FAIRLY QUICKLY THIS EVENING AS THE SOUNDINGS SHOW
CONSIDERABLE LOW LEVEL INHIBITION EVEN WITH THE BNDRY PUSHING ACROSS
THE REGION.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
AS OF 220 AM TUESDAY...BY DAYBREAK WEDNESDAY....THE COLD FRONT WILL
SLIDE EAST OFF THE CAROLINA COAST AS HIGH PRESSURE BUILDS ACROSS THE
GREAT LAKES AREA. A BLEND OF THE GFS AND ECMWF INDICATES THAT THE
CWA WILL REMAIN ON THE SOUTHERN EDGE OF SFC HIGH PRESSURE WEDNESDAY
AND THURSDAY. IN THE MID LEVELS...THE EARLY PHASE OF AN OMEGA BLOCK
WILL DEVELOP ACROSS THE CONUS...WITH RIDGING BUILDING NORTH ACROSS
THE MISSISSIPPI AND OHIO RIVER VALLEYS. BOTH SOLUTIONS INDICATE THAT
A SHALLOW POOL OF MOISTURE AND WEAK INSTABILITY WILL REMAIN ACROSS
THE NC MTNS WEDNESDAY AND THURSDAY. I WILL CONTINUE TO INDICATE
DIURNAL SCHC POPS ACROSS THE MTNS...ISO ACROSS THE FOOTHILLS AND
PIEDMONT. HIGH TEMPERATURES MAY RANGE FROM L80S ACROSS THE MTN
VALLEYS TO THE U80S TO AROUND 90 DEGREES EAST OF I-85 ON WEDNESDAY.
HIGH TEMPERATURES ON THURSDAY MAY REMAIN AROUND 1 TO 2 DEGREES
COOLER THAN WEDNESDAY. LOWS WEDNESDAY NIGHT ARE FORECAST TO RANGE
FROM U50S ACROSS THE MTNS TO MID 60S EAST.
&&
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
AS OF 230 AM TUESDAY...FRIDAY THROUGH MONDAY...THE MID LEVEL PATTERN
WILL REMAIN SOLIDLY BLOCK THROUGH MOST OF THE PERIOD...BEGINNING TO
WEAKEN EARLY NEXT WEEK. THE MAIN MID LEVEL FEATURES WILL REMAIN THE
RIDGE CENTER ACROSS THE MID WEST WITH LOW PRESSURE OVER THE WESTERN
ATLANTIC. AT THE SFC...HIGH PRESSURE WILL REMAIN CENTERED OVER NEW
ENGLAND WITH RIDGING EXTENDING SW ACROSS THE CWA. GFS FORECAST
SOUNDINGS INDICATES THAT WEAK INSTABILITY AND WEAK LLVL CIN WILL
EXIST ACROSS THE MTNS EACH AFTERNOON AND EVENING. I WILL MAINTAIN
DIURNAL SCHC ACROSS THE MTNS FOR SHRA AND TSRA. TEMPERATURES EACH
DAY SHOULD CHANGE VERY LITTLE FROM DAY TO DAY...RANGING FROM U70S
ACROSS THE MTN VALLEYS TO MID 80S EAST. LOW TEMPERATURES ARE
FORECAST TO RANGE FROM U50S ACROSS THE MTN VALLEYS TO L60S EAST.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
AT KCLT...A VERY MOIST AIRMASS AND INCREASING SOUTHWEST WINDS IN THE
BNDRY LAYER HAVE RESULTED IN WIDESPREAD IFR TO LIFR CIGS ACROSS THE
REGION. CIGS SHOULD HOLD BETWEEN 400 AND 600 FEET THROUGH MID
MORNING BEFORE MIXING INTO A VFR CU FIELD IN THE AFTN. SCT SHRA ARE
DEVELOPING WEST OF THE AIRFIELD. WITH LIMITED INSTABILITY I DIDN/T
THINK THE SHRA WOULD MAKE IT TO KCLT...BUT IF THE INCREASING TREND
CONTINUES...SOME SHRA WILL BE ADDED TO THE TAF. AN UPPER LOW WILL
CROSS THE REGION THIS AFTN...KICKING OFF NUMEROUS SHRA/TSTMS ONCE
AGAIN...LASTING INTO THE EARLY EVENING HOURS. PROB30 HAS BEEN
INCLUDED TO ACCOUNT FOR THIS.
ELSEWHERE...LIKE AT KCLT...SOUTHWEST WINDS AND A VERY MOIST AIRMASS
HAS RESULTED IN WIDESPREAD STRATUS CIGS WHICH HAVE GENERALLY SETTLED
INTO THE 400 TO 600 FOOT RANGE. THESE GENERAL CONDITIONS SHOULD
CONTINUE THROUGH MID MORNING. HOWEVER...AREAS OF FOG AND POSSIBLY
EVEN LOWER CIGS ARE EXPECTED TO DEVELOP AT KAVL AND KHKY WHERE THE
WINDS WILL BE LIGHTER. LIGHT SHRA CONTINUE TO DEVELOP IN THE MOIST
AIRMASS NEAR THE MTNS...AND LIGHT RAIN HAS BEEN CARRIED AT
KGSP...KGMU AND KHKY MOST OF THE NIGHT WHERE THE LIGHT RAIN AND
DRIZZLE SHOULD CONTINUE FOR SEVERAL MORE HOURS. CIGS WILL MIX INTO A
VFR CU FIELD IN THE AFTN. NUMEROUS SHRA/TSTMS WILL DEVELOP AGAIN AS
AN UPPER LOW CROSSES THE REGION. THE MOST LIKELY PERIOD FOR TSTMS IS
IN THE EARLY TO MID AFTN HOURS.
OUTLOOK...GENERALLY DRY CONDITIONS ARE NOW EXPECTED BEHIND A COLD
FRONT WEDNESDAY THROUGH FRIDAY. HOWEVER...ISOLATED AFTERNOON TSTMS
WILL DEVELOP OVER THE MTNS EACH DAY...WHICH COULD HAVE SOME AFFECT
ON OPERATIONS AT KAVL.
AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE
PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE
CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)...
WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...NED
NEAR TERM...MCAVOY
SHORT TERM...NED
LONG TERM...NED
AVIATION...MCAVOY
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
300 AM CDT TUE JUN 12 2012
.DISCUSSION...
A COLD FRONT CURRENTLY STRETCHES FROM NEAR MOUNT VERNON ILLINOIS TO
NEAR LITTLE ROCK ARKANSAS. CONVECTION THAT OCCURRED EARLIER THIS
EVENING HAS PUSHED ALL THE WAY TO THE GULF COAST. SOME
REDEVELOPMENT IS OCCURRING ACROSS SOUTHERN ARKANSAS IN RESPONSE TO
A SHORTWAVE. THE MOVEMENT OF THESE STORMS ARE TO THE SOUTHEAST
WHICH MOVES THEM INTO PHILLIPS COUNTY ARKANSAS AND PORTIONS OF
NORTHWEST MISSISSIPPI. MODELS INDICATE FURTHER DEVELOPMENT COULD
OCCUR TODAY ALONG AND AHEAD OF THE FRONT. HOWEVER THERE IS SOME
QUESTION ON HOW WORKED OVER THE ATMOSPHERE IS FROM THIS EVENINGS
CONVECTION. THE AREA WILL NOT BE AS UNSTABLE TODAY AS YESTERDAY
AHEAD OF THE FRONT. THE 00Z NAM INDICATES SOME REDEVELOPMENT COULD
OCCUR THIS MORNING ACROSS NORTH MISSISSIPPI BUT SHOULD PUSH SOUTH
OF THE CWA BY EARLY AFTERNOON. THE LATEST RUC AND HRRR RUN SHOWS
SOMETHING SIMILAR TO THE NAM. THE 00Z GFS DID NOT INITIALIZE WELL
WITH WHAT IS CURRENTLY GOING THUS WILL NOT BE USED IN THE SHORT
TERM. THUS WILL LOWER CHANCES FOR SHOWERS AND THUNDERSTORMS TO 40
PERCENT ACROSS MUCH OF NORTH MISSISSIPPI FOR MAINLY THIS MORNING
WITH POSSIBLY LEAVING LIKELY POPS ACROSS PHILLIPS COUNTY AND
PORTIONS OF NORTHWEST MISSISSIPPI THROUGH 7 AM. ELSEWHERE...WILL
REMOVE MENTION OF PRECIPITATION. DRIER AIR WILL BEGIN TO FILTER
INTO NORTHERN PORTIONS OF THE CWA BY THIS AFTERNOON. HIGHS WILL BE
IN THE UPPER 80S.
TONIGHT THROUGH THURSDAY NIGHT...HIGH PRESSURE WILL BUILD INTO THE
AREA FROM THE OHIO VALLEY. DRIER AIR WILL FILTER INTO THE AREA BUT
DO NOT EXPECT MUCH CHANGE IN AT LEAST HIGH TEMPERATURES. HIGHS WILL
STILL BE IN THE MID 80S TO AROUND 90 THROUGH THE PERIOD. LOWS WILL
BE COOLER WITH READINGS IN THE MID 50S TO MID 60S...POSSIBLY A TAD
WARMER THURSDAY NIGHT AS WINDS TURN AROUND TO THE SOUTH.
FRIDAY THROUGH EARLY NEXT WEEK...UPPER RIDGE MOVES OVER THE
MIDSOUTH. 00Z GFS INDICATES DIURNAL HEATING COULD KICK OFF ISOLATED
SHOWERS AND THUNDERSTORMS FRIDAY INTO THE WEEKEND. 00Z ECMWF
SHOWS SOMETHING SIMILAR. FRIDAY SEEMS A LITTLE EARLY FOR MOISTURE
RETURN TO BE ENOUGH TO CAUSE DIURNAL CONVECTION THUS WILL REMOVE POPS.
OTHERWISE...WILL LEAVE CURRENT FORECAST AS IS.
KRM
&&
.AVIATION...
06Z TAF SET
VFR CONDITIONS WILL DOMINATE...HOWEVER...SOME LOCATIONS MAY HAVE
SOME FOG IN THE MORNING. IF ANY FOG DOES DEVELOP EXPECT IT TO BE
MVFR CONDITIONS. WINDS LIGHT AND WILL SWITCH TO NORTH BY MORNING IN
ENTIRE REGION. AFTERNOON THUNDERSTORMS ARE TUESDAY ARE
POSSIBLE...HOWEVER NOT CONFIDENT ENOUGH WITH TIMING OR LOCATION AS
STORMS WILL BE AT BEST SCATTERED.
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 88 65 86 66 / 20 10 0 0
MKL 88 59 84 57 / 10 10 0 0
JBR 89 61 86 61 / 10 10 0 0
TUP 87 63 87 62 / 40 10 10 10
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1235 AM CDT TUE JUN 12 2012
.UPDATE...AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 1043 PM CDT MON JUN 11 2012/
EARLIER FORECAST IS BASICALLY ON TRACK...ALTHOUGH DID UPDATE TO
ADJUST POPS SLIGHTLY BASED ON THE LATEST HRRR MODEL. INCREASED THE
POPS SLIGHTLY FOR TONIGHT MAINLY FROM EAST CENTRAL AR INTO
NORTHWEST MS AND LOWERED THEM SLIGHTLY MOST OTHER LOCATIONS.
THUNDERSTORMS ASSOCIATED WITH THE MESOSCALE CONVECTIVE SYSTEM THAT
PLOWED THROUGH THE MIDSOUTH EARLIER TODAY NOW STRETCH FROM
NORTHERN LA ACROSS CENTRAL MS INTO CENTRAL AL. THE ATMOSPHERE
ACROSS THE MIDSOUTH IS RAIN COOLED WITH SURFACE BASED INSTABILITY
NIL. HOWEVER...ELEVATED INSTABILITY OF ABOUT 1500 TO 2000 J/KG
EXIST TO OUR WEST AND SOUTHWEST WITH 00Z 850 MB ANALYSIS SHOWING A
SOUTHWEST LY LOW LEVEL FLOW. SCATTERED SHOWERS AND THUNDERSTORMS
HAVE ALREADY BEGUN TO FORM IN CENTRAL AR. THE HRRR MODEL INDICATES
THUNDERSTORMS WILL CONTINUE TO INCREASE THROUGH THIS AREA
(POSSIBLY DEVELOPING INTO A MESOSCALE CONVECTIVE SYSTEM) AND
SLIDE TO THE SOUTHEAST SKIRTING EAST-CENTRAL AR AND NORTHWEST MS.
A FEW STRONG ELEVATED THUNDERSTORMS STILL WITH WIND GUSTS UP TO 45
MPH AND SMALL HAIL STILL LOOK POSSIBLE MAINLY FROM EAST CENTRAL
AR INTO PORTIONS OF NORTH MS. OTHERWISE A COLD FRONT WILL MOVE
INTO NORTHEAST AR AND THE MO BOOTHEEL BY LATE TONIGHT...A FEW
SHOWERS AND THUNDERSTORMS MAY DEVELOP ALONG AND AHEAD OF THE FRONT
LATER TONIGHT.
TEMPERATURES HAVE COOLED INTO THE MIDDLE 60S ACROSS MUCH OF THE
MIDSOUTH. READINGS MAY DROP A DEGREE OR TWO MORE BUT MAINLY WILL
REMAIN STEADY.
JCL
PREV DISCUSSION... /ISSUED 711 PM CDT MON JUN 11 2012/
UPDATED TO LOWER POPS ACROSS THE MID SOUTH FOR THIS EVENING AND
CLEAR SEVERE THUNDERSTORM WATCH #373 FOR THE ENTIRE AREA.
THE SEVERE LINE OF THUNDERSTORMS THAT MOVES SOUTH ACROSS THE AREA
THIS AFTERNOON AND EVENING HAS NOW EXITED OUR AREA. STRATIFORM
RAIN BEHIND THE SEVERE CONVECTION WILL PERSIST FOR A FEW HOURS AT
MOST AND MAINTAINED LIKELY POPS OVER NORTH MISSISSIPPI TO ACCOUNT
FOR THIS. ELSEWHERE HAVE LOWERED POPS FOR THIS EVENING.
LATER TONIGHT...LATEST HIGH RESOLUTION RAPID REFRESH MODEL
INDICATES ADDITIONAL DEVELOPMENT OF CONVECTION OVER WESTERN
ARKANSAS ALONG STALLED OUTFLOW BOUNDARY. THIS CONVECTION MAY MOVE
BACK OVER SOUTHERN PORTIONS OF THE FORECAST AREA AFTER MIDNIGHT.
THE CURRENT FORECAST HAD ACCOUNTED FOR THIS ACTIVITY BUT
CONFIDENCE IS RATHER LOW. THE ATMOSPHERE MAY BE TOO WORKED OVER
FROM THIS EVENINGS CONVECTION OR NEW CONVECTION MAY BE ELEVATED
OVER THE DECAYING COLD POOL. LATER UPDATES MAY BE NEEDED AS THE
EVENTUAL EVOLUTION BECOMES MORE CLEAR.
UPDATED ZONES...GRIDS...AND HWO HAVE BEEN SENT.
JLH
PREV DISCUSSION... /ISSUED 320 PM CDT MON JUN 11 2012/
A SEVERE FORWARD PROPAGATING MESOSCALE CONVECTIVE SYSTEM (MCS)
CURRENTLY ACROSS NORTHWEST TENNESSEE INTO EASTERN ARKANSAS WILL
CONTINUE TO RACE SOUTHEASTWARD THROUGH THE REMAINDER OF THE
AFTERNOON AND EVENING HOURS. THIS LINE HAS HAD A HISTORY OF WIND
DAMAGE AND THE PRE-CONVECTIVE ENVIRONMENT REMAIN FAVORABLE FOR
CONTINUED WIND DAMAGE WITH MLCAPES IN EXCESS OF 4000 J/KG. THIS
MCS CONTINUES TO MOVE ALONG THE NORTHEAST PERIPHERY OF STRONGER
CAPPING/EML OVER THE ARKLATEX REGION. THIS LINE OF SEVERE
THUNDERSTORMS SHOULD MOVE THROUGH THE REMAINDER OF THE FORECAST
AREA THROUGH THE EVENING.
LATER TONIGHT...THE FORECAST BECOMES MORE UNCERTAIN AS THE
ATMOSPHERE WILL INITIALLY BE WORKED OVER FROM THIS AFTERNOONS MCS.
THE CONVECTIVE OUTFLOW BOUNDARY SLOWS QUITE A BIT ACROSS NORTH-
CENTRAL ARKANSAS AND THIS AREA MAY BE PRIMED FOR REDEVELOPMENT
LATER THIS EVENING...WITH THE ATMOSPHERE POTENTIALLY RELOADING
ACROSS SOUTHWESTERN PORTIONS OF THE AREA. LATEST MODEL GUIDANCE
HINTS AT THIS OCCURRENCE...BUT TIMING CONTINUES TO BE A PROBLEM AS
LATEST HRRR IS FASTER WITH MOST CONVECTION PRIOR TO 06Z AND ALL
OTHER MODEL GUIDANCE NOW SLOWER AND LINGERING CONVECTION THROUGH
THE NIGHT OVER THESE LOCATIONS. PLAN TO CARRY LIKELY POPS OVER THE
SOUTH AND WEST AFTER 06Z AND WILL MAINTAIN A SEVERE THREAT FOR
DAMAGING WINDS AND LARGE HAIL.
OVERNIGHT ACTIVITY SHOULD WANE LATE TONIGHT WITH SCATTERED
THUNDERSTORM REDEVELOPMENT POSSIBLE ALONG A SOUTHWARD MOVING COLD
FRONT ALONG THE I-40 CORRIDOR BY MID MORNING. THIS FRONT WILL
CONTINUE TO DROP SOUTH THROUGH EASTERN ARKANSAS AND NORTHERN
MISSISSIPPI BY AFTERNOON WITH THUNDERSTORM ACTIVITY BECOMING MORE
NUMEROUS IN COVERAGE. THE ATMOSPHERE WILL AGAIN DESTABILIZE OVER
THE SOUTHERN HALF OF THE AREA WITH STRONG TO POTENTIALLY SEVERE
STORMS AGAIN POSSIBLE.
THE COLD FRONT WILL MOVE THROUGH THE MID SOUTH BY TUESDAY NIGHT
WITH SURFACE HIGH PRESSURE BUILDING OVER THE AREA. THE FRONT
SHOULD STALL ACROSS CENTRAL MISSISSIPPI AS UPPER LEVEL HEIGHTS
RISE. DRY AND VERY WARM WEATHER CAN BE EXPECTED WEDNESDAY THROUGH
FRIDAY MORNING. THE FRONT WILL RETURN BACK TO THE NORTH AS A WARM
FRONT BY FRIDAY ALLOWING FOR A DEEP TROPICAL MOISTURE TO ADVANCE
BACK INTO THE MID SOUTH. ISOLATED SHOWERS AND THUNDERSTORMS WILL
AGAIN BE POSSIBLE DURING PEAK HEATING ON BOTH FRIDAY AND SATURDAY.
A DRIER AIRMASS WILL WORK INTO THE AREA BY SUNDAY HELPING TO LIMIT
DIURNAL CONVECTION. TEMPERATURES WILL REMAIN SEASONALLY WARM WITH
INCREASING HUMIDITY LEVELS THROUGH THE END OF THE EXTENDED
FORECAST PERIOD.
JLH
.AVIATION...
06Z TAF SET
VFR CONDITIONS WILL DOMINATE...HOWEVER...SOME LOCATIONS MAY HAVE
SOME FOG IN THE MORNING. IF ANY FOG DOES DEVELOP EXPECT IT TO BE
MVFR CONDITIONS. WINDS LIGHT AND WILL SWITCH TO NORTH BY MORNING IN
ENTIRE REGION. AFTERNOON THUNDERSTORMS ARE TUESDAY ARE
POSSIBLE...HOWEVER NOT CONFIDENT ENOUGH WITH TIMING OR LOCATION AS
STORMS WILL BE AT BEST SCATTERED.
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 66 87 66 91 / 10 10 10 10
MKL 60 84 60 88 / 10 10 10 10
JBR 63 86 62 89 / 10 10 10 10
TUP 67 90 63 90 / 20 10 10 10
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS AMARILLO TX
444 AM CDT TUE JUN 12 2012
.DISCUSSION...
AN ACTIVE AND WET WX PATTERN IS TAKING SHAPE ACROSS THE AREA AS
FIRST ROUND OF SHOWERS AND THUNDERSTORMS ARE CURRENTLY MOVING ACROSS
PORTIONS OF THE FA. THESE STORMS WERE BECOMING MORE UPSCALE AS THEY
ENCOUNTER A MORE BUOYANT AIR MASS PER LAPS AND RAP DATA INDICATING
MUCAPES AROUND 200-600 J/KG. DIVERGENCE PROVIDED BY THE RRQ OF A JET
STREAK AND LFQ OF A JET STREAK NOSING INTO THE PANHANDLES ARE ALSO
HELPING TO INTENSIFY THESE STORMS. THESE STORMS WILL CONTINUE
THROUGH THE NEXT FEW HOURS WHERE 0-6 KM BULK SHEAR AROUND 30-40 KTS
AND STEEP MID-LEVEL LAPSE RATES CAN RESULT IN SOME OF THESE STORMS
TO BECOME SEVERE.
LATER TODAY...EXPECT A BIT OF A LULL IN THUNDERSTORM ACTIVITY ONCE
THIS EARLY MORNING CONVECTION EXITS THE AREA. HOWEVER SUFFICIENT LOW-
LEVEL MOISTURE WILL BE MAINTAINED ACROSS THE AREA ON BREEZY SOUTHEAST
SURFACE WINDS. SEVERAL UPPER-LEVEL DISTURBANCES WILL ALSO TRAVERSE
THE SOUTHERN PLAINS TODAY PROVIDING WEAK UPPER LIFT WHILE ANY
OUTFLOW BOUNDARIES CAN PROVIDE A FOCUS FOR STORM DEVELOPMENT.
FORECAST SOUNDINGS INDICATE THE AIR MASS WILL BE VERY UNSTABLE WITH
MLCAPES AROUND 2000-3000 J/KG. SHEAR WILL REMAIN MORE THAN ADEQUATE
TO ALLOW SOME STORMS TO BECOME SEVERE AND EXPECT THE MAIN SEVERE
THREATS TO BE LARGE HAIL AND STRONG WINDS. CONVECTION WILL BECOME
MORE WIDESPREAD TONIGHT AS A LOW-LEVEL JET SETTING UP ACROSS THE
SOUTHERN PLAINS WILL HELP TO MAINTAIN AND WARM...MOIST...AND
UNSTABLE AIR MASS ACROSS THE AREA. HIGHS TODAY SHOULD BE A LITTLE
COOLER...IN THE 80S.
ON WEDNESDAY THE SURFACE FLOW WILL TREND MORE TO THE SOUTH AS A COLD
FRONT THAT IS CURRENTLY SOUTH OF THE AREA LIFTS NORTH. WEAK MID-
LEVEL RIDGING WILL BUILD ACROSS THE SOUTHERN PLAINS HOWEVER SEVERAL
UPPER DISTURBANCES WILL QUICKLY BREAK DOWN THE RIDGE. MOIST AND
UNSTABLE CONDITIONS WILL REMAIN ACROSS THE AREA SO WILL CONTINUE
CHANCE POPS IN THE FORECAST. HAVE ALSO CONTINUED MENTION OF THUNDER
IN THE FORECAST THROUGH THE WEEKEND AS THE DRYLINE SHOULD REMAIN
WEST OF THE AREA WHILE SOUTHWEST UPPER FLOW TAPS INTO THE TROPICAL
MOISTURE OUT OF THE PACIFIC. STILL FAVOR BETTER CHANCES FOR STORMS
TO BE IN THE WEST AND CENTRAL SECTIONS OF THE FA GIVEN THE FORECAST
POSITION OF THE DRYLINE. THE STRENGTHENING OF A LEE TROUGH AND
POSSIBLE EASTWARD MOVEMENT OF THE DRYLINE EARLY NEXT WEEK SHOULD
END THUNDER CHANCES WITH THE NEXT POSSIBLE COLD FRONTAL INTRUSION
COMING AROUND MID-WEEK.
CLK
&&
.FIRE WEATHER...
ABUNDANT ATMOSPHERIC MOISTURE AND CHANCES FOR PRECIPITATION THROUGH
MUCH OF THE 7 DAY FORECAST PERIOD WILL PRECLUDE ELEVATED OR CRITICAL
FIRE WEATHER CONDITIONS ACROSS THE TX/OK PANHANDLES.
CLK
&&
.PRELIMINARY POINT TEMPS/POPS...
AMARILLO TX 83 63 87 66 92 / 40 50 30 20 20
BEAVER OK 86 63 93 67 96 / 20 40 30 20 20
BOISE CITY OK 85 62 88 63 94 / 30 40 30 20 20
BORGER TX 86 68 90 68 93 / 30 50 30 20 20
BOYS RANCH TX 85 64 91 65 96 / 40 50 30 20 20
CANYON TX 85 64 88 63 93 / 40 50 30 20 20
CLARENDON TX 84 67 88 67 92 / 40 60 30 20 20
DALHART TX 83 62 89 62 92 / 40 50 30 20 20
GUYMON OK 85 65 91 65 92 / 30 50 30 20 20
HEREFORD TX 83 66 87 61 92 / 40 50 30 20 20
LIPSCOMB TX 85 66 90 69 92 / 20 40 30 20 20
PAMPA TX 83 65 89 65 90 / 30 50 30 20 20
SHAMROCK TX 84 67 87 68 90 / 30 50 30 20 20
WELLINGTON TX 87 69 88 68 92 / 30 50 30 20 20
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
99/99
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1202 AM CDT TUE JUN 12 2012
.AVIATION...
SOME COMPLEXITIES TO THIS MORNINGS FORECAST CENTERED AROUND
POTENTIAL FOR CONVECTIVELY INDUCED OUTCOMES. MODEL GUIDANCE HAS
BEEN HINTING FOR DAYS AT DEVELOPING A MCS ACROSS THE NORTHERN PART
OF OUR FORECAST AREA...MOST LIKELY AFFECTING CHILDRESS.
HOWEVER..WHILE SOME DISCRETE ACTIVITY HAS FORMED IN NE NEW MEXICO
IT HAS FAILED TO GROW SUBSTANTIALLY UPSCALE. THEREFORE...GIVEN
OBSERVATIONS WILL NOT CALL FOR TSRA AT KCDS OVERNIGHT THOUGH THERE
IS A LOW PROBABILITY THAT IT WILL OCCUR. GUIDANCE IS LIKELY ALSO
INFLUENCED BY PERCEIVED CONVECTIVE THREAT IN DEVELOPING LOW LEVEL
MOISTURE AND SOME FOG. BUT...GIVEN 15 DEGREE TDD VALUES AND MID
LEVEL CLOUDS...WILL ALSO NOT BITE ON THAT BONE EITHER IN THE
OFFICIAL FORECAST. CONFIDENCE IS HIGHER FOR WEDNESDAY AFTERNOON
FOR MORE WIDESPREAD CONVECTION WHICH MAY AFFECT BOTH TERMINALS.
&&
.PREV DISCUSSION... /ISSUED 1012 PM CDT MON JUN 11 2012/
UPDATE...
CONVECTION SO FAR THIS EVENING HAS REMAINED REMOVED FROM THE CWA.
STORMS ASSOCIATED WITH THE FRONTAL BOUNDARY TO OUR SOUTH HAVE
SKIRTED AROUND THE SOUTHEAST EDGE OF THE FA THROUGH THE EVENING
HOURS UP TO THIS POINT. OUTFLOW FROM EARLIER ACTIVITY WAS IN CLOSE
PROXIMITY TO THE SOUTHERN ROLLING PLAINS AND COULD YET BE THE
FOCUS FOR STORM DEVELOPMENT THROUGH THE LATE EVENING HOURS.
ELSEWHERE...CONVECTION BETWEEN NOW AND MIDNIGHT DOES NOT SEEM AS
LIKELY AND HAVE DROPPED POPS GENERALLY TO AOB 20 PERCENT. AFTER
MIDNIGHT...INCREASINGLY MOIST/UNSTABLE EASTERLY LOW-LEVEL
FLOW...COUPLED WITH FAVORABLE UPPER JET DYNAMICS...AND A WEAK
UPPER DISTURBANCE COULD YET BE ENOUGH TO FORCE SOME LATE NIGHT
ELEVATED STORMS...IF WARM MID-LEVELS /CIN/ CAN BE OVERCOME. NOT
CERTAIN OF THIS SCENARIO...BUT THE 00Z NAM DOES CONTINUE TO
ADVERTISE A COMPLEX OF STORMS DEVELOPING ACROSS THE TEXAS
PANHANDLE AND ROLLING ACROSS THE NORTHEAST ZONES THROUGH EARLY
TUESDAY MORNING. THE 23Z HRRR DOES ALSO INDICATE THAT THE RATHER
ISOLATED CONVECTION IN NE NM WILL GROW UPSCALE LATE TONIGHT AND
MOVE ACROSS THE NORTHERN ZONES LATE TONIGHT. GIVEN THIS...HAVE
MAINTAINED CHANCE POPS OVER ROUGHLY THE NORTHEAST HALF OF THE FA
AFTER 06Z. GIVEN MODERATE INSTABILITY AND SUFFICIENT SHEAR...A FEW
ELEVATED STRONG TO SEVERE STORMS COULD BE POSSIBLE. UPDATED
FORECAST PRODUCTS HAVE BEEN SENT.
