Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/17/12
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
300 PM MDT FRI JUN 15 2012
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 300 PM MDT FRI JUN 15 2012
CONVECTION GOT OFF TO AN EARLIER START TODAY WITH ISOLATED STORMS
FORMING OVER THE FLAT TOPS AND EASTERN END OF THE ROAN PLATEAU. A
BIT MORE MOISTURE AVAILABLE IN THE 12Z GJT SOUNDING (0.58 INCHES
LIQUID) COMBINED WITH A WEAK SHORTWAVE IN THE SOUTHWESTERLIES...
EVIDENT IN RAP ANALYSES...PROVIDES SOME INSIGHT INTO EARLY ONSET OF
STORMS. EXPECT STORMS TO SPREAD INTO THE REMAINDER OF THE DIVIDE
MOUNTAINS AND EASTERN UINTA MOUNTAINS AS PEAK HEATING STILL A
COUPLE OF HOURS OFF.
DIURNAL COOLING WILL BRING AN END TO SHOWER AND THUNDERSTORM
ACTIVITY BY...OR SHORTLY AFTER SUNSET AS INSUFFICIENT MOISTURE AND
LIFT TO SUSTAIN IT. LATER THIS EVENING AN EASTWARD PROPAGATING
SHORTWAVE WILL PASS TO THE NORTH OF THE FORECAST AREA DRIVING THE
STALLED FRONT SOUTHWARD. MODELS TAKE THE FRONT TO THE NORTHERN
REACHES OF THE TAVAPUTS AND ROAN PLATEAUS AND INTO THE WHITE RIVER
NATIONAL FOREST BY SUNRISE SATURDAY. LIKE EARLIER IN THE WEEK...
THE FRONT WILL PASS THROUGH WITHOUT FANFARE BRINGING A SHIFT IN
SURFACE WINDS TO THE NORTH AND LITTLE ELSE TO MARK ITS PASSAGE.
ON SATURDAY...THE FRONT AGAIN LIFTS NORTHWARD AND WEAKENS. THE
FORECAST AREA WILL REMAIN BENEATH THE COL BETWEEN THE LOW OVER THE
DESERT SOUTHWEST AND THE PREVAILING WESTERLIES TO THE NORTH. AS
SUCH...MOISTURE TRAPPED OVER THE AREA WILL FUEL ANOTHER ROUND OF
AFTERNOON AND EARLY EVENING HIGH BASED SHOWERS AND THUNDERSTORMS
...MAINLY OVER THE HIGHER TERRAIN.
LATER ON SATURDAY NIGHT...FLOW WILL SHIFT TO THE WEST AS A BROAD
FLAT TROUGH SETTLES OVER THE NORTHWESTERN U.S. THIS SHIFT IN FLOW
WILL DRIVE MUCH OF THE MOISTURE OVER THE REGION EAST OF THE
DIVIDE. THE TROUGH CONTINUES TO SAG SOUTHWARD ON SUNDAY TIGHTENING
THE HEIGHT GRADIENT ACROSS THE NORTH. AS A RESULT...WINDS ARE
EXPECTED TO INCREASE WHILE MOISTURE DIMINISHES. CRITICAL FIRE
WEATHER CONDITIONS ARE POSSIBLE UNDER THIS REGIME AND A FIRE
WEATHER WATCH HAS BEEN ISSUED. FURTHER DETAILS BELOW IN THE FIRE
WEATHER SECTION OF THIS PRODUCT. DRYING PRECLUDES THUNDERSTORM
DEVELOPMENT SO LEFT ANY MENTION OF MOIST CONVECTION OUT OF THE
FORECAST.
TEMPERATURES WILL REMAIN UNSEASONABLY WARM/HOT THIS WEEKEND. WENT
WITH NEAR PERSISTENCE HIGHS SATURDAY AS FLOW REMAINS LIGHT AND 7H
TEMP FIELDS LARGELY UNCHANGED. BOOSTED HIGHS SEVERAL DEGREES ON
SUNDAY AS WINDS MIX DOWN ADDED WARMTH. SOME AREAS WILL LIKELY HIT
THE CENTURY MARK FOR THE FIRST TIME THIS YEAR. OVERNIGHT LOWS WILL
CONTINUE TO HOVER NEAR NORMAL.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 300 PM MDT FRI JUN 15 2012
A STRONG WEST TO SOUTHWEST FLOW WILL PERSIST OVER THE AREA AS THE
SOUTHERN EXTENT OF THE UPPER TROUGH SAGS ACROSS THE CENTRAL ROCKIES
DURING THE FIRST HALF OF THE WEEK. DURING EACH AFTERNOON THIS
STRONGER FLOW WILL MIX TO THE SURFACE FOR BREEZY TO WINDY
CONDITIONS...ESPECIALLY OVER THE NORTH. THIS FLOW WILL SCOUR OUT ANY
OF THE SCANT MOISTURE LINGERING NEAR THE DIVIDE...FOR VERY DRY
CONDITIONS ACROSS THE ENTIRE FORECAST AREA. THEREFORE THE MAIN
CONCERN FOR THIS PERIOD WILL PERTAIN TO FIRE WEATHER. SEE FIRE
WEATHER DISCUSSION BELOW.
THERE CONTINUES TO BE SOME UNCERTAINTY AS TO HOW LONG THE TROUGH
WILL REMAIN TO OUR NORTH. MODELS HAVE INDICATED WE SHOULD BEGIN TO
SEE A LIGHTER FLOW BEGINNING ON WED...BUT IT STILL LOOKS LIKE
ANOTHER SHORTWAVE WILL DROP INTO THE BASE OF THE TROUGH TO OUR
NORTHWEST...BEFORE THE ENTIRE SYSTEM SHIFTS EAST ON THU. FOR NOW
WILL STAY WITH THE DOWNTURN IN THE WINDS ON WED...BUT WITH LOW
CONFIDENCE. HIGH PRESSURE BUILDS OVER THE REGION ON THU INTO
FRI...BRINGING A RELIEF FROM THE WINDS. BUT DRY AND VERY WARM TO HOT
CONDITIONS WILL PERSIST.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 300 PM MDT FRI JUN 15 2012
PERSISTENT PATTERN WILL HOLD ACROSS THE REGION THROUGH THE NEXT
24 HOURS. CONSEQUENTLY...EXPECT ISOLATED THUNDERSTORMS OVER
HIGHER TERRAIN DURING THE EARLY EVENING TO DISSIPATE BY OR SHORTLY
AFTER SUNSET. MAIN THREAT FOR STORMS REMAINS OVER THE CONTINENTAL
DIVIDE AND THE EASTERN UINTA MOUNTAINS. STORMS WILL CONTINUE TO
BE HIGH BASED GENERATING GUSTY OUTFLOW WINDS WITH LITTLE
PRECIPITATION REACHING THE SURFACE. LOOK FOR SIMILAR CONDITIONS
SATURDAY AFTERNOON AS WELL. AS IN PAST DAYS...THERE IS LITTLE
CHANCE THAT THESE STORMS WILL IMPACT AREA TAF SITES. ASIDE FROM
LOCALIZED STORMS OVER HIGHER TERRAIN...VFR CONDITIONS WILL PREVAIL
THROUGH 00Z SATURDAY.
&&
.FIRE WEATHER...
ISSUED AT 300 PM MDT FRI JUN 15 2012
THE SOUTHERN EXTENT OF A BROAD TROUGH ACROSS THE NORTHERN TIER
STATES WILL REACH SOUTHWARD INTO OUR FORECAST ARE BEGINNING ON
SUNDAY. AS A RESULT WEST TO SOUTHWEST FLOW ALOFT WILL INCREASE AS
THE JET STREAM SAGS TOWARDS THE CENTRAL ROCKIES. AT THE SURFACE
BREEZY TO WINDY CONDITIONS WILL DEVELOP EACH AFTERNOON BEGINNING ON
SUNDAY...UNTIL AFTER THE MAIN TROUGH SHIFTS EAST. ALSO CONDITIONS
WILL REMAIN DRY ON THE SOUTHERN SIDE OF THE JET. THEREFORE A FIRE
WEATHER WATCH HAS BEEN ISSUED FOR SUNDAY AND MONDAY AFT/EVE FOR THE
NORTHERN ZONES...WHICH WILL BE FAVORED FOR THE STRONGEST WINDS.
HOWEVER UNCERTAINTY CONTINUES CONCERNING THE SOUTHERN EXTENT OF THE
STRONGER WINDS. IT LOOKS LIKE AFTERNOON WINDS WILL CONTINUE THROUGH
TUESDAY...AND POSSIBLY WEDNESDAY BEFORE THE NORTHERN TROUGH SHIFTS
EAST. THEN LIGHTER WINDS WILL BE EXPECTED LATE IN THE WEEK.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...FIRE WEATHER WATCH FROM SUNDAY AFTERNOON THROUGH SUNDAY EVENING
FOR COZ200>203.
FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING
FOR COZ200>203.
UT...FIRE WEATHER WATCH FROM SUNDAY AFTERNOON THROUGH SUNDAY EVENING
FOR UTZ482>487.
FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING
FOR UTZ482>487.
&&
$$
SHORT TERM...NL
LONG TERM...EH
AVIATION...NL
FIRE WEATHER...EH
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1008 PM CDT SAT JUN 16 2012
.MESOSCALE DISCUSSION...
947 PM CDT
HAVE CLEARED ABOUT THE NORTHERN HALF OF THE CWA FROM SEVERE
THUNDERSTORM WATCH. OBJECTIVE ANALYSIS AS WELL AS RADAR/SATELLITE
IMAGERY SUGGEST THAT SUFFICIENT CINH IS IN PLACE TO PREVENT SEVERE
THUNDERSTORM DEVELOPMENT NORTH OF I-80. HAVE OPTED TO LEAVE COOK
COUNTY IN THE WATCH SINCE SOME STRONGER CELLS IN NORTHWEST WILL
COUNTY WILL BE MOVING THROUGH IN THE NEXT 30-60 MINS. FARTHER
SOUTH OVER SOUTHERN PORTIONS OF THE CWA THE SEVERE THREAT ALSO
APPEARS TO BE DIMINISHING AS PREVIOUS STORMS AND OUTFLOW HAVE
LIKELY RESULTED IN MORE STABLE CONDITIONS. WILL HANG ON TO THE
SEVERE THUNDERSTORM WATCH FOR THESE AREAS THOUGH AS THERE IS STILL
SOME STRONG STORMS WITHIN THE LINE AND IT IS NOT OUT OF THE
QUESTION THAT THERE COULD BE SOME RE-INTENSIFICATION. IF CLOUD
TOPS CONTINUE TO COOL AND STORMS CONTINUE TO WEAKEN THEN THE
REMAINDER OF THE WATCH MAY BE ABLE TO BE CANCELLED EARLY.
IZZI
&&
.DISCUSSION...
330 PM CDT
A FEW AREAS OF CONCERN OVER THE COMING DAYS. THE FIRST WILL BE THE
POTENTIALLY SEVERE WEATHER THIS EVENING...FOLLOWED BY VERY HOT
WEATHER OPENING UP THE WORK WEEK. FOLLOWING THE SHOWERS AND
THUNDERSTORMS TONIGHT...THE NEXT CHANCE FOR PRECIPITATION WILL NOT
BE UNTIL LATER IN THE WEEK.
IN THE SHORT TERM...GOING THREAT FOR MORE OF AN EXPANDED
COVERAGE OF SHOWERS AND THUNDERSTORMS WILL BE ON THE INCREASE.
SYNOPTIC COLD FRONT WELL TO THE WEST AND ACROSS THE PLAINS AND
TIED TO A LOW LIFTING ACROSS CANADA IS SLOWLY SHIFTING TO THE
EAST. THIS FRONT WILL CONTINUE TO MOVE TOWARDS THE REGION
TONIGHT...BUT WEAKEN CONSIDERABLY BY THE TIME IT REACHES EASTERN
IOWA TONIGHT.
FOR THE IMMEDIATE AFTERNOON...SOUTHWESTERLY FLOW HAS ALLOWED A
RATHER LARGE SURGE OF MOISTURE TO BE TRANSPORTED ACROSS THE REGION.
OUTSIDE OF AREAS THAT SAW RAIN THIS MORNING...DEWPOINTS HAVE JUMPED
FROM AROUND 50 DEGREES TO THE MIDDLE AND UPPER 60S. FORECAST
SOUNDINGS NOT INDICATING MUCH DRY AIR TO IMPEDE THE CLIMB...AND
HAVE NUDGED DEWPOINTS UP ACROSS THE AREA. THE HIGHEST AXIS OF
INSTABILITY IS GENERALLY ANTICIPATED TO REMAIN SOUTH OF THE
AREA...AND CLOSER TO THE IOWA/ILLINOIS/MISSOURI JUNCTION...BUT
MUCAPE VALUES IN THE 1500 TO 2000 J/KG RANGE ARE STILL LIKELY
ACROSS THE EAST THIS AFTERNOON AND UP TO THE WI BORDER. OVERALL
SHEAR IS LOW...AND TIED CLOSER TO THE WAVE LIFTING ACROSS
WISCONSIN. GENERALLY EXPECTING THE SMALL...BUT EFFICIENT RAIN
PRODUCING SHOWERS AND THUNDER TO CONTINUE TO BUBBLE THIS AFTERNOON.
THE GREATEST CHANCES THROUGH AFTERNOON DO APPEAR TO BE EAST OF THE
I57 CORRIDOR...AND WEST OF I39.
THE PRIMARY FOCUS LATER THIS AFTERNOON AND INTO THE EVENING WILL BE
TIED TO A STRONG WAVE THAT IS SLIDING ACROSS THE MISSOURI AND IOWA
BORDER THIS AFTERNOON. PRESENTLY...SHOWER AND THUNDERSTORM CLUSTERS
ARE INCREASING IN OVERALL COVERAGE WITH AND AHEAD OF THIS FEATURE. THE
HIGHEST INSTABILITY AXIS IS WEST AND ACROSS THE MO/IA/IL BORDER
REGION...WITH RAP ANALYZED VALUES NEARING THE 3-4000 MARK. SHEAR
WILL INCREASE AS THE WAVE APPROACHES...AND THE CLUSTER OF STORMS
WILL INCREASE IN COVERAGE AS THEY SHIFT EAST...AND INTO A
SUPPORTIVE ENVIRONMENT. FORECAST SOUNDINGS AND MORNING RAOBS
SHOW A CONSIDERABLE INCREASE OF MOISTURE...WITH PWAT VALUES
JUMPING 2/3 TO 3/4 OF AN INCH ABOVE THEIR MORNING VALUES /AND
PEAKING AROUND THE 1.9 INCH RANGE. AS WAS SEEN EARLIER IN THE
DAY...IT DOES NOT TAKE MUCH FOR THESE STORMS TO PUT OUT A LOT OF
PRECIPITATION. THE LATEST HRRR HAS BEEN A DECENT PROXY FOR
COVERAGE AND TIMING...AND ANTICIPATE COVERAGE TO INCREASE FOR
ROCKFORD BEYOND THE 6P HOUR AND A FEW HOURS BEYOND FOR CHICAGO.
HEAVY RAIN IS THE BIGGEST THREAT WITH THESE STORMS...BUT SOME
POCKETS MAY CONTAIN SUB TO MARGINALLY SEVERE HAIL AND STRONG
WINDS ARE POSSIBLE...THOUGH DIURNALLY BY THE TIME THEY REACH THE
MAJORITY OF THE CWA...IT WILL BE GETTING INTO AN UNFAVORABLE TIME.
THE RAIN WILL BE WELCOME FOR MANY AREAS...BUT OVERALL DROUGHT
BUSTING ONES ARE NOT A LIKELIHOOD.
LONG TERM...THE JET ENGINE WILL TURN ON. THE COLD FRONT THAT IS
MARCHING EAST ACROSS THE MISSISSIPPI VALLEY TODAY WILL BASICALLY
WASH OUT AND ONLY DROP DEWPOINTS DOWN INTO THE LOWER 60S TO UPPER
50S...AND KEEP HIGH TEMPERATURES INTO THE 80S TOMORROW. BIG H8
THERMAL RIDGE WILL SLOWLY SHIFT EAST FROM THE PLAINS AND CLOSE TO
THE REGION...WARMING THE AREA BACK UP MONDAY. ENDED UP BUMPING UP HIGHS
FOR BOTH MONDAY AND TUESDAY TO BE INTO THE UPPER 90 RANGE /AND CAN
SEE A POSSIBLE 100 MARK SOMEWHERE ACROSS THE REGION/ IN THAT TIME.
NOT ONLY WILL IT BE HOT ON MONDAY...IT WILL BE INCREDIBLY WINDY.
FORECAST SOUNDINGS SHOW MIXED LAYER WINDS BREACHING THE 30KT
RANGE. THE POTENTIAL FOR CRITICAL FIRE WEATHER CONDITIONS WILL BE
ELEVATED...BUT SPECIFICS WILL BE FOLLOWED UP IN THE FIRE WEATHER
DISCUSSIONS THROUGH THE WEEKEND. THE 90S WILL CONTINUE THROUGH
WEDNESDAY...BEFORE A FRONT MOVES THROUGH THURSDAY AND COOLS OFF
THE AREA WITH THE NEXT CHANCE FOR SHOWERS AND STORMS.
SHEA
&&
.FIRE WEATHER...
515 PM CDT
HOT AND WINDY CONDITIONS MAY RESULT IN CRITICAL AND DANGEROUS
FIRE WEATHER CONDITIONS ON MONDAY.
FOR THE REMAINDER OF THIS AFTERNOON AND THIS EVENING...INCREASING
DEWPOINTS ACROSS THE AREA WILL LIMIT MINIMUM RELATIVE HUMIDITY
VALUES TO 35 TO 40 PERCENT AS TEMPERATURES TOP OUT IN THE LOWER
90S. WINDS WILL OUT OF THE SOUTHWEST AT 10 TO 15 MPH...GUSTING
TO AROUND 20 MPH.
SCATTERED SHOWERS AND THUNDERSTORMS WILL BRING WETTING RAIN TO
SOME LOCATIONS THROUGH EARLY THIS EVENING. THERE IS THE POTENTIAL
FOR ADDITIONAL THUNDERSTORMS THROUGH LATE THIS EVENING WHICH MAY
BRING SOME ADDITIONAL WETTING RAIN...AND SOME THUNDERSTORMS MAY
EVEN BRING SOME LOCALLY HEAVY RAINFALL.
WHILE RED FLAG CRITERIA WILL NOT BE REACHED TODAY...THE RECENT
VERY DRY CONDITIONS COMBINED WITH HIGH TEMPERATURES...MODESTLY
LOW DEW POINTS AND MODERATELY STRONG WINDS WILL RESULT IN ELEVATED
WILDFIRE DANGER.
A WEAK...COLD FRONT WILL MOVE INTO THE AREA TONIGHT AND EARLY
SUNDAY MORNING...BRINGING SLIGHTLY COOLER AIR...WITH HIGHS IN THE
MID AND UPPER 80S.
MUCH WARMER AIR WILL RETURN MONDAY WITH SOUTHWEST WINDS GUSTING AS
HIGH AS 40 MPH. SOME QUESTION REMAINS AS TO HOW LOW DEWPOINTS MAY
MAY DROP MONDAY AFTERNOON IF DRIER AIR ALOFT MIXES DOWN TO THE
SURFACE. CURRENTLY...EXPECT THAT HIGH TEMPERATURES WILL BE IN THE
MIDDLE 90S. EVEN DEWPOINTS IN THE LOWER 60S WILL CAUSE RELATIVE
HUMIDITY VALUES TO DROP CLOSE TO 30 PERCENT OVER MUCH OF THE AREA
AND DEWPOINTS IN THE UPPER 50S WILL BRING RELATIVE HUMIDITY LEVELS
IN RED FLAG CRITERIA RANGE.
ANOTHER WILD CARD IS HOW RAINFALL OCCURRING THIS AFTERNOON AND HOW
MUCH ADDITIONAL RAINFALL THAT MAY OCCUR LATER THIS EVENING WILL
AFFECT FUEL MOISTURE LEVELS AS WELL AS SOIL MOISTURE LEVELS. THE
GREATER THE AMOUNT OF WIDESPREAD WETTING RAIN TODAY AND TONIGHT...
THE MORE LIKELY THAT RELATIVE HUMIDITY LEVELS WILL BE ABOVE RED
FLAG CRITERIA.
HOWEVER...EVEN IF RELATIVE HUMIDITY LEVELS ARE ABOVE RED FLAG
CRITERIA...THE EXPECTED TEMPERATURE AND WIND CONDITIONS COMBINED
WITH THE RECENT DRY CONDITIONS WILL ELEVATE THE FIRE DANGER...
ESPECIALLY FOR ANY AREAS THAT DO NOT RECEIVE MUCH WETTING RAINFALL
THIS EVENING AND TONIGHT AS FUEL MOISTURE WILL REMAIN QUITE LOW.
WHILE HIGH TEMPERATURES ARE EXPECTED TO REMAIN IN THE LOWER AND
MID 90S FOR TUESDAY AND WEDNESDAY...DEW POINTS ARE EXPECTED TO
SIGNIFICANTLY INCREASE...PREVENTING MINIMUM RELATIVE HUMIDITY
VALUES FROM DROPPING TO CRITICAL LEVELS.
ANOTHER COLD FRONT WILL MOVE INTO THE AREA THURSDAY...BRINGING
ANOTHER CHANCE OF SHOWERS AND THUNDERSTORMS. DAYTIME TEMPERATURES
WILL BE SOMEWHAT LOWER THURSDAY...AND SIGNIFICANTLY LOWER FRIDAY
WITH HIGHS IN THE UPPER 70S TO MID 80S.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 03Z...
* DURING THE EARLY OVERNIGHT PERIOD...THUNDERSTORMS AND GUSTY
WINDS. STRONGEST STORMS WITH LOW VSYBS AND STRONG WINDS EXPECTED
TO REMAIN SOUTH OF THE ORD/MDW TERMINALS.
* OVERNIGHT AFTER THE RAIN...POSSIBILITY OF SLIGHTLY REDUCED
VISIBILITIES.
LENNING
//DISCUSSION...UPDATED 00Z...
TSRA DEVELOPING IN THE VC OF I-80 SHOULD CONTINUE TO FILL IN ALONG
EAST-WEST LINE WITH THIS LINE LIKELY TO DRIFT SLOWLY NORTHWARD
TOWARD CHGO METRO TERMINALS THIS EVENING. ADDITIONAL NORTH-SOUTH
LINE OF TSRA OVER WESTERN ILLINOIS LIKELY TO CONTINUE EAST ACROSS
NORTHERN ILLINOIS AND LIKELY REACH TERMINALS JUST AFTER 0300Z AT
CHGO AND A BIT EARLIER AT RFD. IN THE WAKE OF THE TSRA LOOK FOR
WINDS TO VRB FOR A WHILE BEFORE LOCKING IN MORE W/NW LATE TONIGHT
INTO SUNDAY. CURRENT INDICATIONS ARE THAT WINDS SHOULD BE STRONG
ENOUGH SUNDAY TO PREVENT LAKE BREEZE FROM MAKING IT INTO ORD/MDW.
IZZI
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* MEDIUM TO HIGH CONFIDENCE IN REMAINING VFR EXCEPT PERHAPS FOR
BRIEF PERIODS.
* MEDIUM TO LOW CONFIDENCE IN POSSIBLE REDUCED VSBYS OVERNIGHT.
LENNING
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...VFR. SSW WINDS G35KT. VERY HOT/HIGH DENSITY ALTITUDE.
TUESDAY AND WEDNESDAY...VFR. VERY HOT/HIGH DENSITY ALTITUDE.
THURSDAY AND FRIDAY...CHC TSRA...OTHERWISE VFR.
IZZI
&&
.MARINE...
156 PM CDT
AN ACTIVE WEATHER PATTERN ACROSS THE NORTHERN UNITED STATES WILL
PRODUCE SEVERAL LOW PRESSURE SYSTEMS INTO NEXT WEEK...EACH OF THESE
LOWS ARE EXPECTED TO TRACK FROM THE PLAINS ACROSS THE UPPER
MISSISSIPPI VALLEY AND INTO ONTARIO. THESE SYSTEMS WILL PRODUCE
PERIODS OF STRONGER SOUTHERLY WINDS ACROSS THE LAKE. HOWEVER...THE MAIN
CONCERNS ACROSS THE LAKE WILL BE ON MONDAY AS A STRONG PRESSURE
GRADIENT SETS UP. THIS WILL LIKELY SUPPORT A PERIOD OF 30 KT
SOUTHERLY WINDS ON MONDAY INTO MONDAY NIGHT. THERE IS ALSO A
POTENTIAL FOR SOME GALE FORCE GUSTS...ESPECIALLY ACROSS THE
ILLINOIS AND INDIANA NEAR SHORES. STRONG GUSTS UP AROUND 35 KT ARE
POSSIBLE OVER THE LAND AREAS OF NORTHERN ILLINOIS...AND DUE TO
THE EXPECTED OFFSHORE COMPONENT TO THE FLOW...THESE WIND GUSTS
COULD EASILY AFFECT THE NEAR SHORE WATERS.
SOUTH TO SOUTHWESTERLY WINDS SHOULD CONTINUE AROUND 15 TO 25 KT
THROUGH THE MIDDLE OF NEXT WEEK AS WE REMAIN TO THE EAST OF LOW
PRESSURE ACROSS THE PLAINS AND UPPER MIDWEST.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 2 AM SUNDAY.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
947 PM CDT SAT JUN 16 2012
.MESOSCALE DISCUSSION...
947 PM CDT
HAVE CLEARED ABOUT THE NORTHERN HALF OF THE CWA FROM SEVERE
THUNDERSTORM WATCH. OBJECTIVE ANALYSIS AS WELL AS RADAR/SATELLITE
IMAGERY SUGGEST THAT SUFFICIENT CINH IS IN PLACE TO PREVENT SEVERE
THUNDERSTORM DEVELOPMENT NORTH OF I-80. HAVE OPTED TO LEAVE COOK
COUNTY IN THE WATCH SINCE SOME STRONGER CELLS IN NORTHWEST WILL
COUNTY WILL BE MOVING THROUGH IN THE NEXT 30-60 MINS. FARTHER
SOUTH OVER SOUTHERN PORTIONS OF THE CWA THE SEVERE THREAT ALSO
APPEARS TO BE DIMINISHING AS PREVIOUS STORMS AND OUTFLOW HAVE
LIKELY RESULTED IN MORE STABLE CONDITIONS. WILL HANG ON TO THE
SEVERE THUNDERSTORM WATCH FOR THESE AREAS THOUGH AS THERE IS STILL
SOME STRONG STORMS WITHIN THE LINE AND IT IS NOT OUT OF THE
QUESTION THAT THERE COULD BE SOME RE-INTENSIFICATION. IF CLOUD
TOPS CONTINUE TO COOL AND STORMS CONTINUE TO WEAKEN THEN THE
REMAINDER OF THE WATCH MAY BE ABLE TO BE CANCELLED EARLY.
IZZI
&&
.DISCUSSION...
330 PM CDT
A FEW AREAS OF CONCERN OVER THE COMING DAYS. THE FIRST WILL BE THE
POTENTIALLY SEVERE WEATHER THIS EVENING...FOLLOWED BY VERY HOT
WEATHER OPENING UP THE WORK WEEK. FOLLOWING THE SHOWERS AND
THUNDERSTORMS TONIGHT...THE NEXT CHANCE FOR PRECIPITATION WILL NOT
BE UNTIL LATER IN THE WEEK.
IN THE SHORT TERM...GOING THREAT FOR MORE OF AN EXPANDED
COVERAGE OF SHOWERS AND THUNDERSTORMS WILL BE ON THE INCREASE.
SYNOPTIC COLD FRONT WELL TO THE WEST AND ACROSS THE PLAINS AND
TIED TO A LOW LIFTING ACROSS CANADA IS SLOWLY SHIFTING TO THE
EAST. THIS FRONT WILL CONTINUE TO MOVE TOWARDS THE REGION
TONIGHT...BUT WEAKEN CONSIDERABLY BY THE TIME IT REACHES EASTERN
IOWA TONIGHT.
FOR THE IMMEDIATE AFTERNOON...SOUTHWESTERLY FLOW HAS ALLOWED A
RATHER LARGE SURGE OF MOISTURE TO BE TRANSPORTED ACROSS THE REGION.
OUTSIDE OF AREAS THAT SAW RAIN THIS MORNING...DEWPOINTS HAVE JUMPED
FROM AROUND 50 DEGREES TO THE MIDDLE AND UPPER 60S. FORECAST
SOUNDINGS NOT INDICATING MUCH DRY AIR TO IMPEDE THE CLIMB...AND
HAVE NUDGED DEWPOINTS UP ACROSS THE AREA. THE HIGHEST AXIS OF
INSTABILITY IS GENERALLY ANTICIPATED TO REMAIN SOUTH OF THE
AREA...AND CLOSER TO THE IOWA/ILLINOIS/MISSOURI JUNCTION...BUT
MUCAPE VALUES IN THE 1500 TO 2000 J/KG RANGE ARE STILL LIKELY
ACROSS THE EAST THIS AFTERNOON AND UP TO THE WI BORDER. OVERALL
SHEAR IS LOW...AND TIED CLOSER TO THE WAVE LIFTING ACROSS
WISCONSIN. GENERALLY EXPECTING THE SMALL...BUT EFFICIENT RAIN
PRODUCING SHOWERS AND THUNDER TO CONTINUE TO BUBBLE THIS AFTERNOON.
THE GREATEST CHANCES THROUGH AFTERNOON DO APPEAR TO BE EAST OF THE
I57 CORRIDOR...AND WEST OF I39.
THE PRIMARY FOCUS LATER THIS AFTERNOON AND INTO THE EVENING WILL BE
TIED TO A STRONG WAVE THAT IS SLIDING ACROSS THE MISSOURI AND IOWA
BORDER THIS AFTERNOON. PRESENTLY...SHOWER AND THUNDERSTORM CLUSTERS
ARE INCREASING IN OVERALL COVERAGE WITH AND AHEAD OF THIS FEATURE. THE
HIGHEST INSTABILITY AXIS IS WEST AND ACROSS THE MO/IA/IL BORDER
REGION...WITH RAP ANALYZED VALUES NEARING THE 3-4000 MARK. SHEAR
WILL INCREASE AS THE WAVE APPROACHES...AND THE CLUSTER OF STORMS
WILL INCREASE IN COVERAGE AS THEY SHIFT EAST...AND INTO A
SUPPORTIVE ENVIRONMENT. FORECAST SOUNDINGS AND MORNING RAOBS
SHOW A CONSIDERABLE INCREASE OF MOISTURE...WITH PWAT VALUES
JUMPING 2/3 TO 3/4 OF AN INCH ABOVE THEIR MORNING VALUES /AND
PEAKING AROUND THE 1.9 INCH RANGE. AS WAS SEEN EARLIER IN THE
DAY...IT DOES NOT TAKE MUCH FOR THESE STORMS TO PUT OUT A LOT OF
PRECIPITATION. THE LATEST HRRR HAS BEEN A DECENT PROXY FOR
COVERAGE AND TIMING...AND ANTICIPATE COVERAGE TO INCREASE FOR
ROCKFORD BEYOND THE 6P HOUR AND A FEW HOURS BEYOND FOR CHICAGO.
HEAVY RAIN IS THE BIGGEST THREAT WITH THESE STORMS...BUT SOME
POCKETS MAY CONTAIN SUB TO MARGINALLY SEVERE HAIL AND STRONG
WINDS ARE POSSIBLE...THOUGH DIURNALLY BY THE TIME THEY REACH THE
MAJORITY OF THE CWA...IT WILL BE GETTING INTO AN UNFAVORABLE TIME.
THE RAIN WILL BE WELCOME FOR MANY AREAS...BUT OVERALL DROUGHT
BUSTING ONES ARE NOT A LIKELIHOOD.
LONG TERM...THE JET ENGINE WILL TURN ON. THE COLD FRONT THAT IS
MARCHING EAST ACROSS THE MISSISSIPPI VALLEY TODAY WILL BASICALLY
WASH OUT AND ONLY DROP DEWPOINTS DOWN INTO THE LOWER 60S TO UPPER
50S...AND KEEP HIGH TEMPERATURES INTO THE 80S TOMORROW. BIG H8
THERMAL RIDGE WILL SLOWLY SHIFT EAST FROM THE PLAINS AND CLOSE TO
THE REGION...WARMING THE AREA BACK UP MONDAY. ENDED UP BUMPING UP HIGHS
FOR BOTH MONDAY AND TUESDAY TO BE INTO THE UPPER 90 RANGE /AND CAN
SEE A POSSIBLE 100 MARK SOMEWHERE ACROSS THE REGION/ IN THAT TIME.
NOT ONLY WILL IT BE HOT ON MONDAY...IT WILL BE INCREDIBLY WINDY.
FORECAST SOUNDINGS SHOW MIXED LAYER WINDS BREACHING THE 30KT
RANGE. THE POTENTIAL FOR CRITICAL FIRE WEATHER CONDITIONS WILL BE
ELEVATED...BUT SPECIFICS WILL BE FOLLOWED UP IN THE FIRE WEATHER
DISCUSSIONS THROUGH THE WEEKEND. THE 90S WILL CONTINUE THROUGH
WEDNESDAY...BEFORE A FRONT MOVES THROUGH THURSDAY AND COOLS OFF
THE AREA WITH THE NEXT CHANCE FOR SHOWERS AND STORMS.
SHEA
&&
.DISCUSSION...
330 PM CDT
A FEW AREAS OF CONCERN OVER THE COMING DAYS. THE FIRST WILL BE THE
POTENTIALLY SEVERE WEATHER THIS EVENING...FOLLOWED BY VERY HOT
WEATHER OPENING UP THE WORK WEEK. FOLLOWING THE SHOWERS AND
THUNDERSTORMS TONIGHT...THE NEXT CHANCE FOR PRECIPITATION WILL NOT
BE UNTIL LATER IN THE WEEK.
IN THE SHORT TERM...GOING THREAT FOR MORE OF AN EXPANDED
COVERAGE OF SHOWERS AND THUNDERSTORMS WILL BE ON THE INCREASE.
SYNOPTIC COLD FRONT WELL TO THE WEST AND ACROSS THE PLAINS AND
TIED TO A LOW LIFTING ACROSS CANADA IS SLOWLY SHIFTING TO THE
EAST. THIS FRONT WILL CONTINUE TO MOVE TOWARDS THE REGION
TONIGHT...BUT WEAKEN CONSIDERABLY BY THE TIME IT REACHES EASTERN
IOWA TONIGHT.
FOR THE IMMEDIATE AFTERNOON...SOUTHWESTERLY FLOW HAS ALLOWED A
RATHER LARGE SURGE OF MOISTURE TO BE TRANSPORTED ACROSS THE REGION.
OUTSIDE OF AREAS THAT SAW RAIN THIS MORNING...DEWPOINTS HAVE JUMPED
FROM AROUND 50 DEGREES TO THE MIDDLE AND UPPER 60S. FORECAST
SOUNDINGS NOT INDICATING MUCH DRY AIR TO IMPEDE THE CLIMB...AND
HAVE NUDGED DEWPOINTS UP ACROSS THE AREA. THE HIGHEST AXIS OF
INSTABILITY IS GENERALLY ANTICIPATED TO REMAIN SOUTH OF THE
AREA...AND CLOSER TO THE IOWA/ILLINOIS/MISSOURI JUNCTION...BUT
MUCAPE VALUES IN THE 1500 TO 2000 J/KG RANGE ARE STILL LIKELY
ACROSS THE EAST THIS AFTERNOON AND UP TO THE WI BORDER. OVERALL
SHEAR IS LOW...AND TIED CLOSER TO THE WAVE LIFTING ACROSS
WISCONSIN. GENERALLY EXPECTING THE SMALL...BUT EFFICIENT RAIN
PRODUCING SHOWERS AND THUNDER TO CONTINUE TO BUBBLE THIS AFTERNOON.
THE GREATEST CHANCES THROUGH AFTERNOON DO APPEAR TO BE EAST OF THE
I57 CORRIDOR...AND WEST OF I39.
THE PRIMARY FOCUS LATER THIS AFTERNOON AND INTO THE EVENING WILL BE
TIED TO A STRONG WAVE THAT IS SLIDING ACROSS THE MISSOURI AND IOWA
BORDER THIS AFTERNOON. PRESENTLY...SHOWER AND THUNDERSTORM CLUSTERS
ARE INCREASING IN OVERALL COVERAGE WITH AND AHEAD OF THIS FEATURE. THE
HIGHEST INSTABILITY AXIS IS WEST AND ACROSS THE MO/IA/IL BORDER
REGION...WITH RAP ANALYZED VALUES NEARING THE 3-4000 MARK. SHEAR
WILL INCREASE AS THE WAVE APPROACHES...AND THE CLUSTER OF STORMS
WILL INCREASE IN COVERAGE AS THEY SHIFT EAST...AND INTO A
SUPPORTIVE ENVIRONMENT. FORECAST SOUNDINGS AND MORNING RAOBS
SHOW A CONSIDERABLE INCREASE OF MOISTURE...WITH PWAT VALUES
JUMPING 2/3 TO 3/4 OF AN INCH ABOVE THEIR MORNING VALUES /AND
PEAKING AROUND THE 1.9 INCH RANGE. AS WAS SEEN EARLIER IN THE
DAY...IT DOES NOT TAKE MUCH FOR THESE STORMS TO PUT OUT A LOT OF
PRECIPITATION. THE LATEST HRRR HAS BEEN A DECENT PROXY FOR
COVERAGE AND TIMING...AND ANTICIPATE COVERAGE TO INCREASE FOR
ROCKFORD BEYOND THE 6P HOUR AND A FEW HOURS BEYOND FOR CHICAGO.
HEAVY RAIN IS THE BIGGEST THREAT WITH THESE STORMS...BUT SOME
POCKETS MAY CONTAIN SUB TO MARGINALLY SEVERE HAIL AND STRONG
WINDS ARE POSSIBLE...THOUGH DIURNALLY BY THE TIME THEY REACH THE
MAJORITY OF THE CWA...IT WILL BE GETTING INTO AN UNFAVORABLE TIME.
THE RAIN WILL BE WELCOME FOR MANY AREAS...BUT OVERALL DROUGHT
BUSTING ONES ARE NOT A LIKELIHOOD.
LONG TERM...THE JET ENGINE WILL TURN ON. THE COLD FRONT THAT IS
MARCHING EAST ACROSS THE MISSISSIPPI VALLEY TODAY WILL BASICALLY
WASH OUT AND ONLY DROP DEWPOINTS DOWN INTO THE LOWER 60S TO UPPER
50S...AND KEEP HIGH TEMPERATURES INTO THE 80S TOMORROW. BIG H8
THERMAL RIDGE WILL SLOWLY SHIFT EAST FROM THE PLAINS AND CLOSE TO
THE REGION...WARMING THE AREA BACK UP MONDAY. ENDED UP BUMPING UP HIGHS
FOR BOTH MONDAY AND TUESDAY TO BE INTO THE UPPER 90 RANGE /AND CAN
SEE A POSSIBLE 100 MARK SOMEWHERE ACROSS THE REGION/ IN THAT TIME.
NOT ONLY WILL IT BE HOT ON MONDAY...IT WILL BE INCREDIBLY WINDY.
FORECAST SOUNDINGS SHOW MIXED LAYER WINDS BREACHING THE 30KT
RANGE. THE POTENTIAL FOR CRITICAL FIRE WEATHER CONDITIONS WILL BE
ELEVATED...BUT SPECIFICS WILL BE FOLLOWED UP IN THE FIRE WEATHER
DISCUSSIONS THROUGH THE WEEKEND. THE 90S WILL CONTINUE THROUGH
WEDNESDAY...BEFORE A FRONT MOVES THROUGH THURSDAY AND COOLS OFF
THE AREA WITH THE NEXT CHANCE FOR SHOWERS AND STORMS.
SHEA
&&
.FIRE WEATHER...
515 PM CDT
HOT AND WINDY CONDITIONS MAY RESULT IN CRITICAL AND DANGEROUS
FIRE WEATHER CONDITIONS ON MONDAY.
FOR THE REMAINDER OF THIS AFTERNOON AND THIS EVENING...INCREASING
DEWPOINTS ACROSS THE AREA WILL LIMIT MINIMUM RELATIVE HUMIDITY
VALUES TO 35 TO 40 PERCENT AS TEMPERATURES TOP OUT IN THE LOWER
90S. WINDS WILL OUT OF THE SOUTHWEST AT 10 TO 15 MPH...GUSTING
TO AROUND 20 MPH.
SCATTERED SHOWERS AND THUNDERSTORMS WILL BRING WETTING RAIN TO
SOME LOCATIONS THROUGH EARLY THIS EVENING. THERE IS THE POTENTIAL
FOR ADDITIONAL THUNDERSTORMS THROUGH LATE THIS EVENING WHICH MAY
BRING SOME ADDITIONAL WETTING RAIN...AND SOME THUNDERSTORMS MAY
EVEN BRING SOME LOCALLY HEAVY RAINFALL.
WHILE RED FLAG CRITERIA WILL NOT BE REACHED TODAY...THE RECENT
VERY DRY CONDITIONS COMBINED WITH HIGH TEMPERATURES...MODESTLY
LOW DEW POINTS AND MODERATELY STRONG WINDS WILL RESULT IN ELEVATED
WILDFIRE DANGER.
A WEAK...COLD FRONT WILL MOVE INTO THE AREA TONIGHT AND EARLY
SUNDAY MORNING...BRINGING SLIGHTLY COOLER AIR...WITH HIGHS IN THE
MID AND UPPER 80S.
MUCH WARMER AIR WILL RETURN MONDAY WITH SOUTHWEST WINDS GUSTING AS
HIGH AS 40 MPH. SOME QUESTION REMAINS AS TO HOW LOW DEWPOINTS MAY
MAY DROP MONDAY AFTERNOON IF DRIER AIR ALOFT MIXES DOWN TO THE
SURFACE. CURRENTLY...EXPECT THAT HIGH TEMPERATURES WILL BE IN THE
MIDDLE 90S. EVEN DEWPOINTS IN THE LOWER 60S WILL CAUSE RELATIVE
HUMIDITY VALUES TO DROP CLOSE TO 30 PERCENT OVER MUCH OF THE AREA
AND DEWPOINTS IN THE UPPER 50S WILL BRING RELATIVE HUMIDITY LEVELS
IN RED FLAG CRITERIA RANGE.
ANOTHER WILD CARD IS HOW RAINFALL OCCURRING THIS AFTERNOON AND HOW
MUCH ADDITIONAL RAINFALL THAT MAY OCCUR LATER THIS EVENING WILL
AFFECT FUEL MOISTURE LEVELS AS WELL AS SOIL MOISTURE LEVELS. THE
GREATER THE AMOUNT OF WIDESPREAD WETTING RAIN TODAY AND TONIGHT...
THE MORE LIKELY THAT RELATIVE HUMIDITY LEVELS WILL BE ABOVE RED
FLAG CRITERIA.
HOWEVER...EVEN IF RELATIVE HUMIDITY LEVELS ARE ABOVE RED FLAG
CRITERIA...THE EXPECTED TEMPERATURE AND WIND CONDITIONS COMBINED
WITH THE RECENT DRY CONDITIONS WILL ELEVATE THE FIRE DANGER...
ESPECIALLY FOR ANY AREAS THAT DO NOT RECEIVE MUCH WETTING RAINFALL
THIS EVENING AND TONIGHT AS FUEL MOISTURE WILL REMAIN QUITE LOW.
WHILE HIGH TEMPERATURES ARE EXPECTED TO REMAIN IN THE LOWER AND
MID 90S FOR TUESDAY AND WEDNESDAY...DEW POINTS ARE EXPECTED TO
SIGNIFICANTLY INCREASE...PREVENTING MINIMUM RELATIVE HUMIDITY
VALUES FROM DROPPING TO CRITICAL LEVELS.
ANOTHER COLD FRONT WILL MOVE INTO THE AREA THURSDAY...BRINGING
ANOTHER CHANCE OF SHOWERS AND THUNDERSTORMS. DAYTIME TEMPERATURES
WILL BE SOMEWHAT LOWER THURSDAY...AND SIGNIFICANTLY LOWER FRIDAY
WITH HIGHS IN THE UPPER 70S TO MID 80S.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* TSRA THIS EVENING
IZZI
//DISCUSSION...UPDATED 00Z...
TSRA DEVELOPING IN THE VC OF I-80 SHOULD CONTINUE TO FILL IN ALONG
EAST-WEST LINE WITH THIS LINE LIKELY TO DRIFT SLOWLY NORTHWARD
TOWARD CHGO METRO TERMINALS THIS EVENING. ADDITIONAL NORTH-SOUTH
LINE OF TSRA OVER WESTERN ILLINOIS LIKELY TO CONTINUE EAST ACROSS
NORTHERN ILLINOIS AND LIKELY REACH TERMINALS JUST AFTER 0300Z AT
CHGO AND A BIT EARLIER AT RFD. IN THE WAKE OF THE TSRA LOOK FOR
WINDS TO VRB FOR A WHILE BEFORE LOCKING IN MORE W/NW LATE TONIGHT
INTO SUNDAY. CURRENT INDICATIONS ARE THAT WINDS SHOULD BE STRONG
ENOUGH SUNDAY TO PREVENT LAKE BREEZE FROM MAKING IT INTO ORD/MDW.
IZZI
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* MEDIUM CONFIDENCE ON TSRA TIMING/INTENSITY THIS EVENING
* HIGH CONFIDENCE ALL OTHER ELEMENTS
IZZI
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...VFR. SSW WINDS G35KT. VERY HOT/HIGH DENSITY ALTITUDE.
TUESDAY AND WEDNESDAY...VFR. VERY HOT/HIGH DENSITY ALTITUDE.
THURSDAY AND FRIDAY...CHC TSRA...OTHERWISE VFR.
IZZI
&&
.MARINE...
156 PM CDT
AN ACTIVE WEATHER PATTERN ACROSS THE NORTHERN UNITED STATES WILL
PRODUCE SEVERAL LOW PRESSURE SYSTEMS INTO NEXT WEEK...EACH OF THESE
LOWS ARE EXPECTED TO TRACK FROM THE PLAINS ACROSS THE UPPER
MISSISSIPPI VALLEY AND INTO ONTARIO. THESE SYSTEMS WILL PRODUCE
PERIODS OF STRONGER SOUTHERLY WINDS ACROSS THE LAKE. HOWEVER...THE MAIN
CONCERNS ACROSS THE LAKE WILL BE ON MONDAY AS A STRONG PRESSURE
GRADIENT SETS UP. THIS WILL LIKELY SUPPORT A PERIOD OF 30 KT
SOUTHERLY WINDS ON MONDAY INTO MONDAY NIGHT. THERE IS ALSO A
POTENTIAL FOR SOME GALE FORCE GUSTS...ESPECIALLY ACROSS THE
ILLINOIS AND INDIANA NEAR SHORES. STRONG GUSTS UP AROUND 35 KT ARE
POSSIBLE OVER THE LAND AREAS OF NORTHERN ILLINOIS...AND DUE TO
THE EXPECTED OFFSHORE COMPONENT TO THE FLOW...THESE WIND GUSTS
COULD EASILY AFFECT THE NEAR SHORE WATERS.
SOUTH TO SOUTHWESTERLY WINDS SHOULD CONTINUE AROUND 15 TO 25 KT
THROUGH THE MIDDLE OF NEXT WEEK AS WE REMAIN TO THE EAST OF LOW
PRESSURE ACROSS THE PLAINS AND UPPER MIDWEST.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 10 PM SATURDAY.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
702 PM CDT SAT JUN 16 2012
.MESOSCALE DISCUSSION...
700 PM CDT
CLUSTER ACROSS THE IA/MO/IL CORRIDOR CONTINUES TO INTENSIFY AS IT
MOVES INTO AN UNSTABLE AIRMASS...AND THAT WILL CONTINUE TO BE THE
FOCUS AS PREVIOUSLY THOUGHT. CLUSTER CONTINUES TO CONGEAL AND FORM
A BOWING SEGMENT. THOUGH CONDITIONS HAVE DECREASED OVER THE LAST
20-30 MINUTES ALONG THE LEADING EDGE...IT MAY BE TEMPORARY AS THE
ATMOSPHERE REMAINS UNSTABLE AHEAD OF THE COMPLEX. WITH THE CONCERN
OF THE SEVERE POTENTIAL...COORDINATED WITH SPC AND ISSUED A WATCH
COVERING THE CWA. THE NEXT AND LATEST THREAT COVERS WHAT LOOKS
LIKE A WARM ADVECTION STYLE WING OF SHOWERS AND THUNDERSTORMS THAT
HAVE FORMED ALONG A CONFLUENT WIND AXIS SOUTH OF I-80. HIGH PWATS
WILL LEAD TO HEAVY RAINFALL...AND UPWIND PROPAGATION VECTORS ARE
LESS THAN 10 KT ... IN SORT OF A CORFIDI VECTOR RIDGE ACROSS THAT
GENERAL AREA AND SOME MERGING AND TRAINING MAY CONTINUE WITH THESE
STORMS. WHILE THE REGION REMAINS IN DROUGHT...AND THE RAIN IS
NEEDED...RATES ARE EXPECTED TO BE HIGHER THAN WHAT THE GROUND CAN
HANDLE AT ONCE...AND THAT COULD LEAD TO LOCALIZED FLOODING WITH
1-2 INCH AN HOUR RAINFALL RATES EXPECTED. ONE CONCERN WITH ONGOING
CONVECTION ACROSS THE I-80 CORRIDOR IS HOW THAT WILL IMPACT THE
ATMOSPHERE...AND WHETHER IT WILL COOL AND MODIFY THE ATMOSPHERE
THAT THE MCS WILL ENCOUNTER. WILL NEED TO CONTINUE TO KEEP AN EYE
ON THE LATEST TRENDS.
SHEA
.PREVIOUS MESOSCALE DISCUSSION...
458 PM CDT
TWO MAIN FOCUS AREAS THIS AFTERNOON FOR STORMS. STORMS ACROSS
INDIANA ARE HELPING TO OCCASIONALLY HIT SEVERE CRITERIA ON THE NOSE
OF RAP/RUC ANALYZED H7 SPEED MAX AND NOSE OF A THETA E TONGUE. AT
THE SURFACE...DESTABILIZATION HAS ALREADY TAKEN PLACE. DEWPOINTS
IN THE MIDDLE AND UPPER 60S SUPPORT SURFACE BASED CAPE OF
1000-1500 J/KG AVAILABLE TO BE REALIZED. A FEW OF THE STORMS HAVE
BEEN ABLE TO REACH SEVERE CRITERIA...ALLOWING GOLF BALL SIZED HAIL
TO FALL. THIS AREA WILL CONTINUE TO SHIFT EAST THROUGH THE EARLY
EVENING HOURS.
THE SECOND FOCUS IS TIED TO THE MCV/SHORTWAVE MOVING ACROSS
SOUTHERN IOWA AND SHIFTING EAST. MAIN INSTABILITY AXIS SEEMS TO BE
LINED UP DIRECTLY TO THE EAST OF THIS FEATURE AND ACROSS CENTRAL
ILLINOIS. WITHIN THIS CORRIDOR CAPE VALUES OF UP TO 3000 J/KG ARE
PRESENT WITHIN AND THE ATMOSPHERE IS BASICALLY UNTAPPED. CLOUD
TOPS CONTINUE TO RAPIDLY COOL WITH THESE STORMS AND THE FORMATION
OF A COLD POOL MAY BE UNDERWAY. THE EARLIER RAP/RUC HAD BEEN
UNDER DOING LOWER LEVEL WINDS WHEN COMPARED TO PROFILER AND 88D VAD
PROFILES...BUT THE LATEST RUNS SEEM TO HAVE A GOOD HANDLE ON THE
CURRENT SITUATION. ALL GUIDANCE INCREASES THE LOWER LEVEL WINDS
EARLY THIS EVENING AND THIS MAY HELP TO CONVECTION TO FORM INTO A
BOWING SEGMENT AIDED BY A MODERATE REAR INFLOW JET. THERE IS NO
REASON FOR THE ACTIVITY WILL WANE BEFORE IT MOVES EAST AND INTO THE
CWA THIS EVENING...BUT WILL BE MORE OF A WAIT AND SEE TO TELL IF
ANY ORGANIZATION WITH THE COLD POOL INCREASES...OF IF THE STORMS
REMAIN MORE OF THE MULTICELLULAR CLUSTER THAT IS PRESENTLY BEING
NOTED. INCREDIBLY HIGH PWATS /RANGING FROM 1.7 TO ROUGHLY 1.9
INCHES/ WILL ALSO SUPPORT THE TORRENTIAL RAINFALL AND LOCALIZED
FLOODING THREAT. SHEA
.DISCUSSION...
330 PM CDT
A FEW AREAS OF CONCERN OVER THE COMING DAYS. THE FIRST WILL BE THE
POTENTIALLY SEVERE WEATHER THIS EVENING...FOLLOWED BY VERY HOT
WEATHER OPENING UP THE WORK WEEK. FOLLOWING THE SHOWERS AND
THUNDERSTORMS TONIGHT...THE NEXT CHANCE FOR PRECIPITATION WILL NOT
BE UNTIL LATER IN THE WEEK.
IN THE SHORT TERM...GOING THREAT FOR MORE OF AN EXPANDED
COVERAGE OF SHOWERS AND THUNDERSTORMS WILL BE ON THE INCREASE.
SYNOPTIC COLD FRONT WELL TO THE WEST AND ACROSS THE PLAINS AND
TIED TO A LOW LIFTING ACROSS CANADA IS SLOWLY SHIFTING TO THE
EAST. THIS FRONT WILL CONTINUE TO MOVE TOWARDS THE REGION
TONIGHT...BUT WEAKEN CONSIDERABLY BY THE TIME IT REACHES EASTERN
IOWA TONIGHT.
FOR THE IMMEDIATE AFTERNOON...SOUTHWESTERLY FLOW HAS ALLOWED A
RATHER LARGE SURGE OF MOISTURE TO BE TRANSPORTED ACROSS THE REGION.
OUTSIDE OF AREAS THAT SAW RAIN THIS MORNING...DEWPOINTS HAVE JUMPED
FROM AROUND 50 DEGREES TO THE MIDDLE AND UPPER 60S. FORECAST
SOUNDINGS NOT INDICATING MUCH DRY AIR TO IMPEDE THE CLIMB...AND
HAVE NUDGED DEWPOINTS UP ACROSS THE AREA. THE HIGHEST AXIS OF
INSTABILITY IS GENERALLY ANTICIPATED TO REMAIN SOUTH OF THE
AREA...AND CLOSER TO THE IOWA/ILLINOIS/MISSOURI JUNCTION...BUT
MUCAPE VALUES IN THE 1500 TO 2000 J/KG RANGE ARE STILL LIKELY
ACROSS THE EAST THIS AFTERNOON AND UP TO THE WI BORDER. OVERALL
SHEAR IS LOW...AND TIED CLOSER TO THE WAVE LIFTING ACROSS
WISCONSIN. GENERALLY EXPECTING THE SMALL...BUT EFFICIENT RAIN
PRODUCING SHOWERS AND THUNDER TO CONTINUE TO BUBBLE THIS AFTERNOON.
THE GREATEST CHANCES THROUGH AFTERNOON DO APPEAR TO BE EAST OF THE
I57 CORRIDOR...AND WEST OF I39.
THE PRIMARY FOCUS LATER THIS AFTERNOON AND INTO THE EVENING WILL BE
TIED TO A STRONG WAVE THAT IS SLIDING ACROSS THE MISSOURI AND IOWA
BORDER THIS AFTERNOON. PRESENTLY...SHOWER AND THUNDERSTORM CLUSTERS
ARE INCREASING IN OVERALL COVERAGE WITH AND AHEAD OF THIS FEATURE. THE
HIGHEST INSTABILITY AXIS IS WEST AND ACROSS THE MO/IA/IL BORDER
REGION...WITH RAP ANALYZED VALUES NEARING THE 3-4000 MARK. SHEAR
WILL INCREASE AS THE WAVE APPROACHES...AND THE CLUSTER OF STORMS
WILL INCREASE IN COVERAGE AS THEY SHIFT EAST...AND INTO A
SUPPORTIVE ENVIRONMENT. FORECAST SOUNDINGS AND MORNING RAOBS
SHOW A CONSIDERABLE INCREASE OF MOISTURE...WITH PWAT VALUES
JUMPING 2/3 TO 3/4 OF AN INCH ABOVE THEIR MORNING VALUES /AND
PEAKING AROUND THE 1.9 INCH RANGE. AS WAS SEEN EARLIER IN THE
DAY...IT DOES NOT TAKE MUCH FOR THESE STORMS TO PUT OUT A LOT OF
PRECIPITATION. THE LATEST HRRR HAS BEEN A DECENT PROXY FOR
COVERAGE AND TIMING...AND ANTICIPATE COVERAGE TO INCREASE FOR
ROCKFORD BEYOND THE 6P HOUR AND A FEW HOURS BEYOND FOR CHICAGO.
HEAVY RAIN IS THE BIGGEST THREAT WITH THESE STORMS...BUT SOME
POCKETS MAY CONTAIN SUB TO MARGINALLY SEVERE HAIL AND STRONG
WINDS ARE POSSIBLE...THOUGH DIURNALLY BY THE TIME THEY REACH THE
MAJORITY OF THE CWA...IT WILL BE GETTING INTO AN UNFAVORABLE TIME.
THE RAIN WILL BE WELCOME FOR MANY AREAS...BUT OVERALL DROUGHT
BUSTING ONES ARE NOT A LIKELIHOOD.
LONG TERM...THE JET ENGINE WILL TURN ON. THE COLD FRONT THAT IS
MARCHING EAST ACROSS THE MISSISSIPPI VALLEY TODAY WILL BASICALLY
WASH OUT AND ONLY DROP DEWPOINTS DOWN INTO THE LOWER 60S TO UPPER
50S...AND KEEP HIGH TEMPERATURES INTO THE 80S TOMORROW. BIG H8
THERMAL RIDGE WILL SLOWLY SHIFT EAST FROM THE PLAINS AND CLOSE TO
THE REGION...WARMING THE AREA BACK UP MONDAY. ENDED UP BUMPING UP HIGHS
FOR BOTH MONDAY AND TUESDAY TO BE INTO THE UPPER 90 RANGE /AND CAN
SEE A POSSIBLE 100 MARK SOMEWHERE ACROSS THE REGION/ IN THAT TIME.
NOT ONLY WILL IT BE HOT ON MONDAY...IT WILL BE INCREDIBLY WINDY.
FORECAST SOUNDINGS SHOW MIXED LAYER WINDS BREACHING THE 30KT
RANGE. THE POTENTIAL FOR CRITICAL FIRE WEATHER CONDITIONS WILL BE
ELEVATED...BUT SPECIFICS WILL BE FOLLOWED UP IN THE FIRE WEATHER
DISCUSSIONS THROUGH THE WEEKEND. THE 90S WILL CONTINUE THROUGH
WEDNESDAY...BEFORE A FRONT MOVES THROUGH THURSDAY AND COOLS OFF
THE AREA WITH THE NEXT CHANCE FOR SHOWERS AND STORMS.
SHEA
&&
.DISCUSSION...
330 PM CDT
A FEW AREAS OF CONCERN OVER THE COMING DAYS. THE FIRST WILL BE THE
POTENTIALLY SEVERE WEATHER THIS EVENING...FOLLOWED BY VERY HOT
WEATHER OPENING UP THE WORK WEEK. FOLLOWING THE SHOWERS AND
THUNDERSTORMS TONIGHT...THE NEXT CHANCE FOR PRECIPITATION WILL NOT
BE UNTIL LATER IN THE WEEK.
IN THE SHORT TERM...GOING THREAT FOR MORE OF AN EXPANDED
COVERAGE OF SHOWERS AND THUNDERSTORMS WILL BE ON THE INCREASE.
SYNOPTIC COLD FRONT WELL TO THE WEST AND ACROSS THE PLAINS AND
TIED TO A LOW LIFTING ACROSS CANADA IS SLOWLY SHIFTING TO THE
EAST. THIS FRONT WILL CONTINUE TO MOVE TOWARDS THE REGION
TONIGHT...BUT WEAKEN CONSIDERABLY BY THE TIME IT REACHES EASTERN
IOWA TONIGHT.
FOR THE IMMEDIATE AFTERNOON...SOUTHWESTERLY FLOW HAS ALLOWED A
RATHER LARGE SURGE OF MOISTURE TO BE TRANSPORTED ACROSS THE REGION.
OUTSIDE OF AREAS THAT SAW RAIN THIS MORNING...DEWPOINTS HAVE JUMPED
FROM AROUND 50 DEGREES TO THE MIDDLE AND UPPER 60S. FORECAST
SOUNDINGS NOT INDICATING MUCH DRY AIR TO IMPEDE THE CLIMB...AND
HAVE NUDGED DEWPOINTS UP ACROSS THE AREA. THE HIGHEST AXIS OF
INSTABILITY IS GENERALLY ANTICIPATED TO REMAIN SOUTH OF THE
AREA...AND CLOSER TO THE IOWA/ILLINOIS/MISSOURI JUNCTION...BUT
MUCAPE VALUES IN THE 1500 TO 2000 J/KG RANGE ARE STILL LIKELY
ACROSS THE EAST THIS AFTERNOON AND UP TO THE WI BORDER. OVERALL
SHEAR IS LOW...AND TIED CLOSER TO THE WAVE LIFTING ACROSS
WISCONSIN. GENERALLY EXPECTING THE SMALL...BUT EFFICIENT RAIN
PRODUCING SHOWERS AND THUNDER TO CONTINUE TO BUBBLE THIS AFTERNOON.
THE GREATEST CHANCES THROUGH AFTERNOON DO APPEAR TO BE EAST OF THE
I57 CORRIDOR...AND WEST OF I39.
THE PRIMARY FOCUS LATER THIS AFTERNOON AND INTO THE EVENING WILL BE
TIED TO A STRONG WAVE THAT IS SLIDING ACROSS THE MISSOURI AND IOWA
BORDER THIS AFTERNOON. PRESENTLY...SHOWER AND THUNDERSTORM CLUSTERS
ARE INCREASING IN OVERALL COVERAGE WITH AND AHEAD OF THIS FEATURE. THE
HIGHEST INSTABILITY AXIS IS WEST AND ACROSS THE MO/IA/IL BORDER
REGION...WITH RAP ANALYZED VALUES NEARING THE 3-4000 MARK. SHEAR
WILL INCREASE AS THE WAVE APPROACHES...AND THE CLUSTER OF STORMS
WILL INCREASE IN COVERAGE AS THEY SHIFT EAST...AND INTO A
SUPPORTIVE ENVIRONMENT. FORECAST SOUNDINGS AND MORNING RAOBS
SHOW A CONSIDERABLE INCREASE OF MOISTURE...WITH PWAT VALUES
JUMPING 2/3 TO 3/4 OF AN INCH ABOVE THEIR MORNING VALUES /AND
PEAKING AROUND THE 1.9 INCH RANGE. AS WAS SEEN EARLIER IN THE
DAY...IT DOES NOT TAKE MUCH FOR THESE STORMS TO PUT OUT A LOT OF
PRECIPITATION. THE LATEST HRRR HAS BEEN A DECENT PROXY FOR
COVERAGE AND TIMING...AND ANTICIPATE COVERAGE TO INCREASE FOR
ROCKFORD BEYOND THE 6P HOUR AND A FEW HOURS BEYOND FOR CHICAGO.
HEAVY RAIN IS THE BIGGEST THREAT WITH THESE STORMS...BUT SOME
POCKETS MAY CONTAIN SUB TO MARGINALLY SEVERE HAIL AND STRONG
WINDS ARE POSSIBLE...THOUGH DIURNALLY BY THE TIME THEY REACH THE
MAJORITY OF THE CWA...IT WILL BE GETTING INTO AN UNFAVORABLE TIME.
THE RAIN WILL BE WELCOME FOR MANY AREAS...BUT OVERALL DROUGHT
BUSTING ONES ARE NOT A LIKELIHOOD.
LONG TERM...THE JET ENGINE WILL TURN ON. THE COLD FRONT THAT IS
MARCHING EAST ACROSS THE MISSISSIPPI VALLEY TODAY WILL BASICALLY
WASH OUT AND ONLY DROP DEWPOINTS DOWN INTO THE LOWER 60S TO UPPER
50S...AND KEEP HIGH TEMPERATURES INTO THE 80S TOMORROW. BIG H8
THERMAL RIDGE WILL SLOWLY SHIFT EAST FROM THE PLAINS AND CLOSE TO
THE REGION...WARMING THE AREA BACK UP MONDAY. ENDED UP BUMPING UP HIGHS
FOR BOTH MONDAY AND TUESDAY TO BE INTO THE UPPER 90 RANGE /AND CAN
SEE A POSSIBLE 100 MARK SOMEWHERE ACROSS THE REGION/ IN THAT TIME.
NOT ONLY WILL IT BE HOT ON MONDAY...IT WILL BE INCREDIBLY WINDY.
FORECAST SOUNDINGS SHOW MIXED LAYER WINDS BREACHING THE 30KT
RANGE. THE POTENTIAL FOR CRITICAL FIRE WEATHER CONDITIONS WILL BE
ELEVATED...BUT SPECIFICS WILL BE FOLLOWED UP IN THE FIRE WEATHER
DISCUSSIONS THROUGH THE WEEKEND. THE 90S WILL CONTINUE THROUGH
WEDNESDAY...BEFORE A FRONT MOVES THROUGH THURSDAY AND COOLS OFF
THE AREA WITH THE NEXT CHANCE FOR SHOWERS AND STORMS.
SHEA
&&
.FIRE WEATHER...
515 PM CDT
HOT AND WINDY CONDITIONS MAY RESULT IN CRITICAL AND DANGEROUS
FIRE WEATHER CONDITIONS ON MONDAY.
FOR THE REMAINDER OF THIS AFTERNOON AND THIS EVENING...INCREASING
DEWPOINTS ACROSS THE AREA WILL LIMIT MINIMUM RELATIVE HUMIDITY
VALUES TO 35 TO 40 PERCENT AS TEMPERATURES TOP OUT IN THE LOWER
90S. WINDS WILL OUT OF THE SOUTHWEST AT 10 TO 15 MPH...GUSTING
TO AROUND 20 MPH.
SCATTERED SHOWERS AND THUNDERSTORMS WILL BRING WETTING RAIN TO
SOME LOCATIONS THROUGH EARLY THIS EVENING. THERE IS THE POTENTIAL
FOR ADDITIONAL THUNDERSTORMS THROUGH LATE THIS EVENING WHICH MAY
BRING SOME ADDITIONAL WETTING RAIN...AND SOME THUNDERSTORMS MAY
EVEN BRING SOME LOCALLY HEAVY RAINFALL.
WHILE RED FLAG CRITERIA WILL NOT BE REACHED TODAY...THE RECENT
VERY DRY CONDITIONS COMBINED WITH HIGH TEMPERATURES...MODESTLY
LOW DEW POINTS AND MODERATELY STRONG WINDS WILL RESULT IN ELEVATED
WILDFIRE DANGER.
A WEAK...COLD FRONT WILL MOVE INTO THE AREA TONIGHT AND EARLY
SUNDAY MORNING...BRINGING SLIGHTLY COOLER AIR...WITH HIGHS IN THE
MID AND UPPER 80S.
MUCH WARMER AIR WILL RETURN MONDAY WITH SOUTHWEST WINDS GUSTING AS
HIGH AS 40 MPH. SOME QUESTION REMAINS AS TO HOW LOW DEWPOINTS MAY
MAY DROP MONDAY AFTERNOON IF DRIER AIR ALOFT MIXES DOWN TO THE
SURFACE. CURRENTLY...EXPECT THAT HIGH TEMPERATURES WILL BE IN THE
MIDDLE 90S. EVEN DEWPOINTS IN THE LOWER 60S WILL CAUSE RELATIVE
HUMIDITY VALUES TO DROP CLOSE TO 30 PERCENT OVER MUCH OF THE AREA
AND DEWPOINTS IN THE UPPER 50S WILL BRING RELATIVE HUMIDITY LEVELS
IN RED FLAG CRITERIA RANGE.
ANOTHER WILD CARD IS HOW RAINFALL OCCURRING THIS AFTERNOON AND HOW
MUCH ADDITIONAL RAINFALL THAT MAY OCCUR LATER THIS EVENING WILL
AFFECT FUEL MOISTURE LEVELS AS WELL AS SOIL MOISTURE LEVELS. THE
GREATER THE AMOUNT OF WIDESPREAD WETTING RAIN TODAY AND TONIGHT...
THE MORE LIKELY THAT RELATIVE HUMIDITY LEVELS WILL BE ABOVE RED
FLAG CRITERIA.
HOWEVER...EVEN IF RELATIVE HUMIDITY LEVELS ARE ABOVE RED FLAG
CRITERIA...THE EXPECTED TEMPERATURE AND WIND CONDITIONS COMBINED
WITH THE RECENT DRY CONDITIONS WILL ELEVATE THE FIRE DANGER...
ESPECIALLY FOR ANY AREAS THAT DO NOT RECEIVE MUCH WETTING RAINFALL
THIS EVENING AND TONIGHT AS FUEL MOISTURE WILL REMAIN QUITE LOW.
WHILE HIGH TEMPERATURES ARE EXPECTED TO REMAIN IN THE LOWER AND
MID 90S FOR TUESDAY AND WEDNESDAY...DEW POINTS ARE EXPECTED TO
SIGNIFICANTLY INCREASE...PREVENTING MINIMUM RELATIVE HUMIDITY
VALUES FROM DROPPING TO CRITICAL LEVELS.
ANOTHER COLD FRONT WILL MOVE INTO THE AREA THURSDAY...BRINGING
ANOTHER CHANCE OF SHOWERS AND THUNDERSTORMS. DAYTIME TEMPERATURES
WILL BE SOMEWHAT LOWER THURSDAY...AND SIGNIFICANTLY LOWER FRIDAY
WITH HIGHS IN THE UPPER 70S TO MID 80S.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* TSRA THIS EVENING
IZZI
//DISCUSSION...UPDATED 00Z...
TSRA DEVELOPING IN THE VC OF I-80 SHOULD CONTINUE TO FILL IN ALONG
EAST-WEST LINE WITH THIS LINE LIKELY TO DRIFT SLOWLY NORTHWARD
TOWARD CHGO METRO TERMINALS THIS EVENING. ADDITIONAL NORTH-SOUTH
LINE OF TSRA OVER WESTERN ILLINOIS LIKELY TO CONTINUE EAST ACROSS
NORTHERN ILLINOIS AND LIKELY REACH TERMINALS JUST AFTER 0300Z AT
CHGO AND A BIT EARLIER AT RFD. IN THE WAKE OF THE TSRA LOOK FOR
WINDS TO VRB FOR A WHILE BEFORE LOCKING IN MORE W/NW LATE TONIGHT
INTO SUNDAY. CURRENT INDICATIONS ARE THAT WINDS SHOULD BE STRONG
ENOUGH SUNDAY TO PREVENT LAKE BREEZE FROM MAKING IT INTO ORD/MDW.
IZZI
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* MEDIUM CONFIDENCE ON TSRA TIMING/INTENSITY THIS EVENING
* HIGH CONFIDENCE ALL OTHER ELEMENTS
IZZI
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...VFR. SSW WINDS G35KT. VERY HOT/HIGH DENSITY ALTITUDE.
TUESDAY AND WEDNESDAY...VFR. VERY HOT/HIGH DENSITY ALTITUDE.
THURSDAY AND FRIDAY...CHC TSRA...OTHERWISE VFR.
IZZI
&&
.MARINE...
156 PM CDT
AN ACTIVE WEATHER PATTERN ACROSS THE NORTHERN UNITED STATES WILL
PRODUCE SEVERAL LOW PRESSURE SYSTEMS INTO NEXT WEEK...EACH OF THESE
LOWS ARE EXPECTED TO TRACK FROM THE PLAINS ACROSS THE UPPER
MISSISSIPPI VALLEY AND INTO ONTARIO. THESE SYSTEMS WILL PRODUCE
PERIODS OF STRONGER SOUTHERLY WINDS ACROSS THE LAKE. HOWEVER...THE MAIN
CONCERNS ACROSS THE LAKE WILL BE ON MONDAY AS A STRONG PRESSURE
GRADIENT SETS UP. THIS WILL LIKELY SUPPORT A PERIOD OF 30 KT
SOUTHERLY WINDS ON MONDAY INTO MONDAY NIGHT. THERE IS ALSO A
POTENTIAL FOR SOME GALE FORCE GUSTS...ESPECIALLY ACROSS THE
ILLINOIS AND INDIANA NEAR SHORES. STRONG GUSTS UP AROUND 35 KT ARE
POSSIBLE OVER THE LAND AREAS OF NORTHERN ILLINOIS...AND DUE TO
THE EXPECTED OFFSHORE COMPONENT TO THE FLOW...THESE WIND GUSTS
COULD EASILY AFFECT THE NEAR SHORE WATERS.
SOUTH TO SOUTHWESTERLY WINDS SHOULD CONTINUE AROUND 15 TO 25 KT
THROUGH THE MIDDLE OF NEXT WEEK AS WE REMAIN TO THE EAST OF LOW
PRESSURE ACROSS THE PLAINS AND UPPER MIDWEST.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 10 PM SATURDAY.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
655 PM CDT SAT JUN 16 2012
.MESOSCALE DISCUSSION...
458 PM CDT
TWO MAIN FOCUS AREAS THIS AFTERNOON FOR STORMS. STORMS ACROSS
INDIANA ARE HELPING TO OCCASIONALLY HIT SEVERE CRITERIA ON THE NOSE
OF RAP/RUC ANALYZED H7 SPEED MAX AND NOSE OF A THETA E TONGUE. AT
THE SURFACE...DESTABILIZATION HAS ALREADY TAKEN PLACE. DEWPOINTS
IN THE MIDDLE AND UPPER 60S SUPPORT SURFACE BASED CAPE OF
1000-1500 J/KG AVAILABLE TO BE REALIZED. A FEW OF THE STORMS HAVE
BEEN ABLE TO REACH SEVERE CRITERIA...ALLOWING GOLF BALL SIZED HAIL
TO FALL. THIS AREA WILL CONTINUE TO SHIFT EAST THROUGH THE EARLY
EVENING HOURS.
THE SECOND FOCUS IS TIED TO THE MCV/SHORTWAVE MOVING ACROSS
SOUTHERN IOWA AND SHIFTING EAST. MAIN INSTABILITY AXIS SEEMS TO BE
LINED UP DIRECTLY TO THE EAST OF THIS FEATURE AND ACROSS CENTRAL
ILLINOIS. WITHIN THIS CORRIDOR CAPE VALUES OF UP TO 3000 J/KG ARE
PRESENT WITHIN AND THE ATMOSPHERE IS BASICALLY UNTAPPED. CLOUD
TOPS CONTINUE TO RAPIDLY COOL WITH THESE STORMS AND THE FORMATION
OF A COLD POOL MAY BE UNDERWAY. THE EARLIER RAP/RUC HAD BEEN
UNDER DOING LOWER LEVEL WINDS WHEN COMPARED TO PROFILER AND 88D VAD
PROFILES...BUT THE LATEST RUNS SEEM TO HAVE A GOOD HANDLE ON THE
CURRENT SITUATION. ALL GUIDANCE INCREASES THE LOWER LEVEL WINDS
EARLY THIS EVENING AND THIS MAY HELP TO CONVECTION TO FORM INTO A
BOWING SEGMENT AIDED BY A MODERATE REAR INFLOW JET. THERE IS NO
REASON FOR THE ACTIVITY WILL WANE BEFORE IT MOVES EAST AND INTO THE
CWA THIS EVENING...BUT WILL BE MORE OF A WAIT AND SEE TO TELL IF
ANY ORGANIZATION WITH THE COLD POOL INCREASES...OF IF THE STORMS
REMAIN MORE OF THE MULTICELLULAR CLUSTER THAT IS PRESENTLY BEING
NOTED. INCREDIBLY HIGH PWATS /RANGING FROM 1.7 TO ROUGHLY 1.9
INCHES/ WILL ALSO SUPPORT THE TORRENTIAL RAINFALL AND LOCALIZED
FLOODING THREAT. SHEA
.DISCUSSION...
330 PM CDT
A FEW AREAS OF CONCERN OVER THE COMING DAYS. THE FIRST WILL BE THE
POTENTIALLY SEVERE WEATHER THIS EVENING...FOLLOWED BY VERY HOT
WEATHER OPENING UP THE WORK WEEK. FOLLOWING THE SHOWERS AND
THUNDERSTORMS TONIGHT...THE NEXT CHANCE FOR PRECIPITATION WILL NOT
BE UNTIL LATER IN THE WEEK.
IN THE SHORT TERM...GOING THREAT FOR MORE OF AN EXPANDED
COVERAGE OF SHOWERS AND THUNDERSTORMS WILL BE ON THE INCREASE.
SYNOPTIC COLD FRONT WELL TO THE WEST AND ACROSS THE PLAINS AND
TIED TO A LOW LIFTING ACROSS CANADA IS SLOWLY SHIFTING TO THE
EAST. THIS FRONT WILL CONTINUE TO MOVE TOWARDS THE REGION
TONIGHT...BUT WEAKEN CONSIDERABLY BY THE TIME IT REACHES EASTERN
IOWA TONIGHT.
FOR THE IMMEDIATE AFTERNOON...SOUTHWESTERLY FLOW HAS ALLOWED A
RATHER LARGE SURGE OF MOISTURE TO BE TRANSPORTED ACROSS THE REGION.
OUTSIDE OF AREAS THAT SAW RAIN THIS MORNING...DEWPOINTS HAVE JUMPED
FROM AROUND 50 DEGREES TO THE MIDDLE AND UPPER 60S. FORECAST
SOUNDINGS NOT INDICATING MUCH DRY AIR TO IMPEDE THE CLIMB...AND
HAVE NUDGED DEWPOINTS UP ACROSS THE AREA. THE HIGHEST AXIS OF
INSTABILITY IS GENERALLY ANTICIPATED TO REMAIN SOUTH OF THE
AREA...AND CLOSER TO THE IOWA/ILLINOIS/MISSOURI JUNCTION...BUT
MUCAPE VALUES IN THE 1500 TO 2000 J/KG RANGE ARE STILL LIKELY
ACROSS THE EAST THIS AFTERNOON AND UP TO THE WI BORDER. OVERALL
SHEAR IS LOW...AND TIED CLOSER TO THE WAVE LIFTING ACROSS
WISCONSIN. GENERALLY EXPECTING THE SMALL...BUT EFFICIENT RAIN
PRODUCING SHOWERS AND THUNDER TO CONTINUE TO BUBBLE THIS AFTERNOON.
THE GREATEST CHANCES THROUGH AFTERNOON DO APPEAR TO BE EAST OF THE
I57 CORRIDOR...AND WEST OF I39.