PREV DISCUSSION... /ISSUED 653 PM CDT MON JUN 11 2012/
AVIATION...
VFR CONDITIONS LOOK TO PREVAIL NEXT 24 HOURS WITH PERHAPS A CAVEAT
OR TWO. THUNDERSTORM CHANCES LOOK QUITE MEAGER THIS EVENING AND
HAVE DROPPED MENTION OF TSRA. MODELS HAVE BEEN HINTING AT AN MCS
MOVING OUT OF NEW MEXICO FOR A COUPLE DAYS DURING THE OVERNIGHT
HOURS. IF THIS ACTUALLY PLAYS OUT...KCDS LOOKS TO HAVE MOST LIKELY
SHOT AT GETTING STORMS BUT CONFIDENCE REMAINS TOO LOW TO INCLUDE
ATTM. AS MOIST AIR ADVECTION CONTINUES NEAR KCDS...WE COULD SEE
SOME LOW CLOUDS OR PERHAPS EVEN SOME LIGHT FOG DEVELOP THERE
TOWARD MORNING. INTO THE AFTERNOON HOURS ON TUESDAY...STORM
CHANCES WILL ONCE AGAIN INCREASE.
PREV DISCUSSION... /ISSUED 332 PM CDT MON JUN 11 2012/
SHORT TERM...
POTENTIALLY WET PATTERN DEVELOPING OVER THE NEXT 36 HOURS. SFC
ANALYSIS THIS AFTERNOON SHOWS A COLD FRONT THAT HAS JUST ABOUT
STALLED NEAR A HOBBS TO SWEETWATER TO WICHITA FALLS LINE. SOME
MOISTURE POOLING IS EVIDENT EITHER SIDE OF THE BOUNDARY. NORTH OF
THE FRONT UPSLOPE FLOW DEVELOPING ACROSS ERN NM AS WINDS SLOWLY VEER
TOWARD THE EAST. LOOKING AT TWO POTENTIAL AREAS OF THUNDERSTORM
DEVELOPMENT LATE THIS AFTERNOON OR EARLY THIS EVENING SHOULD CAPPING
INVERSION BE BREACHED...ONE BEING THE VCNTY OF THE COLD FRONT THAT
COULD SEE SOME STORMS MOVE INTO THE SERN ZONES AND THE SECOND BEING
THE HIGH TERRAIN JUST WEST OF THE FCST AREA WHERE MODESTLY MOIST
UPSLOPE FLOW MAY BE ENOUGH TO INITIATE ISO TO SCT THUNDER THERE WITH
A POTENTIAL TO MOVE INTO THE WRN ZONES DURING THE EVENING. MOVING
INTO THE OVERNIGHT HOURS AND EARLY TUESDAY BEGINS TO BREED MIXED
SIGNALS AS THE 12Z NAM AND THE 12Z TTU-WRF BOTH DEVELOP
THUNDERSTORMS ACROSS THE SRN PANHANDLE. GFS NOT SHOWING SIMILAR QPF
BUT IS SHOWING SIMILAR SUPPORT ONCE BEGIN TO LOOK AT MID LEVELS.
MODELS ARE PRETTY CONSISTING SHOWING MID LEVEL MOISTENING AS LARGE
MOISTURE PLUME EVIDENT ON WATER VAPOR IMAGERY SPREADS ACROSS THE
REGION. PROGGED SOUNDINGS SHOWING ABOUT 1500 J/KG OF CAPE LATE
TONIGHT WHEN LIFTING FROM ABOUT 750 MB BUT ALSO SHOWING ABOUT 100
J/KG OF CIN. HOWEVER...LIFT FROM MODEST MID LEVEL MOIST ISENTROPIC
MECHANISM AND PAIR OF JET STREAKS /ONE ACROSS CNTL PLAINS AND THE
OTHER ACROSS THE SRN ROCKIES/ MAY BE ENOUGH TO OVERCOME THE NEGATIVE
ENERGY WITH SCATTERED TSRA LOOKING POSSIBLE. WILL GO AHEAD AND FOCUS
ON THAT AREA WITH HIGHER CHANCE POPS AFTER 06Z WHILE PRE-06Z PERIOD
WILL FOCUS ON THE AFOREMENTIONED WRN AND SERN AREAS.
WHETHER THE SRN PANHANDLE CONVECTION CAN DEVELOP LATE TONIGHT AND
THEN BE SUSTAINED INTO THE 12Z-18Z PERIOD AS THE NAM SUGGEST WILL BE
KEY IN CONVECTIVE FCST FOR TUESDAY AFTN. OBVIOUSLY WIDESPREAD
CONVECTION DURING THE MORNING HOURS WOULD INITIALLY WEAKEN CHANCES
FOR PRECIP DURING PEAK CONVECTIVE HOURS TUESDAY AFTN ACROSS THE
ROLLING PLAINS. HOWEVER...FOCUS FOR INITIATION LOOKS LIKE IT MAY BE
FARTHER WEST IN A ZONE OF GENERALLY NW-SE ORIENTED MOISTURE
ADVECTION AS THE COLD FRONT LIFTS NWD TUESDAY AFTN. FCST HIGH
TEMPERATURES WILL BE COOLER...GENERALLY IN THE 80S...BUT RICH LOW
LEVEL MOISTURE SHOULD STILL MAKE FOR MLCAPE IN EXCESS OF 1500 J/KG
IN MUCH OF THE FCST AREA AND POSSIBLY APPROACHING 2500-PLUS IN A
BAND NEAR THE RETREATING FRONT. WILL CONTINUE WITH CHC POPS FOR NOW
RUNNING THE HIGHEST CHANCE ACROSS ROUGHLY THE WRN HALF OF THE AREA
WITH UNDERSTANDING THAT A RELATIVE MINIMUM ACROSS THE EAST MAY NOT
WORK OUT IF AFOREMENTIONED OVERNIGHT CONVECTION DOES NOT
MATERIALIZE. WILL THEN CONTINUE WITH HIGH CHANCE POPS TUESDAY AS
CONVECTION SPREADS EWD DURING THE EVENING AND THEN POTENTIAL FOR AN
MCS INTO THE NRN ZONES LATE IN THE NIGHT ROLLING IN FROM THE NW.
LONG TERM...
BY WEDNESDAY THE FRONTAL SYSTEM IS EXPECTED TO LIFT NORTHWARD AND
AREA RAIN CHANCES SHOULD BEGIN TO DECREASE. UPPER LEVEL MOISTURE
STREAMING OUT OF THE PACIFIC ACROSS MEXICO INTO THE AREA IS ONE
POSITIVE FACTOR. THE DRYLINE SHOULD REMAIN TO OUR WEST OVER NEW
MEXICO FOR MOST OF THE REMAINDER OF THE WEEK THROUGH NEXT WEEKEND.
THE SLIGHT CHANCE OF THUNDERSTORMS WHICH REMAINS IN THE FORECAST
THROUGH NEXT WEEKEND IS MOSTLY TIED TO DRYLINE ACTIVITY BEING PUSHED
EASTWARD WITH WESTERLY WINDS ALOFT IN THE LATE AFTERNOON AND EVENING
HOURS. BEST RAIN CHANCES WILL BE OVER OUR WESTERN COUNTIES.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 60 81 63 87 64 / 20 40 40 30 30
TULIA 62 80 64 87 64 / 40 40 50 30 20
PLAINVIEW 63 80 65 88 65 / 30 40 40 30 20
LEVELLAND 64 86 65 91 67 / 20 40 50 30 20
LUBBOCK 65 84 66 90 68 / 30 40 50 30 20
DENVER CITY 65 91 65 92 68 / 20 40 40 30 30
BROWNFIELD 66 90 68 91 68 / 20 40 50 30 20
CHILDRESS 66 85 67 88 68 / 40 50 50 20 20
SPUR 68 85 68 90 68 / 30 40 50 20 20
ASPERMONT 70 89 70 92 71 / 30 40 50 20 20
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/99/26
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
341 AM CDT TUE JUN 12 2012
.SHORT TERM...
TODAY AND TONIGHT...FORECAST CONFIDENCE MEDIUM TO HIGH.
MAIN ISSUES TODAY ARE AMOUNT OF CLOUD COVER AND TEMPERATURES.
CURRENT IR AND FOG PRODUCT SATELLITE IMAGERY INDICATING MOST OF THE
STRATOCU ASSOCIATED WITH THE COLD AIR ADVECTION WILL REMAIN CLOSE TO
SHORT WAVE TROUGH ACROSS NORTHERN WISCONSIN...BUT THERE IS A POCKET
OF SC FARTHER SOUTH IN CENTRAL MN AHEAD OF WEAK VORT MAX ON WATER
VAPOR LOOPS THAT WILL HAVE TO BE WATCHED...AS NAM AND RAP 925-850MB
RH FORECASTS INDICATE 60 PCT OR MORE CROSSING THE REGION THIS
MORNING INTO THIS AFTERNOON AND BOTH HAVE ENOUGH MOISTURE...THOUGH
SHALLOW...AROUND 4-5K FT ON MODEL SOUNDINGS FOR A BROKEN DECK.
HOWEVER...SFC DEW POINTS ON THOSE SOUNDINGS APPEAR A BIT HIGH...SO
WILL HOLD SKY COVER IN THE 40 PCT RANGE ACROSS THE NORTHERN CWA HAVE
PARTLY CLOUDY
850 MB AND 925 MB TEMPERATURES VERY SIMILAR ON ALL MODELS...THOUGH
00Z ECMWF 925 MB TEMPS ABOUT 2C TO 4C WARMER. WILL TREND TOWARD THE
COOLER BLENDED TEMPS FOR HIGHS IN THE UPPER 60S NORTH AND LOWER 70S
SOUTH.
CLEAR SKIES AND LIGHT WINDS TONIGHT AS SURFACE HIGH CROSSES STATE
WILL ALLOW GOOD RADIATIONAL COOLING CONDITIONS...WITH LOWS IN THE
40S EXPECTED EXCEPT NEAR THE LAKE AND THE FAR SOUTHEAST. FORCING
AHEAD OF NEXT WAVE REMAINS WEST THROUGH 12Z WEDNESDAY...WITH ONLY
THE LEADING EDGE OF MID TO HIGH LEVEL WARM AIR ADVECTION CLOUDS
REACHING THE WESTERN CWA BY MORNING. THE COOL OVERNIGHT LOWS WILL
PRODUCE SOME PATCHY FOG IN THE WI RIVER VALLEY.
WEDNESDAY THROUGH THURSDAY...FORECAST CONFIDENCE HIGH.
HIGH PRESSURE WILL DRIFT ACROSS THE GREAT LAKES REGION THROUGH
THURSDAY. EASTERLY FLOW WILL KEEP LAKESHORE AREAS COOLER THAN INLAND
AREAS. 925MB TEMPS WILL STEADILY INCREASE...UP TO AROUND 20C IN
SOUTH CENTRAL WI BY THU AFTERNOON...YIELDING MAX TEMPS AROUND 80.
DEWPOINT TEMPS SEEM CHARACTERISTICALLY OVERDONE BY THE MODELS GIVEN
THAT THERE IS LIMITED MOISTURE RETURN WITH THE WAA...SO WENT WITH
THE BIAS-CORRECTED LOWER VALUES GENERALLY IN THE 40S.
A 500MB SHORTWAVE IS EXPECTED TO MOVE ACROSS SOUTHERN/CENTRAL WI WED
NIGHT WHICH SHOULD LEAD TO MID CLOUDS OVERHEAD. TOO DRY AND NOT
ENOUGH DEEP LEVEL FORCING FOR ANY PRECIP.
.LONG TERM...
FRIDAY THROUGH TUESDAY...FORECAST CONFIDENCE MEDIUM TO HIGH.
THE UPPER LEVEL PATTERN IN THE EXTENDED RANGE FORECAST SHOWS A REX
BLOCK RETROGRADING INTO THE CENTER OF THE COUNTRY. HIGH PRESSURE
RIDGING WILL LIKELY KEEP SOUTHEAST WI ON THE DRY SIDE OF A
STATIONARY FRONTAL BOUNDARY SETTING UP ACROSS CENTRAL/NORTHERN WI.
SEVERAL SHORTWAVES WILL TRACK ALONG THE FRONT DURING THIS
PERIOD...LEADING TO THE SMALL CHANCES FOR THUNDERSTORMS MENTIONED IN
MAINLY SOUTH CENTRAL WI.
THE ECMWF LOOKS A LITTLE TOO PROGRESSIVE WITH BREAKING DOWN THE
RIDGE AND DROPPING THE FRONT THROUGH SOUTHERN WI ALREADY ON TUE. THE
NWS HYDROMETEOROLOGICAL PREDICTION CENTER /HPC/ FAVORS THE SLOWER
SOLUTION OF THE 00Z GFS AND 00Z ECMWF ENSEMBLE MEAN MODEL BLEND.
THIS WOULD KEEP SOUTHERN WI GENERALLY DRY THROUGH TUESDAY.
TEMPS WILL WARM BACK INTO THE MID 80S TO LOWER 90S INLAND FROM LAKE
MICHIGAN WITH PERSISTENT SOUTHERLY FLOW THROUGH MONDAY AND LIKELY
BEYOND.
&&
.AVIATION/12Z TAFS/...
LOOKING AT VFR CONDITIONS THROUGH THE FORECAST. MORNING MIXING WILL
BRING MORE CONSISTENT WIND GUSTS IN THE 15 TO 20 KNOT RANGE...EASING
THROUGH THE LATE AFTERNOON AND EVENING AS HIGH PRESSURE SLIDES OVER
STATE. EXPECTING MAINLY SCATTERED STRATOCUMULUS TODAY...THOUGH BASED
ON SATELLITE IMAGERY THERE IS A CHANCE FOR A BROKEN 4-5K FT DECK TO
PASS MAINLY JUST NORTH OF THE TAF SITES THAT WILL HAVE TO BE
MONITORED UP TO ISSUANCE TIME. CLEAR SKIES AND LIGHT WINDS TONIGHT
MAY BRING SOME PATCHY GROUND FOG...BUT POTENTIAL TOO LOW TO MENTION.
BEST CHANCE FOR VSBY REDUCING FOG WILL BE IN THE WI RIVER VALLEY
TONIGHT.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...REM
WEDNESDAY THROUGH MONDAY...MRC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1113 PM CDT MON JUN 11 2012
.SHORT TERM...THROUGH WEDNESDAY NIGHT
253 PM CDT MON JUN 11 2012
MAIN FORECAST CONCERN IS WITH THE TEMPERATURES THROUGH TUESDAY AND
RAIN CHANCES FOR WEDNESDAY NIGHT.
SURFACE ANALYSIS THIS AFTERNOON SHOWS A WIND SHIFT/DRY LINE
EXTENDING FROM NORTH CENTRAL WISCONSIN THROUGH THE FORECAST AREA
INTO NORTHWEST MISSOURI. LOCAL RADAR SHOWS A FEW SHOWERS
DEVELOPING ALONG THIS BOUNDARY.
THE HRRR HAS BEEN CONSISTENTLY SHOWING THE SHOWERS FORMING OVER
THE AREA THIS AFTERNOON. THE 11.15Z RUN CONTINUES THIS TREND
SHOWING THEM MOVING TO THE EAST THROUGH THE REMAINDER OF THE
AFTERNOON WITH THE BOUNDARY. THE SHOWERS AND BOUNDARY ARE EXPECTED
TO BE EAST OF THE FORECAST AREA BY 00Z...SO NO PLANS TO CARRY ANY
EVENING RAIN CHANCES.
AFTER THAT...IT IS A QUESTION OF HOW MUCH COOL AIR SETTLES IN OVER
THE AREA AS HIGH PRESSURE BUILDS IN. BOTH THE 11.12Z NAM AND GFS
INDICATE 925 MB TEMPERATURES SHOULD DIP DOWN TO 5-7C TONIGHT
BEFORE STARTING TO REBOUND TO AROUND 10C TUESDAY NIGHT. SURFACE
TEMPERATURES WILL GENERALLY FALL TO AROUND 50 TONIGHT AS A
NORTHWEST BREEZE IS EXPECTED TO CREATE JUST ENOUGH MIXING TO KEEP
THEM FROM GOING ANY LOWER. HIGHS TUESDAY WILL BE MUCH COOLER
TOPPING OUT IN THE UPPER 60S TO LOWER 70S. THE COOLEST NIGHT WILL
BE TUESDAY NIGHT DESPITE THE SLIGHTLY WARMER 925 MB TEMPERATURES.
THE SURFACE HIGH WILL BE RIGHT OVER THE AREA ALLOWING THE WINDS TO
DECOUPLE AND EXCELLENT RADIATIONAL COOLING TO OCCUR. EXPECTING
LOWS TO BE IN THE 40S WITH THE FAVORED COOLER SPOTS DIPPING INTO
THE UPPER 30S.
AS THE SURFACE HIGH THEN MOVES OFF TO THE EAST...THE CONCERN
BECOMES WHETHER THERE WILL BE ANY SHOWERS THAT DEVELOP IN THE
RETURN FLOW. THE MODELS SUGGEST THERE WILL BE A SHORT WAVE TROUGH
MOVING ACROSS THE DAKOTAS WEDNESDAY NIGHT WITH THE BEST PV
ADVECTION IN THE 500-300MB LAYER STAYING NORTHWEST OF THE AREA.
THE BEST LOW LEVEL MOISTURE TRANSPORT WILL BE INTO THIS WAVE...BUT
THERE WILL ALSO BE A WEAKER BRANCH SPLITTING OFF TO THE NORTHEAST
AHEAD OF ANOTHER SHORT WAVE TROUGH. THIS PLACES THE WESTERN
SECTIONS OF THE FORECAST UNDER UNDER THE EASTERN CONVERGENT SIDE
OF THE MOISTURE TRANSPORT AXIS. THIS IS EXPECTED TO COINCIDE WITH
1-2 UBAR/S OF UP GLIDE ON THE 310K ISENTROPIC SURFACE AND WHILE
THE FORCING IS NOT THAT STRONG FELT THERE WAS ENOUGH TO JUSTIFY A
20 PERCENT RAIN CHANCES LATE TUESDAY NIGHT OVER THE NORTHWEST
SECTIONS OF THE AREA.
.LONG TERM...THURSDAY THROUGH MONDAY
253 PM CDT MON JUN 11 2012
CONSIDERABLE UNCERTAINTY IN THE EXTENDED PART OF THE FORECAST. THE
UPPER LEVEL RIDGE IS EXPECTED TO BUILD FROM THE SOUTHERN PLAINS
INTO SOUTHEAST CANADA. MODELS HAVE BEEN SHOWING RUN TO RUN
DIFFERENCES ON HOW FAR WEST THE RIDGE WILL EXTEND AND WHETHER THIS
WILL ALLOW ANY SHORT WAVE TROUGHS IN THE SOUTHWEST FLOW TO IMPACT
THE AREA. THE 11.12Z ECMWF HAS COME IN WITH AN EVEN FLATTER AND
FARTHER EAST RIDGE AXIS WHICH ALLOWS A SYSTEM TO MOVE ACROSS THE
UPPER MIDWEST FOR THE WEEKEND. THE GFS AND 11.12Z GEM ARE MORE
ROBUST WITH THE RIDGE AXIS WHICH DEFLECTS THIS SYSTEM OFF TO THE
NORTHWEST. MODELS ARE KNOWN TO STRUGGLE MIGHTILY WITH SOUTHWEST
FLOW SO HAVE OPTED TO LEAVE IN THE SMALL RAIN CHANCES AS
CONFIDENCE TO PULL THEM OUT IS JUST NOT THERE.
&&
.AVIATION...THROUGH 06Z WEDNESDAY
1113 PM CDT MON JUN 11 2012
CLEAR SKIES WILL PERSIST OVERNIGHT WITH A WEAK VFR FAIR WEATHER
CUMULUS FIELD DEVELOPING LATE TUESDAY MORNING INTO THE AFTERNOON. WINDS
WILL BE THE MAIN FOCUS THROUGH TUESDAY WITH THE PRESSURE GRADIENT
GRADUALLY WEAKENING INTO THE AFTERNOON. GUSTS HAVE STAYED UP
AROUND 20KTS AT LSE WHERE SOME CHANNELING OF THE WIND MAY BE
OCCURRING OUT OF THE WEST-NORTHWEST. MEANWHILE...THE GUSTS HAVE
SUBSIDED AT RST...BUT THERE HAVE BEEN OTHER OBSERVATIONS ACROSS
SOUTH CENTRAL MINNESOTA THAT ARE STILL GUSTING...SO AM NOT SOLD
THAT THEIR WINDS WILL STAY DOWN OVERNIGHT. THESE WINDS WILL WEAKEN
TUESDAY AFTERNOON AS A RIDGE OF HIGH PRESSURE MOVES INTO THE
REGION. THERE IS THE POSSIBILITY OF SOME RIVER VALLEY FOG
WEDNESDAY MORNING DUE TO THE COLD SURFACE AIR SITTING OVER THE
WARM MISSISSIPPI RIVER...BUT ANY VISIBILITY REDUCTIONS WOULD COME
SOMETIME AFTER 6Z...IF AT ALL.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
253 PM CDT MON JUN 11 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION...HALBACH
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
744 AM EDT TUE JUN 12 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 602 AM EDT TUE JUN 12 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A FAIRLY DEEP TROF
EXTENDING FROM HUDSON BAY TO THE UPPER GREAT LAKES. ONE VORT MAX IS
MOVING ACROSS LAKE SUPERIOR/UPPER MI ATTM AND ANOTHER WEAKER VORT
MAX IS DROPPING SE INTO NRN MN. AT THE SFC...COLD FRONT HAS CLEARED
THE FCST AREA...AND STRONG CAA IS UNDERWAY. 850MB TEMPS WHICH WERE
RUNNING 10-16C AT 00Z SHOULD BE DOWN TO 0 TO 2C AT 18Z TODAY.
WITH 850MB THERMAL TROF ARRIVING BY MID DAY...EXPECT PLENTY OF CLOUD
COVER THRU THE MORNING HRS. SECONDARY SHORTWAVE BRUSHING THE AREA
MIGHT BRING A FEW -SHRA/SPRINKLES ACROSS THE N AS WELL. THERE HAVE
BEEN OCNL REPORTS OF LIGHT PCPN IN NRN MN DURING THE NIGHT. CLOUDS
SHOULD SLOWLY BEGIN TO BREAK UP FROM W TO E DURING THE AFTN. MODELS
ARE FAIRLY AGGRESSIVE WITH THE DRYING/CLEARING TREND. MIGHT BE A BIT
TOO QUICK GIVEN PROXIMITY OF THERMAL TROF DURING THE LATTER PORTION
OF THE DAY. UNDER CLOUDS/CAA...TEMPS SHOULD RISE VERY LITTLE THIS
MORNING. IN FACT...TEMPS OVER THE E MAY FALL A FEW DEGREES DURING
THE MORNING...ESPECIALLY CLOSE TO LAKE SUPERIOR. DURING THE AFTN...
TEMPS MAY NOT GET OUT OF THE UPPER 40S E OF MUNISING GIVEN CHILLY
AIR MASS AND STRONG GRADIENT FLOW ACROSS THE LAKE. ELSEWHERE...TEMPS
WILL BEGIN TO RISE DURING THE AFTN AS CLOUDS SLOWLY BEGIN TO BREAK
UP FROM W TO E. WITH EXPECTATION OF SOME SUN...UPPER 50S/LWR 60S
SHOULD GENERALLY BE THE RULE. MAY REACH THE MID 60S OVER THE SCNTRL.
COLD AIR ARRIVING TODAY WILL SET THE STAGE FOR A CHILLY/POSSIBLY
FROSTY NIGHT TONIGHT. WITH SFC HIGH PRES MOVING INTO THE VCNTY...
WINDS WILL DROP TO CALM/NEAR CALM. DRY AIR MASS (PRECIPITABLE WATER
35 TO 50PCT OF NORMAL THRU AT LEAST THE FIRST HALF OF THE NIGHT)
WILL ALLOW FOR STRONG RADIATIONAL COOLING UNDER CLEAR SKIES. RIGHT
NOW...IT APPEARS GREATEST COVERAGE OF FROST WILL BE OVER THE
INTERIOR W HALF TOWARD THE WI BORDER. HAVE THUS OPTED FOR A FROST
ADVY FOR GOGEBIC/IRON/DICKINSON LATE TONIGHT. MAY NEED TO EXPAND
ADVY EASTWARD IN LATER FCSTS SINCE LOWEST PRECIPITABLE WATER LINGERS
LONGEST OVER THE E.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 602 AM EDT TUE JUN 12 2012
WED MORNING WILL START WITH A SFC HIGH OVER THE CWA AND ZONAL FLOW
ALOFT. AS THE SFC HIGH CENTER MOVES TO LAKE HURON BY 00Z THU...SLY
FLOW WILL BE INCREASING THROUGH THE DAY SUNDAY. 850MB TEMPS WILL
INCREASE FROM A CWA AVG OF 4C 12Z WED TO 9C 00Z THU. WE SHOULD BE
ABLE TO MIX TO AROUND 800MB WED AFTERNOON...RESULTING IN HIGH TEMPS
IN THE MID 60S TO MID 70S AND MIN RH VALUES OF 20 TO 30 PERCENT
INTERIOR W...AND 25 TO 35 PERCENT INTERIOR E. THANKFULLY...WINDS
SHOULD BE LESS THAN 15MPH WITH GUSTS OF 20MPH OR LESS.
A SHORTWAVE TROUGH WILL MOVE E OVER LAKE WINNIPEG BY 00Z FRI...WITH
A SFC LOW BENEATH IT AND A SFC TROUGH STRETCHING INTO WRN MN. WHILE
THE SFC HIGH WILL HAVE MOVED WELL INTO QUEBEC...A SFC RIDGE WILL
REMAIN OVER THE LOWER GREAT LAKES...INCREASING THE PRESSURE GRADIENT
/AND THUS THE SLY FLOW/ OVER THE CWA. BY 00Z THU...850MB TEMPS WILL
INCREASE TO AROUND 15C...MAKING FOR HIGH TEMPS IN THE 70S TO LOW 80S
OVER MOST OF UPPER MI. WITH THE INCREASED SLY FLOW...MID LEVEL
MOISTURE WILL BE GREATER THAN ON WED...BUT MODELS SHOW A VERY DRY
LAYER AROUND 875MB...SO RH VALUES MAY FALL TO AROUND 30 PERCENT
INLAND ON THU. SOME MODELS DO TRY TO BRING IN SOME PRECIP OVER FAR
WRN UPPER MI AND WRN LAKE SUPERIOR...BUT MAJORITY OF GUIDANCE KEEPS
THE PRECIP JUST W OF THE CWA. WILL GO WITH THE DRIER IDEA GIVEN VERY
DRY LOW LEVELS AND DRY TREND AS OF LATE. GENERALLY...SFC WINDS
SHOULD BE AROUND 15MPH WITH GUSTS OF 20-25MPH THU AFTERNOON/EVENING.
THE WINNIPEG SHORTWAVE MOVES TO HUDSON BAY BY 18Z FRI...BUT THE SFC
TROUGH SHOULD STAY NW OF THE CWA THROUGH FRI. MODELS ARE IN FAIRLY
GOOD GENERAL AGREEMENT SHOWING SOME PRECIP ACROSS THE CWA FRI AS
STRONG SLY FLOW CONTINUES. WE SHOULD SEE BETTER MOISTURE...SO SOME
PRECIP IS POSSIBLE...BUT WE WILL BE LACKING A GOOD FORCING MECHANISM
SO WILL NOT GO HIGHER THAN LOW CHANCE POPS. 850MB TEMPS INCREASE A
DEGREE OR TWO FROM THU...RESULTING IN HIGH TEMPS FROM THE MID 70S TO
MID 80S...WARMEST INTERIOR W.
MODEL AGREEMENT INCREASES CONSIDERABLY FOR SAT THROUGH MON WITH THE
PASSAGE OF A SERIES OF SHORTWAVES...DECREASING FORECAST CONFIDENCE
SIGNIFICANTLY. MODELS ARE IN GENERAL AGREEMENT IN SHOWING A DEEP
UPPER TROUGH MOVING INTO THE NRN PLAINS STATES MON...BUT HOW DEEP
AND HOW FAR E THE TROUGH IS REMAINS IN QUESTION...AND THESE ASPECTS
OF THIS SYSTEM WILL PLAY A CRUCIAL ROLE FOR THE FORECAST FOR MON.
USED A CONSENSUS OF MODELS FOR THIS TIME FRAME.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 742 AM EDT TUE JUN 12 2012
THERMAL TROF APPROACHING THE AREA WILL BE CONDUCIVE FOR MAINTAINING
BKN/OVC STRATOCU THRU THE MORNING HRS WITH CIGS PREDOMINATELY MVFR
AT KIWD/KCMX/KSAW. PER UPSTREAM OBS...CIGS WILL PROBABLY BOUNCE TO
VFR AT TIMES...ESPECIALLY HEADING INTO THE LATE MORNING/EARLY AFTN.
DISTURBANCE PASSING THRU THE AREA MAY ALSO PRODUCE SOME
-RA/SPRINKLES AT TIMES FOR THE NEXT 2-3HRS...PARTICULARLY AT KCMX.
ARRIVAL OF DRIER AIR WILL WORK TO SCATTER OUT CLOUDS THIS AFTN/EARLY
EVENING...BEGINNING FIRST AT KIWD AND LAST AT KSAW. INFLUX OF SHARPLY
COLDER AIR WILL ALSO KEEP NW WINDS GUSTY TODAY...ESPECIALLY AT KCMX.
WITH HIGH PRES NEARING AND LOSS OF DAYTIME HEATING/MIXING...WINDS
WILL BECOME LIGHT THIS EVENING UNDER CLEAR SKIES.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 602 AM EDT TUE JUN 12 2012
STRONG PUSH OF COLDER AIR INTO THE UPPER LAKES WILL RESULT IN W TO
NW WINDS OF 20-30KT TODAY. THERE MAY BE A FEW GALE FORCE GUSTS ON
SOME OF THE HIGHEST OBSERVING PLATFORMS OVER THE E HALF OF THE LAKE
THRU THE MORNING HRS. HIGH PRES OVER THE NRN PLAINS WILL THEN ARRIVE
OVER THE WESTERN GREAT LAKES TONIGHT...RESULTING IN WINDS
DIMINISHING TO UNDER 20KT FROM W TO E LATE THIS AFTN THRU TONIGHT.
THE HIGH WILL SHIFT TO QUEBEC WED NIGHT...AND THEN FOR THE REMAINDER
OF THE WEEK...THE BASIC PATTERN WILL FEATURE A HIGH PRES RIDGE OVER
THE ERN CONUS WITH A LOW PRES TROF FROM THE WRN HIGH PLAINS TO
HUDSON BAY. A WAVE OF LOW PRES LIFTING TOWARD HUDSON BAY THU/FRI MAY
RESULT IN A PERIOD OF SOUTHERLY 15-25KT WINDS THU/THU NIGHT OVER
CNTRL LAKE SUPERIOR. OTHERWISE...WINDS WILL BE UNDER 20KT WED THRU
SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
FROST ADVISORY FROM MIDNIGHT TONIGHT TO 6 AM CDT WEDNESDAY FOR
MIZ009>011.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1052 AM EDT TUE JUN 12 2012
.SYNOPSIS...
A COLD FRONT WILL SWEEP WEST TO EAST ACROSS THE REGION TODAY. A MUCH
DRIER AIR MASS WILL BEGIN TO BUILD ACROSS THE SOUTHERN APPALACHIAN
REGION TONIGHT. SURFACE HIGH PRESSURE IS EXPECTED TO REMAIN OVER THE
WESTERN CAROLINAS AND NORTHEAST GEORGIA INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1045 AM...SHRA ASSOCIATED WITH WEAK SHORT WAVE AND WEAK SFC
BOUNDARY WILL MOVE EAST OF THE I-77 CORRIDOR BEFORE NOON. ALTHOUGH
WLY FLOW AND DRIER AIR MASS IS TO THE WEST AND COULD MOVE INTO AT
LEAST THE WRN CWFA THIS AFTERNOON...LOW LEVEL MOISTURE WILL REMAIN
HIGH ACROSS THE AREA. 12Z KGSO RAOB IS INDICATIVE OF THE MOIST AIR
MASS WHILE THE KFFC RAOB SHOWS THE DRIER WLY FLOW AIR MASS. THE
DRIER AIR MASS SUPPORTS HIGHER INSTABILITY WITH BETTER SFC HEATING
AND COOLER MID LEVEL TEMPS. WITH SOME CLEARING OVER THE WEST...
EXPECT MORE INSTABILITY THERE AND AN EARLIER CONVECTIVE INITIATION.
STORMS SHOULD DEVELOP/MOVE INTO THE ERN CWFA WHERE INSTABILITY
DEVELOPS LATER. WITH THE DRIER AIR MASS...DRIER MID LEVELS COULD
LEAD TO AN INCREASED CHC OF DOWNBURSTS WHERE STRONGER STORMS FORM.
VERY LITTLE SHEAR IS SHOWN ON THE OBSERVED RAOBS OR 12Z UPPER AIR
CHARTS...SO NO SIGNIFICANT ORGANIZATION IS EXPECTED. HAVE UPDATED
HIGHS WITH THE LATEST BIAS CORRECTED GUIDANCE WHICH SHOWS THE TEMP
DISCONTINUITY BETWEEN THE DRIER WEST AND MOISTER EAST QUITE WELL.
AS OF 510 AM TUESDAY...ISOLATED SHRA ARE AFFECTING MOST OF THE FA
ATTM. AREAS OF DRIZZLE HAVE ALSO STARTED TO DEVELOP PER LOWERING
VSBYS ON SOME REGION ASOS AND AWOS STATIONS. DRIZZLE HAS BEEN ADDED
TO THE ZONES FOR ALL FOOTHILL AND PIEDMONT LOCATIONS THROUGH 12 UTC
AS LOW CLOUDS AND WEAK LLVL ISENTROPIC UPGLIDE WILL CONTINUE THROUGH
THIS TIME. POPS HAVE ALSO BEEN RAISED A LITTLE ALONG THE TN LINE. A
WEAK MCV WILL APPROACH FROM THE WEST. IT HAS TRIGGERED SHOWERS OVER
ERN TN AND THEY SHOULD BEGIN TO AFFECT THE WRN NC MTNS WITHIN THE
NEXT 1 TO 2 HOURS.
PREVIOUS DISCUSSION...
THE LATEST RUN OF THE RAP HAD A CONVECTIVELY INDUCED H5 SHORT WAVE
OVER ERN TN. IT DROPS THIS FEATURE SOUTHEASTWARD DURING THE COURSE
OF THE MORNING...AND BY EARLY AFTN IT/S LOCATED OVER SOUTH CENTRAL
GA. THE GFS MAINTAINS A STRONGER SHORT WAVE OVER THE WRN
CAROLINAS... WHILE THE NAM IS NOT A STRONG WITH THE WAVE.
OVERALL...THE GFS MAY BE OVERDONE WITH THIS FEATURE. THE GFS BUFKIT
SOUNDINGS LOOK MODESTLY IMPRESSIVE THIS AFTN WITH CAPE VALUES
RANGING FROM 1200-1500 J/KG AND LITTLE IF ANY INHIBITION. THE NAM
STILL HAS PLENTY OF INSTABILITY...BUT IT MAINTAINS MORE CAPPING IN
THE LOW LEVELS. I STILL PLAN TO CARRY LOW END LIKELY POPS ACROSS
MOST OF THE FA...AND IN PARTICULAR THE I-77 CORRIDOR...BUT THE
RECENT SOUTHWARD SHIFT OF THE SHORT WAVE DOES NOT BODE AS WELL FOR
EXTENSIVE CONVECTIVE COVERAGE. WITH MORE DRYING ALOFT...THERE IS A
CHANCE FOR A FEW DAMAGING DOWNBURSTS TODAY. IN FACT...THE NAM SFC
DELTA THETA-E VALUES ARE IN THE MID 20S WHICH WOULD CERTAINLY
SUPPORT DAMAGING WINDS WITH THE STRONGER STORMS THIS AFTERNOON.
A COLD FRONT WILL CROSS THE REGION OVERNIGHT. I HAVE CONVECTION
ENDING FAIRLY QUICKLY THIS EVENING AS THE SOUNDINGS SHOW
CONSIDERABLE LOW LEVEL INHIBITION EVEN WITH THE BNDRY PUSHING ACROSS
THE REGION.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
AS OF 220 AM TUESDAY...BY DAYBREAK WEDNESDAY....THE COLD FRONT WILL
SLIDE EAST OFF THE CAROLINA COAST AS HIGH PRESSURE BUILDS ACROSS THE
GREAT LAKES AREA. A BLEND OF THE GFS AND ECMWF INDICATES THAT THE
CWA WILL REMAIN ON THE SOUTHERN EDGE OF SFC HIGH PRESSURE WEDNESDAY
AND THURSDAY. IN THE MID LEVELS...THE EARLY PHASE OF AN OMEGA BLOCK
WILL DEVELOP ACROSS THE CONUS...WITH RIDGING BUILDING NORTH ACROSS
THE MISSISSIPPI AND OHIO RIVER VALLEYS. BOTH SOLUTIONS INDICATE THAT
A SHALLOW POOL OF MOISTURE AND WEAK INSTABILITY WILL REMAIN ACROSS
THE NC MTNS WEDNESDAY AND THURSDAY. I WILL CONTINUE TO INDICATE
DIURNAL SCHC POPS ACROSS THE MTNS...ISO ACROSS THE FOOTHILLS AND
PIEDMONT. HIGH TEMPERATURES MAY RANGE FROM L80S ACROSS THE MTN
VALLEYS TO THE U80S TO AROUND 90 DEGREES EAST OF I-85 ON WEDNESDAY.
HIGH TEMPERATURES ON THURSDAY MAY REMAIN AROUND 1 TO 2 DEGREES
COOLER THAN WEDNESDAY. LOWS WEDNESDAY NIGHT ARE FORECAST TO RANGE
FROM U50S ACROSS THE MTNS TO MID 60S EAST.
&&
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
AS OF 230 AM TUESDAY...FRIDAY THROUGH MONDAY...THE MID LEVEL PATTERN
WILL REMAIN SOLIDLY BLOCK THROUGH MOST OF THE PERIOD...BEGINNING TO
WEAKEN EARLY NEXT WEEK. THE MAIN MID LEVEL FEATURES WILL REMAIN THE
RIDGE CENTER ACROSS THE MID WEST WITH LOW PRESSURE OVER THE WESTERN
ATLANTIC. AT THE SFC...HIGH PRESSURE WILL REMAIN CENTERED OVER NEW
ENGLAND WITH RIDGING EXTENDING SW ACROSS THE CWA. GFS FORECAST
SOUNDINGS INDICATES THAT WEAK INSTABILITY AND WEAK LLVL CIN WILL
EXIST ACROSS THE MTNS EACH AFTERNOON AND EVENING. I WILL MAINTAIN
DIURNAL SCHC ACROSS THE MTNS FOR SHRA AND TSRA. TEMPERATURES EACH
DAY SHOULD CHANGE VERY LITTLE FROM DAY TO DAY...RANGING FROM U70S
ACROSS THE MTN VALLEYS TO MID 80S EAST. LOW TEMPERATURES ARE
FORECAST TO RANGE FROM U50S ACROSS THE MTN VALLEYS TO L60S EAST.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
AT KCLT...MOIST SOUTHWEST FLOW SHOULD KEEP CIGS IN THE 200 TO 400
FOOT RANGE UP UNTIL AROUND 14 UTC. THEREAFTER THE CIGS SHOULD LIFT
FAIRLY QUICKLY. AREAS OF DRIZZLE AND FOG AND A FEW HEAVIER SHRA WILL
ALSO LAST THROUGH 14 UTC. BY EARLY AFTN SCT TO NUMEROUS SHRA/TSTMS
WILL DEVELOP AROUND THE AIRFIELD AS AN UPPER LOW CROSSES THE REGION.
THE STORMS SHOULD END AROUND 00 UTC. A COLD FRONT WILL CROSS THE
AIRFIELD ABOUT THAT TIME...TURNING WINDS LIGHT OUT OF THE NORTHWEST.
THE WINDS WILL BECOME A LITTLE STRONGER AND TURN OUT OF THE NE
TOWARD MORNING.
KAVL AND KHKY...DOWNSLOPE FLOW HAS MADE IT HARDER FOR LOW CIGS TO
FORM AT KAVL AND KHKY. AFTER 12 UTC CONDITIONS ARE GENERALLY
EXPECTED TO BE VFR...THOUGH PATCHES OF IFR STRATUS WILL STILL BE IN
THE VICINITY UNTIL AROUND 13 UTC. AN UPPER LOW WILL CROSS THE REGION
LATE THIS MORNING AND INTO THE AFTN. THIS WILL TRIGGER SCT TO
NUMEROUS SHRA AND TSTMS IN THE VCNTY OF BOTH AIRFIELDS. THE WINDS
SHOULD TURN OUT OF THE NW AT KHKY BY LATE AFTN AND THE WINDS WILL BE
NW THROUGH THE DAY AT KAVL. DRIER AIR TONIGHT SHOULD LIMIT ANY
RESTRICTIONS TO A BRIEF PERIOD OF MVFR FOG.
ELSEWHERE...200 TO 400 FOOT CIGS SHOULD LIFT INTO THE THE MVFR RANGE
BY 14 UTC AS THE WINDS TURN MORE DOWNSLOPE AT KGMU AND KGSP. AREAS
OF DRIZZLE AND FOG WILL END BY THAT TIME AS WELL. CONDITIONS WILL BE
BETTER AT KAND. SCT TSTMS WILL DEVELOP IN THE VCNTY OF THE AIRFIELDS
THIS AFTN AS AN UPPER LOW CROSSES THE REGION. THE CONVECTION SHOULD
END BY 00 UTC. A COLD FRONT WILL CROSS THE REGION OVERNIGHT. THE
WINDS WILL GRADUALLY TURN OUT OF THE WEST AND THEN NORTHWEST
OVERNIGHT. THE WINDS WILL INCREASE A LITTLE OUT OF THE NE BY SUNRISE
WED.
OUTLOOK...GENERALLY DRY CONDITIONS ARE NOW EXPECTED BEHIND A COLD
FRONT WEDNESDAY THROUGH SATURDAY. HOWEVER...ISOLATED AFTERNOON TSTMS
WILL DEVELOP OVER THE MTNS EACH DAY...WHICH COULD HAVE SOME AFFECT
ON OPERATIONS AT KAVL.
AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE
PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE
CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)...
WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...NED
NEAR TERM...MCAVOY/RWH
SHORT TERM...NED
LONG TERM...NED
AVIATION...MCAVOY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
733 AM EDT TUE JUN 12 2012
.SYNOPSIS...
A COLD FRONT WILL SWEEP WEST TO EAST ACROSS THE REGION TODAY. A MUCH
DRIER AIR MASS WILL BEGIN TO BUILD ACROSS THE SOUTHERN APPALACHIAN
REGION TONIGHT. SURFACE HIGH PRESSURE IS EXPECTED TO REMAIN OVER THE
WESTERN CAROLINAS AND NORTHEAST GEORGIA INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 510 AM TUESDAY...ISOLATED SHRA ARE AFFECTING MOST OF THE FA
ATTM. AREAS OF DRIZZLE HAVE ALSO STARTED TO DEVELOP PER LOWERING
VSBYS ON SOME REGION ASOS AND AWOS STATIONS. DRIZZLE HAS BEEN ADDED
TO THE ZONES FOR ALL FOOTHILL AND PIEDMONT LOCATIONS THROUGH 12 UTC
AS LOW CLOUDS AND WEAK LLVL ISENTROPIC UPGLIDE WILL CONTINUE THROUGH
THIS TIME. POPS HAVE ALSO BEEN RAISED A LITTLE ALONG THE TN LINE. A
WEAK MCV WILL APPROACH FROM THE WEST. IT HAS TRIGGERED SHOWERS OVER
ERN TN AND THEY SHOULD BEGIN TO AFFECT THE WRN NC MTNS WITHIN THE
NEXT 1 TO 2 HOURS.
PREVIOUS DISCUSSION...
THE LATEST RUN OF THE RAP HAD A CONVECTIVELY INDUCED H5 SHORT WAVE
OVER ERN TN. IT DROPS THIS FEATURE SOUTHEASTWARD DURING THE COURSE
OF THE MORNING...AND BY EARLY AFTN IT/S LOCATED OVER SOUTH CENTRAL
GA. THE GFS MAINTAINS A STRONGER SHORT WAVE OVER THE WRN
CAROLINAS... WHILE THE NAM IS NOT A STRONG WITH THE WAVE.
OVERALL...THE GFS MAY BE OVERDONE WITH THIS FEATURE. THE GFS BUFKIT
SOUNDINGS LOOK MODESTLY IMPRESSIVE THIS AFTN WITH CAPE VALUES
RANGING FROM 1200-1500 J/KG AND LITTLE IF ANY INHIBITION. THE NAM
STILL HAS PLENTY OF INSTABILITY...BUT IT MAINTAINS MORE CAPPING IN
THE LOW LEVELS. I STILL PLAN TO CARRY LOW END LIKELY POPS ACROSS
MOST OF THE FA...AND IN PARTICULAR THE I-77 CORRIDOR...BUT THE
RECENT SOUTHWARD SHIFT OF THE SHORT WAVE DOES NOT BODE AS WELL FOR
EXTENSIVE CONVECTIVE COVERAGE. WITH MORE DRYING ALOFT...THERE IS A
CHANCE FOR A FEW DAMAGING DOWNBURSTS TODAY. IN FACT...THE NAM SFC
DELTA THETA-E VALUES ARE IN THE MID 20S WHICH WOULD CERTAINLY
SUPPORT DAMAGING WINDS WITH THE STRONGER STORMS THIS AFTERNOON.
A COLD FRONT WILL CROSS THE REGION OVERNIGHT. I HAVE CONVECTION
ENDING FAIRLY QUICKLY THIS EVENING AS THE SOUNDINGS SHOW
CONSIDERABLE LOW LEVEL INHIBITION EVEN WITH THE BNDRY PUSHING ACROSS
THE REGION.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
AS OF 220 AM TUESDAY...BY DAYBREAK WEDNESDAY....THE COLD FRONT WILL
SLIDE EAST OFF THE CAROLINA COAST AS HIGH PRESSURE BUILDS ACROSS THE
GREAT LAKES AREA. A BLEND OF THE GFS AND ECMWF INDICATES THAT THE
CWA WILL REMAIN ON THE SOUTHERN EDGE OF SFC HIGH PRESSURE WEDNESDAY
AND THURSDAY. IN THE MID LEVELS...THE EARLY PHASE OF AN OMEGA BLOCK
WILL DEVELOP ACROSS THE CONUS...WITH RIDGING BUILDING NORTH ACROSS
THE MISSISSIPPI AND OHIO RIVER VALLEYS. BOTH SOLUTIONS INDICATE THAT
A SHALLOW POOL OF MOISTURE AND WEAK INSTABILITY WILL REMAIN ACROSS
THE NC MTNS WEDNESDAY AND THURSDAY. I WILL CONTINUE TO INDICATE
DIURNAL SCHC POPS ACROSS THE MTNS...ISO ACROSS THE FOOTHILLS AND
PIEDMONT. HIGH TEMPERATURES MAY RANGE FROM L80S ACROSS THE MTN
VALLEYS TO THE U80S TO AROUND 90 DEGREES EAST OF I-85 ON WEDNESDAY.
HIGH TEMPERATURES ON THURSDAY MAY REMAIN AROUND 1 TO 2 DEGREES
COOLER THAN WEDNESDAY. LOWS WEDNESDAY NIGHT ARE FORECAST TO RANGE
FROM U50S ACROSS THE MTNS TO MID 60S EAST.
&&
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
AS OF 230 AM TUESDAY...FRIDAY THROUGH MONDAY...THE MID LEVEL PATTERN
WILL REMAIN SOLIDLY BLOCK THROUGH MOST OF THE PERIOD...BEGINNING TO
WEAKEN EARLY NEXT WEEK. THE MAIN MID LEVEL FEATURES WILL REMAIN THE
RIDGE CENTER ACROSS THE MID WEST WITH LOW PRESSURE OVER THE WESTERN
ATLANTIC. AT THE SFC...HIGH PRESSURE WILL REMAIN CENTERED OVER NEW
ENGLAND WITH RIDGING EXTENDING SW ACROSS THE CWA. GFS FORECAST
SOUNDINGS INDICATES THAT WEAK INSTABILITY AND WEAK LLVL CIN WILL
EXIST ACROSS THE MTNS EACH AFTERNOON AND EVENING. I WILL MAINTAIN
DIURNAL SCHC ACROSS THE MTNS FOR SHRA AND TSRA. TEMPERATURES EACH
DAY SHOULD CHANGE VERY LITTLE FROM DAY TO DAY...RANGING FROM U70S
ACROSS THE MTN VALLEYS TO MID 80S EAST. LOW TEMPERATURES ARE
FORECAST TO RANGE FROM U50S ACROSS THE MTN VALLEYS TO L60S EAST.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
AT KCLT...MOIST SOUTHWEST FLOW SHOULD KEEP CIGS IN THE 200 TO 400
FOOT RANGE UP UNTIL AROUND 14 UTC. THEREAFTER THE CIGS SHOULD LIFT
FAIRLY QUICKLY. AREAS OF DRIZZLE AND FOG AND A FEW HEAVIER SHRA WILL
ALSO LAST THROUGH 14 UTC. BY EARLY AFTN SCT TO NUMEROUS SHRA/TSTMS
WILL DEVELOP AROUND THE AIRFIELD AS AN UPPER LOW CROSSES THE REGION.
THE STORMS SHOULD END AROUND 00 UTC. A COLD FRONT WILL CROSS THE
AIRFIELD ABOUT THAT TIME...TURNING WINDS LIGHT OUT OF THE NORTHWEST.
THE WINDS WILL BECOME A LITTLE STRONGER AND TURN OUT OF THE NE
TOWARD MORNING.
KAVL AND KHKY...DOWNSLOPE FLOW HAS MADE IT HARDER FOR LOW CIGS TO
FORM AT KAVL AND KHKY. AFTER 12 UTC CONDITIONS ARE GENERALLY
EXPECTED TO BE VFR...THOUGH PATCHES OF IFR STRATUS WILL STILL BE IN
THE VICINITY UNTIL AROUND 13 UTC. AN UPPER LOW WILL CROSS THE REGION
LATE THIS MORNING AND INTO THE AFTN. THIS WILL TRIGGER SCT TO
NUMEROUS SHRA AND TSTMS IN THE VCNTY OF BOTH AIRFIELDS. THE WINDS
SHOULD TURN OUT OF THE NW AT KHKY BY LATE AFTN AND THE WINDS WILL BE
NW THROUGH THE DAY AT KAVL. DRIER AIR TONIGHT SHOULD LIMIT ANY
RESTRICTIONS TO A BRIEF PERIOD OF MVFR FOG.
ELSEWHERE...200 TO 400 FOOT CIGS SHOULD LIFT INTO THE THE MVFR RANGE
BY 14 UTC AS THE WINDS TURN MORE DOWNSLOPE AT KGMU AND KGSP. AREAS
OF DRIZZLE AND FOG WILL END BY THAT TIME AS WELL. CONDITIONS WILL BE
BETTER AT KAND. SCT TSTMS WILL DEVELOP IN THE VCNTY OF THE AIRFIELDS
THIS AFTN AS AN UPPER LOW CROSSES THE REGION. THE CONVECTION SHOULD
END BY 00 UTC. A COLD FRONT WILL CROSS THE REGION OVERNIGHT. THE
WINDS WILL GRADUALLY TURN OUT OF THE WEST AND THEN NORTHWEST
OVERNIGHT. THE WINDS WILL INCREASE A LITTLE OUT OF THE NE BY SUNRISE
WED.
OUTLOOK...GENERALLY DRY CONDITIONS ARE NOW EXPECTED BEHIND A COLD
FRONT WEDNESDAY THROUGH SATURDAY. HOWEVER...ISOLATED AFTERNOON TSTMS
WILL DEVELOP OVER THE MTNS EACH DAY...WHICH COULD HAVE SOME AFFECT
ON OPERATIONS AT KAVL.
AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE
PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE
CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)...
WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...NED
NEAR TERM...MCAVOY
SHORT TERM...NED
LONG TERM...NED
AVIATION...MCAVOY
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1040 AM CDT TUE JUN 12 2012
.UPDATE...
UPDATE TO ADJUST POPS FOR THE REMAINDER OF TODAY.
&&
.DISCUSSION...
A COLD FRONT IS CURRENTLY STRETCHED ACROSS NORTHERN PORTIONS OF
THE MID SOUTH THIS MORNING. A DECAYING MESOSCALE CONVECTIVE SYSTEM
(MCS) WILL CONTINUE TO WEAKEN WITH RAIN CHANCES DIMINISHING SLOWLY
ACROSS THE SOUTH. WEAK SHORTWAVE DISTURBANCES EMBEDDED WITHIN
NORTHWEST FLOW ALOFT COMBINED WITH THE SOUTHWARD MOVING FRONT AND
AFTERNOON SURFACE HEATING MAY ALLOW FOR THE REDEVELOPMENT OF
SCATTERED SHOWERS AND THUNDERSTORMS ACROSS EASTERN ARKANSAS AND
NORTHERN MISSISSIPPI THIS AFTERNOON. AS INSTABILITY INCREASES
CANNOT RULE OUT A STRONGER THUNDERSTORM...BUT THINK THE POTENTIAL
FOR ANY SEVERE STORMS IS LOW AS SHEAR IS QUITE WEAK.
UPDATED ZONES...GRIDS...AND HWO WILL BE SENT SHORTLY.
JLH
&&
.PREV DISCUSSION... /ISSUED 300 AM CDT TUE JUN 12 2012/
A COLD FRONT CURRENTLY STRETCHES FROM NEAR MOUNT VERNON ILLINOIS
TO NEAR LITTLE ROCK ARKANSAS. CONVECTION THAT OCCURRED EARLIER
THIS EVENING HAS PUSHED ALL THE WAY TO THE GULF COAST. SOME
REDEVELOPMENT IS OCCURRING ACROSS SOUTHERN ARKANSAS IN RESPONSE TO
A SHORTWAVE. THE MOVEMENT OF THESE STORMS ARE TO THE SOUTHEAST
WHICH MOVES THEM INTO PHILLIPS COUNTY ARKANSAS AND PORTIONS OF
NORTHWEST MISSISSIPPI. MODELS INDICATE FURTHER DEVELOPMENT COULD
OCCUR TODAY ALONG AND AHEAD OF THE FRONT. HOWEVER THERE IS SOME
QUESTION ON HOW WORKED OVER THE ATMOSPHERE IS FROM THIS EVENINGS
CONVECTION. THE AREA WILL NOT BE AS UNSTABLE TODAY AS YESTERDAY
AHEAD OF THE FRONT. THE 00Z NAM INDICATES SOME REDEVELOPMENT COULD
OCCUR THIS MORNING ACROSS NORTH MISSISSIPPI BUT SHOULD PUSH SOUTH
OF THE CWA BY EARLY AFTERNOON. THE LATEST RUC AND HRRR RUN SHOWS
SOMETHING SIMILAR TO THE NAM. THE 00Z GFS DID NOT INITIALIZE WELL
WITH WHAT IS CURRENTLY GOING THUS WILL NOT BE USED IN THE SHORT
TERM. THUS WILL LOWER CHANCES FOR SHOWERS AND THUNDERSTORMS TO 40
PERCENT ACROSS MUCH OF NORTH MISSISSIPPI FOR MAINLY THIS MORNING
WITH POSSIBLY LEAVING LIKELY POPS ACROSS PHILLIPS COUNTY AND
PORTIONS OF NORTHWEST MISSISSIPPI THROUGH 7 AM. ELSEWHERE...WILL
REMOVE MENTION OF PRECIPITATION. DRIER AIR WILL BEGIN TO FILTER
INTO NORTHERN PORTIONS OF THE CWA BY THIS AFTERNOON. HIGHS WILL BE
IN THE UPPER 80S.