THE PRIMARY FOCUS LATER THIS AFTERNOON AND INTO THE EVENING WILL BE
TIED TO A STRONG WAVE THAT IS SLIDING ACROSS THE MISSOURI AND IOWA
BORDER THIS AFTERNOON. PRESENTLY...SHOWER AND THUNDERSTORM CLUSTERS
ARE INCREASING IN OVERALL COVERAGE WITH AND AHEAD OF THIS FEATURE. THE
HIGHEST INSTABILITY AXIS IS WEST AND ACROSS THE MO/IA/IL BORDER
REGION...WITH RAP ANALYZED VALUES NEARING THE 3-4000 MARK. SHEAR
WILL INCREASE AS THE WAVE APPROACHES...AND THE CLUSTER OF STORMS
WILL INCREASE IN COVERAGE AS THEY SHIFT EAST...AND INTO A
SUPPORTIVE ENVIRONMENT. FORECAST SOUNDINGS AND MORNING RAOBS
SHOW A CONSIDERABLE INCREASE OF MOISTURE...WITH PWAT VALUES
JUMPING 2/3 TO 3/4 OF AN INCH ABOVE THEIR MORNING VALUES /AND
PEAKING AROUND THE 1.9 INCH RANGE. AS WAS SEEN EARLIER IN THE
DAY...IT DOES NOT TAKE MUCH FOR THESE STORMS TO PUT OUT A LOT OF
PRECIPITATION. THE LATEST HRRR HAS BEEN A DECENT PROXY FOR
COVERAGE AND TIMING...AND ANTICIPATE COVERAGE TO INCREASE FOR
ROCKFORD BEYOND THE 6P HOUR AND A FEW HOURS BEYOND FOR CHICAGO.
HEAVY RAIN IS THE BIGGEST THREAT WITH THESE STORMS...BUT SOME
POCKETS MAY CONTAIN SUB TO MARGINALLY SEVERE HAIL AND STRONG
WINDS ARE POSSIBLE...THOUGH DIURNALLY BY THE TIME THEY REACH THE
MAJORITY OF THE CWA...IT WILL BE GETTING INTO AN UNFAVORABLE TIME.
THE RAIN WILL BE WELCOME FOR MANY AREAS...BUT OVERALL DROUGHT
BUSTING ONES ARE NOT A LIKELIHOOD.
LONG TERM...THE JET ENGINE WILL TURN ON. THE COLD FRONT THAT IS
MARCHING EAST ACROSS THE MISSISSIPPI VALLEY TODAY WILL BASICALLY
WASH OUT AND ONLY DROP DEWPOINTS DOWN INTO THE LOWER 60S TO UPPER
50S...AND KEEP HIGH TEMPERATURES INTO THE 80S TOMORROW. BIG H8
THERMAL RIDGE WILL SLOWLY SHIFT EAST FROM THE PLAINS AND CLOSE TO
THE REGION...WARMING THE AREA BACK UP MONDAY. ENDED UP BUMPING UP HIGHS
FOR BOTH MONDAY AND TUESDAY TO BE INTO THE UPPER 90 RANGE /AND CAN
SEE A POSSIBLE 100 MARK SOMEWHERE ACROSS THE REGION/ IN THAT TIME.
NOT ONLY WILL IT BE HOT ON MONDAY...IT WILL BE INCREDIBLY WINDY.
FORECAST SOUNDINGS SHOW MIXED LAYER WINDS BREACHING THE 30KT
RANGE. THE POTENTIAL FOR CRITICAL FIRE WEATHER CONDITIONS WILL BE
ELEVATED...BUT SPECIFICS WILL BE FOLLOWED UP IN THE FIRE WEATHER
DISCUSSIONS THROUGH THE WEEKEND. THE 90S WILL CONTINUE THROUGH
WEDNESDAY...BEFORE A FRONT MOVES THROUGH THURSDAY AND COOLS OFF
THE AREA WITH THE NEXT CHANCE FOR SHOWERS AND STORMS.
SHEA
&&
.DISCUSSION...
330 PM CDT
A FEW AREAS OF CONCERN OVER THE COMING DAYS. THE FIRST WILL BE THE
POTENTIALLY SEVERE WEATHER THIS EVENING...FOLLOWED BY VERY HOT
WEATHER OPENING UP THE WORK WEEK. FOLLOWING THE SHOWERS AND
THUNDERSTORMS TONIGHT...THE NEXT CHANCE FOR PRECIPITATION WILL NOT
BE UNTIL LATER IN THE WEEK.
IN THE SHORT TERM...GOING THREAT FOR MORE OF AN EXPANDED
COVERAGE OF SHOWERS AND THUNDERSTORMS WILL BE ON THE INCREASE.
SYNOPTIC COLD FRONT WELL TO THE WEST AND ACROSS THE PLAINS AND
TIED TO A LOW LIFTING ACROSS CANADA IS SLOWLY SHIFTING TO THE
EAST. THIS FRONT WILL CONTINUE TO MOVE TOWARDS THE REGION
TONIGHT...BUT WEAKEN CONSIDERABLY BY THE TIME IT REACHES EASTERN
IOWA TONIGHT.
FOR THE IMMEDIATE AFTERNOON...SOUTHWESTERLY FLOW HAS ALLOWED A
RATHER LARGE SURGE OF MOISTURE TO BE TRANSPORTED ACROSS THE REGION.
OUTSIDE OF AREAS THAT SAW RAIN THIS MORNING...DEWPOINTS HAVE JUMPED
FROM AROUND 50 DEGREES TO THE MIDDLE AND UPPER 60S. FORECAST
SOUNDINGS NOT INDICATING MUCH DRY AIR TO IMPEDE THE CLIMB...AND
HAVE NUDGED DEWPOINTS UP ACROSS THE AREA. THE HIGHEST AXIS OF
INSTABILITY IS GENERALLY ANTICIPATED TO REMAIN SOUTH OF THE
AREA...AND CLOSER TO THE IOWA/ILLINOIS/MISSOURI JUNCTION...BUT
MUCAPE VALUES IN THE 1500 TO 2000 J/KG RANGE ARE STILL LIKELY
ACROSS THE EAST THIS AFTERNOON AND UP TO THE WI BORDER. OVERALL
SHEAR IS LOW...AND TIED CLOSER TO THE WAVE LIFTING ACROSS
WISCONSIN. GENERALLY EXPECTING THE SMALL...BUT EFFICIENT RAIN
PRODUCING SHOWERS AND THUNDER TO CONTINUE TO BUBBLE THIS AFTERNOON.
THE GREATEST CHANCES THROUGH AFTERNOON DO APPEAR TO BE EAST OF THE
I57 CORRIDOR...AND WEST OF I39.
THE PRIMARY FOCUS LATER THIS AFTERNOON AND INTO THE EVENING WILL BE
TIED TO A STRONG WAVE THAT IS SLIDING ACROSS THE MISSOURI AND IOWA
BORDER THIS AFTERNOON. PRESENTLY...SHOWER AND THUNDERSTORM CLUSTERS
ARE INCREASING IN OVERALL COVERAGE WITH AND AHEAD OF THIS FEATURE. THE
HIGHEST INSTABILITY AXIS IS WEST AND ACROSS THE MO/IA/IL BORDER
REGION...WITH RAP ANALYZED VALUES NEARING THE 3-4000 MARK. SHEAR
WILL INCREASE AS THE WAVE APPROACHES...AND THE CLUSTER OF STORMS
WILL INCREASE IN COVERAGE AS THEY SHIFT EAST...AND INTO A
SUPPORTIVE ENVIRONMENT. FORECAST SOUNDINGS AND MORNING RAOBS
SHOW A CONSIDERABLE INCREASE OF MOISTURE...WITH PWAT VALUES
JUMPING 2/3 TO 3/4 OF AN INCH ABOVE THEIR MORNING VALUES /AND
PEAKING AROUND THE 1.9 INCH RANGE. AS WAS SEEN EARLIER IN THE
DAY...IT DOES NOT TAKE MUCH FOR THESE STORMS TO PUT OUT A LOT OF
PRECIPITATION. THE LATEST HRRR HAS BEEN A DECENT PROXY FOR
COVERAGE AND TIMING...AND ANTICIPATE COVERAGE TO INCREASE FOR
ROCKFORD BEYOND THE 6P HOUR AND A FEW HOURS BEYOND FOR CHICAGO.
HEAVY RAIN IS THE BIGGEST THREAT WITH THESE STORMS...BUT SOME
POCKETS MAY CONTAIN SUB TO MARGINALLY SEVERE HAIL AND STRONG
WINDS ARE POSSIBLE...THOUGH DIURNALLY BY THE TIME THEY REACH THE
MAJORITY OF THE CWA...IT WILL BE GETTING INTO AN UNFAVORABLE TIME.
THE RAIN WILL BE WELCOME FOR MANY AREAS...BUT OVERALL DROUGHT
BUSTING ONES ARE NOT A LIKELIHOOD.
LONG TERM...THE JET ENGINE WILL TURN ON. THE COLD FRONT THAT IS
MARCHING EAST ACROSS THE MISSISSIPPI VALLEY TODAY WILL BASICALLY
WASH OUT AND ONLY DROP DEWPOINTS DOWN INTO THE LOWER 60S TO UPPER
50S...AND KEEP HIGH TEMPERATURES INTO THE 80S TOMORROW. BIG H8
THERMAL RIDGE WILL SLOWLY SHIFT EAST FROM THE PLAINS AND CLOSE TO
THE REGION...WARMING THE AREA BACK UP MONDAY. ENDED UP BUMPING UP HIGHS
FOR BOTH MONDAY AND TUESDAY TO BE INTO THE UPPER 90 RANGE /AND CAN
SEE A POSSIBLE 100 MARK SOMEWHERE ACROSS THE REGION/ IN THAT TIME.
NOT ONLY WILL IT BE HOT ON MONDAY...IT WILL BE INCREDIBLY WINDY.
FORECAST SOUNDINGS SHOW MIXED LAYER WINDS BREACHING THE 30KT
RANGE. THE POTENTIAL FOR CRITICAL FIRE WEATHER CONDITIONS WILL BE
ELEVATED...BUT SPECIFICS WILL BE FOLLOWED UP IN THE FIRE WEATHER
DISCUSSIONS THROUGH THE WEEKEND. THE 90S WILL CONTINUE THROUGH
WEDNESDAY...BEFORE A FRONT MOVES THROUGH THURSDAY AND COOLS OFF
THE AREA WITH THE NEXT CHANCE FOR SHOWERS AND STORMS.
SHEA
&&
.FIRE WEATHER...
515 PM CDT
HOT AND WINDY CONDITIONS MAY RESULT IN CRITICAL AND DANGEROUS
FIRE WEATHER CONDITIONS ON MONDAY.
FOR THE REMAINDER OF THIS AFTERNOON AND THIS EVENING...INCREASING
DEWPOINTS ACROSS THE AREA WILL LIMIT MINIMUM RELATIVE HUMIDITY
VALUES TO 35 TO 40 PERCENT AS TEMPERATURES TOP OUT IN THE LOWER
90S. WINDS WILL OUT OF THE SOUTHWEST AT 10 TO 15 MPH...GUSTING
TO AROUND 20 MPH.
SCATTERED SHOWERS AND THUNDERSTORMS WILL BRING WETTING RAIN TO
SOME LOCATIONS THROUGH EARLY THIS EVENING. THERE IS THE POTENTIAL
FOR ADDITIONAL THUNDERSTORMS THROUGH LATE THIS EVENING WHICH MAY
BRING SOME ADDITIONAL WETTING RAIN...AND SOME THUNDERSTORMS MAY
EVEN BRING SOME LOCALLY HEAVY RAINFALL.
WHILE RED FLAG CRITERIA WILL NOT BE REACHED TODAY...THE RECENT
VERY DRY CONDITIONS COMBINED WITH HIGH TEMPERATURES...MODESTLY
LOW DEW POINTS AND MODERATELY STRONG WINDS WILL RESULT IN ELEVATED
WILDFIRE DANGER.
A WEAK...COLD FRONT WILL MOVE INTO THE AREA TONIGHT AND EARLY
SUNDAY MORNING...BRINGING SLIGHTLY COOLER AIR...WITH HIGHS IN THE
MID AND UPPER 80S.
MUCH WARMER AIR WILL RETURN MONDAY WITH SOUTHWEST WINDS GUSTING AS
HIGH AS 40 MPH. SOME QUESTION REMAINS AS TO HOW LOW DEWPOINTS MAY
MAY DROP MONDAY AFTERNOON IF DRIER AIR ALOFT MIXES DOWN TO THE
SURFACE. CURRENTLY...EXPECT THAT HIGH TEMPERATURES WILL BE IN THE
MIDDLE 90S. EVEN DEWPOINTS IN THE LOWER 60S WILL CAUSE RELATIVE
HUMIDITY VALUES TO DROP CLOSE TO 30 PERCENT OVER MUCH OF THE AREA
AND DEWPOINTS IN THE UPPER 50S WILL BRING RELATIVE HUMIDITY LEVELS
IN RED FLAG CRITERIA RANGE.
ANOTHER WILD CARD IS HOW RAINFALL OCCURRING THIS AFTERNOON AND HOW
MUCH ADDITIONAL RAINFALL THAT MAY OCCUR LATER THIS EVENING WILL
AFFECT FUEL MOISTURE LEVELS AS WELL AS SOIL MOISTURE LEVELS. THE
GREATER THE AMOUNT OF WIDESPREAD WETTING RAIN TODAY AND TONIGHT...
THE MORE LIKELY THAT RELATIVE HUMIDITY LEVELS WILL BE ABOVE RED
FLAG CRITERIA.
HOWEVER...EVEN IF RELATIVE HUMIDITY LEVELS ARE ABOVE RED FLAG
CRITERIA...THE EXPECTED TEMPERATURE AND WIND CONDITIONS COMBINED
WITH THE RECENT DRY CONDITIONS WILL ELEVATE THE FIRE DANGER...
ESPECIALLY FOR ANY AREAS THAT DO NOT RECEIVE MUCH WETTING RAINFALL
THIS EVENING AND TONIGHT AS FUEL MOISTURE WILL REMAIN QUITE LOW.
WHILE HIGH TEMPERATURES ARE EXPECTED TO REMAIN IN THE LOWER AND
MID 90S FOR TUESDAY AND WEDNESDAY...DEW POINTS ARE EXPECTED TO
SIGNIFICANTLY INCREASE...PREVENTING MINIMUM RELATIVE HUMIDITY
VALUES FROM DROPPING TO CRITICAL LEVELS.
ANOTHER COLD FRONT WILL MOVE INTO THE AREA THURSDAY...BRINGING
ANOTHER CHANCE OF SHOWERS AND THUNDERSTORMS. DAYTIME TEMPERATURES
WILL BE SOMEWHAT LOWER THURSDAY...AND SIGNIFICANTLY LOWER FRIDAY
WITH HIGHS IN THE UPPER 70S TO MID 80S.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* TSRA THIS EVENING
IZZI
//DISCUSSION...UPDATED 00Z...
TSRA DEVELOPING IN THE VC OF I-80 SHOULD CONTINUE TO FILL IN ALONG
EAST-WEST LINE WITH THIS LINE LIKELY TO DRIFT SLOWLY NORTHWARD
TOWARD CHGO METRO TERMINALS THIS EVENING. ADDITIONAL NORTH-SOUTH
LINE OF TSRA OVER WESTERN ILLINOIS LIKELY TO CONTINUE EAST ACROSS
NORTHERN ILLINOIS AND LIKELY REACH TERMINALS JUST AFTER 0300Z AT
CHGO AND A BIT EARLIER AT RFD. IN THE WAKE OF THE TSRA LOOK FOR
WINDS TO VRB FOR A WHILE BEFORE LOCKING IN MORE W/NW LATE TONIGHT
INTO SUNDAY. CURRENT INDICATIONS ARE THAT WINDS SHOULD BE STRONG
ENOUGH SUNDAY TO PREVENT LAKE BREEZE FROM MAKING IT INTO ORD/MDW.
IZZI
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* MEDIUM CONFIDENCE ON TSRA TIMING/INTENSITY THIS EVENING
* HIGH CONFIDENCE ALL OTHER ELEMENTS
IZZI
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...VFR. SSW WINDS G35KT. VERY HOT/HIGH DENSITY ALTITUDE.
TUESDAY AND WEDNESDAY...VFR. VERY HOT/HIGH DENSITY ALTITUDE.
THURSDAY AND FRIDAY...CHC TSRA...OTHERWISE VFR.
IZZI
&&
.MARINE...
156 PM CDT
AN ACTIVE WEATHER PATTERN ACROSS THE NORTHERN UNITED STATES WILL
PRODUCE SEVERAL LOW PRESSURE SYSTEMS INTO NEXT WEEK...EACH OF THESE
LOWS ARE EXPECTED TO TRACK FROM THE PLAINS ACROSS THE UPPER
MISSISSIPPI VALLEY AND INTO ONTARIO. THESE SYSTEMS WILL PRODUCE
PERIODS OF STRONGER SOUTHERLY WINDS ACROSS THE LAKE. HOWEVER...THE MAIN
CONCERNS ACROSS THE LAKE WILL BE ON MONDAY AS A STRONG PRESSURE
GRADIENT SETS UP. THIS WILL LIKELY SUPPORT A PERIOD OF 30 KT
SOUTHERLY WINDS ON MONDAY INTO MONDAY NIGHT. THERE IS ALSO A
POTENTIAL FOR SOME GALE FORCE GUSTS...ESPECIALLY ACROSS THE
ILLINOIS AND INDIANA NEAR SHORES. STRONG GUSTS UP AROUND 35 KT ARE
POSSIBLE OVER THE LAND AREAS OF NORTHERN ILLINOIS...AND DUE TO
THE EXPECTED OFFSHORE COMPONENT TO THE FLOW...THESE WIND GUSTS
COULD EASILY AFFECT THE NEAR SHORE WATERS.
SOUTH TO SOUTHWESTERLY WINDS SHOULD CONTINUE AROUND 15 TO 25 KT
THROUGH THE MIDDLE OF NEXT WEEK AS WE REMAIN TO THE EAST OF LOW
PRESSURE ACROSS THE PLAINS AND UPPER MIDWEST.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 10 PM SATURDAY.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
641 PM CDT SAT JUN 16 2012
.DISCUSSION...
ISSUED 145 PM CDT SAT JUN 16 2012
SOUTHERN END OF MCV COMBINED WITH AN UNSTABLE AIR MASS WAS ENOUGH
TO PRODUCE SOME WIDELY SCATTERED CONVECTION ACROSS EASTERN ILLINOIS
EARLY THIS AFTERNOON. A MUCH STRONGER UPPER WAVE ACRS THE NRN PLAINS
WILL START TO PUSH THE REMNANT MCV/SHORTWAVE OFF TO OUR EAST. EARLY
AFTN TEMPERATURES HAVE RISEN INTO THE UPPER 80S TO LOWER 90S WITH
DEW POINTS IN THE UPPER 60S TO LOWER 70S.
SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT
MAIN CONCERNS THIS PERIOD WILL INCLUDE COVERAGE OF CONVECTION AND
MUCH NEEDED RAINFALL ALONG COLD FRONT THIS EVENING...AND THE
THREAT FOR REDEVELOPMENT ALONG THE SLOW MOVING FRONT AGAIN SUNDAY
AFTERNOON...FOLLOWED BY HOT AND HUMID WEATHER THRU AT LEAST THE
FIRST HALF OF THE WORK WEEK.
CONSENSUS OF HI-RES MODEL SOLUTIONS SUGGEST A COMPLEX OF STORMS
WILL EVOLVE INTO MORE OF A QUASI-LINEAR CONVECTIVE SYSTEM BY LATE
AFTERNOON WITH THE PRIMARY SEVERE THREAT BEING FROM STRAIGHT LINE
WIND DAMAGE. FORECAST SOUNDINGS CONTINUE TO SHOW SURFACE BASE CAPES
OF AROUND 2500 J/KG INTO THIS EVENING WITH 0-6KM SHEAR VALUES OF
AROUND 20 TO 25 KTS. JUST ENOUGH LOW LEVEL DRY AIR IN PLACE ON
SOUNDINGS TO SUGGEST A THREAT FOR SOME DOWNBURST WINDS IN SOME OF
THE MORE ORGANIZED UPDRAFTS/BOWING SEGMENTS. THE MAJORITY OF THE
MODELS INDICATE A GRADUAL WEAKENING TREND IN THE CONVECTION AFTER
SUNSET AS WE LOSE THE DAYTIME HEATING/INSTABILITY. DUE TO THE MORE
PROGRESSIVE NATURE OF THE CONVECTION LATER THIS AFTERNOON AND THIS
EVENING...RAINFALL AMOUNTS LOOK TO RANGE FROM A QUARTER TO ONE
HALF INCH...WITH LOCAL 1 INCH AMOUNTS POSSIBLE WITH SOME OF THE
MORE INTENSE CELLS EARLY THIS EVENING.
WILL CONTINUE TO HAVE LOW CHANCE POPS ON SUNDAY...ESPECIALLY
DURING THE MORNING. HOWEVER...SOME OF THE HI-RES REF SIMULATIONS
INDICATE THE ORGANIZED CONVECTION THAT MOVES THRU OUR AREA WILL
SHIFT EAST AND SOUTHEAST ACROSS PARTS OF SE IL BY TOMORROW AFTN
WITH ANY REDEVELOPMENT OCCURRING ALONG OR JUST SOUTH OF THE
REMNANT OUTFLOW BOUNDARY. NOT REAL CONFIDENT ON PLACEMENT OF
BOUNDARY AT THIS TIME SO WILL CONTINUE TO CARRY SOME MENTIONABLE
POPS...ESPECIALLY ACRS THE SOUTHEAST TOMORROW AFTN. WITH UPPER
LEVEL HEIGHTS BUILDING ONCE AGAIN LATE SUNDAY INTO MONDAY...THE
BOUNDARY SHOULD SHIFT TO OUR NORTH BY SUNDAY NIGHT OR EARLY
MONDAY. WILL CONTINUE TO HOLD ON TO LOW CHANCE POPS WITH THE
WARM FRONT ON SUNDAY NIGHT...WITH HOT AND DRY WEATHER MOVING
IN FOR THE REMAINDER OF THE SHORT TERM. AFTERNOON HIGHS ON MONDAY
AND TUESDAY SHOULD SOAR INTO THE LOW TO MID 90S.
LONG TERM...WEDNESDAY THROUGH SATURDAY
UPPER LEVEL RIDGE THAT WILL BRING US HOT WEATHER AT LEAST INTO
WEDNESDAY IS FORECAST TO BREAK DOWN AS A FAIRLY SIGNIFICANT UPPER
LEVEL WAVE WILL PUSH ACRS THE NORTHERN PLAINS MIDWEEK. THE LATEST
ECMWF IS A BIT FASTER THAN PREVIOUS RUNS IN BREAKING DOWN THE
RIDGE ON WEDNESDAY ALLOWING A COLD FRONT TO SURGE ACRS THE AREA
THURSDAY MORNING. THE LATEST CANADIAN MODEL IS ALSO SHOWING A
FASTER TREND IN BREAKING DOWN THE RIDGE AS WELL...AS A RESULT...THE
FRONT AND CONVECTION CHANCES PUSH IN TO OUR AREA LATE WED NIGHT
INTO THU. WILL ONLY CARRY SLIGHT CHANCES FAR NORTHWEST LATE WED
NIGHT WITH THE BEST THREAT FOR SHOWERS AND THUNDERSTORMS BEING ON
THURSDAY IN THURSDAY EVENING AS THE FRONT SETTLES SOUTHEAST ACRS
THE AREA. IF LATER MODEL RUNS CONTINUE WITH THE FAST TREND OF THE
FRONT WILL PROBABLY BE ABLE TO REMOVE RAIN CHANCES THURSDAY NIGHT
INTO FRIDAY AS BOTH THE CANADIAN AND GEM MODELS BUILD A FAIRLY
STRONG TROF NORTH OF THE GREAT LAKES PUTTING US IN A COOLER AND
LESS HUMID AIR MASS. HOWEVER...MOST MEDIUM RANGE MODELS INDICATE
EVEN THOUGH WE MAY TRANSLATE TO A NWLY FLOW PATTERN...THE STRONGER
FLOW WILL BE JUST TO OUR NORTH SUGGESTING ANY SE MOVING SHORTWAVE
TOPPING THE RIDGE TO OUR WEST MAY BRING IN CONVECTION TO PARTS OF
THE MIDWEST LATE IN THE WEEK OR NEXT WEEKEND. AT THIS POINT...WILL
KEEP PRECIP OUT ON SATURDAY.
SMITH
&&
.AVIATION...
ISSUED 641 PM CDT SAT JUN 16 2012
LARGE AREA OF SHOWERS AND THUNDERSTORMS PUSHING EAST ACROSS WEST
CENTRAL ILLINOIS...BUT HAS BEEN SHOWING SOME SIGNS OF WEAKENING.
KPIA MOST LIKELY TO BE IMPACTED BY THE STRONGER STORMS WITH SOME
GUSTS OF 35 KNOTS HIGHER POSSIBLE IN THE 00-01Z TIME FRAME. HAVE
INCLUDED SOME TEMPO GROUPS TO PIN DOWN THE MORE LIKELY TIME FRAMES
OF MORE SUSTAINED CONVECTION. LATEST HRRR MODEL SUGGESTS THE
SHOWERS/STORMS SHOULD LARGELY BE DONE FROM KBMI-KSPI WESTWARD BY
ABOUT 06Z...AND AROUND 09Z AT KCMI. WINDS SHOULD BECOME MORE
WESTERLY AFTER THE RAIN ENDS WITH THE ARRIVAL OF A WEAK COLD
FRONT...BUT IS EXPECTED TO TREND BACK TOWARD THE SOUTHWEST SUNDAY
AFTERNOON AS THE FRONT WASHES OUT.
GEELHART
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
644 AM CDT FRI JUN 15 2012
.UPDATE...
THE NOCTURNAL MCS IS RAPIDLY DECAYING AND THIS WILL CONTINUE OVER
THE NEXT SEVERAL HOURS. ONCE THE CONVECTION DISSIPATES THE DENSE
CI/CS SHIELD ACROSS THE AREA SHOULD BEGIN THINNING RATHER QUICKLY
ALLOWING TEMPERATURES TO CLIMB THIS AFTERNOON.
TRENDS FROM THE RAP MODEL REGARDING CONVECTION THIS AFTERNOON ARE
NOT OVERLY GOOD. FCST CONVECTIVE TEMPERATURES ARE STILL IN THE
LOW TO MID 90S FOR THIS AFTERNOON WHICH IS HIGHER THAN THE FCST
MAX TEMPERATURES. THE MCV FROM THE NOCTURNAL MCS IS EXPECTED TO
MODIFY THE ATMOSPHERE THIS AFTERNOON AND LOWER CONVECTIVE
TEMPERATURES. THE 06Z WRF RUN SUGGESTS CONVECTIVE TEMPERATURES IN
THE LOW TO MID 90S DURING PEAK HEATING AS WELL.
SO...WILL KEEP THE IDEA OF SOME CONVECTION DEVELOPING DURING THE
MID TO LATE AFTERNOON OVER ROUGHLY THE WESTERN THIRD OF THE CWFA
AS THE MCV MODIFIES THE ATMOSPHERE. THE PRESENCE OF THE MCV
ACROSS IOWA AND A COOLING ATMOSPHERE WITH SUNSET SHOULD RESULT IN
CONVECTION SLOWLY DEVELOPING WEST OF THE MISSISSIPPI DURING THE
EVENING. ..08..
&&
.AVIATION...
VFR WX IS EXPECTED THROUGH 00Z/16. DENSE CS/CI CLOUDS WILL THIN AS
THE DAY PROGRESSES AND A WEAK FRONT SLOWLY MOVES EAST ACROSS IOWA.
CONVECTION MAY DVLP AFT 20Z/15 BUT SHOULD HAVE A BETTER CHANCE OF
DVLPG AFT 00Z/16 ACROSS IOWA. BASED ON MODEL TRENDS...KCID/KDBQ
APPEAR TO HAVE BETTER CHANCE OF SEEING VCTS AFT 00Z/16. VFR WX
SHOULD BE SEEN AFT 00Z/16 AT ALL TAF SITES. IF TSRA WOULD IMPACT
KCID/DBQ THEN MVFR WITH BORDERLINE IFR CONDITIONS MAY BE POSSIBLE
AFTER 02Z/16. ..08..
&&
.PREV DISCUSSION... /ISSUED 314 AM CDT FRI JUN 15 2012/
SYNOPSIS...
06Z SFC ANALYSIS HAS MESO WAKE LOWS NEAR KOMA AND KHSI WITH A MESO
HIGH IN SOUTH CENTRAL KS. A LEAD MESO LOW WAS NEAR KSTJ THAT HAD A
BOUNDARY RUNNING SOUTHEAST INTO THE TENNESSEE VALLEY. DEW POINTS
WERE IN THE 40S AND 50S ACROSS THE GREAT LAKES WITH 60S FROM THE
SOUTHERN PLAINS INTO THE UPPER MISSISSIPPI VALLEY. SATELLITE/RADAR
IMAGE HAS A LARGE MCS/MCC OVER THE PLAINS WITH A DECAYING MCS ACROSS
WISCONSIN.
SHORT TERM...TODAY AND TONIGHT...
MCS TOOL COMBINED WITH CURRENT TRENDS FROM THE RAP/RADAR INDICATE
THAT THE MORNING HOURS WILL BE DRY ACROSS THE CWFA. THE PLAINS MCS
WILL SLOWLY DECAY DURING THE MORNING THAT WILL ALLOW THE DENSE CI/CS
TO THIN ACROSS THE AREA. THE AFTERNOON HOURS IS WHERE THINGS BECOME
MORE PROBLEMATIC.
THE CONVECTIVE INDUCED MCV IS PROGGED BY THE RAP TO SLOWLY MOVE
NORTHEAST DURING THE MORNING. EXTRAPOLATION OF THE 12 HR RAP FCST
COMBINED WITH INPUT FROM THE GEM WOULD BRING THE MCV INTO CENTRAL
IOWA BY EARLY EVENING. FCST SOUNDINGS SHOW A CONSIDERABLE CAP IN
PLACE ACROSS THE AREA UNTIL LATE AFTERNOON. A CONCERN IS THE IMPLIED
CONVECTIVE TEMPERATURES IN THE MID AND UPPER 90S IN THE FCST
SOUNDINGS. IF THESE NUMBERS PROVE CORRECT THEN THE POTENTIAL FOR ANY
CONVECTION THIS AFTERNOON IS NOT GOOD. GOING ON THE ASSUMPTION THAT
THE MCS AND REMNANT MCV WILL MODIFY THE ENVIRONMENT AND LOWER
CONVECTIVE TEMPERATURES SOME SCHC TO LOW CHC POPS WILL BE DONE
DURING THE PEAK HEATING HOURS WEST OF A DBQ TO LURAY MO LINE.
TONIGHT...IF CONVECTION DEVELOPS IN THE WESTERN QUARTER TO THIRD OF
THE CWFA LATE THIS AFTERNOON IT WILL MAKE MINIMAL HEADWAY EASTWARD
DURING THE EVENING HOURS. AS THE ATMOSPHERE COOLS DURING THE EVENING
ADDITIONAL CONVECTION SHOULD DEVELOP DUE TO THE FORCING FROM THE MCV
ACROSS MOST OF THE CWFA AFTER MIDNIGHT. HOWEVER...THE BETTER FORCING
REMAINS CONFINED OVER THE WESTERN THIRD OF THE CWFA. THE LIFT TOOL
HAS A NICE THETA E GRADIENT OVER ROUGHLY THE WESTERN HALF OF THE
CWFA. THUS THE HIGHER POP CHANCES WILL BE OVER ABOUT THE WESTERN 40
PERCENT OF THE CWFA. ..08..
LONG TERM...SATURDAY THROUGH THURSDAY...
MAIN CONCERNS IN THE LONG TERM ARE THE PAIR OF FRONTAL PASSAGES...ONE
THIS WEEKEND AND THE SECOND LATER NEXT WEEK...AND THE MCV LEFTOVER
FROM THE CONVECTION TO SOUTHWEST THIS MORNING. OTHERWISE...MOST
OF THE ACTION REMAINS TO OUR NORTH LEAVING US IN SEASONABLY WARM
AND SOMEWHAT HUMID WEATHER.
00Z MODELS DRIFT THE MCV SLOWLY NORTHEAST WHICH SHOULD BE A
TRIGGER FOR THUNDERSTORMS INTO EARLY SATURDAY. POP CHANCES ARE
BEST WEST OF THE MISSISSIPPI BASED ON THE CONSENSUS TRACK OF THE
VORT MAX. AS THE MCV DRIFTS OUT OF THE AREA...A WEAK FRONT WILL PUSH
THROUGH THE CWA DURING THE OVERNIGHT HOURS EARLY SUNDAY PROVIDING
ANOTHER FOCUS FOR THUNDERSTORM ACTIVITY.
THE FRONT LATER THIS WEEK LOOKS STRONGER AND WILL LIKELY PROVIDE A
BETTER FOCUS FOR STORMS AROUND THURSDAY...THOUGH THE GFS AND ECMWF
DIFFER IN HOW THEY HANDLE UPPER AIR FEATURES. ANY POTENTIAL SEVERE
WEATHER THREAT OR EVALUATION OF QPF IS HARD TO DEFINE AT THIS
POINT.
ANY COOLER WEATHER FOLLOWING THE SUNDAY FRONT WILL BE SHORT-LIVED
AS RETURN FLOW SETS UP QUICKLY. MODELS BRING IN WARMER AIR ON
FAVORED SOUTHWEST FLOW...THUS HAVE GONE ABOVE GUIDANCE TEMPS
DURING THE DAY. TEMPERED DEW POINT FORECASTS BACK A TAD GIVEN POOR
MODEL PERFORMANCE WITH THAT PARAMETER...ESPECIALLY FROM THE GFS
WHICH SIMPLY LOOKS BAD IN THAT REGARD.
WOLF
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
314 AM CDT FRI JUN 15 2012
.SYNOPSIS...
06Z SFC ANALYSIS HAS MESO WAKE LOWS NEAR KOMA AND KHSI WITH A MESO
HIGH IN SOUTH CENTRAL KS. A LEAD MESO LOW WAS NEAR KSTJ THAT HAD A
BOUNDARY RUNNING SOUTHEAST INTO THE TENNESSEE VALLEY. DEW POINTS
WERE IN THE 40S AND 50S ACROSS THE GREAT LAKES WITH 60S FROM THE
SOUTHERN PLAINS INTO THE UPPER MISSISSIPPI VALLEY. SATELLITE/RADAR
IMAGE HAS A LARGE MCS/MCC OVER THE PLAINS WITH A DECAYING MCS ACROSS
WISCONSIN.
&&
.SHORT TERM...TODAY AND TONIGHT...
MCS TOOL COMBINED WITH CURRENT TRENDS FROM THE RAP/RADAR INDICATE
THAT THE MORNING HOURS WILL BE DRY ACROSS THE CWFA. THE PLAINS MCS
WILL SLOWLY DECAY DURING THE MORNING THAT WILL ALLOW THE DENSE CI/CS
TO THIN ACROSS THE AREA. THE AFTERNOON HOURS IS WHERE THINGS BECOME
MORE PROBLEMATIC.
THE CONVECTIVE INDUCED MCV IS PROGGED BY THE RAP TO SLOWLY MOVE
NORTHEAST DURING THE MORNING. EXTRAPOLATION OF THE 12 HR RAP FCST
COMBINED WITH INPUT FROM THE GEM WOULD BRING THE MCV INTO CENTRAL
IOWA BY EARLY EVENING. FCST SOUNDINGS SHOW A CONSIDERABLE CAP IN
PLACE ACROSS THE AREA UNTIL LATE AFTERNOON. A CONCERN IS THE IMPLIED
CONVECTIVE TEMPERATURES IN THE MID AND UPPER 90S IN THE FCST
SOUNDINGS. IF THESE NUMBERS PROVE CORRECT THEN THE POTENTIAL FOR ANY
CONVECTION THIS AFTERNOON IS NOT GOOD. GOING ON THE ASSUMPTION THAT
THE MCS AND REMNANT MCV WILL MODIFY THE ENVIRONMENT AND LOWER
CONVECTIVE TEMPERATURES SOME SCHC TO LOW CHC POPS WILL BE DONE
DURING THE PEAK HEATING HOURS WEST OF A DBQ TO LURAY MO LINE.
TONIGHT...IF CONVECTION DEVELOPS IN THE WESTERN QUARTER TO THIRD OF
THE CWFA LATE THIS AFTERNOON IT WILL MAKE MINIMAL HEADWAY EASTWARD
DURING THE EVENING HOURS. AS THE ATMOSPHERE COOLS DURING THE EVENING
ADDITIONAL CONVECTION SHOULD DEVELOP DUE TO THE FORCING FROM THE MCV
ACROSS MOST OF THE CWFA AFTER MIDNIGHT. HOWEVER...THE BETTER FORCING
REMAINS CONFINED OVER THE WESTERN THIRD OF THE CWFA. THE LIFT TOOL
HAS A NICE THETA E GRADIENT OVER ROUGHLY THE WESTERN HALF OF THE
CWFA. THUS THE HIGHER POP CHANCES WILL BE OVER ABOUT THE WESTERN 40
PERCENT OF THE CWFA. ..08..
.LONG TERM...SATURDAY THROUGH THURSDAY...
MAIN CONCERNS IN THE LONG TERM ARE THE PAIR OF FRONTAL PASSAGES...ONE
THIS WEEKEND AND THE SECOND LATER NEXT WEEK...AND THE MCV LEFTOVER
FROM THE CONVECTION TO SOUTHWEST THIS MORNING. OTHERWISE...MOST
OF THE ACTION REMAINS TO OUR NORTH LEAVING US IN SEASONABLY WARM
AND SOMEWHAT HUMID WEATHER.
00Z MODELS DRIFT THE MCV SLOWLY NORTHEAST WHICH SHOULD BE A
TRIGGER FOR THUNDERSTORMS INTO EARLY SATURDAY. POP CHANCES ARE
BEST WEST OF THE MISSISSIPPI BASED ON THE CONSENSUS TRACK OF THE
VORT MAX. AS THE MCV DRIFTS OUT OF THE AREA...A WEAK FRONT WILL PUSH
THROUGH THE CWA DURING THE OVERNIGHT HOURS EARLY SUNDAY PROVIDING
ANOTHER FOCUS FOR THUNDERSTORM ACTIVITY.
THE FRONT LATER THIS WEEK LOOKS STRONGER AND WILL LIKELY PROVIDE A
BETTER FOCUS FOR STORMS AROUND THURSDAY...THOUGH THE GFS AND ECMWF
DIFFER IN HOW THEY HANDLE UPPER AIR FEATURES. ANY POTENTIAL SEVERE
WEATHER THREAT OR EVALUATION OF QPF IS HARD TO DEFINE AT THIS
POINT.
ANY COOLER WEATHER FOLLOWING THE SUNDAY FRONT WILL BE SHORT-LIVED
AS RETURN FLOW SETS UP QUICKLY. MODELS BRING IN WARMER AIR ON
FAVORED SOUTHWEST FLOW...THUS HAVE GONE ABOVE GUIDANCE TEMPS
DURING THE DAY. TEMPERED DEW POINT FORECASTS BACK A TAD GIVEN POOR
MODEL PERFORMANCE WITH THAT PARAMETER...ESPECIALLY FROM THE GFS
WHICH SIMPLY LOOKS BAD IN THAT REGARD.
WOLF
&&
.AVIATION...
MCS IN THE PLAINS WILL SLOWLY DECAY THROUGH 18Z/15 LEAVING HIGH
CI/CS CLOUDS ACROSS THE AREA. THUS VFR WX IS EXPECTED THROUGH
20Z/15. AFT 20Z/15 DIURNAL CONVECTION MAY DVLP IF THE THERMAL
FORCING CAN BREAK THROUGH THE WARM AIR ALOFT. LIFT FROM THE CURRENT
PLAINS MCS WILL MOVE ACROSS IOWA TONIGHT AND SHOULD RESULT IN SOME
CONVECTION ALONG/WEST OF THE MISSISSIPPI RIVER. WILL CONTINUE TO
MONITOR TRENDS REGARDING TSRA POTENTIAL AFT 20Z/15 FOR THE 12Z
TAFS. ..08..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
08/WOLF/WDN
AREA FORECAST DISCUSSION
NWS WICHITA KS
635 PM CDT SAT JUN 16 2012
.AVIATION...00Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
MULTIPLE BOUNDARIES AND WEAK FLOW MADE FOR ANOTHER TOUGH AVIATION
FORECAST. WHILE THUNDERSTORMS CANNOT BE RULED OUT AT ANY SITE...THE
MOSTLY LIKELY SITE WOULD BE KCNU. BASED ON LATEST LAPS 500M CIN/CAPE
ANALYSIS...CAPPING IS NEARLY GONE OVER SOUTHEAST KS/ROUGHLY EAST
OF I-35 WITH CAPE RUNNING BETWEEN 2800-3100 J/KILOGRAM IN THIS AREA.
JUST NOT SURE THERE IS ENOUGH FORCING TO GET STORMS TO GO...AND
WILL KEEP ALL TAFS DRY FOR NOW...AND UPDATE IF/WHEN STORMS START
TO GO. OTHERWISE...SHOULD SEE LIGHT/VARIABLE WINDS OVERNIGHT AND THEN
A INCREASE FROM THE SOUTH DURING THE DAYLIGHT HOURS ON SUN. SOME
CUMULUS ANTICIPATED WITH HEATING ON SUN AS WELL. VFR CONDITIONS
ANTICIPATED EXCEPT NEAR THUNDERSTORMS. -HOWERTON
&&
.PREV DISCUSSION... /ISSUED 521 PM CDT SAT JUN 16 2012/
UPDATE...
THUNDERSTORM INITIATION...OTHER THAN MAYBE A FEW ISOLATED
STORMS...IS STARTING TO LOOK LESS LIKELY DUE TO DECREASING
CONVERGENCE ALONG THE FRONT. ADDITIONALLY...LARGE-SCALE
SUBSIDENCE IN WAKE OF MID-MISSOURI VALLEY MCV...EVIDENCED BY
700-500MB RIDGING OVER KS...IS LIKELY INHIBITING CONVECTIVE
INITIATION AS WELL. GIVEN STRONGLY UNSTABLE CONDITIONS OVER
SOUTHEAST KS DO NOT WANT TO COMPLETELY RULE ANYTHING OUT
YET...BUT IF CURRENT TREND CONTINUES WILL LIKELY BE DECREASING
EVENING POPS.
KLEINSASSER
PREV DISCUSSION... /ISSUED 320 PM CDT SAT JUN 16 2012/
DISCUSSION...
FORECAST CHALLENGES/HIGHLIGHTS FOCUS AROUND THUNDERSTORM CHANCES
LATE THIS AFTERNOON-TONIGHT...WITH THUNDERSTORM CHANCES POSSIBLY
RETURNING BY LATE WEDNESDAY. TEMPERATURES WILL LIKELY BE ABOVE
NORMAL MUCH OF THE NEXT 7 DAYS.
SYNOPSIS...AT THE SURFACE...A WEAK COLD FRONT CURRENTLY STRETCHES
FROM NEAR THE KC METRO...WSW INTO CENTRAL AND WESTERN KS. OLD
OUTFLOW FROM THUNDERSTORM COMPLEX EARLY THIS MORNING HAS NEARLY
WASHED OUT OVER CENTRAL OK. IN THE MID/UPPER LEVELS...AN IMPRESSIVE
MCV (FROM ACTIVITY EARLY THIS MORNING) IS CURRENTLY PROGRESSING
NORTHEAST OVER THE MID-MISSOURI VALLEY...WITH A MUCH SMALLER MCV
(FROM TX PANHANDLE ACTIVITY LAST NIGHT) MEANDERING OVER
NORTHWEST/NORTH-CENTRAL OK.
THIS AFTERNOON-TONIGHT...AIRMASS IS DESTABILIZING NICELY OVER
SOUTHERN/SOUTHEAST KS...ALONG/SOUTH OF THE WEAK COLD FRONT
PROGRESSING SLOWLY SOUTH ACROSS KS. DESPITE SUBSIDENCE IN WAKE OF
MCV TO THE NORTHEAST...THINKING CONTINUED HEATING/CONVERGENCE WILL
ALLOW WIDELY SCATTERED STORMS TO FIRE ALONG THE FRONT BY LATE
AFTERNOON...LIKELY ZIPPERING DOWN INTO SOUTHEAST KS FROM THE
NORTHEAST. HAVE THE HIGHEST CONFIDENCE WITH THIS SCENARIO PER
LATEST HRRR AND OUN WRF MODELS. ISOLATED TO WIDELY SCATTERED
ACTIVITY COULD EVEN BUBBLE FURTHER WSW ALONG THE FRONT INTO SOUTH-
CENTRAL KS...POSSIBLY AIDED BY WEAK NORTHERN OK MCV. ANOTHER
POSSIBLE AREA FOR CONVECTIVE INITIATION IS ALONG WESTERN PORTIONS
OF THE FRONT OVER WEST/SOUTHWEST KS...WITH THIS ACTIVITY POSSIBLY
ROLLING ESE INTO SOUTH-CENTRAL KS THIS EVENING AIDED BY
STRENGTHENING LLJ...ALTHOUGH LOWER INSTABILITY PRECLUDES HIGHER
CONFIDENCE IS THIS AREA. ALL-IN-ALL...AMPLE INSTABILITY & HIGH
PRECIPITABLE WATERS WITH MARGINAL DEEP LAYER SHEAR WILL PROMOTE
STRONG/SEVERE STORMS CAPABLE OF LARGE HAIL (AT LEAST
INITIALLY)...DAMAGING WINDS AND TORRENTIAL RAINFALL...WITH THE
HIGHEST CONFIDENCE AGAIN OVER SOUTHEAST KS. ACTIVITY COULD TEND TO
LINGER OVER FAR SOUTHERN KS WELL INTO THE EVENING...ESPECIALLY IF
SHORT-TERM GUIDANCE IS CORRECT IN STALLING THE BOUNDARY OVER FAR
SOUTHERN KS...BUT CONFIDENCE IS LOW IN THIS SCENARIO LASTING PAST
MIDNIGHT. SEVERE THREAT SHOULD END BY MID/LATE EVENING.
ANTICIPATING CENTRAL KS WILL REMAIN DRY THROUGH THE NIGHT.
SUNDAY...WITH THE POSSIBILITY OF ANOTHER MCV PRODUCED BY OVERNIGHT
CONVECTION...ENDED UP LEAVING SLIGHT CHANCE POPS IN THE FORECAST
GENERALLY EAST OF I-135. HOWEVER...THINK MOST AREAS WILL REMAIN
DRY...AS DEVELOPING STRONG SOUTHERLY FLOW WASHES OUT THE OLD FRONTAL
BOUNDARY BY LATE MORNING. GOOD MIXING AND WARMING LOW-LEVEL
THICKNESSES SHOULD ALLOW TEMPERATURES TO SOAR INTO THE MID-UPPER
90S...WITH NEAR 90 DEGREES OVER SOUTHEAST KS.
MONDAY-TUESDAY...CONTINUED HOT...DRY AND WINDY WEATHER WILL LIKELY
CONTINUE THROUGH MID-WEEK...AS MEDIUM RANGE CONSENSUS SUPPORTS
STRENGTHENING HIGH PLAINS LOW PRESSURE AHEAD OF APPROACHING NORTHERN
ROCKIES SHORTWAVE ENERGY...ALONG WITH BUILDING HEIGHTS/THICKNESS
OVER THE CENTRAL/EASTERN CONUS. HIGHS WELL INTO THE 90S AND LOWS IN
THE 70S APPEAR LIKELY.
WEDNESDAY-WEEKEND...MEDIUM RANGE CONSENSUS SUGGESTS A FRONTAL
BOUNDARY WILL ATTEMPT TO ENCROACH ON THE REGION FROM THE
NORTHWEST...WHICH COULD RESULT IN THUNDERSTORM CHANCES ARRIVING BY
LATE WEDNESDAY...MAINLY OVER THE NORTHERN HALF OF KS. SUSPECT THIS
FRONT WILL HAVE A TOUGH TIME PENETRATING VERY FAR SOUTH...SO OTHER
THAN SOME MODERATING TEMPERATURES MID WEEK...WARMING TEMPERATURES BY
THE WEEKEND APPEAR LIKELY...AS SOUTHERN/WESTERN CONUS RIDGE BUILDS
BACK IN.
KLEINSASSER
AVIATION...18Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
MAIN AVIATION CONCERN WILL BE CONVECTIVE TRENDS THIS AFTERNOON INTO
THE EVENING HOURS.
OVERNIGHT STORMS HAVE LEFT SOME UPPER ENERGY THAT IS SPINNING OVER
NORTHEAST KS. THIS FEATURE HAS PUSHED THE COLD FRONT FURTHER SOUTH
THAN WHAT WAS PREVIOUSLY EXPECTED. THEREFORE THE BETTER PRECIP
CHANCES FOR LATE THIS AFTERNOON AND THIS EVENING WILL BE GENERALLY
EAST OF THE KS TURNPIKE. SO TOOK VCTS OUT EVERYWHERE BUT KICT AND
KCNU WHICH MUCH HIGHER CONFIDENCE IN STORMS OCCURRING AT KCNU.
CONFIDENCE IS HIGH THAT THE REMAINDER OF THE TAF SITES WILL
EXPERIENCE VFR CONDITIONS THROUGH THIS TAF PERIOD.
LAWSON
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 70 94 74 96 / 30 20 10 0
HUTCHINSON 69 95 74 97 / 20 10 10 0
NEWTON 68 93 74 95 / 30 20 10 0
ELDORADO 68 91 73 93 / 30 20 10 0
WINFIELD-KWLD 70 92 73 94 / 40 20 10 0
RUSSELL 66 97 74 99 / 20 10 10 0
GREAT BEND 66 97 74 99 / 20 10 10 0
SALINA 68 95 74 97 / 20 10 10 0
MCPHERSON 68 95 74 97 / 20 20 10 0
COFFEYVILLE 70 90 72 92 / 40 20 10 0
CHANUTE 70 90 72 92 / 40 20 10 0
IOLA 70 90 72 92 / 40 20 10 0
PARSONS-KPPF 70 90 72 92 / 40 20 10 0
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
401 PM EDT FRI JUN 15 2012
.SYNOPSIS...
HIGH PRESSURE WILL SLOWLY BUILD INTO THE REGION FROM THE NORTH
TONIGHT...AND WILL SETTLE OVER THE NORTHEAST AND MID ATLANTIC
STATES THROUGH THE WEEKEND. A WARMING TREND WILL DEVELOP NEXT WEEK
AS HIGH PRESSURE BECOMES CENTERED OFF THE COAST.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
LATEST WX ANALYSIS SHOWING SFC HIGH PRESSURE CENTERED OVER NEW
ENGLAND...NOSING SW DOWN INTO THE DELMARVA...AS SFC LOW PRESSURE IS
SITUATED WELL OFF THE SE US COAST. VISIBLE SATELLITE STILL SHOWING A
FAIR AMOUNT CUMULUS OVER INTERIOR SECTIONS ALTHOUGH CLOUDS ARE GENLY
SCATTERING OUT NOW AND EXPECT MAINLY CLEAR SKIES TOWARDS SUNSET.
SHOULD BE A PRETTY GOOD INVERSION SETTING UP OVERNIGHT W/ MAINLY
CLEAR SKIES AND LIGHT FLOW...THE EXCEPTION BEING ACRS FAR SE VA/NE
NC...WHERE WINDS STAY MORE MIXED AND MODEL SOUNDINGS SUGGEST ANOTHER
ROUND OF STRATOCU AFTER 06-09Z. LOWS PRIMARILY 55-60...EXCEPT 60-65
IN THE FAR SE ZONES.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
OVERALL...NOT A LOT OF CHANGE IN THE PATTERN THROUGH SUNDAY...AS
MID ATLC REMAINS IN BETWEEN AN UPPER TROUGH WELL OFF THE SE
COAST...AND ANOTHER UPPER LEVEL TROUGH MOVING ENE FROM THE UPPER
MIDWEST INTO CENTRAL CANADA. LOW LEVEL FLOW WILL GENLY STAY
EASTERLY THROUGH SUNDAY AS WELL...AND OTHER THAN FAIR WX CU (AND
SOME OCCNL CLOUDS ALONG THE COAST) SKIES WILL AVG OUT MOSTLY
SUNNY. HIGH TEMPS CONTINUE TO RUN BELOW AVG W/ HIGHS MAINLY INTO
THE LWR 80S WELL INLAND AND MID-UPR 70S NEAR THE COAST. NORTHEAST/ONSHORE
FLOW WILL CONTINUE THROUGH THIS PERIOD...HOWEVER WINDS WILL BECOME
LESS BREEZY EACH DAY AS THE PRESSURE GRADIENT RELAXES.
THINGS BEGIN TO CHANGE SOMEWHAT LATE SUN INTO
MON...WITHGFS/NAM/ECMWF ALL SHOWING AN INCREASE IN LOW LEVEL SE
FLOW AND MSTR/CLOUDINESS. HAVE ADDED 20% POPS IN THE PIEDMONT FOR
MONDAY...AS BULK OF UPPER SUPPORT STILL STAYS OFF TO OUR N/W. HIGH
TEMPS RISE SLIGHTLY FOR MON...MAINLY 80-85.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
THE MAIN BAND OF WESTERLIES WILL REMAIN WELL TO THE NORTH OF THE MID
ATLANTIC STATES DURING NEXT WEEK. THIS WILL RESULT IN MAINLY DRY
CONDITIONS FOR THE LONG TERM PERIOD. TEMPERATURES ARE FORECAST TO
WARM TO ABOVE NORMAL READINGS TOWARD MID WEEK.
THE PESKY LOW WELL OFF THE EAST COAST THAT IS EXPECTED TO MEANDER
OVER THE WESTERN ATLANTIC THROUGH THE WEEKEND WILL MOVE WELL OUT TO
SEA BY MID WEEK. THIS WILL ALLOW INCREASING UPPER LEVEL HEIGHTS OVER
THE MID ATLANTIC STATES. A COLD FRONT APPROACHES FROM THE NW ON
FRIDAY AND BASED ON CONSENSUS BETWEEN HPC GUIDE AND 00Z MOS
GUIDE...INCLUDED SLGT CHC TSTMS ON FRIDAY. CANNOT RULE OUT AN
ISOLATED AFTN TSTM TUESDAY THROUGH THURSDAY...ESPECIALLY ON
TUESDAY...BUT CONFIDENCE IS NOT HIGH ENOUGH TO INCLUDE IN THE FCST
AT THIS POINT.
DID SOME BLENDING BETWEEN THE WARMER HPC GUIDE...COOLER MOS GUIDE
AND PREVIOUS FORECAST FOR HIGH TEMPERATURES. TEMPERATURES THUS FAR
THIS SUMMER HAVE GENERALLY BEEN UNDERCUTTING GUIDANCE. FORECAST
HIGHS RANGING FROM THE LOW TO MID 80S NEAR THE COAST TO AROUND 90
WELL INLAND TUESDAY INCREASE TO THE MID TO UPR 80S NEAR THE COAST TO
THE MID 90S WELL INLAND THURSDAY. TEMPERATURES ARE FORECAST TO COOL
SLIGHTLY FRIDAY WITH MORE CLOUD COVER. LOWS IN THE LOW TO MID 60S
TUESDAY MRNG WARM TO AROUND 70 THURSDAY AND FRIDAY MORNINGS.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
VFR AND MOSTLY SUNNY CONDITIONS ACROSS THE REGION AS HIGH PRESSURE
BUILDS IN AND LOW PRESSURE OFFSHORE CONTINUES TO MOVE FARTHER AWAY.
THE HIGH WILL ANCHOR OVER THE AREA THROUGH THE WEEKEND. A FEW
SCATTERED CLOUDS THROUGH THE AFTN BECOMING MOSTLY CLEAR TONIGHT.
NE-E WINDS OVER THE REGION WILL BE GUSTY MAINLY ALONG COASTAL AREAS.
WINDS WILL DIMINISH TONIGHT TO 5-10 KT.
&&
.MARINE...
WINDS HAVE INCREASED OVER THE LOWER BAY AND THE MOUTH OF THE JAMES
RIVER AND HAVE EXTENDED THE SCA FOR THE LOWER JAMES AND THE PORTION
OF THE BAY FROM NEW POINT COMFORT TO LITTLE CREEK THROUGH 10 PM
TONIGHT. THIS EXTENSION WAS MAINLY BASED ON THE RUC WIND FCST THAT
SEEMS TO BE HANDLING THE CURRENT SITUATION THE BEST. SCA REMAINS IN
EFFECT FOR WINDS OVER THE CURRITUCK SOUND THROUGH SATURDAY.
PERSISTENT NE FLOW WILL MAINTAIN SEAS 5 FT OR HIGHER OVER THE
COASTAL WATERS THROUGH EARLY SUNDAY MORNING. SCA CONTINUES IN THE
COASTAL WATERS AND THE MOUTH OF THE CHESAPEAKE THROUGH 10Z SUNDAY.
CURRENT INDICATIONS HAVE SEAS DROP BELOW 5 FT FOR THE MOST PART
SUNDAY.
CONDITIONS DROP BELOW SCA LEVELS SUNDAY OR SUNDAY NIGHT. QUIET
MARINE CONDITIONS ARE ANTICIPATED FOR EARLY NEXT WEEK.
RIP CURRENT RISK REMAINS HIGH FOR AREA BEACHES TODAY DUE TO THE
PERSISTENT NE WINDS AND ABOVE AVERAGE SWELL HEIGHTS. THE FCST FOR
SATURDAY WILL BE ISSUED PRIOR TO 6 PM. SEE CFWAKQ FOR DETAILS.
&&
.TIDES/COASTAL FLOODING...
LATEST MODEL DATA SUGGESTS TIDES REMAINING AT LEAST ONE HALF FOOT
BELOW MINOR FLOODING THRESHOLDS DESPITE RUNNING UP TO 1.5 FT ABOVE
NORMAL. NO STATEMENTS NEEDED GIVEN THESE VALUES ATTM...ALTHOUGH
WILL CONTINUE TO MONITOR.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT SUNDAY FOR ANZ634-650-652-
654-656-658.
SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR ANZ632-
638.
SMALL CRAFT ADVISORY UNTIL 5 PM EDT SATURDAY FOR ANZ633.
&&
$$
SYNOPSIS...LKB
NEAR TERM...LKB
SHORT TERM...LKB
LONG TERM...LSA
AVIATION...JEF
MARINE...LSA
TIDES/COASTAL FLOODING...AKQ
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
110 PM EDT FRI JUN 15 2012
.UPDATE...
ISSUED AT 1010 AM EDT FRI JUN 15 2012
TENDED TO LOWER GOING FCST MAX TEMPS A COUPLE OF DEGREES TO ACCOUNT
FOR FAIRLY WDSPRD CLD COVER/SCT -SHRA IMPACTING THE AREA NOW.
ALTHOUGH THE CLDS ARE LIKELY TO DIMINISH A BIT THRU THE DAY UNDER
RISING H5...MOIST SW FLOW ALF WL TEND TO MAINTAIN ENUF HI CLDS TO
LIMIT THE DIURNAL TEMP RISE. DESPITE THE ABSENCE OF SGNFT DYNAMIC
FORCING...EXPECT AXIS OF HIER MSTR OVER THE CENTRAL ZNS BEST SHOWN
BY THE RUC HIER KINX ANALYSIS/FCST TO BE THE FOCAL POINT FOR
ADDITIONAL SHRA/TS DVLPMNT THRU THE DAY. TENDED TO CUT POPS A BIT
OVER THE SE NEAR BAY OF GREEN BAY/LK MI TO ACCOUNT FOR VERY DRY LLVL
AIR SHOWN ON THE 12Z GRB/APX RAOBS AND LOWER RUC FCST KINX IN THAT
AREA THRU THE DAY.
&&
.SHORT TERM...(TODAY)
ISSUED AT 519 AM EDT FRI JUN 15 2012
THERE IS CURRENTLY A MID LEVEL TROUGH OVER CENTRAL MANITOBA WITH A
SFC LOW BENEATH IT. A SFC TROUGH/COLD FRONT ARE OVER CENTRAL
MN...WITH A WARM FROM CURRENTLY FROM NEAR IRONWOOD TO MENOMINEE.
ISOLATED TO SCATTERED SHOWERS ARE ONGOING ACROSS THE CWA...SOME
DEVELOPING NEAR THE FRONT AND OTHERS FROM DECAYING MCS ACTIVITY FROM
THURSDAY.
EXPECT LITTLE CHANGE IN SHOWER ACTIVITY THIS MORNING AS THE WARM
FRONT CONTINUES TO MOVE NE. THE MID LEVEL TROUGH AND SFC LOW WILL
MOVE TO HUDSON BAY BY 00Z SAT...BRINGING THE COLD FRONT INTO
AREA...BUT IT WILL BE WASHING OUT AS IT COMES ACROSS THE CWA. MODELS
ARE SHOWING GOOD MOISTURE TRANSPORT INTO THE CENTRAL AND WRN CWA
AHEAD OF THE COLD FRONT...WHICH WILL AID SHOWER/THUNDERSTORM
DEVELOPMENT THIS AFTERNOON. THIS IS TRICKY THOUGH AS MODELS SHOW
VERY DRY MID LEVEL AIR MOVING IN FROM THE W LATE THIS
AFTERNOON...WHICH WOULD BE MIXED DOWN TO LOWER LEVELS AND DIMINISH
PRECIP COVERAGE. MODELS VARY ON THE TIMING OF THIS DRY AIR...AND
WITH LITTLE CONFIDENCE IN ONE MODEL OVER ANOTHER...IT IS HARD TO SAY
WHEN THE DRY AIR WILL ARRIVE. CURRENT THINKING IS THAT SHOWERS AND
THUNDERSTORMS WILL DEVELOP /ALTHOUGH COVERAGE CERTAINLY IS IN
QUESTION/ THIS AFTERNOON OVER PARTS OF CENTRAL AND ERN UPPER MI AS
THE FRONT MOVES IN...IN AN AREA WHERE UP TO 1000 J/KG OF CAPE MAY BE
REALIZED. WIND FIELDS WILL BE LIGHT...SO WE SHOULD BE ABLE TO GET
SOME LAKE BREEZE ACTIVITY. ALONG ANY LAKE BREEZES IS WHERE PRECIP
COVERAGE SHOULD BE HIGHEST. THE WEAK WIND FIELDS SHOULD LIMIT
WIDESPREAD SEVERE POTENTIAL...BUT WOULD BE STRONG ENOUGH FOR A
STRONGER STORM OR TWO. GUSTY WINDS WOULD BE THE PRIMARY THREAT WITH
DRIER MID LEVEL AIR. DID NOT GO HIGHER COVERAGE THAN SCATTERED
THUNDERSTORMS THIS AFTERNOON.
PRECIP SHOULD THEN DIMINISH DUE TO A LOSS OF DAYTIME
HEATING/INSTABILITY. ATTENTION THEN TURNS TO PRECIP POSSIBILITY LATE
FRI NIGHT AS A CONVECTIVELY INDUCED SHORTWAVE IS SHOWN HEADING
TOWARD THE CWA BY MODELS...ALTHOUGH MODELS DIFFER WITH TIMING AND
TRACK...WHICH IS EXPECTED IN THIS TYPE OF SITUATION. KEPT ONLY
SLIGHT CHANCE POPS TONIGHT AHEAD OF THE SHORTWAVE...AS MOST MODELS
POINT TO IT ARRIVING AFTER 12Z SAT.
.LONG TERM...(TONIGHT THROUGH THURSDAY)
ISSUED AT 519 AM EDT FRI JUN 15 2012
SATURDAY INTO SATURDAY NIGHT...THE MID/UPPER LEVEL TROUGH FROM SASK
INTO THE NRN PLAINS IS EXPECTED TO MOVE THROUGH NRN MN BEFORE
LIFTING NORTHEAST INTO NRN ONTARIO. THE PREFERRED 12Z/14 ECMWF
REMAINED A BIT STRONGER AND DEEPER WITH THIS FEATURE. THERE MAY BE A
CHANCE OF SHRA/TSRA INTO THE WEST HALF OF UPPER MI SAT MORNING
ASSOCIATED WITH THE WEAK SHRTWVS LIFTING TO THE NE AHEAD OF THE
MAIND TROUGH. CONFIDENCE IS LOW WITH THE TIMING/POSITION OF ANY OF
THESE FEATURES THAT ARE LIKELY TO BE INFLUENCED BY CONVECTION WELL
TO THE SOUTH FROM FRI INTO FRI NIGHT. BY LATE SATURDAY INTO SAT
EVENING...THE COMBINATION OF HEIGHT FALLS AND QVECTOR CONV WITH THE
MAIN TROUGH ALONG WITH LOW LEVEL CONV WITH THE SFC FRONT SHOULD
BRING AN AREA OF SHRA/TSRA THROUGH MUCH OF WEST UPPER MI BY 00Z AND
INTO THE EAST SAT NIGHT. EXPECT THE GREATEST PCPN CHANCES AND
HEAVIEST RAIN OVER THE WEST...CLOSEST TO THE STRONGER DYNAMICS WITH
MID LEVEL TROUGH. SOME STRONGER STORMS WITH SMALL HAIL AND GUSTY
WINDS MAY BE POSSIBLE CAPE VALUES IN THE 1K-2K J/KG RANGE AND 0-6KM
SHEAR OF 30 TO 35 KT.
SUNDAY...DRIER AND SLIGHTLY COOLER WEATHERS WILL MOVE IN SUNDAY
BEHIND THE FRONT WITH WEAK MID LEVEL AND SFC RIDGING TAKING OVER. TEMPS
SHOULD DROP BACK INTO THE UPPER 70S AND LOWER 80S.
SUNDAY NIGHT THROUGH MONDAY NIGHT...ANOTHER MID LEVEVL TROUGH
IS EXPETED TO SHIFT INTO MANITOBA RESUTING IN INCREASED SW FLOW FROM
THE PLAINS INTO THE UPPER GREAT LAKES. AS THE ASSOCIATED SFC TROUGH
MOVES FROM THE NRN PLAINS INTO THE UPPER MS VALLEY STRONG MOISTURE
TRANSPORT (850 MB DEWPOINTS AOA 15C) WILL BRING INCREASING SHRA/TSRA
INTO THE REGION...ESPECIALLY OVER THE WEST HALF. CONSIDERABLE
UNCERTAINTY REMAINS WITH THE DETAILS OF TSRA DEVELOPMENT AT THIS
TIME RANGE. HOWEVER...GIVEN THE STRONGER LOW AND MID LEVEL SHEAR AND
MODERATE INSTABILITY...THERE MAY POTENTIAL FOR STRONGER TO SEVERE
STORMS WITH LOCALLY HEAVY RAIN.
TUE-THU...GRADUAL PATTERN AMPLIFICATION WITH THE WRN CONUS TROUGH
AND RIDGE OVER THE SOUTHEAST MAY BRING A WARM FRONT BACK THROUGH
UPPER MI WITH SHRA/TSRA POTENTIAL THROUGH THE PERIOD AS THE FRONT
LINGERS NEAR THE AREA. TEMPS WILL REMAIN WELL ABOVE NORMAL WITH
HIGHS GENERALLY IN THE 80S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 104 PM EDT FRI JUN 15 2012
SCATTERED SHOWER ACTIVITY STILL POSSIBLE OVER KSAW FOR THE NEXT FEW
HOURS AS RIBBON OF MOISTURE MOVES ACROSS CENTRAL UPPER MI...THOUGH
COLD FRONT AND MAIN LINE OF PRECIP HAS SINCE MOVED EAST OF TAF
SITES. OTHERWISE...EXPECT VFR CONDITIONS AND DRIER AIR FOR MUCH OF
THE TAF PERIOD. LIGHT WINDS AND SOME LINGERING LOW LEVEL MOISTURE
COULD RESULT IN OVERNIGHT FOG DEVELOPMENT ACROSS LAKE
SUPERIOR...THOUGH LIGHT WINDS AT KCMX AND SOUTHERLY FLOW AT KSAW
SHOULD PREVENT FOG FROM ADVECTING ONSHORE. THE NEXT LOW PRESSURE
SYSTEM WILL BEGIN TO IMPACT WESTERN UPPER MI BY TOMORROW
AFTERNOON...SO WENT WITH VCSH AT KIWD SINCE EXACT SET UP AND TIMING
IS STILL UNCERTAIN. DO NOT EXPECT THESE SHOWERS TO MOVE FAR ENOUGH
EAST TO IMPACT KCMX AND KSAW BEFORE 18Z.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 519 AM EDT FRI JUN 15 2012
A COLD FRONT MOVING ACROSS LAKE SUPERIOR TODAY MAY BRING SHOWERS AND
THUNDERSTORMS. WINDS WILL BECOME LESS THAN 15 KTS BY THIS AFTERNOON
AND STAY BELOW 20 KTS THROUGH SUNDAY NIGHT. THERE WILL BE DECENT
CHANCES OF SHOWERS AND THUNDERSTORMS SATURDAY AFTERNOON INTO
SATURDAY NIGHT AS ANOTHER LOW PRESSURE SYSTEM PASSES THROUGH THE
AREA. YET ANOTHER LOW PRESSURE SYSTEMS WILL THEN AFFECT THE AREA
MONDAY AND TUESDAY. SOUTH WINDS OF 20 TO 25 KTS WILL BE POSSIBLE
OVER THE EASTERN HALF MONDAY AFTERNOON AND EVENING.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...KC
SHORT TERM...TITUS
LONG TERM...JLB
AVIATION...JMW
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1012 AM EDT FRI JUN 15 2012
.UPDATE...
ISSUED AT 1010 AM EDT FRI JUN 15 2012
TENDED TO LOWER GOING FCST MAX TEMPS A COUPLE OF DEGREES TO ACCOUNT
FOR FAIRLY WDSPRD CLD COVER/SCT -SHRA IMPACTING THE AREA NOW.
ALTHOUGH THE CLDS ARE LIKELY TO DIMINISH A BIT THRU THE DAY UNDER
RISING H5...MOIST SW FLOW ALF WL TEND TO MAINTAIN ENUF HI CLDS TO
LIMIT THE DIURNAL TEMP RISE. DESPITE THE ABSENCE OF SGNFT DYNAMIC
FORCING...EXPECT AXIS OF HIER MSTR OVER THE CENTRAL ZNS BEST SHOWN
BY THE RUC HIER KINX ANALYSIS/FCST TO BE THE FOCAL POINT FOR
ADDITIONAL SHRA/TS DVLPMNT THRU THE DAY. TENDED TO CUT POPS A BIT
OVER THE SE NEAR BAY OF GREEN BAY/LK MI TO ACCOUNT FOR VERY DRY LLVL
AIR SHOWN ON THE 12Z GRB/APX RAOBS AND LOWER RUC FCST KINX IN THAT
AREA THRU THE DAY.
&&
.SHORT TERM...(TODAY)
ISSUED AT 519 AM EDT FRI JUN 15 2012
THERE IS CURRENTLY A MID LEVEL TROUGH OVER CENTRAL MANITOBA WITH A
SFC LOW BENEATH IT. A SFC TROUGH/COLD FRONT ARE OVER CENTRAL
MN...WITH A WARM FROM CURRENTLY FROM NEAR IRONWOOD TO MENOMINEE.
ISOLATED TO SCATTERED SHOWERS ARE ONGOING ACROSS THE CWA...SOME
DEVELOPING NEAR THE FRONT AND OTHERS FROM DECAYING MCS ACTIVITY FROM
THURSDAY.
EXPECT LITTLE CHANGE IN SHOWER ACTIVITY THIS MORNING AS THE WARM
FRONT CONTINUES TO MOVE NE. THE MID LEVEL TROUGH AND SFC LOW WILL
MOVE TO HUDSON BAY BY 00Z SAT...BRINGING THE COLD FRONT INTO
AREA...BUT IT WILL BE WASHING OUT AS IT COMES ACROSS THE CWA. MODELS
ARE SHOWING GOOD MOISTURE TRANSPORT INTO THE CENTRAL AND WRN CWA
AHEAD OF THE COLD FRONT...WHICH WILL AID SHOWER/THUNDERSTORM
DEVELOPMENT THIS AFTERNOON. THIS IS TRICKY THOUGH AS MODELS SHOW
VERY DRY MID LEVEL AIR MOVING IN FROM THE W LATE THIS
AFTERNOON...WHICH WOULD BE MIXED DOWN TO LOWER LEVELS AND DIMINISH
PRECIP COVERAGE. MODELS VARY ON THE TIMING OF THIS DRY AIR...AND
WITH LITTLE CONFIDENCE IN ONE MODEL OVER ANOTHER...IT IS HARD TO SAY
WHEN THE DRY AIR WILL ARRIVE. CURRENT THINKING IS THAT SHOWERS AND
THUNDERSTORMS WILL DEVELOP /ALTHOUGH COVERAGE CERTAINLY IS IN
QUESTION/ THIS AFTERNOON OVER PARTS OF CENTRAL AND ERN UPPER MI AS
THE FRONT MOVES IN...IN AN AREA WHERE UP TO 1000 J/KG OF CAPE MAY BE
REALIZED. WIND FIELDS WILL BE LIGHT...SO WE SHOULD BE ABLE TO GET
SOME LAKE BREEZE ACTIVITY. ALONG ANY LAKE BREEZES IS WHERE PRECIP
COVERAGE SHOULD BE HIGHEST. THE WEAK WIND FIELDS SHOULD LIMIT
WIDESPREAD SEVERE POTENTIAL...BUT WOULD BE STRONG ENOUGH FOR A
STRONGER STORM OR TWO. GUSTY WINDS WOULD BE THE PRIMARY THREAT WITH
DRIER MID LEVEL AIR. DID NOT GO HIGHER COVERAGE THAN SCATTERED
THUNDERSTORMS THIS AFTERNOON.
PRECIP SHOULD THEN DIMINISH DUE TO A LOSS OF DAYTIME
HEATING/INSTABILITY. ATTENTION THEN TURNS TO PRECIP POSSIBILITY LATE
FRI NIGHT AS A CONVECTIVELY INDUCED SHORTWAVE IS SHOWN HEADING
TOWARD THE CWA BY MODELS...ALTHOUGH MODELS DIFFER WITH TIMING AND
TRACK...WHICH IS EXPECTED IN THIS TYPE OF SITUATION. KEPT ONLY
SLIGHT CHANCE POPS TONIGHT AHEAD OF THE SHORTWAVE...AS MOST MODELS
POINT TO IT ARRIVING AFTER 12Z SAT.
.LONG TERM...(TONIGHT THROUGH THURSDAY)
ISSUED AT 519 AM EDT FRI JUN 15 2012
SATURDAY INTO SATURDAY NIGHT...THE MID/UPPER LEVEL TROUGH FROM SASK
INTO THE NRN PLAINS IS EXPECTED TO MOVE THROUGH NRN MN BEFORE
LIFTING NORTHEAST INTO NRN ONTARIO. THE PREFERRED 12Z/14 ECMWF
REMAINED A BIT STRONGER AND DEEPER WITH THIS FEATURE. THERE MAY BE A
CHANCE OF SHRA/TSRA INTO THE WEST HALF OF UPPER MI SAT MORNING
ASSOCIATED WITH THE WEAK SHRTWVS LIFTING TO THE NE AHEAD OF THE
MAIND TROUGH. CONFIDENCE IS LOW WITH THE TIMING/POSITION OF ANY OF
THESE FEATURES THAT ARE LIKELY TO BE INFLUENCED BY CONVECTION WELL
TO THE SOUTH FROM FRI INTO FRI NIGHT. BY LATE SATURDAY INTO SAT
EVENING...THE COMBINATION OF HEIGHT FALLS AND QVECTOR CONV WITH THE
MAIN TROUGH ALONG WITH LOW LEVEL CONV WITH THE SFC FRONT SHOULD
BRING AN AREA OF SHRA/TSRA THROUGH MUCH OF WEST UPPER MI BY 00Z AND
INTO THE EAST SAT NIGHT. EXPECT THE GREATEST PCPN CHANCES AND
HEAVIEST RAIN OVER THE WEST...CLOSEST TO THE STRONGER DYNAMICS WITH
MID LEVEL TROUGH. SOME STRONGER STORMS WITH SMALL HAIL AND GUSTY
WINDS MAY BE POSSIBLE CAPE VALUES IN THE 1K-2K J/KG RANGE AND 0-6KM
SHEAR OF 30 TO 35 KT.
SUNDAY...DRIER AND SLIGHTLY COOLER WEATHERS WILL MOVE IN SUNDAY
BEHIND THE FRONT WITH WEAK MID LEVEL AND SFC RIDGING TAKING OVER. TEMPS
SHOULD DROP BACK INTO THE UPPER 70S AND LOWER 80S.
SUNDAY NIGHT THROUGH MONDAY NIGHT...ANOTHER MID LEVEVL TROUGH
IS EXPETED TO SHIFT INTO MANITOBA RESUTING IN INCREASED SW FLOW FROM
THE PLAINS INTO THE UPPER GREAT LAKES. AS THE ASSOCIATED SFC TROUGH
MOVES FROM THE NRN PLAINS INTO THE UPPER MS VALLEY STRONG MOISTURE
TRANSPORT (850 MB DEWPOINTS AOA 15C) WILL BRING INCREASING SHRA/TSRA
INTO THE REGION...ESPECIALLY OVER THE WEST HALF. CONSIDERABLE
UNCERTAINTY REMAINS WITH THE DETAILS OF TSRA DEVELOPMENT AT THIS
TIME RANGE. HOWEVER...GIVEN THE STRONGER LOW AND MID LEVEL SHEAR AND
MODERATE INSTABILITY...THERE MAY POTENTIAL FOR STRONGER TO SEVERE
STORMS WITH LOCALLY HEAVY RAIN.
TUE-THU...GRADUAL PATTERN AMPLIFICATION WITH THE WRN CONUS TROUGH
AND RIDGE OVER THE SOUTHEAST MAY BRING A WARM FRONT BACK THROUGH
UPPER MI WITH SHRA/TSRA POTENTIAL THROUGH THE PERIOD AS THE FRONT
LINGERS NEAR THE AREA. TEMPS WILL REMAIN WELL ABOVE NORMAL WITH
HIGHS GENERALLY IN THE 80S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 740 AM EDT FRI JUN 15 2012
MOST UNCERTAINTY AT SAW TODAY AS AFTERNOON SHOWERS/THUNDERSTORMS
WILL BE POSSIBLE...BUT DIFFICULT TO PREDICT. GIVEN LACK OF
CONFIDENCE AND HIGHER PROBABILITY OF LOW COVERAGE...WENT WITH VCSH
FOR THIS AFTERNOON/EVENING AT SAW. A FEW SHOWERS OVER THE AREA RIGHT
NOW WILL GRAZE CMX THIS MORNING...SO ADDED VCSH UNTIL 15Z TODAY. IWD
WILL STAY DRY TODAY AS A COLD FRONT /AND DRIER AIR/ WILL MOVE
THROUGH IN THE NEXT COUPLE OF HOURS.
ASIDE FROM ANY THUNDERSTORM ACTIVITY...CONDITIONS WILL REMAIN VFR
THROUGH THE PERIOD AT ALL SITES. ALSO...THERE COULD BE SOME LAKE
BREEZES TODAY AT THE TAF SITES.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 519 AM EDT FRI JUN 15 2012
A COLD FRONT MOVING ACROSS LAKE SUPERIOR TODAY MAY BRING SHOWERS AND
THUNDERSTORMS. WINDS WILL BECOME LESS THAN 15 KTS BY THIS AFTERNOON
AND STAY BELOW 20 KTS THROUGH SUNDAY NIGHT. THERE WILL BE DECENT
CHANCES OF SHOWERS AND THUNDERSTORMS SATURDAY AFTERNOON INTO
SATURDAY NIGHT AS ANOTHER LOW PRESSURE SYSTEM PASSES THROUGH THE
AREA. YET ANOTHER LOW PRESSURE SYSTEMS WILL THEN AFFECT THE AREA
MONDAY AND TUESDAY. SOUTH WINDS OF 20 TO 25 KTS WILL BE POSSIBLE
OVER THE EASTERN HALF MONDAY AFTERNOON AND EVENING.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...KC
SHORT TERM...TITUS
LONG TERM...JLB
AVIATION...TITUS
MARINE...TITUS
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
634 PM CDT SAT JUN 16 2012
.SHORT TERM...