TONIGHT THROUGH THURSDAY NIGHT...HIGH PRESSURE WILL BUILD INTO THE
AREA FROM THE OHIO VALLEY. DRIER AIR WILL FILTER INTO THE AREA BUT
DO NOT EXPECT MUCH CHANGE IN AT LEAST HIGH TEMPERATURES. HIGHS WILL
STILL BE IN THE MID 80S TO AROUND 90 THROUGH THE PERIOD. LOWS WILL
BE COOLER WITH READINGS IN THE MID 50S TO MID 60S...POSSIBLY A TAD
WARMER THURSDAY NIGHT AS WINDS TURN AROUND TO THE SOUTH.
FRIDAY THROUGH EARLY NEXT WEEK...UPPER RIDGE MOVES OVER THE
MIDSOUTH. 00Z GFS INDICATES DIURNAL HEATING COULD KICK OFF ISOLATED
SHOWERS AND THUNDERSTORMS FRIDAY INTO THE WEEKEND. 00Z ECMWF
SHOWS SOMETHING SIMILAR. FRIDAY SEEMS A LITTLE EARLY FOR MOISTURE
RETURN TO BE ENOUGH TO CAUSE DIURNAL CONVECTION THUS WILL REMOVE POPS.
OTHERWISE...WILL LEAVE CURRENT FORECAST AS IS.
KRM
&&
.AVIATION...
12Z TAF SET
A COLD FRONT HAS MOVED THROUGH JBR AND IS CURRENTLY APPROACHING
MEM AND MKL. WINDS WILL BE NORTHERLY BEHIND AND FRONT TODAY WITH
DRY CONDITIONS. FARTHER SOUTH...A FEW SHOWERS WILL LIKELY DEVELOP
AROUND TUP. ONGOING CONVECTION LOOKS LIKE IT WILL STAY TO THE
SOUTH AND EAST OF TUP...SO WITHOUT ANY ONGOING STORM TO BASE
TIMING ON...JUST INCLUDED VCSH AFTER 16Z. ALL PRECIP WILL END
TONIGHT AND HIGH PRESSURE WILL BUILD ACROSS THE MIDSOUTH RESULTING
IN VFR CONDITIONS AREA WIDE.
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 87 65 86 66 / 40 10 0 0
MKL 87 59 84 57 / 10 10 0 0
JBR 88 61 86 61 / 10 10 0 0
TUP 84 63 87 62 / 60 10 10 10
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
625 AM CDT TUE JUN 12 2012
.UPDATE...AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 300 AM CDT TUE JUN 12 2012/
A COLD FRONT CURRENTLY STRETCHES FROM NEAR MOUNT VERNON ILLINOIS
TO NEAR LITTLE ROCK ARKANSAS. CONVECTION THAT OCCURRED EARLIER
THIS EVENING HAS PUSHED ALL THE WAY TO THE GULF COAST. SOME
REDEVELOPMENT IS OCCURRING ACROSS SOUTHERN ARKANSAS IN RESPONSE TO
A SHORTWAVE. THE MOVEMENT OF THESE STORMS ARE TO THE SOUTHEAST
WHICH MOVES THEM INTO PHILLIPS COUNTY ARKANSAS AND PORTIONS OF
NORTHWEST MISSISSIPPI. MODELS INDICATE FURTHER DEVELOPMENT COULD
OCCUR TODAY ALONG AND AHEAD OF THE FRONT. HOWEVER THERE IS SOME
QUESTION ON HOW WORKED OVER THE ATMOSPHERE IS FROM THIS EVENINGS
CONVECTION. THE AREA WILL NOT BE AS UNSTABLE TODAY AS YESTERDAY
AHEAD OF THE FRONT. THE 00Z NAM INDICATES SOME REDEVELOPMENT COULD
OCCUR THIS MORNING ACROSS NORTH MISSISSIPPI BUT SHOULD PUSH SOUTH
OF THE CWA BY EARLY AFTERNOON. THE LATEST RUC AND HRRR RUN SHOWS
SOMETHING SIMILAR TO THE NAM. THE 00Z GFS DID NOT INITIALIZE WELL
WITH WHAT IS CURRENTLY GOING THUS WILL NOT BE USED IN THE SHORT
TERM. THUS WILL LOWER CHANCES FOR SHOWERS AND THUNDERSTORMS TO 40
PERCENT ACROSS MUCH OF NORTH MISSISSIPPI FOR MAINLY THIS MORNING
WITH POSSIBLY LEAVING LIKELY POPS ACROSS PHILLIPS COUNTY AND
PORTIONS OF NORTHWEST MISSISSIPPI THROUGH 7 AM. ELSEWHERE...WILL
REMOVE MENTION OF PRECIPITATION. DRIER AIR WILL BEGIN TO FILTER
INTO NORTHERN PORTIONS OF THE CWA BY THIS AFTERNOON. HIGHS WILL BE
IN THE UPPER 80S.
TONIGHT THROUGH THURSDAY NIGHT...HIGH PRESSURE WILL BUILD INTO THE
AREA FROM THE OHIO VALLEY. DRIER AIR WILL FILTER INTO THE AREA BUT
DO NOT EXPECT MUCH CHANGE IN AT LEAST HIGH TEMPERATURES. HIGHS WILL
STILL BE IN THE MID 80S TO AROUND 90 THROUGH THE PERIOD. LOWS WILL
BE COOLER WITH READINGS IN THE MID 50S TO MID 60S...POSSIBLY A TAD
WARMER THURSDAY NIGHT AS WINDS TURN AROUND TO THE SOUTH.
FRIDAY THROUGH EARLY NEXT WEEK...UPPER RIDGE MOVES OVER THE
MIDSOUTH. 00Z GFS INDICATES DIURNAL HEATING COULD KICK OFF ISOLATED
SHOWERS AND THUNDERSTORMS FRIDAY INTO THE WEEKEND. 00Z ECMWF
SHOWS SOMETHING SIMILAR. FRIDAY SEEMS A LITTLE EARLY FOR MOISTURE
RETURN TO BE ENOUGH TO CAUSE DIURNAL CONVECTION THUS WILL REMOVE POPS.
OTHERWISE...WILL LEAVE CURRENT FORECAST AS IS.
KRM
.AVIATION...
12Z TAF SET
A COLD FRONT HAS MOVED THROUGH JBR AND IS CURRENTLY APPROACHING
MEM AND MKL. WINDS WILL BE NORTHERLY BEHIND AND FRONT TODAY WITH
DRY CONDITIONS. FARTHER SOUTH...A FEW SHOWERS WILL LIKELY DEVELOP
AROUND TUP. ONGOING CONVECTION LOOKS LIKE IT WILL STAY TO THE
SOUTH AND EAST OF TUP...SO WITHOUT ANY ONGOING STORM TO BASE
TIMING ON...JUST INCLUDED VCSH AFTER 16Z. ALL PRECIP WILL END
TONIGHT AND HIGH PRESSURE WILL BUILD ACROSS THE MIDSOUTH RESULTING
IN VFR CONDITIONS AREA WIDE.
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 88 65 86 66 / 20 10 0 0
MKL 88 59 84 57 / 10 10 0 0
JBR 89 61 86 61 / 10 10 0 0
TUP 87 63 87 62 / 40 10 10 10
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
654 AM CDT TUE JUN 12 2012
.AVIATION...
FOR THE 12Z TAFS...ONGOING SHOWERS AND TSTMS AT KAMA WILL CONTINUE
UNTIL AROUND MID MORNING. MAJORITY OF PRECIPITATION SHOULD BYPASS
KDHT AND KGUY THIS MORNING. A LULL IN THE SHOWERS AND TSTMS IS
EXPECTED BY EARLY THIS AFTERNOON. NEXT ROUND OF STORMS TO DEVELOP
SOMETIME LATE THIS AFTERNOON OR EVENING...DEPENDING ON HOW LONG IT
TAKES THE ATMOSPHERE TO RECOVER FROM MORNING TSTMS. FOR THIS
REASON... HAVE DECIDED NOT TO INSERT TSTMS AT ANY TAF SITE AFTER THIS
MORNING DUE TO LOW CONFIDENCE IN HOW MESOSCALE SITUATION WILL EVOLVE
LATER TODAY AND TONIGHT. FUTURE SHIFTS MAY NEED TO CONSIDER ADDING
TSTMS TO ONE OR MORE OF THE TAFS IF CONDITIONS BECOME MORE CLEAR CUT.
ANDRADE
&&
.PREV DISCUSSION... /ISSUED 444 AM CDT TUE JUN 12 2012/
DISCUSSION...
AN ACTIVE AND WET WX PATTERN IS TAKING SHAPE ACROSS THE AREA AS
FIRST ROUND OF SHOWERS AND THUNDERSTORMS ARE CURRENTLY MOVING ACROSS
PORTIONS OF THE FA. THESE STORMS WERE BECOMING MORE UPSCALE AS THEY
ENCOUNTER A MORE BUOYANT AIR MASS PER LAPS AND RAP DATA INDICATING
MUCAPES AROUND 200-600 J/KG. DIVERGENCE PROVIDED BY THE RRQ OF A JET
STREAK AND LFQ OF A JET STREAK NOSING INTO THE PANHANDLES ARE ALSO
HELPING TO INTENSIFY THESE STORMS. THESE STORMS WILL CONTINUE
THROUGH THE NEXT FEW HOURS WHERE 0-6 KM BULK SHEAR AROUND 30-40 KTS
AND STEEP MID-LEVEL LAPSE RATES CAN RESULT IN SOME OF THESE STORMS
TO BECOME SEVERE.
LATER TODAY...EXPECT A BIT OF A LULL IN THUNDERSTORM ACTIVITY ONCE
THIS EARLY MORNING CONVECTION EXITS THE AREA. HOWEVER SUFFICIENT LOW-
LEVEL MOISTURE WILL BE MAINTAINED ACROSS THE AREA ON BREEZY SOUTHEAST
SURFACE WINDS. SEVERAL UPPER-LEVEL DISTURBANCES WILL ALSO TRAVERSE
THE SOUTHERN PLAINS TODAY PROVIDING WEAK UPPER LIFT WHILE ANY
OUTFLOW BOUNDARIES CAN PROVIDE A FOCUS FOR STORM DEVELOPMENT.
FORECAST SOUNDINGS INDICATE THE AIR MASS WILL BE VERY UNSTABLE WITH
MLCAPES AROUND 2000-3000 J/KG. SHEAR WILL REMAIN MORE THAN ADEQUATE
TO ALLOW SOME STORMS TO BECOME SEVERE AND EXPECT THE MAIN SEVERE
THREATS TO BE LARGE HAIL AND STRONG WINDS. CONVECTION WILL BECOME
MORE WIDESPREAD TONIGHT AS A LOW-LEVEL JET SETTING UP ACROSS THE
SOUTHERN PLAINS WILL HELP TO MAINTAIN AND WARM...MOIST...AND
UNSTABLE AIR MASS ACROSS THE AREA. HIGHS TODAY SHOULD BE A LITTLE
COOLER...IN THE 80S.
ON WEDNESDAY THE SURFACE FLOW WILL TREND MORE TO THE SOUTH AS A COLD
FRONT THAT IS CURRENTLY SOUTH OF THE AREA LIFTS NORTH. WEAK MID-
LEVEL RIDGING WILL BUILD ACROSS THE SOUTHERN PLAINS HOWEVER SEVERAL
UPPER DISTURBANCES WILL QUICKLY BREAK DOWN THE RIDGE. MOIST AND
UNSTABLE CONDITIONS WILL REMAIN ACROSS THE AREA SO WILL CONTINUE
CHANCE POPS IN THE FORECAST. HAVE ALSO CONTINUED MENTION OF THUNDER
IN THE FORECAST THROUGH THE WEEKEND AS THE DRYLINE SHOULD REMAIN
WEST OF THE AREA WHILE SOUTHWEST UPPER FLOW TAPS INTO THE TROPICAL
MOISTURE OUT OF THE PACIFIC. STILL FAVOR BETTER CHANCES FOR STORMS
TO BE IN THE WEST AND CENTRAL SECTIONS OF THE FA GIVEN THE FORECAST
POSITION OF THE DRYLINE. THE STRENGTHENING OF A LEE TROUGH AND
POSSIBLE EASTWARD MOVEMENT OF THE DRYLINE EARLY NEXT WEEK SHOULD
END THUNDER CHANCES WITH THE NEXT POSSIBLE COLD FRONTAL INTRUSION
COMING AROUND MID-WEEK.
CLK
FIRE WEATHER...
ABUNDANT ATMOSPHERIC MOISTURE AND CHANCES FOR PRECIPITATION THROUGH
MUCH OF THE 7 DAY FORECAST PERIOD WILL PRECLUDE ELEVATED OR CRITICAL
FIRE WEATHER CONDITIONS ACROSS THE TX/OK PANHANDLES.
CLK
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1034 AM CDT TUE JUN 12 2012
.UPDATE...SCATTERED TO BROKEN CUMULUS IS EXPECTED THROUGH THE
AFTERNOON. MAY BE A BIT CLOUDIER NORTH OF MADISON THAN PREVIOUSLY
EXPECTED...BUT OTHERWISE THE FORECAST IS ON TRACK. A GREAT
AFTEROON AHEAD WITH HIGHS IN THE UPPER 60S TO LOW 70S.
&&
.AVIATION/18Z TAFS/...STRATOCUMULUS FIELD IS CURRENTLY PUSHING IN
FROM THE NORTHWEST UNDER COOLER AIR ALOFT. CIGS MAY BREIFLY DROP
TO MVFR THROUGH LATE MORNING...BUT OVERALL EXPECTING INCREASING
MIXING TO RAISE CEILINGS TO VFR. OTHERWISE...FAIR WEATHER
EXPECTED THROUGH WEDNESDAY.
&&
.PREV DISCUSSION... /ISSUED 341 AM CDT TUE JUN 12 2012/
SHORT TERM...
TODAY AND TONIGHT...FORECAST CONFIDENCE MEDIUM TO HIGH.
MAIN ISSUES TODAY ARE AMOUNT OF CLOUD COVER AND TEMPERATURES.
CURRENT IR AND FOG PRODUCT SATELLITE IMAGERY INDICATING MOST OF THE
STRATOCU ASSOCIATED WITH THE COLD AIR ADVECTION WILL REMAIN CLOSE TO
SHORT WAVE TROUGH ACROSS NORTHERN WISCONSIN...BUT THERE IS A POCKET
OF SC FARTHER SOUTH IN CENTRAL MN AHEAD OF WEAK VORT MAX ON WATER
VAPOR LOOPS THAT WILL HAVE TO BE WATCHED...AS NAM AND RAP 925-850MB
RH FORECASTS INDICATE 60 PCT OR MORE CROSSING THE REGION THIS
MORNING INTO THIS AFTERNOON AND BOTH HAVE ENOUGH MOISTURE...THOUGH
SHALLOW...AROUND 4-5K FT ON MODEL SOUNDINGS FOR A BROKEN DECK.
HOWEVER...SFC DEW POINTS ON THOSE SOUNDINGS APPEAR A BIT HIGH...SO
WILL HOLD SKY COVER IN THE 40 PCT RANGE ACROSS THE NORTHERN CWA HAVE
PARTLY CLOUDY
850 MB AND 925 MB TEMPERATURES VERY SIMILAR ON ALL MODELS...THOUGH
00Z ECMWF 925 MB TEMPS ABOUT 2C TO 4C WARMER. WILL TREND TOWARD THE
COOLER BLENDED TEMPS FOR HIGHS IN THE UPPER 60S NORTH AND LOWER 70S
SOUTH.
CLEAR SKIES AND LIGHT WINDS TONIGHT AS SURFACE HIGH CROSSES STATE
WILL ALLOW GOOD RADIATIONAL COOLING CONDITIONS...WITH LOWS IN THE
40S EXPECTED EXCEPT NEAR THE LAKE AND THE FAR SOUTHEAST. FORCING
AHEAD OF NEXT WAVE REMAINS WEST THROUGH 12Z WEDNESDAY...WITH ONLY
THE LEADING EDGE OF MID TO HIGH LEVEL WARM AIR ADVECTION CLOUDS
REACHING THE WESTERN CWA BY MORNING. THE COOL OVERNIGHT LOWS WILL
PRODUCE SOME PATCHY FOG IN THE WI RIVER VALLEY.
WEDNESDAY THROUGH THURSDAY...FORECAST CONFIDENCE HIGH.
HIGH PRESSURE WILL DRIFT ACROSS THE GREAT LAKES REGION THROUGH
THURSDAY. EASTERLY FLOW WILL KEEP LAKESHORE AREAS COOLER THAN INLAND
AREAS. 925MB TEMPS WILL STEADILY INCREASE...UP TO AROUND 20C IN
SOUTH CENTRAL WI BY THU AFTERNOON...YIELDING MAX TEMPS AROUND 80.
DEWPOINT TEMPS SEEM CHARACTERISTICALLY OVERDONE BY THE MODELS GIVEN
THAT THERE IS LIMITED MOISTURE RETURN WITH THE WAA...SO WENT WITH
THE BIAS-CORRECTED LOWER VALUES GENERALLY IN THE 40S.
A 500MB SHORTWAVE IS EXPECTED TO MOVE ACROSS SOUTHERN/CENTRAL WI WED
NIGHT WHICH SHOULD LEAD TO MID CLOUDS OVERHEAD. TOO DRY AND NOT
ENOUGH DEEP LEVEL FORCING FOR ANY PRECIP.
LONG TERM...
FRIDAY THROUGH TUESDAY...FORECAST CONFIDENCE MEDIUM TO HIGH.
THE UPPER LEVEL PATTERN IN THE EXTENDED RANGE FORECAST SHOWS A REX
BLOCK RETROGRADING INTO THE CENTER OF THE COUNTRY. HIGH PRESSURE
RIDGING WILL LIKELY KEEP SOUTHEAST WI ON THE DRY SIDE OF A
STATIONARY FRONTAL BOUNDARY SETTING UP ACROSS CENTRAL/NORTHERN WI.
SEVERAL SHORTWAVES WILL TRACK ALONG THE FRONT DURING THIS
PERIOD...LEADING TO THE SMALL CHANCES FOR THUNDERSTORMS MENTIONED IN
MAINLY SOUTH CENTRAL WI.
THE ECMWF LOOKS A LITTLE TOO PROGRESSIVE WITH BREAKING DOWN THE
RIDGE AND DROPPING THE FRONT THROUGH SOUTHERN WI ALREADY ON TUE. THE
NWS HYDROMETEOROLOGICAL PREDICTION CENTER /HPC/ FAVORS THE SLOWER
SOLUTION OF THE 00Z GFS AND 00Z ECMWF ENSEMBLE MEAN MODEL BLEND.
THIS WOULD KEEP SOUTHERN WI GENERALLY DRY THROUGH TUESDAY.
TEMPS WILL WARM BACK INTO THE MID 80S TO LOWER 90S INLAND FROM LAKE
MICHIGAN WITH PERSISTENT SOUTHERLY FLOW THROUGH MONDAY AND LIKELY
BEYOND.
AVIATION/12Z TAFS/...
LOOKING AT VFR CONDITIONS THROUGH THE FORECAST. MORNING MIXING WILL
BRING MORE CONSISTENT WIND GUSTS IN THE 15 TO 20 KNOT RANGE...EASING
THROUGH THE LATE AFTERNOON AND EVENING AS HIGH PRESSURE SLIDES OVER
STATE. EXPECTING MAINLY SCATTERED STRATOCUMULUS TODAY...THOUGH BASED
ON SATELLITE IMAGERY THERE IS A CHANCE FOR A BROKEN 4-5K FT DECK TO
PASS MAINLY JUST NORTH OF THE TAF SITES THAT WILL HAVE TO BE
MONITORED UP TO ISSUANCE TIME. CLEAR SKIES AND LIGHT WINDS TONIGHT
MAY BRING SOME PATCHY GROUND FOG...BUT POTENTIAL TOO LOW TO MENTION.
BEST CHANCE FOR VSBY REDUCING FOG WILL BE IN THE WI RIVER VALLEY
TONIGHT.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...DDV
TODAY/TONIGHT AND AVIATION/MARINE...REM
WEDNESDAY THROUGH MONDAY...MRC
AREA FORECAST DISCUSSION
NWS CARIBOU ME
703 PM EDT TUE JUN 12 2012
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE WEST TONIGHT AND SLOWLY CROSS
THE REGION ON WEDNESDAY THEN MOVE EAST WEDNESDAY NIGHT. HIGH PRESSURE
FROM NORTHERN CANADA WILL SLOWLY BUILD TOWARD THE REGION THROUGH
THE REMAINDER OF THE WEEK INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
700 PM UPDATE: USING THE RUC MODEL AND RADAR TREND, HAVE DELAYED THE
ONSET OF SHOWERS ACROSS MOST OF THE REGION FROM LATE TONIGHT UNTIL
WEDNESDAY MORNING. ALSO INCREASED CLOUDS A BIT FASTER TONIGHT THAN
PREVIOUS FORECAST BASED ON RH PROGS.
PREVIOUS DISCUSSION: A COLD FRONT CURRENTLY STRETCHING FROM
WESTERN QUEBEC SOUTHWARD THROUGH THE GREAT LAKES WILL CONTINUE TO
TREK EASTWARD TONIGHT AND WILL PASS ACROSS THE STATE TOMORROW.
THIS FEATURE IS PRODUCING A SWATH OF LIGHT TO MODERATE SHOWERS
ACROSS EASTERN NEW YORK AND WESTERN NEW ENGLAND THIS AFTERNOON,
AND THIS TOO WILL SHIFT EASTWARD. PRECIPITATION SHOULD REACH
WESTERN SECTIONS LATE THIS EVENING, BY AROUND MIDNIGHT, BUT IT
WILL BE EARLY TOMORROW MORNING BEFORE IT MAKES IT INTO EASTERN
MAINE. NOT SEEING MUCH EVIDENCE OF SURFACE BASED OR ELEVATED
INSTABILITY OVERNIGHT, SO THERE SHOULDN`T BE ANY THUNDER. HOWEVER
HAVE INCLUDED THE CHANCE OF THUNDERSTORMS TOMORROW AFTERNOON WITH
THE ACTUAL FRONTAL PASSAGE. HEAVY RAIN IS ALSO A POSSIBILITY AS
PWATS WILL BE RUNNING HIGH, 1 TO 1.5+ INCHES, BUT GIVEN THAT THIS
SYSTEM WILL BE WEAKENING AS IT MOVES THROUGH HAVE OPTED TO NOT
INCLUDE HEAVY RAIN IN THE FORECAST FOR NOW. RAINFALL TOTALS WILL
BE HIGHEST IN CENTRAL AND WESTERN MAINE, WHERE 0.50 TO 0.75 INCHES
ARE EXPECTED THROUGH EARLY TOMORROW EVENING. AMOUNTS DROP OFF AS
YOU MOVE SOUTH AND EAST, WITH A TENTH TO A THIRD OF AN INCH ACROSS
EASTERN AND DOWNEAST MAINE. OVERNIGHT LOWS WILL BE MILD GIVEN THE
INFLUX OF MOISTURE, WITH MOST LOCATIONS DROPPING INTO THE MID AND
UPPER 50S. TOMORROW WILL BE MUCH COOLER THAN THE PREVIOUS COUPLE
OF DAYS; HIGHS ARE EXPECTED TO BE IN THE MID AND UPPER 60S.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
MODELS APPEAR TO REASONABLY CONSISTENT WITH THE DEPARTURE TIME OF
SHWRS E OF THE FA WED NGT WITH MAX THU 00-06Z QPF MSLY LESS THAN
0.10 INCHES FOR LOCATIONS EXPERIENCING RNFL...WITH ALL LOCATIONS
DRYING BY THU MORN. WITH WINDS BECOMING N AT 5 TO 10 MPH BEHIND
A COLD FRONT LATE WED NGT AND ERLY THU MORN...CURRENT THINKING IS
THAT THERE WILL NOT BE MUCH TM FOR PATCHY FOG TO FORM IN THE WAKE
OF RNFL...SO FOR NOW WE DID NOT INCLUDE ANY FOG IN THE GRIDS FOR
THIS PD...BUT BRIEF FOG CANNOT BE COMPLETELY RULED FOR A FEW
LOCATIONS.
OTHERWISE...MODELS HAVE BACKED OFF OF KEEPING CLDNSS AND ASSOCIATED
SHWRS WITH THE UPPER LOW SE OF NOVA SCOTIA ACROSS SRN PTNS OF THE
FA THU INTO THU NGT...SO WE LOWERED POPS BLO SLGT CHC AND ALLOWED
FOR AT LEAST PARTIAL CLRG.
WITH HI PRES BOTH AT THE SFC ALD ALF SLOWLY SUBSIDING SWRD FROM
NRN/CNTRL CAN...FAIR SKIES AND LGT WINDS WILL CONT INTO FRI. LOW
AND HI TEMPS WED NGT THRU THU NGT SHOULD BE NEAR NORMAL FOR THIS
TM OF SEASON...WITH A SLIGHT WARMING TREND BEGINNING ON FRI.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
A STRONG RIDGE OF HIGH PRESSURE IS EXPECTED TO REMAIN ACROSS THE
NORTHEAST THIS WEEKEND THROUGH MUCH OF NEXT WEEK BRING EXCEPTIONALLY
WARM WEATHER TO THE REGION. AFTER A CLEAR NIGHT FRIDAY
NIGHT...SATURDAY IS EXPECTED TO BE SUNNY WITH HIGH PRESSURE BOTH AT
THE SURFACE AND ALOFT CRESTING OVER THE AREA. THE HIGH WILL REMAIN
IN PLACE ON SUNDAY BRINGING ANOTHER MOSTLY SUNNY AND VERY WARM DAY.
CLOUDS MAY INCREASE LATE IN THE DAY AS A WEAK SHORTWAVE SLIDES
ACROSS THE NORTH AND SOME SCATTERED LATE DAY SHOWERS OR
THUNDERSHOWERS ARE POSSIBLE ACROSS THE NORTH. SURFACE HIGH PRESSURE
WILL THEN SLIDE SOUTH OF THE AREA EARLY NEXT WEEK. SOUTHWESTERLY
WINDS JUST NORTH OF THE HIGH WILL THEN CHANNEL VERY WARM AIR INTO
THE NORTHEAST FROM THE MIDWEST. THE WEAK DISTURBANCE OVER THE FAR
NORTH MAY BRING SOME SHOWERS OR THUNDERSHOWERS ACROSS THE NORTH
MONDAY INTO TUESDAY. OTHERWISE...THE DAYS WILL BE PARTLY
CLOUDY...WARM AND HUMID. THE WARMEST AIR MAY THEN REACH THE STATE
DURING MID WEEK WHEN TEMPS ON WEDNESDAY AND AGAIN ON THURSDAY COULD
SOAR WELL INTO THE 80S AND POSSIBLY REACH 90 OR HIGHER IN SOME AREAS
UNDER MOSTLY SUNNY SKIES.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
NEAR TERM: VFR CEILINGS WILL LOWER TO MVFR CEILING AFTER MIDNIGHT,
AND REMAIN MVFR IN RAIN SHOWERS WEDNESDAY. CEILINGS WILL REMAIN
MVFR THROUGH THE REMAINDER OF THE DAY AND MAY OCCASIONALLY DIP
BELOW 1000 FT IN HEAVIER SHOWERS. SCATTERED THUNDERSTORMS ARE
POSSIBLE WEDNESDAY AFTERNOON.
SHORT TERM: ALL SITES WILL INITIALLY BEGIN MVFR WITH LOW CLGS AND
OCNL VSBYS BETWEEN 3 TO 6 SM IN SHWRS WED EVE AND THEN IMPROVE TO
VFR BY THU MORN BEHIND A COLD FRONT. ALL SITES SHOULD THEN CONT
VFR THRU SUN.
&&
.MARINE...
NEAR TERM: A COLD FRONT WILL APPROACH THE WATERS LATE TONIGHT AND
MOVE ACROSS THE AREA LATE TOMORROW. WHILE WINDS AND WAVES WILL
INCREASE IN RESPONSE, THEY ARE EXPECTED TO REMAIN BELOW SMALL
CRAFT LEVELS. THEREFORE, NO HEADLINES ARE NEEDED.
SHORT TO LONG TERM: BOTH WINDS AND SEAS WILL REMAIN BLO SCA
CRITERIA THRU SUN...WITH WINDS INCREASING TO 10 TO 15 KT FROM
THE N BEHIND A COLD FRONT THU INTO THU NGT...THEN GRADUALLY
DIMINISHING FRI INTO THE WEEKEND. USED A BLEND OF NAM12...GFS40
AND GMOS FOR WINDS AND KEPT CLOSE TO WW3 WV GUIDANCE FOR WV HTS...