ISSUED AT 338 PM CDT SAT JUN 16 2012
(TONIGHT)
MAIN FOCUS TONIGHT WILL BE ON THE THREAT OF THUNDERSTORMS. THE
COMBINATION OF GOOD HEATING TODAY AND DEEPER MOISTURE RESULTED IN
VERY UNSTABLE CONDITIONS ACROSS MUCH OF THE CWA BY NOON. ISOLATED
SHOWERS AND THUNDERSTORMS DEVELOPED ACROSS PARTS OF EASTERN MO INTO
SOUTHWEST ILLINOIS AS AN EASTWARD PROPAGATING GRAVITY WAVE
INTERACTED WITH THIS AIR MASS PROVIDING WEAK ASCENT. COVERAGE OF
THESE STORMS HAS LARGELY DIMINISHED AS THE ASCENT HAS WEAKENED WITH
THE PASSAGE OF THE WAVE AND ALSO IN RESPONSE TO LESSER INSTABILITY
RESULTING FROM A MIXING IN THE DEEPENING BOUNDARY LAYER. THE
ATTENTION FOR THE REMAINDER OF THE AFTERNOON AND TONIGHT WILL TURN
TO THE REMNANT MCV NOW CENTERED IN NW MO AND APPROACHING COLD FRONT.
ENHANCED MESOSCALE LIFT ASSOCIATED WITH THE MCV HAS PRODUCED A GOOD
THUNDERSTORM CLUSTER ALONG THE SW IA/NW MO BORDER WITH MORE ISOLATED
COVERAGE SOUTHWARD. THIS FEATURE IS FORECAST TO TRACK EASTWARD THIS
EVENING AHEAD OF THE ENCROACHING COLD FRONT AND INTO NRN IL BY
MIDNIGHT. LIFT ASSOCIATED WITH IT AND A VEERING SWLY LLJ OF 25-35
KTS IS EXPECTED TO PROVIDE CONTINUED SUPPORT FOR THUNDERSTORMS
ACROSS NORTHERN MO INTO WEST CENTRAL IL THIS EVENING. THE MAIN
QUESTION IS HOW FAR SOUTH THE THUNDERSTORMS WILL MOVE. VIRTUALLY ALL
THE MODEL QPFS HAVE A GOOD SWATH OF MEASURABLE PRECIPITATION
TRANSLATING SOUTHWARD THROUGH THE NIGHT TO AT LEAST I-70. THE
CONVECTION ALLOWING MODELS AND ESPECIALLY RECENT RUNS OF THE HRRR
SUGGEST THERE WILL BE ADDITIONAL CONVECTION DEVELOPING FROM THE
AGITATED CU FIELD NOW EXTENDING FROM CHILLICOTHE TOWARDS EMPORIA KS
AND THIS ALONG WITH THE CLUSTER FURTHER NORTH WILL ORGANIZE INTO A
MCS THAT TRACKS SEWD. WHETHER IT IS A COMBINATION OF CONVECTION
ASSOCIATED WITH THE MCV AND CONVECTIVE OUTFLOWS OR LIFT AHEAD OF THE
FRONT ITSELF...IT IS HARD TO ARGUE AGAINST BRINGING LIKELY POPS DOWN
TO AROUND I-70.
GLASS
&&
.LONG TERM...
ISSUED AT 306 PM CDT SAT JUN 16 2012
(SUNDAY THROUGH SATURDAY)
SUNDAY`S WEATHER WILL DEPEND HEAVILY ON HOW CONVECTION DEVELOPS AND
MOVES TONIGHT AND HOW FAR SOUTH THE FRONT GETS ON SUNDAY. CURRENT
THINKING IS THAT THE FRONT WILL WASH OUT NEAR OR JUST NORTH OF THE
I-70 CORRIDOR. NAM/GFS/LOCAL WRF/SREF HAVE SOME EXTENT OF LINGERING
PRECIP DURING THE MORNING HOURS DOWN ACROSS SOUTHEAST MISSOURI AND
SOUTHERN ILLINOIS. THIS DOESN`T SEEM UNREASONABLE GIVEN THE
REMAINING SHORTWAVE ENERGY RIPPLING ALONG ALOFT DURING THE MORNING
AND THE RESIDUAL MOISTURE CONVERGENCE ON THE LOW LEVEL JET. HOWEVER
DISCRETE CONVECTIVE MODELS SUCH AS THE HRRR AND 4KM NCEP WRF LOOK
PRETTY DRY AFTER THE MCS LOSES STEAM LATE TONIGHT...THEN THE 4KM WRF
FIRES PRECIP DOWN OVER THE OZARKS DURING THE LATE AFTERNOON.
REGARDLESS...THINK THE BEST I CAN DO IS CHANCE POPS FOR
SUNDAY...UNSURE OF TIMING OR COVERAGE...BUT THERE IS CERTAINLY THE
POTENTIAL FOR PRECIP. SUNDAY NIGHT THE LOW LEVEL JET RAMPS UP AND
THE FRONT MOVES BACK NORTH. MODELS ARE SHOWING LIGHT QPF ON THE
NOSE OF THE WARM AIR ON AN AREA OF DECENT 850MB MOISTURE CONVERGENCE
OVER NORTHEAST MO/WEST CENTRAL IL DURING THE EVENING...SO HAVE
BUMPED UP TO CHANCE IN THOSE AREAS.
CONTINUING HOT AND DRY FORECAST FOR MONDAY AT LEAST THROUGH
WEDNESDAY. STRONG UPPER LEVEL HIGH BUILDS BACK INTO THE TENNESSEE
VALLEY WHICH SHOULD KEEP US STUCK IN SOUTHWEST FLOW. LOW TO MID 90S
DURING THE DAY AND LOW TO MID 70S AT NIGHT. SHOULD FEEL LIKE
SUMMER. MEDIUM RANGE MODELS ARE ADVERTISING A PATTERN SHIFT TOWARD
THE END OF THE WEEK WITH THE RIDGE TO OUR EAST BREAKING DOWN AND A
FROPA LATE THURSDAY OR FRIDAY. SHOULD BRING US COOLER TEMPERATURES
INTO NEXT WEEKEND AND A CHANCE FOR RAIN THURSDAY NIGHT AND FRIDAY.
CARNEY
&&
.AVIATION...
ISSUED AT 635 PM CDT SAT JUN 16 2012
A SWATH OF LOOSELY ORGANIZED THUNDERSTORMS HAS DEVELOPED THROUGH
THE AFTERNOON AND STRETCHED FROM NORTHEAST MISSOURI TO JUST WEST
OF COLUMBIA TO SEDALIA AT TAF ISSUANCE TIME. OVERALL THE CONSENSUS
OF THE GUIDANCE IS THAT THIS SYSTEM WILL MOVE EAST THROUGH THE
EVENING CONTAINING EMBEDDED STRONGER CELLS. THE MOST INTENSE
STORMS SHOULD DROP VSBYS BLO 3SM WITH CIGS BLO 3000 FT AND WILL
HAVE SOME GUSTY WINDS. SHOWERS AND THUNDERSTORMS WILL POTENTIALLY
IMPACT KUIN THROUGH 02-03Z AND KCOU THROUGH 03-04Z. IF THIS
ACTIVITY CAN MAINTAIN ITS CURRENT STATUS IT SHOULD MOVE INTO THE
ST LOUIS AREA IN THE 03-04Z TIME FRAME BUT THERE IS SOME
UNCERTAINTY IN THE TIMING...COVERAGE AND INTENSITY BY THIS TIME.
THE NEW TAF HAS THE POTENTIAL FOR STORMS IN THE ST LOUIS AREA
EARLIER THAN PREVIOUSLY BUT IS CONSERVATIVE ON THE INTENSITY. ALL
OF THIS ACTIVITY COULD DROP SOUTH/SOUTHEAST OF ST LOUIS BY 06-07Z
WITH DRY CONDITIONS AND VFR THEREAFTER. WINDS ARE SOMEWHAT
PROBLEMATIC WITH A GENERAL SHIFT TO MORE WESTERLY AFTER THE
PASSAGE OF THE STORMS AND THEIR BOUNDARY. A COLD FRONT WELL TO THE
NORTH IS EXPECTED TO MOVE THROUGH KUIN OVERNIGHT AND STALL THEN
LIFT BACK NORTHWARD ON SUNDAY MORNING. A MIX OF SCATTERED-BROKEN
CU AND SOME MID/HI CLOUDS ARE EXPECTED ON SUNDAY...WHILE PRECIPITATION
PROBABILITY AT ANY TAF SITE IS TOO LOW TO MENTION.
SPECIFICS FOR KSTL...
WATCHING LOOSELY ORGANIZED SWATH OF THUNDERSTORMS EXTENDING FROM
NORTHEAST MISSOURI INTO WEST CENTRAL MO. IF THIS ACTIVITY CAN
MAINTAIN ITS CURRENT STATUS IT SHOULD COULD IMPACT THE TERMINAL IN
THE 03-04Z TIME FRAME BUT THERE IS SOME UNCERTAINTY IN THE
TIMING...COVERAGE AND INTENSITY BY THIS TIME. THE NEW TAF HAS THE
POTENTIAL FOR STORMS EARLIER THAN PREVIOUSLY BUT IS CONSERVATIVE
ON THE INTENSITY. ALL OF THIS ACTIVITY COULD DROP SOUTH/SOUTHEAST
OF ST LOUIS BY 06-07Z WITH DRY CONDITIONS AND VFR THEREAFTER.
WINDS ARE SOMEWHAT PROBLEMATIC WITH A GENERAL SHIFT TO MORE
WESTERLY AFTER THE PASSAGE OF THE STORMS AND THEIR BOUNDARY. A
MIX OF SCATTERED-BROKEN CU AND SOME MID/HI CLOUDS ARE EXPECTED ON
SUNDAY...WHILE PRECIPITATION PROBABILITY AT ANY TAF SITE IS TOO
LOW TO MENTION.
GLASS
&&
.PRELIMINARY POINT TEMPS/POPS...
ST LOUIS 72 88 73 95 / 60 40 30 5
QUINCY 68 87 70 93 / 70 30 30 5
COLUMBIA 69 89 70 93 / 70 40 20 5
JEFFERSON CITY 70 90 71 93 / 60 40 10 5
SALEM 71 86 71 92 / 50 50 20 5
FARMINGTON 70 88 68 91 / 40 40 10 5
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1225 AM CDT Fri Jun 15 2012
...UPDATED AVIATION DISCUSSION...
.DISCUSSION...
Short Term (Tonight through Saturday Night)...
Gusty southeast winds have maintained rather dry conditions across
the area this afternoon, while abundant sunshine has pushed
temperatures into the middle and upper 80s. Meanwhile, quality
moisture continues to stream north through the Plains, denoted by an
increasing Cu field from Omaha-Topeka-Chanute westward. Cloud cover
along an advancing cold front was enhancing differential heating
from north of Omaha to Hastings, and continued afternoon heating
coupled with increasing moisture is expected to lead to thunderstorm
initiation within the next couple of hours. The evolution of this
activity leads to considerable uncertainly locally as we head into
the overnight hours.
At face value, the combination of strong instability, frontal
convergence and a weak mid level impulse leads to high confidence of
thunderstorm initiation across the Mid Missouri Valley. As has been
the case of late, deep layer shear is marginally supportive of
multi-cell clusters. However, it should be noted that the bulk of
the deep layer shear (20-30 kts) is focused mainly in the lowest
3-4km. Historically, these high CAPE and weak, low tropospheric
shear cases have been overlooked and can often manifest themselves
as long-lived organized MCS events. The NAM has been suggesting this
in the mass fields for a number of runs now, and recent HRRR and
other convection allowing output also side with this notion. Low
level shear vectors and moisture flux vectors would suggest an
overall SE momentum of any organized system(s), with an eastern
limit bounded by the dry air circulating the high to our east. With
that said, feel that increasing POPs is warranted both numerically
and spatially across western MO and eastern KS for tonight. Severe
weather, primarily in the form of wind potential, will be dictated
by any upscale growth of the system and the maintenance of
downstream instability into the late evening hours. This is somewhat
more questionable, but the derecho that ran from srn MO to the Gulf
coast back on Monday occurred in a far less suitable environment.
Depending on any remnant MCV and/or surface outflow boundary,
differential heating could again yield scattered thunderstorms again
tomorrow afternoon, with several larger scale perturbations
emanating from the central Rockies providing greater chances
Saturday and Sunday. Precipitation/cloud cover will ultimately drive
max/min temperature potential, so have opted to stay the course with
mid-upper 80s for highs and 65-70 for lows for the bulk of the CWA
as a hedge toward persistence (just above climo).
Bookbinder
Medium Range (Sunday through Thursday)...
Tail end of the weekend will arrive with a frontal boundary sagging
south into eastern Kansas and northern Missouri, pushed into our
region by one of many shortwaves moving through the northern stream.
GFS and ECMWF have converged some over the past couple of runs
towards a common solution which pushes the late weekend frontal
boundary south into Missouri during the day Sunday. However, as the
front settles into Missouri the parent shortwave will be exiting the
region through the Upper Great Lakes, indicating that the southerly
push on the front will fade quickly. This presents the likely
scenario for Sunday something like this; decaying thunderstorms may
still be kicking around parts of eastern Kansas and Missouri after
sunrise Sunday with it likely that any morning activity will either
shift east out of the area, or fade away by the mid to late morning
hours. This, however, leaves the potential for afternoon recovery of
instability in the vicinity of the frontal boundary that should be
wallowing around the northern half of Missouri. Of course convective
debris may complicate this, but in general this has lent some
confidence to the idea that rain will make an appearance across
parts of the forecast area Sunday, whether it`s from the morning
activity (more likely) or afternoon initiation (a little less
likely). Have avoided pushing up any of the POPs for Sunday beyond
the chance category as the persistently advertised surface high,
which will be stretched across the eastern CONUS through the Gulf
Coast, will likely impede the moisture return from the Gulf some.
After Sunday, a very broad trough is advertised to have moved into
the western CONUS, this will result in a slightly more southwest
orientation to the flow, likely keeping temperatures above normal
through the middle of the work week. As this occurs, focus for any
potential precipitation will shift north, closer to the storms track
of the westerlies. Have damped down any mention of POPs from Monday
through the day Wednesday as a result. Wednesday night into Thursday
the broad west CONUS trough should be starting to traverse the upper
half of the Plains States, so have kept chance POPs in for Wednesday
night and Thursday as another frontal boundary settles south.
Cutter
&&
.AVIATION...
For the 06Z TAFs, the biggest concern is for thunderstorm activity
into the terminals in the next 3-6 hours. A decaying convective
system was tracking across eastern Kansas very slowly and remnants
from this system should reach the terminals around 7-8Z. Confidence
is decreasing that any widespread thunderstorm activity will be seen
and certainly the chances for any severe convection are quite low.
But the terminals should still see rain and an occasional rumble of
thunder as the trailing stratiform rain shield moves over. So have
opted for a -RA VCTS group to account for this. Cigs should stay on
the low end of VFR and there may be some minor reductions in
visibility to around 4 or 5 miles. This activity will continue to
diminish through the morning hours but the effects will be felt
through much of the day in the form of cloud cover that may really
inhibit further development this afternoon. Have opted to just
include VCTS for late this afternoon into the evening hours but
confidence is not very high.
CDB
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
WFO EAX
AREA FORECAST DISCUSSION
NWS GLASGOW MT
929 AM MDT FRI JUN 15 2012
.SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH SUNDAY...
MORNING UPDATE. RADAR LOOKS IMPRESSIVE ACROSS THE WESTERN PORTIONS
OF THE COUNTY WARNING AREA BUT REPORTS INDICATE A FEW SPRINKLES AT
MOST. KEEPING AN EYE ON THE SOUTHEAST CORNER OF THE CWA AS
CONVECTION MOVED INTO THAT AREA FROM THE SSE LAST NIGHT. DEWPOINTS
IN THE DAKOTAS ARE IN THE 50S AND PUSHING INTO EAST CENTRAL
MONTANA. A TROF IS SEEN ON THE RADAR AND SATELLITE PUSHING ACROSS
CENTRAL MONTANA THIS MORNING. LOW PRESSURE IS CENTERED IN THE
MALTA AREA AS OF 930 AM THIS MORNING. THAT TROF WILL MOVE SLOWLY
THROUGH OUR CWA TODAY AND ALLOW FOR SOME CONVECTION TO POP TO THE
EAST OF THE TROF AFTER THE NOON TO 2 PM TIME FRAME. AREAS EAST OF
HIGHWAY 24 AND HIGHWAY 13 WILL HAVE THE BEST CHANCE OF ANY
PRECIPITATION ACCUMULATIONS. GIVEN THE INSTABILITY AND MOISTURE
AVAILABILITY IN OUR EXTREME SOUTHEAST...WE ARE IN A SLIGHT RISK OF
SEVERE STORMS IN THAT AREA. BUT LOOKING AT THIS MORNINGS UA
SOUNDINGS AND THE FORECASTS...LOOKS TO BE FAVORABLE FOR MORE MULTICELLULAR
TYPES OF SHOWERS AND THUNDERSTORMS. TERRY TO GLENDIVE TO WIBAUX AND
SOUTHEAST MAY SEE SOME SMALL HAIL AND GUSTY WINDS TO 40 OR 50
MPH AS STORMS MOVE THROUGH LATER THIS AFTERNOON. FRANSEN
AN UPPER WAVE OVER SOUTHEAST BRITISH COLUMBIA EARLY THIS MORNING
WILL PUSH EASTWARD ACROSS THE HIGH PRAIRIES NUDGING DOWN INTO
MONTANA TODAY AS IT MOVES THROUGH.
THE HRRR IS OVER AGGRESSIVE ON QPF AND FORECAST REFLECTIVITY FIELDS
EARLY ON IN THE LATEST RUN. COMPARING THE TFX AND SCHULER
RADARS...THERE IS BETTER SHOWER COVERAGE NORTH OF MEDICINE HAT
TOWARDS KINDERSLEY THIS MORNING. THE NAM12 HAS THE BEST
INITIALIZATION... HOWEVER IT ISN/T WITHOUT IT/S DEFECTS EITHER
WITH PRECIPITATION COVERAGE THIS MORNING.
THE SURFACE FRONT LIES FROM NEAR KINDERSLEY BACK TO SPOKANE...AND
THE SHOWER ACTIVITY SEEMS MOSTLY POST FRONTAL. THE NAM FITS THE
PATTERN WITH MOST OF IT/S QPF POST FRONTAL... OTHER THAN AN
ISOLATED AREA NEAR SWIFT CURRENT AT THE 12Z 6HR TIME STEP. THE
FRONT IS BEING FORCED BY THE UPPER WAVE EASTWARD AND DOESN/T MAKE
MUCH PROGRESS SOUTH. BY 18Z OR MID DAY THE FRONT ENTERS INTO
PHILLIPS COUNTY WITH THE PRE-FRONTAL TROUGH OVER THE EASTERN ZONES
WHERE THE NAM FIRES SOME CONVECTION ALONG IT. BY 00Z THE FRONT
SHOULD BE RIGHT ALONG THE ND/MT BORDER WITH THE UPPER TROUGH
MOVING THROUGH THE CENTRAL ZONES. PLAYED HIGH POPS TODAY OVER THE
EASTERN THIRD OF THE ZONES ALONG THE PRE-FRONTAL TROUGH AND ENDED
CONVECTIVE ACTIVITY WITH THE UPPER TROUGH AS IT MOVES THROUGH. THE
AREA SOUTH OF I-94 IS OUTLOOKED IN SPC DAY 1 FOR SLIGHT RISK. FOR
NOW FOR THE LATE AFTERNOON AND EARLY EVENING HOURS I WILL MENTIONS GUSTY
WINDS AND SMALL HAIL. NOT TOO EXCITED ABOUT SEVERE CONVECTIVE
ACTIVITY FOR THE REGION WITH THIS SYSTEM. PLUS...GIVEN THE REDUCED
CONFIDENCE WITH THE POOR MODEL HANDLING OF THE SITUATION..I WILL
NOT GET TOO OVER-EXCITED AT THIS TIME.
FOR TONIGHT AND SATURDAY... UPPER TROUGH SWINGS EAST DRYING UP THE
WEATHER FOR NORTHEAST MONTANA. WINDS SHOULD REMAIN BELOW LAKE
WIND LEVELS MAKING FOR A NICE LAKE SATURDAY IN QUIET AWHILE FOR
FORT PECK LAKE.
SUNDAY BRINGS ANOTHER UPPER TROUGH AND SURFACE FRONT FOR ANOTHER
ROUND OF CONVECTION FOR THE REGION. PROTON
.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY...
THE LONG TERM FORECAST PERIOD BEGINS AS A VERY TIGHTLY PACKED
UPPER LEVEL PRESSURE GRADIENT PULLS A NEARLY ZONAL FLOW THROUGH
THE NORTHERN ROCKIES WITH MULTIPLE VERY SUBTLE EMBEDDED SHORT WAVE
DISTURBANCES SETTING OFF REPEATED ROUNDS OF SHOWERS AND THUNDERSTORMS.
BY MONDAY MORNING...THAT ZONAL FLOW GIVES WAY TO A VERY LARGE
SCALE BROAD UPPER LEVEL TROUGH WHICH SPREADS FROM THE PACIFIC
NORTHWEST TO MINNESOTA WITH THE BASE OF THE TROUGH REACHING AS FAR
SOUTH AS NORTHERN UTAH. THIS WILL BE THE MAIN WEATHER PATTERN TO
AFFECT OUR CWA THROUGHOUT MOST OF THE WEEK. THE TWO MAIN STORM
SYSTEMS WHICH WILL PASS THROUGH WITH THIS BROAD TROUGH WILL BE
SOMETIME TUESDAY THROUGH THURSDAY AS SHOWN BY THE LARGE SCALE
FORCING FOR ASCENT BY THE GFS...BUT MAY ONLY AFFECT PORTIONS OF
OUR CWA.
THURSDAY NIGHT AND BEYOND...WEAK UPPER LEVEL RIDGING RETURNS TO
THE NORTHERN ROCKIES BRINGING A DRIER WEATHER TREND TO NORTHEAST
MONTANA WITH SOME SLIGHT DISAGREEMENT BETWEEN EXTENDED MODEL
SOLUTIONS AS ANOTHER UPPER LEVEL LOW CENTER LINGERS OF THE BRITISH
COLUMBIAN COASTLINE. BMICKELSON
&&
.AVIATION...
VFR CONDITIONS THROUGH SATURDAY MORNING. LIGHT EAST-SOUTHEAST
WINDS WILL SHIFT FROM THE WEST-NORTHWEST AS AN UPPER LEVEL DISTURBANCE
AND SURFACE FRONT PUSHES THROUGH EASTERN MONTANA THIS AFTERNOON.
WIND SPEEDS ARE EXPECTED TO BE 10 TO 20 KTS WITH A FEW GUSTS UP TO
25 KTS WITH THE FRONTAL PASSAGE.
SHOWERS AND THUNDERSTORMS WILL ACCOMPANY THIS FRONT...
WHICH MAY RESULT IN VICINITY SHOWERS AND THUNDERSTORM FOR ALL
TERMINALS IN NORTHEAST MONTANA THIS AFTERNOON... AND KSDY AND KGDV
THROUGH THE EVENING HOURS. BRIEF MVFR VISIBILITY MAY OCCUR SHOULD
A THUNDERSTORM MOVE DIRECTLY OVER ANY OF THE TAF SITES. AES
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS BILLINGS MT
332 AM MDT FRI JUN 15 2012
.SHORT TERM...VALID FOR TDY AND SAT...
A SHORT WAVE TROUGH IN PROGRESSIVE 500-HPA FLOW WILL BRING CHANCES
OF THUNDERSTORMS TO THE AREA THROUGH THIS EVENING...BUT A WARM AND
DRY SAT LOOKS TO BE IN STORE BEHIND THIS WAVE. CONVECTIVE COVERAGE
THROUGH THIS EVENING WILL BE GREATEST IN SOUTHEASTERN MT OUT AHEAD
OF A COLD FRONT...BUT THE FORECAST IS SOMEWHAT UNCERTAIN THANKS TO
QUESTIONS ABOUT THE DEGREE OF MOISTURE RETURN AND THE COVERAGE AND
EFFECTS OF EARLY-DAY CONVECTION.
EARLY THIS MORNING...A 40 KT 850-HPA LOW-LEVEL JET IS CONTRIBUTING
TO FORMATION OF ELEVATED CONVECTION OVER FAR SOUTHEASTERN MT BASED
ON 09 UTC INFRARED SATELLITE IMAGERY. WE HAVE CHANCE POPS IN PLACE
IN THAT AREA THROUGH 18 UTC TO COVER THIS DEVELOPMENT...BUT WE ARE
NOT SURE HOW ROBUST OR WIDESPREAD THE CONVECTION WILL BE. FOR THAT
REASON...WE ACTUALLY LOWERED POPS IN SOUTHEASTERN MT BEFORE 18 UTC
COMPARED TO PREVIOUS FORECASTS. THE UNCERTAINTY STEMS FROM DELAYED
OR REDUCED MOISTURE ADVECTION ON THE HIGH PLAINS THIS MORNING WITH
RESIDUAL EFFECTS OF THE EXPANSIVE CONVECTION LAST EVENING WREAKING
SOME HAVOC ON THE MOISTURE FIELD. MOST OF THE 00 UTC MODELS CALLED
FOR SURFACE DEWPOINTS IN THE MID 50S F BY THIS TIME ACROSS WESTERN
NEB...WHERE THEY ARE ACTUALLY ONLY IN THE MID TO UPPER 40S F. THIS
SAME SCENARIO IS SHOWN BY THE SATELLITE-DERIVED PRECIPITABLE WATER
VALUES UPSTREAM OF SOUTHEASTERN MT...WHICH ARE 75 PERCENT OR SO OF
WHAT MOST MODELS HAD SIMULATED BY 09 UTC. IN ALL LIKELIHOOD...THIS
SCENARIO WILL STILL GENERATE SOME SHOWERS OR STORMS...BUT THEY ARE
NOT APT TO BE AS WIDESPREAD OR LONG-LASTING AS THOUGHT PREVIOUSLY.
THE LAST FEW HRRR RUNS AND THE 06 UTC NAM REFLECT THIS IDEA WELL.
THIS AFTERNOON AND EVENING...MLCAPE OF 500 TO 1000 J/KG LOOKS LIKE
IT IS ACHIEVABLE AHEAD OF THE COLD FRONT IN SOUTHEASTERN MT. GIVEN
40-50 KT OF 0-6 KM BULK WIND SHEAR WITH A VEERING WIND PROFILE...A
RISK OF SEVERE HAIL OR WIND WILL EXIST. INTERESTINGLY...IF MORNING
CONVECTION IS NOT ESPECIALLY WIDESPREAD...THAT COULD ACTUALLY HELP
OUT THE PROSPECT OF SURFACE-BASED STORMS AFTER 18 UTC BECAUSE MORE
BOUNDARY LAYER DESTABILIZATION COULD THEN OCCUR. HOWEVER...CAPE IS
NOT LIKELY TO BE HIGH ENOUGH FOR MORE THAN A FEW SEVERE EVENTS. IT
ALSO LOOKS LIKE SOME WEAKER....HIGH-BASED CONVECTION WILL FORM OUT
AHEAD OF THE 500-HPA SHORT WAVE IN SOUTH CENTRAL MT...LIKELY FIRST
ACROSS THE HIGHER TERRAIN. THE 00 UTC 4 KM WRF-NMM AND EVEN THE 05
UTC HRRR AND 06 UTC NAM SUPPORT THIS IDEA...WHICH IS SUPPORTIVE OF
OUR CHANCE POPS IN PLACES LIKE BILLINGS...EVEN IN THE POST-FRONTAL
ENVIRONMENT WHERE BUOYANCY WILL BE LIMITED.
TONIGHT...ANY CONVECTION SHOULD BE RAPIDLY EXITING THE AREA BEFORE
06 UTC...THOUGH WE WILL MAINTAIN SOME CHANCES AROUND BAKER THROUGH
THE NIGHT OUT OF RESPECT TO THE PASSAGE OF THE 500-HPA TROUGH.
SAT...A DRY WEST-NORTHWEST FLOW ALOFT WILL BE IN PLACE WITH MIXING
TO AROUND 700 HPA EXPECTED. HIGHS ACROSS MOST OF THE PLAINS SHOULD
EASILY EXCEED 80 F...AND IF THE 00 UTC GFS IS CORRECT WITH THERMAL
PROFILES...OUR FORECAST MAY NOT BE QUITE WARM ENOUGH. SCHULTZ
.LONG TERM...VALID FOR SUN...MON...TUE...WED...THU...
THE EXTENDED FORECAST SEES A GENERALLY PROGRESSIVE FLOW WITHIN
AN OVERALL CYCLONIC PATTERN THE FIRST HALF OF THE WEEK...
TRANSITIONING TO A MORE WESTERLY FLOW OR PERHAPS ANTI CYCLONIC
FLOW LATER IN THE WEEK. HOWEVER...THE MODELS HAVE SOME SIGNIFICANT
CONFLICTS IN TIMING OF TROUGHS AND RIDGES...PARTICULARLY AT MID
WEEK. DESPITE THIS...MOS GUIDANCE FOR THE ECMWF AND GFS ARE NOT
THAT FAR OFF ON HIGHS AND LOWS...WHICH MAY BE MORE LUCK THAN
METEOROLOGY GIVEN DIFFERENCES. AT ANY RATE...CONFIDENCE SLIGHTLY
ABOVE AVERAGE FOR TEMPERATURES...AND SLIGHTLY BELOW AVERAGE FOR
TIMING AND PLACEMENT OF POPS. THE BIGGEST QUESTION MARK IS AROUND
THURSDAY WHEN THE ECMWF HAS A LOW AMPLITUDE RIDGE OVER OUR
FORECAST AREA AND THE GFS CONTINUES TO FORCE A SHORT WAVE TROUGH
DOWN OVER OUR REGION. THOUGH ECMWF LOOKS BEST AT THIS POINT...WILL
NOT RULE OUT THE CHANCE THE GFS IS PICKING UP A MINOR WAVE AND
JUST AMPLIFYING IT TOO MUCH. SO WILL LEAVE IN SOME LOW POPS FOR
THURSDAY. BT
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL THE REST OF THE NIGHT AND INTO FRIDAY
MORNING. THERE IS A CHANCE OF A FEW SHOWERS AND POSSIBLY ISOLATED
LIGHTNING BY LATE MORNING EAST AND SOUTH OF KMLS. THE CHANCE OF
THUNDERSTORMS WILL INCREASE FROM KMLS SOUTH AND EAST BY MID
AFTERNOON WITH ISOLATED HAIL AND SEVERE WIND GUSTS POSSIBLE NEAR
THE MONTANA/DAKOTA BORDERS. A COOL FRONT WILL BE MOVING THROUGH
THE FORECAST AREA THIS MORNING THROUGH THE AFTERNOON. THIS WILL
CAUSE A SHARP CHANGE IN WIND DIRECTIONS TO THE NW. PLEASE SEE
TAFS FOR MORE DETAIL ON FRONTAL PASSAGE TIMING. BT
&&
.PRELIMINARY POINT TEMP/POPS...
TDY SAT SUN MON TUE WED THU
-------------------------------------------------------
BIL 078 050/084 060/084 055/075 052/070 051/070 051/078
3/T 20/U 02/T 22/T 23/T 33/T 21/U
LVM 075 040/083 051/078 047/071 045/063 041/067 042/079
2/T 10/U 02/T 22/T 34/T 43/T 21/B
HDN 080 049/084 057/085 058/078 051/073 050/073 051/081
3/T 20/U 02/T 22/T 23/T 33/T 21/B
MLS 080 053/083 061/084 058/077 055/073 054/072 051/077
3/T 21/B 02/T 22/T 23/T 43/T 21/B
4BQ 081 053/082 058/085 058/077 053/074 052/071 050/075
4/T 31/B 02/T 22/T 23/T 33/T 22/T
BHK 077 053/078 057/083 056/074 053/074 052/069 049/076
6/T 61/U 02/T 32/T 23/T 43/T 22/T
SHR 078 048/081 054/083 054/073 048/073 047/069 047/076
3/T 21/B 01/B 22/T 22/T 33/T 22/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS GLASGOW MT
329 AM MDT FRI JUN 15 2012
.SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH SUNDAY...
AN UPPER WAVE OVER SOUTHEAST BRITISH COLUMBIA EARLY THIS MORNING
WILL PUSH EASTWARD ACROSS THE HIGH PRAIRIES NUDGING DOWN INTO
MONTANA TODAY AS IT MOVES THROUGH.
THE HRRR IS OVER AGGRESSIVE ON QPF AND FORECAST REFLECTIVITY FIELDS
EARLY ON IN THE LATEST RUN. COMPARING THE TFX AND SCHULER
RADARS...THERE IS BETTER SHOWER COVERAGE NORTH OF MEDICINE HAT
TOWARDS KINDERSLEY THIS MORNING. THE NAM12 HAS THE BEST
INITIALIZATION... HOWEVER IT ISN/T WITHOUT IT/S DEFECTS EITHER
WITH PRECIPITATION COVERAGE THIS MORNING.
THE SURFACE FRONT LIES FROM NEAR KINDERSLEY BACK TO SPOKANE...AND
THE SHOWER ACTIVITY SEEMS MOSTLY POST FRONTAL. THE NAM FITS THE
PATTERN WITH MOST OF IT/S QPF POST FRONTAL... OTHER THAN AN
ISOLATED AREA NEAR SWIFT CURRENT AT THE 12Z 6HR TIME STEP. THE
FRONT IS BEING FORCED BY THE UPPER WAVE EASTWARD AND DOESN/T MAKE
MUCH PROGRESS SOUTH. BY 18Z OR MID DAY THE FRONT ENTERS INTO
PHILLIPS COUNTY WITH THE PRE-FRONTAL TROUGH OVER THE EASTERN ZONES
WHERE THE NAM FIRES SOME CONVECTION ALONG IT. BY 00Z THE FRONT
SHOULD BE RIGHT ALONG THE ND/MT BORDER WITH THE UPPER TROUGH
MOVING THROUGH THE CENTRAL ZONES. PLAYED HIGH POPS TODAY OVER THE
EASTERN THIRD OF THE ZONES ALONG THE PRE-FRONTAL TROUGH AND ENDED
CONVECTIVE ACTIVITY WITH THE UPPER TROUGH AS IT MOVES THROUGH. THE
AREA SOUTH OF I-94 IS OUTLOOKED IN SPC DAY 1 FOR SLIGHT RISK. FOR
NOW FOR THE LATE AFTERNOON AND EARLY EVENING HOURS I WILL MENTIONS GUSTY
WINDS AND SMALL HAIL. NOT TOO EXCITED ABOUT SEVERE CONVECTIVE
ACTIVITY FOR THE REGION WITH THIS SYSTEM. PLUS...GIVEN THE REDUCED
CONFIDENCE WITH THE POOR MODEL HANDLING OF THE SITUATION..I WILL
NOT GET TOO OVER-EXCITED AT THIS TIME.
FOR TONIGHT AND SATURDAY... UPPER TROUGH SWINGS EAST DRYING UP THE
WEATHER FOR NORTHEAST MONTANA. WINDS SHOULD REMAIN BELOW LAKE
WIND LEVELS MAKING FOR A NICE LAKE SATURDAY IN QUIET AWHILE FOR
FORT PECK LAKE.
SUNDAY BRINGS ANOTHER UPPER TROUGH AND SURFACE FRONT FOR ANOTHER
ROUND OF CONVECTION FOR THE REGION. PROTON
.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY...
THE LONG TERM FORECAST PERIOD BEGINS AS A VERY TIGHTLY PACKED
UPPER LEVEL PRESSURE GRADIENT PULLS A NEARLY ZONAL FLOW THROUGH
THE NORTHERN ROCKIES WITH MULTIPLE VERY SUBTLE EMBEDDED SHORT WAVE
DISTURBANCES SETTING OFF REPEATED ROUNDS OF SHOWERS AND THUNDERSTORMS.
BY MONDAY MORNING...THAT ZONAL FLOW GIVES WAY TO A VERY LARGE
SCALE BROAD UPPER LEVEL TROUGH WHICH SPREADS FROM THE PACIFIC
NORTHWEST TO MINNESOTA WITH THE BASE OF THE TROUGH REACHING AS FAR
SOUTH AS NORTHERN UTAH. THIS WILL BE THE MAIN WEATHER PATTERN TO
AFFECT OUR CWA THROUGHOUT MOST OF THE WEEK. THE TWO MAIN STORM
SYSTEMS WHICH WILL PASS THROUGH WITH THIS BROAD TROUGH WILL BE
SOMETIME TUESDAY THROUGH THURSDAY AS SHOWN BY THE LARGE SCALE
FORCING FOR ASCENT BY THE GFS...BUT MAY ONLY AFFECT PORTIONS OF
OUR CWA.
THURSDAY NIGHT AND BEYOND...WEAK UPPER LEVEL RIDGING RETURNS TO
THE NORTHERN ROCKIES BRINGING A DRIER WEATHER TREND TO NORTHEAST
MONTANA WITH SOME SLIGHT DISAGREEMENT BETWEEN EXTENDED MODEL
SOLUTIONS AS ANOTHER UPPER LEVEL LOW CENTER LINGERS OF THE BRITISH
COLUMBIAN COASTLINE. BMICKELSON
&&
.AVIATION...
THANKS TO A BRIEF PERIOD OF WEAK UPPER LEVEL RIDGING...VFR
CONDITIONS WILL PREVAIL FOR ALL TAF SITES THROUGH THE MORNING
HOURS. LIGHT AND VARIABLE WINDS WILL BECOME BREEZY FROM THE WEST
AND NORTHWEST WITH GUSTS UP TO 25 MPH AS AN UPPER LEVEL
DISTURBANCE AND SURFACE FRONT PROVIDE THE FOCUS FOR SOME
CONVECTIVE SHOWERS AND THUNDERSTORMS DURING THE MID DAY AND
AFTERNOON HOURS. IT IS TO SOON TO TELL IF ANY SPECIFIC TAF SITE
WILL BE DIRECTLY AFFECTED...BUT VICINITY THUNDERSTORMS ARE
POSSIBLE AND AMENDMENTS DURING THE AFTERNOON WILL BE LIKELY.
BMICKELSON
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS HASTINGS NE
917 PM CDT SAT JUN 16 2012
.UPDATE...JUST COMPLETED UPDATE ADDRESSING THE REST OF TONIGHT.
ONLY CHANGE OF NOTE WAS TO PULL THUNDERSTORM CHANCES FROM THE
MAJORITY OF THE CWA THAT STILL HAD THEM THIS EVENING...BUT ALSO
ADDED A TOKEN 20 POP THROUGH THE OVERNIGHT HOURS TO THE BOTTOM ROW
OF 3 COUNTIES IN NORTH CENTRAL KANSAS. STRONGLY CONSIDERED LEAVING
ALL AREAS STORM-FREE...BUT WITH THE 23Z HRRR STUBBORNLY INSISTING
THAT SOME CONVECTION COULD BRUSH NORTHERN KS OVERNIGHT...OPTED TO
PLAY IT SAFE IN THE FAR SOUTH. OTHERWISE...00Z NAM JUST COMING
KEEPS THE ENTIRE CWA DRY OVERNIGHT...WITH ANY KS CONVECTION
REMAINING WELL SOUTH OF I-70. UNLIKE LAST NIGHT...THE ONGOING
EVENING STORM CLUSTERS/MCS ACTIVITY ARE FOCUSED ACROSS SOUTHEAST
CO INSTEAD OF NORTHEAST CO/NORTHWEST KS...AND THUS THE ODDS OF
ANYTHING TRACKING DUE EAST INTO THE CWA ARE QUITE SMALL. AS FOR
THE ODDS OF ISOLATED ACTIVITY DEVELOPING OVERHEAD...THIS SEEMS
LIKE A LONG SHOT AS WELL...WITH NAM FORECAST SOUNDINGS SHOWING A
PRETTY STOUT CAP EVEN TO ELEVATED PARCELS IN THE 850-700MB LAYER.
ALL THAT BEING SAID...WITH AT LEAST A WEAK LOW LEVEL JET GRADUALLY
VEERING INTO THE CWA AS THE NIGHT WEARS ON...AND HINTS OF SOME
THETA-E ADVECTION AT 700MB..JUST CAN/T COMPLETELY DISCOUNT THE
POSSIBILITY THAT A FEW SHOWERS/WEAK STORMS COULD FLARE UP INTO KS
ZONES TO THE NORTH OF THE MORE LIKELY ACTIVITY ACROSS SOUTHERN
PORTIONS OF THE STATE. TURNING TO OTHER ELEMENTS...MADE NO CHANGE
WHATSOEVER TO OVERNIGHT LOW TEMPS...WITH UPPER 50S NORTH TO MID
60S SOUTH STILL ON TRACK. FINALLY...PONDERED THE POSSIBILITY OF
ADDING PATCHY FOG MENTION OVERNIGHT...BUT UNLESS DEWPOINTS STAY UP
HIGHER THAN CURRENTLY THOUGHT...SUSPECT ANY VISIBILITY
RESTRICTIONS SHOULD ONLY AMOUNT TO A LIGHT HAZE ON THE ORDER OF
4-6 MILES...AND PROBABLY NOT WORTHY OF A FORMAL MENTION.
&&
.PREV DISCUSSION... /ISSUED 649 PM CDT SAT JUN 16 2012/
AVIATION...00Z KGRI TAF. COMPARED TO THE LAST FEW DAYS...THIS
SHOULD BE A MUCH QUIETER AND THUS HIGHER CONFIDENCE 24 HOURS OF
AVIATION FORECASTING...WITH VFR CEILING/VISIBILITY THROUGHOUT.
STARTING OFF TONIGHT...BREEZES WILL BE LIGHT/VARIABLE AS SURFACE
HIGH PRESSURE SLIDES BY TO THE NORTH AND EAST. ANY SMALL RISK OF
THUNDERSTORMS TONIGHT SHOULD REMAIN AT LEAST 80 MILES SOUTH OF
KGRI. BY SUNRISE...A BIT STEADIER SOUTHERLY WIND WILL BECOME
ESTABLISHED...WITH SPEEDS PICKING UP BY MID-LATE MORNING...AND
GUST POTENTIAL TO AROUND 23KT THROUGH THE AFTERNOON HOURS. ANY
LATE AFTERNOON THUNDERSTORM POTENTIAL SHOULD REMAIN AT LEAST 100
MILES NORTH-NORTHEAST OF KGRI.
PREV DISCUSSION... /ISSUED 340 PM CDT SAT JUN 16 2012/
SHORT TERM...THIS EVENING THROUGH SUNDAY. THERE WILL BE A SLIGHT
CHANCE OF A FEW SHOWERS AND THUNDERSTORMS AROUND LATE THIS AFTERNOON
INTO EARLY THIS EVENING...PRIMARILY SOUTHEAST OF A
FULLERTON...KEARNEY...ELWOOD LINE. ANY THUNDERSTORMS WILL BE RATHER
ISOLATED WITH MOST AREAS REMAINING DRY. SUNDAY WILL BE HOT AND DRY.
THIS EVENING INTO TONIGHT...THE COLD FRONT THAT TRACKED SOUTH
THROUGH OUR FORECAST AREA TODAY WILL WASHOUT ACROSS SOUTHERN KANSAS
TONIGHT. IT COULD STILL PROVE TO BE ENOUGH OF A FOCUSING MECHANISM
TO KICK OFF A FEW SHOWERS AND THUNDERSTORMS OVER PRIMARILY SOUTHERN
KANSAS THIS EVENING...WITH JUST THE SLIGHTEST CHANCE OF AN ISOLATED
THUNDERSTORM AS FAR NORTH AS OUR SOUTHERN CWA. ANY STORMS IN OUR
AREA WOULD PRIMARILY BE DUE TO AFTERNOON HEATING AND SHOULD DIE OUT
BY EARLY EVENING WITH THE LOSS OF THAT HEATING. MOST AREAS WILL
REMAIN DRY.
SUNDAY...THE FRONT WILL QUICKLY PUSH BACK NORTH AS A WARM FRONT ON
SUNDAY WITH SOUTH WINDS AND A VERY WARM ELEVATED MIXED LAYER
OVERSPREADING THE REGION. HIGH TEMPERATURES WILL EASILY CLIMB BACK
INTO THE 90S WITH MID TO UPPER 90S POSSIBLE ACROSS NORTHERN KANSAS.
THE WARM ELEVATED MIXED LAYER SHOULD KEEP THE ENVIRONMENT VERY
CAPPED. AN ISOLATED THUNDERSTORM COULD POSSIBLY OVERCOME THE CAP
NORTH OF HIGHWAY 92...BUT THIS POSSIBILITY IS LOW AND THE COVERAGE
AREA OF ANY CONVECTION WOULD BE VERY LIMITED. CONSEQUENTLY WE WILL
CONTINUE TO GO WITH A DRY FORECAST WITH RAIN CHANCES ONLY AT 10
PERCENT OR LESS.
LONG TERM...00Z MONDAY THROUGH FRIDAY. CONCERNS IN THIS TIME FRAME
INCLUDE HOT TEMPERATURES EARLY IN THE WORK WEEK AND THEN CHANCE OF
RAIN TUESDAY NIGHT INTO THURSDAY NIGHT OR FRIDAY.
EXTENDED MODELS IN PRETTY GOOD AGREEMENT WITH THE BASIC PATTERN OF
STARTING OUT IN ZONAL FLOW WITH THE BEST JET ACTION ACROSS THE
NORTHERN PLAINS AT 00Z MONDAY...AND THEN TRANSITIONING TO MORE OF A
BROAD TROUGH ACROSS THE NORTHERN ROCKIES/NORTHERN PLAINS WITH
RIDGING ACROSS THE EASTERN U.S. BY TUESDAY NIGHT...AND THEN THE
TROUGH WILL WORK EAST AND EVENTUALLY WE SEE PRETTY GOOD RIDGING
BUILDING INTO THE HIGH PLAINS BY NEXT FRIDAY/INTO THE WEEKEND.
STARTING OUT SUNDAY EVENING...LOOKS LIKE A WARM FRONT SHOULD HAVE
WORKED WELL NORTH OF THE CWA WITH A DRY LINE TO THE WEST. BETTER MID
LEVEL FORCING SHOULD ALSO BE NORTH OF THE AREA AND WARMER MID LEVEL
TEMPS WILL BE BUILDING IN FROM THE SOUTHWEST. WILL LEAVE FORECAST
DRY AS BETTER CHANCES APPEAR TO BE NORTH FOR REASONS MENTIONED
ABOVE.
MONDAY WILL BE DOWNRIGHT HOT WITH 850 PROGGED TEMPS ANYWHERE FROM
THE UPPER 20S TO LOWER 30S CELSIUS IN THE WESTERN PART OF THE CWA
DEPENDING ON WHICH MODEL ONE GOES WITH. NAM LOOKS TO BE THE WARMEST
OF THE MODELS AS IT BRINGS DRY LINE A LITTLE FURTHER EAST INTO OUR
CWA WHILE GFS JUST A BIT WEST OF THAT POSITION. THIS WOULD ALLOW THE
NAM TO PRODUCE SURFACE WINDS WITH MORE OF A SOUTHWEST COMPONENT
WHICH WOULD FAVOR PARTS OF THE CWA REACHING OR EXCEEDING THE CENTURY
MARK. WILL COMPARE THE LATEST EC MODEL RUN WHEN IT COMES IN. SHOULD
REMAIN DRY MONDAY NIGHT INTO TUESDAY WITH VERY WARM MID LEVEL TEMPS
OF 14 TO 17C AT 700 MB KEEPING THINGS CAPPED.
CHANCES OF RAIN THEN BEGIN TO INCREASE BY TUESDAY NIGHT AS SURFACE
FRONT PUSHES INTO THE NORTHWEST PART OF THE CWA. OUTSIDE CHANCE OF A
LATE AFTERNOON TSTM IN THE NW BUT WILL LEAVE MENTION OUT FOR NOW AS
WE SHOULD STILL BE CAPPED. WILL MOST LIKELY CONTINUE PREVIOUS
THINKING AND CONFINE RAIN CHANCES TO AREAS ALONG AND NORTH OF
HASTINGS FOR TUESDAY NIGHT.
APPEARS THAT FRONT SHOULD HANG UP SOMEWHERE ACROSS SOUTHERN NEB OR
ACROSS KANSAS FOR WEDNESDAY AND THURSDAY. EXACT LOCATION EACH DAY
WILL DICTATE PRECIPITATION REGION. WOULD THINK BETTER CHANCES SHOULD
BE AT NIGHT AS LOW LEVEL JET TRANSPORTS WARM AND MOIST AIR OVER THE
BOUNDARY. AS FAR AS SEVERE WEATHER IS CONCERNED...THERE ARE A FEW
PERIODS WHERE INSTABILITY IS RESPECTABLE AS SEEN ON EC CAPE
PROJECTIONS...BUT DEEP LAYER SHEAR VALUES LACKING DURING THE TUESDAY
THROUGH THURSDAY NIGHT TIME FRAME.
AS NOTED ABOVE...RIDGING IS PROGGED TO BUILD BACK IN STARTING
FRIDAY. OVERALL THIS SHOULD KEEP THINGS DRY INTO THE START OF THE
NEXT WORK WEEK AND THE HEAT WILL ALSO RETURN. IF THE RIDGE DOES
BUILD IN AS EXPECTED...IT SHOULD PUT US IN THE RING-OF-FIRE
SCENARIO...LEADING TO DRY WEATHER UNLESS SOMETHING CAN WORK DOWN
OVER THE TOP OF THE RIDGE FROM THE NW.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE/AVIATION...PFANNKUCH
SHORT TERM...WESELY
LONG TERM...EWALD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1055 PM EDT SAT JUN 16 2012
.SYNOPSIS...
UNSEASONABLY COOL TEMPERATURES THIS WEEKEND WILL TRANSITION TO
MORE TYPICAL JUNE WARMTH THROUGH EARLY NEXT WEEK AS AN UPPER RIDGE
DEVELOPS OVER THE REGION. THE RIDGE WILL MAINTAIN GENERALLY DRY
CONDITIONS FOR MUCH OF THE FORECAST PERIOD. A COLD FRONT MAY
APPROACH THE AREA LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AS OF 11:00 PM SATURDAY...ABSOLUTELY NO CHANGES TO THE WEATHER
PICTURE OVER THE PAST FEW HOURS. SATELLITE LOOPS AND MODEL
GUIDANCE CONTINUE TO SHOW THAT PATCHY CIRRUS WILL STREAM SOUTH
ACROSS THE AREA OVERNIGHT. ANOTHER COOL AND DRY OVERNIGHT PERIOD.
PREVIOUS DISCUSSION FROM THIS AFTERNOON FOLLOWS:
THIS NORTHEAST FLOW WILL MAINTAIN RELATIVELY COOLER AND DRIER
WEATHER FOR THE MOST PART. LIMITED MOISTURE WILL CONTINUE TO
STREAM AROUND THE HIGH IN THE NORTHEAST FLOW. HRRR SHOWS A NICE
DEPICTION OF THIS MOISTURE IN TERMS OF CU DEVELOPMENT. VALUES OF
LESS THAN A HALF INCH INLAND WHERE CLEAR SKIES EXIST UP TO .75
INCHES IN PATCHES WHERE CU DEVELOPED CLOSER TO THE COAST. SEA
BREEZE PUSHED JUST FAR ENOUGH INLAND TO KEEP TIP OF CAPE FEAR
CLEAR OF ANY CLOUDS. SOUNDING DATA AND MOISTURE PROFILES SHOW
LAYER OF MOISTURE LOCKED IN BELOW INVERSION JUST UNDER 7K FT
DRYING OUT THROUGH THIS EVENING. HRRR SHOWS PCP WATER DOWN LESS
THAN A HALF INCH OVER AREA TONIGHT. ONCE THE CU DISSIPATE BY
EVENING...EXPECT CLEAR SKIES THROUGH MORNING.
COOL NORTHEAST FLOW AND SOME CAA WILL KEEP TEMPS BELOW NORMAL ONCE
AGAIN. AS THE GRADIENT WEAKENS TONIGHT AND THE ATMOSPHERE
DECOUPLES AFTER SUNSET...CALM AND CLEAR CONDITIONS WILL PRODUCE MORE
IDEAL RADIATIONAL COOLING. THEREFORE ANOTHER COOL NIGHT IS IN
STORE WITH TEMPS DOWN BELOW 60.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
AS OF 255 PM SATURDAY...A WARMING TREND WILL OCCUR IN THIS PERIOD
AS AN UPPER RIDGE BEGINS TO EXPAND OVER THE AREA COUPLED WITH
SURFACE HIGH PRESSURE MOVING OFFSHORE LATE SUNDAY. WITH LIGHT
WIND AND GENERALLY CLEAR SKIES...WE WILL SEE MINIMUM TEMPS BELOW
NORMAL FOR MIDDLE JUNE BOTH MON/TUE AT DAYBREAK...MAINLY LOW AND
MIDDLE 60S.
INTRODUCED A SLIGHT CHANCE OF A SHOWER OVER OUR FAR INTERIOR
MONDAY AFTERNOON AS WEAK SHORTWAVE ENERGY DROPS OVER TOP OF THE
UPPER RIDGE. MOISTURE ENHANCEMENT IS EVIDENT IN RH TIME-HEIGHT
PLOTS IN THE BOUNDARY LAYER UP TO 500 MB. CONCURRENTLY WE SHOULD
HAVE SOME FORM OF SEA BREEZE CONVERGENCE WELL INLAND TO GIVE US
A CRACK AT A BRIEF SHOWER OVER OUR NW ZONES 3PM-6PM MONDAY.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 255 PM SATURDAY...SURFACE HIGH PRESSURE COMBINED WITH UPPER
RIDGING CREATES SUMMER-LIKE WEATHER DURING THE WEEK WITH DRY AND
WARM CONDITIONS EXPECTED THROUGH FRIDAY. UPPER RIDGE AXIS SHIFTS
EAST ON TUESDAY...AND ALTHOUGH A WEAK SHORTWAVE WILL DROP SOUTH OVER
THE CAROLINAS DURING THE DAY...A DRY COLUMN AND SUBSIDENCE BENEATH
THE RIDGE WILL INHIBIT ANYTHING OTHER THAN SOME ENHANCED MID LEVEL
CLOUD COVER. 500MB RIDGE SHIFTS DIRECTLY OVERHEAD WED-FRI ALLOWING
TEMPS TO WARM TO ABOVE CLIMO THROUGH THE END OF THE WEEK WITH AMPLE
SUNSHINE. RIDGE THEN BEGINS TO BREAK DOWN AHEAD OF A SHORTWAVE WHICH
WILL TRY TO DRIVE A COLD FRONT THROUGH THE AREA LATE SATURDAY. THIS
IS FASTER THAN PREVIOUS MODELS...BUT RECOGNIZE THAT STRONG RIDGES
TEND TO DELAY COLD FRONTS SO CURRENT PROGS MAY BE TOO FAST TO BRING
THROUGH FRONT SATURDAY. COMBINE THIS WITH LACK OF SIGNIFICANT
FORCING AND WILL BUMP POP TO SCHC...BUT NOT HIGH ENOUGH TO MENTION
IN THE FORECAST 7 DAYS OUT.
TEMPS TUESDAY WILL BE RIGHT AROUND CLIMO BEFORE RISING THROUGH THE
REST OF THE WEEK. 850MB TEMPS RISE TO 18-20C BY FRIDAY...BUT
EASTERLY MID LEVEL FLOW WILL INHIBIT US FROM REALIZING THE FULL
POTENTIAL OF THIS WARMTH ALOFT UNTIL FRIDAY WHEN WINDS SHIFT TO THE
SW THROUGH THE COLUMN...AND FRIDAY LOOKS TO BE THE WARMEST DAY OF
THE PERIOD. STILL...TEMPS WILL BE ABOVE CLIMO WED-SAT...LOW 90S MOST
PLACES AWAY FROM THE BEACHES. MINS AT NIGHT WILL FALL ONLY TO THE
UPPER 60S WED NIGHT...AND AROUND 70 THE REST OF THE WEEK.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
AS OF 00Z...VFR WILL PREVAIL THROUGH THE VALID TAF PERIOD. EXPECT
LIGHT NORTHEAST WINDS THROUGH THE OVERNIGHT HOURS WITH NEARLY CLEAR
SKIES. AFTER DAYBREAK...NORTHEAST WINDS WILL INCREASE TO AOB 11 KTS
AT ALL TERMINALS...WITH A DEVELOPING SEABREEZE IN THE AFTERNOON
VEERING WINDS TO BECOME EAST-SOUTHEAST AT THE COASTAL SITES.
ANTICIPATE DIURNAL CU TO DEVELOP AGAIN THROUGHOUT THE AFTN PERIOD
AROUND 4KFT. TOWARDS EVENING...WINDS WILL BECOME LIGHT WITH
LINGERING CLOUDS GRADUALLY DISSIPATING.
EXTENDED OUTLOOK...VFR THROUGH THE FORECAST PERIOD. A SLIGHT
CHANCE OF SHOWERS TUESDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 11:00 PM SATURDAY...LATEST COASTAL AND BUOY OBS SHOW AN
UNEXPECTEDLY STRONG COLD SURGE MOVING ACROSS OUR NC WATERS...WITH
WINDS UP IN THE 20 KT RANGE ALONG THE COAST. SEAS HAVE KICKED UP
TO 4 TO 5 FT AS A RESULT. EXPECT THIS TO BE TEMPORARY AS OVERALL
GRADIENT RELAXES. HAVE ADDED EXERCISE CAUTION HEADLINES TO OUR NC
WATERS FOR THE NEAR TERM. PREVIOUS DISCUSSION FOLLOWS:
A CUTOFF LOW CLOSE TO THE BAHAMAS WILL MEANDER AROUND BUT THE HIGH
PRESSURE REACHING INTO LOCAL WATERS FROM THE NORTH WILL WEAKEN
THROUGH TONIGHT. THIS WILL ALLOW THE GRADIENT TO RELAX FURTHER AND
EXPECT SEAS TO RESPOND BY SUBSIDING THROUGH SUN MORNING. LATEST
OBS SHOWING SEAS UNDER 6 FT IN LOCAL WATERS. THEREFORE ALL SMALL
CRAFT ADVISORIES WILL BE DISCONTINUED WITH AFTERNOON PACKAGE.
PERSISTENT NORTHEAST WINDS AROUND 15 KTS WILL DIMINISH THROUGH
TONIGHT DOWN TO 10 TO 15 KTS BY MORNING. THIS WILL ALLOW SEAS TO
COME DOWN FROM AROUND 5 FT IN OUTER WATERS TO 2 TO 4 FT BY MORNING
ACROSS MOST WATERS. THE SEAS WILL REMAIN A MIX OF NE SWELL WITH
NEARLY A 9 SEC PERIOD AND LOCALLY WIND DRIVEN SHORTER PERIOD
SWELL.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 255 PM SATURDAY...SUNDAY AFTERNOON AND EVENING WILL MARK A
TRANSITION IN WIND DIRECTION AS A SURFACE HIGH PRESENTLY OVER
LAND...SLIPS OFFSHORE AND BRINGS WINDS AROUND WITH A SOUTHERLY
COMPONENT. THIS WILL LIKELY OCCUR SUNDAY AFTERNOON AS THE SEA
BREEZE CIRCULATION HASTENS THE TRANSITION...S-SE WINDS 10-15 KT
SUNDAY AFTERNOON...EASING TO S-SW 5 KT OVERNIGHT SUNDAY. SOUTH
WINDS MONDAY AS THE HIGH HOLDS JUST OFFSHORE OF OUR COAST.
WAVE DIRECTION BOTH SUNDAY AND MONDAY WILL HOLD FROM AN EASTERLY
DIRECTION...WITH GRADUALLY DECREASING WAVE HEIGHTS SUNDAY INTO
MONDAY. SOME NEAR SHORE CHOPPINESS WILL OCCUR SUNDAY AND MONDAY
AFTERNOON...AS THE SEA BREEZE ENHANCES WIND SPEEDS SEVERAL KTS.
LONG TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 255 PM SATURDAY...HIGH PRESSURE EXTENDING ACROSS THE WATERS
THROUGH THE LONG TERM CREATES LIGHT WINDS AND INCREASING SE SWELL.
WINDS OF AROUND 10 KTS WILL PERSIST THROUGH THE PERIOD...AND WILL
HAVE A PREDOMINANT SOUTHERLY COMPONENT WITH ONLY MINOR TEMPORAL
FLUCTUATIONS TO SE OR SW. SINCE THESE WINDS WILL BE LIGHT...THE WAVE
SPECTRUM WILL BE ALMOST ENTIRELY SWELL DOMINATED. A 2FT/8SEC E/SE
SWELL WILL START THE PERIOD...BUILDING TO A 3FT/8SEC SE SWELL AS
RETURN FLOW CONTINUES AROUND HIGH PRESSURE. SEAS WILL BE ONLY 1-2
FT THROUGH WEDNESDAY...BUILDING TO 2-3 FT LATE THURSDAY DUE TO
THE INCREASED SWELL AMPLITUDE.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...REK/RGZ
SHORT TERM...MJC
LONG TERM...JDW
AVIATION...SGL
MARINE...MJC/REK/JDW/RGZ
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
753 PM EDT SAT JUN 16 2012
.SYNOPSIS...
UNSEASONABLY COOL TEMPERATURES THIS WEEKEND WILL TRANSITION TO
MORE TYPICAL JUNE WARMTH THROUGH EARLY NEXT WEEK AS AN UPPER RIDGE
DEVELOPS OVER THE REGION. THE RIDGE WILL MAINTAIN GENERALLY DRY
CONDITIONS FOR MUCH OF THE FORECAST PERIOD. A COLD FRONT MAY
APPROACH THE AREA LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AS OF 8:00 PM SATURDAY...WINDS HAVE BEEN ON THE DECLINE AS
PRESSURE GRADIENT RELAXES THIS EVENING. CU CLOUDS HAVE ALSO BEEN
ON THE DECLINE WITH LOSS OF DAYTIME HEATING. SATELLITE LOOPS SHOW
PATCHY CIRRUS WILL CONTINUE TO STREAM SOUTH ACROSS THE AREA
OVERNIGHT. NO CHANGES TO GOING FORECAST...ANOTHER COOL AND DRY
OVERNIGHT PERIOD. PREVIOUS DISCUSSION FOLLOWS:
THIS NORTHEAST FLOW WILL MAINTAIN RELATIVELY COOLER AND DRIER
WEATHER FOR THE MOST PART. LIMITED MOISTURE WILL CONTINUE TO
STREAM AROUND THE HIGH IN THE NORTHEAST FLOW. HRRR SHOWS A NICE
DEPICTION OF THIS MOISTURE IN TERMS OF CU DEVELOPMENT. VALUES OF
LESS THAN A HALF INCH INLAND WHERE CLEAR SKIES EXIST UP TO .75
INCHES IN PATCHES WHERE CU DEVELOPED CLOSER TO THE COAST. SEA
BREEZE PUSHED JUST FAR ENOUGH INLAND TO KEEP TIP OF CAPE FEAR
CLEAR OF ANY CLOUDS. SOUNDING DATA AND MOISTURE PROFILES SHOW
LAYER OF MOISTURE LOCKED IN BELOW INVERSION JUST UNDER 7K FT
DRYING OUT THROUGH THIS EVENING. HRRR SHOWS PCP WATER DOWN LESS
THAN A HALF INCH OVER AREA TONIGHT. ONCE THE CU DISSIPATE BY
EVENING...EXPECT CLEAR SKIES THROUGH MORNING.
COOL NORTHEAST FLOW AND SOME CAA WILL KEEP TEMPS BELOW NORMAL ONCE
AGAIN. AS THE GRADIENT WEAKENS TONIGHT AND THE ATMOSPHERE
DECOUPLES AFTER SUNSET...CALM AND CLEAR CONDITIONS WILL PRODUCE MORE
IDEAL RADIATIONAL COOLING. THEREFORE ANOTHER COOL NIGHT IS IN
STORE WITH TEMPS DOWN BELOW 60.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
AS OF 255 PM SATURDAY...A WARMING TREND WILL OCCUR IN THIS PERIOD
AS AN UPPER RIDGE BEGINS TO EXPAND OVER THE AREA COUPLED WITH
SURFACE HIGH PRESSURE MOVING OFFSHORE LATE SUNDAY. WITH LIGHT
WIND AND GENERALLY CLEAR SKIES...WE WILL SEE MINIMUM TEMPS BELOW
NORMAL FOR MIDDLE JUNE BOTH MON/TUE AT DAYBREAK...MAINLY LOW AND
MIDDLE 60S.
INTRODUCED A SLIGHT CHANCE OF A SHOWER OVER OUR FAR INTERIOR
MONDAY AFTERNOON AS WEAK SHORTWAVE ENERGY DROPS OVER TOP OF THE
UPPER RIDGE. MOISTURE ENHANCEMENT IS EVIDENT IN RH TIME-HEIGHT
PLOTS IN THE BOUNDARY LAYER UP TO 500 MB. CONCURRENTLY WE SHOULD
HAVE SOME FORM OF SEA BREEZE CONVERGENCE WELL INLAND TO GIVE US
A CRACK AT A BRIEF SHOWER OVER OUR NW ZONES 3PM-6PM MONDAY.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 255 PM SATURDAY...SURFACE HIGH PRESSURE COMBINED WITH UPPER
RIDGING CREATES SUMMER-LIKE WEATHER DURING THE WEEK WITH DRY AND
WARM CONDITIONS EXPECTED THROUGH FRIDAY. UPPER RIDGE AXIS SHIFTS
EAST ON TUESDAY...AND ALTHOUGH A WEAK SHORTWAVE WILL DROP SOUTH OVER
THE CAROLINAS DURING THE DAY...A DRY COLUMN AND SUBSIDENCE BENEATH
THE RIDGE WILL INHIBIT ANYTHING OTHER THAN SOME ENHANCED MID LEVEL
CLOUD COVER. 500MB RIDGE SHIFTS DIRECTLY OVERHEAD WED-FRI ALLOWING
TEMPS TO WARM TO ABOVE CLIMO THROUGH THE END OF THE WEEK WITH AMPLE
SUNSHINE. RIDGE THEN BEGINS TO BREAK DOWN AHEAD OF A SHORTWAVE WHICH
WILL TRY TO DRIVE A COLD FRONT THROUGH THE AREA LATE SATURDAY. THIS
IS FASTER THAN PREVIOUS MODELS...BUT RECOGNIZE THAT STRONG RIDGES
TEND TO DELAY COLD FRONTS SO CURRENT PROGS MAY BE TOO FAST TO BRING
THROUGH FRONT SATURDAY. COMBINE THIS WITH LACK OF SIGNIFICANT
FORCING AND WILL BUMP POP TO SCHC...BUT NOT HIGH ENOUGH TO MENTION
IN THE FORECAST 7 DAYS OUT.
TEMPS TUESDAY WILL BE RIGHT AROUND CLIMO BEFORE RISING THROUGH THE
REST OF THE WEEK. 850MB TEMPS RISE TO 18-20C BY FRIDAY...BUT
EASTERLY MID LEVEL FLOW WILL INHIBIT US FROM REALIZING THE FULL
POTENTIAL OF THIS WARMTH ALOFT UNTIL FRIDAY WHEN WINDS SHIFT TO THE
SW THROUGH THE COLUMN...AND FRIDAY LOOKS TO BE THE WARMEST DAY OF
THE PERIOD. STILL...TEMPS WILL BE ABOVE CLIMO WED-SAT...LOW 90S MOST
PLACES AWAY FROM THE BEACHES. MINS AT NIGHT WILL FALL ONLY TO THE
UPPER 60S WED NIGHT...AND AROUND 70 THE REST OF THE WEEK.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
AS OF 00Z...VFR WILL PREVAIL THROUGH THE VALID TAF PERIOD. EXPECT
LIGHT NORTHEAST WINDS THROUGH THE OVERNIGHT HOURS WITH NEARLY CLEAR
SKIES. AFTER DAYBREAK...NORTHEAST WINDS WILL INCREASE TO AOB 11 KTS
AT ALL TERMINALS...WITH A DEVELOPING SEABREEZE IN THE AFTERNOON
VEERING WINDS TO BECOME EAST-SOUTHEAST AT THE COASTAL SITES.
ANTICIPATE DIURNAL CU TO DEVELOP AGAIN THROUGHOUT THE AFTN PERIOD
AROUND 4KFT. TOWARDS EVENING...WINDS WILL BECOME LIGHT WITH
LINGERING CLOUDS GRADUALLY DISSIPATING.
EXTENDED OUTLOOK...VFR THROUGH THE FORECAST PERIOD. A SLIGHT
CHANCE OF SHOWERS TUESDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 8:00 PM SATURDAY...LATEST COASTAL AND BUOY OBS SHOW SEAS OF
3 TO 5 FT WITH EASTERLY WINDS IN THE 10 TO 15 KT RANGE THIS
EVENING. EXPECT LITTLE CHANGE FROM THESE CONDITIONS FOR THE
REMAINDER OF THE NEAR TERM. PREVIOUS DISCUSSION FOLLOWS:
A CUTOFF LOW CLOSE TO THE BAHAMAS WILL MEANDER AROUND BUT THE HIGH
PRESSURE REACHING INTO LOCAL WATERS FROM THE NORTH WILL WEAKEN
THROUGH TONIGHT. THIS WILL ALLOW THE GRADIENT TO RELAX FURTHER AND
EXPECT SEAS TO RESPOND BY SUBSIDING THROUGH SUN MORNING. LATEST
OBS SHOWING SEAS UNDER 6 FT IN LOCAL WATERS. THEREFORE ALL SMALL
CRAFT ADVISORIES WILL BE DISCONTINUED WITH AFTERNOON PACKAGE.
PERSISTENT NORTHEAST WINDS AROUND 15 KTS WILL DIMINISH THROUGH
TONIGHT DOWN TO 10 TO 15 KTS BY MORNING. THIS WILL ALLOW SEAS TO
COME DOWN FROM AROUND 5 FT IN OUTER WATERS TO 2 TO 4 FT BY MORNING
ACROSS MOST WATERS. THE SEAS WILL REMAIN A MIX OF NE SWELL WITH
NEARLY A 9 SEC PERIOD AND LOCALLY WIND DRIVEN SHORTER PERIOD
SWELL.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 255 PM SATURDAY...SUNDAY AFTERNOON AND EVENING WILL MARK A
TRANSITION IN WIND DIRECTION AS A SURFACE HIGH PRESENTLY OVER
LAND...SLIPS OFFSHORE AND BRINGS WINDS AROUND WITH A SOUTHERLY
COMPONENT. THIS WILL LIKELY OCCUR SUNDAY AFTERNOON AS THE SEA
BREEZE CIRCULATION HASTENS THE TRANSITION...S-SE WINDS 10-15 KT
SUNDAY AFTERNOON...EASING TO S-SW 5 KT OVERNIGHT SUNDAY. SOUTH
WINDS MONDAY AS THE HIGH HOLDS JUST OFFSHORE OF OUR COAST.
WAVE DIRECTION BOTH SUNDAY AND MONDAY WILL HOLD FROM AN EASTERLY
DIRECTION...WITH GRADUALLY DECREASING WAVE HEIGHTS SUNDAY INTO
MONDAY. SOME NEAR SHORE CHOPPINESS WILL OCCUR SUNDAY AND MONDAY
AFTERNOON...AS THE SEA BREEZE ENHANCES WIND SPEEDS SEVERAL KTS.
LONG TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 255 PM SATURDAY...HIGH PRESSURE EXTENDING ACROSS THE WATERS
THROUGH THE LONG TERM CREATES LIGHT WINDS AND INCREASING SE SWELL.
WINDS OF AROUND 10 KTS WILL PERSIST THROUGH THE PERIOD...AND WILL
HAVE A PREDOMINANT SOUTHERLY COMPONENT WITH ONLY MINOR TEMPORAL
FLUCTUATIONS TO SE OR SW. SINCE THESE WINDS WILL BE LIGHT...THE WAVE
SPECTRUM WILL BE ALMOST ENTIRELY SWELL DOMINATED. A 2FT/8SEC E/SE
SWELL WILL START THE PERIOD...BUILDING TO A 3FT/8SEC SE SWELL AS
RETURN FLOW CONTINUES AROUND HIGH PRESSURE. SEAS WILL BE ONLY 1-2
FT THROUGH WEDNESDAY...BUILDING TO 2-3 FT LATE THURSDAY DUE TO
THE INCREASED SWELL AMPLITUDE.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...REK/RGZ
SHORT TERM...MJC
LONG TERM...JDW
AVIATION...SGL
MARINE...MJC/REK/JDW/RGZ
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
735 PM EDT SAT JUN 16 2012
.SYNOPSIS...
UNSEASONABLY COOL TEMPERATURES THIS WEEKEND WILL TRANSITION TO
MORE TYPICAL JUNE WARMTH THROUGH EARLY NEXT WEEK...AS AN UPPER
RIDGE DEVELOPS OVER THE REGION. THE RIDGE WILL MAINTAIN GENERALLY
DRY CONDITIONS AND RAIN CHANCES REMAIN SLIM MUCH OF THE FORECAST
PERIOD. A COLD FRONT MAY APPROACH THE AREA LATE IN THE WEEK.
&&
.NEAR TERM /THROUGH SUNDAY/...
AS OF 255 PM SATURDAY...HIGH PRESSURE WILL WEAKEN A BIT AS IT
CONTINUES TO RIDGE DOWN INTO THE CAROLINAS FROM JUST OFF NEW
ENGLAND COAST THROUGH TONIGHT. THIS WILL ALLOW THE GRADIENT TO
RELAX AND WINDS TO COME DOWN. THEREFORE GUSTY NORTHEAST WINDS WILL
LET UP SOMEWHAT THROUGH TONIGHT.
THIS NORTHEAST FLOW WILL MAINTAIN RELATIVELY COOLER AND DRIER
WEATHER FOR THE MOST PART. LIMITED MOISTURE WILL CONTINUE TO
STREAM AROUND THE HIGH IN THE NORTHEAST FLOW. HRRR SHOWS A NICE
DEPICTION OF THIS MOISTURE IN TERMS OF CU DEVELOPMENT. VALUES OF
LESS THAN A HALF INCH INLAND WHERE CLEAR SKIES EXIST UP TO .75
INCHES IN PATCHES WHERE CU DEVELOPED CLOSER TO THE COAST. SEA
BREEZE PUSHED JUST FAR ENOUGH INLAND TO KEEP TIP OF CAPE FEAR
CLEAR OF ANY CLOUDS. SOUNDING DATA AND MOISTURE PROFILES SHOW
LAYER OF MOISTURE LOCKED IN BELOW INVERSION JUST UNDER 7K FT
DRYING OUT THROUGH THIS EVENING. HRRR SHOWS PCP WATER DOWN LESS
THAN A HALF INCH OVER AREA TONIGHT. ONCE THE CU DISSIPATE BY
EVENING...EXPECT CLEAR SKIES THROUGH MORNING.
COOL NORTHEAST FLOW AND SOME CAA WILL KEEP TEMPS BELOW NORMAL ONCE
AGAIN. AS THE GRADIENT WEAKENS TONIGHT AND THE ATMOSPHERE
DECOUPLES AFTER SUNSET...CALM AND CLEAR CONDITIONS WILL PRODUCE MORE
IDEAL RADIATIONAL COOLING. THEREFORE ANOTHER COOL NIGHT IS IN
STORE WITH TEMPS DOWN BELOW 60.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
AS OF 255 PM SATURDAY...A WARMING TREND WILL OCCUR IN THIS PERIOD
AS AN UPPER RIDGE BEGINS TO EXPAND OVER THE AREA COUPLED WITH
SURFACE HIGH PRESSURE MOVING OFFSHORE LATE SUNDAY. WITH LIGHT
WIND AND GENERALLY CLEAR SKIES...WE WILL SEE MINIMUM TEMPS BELOW
NORMAL FOR MIDDLE JUNE BOTH MON/TUE AT DAYBREAK...MAINLY LOW AND
MIDDLE 60S.
INTRODUCED A SLIGHT CHANCE OF A SHOWER OVER OUR FAR INTERIOR
MONDAY AFTERNOON AS WEAK SHORTWAVE ENERGY DROPS OVER TOP OF THE
UPPER RIDGE. MOISTURE ENHANCEMENT IS EVIDENT IN RH TIME-HEIGHT
PLOTS IN THE BOUNDARY LAYER UP TO 500 MB. CONCURRENTLY WE SHOULD
HAVE SOME FORM OF SEA BREEZE CONVERGENCE WELL INLAND TO GIVE US
A CRACK AT A BRIEF SHOWER OVER OUR NW ZONES 3PM-6PM MONDAY.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 255 PM SATURDAY...SURFACE HIGH PRESSURE COMBINED WITH UPPER
RIDGING CREATES SUMMER-LIKE WEATHER DURING THE WEEK WITH DRY AND
WARM CONDITIONS EXPECTED THROUGH FRIDAY. UPPER RIDGE AXIS SHIFTS
EAST ON TUESDAY...AND ALTHOUGH A WEAK SHORTWAVE WILL DROP SOUTH OVER
THE CAROLINAS DURING THE DAY...A DRY COLUMN AND SUBSIDENCE BENEATH
THE RIDGE WILL INHIBIT ANYTHING OTHER THAN SOME ENHANCED MID LEVEL
CLOUD COVER. 500MB RIDGE SHIFTS DIRECTLY OVERHEAD WED-FRI ALLOWING
TEMPS TO WARM TO ABOVE CLIMO THROUGH THE END OF THE WEEK WITH AMPLE
SUNSHINE. RIDGE THEN BEGINS TO BREAK DOWN AHEAD OF A SHORTWAVE WHICH
WILL TRY TO DRIVE A COLD FRONT THROUGH THE AREA LATE SATURDAY. THIS
IS FASTER THAN PREVIOUS MODELS...BUT RECOGNIZE THAT STRONG RIDGES
TEND TO DELAY COLD FRONTS SO CURRENT PROGS MAY BE TOO FAST TO BRING
THROUGH FRONT SATURDAY. COMBINE THIS WITH LACK OF SIGNIFICANT
FORCING AND WILL BUMP POP TO SCHC...BUT NOT HIGH ENOUGH TO MENTION
IN THE FORECAST 7 DAYS OUT.
TEMPS TUESDAY WILL BE RIGHT AROUND CLIMO BEFORE RISING THROUGH THE
REST OF THE WEEK. 850MB TEMPS RISE TO 18-20C BY FRIDAY...BUT
EASTERLY MID LEVEL FLOW WILL INHIBIT US FROM REALIZING THE FULL
POTENTIAL OF THIS WARMTH ALOFT UNTIL FRIDAY WHEN WINDS SHIFT TO THE
SW THROUGH THE COLUMN...AND FRIDAY LOOKS TO BE THE WARMEST DAY OF
THE PERIOD. STILL...TEMPS WILL BE ABOVE CLIMO WED-SAT...LOW 90S MOST
PLACES AWAY FROM THE BEACHES. MINS AT NIGHT WILL FALL ONLY TO THE
UPPER 60S WED NIGHT...AND AROUND 70 THE REST OF THE WEEK.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
AS OF 00Z...VFR WILL PREVAIL THROUGH THE VALID TAF PERIOD. EXPECT
LIGHT NORTHEAST WINDS THROUGH THE OVERNIGHT HOURS WITH NEARLY CLEAR
SKIES. AFTER DAYBREAK...NORTHEAST WINDS WILL INCREASE TO AOB 11 KTS
AT ALL TERMINALS...WITH A DEVELOPING SEABREEZE IN THE AFTERNOON
VEERING WINDS TO BECOME EAST-SOUTHEAST AT THE COASTAL SITES.