LOWERED FOR BAYS IMMEDIATELY ADJACENT TO THE COAST.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...FOSTER/HASTINGS
SHORT TERM...VJN
LONG TERM...BLOOMER
AVIATION...FOSTER/HASTINGS
MARINE...FOSTER/HASTINGS/VJN
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
325 PM EDT TUE JUN 12 2012
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 325 PM EDT TUE JUN 12 2012
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW PROGRESSIVE UPR
TROF EXTENDING FM HUDSON BAY INTO THE GRT LKS MOVING E IN ADVANCE OF
UPR RDG OVER WRN CANADA. SHRTWV EMBEDDED WITHIN THIS TROF BROUGHT
LOTS OF CLDS AND SOME -SHRA TO MAINLY THE NRN TIER INTO EARLY
AFTN... BUT TREND THIS AFTN HAS BEEN FOR MORE SUNSHINE AS DNVA/
LARGER SCALE QVECTOR DVGC/MORE ACYC FLOW AND DRIER AIR SHOWN ON THE
12Z INL RAOB IS FOLLOWING IN THE WAKE OF THAT DISTURBANCE IN ADVANCE
OF SFC HI PRES CENTERED OVER SE SDAKOTA. SKIES ARE MOCLR FM THE HI
CENTER STRETCHING TOWARD LK WINNIPEG...WHERE THE 12Z RAOB AT THE PAS
IN MANITOBA SHOWS A PWAT OF 0.28 INCH. SFC DEWPTS THIS AFTN HAVE
MIXED OUT INTO THE LO-MID 30S IN THIS UPSTREAM AIRMASS. MORE CLDS
ARE PRESENT A BIT FARTHER W IN THE NRN PLAINS IN THE RETURN SW FLOW
ARND THE SFC HI AND IN ADVANCE OF SHRTWV TRACKING E ACRS
WYOMING/MONTANA. 12Z BIS RAOB SHOWS MORE MSTR/PWAT OF 0.70 INCH NEAR
THE WAD CLD BAND.
MAIN FCST CONCERNS IN THE SHORT TERM REVOLVE ARND CLRG TRENDS THIS
AFTN AND THEN TEMPS/POTENTIAL FOR FROST TNGT.
TNGT...SFC HI PRES IS FCST TO MOVE E AND TO OVER NRN LWR MI BY 12Z
WED. EXPECT ANY LINGERING CLDS TO DSPT LATE THIS AFTN/EARLY THIS
EVNG WITH THE ARRIVAL OF MORE ACYC FLOW AND WARMER/DRIER AIR AT
H925. STRONGER WSW FLOW ARND SFC HI IS FCST TO DVLP OVER THE NW HALF
OF THE CWA AFT 06Z...WITH PWAT RISING AS THIS FLOW TAPS MORE MSTR
SHOWN ON THE 12Z BIS RAOB. MOST SUSTAINED CONDITIONS FOR RADIATIONAL
COOLING LOOK TO BE OVER THE SCNTRL AND E...WHERE THE GRADIENT FLOW
WL REMAIN WEAKER/PWAT LOWER AND UNDER 0.5 INCH THRU 12Z WED. OPTED
TO EXTEND GOING FROST ADVY NEAR THE WI BORDER TO INCLUDE MOST OF THE
CWA FROM BARAGA TO THE E...WITH MIN TEMPS CLOSER TO THE LOWER END OF
GUIDANCE IN THESE AREAS PER OBSVD MIXING OF DEWPTS UPSTREAM.
WED...AS SFC HI PRES DRIFTS SLOWLY E ACRS LK HURON...STRONGER SW
FLOW WL DVLP OVER THE ENTIRE CWA. WITH APRCH OF DISTURBANCE NOW
MOVING THRU THE NRN PLAINS AND SOME MSTR RETURN...EXPECT AT LEAST
SOME CLDS TO INVADE MAINLY THE WRN ZNS IN THE AFTN. ALTHOUGH THE GFS
GENERATES SOME PCPN OVER THE FAR W LATE IN THE DAY...PREFER TO
FOLLOW THE DRY 12Z NAM/CNDN/LOCAL WRF-ARW DUE TO VERY DRY NATURE OF
LLVL AIRMASS. MIXING TO H8 ON NAM FCST SDNGS YIELDS HI TEMPS
REBOUNDING TO 70 TO 75 AWAY FM LK MODERATION.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 325 PM EDT TUE JUN 12 2012
THE WEAK HIGH PRESSURE RIDGE IN PLACE FOR WEDNESDAY WILL SLIDE
EASTWARD AS A TROUGH OVER THE CANADIAN PRAIRIE DIGS DOWN INTO THE
NORTHERN PLAINS. MODELS AGREE THAT A SHORTWAVE WILL BE APPROACHING
WESTERN UPPER MICHIGAN BY 00Z THURSDAY...THOUGH THERE SEEMS TO BE
DIFFERENCES WITH HOW STRONG IT WILL BE. THE GEM/ECMWF SEEM TO AGREE
ON A WEAKER SOLUTION...WHILE THE GFS DEVELOPS A SMALL TROUGH. THE
GFS ALSO AMPLIFIES THE EXITING RIDGE MUCH MORE THAN THE OTHER
MODELS. WILL STICK WITH A BLEND MORE SIMILAR TO THE GEM/ECMWF FOR
NOW GIVEN THEIR AGREEMENT...THOUGH CONFIDENCE IS NOT VERY HIGH. THIS
KEEPS MOST OF THE PRECIPITATION THAT WILL OCCUR WITH THIS SHORTWAVE
OVER WESTERN LAKE SUPERIOR AND THE WEST HALF OF THE CWA. WILL KEEP
LOW CHANCE POPS OVER THESE AREAS TO ACCOUNT FOR UNCERTAINTY DURING
THE DAY ON THURSDAY. MODEL SOUNDINGS SUGGEST MIXING TO AROUND
850MB...WHICH PUTS HIGHS IN THE 70S AND PERHAPS LOW 80S. DESPITE
INCOMING CLOUD COVER WITH THE SHORTWAVE...EXPECT THE WARMEST
TEMPERATURES TO BE OUT WEST WITH THE HIGHEST 850MB TEMPS OF AROUND
13C. WITH SKIES MOSTLY SUNNY OUT EAST...EXPECT MIXING TO BRING
RELATIVE HUMIDITY DOWN INTO THE 30 PERCENT RANGE. WITH THE STRONGER
PRESSURE GRADIENT ASSOCIATED WITH THE LOW PRESSURE SYSTEM...EXPECT
GUSTY SOUTHERLY TO SOUTHEASTERLY WINDS ACROSS MUCH OF THE
AREA...MAINLY NORTH CENTRAL AND OVER LAKE SUPERIOR. HIGHEST GUSTS
ARE EXPECTED TO BE AROUND 25 KNOTS.
FRIDAY THE TROUGH WILL SWING JUST NORTH OF LAKE SUPERIOR...REACHING
HUDSON BAY BY 00Z SATURDAY. MODELS SEEM TO BE IN FAIRLY GOOD
AGREEMENT ON THE AMOUNT OF QPF ASSOCIATED WITH THE PASSING FRONT
ACROSS WEST AND CENTRAL UPPER MICHIGAN...WITH AROUND 0.25-0.50 INCH
IMPACTING THE AREA. THE NAM BRINGS THE FRONT ALL THE WAY THROUGH THE
CWA...BRINGING 0.25 INCH TO THE EASTERN AREAS. THE ECMWF/GEM/GFS
TAKE THE BEST UPPER LEVEL FORCING NORTHWARD /PER 850-500MB QVECTOR
CONVERGENCE/ AND THEREFORE KEEP MUCH OF THE EASTERN CWA DRY. THERE
ARE ALSO DIFFERENCES IN TIMING OF PRECIPITATION...SO HAVE LOWERED
CONFIDENCE IN PUTTING SPECIFICS INTO THE FORECAST. KEPT THE BEST
CHANCES OVER LAKE SUPERIOR AND ACROSS THE WEST AND CENTRAL. MU/ML
CAPE VALUES THURSDAY NIGHT INTO FRIDAY AFTERNOON RANGE FROM AROUND
200-1000 J/KG...SO KEPT THUNDER CHANCES IN. WITH PRESSURE GRADIENT
REMAINING TIGHT...WINDS WILL CONTINUE TO GUST INTO THE 20-25 KNOT
RANGE THROUGH FRIDAY EVENING.
FOR THE EXTENDED /THE WEEKEND INTO TUESDAY/...
FOR THE MOST PART...IT SEEMS THROUGH THE WEEKEND A RIDGE WILL CENTER
ITSELF OVER LOWER MICHIGAN...AND SHORTWAVES WILL RIDE AROUND THE
IT BRINGING CHANCES OF PRECIPITATION. FOR THE FIRST PART OF THE
WORK WEEK...A STRONGER LOW PRESSURE TROUGH WILL SWING INTO THE
NORTHERN PLAINS AND BRING ADDITIONAL PRECIPITATION/THUNDERSTORMS TO
MUCH OF THE CWA. HOWEVER...MODELS DIFFER ON TIMING AND PLACEMENT OF
FEATURES. THE GFS/GEM BRING A STRONGER RIDGE UP FROM THE
PLAINS...KEEPING MUCH OF THE PRECIPITATION ASSOCIATED WITH A SECOND
TROUGH/SHORTWAVE CONFINED TO THE WESTERN CWA OR NOT IN THE UPPER
PENINSULA AT ALL. THE GFS EVENTUALLY DEVELOPS THE TROUGH INTO A
CLOSED LOW...AND THEN MOVES THE PRECIPITATION THROUGH ON MONDAY. THE
ECMWF KEEPS THE RIDGE FURTHER SOUTH AND EAST...AND BRINGS A MUCH
MORE POTENT SHORTWAVE INTO UPPER MICHIGAN SATURDAY MORNING INTO
MONDAY. WITH SUCH A VARIANCE IN SOLUTIONS...DO NOT FEEL CONFIDENT
BUMPING UP ANY POPS. WILL KEEP THE MENTION OF THUNDER AS MODELS SEEM
TO BRING IN A DECENT AMOUNT OF INSTABILITY THROUGH THE WEEKEND. AS
FOR HIGH TEMPERATURES...850MB TEMPS LOOK TO BE IN THE 16-18C
RANGE...SO WILL KEEP FORECASTED HIGHS IN THE UPPER 70S TO THE MID
80S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 124 PM EDT TUE JUN 12 2012
ALTHOUGH SOME LOWER CLDS/MVFR CIGS MAY LINGER EARLY AT SAW...THE
ARRIVAL OF HI PRES/DRIER AIR WL BRING VFR CONDITIONS THE REST OF
THIS FCST PERIOD. GUSTY NW WINDS THIS AFTN WL ALSO DIMINISH BY TNGT
WITH THE WEAKER PRES GRADIENT/LOSS OF DAYTIME HEATING. EXPECT A
STRONGER SW FLOW TO DVLP ON WED ONCE THE HI CENTER SHIFTS TO THE E
OVER NRN LOWER MI.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 325 PM EDT TUE JUN 12 2012
EXPECT NW WINDS UP TO 25-30 KTS INTO THIS EVENING OVER THE E TO
DIMINISH OVERNIGHT WITH THE ARRIVAL OF A HI PRES RIDGE. THESE LIGHT
WINDS WILL PERSIST INTO WED NIGHT AS THE HI REMAINS DOMINANT. THEN A
STRONGER S WIND UP TO 25 KTS WILL IMPACT MAINLY THE NCENTRAL AND E
PART OF THE LAKE ON THU/FRI UNDER A TIGHTER PRES GRADIENT BETWEEN
THE HI DEPARTING TO THE E AND A LO PRES TROF APPROACHING FROM THE W.
THEN LIGHTER WINDS WILL PREVAIL AGAIN THIS COMING WEEKEND WITH A
WEAKER PRES GRADIENT FORECAST TO DOMINATE THE UPPER LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
FROST ADVISORY FROM 1 AM EDT /MIDNIGHT CDT/ TO 7 AM EDT /6 AM
CDT/ WEDNESDAY FOR MIZ002-004>007-009>014-084-085.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...MCB
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
125 PM EDT TUE JUN 12 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 602 AM EDT TUE JUN 12 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A FAIRLY DEEP TROF
EXTENDING FROM HUDSON BAY TO THE UPPER GREAT LAKES. ONE VORT MAX IS
MOVING ACROSS LAKE SUPERIOR/UPPER MI ATTM AND ANOTHER WEAKER VORT
MAX IS DROPPING SE INTO NRN MN. AT THE SFC...COLD FRONT HAS CLEARED
THE FCST AREA...AND STRONG CAA IS UNDERWAY. 850MB TEMPS WHICH WERE
RUNNING 10-16C AT 00Z SHOULD BE DOWN TO 0 TO 2C AT 18Z TODAY.
WITH 850MB THERMAL TROF ARRIVING BY MID DAY...EXPECT PLENTY OF CLOUD
COVER THRU THE MORNING HRS. SECONDARY SHORTWAVE BRUSHING THE AREA
MIGHT BRING A FEW -SHRA/SPRINKLES ACROSS THE N AS WELL. THERE HAVE
BEEN OCNL REPORTS OF LIGHT PCPN IN NRN MN DURING THE NIGHT. CLOUDS
SHOULD SLOWLY BEGIN TO BREAK UP FROM W TO E DURING THE AFTN. MODELS
ARE FAIRLY AGGRESSIVE WITH THE DRYING/CLEARING TREND. MIGHT BE A BIT
TOO QUICK GIVEN PROXIMITY OF THERMAL TROF DURING THE LATTER PORTION
OF THE DAY. UNDER CLOUDS/CAA...TEMPS SHOULD RISE VERY LITTLE THIS
MORNING. IN FACT...TEMPS OVER THE E MAY FALL A FEW DEGREES DURING
THE MORNING...ESPECIALLY CLOSE TO LAKE SUPERIOR. DURING THE AFTN...
TEMPS MAY NOT GET OUT OF THE UPPER 40S E OF MUNISING GIVEN CHILLY
AIR MASS AND STRONG GRADIENT FLOW ACROSS THE LAKE. ELSEWHERE...TEMPS
WILL BEGIN TO RISE DURING THE AFTN AS CLOUDS SLOWLY BEGIN TO BREAK
UP FROM W TO E. WITH EXPECTATION OF SOME SUN...UPPER 50S/LWR 60S
SHOULD GENERALLY BE THE RULE. MAY REACH THE MID 60S OVER THE SCNTRL.
COLD AIR ARRIVING TODAY WILL SET THE STAGE FOR A CHILLY/POSSIBLY
FROSTY NIGHT TONIGHT. WITH SFC HIGH PRES MOVING INTO THE VCNTY...
WINDS WILL DROP TO CALM/NEAR CALM. DRY AIR MASS (PRECIPITABLE WATER
35 TO 50PCT OF NORMAL THRU AT LEAST THE FIRST HALF OF THE NIGHT)
WILL ALLOW FOR STRONG RADIATIONAL COOLING UNDER CLEAR SKIES. RIGHT
NOW...IT APPEARS GREATEST COVERAGE OF FROST WILL BE OVER THE
INTERIOR W HALF TOWARD THE WI BORDER. HAVE THUS OPTED FOR A FROST
ADVY FOR GOGEBIC/IRON/DICKINSON LATE TONIGHT. MAY NEED TO EXPAND
ADVY EASTWARD IN LATER FCSTS SINCE LOWEST PRECIPITABLE WATER LINGERS
LONGEST OVER THE E.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 602 AM EDT TUE JUN 12 2012
WED MORNING WILL START WITH A SFC HIGH OVER THE CWA AND ZONAL FLOW
ALOFT. AS THE SFC HIGH CENTER MOVES TO LAKE HURON BY 00Z THU...SLY
FLOW WILL BE INCREASING THROUGH THE DAY SUNDAY. 850MB TEMPS WILL
INCREASE FROM A CWA AVG OF 4C 12Z WED TO 9C 00Z THU. WE SHOULD BE
ABLE TO MIX TO AROUND 800MB WED AFTERNOON...RESULTING IN HIGH TEMPS
IN THE MID 60S TO MID 70S AND MIN RH VALUES OF 20 TO 30 PERCENT
INTERIOR W...AND 25 TO 35 PERCENT INTERIOR E. THANKFULLY...WINDS
SHOULD BE LESS THAN 15MPH WITH GUSTS OF 20MPH OR LESS.
A SHORTWAVE TROUGH WILL MOVE E OVER LAKE WINNIPEG BY 00Z FRI...WITH
A SFC LOW BENEATH IT AND A SFC TROUGH STRETCHING INTO WRN MN. WHILE
THE SFC HIGH WILL HAVE MOVED WELL INTO QUEBEC...A SFC RIDGE WILL
REMAIN OVER THE LOWER GREAT LAKES...INCREASING THE PRESSURE GRADIENT
/AND THUS THE SLY FLOW/ OVER THE CWA. BY 00Z THU...850MB TEMPS WILL
INCREASE TO AROUND 15C...MAKING FOR HIGH TEMPS IN THE 70S TO LOW 80S
OVER MOST OF UPPER MI. WITH THE INCREASED SLY FLOW...MID LEVEL
MOISTURE WILL BE GREATER THAN ON WED...BUT MODELS SHOW A VERY DRY
LAYER AROUND 875MB...SO RH VALUES MAY FALL TO AROUND 30 PERCENT
INLAND ON THU. SOME MODELS DO TRY TO BRING IN SOME PRECIP OVER FAR
WRN UPPER MI AND WRN LAKE SUPERIOR...BUT MAJORITY OF GUIDANCE KEEPS
THE PRECIP JUST W OF THE CWA. WILL GO WITH THE DRIER IDEA GIVEN VERY
DRY LOW LEVELS AND DRY TREND AS OF LATE. GENERALLY...SFC WINDS
SHOULD BE AROUND 15MPH WITH GUSTS OF 20-25MPH THU AFTERNOON/EVENING.
THE WINNIPEG SHORTWAVE MOVES TO HUDSON BAY BY 18Z FRI...BUT THE SFC
TROUGH SHOULD STAY NW OF THE CWA THROUGH FRI. MODELS ARE IN FAIRLY
GOOD GENERAL AGREEMENT SHOWING SOME PRECIP ACROSS THE CWA FRI AS
STRONG SLY FLOW CONTINUES. WE SHOULD SEE BETTER MOISTURE...SO SOME
PRECIP IS POSSIBLE...BUT WE WILL BE LACKING A GOOD FORCING MECHANISM
SO WILL NOT GO HIGHER THAN LOW CHANCE POPS. 850MB TEMPS INCREASE A
DEGREE OR TWO FROM THU...RESULTING IN HIGH TEMPS FROM THE MID 70S TO
MID 80S...WARMEST INTERIOR W.
MODEL AGREEMENT INCREASES CONSIDERABLY FOR SAT THROUGH MON WITH THE
PASSAGE OF A SERIES OF SHORTWAVES...DECREASING FORECAST CONFIDENCE
SIGNIFICANTLY. MODELS ARE IN GENERAL AGREEMENT IN SHOWING A DEEP
UPPER TROUGH MOVING INTO THE NRN PLAINS STATES MON...BUT HOW DEEP
AND HOW FAR E THE TROUGH IS REMAINS IN QUESTION...AND THESE ASPECTS
OF THIS SYSTEM WILL PLAY A CRUCIAL ROLE FOR THE FORECAST FOR MON.
USED A CONSENSUS OF MODELS FOR THIS TIME FRAME.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 124 PM EDT TUE JUN 12 2012
ALTHOUGH SOME LOWER CLDS/MVFR CIGS MAY LINGER EARLY AT SAW...THE
ARRIVAL OF HI PRES/DRIER AIR WL BRING VFR CONDITIONS THE REST OF
THIS FCST PERIOD. GUSTY NW WINDS THIS AFTN WL ALSO DIMINISH BY TNGT
WITH THE WEAKER PRES GRADIENT/LOSS OF DAYTIME HEATING. EXPECT A
STRONGER SW FLOW TO DVLP ON WED ONCE THE HI CENTER SHIFTS TO THE E
OVER NRN LOWER MI.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 602 AM EDT TUE JUN 12 2012
STRONG PUSH OF COLDER AIR INTO THE UPPER LAKES WILL RESULT IN W TO
NW WINDS OF 20-30KT TODAY. THERE MAY BE A FEW GALE FORCE GUSTS ON
SOME OF THE HIGHEST OBSERVING PLATFORMS OVER THE E HALF OF THE LAKE
THRU THE MORNING HRS. HIGH PRES OVER THE NRN PLAINS WILL THEN ARRIVE
OVER THE WESTERN GREAT LAKES TONIGHT...RESULTING IN WINDS
DIMINISHING TO UNDER 20KT FROM W TO E LATE THIS AFTN THRU TONIGHT.
THE HIGH WILL SHIFT TO QUEBEC WED NIGHT...AND THEN FOR THE REMAINDER
OF THE WEEK...THE BASIC PATTERN WILL FEATURE A HIGH PRES RIDGE OVER
THE ERN CONUS WITH A LOW PRES TROF FROM THE WRN HIGH PLAINS TO
HUDSON BAY. A WAVE OF LOW PRES LIFTING TOWARD HUDSON BAY THU/FRI MAY
RESULT IN A PERIOD OF SOUTHERLY 15-25KT WINDS THU/THU NIGHT OVER
CNTRL LAKE SUPERIOR. OTHERWISE...WINDS WILL BE UNDER 20KT WED THRU
SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
FROST ADVISORY FROM MIDNIGHT TONIGHT TO 6 AM CDT WEDNESDAY FOR
MIZ009>011.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...KC
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS RALEIGH NC
256 PM EDT TUE JUN 12 2012
.SYNOPSIS...
A COLD FRONT WILL PUSH SLOWLY SOUTHEAST THROUGH THE REGION LATE
TONIGHT AND WEDNESDAY...BRINGING COOLER AND MUCH DRIER CONDITIONS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 230 PM TUESDAY...
OVERVIEW:
A WEAK MID-LEVEL TROUGH CENTERED OVER THE WESTERN CAROLINAS (NEAR
I-77 PER 700 MB 15Z SPC MESOANALYSIS) WILL TRACK SLOWLY EASTWARD
INTO THE CENTRAL CAROLINAS THIS AFTERNOON/EVENING...PROGRESSING TO
THE CAROLINA COAST BY 12Z WED MORNING. IN THE LOWER LEVELS...A
SFC-H85 REFLECTION ATTENDANT THE MID-LEVEL WAVE WILL ALSO PROGRESS
EASTWARD INTO THE CENTRAL CAROLINAS. FURTHER UPSTREAM...A COLD FRONT
EXTENDING SSW FROM THE GREAT LAKES INTO THE WESTERN OH/TN VALLEY AT
15Z THIS MORNING WILL PROGRESS INTO THE SOUTHERN APPALACHIANS BY 00Z
THIS EVENING. THE FRONT WILL SLOW DOWN AND BECOME INCREASINGLY
WEST-EAST ORIENTED TONIGHT...THEN PROGRESS SOUTH THROUGH THE AREA ON
WED AS HIGH PRESSURE STRENGTHENS OVER THE GREAT LAKES AND NORTHERN
MID-ATLANTIC.
PRECIPITATION CHANCES:
DESPITE A VERY MOIST BOUNDARY LAYER WITH SFC DEWPOINTS IN THE LOWER
70S...WEAK MID-LEVEL LAPSE RATES AND EXTENSIVE CLOUD COVER OVER THE
AREA SHOULD TEMPER DIURNAL DESTABILIZATION THIS AFTERNOON ALONG/EAST
OF HWY 1...WHERE 500-1000 J/KG OF MLCAPE IS PROGGED AT BEST. IN THE
WESTERN PIEDMONT...LESS CLOUD COVER AND BETTER INSOLATION WILL LEAD
TO STRONGER DIURNAL DESTABILIZATION...WITH MLCAPE VALUES PROGGED AT
1000-1500 J/KG. BASED ON SPC MESOANALYSIS AND THE LATEST
OBSERVATIONAL DATA...THE LOW/MID-LEVEL TROUGH IN VICINITY OF I-77
OVER THE WESTERN CAROLINAS AT 15Z WILL BE THE PRIMARY FOCUSING
MECHANISM FOR CONVECTION TODAY AS IT PROGRESSES EASTWARD INTO
CENTRAL NC IN THE PRESENCE OF A TROPICAL (PWAT NEAR 2.00") AIRMASS.
15Z VWP DATA FROM SURROUNDING SITES ALREADY SHOW WESTERLY LOW-LEVEL
FLOW AT GSP/RNK/CAE...SUGGESTING THE BEST LOW-LEVEL CONVERGENCE AND
FOCUS FOR CONVECTION TODAY SHOULD REMAIN ALONG AND EAST OF HIGHWAY
1...AND WILL MAINTAIN CATEGORICAL (80%) PRECIPITATION CHANCES IN
THAT AREA. FURTHER WEST THE FORECAST IS MORE UNCERTAIN. ALTHOUGH THE
BEST CONVERGENCE WITH THE LOW/MID-LEVEL TROUGH IS ALREADY IN
VICINITY OF HWY 1...15Z WV IMAGERY SHOWED A SHEAR AXIS PROGRESSING
EASTWARD THROUGH EASTERN KY/CENTRAL TN...AND THE LATEST RAP MODEL
DATA PROGS THIS FEATURE TO PROGRESS INTO THE MOUNTAINS AND FOOTHILLS
LATER THIS AFTERNOON AND EVENING (IN VICINITY OF PEAK HEATING).
ALTERNATELY...DIFFERENTIAL HEATING IN THE PRESENCE OF A VERY MOIST
AIRMASS MAY LEAD TO THE DEVELOPMENT OF ISOLD/SCT CONVECTION IN THE
MOUNTAINS EARLY THIS AFTERNOON...WHICH COULD PROGRESS EAST/SE INTO
THE WESTERN PIEDMONT BY MID TO LATE AFTERNOON VIA 15 KT W/NW
MID-LEVEL FLOW.
THE 00-12Z HIGH-RES CONVECTION ALLOWING MODELS OFFER VARYING
SOLUTIONS WITH REGARD TO CONVECTION THIS AFTERNOON... RANGING FROM
LITTLE MORE THAN ISOLD CONVECTION IN THE WESTERN PIEDMONT TO THE
DEVELOPMENT OF A SW-NE ORIENTED LINE OF CONVECTION FROM CLT-INT AT
20Z THAT PROGRESSES THROUGH ALL OF CENTRAL NC BY SUNSET.
ADDITIONALLY...LARGE MCS`S UPSTREAM OF THE AREA LAST NIGHT MAY HAVE
ALTERED THE MID-LEVELS IN A MANNER NOT CAPTURED WELL BY THE 00-06Z
MODEL RUNS...ADDING FURTHER UNCERTAINTY TO THE PRECIP FORECAST. WITH
THE ABOVE IN MIND...FEEL THAT IT WOULD BE UNWISE TO REDUCE PRECIP
CHANCES MUCH BELOW WHAT HAS BEEN PREVIOUSLY ADVERTISED IN THE
WESTERN PIEDMONT. AFTER SUNSET...EXPECT CONVECTION TO WEAKEN AND
SHIFT SOUTHEAST IN CONCERT WITH THE MID-LEVEL TROUGH...WITH PRECIP
CHANCES DECREASING AND ENDING FROM NW-SE BY OR SHORTLY AFTER
MIDNIGHT AS A DRIER MID-LEVEL AIRMASS PROGRESSES INTO THE AREA.
SEVERE/FLOODING THREAT:
DO NOT ANTICIPATE A THREAT FOR AREA-WIDE FLOODING GIVEN A LACK OF
WIDESPREAD HEAVY RAIN YESTERDAY (ISOLD AREAS GOT 1-2") AND 1-3 HR
FLASH FLOOD GUIDANCE IN THE 2-4" RANGE IN MOST LOCATIONS (EXCLUDING
URBAN AREAS). HOWEVER...GIVEN THE TROPICAL AIRMASS IN PLACE...
RAINFALL RATES WITH CONVECTION THIS AFTERNOON WILL BE ON THE
HIGH-END...AND A LOCALIZED THREAT FOR FLOODING WILL CERTAINLY BE
PRESENT...PRIMARILY IN URBAN AREAS. ALTHOUGH MODERATE INSTABILITY
WILL BE POSSIBLE IN THE WESTERN PIEDMONT THIS AFT/EVE...DEEP LAYER
SHEAR IS PROGGED TO BE NO HIGHER THAN 15-20 KT...AND ORGANIZED
CONVECTION IS NOT EXPECTED. RELATIVELY BETTER INSOLATION IN THE
WESTERN PIEDMONT MAY YIELD 500-750 J/KG OF DCAPE THIS AFTERNOON...IN
THE PRESENCE OF 1.50"+ PWAT VALUES. THIS COMBINATION OF PRECIP
LOADING AND BOUNDARY LAYER EVAP COOLING COULD RESULT IN ISOLD SEVERE
DOWNBURSTS IN THE WESTERN PIEDMONT BETWEEN 300-800 PM.