ANTICIPATE DIURNAL CU TO DEVELOP AGAIN THROUGHOUT THE AFTN PERIOD
AROUND 4KFT. TOWARDS EVENING...WINDS WILL BECOME LIGHT WITH
LINGERING CLOUDS GRADUALLY DISSIPATING.
EXTENDED OUTLOOK...VFR THROUGH THE FORECAST PERIOD. A SLIGHT
CHANCE OF SHOWERS TUESDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 255 PM SATURDAY... A CUTOFF LOW CLOSE TO THE BAHAMAS WILL
MEANDER AROUND BUT THE HIGH PRESSURE REACHING INTO LOCAL WATERS
FROM THE NORTH WILL WEAKEN THROUGH TONIGHT. THIS WILL ALLOW THE
GRADIENT TO RELAX FURTHER AND EXPECT SEAS TO RESPOND BY
SUBSIDING THROUGH SUN MORNING. LATEST OBS SHOWING SEAS UNDER 6 FT
IN LOCAL WATERS. THEREFORE ALL SMALL CRAFT ADVISORIES WILL BE
DISCONTINUED WITH AFTERNOON PACKAGE. PERSISTENT NORTHEAST WINDS
AROUND 15 KTS WILL DIMINISH THROUGH TONIGHT DOWN TO 10 TO 15 KTS
BY MORNING. THIS WILL ALLOW SEAS TO COME DOWN FROM AROUND 5 FT IN
OUTER WATERS TO 2 TO 4 FT BY MORNING ACROSS MOST WATERS. THE SEAS
WILL REMAIN A MIX OF NE SWELL WITH NEARLY A 9 SEC PERIOD AND
LOCALLY WIND DRIVEN SHORTER PERIOD SWELL.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 255 PM SATURDAY...SUNDAY AFTERNOON AND EVENING WILL MARK A
TRANSITION IN WIND DIRECTION AS A SURFACE HIGH PRESENTLY OVER
LAND...SLIPS OFFSHORE AND BRINGS WINDS AROUND WITH A SOUTHERLY
COMPONENT. THIS WILL LIKELY OCCUR SUNDAY AFTERNOON AS THE SEA
BREEZE CIRCULATION HASTENS THE TRANSITION...S-SE WINDS 10-15 KT
SUNDAY AFTERNOON...EASING TO S-SW 5 KT OVERNIGHT SUNDAY. SOUTH
WINDS MONDAY AS THE HIGH HOLDS JUST OFFSHORE OF OUR COAST.
WAVE DIRECTION BOTH SUNDAY AND MONDAY WILL HOLD FROM AN EASTERLY
DIRECTION...WITH GRADUALLY DECREASING WAVE HEIGHTS SUNDAY INTO
MONDAY. SOME NEAR SHORE CHOPPINESS WILL OCCUR SUNDAY AND MONDAY
AFTERNOON...AS THE SEA BREEZE ENHANCES WIND SPEEDS SEVERAL KTS.
LONG TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 255 PM SATURDAY...HIGH PRESSURE EXTENDING ACROSS THE WATERS
THROUGH THE LONG TERM CREATES LIGHT WINDS AND INCREASING SE SWELL.
WINDS OF AROUND 10 KTS WILL PERSIST THROUGH THE PERIOD...AND WILL
HAVE A PREDOMINANT SOUTHERLY COMPONENT WITH ONLY MINOR TEMPORAL
FLUCTUATIONS TO SE OR SW. SINCE THESE WINDS WILL BE LIGHT...THE WAVE
SPECTRUM WILL BE ALMOST ENTIRELY SWELL DOMINATED. A 2FT/8SEC E/SE
SWELL WILL START THE PERIOD...BUILDING TO A 3FT/8SEC SE SWELL AS
RETURN FLOW CONTINUES AROUND HIGH PRESSURE. SEAS WILL BE ONLY 1-2
FT THROUGH WEDNESDAY...BUILDING TO 2-3 FT LATE THURSDAY DUE TO
THE INCREASED SWELL AMPLITUDE.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...RGZ
SHORT TERM...MJC
LONG TERM...JDW
AVIATION...SGL
AREA FORECAST DISCUSSION
NWS RALEIGH NC
308 PM EDT FRI JUN 15 2012
.SYNOPSIS...
HIGH PRESSURE WILL EXTEND SOUTHWARD INTO THE CAROLINAS OVER THE
WEEKEND...WITH CONTINUED BELOW NORMAL TEMPERATURES AND DRY
CONDITIONS. AN UPPER LEVEL RIDGE WILL STRENGTHEN OVER THE CAROLINAS
EARLY NEXT WEEK. NEAR NORMAL TEMPERATURES ARE EXPECTED MONDAY AND
TUESDAY...FOLLOWED BY ABOVE NORMAL TEMPERATURES BY MID WEEK.
&&
.NEAR TERM /THROUGH SATURDAY NIGHT/...
AS OF 1220 PM FRIDAY...
OVERVIEW:
AN UPPER LEVEL RIDGE CENTERED WEST OF THE APPALACHIANS THIS
AFTERNOON WILL BUILD EASTWARD TOWARD THE CAROLINAS TODAY THROUGH
SUNDAY WHILE A STALLED UPPER LEVEL TROUGH/DEVELOPING UPPER LEVEL LOW
MEANDERS OFFSHORE IN VICINITY OF BERMUDA. SYNOPTIC SUBSIDENCE
BETWEEN THESE FEATURES ALONG THE EAST COAST WILL ANCHOR UNSEASONABLY
STRONG HIGH PRESSURE OVER NEW ENGLAND AND THE MID ATLANTIC...WITH
A PERSISTENT SURFACE RIDGE AXIS EXTENDING SOUTHWEST INTO THE
CAROLINAS.
THIS AFTERNOON AND EVENING:
CONTINUED NORTHEAST LOW LEVEL FLOW OFF THE DELMARVA/LABRADOR
CURRENT WILL ONCE AGAIN KEEP TEMPERATURES BELOW NORMAL FOR THIS
TIME OF YEAR. THE PRIMARY FORECAST PROBLEM WILL BE CLOUD COVER.
MODEL GUIDANCE HAS A DIFFICULT TIME WITH ONSHORE FLOW GIVEN THAT
LOW LEVEL MOISTURE AND CLOUD COVER ARE HIGHLY DEPENDENT ON
UPSTREAM /OFFSHORE/ CONDITIONS WHERE OBSERVATIONAL DATA IS
RELATIVELY SPARSE. AS SUCH...MODEL SOLUTIONS VARY WITH REGARD TO
THE AMOUNT OF LOW LEVEL MOISTURE OVER THE EASTERN CAROLINAS TODAY.
THE LATEST VISIBLE SATELLITE IMAGERY INDICATES AT LEAST SCATTERED
CLOUD COVER CAN BE EXPECTED EAST OF HIGHWAY ONE THIS
AFTERNOON...WITH PERIODS OF BROKEN CLOUD COVER MOST LIKELY EAST OF
INTERSTATE 95. BROKEN CLOUD COVER IN THE TRIAD THIS MORNING WAS A
RESULT OF EASTERLY UPSLOPE FLOW OVERNIGHT...AND SHOULD THIN OUT TO
SOME DEGREE IN ASSOCIATION WITH DIURNAL HEATING/MIXING THIS
AFTERNOON. GIVEN CONTINUED SYNOPTIC SUBSIDENCE (ENHANCED BY A 300
MILLIBAR SHORT WAVE EXITING THE CAROLINA COAST AT 16Z) AND A
STRONG MID LEVEL SUBSIDENCE INVERSION IN PLACE...PROBABILITIES FOR
MEASURABLE PRECIP ARE CLOSE TO ZERO PERCENT. HOWEVER...WATER VAPOR
IMAGERY AND RAP DATA INDICATE A SHEAR AXIS (UPSTREAM IN CENTRAL
VIRGINIA AND THE DELMARVA AT 16Z) WILL PUSH SOUTH INTO
CENTRAL/EASTERN NORTH CAROLINA LATER THIS AFTERNOON. THIS FEATURE
JUXTAPOSED WITH RELATIVELY BETTER BOUNDARY LAYER MOISTURE AND WEAK
LOW LEVEL CONVERGENCE EAST OF INTERSTATE 95 COULD RESULT IN AN
ISOLATED LOW TOPPED SHOWER /SPRINKLES/ IN THE SOUTHEAST COASTAL
PLAIN... THOUGH PROBABILITIES REMAIN LOW ENOUGH TO PRECLUDE
MENTION IN THE FORECAST. EXPECT HIGHS GENERALLY IN THE LOWER
80S...OR 79 TO 83F... COOLEST IN THE NORTHEAST COASTAL PLAIN AND
WARMEST IN THE SANDHILLS AND SOUTHWEST PIEDMONT.
TONIGHT:
GIVEN A DRY AND SUBSIDENT COLUMN OVER CENTRAL NORTH CAROLINA...
THE FORECAST WILL REMAIN DRY. PERSISTENT NORTHEAST LOW LEVEL FLOW
WILL LEND SOME AMOUNT OF UNCERTAINTY TO CLOUD COVER OVERNIGHT...
THOUGH THE LATEST MODEL GUIDANCE APPEARS TO KEEP SKIES MOSTLY
CLEAR OVER THE MAJORITY OF CENTRAL NORTH CAROLINA. CONTINUED
UPSLOPE FLOW OVER WESTERN NORTH CAROLINA MAY LEAD TO CONTINUED
CLOUD COVER IN THE TRIAD PRIOR TO MIDNIGHT (BEFORE LOW LEVEL
TRAJECTORIES BECOME LESS FAVORABLE)...WHILE ONSHORE FLOW COULD
ALLOW FOR SOME INCREASE IN CLOUD COVER EAST OF HIGHWAY ONE PRIOR
TO SUNRISE. EXPECT RELATIVELY CHILLY LOWS IN THE MID TO UPPER 50S.
SATURDAY AND SATURDAY NIGHT:
FORECAST REASONING REMAINS MUCH THE SAME FOR SATURDAY AND SATURDAY
NIGHT. ALTHOUGH WEAK UPPER LEVEL DISTURBANCES COULD PROGRESS
SOUTHWARD INTO THE CAROLINAS ON THE EASTERN PERIPHERY OF THE UPPER
LEVEL RIDGE CENTERED WEST OF THE SOUTHERN APPALACHIANS...STRONG
SYNOPTIC SUBSIDENCE COUPLED WITH AN UNSEASONABLY DRY (ALBEIT
MODIFIED MARITIME) AIR MASS AND RESULTING STABLE ATMOSPHERE WILL
PRECLUDE THE POTENTIAL FOR PRECIPITATION. CLOUD COVER REMAINS
SOMEWHAT UNCERTAIN AS DESCRIBED ABOVE...WITH SCATTERED DIURNAL
CUMULUS AND PARTLY CLOUDY SKIES MOST LIKELY IN THE COASTAL PLAIN
DURING PEAK HEATING. WITH RELATIVELY LITTLE CHANGE IN AIR
MASS...EXPECT HIGHS GENERALLY 80 TO 84F...PERHAPS 78 TO 79F IN THE
FAR NORTHEAST COASTAL PLAIN. LOWS SATURDAY NIGHT SIMILAR THOUGH
PERHAPS SLIGHTLY WARMER THAN TONIGHT...UPPER 50S. -VINCENT
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 240 PM...
SURFACE HIGH PRESSURE NOSING SOUTHEAST INTO THE CAROLINA FOOTHILLS
SUNDAY MORNING SHIFTS EAST DURING THE DAY AND LIGHT SOUTH FLOW WILL
DOMINATE MOST OF THIS FORECAST PERIOD. SOME MID AND UPPER LEVEL
CLOUDINESS WITH AFTERNOON CUMULUS DEVELOPING. WITH WEAK SUMMER LIKE
WINDS... LITTLE DYNAMIC FORCING. AFTERNOON DEWPOINTS IN THE MID TO
UPPER 50S WILL PREVENT MOST AIR PARCELS FROM LIFTING FAR OFF THE
GROUND. AN ISOLATED AFTERNOON SHOWER POSSIBLE... MAINLY MONDAY...
BUT AT NO TIME SHOULD RAIN CHANCES EXCEED TEN PERCENT.
AS SURFACE PRESSURES BEGIN TO FALL... 1000 TO 850 MILLIBAR
THICKNESSES RISE... USHERING IN THE BEGINNING OF A WARMING TREND.
AFTERNOON HIGH TEMPERATURES IN THE LOWER 80S SUNDAY... MID 80S
MONDAY. LOW TEMPERATURES IN THE LOWER 60S SUNDAY NIGHT... MID 60S
MONDAY NIGHT.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 305 PM...
SURFACE HIGH PRESSURE IN THE ATLANTIC PERSISTS THROUGH THE PERIOD
WITH WEAK SOUTH TO SOUTHWEST FLOW OVER THE CAROLINAS. LOW LEVEL
THICKNESSES RISE... SENDING HIGH TEMPERATURES FIVE TO EIGHT
DEGREES ABOVE NORMAL. DEWPOINTS RISE INTO THE MID TO UPPER 60S BUT
WINDS THROUGHOUT THE AIR COLUMN CONTINUE WEAK. AFTERNOON MIXING
HEIGHTS SHOULD GENERALLY BE 5000 FEET OR HIGHER WITH AN INVERTED
VEE BOUNDARY LAYER. WIDESPREAD PRECIPITATION APPEARS IMPOSSIBLE...
BUT ISOLATED AFTERNOON CONVECTION A RISK. RAIN CHANCES WILL
CONTINUE BELOW SLIGHT FOR THIS FORECAST PERIOD.
HIGH TEMPERATURES MOSTLY UPPER 80S TUESDAY... THEN LOW TO MID 90S.
LOW TEMPERATURES 64 TO 69.
&&
.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
AS OF 140 PM FRIDAY...
24-HR TAF PERIOD:
VFR CONDITIONS ARE ANTICIPATED THROUGH THE TAF PERIOD...WITH ANY
CEILINGS GENERALLY REMAINING AT 3500 TO 4500 FEET AGL. ALTHOUGH IT
IS POSSIBLE THAT ISOLATED AREAS COULD SEE MVFR CEILINGS FOR A
PERIOD OVERNIGHT...AT THIS TIME PROBABILITIES REMAIN TOO LOW AND
UNCERTAINTY TOO HIGH FOR ANY MENTION WITH THE 18Z TAF ISSUANCE.
LOW LEVEL NORTHEAST FLOW WILL PERSIST THROUGH SATURDAY...WITH
NORTHEAST WINDS AROUND 10 KNOTS THIS AFTERNOON...DECREASING TO 5
KNOT AT SUNSET...THEN INCREASING TO AROUND 10 KNOTS AGAIN BY 15Z
SAT.
SATURDAY NIGHT THROUGH WEDNESDAY:
AN UPPER LEVEL RIDGE WILL BUILD TOWARD THE CAROLINAS FROM THE WEST
OVER THE WEEKEND...THEN STRENGTHEN DIRECTLY OVER THE CAROLINAS AND
MID ATLANTIC NEXT WEEK. ASIDE FROM A CHANCE FOR FOG DURING THE
PREDAWN HOURS EACH MORNING...EXPECT DRY/VFR CONDITIONS THROUGH
THE MIDDLE OF NEXT WEEK. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT
AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS RALEIGH NC
248 PM EDT FRI JUN 15 2012
.SYNOPSIS...
HIGH PRESSURE WILL EXTEND SOUTHWARD INTO THE CAROLINAS OVER THE
WEEKEND...WITH CONTINUED BELOW NORMAL TEMPERATURES AND DRY
CONDITIONS. AN UPPER LEVEL RIDGE WILL STRENGTHEN OVER THE CAROLINAS
EARLY NEXT WEEK. NEAR NORMAL TEMPERATURES ARE EXPECTED MONDAY AND
TUESDAY...FOLLOWED BY ABOVE NORMAL TEMPERATURES BY MID WEEK.
&&
.NEAR TERM /THROUGH SATURDAY NIGHT/...
AS OF 1220 PM FRIDAY...
OVERVIEW:
AN UPPER LEVEL RIDGE CENTERED WEST OF THE APPALACHIANS THIS
AFTERNOON WILL BUILD EASTWARD TOWARD THE CAROLINAS TODAY THROUGH
SUNDAY WHILE A STALLED UPPER LEVEL TROUGH/DEVELOPING UPPER LEVEL LOW
MEANDERS OFFSHORE IN VICINITY OF BERMUDA. SYNOPTIC SUBSIDENCE
BETWEEN THESE FEATURES ALONG THE EAST COAST WILL ANCHOR UNSEASONABLY
STRONG HIGH PRESSURE OVER NEW ENGLAND AND THE MID ATLANTIC...WITH
A PERSISTENT SURFACE RIDGE AXIS EXTENDING SOUTHWEST INTO THE
CAROLINAS.
THIS AFTERNOON/EVENING:
CONTINUED NORTHEAST LOW-LEVEL FLOW OFF THE DELMARVA/LABRADOR CURRENT
WILL ONCE AGAIN KEEP TEMPERATURES BELOW NORMAL FOR THIS TIME OF
YEAR. THE PRIMARY FORECAST PROBLEM WILL BE CLOUD COVER. MODEL
GUIDANCE HAS A DIFFICULT TIME WITH ONSHORE FLOW GIVEN THAT LOW LEVEL
MOISTURE AND CLOUD COVER ARE HIGHLY DEPENDENT ON UPSTREAM
/OFFSHORE/ CONDITIONS WHERE OBSERVATIONAL DATA IS RELATIVELY
SPARSE. AS SUCH...MODEL SOLUTIONS VARY WITH REGARD TO THE AMOUNT
OF LOW LEVEL MOISTURE OVER THE EASTERN CAROLINAS TODAY. THE LATEST
VISIBLE SATELLITE IMAGERY INDICATES AT LEAST SCATTERED CLOUD COVER
CAN BE EXPECTED EAST OF HIGHWAY ONE THIS AFTERNOON...WITH PERIODS
OF BROKEN CLOUD COVER MOST LIKELY EAST OF INTERSTATE 95. BROKEN
CLOUD COVER IN THE TRIAD THIS MORNING WAS A RESULT OF EASTERLY
UPSLOPE FLOW OVERNIGHT...AND SHOULD THIN OUT TO SOME DEGREE IN
ASSOCIATION WITH DIURNAL HEATING/MIXING THIS AFTERNOON. GIVEN
CONTINUED SYNOPTIC SUBSIDENCE (ENHANCED BY A 300 MILLIBAR SHORT
WAVE EXITING THE CAROLINA COAST AT 16Z) AND A STRONG MID LEVEL
SUBSIDENCE INVERSION IN PLACE...PROBABILITIES FOR MEASURABLE
PRECIP ARE CLOSE TO ZERO PERCENT. HOWEVER...WATER VAPOR IMAGERY
AND RAP DATA INDICATE A SHEAR AXIS (UPSTREAM IN CENTRAL VIRGINIA
AND THE DELMARVA AT 16Z) WILL PUSH SOUTH INTO CENTRAL/EASTERN
NORTH CAROLINA LATER THIS AFTERNOON. THIS FEATURE JUXTAPOSED WITH
RELATIVELY BETTER BOUNDARY LAYER MOISTURE AND WEAK LOW LEVEL
CONVERGENCE EAST OF INTERSTATE 95 COULD RESULT IN AN ISOLATED LOW
TOPPED SHOWER /SPRINKLES/ IN THE SOUTHEAST COASTAL PLAIN... THOUGH
PROBABILITIES REMAIN LOW ENOUGH TO PRECLUDE MENTION IN THE
FORECAST. EXPECT HIGHS GENERALLY IN THE LOWER 80S...OR 79 TO
83F... COOLEST IN THE NORTHEAST COASTAL PLAIN AND WARMEST IN THE
SANDHILLS/SOUTHWEST PIEDMONT.
TONIGHT:
GIVEN A DRY/SUBSIDENT COLUMN OVER CENTRAL NORTH CAROLINA... THE
FORECAST WILL REMAIN DRY. PERSISTENT NORTHEAST LOW LEVEL FLOW
WILL LEND SOME AMOUNT OF UNCERTAINTY TO CLOUD COVER OVERNIGHT...
THOUGH THE LATEST MODEL GUIDANCE APPEARS TO KEEP SKIES MOSTLY
CLEAR OVER THE MAJORITY OF CENTRAL NORTH CAROLINA. CONTINUED
UPSLOPE FLOW OVER WESTERN NORTH CAROLINA MAY LEAD TO CONTINUED
CLOUD COVER IN THE TRIAD PRIOR TO MIDNIGHT (BEFORE LOW LEVEL
TRAJECTORIES BECOME LESS FAVORABLE)...WHILE ONSHORE FLOW COULD
ALLOW FOR SOME INCREASE IN CLOUD COVER EAST OF HIGHWAY ONE PRIOR
TO SUNRISE. EXPECT RELATIVELY CHILLY LOWS IN THE MID TO UPPER 50S.
SATURDAY AND SATURDAY NIGHT:
FORECAST REASONING REMAINS MUCH THE SAME FOR SATURDAY AND SATURDAY
NIGHT. ALTHOUGH WEAK UPPER LEVEL DISTURBANCES COULD PROGRESS
SOUTHWARD INTO THE CAROLINAS ON THE EASTERN PERIPHERY OF THE UPPER
LEVEL RIDGE CENTERED WEST OF THE SOUTHERN APPALACHIANS...STRONG
SYNOPTIC SUBSIDENCE COUPLED WITH AN UNSEASONABLY DRY (ALBEIT
MODIFIED MARITIME) AIR MASS AND RESULTING STABLE ATMOSPHERE WILL
PRECLUDE THE POTENTIAL FOR PRECIPITATION. CLOUD COVER REMAINS
SOMEWHAT UNCERTAIN AS DESCRIBED ABOVE...WITH SCATTERED DIURNAL
CUMULUS AND PARTLY CLOUDY SKIES MOST LIKELY IN THE COASTAL PLAIN
DURING PEAK HEATING. WITH RELATIVELY LITTLE CHANGE IN AIR
MASS...EXPECT HIGHS GENERALLY 80 TO 84F...PERHAPS 78 TO 79F IN THE
FAR NORTHEAST COASTAL PLAIN. LOWS SAT NIGHT SIMILAR THOUGH PERHAPS
SLIGHTLY WARMER THAN TONIGHT...UPPER 50S. -VINCENT
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 240 PM...
SURFACE HIGH PRESSURE NOSING SOUTHEAST INTO THE CAROLINA FOOTHILLS
SUNDAY MORNING SHIFTS EAST DURING THE DAY AND LIGHT SOUTH FLOW WILL
DOMINATE MOST OF THIS FORECAST PERIOD. SOME MID AND UPPER LEVEL
CLOUDINESS WITH AFTERNOON CUMULUS DEVELOPING. WITH WEAK SUMMER LIKE
WINDS... LITTLE DYNAMIC FORCING. AFTERNOON DEWPOINTS IN THE MID TO
UPPER 50S WILL PREVENT MOST AIR PARCELS FROM LIFTING FAR OFF THE
GROUND. AN ISOLATED AFTERNOON SHOWER POSSIBLE... MAINLY MONDAY...
BUT AT NO TIME SHOULD RAIN CHANCES EXCEED TEN PERCENT.
AS SURFACE PRESSURES BEGIN TO FALL... 1000 TO 850 MILLIBAR
THICKNESSES RISE... USHERING IN THE BEGINNING OF A WARMING TREND.
AFTERNOON HIGH TEMPERATURES IN THE LOWER 80S SUNDAY... MID 80S
MONDAY. LOW TEMPERATURES IN THE LOWER 60S SUNDAY NIGHT... MID 60S
MONDAY NIGHT.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 315 AM FRIDAY...
HEAT IS EXPECTED TO RETURN BY THE MIDDLE OF NEXT WEEK.
THE UPPER LEVEL LOW OFF THE EAST COAST IS FORECAST TO REMAIN
STATIONARY OR EVEN RETROGRADE SLIGHTLY EARLY NEXT WEEK...THEN BEGIN
TO LIFT NORTHWARD BY MIDWEEK....WHILE A STRONG RIDGE DEVELOPS ACROSS
THE SOUTHEAST AND MID ATLANTIC STATES. AS THE OFFSHORE LOW
WEAKENS... THERE IS VERY GOOD MODEL AGREEMENT ON A 5940 METER 500
MILLIBAR HIGH DEVELOPING OVER THE NORTH CAROLINA AND VIRGINIA BY
MIDWEEK. THIS WILL PUSH LOW LEVEL THICKNESSES WELL ABOVE 1405
METERS... WHICH IS NORMAL FOR THE BEGINNING OF SUMMER. THE ECMWF
IS THE WARMER OF THE MEDIUM RANGE MODELS WITH 1000 TO 850 MILLIBAR
THICKNESSES REACHING 1440 METERS BY AND 850 MILLIBAR TEMPERATURES
OF 22 CELSIUS BY THURSDAY. THUS...THERE IS INCREASING CONFIDENCE
IN HIGHS REACHING THE MID 90S BY MIDWEEK...WITH UPPER 90S NOT OUT
OF THE QUESTION. MODELS DO NOT SHOW A MUCH MOISTURE RETURN BENEATH
THE UPPER RIDGE HOWEVER...WHICH WOULD HELP KEEP DEWPOINTS DOWN IN
THE LOWER 60S AND LIMIT HEAT INDICES FROM REACHING EXCESSIVE
VALUES. THERE HAVE ONLY BEEN A FEW 90 DEGREE DAYS SO FAR THIS
YEAR..SO THIS WILL BE THE HOTTEST STRETCH TO DATE. DIURNAL
CONVECTION SHOULD BE SPARSE BENEATH THE RIDGE...AND OVERNIGHT LOWS
WILL INCH UP INTO THE MID 60S.
&&
.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
AS OF 140 PM FRIDAY...
24-HR TAF PERIOD:
VFR CONDITIONS ARE ANTICIPATED THROUGH THE TAF PERIOD...WITH ANY
CEILINGS GENERALLY REMAINING AT 3500 TO 4500 FEET AGL. ALTHOUGH IT
IS POSSIBLE THAT ISOLATED AREAS COULD SEE MVFR CEILINGS FOR A
PERIOD OVERNIGHT...AT THIS TIME PROBABILITIES REMAIN TOO LOW AND
UNCERTAINTY TOO HIGH FOR ANY MENTION WITH THE 18Z TAF ISSUANCE.
LOW LEVEL NORTHEAST FLOW WILL PERSIST THROUGH SATURDAY...WITH
NORTHEAST WINDS AROUND 10 KNOTS THIS AFTERNOON...DECREASING TO 5
KNOT AT SUNSET...THEN INCREASING TO AROUND 10 KNOTS AGAIN BY 15Z
SAT.
SATURDAY NIGHT THROUGH WEDNESDAY:
AN UPPER LEVEL RIDGE WILL BUILD TOWARD THE CAROLINAS FROM THE WEST
OVER THE WEEKEND...THEN STRENGTHEN DIRECTLY OVER THE CAROLINAS AND
MID ATLANTIC NEXT WEEK. ASIDE FROM A CHANCE FOR FOG DURING THE
PREDAWN HOURS EACH MORNING...EXPECT DRY/VFR CONDITIONS THROUGH
THE MIDDLE OF NEXT WEEK. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT
LONG TERM...SMITH
AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS RALEIGH NC
138 PM EDT FRI JUN 15 2012
.SYNOPSIS...
HIGH PRESSURE WILL EXTEND SOUTHWARD INTO THE CAROLINAS OVER THE
WEEKEND...WITH CONTINUED BELOW NORMAL TEMPERATURES AND DRY
CONDITIONS. AN UPPER LEVEL RIDGE WILL STRENGTHEN OVER THE CAROLINAS
EARLY NEXT WEEK. NEAR NORMAL TEMPERATURES ARE EXPECTED MONDAY AND
TUESDAY...FOLLOWED BY ABOVE NORMAL TEMPERATURES BY MID-WEEK.
&&
.NEAR TERM /THROUGH SATURDAY NIGHT/...
AS OF 1220 PM FRIDAY...
OVERVIEW:
AN UPPER LEVEL RIDGE CENTERED WEST OF THE APPALACHIANS THIS
AFTERNOON WILL BUILD EASTWARD TOWARD THE CAROLINAS TODAY THROUGH
SUNDAY WHILE A STALLED UPPER LEVEL TROUGH/DEVELOPING UPPER LEVEL LOW
MEANDERS OFFSHORE IN VICINITY OF BERMUDA. SYNOPTIC SUBSIDENCE
BETWEEN THESE FEATURES ALONG THE EAST COAST WILL ANCHOR UNSEASONABLY
STRONG HIGH PRESSURE OVER NEW ENGLAND AND THE MID-ATLANTIC...WITH A
PERSISTENT SFC RIDGE AXIS EXTENDING SOUTHWEST INTO THE CAROLINAS.
THIS AFTERNOON/EVENING:
CONTINUED NORTHEAST LOW-LEVEL FLOW OFF THE DELMARVA/LABRADOR CURRENT
WILL ONCE AGAIN KEEP TEMPERATURES BELOW NORMAL FOR THIS TIME OF
YEAR. THE PRIMARY FORECAST PROBLEM WILL BE CLOUD COVER. MODEL
GUIDANCE HAS A DIFFICULT TIME WITH ONSHORE FLOW GIVEN THAT LOW-LEVEL
MOISTURE AND CLOUD COVER ARE HIGHLY DEPENDENT ON UPSTREAM /OFFSHORE/
CONDITIONS WHERE OBSERVATIONAL DATA IS RELATIVELY SPARSE. AS
SUCH...MODEL SOLUTIONS VARY W/REGARD TO THE AMOUNT OF LOW-LEVEL
MOISTURE OVER THE EASTERN CAROLINAS TODAY. THE LATEST VIS SAT
IMAGERY INDICATES AT LEAST SCATTERED CLOUD COVER CAN BE EXPECTED
EAST OF HWY 1 THIS AFTERNOON...WITH PERIODS OF BROKEN CLOUD COVER
MOST LIKELY EAST OF I-95. BROKEN CLOUD COVER IN THE TRIAD THIS
MORNING WAS A RESULT OF EASTERLY UPSLOPE FLOW OVERNIGHT...AND SHOULD
THIN OUT TO SOME DEGREE IN ASSOC/W DIURNAL HEATING/MIXING THIS
AFTERNOON. GIVEN CONTINUED SYNOPTIC SUBSIDENCE (ENHANCED BY AN H3
SHORTWAVE EXITING THE CAROLINA COAST AT 16Z) AND A STRONG MID-LEVEL
SUBSIDENCE INVERSION IN PLACE...PROBABILITIES FOR MEASURABLE PRECIP
ARE CLOSE TO 0%. HOWEVER...WV IMAGERY AND RAP DATA INDICATE A SHEAR
AXIS (UPSTREAM IN CENTRAL VA AND THE DELMARVA AT 16Z) WILL PUSH
SOUTH INTO CENTRAL/EASTERN NC LATER THIS AFTERNOON. THIS FEATURE
JUXTAPOSED WITH RELATIVELY BETTER BOUNDARY LAYER MOISTURE AND WEAK
LOW-LEVEL CONVERGENCE EAST OF I-95 COULD RESULT IN AN ISOLD
LOW-TOPPED SHOWER /SPRINKLES/ IN THE SOUTHEAST COASTAL PLAIN...
THOUGH PROBS REMAIN LOW ENOUGH TO PRECLUDE MENTION IN THE FORECAST.
EXPECT HIGHS GENERALLY IN THE LOWER 80S...OR 79-83F... COOLEST IN
THE NE COASTAL PLAIN AND WARMEST IN THE SANDHILLS/SW PIEDMONT.
TONIGHT:
GIVEN A DRY/SUBSIDENT COLUMN OVER CENTRAL NC...THE FORECAST WILL
REMAIN DRY. PERSISTENT NORTHEAST LOW-LEVEL FLOW WILL LEND SOME
AMOUNT OF UNCERTAINTY TO CLOUD COVER OVERNIGHT...THOUGH THE LATEST
MODEL GUIDANCE APPEARS TO KEEP SKIES MOSTLY CLEAR OVER THE MAJORITY
OF CENTRAL NC. CONTINUED UPSLOPE FLOW OVER WESTERN NC MAY LEAD TO
CONTINUED CLOUD COVER IN THE TRIAD PRIOR TO MIDNIGHT (BEFORE
LOW-LEVEL TRAJECTORIES BECOME LESS FAVORABLE)...WHILE ONSHORE FLOW
COULD ALLOW FOR SOME INCREASE IN CLOUD COVER EAST OF HWY 1 PRIOR TO
SUNRISE. EXPECT RELATIVELY CHILLY LOWS IN THE MID/UPPER 50S.
SATURDAY AND SATURDAY NIGHT:
FORECAST REASONING REMAINS MUCH THE SAME FOR SAT/SAT NIGHT. ALTHOUGH
WEAK UPPER LEVEL DISTURBANCES COULD PROGRESS SOUTHWARD INTO THE
CAROLINAS ON THE EASTERN PERIPHERY OF THE UPPER LEVEL RIDGE CENTERED
WEST OF THE SOUTHERN APPALACHIANS...STRONG SYNOPTIC SUBSIDENCE
COUPLED WITH AN UNSEASONABLY DRY (ALBEIT MODIFIED MARITIME) AIRMASS
AND RESULTING STABLE ATMOSPHERE WILL PRECLUDE THE POTENTIAL FOR
PRECIPITATION. CLOUD COVER REMAINS SOMEWHAT UNCERTAIN AS DESCRIBED
ABOVE...WITH SCATTERED DIURNAL CU AND PARTLY CLOUDY SKIES MOST
LIKELY IN THE COASTAL PLAIN DURING PEAK HEATING. WITH RELATIVELY
LITTLE CHANGE IN AIRMASS...EXPECT HIGHS GENERALLY 80-84F...PERHAPS
78-79F IN THE FAR NE COASTAL PLAIN. LOWS SAT NIGHT SIMILAR THOUGH
PERHAPS SLIGHTLY WARMER THAN TONIGHT...UPPER 50S. -VINCENT
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 315 AM FRIDAY...
AN UPPER LEVEL LOW WILL CONTINUE TO SPIN OFF THE EAST COAST
SUNDAY...WHILE HEIGHTS BEGIN TO BUILD FROM THE GULF COAST ACROSS THE
MIDWEST. THE BUILDING UPPER RIDGE WILL HELP KEEP A SHORTWAVE
CROSSING THE NORTHERN US WELL TO THE NORTH OF OUR AREA LATE SUNDAY
AND MONDAY...AND LIMITED MOISTURE RETURN WILL KEEP THE MORE UNSTABLE
AIRMASS WEST OF THE MOUNTAINS. THUS...THE GFS MAY BE TOO AGGRESSIVE
IN DEVELOPING CONVECTION AS FAR SOUTH AS THE NORTHWEST PIEDMONT ON
MONDAY. INSTEAD...WE WILL SHOW A PERIOD OF ENHANCED MID AND HIGH
CLOUDS ON MONDAY AS MOISTURE DRIFTS TOP THE RIDGE. THE SURFACE RIDGE
EXTENDING ALONG THE EAST COAST IS FORECAST TO WEAKEN AND SHIFT
OFFSHORE DURING THIS PERIOD...AND 1000-850MB THICKNESSES ARE PROGGED
TO INCH BACK TOWARD 1400M SUNDAY AND MONDAY...LEADING TO A
MODERATION OF HIGHS BACK INTO THE LOW TO MID 80S. LOWS WILL ALSO
BEGIN TO INCREASE BACK INTO THE UPPER 50S TO NEAR 60.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 315 AM FRIDAY...
HEAT IS EXPECTED TO RETURN BY THE MIDDLE OF NEXT WEEK.
THE UPPER LEVEL LOW OFF THE EAST COAST IS FORECAST TO REMAIN
STATIONARY OR EVEN RETROGRADE SLIGHTLY EARLY NEXT WEEK...THEN BEGIN
TO LIFT NORTHWARD BY MIDWEEK....WHILE A STRONG RIDGE DEVELOPS ACROSS
THE SOUTHEAST AND MID ATLANTIC STATES. AS THE OFFSHORE LOW
WEAKENS... THERE IS VERY GOOD MODEL AGREEMENT ON A 5940M 500MB HIGH
DEVELOPING OVER THE NC AND VA BY MIDWEEK. THIS WILL PUSH LOW LEVEL
THICKNESSES WELL ABOVE 1405M...WHICH IS NORMAL FOR THE BEGINNING
OF SUMMER. THE ECMWF IS THE WARMER OF THE MEDIUM RANGE MODELS WITH
1000-850MB THICKNESSES REACHING 1440M BY AND 850MB TEMPS OF 22C BY
THURSDAY. THUS...THERE IS INCREASING CONFIDENCE IN HIGHS REACHING
THE MID 90S BY MIDWEEK...WITH UPPER 90S NOT OUT OF THE QUESTION.
MODELS DO NOT SHOW A MUCH MOISTURE RETURN BENEATH THE UPPER
RIDGE HOWEVER...WHICH WOULD HELP KEEP DEWPOINTS DOWN IN THE LOWER
60S AND LIMIT HEAT INDICES FROM REACHING EXCESSIVE VALUES. THERE
HAVE ONLY BEEN A FEW 90 DEGREE DAYS SO FAR THIS YEAR..SO THIS WILL
BE THE HOTTEST STRETCH TO DATE. DIURNAL CONVECTION SHOULD BE SPARSE
BENEATH THE RIDGE...AND OVERNIGHT LOWS WILL INCH UP INTO THE MID 60S.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 140 PM FRIDAY...
24-HR TAF PERIOD:
VFR CONDITIONS ARE ANTICIPATED THROUGH THE TAF PERIOD...WITH ANY
CEILINGS GENERALLY REMAINING AT 3500-4500 FT AGL. ALTHOUGH IT IS
POSSIBLE THAT ISOLATED AREAS COULD SEE MVFR CEILINGS FOR A PERIOD
OVERNIGHT...AT THIS TIME PROBABILITIES REMAIN TOO LOW AND
UNCERTAINTY TOO HIGH FOR ANY MENTION WITH THE 18Z TAF ISSUANCE.
LOW-LEVEL NORTHEAST FLOW WILL PERSIST THROUGH SATURDAY...WITH
NORTHEAST WINDS AROUND 10 KT THIS AFTERNOON...DECREASING TO 5 KT AT
SUNSET...THEN INCREASING TO AROUND 10 KT AGAIN BY 15Z SAT.
SATURDAY NIGHT THROUGH WEDNESDAY:
AN UPPER LEVEL RIDGE WILL BUILD TOWARD THE CAROLINAS FROM THE WEST
OVER THE WEEKEND...THEN STRENGTHEN DIRECTLY OVER THE CAROLINAS AND
MID-ATLANTIC NEXT WEEK. ASIDE FROM A CHANCE FOR FOG DURING THE
PRE-DAWN HOURS EACH MORNING...EXPECT DRY/VFR CONDITIONS THROUGH THE
MIDDLE OF NEXT WEEK. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT
SHORT TERM...SMITH
LONG TERM...SMITH
AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1220 PM EDT FRI JUN 15 2012
.SYNOPSIS...
HIGH PRESSURE WILL EXTEND SOUTHWARD INTO THE CAROLINAS OVER THE
WEEKEND...WITH CONTINUED BELOW NORMAL TEMPERATURES AND DRY
CONDITIONS. AN UPPER LEVEL RIDGE WILL STRENGTHEN OVER THE CAROLINAS
EARLY NEXT WEEK. NEAR NORMAL TEMPERATURES ARE EXPECTED MONDAY AND
TUESDAY...FOLLOWED BY ABOVE NORMAL TEMPERATURES BY MID-WEEK.
&&
.NEAR TERM /THROUGH SATURDAY NIGHT/...
AS OF 1220 PM FRIDAY...
OVERVIEW:
AN UPPER LEVEL RIDGE CENTERED WEST OF THE APPALACHIANS THIS
AFTERNOON WILL BUILD EASTWARD TOWARD THE CAROLINAS TODAY THROUGH
SUNDAY WHILE A STALLED UPPER LEVEL TROUGH/DEVELOPING UPPER LEVEL LOW
MEANDERS OFFSHORE IN VICINITY OF BERMUDA. SYNOPTIC SUBSIDENCE
BETWEEN THESE FEATURES ALONG THE EAST COAST WILL ANCHOR UNSEASONABLY
STRONG HIGH PRESSURE OVER NEW ENGLAND AND THE MID-ATLANTIC...WITH A
PERSISTENT SFC RIDGE AXIS EXTENDING SOUTHWEST INTO THE CAROLINAS.
THIS AFTERNOON/EVENING:
CONTINUED NORTHEAST LOW-LEVEL FLOW OFF THE DELMARVA/LABRADOR CURRENT
WILL ONCE AGAIN KEEP TEMPERATURES BELOW NORMAL FOR THIS TIME OF
YEAR. THE PRIMARY FORECAST PROBLEM WILL BE CLOUD COVER. MODEL
GUIDANCE HAS A DIFFICULT TIME WITH ONSHORE FLOW GIVEN THAT LOW-LEVEL
MOISTURE AND CLOUD COVER ARE HIGHLY DEPENDENT ON UPSTREAM /OFFSHORE/
CONDITIONS WHERE OBSERVATIONAL DATA IS RELATIVELY SPARSE. AS
SUCH...MODEL SOLUTIONS VARY W/REGARD TO THE AMOUNT OF LOW-LEVEL
MOISTURE OVER THE EASTERN CAROLINAS TODAY. THE LATEST VIS SAT
IMAGERY INDICATES AT LEAST SCATTERED CLOUD COVER CAN BE EXPECTED
EAST OF HWY 1 THIS AFTERNOON...WITH PERIODS OF BROKEN CLOUD COVER
MOST LIKELY EAST OF I-95. BROKEN CLOUD COVER IN THE TRIAD THIS
MORNING WAS A RESULT OF EASTERLY UPSLOPE FLOW OVERNIGHT...AND SHOULD
THIN OUT TO SOME DEGREE IN ASSOC/W DIURNAL HEATING/MIXING THIS
AFTERNOON. GIVEN CONTINUED SYNOPTIC SUBSIDENCE (ENHANCED BY AN H3
SHORTWAVE EXITING THE CAROLINA COAST AT 16Z) AND A STRONG MID-LEVEL
SUBSIDENCE INVERSION IN PLACE...PROBABILITIES FOR MEASURABLE PRECIP
ARE CLOSE TO 0%. HOWEVER...WV IMAGERY AND RAP DATA INDICATE A SHEAR
AXIS (UPSTREAM IN CENTRAL VA AND THE DELMARVA AT 16Z) WILL PUSH
SOUTH INTO CENTRAL/EASTERN NC LATER THIS AFTERNOON. THIS FEATURE
JUXTAPOSED WITH RELATIVELY BETTER BOUNDARY LAYER MOISTURE AND WEAK
LOW-LEVEL CONVERGENCE EAST OF I-95 COULD RESULT IN AN ISOLD
LOW-TOPPED SHOWER /SPRINKLES/ IN THE SOUTHEAST COASTAL PLAIN...
THOUGH PROBS REMAIN LOW ENOUGH TO PRECLUDE MENTION IN THE FORECAST.
EXPECT HIGHS GENERALLY IN THE LOWER 80S...OR 79-83F... COOLEST IN
THE NE COASTAL PLAIN AND WARMEST IN THE SANDHILLS/SW PIEDMONT.
TONIGHT:
GIVEN A DRY/SUBSIDENT COLUMN OVER CENTRAL NC...THE FORECAST WILL
REMAIN DRY. PERSISTENT NORTHEAST LOW-LEVEL FLOW WILL LEND SOME
AMOUNT OF UNCERTAINTY TO CLOUD COVER OVERNIGHT...THOUGH THE LATEST
MODEL GUIDANCE APPEARS TO KEEP SKIES MOSTLY CLEAR OVER THE MAJORITY
OF CENTRAL NC. CONTINUED UPSLOPE FLOW OVER WESTERN NC MAY LEAD TO
CONTINUED CLOUD COVER IN THE TRIAD PRIOR TO MIDNIGHT (BEFORE
LOW-LEVEL TRAJECTORIES BECOME LESS FAVORABLE)...WHILE ONSHORE FLOW
COULD ALLOW FOR SOME INCREASE IN CLOUD COVER EAST OF HWY 1 PRIOR TO
SUNRISE. EXPECT RELATIVELY CHILLY LOWS IN THE MID/UPPER 50S.
SATURDAY AND SATURDAY NIGHT:
FORECAST REASONING REMAINS MUCH THE SAME FOR SAT/SAT NIGHT. ALTHOUGH
WEAK UPPER LEVEL DISTURBANCES COULD PROGRESS SOUTHWARD INTO THE
CAROLINAS ON THE EASTERN PERIPHERY OF THE UPPER LEVEL RIDGE CENTERED
WEST OF THE SOUTHERN APPALACHIANS...STRONG SYNOPTIC SUBSIDENCE
COUPLED WITH AN UNSEASONABLY DRY (ALBEIT MODIFIED MARITIME) AIRMASS
AND RESULTING STABLE ATMOSPHERE WILL PRECLUDE THE POTENTIAL FOR
PRECIPITATION. CLOUD COVER REMAINS SOMEWHAT UNCERTAIN AS DESCRIBED
ABOVE...WITH SCATTERED DIURNAL CU AND PARTLY CLOUDY SKIES MOST
LIKELY IN THE COASTAL PLAIN DURING PEAK HEATING. WITH RELATIVELY
LITTLE CHANGE IN AIRMASS...EXPECT HIGHS GENERALLY 80-84F...PERHAPS
78-79F IN THE FAR NE COASTAL PLAIN. LOWS SAT NIGHT SIMILAR THOUGH
PERHAPS SLIGHTLY WARMER THAN TONIGHT...UPPER 50S. -VINCENT
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 315 AM FRIDAY...
AN UPPER LEVEL LOW WILL CONTINUE TO SPIN OFF THE EAST COAST
SUNDAY...WHILE HEIGHTS BEGIN TO BUILD FROM THE GULF COAST ACROSS THE
MIDWEST. THE BUILDING UPPER RIDGE WILL HELP KEEP A SHORTWAVE
CROSSING THE NORTHERN US WELL TO THE NORTH OF OUR AREA LATE SUNDAY
AND MONDAY...AND LIMITED MOISTURE RETURN WILL KEEP THE MORE UNSTABLE
AIRMASS WEST OF THE MOUNTAINS. THUS...THE GFS MAY BE TOO AGGRESSIVE
IN DEVELOPING CONVECTION AS FAR SOUTH AS THE NORTHWEST PIEDMONT ON
MONDAY. INSTEAD...WE WILL SHOW A PERIOD OF ENHANCED MID AND HIGH
CLOUDS ON MONDAY AS MOISTURE DRIFTS TOP THE RIDGE. THE SURFACE RIDGE
EXTENDING ALONG THE EAST COAST IS FORECAST TO WEAKEN AND SHIFT
OFFSHORE DURING THIS PERIOD...AND 1000-850MB THICKNESSES ARE PROGGED
TO INCH BACK TOWARD 1400M SUNDAY AND MONDAY...LEADING TO A
MODERATION OF HIGHS BACK INTO THE LOW TO MID 80S. LOWS WILL ALSO
BEGIN TO INCREASE BACK INTO THE UPPER 50S TO NEAR 60.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 315 AM FRIDAY...
HEAT IS EXPECTED TO RETURN BY THE MIDDLE OF NEXT WEEK.
THE UPPER LEVEL LOW OFF THE EAST COAST IS FORECAST TO REMAIN
STATIONARY OR EVEN RETROGRADE SLIGHTLY EARLY NEXT WEEK...THEN BEGIN
TO LIFT NORTHWARD BY MIDWEEK....WHILE A STRONG RIDGE DEVELOPS ACROSS
THE SOUTHEAST AND MID ATLANTIC STATES. AS THE OFFSHORE LOW
WEAKENS... THERE IS VERY GOOD MODEL AGREEMENT ON A 5940M 500MB HIGH
DEVELOPING OVER THE NC AND VA BY MIDWEEK. THIS WILL PUSH LOW LEVEL
THICKNESSES WELL ABOVE 1405M...WHICH IS NORMAL FOR THE BEGINNING
OF SUMMER. THE ECMWF IS THE WARMER OF THE MEDIUM RANGE MODELS WITH
1000-850MB THICKNESSES REACHING 1440M BY AND 850MB TEMPS OF 22C BY
THURSDAY. THUS...THERE IS INCREASING CONFIDENCE IN HIGHS REACHING
THE MID 90S BY MIDWEEK...WITH UPPER 90S NOT OUT OF THE QUESTION.
MODELS DO NOT SHOW A MUCH MOISTURE RETURN BENEATH THE UPPER
RIDGE HOWEVER...WHICH WOULD HELP KEEP DEWPOINTS DOWN IN THE LOWER
60S AND LIMIT HEAT INDICES FROM REACHING EXCESSIVE VALUES. THERE
HAVE ONLY BEEN A FEW 90 DEGREE DAYS SO FAR THIS YEAR..SO THIS WILL
BE THE HOTTEST STRETCH TO DATE. DIURNAL CONVECTION SHOULD BE SPARSE
BENEATH THE RIDGE...AND OVERNIGHT LOWS WILL INCH UP INTO THE MID 60S.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 740 AM FRIDAY...
APART FROM BRIEF IFR/LIFR CIGS AND MVFR VSBYS AT INT/GSO FOR AN HOUR
OR TWO THIS MORNING... VFR CONDITIONS WILL DOMINATE ACROSS CENTRAL
NC THROUGH TODAY AND TONIGHT... AS SURFACE HIGH PRESSURE CENTERED
OVER SOUTHEAST CANADA NOSES SOUTHWARD THROUGH CENTRAL NC. A SHOT OF
MOIST ATLANTIC LOW LEVEL AIR FROM THE NORTHEAST WILL BRING SCATTERED
CLOUDS BASED BELOW 3 THOUSAND FEET THROUGH DAYBREAK... AND PATCHY
CLOUDS BELOW 5 HUNDRED FEET WILL BRIEFLY BECOME BROKEN IN COVERAGE
IN THE TRIAD... BUT ELSEWHERE THESE CLOUDS WILL BE FEW. VFR CIGS
BASED AT 4-6 THOUSAND FEET ARE POSSIBLE THIS AFTERNOON WITH DAYTIME
HEATING... BUT THESE CLOUDS WILL DISSIPATE DURING THE EARLY EVENING.
NORTHEAST WINDS SUSTAINED AT 8-13 KTS (LIGHTER AT WESTERN AIRPORTS
SUCH AS INT/GSO AND STRONGER AT EASTERN AIRPORTS LIKE RWI/FAY) WILL
OCCASIONALLY GUST TO AROUND 15 KTS (INT/GSO) TO 18-23 KTS
(RDU/RWI/FAY) FROM MID MORNING UNTIL MID TO LATE AFTERNOON...
FOLLOWED BY A WEAKENING OF NORTHEAST WINDS TO UNDER 10 KTS THIS
EVENING.
LOOKING BEYOND 12Z TONIGHT... HIGH PRESSURE AT THE SURFACE AND ALOFT
WILL COVER THE REGION FOR THE NEXT SEVERAL DAYS... BRINGING A
LENGTHY PERIOD OF MAINLY VFR CONDITIONS. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT
SHORT TERM...SMITH
LONG TERM...SMITH
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
1011 AM CDT FRI JUN 15 2012
.DISCUSSION...WILL NEED TO WATCH AREA OF PRECIP ACROSS SOUTHWEST
NORTH DAKOTA AS IT APPROACHES THE FA THIS AFTERNOON. WEAK WAVE
SEEN ON WATER VAPOR IMAGERY COULD PROVIDE SHOWERS TO THE WESTERN
FA THIS AFTERNOON. THESE SHOWERS IN AREA OF HIGHER 700MB
MOISTURE...WHICH 12Z RUC INDICATES WILL ADVECT INTO THE WESTERN FA
BY 21Z. HOWEVER...SFC-850MB MOISTURE REMAINS RELATIVELY DRY AND
WOULD LIKELY BE SPRINKLES IF ANYTHING. CURRENT FORECAST HAS HIGHER
POPS AFTER 00Z AND THIS STILL REASONABLE. NO CHANGES NEEDED TO
CURRENT FORECAST.
&&
.AVIATION...EXPECT VFR CONDITIONS AT ALL TAF AIRFIELDS THROUGH AT
LEAST 00 UTC WITH ONLY PERIODS OF CIRRUS AND AFTERNOON CU IN THE 5
TO 6 KFT LAYER. LIGHT WESTERLY WIND WILL SHIFT TO THE SOUTH LATER
THIS AFTERNOON. SHOWERS AND THUNDERSTORMS WILL INCREASE FROM WEST
TO EAST THIS EVENING AND OVERNIGHT AS A COLD FRONT SWEEPS ACROSS
THE REGION. MODELS HINT AT SOME LOWER CEILINGS AFTER 06 UTC...BUT
CONFIDENCE IS LOW...SO WILL SHOW A GENERAL DOWNWARD TREND WITHIN
THE VFR RANGE AT THIS TIME. WILL INTRODUCE PRECIPITATION AT KDVL
STARTING AT 05 UTC AND MOVE IT EASTWARD THROUGH THE NIGHT...NOT
IMPACTING KBJI UNTIL AFTER 12 UTC SATURDAY.
&&
.PREV DISCUSSION... /ISSUED 348 AM CDT FRI JUN 15 2012/
SHORT TERM...TODAY THROUGH SUNDAY NIGHT
PRIMARY FORECAST CHALLENGES WILL BE PRECIPITATION CHANCES AND
SEVERE POTENTIAL TONIGHT THROUGH THE WEEKEND. GFS/NAM/ECMWF/GEM
ARE IN GOOD AGREEMENT...BUT WILL LEAN TOWARD SLIGHTLY FASTER GFS/
NAM SOLUTIONS GIVEN PROGRESSIVE FLOW ALOFT.
TODAY WILL BE MOSTLY SUNNY AND WARM AS SURFACE HIGH PRESSURE MOVES
ACROSS THE NORTHERN PLAINS. WITH THE EXCEPTION OF SOME CIRRUS BLOW
OFF FROM CENTRAL PLAINS CONVECTION AND AFTERNOON THERMAL CU IN THE
5 TO 6 KFT LAYER...EXPECT ABUNDANT SUNSHINE WITH HIGH TEMPERATURES
CLIMBING INTO THE LOWER 80S MOST LOCATIONS. LIGHT WEST WIND WILL
GRADUALLY SHIFT TO THE SOUTH AS SURFACE RIDGE AXIS MOVES INTO
EASTERN MN.
SHOWER AND THUNDERSTORM CHANCES INCREASE FROM WEST TO EAST THIS
EVENING AND OVERNIGHT AS VORT MAX CURRENTLY NEAR THE SOUTHERN
BRITISH COLUMBIA/ALBERTA BORDER MOVES INTO SOUTHEAST SASKATCHEWAN
BY 12 UTC SATURDAY. PWATS INCREASE TO NEAR 1.5 INCHES ALONG AND
AHEAD OF ADVANCING FRONTAL BOUNDARY WITH ENHANCED LIFT FROM RIGHT
ENTRANCE REGION OF 300 HPA 90 TO 100 KT JET. LIMITING FACTORS WILL
BE INSTABILITY WITH MLCAPE GENERALLY 500 J/KG OR LESS AND A DIFFUSE
850 HPA JET NEAR 30 KTS. DO NOT ANTICIPATE SEVERE CONVECTION AT
THIS TIME WITH RAINFALL AMOUNTS GENERALLY A HALF INCH OR LESS.
LOCALLY HIGHER AMOUNTS UP TO AN INCH ARE POSSIBLE WITH STRONGER
STORMS.
CONVECTION WILL MOVE INTO NORTHWEST AND WEST CENTRAL MN BY SATURDAY
MORNING AND THEN PROGRESS RAPIDLY EASTWARD THROUGH THE REMAINDER
OF THE DAY. SHOULD SEE BREAKS OF SUN ALONG AND WEST OF THE VALLEY
BY AFTERNOON WITH INCREASING WESTERLY WIND AND SOME GUSTS TO 25 MPH.
LINGERING PRECIPITATION WILL MOVE OUT OF THE FORECAST AREA BY
SATURDAY EVENING. TEMPERATURES WILL BE COOLER THAN TODAY WITH
HIGHS IN THE MID 70S.
SATURDAY NIGHT INTO SUNDAY MORNING WILL BE DRY...BUT THUNDER
CHANCES RETURN ONCE AGAIN BY SUNDAY AFTERNOON INTO THE OVERNIGHT
HOURS AS A BROAD UPPER TROUGH MOVES INTO THE NORTHERN ROCKIES.
SEVERE CONVECTIVE PARAMETERS IN BETTER ALIGNMENT SUNDAY AFTERNOON
WITH A WESTERLY 100 KT 300 HPA JET...SOUTHERLY 40 KT 850 HPA
JET...MLCAPE UP TO 2000 J/KG AND PWATS APPROACHING 2 INCHES. MOST
FAVORED AREA FOR SEVERE THUNDERSTORMS WILL BE ACROSS EASTERN ND
AND THIS IS WELL HIGHLIGHTED IN LATEST SPC DAY 3 CONVECTIVE
OUTLOOK. PRIMARY THREATS ARE LARGE HAIL AND DAMAGING WIND. HIGH
TEMPERATURES WILL CLIMB BACK INTO THE 80S WITH A BREEZY SOUTHERLY
WIND AHEAD OF ANY CONVECTION THAT DEVELOPS. PEOPLE WITH OUTDOOR
FATHER/S DAY PLANS SHOULD MONITOR THE LATEST FORECASTS AND
STATEMENTS FOR THE MOST UP TO DATE INFORMATION.
LONG TERM...MONDAY THROUGH THURSDAY
THE FAIRLY ACTIVE WEATHER PATTERN SHOULD CONTINUE WITH SW FLOW ALOFT
TRANSITIONING TO MORE W/NW FLOW BY NEXT THU. THE BEST CHANCES FOR
SHOWERS AND STORMS SHOULD BE EARLY MONDAY...THEN AGAIN ON WED.
WILL STILL MAINTAIN LOWER POPS THOUGH EVEN FOR TUE WITH SOME MODEL
TIMING DIFFERENCES...ALTHOUGH MOST AREAS SHOULD BE DRY TUE THEN
AGAIN THU. TEMPS SHOULD START OUT NEAR NORMAL THEN COOL BELOW
NORMAL TOWARDS THE END OF NEXT WEEK.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
TG
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
946 PM EDT SAT JUN 16 2012
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN NEAR THE ATLANTIC COAST THROUGH THE
WEEKEND. AN UPPER LEVEL DISTURBANCE MAY MOVE INTO NW OHIO BY
SUNDAY MORNING. THIS WILL BE FOLLOWED BY A WEAKENING COLD FRONT
THAT WILL STALL OVER CENTRAL OHIO. THE FRONT WILL DISSIPATE BY
TUESDAY AS HIGH PRESSURE STRENGTHENS OVER THE MIDDLE ATLANTIC.
&&
.NEAR TERM /THROUGH SUNDAY/...
MADE MINOR ADJUSTMENTS TO TIMING OF HOURLY POPS AND WX THROUGH THE
OVERNIGHT BASED ON RADAR TRENDS AND RECENT HRRR MODEL RUNS.
CONVECTION THAT MOVED INTO NW OH EARLIER THIS EVENING QUICKLY
DETERIORATED...AND FOCUS WILL BE ON SHOWERS AND THUNDERSTORMS OVER
IL. EXPECTING THIS AREA OF SHRA/TS TO MOVE EAST OVERNIGHT...BUT
THEN ADDITIONAL DEVELOPMENT AHEAD OF THIS INITIAL CLUSTER OF
ACTIVITY WITH SHRA/TS MOVING INTO WRN ZONES TOL-FDY AROUND
07-09Z...THEN CONTINUE TO GRADUALLY MOVE EAST TOWARD CLE-MFD BY
12Z. ZONES INDICATING MAINLY LIKELY WORDING GIVEN HIGH POPS LATE
IN THE OVERNIGHT PERIOD ESPECIALLY EAST OF SANDUSKY-MARION LINE.
MADE MINOR TEMP ADJUSTMENTS ON LOWS WITH MAINLY MID 60S ACROSS THE
EASTERN HALF OF THE AREA WITH LOWER 60S FOR NW PA. PREVIOUS
DISCUSSION BELOW.
OVERNIGHT HOWEVER MODELS CONTINUE TO SHOW COLD FRONT APPROACHING
FROM THE NORTHWEST WITH A SHORT WAVE AND FURTHER INCREASING
MOISTURE. BY MORNING EXPECT SHOWERS AND THUNDERSTORMS TO HAVE
REACHED INTO NWRN OHIO SO WILL GO WITH LIKELY POPS FAR
NORTHWEST...AND CHANCE/SLIGHT CHANCE ELSEWHERE.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
SUNDAY CONTINUES TO LOOK LIKE SHOWERS AND THUNDERSTORMS WILL BE
LIKELY ALTHOUGH DO NOT EXPECT A COMPLETE WASHOUT OF THE DAY WITH
AT LEAST PARTLY SUNNY SKIES BETWEEN THUNDERSTORMS. WILL GO WITH
LIKELY POPS ALL COUNTIES. TIMING APPEARS TO FAVOR THE MORNING WEST
AND AFTERNOON EAST BASED ON FRONTAL POSITION AND PROGGED MOISTURE.
BY 00Z MONDAY DEEPER MOISTURE WILL BE EAST OF THE AREA. WILL CARRY
A CHANCE INTO THE FIRST HALF OF THE NIGHT EAST HALF BUT AFTER
MIDNIGHT WILL DROP TO A SLIGHT CHANCE GIVEN LACK OF FORCING.
MONDAY INTO TUESDAY THE UPPER RIDGE BUILDS BACK ACROSS THE OHIO
VALLEY. AFTERNOON CAPES BOTH DAYS APPROACH 1500 J/KG ON THE NAM12
THINKING THAT THE UPPER RIDGE WILL SUPPRESS CONVECTION FOR THE MOST
PART. WILL HAVE LOW CHANCE POPS AND SLIGHT CHANCE POPS FOR MONDAY
BUT WILL KEEP DRY TUESDAY. TEMPS NEAR 90 BOTH MONDAY AND TUESDAY
SHOULD BE COMMON.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
A STALLED UPPER RIDGE OVER THE EAST THIRD OF THE COUNTRY WILL
PROVIDE DRY AND HOT CONDITIONS FOR THE AREA THROUGH MID WEEK. MODELS
A LITTLE FASTER WITH THE NEXT WEAK FRONT MOVING IT THROUGH THURSDAY
NIGHT INTO FRIDAY MORNING. WENT WITH THE GFS WHICH WAS SLIGHTLY
SLOWER THAN THE CURRENT ECMWF.
&&
.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
TOUGH FORECAST THIS EVENING WITH TIMING OF PRECIP THE MAIN
CHALLENGE. SOME CONVECTION CONTINUES TO MOVE INTO NW OH THIS
EVENING. LATEST GUIDANCE SUGGESTS THAT THIS ACTIVITY WILL FIZZLE
IN A COUPLE OF HOURS. WILL GIVE A BRIEF MENTION AT KTOL AND KFDY
BUT IT OTHERWISE WILL BE DRY TILL LATE TONIGHT. GUIDANCES
SUGGESTING THAT ANOTHER LINE OF STORMS WILL DEVELOP TO THE WEST OF
THE AREA LATE THIS EVENING AND MOVE INTO NW OH AFTER MIDNIGHT.
GIVEN TIME OF DAY WILL NOT MENTION THUNDER BUT WILL TRY TO TIME A
2 OR 3 HOUR WINDOW OF SHOWERS ACROSS THE AREA TOWARD DAYBREAK.
MORE SHOWERS AND STORMS ARE LIKELY ON SUNDAY. RIGHT NOW IT APPEARS
THE BEST CHANCES FOR THIS WILL BE IN THE AFTERNOON. SOME HAZE IS
POSSIBLE OVERNIGHT AND SUNDAY MORNING. SE TO S FLOW WILL INCREASE
ON SUNDAY WITH SOME GUSTS TO 30 KNOTS POSSIBLE DURING THE
AFTERNOON.
.OUTLOOK...NON VFR POSSIBLE MAINLY IN CONVECTION SUNDAY AND
MONDAY.
&&
.MARINE...
SOUTH FLOW OVER THE LAKE WILL INCREASE TO 10 TO 20 KNOTS SUNDAY THEN
VEER A LITTLE MORE TOWARD SOUTHWEST SUNDAY NIGHT AS A WEAK COLD
FRONT MOVES ACROSS THE LAKE. A SOUTH TO SOUTHWEST FLOW WILL REMAIN
OVER THE LAKE THROUGH MID WEEK AS RIDGE OF HIGH PRESSURE REMAINS
OVER THE LAKE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TK
NEAR TERM...ABE/TK
SHORT TERM...TK
LONG TERM...DJB
AVIATION...KUBINA
MARINE...DJB
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1103 AM EDT FRI JUN 15 2012
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL STAY CENTERED OVER THE REGION
RIGHT THROUGH THIS WEEKEND. THIS WEATHER FEATURE WILL PROVIDE
SEVERAL MORE DAYS OF DRY AND SEASONABLY WARM WEATHER FOR ALL OF
CENTRAL PENNSYLVANIA. HOWEVER...A LOW LEVEL EASTERLY FLOW WILL
BRING PERIODS OF CLOUDINESS...ESPECIALLY OVER EASTERN SECTIONS OF
THE STATE. THE NEXT WIDESPREAD CHANCE FOR RAIN IN THE FORM OF
SCATTERED SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A WARM FRONT
WILL START OVER THE WESTERN HALF OF THE STATE SUNDAY NIGHT...AND
CONTINUE INTO CENTRAL AND EASTERN PARTS OF PENNSYLVANIA ON MONDAY.
TEMPERATURES WILL REMAIN NEAR NORMAL TODAY THROUGH
SUNDAY...FOLLOWED BY MUCH WARMER AND MORE HUMID CONDITIONS NEXT
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
STRATOCU HAS MORPHED INTO MORE-VERTICALLY DEVELOPED AND CELLULAR
DIURNAL CU EXCEPT IN THE POCONOS...WHERE SOME MEASURE OF STABILITY
REMAINS. HOWEVER...THAT STABILITY SHOULD DROP AND THERE WILL BE
JUST A VERY SLIGHT CHC OF A SHOWER POPPING UP OVER THE EASTERN
SECTIONS LIKE THE HIGHER ELEVS OF THE POCONOS AND ENDLESS MTS. THE
LIMITING FACTOR IS THE STRONG SUBSIDENCE INVERSION...WHICH WILL
LIMIT HOW TALL THE CLOUDS WILL GET. LATEST HRRR AND RUC AS WELL
AS 00Z NAM4KM SHOW CAPES OVER 500J/KG AND GENERATE SOME CONV
PRECIP IN THE HIGHER HILLS OF THE EAST/NORTHEAST THIS AFTN AND
LAST INTO EARLY EVENING. WILL KEEP POPS 20PCT OR BELOW...BUT
MENTION SLIGHT CHC FOR THE NE.
LLVL TROUGH AND AREAS OF THETA-E CONVERGENCE WILL FOCUS BKN-OVC
CLOUDS ACROSS THE SUSQ VALLEY AND POINTS EAST TONIGHT...WHILE MUCH
OF CENTRAL AND WESTERN PENN SEES PARTLY CLOUDY CONDITIONS. LOWS AT
SUNRISE SATURDAY WILL BE IN THE MID 50S TO LOWER 60S.
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
POSITIVE TILT...LLVL RIDGE WILL SHIFT TO THE EAST COAST BY EARLY
SUNDAY...HELPING TO CUTOFF MUCH OF THE MOISTURE FROM THE MID
ATLANTIC COAST. IT WILL STAY COMFORTABLE THROUGH SATURDAY NIGHT AS
PRECIP WATER VALUES WILL STAY MAINLY UNDER ONE INCH. WARMER TEMPS...
ALONG WITH A SHARP RISE IN PWATS AND RELATIVE HUMIDITY WILL FOLLOW
FOR LATE SAT NIGHT...RIGHT THROUGH MONDAY.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
THE SHARP UPPER LEVEL RIDGE EXTENDING FROM THE MID MISSISSIPPI
VALLEY TO THE LOWER GREAT LAKES WILL TEMPORARILY BREAK DOWN LATE
THIS WEEKEND THROUGH EARLY NEXT WEEK AS SHORTWAVE ENERGY CARVES ITS
WAY FROM THE UPPER MIDWEST...TO THE LOWER GREAT LAKES AND UPR OHIO
VALLEY REGION BY 00Z MONDAY.
A WEAK...DYING COLD FRONT WILL MOVE INTO THE FCST AREA LATE SUNDAY
NIGHT AND MONDAY...PRECEDED BY A RATHER ILL-DEFINED NORTH/SOUTH WARM
FRONT ALONG THE SUSQ MAINSTEM. STEEPEST MID-LEVEL LAPSE RATES /A
LITTLE OVER 6C/KM/ AND POCKET OF ASSOCIATED -4 TO -5C SFC BASED
LIFTED INDICES WILL BECOME CONCENTRATED OVER THE WESTERN HALF OF THE
STATE LATE SUNDAY/SUNDAY NIGHT. THIS WILL PRODUCE SCATTERED SHOWERS
AND PERHAPS A FEW TSRA...MAINLY ACROSS THE NW MTNS.
PRECIPITABLE WATER VALUES WILL SURGE TO AROUND 1.5 INCHES MONDAY AND
TUESDAY ACROSS PENNSYLVANIA /OR +1-2 STANDARD DEVIATIONS/. 00Z EC
AND THE 03Z SREF ARE THE QUICKEST TO BRING PRECIP TO THE REGION LATE
SUNDAY AFTERNOON AND NIGHT WHILE THE 00Z ECMWF IS ABOUT 150 NM TOO
SLOW.
THE UPPER RIDGE QUICKLY AMPLIFIES ACROSS THE OHIO VALLEY LATE MONDAY
NIGHT THROUGH TUESDAY AND EXTENDS THROUGH CENTRAL PENN. 700 MB TEMPS
WILL CLIMB TO 8-10C... LEADING TO A STRING OF VERY WARM AND MORE
HUMID DAYS TO CLOSE OUT THE MIDDLE AND LATTER PART OF NEXT WEEK.
ALTHOUGH I CAN/T RULE OUT A SLOW MOVING/PULSE TSRA DEVELOPING DURING
THIS PERIOD...THEY SHOULD BE FEW AND FAR BETWEEN.
TEMPS WILL REACH THE MID/UPR 80S WEDDNESDAY AND THURSDAY OVER THE
CENTRAL MTNS AND LAURELS HIGHLANDS...WHILE THE COMMUNITIES
THROUGHOUT THE SUSQ CREST ABOVE THE 90 DEGREE MARK BOTH DAYS.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
LOW CLOUDS EXPANDING AS DIURNAL CU...BUT STRONG INVERSION AROUND
5KFT WILL LIMIT THE VERTICAL EXTENT OF THE CLOUDS. VFR SHOULD
PREVAIL AS THE CLOUD BASES ARE LIFTING OUT OF MVFR ATTM.
HOWEVER...A FEW CLOUDS COULD GET TALL ENOUGH OVER THE NERN MTS
/TO NE OF IPT AND MDT/ TO MAKE A STRAY SHOWER. NO THUNDER EXPECTED
AT THIS POINT.
ANOTHER DECENT DAY EXPECTED ON SAT. DID ADD IN A FEW LOWER CLDS
AND FOG EARLY. MOST OF SUN SHOULD BE OK. PERHAPS A FEW SHOWERS
AND STORMS LATER SUNDAY ACROSS THE FAR WEST.
OUTLOOK...
MON-TUE...ISOLD PM THUNDERSTORM IMPACTS POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/GARTNER
AVIATION...DANGELO/MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
844 AM EDT FRI JUN 15 2012
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL STAY CENTERED OVER THE REGION
RIGHT THROUGH THIS WEEKEND. THIS WEATHER FEATURE WILL PROVIDE
SEVERAL MORE DAYS OF DRY...SEASONABLY WARM WEATHER FOR ALL OF
CENTRAL PENNSYLVANIA. HOWEVER...A LOW LEVEL EASTERLY FLOW
WILL BRING PERIODS OF CLOUDINESS...ESPECIALLY OVER EASTERN SECTIONS
OF THE STATE. THE NEXT WIDESPREAD CHANCE FOR RAIN IN THE FORM OF
SCATTERED SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A WARM FRONT
WILL START OVER THE WESTERN HALF OF THE STATE SUNDAY NIGHT...AND
CONTINUE INTO CENTRAL AND EASTERN PARTS OF PENNSYLVANIA ON
MONDAY. TEMPERATURES WILL REMAIN NEAR NORMAL TODAY THROUGH
SUNDAY...FOLLOWED BY MUCH WARMER AND MORE HUMID CONDITIONS NEXT
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
A PERSISTENT...MOIST LLVL ESE FLOW ORIGINATING OVER THE WRN
ATLANTIC WILL SPREAD VARYING AMOUNTS STRATOCU ACROSS THE CENTRAL
AND EASTERN PORTIONS OF OUR CWA TODAY...WITH JUST A VERY SLIGHT
CHC OF A SHOWER POPPING UP OVER THE EASTERN SECTIONS LIKE THE
HIGHER ELEVS OF THE POCONOS AND ENDLESS MTS. DIURNAL CU ALREADY
POPPING WITH LLVL MSTR HIGH AND TRAPPED JUST BENEATH THE
INVERSION. SEVERAL HUNDRED J/KG OF SFC BASED CAPE IN THE EASTERN
MTS WILL LEAD TO A MORE WIDESPREAD AND VERTICALLY DEVELOPED CU
FIELD THERE AND THE POSS FOR A SHOWER. LATEST HRRR AND RUC AS WELL
AS 00Z NAM4KM GENERATE SOME CONV PRECIP THERE THIS AFTN.
AFTERNOON TEMPS TODAY WILL DISPLAY A VERY NARROW 3-4F RANGE...AND
TOP OUT IN THE MID TO UPPER 70S.
LLVL TROUGH AND AREAS OF THETA-E CONVERGENCE WILL FOCUS BKN-OVC
CLOUDS ACROSS THE SUSQ VALLEY AND POINTS EAST TONIGHT...WHILE MUCH
OF CENTRAL AND WESTERN PENN SEES PARTLY CLOUDY CONDITIONS. LOWS AT
SUNRISE SATURDAY WILL BE IN THE MID 50S TO LOWER 60S.
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
POSITIVE TILT...LLVL RIDGE WILL SHIFT TO THE EAST COAST BY EARLY
SUNDAY...HELPING TO CUTOFF MUCH OF THE MOISTURE FROM THE MID
ATLANTIC COAST. IT WILL STAY COMFORTABLE THROUGH SATURDAY NIGHT AS
PRECIP WATER VALUES WILL STAY MAINLY UNDER ONE INCH. WARMER TEMPS...
ALONG WITH A SHARP RISE IN PWATS AND RELATIVE HUMIDITY WILL FOLLOW
FOR LATE SAT NIGHT...RIGHT THROUGH MONDAY.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
THE SHARP UPPER LEVEL RIDGE EXTENDING FROM THE MID MISSISSIPPI
VALLEY TO THE LOWER GREAT LAKES WILL TEMPORARILY BREAK DOWN LATE
THIS WEEKEND THROUGH EARLY NEXT WEEK AS SHORTWAVE ENERGY CARVES ITS
WAY FROM THE UPPER MIDWEST...TO THE LOWER GREAT LAKES AND UPR OHIO
VALLEY REGION BY 00Z MONDAY.
A WEAK...DYING COLD FRONT WILL MOVE INTO THE FCST AREA LATE SUNDAY
NIGHT AND MONDAY...PRECEDED BY A RATHER ILL-DEFINED NORTH/SOUTH WARM
FRONT ALONG THE SUSQ MAINSTEM. STEEPEST MID-LEVEL LAPSE RATES /A
LITTLE OVER 6C/KM/ AND POCKET OF ASSOCIATED -4 TO -5C SFC BASED
LIFTED INDICES WILL BECOME CONCENTRATED OVER THE WESTERN HALF OF THE
STATE LATE SUNDAY/SUNDAY NIGHT. THIS WILL PRODUCE SCATTERED SHOWERS
AND PERHAPS A FEW TSRA...MAINLY ACROSS THE NW MTNS.
PRECIPITABLE WATER VALUES WILL SURGE TO AROUND 1.5 INCHES MONDAY AND
TUESDAY ACROSS PENNSYLVANIA /OR +1-2 STANDARD DEVIATIONS/. 00Z EC
AND THE 03Z SREF ARE THE QUICKEST TO BRING PRECIP TO THE REGION LATE
SUNDAY AFTERNOON AND NIGHT WHILE THE 00Z ECMWF IS ABOUT 150 NM TOO
SLOW.
THE UPPER RIDGE QUICKLY AMPLIFIES ACROSS THE OHIO VALLEY LATE MONDAY
NIGHT THROUGH TUESDAY AND EXTENDS THROUGH CENTRAL PENN. 700 MB TEMPS
WILL CLIMB TO 8-10C... LEADING TO A STRING OF VERY WARM AND MORE
HUMID DAYS TO CLOSE OUT THE MIDDLE AND LATTER PART OF NEXT WEEK.
ALTHOUGH I CAN/T RULE OUT A SLOW MOVING/PULSE TSRA DEVELOPING DURING
THIS PERIOD...THEY SHOULD BE FEW AND FAR BETWEEN.
TEMPS WILL REACH THE MID/UPR 80S WEDDNESDAY AND THURSDAY OVER THE
CENTRAL MTNS AND LAURELS HIGHLANDS...WHILE THE COMMUNITIES
THROUGHOUT THE SUSQ CREST ABOVE THE 90 DEGREE MARK BOTH DAYS.
&&
.AVIATION /13Z FRIDAY THROUGH TUESDAY/...
EVENING SHIFT HAD THE RIGHT IDEA WITH SOME LOWER CLDS. THEY HAD
LOWER CLDS FORMING AROUND 08Z. BY 09Z WE HAD SOME. SO FAR...NOT
MUCH FOG. ANYWAY...EXPECT LWR CLDS TO BREAK UP AND EVERYONE BE VFR
AGAIN BY 15Z IF NOT SOONER. DID HOLD ONTO LWR CLDS A LITTLE LONGER
ON THIS TAF PACKAGE.
AFT THIS...EXPECT VFR CONDITIONS TODAY.
ANOTHER DECENT DAY EXPECTED ON SAT. DID ADD IN A FEW LOWER CLDS
AND FOG EARLY.
MOST OF SUN SHOULD BE OK. PERHAPS A FEW SHOWERS AND STORMS LATER
SUNDAY ACROSS THE FAR WEST.
OUTLOOK...
SAT...NO SIG WX EXPECTED.
SUN...ISOLD PM THUNDERSTORM IMPACTS POSS W MTNS.
MON-TUE...ISOLD PM THUNDERSTORM IMPACTS POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/GARTNER
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
144 AM EDT FRI JUN 15 2012
.SYNOPSIS...