TEMPERATURES:
EXTENSIVE CLOUD COVER AND SHOWER ACTIVITY WILL KEEP HIGHS TODAY
SIMILAR TO YESTERDAY...IN THE LOWER 80S...OR 81-85F. LOWS TONIGHT
WILL PRIMARILY DEPEND ON THE PROGRESS OF THE COLD (DRY) FRONT
APPROACHING THE AREA FROM THE NORTHWEST. THE BULK OF MODEL GUIDANCE
AGREES THAT THE FRONT SHOULD MAKE PROGRESS INTO THE N/NW PIEDMONT BY
SUNRISE WED...AND WILL INDICATE LOWS RANGING FROM THE MID/UPPER 60S
N/NW TO ~70F SOUTHEAST. -VINCENT
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
AS OF 245 PM TUESDAY...
WEDNESDAY:
THE MID-LEVEL TROUGH TRACKING EASTWARD INTO CENTRAL NC TODAY IS
PROGGED TO PROGRESS TO THE CAROLINA COAST BY 12Z WED...WITH A MUCH
DRIER MID-LEVEL AIRMASS OVERSPREADING THE AREA. IN THE LOWER
LEVELS...THE SW-NE ORIENTED COLD FRONT LOCATED OVER THE CENTRAL
OH/TN VALLEY THIS AFTERNOON WILL BECOME MORE WEST-EAST ORIENTED AS
IT MOVES INTO THE MID-ATLANTIC TONIGHT. THE FRONT WILL PROGRESS
SOUTHWARD THROUGH CENTRAL NC DURING THE DAY WED AS HIGH PRESSURE
STRENGTHENS OVER THE GREAT LAKES. THE LATEST MODEL GUIDANCE SHOWS
THE LEADING EDGE OF THE FRONT (AND WIND SHIFT TO THE N/NE) OCCURRING
AROUND OR SHORTLY AFTER SUNRISE WED MORNING...HOWEVER...MODEL
GUIDANCE IS IN RELATIVELY GOOD AGREEMENT THAT THE BOUNDARY LAYER
WILL REMAIN RELATIVELY MOIST THROUGH PEAK HEATING WED...WITH THE
BULK OF THE DRIER AIR NOT ADVECTING INTO CENTRAL NC FROM THE
NORTH/NE UNTIL THE LATE AFTERNOON/EVENING. FCST SOUNDINGS SHOW SFC
DEWPOINTS IN THE MID 60S ALMOST EVERYWHERE...WITH UPPER 60S TO NEAR
70F IN SOUTH/SW PORTIONS OF THE AREA. GIVEN THE RESIDUAL MOIST
BOUNDARY LAYER AND GOOD INSOLATION ASSOC/W DRIER MID-LEVELS...MLCAPE
VALUES COULD REACH AS HIGH AS 1000-1500 J/KG DURING PEAK HEATING...
PRIMARILY IN THE SANDHILLS/SW PIEDMONT. THOUGH THE BEST LOW-LEVEL
CONVERGENCE SHOULD BE ALONG OR JUST OFFSHORE THE CAROLINA COAST WED
AFTERNOON...MODEL GUIDANCE INDICATES SHORTWAVE ENERGY PROGRESSING
INTO WESTERN PORTIONS OF THE STATE BY MID/LATE AFTERNOON. IT IS
POSSIBLE THAT ISOLD CONVECTION COULD DEVELOP OVER PORTIONS OF THE
AREA BETWEEN 21-00Z IF SHORTWAVE ENERGY ARRIVES DURING PEAK HEATING
AND/OR PRIOR TO THE ADVECTION OF THE DRIER /MORE STABLE/ LOW-LEVEL
AIRMASS FROM THE NORTH. AT THIS TIME THE SHORTWAVE ENERGY APPEARS TO
ARRIVE A BIT TOO LATE...AND CONSIDERABLE DRY AIR ALOFT WOULD LIKELY
ACT TO HINDER EVEN ISOLD DEVELOPMENT. WILL KEEP PRECIP CHANCES
CONFINED TO A SLIGHT CHANCE SOUTH OF HWY 64 IN THE SANDHILLS/SW
PIEDMONT DURING THE AFTERNOON. WITH MOSTLY SUNNY SKIES AND COLD
ADVECTION OCCURRING CLOSER TOWARD SUNSET EXPECT HIGHS IN THE
MID/UPPER 80S. -VINCENT
WEDNESDAY NIGHT THROUGH FRIDAY:
MUCH DRIER AND COOLER CONDITIONS ARRIVE WEDNESDAY NIGHT AND
THURSDAY...LASTING THROUGH THE WEEKEND. THE MODELS ARE IN GOOD
GENERAL AGREEMENT IN THE DEVELOPMENT OF A WESTERN ATLANTIC UPPER
TROUGH WITH OUR REGION ON THE SUBSIDENCE SIDE OF THE TROUGH
WEDNESDAY NIGHT THROUGH THE END OF THE WEEK. THE MUCH DRIER AIR WILL
BE FELT WEDNESDAY NIGHT AND THURSDAY AS DEW POINTS FALL INTO THE 50S
WITH THE NNE LOW LEVEL FLOW. THE SKIES ARE EXPECTED TO BE MOSTLY
CLEAR WEDNESDAY NIGHT. SOME MIXING WILL CONTINUE WEDNESDAY NIGHT AS
THE HIGH PRESSURE BUILDS SOUTHWARD DOWN THE EASTERN SEABOARD INTO
NC/SC. LOWS MAY BE HELD UP AS WELL BY THE NE FLOW AT 5-10 MPH. WE
WILL LEAN TOWARD THE WARMER NAM GUIDANCE...60-65 FOR LOWS.
THURSDAY...MODELS ALSO SUGGEST A PERIOD OF CLOUDINESS WILL BE LIKELY
AS THE NE FLOW ADVECTS ATLANTIC MOISTURE ACROSS EASTERN VA INTO
CENTRAL NC DURING THE AFTERNOON AND EVENING. THE FORECAST SOUNDINGS
INDICATE PARTLY SUNNY TO MOSTLY CLOUDY SKIES THROUGH THE AFTERNOON
WITH HIGHS 75-82 (NE TO S). AS THE SURFACE HIGH PRESSURE STRENGTHENS
AND MOVES TOWARD THE MID-ATLANTIC STATES THURSDAY INTO THURSDAY
NIGHT...THE SKIES ARE EXPECTED TO BECOME MOSTLY CLEAR/MOSTLY SUNNY.
LOWS WILL DIP INTO THE 55-62 RANGE THURSDAY MORNING...WITH HIGHS
EXPECTED TO HOLD IN THE UPPER 70S TO LOWER 80S. THESE READINGS WILL
BE 5-8 DEGREES BELOW THE MID JUNE NORMALS. -BADGETT
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 220 PM TUESDAY...
AN EXTENDED DRY AND COOL PATTERN FOR MID JUNE.
THE SURFACE RIDGE ALONG THE EAST COAST IS FORECAST TO STRENGTHEN
FRIDAY INTO THE WEEKEND WITH A CONTINUED SUPPLY OF COOL AND DRY AIR
ADVECTION INTO NC. FRI-SUN SHOULD FEATURE MOSTLY CLEAR NIGHTS AND
MOSTLY SUNNY DAYS WITH LOW HUMIDITY. LOWS WILL BE IN THE 50S TO
AROUND 60 (5-10 DEGREES BELOW NORMAL). HIGHS WILL BE IN THE 77-82
RANGE... OR 5-8 DEGREES BELOW NORMAL).
BY MONDAY AND TUESDAY... THERE IS A CHANCE OF SOME RETROGRESSION OF
THE UPPER PATTERN WITH THE MID/UPPER LOW OVER THE WESTERN ATLANTIC
POSSIBLY DRIFTING SLOWLY WESTWARD TOWARD THE EASTERN SEABOARD.
STRONG RIDING IS EXPECTED TO OUR NW OVER THE OHIO VALLEY AND
MIDWEST. THIS WILL LEAD TO A CONTINUED NORTHERLY FLOW ALOFT WITH DRY
CONDITIONS. TEMPERATURES AND HUMIDITIES WILL MODERATE BACK CLOSER TO
MID JUNE NORMALS... YET NOT QUITE ALL THE WAY BACK. LOWS 62-67 WITH
HIGHS IN THE MID TO UPPER 80S.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 150 PM TUESDAY...
24-HR TAF PERIOD:
DIURNAL HEATING/MIXING HAS ALLOWED CEILINGS TO IMPROVE TO MVFR AT
ALL TAF SITES...WITH THE 17Z INT TERMINAL REPORTING VFR CEILINGS.
EXPECT CEILINGS TO GENERALLY RANGE FROM 2000-3500 FT THIS AFTERNOON
GIVEN THE VERY MOIST AIRMASS IN PLACE...WITH MVFR/IFR CONDITIONS
POSSIBLE BETWEEN 18-00Z AT ANY TAF SITE IN ASSOCIATION WITH
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS. GIVEN RELATIVELY
HIGH CHANCES FOR PRECIPITATION...WILL INCLUDE A TEMPO GROUP FOR
SHOWERS AND LOW-END MVFR CONDITIONS AT ALL TAF SITES DURING PEAK
HEATING. WIND GUSTS UP TO 25-35 KT WILL BE POSSIBLE IN ASSOCIATION
WITH ANY THUNDERSTORMS THIS AFTERNOON. THOUGH THE PROBABILITY IS
LOW...ISOLATED CONVECTIVE WIND GUSTS AS HIGH AS 35-50 KT CANNOT BE
RULED OUT AT THE INT/GSO TAF SITES BETWEEN 19-23Z. AFTER SUNSET...
IFR CONDITIONS ASSOCIATED WITH FOG OR LOW CEILINGS WILL BE POSSIBLE
AT ALL TAF SITES GIVEN A VERY MOIST BOUNDARY LAYER...LIGHT/VARIABLE
OR CALM WINDS AND SOME EROSION OF CLOUD COVER AS THE MID-LEVELS
BEGIN TO DRY OUT FROM THE WEST. A COLD (DRY) FRONT WILL APPROACH THE
AREA FROM THE NORTHWEST AFTER MIDNIGHT AND PROGRESS INTO THE N/NW
PIEDMONT BY SUNRISE. IT IS POSSIBLE THAT ENOUGH DRY AIR MAY ADVECT
INTO THE INT/GSO TERMINALS TO IMPROVE CONDITIONS PRIOR TO SUNRISE...
THOUGH UNCERTAINTY REMAINS HIGH. FURTHER SOUTH AND EAST AT THE
RDU/RWI/FAY TERMINALS...MVFR OR IFR CONDITIONS ARE LIKELY TO PREVAIL
THROUGH 12Z WED MORNING. ASIDE FROM LINGERING MVFR CEILINGS AT THE
FAY/RWI TERMINALS WED MORNING...EXPECT VFR CONDITIONS BY THE END OF
THE TAF PERIOD AS A DRIER AIRMASS PROGRESSES INTO THE AREA IN THE
WAKE OF THE FRONT. LIGHT WEST/NW WINDS WILL BECOME NORTHEAST AT
10-15 KT IN THE WAKE OF THE FRONT...PRIMARILY AFTER 12Z WED.
18Z WEDNESDAY THROUGH SUNDAY:
VFR CONDITIONS ARE GENERALLY EXPECTED BEHIND THE FRONT WEDNESDAY
AFTERNOON/NIGHT AS A DRIER AIRMASS SETTLES INTO CENTRAL NC.
HOWEVER...NORTHEAST FLOW OFF THE ATLANTIC MAY LEAD TO MVFR CEILINGS
ACROSS THE AREA (PRIMARILY RDU/RWI/FAY TERMINALS) ON THURSDAY...
THOUGH UNCERTAINTY REMAINS HIGH. NORTHEAST LOW-LEVEL FLOW WILL
PERSIST INTO THE WEEKEND IN ASSOCIATION WITH UNSEASONABLY STRONG
HIGH PRESSURE EXTENDING SOUTHWEST FROM NEW ENGLAND INTO THE
MID-ATLANTIC/CAROLINAS. ALTHOUGH CHANCES FOR PRECIPITATION APPEAR
LOW AT THIS TIME...EXPECT A POTENTIAL FOR MVFR CEILINGS FRIDAY
THROUGH THE WEEKEND GIVEN NE/NNE LOW-LEVEL FLOW. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BADGETT
NEAR TERM...VINCENT
SHORT TERM...VINCENT/BADGETT
LONG TERM...BADGETT
AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS RALEIGH NC
220 PM EDT TUE JUN 12 2012
.SYNOPSIS...
A COLD FRONT WILL PUSH SLOWLY SOUTHEAST THROUGH THE REGION LATE
TONIGHT AND WEDNESDAY... BRINGING COOLER AND MUCH DRIER CONDITIONS.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
AS OF 1230 PM TUESDAY...
OVERVIEW:
A WEAK MID-LEVEL TROUGH CENTERED OVER THE WESTERN CAROLINAS (NEAR
I-77 PER 700 MB 15Z SPC MESOANALYSIS) WILL TRACK SLOWLY EASTWARD
INTO THE CENTRAL CAROLINAS THIS AFTERNOON/EVENING...PROGRESSING TO
THE CAROLINA COAST BY 12Z WED MORNING. IN THE LOWER LEVELS...A
SFC-H85 REFLECTION ATTENDANT THE MID-LEVEL WAVE WILL ALSO PROGRESS
EASTWARD INTO THE CENTRAL CAROLINAS. FURTHER UPSTREAM...A COLD FRONT
EXTENDING SSW FROM THE GREAT LAKES INTO THE WESTERN OH/TN VALLEY AT
15Z THIS MORNING WILL PROGRESS INTO THE SOUTHERN APPALACHIANS BY 00Z
THIS EVENING. THE FRONT WILL SLOW DOWN AND BECOME INCREASINGLY
WEST-EAST ORIENTED TONIGHT...THEN PROGRESS SOUTH THROUGH THE AREA ON
WED AS HIGH PRESSURE STRENGTHENS OVER THE GREAT LAKES AND NORTHERN
MID-ATLANTIC.
PRECIPITATION CHANCES:
DESPITE A VERY MOIST BOUNDARY LAYER WITH SFC DEWPOINTS IN THE LOWER
70S...WEAK MID-LEVEL LAPSE RATES AND EXTENSIVE CLOUD COVER OVER THE
AREA SHOULD TEMPER DIURNAL DESTABILIZATION THIS AFTERNOON ALONG/EAST
OF HWY 1...WHERE 500-1000 J/KG OF MLCAPE IS PROGGED AT BEST. IN THE
WESTERN PIEDMONT...LESS CLOUD COVER AND BETTER INSOLATION WILL LEAD
TO STRONGER DIURNAL DESTABILIZATION...WITH MLCAPE VALUES PROGGED AT
1000-1500 J/KG. BASED ON SPC MESOANALYSIS AND THE LATEST
OBSERVATIONAL DATA...THE LOW/MID-LEVEL TROUGH IN VICINITY OF I-77
OVER THE WESTERN CAROLINAS AT 15Z WILL BE THE PRIMARY FOCUSING
MECHANISM FOR CONVECTION TODAY AS IT PROGRESSES EASTWARD INTO
CENTRAL NC IN THE PRESENCE OF A TROPICAL (PWAT NEAR 2.00") AIRMASS.
15Z VWP DATA FROM SURROUNDING SITES ALREADY SHOW WESTERLY LOW-LEVEL
FLOW AT GSP/RNK/CAE...SUGGESTING THE BEST LOW-LEVEL CONVERGENCE AND
FOCUS FOR CONVECTION TODAY SHOULD REMAIN ALONG AND EAST OF HIGHWAY
1...AND WILL MAINTAIN CATEGORICAL (80%) PRECIPITATION CHANCES IN
THAT AREA. FURTHER WEST THE FORECAST IS MORE UNCERTAIN. ALTHOUGH THE
BEST CONVERGENCE WITH THE LOW/MID-LEVEL TROUGH IS ALREADY IN
VICINITY OF HWY 1...15Z WV IMAGERY SHOWED A SHEAR AXIS PROGRESSING
EASTWARD THROUGH EASTERN KY/CENTRAL TN...AND THE LATEST RAP MODEL
DATA PROGS THIS FEATURE TO PROGRESS INTO THE MOUNTAINS AND FOOTHILLS
LATER THIS AFTERNOON AND EVENING (IN VICINITY OF PEAK HEATING).
ALTERNATELY...DIFFERENTIAL HEATING IN THE PRESENCE OF A VERY MOIST
AIRMASS MAY LEAD TO THE DEVELOPMENT OF ISOLD/SCT CONVECTION IN THE
MOUNTAINS EARLY THIS AFTERNOON...WHICH COULD PROGRESS EAST/SE INTO
THE WESTERN PIEDMONT BY MID TO LATE AFTERNOON VIA 15 KT W/NW
MID-LEVEL FLOW.
THE 00Z AND 06Z HIGH-RES CONVECTION ALLOWING MODELS OFFER VARYING
SOLUTIONS WITH REGARD TO CONVECTION THIS AFTERNOON... RANGING FROM
LITTLE MORE THAN ISOLD CONVECTION IN THE WESTERN PIEDMONT TO THE
DEVELOPMENT OF A SW-NE ORIENTED LINE OF CONVECTION FROM CLT-INT AT
20Z THAT PROGRESSES THROUGH ALL OF CENTRAL NC BY SUNSET.
ADDITIONALLY...LARGE MCS`S UPSTREAM OF THE AREA LAST NIGHT MAY HAVE
ALTERED THE MID-LEVELS IN A MANNER NOT CAPTURED WELL BY THE 00-06Z
MODEL RUNS...ADDING FURTHER UNCERTAINTY TO THE PRECIP FORECAST. WITH
THE ABOVE IN MIND...FEEL THAT IT WOULD BE UNWISE TO REDUCE PRECIP
CHANCES MUCH BELOW WHAT HAS BEEN PREVIOUSLY ADVERTISED IN THE
WESTERN PIEDMONT. AFTER SUNSET...EXPECT CONVECTION TO WEAKEN AND
SHIFT SOUTHEAST IN CONCERT WITH THE MID-LEVEL TROUGH...WITH PRECIP
CHANCES DECREASING AND ENDING FROM NW-SE BY OR SHORTLY AFTER
MIDNIGHT AS A DRIER MID-LEVEL AIRMASS PROGRESSES INTO THE AREA.
SEVERE/FLOODING THREAT:
DO NOT ANTICIPATE A THREAT FOR AREA-WIDE FLOODING GIVEN A LACK OF
WIDESPREAD HEAVY RAIN YESTERDAY (ISOLD AREAS GOT 1-2") AND 1-3 HR
FLASH FLOOD GUIDANCE IN THE 2-4" RANGE IN MOST LOCATIONS (EXCLUDING
URBAN AREAS). HOWEVER...GIVEN THE TROPICAL AIRMASS IN PLACE...
RAINFALL RATES WITH CONVECTION THIS AFTERNOON WILL BE ON THE
HIGH-END...AND A LOCALIZED THREAT FOR FLOODING WILL CERTAINLY BE
PRESENT...PRIMARILY IN URBAN AREAS. ALTHOUGH MODERATE INSTABILITY
WILL BE POSSIBLE IN THE WESTERN PIEDMONT THIS AFT/EVE...DEEP LAYER
SHEAR IS PROGGED TO BE NO HIGHER THAN 15-20 KT...AND ORGANIZED
CONVECTION IS NOT EXPECTED. RELATIVELY BETTER INSOLATION IN THE
WESTERN PIEDMONT MAY YIELD 500-750 J/KG OF DCAPE THIS AFTERNOON...IN
THE PRESENCE OF 1.50"+ PWAT VALUES. THIS COMBINATION OF PRECIP
LOADING AND BOUNDARY LAYER EVAP COOLING COULD RESULT IN ISOLD SEVERE
DOWNBURSTS IN THE WESTERN PIEDMONT BETWEEN 300-800 PM.
TEMPERATURES:
EXTENSIVE CLOUD COVER AND SHOWER ACTIVITY WILL KEEP HIGHS TODAY
SIMILAR TO YESTERDAY...IN THE LOWER 80S...OR 81-85F. LOWS TONIGHT
WILL PRIMARILY DEPEND ON THE PROGRESS OF THE COLD (DRY) FRONT
APPROACHING THE AREA FROM THE NORTHWEST. THE BULK OF MODEL GUIDANCE
AGREES THAT THE FRONT SHOULD MAKE PROGRESS INTO THE N/NW PIEDMONT BY
SUNRISE WED...AND WILL INDICATE LOWS RANGING FROM THE MID/UPPER 60S
N/NW TO ~70F SOUTHEAST. -VINCENT
FOR WEDNESDAY:
THE SURFACE TROUGH IS EXPECTED TO HAVE SHIFTED TO THE COASTAL
CAROLINAS BY WEDNESDAY MORNING WITH MAINLY NORTHERLY FLOW AT 850 MB.
THE MAIN COOL FRONT SHOULD EASE SLOWLY TO THE SSE INTO THE NORTHERN
CWA DURING THE AFTERNOON AS A PORTION OF THE WEAKENING NORTHERN
STREAM MID LEVEL SHORTWAVE DROPS SE TOWARD NC. PW VALUES ARE
EXPECTED TO DROP BACK DOWN TO NEAR NORMAL VALUES AS DRIER AIR
ADVECTS IN FROM THE NNW... MOST MARKEDLY IN THE MID-UPPER LEVELS...
ALTHOUGH ELEVATED PW NEAR 1.5 INCHES WILL LIKELY REMAIN OVER THE
SOUTHEAST CWA. AS A 60-70 KT SWRLY UPPER JET SHIFTS OVER THE
DELMARVA AND NJ... WEAK UPPER DIVERGENCE WEDNESDAY AFTERNOON OVER SE
NC WORKING ON THE LINGERING MOISTURE AND STEEPENING WET BULB LAPSE
RATE MAY LEAD TO SCATTERED SHOWERS AND STORMS HERE... SO WILL LEAVE
IN CHANCE POPS IN THE AFTERNOON WITH DRY CONDITIONS ELSEWHERE WHERE
LOW LEVEL FLOW WILL BECOME NORTH-NORTHEASTERLY. AN ANTICIPATED LOW
LEVEL DRY ADIABATIC LAPSE RATE SUGGESTS WARM HIGHS OF 84-88... WITH
SCATTERED TO BROKEN CONVECTIVE CLOUDS AREAWIDE... MOST NUMEROUS
ACROSS THE EAST AND SOUTH. -GIH
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
AS OF 200 PM TUESDAY...
MUCH DRIER AND COOLER CONDITIONS ARRIVE WEDNESDAY NIGHT AND
THURSDAY... LASTING THROUGH THE WEEKEND.
THE MODELS ARE IN GOOD GENERAL AGREEMENT IN THE DEVELOPMENT OF A
WESTERN ATLANTIC UPPER TROUGH WITH OUR REGION ON THE SUBSIDENCE SIDE
OF THE TROUGH WEDNESDAY NIGHT THROUGH THE END OF THE WEEK. THE MUCH
DRIER AIR WILL BE FELT WEDNESDAY NIGHT AND THURSDAY AS DEW POINTS
FALL INTO THE 50S WITH THE NNE LOW LEVEL FLOW. THE SKIES ARE
EXPECTED TO BE MOSTLY CLEAR WEDNESDAY NIGHT. SOME MIXING WILL
CONTINUE WEDNESDAY NIGHT AS THE HIGH PRESSURE BUILDS SOUTHWARD DOWN
THE EASTERN SEABOARD INTO NC/SC. LOWS MAY BE HELD UP AS WELL BY THE
NE FLOW AT 5-10 MPH. WE WILL LEAN TOWARD THE WARMER NAM GUIDANCE...
60-65 FOR LOWS. THURSDAY... MODELS ALSO SUGGEST A PERIOD OF
CLOUDINESS WILL BE LIKELY AS THE NE FLOW ADVECTS ATLANTIC MOISTURE
ACROSS EASTERN VA INTO CENTRAL NC DURING THE AFTERNOON AND EVENING.
THE FORECAST SOUNDINGS INDICATE PARTLY SUNNY TO MOSTLY CLOUDY SKIES
THROUGH THE AFTERNOON WITH HIGHS 75-82 (NE TO S). AS THE SURFACE
HIGH PRESSURE STRENGTHENS AND MOVES TOWARD THE MID-ATLANTIC STATES
THURSDAY INTO THURSDAY NIGHT... THE SKIES ARE EXPECTED TO BECOME
MOSTLY CLEAR/MOSTLY SUNNY. LOWS WILL DIP INTO THE 55-62 RANGE
THURSDAY MORNING... WITH HIGHS EXPECTED TO HOLD IN THE UPPER 70S TO
LOWER 80S. THESE READINGS WILL BE 5-8 DEGREES BELOW THE MID JUNE
NORMALS.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 220 PM TUESDAY...
AN EXTENDED DRY AND COOL PATTERN FOR MID JUNE.
THE SURFACE RIDGE ALONG THE EAST COAST IS FORECAST TO STRENGTHEN
FRIDAY INTO THE WEEKEND WITH A CONTINUED SUPPLY OF COOL AND DRY AIR
ADVECTION INTO NC. FRI-SUN SHOULD FEATURE MOSTLY CLEAR NIGHTS AND
MOSTLY SUNNY DAYS WITH LOW HUMIDITY. LOWS WILL BE IN THE 50S TO
AROUND 60 (5-10 DEGREES BELOW NORMAL). HIGHS WILL BE IN THE 77-82
RANGE... OR 5-8 DEGREES BELOW NORMAL).
BY MONDAY AND TUESDAY... THERE IS A CHANCE OF SOME RETROGRESSION OF
THE UPPER PATTERN WITH THE MID/UPPER LOW OVER THE WESTERN ATLANTIC
POSSIBLY DRIFTING SLOWLY WESTWARD TOWARD THE EASTERN SEABOARD.
STRONG RIDING IS EXPECTED TO OUR NW OVER THE OHIO VALLEY AND
MIDWEST. THIS WILL LEAD TO A CONTINUED NORTHERLY FLOW ALOFT WITH DRY
CONDITIONS. TEMPERATURES AND HUMIDITIES WILL MODERATE BACK CLOSER TO
MID JUNE NORMALS... YET NOT QUITE ALL THE WAY BACK. LOWS 62-67 WITH
HIGHS IN THE MID TO UPPER 80S.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 150 PM TUESDAY...
24-HR TAF PERIOD:
DIURNAL HEATING/MIXING HAS ALLOWED CEILINGS TO IMPROVE TO MVFR AT
ALL TAF SITES...WITH THE 17Z INT TERMINAL REPORTING VFR CEILINGS.
EXPECT CEILINGS TO GENERALLY RANGE FROM 2000-3500 FT THIS AFTERNOON
GIVEN THE VERY MOIST AIRMASS IN PLACE...WITH MVFR/IFR CONDITIONS
POSSIBLE BETWEEN 18-00Z AT ANY TAF SITE IN ASSOCIATION WITH
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS. GIVEN RELATIVELY
HIGH CHANCES FOR PRECIPITATION...WILL INCLUDE A TEMPO GROUP FOR
SHOWERS AND LOW-END MVFR CONDITIONS AT ALL TAF SITES DURING PEAK
HEATING. WIND GUSTS UP TO 25-35 KT WILL BE POSSIBLE IN ASSOCIATION
WITH ANY THUNDERSTORMS THIS AFTERNOON. THOUGH THE PROBABILITY IS
LOW...ISOLATED CONVECTIVE WIND GUSTS AS HIGH AS 35-50 KT CANNOT BE
RULED OUT AT THE INT/GSO TAF SITES BETWEEN 19-23Z. AFTER SUNSET...
IFR CONDITIONS ASSOCIATED WITH FOG OR LOW CEILINGS WILL BE POSSIBLE
AT ALL TAF SITES GIVEN A VERY MOIST BOUNDARY LAYER...LIGHT/VARIABLE
OR CALM WINDS AND SOME EROSION OF CLOUD COVER AS THE MID-LEVELS
BEGIN TO DRY OUT FROM THE WEST. A COLD (DRY) FRONT WILL APPROACH THE
AREA FROM THE NORTHWEST AFTER MIDNIGHT AND PROGRESS INTO THE N/NW
PIEDMONT BY SUNRISE. IT IS POSSIBLE THAT ENOUGH DRY AIR MAY ADVECT
INTO THE INT/GSO TERMINALS TO IMPROVE CONDITIONS PRIOR TO SUNRISE...