A LARGE...SLOW MOVING AREA OF HIGH PRESSURE WILL STAY IN CONTROL
OF OUR LOCAL WEATHER...AND PROVIDE SEVERAL MORE DAYS OF DRY
WEATHER IN CENTRAL PENNSYLVANIA. HOWEVER...EASTERLY WINDS BETWEEN
THIS HIGH PRESSURE SYSTEM CENTERED OVER QUEBEC CANADA...AND LOW
PRESSURE MEANDERING WELL TO THE EAST OF THE OUTER BANKS OF NORTH
CAROLINA...COULD BRING LOW CLOUDS TO SOUTHEASTERN AND CENTRAL
PARTS OF THE STATE AT TIMES OVERNIGHT INTO SATURDAY. TEMPERATURES
WILL REMAIN NEAR NORMAL WITH A GRADUAL MODERATION EXPECTED THROUGH
THE UPCOMING WEEKEND.
&&
.NEAR TERM /UNTIL 7 AM THIS MORNING/...
A PERSISTENT ESE LLVL FETCH OF MOIST AIR FROM THE WRN ATLANTIC
WILL LIKELY KEEP VARIABLE AMOUNTS OF STRATOCU IN PLACE ACROSS THE
SOUTHERN AND EASTERN PORTIONS OF OUR CWA OVERNIGHT.
ACROSS THE CENTRAL AND NRN COUNTIES OF THE CWA...THE
FORMATION AND EVENTUAL EXTENT OF LLVL CLOUDS IS MORE UNCERTAIN.
23Z RUC INDICATES SLIGHTLY HIGHER RH VALUES DEVELOPING WITHIN THE
SERLY UPSLOPE FLOW ACROSS THE LAURELS AND NCENT MTNS. UPDATED THE
GRIDDED SKY COVER TO REFLECT AN INCREASE IN LOW CLOUDS LATE
TONIGHT...AND THE ZONE TEXT WILL VARY BETWEEN PARTLY AND MOSTLY
CLOUDY ACROSS THIS PORTION OF THE CWA.
PATCHY FOG WILL FORM VERY EARLY FRIDAY THROUGHOUT THE NRN MTN
VALLEYS WHERE THE AIR/WATER TEMP WILL BE NEAR 20F.
SFC WIND WILL BE LIGHT AND VARIABLE OVERNIGHT WITHIN THE MIDDLE OF
A RIDGE OF HIGH PRESSURE. SFC DEWPOINTS IN THE 50S /TO AROUND 60F
IN THE SUSQ VALLEY/...AND NUMERICAL GUIDANCE SUGGEST THAT MIN
TEMPS AT DAYBREAK FRIDAY WILL BE SEVERAL DEG F HIGHER THAN EARLY
THIS MORNING.
&&
.SHORT TERM /7 AM THIS MORNING THROUGH 6 PM SATURDAY/...
PERSISTENT EASTERLY FLOW OFF THE ATLANTIC WILL CONTINUE TO MAKE
THE FORECAST PROBLEM OF THE PERIOD. NAM/GFS SOUNDINGS DO INDICATE
A LIFTING AND MIXING TO THE LAYER OF MOISTURE THEY SHOW IN THE
MORNING. THUS...WILL DECREASE THE CLOUD COVER IN THE
MORNING...BUT SLOWEST IN THE CENTRAL AREAS. THIS SHOULD RESULT IN
MOSTLY SUNNY SKIES BEFORE DIURNAL CU RETURNS FOR THE AFTN...ESP IN
THE NERN MTS. WHILE BOTH GFS AND NAM GENERATE WEAK/ISOLD SHRA IN
THE NERN MTS...WILL KEEP IT DRY FOR NOW. AM SKEPTICAL THAT ANY CU
COULD GROW TALL ENOUGH TO PRECIPITATE UNDER THIS RIDGING. THE SFC
RIDGE OVERHEAD OR JUST OVER ERN HALF OF PA WILL KEEP THE FLOW
SERLY. FRI HIGH TEMPS WILL BE SIMILAR TO THURSDAY AFTERNOONS AND
AGAIN RANGE THROUGH THE MID70S TO 80F THROUGHOUT CENTRAL PA.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
AN UPPER RIDGE IS FORECAST TO BE BUILDING INTO THE EASTERN U.S. BY
THE START OF THE PERIOD AND DOMINATE THE ENTIRE FORECAST PERIOD.
NOT UNTIL TOWARDS THE END OF THE PERIOD THAT NORTHERN STREAM
ENERGY BRINGS A UPPER TROF INTO THE EASTERN GREAT LAKES THAT COULD
BRING A FRONT INTO THE FORECAST AREA.
THE UPPER LOW OVER THE NRN ATLANTIC REMAINS IN PLAY AND...SIMILAR
TO TODAY AND FRIDAY...ANY LOW LEVEL SE NIGHTTIME FLOW SHOULD BACK
IN FRIDAY NIGHT/EARLY SATURDAY MORNING. THIS SHOULD ALLOW STRATOCU
ALONG THE LOWER SUSQ...BUT SHOULD DISSIPATE SHORTLY AFTER SUNRISE
GIVEN MIXING AND SUBSIDENCE. EXPECT DAYTIME SKIES TO BE MAINLY
CLEAR AS WELL THANKS TO A LARGE SFC HIGH SITTING OVERHEAD ALONG
WITH THE RIDGE AXIS STAYING JUST TO OUR WEST.
TEMPS SHOULD NOT BE MUCH ABOVE OR BELOW NORMAL FOR MOST OF THE
PERIOD...THOUGH BY THE MIDDLE OF NEXT WEEK A STRONG TEMPERATURE
ANOMALY COULD ALLOW FOR WARMER THAN NORMAL SFC HIGHS.
AFTERNOON/POPCORN SHOWERS DO BECOME POSSIBLE AS THE RIDGE AXIS
SHIFTS BY THE MIDDLE OF NEXT WEEK. MODEL TIMING AND CONSENSUS
DIFFERS ENOUGH TO KEEP POPS LOW.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
RIDGE OF HIGH PRESSURE OVER PA SUPPLYING VFR CONDS AND LIGHT WINDS
LATE THIS EVENING. HOWEVER...POTENTIAL AVIATION CONCERN OVERNIGHT
IS MOIST SE FLOW COMBINED WITH RADIATIONAL COOLING COULD PRODUCE A
PERIOD OF LOW CIGS OR FOG. AT THIS POINT...CONFIDENCE NOT HIGH
ENOUGH TO FCST IFR ANYWHERE. HOWEVER...IT/S A DEFINITE POSSIBILITY
BTWN 09Z-12Z.
ANY LOW CLOUDS/FOG SHOULD DISSIPATE QUICKLY AFTER SUNRISE...AS
HEATING FROM STRONG MID-JUNE SUN MIXES OUT LOW LVL MOISTURE.
WITH HIGH PRES RIDGE REMAINING OVR THE AREA...THERE IS A HIGH
CONFIDENCE OF VFR AND LIGHT WINDS FOR THE REST OF TODAY.
ANOTHER DECENT DAY EXPECTED ON SAT. MOST OF SUN SHOULD BE OK.
PERHAPS A FEW SHOWERS AND STORMS LATER SUNDAY ACROSS THE FAR
WEST.
OUTLOOK...
SAT...NO SIG WX EXPECTED.
SUN...ISOLD PM THUNDERSTORM IMPACTS POSS W MTNS.
MON-TUE...ISOLD PM THUNDERSTORM IMPACTS POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...DANGELO
LONG TERM...DEVOIR/GARTNER
AVIATION...FITZGERALD/MARTIN
AREA FORECAST DISCUSSION...CORRECTED
NWS FORT WORTH TX
118 PM CDT FRI JUN 15 2012
.AVIATION...
CONCERNS...POTENTIAL FOR THUNDER THIS AFTERNOON AND MVFR CIGS
POSSIBLE EARLY SATURDAY MORNING.
A CHANCE FOR THUNDERSTORMS CONTINUES THIS AFTERNOON AT THE DFW
AIRPORTS BUT WILL NOT MENTION THUNDER IN THE KACT TAF AS THE BEST
CHANCES WILL BE NORTH AND EAST OF THE AIRPORT. SCATTERED
THUNDERSTORM ACTIVITY IS EXPECTED TO DEVELOP THROUGH THE AFTERNOON
AS A REMNANT DISTURBANCE FROM LAST NIGHT/S CONVECTION MOVES ALONG
THE RED RIVER. THINK THE BEST TIMING FOR STORMS TO AFFECT THE DFW
TERMINALS IS BETWEEN 20-00Z. SOME OF THE STORMS COULD BE STRONG OR
SEVERE WITH A THREAT FOR LIGHTNING...HAIL...AND GUSTY WINDS.
VFR CONDITIONS ARE EXPECTED TO PREVAIL FOR MUCH OF THE EVENING BUT
THERE IS SOME CONCERN THAT ADDITIONAL RAIN/STORMS MAY DEVELOP
OVERNIGHT. CONFIDENCE IS NOT OVERLY HIGH IN THIS SCENARIO...THUS
WILL NOT MENTION THUNDER OVERNIGHT AT THIS TIME. THERE IS ALSO THE
POTENTIAL FOR MVFR CIGS TO DEVELOP AGAIN TONIGHT. THE CONVECTION
THIS AFTERNOON COULD AFFECT WHERE THE CIGS DEVELOP BUT THE
ATMOSPHERE HAS AMPLE MOISTURE FOR MVFR STRATUS DEVELOPMENT. WITH A
HIGHER POTENTIAL AT KACT...WILL KEEP THE MVFR CIGS AT KACT TONIGHT
BUT ADJUST THE METROPLEX TAFS TO MENTION A SCT020 DECK EARLY
SATURDAY MORNING.
82/JLD
&&
.UPDATE...
ISOLATED SHOWERS AND THUNDERSTORMS CONTINUE LATE THIS MORNING
EAST OF A GAINESVILLE TO STEPHENVILLE LINE. A MCV NORTHWEST OF THE
METROPLEX WILL MOVE EAST THIS AFTERNOON...WITH THE DEEPEST
MOISTURE ACROSS THE EAST. THE BEST CHANCES OF SHOWERS AND
THUNDERSTORMS THIS AFTERNOON AND EVENING WILL BE OVER THE
NORTHERN AND EASTERN ZONES WHERE WE HAVE PLACED THE HIGHEST POPS
OF 30-40 PERCENT. THE STORMS THAT DEVELOP WILL HAVE THE
POTENTIAL TO BECOME SEVERE...PRODUCING LARGE HAIL...DAMAGING
WINDS...FREQUENT CLOUD TO GROUND LIGHTNING AND HEAVY RAIN.
58
&&
.PREV DISCUSSION... /ISSUED 330 AM CDT FRI JUN 15 2012/
MANY MODELS CONTINUE TO OVER-STABILIZE THE ATMOSPHERE...AND ONCE
AGAIN THE RESULT IS THAT THE ATMOSPHERE RETAINS ENOUGH
INSTABILITY TO SUPPORT CONVECTION. THE SHORT WAVE FEATURES
ASSOCIATED WITH THESE SYSTEMS ARE WEAK...AND IT MAY BE THAT THE
SMOOTHING SCHEMES USED IN MODEL INITIATION ARE DESTROYING THESE
FEATURES THAT ARE PRODUCING WEATHER.
FOR TODAY...THE TTU WRF AND 00Z GFS COMPLETELY MISSED THE ONGOING
CONVECTION. THE HRRR IS NOT AVAILABLE. THE RAP/RUC FAILED TO
ADVECT THE STORMS INTO OUR AREA. OUN WRF AND NCEP 4KM WRF BOTH
FORECAST THE NOCTURNAL CONVECTION TO CONTINUE INTO NORTH TEXAS.
THE NAM PRODUCED NO PRECIPITATION TODAY...BUT CROSS SECTION
ANALYSIS SHOWS INSTABILITY AND MOISTURE ABOVE THE MORNING
INVERSION AND SO IT DOES SUPPORT THE POTENTIAL FOR CONVECTION.
ANOTHER FACTOR IS THE MCV THAT IS CURRENTLY CENTERED JUST WEST OF
FREDERICK AND SHOULD TRACK ACROSS SOUTHERN OKLAHOMA. ANY FORCING
FOR LIFT GENERATED BY THIS FEATURE WILL LIKELY NOT BE RESOLVED IN
THIS MORNING/S MODELS. IT MAY BE THAT WEDNESDAY AFTERNOON/S MCV
THAT TRACKED SIMILARLY TO THIS ONE HAD AN INFLUENCE ON THE NORTH
TEXAS CONVECTION THAT PRODUCED THE LARGE HAIL. THUS I HAVE KEPT
POPS ACROSS THE ENTIRE CWA THIS MORNING AND THE EASTERN THIRD
THIS AFTERNOON. WITH DEW POINTS IN THE LOW TO MID 70S...IT WILL
NOT TAKE MUCH FORCING TO DESTABILIZE THIS ATMOSPHERE.
I CONTINUED THE LOW POPS IN THE SOUTHEAST FOR SATURDAY
AFTERNOON...THEN IT APPEARS THAT NORTH TEXAS WILL REMAIN DRY
THROUGH MONDAY. THE TROPICAL DISTURBANCE THAT WILL MOVE ACROSS THE
GULF EARLY NEXT WEEK STILL HAS THE POTENTIAL TO PRODUCE PRECIP
ACROSS THE SOUTHERN CWA ON TUESDAY AND WEDNESDAY. THIS SCENARIO
IS SUPPORTED BY BOTH THE GFS AND ECMWF. BY THURSDAY...MODELS START
TO DIVERGE. THE GFS NOW TAKES THE TROPICAL DISTURBANCE ON A MUCH
MORE NORTHERN TRACK AND RECURVES IT ACROSS NORTH TEXAS FRIDAY AND
SATURDAY. THE ECMWF HOLDS THE SUBTROPICAL RIDGE TO THE NORTH OF
THE TROPICAL SYSTEM AND SHUNTS IT WESTWARD INTO MEXICO. IF THE GFS
IS RIGHT...THE LATE WEEK TIME PERIODS WILL BE WET BUT SINCE THIS
IS A NEW WRINKLE I WILL STICK WITH CONTINUITY AND ADD NO POPS TO
THE FORECAST. IF THE ECMWF STARTS TO AGREE WITH THAT TRACK...THE
LATER FORECASTS WILL LIKELY BE ADDING POPS LATE NEXT WEEK. 84
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 94 74 93 72 94 / 50 20 10 5 5
WACO, TX 95 74 93 73 96 / 30 20 10 10 10
PARIS, TX 90 72 90 71 92 / 40 20 10 10 10
DENTON, TX 93 74 93 72 93 / 40 20 10 5 5
MCKINNEY, TX 92 73 92 72 94 / 50 20 10 10 10
DALLAS, TX 94 74 93 72 94 / 50 20 10 5 5
TERRELL, TX 93 73 92 71 93 / 50 20 10 10 10
CORSICANA, TX 92 74 92 72 94 / 30 20 20 10 10
TEMPLE, TX 92 75 91 74 93 / 30 10 10 5 10
MINERAL WELLS, TX 93 74 93 72 94 / 40 20 10 5 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
82/58
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1224 PM CDT FRI JUN 15 2012
.AVIATION...
CONCERNS...POTENTIAL FOR THUNDER THIS AFTERNOON AND MVFR CIGS
POSSIBLE EARLY SATURDAY MORNING.
A CHANCE FOR THUNDERSTORMS CONTINUES THIS AFTERNOON AT THE DFW
AIRPORTS BUT WILL NOT MENTION THUNDER IN THE KACT TAF AS THE BEST
CHANCES WILL BE NORTH AND EAST OF THE AIRPORT. SCATTERED
THUNDERSTORM ACTIVITY IS EXPECTED TO DEVELOP THROUGH THE AFTERNOON
AS A REMNANT DISTURBANCE FROM LAST NIGHT/S CONVECTION MOVES ALONG
THE RED RIVER. THINK THE BEST TIMING FOR STORMS TO AFFECT THE DFW
TERMINALS IS BETWEEN 20-00Z. SOME OF THE STORMS COULD BE STRONG OR
SEVERE WITH A THREAT FOR LIGHTNING...HAIL...AND GUSTY WINDS.
VFR CONDITIONS ARE EXPECTED TO PREVAIL FOR MUCH OF THE EVENING BUT
THERE IS SOME CONCERN THAT ADDITIONAL RAIN/STORMS MAY DEVELOP
OVERNIGHT. CONFIDENCE IS NOT OVERLY HIGH IN THIS SCENARIO...THUS
WILL NOT MENTION THUNDER OVERNIGHT AT THIS TIME. THERE IS ALSO THE
POTENTIAL FOR MVFR CIGS TO DEVELOP AGAIN TONIGHT. THE CONVECTION
THIS AFTERNOON COULD AFFECT WHERE THE CIGS DEVELOP BUT THE
ATMOSPHERE HAS AMPLE MOISTURE FOR MVFR STRATUS DEVELOPMENT. WITH A
HIGHER POTENTIAL AT KACT...WILL KEEP THE MVFR CIGS AT KACT TONIGHT
BUT ADJUST THE METROPLEX TAFS TO MENTION A SCT020 DECK EARLY
WEDNESDAY MORNING.
82/JLD
&&
.UPDATE...
ISOLATED SHOWERS AND THUNDERSTORMS CONTINUE LATE THIS MORNING
EAST OF A GAINESVILLE TO STEPHENVILLE LINE. A MCV NORTHWEST OF THE
METROPLEX WILL MOVE EAST THIS AFTERNOON...WITH THE DEEPEST
MOISTURE ACROSS THE EAST. THE BEST CHANCES OF SHOWERS AND
THUNDERSTORMS THIS AFTERNOON AND EVENING WILL BE OVER THE
NORTHERN AND EASTERN ZONES WHERE WE HAVE PLACED THE HIGHEST POPS
OF 30-40 PERCENT. THE STORMS THAT DEVELOP WILL HAVE THE
POTENTIAL TO BECOME SEVERE...PRODUCING LARGE HAIL...DAMAGING
WINDS...FREQUENT CLOUD TO GROUND LIGHTNING AND HEAVY RAIN.
58
&&
.PREV DISCUSSION... /ISSUED 330 AM CDT FRI JUN 15 2012/
MANY MODELS CONTINUE TO OVER-STABILIZE THE ATMOSPHERE...AND ONCE
AGAIN THE RESULT IS THAT THE ATMOSPHERE RETAINS ENOUGH
INSTABILITY TO SUPPORT CONVECTION. THE SHORT WAVE FEATURES
ASSOCIATED WITH THESE SYSTEMS ARE WEAK...AND IT MAY BE THAT THE
SMOOTHING SCHEMES USED IN MODEL INITIATION ARE DESTROYING THESE
FEATURES THAT ARE PRODUCING WEATHER.
FOR TODAY...THE TTU WRF AND 00Z GFS COMPLETELY MISSED THE ONGOING
CONVECTION. THE HRRR IS NOT AVAILABLE. THE RAP/RUC FAILED TO
ADVECT THE STORMS INTO OUR AREA. OUN WRF AND NCEP 4KM WRF BOTH
FORECAST THE NOCTURNAL CONVECTION TO CONTINUE INTO NORTH TEXAS.
THE NAM PRODUCED NO PRECIPITATION TODAY...BUT CROSS SECTION
ANALYSIS SHOWS INSTABILITY AND MOISTURE ABOVE THE MORNING
INVERSION AND SO IT DOES SUPPORT THE POTENTIAL FOR CONVECTION.
ANOTHER FACTOR IS THE MCV THAT IS CURRENTLY CENTERED JUST WEST OF
FREDERICK AND SHOULD TRACK ACROSS SOUTHERN OKLAHOMA. ANY FORCING
FOR LIFT GENERATED BY THIS FEATURE WILL LIKELY NOT BE RESOLVED IN
THIS MORNING/S MODELS. IT MAY BE THAT WEDNESDAY AFTERNOON/S MCV
THAT TRACKED SIMILARLY TO THIS ONE HAD AN INFLUENCE ON THE NORTH
TEXAS CONVECTION THAT PRODUCED THE LARGE HAIL. THUS I HAVE KEPT
POPS ACROSS THE ENTIRE CWA THIS MORNING AND THE EASTERN THIRD
THIS AFTERNOON. WITH DEW POINTS IN THE LOW TO MID 70S...IT WILL
NOT TAKE MUCH FORCING TO DESTABILIZE THIS ATMOSPHERE.
I CONTINUED THE LOW POPS IN THE SOUTHEAST FOR SATURDAY
AFTERNOON...THEN IT APPEARS THAT NORTH TEXAS WILL REMAIN DRY
THROUGH MONDAY. THE TROPICAL DISTURBANCE THAT WILL MOVE ACROSS THE
GULF EARLY NEXT WEEK STILL HAS THE POTENTIAL TO PRODUCE PRECIP
ACROSS THE SOUTHERN CWA ON TUESDAY AND WEDNESDAY. THIS SCENARIO
IS SUPPORTED BY BOTH THE GFS AND ECMWF. BY THURSDAY...MODELS START
TO DIVERGE. THE GFS NOW TAKES THE TROPICAL DISTURBANCE ON A MUCH
MORE NORTHERN TRACK AND RECURVES IT ACROSS NORTH TEXAS FRIDAY AND
SATURDAY. THE ECMWF HOLDS THE SUBTROPICAL RIDGE TO THE NORTH OF
THE TROPICAL SYSTEM AND SHUNTS IT WESTWARD INTO MEXICO. IF THE GFS
IS RIGHT...THE LATE WEEK TIME PERIODS WILL BE WET BUT SINCE THIS
IS A NEW WRINKLE I WILL STICK WITH CONTINUITY AND ADD NO POPS TO
THE FORECAST. IF THE ECMWF STARTS TO AGREE WITH THAT TRACK...THE
LATER FORECASTS WILL LIKELY BE ADDING POPS LATE NEXT WEEK. 84
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 94 74 93 72 94 / 50 20 10 5 5
WACO, TX 95 74 93 73 96 / 30 20 10 10 10
PARIS, TX 90 72 90 71 92 / 40 20 10 10 10
DENTON, TX 93 74 93 72 93 / 40 20 10 5 5
MCKINNEY, TX 92 73 92 72 94 / 50 20 10 10 10
DALLAS, TX 94 74 93 72 94 / 50 20 10 5 5
TERRELL, TX 93 73 92 71 93 / 50 20 10 10 10
CORSICANA, TX 92 74 92 72 94 / 30 20 20 10 10
TEMPLE, TX 92 75 91 74 93 / 30 10 10 5 10
MINERAL WELLS, TX 93 74 93 72 94 / 40 20 10 5 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
82/58
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
1125 AM CDT FRI JUN 15 2012
.UPDATE...
ISOLATED SHOWERS AND THUNDERSTORMS CONTINUE LATE THIS MORNING
EAST OF A GAINESVILLE TO STEPHENVILLE LINE. A MCV NORTHWEST OF THE
METROPLEX WILL MOVE EAST THIS AFTERNOON...WITH THE DEEPEST
MOISTURE ACROSS THE EAST. THE BEST CHANCES OF SHOWERS AND
THUNDERSTORMS THIS AFTERNOON AND EVENING WILL BE OVER THE
NORTHERN AND EASTERN ZONES WHERE WE HAVE PLACED THE HIGHEST POPS
OF 30-40 PERCENT. THE STORMS THAT DEVELOP WILL HAVE THE
POTENTIAL TO BECOME SEVERE...PRODUCING LARGE HAIL...DAMAGING
WINDS...FREQUENT CLOUD TO GROUND LIGHTNING AND HEAVY RAIN.
58
&&
.AVIATION UPDATE...
TODAY PRESENTS A CHALLENGING CONVECTIVE FORECAST FOR THE NORTH
TEXAS REGION. A REMNANT MCV FROM LAST NIGHT/S CONVECTION
CONTINUES TO SPIN TO THE NORTHWEST OF THE DFW METROPLEX TAF SITES.
WHILE THIS FEATURE SLOWLY MOVES EAST TODAY...SCATTERED SHOWERS AND
THUNDERSTORMS WILL CONTINUE TO DEVELOP THROUGHOUT THE DAY. MOST OF
THIS ACTIVITY WILL BE NORTH OF THE METROPLEX BUT SOME
THUNDERSTORMS ARE POSSIBLE NEAR THE TAF SITES. VISIBLE SATELLITE
IS ALREADY SHOWING ENHANCED CLOUDS STRETCHING FROM NEAR DFW TO THE
RED RIVER. GIVEN THE POTENTIAL FOR TODAY...WILL AMEND TO RETURN
VCSH TO THE DFW TAFS THROUGH 19Z AND THEN TREND TO VCTS FOR THE
AFTERNOON HOURS. IT IS POSSIBLE THAT ANY OF THESE STORMS COULD BE
SEVERE WITH A THREAT FOR HAIL AND DAMAGING WINDS.
AM STILL ASSESSING THE THREAT FOR THUNDER AT KACT TODAY AND WILL
ADDRESS THIS WITH THE 18Z TAF ISSUANCE BUT THE THREAT FOR THUNDER
AROUND WACO IS LOWER THAN IN THE METROPLEX.
82/JLD
.../PREVIOUS AVIATION DISCUSSION/...
FOR THE 12Z TAFS...SHORT TERM THUNDERSTORM TRENDS ARE THE PRIMARY
FORECAST CONCERN...FOLLOWED BY THUNDERSTORM CHANCES THROUGH THIS
EVENING AND THEN STRATUS POTENTIAL AFTER MIDNIGHT.
SHORT TERM TRENDS...THE PRIMARY LINE OF STORMS HAS MOVED EAST OF
ALL METROPLEX TAF SITES...HOWEVER A BROAD AREA OF LIGHT RAINFALL
REMAINS IN PLACE OVER MOST SITES WITH ISOLATED THUNDERSTORMS
REDEVELOPING OVER WESTERN TARRANT AND EASTERN WISE COUNTIES. THE
STRONGEST OF THESE NEW STORMS REMAINS IN WISE COUNTY...NORTHWEST
OF AREA TAF SITES...BUT THIS ACTIVITY HAS BEEN SLOWLY DEVELOPING
SOUTH OVER THE PAST 20 MINUTES. EXTENDED THE MENTION OF VCTS IN
THE TAFS THROUGH 13Z TO ACCOUNT FOR THE HIGH LIKELIHOOD OF A
THUNDERSTORM WITHIN 5 MILES OF A TAF SITE FOR THE NEXT HOUR. HELD
ON TO VCSH FOR AN HOUR THEREAFTER TO ACCOUNT FOR UNCERTAINTY
ASSOCIATED WITH NEW DEVELOPMENT WEST AND NORTHWEST OF METROPLEX
AREA TAF SITES. DO NOT EXPECT STORMS TO BECOME SEVERE THROUGH 15Z.
THUNDERSTORM CHANCES THROUGH THIS AFTERNOON...ASSUMING ONGOING
ACTIVITY CLEARS UP AT SOME POINT THIS MORNING...ATTENTION THEN
TURNS TO THE MCV CURRENTLY CENTERED OVER LAWTON...OK. SOME HIGH
RESOLUTION MODELS INDICATE THAT ONGOING ACTIVITY WILL CLEAR UP BY
14Z. THESE MODELS ALSO INDICATE THAT STRONG TO SEVERE STORMS WILL
REDEVELOP NEAR THE RED RIVER AROUND NOON DUE TO THE INFLUENCE OF
THE SOUTHERN OK MCV. AT THIS TIME THIS GUIDANCE KEEPS STRONG TO
SEVERE THUNDERSTORM ACTIVITY NORTH OF METROPLEX TAF
SITES...HOWEVER THIS IS A FEATURE WE WILL HAVE TO WATCH CLOSELY
THROUGHOUT THE DAY AS IT COULD BRING THUNDERSTORM ACTIVITY TOWARDS
THE METROPLEX BY THIS AFTERNOON. DO NOT HAVE ANY MENTION OF THIS
IN THE TAFS AT THIS TIME BECAUSE CONFIDENCE IS TOO LOW...THINKING
AROUND A 20 PERCENT CHANCE...THAT THIS SCENARIO WILL PAN OUT. IF
CONFIDENCE INCREASES LATER THIS MORNING THUNDERSTORMS MAY BE ADDED
TO THE TAFS FOR THIS AFTERNOON.
STRATUS...OPERATIONAL MODELS CONTINUE TO ADVERTISE A SIGNAL FOR
MVFR STRATUS EARLY TOMORROW MORNING. LEFT THIS IN THE TAFS AT THIS
TIME BUT RAISED CIGS A FEW HUNDRED FEET TO BRING ABOVE 2 KFT FOR
THE TIME BEING.
CAVANAUGH
82
&&
.PREV UPDATE...
.UPDATE...
UPPED POPS TO 50 PERCENT FOR THE MORNING ALONG AND AHEAD OF THE
CURRENT PRECIP. STORMS STILL WEAKENING...BUT SHOULD LAST PAST 7
AM. SLIGHT TWEAKS TO TEMPS/CLOUDS AS WELL. ALSO UPPED POPS TO
SLIGHT CHANCE NORTH OF INTERSTATE 20 AND WEST OF INTERSTATE 35 FOR
THIS AFTERNOON...MCV THAT WILL TRANSIT NEAR THAT AREA COULD STILL
PRODUCE CONVECTION AS INDICATED BY NORMAN WRF. 84
&&
.PREV DISCUSSION... /ISSUED 330 AM CDT FRI JUN 15 2012/
MANY MODELS CONTINUE TO OVER-STABILIZE THE ATMOSPHERE...AND ONCE
AGAIN THE RESULT IS THAT THE ATMOSPHERE RETAINS ENOUGH
INSTABILITY TO SUPPORT CONVECTION. THE SHORT WAVE FEATURES
ASSOCIATED WITH THESE SYSTEMS ARE WEAK...AND IT MAY BE THAT THE
SMOOTHING SCHEMES USED IN MODEL INITIATION ARE DESTROYING THESE
FEATURES THAT ARE PRODUCING WEATHER.
FOR TODAY...THE TTU WRF AND 00Z GFS COMPLETELY MISSED THE ONGOING
CONVECTION. THE HRRR IS NOT AVAILABLE. THE RAP/RUC FAILED TO
ADVECT THE STORMS INTO OUR AREA. OUN WRF AND NCEP 4KM WRF BOTH
FORECAST THE NOCTURNAL CONVECTION TO CONTINUE INTO NORTH TEXAS.
THE NAM PRODUCED NO PRECIPITATION TODAY...BUT CROSS SECTION
ANALYSIS SHOWS INSTABILITY AND MOISTURE ABOVE THE MORNING
INVERSION AND SO IT DOES SUPPORT THE POTENTIAL FOR CONVECTION.
ANOTHER FACTOR IS THE MCV THAT IS CURRENTLY CENTERED JUST WEST OF
FREDERICK AND SHOULD TRACK ACROSS SOUTHERN OKLAHOMA. ANY FORCING
FOR LIFT GENERATED BY THIS FEATURE WILL LIKELY NOT BE RESOLVED IN
THIS MORNING/S MODELS. IT MAY BE THAT WEDNESDAY AFTERNOON/S MCV
THAT TRACKED SIMILARLY TO THIS ONE HAD AN INFLUENCE ON THE NORTH
TEXAS CONVECTION THAT PRODUCED THE LARGE HAIL. THUS I HAVE KEPT
POPS ACROSS THE ENTIRE CWA THIS MORNING AND THE EASTERN THIRD
THIS AFTERNOON. WITH DEW POINTS IN THE LOW TO MID 70S...IT WILL
NOT TAKE MUCH FORCING TO DESTABILIZE THIS ATMOSPHERE.
I CONTINUED THE LOW POPS IN THE SOUTHEAST FOR SATURDAY
AFTERNOON...THEN IT APPEARS THAT NORTH TEXAS WILL REMAIN DRY
THROUGH MONDAY. THE TROPICAL DISTURBANCE THAT WILL MOVE ACROSS THE
GULF EARLY NEXT WEEK STILL HAS THE POTENTIAL TO PRODUCE PRECIP
ACROSS THE SOUTHERN CWA ON TUESDAY AND WEDNESDAY. THIS SCENARIO
IS SUPPORTED BY BOTH THE GFS AND ECMWF. BY THURSDAY...MODELS START
TO DIVERGE. THE GFS NOW TAKES THE TROPICAL DISTURBANCE ON A MUCH
MORE NORTHERN TRACK AND RECURVES IT ACROSS NORTH TEXAS FRIDAY AND
SATURDAY. THE ECMWF HOLDS THE SUBTROPICAL RIDGE TO THE NORTH OF
THE TROPICAL SYSTEM AND SHUNTS IT WESTWARD INTO MEXICO. IF THE GFS
IS RIGHT...THE LATE WEEK TIME PERIODS WILL BE WET BUT SINCE THIS
IS A NEW WRINKLE I WILL STICK WITH CONTINUITY AND ADD NO POPS TO
THE FORECAST. IF THE ECMWF STARTS TO AGREE WITH THAT TRACK...THE
LATER FORECASTS WILL LIKELY BE ADDING POPS LATE NEXT WEEK. 84
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 94 74 93 72 94 / 50 20 10 5 5
WACO, TX 95 74 93 73 96 / 30 20 10 10 10
PARIS, TX 90 72 90 71 92 / 40 20 10 10 10
DENTON, TX 93 74 93 72 93 / 40 20 10 5 5
MCKINNEY, TX 92 73 92 72 94 / 50 20 10 10 10
DALLAS, TX 94 74 93 72 94 / 50 20 10 5 5
TERRELL, TX 93 73 92 71 93 / 50 20 10 10 10
CORSICANA, TX 92 74 92 72 94 / 30 20 20 10 10
TEMPLE, TX 92 75 91 74 93 / 30 10 10 5 10
MINERAL WELLS, TX 93 74 93 72 94 / 40 20 10 5 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
82/58
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1053 AM CDT FRI JUN 15 2012
.AVIATION UPDATE...
TODAY PRESENTS A CHALLENGING CONVECTIVE FORECAST FOR THE NORTH
TEXAS REGION. A REMNANT MCV FROM LAST NIGHT/S CONVECTION
CONTINUES TO SPIN TO THE NORTHWEST OF THE DFW METROPLEX TAF SITES.
WHILE THIS FEATURE SLOWLY MOVES EAST TODAY...SCATTERED SHOWERS AND
THUNDERSTORMS WILL CONTINUE TO DEVELOP THROUGHOUT THE DAY. MOST OF
THIS ACTIVITY WILL BE NORTH OF THE METROPLEX BUT SOME
THUNDERSTORMS ARE POSSIBLE NEAR THE TAF SITES. VISIBLE SATELLITE
IS ALREADY SHOWING ENHANCED CLOUDS STRETCHING FROM NEAR DFW TO THE
RED RIVER. GIVEN THE POTENTIAL FOR TODAY...WILL AMEND TO RETURN
VCSH TO THE DFW TAFS THROUGH 19Z AND THEN TREND TO VCTS FOR THE
AFTERNOON HOURS. IT IS POSSIBLE THAT ANY OF THESE STORMS COULD BE
SEVERE WITH A THREAT FOR HAIL AND DAMAGING WINDS.
AM STILL ASSESSING THE THREAT FOR THUNDER AT KACT TODAY AND WILL
ADDRESS THIS WITH THE 18Z TAF ISSUANCE BUT THE THREAT FOR THUNDER
AROUND WACO IS LOWER THAN IN THE METROPLEX.
82/JLD
.../PREVIOUS AVIATION DISCUSSION/...
FOR THE 12Z TAFS...SHORT TERM THUNDERSTORM TRENDS ARE THE PRIMARY
FORECAST CONCERN...FOLLOWED BY THUNDERSTORM CHANCES THROUGH THIS
EVENING AND THEN STRATUS POTENTIAL AFTER MIDNIGHT.
SHORT TERM TRENDS...THE PRIMARY LINE OF STORMS HAS MOVED EAST OF
ALL METROPLEX TAF SITES...HOWEVER A BROAD AREA OF LIGHT RAINFALL
REMAINS IN PLACE OVER MOST SITES WITH ISOLATED THUNDERSTORMS
REDEVELOPING OVER WESTERN TARRANT AND EASTERN WISE COUNTIES. THE
STRONGEST OF THESE NEW STORMS REMAINS IN WISE COUNTY...NORTHWEST
OF AREA TAF SITES...BUT THIS ACTIVITY HAS BEEN SLOWLY DEVELOPING
SOUTH OVER THE PAST 20 MINUTES. EXTENDED THE MENTION OF VCTS IN
THE TAFS THROUGH 13Z TO ACCOUNT FOR THE HIGH LIKELIHOOD OF A
THUNDERSTORM WITHIN 5 MILES OF A TAF SITE FOR THE NEXT HOUR. HELD
ON TO VCSH FOR AN HOUR THEREAFTER TO ACCOUNT FOR UNCERTAINTY
ASSOCIATED WITH NEW DEVELOPMENT WEST AND NORTHWEST OF METROPLEX
AREA TAF SITES. DO NOT EXPECT STORMS TO BECOME SEVERE THROUGH 15Z.
THUNDERSTORM CHANCES THROUGH THIS AFTERNOON...ASSUMING ONGOING
ACTIVITY CLEARS UP AT SOME POINT THIS MORNING...ATTENTION THEN
TURNS TO THE MCV CURRENTLY CENTERED OVER LAWTON...OK. SOME HIGH
RESOLUTION MODELS INDICATE THAT ONGOING ACTIVITY WILL CLEAR UP BY
14Z. THESE MODELS ALSO INDICATE THAT STRONG TO SEVERE STORMS WILL
REDEVELOP NEAR THE RED RIVER AROUND NOON DUE TO THE INFLUENCE OF
THE SOUTHERN OK MCV. AT THIS TIME THIS GUIDANCE KEEPS STRONG TO
SEVERE THUNDERSTORM ACTIVITY NORTH OF METROPLEX TAF
SITES...HOWEVER THIS IS A FEATURE WE WILL HAVE TO WATCH CLOSELY
THROUGHOUT THE DAY AS IT COULD BRING THUNDERSTORM ACTIVITY TOWARDS
THE METROPLEX BY THIS AFTERNOON. DO NOT HAVE ANY MENTION OF THIS
IN THE TAFS AT THIS TIME BECAUSE CONFIDENCE IS TOO LOW...THINKING
AROUND A 20 PERCENT CHANCE...THAT THIS SCENARIO WILL PAN OUT. IF
CONFIDENCE INCREASES LATER THIS MORNING THUNDERSTORMS MAY BE ADDED
TO THE TAFS FOR THIS AFTERNOON.
STRATUS...OPERATIONAL MODELS CONTINUE TO ADVERTISE A SIGNAL FOR
MVFR STRATUS EARLY TOMORROW MORNING. LEFT THIS IN THE TAFS AT THIS
TIME BUT RAISED CIGS A FEW HUNDRED FEET TO BRING ABOVE 2 KFT FOR
THE TIME BEING.
CAVANAUGH
82
&&
.UPDATE...
UPPED POPS TO 50 PERCENT FOR THE MORNING ALONG AND AHEAD OF THE
CURRENT PRECIP. STORMS STILL WEAKENING...BUT SHOULD LAST PAST 7
AM. SLIGHT TWEAKS TO TEMPS/CLOUDS AS WELL. ALSO UPPED POPS TO
SLIGHT CHANCE NORTH OF INTERSTATE 20 AND WEST OF INTERSTATE 35 FOR
THIS AFTERNOON...MCV THAT WILL TRANSIT NEAR THAT AREA COULD STILL
PRODUCE CONVECTION AS INDICATED BY NORMAN WRF. 84
&&
.PREV DISCUSSION... /ISSUED 330 AM CDT FRI JUN 15 2012/
MANY MODELS CONTINUE TO OVER-STABILIZE THE ATMOSPHERE...AND ONCE
AGAIN THE RESULT IS THAT THE ATMOSPHERE RETAINS ENOUGH
INSTABILITY TO SUPPORT CONVECTION. THE SHORT WAVE FEATURES
ASSOCIATED WITH THESE SYSTEMS ARE WEAK...AND IT MAY BE THAT THE
SMOOTHING SCHEMES USED IN MODEL INITIATION ARE DESTROYING THESE
FEATURES THAT ARE PRODUCING WEATHER.
FOR TODAY...THE TTU WRF AND 00Z GFS COMPLETELY MISSED THE ONGOING
CONVECTION. THE HRRR IS NOT AVAILABLE. THE RAP/RUC FAILED TO
ADVECT THE STORMS INTO OUR AREA. OUN WRF AND NCEP 4KM WRF BOTH
FORECAST THE NOCTURNAL CONVECTION TO CONTINUE INTO NORTH TEXAS.
THE NAM PRODUCED NO PRECIPITATION TODAY...BUT CROSS SECTION
ANALYSIS SHOWS INSTABILITY AND MOISTURE ABOVE THE MORNING
INVERSION AND SO IT DOES SUPPORT THE POTENTIAL FOR CONVECTION.
ANOTHER FACTOR IS THE MCV THAT IS CURRENTLY CENTERED JUST WEST OF
FREDERICK AND SHOULD TRACK ACROSS SOUTHERN OKLAHOMA. ANY FORCING
FOR LIFT GENERATED BY THIS FEATURE WILL LIKELY NOT BE RESOLVED IN
THIS MORNING/S MODELS. IT MAY BE THAT WEDNESDAY AFTERNOON/S MCV
THAT TRACKED SIMILARLY TO THIS ONE HAD AN INFLUENCE ON THE NORTH
TEXAS CONVECTION THAT PRODUCED THE LARGE HAIL. THUS I HAVE KEPT
POPS ACROSS THE ENTIRE CWA THIS MORNING AND THE EASTERN THIRD
THIS AFTERNOON. WITH DEW POINTS IN THE LOW TO MID 70S...IT WILL
NOT TAKE MUCH FORCING TO DESTABILIZE THIS ATMOSPHERE.
I CONTINUED THE LOW POPS IN THE SOUTHEAST FOR SATURDAY
AFTERNOON...THEN IT APPEARS THAT NORTH TEXAS WILL REMAIN DRY
THROUGH MONDAY. THE TROPICAL DISTURBANCE THAT WILL MOVE ACROSS THE
GULF EARLY NEXT WEEK STILL HAS THE POTENTIAL TO PRODUCE PRECIP
ACROSS THE SOUTHERN CWA ON TUESDAY AND WEDNESDAY. THIS SCENARIO
IS SUPPORTED BY BOTH THE GFS AND ECMWF. BY THURSDAY...MODELS START
TO DIVERGE. THE GFS NOW TAKES THE TROPICAL DISTURBANCE ON A MUCH
MORE NORTHERN TRACK AND RECURVES IT ACROSS NORTH TEXAS FRIDAY AND
SATURDAY. THE ECMWF HOLDS THE SUBTROPICAL RIDGE TO THE NORTH OF
THE TROPICAL SYSTEM AND SHUNTS IT WESTWARD INTO MEXICO. IF THE GFS
IS RIGHT...THE LATE WEEK TIME PERIODS WILL BE WET BUT SINCE THIS
IS A NEW WRINKLE I WILL STICK WITH CONTINUITY AND ADD NO POPS TO
THE FORECAST. IF THE ECMWF STARTS TO AGREE WITH THAT TRACK...THE
LATER FORECASTS WILL LIKELY BE ADDING POPS LATE NEXT WEEK. 84
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 94 74 93 72 94 / 50 20 10 5 5
WACO, TX 95 74 93 73 96 / 30 20 10 10 10
PARIS, TX 90 72 90 71 92 / 40 20 10 10 10
DENTON, TX 93 74 93 72 93 / 40 20 10 5 5
MCKINNEY, TX 92 73 92 72 94 / 50 20 10 10 10
DALLAS, TX 94 74 93 72 94 / 50 20 10 5 5
TERRELL, TX 93 73 92 71 93 / 50 20 10 10 10
CORSICANA, TX 92 74 92 72 94 / 30 20 20 10 10
TEMPLE, TX 92 75 91 74 93 / 30 10 10 5 10
MINERAL WELLS, TX 93 74 93 72 94 / 40 20 10 5 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
82/58
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
656 AM CDT FRI JUN 15 2012
.AVIATION...
FOR THE 12Z TAFS...SHORT TERM THUNDERSTORM TRENDS ARE THE PRIMARY
FORECAST CONCERN...FOLLOWED BY THUNDERSTORM CHANCES THROUGH THIS
EVENING AND THEN STRATUS POTENTIAL AFTER MIDNIGHT.
SHORT TERM TRENDS...THE PRIMARY LINE OF STORMS HAS MOVED EAST OF
ALL METROPLEX TAF SITES...HOWEVER A BROAD AREA OF LIGHT RAINFALL
REMAINS IN PLACE OVER MOST SITES WITH ISOLATED THUNDERSTORMS
REDEVELOPING OVER WESTERN TARRANT AND EASTERN WISE COUNTIES. THE
STRONGEST OF THESE NEW STORMS REMAINS IN WISE COUNTY...NORTHWEST
OF AREA TAF SITES...BUT THIS ACTIVITY HAS BEEN SLOWLY DEVELOPING
SOUTH OVER THE PAST 20 MINUTES. EXTENDED THE MENTION OF VCTS IN
THE TAFS THROUGH 13Z TO ACCOUNT FOR THE HIGH LIKELIHOOD OF A
THUNDERSTORM WITHIN 5 MILES OF A TAF SITE FOR THE NEXT HOUR. HELD
ON TO VCSH FOR AN HOUR THEREAFTER TO ACCOUNT FOR UNCERTAINTY
ASSOCIATED WITH NEW DEVELOPMENT WEST AND NORTHWEST OF METROPLEX
AREA TAF SITES. DO NOT EXPECT STORMS TO BECOME SEVERE THROUGH 15Z.
THUNDERSTORM CHANCES THROUGH THIS AFTERNOON...ASSUMING ONGOING
ACTIVITY CLEARS UP AT SOME POINT THIS MORNING...ATTENTION THEN
TURNS TO THE MCV CURRENTLY CENTERED OVER LAWTON...OK. SOME HIGH
RESOLUTION MODELS INDICATE THAT ONGOING ACTIVITY WILL CLEAR UP BY
14Z. THESE MODELS ALSO INDICATE THAT STRONG TO SEVERE STORMS WILL
REDEVELOP NEAR THE RED RIVER AROUND NOON DUE TO THE INFLUENCE OF
THE SOUTHERN OK MCV. AT THIS TIME THIS GUIDANCE KEEPS STRONG TO
SEVERE THUNDERSTORM ACTIVITY NORTH OF METROPLEX TAF
SITES...HOWEVER THIS IS A FEATURE WE WILL HAVE TO WATCH CLOSELY
THROUGHOUT THE DAY AS IT COULD BRING THUNDERSTORM ACTIVITY TOWARDS
THE METROPLEX BY THIS AFTERNOON. DO NOT HAVE ANY MENTION OF THIS
IN THE TAFS AT THIS TIME BECAUSE CONFIDENCE IS TOO LOW...THINKING
AROUND A 20 PERCENT CHANCE...THAT THIS SCENARIO WILL PAN OUT. IF
CONFIDENCE INCREASES LATER THIS MORNING THUNDERSTORMS MAY BE ADDED
TO THE TAFS FOR THIS AFTERNOON.
STRATUS...OPERATIONAL MODELS CONTINUE TO ADVERTISE A SIGNAL FOR
MVFR STRATUS EARLY TOMORROW MORNING. LEFT THIS IN THE TAFS AT THIS
TIME BUT RAISED CIGS A FEW HUNDRED FEET TO BRING ABOVE 2 KFT FOR
THE TIME BEING.
CAVANAUGH
&&
.UPDATE...
UPPED POPS TO 50 PERCENT FOR THE MORNING ALONG AND AHEAD OF THE
CURRENT PRECIP. STORMS STILL WEAKENING...BUT SHOULD LAST PAST 7
AM. SLIGHT TWEAKS TO TEMPS/CLOUDS AS WELL. ALSO UPPED POPS TO
SLIGHT CHANCE NORTH OF INTERSTATE 20 AND WEST OF INTERSTATE 35 FOR
THIS AFTERNOON...MCV THAT WILL TRANSIT NEAR THAT AREA COULD STILL
PRODUCE CONVECTION AS INDICATED BY NORMAN WRF. 84
&&
.PREV DISCUSSION... /ISSUED 330 AM CDT FRI JUN 15 2012/
MANY MODELS CONTINUE TO OVER-STABILIZE THE ATMOSPHERE...AND ONCE
AGAIN THE RESULT IS THAT THE ATMOSPHERE RETAINS ENOUGH
INSTABILITY TO SUPPORT CONVECTION. THE SHORT WAVE FEATURES
ASSOCIATED WITH THESE SYSTEMS ARE WEAK...AND IT MAY BE THAT THE
SMOOTHING SCHEMES USED IN MODEL INITIATION ARE DESTROYING THESE
FEATURES THAT ARE PRODUCING WEATHER.
FOR TODAY...THE TTU WRF AND 00Z GFS COMPLETELY MISSED THE ONGOING
CONVECTION. THE HRRR IS NOT AVAILABLE. THE RAP/RUC FAILED TO
ADVECT THE STORMS INTO OUR AREA. OUN WRF AND NCEP 4KM WRF BOTH
FORECAST THE NOCTURNAL CONVECTION TO CONTINUE INTO NORTH TEXAS.
THE NAM PRODUCED NO PRECIPITATION TODAY...BUT CROSS SECTION
ANALYSIS SHOWS INSTABILITY AND MOISTURE ABOVE THE MORNING
INVERSION AND SO IT DOES SUPPORT THE POTENTIAL FOR CONVECTION.
ANOTHER FACTOR IS THE MCV THAT IS CURRENTLY CENTERED JUST WEST OF
FREDERICK AND SHOULD TRACK ACROSS SOUTHERN OKLAHOMA. ANY FORCING
FOR LIFT GENERATED BY THIS FEATURE WILL LIKELY NOT BE RESOLVED IN
THIS MORNING/S MODELS. IT MAY BE THAT WEDNESDAY AFTERNOON/S MCV
THAT TRACKED SIMILARLY TO THIS ONE HAD AN INFLUENCE ON THE NORTH
TEXAS CONVECTION THAT PRODUCED THE LARGE HAIL. THUS I HAVE KEPT
POPS ACROSS THE ENTIRE CWA THIS MORNING AND THE EASTERN THIRD
THIS AFTERNOON. WITH DEW POINTS IN THE LOW TO MID 70S...IT WILL
NOT TAKE MUCH FORCING TO DESTABILIZE THIS ATMOSPHERE.
I CONTINUED THE LOW POPS IN THE SOUTHEAST FOR SATURDAY
AFTERNOON...THEN IT APPEARS THAT NORTH TEXAS WILL REMAIN DRY
THROUGH MONDAY. THE TROPICAL DISTURBANCE THAT WILL MOVE ACROSS THE
GULF EARLY NEXT WEEK STILL HAS THE POTENTIAL TO PRODUCE PRECIP
ACROSS THE SOUTHERN CWA ON TUESDAY AND WEDNESDAY. THIS SCENARIO
IS SUPPORTED BY BOTH THE GFS AND ECMWF. BY THURSDAY...MODELS START
TO DIVERGE. THE GFS NOW TAKES THE TROPICAL DISTURBANCE ON A MUCH
MORE NORTHERN TRACK AND RECURVES IT ACROSS NORTH TEXAS FRIDAY AND
SATURDAY. THE ECMWF HOLDS THE SUBTROPICAL RIDGE TO THE NORTH OF
THE TROPICAL SYSTEM AND SHUNTS IT WESTWARD INTO MEXICO. IF THE GFS
IS RIGHT...THE LATE WEEK TIME PERIODS WILL BE WET BUT SINCE THIS
IS A NEW WRINKLE I WILL STICK WITH CONTINUITY AND ADD NO POPS TO
THE FORECAST. IF THE ECMWF STARTS TO AGREE WITH THAT TRACK...THE
LATER FORECASTS WILL LIKELY BE ADDING POPS LATE NEXT WEEK. 84
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 94 74 93 72 94 / 50 10 10 5 5
WACO, TX 95 74 93 73 96 / 20 10 10 10 10
PARIS, TX 90 72 90 71 92 / 20 10 10 10 10
DENTON, TX 93 74 93 72 93 / 40 10 10 5 5
MCKINNEY, TX 92 73 92 72 94 / 50 10 10 10 10
DALLAS, TX 94 74 93 72 94 / 50 10 10 5 5
TERRELL, TX 93 73 92 71 93 / 50 10 10 10 10
CORSICANA, TX 92 74 92 72 94 / 20 10 20 10 10
TEMPLE, TX 92 75 91 74 93 / 20 10 10 5 10
MINERAL WELLS, TX 93 74 93 72 94 / 30 10 10 5 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
552 AM CDT FRI JUN 15 2012
.UPDATE...
UPPED POPS TO 50 PERCENT FOR THE MORNING ALONG AND AHEAD OF THE
CURRENT PRECIP. STORMS STILL WEAKENING...BUT SHOULD LAST PAST 7
AM. SLIGHT TWEAKS TO TEMPS/CLOUDS AS WELL. ALSO UPPED POPS TO
SLIGHT CHANCE NORTH OF INTERSTATE 20 AND WEST OF INTERSTATE 35 FOR
THIS AFTERNOON...MCV THAT WILL TRANSIT NEAR THAT AREA COULD STILL
PRODUCE CONVECTION AS INDICATED BY NORMAN WRF. 84
&&
.AVIATION...
08Z AMENDMENTS OF 06Z TAFS...A LINE OF SHOWERS AND THUNDERSTORMS HAS
ORGANIZED NORTHWEST OF METROPLEX TAF SITES AND CONTINUES TO HOLD
TOGETHER WHILE MOVING SOUTHEAST AS OF 08Z. THIS LINE OF SHOWERS AND
STORMS WAS MOVING SOUTHEAST AT APPROXIMATELY 20 KTS. USED THIS
SPEED TO AMEND THE TAFS FOR THE WIND SHIFT LINE AND VICINITY THUNDER
FOR NOW...AND WILL UPDATE THE TIMING AGAIN WITH SCHEDULED 09Z
AMENDMENTS.
ASSUMING PRECIPITATION MAINTAINS ITS CURRENT COVERAGE AS IT GETS
CLOSER TO THE METROPLEX...WILL INCLUDE PRECIPITATION WITH MVFR VSBYS
IN ADDITION TO THE VCTS. CONFIDENCE IS HIGH IN A WIND SHIFT
AFFECTING ALL METROPLEX TAF SITES FROM 0930Z TO 1030Z. AT THIS TIME
ALL OF THIS ACTIVITY APPEARS TO BE ELEVATED OVER A STABLE COLD
LAYER/REMNANTS OF EARLIER THUNDERSTORM ACTIVITY. THEREFORE THIS
ACTIVITY IS NOT EXPECTED TO BECOME SEVERE AS IT MOVES OVER METROPLEX
AREA TAF SITES. WILL CONTINUE TO MONITOR RADAR TRENDS AND WILL
UPDATE THE AVIATION DISCUSSION IF ANY MAJOR CHANGE IN THE FORECAST
IS NECESSARY.
CAVANAUGH
&&
.PREV UPDATE...
.UPDATE...
UPPED POPS TO 50 PERCENT FOR THE MORNING ALONG AND AHEAD OF THE
CURRENT PRECIP. STORMS STILL WEAKENING...BUT SHOULD LAST PAST 7
AM. SLIGHT TWEAKS TO TEMPS/CLOUDS AS WELL. 84
&&
.PREV DISCUSSION... /ISSUED 330 AM CDT FRI JUN 15 2012/
MANY MODELS CONTINUE TO OVER-STABILIZE THE ATMOSPHERE...AND ONCE
AGAIN THE RESULT IS THAT THE ATMOSPHERE RETAINS ENOUGH
INSTABILITY TO SUPPORT CONVECTION. THE SHORT WAVE FEATURES
ASSOCIATED WITH THESE SYSTEMS ARE WEAK...AND IT MAY BE THAT THE
SMOOTHING SCHEMES USED IN MODEL INITIATION ARE DESTROYING THESE
FEATURES THAT ARE PRODUCING WEATHER.
FOR TODAY...THE TTU WRF AND 00Z GFS COMPLETELY MISSED THE ONGOING
CONVECTION. THE HRRR IS NOT AVAILABLE. THE RAP/RUC FAILED TO
ADVECT THE STORMS INTO OUR AREA. OUN WRF AND NCEP 4KM WRF BOTH
FORECAST THE NOCTURNAL CONVECTION TO CONTINUE INTO NORTH TEXAS.
THE NAM PRODUCED NO PRECIPITATION TODAY...BUT CROSS SECTION
ANALYSIS SHOWS INSTABILITY AND MOISTURE ABOVE THE MORNING
INVERSION AND SO IT DOES SUPPORT THE POTENTIAL FOR CONVECTION.
ANOTHER FACTOR IS THE MCV THAT IS CURRENTLY CENTERED JUST WEST OF
FREDERICK AND SHOULD TRACK ACROSS SOUTHERN OKLAHOMA. ANY FORCING
FOR LIFT GENERATED BY THIS FEATURE WILL LIKELY NOT BE RESOLVED IN
THIS MORNING/S MODELS. IT MAY BE THAT WEDNESDAY AFTERNOON/S MCV
THAT TRACKED SIMILARLY TO THIS ONE HAD AN INFLUENCE ON THE NORTH
TEXAS CONVECTION THAT PRODUCED THE LARGE HAIL. THUS I HAVE KEPT
POPS ACROSS THE ENTIRE CWA THIS MORNING AND THE EASTERN THIRD
THIS AFTERNOON. WITH DEW POINTS IN THE LOW TO MID 70S...IT WILL
NOT TAKE MUCH FORCING TO DESTABILIZE THIS ATMOSPHERE.
I CONTINUED THE LOW POPS IN THE SOUTHEAST FOR SATURDAY
AFTERNOON...THEN IT APPEARS THAT NORTH TEXAS WILL REMAIN DRY
THROUGH MONDAY. THE TROPICAL DISTURBANCE THAT WILL MOVE ACROSS THE
GULF EARLY NEXT WEEK STILL HAS THE POTENTIAL TO PRODUCE PRECIP
ACROSS THE SOUTHERN CWA ON TUESDAY AND WEDNESDAY. THIS SCENARIO
IS SUPPORTED BY BOTH THE GFS AND ECMWF. BY THURSDAY...MODELS START
TO DIVERGE. THE GFS NOW TAKES THE TROPICAL DISTURBANCE ON A MUCH
MORE NORTHERN TRACK AND RECURVES IT ACROSS NORTH TEXAS FRIDAY AND
SATURDAY. THE ECMWF HOLDS THE SUBTROPICAL RIDGE TO THE NORTH OF
THE TROPICAL SYSTEM AND SHUNTS IT WESTWARD INTO MEXICO. IF THE GFS
IS RIGHT...THE LATE WEEK TIME PERIODS WILL BE WET BUT SINCE THIS
IS A NEW WRINKLE I WILL STICK WITH CONTINUITY AND ADD NO POPS TO
THE FORECAST. IF THE ECMWF STARTS TO AGREE WITH THAT TRACK...THE
LATER FORECASTS WILL LIKELY BE ADDING POPS LATE NEXT WEEK. 84
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 94 74 93 72 94 / 50 10 10 5 5
WACO, TX 95 74 93 73 96 / 20 10 10 10 10
PARIS, TX 90 72 90 71 92 / 20 10 10 10 10
DENTON, TX 93 74 93 72 93 / 40 10 10 5 5
MCKINNEY, TX 92 73 92 72 94 / 50 10 10 10 10
DALLAS, TX 94 74 93 72 94 / 50 10 10 5 5
TERRELL, TX 93 73 92 71 93 / 50 10 10 10 10
CORSICANA, TX 92 74 92 72 94 / 20 10 20 10 10
TEMPLE, TX 92 75 91 74 93 / 20 10 10 5 10
MINERAL WELLS, TX 93 74 93 72 94 / 30 10 10 5 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
/
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
546 AM CDT FRI JUN 15 2012
.UPDATE...
UPPED POPS TO 50 PERCENT FOR THE MORNING ALONG AND AHEAD OF THE
CURRENT PRECIP. STORMS STILL WEAKENING...BUT SHOULD LAST PAST 7
AM. SLIGHT TWEAKS TO TEMPS/CLOUDS AS WELL. 84
&&
.AVIATION...
08Z AMENDMENTS OF 06Z TAFS...A LINE OF SHOWERS AND THUNDERSTORMS HAS
ORGANIZED NORTHWEST OF METROPLEX TAF SITES AND CONTINUES TO HOLD
TOGETHER WHILE MOVING SOUTHEAST AS OF 08Z. THIS LINE OF SHOWERS AND
STORMS WAS MOVING SOUTHEAST AT APPROXIMATELY 20 KTS. USED THIS
SPEED TO AMEND THE TAFS FOR THE WIND SHIFT LINE AND VICINITY THUNDER
FOR NOW...AND WILL UPDATE THE TIMING AGAIN WITH SCHEDULED 09Z
AMENDMENTS.
ASSUMING PRECIPITATION MAINTAINS ITS CURRENT COVERAGE AS IT GETS
CLOSER TO THE METROPLEX...WILL INCLUDE PRECIPITATION WITH MVFR VSBYS
IN ADDITION TO THE VCTS. CONFIDENCE IS HIGH IN A WIND SHIFT
AFFECTING ALL METROPLEX TAF SITES FROM 0930Z TO 1030Z. AT THIS TIME
ALL OF THIS ACTIVITY APPEARS TO BE ELEVATED OVER A STABLE COLD
LAYER/REMNANTS OF EARLIER THUNDERSTORM ACTIVITY. THEREFORE THIS
ACTIVITY IS NOT EXPECTED TO BECOME SEVERE AS IT MOVES OVER METROPLEX
AREA TAF SITES. WILL CONTINUE TO MONITOR RADAR TRENDS AND WILL
UPDATE THE AVIATION DISCUSSION IF ANY MAJOR CHANGE IN THE FORECAST
IS NECESSARY.
CAVANAUGH
&&
.PREV DISCUSSION... /ISSUED 330 AM CDT FRI JUN 15 2012/
MANY MODELS CONTINUE TO OVER-STABILIZE THE ATMOSPHERE...AND ONCE
AGAIN THE RESULT IS THAT THE ATMOSPHERE RETAINS ENOUGH
INSTABILITY TO SUPPORT CONVECTION. THE SHORT WAVE FEATURES
ASSOCIATED WITH THESE SYSTEMS ARE WEAK...AND IT MAY BE THAT THE
SMOOTHING SCHEMES USED IN MODEL INITIATION ARE DESTROYING THESE
FEATURES THAT ARE PRODUCING WEATHER.
FOR TODAY...THE TTU WRF AND 00Z GFS COMPLETELY MISSED THE ONGOING
CONVECTION. THE HRRR IS NOT AVAILABLE. THE RAP/RUC FAILED TO
ADVECT THE STORMS INTO OUR AREA. OUN WRF AND NCEP 4KM WRF BOTH
FORECAST THE NOCTURNAL CONVECTION TO CONTINUE INTO NORTH TEXAS.
THE NAM PRODUCED NO PRECIPITATION TODAY...BUT CROSS SECTION
ANALYSIS SHOWS INSTABILITY AND MOISTURE ABOVE THE MORNING
INVERSION AND SO IT DOES SUPPORT THE POTENTIAL FOR CONVECTION.
ANOTHER FACTOR IS THE MCV THAT IS CURRENTLY CENTERED JUST WEST OF
FREDERICK AND SHOULD TRACK ACROSS SOUTHERN OKLAHOMA. ANY FORCING
FOR LIFT GENERATED BY THIS FEATURE WILL LIKELY NOT BE RESOLVED IN
THIS MORNING/S MODELS. IT MAY BE THAT WEDNESDAY AFTERNOON/S MCV
THAT TRACKED SIMILARLY TO THIS ONE HAD AN INFLUENCE ON THE NORTH
TEXAS CONVECTION THAT PRODUCED THE LARGE HAIL. THUS I HAVE KEPT
POPS ACROSS THE ENTIRE CWA THIS MORNING AND THE EASTERN THIRD
THIS AFTERNOON. WITH DEW POINTS IN THE LOW TO MID 70S...IT WILL
NOT TAKE MUCH FORCING TO DESTABILIZE THIS ATMOSPHERE.
I CONTINUED THE LOW POPS IN THE SOUTHEAST FOR SATURDAY
AFTERNOON...THEN IT APPEARS THAT NORTH TEXAS WILL REMAIN DRY
THROUGH MONDAY. THE TROPICAL DISTURBANCE THAT WILL MOVE ACROSS THE
GULF EARLY NEXT WEEK STILL HAS THE POTENTIAL TO PRODUCE PRECIP
ACROSS THE SOUTHERN CWA ON TUESDAY AND WEDNESDAY. THIS SCENARIO
IS SUPPORTED BY BOTH THE GFS AND ECMWF. BY THURSDAY...MODELS START
TO DIVERGE. THE GFS NOW TAKES THE TROPICAL DISTURBANCE ON A MUCH
MORE NORTHERN TRACK AND RECURVES IT ACROSS NORTH TEXAS FRIDAY AND
SATURDAY. THE ECMWF HOLDS THE SUBTROPICAL RIDGE TO THE NORTH OF
THE TROPICAL SYSTEM AND SHUNTS IT WESTWARD INTO MEXICO. IF THE GFS
IS RIGHT...THE LATE WEEK TIME PERIODS WILL BE WET BUT SINCE THIS
IS A NEW WRINKLE I WILL STICK WITH CONTINUITY AND ADD NO POPS TO
THE FORECAST. IF THE ECMWF STARTS TO AGREE WITH THAT TRACK...THE
LATER FORECASTS WILL LIKELY BE ADDING POPS LATE NEXT WEEK. 84
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 94 74 93 72 94 / 50 10 10 5 5
WACO, TX 95 74 93 73 96 / 20 10 10 10 10
PARIS, TX 90 72 90 71 92 / 20 10 10 10 10
DENTON, TX 93 74 93 72 93 / 40 10 10 5 5
MCKINNEY, TX 92 73 92 72 94 / 50 10 10 10 10
DALLAS, TX 94 74 93 72 94 / 50 10 10 5 5
TERRELL, TX 93 73 92 71 93 / 50 10 10 10 10
CORSICANA, TX 92 74 92 72 94 / 20 10 20 10 10
TEMPLE, TX 92 75 91 74 93 / 20 10 10 5 10
MINERAL WELLS, TX 93 74 93 72 94 / 30 10 10 5 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
/
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
330 AM CDT FRI JUN 15 2012
.AVIATION...
08Z AMENDMENTS OF 06Z TAFS...A LINE OF SHOWERS AND THUNDERSTORMS HAS
ORGANIZED NORTHWEST OF METROPLEX TAF SITES AND CONTINUES TO HOLD
TOGETHER WHILE MOVING SOUTHEAST AS OF 08Z. THIS LINE OF SHOWERS AND
STORMS WAS MOVING SOUTHEAST AT APPROXIMATELY 20 KTS. USED THIS
SPEED TO AMEND THE TAFS FOR THE WIND SHIFT LINE AND VICINITY THUNDER
FOR NOW...AND WILL UPDATE THE TIMING AGAIN WITH SCHEDULED 09Z
AMENDMENTS.
ASSUMING PRECIPITATION MAINTAINS ITS CURRENT COVERAGE AS IT GETS
CLOSER TO THE METROPLEX...WILL INCLUDE PRECIPITATION WITH MVFR VSBYS
IN ADDITION TO THE VCTS. CONFIDENCE IS HIGH IN A WIND SHIFT
AFFECTING ALL METROPLEX TAF SITES FROM 0930Z TO 1030Z. AT THIS TIME
ALL OF THIS ACTIVITY APPEARS TO BE ELEVATED OVER A STABLE COLD
LAYER/REMNANTS OF EARLIER THUNDERSTORM ACTIVITY. THEREFORE THIS
ACTIVITY IS NOT EXPECTED TO BECOME SEVERE AS IT MOVES OVER METROPLEX
AREA TAF SITES. WILL CONTINUE TO MONITOR RADAR TRENDS AND WILL
UPDATE THE AVIATION DISCUSSION IF ANY MAJOR CHANGE IN THE FORECAST
IS NECESSARY.
CAVANAUGH
&&
.DISCUSSION...
MANY MODELS CONTINUE TO OVER-STABILIZE THE ATMOSPHERE...AND ONCE
AGAIN THE RESULT IS THAT THE ATMOSPHERE RETAINS ENOUGH
INSTABILITY TO SUPPORT CONVECTION. THE SHORT WAVE FEATURES
ASSOCIATED WITH THESE SYSTEMS ARE WEAK...AND IT MAY BE THAT THE
SMOOTHING SCHEMES USED IN MODEL INITIATION ARE DESTROYING THESE
FEATURES THAT ARE PRODUCING WEATHER.
FOR TODAY...THE TTU WRF AND 00Z GFS COMPLETELY MISSED THE ONGOING
CONVECTION. THE HRRR IS NOT AVAILABLE. THE RAP/RUC FAILED TO
ADVECT THE STORMS INTO OUR AREA. OUN WRF AND NCEP 4KM WRF BOTH
FORECAST THE NOCTURNAL CONVECTION TO CONTINUE INTO NORTH TEXAS.
THE NAM PRODUCED NO PRECIPITATION TODAY...BUT CROSS SECTION
ANALYSIS SHOWS INSTABILITY AND MOISTURE ABOVE THE MORNING
INVERSION AND SO IT DOES SUPPORT THE POTENTIAL FOR CONVECTION.
ANOTHER FACTOR IS THE MCV THAT IS CURRENTLY CENTERED JUST WEST OF
FREDERICK AND SHOULD TRACK ACROSS SOUTHERN OKLAHOMA. ANY FORCING
FOR LIFT GENERATED BY THIS FEATURE WILL LIKELY NOT BE RESOLVED IN
THIS MORNING/S MODELS. IT MAY BE THAT WEDNESDAY AFTERNOON/S MCV
THAT TRACKED SIMILARLY TO THIS ONE HAD AN INFLUENCE ON THE NORTH
TEXAS CONVECTION THAT PRODUCED THE LARGE HAIL. THUS I HAVE KEPT
POPS ACROSS THE ENTIRE CWA THIS MORNING AND THE EASTERN THIRD
THIS AFTERNOON. WITH DEW POINTS IN THE LOW TO MID 70S...IT WILL
NOT TAKE MUCH FORCING TO DESTABILIZE THIS ATMOSPHERE.
I CONTINUED THE LOW POPS IN THE SOUTHEAST FOR SATURDAY
AFTERNOON...THEN IT APPEARS THAT NORTH TEXAS WILL REMAIN DRY
THROUGH MONDAY. THE TROPICAL DISTURBANCE THAT WILL MOVE ACROSS THE
GULF EARLY NEXT WEEK STILL HAS THE POTENTIAL TO PRODUCE PRECIP
ACROSS THE SOUTHERN CWA ON TUESDAY AND WEDNESDAY. THIS SCENARIO
IS SUPPORTED BY BOTH THE GFS AND ECMWF. BY THURSDAY...MODELS START
TO DIVERGE. THE GFS NOW TAKES THE TROPICAL DISTURBANCE ON A MUCH
MORE NORTHERN TRACK AND RECURVES IT ACROSS NORTH TEXAS FRIDAY AND
SATURDAY. THE ECMWF HOLDS THE SUBTROPICAL RIDGE TO THE NORTH OF
THE TROPICAL SYSTEM AND SHUNTS IT WESTWARD INTO MEXICO. IF THE GFS
IS RIGHT...THE LATE WEEK TIME PERIODS WILL BE WET BUT SINCE THIS
IS A NEW WRINKLE I WILL STICK WITH CONTINUITY AND ADD NO POPS TO
THE FORECAST. IF THE ECMWF STARTS TO AGREE WITH THAT TRACK...THE
LATER FORECASTS WILL LIKELY BE ADDING POPS LATE NEXT WEEK. 84
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 94 74 93 72 94 / 30 10 10 5 5
WACO, TX 95 74 93 73 96 / 20 10 10 10 10
PARIS, TX 90 72 90 71 92 / 20 10 10 10 10
DENTON, TX 93 74 93 72 93 / 30 10 10 5 5
MCKINNEY, TX 92 73 92 72 94 / 30 10 10 10 10
DALLAS, TX 94 74 93 72 94 / 30 10 10 5 5
TERRELL, TX 93 73 92 71 93 / 20 10 10 10 10
CORSICANA, TX 92 74 92 72 94 / 20 10 20 10 10
TEMPLE, TX 92 75 91 74 93 / 20 10 10 5 10
MINERAL WELLS, TX 93 74 93 72 94 / 30 10 10 5 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1148 PM CDT THU JUN 14 2012
.DISCUSSION...
/SEE BELOW FOR AVIATION DISCUSSION/
&&
.AVIATION...
LARGE STORM COMPLEX NORTH OF ABILENE WILL LIKELY STAY NORTH OF
THE KABI TERMINAL...HOWEVER IT WILL LIKELY SEND AN OUTFLOW
BOUNDARY SOUTHWARD...AND KABI MAY SEE TEMPORARY STRONG NORTHWEST
WINDS 6-8Z. STRATUS POSSIBLE TOWARD SUNRISE AT KJCT...BUT WILL
ONLY ADD A SCATTERED LAYER DUE TO EXPECTED PATCHY NATURE. GUSTY
SOUTH WINDS TO 25 KTS AT KSJT AND KABI WITH CONTINUED STRONG LEE
TROUGH.
&&
.PREV DISCUSSION... /ISSUED 930 PM CDT THU JUN 14 2012/
UPDATE...
UPDATED FOR SEVERE THUNDERSTORM WATCH 394 FOR THE BIG COUNTRY.
DISCUSSION...
STORM COMPLEX EAST OF LUBBOCK WAS DEVELOPING STORMS ON ITS SOUTHERN
END... INDICATING A STRONGER COLD POOL AND SOUTHEASTWARD PUSH.
INCREASED AND ADDED POPS TO THE BIG COUNTRY COUNTIES...ALONG WITH
MENTION OF SEVERE IN ZONES...FOR THUNDERSTORM WATCH UNTIL 3 AM.
04
PREV DISCUSSION... /ISSUED 601 PM CDT THU JUN 14 2012/
DISCUSSION...
SEE 00Z AVIATION DISCUSSION BELOW.
AVIATION...
VFR CONDITIONS ARE EXPECTED THE NEXT 24 HOURS. WATCHING TSTMS
AGAIN OVER THE TRANS PECOS OF SOUTHWEST TEXAS. THESE STORMS ARE
MOVING SLOWLY NORTHEAST AND REDEVELOPING ON THE SOUTHERN FLANK OF
THIS COMPLEX. THE STORMS WILL REMAIN WELL WEST OF THE TERMINALS
THIS EVENING. WINDS WILL BE SOUTH AT 10 TO 15 KNOTS WITH A FEW
GUSTS TO 20 KNOTS.
21
PREV DISCUSSION... /ISSUED 333 PM CDT THU JUN 14 2012/
SHORT TERM...
THIS MORNING...500MB ANALYSIS SHOWED A RIDGE AXIS STRETCHING ROUGHLY
FROM FAR WEST TEXAS INTO NORTHWESTERN OKLAHOMA. FARTHER WEST...A
SHORTWAVE TROUGH WAS ROTATING AROUND THE SOUTHERN SIDE OF A CLOSED
LOW OVER THE SOUTHERN CALIFORNIA COAST. THERE WAS ALSO A SHORTWAVE
ACROSS NORTHWESTERN NM...MOVING TO THE NORTHEAST. AT THE SURFACE...
WE HAVE SOUTH TO SOUTHEASTERLY FLOW WITH SURFACE TROUGHING IN
EASTERN NEW MEXICO SOUTH INTO FAR WEST TEXAS. THE SOUTHERLY FLOW IS
HELPING KEEP MOISTURE IN PLACE ACROSS OUR CWA AS DEWPOINT VALUES
REMAIN IN THE 60S FOR THE MOST PART...WITH KABI SITTING AT 69
DEGREES...AND KBBD AT 70 DEGREES AT 2PM. THE HOT TEMPERATURES AND
HIGH DEWPOINT VALUES ARE CONTRIBUTING TO CAPE VALUES EXCEEDING 4000
J/KG OVER A LARGE PORTION OF THE CWA.
THE QUESTION FOR TONIGHT WILL BE WHETHER OR NOT CONVECTION CAN GET
GOING THIS AFTERNOON TO OUR WEST...AND IF IT WILL IMPACT OUR AREA.
BOTH THE HRRR AND NAM ARE OPTIMISTIC IN TERMS OF RAIN CHANCES FOR
THE SOUTHERN 2/3 OF THE CWA. THE HRRR DEVELOPS A BROKEN LINE OF
THUNDERSTORMS BY 3 OR 4 PM LOCAL TIME...FURTHER DEVELOPING THAT INTO
A SOUTHEASTWARD PROPAGATING MCS THROUGH THE REST OF THE CWA. THE NAM
SHOWS A SIMILAR SCENARIO DEVELOPING QPF ACROSS THE CONCHO VALLEY
DURING THE LATE AFTERNOON AND EVENING...THEN ADDITIONAL QPF FARTHER
SOUTH AND SOUTHEAST DURING THE EVENING HOURS. THE GFS IS COMPLETELY
DRY...AND ECMWF DOES SHOW SOME QPF...WITH THE FOCUS ALONG THE
WESTERN BORDER OF THE CWA. WITH THIS IN MIND...WILL GO WITH A SLIGHT
CHANCE OF SHOWERS AND THUNDERSTORMS FOR GENERALLY THE WESTERN HALF
OF THE CWA. CONSIDERING THE MAGNITUDE OF THE CAPE VALUES...0-6KM
BULK SHEAR VALUES OF 30 TO 40 KNOTS...WE COULD EXPECT TO SEE THESE
STORMS QUICKLY STRENGTHEN AND COULD SEE SOME SEVERE THUNDERSTORMS.
THE MAIN HAZARD WOULD LIKELY BE WIND AS A DRY SUBCLOUD LAYER WILL
RESULT IN AN /INVERTED V/ TYPE SOUNDING AND DECENT DOWNBURST
POTENTIAL. THAT/S ALL DEPENDENT ON WHETHER OR NOT THUNDERSTORMS CAN
DEVELOP. WHILE WE ARE ONLY GOING WITH SLIGHT CHANCE POPS AT THE
MOMENT...IF CONVECTION BEGINS TO RAPIDLY DEVELOP...WE WILL LIKELY
UPDATE THE FORECAST.
FOR TEMPERATURES...HAVE GONE WITH A PERSISTENCE FORECAST FOR THE
MOST PART. NOT EXPECTING A LOT OF PRECIPITATION...HAVE KEPT LOWS
TONIGHT WARMER THAN...BETWEEN THIS MORNING/S LOWS AND THE GUIDANCE
TEMPERATURES. BASICALLY WENT WITH WARMER THAN GUIDANCE FOR HIGHS
TOMORROW...AS WE/VE GENERALLY BEEN WARMER THE LAST FEW DAYS...WHEN
NOT EXPERIENCING PRECIPITATION.
LONG TERM...
FAIRLY WEAK UPPER LEVEL RIDGING TO HOLD THROUGH THE WEEKEND ACROSS
THE SOUTHWEST US...WHILE A WEAK INVERTED TROUGH TRIES TO APPROACH
FROM THE EAST. THIS SETS UP A WEAK SHEAR AXIS WEST OF THE
AREA. THIS MAY BE ENOUGH TO GENERATE SOME CONVECTION...BUT IF IT
DOES DEVELOP...IT WILL LIKELY HAVE A HARD TIME MOVING VERY FAR
EAST. WILL KEEP A DRY FORECAST FOR NOW. OTHERWISE...TEMPERATURES
WILL COOL JUST SLIGHTLY...AS LOW LEVEL FLOW BACKS TO THE
SOUTHEAST AND MOISTURE INCREASES. HAVE BOOSTED OVERNIGHT LOWS A
FEW DEGREES WITH THE MOISTURE INCREASE...WITH AFTERNOON HIGHS
PRETTY CONSISTENT IN THE LOW TO MID 90S.
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 74 95 72 92 73 / 20 10 10 10 10
SAN ANGELO 75 97 74 95 72 / 20 10 10 10 10
JUNCTION 74 95 74 93 72 / 10 0 0 10 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/99/04
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
643 PM CDT SAT JUN 16 2012
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND SUNDAY.
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A WEAK
MID-LEVEL CIRCULATION MOVING NORTHEAST INTO CENTRAL WISCONSIN EARLY
THIS AFTERNOON. A PROMINENT BAND OF SHOWERS AND EMBEDDED
THUNDERSTORMS DEVELOPED AHEAD OF THIS CIRCULATION EARLIER TODAY WHICH
IS NOW MOVING ACROSS NORTHERN AND NORTH-EAST WISCONSIN. MORE
SCATTERED SHOWER ACTIVITY EXISTS OVER WESTERN...CENTRAL...AND
SOUTHERN WISCONSIN. FARTHER UPSTREAM...A STRONG SHORTWAVE OVER THE
DAKOTAS IS DRIVING A COLD FRONT EAST OVER MINNESOTA. STORMS HAVE
STARTED TO DEVELOP ALONG THE FRONT BUT INSTABILITY IS LACKING SO
FAR. THERE IS SOME CLEARING OVER EASTERN MINNESOTA SO SOME
POTENTIAL FOR FURTHER DESTABILIZATION...BUT TEMPS ARE ONLY THE MID
TO UPPER 70S...AND ARE COOLER OVER WISCONSIN SO SEVERE WEATHER IS
NOT EXPECTED TO DEVELOP. AS THESE TWO SYSTEMS MOVE EAST...PRECIP
CHANCES ARE THE MAIN FORECAST CONCERN.
TONIGHT...WEAK SHORTWAVE ACTIVITY THAT IS PASSING ACROSS WISCONSIN
THIS AFTERNOON WILL EXIT TO THE NORTHEAST THIS EVENING. TRACKING
THE CENTER OF THIS CIRCULATION TAKES IT NORTH AND WEST OF THE FOX
VALLEY...SO WILL PLACE THE HIGHEST POPS NORTH OF THIS LINE. CAN
STILL EXPECT MORE SPOTTY ACTIVITY TO THE SOUTH THROUGH EARLY IN THE
EVENING. STRONGER FORCING WILL ARRIVE LATE THIS EVENING INTO THE OVERNIGHT
WHEN A SHORTWAVE OVER THE DAKOTAS DRIVES A COLD FRONT ACROSS THE
STATE. WITH THE WIDESPREAD CLOUD COVER AND SHOWER
ACTIVITY...INSTABILITY HAS BEEN HELD IN CHECK. STILL THOUGH...THE
MODELS ARE SPITTING OUT 300-500 J/KG OF ELEVATED CAPE THIS EVENING
AHEAD OF THE FRONT. BUT WONDER IF WE ARE GOING TO SEE A NORTHERN
WISCONSIN SPLIT...WHERE SHOWERS AND STORMS MOVE TO THE NORTH AND
SOUTH OF THE REGION. WILL KEEP LIKELY POPS OVER NORTH-CENTRAL
WISCONSIN NORTH OF THE MID-LEVEL CIRCULATION AND CHANCE POPS TO THE
SOUTH. IF SOME SORT OF BROKEN LINE OF SHOWERS AND STORMS DOES
DEVELOP THIS AFTERNOON ALONG THE FRONT...FIGURE IT WILL BE WEAKENING
AS MOVES ACROSS THE FORECAST AREA LATE THIS EVENING SINCE
INSTABILITY WILL BE DIMINISHING. THE FRONT WILL BE EXITING THE AREA
BY 09Z AND WILL SEE CLEARING SKIES BEHIND THE FRONT.
SUNDAY...WEAK HIGH PRESSURE WILL MOVE INTO THE REGION ON SUNDAY.
WILL LIKELY SEE DIURNAL CU DEVELOP OVER N-C WISCONSIN WHERE COOLER
TEMPS WILL RESIDE AT 850MB AND THERE IS ENHANCED RH. LOCATIONS TO
THE SOUTH WILL SEE A MOSTLY SUNNY TO PARTLY CLOUDY DAY. HIGHS
RANGING FROM THE UPPER 70S NORTH TO MID 80S SOUTH.
.LONG TERM...SUNDAY NIGHT THROUGH NEXT SATURDAY.
TEMPERATURES SHOULD REMAIN ABOVE NORMAL THROUGH THE MIDDLE OF
NEXT WEEK WITH AN UPPER LEVEL RIDGE ACROSS THE EASTERN CONUS.
MODELS DIFFERED IN HOW QUICKLY THEY TOOK THE CENTRAL CONUS TROUGH
EAST OF THE AREA...RESULTING IN A PERIOD OF DRIER WEATHER.
STORMS ARE EXPECTED TO MOVE INTO CENTRAL WISCONSIN ON SUNDAY
NIGHT...WHILE THE EAST REMAINS DRY. A WARM FRONT WILL MOVE INTO
CENTRAL AND SOUTHERN WISCONSIN ON MONDAY...BRINGING SHOWERS AND
THUNDERSTORMS TO THE AREA. SOME STORMS COULD BECOME SEVERE WITH PLENTY
OF WARM AND MOIST AIR IN PLACE. HEAVY RAINFALL IS ALSO POSSIBLE.
MODELS INDICATED A WEST TO EAST AXIS OF MAX QPF MOVING NORTH ON
TUESDAY INTO TUESDAY NIGHT. HEAVY RAINFALL REMAINS POSSIBLE DURING
THE PERIOD...BUT THE EXACT LOCATION OF THE STORMS IS A BIT UNCERTAIN.
TIMING DIFFERENCES AROUND THE MIDDLE OF THE WEEK WILL RESULT IN A
MORE UNCERTAIN FORECAST...BUT THE LATTER HALF OF THE WEEK SHOULD
GENERALLY BE DRY.
&&
.AVIATION...A COLD FRONT WILL MOVE ACROSS THE AREA DURING THE LATE
EVENING AND EARLY MORNING HOURS. IT WILL BE PRECEDED BY SHOWERS
AND THUNDERSTORMS AND LOCAL IFR CIGS/VSBYS. GOOD FLYING WEATHER
WILL RETURN BY DAYBREAK SUNDAY AFTER THE FRONT GOES BY.
RDM
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
343 PM CDT FRI JUN 15 2012
.SHORT TERM...TONIGHT THROUGH MONDAY
342 PM CDT FRI JUN 15 2012
MAIN FORECAST CONCERNS ARE ON SHOWER AND THUNDERSTORM CHANCES
TONIGHT THROUGH SATURDAY NIGHT. SHOWER/STORM CHANCES RETURN ON
MONDAY.
AT 3 PM...SURFACE OBSERVATIONS SHOWED A STATIONARY FRONT
STRETCHING FROM NEAR IRON MOUNTAIN MICHIGAN SOUTHWEST TO NEAR
WAUSAU WISCONSIN...TO CHARLES CITY IOWA. VISIBLE SATELLITE AND
RADAR SHOWED A MESOSCALE CONVECTIVE VORTEX OVER SOUTHWESTERN IOWA
SLOWLY DRIFTING NORTH.
MAIN FEATURES TO KEEP A CLOSE WATCH ON THIS EVENING INTO THE
OVERNIGHT HOURS ARE THE STATIONARY BOUNDARY STRETCHING ACROSS THE
FORECAST AREA AND THE COMPACT SHORTWAVE AND MCV FEATURE DRIFTING
NORTHEAST ACROSS IOWA. PLAN ON A FEW SHOWERS AND THUNDERSTORMS
NEAR AND ALONG THE BOUNDARY AS THE SHORTWAVE APPROACHES THE
FORECAST AREA. ACCORDING TO THE NAM...DEEP LAYER SHEAR APPEARS
MARGINAL FOR SEVERE THUNDERSTORMS...WITH 0-6 KM SHEAR OF 25-30
KTS. THE RUC TELLS A LITTLE DIFFERENT STORY WITH 0-6 KM SHEAR OF
30 TO 45 KTS. FEEL THAT THE NAM MAY BE UNDER DOING THE SHEAR A BIT
AND NOT REALLY LATCHING ONTO THE STRENGTH OF THE SHORTWAVE MOVING
ACROSS IOWA INTO THE FORECAST AREA. CONVECTION HAS CERTAINLY
HELPED TO REINFORCE THIS WAVE...WITH THE MCV NOTED ALONG THE
SOUTHERN FLANK. IF ENOUGH INSTABILITY IS REALIZED AN ISOLATED SEVERE
STORM OR TWO IS POSSIBLE THIS EVENING WITH HEAVY RAIN...LARGE
HAIL...AND DAMAGING WINDS. IN ADDITION...WILL HAVE TO CONTINUE TO
KEEP A CLOSE WATCH ON THE BOUNDARY FOR NON SUPERCELL TORNADO
POTENTIAL EARLY THIS EVENING IF STORMS REMAIN SURFACED BASED.
LATEST GUIDANCE HAS BACKED OFF ON THE NST PARAMETER...DROPPING
BELOW 1...SO THINKING THE POTENTIAL IS MINIMAL BUT BEARS CLOSE
MONITORING. THE SHORTWAVE IS EXPECTED TO LIFT INTO SOUTHEAST
MINNESOTA AND SOUTHWEST WISCONSIN LATE TONIGHT INTO EARLY SATURDAY
MORNING. MEANWHILE...A VIGOROUS TROUGH WILL PUSH THROUGH THE
DAKOTAS AND HEAD EAST TOWARD THE UPPER MISSISSIPPI VALLEY LATE
TONIGHT INTO SATURDAY MORNING. THE TROUGH WILL PUSH A FRONTAL
BOUNDARY ACROSS THE FORECAST AREA SATURDAY AFTERNOON AND THIS WILL
BE THE MAIN FEATURE TO KEY IN ON FOR SHOWER AND THUNDERSTORM
DEVELOPMENT. THE STATIONARY FRONT WILL LIFT NORTH AND ACT AS A
WARM FRONT AHEAD OF THE APPROACHING TROUGH. THE FRONT IS EXPECTED
TO LIFT NORTH INTO UPPER MICHIGAN AND NORTHERN MINNESOTA BY LATE
FRIDAY MORNING. THIS WILL PLACE THE FORECAST AREA IN WARM...MOIST
SOUTHERLY FLOW. THE LIMITING FACTOR FOR SEVERE THUNDERSTORM
POTENTIAL ON SATURDAY WILL BE THE CLOUD COVER FROM THE COMPACT
SHORTWAVE TRACKING THROUGH THE FORECAST AREA. THIS COMPLICATES THE
FORECAST CONSIDERABLY...WITH CONVECTION POSSIBLY ONGOING AS THE
DAKOTAS TROUGH DRAWS CLOSER SATURDAY AFTERNOON. THE STRONGEST 0-6
KM BULK SHEAR LOOKS TO STAY NORTH OF INTERSTATE 94 AND LAGS BEHIND
THE FRONT. THE NAM CONTINUES TO ADVERTISE 1500 TO 2500 J/KG 0-3 KM
MUCAPE SATURDAY AFTERNOON WITH LITTLE CIN IN PLACE. THE ECMWF
SHOWS MUCH LESS INSTABILITY WITH 0-3 KM MUCAPE FROM 800 TO AROUND
1500 J/KG. THINKING THAT THESE ECMWF VALUES ARE MORE REASONABLE
GIVEN THE EXPECTED CLOUD COVER HINDERING SURFACE HEATING. THINKING
THERE STILL IS A CHANCE AT SEEING ISOLATED STRONG TO SEVERE
STORMS...WITH LARGE HAIL AND DAMAGING WINDS THE MAIN THREATS. WILL
HAVE TO KEEP A CLOSE WATCH ON AREAS THAT HAVE RECEIVED HEAVY
RAINFALL THURSDAY NIGHT...WHERE FLASH FLOODING COULD BE A CONCERN
IF STORMS MOVE OVER THESE LOCATIONS. PLAN ON HIGHS ON SATURDAY
RANGING FROM THE UPPER 80S ACROSS FAR SOUTHWEST WISCONSIN INTO
NORTHEAST IOWA TO THE UPPER 70S TO LOWER 80S ACROSS NORTH CENTRAL
WISCONSIN.
SHOWERS AND THUNDERSTORMS WILL TAPER OFF LATE SATURDAY NIGHT AS THE
FRONT PUSHES THROUGH THE AREA. WEAK HIGH PRESSURE WILL MOVE INTO THE
REGION ON SUNDAY PROVIDING A BRIEF PERIOD OF DRY AND QUIET WEATHER.
UNDER MOSTLY SUNNY SKIES ON SUNDAY...PLAN ON HIGH TEMPERATURES
RANGING FROM THE MID TO UPPER 80S ACROSS FAR SOUTHWEST WISCONSIN TO
THE THE UPPER 70S ACROSS FAR NORTHERN WISCONSIN. ANOTHER TROUGH IS
EXPECTED TO RACE ACROSS THE DAKOTAS SUNDAY NIGHT...PUSHING INTO
THE UPPER MISSISSIPPI RIVER VALLEY LATE SUNDAY NIGHT INTO MONDAY.
RATHER IMPRESSIVE SHEAR AND CAPE PROFILES NORTH OF INTERSTATE 90
MONDAY INTO MONDAY NIGHT. THE FORECAST MODELS ARE HINTING AT THE
POTENTIAL FOR SEVERE THUNDERSTORMS...MAINLY ACROSS NORTHERN
WISCONSIN DURING THE DAY ON MONDAY. NAM FORECAST SOUNDINGS AT KEAN
INDICATE SBCAPE VALUES CLIMBING TO AROUND 3000 J/KG BY MONDAY
AFTERNOON WITH 0-6 KM BULK SHEAR VALUES OF 50 TO POSSIBLY AS HIGH
AS 70 KTS. A FAIRLY STRONG CAP IN PLACE ALONG AND SOUTH OF
INTERSTATE 90 THROUGH LATE MONDAY AFTERNOON...BUT IT THEN WEAKENS
UNDER STRONG SURFACE HEATING. AT THIS TIME THE HIGHEST CHANCES FOR
SHOWERS AND THUNDERSTORMS LOOK TO BE ALONG AND NORTH OF INTERSTATE
94. SOME TIMING DIFFERENCES ON WHEN THE CONVECTION GETS GOING
WHICH WILL HAVE A MAJOR IMPACT ON THE AMOUNT OF INSTABILITY. GIVEN
THE STRENGTH OF THE SHEAR AND THE POTENTIAL FOR VERY STRONG
INSTABILITY...THIS PERIOD BEARS CLOSE MONITORING...ESPECIALLY
NORTH OF INTERSTATE 94 DURING THE DAY ON MONDAY...WITH THE
POTENTIAL FOR THE THREAT TO SHIFT SOUTH OF INTERSTATE 94 MONDAY
EVENING. OTHERWISE...MONDAY WILL BE A RATHER WARM DAY WITH HIGHS
RANGING FROM THE LOWER 90 ACROSS PORTIONS OF NORTHEAST IOWA INTO
SOUTHWEST WISCONSIN...TO THE MID 80S ACROSS NORTHERN WISCONSIN. IT
WILL FEEL MUGGY WITH DEWPOINTS CLIMBING INTO THE UPPER 60S TO
LOWER 70S.
.LONG TERM...MONDAY NIGHT THROUGH FRIDAY
342 PM CDT FRI JUN 15 2012
15.12 MEDIUM RANGE MODELS CONTINUE TO INDICATE A WARM AND
POTENTIALLY ACTIVE WEATHER PATTERN ACROSS THE UPPER MISSISSIPPI
RIVER VALLEY MONDAY NIGHT INTO THURSDAY. THE FORECAST MODELS ARE ALL
HINTING AT SOUTHWEST FLOW ALOFT ACROSS THE REGION. A FRONTAL
BOUNDARY WILL BE POSITIONED ACROSS THE REGION AND WILL BE THE FOCUS
FOR THUNDERSTORM DEVELOPMENT. THERE IS SOME UNCERTAINTY ON EXACTLY
WHERE THIS BOUNDARY WILL SET UP WITH SEVERAL ROUNDS OF CONVECTION
POSSIBLE ACROSS PORTIONS OF THE AREA. THE MODEL CONCENSUS PLACES THE
BOUNDARY NORTH OF INTERSTATE 90 ON TUESDAY SO WILL KEEP THE HIGHEST
SHOWER AND THUNDERSTORM CHANCES ACROSS THESE AREAS. THE 12Z GFS SHOWS
THE BOUNDARY SHIFTING FURTHER NORTHWEST ON WEDNESDAY...BUT THE 12Z
ECMWF BRINGS THE BOUNDARY SOUTHEAST...PLACING IT FROM NORTHEAST IOWA
INTO NORTH CENTRAL WISCONSIN. WILL EDGE THE FORECAST TOWARDS A MODEL
CONSENSUS BLEND MAINTAINING A CHANCE OF SHOWERS AND THUNDERSTORMS
FROM WEDNESDAY INTO THURSDAY. A COLD FRONT IS EXPECTED TO PUSH
ACROSS THE REGION THURSDAY NIGHT INTO FRIDAY WITH COOLER
TEMPERATURES EXPECTED BY FRIDAY. PLAN ON HIGHS FALLING INTO THE 70S
ON FRIDAY IN THE WAKE OF THE FRONT.
&&
.AVIATION...THROUGH 18Z SATURDAY
1245 PM CDT FRI JUN 15 2012
AS OF 18Z...STALLED FRONTAL BOUNDARY WAS DRAPED ACROSS CENTRAL
IOWA INTO SOUTHEAST MINNESOTA. A REMNANT THUNDERSTORM COMPLEX
ACROSS WESTERN IOWA WAS SLOWLY DRIFTING NORTHEAST AND THIS IS THE
FOCUS FOR THE FORECAST CHALLENGE LATE THIS AFTERNOON AND EVENING
AT KRST/KLSE. EXPECTING SCATTERED THUNDERSTORMS TO DEVELOP ACROSS
NORTHERN IOWA AND SOUTHERN MINNESOTA AFTER 22Z. CEILINGS AND
VISIBILITIES SHOULD REMAIN VFR...BUT COULD BRIEFLY DROP TO MVFR IN
ANY STRONGER THUNDERSTORM...MORE LIKELY AT KRST. MOST OF
THUNDERSTORM ACTIVITY SHOULD SUBSIDE BY MID EVENING. FOR SATURDAY
MORNING...SOME OF THE MODEL SOUNDING GUIDANCE /NAM AND GFS/
SUGGEST LOW CLOUDS OR STRATUS DEVELOPING AT KRST AFTER 10Z...WITH
SHALLOW BUT LIGHT BOUNDARY LAYER WINDS AND AMPLE MOISTURE. NOT
CONFIDENT ON THIS SCENARIO...SO HAVE LEFT OUT OF TAFS...BUT
SOMETHING TO MONITOR IN LATER FORECASTS. LOOKING AHEAD...A STRONG
COLD FRONT WILL MOVE ACROSS MINNESOTA SATURDAY AND SCATTERED
SHOWERS AND THUNDERSTORMS ARE EXPECTED IN THE AFTERNOON HOURS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
342 PM CDT FRI JUN 15 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP
AVIATION...ZT
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
256 PM CDT FRI JUN 15 2012
.SHORT TERM...TONIGHT AND SATURDAY.
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW THE STATE OF
WISCONSIN IS LOCATED BETWEEN LOW PRESSURE SYSTEMS THIS
AFTERNOON...ONE OVER NORTHERN ONTARIO...AND ANOTHER ASSOCIATED WITH
AN MCV SPINNING OVER IOWA. A DECAYING FRONT...WHICH SAGGED INTO
NORTHWEST WISCONSIN EARLY THIS MORNING...GENERATED A BROKEN LINE OF
CONVECTION OVER NORTH-CENTRAL WISCONSIN AND THE CENTRAL UPPER PENINSULA.
DESPITE BUILDING INSTABILITY AND DIMINISHING CIN...CONVERGENCE HAS
WEAKENED ENOUGH ALONG THE FRONT THAT HAS PREVENTED ADDITIONAL
SHOWERS AND STORMS FROM DEVELOPING THIS AFTERNOON. WILL LOWER POPS
FOR THE REST OF THE AFTERNOON. BESIDES PRECIP POTENTIAL ASSOCIATED
WITH THE MCV TOMORROW MORNING...THE MAIN FORECAST CONCERN WILL BE
SEVERE WEATHER POTENTIAL LATE TOMORROW AFTERNOON WHEN COLD FRONT
OVER MONTANA APPROACHES THE STATE.
TONIGHT...PWAT AXIS WILL REMAIN IN PLACE FROM SW TO N-C WISCONSIN
THIS EVENING BUT INSTABILITY AND MID-LEVEL CONVERGENCE WILL BE
WEAKENING. WILL KEEP AN ISOLATED MENTION FOR THE EVENING HOURS. IN
ADDITION...LOW LEVEL WINDS WILL BE BACKING AS A REMNANT MCV SLOWLY
TRACKS INTO SW WISCONSIN BY 12Z. AMPLE DRY AS NOTED ON THE 850MB
RAOBS OVER ILLINOIS WILL SWING NORTH AND CUTOFF ANY PRECIP CHANCES
EXCEPT FOR THE FAR WESTERN FORECAST AREA. THERE IS A SMALL CHANCE
THAT SOME PRECIP FROM THE MCV COULD REACH INTO MARSHFIELD AND
WISCONSIN RAPIDS BY 12Z. OTHERWISE...THERE SHOULD BE A STEADY
STREAM OF MID AND HIGH CLOUDS ACROSS THE FORECAST AREA TO MAKE FOR A
PARTLY TO MOSTLY CLOUDY NIGHT...THOUGH NE PARTS MAY START OUT MOSTLY
CLEAR. SHOULD SEE A WARM NIGHT ON TAP WITH LOWS IN THE 60S.
SATURDAY...REMNANT MCV OVER IOWA WILL SLOWLY PICK UP SPEED AS IT
MOVES TO THE NE OVER WISCONSIN. BECAUSE THE INITIAL AIRMASS WILL BE
SO DRY IN THE LOW TO MID-LEVELS...THE MCV SHOULD BRING AN INFLUX OF
850MB THETAE TO CENTRAL AND NORTH-CENTRAL WISCONSIN DURING THE
MORNING...WHERE WILL KEEP MEDIUM CHANCE POPS IN THE FORECAST.
DURING THE AFTERNOON...ANOTHER WEAK WAVE (NOW OVER WESTERN KANSAS)
WILL LIFT ACROSS NORTHWEST WISCONSIN. THIS WAVE WILL INTERACT WITH
AN 850MB THETAE AXIS WHICH WILL MOVE INTO THE STATE AHEAD OF A COLD
FRONT. HARD TO SAY HOW MUCH AFTERNOON INSTABILITY WILL BE
PRESENT...DUE TO THE POSSIBILITY OF MORNING SHOWERS AND STORMS FROM
THE MCV. THE SPC SREF DOES SUGGEST THE POSSIBILITY OF 1000-1250
J/KG OF ML CAPE OVER N-C WISCONSIN...WHERE LARGE-SCALE ASCENT WILL
ARRIVE BY LATE AFTERNOON. COULDNT MODIFY NAM/GFS SOUNDINGS AS THEY
LOOKED MODIFIED BY THEIR CONVECTIVE PARAMETERIZATION SCHEMES. IF
THE INSTABILITY DOES MATERIALIZE...30-35KTS OF 0-6KM SHEAR SUGGEST
COULD SEE A FEW ORGANIZED STORMS...WITH THE POTENTIAL FOR STRONG
WINDS AND LARGE HAIL. THE FREEZING LEVEL IS QUITE HIGH THOUGH
(14.5KFT)...SO COULD BE MORE OF A WIND THREAT THAN ANYTHING ELSE.
HIGHS IN THE EAST COULD GET QUITE TOASTY AGAIN...ASSUMING PRECIP
DOES NOT MAKE IT IN THERE. WILL GO WITH NEAR 90 HIGHS OVER THE FOX
VALLEY...TO THE LOWER 80S OVER N-C WISCONSIN WHERE THE POSSIBILITY
OF MORE WIDESPREAD CLOUDS/SHOWERS/STORMS WILL RESIDE.
.LONG TERM...SATURDAY NIGHT THROUGH NEXT FRIDAY.
MODELS CONTINUED TO SHOW A WET PATTERN FOR NORTHEAST WISCONSIN
DURING THIS PART OF THE FORECAST. THERE APPEARED TO BE DECENT
AGREEMENT AMONG THE MODELS...SHOWING A MID LEVEL SHORT WAVE AND
SURFACE COLD FRONT BRINGING SHOWERS AND THUNDERSTORMS TO THE AREA
SATURDAY NIGHT. STILL LOOKED SHOWERS/STORMS WILL BE GONE BY EARLY
SUNDAY...RESULTING IN A DRY DAY WITH A SURFACE RIDGE OVER THE AREA
AND A WEAK MID LEVEL RIDGE PASSING THROUGH WISCONSIN.
THUNDERSTORM CHANCES RETURN IN THE WEST LATE SUNDAY NIGHT. PLENTY
OF WARM AND HUMID AIR AHEAD OF AN APPROACHING COLD FRONT WILL
BRING THUNDERSTORMS TO THE ENTIRE AREA BY LATE MONDAY...LASTING
INTO MONDAY NIGHT AS THE FRONT PASSES.
MODELS NOT AS CONSISTENT WITH THE REST OF THE FORECAST SO HAVE
MADE NO MORE THAN MINOR TWEAKS FOR TUESDAY THROUGH FRIDAY.
&&
.AVIATION...VFR CONDITIONS EXPECTED TODAY WITH PRIMARILY RESIDUAL
MID TO HIGH-LEVEL CLOUDS FROM A DISTURBANCE OVER THE PLAINS. WEAK
SURFACE TROUGH APPROACHING THE FAR WESTERN PORTION OF THE FORECAST
AREA THIS AFTERNOON...ALONG WITH INCREASING INSTABILITY MAY CONTRIBUTE TO THE
DEVELOPMENT OF SCATTERED AND POORLY ORGANIZED SHOWER AND
THUNDERSTORM ACTIVITY. RHI STANDS THE BEST CHANCE FOR SEEING ANY
CONVECTIVE ACTIVITY THAT DOES DEVELOP. AS ACTIVITY WILL BE SCATTERED
IN NATURE...DID NOT EXPLICITLY MENTION IN TAFS. MID-LEVEL
CONVECTIVELY INDUCED CIRCULATION IN WESTERN IOWA WILL APPROACH
WISCONSIN OVERNIGHT AND MAY GENERATE MORE ORGANIZED CONVECTION...BUT
EXACT TIMING AND LOCATION OF THUNDERSTORM ACTIVITY THAT MAY
ACCOMPANY WITH THIS FEATURE IS STILL IN QUESTION. BEST GUESS IS
THAT ANY THUNDERSTORM ACTIVITY WILL GENERALLY REMAIN SOUTH AND WEST
OF THE FORECAST AREA UNTIL AFTER 15Z SATURDAY.
MPC
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MPC/MG
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1245 PM CDT FRI JUN 15 2012
.SHORT TERM...THROUGH SUNDAY NIGHT
427 AM CDT FRI JUN 15 2012
THE FIRST TWO DAYS OF THIS PERIOD ARE TOUGH...WITH LITTLE FORCING
TO ANCHOR FORECAST CONFIDENCE ON. COLD FRONT BLASTING THROUGH
SATURDAY NIGHT PROVIDES A BETTER TARGET FOR CLARITY.
AT 08Z A TROUGH RAN NORTH TO SOUTH THROUGH MN WITH SOUTHEAST FLOW
BECOMING MORE UNIFORM ACROSS THE FORECAST AREA. THE
TROUGH IN MN IS A SOUTHWARD EXTENSION OF THE TROUGH FROM THE
SURFACE LOW NORTH OF LAKE WINNIPEG. THIS TROUGH IS REPRESENTED IN
THE LOW-LEVELS AS WELL...ALL PART OF THE SPOKE OF ENERGY ROTATING
EAST NEAR KINL. SOME LOWER DEW POINTS WERE NOTED ACROSS THE SOUTH
AND EAST...IN THE 50S. OVER THE PAST HOURS THE RADAR OVER THE
FORECAST AREA CONTINUES TO SHOW A DECREASING SHOWER TREND AND
CLOUD TOPS CONTINUE TO WARM. MASSIVE CONVECTIVE COMPLEX IN CENTRAL
U.S. SHOWING SIGNS OF WEAKENING...AND RADAR INDICATES A WELL-
DEFINED SPIN IN SERN NEBRASKA...THE FORECAST PROBLEM FOR TONIGHT.
00Z RAOBS WERE INFORMATIVE WITH LOW-LEVEL MOIST PLUME ALONG A
KMPX-KOMA LINE WITH DEW POINTS AT 850MB NEAR 15C..RATHER
IMPRESSIVE. SO IS THE GRADIENT SOUTHEASTWARD INTO ERN WI/ERN
IA/IL WITH DEWPOINTS NEAR 0-3C. VERY DRY TOO AT 700MB FROM KOLZ-
KDLL SOUTHEAST...YIELDING THE RAIN/TSRA EASTERN EXTENT OVERNIGHT.
NEXT WEATHER SYSTEM FOR SATURDAY MAKING ITS WAY EAST AND CLEARLY
SEEN IN THE WATER VAPOR IMAGERY ON THE SOUTHERNMOST BORDER OF
ALBERTA AND BRITISH COLUMBIA BORDER. NCEP RAP MODEL ANALYZED THIS
TIGHT/DEEP S/WV TROPOPAUSE LEVEL DOWN TO 500MB.
WITH MOISTURE PLUME TO THE NORTHWEST AND LAYING OVER THE NORTHWEST
FORECAST AREA...AND CONTINUED MOIST FLOW...AND THE TROUGH SHIFTING
EAST...HAVE DECIDED TO KEEP AN ISOLATED TSRA OVER THE AREA THIS
MORNING. SPC MUCAPE ANALYSIS SHOWS SOME WEAK INSTABILITY /1000
J/KG/ STILL IS PRESENT IN THE MOIST PLUME. BY THE AFTERNOON...THERE
IS SOME MODEL CONSENSUS THAT THE TROUGH WILL LIE FROM ABOUT KAUW
TO KCCY...AND WITH CLEARING SKIES THIS MORNING FOR THE MOST
PART...BELIEVE SBCAPE SHOULD BE NEAR 2000J/KG. THUS...HAVE KEPT
MID-RANGE RAIN CHANCES FOR CONVECTION DEVELOPING THIS AFTERNOON.
WITH MARGINAL SHEAR...CANNOT RULE OUT A SEVERE STORM OR TWO WITH
WIND OR HAIL THE THREATS. HAVE ALSO ASSESSED THE NON-SUPERCELL
TORNADO THREAT AND WHILE THE BOUNDARY IS NEARLY STATIONARY...THE
WIND FLOW IS QUITE WEAK AND THE LOW-LEVELS NOT QUITE UNSTABLE
ENOUGH TO HAVE CONFIDENCE IN THIS OUTCOME. IT COULD BE
POSSIBLE...BUT WOULD THINK FUNNELS WOULD BE SEEN WITH PARAMETER
SPACE /PER 15.06 RAP AND NAM/ NOT TOO HIGH FOR TORNADOES.
TONIGHT IS DIFFICULT. THE NCEP SUITE OF MODELS HAVE HAD A CONSENSUS
THAT A CONVECTIVELY-ENHANCED SHORTWAVE TROUGH WILL MOVE NORTHEAST
THROUGH THE FORECAST AREA OVERNIGHT...AND WE BELIEVE THIS IS THE
ROTATION IN SERN NEB AT 08Z. THE 15.00Z NAM/GFS/ECMWF/CANADIAN NRN
HEMI ALL HAVE THIS FEATURE MOVING ACROSS THE FORECAST AREA
OVERNIGHT. THIS WOULD BE DURING A TIME PERIOD OF LOWER MUCAPE
/LESS THAN 500 J/KG/ AND S/WV TROUGH WOULD TRACK EAST OF MAIN
MOIST PLUME WHICH DOESNT MOVE MUCH TODAY. OVERALL...THIS COULD BE
ANOTHER RAIN THREAT AND BRING RAIN TO MOST...BUT THE TIMING TOO IS
IN QUESTION AS TO HOW THIS WAVE GETS ABSORBED INTO THE FLOW.
CONFIDENCE IS LOW ON THIS TARGET AND TIMING...BUT DAY SHIFT SHOULD
BE ABLE TO SEE CONVECTION ENHANCING ACROSS IA THIS AFTERNOON AND
BETTER REFINE TONIGHTS FORECAST.
FINALLY ON SATURDAY THE B.C. S/WV TOUGH IMPACTS THE REGION WITH A
COLD FRONTAL PASSAGE LATE AFTERNOON AND EVENING. A FAIRLY
IMPRESSIVE MOIST POOL IS PRESENT AHEAD OF THIS FRONT AND WITH
TIMING NEAR PEAK HEATING...SBCAPE WOULD APPROACH 1500 J/KG.
HOWEVER...WIND FIELDS SUGGEST SHEAR IS WEAK WHICH SHOULD LIMIT
ORGANIZED THREATS FOR SEVERE WEATHER. WHILE FORCING IS A BIT
STRONGER...SEEMS ISOLATED SEVERE WOULD BE THE CALL. MAYBE FURTHER
NORTH WHERE MID-LEVEL FLOW IS A BIT STRONGER...WIND SHEAR WOULD
SUPPORT A SLIGHTLY BETTER STORM THREAT. POST FRONTAL AIR MASS
RACES IN SUNDAY AND HAVE REMOVED RAIN CHANCES THERE. ALSO SHIFTED
THE SATURDAY NIGHT RAIN CHANCES EAST FASTER.
SUNDAY NIGHT ALSO NEEDS TO BE WATCHED AS THE FRONTAL BOUNDARY THAT
PASSES SATURDAY NIGHT RETURNS WITH GUSTO AS A WARM FRONT. FOR
EXAMPLE...850 MB DEWPOINTS JUMP FROM LESS THAN 0C TO 14C WITHIN 6
HOURS. THESE RAPID ADVECTIONS SCREAM IMBALANCE TO ME AND CONVECTIVE
CHANCES ARE IN THE FORECAST.
.LONG TERM...MONDAY THROUGH THURSDAY NIGHT
427 AM CDT FRI JUN 15 2012
THIS PERIOD IS CHARACTERIZED BY DEEPENING BROAD LONG WAVE TROUGH
OVER THE WESTERN U.S. AND A RETURN TO HEAT IT APPEARS. MOISTURE
AND HEAT WILL BUILD IN AFTER THE WARM FRONTAL PASSAGE SUNDAY NIGHT
TO THE NORTH WITH A COLD FRONT SLOWLY STALLING OVER THE AREA FOR
TUESDAY. SOUTH OF THE FRONT IT WILL BE WARM AND HUMID WITH COOLER
RAIN CHANCES NORTH OF THE FRONT. TUESDAY APPEARS TO BE THE
CONSENSUS RAIN DAY WITH A SLOW MOVING EAST-WEST BOUNDARY OVER THE
AREA AND HIGH CAPE BUILDING TO THE SOUTH. MOST MODELS MOVE THIS
NORTHWARD ON WEDNESDAY WHICH WOULD MEAN HOT AND HUMID ALL AREAS
AND CAPPING INVERSION IN PLACE. HAVE INCREASED TEMPERATURES OVER A
CONSENSUS MODEL FORECAST ACROSS THE SOUTHERN FORECAST AREA MONDAY-
WEDNESDAY AS WE SHOULD BE WELL ABOVE GUIDANCE. WITH THE BOUNDARY
MOVING NORTH WEDNESDAY...FLOODING RAINS SHOULD NOT BE A
PROBLEM...AND TUESDAYS RAIN WILL LIKELY BE WELCOMED. DETAILS ON
EXACTLY WHERE THIS WILL OCCUR ARE STILL OF LOW CONFIDENCE...BUT A
CONSISTENT I-90 SIGNAL IS A MODEL CONSENSUS.
&&
.AVIATION...THROUGH 18Z SATURDAY
1245 PM CDT FRI JUN 15 2012
AS OF 18Z...STALLED FRONTAL BOUNDARY WAS DRAPED ACROSS CENTRAL
IOWA INTO SOUTHEAST MINNESOTA. A REMNANT THUNDERSTORM COMPLEX
ACROSS WESTERN IOWA WAS SLOWLY DRIFTING NORTHEAST AND THIS IS THE
FOCUS FOR THE FORECAST CHALLENGE LATE THIS AFTERNOON AND EVENING
AT KRST/KLSE. EXPECTING SCATTERED THUNDERSTORMS TO DEVELOP ACROSS
NORTHERN IOWA AND SOUTHERN MINNESOTA AFTER 22Z. CEILINGS AND
VISIBILITIES SHOULD REMAIN VFR...BUT COULD BRIEFLY DROP TO MVFR IN
ANY STRONGER THUNDERSTORM...MORE LIKELY AT KRST. MOST OF
THUNDERSTORM ACTIVITY SHOULD SUBSIDE BY MID EVENING. FOR SATURDAY
MORNING...SOME OF THE MODEL SOUNDING GUIDANCE /NAM AND GFS/
SUGGEST LOW CLOUDS OR STRATUS DEVELOPING AT KRST AFTER 10Z...WITH
SHALLOW BUT LIGHT BOUNDARY LAYER WINDS AND AMPLE MOISTURE. NOT
CONFIDENT ON THIS SCENARIO...SO HAVE LEFT OUT OF TAFS...BUT
SOMETHING TO MONITOR IN LATER FORECASTS. LOOKING AHEAD...A STRONG
COLD FRONT WILL MOVE ACROSS MINNESOTA SATURDAY AND SCATTERED
SHOWERS AND THUNDERSTORMS ARE EXPECTED IN THE AFTERNOON HOURS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
427 AM CDT FRI JUN 15 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BAUMGARDT
LONG TERM...BAUMGARDT
AVIATION...ZT
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1234 PM CDT FRI JUN 15 2012
UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE
.SHORT TERM...TODAY THROUGH SATURDAY.
ANOTHER CHALLENGING FORECAST IN THE SHORT-TERM.
WATER VAPOR IMAGERY AND RAP ANALYSIS EARLY THIS MORNING SHOW
PRIMARY SHORTWAVE CONTINUING TO LIFT NORTHEAST TOWARD SOUTHERN
HUDSON BAY. ASSOCIATED CONVECTIVE ACTIVITY THAT DEVELOPED LATE
YESTERDAY OVER SE MINNESOTA AND WESTERN WISCONSIN PUSHED INTO
CENTRAL WISCONSIN OVERNIGHT AND HAS FINALLY ALL BUT DISSIPATED.
PERSISTENT STRATIFORM RAIN AREA AND ASSOCIATED EVAPORATIVE LOW-
LEVEL COOLING ALLOWED FOR WELL DEVELOPED MESO-HIGH...WITH
SUBSEQUENT SFC WAKE-LOW DEVELOPMENT ON NORTHERN PERIPHERY OF
STRATIFORM RAIN SHIELD. SOUTHERLY ISALLOBARIC WIND ACCELERATIONS
LEAD TO SURFACE WIND GUSTS TO 45 TO 50 MPH OVER PARTS OF
MARATHON...ONEIDA...WESTERN SHAWANO AND NORTHERN WOOD COUNTIES
AROUND MIDNIGHT. SOME SMALL TREES AND POWERLINES WERE BLOWN DOWN
ACROSS THIS AREA RESULTING IN SCATTERED POWER OUTAGES.
STILL SOME SCATTERED SHOWER ACTIVITY ASSOCIATED WITH REMNANT MID-
LEVEL CONVECTIVELY INDUCED CIRCULATION OVER MAINLY CENTRAL
WISCONSIN THIS MORNING. EXPECT SCATTERED MAINLY LIGHT SHOWER
ACTIVITY AND PERHAPS AN ISOLATED THUINDERSTORM TO GRADUALLY WANE
AND MOVE NORTHEAST DURING THE MORNING. ADDITIONAL SHOWER AND
THUNDERSTORM ACTIVITY FOR THE REMINADER OF THE DAY WILL MOST
LIKELY BE FOCUSED ALONG RESIDIAL CONVECTIVE OUTFLOW BOUNDARIES AND
WEAKENING FRONTAL BOUNDARY NOW ENTERING NORTHWEST WISCONSIN.
FRONTAL BOUNDARY IS FORECAST TO REMIAN QUASI-STATIONARY OR PERHAPS VERY
SLOWLY DRIFT SOUTHEAST INTO THE FORECAST AREA LATE TODAY AND
CONTINUE TO WEAKEN...THUS HARD TO PIN DOWN MOST LIKELY AREA OF
SUFFICIENT BOUNDARY LAYER CONVERGENCE TO INITIATE CONVECTION THIS
AFTERNOON. BEST GUESS WOULD BE MAINLY NORTHWEST OF THE FOX VALLEY
ACROSS CENTRAL AND NORTHERN WISCONSIN. AMOUNT OF ACTIVITY WILL
ALSO DEPEND ON THE AMOUNT OF INSOLATION AND DESTABLIZATION. BASED
ON CURRENT CLOUD TRENDS...FEEL SHOULD SEE SOME SUNSHINE TODAY TO
ALLOW MLCAPES TO CLIMB INTO THE 1000-1500 J/KG RANGE. ALTHOUGH
DEEP LAYER SHEAR WILL WEAKEN SOME DURING THE COURSE OF THE DAY AS
UPPER-LEVEL HEIGHTS TRY TO BUILD OVER THE AREA...VALUES WILL
STILL BE MARGINALLY SUPPORTIVE OF SUSTAINING STRONGER UPDRAFTS
ACROSS CENTRAL INTO NORTHERN WISCONSIN TODAY. PRIMARY THREAT WITH
ANY STRONGER STORMS THAT CAN FORM THIS AFTERNOON WOULD BE
MARGINALLY SEVERE HAIL AND GUSTY WINDS.
MAIN FORECAST PROBLEM OVERNIGHT TONIGHT INTO SATURDAY WILL BE WHAT
HAPPENS WITH CONVECTIVELY INDUCED CIRCULATION NOW LOCATED OVER
EASTERN NEBRASKA. CURRENT RADAR TRENDS SUGGEST CIRCULATION IS
SLOWELY DRIFTING NORTHWARD INTO EXTREME WESTERN IOWA. MODELS
SUGGEST THIS FEATURE WILL GRADUALLY BE LIFTED NORTHEAST TOWARD THE
WESTERN GREAT LAKES AS PRIMARY SHORTWAVE MOVES EASTWARD ACROSS THE
US-CANADA BORDER TO NEAR LAKE WINNEPEG BY 12Z SATURDAY.
ECMWF...GEM AND NAM SUGGEST A SLOWER AND MORE NORTHERN
TRACK...TAKING THE MCV MORE TO THE WEST OF THE FORECAST AREA. GFS
CONTINUES TO BE THE MOST AGRESSIVE WITH A MORE NORTHEAST TRACK
INTO THE FORECAST AREA AFTER MIDNIGHT. BASED ON CURRENT RADAR
TRENDS AND THAT THE GFS SEEMS TO BE THE OUTLIER...FEEL MORE
FOCUSED CONVECTIVE ACTIVITY WITH THIS FEATURE WILL NOT AFFECT THE
FORECAST AREA UNTIL AFTER 12Z SATURDAY...THUS WAS MORE
CONSERVATIVE ON POPS OVERNIGHT. AS PRIMARY SHORTWAVE CONTINUES
ITS TRACK EASTWARD TOWARD THE WESTERN GREAT LAKES ON SATURDAY
AFTERNOON...IT WILL DRAW MORE UNSTABLE AIRMASS INTO THE FORECAST
AREA INCREASING THE CHANCE FOR MORE WIDESPREAD CONVECTION
ESPECIALLY WEST OF THE FOX VALLEY. THIS ACTIVITY SHOULD BEGIN TO MOVE
INTO THE EASTERN PART OF THE FORECAST AREA TOWARD EVENING ASSUMING
IT CAN OVERCOME DRIER AIR STILL IN PLACE OVER LOWER MICHIGAN AND
EASTERN WISCONSIN.
MAX TEMPS TODAY AND SATURDAY WILL AGAIN BE TRICKY DEPENDING ON
AMOUNT OF CLOUD COVER...THUS USED A MODEL BLEND. BOTTOM LINE IS
THAT TEMPS WILL NOTABLY BE ABOVE NORMAL WITH READINGS APPROACHING
90 DEGREES WHERE GREATEST SUNSHINE CAN OCCUR. MOST LIKELY AREA TO
SEE TEMPS PUSH 90 WOULD BE ACROSS THE SOUTHERN PORTION OF THE
FORECAST AREA.
.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY.
FORECAST AREA WILL BE IN THE RING OF FIRE THROUGH MUCH OF THE WEEK
AS 500 MB RIDGE SETS UP ACROSS THE EASTERN UNITED STATES. THERE
WILL BE PERIODIC CHANCES FOR THUNDERSTORMS THROUGH MUCH OF THE
WEEK. FRONTAL BOUNDARY LOCATION WILL PROBABLY MEANDER ACROSS THE
AREA AS COMPLEX OF STORMS IS EXPECTED TO PUSH BOUNDARY SOUTH AS
THE COMPLEX MOVES ACROSS THE AREA. BOUNDARY EXPECTED TO PUSH
NORTHWARD AGAIN DUE TO SOUTHERLY FLOW BEFORE NEXT COMPLEX OF
STORMS MOVES ACROSS THE REGION. THERE DOES APPEAR TO BE A TRANQUIL
PERIOD SUNDAY AS COMPLEX OF STORMS MOVES EAST OF THE AREA LATE
SATURDAY NIGHT OR EARLY SUNDAY MORNING. TEMPERATURES WILL BE WELL
ABOVE NORMAL DURING THE PERIOD...BUT HOW FAR ABOVE NORMAL WILL BE
DETERMINED BY TIMING OF THE COMPLEXES OF STORMS/CLOUDS MOVING
ACROSS THE AREA. IT APPEARS WEDNESDAY WILL BE PROBABLY THE WARMEST
DAY AS FRONT PUSHES NORTH OF THE AREA.
&&
.AVIATION...VFR CONDITIONS EXPECTED TODAY WITH PRIMARILY RESIDUAL
MID TO HIGH-LEVEL CLOUDS FROM A DISTURBANCE OVER THE PLAINS. WEAK
SURFACE TROUGH APPROACHING THE FAR WESTERN PORTION OF THE FORECAST
AREA THIS AFTERNOON...ALONG WITH INCREASING INSTABILITY MAY CONTRIBUTE TO THE
DEVELOPMENT OF SCATTERED AND POORLY ORGANIZED SHOWER AND
THUNDERSTORM ACTIVITY. RHI STANDS THE BEST CHANCE FOR SEEING ANY
CONVECTIVE ACTIVITY THAT DOES DEVELOP. AS ACTIVITY WILL BE SCATTERED
IN NATURE...DID NOT EXPLICITLY MENTION IN TAFS. MID-LEVEL
CONVECTIVELY INDUCED CIRCULATION IN WESTERN IOWA WILL APPROACH
WISCONSIN OVERNIGHT AND MAY GENERATE MORE ORGANIZED CONVECTION...BUT
EXACT TIMING AND LOCATION OF THUNDERSTORM ACTIVITY THAT MAY
ACCOMPANY WITH THIS FEATURE IS STILL IN QUESTION. BEST GUESS IS
THAT ANY THUNDERSTORM ACTIVITY WILL GENERALLY REMAIN SOUTH AND WEST
OF THE FORECAST AREA UNTIL AFTER 15Z SATURDAY.
MPC
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
651 AM CDT FRI JUN 15 2012
UPDATED AVIATION PORTION FOR 12Z TAF ISSUANCE
.SHORT TERM...TODAY THROUGH SATURDAY.
ANOTHER CHALLENGING FORECAST IN THE SHORT-TERM.
WATER VAPOR IMAGERY AND RAP ANALYSIS EARLY THIS MORNING SHOW
PRIMARY SHORTWAVE CONTINUING TO LIFT NORTHEAST TOWARD SOUTHERN
HUDSON BAY. ASSOCIATED CONVECTIVE ACTIVITY THAT DEVELOPED LATE
YESTERDAY OVER SE MINNESOTA AND WESTERN WISCONSIN PUSHED INTO
CENTRAL WISCONSIN OVERNIGHT AND HAS FINALLY ALL BUT DISSIPATED.
PERSISTENT STRATIFORM RAIN AREA AND ASSOCIATED EVAPORATIVE LOW-
LEVEL COOLING ALLOWED FOR WELL DEVELOPED MESO-HIGH...WITH
SUBSEQUENT SFC WAKE-LOW DEVELOPMENT ON NORTHERN PERIPHERY OF
STRATIFORM RAIN SHIELD. SOUTHERLY ISALLOBARIC WIND ACCELERATIONS
LEAD TO SURFACE WIND GUSTS TO 45 TO 50 MPH OVER PARTS OF
MARATHON...ONEIDA...WESTERN SHAWANO AND NORTHERN WOOD COUNTIES
AROUND MIDNIGHT. SOME SMALL TREES AND POWERLINES WERE BLOWN DOWN
ACROSS THIS AREA RESULTING IN SCATTERED POWER OUTAGES.
STILL SOME SCATTERED SHOWER ACTIVITY ASSOCIATED WITH REMNANT MID-
LEVEL CONVECTIVELY INDUCED CIRCULATION OVER MAINLY CENTRAL
WISCONSIN THIS MORNING. EXPECT SCATTERED MAINLY LIGHT SHOWER
ACTIVITY AND PERHAPS AN ISOLATED THUINDERSTORM TO GRADUALLY WANE
AND MOVE NORTHEAST DURING THE MORNING. ADDITIONAL SHOWER AND
THUNDERSTORM ACTIVITY FOR THE REMINADER OF THE DAY WILL MOST
LIKELY BE FOCUSED ALONG RESIDIAL CONVECTIVE OUTFLOW BOUNDARIES AND
WEAKENING FRONTAL BOUNDARY NOW ENTERING NORTHWEST WISCONSIN.
FRONTAL BOUNDARY IS FORECAST TO REMIAN QUASI-STATIONARY OR PERHAPS VERY
SLOWLY DRIFT SOUTHEAST INTO THE FORECAST AREA LATE TODAY AND
CONTINUE TO WEAKEN...THUS HARD TO PIN DOWN MOST LIKELY AREA OF
SUFFICIENT BOUNDARY LAYER CONVERGENCE TO INITIATE CONVECTION THIS
AFTERNOON. BEST GUESS WOULD BE MAINLY NORTHWEST OF THE FOX VALLEY
ACROSS CENTRAL AND NORTHERN WISCONSIN. AMOUNT OF ACTIVITY WILL
ALSO DEPEND ON THE AMOUNT OF INSOLATION AND DESTABLIZATION. BASED
ON CURRENT CLOUD TRENDS...FEEL SHOULD SEE SOME SUNSHINE TODAY TO
ALLOW MLCAPES TO CLIMB INTO THE 1000-1500 J/KG RANGE. ALTHOUGH
DEEP LAYER SHEAR WILL WEAKEN SOME DURING THE COURSE OF THE DAY AS
UPPER-LEVEL HEIGHTS TRY TO BUILD OVER THE AREA...VALUES WILL
STILL BE MARGINALLY SUPPORTIVE OF SUSTAINING STRONGER UPDRAFTS
ACROSS CENTRAL INTO NORTHERN WISCONSIN TODAY. PRIMARY THREAT WITH
ANY STRONGER STORMS THAT CAN FORM THIS AFTERNOON WOULD BE
MARGINALLY SEVERE HAIL AND GUSTY WINDS.
MAIN FORECAST PROBLEM OVERNIGHT TONIGHT INTO SATURDAY WILL BE WHAT
HAPPENS WITH CONVECTIVELY INDUCED CIRCULATION NOW LOCATED OVER
EASTERN NEBRASKA. CURRENT RADAR TRENDS SUGGEST CIRCULATION IS
SLOWELY DRIFTING NORTHWARD INTO EXTREME WESTERN IOWA. MODELS
SUGGEST THIS FEATURE WILL GRADUALLY BE LIFTED NORTHEAST TOWARD THE
WESTERN GREAT LAKES AS PRIMARY SHORTWAVE MOVES EASTWARD ACROSS THE
US-CANADA BORDER TO NEAR LAKE WINNEPEG BY 12Z SATURDAY.
ECMWF...GEM AND NAM SUGGEST A SLOWER AND MORE NORTHERN
TRACK...TAKING THE MCV MORE TO THE WEST OF THE FORECAST AREA. GFS
CONTINUES TO BE THE MOST AGRESSIVE WITH A MORE NORTHEAST TRACK
INTO THE FORECAST AREA AFTER MIDNIGHT. BASED ON CURRENT RADAR
TRENDS AND THAT THE GFS SEEMS TO BE THE OUTLIER...FEEL MORE
FOCUSED CONVECTIVE ACTIVITY WITH THIS FEATURE WILL NOT AFFECT THE
FORECAST AREA UNTIL AFTER 12Z SATURDAY...THUS WAS MORE
CONSERVATIVE ON POPS OVERNIGHT. AS PRIMARY SHORTWAVE CONTINUES
ITS TRACK EASTWARD TOWARD THE WESTERN GREAT LAKES ON SATURDAY
AFTERNOON...IT WILL DRAW MORE UNSTABLE AIRMASS INTO THE FORECAST
AREA INCREASING THE CHANCE FOR MORE WIDESPREAD CONVECTION
ESPECIALLY WEST OF THE FOX VALLEY. THIS ACTIVITY SHOULD BEGIN TO MOVE
INTO THE EASTERN PART OF THE FORECAST AREA TOWARD EVENING ASSUMING
IT CAN OVERCOME DRIER AIR STILL IN PLACE OVER LOWER MICHIGAN AND
EASTERN WISCONSIN.
MAX TEMPS TODAY AND SATURDAY WILL AGAIN BE TRICKY DEPENDING ON
AMOUNT OF CLOUD COVER...THUS USED A MODEL BLEND. BOTTOM LINE IS
THAT TEMPS WILL NOTABLY BE ABOVE NORMAL WITH READINGS APPROACHING
90 DEGREES WHERE GREATEST SUNSHINE CAN OCCUR. MOST LIKELY AREA TO
SEE TEMPS PUSH 90 WOULD BE ACROSS THE SOUTHERN PORTION OF THE
FORECAST AREA.
.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY.
FORECAST AREA WILL BE IN THE RING OF FIRE THROUGH MUCH OF THE WEEK
AS 500 MB RIDGE SETS UP ACROSS THE EASTERN UNITED STATES. THERE
WILL BE PERIODIC CHANCES FOR THUNDERSTORMS THROUGH MUCH OF THE
WEEK. FRONTAL BOUNDARY LOCATION WILL PROBABLY MEANDER ACROSS THE
AREA AS COMPLEX OF STORMS IS EXPECTED TO PUSH BOUNDARY SOUTH AS
THE COMPLEX MOVES ACROSS THE AREA. BOUNDARY EXPECTED TO PUSH
NORTHWARD AGAIN DUE TO SOUTHERLY FLOW BEFORE NEXT COMPLEX OF
STORMS MOVES ACROSS THE REGION. THERE DOES APPEAR TO BE A TRANQUIL
PERIOD SUNDAY AS COMPLEX OF STORMS MOVES EAST OF THE AREA LATE
SATURDAY NIGHT OR EARLY SUNDAY MORNING. TEMPERATURES WILL BE WELL
ABOVE NORMAL DURING THE PERIOD...BUT HOW FAR ABOVE NORMAL WILL BE
DETERMINED BY TIMING OF THE COMPLEXES OF STORMS/CLOUDS MOVING
ACROSS THE AREA. IT APPEARS WEDNESDAY WILL BE PROBABLY THE WARMEST
DAY AS FRONT PUSHES NORTH OF THE AREA.
&&
.AVIATION...GENERALLY VFR CONDITIONS EXPECTED TODAY WITH
PRIMARILY RESIDUAL MID TO HIGH-LEVEL CLOUDS FROM OVERNIGHT
CONVECTIVE ACTIVITY. WEAK SURFACE TROUGH VERY SLOWLY DRIFTING
TOWARD THE WESTERN PORTION OF THE FORECAST AREA LATER
TODAY...ALONG WITH INCREASING INSTABLITY...MAY ASSIST IN THE
DEVELOPMENT OF SCATTERED AND POORLY ORGANIZED SHOWER AND
THUNDERSTORM ACTIVITY. CWA AND AUW STAND THE BEST CHANCE FOR
SEEING ANY CONVECTIVE ACTIVITY THAT DOES DEVELOP. AS CONVECTIVE
ACTIVITY WILL BE SCATTERED IN NATURE...DID NOT EXPLICITY MENTION
IN TAFS. MID-LEVEL CONVECTIVELY INDUCED CIRCULATION IN EXTREME WESTERN
IOWA THIS MORNING WILL APPROACH WISCONSIN OVERNIGHT AND MAY
GENERATE MORE ORGANIZED CONVECTION...BUT EXACT TIMING AND LOCATION
OF THUNDERSTORM ACTIVITY THAT MAY ACCCOMMPANY WITH THIS FEATURE IS
STILL IN QUESTION. BEST GUESS IS THAT ANY THUNDERSTORM ACTIVITY
WILL REMAIN SOUTH AND WEST OF THE FORECAST AREA UNTIL AFTER 12Z
SATURDAY.
ESB
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
621 AM CDT FRI JUN 15 2012
.SHORT TERM...THROUGH SUNDAY NIGHT
427 AM CDT FRI JUN 15 2012
THE FIRST TWO DAYS OF THIS PERIOD ARE TOUGH...WITH LITTLE FORCING
TO ANCHOR FORECAST CONFIDENCE ON. COLD FRONT BLASTING THROUGH
SATURDAY NIGHT PROVIDES A BETTER TARGET FOR CLARITY.
AT 08Z A TROUGH RAN NORTH TO SOUTH THROUGH MN WITH SOUTHEAST FLOW
BECOMING MORE UNIFORM ACROSS THE FORECAST AREA. THE
TROUGH IN MN IS A SOUTHWARD EXTENSION OF THE TROUGH FROM THE
SURFACE LOW NORTH OF LAKE WINNIPEG. THIS TROUGH IS REPRESENTED IN
THE LOW-LEVELS AS WELL...ALL PART OF THE SPOKE OF ENERGY ROTATING
EAST NEAR KINL. SOME LOWER DEW POINTS WERE NOTED ACROSS THE SOUTH
AND EAST...IN THE 50S. OVER THE PAST HOURS THE RADAR OVER THE
FORECAST AREA CONTINUES TO SHOW A DECREASING SHOWER TREND AND
CLOUD TOPS CONTINUE TO WARM. MASSIVE CONVECTIVE COMPLEX IN CENTRAL
U.S. SHOWING SIGNS OF WEAKENING...AND RADAR INDICATES A WELL-
DEFINED SPIN IN SERN NEBRASKA...THE FORECAST PROBLEM FOR TONIGHT.
00Z RAOBS WERE INFORMATIVE WITH LOW-LEVEL MOIST PLUME ALONG A
KMPX-KOMA LINE WITH DEW POINTS AT 850MB NEAR 15C..RATHER
IMPRESSIVE. SO IS THE GRADIENT SOUTHEASTWARD INTO ERN WI/ERN
IA/IL WITH DEWPOINTS NEAR 0-3C. VERY DRY TOO AT 700MB FROM KOLZ-
KDLL SOUTHEAST...YIELDING THE RAIN/TSRA EASTERN EXTENT OVERNIGHT.
NEXT WEATHER SYSTEM FOR SATURDAY MAKING ITS WAY EAST AND CLEARLY
SEEN IN THE WATER VAPOR IMAGERY ON THE SOUTHERNMOST BORDER OF
ALBERTA AND BRITISH COLUMBIA BORDER. NCEP RAP MODEL ANALYZED THIS
TIGHT/DEEP S/WV TROPOPAUSE LEVEL DOWN TO 500MB.
WITH MOISTURE PLUME TO THE NORTHWEST AND LAYING OVER THE NORTHWEST
FORECAST AREA...AND CONTINUED MOIST FLOW...AND THE TROUGH SHIFTING
EAST...HAVE DECIDED TO KEEP AN ISOLATED TSRA OVER THE AREA THIS
MORNING. SPC MUCAPE ANALYSIS SHOWS SOME WEAK INSTABILITY /1000
J/KG/ STILL IS PRESENT IN THE MOIST PLUME. BY THE AFTERNOON...THERE
IS SOME MODEL CONSENSUS THAT THE TROUGH WILL LIE FROM ABOUT KAUW
TO KCCY...AND WITH CLEARING SKIES THIS MORNING FOR THE MOST
PART...BELIEVE SBCAPE SHOULD BE NEAR 2000J/KG. THUS...HAVE KEPT
MID-RANGE RAIN CHANCES FOR CONVECTION DEVELOPING THIS AFTERNOON.
WITH MARGINAL SHEAR...CANNOT RULE OUT A SEVERE STORM OR TWO WITH
WIND OR HAIL THE THREATS. HAVE ALSO ASSESSED THE NON-SUPERCELL
TORNADO THREAT AND WHILE THE BOUNDARY IS NEARLY STATIONARY...THE
WIND FLOW IS QUITE WEAK AND THE LOW-LEVELS NOT QUITE UNSTABLE
ENOUGH TO HAVE CONFIDENCE IN THIS OUTCOME. IT COULD BE
POSSIBLE...BUT WOULD THINK FUNNELS WOULD BE SEEN WITH PARAMETER
SPACE /PER 15.06 RAP AND NAM/ NOT TOO HIGH FOR TORNADOES.
TONIGHT IS DIFFICULT. THE NCEP SUITE OF MODELS HAVE HAD A CONSENSUS
THAT A CONVECTIVELY-ENHANCED SHORTWAVE TROUGH WILL MOVE NORTHEAST
THROUGH THE FORECAST AREA OVERNIGHT...AND WE BELIEVE THIS IS THE
ROTATION IN SERN NEB AT 08Z. THE 15.00Z NAM/GFS/ECMWF/CANADIAN NRN
HEMI ALL HAVE THIS FEATURE MOVING ACROSS THE FORECAST AREA
OVERNIGHT. THIS WOULD BE DURING A TIME PERIOD OF LOWER MUCAPE
/LESS THAN 500 J/KG/ AND S/WV TROUGH WOULD TRACK EAST OF MAIN
MOIST PLUME WHICH DOESNT MOVE MUCH TODAY. OVERALL...THIS COULD BE
ANOTHER RAIN THREAT AND BRING RAIN TO MOST...BUT THE TIMING TOO IS
IN QUESTION AS TO HOW THIS WAVE GETS ABSORBED INTO THE FLOW.
CONFIDENCE IS LOW ON THIS TARGET AND TIMING...BUT DAY SHIFT SHOULD
BE ABLE TO SEE CONVECTION ENHANCING ACROSS IA THIS AFTERNOON AND
BETTER REFINE TONIGHTS FORECAST.
FINALLY ON SATURDAY THE B.C. S/WV TOUGH IMPACTS THE REGION WITH A
COLD FRONTAL PASSAGE LATE AFTERNOON AND EVENING. A FAIRLY
IMPRESSIVE MOIST POOL IS PRESENT AHEAD OF THIS FRONT AND WITH
TIMING NEAR PEAK HEATING...SBCAPE WOULD APPROACH 1500 J/KG.
HOWEVER...WIND FIELDS SUGGEST SHEAR IS WEAK WHICH SHOULD LIMIT
ORGANIZED THREATS FOR SEVERE WEATHER. WHILE FORCING IS A BIT
STRONGER...SEEMS ISOLATED SEVERE WOULD BE THE CALL. MAYBE FURTHER
NORTH WHERE MID-LEVEL FLOW IS A BIT STRONGER...WIND SHEAR WOULD
SUPPORT A SLIGHTLY BETTER STORM THREAT. POST FRONTAL AIR MASS
RACES IN SUNDAY AND HAVE REMOVED RAIN CHANCES THERE. ALSO SHIFTED
THE SATURDAY NIGHT RAIN CHANCES EAST FASTER.
SUNDAY NIGHT ALSO NEEDS TO BE WATCHED AS THE FRONTAL BOUNDARY THAT
PASSES SATURDAY NIGHT RETURNS WITH GUSTO AS A WARM FRONT. FOR
EXAMPLE...850 MB DEWPOINTS JUMP FROM LESS THAN 0C TO 14C WITHIN 6
HOURS. THESE RAPID ADVECTIONS SCREAM IMBALANCE TO ME AND CONVECTIVE
CHANCES ARE IN THE FORECAST.
.LONG TERM...MONDAY THROUGH THURSDAY NIGHT
427 AM CDT FRI JUN 15 2012
THIS PERIOD IS CHARACTERIZED BY DEEPENING BROAD LONG WAVE TROUGH
OVER THE WESTERN U.S. AND A RETURN TO HEAT IT APPEARS. MOISTURE
AND HEAT WILL BUILD IN AFTER THE WARM FRONTAL PASSAGE SUNDAY NIGHT
TO THE NORTH WITH A COLD FRONT SLOWLY STALLING OVER THE AREA FOR
TUESDAY. SOUTH OF THE FRONT IT WILL BE WARM AND HUMID WITH COOLER
RAIN CHANCES NORTH OF THE FRONT. TUESDAY APPEARS TO BE THE
CONSENSUS RAIN DAY WITH A SLOW MOVING EAST-WEST BOUNDARY OVER THE
AREA AND HIGH CAPE BUILDING TO THE SOUTH. MOST MODELS MOVE THIS
NORTHWARD ON WEDNESDAY WHICH WOULD MEAN HOT AND HUMID ALL AREAS
AND CAPPING INVERSION IN PLACE. HAVE INCREASED TEMPERATURES OVER A
CONSENSUS MODEL FORECAST ACROSS THE SOUTHERN FORECAST AREA MONDAY-
WEDNESDAY AS WE SHOULD BE WELL ABOVE GUIDANCE. WITH THE BOUNDARY
MOVING NORTH WEDNESDAY...FLOODING RAINS SHOULD NOT BE A
PROBLEM...AND TUESDAYS RAIN WILL LIKELY BE WELCOMED. DETAILS ON
EXACTLY WHERE THIS WILL OCCUR ARE STILL OF LOW CONFIDENCE...BUT A
CONSISTENT I-90 SIGNAL IS A MODEL CONSENSUS.
&&
.AVIATION...TODAY AND TONIGHT
621 AM CDT FRI JUN 15 2012
TIMING/COVERAGE OF CONVECTION REMAIN PROBLEMATIC THROUGH THIS TAF
PERIOD. QUIET VFR CONDITIONS EXPECTED THIS MORNING WITH MINIMAL
INSTABILITY OVER THE AREA AND FORCING MECHANISMS EITHER WEST OR
NORTH OF THE AREA. A WEAK SHORTWAVE NEAR KOMA EARLY THIS MORNING IS
PROGGED TO LIFT SLOWLY NORTHEAST TOWARD THE AREA FOR THIS AFTERNOON
THEN ACROSS THE AREA TONIGHT. INSTABILITY WILL INCREASE FOR THE
AFTERNOON ALONG WITH A COLD FRONT SAGGING INTO THE AREA. HOWEVER...
PLENTY OF VARIABILITY AMONG THE MODEL SOLUTIONS AND NOT A LOT OF
CONFIDENCE IN THE CONVECTIVE OUTCOME THRU TONIGHT. DID CONTINUE THE
VCTS/CB AT BOTH KRST/KLSE LATER THIS AFTERNOON/EARLY THIS EVENING
DURING PEAK HEATING/INSTABILITY. LATER SHIFTS WILL HAVE TO MONITOR
CONVECTION THRU THE DAY AS IT LIFTS NORTHEAST ACROSS IA...AND ADD
TIMING DETAILS TO TAFS WHEN A PERIOD OF SHRA/TSRA AND ANY REDUCED
CIGS/VSBYS BECOMES MORE CLEAR. CONTINUED VCSH THRU THE EVENING WITH
THE SHORTWAVE EXPECTED TO BE IN THE AREA. THIS COULD WELL BE MORE
TSRA...BUT PREFERRED NOT TO PUT EXTENSIVE HOURS OF VCTS OR TSRA IN
TAFS WHEN CONFIDENCE IS ON THE LOWER SIDE. WITH A DRY LANDSCAPE
SOUTH OF THE AREA...SFC DEW POINTS IN THE 50S AND SOUTH BOUNDARY
LAYER WINDS...CONDITIONS EXPECTED TO REMAIN VFR THIS AFTERNOON AND
TONIGHT EXCEPT IN AN SHRA/TSRA CORES. SFC WINDS TO BE ON THE LIGHT
SIDE...EXCEPT NEAR ANY CONVECTION.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
427 AM CDT FRI JUN 15 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BAUMGARDT
LONG TERM...BAUMGARDT
AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
457 AM CDT FRI JUN 15 2012
.SHORT TERM...TODAY THROUGH SATURDAY.
ANOTHER CHALLENGING FORECAST IN THE SHORT-TERM.
WATER VAPOR IMAGERY AND RAP ANALYSIS EARLY THIS MORNING SHOW
PRIMARY SHORTWAVE CONTINUING TO LIFT NORTHEAST TOWARD SOUTHERN
HUDSON BAY. ASSOCIATED CONVECTIVE ACTIVITY THAT DEVELOPED LATE
YESTERDAY OVER SE MINNESOTA AND WESTERN WISCONSIN PUSHED INTO
CENTRAL WISCONSIN OVERNIGHT AND HAS FINALLY ALL BUT DISSIPATED.
PERSISTENT STRATIFORM RAIN AREA AND ASSOCIATED EVAPORATIVE LOW-
LEVEL COOLING ALLOWED FOR WELL DEVELOPED MESO-HIGH...WITH
SUBSEQUENT SFC WAKE-LOW DEVELOPMENT ON NORTHERN PERIPHERY OF
STRATIFORM RAIN SHIELD. SOUTHERLY ISALLOBARIC WIND ACCELERATIONS
LEAD TO SURFACE WIND GUSTS TO 45 TO 50 MPH OVER PARTS OF
MARATHON...ONEIDA...WESTERN SHAWANO AND NORTHERN WOOD COUNTIES
AROUND MIDNIGHT. SOME SMALL TREES AND POWERLINES WERE BLOWN DOWN
ACROSS THIS AREA RESULTING IN SCATTERED POWER OUTAGES.
STILL SOME SCATTERED SHOWER ACTIVITY ASSOCIATED WITH REMNANT MID-
LEVEL CONVECTIVELY INDUCED CIRCULATION OVER MAINLY CENTRAL
WISCONSIN THIS MORNING. EXPECT SCATTERED MAINLY LIGHT SHOWER
ACTIVITY AND PERHAPS AN ISOLATED THUINDERSTORM TO GRADUALLY WANE
AND MOVE NORTHEAST DURING THE MORNING. ADDITIONAL SHOWER AND
THUNDERSTORM ACTIVITY FOR THE REMINADER OF THE DAY WILL MOST
LIKELY BE FOCUSED ALONG RESIDIAL CONVECTIVE OUTFLOW BOUNDARIES AND
WEAKENING FRONTAL BOUNDARY NOW ENTERING NORTHWEST WISCONSIN.
FRONTAL BOUNDARY IS FORECAST TO REMIAN QUASI-STATIONARY OR PERHAPS VERY
SLOWLY DRIFT SOUTHEAST INTO THE FORECAST AREA LATE TODAY AND
CONTINUE TO WEAKEN...THUS HARD TO PIN DOWN MOST LIKELY AREA OF
SUFFICIENT BOUNDARY LAYER CONVERGENCE TO INITIATE CONVECTION THIS
AFTERNOON. BEST GUESS WOULD BE MAINLY NORTHWEST OF THE FOX VALLEY
ACROSS CENTRAL AND NORTHERN WISCONSIN. AMOUNT OF ACTIVITY WILL
ALSO DEPEND ON THE AMOUNT OF INSOLATION AND DESTABLIZATION. BASED
ON CURRENT CLOUD TRENDS...FEEL SHOULD SEE SOME SUNSHINE TODAY TO
ALLOW MLCAPES TO CLIMB INTO THE 1000-1500 J/KG RANGE. ALTHOUGH
DEEP LAYER SHEAR WILL WEAKEN SOME DURING THE COURSE OF THE DAY AS
UPPER-LEVEL HEIGHTS TRY TO BUILD OVER THE AREA...VALUES WILL
STILL BE MARGINALLY SUPPORTIVE OF SUSTAINING STRONGER UPDRAFTS
ACROSS CENTRAL INTO NORTHERN WISCONSIN TODAY. PRIMARY THREAT WITH
ANY STRONGER STORMS THAT CAN FORM THIS AFTERNOON WOULD BE
MARGINALLY SEVERE HAIL AND GUSTY WINDS.
MAIN FORECAST PROBLEM OVERNIGHT TONIGHT INTO SATURDAY WILL BE WHAT
HAPPENS WITH CONVECTIVELY INDUCED CIRCULATION NOW LOCATED OVER
EASTERN NEBRASKA. CURRENT RADAR TRENDS SUGGEST CIRCULATION IS
SLOWELY DRIFTING NORTHWARD INTO EXTREME WESTERN IOWA. MODELS
SUGGEST THIS FEATURE WILL GRADUALLY BE LIFTED NORTHEAST TOWARD THE
WESTERN GREAT LAKES AS PRIMARY SHORTWAVE MOVES EASTWARD ACROSS THE
US-CANADA BORDER TO NEAR LAKE WINNEPEG BY 12Z SATURDAY.
ECMWF...GEM AND NAM SUGGEST A SLOWER AND MORE NORTHERN
TRACK...TAKING THE MCV MORE TO THE WEST OF THE FORECAST AREA. GFS
CONTINUES TO BE THE MOST AGRESSIVE WITH A MORE NORTHEAST TRACK
INTO THE FORECAST AREA AFTER MIDNIGHT. BASED ON CURRENT RADAR
TRENDS AND THAT THE GFS SEEMS TO BE THE OUTLIER...FEEL MORE
FOCUSED CONVECTIVE ACTIVITY WITH THIS FEATURE WILL NOT AFFECT THE
FORECAST AREA UNTIL AFTER 12Z SATURDAY...THUS WAS MORE
CONSERVATIVE ON POPS OVERNIGHT. AS PRIMARY SHORTWAVE CONTINUES
ITS TRACK EASTWARD TOWARD THE WESTERN GREAT LAKES ON SATURDAY
AFTERNOON...IT WILL DRAW MORE UNSTABLE AIRMASS INTO THE FORECAST
AREA INCREASING THE CHANCE FOR MORE WIDESPREAD CONVECTION
ESPECIALLY WEST OF THE FOX VALLEY. THIS ACTIVITY SHOULD BEGIN TO MOVE
INTO THE EASTERN PART OF THE FORECAST AREA TOWARD EVENING ASSUMING
IT CAN OVERCOME DRIER AIR STILL IN PLACE OVER LOWER MICHIGAN AND
EASTERN WISCONSIN.
MAX TEMPS TODAY AND SATURDAY WILL AGAIN BE TRICKY DEPENDING ON
AMOUNT OF CLOUD COVER...THUS USED A MODEL BLEND. BOTTOM LINE IS
THAT TEMPS WILL NOTABLY BE ABOVE NORMAL WITH READINGS APPROACHING
90 DEGREES WHERE GREATEST SUNSHINE CAN OCCUR. MOST LIKELY AREA TO
SEE TEMPS PUSH 90 WOULD BE ACROSS THE SOUTHERN PORTION OF THE
FORECAST AREA.
.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY.
FORECAST AREA WILL BE IN THE RING OF FIRE THROUGH MUCH OF THE WEEK
AS 500 MB RIDGE SETS UP ACROSS THE EASTERN UNITED STATES. THERE
WILL BE PERIODIC CHANCES FOR THUNDERSTORMS THROUGH MUCH OF THE
WEEK. FRONTAL BOUNDARY LOCATION WILL PROBABLY MEANDER ACROSS THE
AREA AS COMPLEX OF STORMS IS EXPECTED TO PUSH BOUNDARY SOUTH AS
THE COMPLEX MOVES ACROSS THE AREA. BOUNDARY EXPECTED TO PUSH
NORTHWARD AGAIN DUE TO SOUTHERLY FLOW BEFORE NEXT COMPLEX OF
STORMS MOVES ACROSS THE REGION. THERE DOES APPEAR TO BE A TRANQUIL
PERIOD SUNDAY AS COMPLEX OF STORMS MOVES EAST OF THE AREA LATE
SATURDAY NIGHT OR EARLY SUNDAY MORNING. TEMPERATURES WILL BE WELL
ABOVE NORMAL DURING THE PERIOD...BUT HOW FAR ABOVE NORMAL WILL BE
DETERMINED BY TIMING OF THE COMPLEXES OF STORMS/CLOUDS MOVING
ACROSS THE AREA. IT APPEARS WEDNESDAY WILL BE PROBABLY THE WARMEST
DAY AS FRONT PUSHES NORTH OF THE AREA.
&&
.AVIATION...WARMER AND MORE HUMID AIR IS TRYING TO MOVE NORTHWARD
INTO CENTRAL AND NORTHCENTRAL WISCONSIN. IT IS RISING OVER THE
COOLER AIR NEAR THE SURFACE AND PRODUCING SHOWERS AND
THUNDERSTORMS. THIS ACTIVITY IS EXPECTED MAINLY SOUTH OF A MERRILL
(RRL) TO OSHKOSH (OSH) LINE BUT THERE COULD BE SHOWERS FURTHER TO
THE NORTH. CIGS WILL GENERALLY BE IN THE VFR RANGE EVEN WHERE IT
IS RAINING. LOW LEVEL WIND SHEAR POSSIBLE ACROSS THE REGION WITH
SOUTH WINDS OF 30 TO 40 KTS AT 1000 FT AGL.
RDM
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
ESB/ECKBERG
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
427 AM CDT FRI JUN 15 2012
.SHORT TERM...THROUGH SUNDAY NIGHT
427 AM CDT FRI JUN 15 2012
THE FIRST TWO DAYS OF THIS PERIOD ARE TOUGH...WITH LITTLE FORCING
TO ANCHOR FORECAST CONFIDENCE ON. COLD FRONT BLASTING THROUGH
SATURDAY NIGHT PROVIDES A BETTER TARGET FOR CLARITY.
AT 08Z A TROUGH RAN NORTH TO SOUTH THROUGH MN WITH SOUTHEAST FLOW
BECOMING MORE UNIFORM ACROSS THE FORECAST AREA. THE
TROUGH IN MN IS A SOUTHWARD EXTENTION OF THE TROUGH FROM THE
SURFACE LOW NORTH OF LAKE WINNIPEG. THIS TROUGH IS REPRESENTED IN
THE LOW-LEVELS AS WELL...ALL PART OF THE SPOKE OF ENERGY ROTATING
EAST NEAR KINL. SOME LOWER DEW POINTS WERE NOTED ACROSS THE SOUTH
AND EAST...IN THE 50S. OVER THE PAST HOURS THE RADAR OVER THE
FORECAST AREA CONTINUES TO SHOW A DECREASING SHOWER TREND AND
CLOUD TOPS CONTINUE TO WARM. MASSIVE CONVECTIVE COMPLEX IN CENTRAL
U.S. SHOWING SIGNS OF WEAKENING...AND RADAR INDICATES A WELL-
DEFINED SPIN IN SERN NEBRASKA...THE FORECAST PROBLEM FOR TONIGHT.