THOUGH UNCERTAINTY REMAINS HIGH. FURTHER SOUTH AND EAST AT THE
RDU/RWI/FAY TERMINALS...MVFR OR IFR CONDITIONS ARE LIKELY TO PREVAIL
THROUGH 12Z WED MORNING. ASIDE FROM LINGERING MVFR CEILINGS AT THE
FAY/RWI TERMINALS WED MORNING...EXPECT VFR CONDITIONS BY THE END OF
THE TAF PERIOD AS A DRIER AIRMASS PROGRESSES INTO THE AREA IN THE
WAKE OF THE FRONT. LIGHT WEST/NW WINDS WILL BECOME NORTHEAST AT
10-15 KT IN THE WAKE OF THE FRONT...PRIMARILY AFTER 12Z WED.
18Z WEDNESDAY THROUGH SUNDAY:
VFR CONDITIONS ARE GENERALLY EXPECTED BEHIND THE FRONT WEDNESDAY
AFTERNOON/NIGHT AS A DRIER AIRMASS SETTLES INTO CENTRAL NC.
HOWEVER...NORTHEAST FLOW OFF THE ATLANTIC MAY LEAD TO MVFR CEILINGS
ACROSS THE AREA (PRIMARILY RDU/RWI/FAY TERMINALS) ON THURSDAY...
THOUGH UNCERTAINTY REMAINS HIGH. NORTHEAST LOW-LEVEL FLOW WILL
PERSIST INTO THE WEEKEND IN ASSOCIATION WITH UNSEASONABLY STRONG
HIGH PRESSURE EXTENDING SOUTHWEST FROM NEW ENGLAND INTO THE
MID-ATLANTIC/CAROLINAS. ALTHOUGH CHANCES FOR PRECIPITATION APPEAR
LOW AT THIS TIME...EXPECT A POTENTIAL FOR MVFR CEILINGS FRIDAY
THROUGH THE WEEKEND GIVEN NE/NNE LOW-LEVEL FLOW. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BADGETT
NEAR TERM...VINCENT/HARTFIELD
SHORT TERM...BADGETT
LONG TERM...BADGETT
AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS RALEIGH NC
156 PM EDT TUE JUN 12 2012
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE NORTHWEST TONIGHT...THEN PUSH
SOUTH THROUGH THE AREA ON WEDNESDAY AS AN UPPER LEVEL DISTURBANCE
PROGRESSES OFFSHORE. DRIER CONDITIONS ARE EXPECTED WEDNESDAY
AFTERNOON THROUGH THE REMAINDER OF THE WORK WEEK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
AS OF 1230 PM TUESDAY...
OVERVIEW:
A WEAK MID-LEVEL TROUGH CENTERED OVER THE WESTERN CAROLINAS (NEAR
I-77 PER 700 MB 15Z SPC MESOANALYSIS) WILL TRACK SLOWLY EASTWARD
INTO THE CENTRAL CAROLINAS THIS AFTERNOON/EVENING...PROGRESSING TO
THE CAROLINA COAST BY 12Z WED MORNING. IN THE LOWER LEVELS...A
SFC-H85 REFLECTION ATTENDANT THE MID-LEVEL WAVE WILL ALSO PROGRESS
EASTWARD INTO THE CENTRAL CAROLINAS. FURTHER UPSTREAM...A COLD FRONT
EXTENDING SSW FROM THE GREAT LAKES INTO THE WESTERN OH/TN VALLEY AT
15Z THIS MORNING WILL PROGRESS INTO THE SOUTHERN APPALACHIANS BY 00Z
THIS EVENING. THE FRONT WILL SLOW DOWN AND BECOME INCREASINGLY
WEST-EAST ORIENTED TONIGHT...THEN PROGRESS SOUTH THROUGH THE AREA ON
WED AS HIGH PRESSURE STRENGTHENS OVER THE GREAT LAKES AND NORTHERN
MID-ATLANTIC.
PRECIPITATION CHANCES:
DESPITE A VERY MOIST BOUNDARY LAYER WITH SFC DEWPOINTS IN THE LOWER
70S...WEAK MID-LEVEL LAPSE RATES AND EXTENSIVE CLOUD COVER OVER THE
AREA SHOULD TEMPER DIURNAL DESTABILIZATION THIS AFTERNOON ALONG/EAST
OF HWY 1...WHERE 500-1000 J/KG OF MLCAPE IS PROGGED AT BEST. IN THE
WESTERN PIEDMONT...LESS CLOUD COVER AND BETTER INSOLATION WILL LEAD
TO STRONGER DIURNAL DESTABILIZATION...WITH MLCAPE VALUES PROGGED AT
1000-1500 J/KG. BASED ON SPC MESOANALYSIS AND THE LATEST
OBSERVATIONAL DATA...THE LOW/MID-LEVEL TROUGH IN VICINITY OF I-77
OVER THE WESTERN CAROLINAS AT 15Z WILL BE THE PRIMARY FOCUSING
MECHANISM FOR CONVECTION TODAY AS IT PROGRESSES EASTWARD INTO
CENTRAL NC IN THE PRESENCE OF A TROPICAL (PWAT NEAR 2.00") AIRMASS.
15Z VWP DATA FROM SURROUNDING SITES ALREADY SHOW WESTERLY LOW-LEVEL
FLOW AT GSP/RNK/CAE...SUGGESTING THE BEST LOW-LEVEL CONVERGENCE AND
FOCUS FOR CONVECTION TODAY SHOULD REMAIN ALONG AND EAST OF HIGHWAY
1...AND WILL MAINTAIN CATEGORICAL (80%) PRECIPITATION CHANCES IN
THAT AREA. FURTHER WEST THE FORECAST IS MORE UNCERTAIN. ALTHOUGH THE
BEST CONVERGENCE WITH THE LOW/MID-LEVEL TROUGH IS ALREADY IN
VICINITY OF HWY 1...15Z WV IMAGERY SHOWED A SHEAR AXIS PROGRESSING
EASTWARD THROUGH EASTERN KY/CENTRAL TN...AND THE LATEST RAP MODEL
DATA PROGS THIS FEATURE TO PROGRESS INTO THE MOUNTAINS AND FOOTHILLS
LATER THIS AFTERNOON AND EVENING (IN VICINITY OF PEAK HEATING).
ALTERNATELY...DIFFERENTIAL HEATING IN THE PRESENCE OF A VERY MOIST
AIRMASS MAY LEAD TO THE DEVELOPMENT OF ISOLD/SCT CONVECTION IN THE
MOUNTAINS EARLY THIS AFTERNOON...WHICH COULD PROGRESS EAST/SE INTO
THE WESTERN PIEDMONT BY MID TO LATE AFTERNOON VIA 15 KT W/NW
MID-LEVEL FLOW.
THE 00Z AND 06Z HIGH-RES CONVECTION ALLOWING MODELS OFFER VARYING
SOLUTIONS WITH REGARD TO CONVECTION THIS AFTERNOON... RANGING FROM
LITTLE MORE THAN ISOLD CONVECTION IN THE WESTERN PIEDMONT TO THE
DEVELOPMENT OF A SW-NE ORIENTED LINE OF CONVECTION FROM CLT-INT AT
20Z THAT PROGRESSES THROUGH ALL OF CENTRAL NC BY SUNSET.
ADDITIONALLY...LARGE MCS`S UPSTREAM OF THE AREA LAST NIGHT MAY HAVE
ALTERED THE MID-LEVELS IN A MANNER NOT CAPTURED WELL BY THE 00-06Z
MODEL RUNS...ADDING FURTHER UNCERTAINTY TO THE PRECIP FORECAST. WITH
THE ABOVE IN MIND...FEEL THAT IT WOULD BE UNWISE TO REDUCE PRECIP
CHANCES MUCH BELOW WHAT HAS BEEN PREVIOUSLY ADVERTISED IN THE
WESTERN PIEDMONT. AFTER SUNSET...EXPECT CONVECTION TO WEAKEN AND
SHIFT SOUTHEAST IN CONCERT WITH THE MID-LEVEL TROUGH...WITH PRECIP
CHANCES DECREASING AND ENDING FROM NW-SE BY OR SHORTLY AFTER
MIDNIGHT AS A DRIER MID-LEVEL AIRMASS PROGRESSES INTO THE AREA.
SEVERE/FLOODING THREAT:
DO NOT ANTICIPATE A THREAT FOR AREA-WIDE FLOODING GIVEN A LACK OF
WIDESPREAD HEAVY RAIN YESTERDAY (ISOLD AREAS GOT 1-2") AND 1-3 HR
FLASH FLOOD GUIDANCE IN THE 2-4" RANGE IN MOST LOCATIONS (EXCLUDING
URBAN AREAS). HOWEVER...GIVEN THE TROPICAL AIRMASS IN PLACE...
RAINFALL RATES WITH CONVECTION THIS AFTERNOON WILL BE ON THE
HIGH-END...AND A LOCALIZED THREAT FOR FLOODING WILL CERTAINLY BE
PRESENT...PRIMARILY IN URBAN AREAS. ALTHOUGH MODERATE INSTABILITY
WILL BE POSSIBLE IN THE WESTERN PIEDMONT THIS AFT/EVE...DEEP LAYER
SHEAR IS PROGGED TO BE NO HIGHER THAN 15-20 KT...AND ORGANIZED
CONVECTION IS NOT EXPECTED. RELATIVELY BETTER INSOLATION IN THE
WESTERN PIEDMONT MAY YIELD 500-750 J/KG OF DCAPE THIS AFTERNOON...IN
THE PRESENCE OF 1.50"+ PWAT VALUES. THIS COMBINATION OF PRECIP
LOADING AND BOUNDARY LAYER EVAP COOLING COULD RESULT IN ISOLD SEVERE
DOWNBURSTS IN THE WESTERN PIEDMONT BETWEEN 300-800 PM.
TEMPERATURES:
EXTENSIVE CLOUD COVER AND SHOWER ACTIVITY WILL KEEP HIGHS TODAY
SIMILAR TO YESTERDAY...IN THE LOWER 80S...OR 81-85F. LOWS TONIGHT
WILL PRIMARILY DEPEND ON THE PROGRESS OF THE COLD (DRY) FRONT
APPROACHING THE AREA FROM THE NORTHWEST. THE BULK OF MODEL GUIDANCE
AGREES THAT THE FRONT SHOULD MAKE PROGRESS INTO THE N/NW PIEDMONT BY
SUNRISE WED...AND WILL INDICATE LOWS RANGING FROM THE MID/UPPER 60S
N/NW TO ~70F SOUTHEAST. -VINCENT
FOR WEDNESDAY:
THE SURFACE TROUGH IS EXPECTED TO HAVE SHIFTED TO THE COASTAL
CAROLINAS BY WEDNESDAY MORNING WITH MAINLY NORTHERLY FLOW AT 850 MB.
THE MAIN COOL FRONT SHOULD EASE SLOWLY TO THE SSE INTO THE NORTHERN
CWA DURING THE AFTERNOON AS A PORTION OF THE WEAKENING NORTHERN
STREAM MID LEVEL SHORTWAVE DROPS SE TOWARD NC. PW VALUES ARE
EXPECTED TO DROP BACK DOWN TO NEAR NORMAL VALUES AS DRIER AIR
ADVECTS IN FROM THE NNW... MOST MARKEDLY IN THE MID-UPPER LEVELS...
ALTHOUGH ELEVATED PW NEAR 1.5 INCHES WILL LIKELY REMAIN OVER THE
SOUTHEAST CWA. AS A 60-70 KT SWRLY UPPER JET SHIFTS OVER THE
DELMARVA AND NJ... WEAK UPPER DIVERGENCE WEDNESDAY AFTERNOON OVER SE
NC WORKING ON THE LINGERING MOISTURE AND STEEPENING WET BULB LAPSE
RATE MAY LEAD TO SCATTERED SHOWERS AND STORMS HERE... SO WILL LEAVE
IN CHANCE POPS IN THE AFTERNOON WITH DRY CONDITIONS ELSEWHERE WHERE
LOW LEVEL FLOW WILL BECOME NORTH-NORTHEASTERLY. AN ANTICIPATED LOW
LEVEL DRY ADIABATIC LAPSE RATE SUGGESTS WARM HIGHS OF 84-88... WITH
SCATTERED TO BROKEN CONVECTIVE CLOUDS AREAWIDE... MOST NUMEROUS
ACROSS THE EAST AND SOUTH. -GIH
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
AS OF 255 AM TUESDAY...
A COLD FRONT...ATTENDANT TO A WEAK...SOUTHWARD DRIFTING SURFACE LOW
JUST OFFSHORE...WILL PUSH SOUTH THROUGH CENTRAL NC BY THURSDAY
MORNING. HIGH PRESSURE WILL SET UP OVER EASTERN CANADA AND EXTEND
SOUTH ALONG THE EAST COAST WHILE AN UPPER LEVEL RIDGE BUILDS FROM
THE DEEP SOUTH TO THE MIDWEST. FORECAST SOUNDINGS SHOW ENOUGH OF A
NORTHEASTERLY LOW LEVEL FETCH FOR SOME STRATUS THURSDAY
MORNING...ESPECIALLY OVER THE COASTAL PLAIN. DESPITE AN INITIAL
SURGE OF DRIER DEWPOINTS...WHICH ARE CURRENTLY IN THE UPEPR 40S OVER
THE NORTHERN PLAINS...GUIDANCE SHOWS A STRONG RECOVERY DURING THE
DAY WITH DEWPOINTS IN THE LOWER 60S. HOWEVER...MUCH DRIER MID LEVEL
AIR AND STRENGTHENING SUBSIDENCE SHOULD PRECLUDE ANY SHOWERS OR
STORMS. LOW LEVEL THICKNESSES ARE FORECAST TO FALL BELOW 1400M...TO
AS LOW AS 1385M BASED ON THE GFS...LEADING TO HIGHS IN THE LOW TO
MID 80S. PATCHY STRATUS COULD BE POSSIBLE AGAIN THURSDAY
NIGHT...THROUGH THE STRENGTHENING SURFACE RIDGE AXIS MAY HELP TO
KEEP STRATUS SUPPRESSED CLOSER TO THE COAST. LOWS IN THE LOWER 60S.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 255 AM TUESDAY...
A PERSISTENT UPPER LOW OVER THE NORTH ATLANTIC WILL LEAD TO FURTHER
AMPLIFICATION OF AN UPPER RIDGE FROM THE LOW MS VALLEY TO THE GREAT
LAKES...WITH CENTRAL NC SANDWICHED BETWEEN THE TWO WAVE FEATURES.
THE SURFACE RIDGE AXIS ALONG THE EAST COAST IS FORECAST TO
STRENGTHEN FRIDAY AND SATURDAY WITH DRIER AIR SETTLING SOUTH INTO
THE CAROLINAS. THE COOLING TREND EXPECTED TO BEGIN THURSDAY WILL
CONTINUE AS LOW LEVEL THICKNESSES ARE PROGGED TO FALL SLIGHTLY EACH
DAY....LEADING TO FORECAST HIGHS IN THE LOWER 80S BOTH DAYS. MODELS
THEN DIVERGE SLIGHTLY AS THE ECMWF SHOWS THE UPEPR RIDGE WEAKENING
MORE RAPIDLY...WITH MCS ACTIVITY TRAVERSING THE OH VALLEY LATE
SUNDAY INTO MONDAY. THE GFS HAS A STRONGER UPPER RIDGE WEST OF THE
MOUNTAINS...BUT ALLOWS SOME ENERGY ON THE WESTERN PERIPHERY OF THE
NORTH ATLANTIC LOW TO DRIFT SOUTHWESTWARD ALONG THE COAST. WITH NO
CLEAR SIGNAL AS TO WHICH FEATURE WILL BECOME DOMINANT...AT LEAST
THROUGH MONDAY...WE WILL KEEP THE FORECAST DRY WITH A SLIGHT
RECOVERY OF TEMPS SUNDAY AND MONDAY.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 150 PM TUESDAY...
24-HR TAF PERIOD:
DIURNAL HEATING/MIXING HAS ALLOWED CEILINGS TO IMPROVE TO MVFR AT
ALL TAF SITES...WITH THE 17Z INT TERMINAL REPORTING VFR CEILINGS.
EXPECT CEILINGS TO GENERALLY RANGE FROM 2000-3500 FT THIS AFTERNOON
GIVEN THE VERY MOIST AIRMASS IN PLACE...WITH MVFR/IFR CONDITIONS
POSSIBLE BETWEEN 18-00Z AT ANY TAF SITE IN ASSOCIATION WITH
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS. GIVEN RELATIVELY
HIGH CHANCES FOR PRECIPITATION...WILL INCLUDE A TEMPO GROUP FOR
SHOWERS AND LOW-END MVFR CONDITIONS AT ALL TAF SITES DURING PEAK
HEATING. WIND GUSTS UP TO 25-35 KT WILL BE POSSIBLE IN ASSOCIATION
WITH ANY THUNDERSTORMS THIS AFTERNOON. THOUGH THE PROBABILITY IS
LOW...ISOLATED CONVECTIVE WIND GUSTS AS HIGH AS 35-50 KT CANNOT BE
RULED OUT AT THE INT/GSO TAF SITES BETWEEN 19-23Z. AFTER SUNSET...
IFR CONDITIONS ASSOCIATED WITH FOG OR LOW CEILINGS WILL BE POSSIBLE
AT ALL TAF SITES GIVEN A VERY MOIST BOUNDARY LAYER...LIGHT/VARIABLE
OR CALM WINDS AND SOME EROSION OF CLOUD COVER AS THE MID-LEVELS
BEGIN TO DRY OUT FROM THE WEST. A COLD (DRY) FRONT WILL APPROACH THE
AREA FROM THE NORTHWEST AFTER MIDNIGHT AND PROGRESS INTO THE N/NW
PIEDMONT BY SUNRISE. IT IS POSSIBLE THAT ENOUGH DRY AIR MAY ADVECT
INTO THE INT/GSO TERMINALS TO IMPROVE CONDITIONS PRIOR TO SUNRISE...
THOUGH UNCERTAINTY REMAINS HIGH. FURTHER SOUTH AND EAST AT THE
RDU/RWI/FAY TERMINALS...MVFR OR IFR CONDITIONS ARE LIKELY TO PREVAIL
THROUGH 12Z WED MORNING. ASIDE FROM LINGERING MVFR CEILINGS AT THE
FAY/RWI TERMINALS WED MORNING...EXPECT VFR CONDITIONS BY THE END OF
THE TAF PERIOD AS A DRIER AIRMASS PROGRESSES INTO THE AREA IN THE
WAKE OF THE FRONT. LIGHT WEST/NW WINDS WILL BECOME NORTHEAST AT
10-15 KT IN THE WAKE OF THE FRONT...PRIMARILY AFTER 12Z WED.
18Z WEDNESDAY THROUGH SUNDAY:
VFR CONDITIONS ARE GENERALLY EXPECTED BEHIND THE FRONT WEDNESDAY
AFTERNOON/NIGHT AS A DRIER AIRMASS SETTLES INTO CENTRAL NC.
HOWEVER...NORTHEAST FLOW OFF THE ATLANTIC MAY LEAD TO MVFR CEILINGS
ACROSS THE AREA (PRIMARILY RDU/RWI/FAY TERMINALS) ON THURSDAY...
THOUGH UNCERTAINTY REMAINS HIGH. NORTHEAST LOW-LEVEL FLOW WILL
PERSIST INTO THE WEEKEND IN ASSOCIATION WITH UNSEASONABLY STRONG
HIGH PRESSURE EXTENDING SOUTHWEST FROM NEW ENGLAND INTO THE
MID-ATLANTIC/CAROLINAS. ALTHOUGH CHANCES FOR PRECIPITATION APPEAR
LOW AT THIS TIME...EXPECT A POTENTIAL FOR MVFR CEILINGS FRIDAY
THROUGH THE WEEKEND GIVEN NE/NNE LOW-LEVEL FLOW. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT/GIH
SHORT TERM...SMITH
LONG TERM...SMITH
AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1236 PM EDT TUE JUN 12 2012
.SYNOPSIS...
A SLOW MOVING STORM SYSTEM LOCATED JUST TO OUR WEST THIS MORNING
WILL BRING NUMEROUS SHOWERS AND A FEW THUNDERSTORMS TO OUR AREA
TODAY. THIS STORM SYSTEM WILL MOVE THROUGH THE REGION LATE
TONIGHT... BRINGING DRIER WEATHER FOR WEDNESDAY INTO FRIDAY.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
AS OF 1230 PM TUESDAY...
OVERVIEW:
A WEAK MID-LEVEL TROUGH CENTERED OVER THE WESTERN CAROLINAS (NEAR
I-77 PER 700 MB 15Z SPC MESOANALYSIS) WILL TRACK SLOWLY EASTWARD
INTO THE CENTRAL CAROLINAS THIS AFTERNOON/EVENING...PROGRESSING TO
THE CAROLINA COAST BY 12Z WED MORNING. IN THE LOWER LEVELS...A
SFC-H85 REFLECTION ATTENDANT THE MID-LEVEL WAVE WILL ALSO PROGRESS
EASTWARD INTO THE CENTRAL CAROLINAS. FURTHER UPSTREAM...A COLD FRONT
EXTENDING SSW FROM THE GREAT LAKES INTO THE WESTERN OH/TN VALLEY AT
15Z THIS MORNING WILL PROGRESS INTO THE SOUTHERN APPALACHIANS BY 00Z
THIS EVENING. THE FRONT WILL SLOW DOWN AND BECOME INCREASINGLY
WEST-EAST ORIENTED TONIGHT...THEN PROGRESS SOUTH THROUGH THE AREA ON
WED AS HIGH PRESSURE STRENGTHENS OVER THE GREAT LAKES AND NORTHERN
MID-ATLANTIC.
PRECIPITATION CHANCES:
DESPITE A VERY MOIST BOUNDARY LAYER WITH SFC DEWPOINTS IN THE LOWER
70S...WEAK MID-LEVEL LAPSE RATES AND EXTENSIVE CLOUD COVER OVER THE
AREA SHOULD TEMPER DIURNAL DESTABILIZATION THIS AFTERNOON ALONG/EAST
OF HWY 1...WHERE 500-1000 J/KG OF MLCAPE IS PROGGED AT BEST. IN THE
WESTERN PIEDMONT...LESS CLOUD COVER AND BETTER INSOLATION WILL LEAD
TO STRONGER DIURNAL DESTABILIZATION...WITH MLCAPE VALUES PROGGED AT
1000-1500 J/KG. BASED ON SPC MESOANALYSIS AND THE LATEST
OBSERVATIONAL DATA...THE LOW/MID-LEVEL TROUGH IN VICINITY OF I-77
OVER THE WESTERN CAROLINAS AT 15Z WILL BE THE PRIMARY FOCUSING
MECHANISM FOR CONVECTION TODAY AS IT PROGRESSES EASTWARD INTO
CENTRAL NC IN THE PRESENCE OF A TROPICAL (PWAT NEAR 2.00") AIRMASS.
15Z VWP DATA FROM SURROUNDING SITES ALREADY SHOW WESTERLY LOW-LEVEL
FLOW AT GSP/RNK/CAE...SUGGESTING THE BEST LOW-LEVEL CONVERGENCE AND
FOCUS FOR CONVECTION TODAY SHOULD REMAIN ALONG AND EAST OF HIGHWAY
1...AND WILL MAINTAIN CATEGORICAL (80%) PRECIPITATION CHANCES IN
THAT AREA. FURTHER WEST THE FORECAST IS MORE UNCERTAIN. ALTHOUGH THE
BEST CONVERGENCE WITH THE LOW/MID-LEVEL TROUGH IS ALREADY IN
VICINITY OF HWY 1...15Z WV IMAGERY SHOWED A SHEAR AXIS PROGRESSING
EASTWARD THROUGH EASTERN KY/CENTRAL TN...AND THE LATEST RAP MODEL
DATA PROGS THIS FEATURE TO PROGRESS INTO THE MOUNTAINS AND FOOTHILLS
LATER THIS AFTERNOON AND EVENING (IN VICINITY OF PEAK HEATING).
ALTERNATELY...DIFFERENTIAL HEATING IN THE PRESENCE OF A VERY MOIST
AIRMASS MAY LEAD TO THE DEVELOPMENT OF ISOLD/SCT CONVECTION IN THE
MOUNTAINS EARLY THIS AFTERNOON...WHICH COULD PROGRESS EAST/SE INTO
THE WESTERN PIEDMONT BY MID TO LATE AFTERNOON VIA 15 KT W/NW
MID-LEVEL FLOW.
THE 00Z AND 06Z HIGH-RES CONVECTION ALLOWING MODELS OFFER VARYING
SOLUTIONS WITH REGARD TO CONVECTION THIS AFTERNOON... RANGING FROM
LITTLE MORE THAN ISOLD CONVECTION IN THE WESTERN PIEDMONT TO THE
DEVELOPMENT OF A SW-NE ORIENTED LINE OF CONVECTION FROM CLT-INT AT
20Z THAT PROGRESSES THROUGH ALL OF CENTRAL NC BY SUNSET.
ADDITIONALLY...LARGE MCS`S UPSTREAM OF THE AREA LAST NIGHT MAY HAVE
ALTERED THE MID-LEVELS IN A MANNER NOT CAPTURED WELL BY THE 00-06Z
MODEL RUNS...ADDING FURTHER UNCERTAINTY TO THE PRECIP FORECAST. WITH
THE ABOVE IN MIND...FEEL THAT IT WOULD BE UNWISE TO REDUCE PRECIP
CHANCES MUCH BELOW WHAT HAS BEEN PREVIOUSLY ADVERTISED IN THE
WESTERN PIEDMONT. AFTER SUNSET...EXPECT CONVECTION TO WEAKEN AND
SHIFT SOUTHEAST IN CONCERT WITH THE MID-LEVEL TROUGH...WITH PRECIP
CHANCES DECREASING AND ENDING FROM NW-SE BY OR SHORTLY AFTER
MIDNIGHT AS A DRIER MID-LEVEL AIRMASS PROGRESSES INTO THE AREA.
SEVERE/FLOODING THREAT:
DO NOT ANTICIPATE A THREAT FOR AREA-WIDE FLOODING GIVEN A LACK OF
WIDESPREAD HEAVY RAIN YESTERDAY (ISOLD AREAS GOT 1-2") AND 1-3 HR
FLASH FLOOD GUIDANCE IN THE 2-4" RANGE IN MOST LOCATIONS (EXCLUDING
URBAN AREAS). HOWEVER...GIVEN THE TROPICAL AIRMASS IN PLACE...
RAINFALL RATES WITH CONVECTION THIS AFTERNOON WILL BE ON THE
HIGH-END...AND A LOCALIZED THREAT FOR FLOODING WILL CERTAINLY BE
PRESENT...PRIMARILY IN URBAN AREAS. ALTHOUGH MODERATE INSTABILITY
WILL BE POSSIBLE IN THE WESTERN PIEDMONT THIS AFT/EVE...DEEP LAYER
SHEAR IS PROGGED TO BE NO HIGHER THAN 15-20 KT...AND ORGANIZED
CONVECTION IS NOT EXPECTED. RELATIVELY BETTER INSOLATION IN THE
WESTERN PIEDMONT MAY YIELD 500-750 J/KG OF DCAPE THIS AFTERNOON...IN
THE PRESENCE OF 1.50"+ PWAT VALUES. THIS COMBINATION OF PRECIP
LOADING AND BOUNDARY LAYER EVAP COOLING COULD RESULT IN ISOLD SEVERE
DOWNBURSTS IN THE WESTERN PIEDMONT BETWEEN 300-800 PM.
TEMPERATURES:
EXTENSIVE CLOUD COVER AND SHOWER ACTIVITY WILL KEEP HIGHS TODAY
SIMILAR TO YESTERDAY...IN THE LOWER 80S...OR 81-85F. LOWS TONIGHT
WILL PRIMARILY DEPEND ON THE PROGRESS OF THE COLD (DRY) FRONT
APPROACHING THE AREA FROM THE NORTHWEST. THE BULK OF MODEL GUIDANCE
AGREES THAT THE FRONT SHOULD MAKE PROGRESS INTO THE N/NW PIEDMONT BY
SUNRISE WED...AND WILL INDICATE LOWS RANGING FROM THE MID/UPPER 60S
N/NW TO ~70F SOUTHEAST. -VINCENT
FOR WEDNESDAY:
THE SURFACE TROUGH IS EXPECTED TO HAVE SHIFTED TO THE COASTAL
CAROLINAS BY WEDNESDAY MORNING WITH MAINLY NORTHERLY FLOW AT 850 MB.
THE MAIN COOL FRONT SHOULD EASE SLOWLY TO THE SSE INTO THE NORTHERN
CWA DURING THE AFTERNOON AS A PORTION OF THE WEAKENING NORTHERN
STREAM MID LEVEL SHORTWAVE DROPS SE TOWARD NC. PW VALUES ARE
EXPECTED TO DROP BACK DOWN TO NEAR NORMAL VALUES AS DRIER AIR
ADVECTS IN FROM THE NNW... MOST MARKEDLY IN THE MID-UPPER LEVELS...