00Z RAOBS WERE INFORMATIVE WITH LOW-LEVEL MOIST PLUME ALONG A
KMPX-KOMA LINE WITH DEW POINTS AT 850MB NEAR 15C..RATHER
IMPRESSIVE. SO IS THE GRADIENT SOUTHEASTWARD INTO ERN WI/ERN
IA/IL WITH DEWPOINTS NEAR 0-3C. VERY DRY TOO AT 700MB FROM KOEL-
KDLL SOUTHEAST...YIELDING THE RAIN/TSRA EASTERN EXTENT OVERNIGHT.
NEXT WEATHER SYSTEM FOR SATURDAY MAKING ITS WAY EAST AND CLEARLY
SEEN IN THE WATER VAPOR IMAGERY ON THE SOUTHERNMOST BORDER OF
ALBERTA AND BRITISH COLUMBIA BORDER. NCEP RAP MODEL ANALYZED THIS
TIGHT/DEEP S/WV TROPOPAUSE LEVEL DOWN TO 500MB.
WITH MOISTURE PLUME TO THE NORTHWEST AND LAYING OVER THE NORTHWEST
FORECAST AREA...AND CONTINUED MOIST FLOW...AND THE TROUGH SHIFTING
EAST...HAVE DECIDED TO KEEP AN ISOLATED TSRA OVER THE AREA THIS
MORNING. SPC MUCAPE ANALYSIS SHOWS SOME WEAK INSTABILITY /1000
J/KG/ STILL IS PRESENT IN THE MOIST PLUME. BY THE AFTERNOON...THERE
IS SOME MODEL CONSENSUS THAT THE TROUGH WILL LIE FROM ABOUT KAUW
TO KCCY...AND WITH CLEARING SKIES THIS MORNING FOR THE MOST
PART...BELIEVE SBCAPE SHOULD BE NEAR 2000J/KG. THUS...HAVE KEPT
MID-RANGE RAIN CHANCES FOR CONVECTION DEVELOPING THIS AFTERNOON.
WITH MARGINAL SHEAR...CANNOT RULE OUT A SEVERE STORM OR TWO WITH
WIND OR HAIL THE THREATS. HAVE ALSO ASSESSED THE NON-SUPERCELL
TORNADO THREAT AND WHILE THE BOUNDARY IS NEARLY STATIONARY...THE
WIND FLOW IS QUITE WEAK AND THE LOW-LEVELS NOT QUITE UNSTABLE
ENOUGH TO HAVE CONFIDENCE IN THIS OUTCOME. IT COULD BE
POSSIBLE...BUT WOULD THINK FUNNELS WOULD BE SEEN WITH PARAMETER
SPACE /PER 15.06 RAP AND NAM/ NOT TOO HIGH FOR TORNADOES.
TONIGHT IS DIFFICULT. THE NCEP SUITE OF MODELS HAVE HAD A CONSENSUS
THAT A CONVECTIVELY-ENHANCED SHORTWAVE TROUGH WILL MOVE NORTHEAST
THROUGH THE FORECAST AREA OVERNIGHT...AND WE BELIEVE THIS IS THE
ROTATION IN SERN NEB AT 08Z. THE 15.00Z NAM/GFS/ECMWF/CANADIAN NRN
HEMI ALL HAVE THIS FEATURE MOVING ACROSS THE FORECAST AREA
OVERNIGHT. THIS WOULD BE DURING A TIME PERIOD OF LOWER MUCAPE
/LESS THAN 500 J/KG/ AND S/WV TROUGH WOULD TRACK EAST OF MAIN
MOIST PLUME WHICH DOESNT MOVE MUCH TODAY. OVERALL...THIS COULD BE
ANOTHER RAIN THREAT AND BRING RAIN TO MOST...BUT THE TIMING TOO IS
IN QUESTION AS TO HOW THIS WAVE GETS ABSORBED INTO THE FLOW.
CONFIDENCE IS LOW ON THIS TARGET AND TIMING...BUT DAY SHIFT SHOULD
BE ABLE TO SEE CONVECTION ENHANCING ACROSS IA THIS AFTERNOON AND
BETTER REFINE TONIGHTS FORECAST.
FINALLY ON SATURDAY THE B.C. S/WV TOUGH IMPACTS THE REGION WITH A
COLD FRONTAL PASSAGE LATE AFTERNOON AND EVENING. A FAIRLY
IMPRESSIVE MOIST POOL IS PRESENT AHEAD OF THIS FRONT AND WITH
TIMING NEAR PEAK HEATING...SBCAPE WOULD APPROACH 1500 J/KG.
HOWEVER...WIND FIELDS SUGGEST SHEAR IS WEAK WHICH SHOULD LIMIT
ORGANIZED THREATS FOR SEVERE WEATHER. WHILE FORCING IS A BIT
STRONGER...SEEMS ISOLATED SEVERE WOULD BE THE CALL. MAYBE FURTHER
NORTH WHERE MID-LEVEL FLOW IS A BIT STRONGER...WIND SHEAR WOULD
SUPPORT A SLIGHTLY BETTER STORM THREAT. POST FRONTAL AIR MASS
RACES IN SUNDAY AND HAVE REMOVED RAIN CHANCES THERE. ALSO SHIFTED
THE SATURDAY NIGHT RAIN CHANCES EAST FASTER.
SUNDAY NIGHT ALSO NEEDS TO BE WATCHED AS THE FRONTAL BOUNDARY THAT
PASSES SATURDAY NIGHT RETURNS WITH GUSTO AS A WARM FRONT. FOR
EXAMPLE...850 MB DEWPOINTS JUMP FROM LESS THAN 0C TO 14C WITHIN 6
HOURS. THESE RAPID ADVECTIONS SCREAM IMBALANCE TO ME AND CONVECTIVE
CHANCES ARE IN THE FORECAST.
.LONG TERM...MONDAY THROUGH THURSDAY NIGHT
427 AM CDT FRI JUN 15 2012
THIS PERIOD IS CHARACTERIZED BY DEEPENING BROAD LONG WAVE TROUGH
OVER THE WESTERN U.S. AND A RETURN TO HEAT IT APPEARS. MOISTURE
AND HEAT WILL BUILD IN AFTER THE WARM FRONTAL PASSAGE SUNDAY NIGHT
TO THE NORTH WITH A COLD FRONT SLOWLY STALLING OVER THE AREA FOR
TUESDAY. SOUTH OF THE FRONT IT WILL BE WARM AND HUMID WITH COOLER
RAIN CHANCES NORTH OF THE FRONT. TUESDAY APPEARS TO BE THE
CONSENSUS RAIN DAY WITH A SLOW MOVING EAST-WEST BOUNDARY OVER THE
AREA AND HIGH CAPE BUILDING TO THE SOUTH. MOST MODELS MOVE THIS
NORTHWARD ON WEDNESDAY WHICH WOULD MEAN HOT AND HUMID ALL AREAS
AND CAPPING INVERSION IN PLACE. HAVE INCREASED TEMPERATURES OVER A
CONSENSUS MODEL FORECAST ACROSS THE SOUTHERN FORECAST AREA MONDAY-
WEDNESDAY AS WE SHOULD BE WELL ABOVE GUIDANCE. WITH THE BOUNDARY
MOVING NORTH WEDNESDAY...FLOODING RAINS SHOULD NOT BE A
PROBLEM...AND TUESDAYS RAIN WILL LIKELY BE WELCOMED. DETAILS ON
EXACTLY WHERE THIS WILL OCCUR ARE STILL OF LOW CONFIDENCE...BUT A
CONSISTENT I-90 SIGNAL IS A MODEL CONSENSUS.
&&
.AVIATION...
1115 PM CDT THU JUN 14 2012
MIXED SIGNALS IN THE MESO MODELS OVERNIGHT AS SOME SUGGEST THE
CURRENT SHRA/TS WILL PERSIST OVERNIGHT...WHILE OTHERS POINT TO A
DIMINISHING/ENDING TREND. PCPN IS FIRING IN THE VICINITY OF A
FRONTAL BOUNDARY OVERNIGHT...AS LOW LEVEL MOISTURE
TRANSPORT/INSTABILITY CONTINUES TO FEED IT. AS THE INSTABILITY
WEAKENS EXPECT SOME DECREASE IN INTENSITY AND AREAL EXTENT...BUT
WITH THE BOUNDARY IN PLACE AND A PERSISTENT STREAM OF LOW LEVEL
MOISTURE...SCATTERED -SHRA/TS SEEMS MORE PROBABLE. BETTER CHANCES
WOULD BE AT KRST WHICH IS CLOSER TO THE BOUNDARY. WILL LIKELY STICK
WITH VCSH UNLESS TRENDS SHOW DEFINITE PERIODS OF -SHRA/TS.
THE COLD FRONT LOOKS TO WAVER NORTHEAST-SOUTHWEST ACROSS THE REGION
ON FRIDAY...AND WILL LIKELY SERVE AS THE FOCUS FOR MORE SHRA/TS.
GREATER INSTABILITY IN THE AFTERNOON/EARLY EVENING WOULD FAVOR THIS
TIME FRAME FOR CONVECTION. CONFIDENCE NOT TOO HIGH ON TIMING THOUGH.
EXPECT THAT TAFS WILL NEED AMENDMENTS WHEN TIMING FOR PCPN THREATS
BECOMES MORE CLEAR.
OVERALL...VFR CONDITIONS ARE EXPECTED OUTSIDE OF THE ANY
THUNDERSTORM THAT WOULD IMPACT KRST/KLSE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
427 AM CDT FRI JUN 15 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BAUMGARDT
LONG TERM...BAUMGARDT
AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
356 AM CDT SUN JUN 17 2012
.MESOSCALE DISCUSSION...
947 PM CDT
HAVE CLEARED ABOUT THE NORTHERN HALF OF THE CWA FROM SEVERE
THUNDERSTORM WATCH. OBJECTIVE ANALYSIS AS WELL AS RADAR/SATELLITE
IMAGERY SUGGEST THAT SUFFICIENT CINH IS IN PLACE TO PREVENT SEVERE
THUNDERSTORM DEVELOPMENT NORTH OF I-80. HAVE OPTED TO LEAVE COOK
COUNTY IN THE WATCH SINCE SOME STRONGER CELLS IN NORTHWEST WILL
COUNTY WILL BE MOVING THROUGH IN THE NEXT 30-60 MINS. FARTHER
SOUTH OVER SOUTHERN PORTIONS OF THE CWA THE SEVERE THREAT ALSO
APPEARS TO BE DIMINISHING AS PREVIOUS STORMS AND OUTFLOW HAVE
LIKELY RESULTED IN MORE STABLE CONDITIONS. WILL HANG ON TO THE
SEVERE THUNDERSTORM WATCH FOR THESE AREAS THOUGH AS THERE IS STILL
SOME STRONG STORMS WITHIN THE LINE AND IT IS NOT OUT OF THE
QUESTION THAT THERE COULD BE SOME RE-INTENSIFICATION. IF CLOUD
TOPS CONTINUE TO COOL AND STORMS CONTINUE TO WEAKEN THEN THE
REMAINDER OF THE WATCH MAY BE ABLE TO BE CANCELLED EARLY.
IZZI
&&
.DISCUSSION...
330 PM CDT
A FEW AREAS OF CONCERN OVER THE COMING DAYS. THE FIRST WILL BE THE
POTENTIALLY SEVERE WEATHER THIS EVENING...FOLLOWED BY VERY HOT
WEATHER OPENING UP THE WORK WEEK. FOLLOWING THE SHOWERS AND
THUNDERSTORMS TONIGHT...THE NEXT CHANCE FOR PRECIPITATION WILL NOT
BE UNTIL LATER IN THE WEEK.
IN THE SHORT TERM...GOING THREAT FOR MORE OF AN EXPANDED
COVERAGE OF SHOWERS AND THUNDERSTORMS WILL BE ON THE INCREASE.
SYNOPTIC COLD FRONT WELL TO THE WEST AND ACROSS THE PLAINS AND
TIED TO A LOW LIFTING ACROSS CANADA IS SLOWLY SHIFTING TO THE
EAST. THIS FRONT WILL CONTINUE TO MOVE TOWARDS THE REGION
TONIGHT...BUT WEAKEN CONSIDERABLY BY THE TIME IT REACHES EASTERN
IOWA TONIGHT.
FOR THE IMMEDIATE AFTERNOON...SOUTHWESTERLY FLOW HAS ALLOWED A
RATHER LARGE SURGE OF MOISTURE TO BE TRANSPORTED ACROSS THE REGION.
OUTSIDE OF AREAS THAT SAW RAIN THIS MORNING...DEWPOINTS HAVE JUMPED
FROM AROUND 50 DEGREES TO THE MIDDLE AND UPPER 60S. FORECAST
SOUNDINGS NOT INDICATING MUCH DRY AIR TO IMPEDE THE CLIMB...AND
HAVE NUDGED DEWPOINTS UP ACROSS THE AREA. THE HIGHEST AXIS OF
INSTABILITY IS GENERALLY ANTICIPATED TO REMAIN SOUTH OF THE
AREA...AND CLOSER TO THE IOWA/ILLINOIS/MISSOURI JUNCTION...BUT
MUCAPE VALUES IN THE 1500 TO 2000 J/KG RANGE ARE STILL LIKELY
ACROSS THE EAST THIS AFTERNOON AND UP TO THE WI BORDER. OVERALL
SHEAR IS LOW...AND TIED CLOSER TO THE WAVE LIFTING ACROSS
WISCONSIN. GENERALLY EXPECTING THE SMALL...BUT EFFICIENT RAIN
PRODUCING SHOWERS AND THUNDER TO CONTINUE TO BUBBLE THIS AFTERNOON.
THE GREATEST CHANCES THROUGH AFTERNOON DO APPEAR TO BE EAST OF THE
I57 CORRIDOR...AND WEST OF I39.
THE PRIMARY FOCUS LATER THIS AFTERNOON AND INTO THE EVENING WILL BE
TIED TO A STRONG WAVE THAT IS SLIDING ACROSS THE MISSOURI AND IOWA
BORDER THIS AFTERNOON. PRESENTLY...SHOWER AND THUNDERSTORM CLUSTERS
ARE INCREASING IN OVERALL COVERAGE WITH AND AHEAD OF THIS FEATURE. THE
HIGHEST INSTABILITY AXIS IS WEST AND ACROSS THE MO/IA/IL BORDER
REGION...WITH RAP ANALYZED VALUES NEARING THE 3-4000 MARK. SHEAR
WILL INCREASE AS THE WAVE APPROACHES...AND THE CLUSTER OF STORMS
WILL INCREASE IN COVERAGE AS THEY SHIFT EAST...AND INTO A
SUPPORTIVE ENVIRONMENT. FORECAST SOUNDINGS AND MORNING RAOBS
SHOW A CONSIDERABLE INCREASE OF MOISTURE...WITH PWAT VALUES
JUMPING 2/3 TO 3/4 OF AN INCH ABOVE THEIR MORNING VALUES /AND
PEAKING AROUND THE 1.9 INCH RANGE. AS WAS SEEN EARLIER IN THE
DAY...IT DOES NOT TAKE MUCH FOR THESE STORMS TO PUT OUT A LOT OF
PRECIPITATION. THE LATEST HRRR HAS BEEN A DECENT PROXY FOR
COVERAGE AND TIMING...AND ANTICIPATE COVERAGE TO INCREASE FOR
ROCKFORD BEYOND THE 6P HOUR AND A FEW HOURS BEYOND FOR CHICAGO.
HEAVY RAIN IS THE BIGGEST THREAT WITH THESE STORMS...BUT SOME
POCKETS MAY CONTAIN SUB TO MARGINALLY SEVERE HAIL AND STRONG
WINDS ARE POSSIBLE...THOUGH DIURNALLY BY THE TIME THEY REACH THE
MAJORITY OF THE CWA...IT WILL BE GETTING INTO AN UNFAVORABLE TIME.
THE RAIN WILL BE WELCOME FOR MANY AREAS...BUT OVERALL DROUGHT
BUSTING ONES ARE NOT A LIKELIHOOD.
LONG TERM...THE JET ENGINE WILL TURN ON. THE COLD FRONT THAT IS
MARCHING EAST ACROSS THE MISSISSIPPI VALLEY TODAY WILL BASICALLY
WASH OUT AND ONLY DROP DEWPOINTS DOWN INTO THE LOWER 60S TO UPPER
50S...AND KEEP HIGH TEMPERATURES INTO THE 80S TOMORROW. BIG H8
THERMAL RIDGE WILL SLOWLY SHIFT EAST FROM THE PLAINS AND CLOSE TO
THE REGION...WARMING THE AREA BACK UP MONDAY. ENDED UP BUMPING UP HIGHS
FOR BOTH MONDAY AND TUESDAY TO BE INTO THE UPPER 90 RANGE /AND CAN
SEE A POSSIBLE 100 MARK SOMEWHERE ACROSS THE REGION/ IN THAT TIME.
NOT ONLY WILL IT BE HOT ON MONDAY...IT WILL BE INCREDIBLY WINDY.
FORECAST SOUNDINGS SHOW MIXED LAYER WINDS BREACHING THE 30KT
RANGE. THE POTENTIAL FOR CRITICAL FIRE WEATHER CONDITIONS WILL BE
ELEVATED...BUT SPECIFICS WILL BE FOLLOWED UP IN THE FIRE WEATHER
DISCUSSIONS THROUGH THE WEEKEND. THE 90S WILL CONTINUE THROUGH
WEDNESDAY...BEFORE A FRONT MOVES THROUGH THURSDAY AND COOLS OFF
THE AREA WITH THE NEXT CHANCE FOR SHOWERS AND STORMS.
SHEA
&&
.FIRE WEATHER...
515 PM CDT
HOT AND WINDY CONDITIONS MAY RESULT IN CRITICAL AND DANGEROUS
FIRE WEATHER CONDITIONS ON MONDAY.
FOR THE REMAINDER OF THIS AFTERNOON AND THIS EVENING...INCREASING
DEWPOINTS ACROSS THE AREA WILL LIMIT MINIMUM RELATIVE HUMIDITY
VALUES TO 35 TO 40 PERCENT AS TEMPERATURES TOP OUT IN THE LOWER
90S. WINDS WILL OUT OF THE SOUTHWEST AT 10 TO 15 MPH...GUSTING
TO AROUND 20 MPH.
SCATTERED SHOWERS AND THUNDERSTORMS WILL BRING WETTING RAIN TO
SOME LOCATIONS THROUGH EARLY THIS EVENING. THERE IS THE POTENTIAL
FOR ADDITIONAL THUNDERSTORMS THROUGH LATE THIS EVENING WHICH MAY
BRING SOME ADDITIONAL WETTING RAIN...AND SOME THUNDERSTORMS MAY
EVEN BRING SOME LOCALLY HEAVY RAINFALL.
WHILE RED FLAG CRITERIA WILL NOT BE REACHED TODAY...THE RECENT
VERY DRY CONDITIONS COMBINED WITH HIGH TEMPERATURES...MODESTLY
LOW DEW POINTS AND MODERATELY STRONG WINDS WILL RESULT IN ELEVATED
WILDFIRE DANGER.
A WEAK...COLD FRONT WILL MOVE INTO THE AREA TONIGHT AND EARLY
SUNDAY MORNING...BRINGING SLIGHTLY COOLER AIR...WITH HIGHS IN THE
MID AND UPPER 80S.
MUCH WARMER AIR WILL RETURN MONDAY WITH SOUTHWEST WINDS GUSTING AS
HIGH AS 40 MPH. SOME QUESTION REMAINS AS TO HOW LOW DEWPOINTS MAY
MAY DROP MONDAY AFTERNOON IF DRIER AIR ALOFT MIXES DOWN TO THE
SURFACE. CURRENTLY...EXPECT THAT HIGH TEMPERATURES WILL BE IN THE
MIDDLE 90S. EVEN DEWPOINTS IN THE LOWER 60S WILL CAUSE RELATIVE
HUMIDITY VALUES TO DROP CLOSE TO 30 PERCENT OVER MUCH OF THE AREA
AND DEWPOINTS IN THE UPPER 50S WILL BRING RELATIVE HUMIDITY LEVELS
IN RED FLAG CRITERIA RANGE.
ANOTHER WILD CARD IS HOW RAINFALL OCCURRING THIS AFTERNOON AND HOW
MUCH ADDITIONAL RAINFALL THAT MAY OCCUR LATER THIS EVENING WILL
AFFECT FUEL MOISTURE LEVELS AS WELL AS SOIL MOISTURE LEVELS. THE
GREATER THE AMOUNT OF WIDESPREAD WETTING RAIN TODAY AND TONIGHT...
THE MORE LIKELY THAT RELATIVE HUMIDITY LEVELS WILL BE ABOVE RED
FLAG CRITERIA.
HOWEVER...EVEN IF RELATIVE HUMIDITY LEVELS ARE ABOVE RED FLAG
CRITERIA...THE EXPECTED TEMPERATURE AND WIND CONDITIONS COMBINED
WITH THE RECENT DRY CONDITIONS WILL ELEVATE THE FIRE DANGER...
ESPECIALLY FOR ANY AREAS THAT DO NOT RECEIVE MUCH WETTING RAINFALL
THIS EVENING AND TONIGHT AS FUEL MOISTURE WILL REMAIN QUITE LOW.
WHILE HIGH TEMPERATURES ARE EXPECTED TO REMAIN IN THE LOWER AND
MID 90S FOR TUESDAY AND WEDNESDAY...DEW POINTS ARE EXPECTED TO
SIGNIFICANTLY INCREASE...PREVENTING MINIMUM RELATIVE HUMIDITY
VALUES FROM DROPPING TO CRITICAL LEVELS.
ANOTHER COLD FRONT WILL MOVE INTO THE AREA THURSDAY...BRINGING
ANOTHER CHANCE OF SHOWERS AND THUNDERSTORMS. DAYTIME TEMPERATURES
WILL BE SOMEWHAT LOWER THURSDAY...AND SIGNIFICANTLY LOWER FRIDAY
WITH HIGHS IN THE UPPER 70S TO MID 80S.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* OCCASIONAL MVFR CIGS POSSIBLE THROUGH 13Z WITH BRIEF IFR CIGS
POSSIBLE.
* TEMPORARY MVFR VISIBILITY IN FOG AT TIMES.
* VARIABLE WINDS AT TIMES THROUGH DAYBREAK.
//DISCUSSION...UPDATED 06Z...
COMPLEX OF THUNDERSTORMS HAS DIMINISHED SIGNIFICANTLY IN
INTENSITY...WITH TRAILING AREA OF STRATIFORM RAIN GRADUALLY MOVING
EASTWARD. THIS CONTINUES TO KEEP THE LOW-LEVEL AIR SOMEWHAT
MOIST...AND THERE HAVE BEEN PATCHES OF MVFR CIGS...WITH EVEN IFR
CONDITIONS IN FAR SE IA. EXPECT THAT TEMPORARY MVFR CIGS WILL
CONTINUE AT TIMES PRIOR TO 12Z...EVEN AFTER THE RAIN ENDS.
VISIBILITY MAY EVEN DROP INTO THE MVFR CATEGORY BRIEFLY AS
TEMPERATURE/DEW POINT SPREADS ARE FAIRLY LOW. CLIMATOLOGY FOR THIS
TIME OF YEAR POINTS TO ANY MVFR CONDITIONS OUTSIDE OF RAIN BEING
BRIEF AND SEE NO REASON THAT WOULD NOT BE THE CASE THIS TIME.
WINDS WILL SETTLE INTO A WESTERLY DIRECTION IN THE FEW HOURS
FOLLOWING DAYBREAK. THESE WILL BACK TO THE SOUTH LATE IN THE DAY
AS THE SURFACE RIDGE AXIS MOVES PAST. SOUTHWEST WINDS IN THE 500
FT TO 2000 FT LAYER WILL INCREASE TO 25 TO 30 KT LATE SUNDAY
NIGHT.
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* MEDIUM CONFIDENCE IN TEMPORARY MVFR CIGS THROUGH DAYBREAK...WITH
LOW CONFIDENCE IN TIMING OF IFR CIGS...THOUGH DURATION IS LIKELY
TO BE BRIEF IF/WHEN THEY OCCUR.
* MEDIUM CONFIDENCE IN WIND TRENDS THROUGH 12Z. HIGH CONFIDENCE
AFTER.
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...VFR. SSW WINDS G35KT. VERY HOT/HIGH DENSITY ALTITUDE.
TUESDAY AND WEDNESDAY...VFR. VERY HOT/HIGH DENSITY ALTITUDE.
THURSDAY AND FRIDAY...CHC TSRA...OTHERWISE VFR.
MTF/IZZI
&&
.MARINE...
300 AM CDT
AN ACTIVE MARINE PATTERN...ESPECIALLY FOR JUNE...WILL CONTINUE
DURING THE EARLY PART OF THIS WEEK. A COOL FRONT WILL CLEAR THE
LAKE BY MID MORNING...BRIEFLY SHIFTING WINDS TO THE WEST LATE THIS
MORNING ACROSS THE SOUTHERN HALF OF THE LAKE OR SO. WINDS WILL
TURN BACK SOUTHERLY DURING THE AFTERNOON DUE TO INFLUENCE OF
ANOTHER LOW PRESSURE DEVELOPING ACROSS THE UPPER MIDWEST. THIS
DEEP LOW WILL TRACK NORTHEAST LATE TONIGHT INTO MONDAY LEADING TO
AN INCREASE IN WINDS. THE LOW PRESSURE PATH IS FAVORABLE FOR
STRONG SUSTAINED WINDS...EVEN WITHIN THE STABLE MARINE
LAYER...ESPECIALLY ACROSS THE NORTHERN TWO-THIRDS OF THE LAKE. IN
ADDITION...A COMPLEX OF THUNDERSTORMS MAY BE CROSSING THE NORTHERN
AND CENTRAL PARTS OF THE LAKE ON MONDAY MORNING INTO THE EARLY TO
MID AFTERNOON. SUCH A COMPLEX COULD HAVE STRONG WESTERLY WINDS
WITH IT. THE GENERALLY PREVAILING SOUTHERLY WINDS WILL CONTINUE
ON TUESDAY AND WEDNESDAY AS MULTIPLE LOW PRESSURE SYSTEMS TAKE THE
PATH OF THEIR PREDECESSORS FROM THE UPPER MIDWEST INTO ONTARIO.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-
LMZ745...10 AM MONDAY TO 10 PM MONDAY.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
302 AM CDT SUN JUN 17 2012
.MESOSCALE DISCUSSION...
947 PM CDT
HAVE CLEARED ABOUT THE NORTHERN HALF OF THE CWA FROM SEVERE
THUNDERSTORM WATCH. OBJECTIVE ANALYSIS AS WELL AS RADAR/SATELLITE
IMAGERY SUGGEST THAT SUFFICIENT CINH IS IN PLACE TO PREVENT SEVERE
THUNDERSTORM DEVELOPMENT NORTH OF I-80. HAVE OPTED TO LEAVE COOK
COUNTY IN THE WATCH SINCE SOME STRONGER CELLS IN NORTHWEST WILL
COUNTY WILL BE MOVING THROUGH IN THE NEXT 30-60 MINS. FARTHER
SOUTH OVER SOUTHERN PORTIONS OF THE CWA THE SEVERE THREAT ALSO
APPEARS TO BE DIMINISHING AS PREVIOUS STORMS AND OUTFLOW HAVE
LIKELY RESULTED IN MORE STABLE CONDITIONS. WILL HANG ON TO THE
SEVERE THUNDERSTORM WATCH FOR THESE AREAS THOUGH AS THERE IS STILL
SOME STRONG STORMS WITHIN THE LINE AND IT IS NOT OUT OF THE
QUESTION THAT THERE COULD BE SOME RE-INTENSIFICATION. IF CLOUD
TOPS CONTINUE TO COOL AND STORMS CONTINUE TO WEAKEN THEN THE
REMAINDER OF THE WATCH MAY BE ABLE TO BE CANCELLED EARLY.
IZZI
&&
.DISCUSSION...
330 PM CDT
A FEW AREAS OF CONCERN OVER THE COMING DAYS. THE FIRST WILL BE THE
POTENTIALLY SEVERE WEATHER THIS EVENING...FOLLOWED BY VERY HOT
WEATHER OPENING UP THE WORK WEEK. FOLLOWING THE SHOWERS AND
THUNDERSTORMS TONIGHT...THE NEXT CHANCE FOR PRECIPITATION WILL NOT
BE UNTIL LATER IN THE WEEK.
IN THE SHORT TERM...GOING THREAT FOR MORE OF AN EXPANDED
COVERAGE OF SHOWERS AND THUNDERSTORMS WILL BE ON THE INCREASE.
SYNOPTIC COLD FRONT WELL TO THE WEST AND ACROSS THE PLAINS AND
TIED TO A LOW LIFTING ACROSS CANADA IS SLOWLY SHIFTING TO THE
EAST. THIS FRONT WILL CONTINUE TO MOVE TOWARDS THE REGION
TONIGHT...BUT WEAKEN CONSIDERABLY BY THE TIME IT REACHES EASTERN
IOWA TONIGHT.
FOR THE IMMEDIATE AFTERNOON...SOUTHWESTERLY FLOW HAS ALLOWED A
RATHER LARGE SURGE OF MOISTURE TO BE TRANSPORTED ACROSS THE REGION.
OUTSIDE OF AREAS THAT SAW RAIN THIS MORNING...DEWPOINTS HAVE JUMPED
FROM AROUND 50 DEGREES TO THE MIDDLE AND UPPER 60S. FORECAST
SOUNDINGS NOT INDICATING MUCH DRY AIR TO IMPEDE THE CLIMB...AND
HAVE NUDGED DEWPOINTS UP ACROSS THE AREA. THE HIGHEST AXIS OF
INSTABILITY IS GENERALLY ANTICIPATED TO REMAIN SOUTH OF THE
AREA...AND CLOSER TO THE IOWA/ILLINOIS/MISSOURI JUNCTION...BUT
MUCAPE VALUES IN THE 1500 TO 2000 J/KG RANGE ARE STILL LIKELY
ACROSS THE EAST THIS AFTERNOON AND UP TO THE WI BORDER. OVERALL
SHEAR IS LOW...AND TIED CLOSER TO THE WAVE LIFTING ACROSS
WISCONSIN. GENERALLY EXPECTING THE SMALL...BUT EFFICIENT RAIN
PRODUCING SHOWERS AND THUNDER TO CONTINUE TO BUBBLE THIS AFTERNOON.
THE GREATEST CHANCES THROUGH AFTERNOON DO APPEAR TO BE EAST OF THE
I57 CORRIDOR...AND WEST OF I39.
THE PRIMARY FOCUS LATER THIS AFTERNOON AND INTO THE EVENING WILL BE
TIED TO A STRONG WAVE THAT IS SLIDING ACROSS THE MISSOURI AND IOWA
BORDER THIS AFTERNOON. PRESENTLY...SHOWER AND THUNDERSTORM CLUSTERS
ARE INCREASING IN OVERALL COVERAGE WITH AND AHEAD OF THIS FEATURE. THE
HIGHEST INSTABILITY AXIS IS WEST AND ACROSS THE MO/IA/IL BORDER
REGION...WITH RAP ANALYZED VALUES NEARING THE 3-4000 MARK. SHEAR
WILL INCREASE AS THE WAVE APPROACHES...AND THE CLUSTER OF STORMS
WILL INCREASE IN COVERAGE AS THEY SHIFT EAST...AND INTO A
SUPPORTIVE ENVIRONMENT. FORECAST SOUNDINGS AND MORNING RAOBS
SHOW A CONSIDERABLE INCREASE OF MOISTURE...WITH PWAT VALUES
JUMPING 2/3 TO 3/4 OF AN INCH ABOVE THEIR MORNING VALUES /AND
PEAKING AROUND THE 1.9 INCH RANGE. AS WAS SEEN EARLIER IN THE
DAY...IT DOES NOT TAKE MUCH FOR THESE STORMS TO PUT OUT A LOT OF
PRECIPITATION. THE LATEST HRRR HAS BEEN A DECENT PROXY FOR
COVERAGE AND TIMING...AND ANTICIPATE COVERAGE TO INCREASE FOR
ROCKFORD BEYOND THE 6P HOUR AND A FEW HOURS BEYOND FOR CHICAGO.
HEAVY RAIN IS THE BIGGEST THREAT WITH THESE STORMS...BUT SOME
POCKETS MAY CONTAIN SUB TO MARGINALLY SEVERE HAIL AND STRONG
WINDS ARE POSSIBLE...THOUGH DIURNALLY BY THE TIME THEY REACH THE
MAJORITY OF THE CWA...IT WILL BE GETTING INTO AN UNFAVORABLE TIME.
THE RAIN WILL BE WELCOME FOR MANY AREAS...BUT OVERALL DROUGHT
BUSTING ONES ARE NOT A LIKELIHOOD.
LONG TERM...THE JET ENGINE WILL TURN ON. THE COLD FRONT THAT IS
MARCHING EAST ACROSS THE MISSISSIPPI VALLEY TODAY WILL BASICALLY
WASH OUT AND ONLY DROP DEWPOINTS DOWN INTO THE LOWER 60S TO UPPER
50S...AND KEEP HIGH TEMPERATURES INTO THE 80S TOMORROW. BIG H8
THERMAL RIDGE WILL SLOWLY SHIFT EAST FROM THE PLAINS AND CLOSE TO
THE REGION...WARMING THE AREA BACK UP MONDAY. ENDED UP BUMPING UP HIGHS
FOR BOTH MONDAY AND TUESDAY TO BE INTO THE UPPER 90 RANGE /AND CAN
SEE A POSSIBLE 100 MARK SOMEWHERE ACROSS THE REGION/ IN THAT TIME.
NOT ONLY WILL IT BE HOT ON MONDAY...IT WILL BE INCREDIBLY WINDY.
FORECAST SOUNDINGS SHOW MIXED LAYER WINDS BREACHING THE 30KT
RANGE. THE POTENTIAL FOR CRITICAL FIRE WEATHER CONDITIONS WILL BE
ELEVATED...BUT SPECIFICS WILL BE FOLLOWED UP IN THE FIRE WEATHER
DISCUSSIONS THROUGH THE WEEKEND. THE 90S WILL CONTINUE THROUGH
WEDNESDAY...BEFORE A FRONT MOVES THROUGH THURSDAY AND COOLS OFF
THE AREA WITH THE NEXT CHANCE FOR SHOWERS AND STORMS.
SHEA
&&
.FIRE WEATHER...
515 PM CDT
HOT AND WINDY CONDITIONS MAY RESULT IN CRITICAL AND DANGEROUS
FIRE WEATHER CONDITIONS ON MONDAY.
FOR THE REMAINDER OF THIS AFTERNOON AND THIS EVENING...INCREASING
DEWPOINTS ACROSS THE AREA WILL LIMIT MINIMUM RELATIVE HUMIDITY
VALUES TO 35 TO 40 PERCENT AS TEMPERATURES TOP OUT IN THE LOWER
90S. WINDS WILL OUT OF THE SOUTHWEST AT 10 TO 15 MPH...GUSTING
TO AROUND 20 MPH.
SCATTERED SHOWERS AND THUNDERSTORMS WILL BRING WETTING RAIN TO
SOME LOCATIONS THROUGH EARLY THIS EVENING. THERE IS THE POTENTIAL
FOR ADDITIONAL THUNDERSTORMS THROUGH LATE THIS EVENING WHICH MAY
BRING SOME ADDITIONAL WETTING RAIN...AND SOME THUNDERSTORMS MAY
EVEN BRING SOME LOCALLY HEAVY RAINFALL.
WHILE RED FLAG CRITERIA WILL NOT BE REACHED TODAY...THE RECENT
VERY DRY CONDITIONS COMBINED WITH HIGH TEMPERATURES...MODESTLY
LOW DEW POINTS AND MODERATELY STRONG WINDS WILL RESULT IN ELEVATED
WILDFIRE DANGER.
A WEAK...COLD FRONT WILL MOVE INTO THE AREA TONIGHT AND EARLY
SUNDAY MORNING...BRINGING SLIGHTLY COOLER AIR...WITH HIGHS IN THE
MID AND UPPER 80S.
MUCH WARMER AIR WILL RETURN MONDAY WITH SOUTHWEST WINDS GUSTING AS
HIGH AS 40 MPH. SOME QUESTION REMAINS AS TO HOW LOW DEWPOINTS MAY
MAY DROP MONDAY AFTERNOON IF DRIER AIR ALOFT MIXES DOWN TO THE
SURFACE. CURRENTLY...EXPECT THAT HIGH TEMPERATURES WILL BE IN THE
MIDDLE 90S. EVEN DEWPOINTS IN THE LOWER 60S WILL CAUSE RELATIVE
HUMIDITY VALUES TO DROP CLOSE TO 30 PERCENT OVER MUCH OF THE AREA
AND DEWPOINTS IN THE UPPER 50S WILL BRING RELATIVE HUMIDITY LEVELS
IN RED FLAG CRITERIA RANGE.
ANOTHER WILD CARD IS HOW RAINFALL OCCURRING THIS AFTERNOON AND HOW
MUCH ADDITIONAL RAINFALL THAT MAY OCCUR LATER THIS EVENING WILL
AFFECT FUEL MOISTURE LEVELS AS WELL AS SOIL MOISTURE LEVELS. THE
GREATER THE AMOUNT OF WIDESPREAD WETTING RAIN TODAY AND TONIGHT...
THE MORE LIKELY THAT RELATIVE HUMIDITY LEVELS WILL BE ABOVE RED
FLAG CRITERIA.
HOWEVER...EVEN IF RELATIVE HUMIDITY LEVELS ARE ABOVE RED FLAG
CRITERIA...THE EXPECTED TEMPERATURE AND WIND CONDITIONS COMBINED
WITH THE RECENT DRY CONDITIONS WILL ELEVATE THE FIRE DANGER...
ESPECIALLY FOR ANY AREAS THAT DO NOT RECEIVE MUCH WETTING RAINFALL
THIS EVENING AND TONIGHT AS FUEL MOISTURE WILL REMAIN QUITE LOW.
WHILE HIGH TEMPERATURES ARE EXPECTED TO REMAIN IN THE LOWER AND
MID 90S FOR TUESDAY AND WEDNESDAY...DEW POINTS ARE EXPECTED TO
SIGNIFICANTLY INCREASE...PREVENTING MINIMUM RELATIVE HUMIDITY
VALUES FROM DROPPING TO CRITICAL LEVELS.
ANOTHER COLD FRONT WILL MOVE INTO THE AREA THURSDAY...BRINGING
ANOTHER CHANCE OF SHOWERS AND THUNDERSTORMS. DAYTIME TEMPERATURES
WILL BE SOMEWHAT LOWER THURSDAY...AND SIGNIFICANTLY LOWER FRIDAY
WITH HIGHS IN THE UPPER 70S TO MID 80S.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* RAIN THROUGH EARLY OVERNIGHT WITH PATCHY MVFR VISIBILITIES.
* OCCASIONAL MVFR CIGS POSSIBLE THROUGH 12Z.
* VARIABLE WINDS AT TIMES THROUGH DAYBREAK.
//DISCUSSION...UPDATED 06Z...
COMPLEX OF THUNDERSTORMS HAS DIMINISHED SIGNIFICANTLY IN
INTENSITY...WITH TRAILING AREA OF STRATIFORM RAIN GRADUALLY MOVING
EASTWARD. THIS CONTINUES TO KEEP THE LOW-LEVEL AIR SOMEWHAT
MOIST...AND THERE HAVE BEEN PATCHES OF MVFR CIGS...WITH EVEN IFR
CONDITIONS IN FAR SE IA. EXPECT THAT TEMPORARY MVFR CIGS WILL
CONTINUE AT TIMES PRIOR TO 12Z...EVEN AFTER THE RAIN ENDS.
VISIBILITY MAY EVEN DROP INTO THE MVFR CATEGORY BRIEFLY AS
TEMPERATURE/DEW POINT SPREADS ARE FAIRLY LOW. CLIMATOLOGY FOR THIS
TIME OF YEAR POINTS TO ANY MVFR CONDITIONS OUTSIDE OF RAIN BEING
BRIEF AND SEE NO REASON THAT WOULD NOT BE THE CASE THIS TIME.
WINDS WILL SETTLE INTO A WESTERLY DIRECTION IN THE FEW HOURS
FOLLOWING DAYBREAK. THESE WILL BACK TO THE SOUTH LATE IN THE DAY
AS THE SURFACE RIDGE AXIS MOVES PAST. SOUTHWEST WINDS IN THE 500
FT TO 2000 FT LAYER WILL INCREASE TO 25 TO 30 KT LATE SUNDAY
NIGHT.
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE IN RAIN ENDING TIME.
* MEDIUM CONFIDENCE IN TEMPORARY MVFR CIGS THROUGH DAYBREAK.
* MEDIUM CONFIDENCE IN WIND TRENDS THROUGH DAYBREAK. HIGH
CONFIDENCE AFTER.
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...VFR. SSW WINDS G35KT. VERY HOT/HIGH DENSITY ALTITUDE.
TUESDAY AND WEDNESDAY...VFR. VERY HOT/HIGH DENSITY ALTITUDE.
THURSDAY AND FRIDAY...CHC TSRA...OTHERWISE VFR.
MTF/IZZI
&&
.MARINE...
300 AM CDT
AN ACTIVE MARINE PATTERN...ESPECIALLY FOR JUNE...WILL CONTINUE
DURING THE EARLY PART OF THIS WEEK. A COOL FRONT WILL CLEAR THE
LAKE BY MID MORNING...BRIEFLY SHIFTING WINDS TO THE WEST LATE THIS
MORNING ACROSS THE SOUTHERN HALF OF THE LAKE OR SO. WINDS WILL
TURN BACK SOUTHERLY DURING THE AFTERNOON DUE TO INFLUENCE OF
ANOTHER LOW PRESSURE DEVELOPING ACROSS THE UPPER MIDWEST. THIS
DEEP LOW WILL TRACK NORTHEAST LATE TONIGHT INTO MONDAY LEADING TO
AN INCREASE IN WINDS. THE LOW PRESSURE PATH IS FAVORABLE FOR
STRONG SUSTAINED WINDS...EVEN WITHIN THE STABLE MARINE
LAYER...ESPECIALLY ACROSS THE NORTHERN TWO-THIRDS OF THE LAKE. IN
ADDITION...A COMPLEX OF THUNDERSTORMS MAY BE CROSSING THE NORTHERN
AND CENTRAL PARTS OF THE LAKE ON MONDAY MORNING INTO THE EARLY TO
MID AFTERNOON. SUCH A COMPLEX COULD HAVE STRONG WESTERLY WINDS
WITH IT. THE GENERALLY PREVAILING SOUTHERLY WINDS WILL CONTINUE
ON TUESDAY AND WEDNESDAY AS MULTIPLE LOW PRESSURE SYSTEMS TAKE THE
PATH OF THEIR PREDECESSORS FROM THE UPPER MIDWEST INTO ONTARIO.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1247 AM CDT SUN JUN 17 2012
.MESOSCALE DISCUSSION...
947 PM CDT
HAVE CLEARED ABOUT THE NORTHERN HALF OF THE CWA FROM SEVERE
THUNDERSTORM WATCH. OBJECTIVE ANALYSIS AS WELL AS RADAR/SATELLITE
IMAGERY SUGGEST THAT SUFFICIENT CINH IS IN PLACE TO PREVENT SEVERE
THUNDERSTORM DEVELOPMENT NORTH OF I-80. HAVE OPTED TO LEAVE COOK
COUNTY IN THE WATCH SINCE SOME STRONGER CELLS IN NORTHWEST WILL
COUNTY WILL BE MOVING THROUGH IN THE NEXT 30-60 MINS. FARTHER
SOUTH OVER SOUTHERN PORTIONS OF THE CWA THE SEVERE THREAT ALSO
APPEARS TO BE DIMINISHING AS PREVIOUS STORMS AND OUTFLOW HAVE
LIKELY RESULTED IN MORE STABLE CONDITIONS. WILL HANG ON TO THE
SEVERE THUNDERSTORM WATCH FOR THESE AREAS THOUGH AS THERE IS STILL
SOME STRONG STORMS WITHIN THE LINE AND IT IS NOT OUT OF THE
QUESTION THAT THERE COULD BE SOME RE-INTENSIFICATION. IF CLOUD
TOPS CONTINUE TO COOL AND STORMS CONTINUE TO WEAKEN THEN THE
REMAINDER OF THE WATCH MAY BE ABLE TO BE CANCELLED EARLY.
IZZI
&&
.DISCUSSION...
330 PM CDT
A FEW AREAS OF CONCERN OVER THE COMING DAYS. THE FIRST WILL BE THE
POTENTIALLY SEVERE WEATHER THIS EVENING...FOLLOWED BY VERY HOT
WEATHER OPENING UP THE WORK WEEK. FOLLOWING THE SHOWERS AND
THUNDERSTORMS TONIGHT...THE NEXT CHANCE FOR PRECIPITATION WILL NOT
BE UNTIL LATER IN THE WEEK.
IN THE SHORT TERM...GOING THREAT FOR MORE OF AN EXPANDED
COVERAGE OF SHOWERS AND THUNDERSTORMS WILL BE ON THE INCREASE.
SYNOPTIC COLD FRONT WELL TO THE WEST AND ACROSS THE PLAINS AND
TIED TO A LOW LIFTING ACROSS CANADA IS SLOWLY SHIFTING TO THE
EAST. THIS FRONT WILL CONTINUE TO MOVE TOWARDS THE REGION
TONIGHT...BUT WEAKEN CONSIDERABLY BY THE TIME IT REACHES EASTERN
IOWA TONIGHT.
FOR THE IMMEDIATE AFTERNOON...SOUTHWESTERLY FLOW HAS ALLOWED A
RATHER LARGE SURGE OF MOISTURE TO BE TRANSPORTED ACROSS THE REGION.
OUTSIDE OF AREAS THAT SAW RAIN THIS MORNING...DEWPOINTS HAVE JUMPED
FROM AROUND 50 DEGREES TO THE MIDDLE AND UPPER 60S. FORECAST
SOUNDINGS NOT INDICATING MUCH DRY AIR TO IMPEDE THE CLIMB...AND
HAVE NUDGED DEWPOINTS UP ACROSS THE AREA. THE HIGHEST AXIS OF
INSTABILITY IS GENERALLY ANTICIPATED TO REMAIN SOUTH OF THE
AREA...AND CLOSER TO THE IOWA/ILLINOIS/MISSOURI JUNCTION...BUT
MUCAPE VALUES IN THE 1500 TO 2000 J/KG RANGE ARE STILL LIKELY
ACROSS THE EAST THIS AFTERNOON AND UP TO THE WI BORDER. OVERALL
SHEAR IS LOW...AND TIED CLOSER TO THE WAVE LIFTING ACROSS
WISCONSIN. GENERALLY EXPECTING THE SMALL...BUT EFFICIENT RAIN
PRODUCING SHOWERS AND THUNDER TO CONTINUE TO BUBBLE THIS AFTERNOON.
THE GREATEST CHANCES THROUGH AFTERNOON DO APPEAR TO BE EAST OF THE
I57 CORRIDOR...AND WEST OF I39.
THE PRIMARY FOCUS LATER THIS AFTERNOON AND INTO THE EVENING WILL BE
TIED TO A STRONG WAVE THAT IS SLIDING ACROSS THE MISSOURI AND IOWA
BORDER THIS AFTERNOON. PRESENTLY...SHOWER AND THUNDERSTORM CLUSTERS
ARE INCREASING IN OVERALL COVERAGE WITH AND AHEAD OF THIS FEATURE. THE
HIGHEST INSTABILITY AXIS IS WEST AND ACROSS THE MO/IA/IL BORDER
REGION...WITH RAP ANALYZED VALUES NEARING THE 3-4000 MARK. SHEAR
WILL INCREASE AS THE WAVE APPROACHES...AND THE CLUSTER OF STORMS
WILL INCREASE IN COVERAGE AS THEY SHIFT EAST...AND INTO A
SUPPORTIVE ENVIRONMENT. FORECAST SOUNDINGS AND MORNING RAOBS
SHOW A CONSIDERABLE INCREASE OF MOISTURE...WITH PWAT VALUES
JUMPING 2/3 TO 3/4 OF AN INCH ABOVE THEIR MORNING VALUES /AND
PEAKING AROUND THE 1.9 INCH RANGE. AS WAS SEEN EARLIER IN THE
DAY...IT DOES NOT TAKE MUCH FOR THESE STORMS TO PUT OUT A LOT OF
PRECIPITATION. THE LATEST HRRR HAS BEEN A DECENT PROXY FOR
COVERAGE AND TIMING...AND ANTICIPATE COVERAGE TO INCREASE FOR
ROCKFORD BEYOND THE 6P HOUR AND A FEW HOURS BEYOND FOR CHICAGO.
HEAVY RAIN IS THE BIGGEST THREAT WITH THESE STORMS...BUT SOME
POCKETS MAY CONTAIN SUB TO MARGINALLY SEVERE HAIL AND STRONG
WINDS ARE POSSIBLE...THOUGH DIURNALLY BY THE TIME THEY REACH THE
MAJORITY OF THE CWA...IT WILL BE GETTING INTO AN UNFAVORABLE TIME.
THE RAIN WILL BE WELCOME FOR MANY AREAS...BUT OVERALL DROUGHT
BUSTING ONES ARE NOT A LIKELIHOOD.
LONG TERM...THE JET ENGINE WILL TURN ON. THE COLD FRONT THAT IS
MARCHING EAST ACROSS THE MISSISSIPPI VALLEY TODAY WILL BASICALLY
WASH OUT AND ONLY DROP DEWPOINTS DOWN INTO THE LOWER 60S TO UPPER
50S...AND KEEP HIGH TEMPERATURES INTO THE 80S TOMORROW. BIG H8
THERMAL RIDGE WILL SLOWLY SHIFT EAST FROM THE PLAINS AND CLOSE TO
THE REGION...WARMING THE AREA BACK UP MONDAY. ENDED UP BUMPING UP HIGHS
FOR BOTH MONDAY AND TUESDAY TO BE INTO THE UPPER 90 RANGE /AND CAN
SEE A POSSIBLE 100 MARK SOMEWHERE ACROSS THE REGION/ IN THAT TIME.
NOT ONLY WILL IT BE HOT ON MONDAY...IT WILL BE INCREDIBLY WINDY.
FORECAST SOUNDINGS SHOW MIXED LAYER WINDS BREACHING THE 30KT
RANGE. THE POTENTIAL FOR CRITICAL FIRE WEATHER CONDITIONS WILL BE
ELEVATED...BUT SPECIFICS WILL BE FOLLOWED UP IN THE FIRE WEATHER
DISCUSSIONS THROUGH THE WEEKEND. THE 90S WILL CONTINUE THROUGH
WEDNESDAY...BEFORE A FRONT MOVES THROUGH THURSDAY AND COOLS OFF
THE AREA WITH THE NEXT CHANCE FOR SHOWERS AND STORMS.
SHEA
&&
.FIRE WEATHER...
515 PM CDT
HOT AND WINDY CONDITIONS MAY RESULT IN CRITICAL AND DANGEROUS
FIRE WEATHER CONDITIONS ON MONDAY.
FOR THE REMAINDER OF THIS AFTERNOON AND THIS EVENING...INCREASING
DEWPOINTS ACROSS THE AREA WILL LIMIT MINIMUM RELATIVE HUMIDITY
VALUES TO 35 TO 40 PERCENT AS TEMPERATURES TOP OUT IN THE LOWER
90S. WINDS WILL OUT OF THE SOUTHWEST AT 10 TO 15 MPH...GUSTING
TO AROUND 20 MPH.
SCATTERED SHOWERS AND THUNDERSTORMS WILL BRING WETTING RAIN TO
SOME LOCATIONS THROUGH EARLY THIS EVENING. THERE IS THE POTENTIAL
FOR ADDITIONAL THUNDERSTORMS THROUGH LATE THIS EVENING WHICH MAY
BRING SOME ADDITIONAL WETTING RAIN...AND SOME THUNDERSTORMS MAY
EVEN BRING SOME LOCALLY HEAVY RAINFALL.
WHILE RED FLAG CRITERIA WILL NOT BE REACHED TODAY...THE RECENT
VERY DRY CONDITIONS COMBINED WITH HIGH TEMPERATURES...MODESTLY
LOW DEW POINTS AND MODERATELY STRONG WINDS WILL RESULT IN ELEVATED
WILDFIRE DANGER.
A WEAK...COLD FRONT WILL MOVE INTO THE AREA TONIGHT AND EARLY
SUNDAY MORNING...BRINGING SLIGHTLY COOLER AIR...WITH HIGHS IN THE
MID AND UPPER 80S.
MUCH WARMER AIR WILL RETURN MONDAY WITH SOUTHWEST WINDS GUSTING AS
HIGH AS 40 MPH. SOME QUESTION REMAINS AS TO HOW LOW DEWPOINTS MAY
MAY DROP MONDAY AFTERNOON IF DRIER AIR ALOFT MIXES DOWN TO THE
SURFACE. CURRENTLY...EXPECT THAT HIGH TEMPERATURES WILL BE IN THE
MIDDLE 90S. EVEN DEWPOINTS IN THE LOWER 60S WILL CAUSE RELATIVE
HUMIDITY VALUES TO DROP CLOSE TO 30 PERCENT OVER MUCH OF THE AREA
AND DEWPOINTS IN THE UPPER 50S WILL BRING RELATIVE HUMIDITY LEVELS
IN RED FLAG CRITERIA RANGE.
ANOTHER WILD CARD IS HOW RAINFALL OCCURRING THIS AFTERNOON AND HOW
MUCH ADDITIONAL RAINFALL THAT MAY OCCUR LATER THIS EVENING WILL
AFFECT FUEL MOISTURE LEVELS AS WELL AS SOIL MOISTURE LEVELS. THE
GREATER THE AMOUNT OF WIDESPREAD WETTING RAIN TODAY AND TONIGHT...
THE MORE LIKELY THAT RELATIVE HUMIDITY LEVELS WILL BE ABOVE RED
FLAG CRITERIA.
HOWEVER...EVEN IF RELATIVE HUMIDITY LEVELS ARE ABOVE RED FLAG
CRITERIA...THE EXPECTED TEMPERATURE AND WIND CONDITIONS COMBINED
WITH THE RECENT DRY CONDITIONS WILL ELEVATE THE FIRE DANGER...
ESPECIALLY FOR ANY AREAS THAT DO NOT RECEIVE MUCH WETTING RAINFALL
THIS EVENING AND TONIGHT AS FUEL MOISTURE WILL REMAIN QUITE LOW.
WHILE HIGH TEMPERATURES ARE EXPECTED TO REMAIN IN THE LOWER AND
MID 90S FOR TUESDAY AND WEDNESDAY...DEW POINTS ARE EXPECTED TO
SIGNIFICANTLY INCREASE...PREVENTING MINIMUM RELATIVE HUMIDITY
VALUES FROM DROPPING TO CRITICAL LEVELS.
ANOTHER COLD FRONT WILL MOVE INTO THE AREA THURSDAY...BRINGING
ANOTHER CHANCE OF SHOWERS AND THUNDERSTORMS. DAYTIME TEMPERATURES
WILL BE SOMEWHAT LOWER THURSDAY...AND SIGNIFICANTLY LOWER FRIDAY
WITH HIGHS IN THE UPPER 70S TO MID 80S.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* RAIN THROUGH EARLY OVERNIGHT WITH PATCHY MVFR VISIBILITIES.
* OCCASIONAL MVFR CIGS POSSIBLE THROUGH 12Z.
* VARIABLE WINDS AT TIMES THROUGH DAYBREAK.
//DISCUSSION...UPDATED 06Z...
COMPLEX OF THUNDERSTORMS HAS DIMINISHED SIGNIFICANTLY IN
INTENSITY...WITH TRAILING AREA OF STRATIFORM RAIN GRADUALLY MOVING
EASTWARD. THIS CONTINUES TO KEEP THE LOW-LEVEL AIR SOMEWHAT
MOIST...AND THERE HAVE BEEN PATCHES OF MVFR CIGS...WITH EVEN IFR
CONDITIONS IN FAR SE IA. EXPECT THAT TEMPORARY MVFR CIGS WILL
CONTINUE AT TIMES PRIOR TO 12Z...EVEN AFTER THE RAIN ENDS.
VISIBILITY MAY EVEN DROP INTO THE MVFR CATEGORY BRIEFLY AS
TEMPERATURE/DEW POINT SPREADS ARE FAIRLY LOW. CLIMATOLOGY FOR THIS
TIME OF YEAR POINTS TO ANY MVFR CONDITIONS OUTSIDE OF RAIN BEING
BRIEF AND SEE NO REASON THAT WOULD NOT BE THE CASE THIS TIME.
WINDS WILL SETTLE INTO A WESTERLY DIRECTION IN THE FEW HOURS
FOLLOWING DAYBREAK. THESE WILL BACK TO THE SOUTH LATE IN THE DAY
AS THE SURFACE RIDGE AXIS MOVES PAST. SOUTHWEST WINDS IN THE 500
FT TO 2000 FT LAYER WILL INCREASE TO 25 TO 30 KT LATE SUNDAY
NIGHT.
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE IN RAIN ENDING TIME.
* MEDIUM CONFIDENCE IN TEMPORARY MVFR CIGS THROUGH DAYBREAK.
* MEDIUM CONFIDENCE IN WIND TRENDS THROUGH DAYBREAK. HIGH
CONFIDENCE AFTER.
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...VFR. SSW WINDS G35KT. VERY HOT/HIGH DENSITY ALTITUDE.
TUESDAY AND WEDNESDAY...VFR. VERY HOT/HIGH DENSITY ALTITUDE.
THURSDAY AND FRIDAY...CHC TSRA...OTHERWISE VFR.
MTF/IZZI
&&
.MARINE...
156 PM CDT
AN ACTIVE WEATHER PATTERN ACROSS THE NORTHERN UNITED STATES WILL
PRODUCE SEVERAL LOW PRESSURE SYSTEMS INTO NEXT WEEK...EACH OF THESE
LOWS ARE EXPECTED TO TRACK FROM THE PLAINS ACROSS THE UPPER
MISSISSIPPI VALLEY AND INTO ONTARIO. THESE SYSTEMS WILL PRODUCE
PERIODS OF STRONGER SOUTHERLY WINDS ACROSS THE LAKE. HOWEVER...THE MAIN
CONCERNS ACROSS THE LAKE WILL BE ON MONDAY AS A STRONG PRESSURE
GRADIENT SETS UP. THIS WILL LIKELY SUPPORT A PERIOD OF 30 KT
SOUTHERLY WINDS ON MONDAY INTO MONDAY NIGHT. THERE IS ALSO A
POTENTIAL FOR SOME GALE FORCE GUSTS...ESPECIALLY ACROSS THE
ILLINOIS AND INDIANA NEAR SHORES. STRONG GUSTS UP AROUND 35 KT ARE
POSSIBLE OVER THE LAND AREAS OF NORTHERN ILLINOIS...AND DUE TO
THE EXPECTED OFFSHORE COMPONENT TO THE FLOW...THESE WIND GUSTS
COULD EASILY AFFECT THE NEAR SHORE WATERS.
SOUTH TO SOUTHWESTERLY WINDS SHOULD CONTINUE AROUND 15 TO 25 KT
THROUGH THE MIDDLE OF NEXT WEEK AS WE REMAIN TO THE EAST OF LOW
PRESSURE ACROSS THE PLAINS AND UPPER MIDWEST.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 2 AM SUNDAY.
&&
$$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
420 AM EDT SUN JUN 17 2012
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 203 AM EDT SUN JUN 17 2012
A WEAK FRONT WILL CROSS INDIANA AND THEN MOVE OFF TO THE NORTHEAST
TODAY. FOR MONDAY THROUGH WEDNESDAY EXPECT THE HOOSIER STATE TO BE
WEDGED BETWEEN HIGH PRESSURE ALONG THE EAST COAST AND A COLD FRONT
OVER THE PLAINS. THE FRONT SHOULD FINALLY CROSS INDIANA
THURSDAY...THEN BE FOLLOWED BY HIGH PRESSURE THAT WILL LINGER
THROUGH THE WEEK.
&&
.NEAR TERM /TODAY/...
ISSUED AT 203 AM EDT SUN JUN 17 2012
POPS ARE THE PROBLEM OF THE DAY.
STORMS TO OUR WEST ARE DYING AS THEY SLOWLY MOVE EAST...BUT ARE
APT TO LEAVE BOUNDARY SOMEWHERE OVER US TODAY. NONE OF THE
SYNOPTIC MODELS ARE LIKELY TO HANDLE THIS WELL. HOWEVER...THEY
ALL HAVE A WEAK WAVE CROSSING ALOFT TODAY WHICH WILL LIKELY IGNITE
CONVECTION WHEREVER THE BOUNDARY IS.
TO REALLY GET A GOOD HANDLE ON THE SITUATION...WE MAY HAVE TO WAIT
UNTIL THE RUC FORECASTS START EXTENDING WELL INTO THE DAY PERIOD.
FOR NOW I WILL BASICALLY USE A MET MAV ENSEMBLE TO GET THE BEST
OF EACH. HOWEVER...I WILL AT LEAST BE CHANCE AS OPPOSED TO SLIGHT
CHANCE EVERYWHERE. WILL SAY LIKELY IN NORTHWEST. WHILE
PRECIPITATION NOW THERE MAY DIE BY 12Z...NEED TO ACCOUNT FOR IT
SOMEWHAT WITH THIS PACKAGE.
WITH SO MUCH UNCERTAINTY ABOUT CLOUDS AND PRECIPITATION...WILL
TAKE CONSENSUS OF GUIDANCE TEMPERATURES...AGAIN TO CAPTURE
ENSEMBLE EFFECT.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
ISSUED AT 203 AM EDT SUN JUN 17 2012
PROBLEM IS RAIN CHANCES THROUGH MONDAY. AFTER THAT MODELS CONCUR
RIDGE BUILDING OVER AREA SHUTTING PRECIPITATION DOWN.
WE COULD GET STORMS EARLY TONIGHT FROM STUFF THAT FIRES DURING DAY
AND SURVIVES INTO EVENING. AFTER THAT SOME STUFF COULD STILL DEVELOP
IN WARM HUMID AIR UNTIL RIDGE REALLY BUILDS BY TUESDAY EVENING.
DONT SEE HOW I CAN BEAT THE GUIDANCE THIS FAR IN THE FUTURE. WILL
COMBINE MAV AND MET HOPING FOR BEST OF BOTH.
ON TEMPERATURES USING THE MET. MAV HAS NOT BEEN DOING WELL
IN UNSEASONABLE WARMTH LATELY.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
ISSUED AT 245 AM EDT SUN JUN 17 2012
STRONG UPPER LEVEL RIDGE WILL STILL BE IN CONTROL OVER THE AREA
EARLY IN THE LONG TERM PERIOD...HOWEVER GUIDANCE DEPICTS AN UPPER
LEVEL WAVE AND ASSOCIATED COLD FRONT HELPING TO ERODE THE RIDGE
SOMEWHAT AND SHUTTLE IT TO THE EAST THURSDAY AND FRIDAY. THIS
MERITS AT LEAST SOME LOW THUNDERSTORM CHANCES DURING THIS
TIME...AND INITIALIZATION HANDLED THIS RELATIVELY WELL...WITH SOME
TWEAKS.
SURFACE HIGH SETTLES ACROSS THE AREA IN THE WAKE OF THE
FRONT...AND GUIDANCE DEPICTS BROAD RIDGING ALOFT STRENGTHENING TO
OUR WEST OVER THE WEEKEND. THAT SAID...MODELS HINT AT THE
POTENTIAL FOR THUNDERSTORM ACTIVITY...PERHAPS IN THE FORM OF ONE
OR MORE MCS/S...DURING PORTIONS OF THE WEEKEND IN THE NORTHWEST
FLOW. THIS...AND THE SLIGHT CHANCE POPS INTIALIZATION GAVE TO
HANDLE IT...APPEAR REASONABLE...ESPECIALLY AS WE ARE ENTERING THE
TIME OF YEAR WHEN ORGANIZED RIDGE RIDING CONVECTION IN NORTHWEST FLOW
BECOMES RELATIVELY COMMON. DUE TO SIGNIFICANT UNCERTAINTY...CANNOT
JUSTIFY MORE THAN SLIGHT CHANCE POPS FOR PORTIONS OF THE REGION
AT THE MOMENT.
REMAINDER OF BLEND WAS REASONABLE...WITH A FEW MINOR TWEAKS TO
MAX/MIN TEMPS AFTER CONSULTING 850 TEMP PROGS. ASIDE FROM WHAT
LOOKS TO BE BRIEF RETURN TO NEAR NORMAL TEMPS FRIDAY AND
SATURDAY...90 DEGREE HEAT WILL NOT BE GOING ANYWHERE ANYTIME SOON
FOR LENGTHY PERIODS.
&&
.AVIATION /DISCUSSION FOR THE 170600Z TAF ISSUANCE/...
ISSUED AT 420 AM EDT SUN JUN 17 2012
REMOVED THUNDER MENTION FOR THE REMAINDER OF THE NIGHT FROM ALL
TAFS...AS THUNDERSTORMS HAVE LARGELY DISSIPATED THAT MIGHT HAVE
THREATENED THE TAF SITES. ADDITIONAL CONVECTION MAY BE POSSIBLE
LATER TODAY...AND WILL ADDRESS THAT IN THE 12Z PACKAGE. PREVIOUS
DISCUSSION FOLLOWS.
ISSUED AT 1240 AM EDT SUN JUN 17 2012
LINE OF THUNDERSTORMS FROM NEAR KCHI TO KSTL WILL CONTINUE INTO OUR
AREA OVERNIGHT AND WEAKEN AS AN UPPER TROUGH CONTINUES EAST ACROSS
THE GREAT LAKES. RADAR LOOPS INDICATE STORM MAY PUSH INTO THE KLAF
AND KHUF AREA AROUND TAF ISSUANCE AND WILL MENTION PERIOD OF
TEMPO TSRA AT THOSE SITES. IT MAY REACH KIND AND KBMG AFTER
10Z...BUT MUCH OF THE LINE MAY BE BREAKING UP BY THEN SO WILL ONLY
MENTION VCTS AT KBMG AND KIND.
WHATS LEFT OF THUNDERSTORMS WILL CLEAR ALL AREAS BY 15Z. THERE WILL
PROBABLY BE SOME REDEVELOPMENT ACROSS THE SOUTHEAST HALF OF INDIANA
SUNDAY AFTERNOON AS DAYTIME HEATING TAKES HOLD. THE NAM MODEL
INDICATES MOST OF THIS REDEVELOPMENT WILL OCCUR EAST AND SOUTHEAST
OF KIND AND KBMG TAFS AND WITH LOW CONFIDENCE OF MORE THUNDER
AFFECTING ANY TAFS WILL LEAVE OUT MENTION FOR NOW. MODELS INDICATE
DRIER AIR WILL BE SPREADING IN FROM THE NORTHWEST SUNDAY AFTERNOON
AND EVENING. OVERALL TAFS WILL BE MOSTLY VFR THROUGH THE PERIOD.
WINDS WILL BE 8 KNOTS OR LESS OVERNIGHT AND WEST TO SOUTHWEST AT
10-12 KNOTS SUNDAY WITH LIGHT SOUTHWEST WINDS SUNDAY EVENING.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...JK
NEAR TERM...JK
SHORT TERM...JK
LONG TERM....NIELD
AVIATION...JH/NIELD
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
245 AM EDT SUN JUN 17 2012
.UPDATE...
THE LONG TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 203 AM EDT SUN JUN 17 2012
A WEAK FRONT WILL CROSS INDIANA AND THEN MOVE OFF TO THE NORTHEAST
TODAY. FOR MONDAY THROUGH WEDNESDAY EXPECT THE HOOSIER STATE TO BE
WEDGED BETWEEN HIGH PRESSURE ALONG THE EAST COAST AND A COLD FRONT
OVER THE PLAINS. THE FRONT SHOULD FINALLY CROSS INDIANA
THURSDAY...THEN BE FOLLOWED BY HIGH PRESSURE THAT WILL LINGER
THROUGH THE WEEK.
&&
.NEAR TERM /TODAY/...
ISSUED AT 203 AM EDT SUN JUN 17 2012
POPS ARE THE PROBLEM OF THE DAY.
STORMS TO OUR WEST ARE DYING AS THEY SLOWLY MOVE EAST...BUT ARE
APT TO LEAVE BOUNDARY SOMEWHERE OVER US TODAY. NONE OF THE
SYNOPTIC MODELS ARE LIKELY TO HANDLE THIS WELL. HOWEVER...THEY
ALL HAVE A WEAK WAVE CROSSING ALOFT TODAY WHICH WILL LIKELY IGNITE
CONVECTION WHEREVER THE BOUNDARY IS.
TO REALLY GET A GOOD HANDLE ON THE SITUATION...WE MAY HAVE TO WAIT
UNTIL THE RUC FORECASTS START EXTENDING WELL INTO THE DAY PERIOD.
FOR NOW I WILL BASICALLY USE A MET MAV ENSEMBLE TO GET THE BEST
OF EACH. HOWEVER...I WILL AT LEAST BE CHANCE AS OPPOSED TO SLIGHT
CHANCE EVERYWHERE. WILL SAY LIKELY IN NORTHWEST. WHILE
PRECIPITATION NOW THERE MAY DIE BY 12Z...NEED TO ACCOUNT FOR IT
SOMEWHAT WITH THIS PACKAGE.
WITH SO MUCH UNCERTAINTY ABOUT CLOUDS AND PRECIPITATION...WILL
TAKE CONSENSUS OF GUIDANCE TEMPERATURES...AGAIN TO CAPTURE
ENSEMBLE EFFECT.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
ISSUED AT 203 AM EDT SUN JUN 17 2012
PROBLEM IS RAIN CHANCES THROUGH MONDAY. AFTER THAT MODELS CONCUR
RIDGE BUILDING OVER AREA SHUTTING PRECIPITATION DOWN.
WE COULD GET STORMS EARLY TONIGHT FROM STUFF THAT FIRES DURING DAY
AND SURVIVES INTO EVENING. AFTER THAT SOME STUFF COULD STILL DEVELOP
IN WARM HUMID AIR UNTIL RIDGE REALLY BUILDS BY TUESDAY EVENING.
DONT SEE HOW I CAN BEAT THE GUIDANCE THIS FAR IN THE FUTURE. WILL
COMBINE MAV AND MET HOPING FOR BEST OF BOTH.
ON TEMPERATURES USING THE MET. MAV HAS NOT BEEN DOING WELL
IN UNSEASONABLE WARMTH LATELY.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
ISSUED AT 245 AM EDT SUN JUN 17 2012
STRONG UPPER LEVEL RIDGE WILL STILL BE IN CONTROL OVER THE AREA
EARLY IN THE LONG TERM PERIOD...HOWEVER GUIDANCE DEPICTS AN UPPER
LEVEL WAVE AND ASSOCIATED COLD FRONT HELPING TO ERODE THE RIDGE
SOMEWHAT AND SHUTTLE IT TO THE EAST THURSDAY AND FRIDAY. THIS
MERITS AT LEAST SOME LOW THUNDERSTORM CHANCES DURING THIS
TIME...AND INITIALIZATION HANDLED THIS RELATIVELY WELL...WITH SOME
TWEAKS.
SURFACE HIGH SETTLES ACROSS THE AREA IN THE WAKE OF THE
FRONT...AND GUIDANCE DEPICTS BROAD RIDGING ALOFT STRENGTHENING TO
OUR WEST OVER THE WEEKEND. THAT SAID...MODELS HINT AT THE
POTENTIAL FOR THUNDERSTORM ACTIVITY...PERHAPS IN THE FORM OF ONE
OR MORE MCS/S...DURING PORTIONS OF THE WEEKEND IN THE NORTHWEST
FLOW. THIS...AND THE SLIGHT CHANCE POPS INTIALIZATION GAVE TO
HANDLE IT...APPEAR REASONABLE...ESPECIALLY AS WE ARE ENTERING THE
TIME OF YEAR WHEN ORGANIZED RIDGE RIDING CONVECTION IN NORTHWEST FLOW
BECOMES RELATIVELY COMMON. DUE TO SIGNIFICANT UNCERTAINTY...CANNOT
JUSTIFY MORE THAN SLIGHT CHANCE POPS FOR PORTIONS OF THE REGION
AT THE MOMENT.
REMAINDER OF BLEND WAS REASONABLE...WITH A FEW MINOR TWEAKS TO
MAX/MIN TEMPS AFTER CONSULTING 850 TEMP PROGS. ASIDE FROM WHAT
LOOKS TO BE BRIEF RETURN TO NEAR NORMAL TEMPS FRIDAY AND
SATURDAY...90 DEGREE HEAT WILL NOT BE GOING ANYWHERE ANYTIME SOON
FOR LENGTHY PERIODS.
&&
.AVIATION /DISCUSSION FOR THE 170600Z TAF ISSUANCE/...
ISSUED AT 1240 AM EDT SUN JUN 17 2012
LINE OF THUNDERSTORMS FROM NEAR KCHI TO KSTL WILL CONTINUE INTO OUR
AREA OVERNIGHT AND WEAKEN AS AN UPPER TROUGH CONTINUES EAST ACROSS
THE GREAT LAKES. RADAR LOOPS INDICATE STORM MAY PUSH INTO THE KLAF
AND KHUF AREA AROUND TAF ISSUANCE AND WILL MENTION PERIOD OF
TEMPO TSRA AT THOSE SITES. IT MAY REACH KIND AND KBMG AFTER
10Z...BUT MUCH OF THE LINE MAY BE BREAKING UP BY THEN SO WILL ONLY
MENTION VCTS AT KBMG AND KIND.
WHATS LEFT OF THUNDERSTORMS WILL CLEAR ALL AREAS BY 15Z. THERE WILL
PROBABLY BE SOME REDEVELOPMENT ACROSS THE SOUTHEAST HALF OF INDIANA
SUNDAY AFTERNOON AS DAYTIME HEATING TAKES HOLD. THE NAM MODEL
INDICATES MOST OF THIS REDEVELOPMENT WILL OCCUR EAST AND SOUTHEAST
OF KIND AND KBMG TAFS AND WITH LOW CONFIDENCE OF MORE THUNDER
AFFECTING ANY TAFS WILL LEAVE OUT MENTION FOR NOW. MODELS INDICATE
DRIER AIR WILL BE SPREADING IN FROM THE NORTHWEST SUNDAY AFTERNOON
AND EVENING. OVERALL TAFS WILL BE MOSTLY VFR THROUGH THE PERIOD.
WINDS WILL BE 8 KNOTS OR LESS OVERNIGHT AND WEST TO SOUTHWEST AT
10-12 KNOTS SUNDAY WITH LIGHT SOUTHWEST WINDS SUNDAY EVENING.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...JK
NEAR TERM...JK
SHORT TERM...JK
LONG TERM....NIELD
AVIATION...JH
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
203 AM EDT SUN JUN 17 2012
.UPDATE...
THE SYNOPSIS...NEAR TERM AND SHORT TERM SECTIONS HAVE BEEN UPDATED BELOW
&&
.SYNOPSIS...
ISSUED AT 203 AM EDT SUN JUN 17 2012
A WEAK FRONT WILL CROSS INDIANA AND THEN MOVE OFF TO THE NORTHEAST
TODAY. FOR MONDAY THROUGH WEDNESDAY EXPECT THE HOOSIER STATE TO BE
WEDGED BETWEEN HIGH PRESSURE ALONG THE EAST COAST AND A COLD FRONT
OVER THE PLAINS. THE FRONT SHOULD FINALLY CROSS INDIANA
THURSDAY...THEN BE FOLLOWED BY HIGH PRESSURE THAT WILL LINGER
THROUGH THE WEEK.
&&
.NEAR TERM /TODAY/...
ISSUED AT 203 AM EDT SUN JUN 17 2012
POPS ARE THE PROBLEM OF THE DAY.
STORMS TO OUR WEST ARE DYING AS THEY SLOWLY MOVE EAST...BUT ARE
APT TO LEAVE BOUNDARY SOMEWHERE OVER US TODAY. NONE OF THE
SYNOPTIC MODELS ARE LIKELY TO HANDLE THIS WELL. HOWEVER...THEY
ALL HAVE A WEAK WAVE CROSSING ALOFT TODAY WHICH WILL LIKELY IGNITE
CONVECTION WHEREVER THE BOUNDARY IS.
TO REALLY GET A GOOD HANDLE ON THE SITUATION...WE MAY HAVE TO WAIT
UNTIL THE RUC FORECASTS START EXTENDING WELL INTO THE DAY PERIOD.
FOR NOW I WILL BASICALLY USE A MET MAV ENSEMBLE TO GET THE BEST
OF EACH. HOWEVER...I WILL AT LEAST BE CHANCE AS OPPOSED TO SLIGHT
CHANCE EVERYWHERE. WILL SAY LIKELY IN NORTHWEST. WHILE
PRECIPITATION NOW THERE MAY DIE BY 12Z...NEED TO ACCOUNT FOR IT
SOMEWHAT WITH THIS PACKAGE.
WITH SO MUCH UNCERTAINTY ABOUT CLOUDS AND PRECIPITATION...WILL
TAKE CONSENSUS OF GUIDANCE TEMPERATURES...AGAIN TO CAPTURE
ENSEMBLE EFFECT.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
ISSUED AT 203 AM EDT SUN JUN 17 2012
PROBLEM IS RAIN CHANCES THROUGH MONDAY. AFTER THAT MODELS CONCUR
RIDGE BUILDING OVER AREA SHUTTING PRECIPITATION DOWN.
WE COULD GET STORMS EARLY TONIGHT FROM STUFF THAT FIRES DURING DAY
AND SURVIVES INTO EVENING. AFTER THAT SOME STUFF COULD STILL DEVELOP
IN WARM HUMID AIR UNTIL RIDGE REALLY BUILDS BY TUESDAY EVENING.
DONT SEE HOW I CAN BEAT THE GUIDANCE THIS FAR IN THE FUTURE. WILL
COMBINE MAV AND MET HOPING FOR BEST OF BOTH.
ON TEMPERATURES USING THE MET. MAV HAS NOT BEEN DOING WELL
IN UNSEASONABLE WARMTH LATELY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
ISSUED AT 345 PM EDT SAT JUN 16 2012
ENSEMBLES INDICATE A STRONG UPPER RIDGE...CENTERED OVER THE
APPALACHIAN MOUNTAINS...WILL GET REPLACED BY UPPER TROUGHING BY NEXT
WEEKEND AS UPPER ENERGY MOVES THROUGH THE NORTHERN MIDWEST/GREAT
LAKES AROUND THURSDAY AND FRIDAY. ENSEMBLES SUGGEST THE BEST THREAT
FOR PRECIPITATION DURING THIS PERIOD REMAINS THURSDAY AND FRIDAY AS
THE UPPER SHORT WAVE TROUGH MOVES THROUGH. WILL CONTINUE WITH THE
IDEA OF THE PREVIOUS FORECAST IN KEEPING THINGS DRY ON
WEDNESDAY...AND CHANCE POPS THURSDAY AND FRIDAY. A FEW ENSEMBLES
HINT AT MAYBE SOME INSTABILITY SHOWERS ON SATURDAY UNDER THE UPPER
TROUGH...BUT THE MAJORITY OF THE MEMBERS ARE DRY. WILL GO WITH A DRY
FORECAST ON SATURDAY FOR NOW.