ALTHOUGH ELEVATED PW NEAR 1.5 INCHES WILL LIKELY REMAIN OVER THE
SOUTHEAST CWA. AS A 60-70 KT SWRLY UPPER JET SHIFTS OVER THE
DELMARVA AND NJ... WEAK UPPER DIVERGENCE WEDNESDAY AFTERNOON OVER SE
NC WORKING ON THE LINGERING MOISTURE AND STEEPENING WET BULB LAPSE
RATE MAY LEAD TO SCATTERED SHOWERS AND STORMS HERE... SO WILL LEAVE
IN CHANCE POPS IN THE AFTERNOON WITH DRY CONDITIONS ELSEWHERE WHERE
LOW LEVEL FLOW WILL BECOME NORTH-NORTHEASTERLY. AN ANTICIPATED LOW
LEVEL DRY ADIABATIC LAPSE RATE SUGGESTS WARM HIGHS OF 84-88... WITH
SCATTERED TO BROKEN CONVECTIVE CLOUDS AREAWIDE... MOST NUMEROUS
ACROSS THE EAST AND SOUTH. -GIH
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
AS OF 255 AM TUESDAY...
A COLD FRONT...ATTENDANT TO A WEAK...SOUTHWARD DRIFTING SURFACE LOW
JUST OFFSHORE...WILL PUSH SOUTH THROUGH CENTRAL NC BY THURSDAY
MORNING. HIGH PRESSURE WILL SET UP OVER EASTERN CANADA AND EXTEND
SOUTH ALONG THE EAST COAST WHILE AN UPPER LEVEL RIDGE BUILDS FROM
THE DEEP SOUTH TO THE MIDWEST. FORECAST SOUNDINGS SHOW ENOUGH OF A
NORTHEASTERLY LOW LEVEL FETCH FOR SOME STRATUS THURSDAY
MORNING...ESPECIALLY OVER THE COASTAL PLAIN. DESPITE AN INITIAL
SURGE OF DRIER DEWPOINTS...WHICH ARE CURRENTLY IN THE UPEPR 40S OVER
THE NORTHERN PLAINS...GUIDANCE SHOWS A STRONG RECOVERY DURING THE
DAY WITH DEWPOINTS IN THE LOWER 60S. HOWEVER...MUCH DRIER MID LEVEL
AIR AND STRENGTHENING SUBSIDENCE SHOULD PRECLUDE ANY SHOWERS OR
STORMS. LOW LEVEL THICKNESSES ARE FORECAST TO FALL BELOW 1400M...TO
AS LOW AS 1385M BASED ON THE GFS...LEADING TO HIGHS IN THE LOW TO
MID 80S. PATCHY STRATUS COULD BE POSSIBLE AGAIN THURSDAY
NIGHT...THROUGH THE STRENGTHENING SURFACE RIDGE AXIS MAY HELP TO
KEEP STRATUS SUPPRESSED CLOSER TO THE COAST. LOWS IN THE LOWER 60S.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 255 AM TUESDAY...
A PERSISTENT UPPER LOW OVER THE NORTH ATLANTIC WILL LEAD TO FURTHER
AMPLIFICATION OF AN UPPER RIDGE FROM THE LOW MS VALLEY TO THE GREAT
LAKES...WITH CENTRAL NC SANDWICHED BETWEEN THE TWO WAVE FEATURES.
THE SURFACE RIDGE AXIS ALONG THE EAST COAST IS FORECAST TO
STRENGTHEN FRIDAY AND SATURDAY WITH DRIER AIR SETTLING SOUTH INTO
THE CAROLINAS. THE COOLING TREND EXPECTED TO BEGIN THURSDAY WILL
CONTINUE AS LOW LEVEL THICKNESSES ARE PROGGED TO FALL SLIGHTLY EACH
DAY....LEADING TO FORECAST HIGHS IN THE LOWER 80S BOTH DAYS. MODELS
THEN DIVERGE SLIGHTLY AS THE ECMWF SHOWS THE UPEPR RIDGE WEAKENING
MORE RAPIDLY...WITH MCS ACTIVITY TRAVERSING THE OH VALLEY LATE
SUNDAY INTO MONDAY. THE GFS HAS A STRONGER UPPER RIDGE WEST OF THE
MOUNTAINS...BUT ALLOWS SOME ENERGY ON THE WESTERN PERIPHERY OF THE
NORTH ATLANTIC LOW TO DRIFT SOUTHWESTWARD ALONG THE COAST. WITH NO
CLEAR SIGNAL AS TO WHICH FEATURE WILL BECOME DOMINANT...AT LEAST
THROUGH MONDAY...WE WILL KEEP THE FORECAST DRY WITH A SLIGHT
RECOVERY OF TEMPS SUNDAY AND MONDAY.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
AS OF 738 AM TUESDAY...
IFR/LIFR CONDITIONS ARE LIKELY TO PERSIS IN THE TRIAD THROUGH 14Z
WHEN A SLOW LIFT TO MVFR IS EXPECTED THROUGH 16Z FOLLOWED BY VFR
CONDITIONS AT 18Z. MVFR CIGS AT RDU/RWI/FAY... SIMILARLY... WILL
ALSO SLOWLY LIFT TO VFR BY 17-18Z. A MID LEVEL LOW PRESSURE SYSTEM
AND SURFACE FRONT LOCATED THROUGH THE MID SOUTH AND GULF STATES THIS
MORNING WILL DRIFT SLOWLY EASTWARD THROUGH OUR AREA TODAY AND
TONIGHT. A DEEP MOIST FLOW FROM THE SOUTH AND SW IS RESPONSIBLE FOR
THE CURRENT ADVERSE AVIATION CONDITIONS... AND THIS FLOW PATTERN
WILL PERSIST THROUGH TODAY WITH SLOWLY RISING CIGS THROUGH THE
MORNING. HOWEVER... AS CIGS LIFT... WIDESPREAD SHOWERS AND A FEW
THUNDERSTORMS ARE EXPECTED TO DEVELOP AREAWIDE... AND A PERIOD OF
LOCAL MVFR CIGS -- AND POSSIBLY BRIEFLY IFR -- ARE POSSIBLE IN AND
NEAR ANY SHOWERS/STORMS. THE GREATEST COVERAGE OF SHOWERS/STORMS
WILL BE 17Z-23Z... WITH RAIN EXITING WEST TO EAST LATE AFTERNOON
INTO EARLY EVENING. WITH SKIES STARTING TO CLEAR OUT WEST TO EAST AS
A FRONT MOVES THROUGH CENTRAL NC STARTING LATE THIS EVENING... THE
DAMP GROUND AND LIGHT WINDS MAY FOSTER MVFR TO IFR GROUND FOG
DEVELOPMENT AFTER MIDNIGHT.
LOOKING BEYOND 06Z TONIGHT... MVFR TO IFR GROUND FOG IS LIKELY TO
DISPERSE PRIOR TO 12Z AT INT/GSO BUT MAY LINGER UNTIL SHORTLY AFTER
12Z AT RDU/RWI/FAY. CIGS ARE EXPECTED TO BE VFR WEDNESDAY
AREAWIDE... ALTHOUGH AN ISOLATED LATE DAY STORM IS POSSIBLE MAINLY
AT FAY AND LOCAL BRIEF MVFR CONDITIONS MAY OCCUR. OTHERWISE VFR
CONDITIONS ARE EXPECTED AT ALL FORECAST SITES THROUGH SATURDAY AS
HIGH PRESSURE BUILDS IN FROM THE NORTH. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...VINCENT/HARTFIELD
SHORT TERM...SMITH
LONG TERM...SMITH
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
132 PM CDT TUE JUN 12 2012
.DISCUSSION...
UPDATED FOR 18Z AVIATION DISCUSSION
&&
.PREV DISCUSSION... /ISSUED 1040 AM CDT TUE JUN 12 2012/
UPDATE...
UPDATE TO ADJUST POPS FOR THE REMAINDER OF TODAY.
DISCUSSION...
A COLD FRONT IS CURRENTLY STRETCHED ACROSS NORTHERN PORTIONS OF
THE MID SOUTH THIS MORNING. A DECAYING MESOSCALE CONVECTIVE SYSTEM
(MCS) WILL CONTINUE TO WEAKEN WITH RAIN CHANCES DIMINISHING SLOWLY
ACROSS THE SOUTH. WEAK SHORTWAVE DISTURBANCES EMBEDDED WITHIN
NORTHWEST FLOW ALOFT COMBINED WITH THE SOUTHWARD MOVING FRONT AND
AFTERNOON SURFACE HEATING MAY ALLOW FOR THE REDEVELOPMENT OF
SCATTERED SHOWERS AND THUNDERSTORMS ACROSS EASTERN ARKANSAS AND
NORTHERN MISSISSIPPI THIS AFTERNOON. AS INSTABILITY INCREASES
CANNOT RULE OUT A STRONGER THUNDERSTORM...BUT THINK THE POTENTIAL
FOR ANY SEVERE STORMS IS LOW AS SHEAR IS QUITE WEAK.
UPDATED ZONES...GRIDS...AND HWO WILL BE SENT SHORTLY.
JLH
PREV DISCUSSION... /ISSUED 300 AM CDT TUE JUN 12 2012/
A COLD FRONT CURRENTLY STRETCHES FROM NEAR MOUNT VERNON ILLINOIS
TO NEAR LITTLE ROCK ARKANSAS. CONVECTION THAT OCCURRED EARLIER
THIS EVENING HAS PUSHED ALL THE WAY TO THE GULF COAST. SOME
REDEVELOPMENT IS OCCURRING ACROSS SOUTHERN ARKANSAS IN RESPONSE TO
A SHORTWAVE. THE MOVEMENT OF THESE STORMS ARE TO THE SOUTHEAST
WHICH MOVES THEM INTO PHILLIPS COUNTY ARKANSAS AND PORTIONS OF
NORTHWEST MISSISSIPPI. MODELS INDICATE FURTHER DEVELOPMENT COULD
OCCUR TODAY ALONG AND AHEAD OF THE FRONT. HOWEVER THERE IS SOME
QUESTION ON HOW WORKED OVER THE ATMOSPHERE IS FROM THIS EVENINGS
CONVECTION. THE AREA WILL NOT BE AS UNSTABLE TODAY AS YESTERDAY
AHEAD OF THE FRONT. THE 00Z NAM INDICATES SOME REDEVELOPMENT COULD
OCCUR THIS MORNING ACROSS NORTH MISSISSIPPI BUT SHOULD PUSH SOUTH
OF THE CWA BY EARLY AFTERNOON. THE LATEST RUC AND HRRR RUN SHOWS
SOMETHING SIMILAR TO THE NAM. THE 00Z GFS DID NOT INITIALIZE WELL
WITH WHAT IS CURRENTLY GOING THUS WILL NOT BE USED IN THE SHORT
TERM. THUS WILL LOWER CHANCES FOR SHOWERS AND THUNDERSTORMS TO 40
PERCENT ACROSS MUCH OF NORTH MISSISSIPPI FOR MAINLY THIS MORNING
WITH POSSIBLY LEAVING LIKELY POPS ACROSS PHILLIPS COUNTY AND
PORTIONS OF NORTHWEST MISSISSIPPI THROUGH 7 AM. ELSEWHERE...WILL
REMOVE MENTION OF PRECIPITATION. DRIER AIR WILL BEGIN TO FILTER
INTO NORTHERN PORTIONS OF THE CWA BY THIS AFTERNOON. HIGHS WILL BE
IN THE UPPER 80S.
TONIGHT THROUGH THURSDAY NIGHT...HIGH PRESSURE WILL BUILD INTO THE
AREA FROM THE OHIO VALLEY. DRIER AIR WILL FILTER INTO THE AREA BUT
DO NOT EXPECT MUCH CHANGE IN AT LEAST HIGH TEMPERATURES. HIGHS WILL
STILL BE IN THE MID 80S TO AROUND 90 THROUGH THE PERIOD. LOWS WILL
BE COOLER WITH READINGS IN THE MID 50S TO MID 60S...POSSIBLY A TAD
WARMER THURSDAY NIGHT AS WINDS TURN AROUND TO THE SOUTH.
FRIDAY THROUGH EARLY NEXT WEEK...UPPER RIDGE MOVES OVER THE
MIDSOUTH. 00Z GFS INDICATES DIURNAL HEATING COULD KICK OFF ISOLATED
SHOWERS AND THUNDERSTORMS FRIDAY INTO THE WEEKEND. 00Z ECMWF
SHOWS SOMETHING SIMILAR. FRIDAY SEEMS A LITTLE EARLY FOR MOISTURE
RETURN TO BE ENOUGH TO CAUSE DIURNAL CONVECTION THUS WILL REMOVE POPS.
OTHERWISE...WILL LEAVE CURRENT FORECAST AS IS.
KRM
&&
.AVIATION...
18Z TAF SET
A COLD FRONT IS MOVING SLOWLY ACROSS THE MIDSOUTH TODAY. MOST OF
THE RAIN HAS DISSIPATED AND SCATTERED MVFR CIGS ARE GRADUALLY
IMPROVING TO VFR. VFR CONDS WILL PREVAIL TONIGHT THROUGH 18Z.
WINDS WILL BECOME NNW THIS AFTERNOON AT ABT 8 KTS AND THEN
DIMINISH TO AROUND 5 KTS OVERNIGHT.
SJM
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 87 65 86 66 / 40 10 0 0
MKL 87 59 84 57 / 10 10 0 0
JBR 88 61 86 61 / 10 10 0 0
TUP 84 63 87 62 / 60 10 10 10
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
1255 PM CDT TUE JUN 12 2012
.AVIATION...
FOR THE 18Z TAFS...THE PRIMARY CONCERN WILL BE THE TIMING OF TSRA
ACROSS THE REGION. THOUGH THERE IS A CHANCE FOR STORMS THROUGH THE
ENTIRE TAF PERIOD...THE MAIN IMPACT TO THE TERMINALS IS EXPECTED TO
BE A 2 TO 4 HOUR PERIOD AS A CONVECTIVE COMPLEX THAT SHOULD DEVELOP
IN EASTERN NM/CO MOVES E OR ESE INTO THE PANHANDLES. THIS COMPLEX
COULD MOVE INTO THE WESTERN PANHANDLES...INCLUDING KDHT...AS EARLY AS
22 OR 23Z. IT WILL LIKELY NOT AFFECT THE CENTRAL
PANHANDLES...INCLUDING KAMA AND KGUY...UNTIL AFTER 00Z. MVFR...OR
EVEN IFR VISIBILITIES WITH HEAVY RAIN...VARIABLE AND GUSTY
WINDS...AND POSSIBLY SOME HAIL WILL BE POSSIBLE WITH THE STRONGEST
STORMS IN THIS COMPLEX. THOUGH ADDITIONAL STORMS BOTH BEFORE AND
AFTER THIS PERIOD CAN NOT BE RULED OUT...TOO MUCH UNCERTAINTY TO
INCLUDE IN THE TAFS AT THIS TIME.
ANOTHER CONCERN WILL BE THE POSSIBILITY OF BR OR LOW CEILINGS
DEVELOPING AFTER 06Z...ONCE THE STORMS HAVE PASSED. THE HIGHEST
THREAT FOR THIS WILL BE IN KAMA AND KGUY ESPECIALLY IF WINDS REMAIN
SOUTHEASTERLY...AND THEY GET ADDITIONAL RAIN. HOWEVER...WINDS MAY
ALSO REMAIN TO BREEZY TO SEE MUCH BR DEVELOPMENT. FOR NOW HAVE LEFT
OUT OF THE TAFS DUE TO HIGH UNCERTAINTY.
JOHNSON
&&
.PREV DISCUSSION... /ISSUED 1216 PM CDT TUE JUN 12 2012/
UPDATE...
HAVE UPDATED THE FORECAST TO ADJUST THE POPS A LITTLE FOR THIS
AFTERNOON AND THIS EVENING. THE THINKING IS NOW THAT THE BEST CHANCE
OF THUNDERSTORMS WILL BE IN THE NORTHWEST BEFORE 00Z AHEAD OF A SHORT
WAVE TROUGH EJECTING EAST FROM NORTH CENTRAL NEW MEXICO. THEN THIS
ACTIVITY SHOULD SPREAD SOUTHEAST FROM THERE OVERNIGHT INTO THE BETTER
MOISTURE AND INSTABILITY AXIS. ALSO ADDED A SEVERE MENTION TO THE
STORMS GIVEN THE AMOUNT OF SHEAR AND INSTABILITY.
PREV DISCUSSION... /ISSUED 654 AM CDT TUE JUN 12 2012/
AVIATION...
FOR THE 12Z TAFS...ONGOING SHOWERS AND TSTMS AT KAMA WILL CONTINUE
UNTIL AROUND MID MORNING. MAJORITY OF PRECIPITATION SHOULD BYPASS
KDHT AND KGUY THIS MORNING. A LULL IN THE SHOWERS AND TSTMS IS
EXPECTED BY EARLY THIS AFTERNOON. NEXT ROUND OF STORMS TO DEVELOP
SOMETIME LATE THIS AFTERNOON OR EVENING...DEPENDING ON HOW LONG IT
TAKES THE ATMOSPHERE TO RECOVER FROM MORNING TSTMS. FOR THIS
REASON... HAVE DECIDED NOT TO INSERT TSTMS AT ANY TAF SITE AFTER THIS
MORNING DUE TO LOW CONFIDENCE IN HOW MESOSCALE SITUATION WILL EVOLVE
LATER TODAY AND TONIGHT. FUTURE SHIFTS MAY NEED TO CONSIDER ADDING
TSTMS TO ONE OR MORE OF THE TAFS IF CONDITIONS BECOME MORE CLEAR CUT.
ANDRADE
PREV DISCUSSION... /ISSUED 444 AM CDT TUE JUN 12 2012/
DISCUSSION...
AN ACTIVE AND WET WX PATTERN IS TAKING SHAPE ACROSS THE AREA AS
FIRST ROUND OF SHOWERS AND THUNDERSTORMS ARE CURRENTLY MOVING ACROSS
PORTIONS OF THE FA. THESE STORMS WERE BECOMING MORE UPSCALE AS THEY
ENCOUNTER A MORE BUOYANT AIR MASS PER LAPS AND RAP DATA INDICATING
MUCAPES AROUND 200-600 J/KG. DIVERGENCE PROVIDED BY THE RRQ OF A JET
STREAK AND LFQ OF A JET STREAK NOSING INTO THE PANHANDLES ARE ALSO
HELPING TO INTENSIFY THESE STORMS. THESE STORMS WILL CONTINUE
THROUGH THE NEXT FEW HOURS WHERE 0-6 KM BULK SHEAR AROUND 30-40 KTS
AND STEEP MID-LEVEL LAPSE RATES CAN RESULT IN SOME OF THESE STORMS
TO BECOME SEVERE.
LATER TODAY...EXPECT A BIT OF A LULL IN THUNDERSTORM ACTIVITY ONCE
THIS EARLY MORNING CONVECTION EXITS THE AREA. HOWEVER SUFFICIENT LOW-
LEVEL MOISTURE WILL BE MAINTAINED ACROSS THE AREA ON BREEZY SOUTHEAST
SURFACE WINDS. SEVERAL UPPER-LEVEL DISTURBANCES WILL ALSO TRAVERSE
THE SOUTHERN PLAINS TODAY PROVIDING WEAK UPPER LIFT WHILE ANY
OUTFLOW BOUNDARIES CAN PROVIDE A FOCUS FOR STORM DEVELOPMENT.
FORECAST SOUNDINGS INDICATE THE AIR MASS WILL BE VERY UNSTABLE WITH
MLCAPES AROUND 2000-3000 J/KG. SHEAR WILL REMAIN MORE THAN ADEQUATE
TO ALLOW SOME STORMS TO BECOME SEVERE AND EXPECT THE MAIN SEVERE
THREATS TO BE LARGE HAIL AND STRONG WINDS. CONVECTION WILL BECOME
MORE WIDESPREAD TONIGHT AS A LOW-LEVEL JET SETTING UP ACROSS THE
SOUTHERN PLAINS WILL HELP TO MAINTAIN AND WARM...MOIST...AND
UNSTABLE AIR MASS ACROSS THE AREA. HIGHS TODAY SHOULD BE A LITTLE
COOLER...IN THE 80S.
ON WEDNESDAY THE SURFACE FLOW WILL TREND MORE TO THE SOUTH AS A COLD
FRONT THAT IS CURRENTLY SOUTH OF THE AREA LIFTS NORTH. WEAK MID-
LEVEL RIDGING WILL BUILD ACROSS THE SOUTHERN PLAINS HOWEVER SEVERAL
UPPER DISTURBANCES WILL QUICKLY BREAK DOWN THE RIDGE. MOIST AND
UNSTABLE CONDITIONS WILL REMAIN ACROSS THE AREA SO WILL CONTINUE
CHANCE POPS IN THE FORECAST. HAVE ALSO CONTINUED MENTION OF THUNDER
IN THE FORECAST THROUGH THE WEEKEND AS THE DRYLINE SHOULD REMAIN
WEST OF THE AREA WHILE SOUTHWEST UPPER FLOW TAPS INTO THE TROPICAL
MOISTURE OUT OF THE PACIFIC. STILL FAVOR BETTER CHANCES FOR STORMS
TO BE IN THE WEST AND CENTRAL SECTIONS OF THE FA GIVEN THE FORECAST
POSITION OF THE DRYLINE. THE STRENGTHENING OF A LEE TROUGH AND
POSSIBLE EASTWARD MOVEMENT OF THE DRYLINE EARLY NEXT WEEK SHOULD
END THUNDER CHANCES WITH THE NEXT POSSIBLE COLD FRONTAL INTRUSION
COMING AROUND MID-WEEK.
CLK
FIRE WEATHER...
ABUNDANT ATMOSPHERIC MOISTURE AND CHANCES FOR PRECIPITATION THROUGH
MUCH OF THE 7 DAY FORECAST PERIOD WILL PRECLUDE ELEVATED OR CRITICAL
FIRE WEATHER CONDITIONS ACROSS THE TX/OK PANHANDLES.
CLK
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
16/15
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
1216 PM CDT TUE JUN 12 2012
.UPDATE...
HAVE UPDATED THE FORECAST TO ADJUST THE POPS A LITTLE FOR THIS
AFTERNOON AND THIS EVENING. THE THINKING IS NOW THAT THE BEST CHANCE
OF THUNDERSTORMS WILL BE IN THE NORTHWEST BEFORE 00Z AHEAD OF A SHORT
WAVE TROUGH EJECTING EAST FROM NORTH CENTRAL NEW MEXICO. THEN THIS
ACTIVITY SHOULD SPREAD SOUTHEAST FROM THERE OVERNIGHT INTO THE BETTER
MOISTURE AND INSTABILITY AXIS. ALSO ADDED A SEVERE MENTION TO THE
STORMS GIVEN THE AMOUNT OF SHEAR AND INSTABILITY.
&&
.PREV DISCUSSION... /ISSUED 654 AM CDT TUE JUN 12 2012/
AVIATION...
FOR THE 12Z TAFS...ONGOING SHOWERS AND TSTMS AT KAMA WILL CONTINUE
UNTIL AROUND MID MORNING. MAJORITY OF PRECIPITATION SHOULD BYPASS
KDHT AND KGUY THIS MORNING. A LULL IN THE SHOWERS AND TSTMS IS
EXPECTED BY EARLY THIS AFTERNOON. NEXT ROUND OF STORMS TO DEVELOP
SOMETIME LATE THIS AFTERNOON OR EVENING...DEPENDING ON HOW LONG IT
TAKES THE ATMOSPHERE TO RECOVER FROM MORNING TSTMS. FOR THIS
REASON... HAVE DECIDED NOT TO INSERT TSTMS AT ANY TAF SITE AFTER THIS
MORNING DUE TO LOW CONFIDENCE IN HOW MESOSCALE SITUATION WILL EVOLVE
LATER TODAY AND TONIGHT. FUTURE SHIFTS MAY NEED TO CONSIDER ADDING
TSTMS TO ONE OR MORE OF THE TAFS IF CONDITIONS BECOME MORE CLEAR CUT.
ANDRADE
PREV DISCUSSION... /ISSUED 444 AM CDT TUE JUN 12 2012/
DISCUSSION...
AN ACTIVE AND WET WX PATTERN IS TAKING SHAPE ACROSS THE AREA AS
FIRST ROUND OF SHOWERS AND THUNDERSTORMS ARE CURRENTLY MOVING ACROSS
PORTIONS OF THE FA. THESE STORMS WERE BECOMING MORE UPSCALE AS THEY
ENCOUNTER A MORE BUOYANT AIR MASS PER LAPS AND RAP DATA INDICATING
MUCAPES AROUND 200-600 J/KG. DIVERGENCE PROVIDED BY THE RRQ OF A JET
STREAK AND LFQ OF A JET STREAK NOSING INTO THE PANHANDLES ARE ALSO
HELPING TO INTENSIFY THESE STORMS. THESE STORMS WILL CONTINUE
THROUGH THE NEXT FEW HOURS WHERE 0-6 KM BULK SHEAR AROUND 30-40 KTS
AND STEEP MID-LEVEL LAPSE RATES CAN RESULT IN SOME OF THESE STORMS
TO BECOME SEVERE.
LATER TODAY...EXPECT A BIT OF A LULL IN THUNDERSTORM ACTIVITY ONCE
THIS EARLY MORNING CONVECTION EXITS THE AREA. HOWEVER SUFFICIENT LOW-
LEVEL MOISTURE WILL BE MAINTAINED ACROSS THE AREA ON BREEZY SOUTHEAST
SURFACE WINDS. SEVERAL UPPER-LEVEL DISTURBANCES WILL ALSO TRAVERSE
THE SOUTHERN PLAINS TODAY PROVIDING WEAK UPPER LIFT WHILE ANY
OUTFLOW BOUNDARIES CAN PROVIDE A FOCUS FOR STORM DEVELOPMENT.
FORECAST SOUNDINGS INDICATE THE AIR MASS WILL BE VERY UNSTABLE WITH
MLCAPES AROUND 2000-3000 J/KG. SHEAR WILL REMAIN MORE THAN ADEQUATE
TO ALLOW SOME STORMS TO BECOME SEVERE AND EXPECT THE MAIN SEVERE
THREATS TO BE LARGE HAIL AND STRONG WINDS. CONVECTION WILL BECOME
MORE WIDESPREAD TONIGHT AS A LOW-LEVEL JET SETTING UP ACROSS THE
SOUTHERN PLAINS WILL HELP TO MAINTAIN AND WARM...MOIST...AND
UNSTABLE AIR MASS ACROSS THE AREA. HIGHS TODAY SHOULD BE A LITTLE
COOLER...IN THE 80S.
ON WEDNESDAY THE SURFACE FLOW WILL TREND MORE TO THE SOUTH AS A COLD
FRONT THAT IS CURRENTLY SOUTH OF THE AREA LIFTS NORTH. WEAK MID-
LEVEL RIDGING WILL BUILD ACROSS THE SOUTHERN PLAINS HOWEVER SEVERAL
UPPER DISTURBANCES WILL QUICKLY BREAK DOWN THE RIDGE. MOIST AND
UNSTABLE CONDITIONS WILL REMAIN ACROSS THE AREA SO WILL CONTINUE
CHANCE POPS IN THE FORECAST. HAVE ALSO CONTINUED MENTION OF THUNDER
IN THE FORECAST THROUGH THE WEEKEND AS THE DRYLINE SHOULD REMAIN
WEST OF THE AREA WHILE SOUTHWEST UPPER FLOW TAPS INTO THE TROPICAL
MOISTURE OUT OF THE PACIFIC. STILL FAVOR BETTER CHANCES FOR STORMS
TO BE IN THE WEST AND CENTRAL SECTIONS OF THE FA GIVEN THE FORECAST
POSITION OF THE DRYLINE. THE STRENGTHENING OF A LEE TROUGH AND
POSSIBLE EASTWARD MOVEMENT OF THE DRYLINE EARLY NEXT WEEK SHOULD
END THUNDER CHANCES WITH THE NEXT POSSIBLE COLD FRONTAL INTRUSION
COMING AROUND MID-WEEK.
CLK
FIRE WEATHER...
ABUNDANT ATMOSPHERIC MOISTURE AND CHANCES FOR PRECIPITATION THROUGH
MUCH OF THE 7 DAY FORECAST PERIOD WILL PRECLUDE ELEVATED OR CRITICAL
FIRE WEATHER CONDITIONS ACROSS THE TX/OK PANHANDLES.
CLK
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
16/15