&&
.AVIATION /DISCUSSION FOR THE 170600Z TAF ISSUANCE/...
ISSUED AT 1240 AM EDT SUN JUN 17 2012
LINE OF THUNDERSTORMS FROM NEAR KCHI TO KSTL WILL CONTINUE INTO OUR
AREA OVERNIGHT AND WEAKEN AS AN UPPER TROUGH CONTINUES EAST ACROSS
THE GREAT LAKES. RADAR LOOPS INDICATE STORM MAY PUSH INTO THE KLAF
AND KHUF AREA AROUND TAF ISSUANCE AND WILL MENTION PERIOD OF
TEMPO TSRA AT THOSE SITES. IT MAY REACH KIND AND KBMG AFTER
10Z...BUT MUCH OF THE LINE MAY BE BREAKING UP BY THEN SO WILL ONLY
MENTION VCTS AT KBMG AND KIND.
WHATS LEFT OF THUNDERSTORMS WILL CLEAR ALL AREAS BY 15Z. THERE WILL
PROBABLY BE SOME REDEVELOPMENT ACROSS THE SOUTHEAST HALF OF INDIANA
SUNDAY AFTERNOON AS DAYTIME HEATING TAKES HOLD. THE NAM MODEL
INDICATES MOST OF THIS REDEVELOPMENT WILL OCCUR EAST AND SOUTHEAST
OF KIND AND KBMG TAFS AND WITH LOW CONFIDENCE OF MORE THUNDER
AFFECTING ANY TAFS WILL LEAVE OUT MENTION FOR NOW. MODELS INDICATE
DRIER AIR WILL BE SPREADING IN FROM THE NORTHWEST SUNDAY AFTERNOON
AND EVENING. OVERALL TAFS WILL BE MOSTLY VFR THROUGH THE PERIOD.
WINDS WILL BE 8 KNOTS OR LESS OVERNIGHT AND WEST TO SOUTHWEST AT
10-12 KNOTS SUNDAY WITH LIGHT SOUTHWEST WINDS SUNDAY EVENING.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...JK
NEAR TERM...JK
SHORT TERM...JK
LONG TERM....RYAN
AVIATION...JH
AREA FORECAST DISCUSSION
NWS WICHITA KS
1212 AM CDT SUN JUN 17 2012
.AVIATION...06Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
SCATTERED SHOWERS AND THUNDERSTORMS OVER SOUTHWEST KANSAS CONTINUE
TO DRIFT SLOWLY EASTWARD WHILE WEAKENING AND ARE EXPECTED TO
DIMINISH PRIOR TO IMPACTING CENTRAL/SOUTH CENTRAL KANSAS. LOW T/TD
SPREADS MAY LEAD TO PATCHY TRANSIENT MVFR VISIBILITIES/CIGS GIVEN
RECENT RAINS...ESPECIALLY WHERE SKIES CLEAR TOWARD SUNRISE. BREEZY
SOUTH TO SOUTHWEST WINDS ARE EXPECTED BY AROUND 15Z WITH PRESSURE
FALLS ACROSS THE CENTRAL HIGH PLAINS.
MWM
&&
.PREV DISCUSSION... /ISSUED 635 PM CDT SAT JUN 16 2012/
AVIATION...00Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
MULTIPLE BOUNDARIES AND WEAK FLOW MADE FOR ANOTHER TOUGH AVIATION
FORECAST. WHILE THUNDERSTORMS CANNOT BE RULED OUT AT ANY SITE...THE
MOSTLY LIKELY SITE WOULD BE KCNU. BASED ON LATEST LAPS 500M CIN/CAPE
ANALYSIS...CAPPING IS NEARLY GONE OVER SOUTHEAST KS/ROUGHLY EAST
OF I-35 WITH CAPE RUNNING BETWEEN 2800-3100 J/KILOGRAM IN THIS AREA.
JUST NOT SURE THERE IS ENOUGH FORCING TO GET STORMS TO GO...AND
WILL KEEP ALL TAFS DRY FOR NOW...AND UPDATE IF/WHEN STORMS START
TO GO. OTHERWISE...SHOULD SEE LIGHT/VARIABLE WINDS OVERNIGHT AND THEN
A INCREASE FROM THE SOUTH DURING THE DAYLIGHT HOURS ON SUN. SOME
CUMULUS ANTICIPATED WITH HEATING ON SUN AS WELL. VFR CONDITIONS
ANTICIPATED EXCEPT NEAR THUNDERSTORMS. -HOWERTON
PREV DISCUSSION... /ISSUED 521 PM CDT SAT JUN 16 2012/
UPDATE...
THUNDERSTORM INITIATION...OTHER THAN MAYBE A FEW ISOLATED
STORMS...IS STARTING TO LOOK LESS LIKELY DUE TO DECREASING
CONVERGENCE ALONG THE FRONT. ADDITIONALLY...LARGE-SCALE
SUBSIDENCE IN WAKE OF MID-MISSOURI VALLEY MCV...EVIDENCED BY
700-500MB RIDGING OVER KS...IS LIKELY INHIBITING CONVECTIVE
INITIATION AS WELL. GIVEN STRONGLY UNSTABLE CONDITIONS OVER
SOUTHEAST KS DO NOT WANT TO COMPLETELY RULE ANYTHING OUT
YET...BUT IF CURRENT TREND CONTINUES WILL LIKELY BE DECREASING
EVENING POPS.
KLEINSASSER
PREV DISCUSSION... /ISSUED 320 PM CDT SAT JUN 16 2012/
DISCUSSION...
FORECAST CHALLENGES/HIGHLIGHTS FOCUS AROUND THUNDERSTORM CHANCES
LATE THIS AFTERNOON-TONIGHT...WITH THUNDERSTORM CHANCES POSSIBLY
RETURNING BY LATE WEDNESDAY. TEMPERATURES WILL LIKELY BE ABOVE
NORMAL MUCH OF THE NEXT 7 DAYS.
SYNOPSIS...AT THE SURFACE...A WEAK COLD FRONT CURRENTLY STRETCHES
FROM NEAR THE KC METRO...WSW INTO CENTRAL AND WESTERN KS. OLD
OUTFLOW FROM THUNDERSTORM COMPLEX EARLY THIS MORNING HAS NEARLY
WASHED OUT OVER CENTRAL OK. IN THE MID/UPPER LEVELS...AN IMPRESSIVE
MCV (FROM ACTIVITY EARLY THIS MORNING) IS CURRENTLY PROGRESSING
NORTHEAST OVER THE MID-MISSOURI VALLEY...WITH A MUCH SMALLER MCV
(FROM TX PANHANDLE ACTIVITY LAST NIGHT) MEANDERING OVER
NORTHWEST/NORTH-CENTRAL OK.
THIS AFTERNOON-TONIGHT...AIRMASS IS DESTABILIZING NICELY OVER
SOUTHERN/SOUTHEAST KS...ALONG/SOUTH OF THE WEAK COLD FRONT
PROGRESSING SLOWLY SOUTH ACROSS KS. DESPITE SUBSIDENCE IN WAKE OF
MCV TO THE NORTHEAST...THINKING CONTINUED HEATING/CONVERGENCE WILL
ALLOW WIDELY SCATTERED STORMS TO FIRE ALONG THE FRONT BY LATE
AFTERNOON...LIKELY ZIPPERING DOWN INTO SOUTHEAST KS FROM THE
NORTHEAST. HAVE THE HIGHEST CONFIDENCE WITH THIS SCENARIO PER
LATEST HRRR AND OUN WRF MODELS. ISOLATED TO WIDELY SCATTERED
ACTIVITY COULD EVEN BUBBLE FURTHER WSW ALONG THE FRONT INTO SOUTH-
CENTRAL KS...POSSIBLY AIDED BY WEAK NORTHERN OK MCV. ANOTHER
POSSIBLE AREA FOR CONVECTIVE INITIATION IS ALONG WESTERN PORTIONS
OF THE FRONT OVER WEST/SOUTHWEST KS...WITH THIS ACTIVITY POSSIBLY
ROLLING ESE INTO SOUTH-CENTRAL KS THIS EVENING AIDED BY
STRENGTHENING LLJ...ALTHOUGH LOWER INSTABILITY PRECLUDES HIGHER
CONFIDENCE IS THIS AREA. ALL-IN-ALL...AMPLE INSTABILITY & HIGH
PRECIPITABLE WATERS WITH MARGINAL DEEP LAYER SHEAR WILL PROMOTE
STRONG/SEVERE STORMS CAPABLE OF LARGE HAIL (AT LEAST
INITIALLY)...DAMAGING WINDS AND TORRENTIAL RAINFALL...WITH THE
HIGHEST CONFIDENCE AGAIN OVER SOUTHEAST KS. ACTIVITY COULD TEND TO
LINGER OVER FAR SOUTHERN KS WELL INTO THE EVENING...ESPECIALLY IF
SHORT-TERM GUIDANCE IS CORRECT IN STALLING THE BOUNDARY OVER FAR
SOUTHERN KS...BUT CONFIDENCE IS LOW IN THIS SCENARIO LASTING PAST
MIDNIGHT. SEVERE THREAT SHOULD END BY MID/LATE EVENING.
ANTICIPATING CENTRAL KS WILL REMAIN DRY THROUGH THE NIGHT.
SUNDAY...WITH THE POSSIBILITY OF ANOTHER MCV PRODUCED BY OVERNIGHT
CONVECTION...ENDED UP LEAVING SLIGHT CHANCE POPS IN THE FORECAST
GENERALLY EAST OF I-135. HOWEVER...THINK MOST AREAS WILL REMAIN
DRY...AS DEVELOPING STRONG SOUTHERLY FLOW WASHES OUT THE OLD FRONTAL
BOUNDARY BY LATE MORNING. GOOD MIXING AND WARMING LOW-LEVEL
THICKNESSES SHOULD ALLOW TEMPERATURES TO SOAR INTO THE MID-UPPER
90S...WITH NEAR 90 DEGREES OVER SOUTHEAST KS.
MONDAY-TUESDAY...CONTINUED HOT...DRY AND WINDY WEATHER WILL LIKELY
CONTINUE THROUGH MID-WEEK...AS MEDIUM RANGE CONSENSUS SUPPORTS
STRENGTHENING HIGH PLAINS LOW PRESSURE AHEAD OF APPROACHING NORTHERN
ROCKIES SHORTWAVE ENERGY...ALONG WITH BUILDING HEIGHTS/THICKNESS
OVER THE CENTRAL/EASTERN CONUS. HIGHS WELL INTO THE 90S AND LOWS IN
THE 70S APPEAR LIKELY.
WEDNESDAY-WEEKEND...MEDIUM RANGE CONSENSUS SUGGESTS A FRONTAL
BOUNDARY WILL ATTEMPT TO ENCROACH ON THE REGION FROM THE
NORTHWEST...WHICH COULD RESULT IN THUNDERSTORM CHANCES ARRIVING BY
LATE WEDNESDAY...MAINLY OVER THE NORTHERN HALF OF KS. SUSPECT THIS
FRONT WILL HAVE A TOUGH TIME PENETRATING VERY FAR SOUTH...SO OTHER
THAN SOME MODERATING TEMPERATURES MID WEEK...WARMING TEMPERATURES BY
THE WEEKEND APPEAR LIKELY...AS SOUTHERN/WESTERN CONUS RIDGE BUILDS
BACK IN.
KLEINSASSER
AVIATION...18Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
MAIN AVIATION CONCERN WILL BE CONVECTIVE TRENDS THIS AFTERNOON INTO
THE EVENING HOURS.
OVERNIGHT STORMS HAVE LEFT SOME UPPER ENERGY THAT IS SPINNING OVER
NORTHEAST KS. THIS FEATURE HAS PUSHED THE COLD FRONT FURTHER SOUTH
THAN WHAT WAS PREVIOUSLY EXPECTED. THEREFORE THE BETTER PRECIP
CHANCES FOR LATE THIS AFTERNOON AND THIS EVENING WILL BE GENERALLY
EAST OF THE KS TURNPIKE. SO TOOK VCTS OUT EVERYWHERE BUT KICT AND
KCNU WHICH MUCH HIGHER CONFIDENCE IN STORMS OCCURRING AT KCNU.
CONFIDENCE IS HIGH THAT THE REMAINDER OF THE TAF SITES WILL
EXPERIENCE VFR CONDITIONS THROUGH THIS TAF PERIOD.
LAWSON
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 70 94 74 96 / 30 20 10 0
HUTCHINSON 69 95 74 97 / 20 10 10 0
NEWTON 68 93 74 95 / 30 20 10 0
ELDORADO 68 91 73 93 / 30 20 10 0
WINFIELD-KWLD 70 92 73 94 / 40 20 10 0
RUSSELL 66 97 74 99 / 20 10 10 0
GREAT BEND 66 97 74 99 / 20 10 10 0
SALINA 68 95 74 97 / 20 10 10 0
MCPHERSON 68 95 74 97 / 20 20 10 0
COFFEYVILLE 70 90 72 92 / 40 20 10 0
CHANUTE 70 90 72 92 / 40 20 10 0
IOLA 70 90 72 92 / 40 20 10 0
PARSONS-KPPF 70 90 72 92 / 40 20 10 0
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS JACKSON KY
306 AM EDT SUN JUN 17 2012
.UPDATE...
ISSUED AT 150 AM EDT SUN JUN 17 2012
SKIES HAVE CLEARED OUT IN THE WAKE OF CONVECTION AS AN UPPER LEVEL
RIDGE AXIS REMAINS IN PLACE ALOFT. CONVECTION FIRING UP FURTHER
UPSTREAM IS ALSO SHOWING A GOOD WEAKENING TREND AND BOTH THE GFS AND
NAM LOOKED OVERPLAYED WITH BRINGING PRECIPITATION FURTHER EASTWARD
THE REST OF TONIGHT. PREFER THE LATEST HRRR MODEL...WHICH CAPTURES
THIS LULL FAIRLY WELL AND THEN BRINGS IN SOME ISOLATED ACTIVITY INTO
THE BLUEGRASS TOWARDS 12Z. HAVE FRESHENED UP THE REST OF THE GRIDS AS
WELL AS TO JIVE BETTER WITH THE LATEST OBSERVATIONAL TRENDS.
UPDATE ISSUED AT 845 PM EDT SAT JUN 16 2012
UPDATED THE FORECAST TO REFLECT CURRENT CONDITIONS AND MODEL TRENDS. A
LINE OF THUNDERSTORMS FORMED LATE THIS AFTERNOON FROM FLEMING TO
HARLAN COUNTY AND BECAME QUITE ACTIVE FROM AROUND 5 TO 8 PM. MOST OF
THE STORMS WERE JUST HEAVY RAINERS...HOWEVER A COUPLE OF THE STORMS
PULSED UP TO NEAR SEVERE WEATHER CRITERIA. AS OF THIS WRITING...NO
SEVERE WEATHER REPORTS HAVE BEEN RECEIVED...NOR ARE THEY EXPECTED.
FOR THE NEXT 24 HOURS...THE MODELS HAVE SOME DIFFERENT SOLUTIONS AS
TO WHEN TO EXPECT THE RAINFALL. FOR THE LAST TWO DAYS...THERE HAS
BEEN AN ACTIVE PERIOD OF CONVECTION FROM THE EARLY MORNING THROUGH
THE LATE AFTERNOON. SOME OF THE MODELS HAVE ALSO PICKED UP ON THIS.
AS SUCH...WENT WITH A MODEL BLEND TO BRING SOME STORMS INTO THE AREA
NEAR DAWN AS THE 18 GMT GFS WAS INDICATING AND THE THEN WENT WITH A
BRIEF LULL BEFORE INCREASING THE CHANCES AGAIN IN THE AFTERNOON AND
EVENING. DUE TO THE DIVERSE MODEL SOLUTIONS...CONFIDENCE IS A BIT LOW
RIGHT NOW. ALSO EXPECTING SOME FOG IN THE VALLEYS NEAR LOCATIONS THE
RECEIVED RAINFALL TONIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 308 PM EDT SAT JUN 16 2012
CONVECTION ACROSS THE AREA IS FINALLY ON THE WANE...AND EXPECT
SHOWERS AND THUNDERSTORMS TO CONTINUE TO DIMINISH THIS EVENING WITH
LOSS OF DAYTIME HEATING. SHORT RANGE MODELS DID NOT HANDLE TODAY/S
CONVECTION VERY WELL...AND AM NOT VERY CONFIDENT IN MODEL SOLUTIONS
FOR POTENTIAL CONVECTION OVER THE NEXT 24 HOURS. MODELS INSIST ON
AT LEAST A CHANCE OF SHOWERS OVERNIGHT...THOUGH WITH DIFFERENT
SCENARIOS ON LOCATION AND TIMING. HAVE DECIDED TO GO WITH A DRY
FORECAST OVERNIGHT...BRINGING A SLIGHT CHANCE TO THE FAR WEST BY
EARLY SUNDAY. EXPECT SCATTERED CONVECTION AGAIN ON SUNDAY. WITH
SHORT WAVE SWINGING THROUGH THE GREAT LAKES/OH VALLEY SUNDAY AND AN
APPROACHING COLD FRONT EXPECT CONVECTION TO BE A LITTLE MORE
ORGANIZED BY SUNDAY AFTERNOON INTO SUNDAY NIGHT. WILL CONTINUE IDEA
OF SOME SHOWERS LINGERING INTO THE DAY ON MONDAY. MADE ONLY SLIGHT
MODIFICATION TO TEMPERATURE FORECAST FOR THE SHORT TERM PART OF THE
FORECAST.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 300 AM EDT SUN JUN 17 2012
A STRONG UPPER LEVEL RIDGE SHOWS A WEAKNESS OVER THE ERN OHIO
VALLEY. THIS WEAKNESS HAS A FEW SHOWERS AT THE SFC BUT THEY ARE WELL
NORTH OF ERN KY...SO THIS FCST STARTS OUT DRY. WITH THE SFC HIGH
LOCATED OFF THE CAROLINA COAST...THE FLOW WILL BE PREDOMINATELY FROM
THE SW. THIS WILL BOOST TEMPERATURES INTO THE LOWER 90S. EXPECT THIS
SCENERIO TO REMAIN IN PLACE THROUGH MOST OF THE WEEK. BY EARLY
FRIDAY THE UPPER RIDGE WILL RETROGRADE TO THE HIGH PLAINS AND WE
WILL BE IN A NW FLOW ALOFT ONCE MORE. THIS WILL ALLOW A SFC TROF TO
DECEND INTO THE OHIO VALLEY AND BRING A CHANCE FOR SHOWERS AND
THUNDERSTORMS TO THE AREA FRIDAY. THE PCPN AND ACCOMPANING CLOUD
COVER WILL SUPPRESS HIGH TEMPS TO THE UPPER 80S WITH A FEW LOWER 90S
POSSIBLE. THE POSSIBILITY FOR PCPN WILL CONTINUE INTO THE WEEKEND AS
THE FRONT STALLS ACROSS THE LENGTH OF THE COMMONWEALTH WITH THE BEST
CHANCE FOR RAIN OVER OUR NRN COUNTIES. TEMPS WILL ALSO CONTINUE
SLIGHTLY BELOW MID WEEK LEVELS AS HIGHS ON SATURDAY WILL BE MOSTLY
CONTAINED IN THE UPPER 80S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 150 AM EDT SUN JUN 17 2012
MVFR TO AS LOW AS LIFR FOG WILL BE SPOTTY ACROSS THE AREA...MAINLY
TARGETING LOCATIONS THAT RECEIVED HEAVIER PRECIPITATION AS WELL AS
THE DEEPER RIVER VALLEYS. AN UPPER LEVEL DISTURBANCE WILL PASS
THROUGH THE AREA TOMORROW...BRINGING SCATTERED SHOWERS AND
THUNDERSTORMS TO MOST LOCATIONS. HAVE LET THE VCTS REMAIN INTACT FOR
NOW THROUGHOUT THE DAY AS CONFIDENCE IN TIMING INDIVIDUAL BOUTS OF
CONVECTION REMAINS LOW.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...SBH
LONG TERM....DUSTY
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS JACKSON KY
150 AM EDT SUN JUN 17 2012
.UPDATE...
ISSUED AT 150 AM EDT SUN JUN 17 2012
SKIES HAVE CLEARED OUT IN THE WAKE OF CONVECTION AS AN UPPER LEVEL
RIDGE AXIS REMAINS IN PLACE ALOFT. CONVECTION FIRING UP FURTHER
UPSTREAM IS ALSO SHOWING A GOOD WEAKENING TREND AND BOTH THE GFS AND
NAM LOOKED OVERPLAYED WITH BRINGING PRECIPITATION FURTHER EASTWARD
THE REST OF TONIGHT. PREFER THE LATEST HRRR MODEL...WHICH CAPTURES
THIS LULL FAIRLY WELL AND THEN BRINGS IN SOME ISOLATED ACTIVITY INTO
THE BLUEGRASS TOWARDS 12Z. HAVE FRESHENED UP THE REST OF THE GRIDS AS
WELL AS TO JIVE BETTER WITH THE LATEST OBSERVATIONAL TRENDS.
UPDATE ISSUED AT 845 PM EDT SAT JUN 16 2012
UPDATED THE FORECAST TO REFLECT CURRENT CONDITIONS AND MODEL TRENDS. A
LINE OF THUNDERSTORMS FORMED LATE THIS AFTERNOON FROM FLEMING TO
HARLAN COUNTY AND BECAME QUITE ACTIVE FROM AROUND 5 TO 8 PM. MOST OF
THE STORMS WERE JUST HEAVY RAINERS...HOWEVER A COUPLE OF THE STORMS
PULSED UP TO NEAR SEVERE WEATHER CRITERIA. AS OF THIS WRITING...NO
SEVERE WEATHER REPORTS HAVE BEEN RECEIVED...NOR ARE THEY EXPECTED.
FOR THE NEXT 24 HOURS...THE MODELS HAVE SOME DIFFERENT SOLUTIONS AS
TO WHEN TO EXPECT THE RAINFALL. FOR THE LAST TWO DAYS...THERE HAS
BEEN AN ACTIVE PERIOD OF CONVECTION FROM THE EARLY MORNING THROUGH
THE LATE AFTERNOON. SOME OF THE MODELS HAVE ALSO PICKED UP ON THIS.
AS SUCH...WENT WITH A MODEL BLEND TO BRING SOME STORMS INTO THE AREA
NEAR DAWN AS THE 18 GMT GFS WAS INDICATING AND THE THEN WENT WITH A
BRIEF LULL BEFORE INCREASING THE CHANCES AGAIN IN THE AFTERNOON AND
EVENING. DUE TO THE DIVERSE MODEL SOLUTIONS...CONFIDENCE IS A BIT LOW
RIGHT NOW. ALSO EXPECTING SOME FOG IN THE VALLEYS NEAR LOCATIONS THE
RECEIVED RAINFALL TONIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 308 PM EDT SAT JUN 16 2012
CONVECTION ACROSS THE AREA IS FINALLY ON THE WANE...AND EXPECT
SHOWERS AND THUNDERSTORMS TO CONTINUE TO DIMINISH THIS EVENING WITH
LOSS OF DAYTIME HEATING. SHORT RANGE MODELS DID NOT HANDLE TODAY/S
CONVECTION VERY WELL...AND AM NOT VERY CONFIDENT IN MODEL SOLUTIONS
FOR POTENTIAL CONVECTION OVER THE NEXT 24 HOURS. MODELS INSIST ON
AT LEAST A CHANCE OF SHOWERS OVERNIGHT...THOUGH WITH DIFFERENT
SCENARIOS ON LOCATION AND TIMING. HAVE DECIDED TO GO WITH A DRY
FORECAST OVERNIGHT...BRINGING A SLIGHT CHANCE TO THE FAR WEST BY
EARLY SUNDAY. EXPECT SCATTERED CONVECTION AGAIN ON SUNDAY. WITH
SHORT WAVE SWINGING THROUGH THE GREAT LAKES/OH VALLEY SUNDAY AND AN
APPROACHING COLD FRONT EXPECT CONVECTION TO BE A LITTLE MORE
ORGANIZED BY SUNDAY AFTERNOON INTO SUNDAY NIGHT. WILL CONTINUE IDEA
OF SOME SHOWERS LINGERING INTO THE DAY ON MONDAY. MADE ONLY SLIGHT
MODIFICATION TO TEMPERATURE FORECAST FOR THE SHORT TERM PART OF THE
FORECAST.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 308 PM EDT SAT JUN 16 2012
A STRONG UPPER RIDGE WILL DOMINATE THE FIRST PART OF THE PERIOD WITH
HOT AND MAINLY DRY WEATHER. WOULD NOT COMPLETELY RULE OUT ISOLATED
CONVECTIVE PRECIP...ESPECIALLY OVER THE HIGHER TERRAIN IN THE
SOUTHEAST. HOWEVER...WILL CONTINUE TO KEEP POPS BELOW 20 PERCENT.
AN UPPER TROUGH HEADING EAST SOUTHEAST IS STILL EXPECTED TO FLATTEN
THE RIDGE AND SUPPRESS IT SOUTHWARD LATE IN THE WEEK. THE GFS ALLOWS
CONVECTION TO DEVELOP ON THURSDAY AS THIS STARTS TO HAPPEN...BUT
OTHER MODELS REMAIN DRY. WITHOUT A DISCERNIBLE SIGNIFICANT FEATURE
TO FOCUS CONVECTION...AND WITH WEAK FLOW...THINK THAT IF PRECIP
OCCURS THE COVERAGE WOULD REMAIN LOW. WILL USE A 20 PERCENT POP FOR
THURSDAY AFTERNOON AND EVENING. ON FRIDAY AND FRIDAY NIGHT THE UPPER
TROUGH CONTINUES TO AMPLIFY OVER THE EASTERN CONUS AND ITS
ASSOCIATED COLD FRONT MOVES IN FROM THE NORTHWEST. WITH THE MORE
FAVORABLE CONDITIONS FOR CONVECTION...WILL USE CHANCE POPS CLOSE TO
MEXMOS FOR THIS TIME FRAME.
ON SATURDAY THE MODELS SHOW THE TROUGH AXIS PASSING TO OUR EAST AND
THE WEAKENING SURFACE FRONT DROPPING TO OUR SOUTH. ANY LINGERING
PRECIP WILL END AND DRIER AND AT LEAST SOMEWHAT COOLER AIR SHOULD
BEGIN TO ARRIVE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 150 AM EDT SUN JUN 17 2012
MVFR TO AS LOW AS LIFR FOG WILL BE SPOTTY ACROSS THE AREA...MAINLY
TARGETING LOCATIONS THAT RECEIVED HEAVIER PRECIPITATION AS WELL AS
THE DEEPER RIVER VALLEYS. AN UPPER LEVEL DISTURBANCE WILL PASS
THROUGH THE AREA TOMORROW...BRINGING SCATTERED SHOWERS AND
THUNDERSTORMS TO MOST LOCATIONS. HAVE LET THE VCTS REMAIN INTACT FOR
NOW THROUGHOUT THE DAY AS CONFIDENCE IN TIMING INDIVIDUAL BOUTS OF
CONVECTION REMAINS LOW.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...SBH
LONG TERM....HAL
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
524 AM EDT SUN JUN 17 2012
.SHORT TERM...(TODAY)
ISSUED AT 521 AM EDT SUN JUN 17 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A SHORTWAVE TROF FROM NRN
MANITOBA TO THE UPPER GREAT LAKES BEGINNING TO BE FORCED NE DUE TO
RIDGE EXTENDING FROM THE OHIO VALLEY TO QUEBEC. STRONG SURGE OF
DRIER AIR IS FOLLOWING SHORTWAVE PER 00Z SOUNDINGS WHICH SHOWED
PRECIPITABLE WATER DOWN BLO ONE-HALF INCH OVER THE DAKOTAS.
IMPRESSIVELY DRY AIR WAS NOTED BTWN ROUGHLY 700-500MB ON 00Z
KINL/KBIS SOUNDINGS. DWPT DEPRESSIONS WERE WELL IN EXCESS OF 30C.
KBIS SOUNDING ALSO SHOWED A DRY WELL-MIXED BOUNDARY LAYER. THIS IS
THE AIR MASS THAT WILL BE QUICKLY SHIFTING ACROSS THE AREA TODAY...
RESULTING IN A WARM DAY WITH COMFORTABLE HUMIDITY LEVELS. MIXING TO
800-750MB ON FCST SOUNDINGS YIELDS MAX TEMPS IN THE MID 70S TO LWR
80S. WEAKENING WRLY BOUNDARY LAYER FLOW THIS AFTN WILL ALLOW LAKE
BREEZE DEVELOPMENT TO PROVIDE SOME AFTN COOLING NEAR THE GREAT
LAKES. DRY AIR AVBL TO MIX DOWN SHOULD RESULT IN SFC DWPTS FALLING
TO THE UPPER 40S/LWR 50S IN GENERAL AWAY FROM LAKE MODIFICATION.
SOME LOW/MID 40S NOT OUT OF THE QUESTION GIVEN MAGNITUDE OF DRY AIR
ALOFT. SUN WILL MIX WITH HIGHER BASED CU DURING THE DAY.
AS FAST AS THE DRYING OCCURRED TODAY...MOISTURE WILL QUICKLY RETURN
TONIGHT ON STRENGTHENING SW FLOW IN RESPONSE TO SHORTWAVE ENERGY
RACING ACROSS THE NRN PLAINS. 850MB THETA-E ADVECTION/MOISTURE
ADVECTION IS IMPRESSIVE TONIGHT AS LOW-LEVEL JET RAMPS UP TO 40-50KT
AND TAKES AIM AT UPPER MI. WHILE BEST MUCAPE TO THE SW SHOULD RESULT IN
STRONGER CONVECTION OCCURRING TO THE SW/S AND THUS INTERCEPTING SOME
OF THE MOISTURE TRANSPORT TO UPPER MI...OVERALL DEGREE OF DEEP LAYER
FORCING TO THE N AND BUILDING 850-300MB THICKNESS RIDGE FARTHER N
WITH TIME SUGGEST CONVECTIVE DEVELOPMENT SHOULD EXTEND N AND NE WITH
TIME AS WELL. WITH EXPECTATION OF STRONGER CONVECTION TO THE S/SW
INTERCEPTING INSTABILITY TRANSPORT...NOT ANTICIPATING ANY SVR STORMS
TONIGHT. HOWEVER...SHOULD STRONGER STORMS TO THE S/SW WEAKEN...
ADVECTION OF INSTABILITY TO THE NE COMBINED WITH MARGINAL EFFECTIVE
DEEP LAYER SHEAR COULD LEAD TO SOME HAIL PRODUCING STORMS.
.LONG TERM...(TONIGHT THROUGH SATURDAY)
ISSUED AT 521 AM EDT SUN JUN 17 2012
EXPECT A GOOD CHANCE OF SHOWER AND THUNDERSTORM ACTIVITY MOST
PERIODS THROUGH WEDNESDAY NIGHT...ALONG WITH PATCHY FOG OVER
PORTIONS OF LAKE SUPERIOR. WE BEGIN THE PERIOD WITH W/SW FLOW AT
500MB...WITH HIGH PRESSURE BUILDING ACROSS THE MID ATLANTIC STATES
AND A SERIES OF WAVES SLIDE ACROSS OR NORTH OF UPPER MI.
WILL LOOK FOR A POTENTIAL MCS TO PUSH ACROSS THE AREA MONDAY
AFTERNOON INTO THE EVENING HOURS...AS THE NEARING SFC LOW SHIFTS FROM
THE EASTERN DAKOTAS AT 06Z MONDAY AND CROSSES MN MONDAY AFTERNOON
BEFORE EJECTING ACROSS LAKE SUPERIOR AND ONTARIO. CONTINUE TO
HIGHLIGHT STRONG WINDS AND HAIL THREAT IN THE HWO. EXPECT STRONG
WINDS JUST OFF THE SFC FROM 4-13Z MONDAY W...08-17Z MONDAY S CENTRAL
/SLIGHTLY LESS PRONOUNCED AND SLOWER OFF THE GFS/...AND MORE LIKE 12Z
MON-00Z TUE E...IN THE 50-60KT RANGE. LLWS WILL BE LIKELY A THREAT
FOR FOR AVIATION USERS...WITH STRONG WINDS JUST ABOVE THE SFC AND
ALOFT. EXPECT DCAPE VALUES NEAR 1K J/KG NEAR THE WI BORDER BY
18Z...WITH STRONG WINDS BEING A POSSIBILITY WITH ANY TSRA THAT
DEVELOPS. 0-2KM LAPSE RATES LOOK TO TOP OUT AROUND 6-7C/KM...WITH A
THIN LINE UP TO AROUND 8C/KM OVER THE INTERIOR W HALF OF UPPER MI BY
00Z TUESDAY...LINING UP WITH 1K-2K J/KG CAPE VALUES. EVEN THE 0-3KM
CAPE IS 0.5-1K J/KG OVER THE W HALF BY 18Z...WITH A CONTINUATION
CENTRAL AND E THROUGH 00Z TUE. CIN LOOKS TO BE AOB 40 J/KG OVER THE
INTERIOR W HALF...WITH AN INDICATION OF ELEVATED STORMS CENTRAL AND E
OF A LINE FROM ALGER TO DELTA COUNTY AT LEAST INITIALLY. EXPECT TO
SEE STRONGER STORMS NEARING FROM THE WSW...TO DIMINISH AS THEY PUSH
INTO THE LESS FAVORABLE AREAS OF CENTRAL AND E UPPER MI.
WHILE THE COLD FRONT BRIEFLY SINKS JUST SE OF THE CWA MONDAY
NIGHT...IT WILL RETURN IN THE FORM OF A WARM FRONT TUESDAY
AFTERNOON...IN RESPONSE TO THE NEXT SFC LOW EDGING ACROSS MN FROM
THE CENTRAL PLAINS. CAPE VALUES AGAIN NEAR 1K J/KG TUESDAY AS THIS
LOW TOO PUSHES ACROSS W LAKE SUPERIOR AND INTO ONTARIO TUESDAY NIGHT
INTO EARLY WEDNESDAY. ATTEMPTED TO DRY OUT AREAS NEAR LAKE MI
TUESDAY NIGHT...OUT AHEAD OF THE APPROACHING COLD FRONT. TIMING OF
THE COLD FRONT IS A BIT TRICKY...BUT SHOULD BE OVER THE W THIRD OF
THE CWA BY AT LEAST 18Z WEDNESDAY. COMPARING MODEL OUTPUT...THE
17/06Z NAM IS ON THE QUICK END OF MODEL SOLUTIONS AT LEAST SFC
WISE...WITH THE 17/00Z RUN OF THE CANADIAN AT LEAST 12 HOURS BEHIND
THE NAM. THE GFS AND ECMWF LOOK TO BE BETTER SOLUTIONS FOR THE
PROGRESSION OF THIS SYSTEM.
ALTHOUGH SLIGHT CHANCE POPS LINGER INTO THE DAY THURSDAY...MOST OF
THE SHOWER ACTIVITY SHOULD BE E OF OUR AREA...ALTHOUGH THE 500MB
TROUGH WILL STILL BE OVERHEAD. EXPECT 8-10C 850MB TEMPS THURSDAY
INTO EARLY FRIDAY ON NW-W FLOW BEHIND THE EXITING COLD FRONT...WHICH
SHOULD KEEP SFC TEMPS AT OR SLIGHTLY BELOW NORMAL FOR THIS TIME OF
YEAR. THERE LOOKS TO BE SOME MINOR INDICATIONS IN A PATTERN CHANGE
ALOFT. THE 500MB RIDGE OVER THE MID ATLANTIC/OHIO VALLEY SHOULD
BECOME SUPPRESSED THURSDAY NIGHT...IN RESPONSE TO THE YET ANOTHER
500MB LOW PASSING OVER ONTARIO. THIS LAST ONE LOOKS TO GET HELD UP
OVER S HUDSON BAY/QUEBEC AS THE 500MB RIDGE PUSHES UP ACROSS THE
CENTRAL PLAINS STATES FOR FRIDAY THROUGH SUNDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 135 AM EDT SUN JUN 17 2012
AS DRIER AIR IN THE WAKE OF A COLD FROPA OVERSPREADS UPR MI EARLY
THIS MRNG...EXPECT LINGERING LO CLDS AT CMX/SAW TO GIVE WAY TO VFR
CONDITIONS. A STEADY W WIND IN ADVANCE OF AN APRCHG HI PRES RDG WL
TURN GUSTY WITH DAYTIME HEATING/MIXING BY MID TO LATE MRNG...
ESPECIALLY AT THE MORE EXPOSED CMX LOCATION. THESE WINDS WL DIMINISH
BY LATE AFTN WITH THE PASSAGE OF THE HI PRES AND DIMINSHED MIXING.
ALTHOUGH A FEW -SHRA MAY INVADE IWD BEFORE 06Z TNGT IN THE RETURN SW
FLOW ARND THE DEPARTING HI...CONDITIONS SHOULD REMAIN VFR WITH
LINGERING LLVL DRY AIR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 521 AM EDT SUN JUN 17 2012
A BRIEF RIDGE OF HIGH PRESSURE TODAY...BEHIND THE EXITING SFC
LOW/TROUGH WILL MAKE WAY FOR THE NEXT LOW DEVELOPING OVER S CANADA
AND THE NORTHERN PLAINS STATES. EXPECT THE NORTHERN LOW TO PUSH
ACROSS ONTARIO MONDAY /WITH GUSTS NEARING 30-35KTS CENTRAL AND
E/...WITH A TROUGH EXTENDING THROUGH LS AND INTO NE. GIVEN THE
ADDITIONAL MOISTURE ACROSS THE AREA WITH THE TROUGH NEARBY FOR MUCH
OF THE PERIOD...FOG WILL BE A COMMON THEME. A SECONDARY LOW
OVER NE WILL RIDE UP THE TROUGH AND CROSS LS AND PUSH INTO ONTARIO
WEDNESDAY AFTERNOON/EVENING...WHICH WILL FINALLY PUSH THE TROUGH SE
OF THE AREA. HIGH PRESSURE WILL THEN SLOWLY BUILD IN AND LINGER
THURSDAY THROUGH THE START OF THE UPCOMING WEEKEND. WSW GUSTS MAY
INCREASE AGAIN TO NEAR 25-30KTS THURSDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KF
AVIATION...KC
MARINE...KF
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1223 AM CDT SUN JUN 17 2012
.SHORT TERM...
ISSUED AT 338 PM CDT SAT JUN 16 2012
(TONIGHT)
MAIN FOCUS TONIGHT WILL BE ON THE THREAT OF THUNDERSTORMS. THE
COMBINATION OF GOOD HEATING TODAY AND DEEPER MOISTURE RESULTED IN
VERY UNSTABLE CONDITIONS ACROSS MUCH OF THE CWA BY NOON. ISOLATED
SHOWERS AND THUNDERSTORMS DEVELOPED ACROSS PARTS OF EASTERN MO INTO
SOUTHWEST ILLINOIS AS AN EASTWARD PROPAGATING GRAVITY WAVE
INTERACTED WITH THIS AIR MASS PROVIDING WEAK ASCENT. COVERAGE OF
THESE STORMS HAS LARGELY DIMINISHED AS THE ASCENT HAS WEAKENED WITH
THE PASSAGE OF THE WAVE AND ALSO IN RESPONSE TO LESSER INSTABILITY
RESULTING FROM A MIXING IN THE DEEPENING BOUNDARY LAYER. THE
ATTENTION FOR THE REMAINDER OF THE AFTERNOON AND TONIGHT WILL TURN
TO THE REMNANT MCV NOW CENTERED IN NW MO AND APPROACHING COLD FRONT.
ENHANCED MESOSCALE LIFT ASSOCIATED WITH THE MCV HAS PRODUCED A GOOD
THUNDERSTORM CLUSTER ALONG THE SW IA/NW MO BORDER WITH MORE ISOLATED
COVERAGE SOUTHWARD. THIS FEATURE IS FORECAST TO TRACK EASTWARD THIS
EVENING AHEAD OF THE ENCROACHING COLD FRONT AND INTO NRN IL BY
MIDNIGHT. LIFT ASSOCIATED WITH IT AND A VEERING SWLY LLJ OF 25-35
KTS IS EXPECTED TO PROVIDE CONTINUED SUPPORT FOR THUNDERSTORMS
ACROSS NORTHERN MO INTO WEST CENTRAL IL THIS EVENING. THE MAIN
QUESTION IS HOW FAR SOUTH THE THUNDERSTORMS WILL MOVE. VIRTUALLY ALL
THE MODEL QPFS HAVE A GOOD SWATH OF MEASURABLE PRECIPITATION
TRANSLATING SOUTHWARD THROUGH THE NIGHT TO AT LEAST I-70. THE
CONVECTION ALLOWING MODELS AND ESPECIALLY RECENT RUNS OF THE HRRR
SUGGEST THERE WILL BE ADDITIONAL CONVECTION DEVELOPING FROM THE
AGITATED CU FIELD NOW EXTENDING FROM CHILLICOTHE TOWARDS EMPORIA KS
AND THIS ALONG WITH THE CLUSTER FURTHER NORTH WILL ORGANIZE INTO A
MCS THAT TRACKS SEWD. WHETHER IT IS A COMBINATION OF CONVECTION
ASSOCIATED WITH THE MCV AND CONVECTIVE OUTFLOWS OR LIFT AHEAD OF THE
FRONT ITSELF...IT IS HARD TO ARGUE AGAINST BRINGING LIKELY POPS DOWN
TO AROUND I-70.
GLASS
&&
.LONG TERM...
ISSUED AT 306 PM CDT SAT JUN 16 2012
(SUNDAY THROUGH SATURDAY)
SUNDAY`S WEATHER WILL DEPEND HEAVILY ON HOW CONVECTION DEVELOPS AND
MOVES TONIGHT AND HOW FAR SOUTH THE FRONT GETS ON SUNDAY. CURRENT
THINKING IS THAT THE FRONT WILL WASH OUT NEAR OR JUST NORTH OF THE
I-70 CORRIDOR. NAM/GFS/LOCAL WRF/SREF HAVE SOME EXTENT OF LINGERING
PRECIP DURING THE MORNING HOURS DOWN ACROSS SOUTHEAST MISSOURI AND
SOUTHERN ILLINOIS. THIS DOESN`T SEEM UNREASONABLE GIVEN THE
REMAINING SHORTWAVE ENERGY RIPPLING ALONG ALOFT DURING THE MORNING
AND THE RESIDUAL MOISTURE CONVERGENCE ON THE LOW LEVEL JET. HOWEVER
DISCRETE CONVECTIVE MODELS SUCH AS THE HRRR AND 4KM NCEP WRF LOOK
PRETTY DRY AFTER THE MCS LOSES STEAM LATE TONIGHT...THEN THE 4KM WRF
FIRES PRECIP DOWN OVER THE OZARKS DURING THE LATE AFTERNOON.
REGARDLESS...THINK THE BEST I CAN DO IS CHANCE POPS FOR
SUNDAY...UNSURE OF TIMING OR COVERAGE...BUT THERE IS CERTAINLY THE
POTENTIAL FOR PRECIP. SUNDAY NIGHT THE LOW LEVEL JET RAMPS UP AND
THE FRONT MOVES BACK NORTH. MODELS ARE SHOWING LIGHT QPF ON THE
NOSE OF THE WARM AIR ON AN AREA OF DECENT 850MB MOISTURE CONVERGENCE
OVER NORTHEAST MO/WEST CENTRAL IL DURING THE EVENING...SO HAVE
BUMPED UP TO CHANCE IN THOSE AREAS.
CONTINUING HOT AND DRY FORECAST FOR MONDAY AT LEAST THROUGH
WEDNESDAY. STRONG UPPER LEVEL HIGH BUILDS BACK INTO THE TENNESSEE
VALLEY WHICH SHOULD KEEP US STUCK IN SOUTHWEST FLOW. LOW TO MID 90S
DURING THE DAY AND LOW TO MID 70S AT NIGHT. SHOULD FEEL LIKE
SUMMER. MEDIUM RANGE MODELS ARE ADVERTISING A PATTERN SHIFT TOWARD
THE END OF THE WEEK WITH THE RIDGE TO OUR EAST BREAKING DOWN AND A
FROPA LATE THURSDAY OR FRIDAY. SHOULD BRING US COOLER TEMPERATURES
INTO NEXT WEEKEND AND A CHANCE FOR RAIN THURSDAY NIGHT AND FRIDAY.
CARNEY
&&
.AVIATION...
ISSUED AT 1211 AM CDT SUN JUN 17 2012
DECAYING LINE OF THUNDERSTORMS WAS MOVING THROUGH THE METRO AREA
TERMINALS AT TAF ISSUANCE. TSRA SHOULD PERSIST AT KSUS/KCPS FOR A
COUPLE OF HOURS BEFORE PCPN MOVES SOUTHEAST OF THE TERMINALS.
THERE MAY BE A BRIEF PD OF RADIATION FOG OR LOW STRATUS IN AREAS
THAT EXPERIENCE CLEARING AFTER THE RAIN ENDS. CDFNT OVER IA IS
EXPECTED TO DROP SWD TOWARDS UIN THEN LIFT NWD AGAIN. WINDS WILL
GENERALLY REMAIN WLY THEN BECOMING SLY AT ALL TAF SITES.
SPECIFICS FOR KSTL...DECAYING LINE OF THUNDERSTORMS SHOULD MOVE
THROUGH KSTL WITHIN THE NEXT HOUR OR SO. THERE MAY BE A BRIEF PD
OF RADIATION FOG OR LOW STRATUS IF CLOUDS CLEAR OUT BEFORE
SUNRISE. CDFNT OVER IA IS NO LONGER EXPECTED TO REACH KSTL
THEREFORE WLY WINDS WILL GRADUALLY TURN SWLY TO SLY THROUGH THE
PD.
KANOFSKY
&&
.PRELIMINARY POINT TEMPS/POPS...
ST LOUIS 73 95 75 95 / 30 5 5 5
QUINCY 70 93 73 93 / 30 5 5 5
COLUMBIA 70 93 72 93 / 20 5 5 5
JEFFERSON CITY 71 93 73 94 / 10 5 5 5
SALEM 71 92 73 93 / 20 5 5 5
FARMINGTON 68 91 71 92 / 10 5 5 5
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1226 AM CDT SUN JUN 17 2012
.AVIATION...06Z TAF. QUIET WEATHER EXPECTED FOR THIS TAF
PERIOD...AND KEPT CONDITIONS VFR...THOUGH WILL NEED TO KEEP AN EYE
OUT FOR ANY PATCHY FOG THAT MAY DEVELOP EARLY THIS MORNING. AT
THIS POINT NOT CONFIDENT ENOUGH IN IT HAPPENING TO PUT IT IN THE
TAF. SURFACE HIGH PRESSURE WILL REMAIN IN THE AREA...KEEPING WINDS
ON THE LIGHT SIDE THIS MORNING. DURING THE DAYTIME HOURS...ESP
STARTING NEAR MIDDAY...BETWEEN A TIGHTENING PRESSURE GRADIENT
DEVELOPING AS LOW PRESSURE MOVES INTO WRN SD/NEB AND INCREASED
MIXING POTENTIAL...EXPECTING WIND SPEEDS TO INCREASE UP TOWARD 20
MPH...WITH HIGHER GUSTS. THE GUSTY CONDITIONS LOOK TO CONTINUE ON
THROUGH THE REMAINDER OF THE TAF PERIOD. CURRENT WINDS ARE MORE
VARIABLE...BUT WILL GRADUALLY BECOME SOUTHEASTERLY THEN SOUTHERLY
BY MID/LATE MORNING.
&&
.PREV DISCUSSION... /ISSUED 917 PM CDT SAT JUN 16 2012/
UPDATE...JUST COMPLETED UPDATE ADDRESSING THE REST OF TONIGHT.
ONLY CHANGE OF NOTE WAS TO PULL THUNDERSTORM CHANCES FROM THE
MAJORITY OF THE CWA THAT STILL HAD THEM THIS EVENING...BUT ALSO
ADDED A TOKEN 20 POP THROUGH THE OVERNIGHT HOURS TO THE BOTTOM ROW
OF 3 COUNTIES IN NORTH CENTRAL KANSAS. STRONGLY CONSIDERED LEAVING
ALL AREAS STORM-FREE...BUT WITH THE 23Z HRRR STUBBORNLY INSISTING
THAT SOME CONVECTION COULD BRUSH NORTHERN KS OVERNIGHT...OPTED TO
PLAY IT SAFE IN THE FAR SOUTH. OTHERWISE...00Z NAM JUST COMING
KEEPS THE ENTIRE CWA DRY OVERNIGHT...WITH ANY KS CONVECTION
REMAINING WELL SOUTH OF I-70. UNLIKE LAST NIGHT...THE ONGOING
EVENING STORM CLUSTERS/MCS ACTIVITY ARE FOCUSED ACROSS SOUTHEAST
CO INSTEAD OF NORTHEAST CO/NORTHWEST KS...AND THUS THE ODDS OF
ANYTHING TRACKING DUE EAST INTO THE CWA ARE QUITE SMALL. AS FOR
THE ODDS OF ISOLATED ACTIVITY DEVELOPING OVERHEAD...THIS SEEMS
LIKE A LONG SHOT AS WELL...WITH NAM FORECAST SOUNDINGS SHOWING A
PRETTY STOUT CAP EVEN TO ELEVATED PARCELS IN THE 850-700MB LAYER.
ALL THAT BEING SAID...WITH AT LEAST A WEAK LOW LEVEL JET GRADUALLY
VEERING INTO THE CWA AS THE NIGHT WEARS ON...AND HINTS OF SOME
THETA-E ADVECTION AT 700MB..JUST CAN/T COMPLETELY DISCOUNT THE
POSSIBILITY THAT A FEW SHOWERS/WEAK STORMS COULD FLARE UP INTO KS
ZONES TO THE NORTH OF THE MORE LIKELY ACTIVITY ACROSS SOUTHERN
PORTIONS OF THE STATE. TURNING TO OTHER ELEMENTS...MADE NO CHANGE
WHATSOEVER TO OVERNIGHT LOW TEMPS...WITH UPPER 50S NORTH TO MID
60S SOUTH STILL ON TRACK. FINALLY...PONDERED THE POSSIBILITY OF
ADDING PATCHY FOG MENTION OVERNIGHT...BUT UNLESS DEWPOINTS STAY UP
HIGHER THAN CURRENTLY THOUGHT...SUSPECT ANY VISIBILITY
RESTRICTIONS SHOULD ONLY AMOUNT TO A LIGHT HAZE ON THE ORDER OF
4-6 MILES...AND PROBABLY NOT WORTHY OF A FORMAL MENTION.
PREV DISCUSSION... /ISSUED 340 PM CDT SAT JUN 16 2012/
SHORT TERM...THIS EVENING THROUGH SUNDAY. THERE WILL BE A SLIGHT
CHANCE OF A FEW SHOWERS AND THUNDERSTORMS AROUND LATE THIS AFTERNOON
INTO EARLY THIS EVENING...PRIMARILY SOUTHEAST OF A
FULLERTON...KEARNEY...ELWOOD LINE. ANY THUNDERSTORMS WILL BE RATHER
ISOLATED WITH MOST AREAS REMAINING DRY. SUNDAY WILL BE HOT AND DRY.
THIS EVENING INTO TONIGHT...THE COLD FRONT THAT TRACKED SOUTH
THROUGH OUR FORECAST AREA TODAY WILL WASHOUT ACROSS SOUTHERN KANSAS
TONIGHT. IT COULD STILL PROVE TO BE ENOUGH OF A FOCUSING MECHANISM
TO KICK OFF A FEW SHOWERS AND THUNDERSTORMS OVER PRIMARILY SOUTHERN
KANSAS THIS EVENING...WITH JUST THE SLIGHTEST CHANCE OF AN ISOLATED
THUNDERSTORM AS FAR NORTH AS OUR SOUTHERN CWA. ANY STORMS IN OUR
AREA WOULD PRIMARILY BE DUE TO AFTERNOON HEATING AND SHOULD DIE OUT
BY EARLY EVENING WITH THE LOSS OF THAT HEATING. MOST AREAS WILL
REMAIN DRY.
SUNDAY...THE FRONT WILL QUICKLY PUSH BACK NORTH AS A WARM FRONT ON
SUNDAY WITH SOUTH WINDS AND A VERY WARM ELEVATED MIXED LAYER
OVERSPREADING THE REGION. HIGH TEMPERATURES WILL EASILY CLIMB BACK
INTO THE 90S WITH MID TO UPPER 90S POSSIBLE ACROSS NORTHERN KANSAS.
THE WARM ELEVATED MIXED LAYER SHOULD KEEP THE ENVIRONMENT VERY
CAPPED. AN ISOLATED THUNDERSTORM COULD POSSIBLY OVERCOME THE CAP
NORTH OF HIGHWAY 92...BUT THIS POSSIBILITY IS LOW AND THE COVERAGE
AREA OF ANY CONVECTION WOULD BE VERY LIMITED. CONSEQUENTLY WE WILL
CONTINUE TO GO WITH A DRY FORECAST WITH RAIN CHANCES ONLY AT 10
PERCENT OR LESS.
LONG TERM...00Z MONDAY THROUGH FRIDAY. CONCERNS IN THIS TIME FRAME
INCLUDE HOT TEMPERATURES EARLY IN THE WORK WEEK AND THEN CHANCE OF
RAIN TUESDAY NIGHT INTO THURSDAY NIGHT OR FRIDAY.
EXTENDED MODELS IN PRETTY GOOD AGREEMENT WITH THE BASIC PATTERN OF
STARTING OUT IN ZONAL FLOW WITH THE BEST JET ACTION ACROSS THE
NORTHERN PLAINS AT 00Z MONDAY...AND THEN TRANSITIONING TO MORE OF A
BROAD TROUGH ACROSS THE NORTHERN ROCKIES/NORTHERN PLAINS WITH
RIDGING ACROSS THE EASTERN U.S. BY TUESDAY NIGHT...AND THEN THE
TROUGH WILL WORK EAST AND EVENTUALLY WE SEE PRETTY GOOD RIDGING
BUILDING INTO THE HIGH PLAINS BY NEXT FRIDAY/INTO THE WEEKEND.
STARTING OUT SUNDAY EVENING...LOOKS LIKE A WARM FRONT SHOULD HAVE
WORKED WELL NORTH OF THE CWA WITH A DRY LINE TO THE WEST. BETTER MID
LEVEL FORCING SHOULD ALSO BE NORTH OF THE AREA AND WARMER MID LEVEL
TEMPS WILL BE BUILDING IN FROM THE SOUTHWEST. WILL LEAVE FORECAST
DRY AS BETTER CHANCES APPEAR TO BE NORTH FOR REASONS MENTIONED
ABOVE.
MONDAY WILL BE DOWNRIGHT HOT WITH 850 PROGGED TEMPS ANYWHERE FROM
THE UPPER 20S TO LOWER 30S CELSIUS IN THE WESTERN PART OF THE CWA
DEPENDING ON WHICH MODEL ONE GOES WITH. NAM LOOKS TO BE THE WARMEST
OF THE MODELS AS IT BRINGS DRY LINE A LITTLE FURTHER EAST INTO OUR
CWA WHILE GFS JUST A BIT WEST OF THAT POSITION. THIS WOULD ALLOW THE
NAM TO PRODUCE SURFACE WINDS WITH MORE OF A SOUTHWEST COMPONENT
WHICH WOULD FAVOR PARTS OF THE CWA REACHING OR EXCEEDING THE CENTURY
MARK. WILL COMPARE THE LATEST EC MODEL RUN WHEN IT COMES IN. SHOULD
REMAIN DRY MONDAY NIGHT INTO TUESDAY WITH VERY WARM MID LEVEL TEMPS
OF 14 TO 17C AT 700 MB KEEPING THINGS CAPPED.
CHANCES OF RAIN THEN BEGIN TO INCREASE BY TUESDAY NIGHT AS SURFACE
FRONT PUSHES INTO THE NORTHWEST PART OF THE CWA. OUTSIDE CHANCE OF A
LATE AFTERNOON TSTM IN THE NW BUT WILL LEAVE MENTION OUT FOR NOW AS
WE SHOULD STILL BE CAPPED. WILL MOST LIKELY CONTINUE PREVIOUS
THINKING AND CONFINE RAIN CHANCES TO AREAS ALONG AND NORTH OF
HASTINGS FOR TUESDAY NIGHT.
APPEARS THAT FRONT SHOULD HANG UP SOMEWHERE ACROSS SOUTHERN NEB OR
ACROSS KANSAS FOR WEDNESDAY AND THURSDAY. EXACT LOCATION EACH DAY
WILL DICTATE PRECIPITATION REGION. WOULD THINK BETTER CHANCES SHOULD
BE AT NIGHT AS LOW LEVEL JET TRANSPORTS WARM AND MOIST AIR OVER THE
BOUNDARY. AS FAR AS SEVERE WEATHER IS CONCERNED...THERE ARE A FEW
PERIODS WHERE INSTABILITY IS RESPECTABLE AS SEEN ON EC CAPE
PROJECTIONS...BUT DEEP LAYER SHEAR VALUES LACKING DURING THE TUESDAY
THROUGH THURSDAY NIGHT TIME FRAME.
AS NOTED ABOVE...RIDGING IS PROGGED TO BUILD BACK IN STARTING
FRIDAY. OVERALL THIS SHOULD KEEP THINGS DRY INTO THE START OF THE
NEXT WORK WEEK AND THE HEAT WILL ALSO RETURN. IF THE RIDGE DOES
BUILD IN AS EXPECTED...IT SHOULD PUT US IN THE RING-OF-FIRE
SCENARIO...LEADING TO DRY WEATHER UNLESS SOMETHING CAN WORK DOWN
OVER THE TOP OF THE RIDGE FROM THE NW.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
AVIATION...ADO
UPDATE...PFANNKUCH
SHORT...WESELY
LONG...EWALD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
140 AM EDT SUN JUN 17 2012
.SYNOPSIS...
UNSEASONABLY COOL TEMPERATURES THIS WEEKEND WILL TRANSITION TO
MORE TYPICAL JUNE WARMTH THROUGH EARLY NEXT WEEK AS AN UPPER RIDGE
DEVELOPS OVER THE REGION. THE RIDGE WILL MAINTAIN GENERALLY DRY
CONDITIONS FOR MUCH OF THE FORECAST PERIOD. A COLD FRONT MAY
APPROACH THE AREA LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AS OF 11:00 PM SATURDAY...ABSOLUTELY NO CHANGES TO THE WEATHER
PICTURE OVER THE PAST FEW HOURS. SATELLITE LOOPS AND MODEL
GUIDANCE CONTINUE TO SHOW THAT PATCHY CIRRUS WILL STREAM SOUTH
ACROSS THE AREA OVERNIGHT. ANOTHER COOL AND DRY OVERNIGHT PERIOD.
PREVIOUS DISCUSSION FROM THIS AFTERNOON FOLLOWS:
THIS NORTHEAST FLOW WILL MAINTAIN RELATIVELY COOLER AND DRIER
WEATHER FOR THE MOST PART. LIMITED MOISTURE WILL CONTINUE TO
STREAM AROUND THE HIGH IN THE NORTHEAST FLOW. HRRR SHOWS A NICE
DEPICTION OF THIS MOISTURE IN TERMS OF CU DEVELOPMENT. VALUES OF
LESS THAN A HALF INCH INLAND WHERE CLEAR SKIES EXIST UP TO .75
INCHES IN PATCHES WHERE CU DEVELOPED CLOSER TO THE COAST. SEA
BREEZE PUSHED JUST FAR ENOUGH INLAND TO KEEP TIP OF CAPE FEAR
CLEAR OF ANY CLOUDS. SOUNDING DATA AND MOISTURE PROFILES SHOW
LAYER OF MOISTURE LOCKED IN BELOW INVERSION JUST UNDER 7K FT
DRYING OUT THROUGH THIS EVENING. HRRR SHOWS PCP WATER DOWN LESS
THAN A HALF INCH OVER AREA TONIGHT. ONCE THE CU DISSIPATE BY
EVENING...EXPECT CLEAR SKIES THROUGH MORNING.
COOL NORTHEAST FLOW AND SOME CAA WILL KEEP TEMPS BELOW NORMAL ONCE
AGAIN. AS THE GRADIENT WEAKENS TONIGHT AND THE ATMOSPHERE
DECOUPLES AFTER SUNSET...CALM AND CLEAR CONDITIONS WILL PRODUCE MORE
IDEAL RADIATIONAL COOLING. THEREFORE ANOTHER COOL NIGHT IS IN
STORE WITH TEMPS DOWN BELOW 60.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
AS OF 255 PM SATURDAY...A WARMING TREND WILL OCCUR IN THIS PERIOD
AS AN UPPER RIDGE BEGINS TO EXPAND OVER THE AREA COUPLED WITH
SURFACE HIGH PRESSURE MOVING OFFSHORE LATE SUNDAY. WITH LIGHT
WIND AND GENERALLY CLEAR SKIES...WE WILL SEE MINIMUM TEMPS BELOW
NORMAL FOR MIDDLE JUNE BOTH MON/TUE AT DAYBREAK...MAINLY LOW AND
MIDDLE 60S.
INTRODUCED A SLIGHT CHANCE OF A SHOWER OVER OUR FAR INTERIOR
MONDAY AFTERNOON AS WEAK SHORTWAVE ENERGY DROPS OVER TOP OF THE
UPPER RIDGE. MOISTURE ENHANCEMENT IS EVIDENT IN RH TIME-HEIGHT
PLOTS IN THE BOUNDARY LAYER UP TO 500 MB. CONCURRENTLY WE SHOULD
HAVE SOME FORM OF SEA BREEZE CONVERGENCE WELL INLAND TO GIVE US
A CRACK AT A BRIEF SHOWER OVER OUR NW ZONES 3PM-6PM MONDAY.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 255 PM SATURDAY...SURFACE HIGH PRESSURE COMBINED WITH UPPER
RIDGING CREATES SUMMER-LIKE WEATHER DURING THE WEEK WITH DRY AND
WARM CONDITIONS EXPECTED THROUGH FRIDAY. UPPER RIDGE AXIS SHIFTS
EAST ON TUESDAY...AND ALTHOUGH A WEAK SHORTWAVE WILL DROP SOUTH OVER
THE CAROLINAS DURING THE DAY...A DRY COLUMN AND SUBSIDENCE BENEATH
THE RIDGE WILL INHIBIT ANYTHING OTHER THAN SOME ENHANCED MID LEVEL
CLOUD COVER. 500MB RIDGE SHIFTS DIRECTLY OVERHEAD WED-FRI ALLOWING
TEMPS TO WARM TO ABOVE CLIMO THROUGH THE END OF THE WEEK WITH AMPLE
SUNSHINE. RIDGE THEN BEGINS TO BREAK DOWN AHEAD OF A SHORTWAVE WHICH
WILL TRY TO DRIVE A COLD FRONT THROUGH THE AREA LATE SATURDAY. THIS
IS FASTER THAN PREVIOUS MODELS...BUT RECOGNIZE THAT STRONG RIDGES
TEND TO DELAY COLD FRONTS SO CURRENT PROGS MAY BE TOO FAST TO BRING
THROUGH FRONT SATURDAY. COMBINE THIS WITH LACK OF SIGNIFICANT
FORCING AND WILL BUMP POP TO SCHC...BUT NOT HIGH ENOUGH TO MENTION
IN THE FORECAST 7 DAYS OUT.
TEMPS TUESDAY WILL BE RIGHT AROUND CLIMO BEFORE RISING THROUGH THE
REST OF THE WEEK. 850MB TEMPS RISE TO 18-20C BY FRIDAY...BUT
EASTERLY MID LEVEL FLOW WILL INHIBIT US FROM REALIZING THE FULL
POTENTIAL OF THIS WARMTH ALOFT UNTIL FRIDAY WHEN WINDS SHIFT TO THE
SW THROUGH THE COLUMN...AND FRIDAY LOOKS TO BE THE WARMEST DAY OF
THE PERIOD. STILL...TEMPS WILL BE ABOVE CLIMO WED-SAT...LOW 90S MOST
PLACES AWAY FROM THE BEACHES. MINS AT NIGHT WILL FALL ONLY TO THE
UPPER 60S WED NIGHT...AND AROUND 70 THE REST OF THE WEEK.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 06Z...EXPECT VFR TO PREVAIL THROUGH VALID TAF PERIOD. LIGHT
NORTHEAST WINDS WILL CONTINUE THROUGH THE OVERNIGHT HOURS WITH
NEARLY CLEAR SKIES. AFTER DAYBREAK...NORTHEAST WINDS WILL INCREASE
TO 10 TO 15 KTS AT ALL TERMINALS. A DEVELOPING RESULTANT WIND
BOUNDARY IN THE AFTERNOON WILL VEER WINDS TO THE EAST-SOUTHEAST AT
THE COASTAL TERMINALS. ANTICIPATE DIURNAL CU TO DEVELOP AGAIN
THROUGHOUT THE AFTN PERIOD AROUND 4KFT. FOR THE LATE EVENING INTO
THE OVERNIGHT HOURS...EAST-SOUTHEAST WINDS AT ALL TERMINALS WILL
BECOME LIGHT. DIURNALLY DRIVEN CU WILL DISSIPATE AT OR JUST AFTER
SUNSET.
EXTENDED OUTLOOK...VFR THROUGH THE FORECAST PERIOD. A SLIGHT
CHANCE OF SHOWERS TUESDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 11:00 PM SATURDAY...LATEST COASTAL AND BUOY OBS SHOW AN
UNEXPECTEDLY STRONG COLD SURGE MOVING ACROSS OUR NC WATERS...WITH
WINDS UP IN THE 20 KT RANGE ALONG THE COAST. SEAS HAVE KICKED UP
TO 4 TO 5 FT AS A RESULT. EXPECT THIS TO BE TEMPORARY AS OVERALL
GRADIENT RELAXES. HAVE ADDED EXERCISE CAUTION HEADLINES TO OUR NC
WATERS FOR THE NEAR TERM. PREVIOUS DISCUSSION FOLLOWS:
A CUTOFF LOW CLOSE TO THE BAHAMAS WILL MEANDER AROUND BUT THE HIGH
PRESSURE REACHING INTO LOCAL WATERS FROM THE NORTH WILL WEAKEN
THROUGH TONIGHT. THIS WILL ALLOW THE GRADIENT TO RELAX FURTHER AND
EXPECT SEAS TO RESPOND BY SUBSIDING THROUGH SUN MORNING. LATEST
OBS SHOWING SEAS UNDER 6 FT IN LOCAL WATERS. THEREFORE ALL SMALL
CRAFT ADVISORIES WILL BE DISCONTINUED WITH AFTERNOON PACKAGE.
PERSISTENT NORTHEAST WINDS AROUND 15 KTS WILL DIMINISH THROUGH
TONIGHT DOWN TO 10 TO 15 KTS BY MORNING. THIS WILL ALLOW SEAS TO
COME DOWN FROM AROUND 5 FT IN OUTER WATERS TO 2 TO 4 FT BY MORNING
ACROSS MOST WATERS. THE SEAS WILL REMAIN A MIX OF NE SWELL WITH
NEARLY A 9 SEC PERIOD AND LOCALLY WIND DRIVEN SHORTER PERIOD
SWELL.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 255 PM SATURDAY...SUNDAY AFTERNOON AND EVENING WILL MARK A
TRANSITION IN WIND DIRECTION AS A SURFACE HIGH PRESENTLY OVER
LAND...SLIPS OFFSHORE AND BRINGS WINDS AROUND WITH A SOUTHERLY
COMPONENT. THIS WILL LIKELY OCCUR SUNDAY AFTERNOON AS THE SEA
BREEZE CIRCULATION HASTENS THE TRANSITION...S-SE WINDS 10-15 KT
SUNDAY AFTERNOON...EASING TO S-SW 5 KT OVERNIGHT SUNDAY. SOUTH
WINDS MONDAY AS THE HIGH HOLDS JUST OFFSHORE OF OUR COAST.
WAVE DIRECTION BOTH SUNDAY AND MONDAY WILL HOLD FROM AN EASTERLY
DIRECTION...WITH GRADUALLY DECREASING WAVE HEIGHTS SUNDAY INTO
MONDAY. SOME NEAR SHORE CHOPPINESS WILL OCCUR SUNDAY AND MONDAY
AFTERNOON...AS THE SEA BREEZE ENHANCES WIND SPEEDS SEVERAL KTS.
LONG TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 255 PM SATURDAY...HIGH PRESSURE EXTENDING ACROSS THE WATERS
THROUGH THE LONG TERM CREATES LIGHT WINDS AND INCREASING SE SWELL.
WINDS OF AROUND 10 KTS WILL PERSIST THROUGH THE PERIOD...AND WILL
HAVE A PREDOMINANT SOUTHERLY COMPONENT WITH ONLY MINOR TEMPORAL
FLUCTUATIONS TO SE OR SW. SINCE THESE WINDS WILL BE LIGHT...THE WAVE
SPECTRUM WILL BE ALMOST ENTIRELY SWELL DOMINATED. A 2FT/8SEC E/SE
SWELL WILL START THE PERIOD...BUILDING TO A 3FT/8SEC SE SWELL AS
RETURN FLOW CONTINUES AROUND HIGH PRESSURE. SEAS WILL BE ONLY 1-2
FT THROUGH WEDNESDAY...BUILDING TO 2-3 FT LATE THURSDAY DUE TO
THE INCREASED SWELL AMPLITUDE.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MJC
NEAR TERM...REK/RGZ
SHORT TERM...MJC
LONG TERM...JDW
AVIATION...DCH/SGL
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
109 AM EDT SAT JUN 16 2012
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN NEAR THE ATLANTIC COAST THROUGH THE
WEEKEND. AN UPPER LEVEL DISTURBANCE MAY MOVE INTO NW OHIO BY
SUNDAY MORNING. THIS WILL BE FOLLOWED BY A WEAKENING COLD FRONT
THAT WILL STALL OVER CENTRAL OHIO. THE FRONT WILL DISSIPATE BY
TUESDAY AS HIGH PRESSURE STRENGTHENS OVER THE MIDDLE ATLANTIC.
&&
.NEAR TERM /THROUGH SUNDAY/...
MADE MINOR ADJUSTMENTS TO TIMING OF HOURLY POPS AND WX THROUGH THE
OVERNIGHT BASED ON RADAR TRENDS AND RECENT HRRR MODEL RUNS.
CONVECTION THAT MOVED INTO NW OH EARLIER THIS EVENING QUICKLY
DETERIORATED...AND FOCUS WILL BE ON SHOWERS AND THUNDERSTORMS OVER
IL. EXPECTING THIS AREA OF SHRA/TS TO MOVE EAST OVERNIGHT...BUT
THEN ADDITIONAL DEVELOPMENT AHEAD OF THIS INITIAL CLUSTER OF
ACTIVITY WITH SHRA/TS MOVING INTO WRN ZONES TOL-FDY AROUND
07-09Z...THEN CONTINUE TO GRADUALLY MOVE EAST TOWARD CLE-MFD BY
12Z. ZONES INDICATING MAINLY LIKELY WORDING GIVEN HIGH POPS LATE
IN THE OVERNIGHT PERIOD ESPECIALLY EAST OF SANDUSKY-MARION LINE.
MADE MINOR TEMP ADJUSTMENTS ON LOWS WITH MAINLY MID 60S ACROSS THE
EASTERN HALF OF THE AREA WITH LOWER 60S FOR NW PA. PREVIOUS
DISCUSSION BELOW.
OVERNIGHT HOWEVER MODELS CONTINUE TO SHOW COLD FRONT APPROACHING
FROM THE NORTHWEST WITH A SHORT WAVE AND FURTHER INCREASING
MOISTURE. BY MORNING EXPECT SHOWERS AND THUNDERSTORMS TO HAVE
REACHED INTO NWRN OHIO SO WILL GO WITH LIKELY POPS FAR
NORTHWEST...AND CHANCE/SLIGHT CHANCE ELSEWHERE.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
SUNDAY CONTINUES TO LOOK LIKE SHOWERS AND THUNDERSTORMS WILL BE
LIKELY ALTHOUGH DO NOT EXPECT A COMPLETE WASHOUT OF THE DAY WITH
AT LEAST PARTLY SUNNY SKIES BETWEEN THUNDERSTORMS. WILL GO WITH
LIKELY POPS ALL COUNTIES. TIMING APPEARS TO FAVOR THE MORNING WEST
AND AFTERNOON EAST BASED ON FRONTAL POSITION AND PROGGED MOISTURE.
BY 00Z MONDAY DEEPER MOISTURE WILL BE EAST OF THE AREA. WILL CARRY
A CHANCE INTO THE FIRST HALF OF THE NIGHT EAST HALF BUT AFTER
MIDNIGHT WILL DROP TO A SLIGHT CHANCE GIVEN LACK OF FORCING.
MONDAY INTO TUESDAY THE UPPER RIDGE BUILDS BACK ACROSS THE OHIO
VALLEY. AFTERNOON CAPES BOTH DAYS APPROACH 1500 J/KG ON THE NAM12
THINKING THAT THE UPPER RIDGE WILL SUPPRESS CONVECTION FOR THE MOST
PART. WILL HAVE LOW CHANCE POPS AND SLIGHT CHANCE POPS FOR MONDAY
BUT WILL KEEP DRY TUESDAY. TEMPS NEAR 90 BOTH MONDAY AND TUESDAY
SHOULD BE COMMON.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
A STALLED UPPER RIDGE OVER THE EAST THIRD OF THE COUNTRY WILL
PROVIDE DRY AND HOT CONDITIONS FOR THE AREA THROUGH MID WEEK. MODELS
A LITTLE FASTER WITH THE NEXT WEAK FRONT MOVING IT THROUGH THURSDAY
NIGHT INTO FRIDAY MORNING. WENT WITH THE GFS WHICH WAS SLIGHTLY
SLOWER THAN THE CURRENT ECMWF.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
TSRA WILL BE ISSUE AFFECTING AVIATION NEXT 24 HOURS. EXPECTING FIRST
BAND OF POSSIBLE CONVECTION TO PROGRESS EAST ACROSS MOST OF AREA
THROUGH ABOUT 15Z. QUESTION IS HOW MUCH COVERAGE WILL OCCUR WITH THE
FIRST BAND. SHORT TERM MODELS DIFFER SOME BUT IN GENERAL DISSIPATE
CONVECTION OVER INDIANA THEN TRY AND REDEVELOP SOME SCT ACTIVITY IN
WESTERN OH ABOUT 08 TO 09Z AND PROGRESS THIS EAST. NOT CONFIDENT
ENOUGH AT THIS POINT TO USE TEMPO SO WILL USE VCTS OR VCSH.
EXPECT MORE CONVECTION TO DEVELOP WITH DYING COLD FRONT LATER TODAY
AS AIRMASS HEATS UP. WITHOUT SHARP FRONT TO PROVIDE NARROW FOCUS TO
CONCENTRATE CONVECTION DON`T LIKE IDEA OF CARRYING TEMPO THIS FAR
OUT. DO FEEL THAT BULK OF ACTIVITY IN WEST AND CENTRAL AREAS WILL
OCCUR BETWEEN 18 AND 23Z AND 19 TO 02Z IN THE EAST.
.OUTLOOK...NON VFR POSSIBLE MAINLY IN WIDELY SCT CONVECTION MONDAY.
&&
.MARINE...
SOUTH FLOW OVER THE LAKE WILL INCREASE TO 10 TO 20 KNOTS SUNDAY THEN
VEER A LITTLE MORE TOWARD SOUTHWEST SUNDAY NIGHT AS A WEAK COLD
FRONT MOVES ACROSS THE LAKE. A SOUTH TO SOUTHWEST FLOW WILL REMAIN
OVER THE LAKE THROUGH MID WEEK AS RIDGE OF HIGH PRESSURE REMAINS
OVER THE LAKE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TK
NEAR TERM...ABE/TK
SHORT TERM...TK
LONG TERM...DJB
AVIATION...ADAMS
MARINE...DJB
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1236 AM CDT SUN JUN 17 2012
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND SUNDAY.
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A WEAK
MID-LEVEL CIRCULATION MOVING NORTHEAST INTO CENTRAL WISCONSIN EARLY
THIS AFTERNOON. A PROMINENT BAND OF SHOWERS AND EMBEDDED
THUNDERSTORMS DEVELOPED AHEAD OF THIS CIRCULATION EARLIER TODAY WHICH
IS NOW MOVING ACROSS NORTHERN AND NORTH-EAST WISCONSIN. MORE
SCATTERED SHOWER ACTIVITY EXISTS OVER WESTERN...CENTRAL...AND
SOUTHERN WISCONSIN. FARTHER UPSTREAM...A STRONG SHORTWAVE OVER THE
DAKOTAS IS DRIVING A COLD FRONT EAST OVER MINNESOTA. STORMS HAVE
STARTED TO DEVELOP ALONG THE FRONT BUT INSTABILITY IS LACKING SO
FAR. THERE IS SOME CLEARING OVER EASTERN MINNESOTA SO SOME
POTENTIAL FOR FURTHER DESTABILIZATION...BUT TEMPS ARE ONLY THE MID
TO UPPER 70S...AND ARE COOLER OVER WISCONSIN SO SEVERE WEATHER IS
NOT EXPECTED TO DEVELOP. AS THESE TWO SYSTEMS MOVE EAST...PRECIP
CHANCES ARE THE MAIN FORECAST CONCERN.
TONIGHT...WEAK SHORTWAVE ACTIVITY THAT IS PASSING ACROSS WISCONSIN
THIS AFTERNOON WILL EXIT TO THE NORTHEAST THIS EVENING. TRACKING
THE CENTER OF THIS CIRCULATION TAKES IT NORTH AND WEST OF THE FOX
VALLEY...SO WILL PLACE THE HIGHEST POPS NORTH OF THIS LINE. CAN
STILL EXPECT MORE SPOTTY ACTIVITY TO THE SOUTH THROUGH EARLY IN THE
EVENING. STRONGER FORCING WILL ARRIVE LATE THIS EVENING INTO THE OVERNIGHT
WHEN A SHORTWAVE OVER THE DAKOTAS DRIVES A COLD FRONT ACROSS THE
STATE. WITH THE WIDESPREAD CLOUD COVER AND SHOWER
ACTIVITY...INSTABILITY HAS BEEN HELD IN CHECK. STILL THOUGH...THE
MODELS ARE SPITTING OUT 300-500 J/KG OF ELEVATED CAPE THIS EVENING
AHEAD OF THE FRONT. BUT WONDER IF WE ARE GOING TO SEE A NORTHERN
WISCONSIN SPLIT...WHERE SHOWERS AND STORMS MOVE TO THE NORTH AND
SOUTH OF THE REGION. WILL KEEP LIKELY POPS OVER NORTH-CENTRAL
WISCONSIN NORTH OF THE MID-LEVEL CIRCULATION AND CHANCE POPS TO THE
SOUTH. IF SOME SORT OF BROKEN LINE OF SHOWERS AND STORMS DOES
DEVELOP THIS AFTERNOON ALONG THE FRONT...FIGURE IT WILL BE WEAKENING
AS MOVES ACROSS THE FORECAST AREA LATE THIS EVENING SINCE
INSTABILITY WILL BE DIMINISHING. THE FRONT WILL BE EXITING THE AREA
BY 09Z AND WILL SEE CLEARING SKIES BEHIND THE FRONT.
SUNDAY...WEAK HIGH PRESSURE WILL MOVE INTO THE REGION ON SUNDAY.
WILL LIKELY SEE DIURNAL CU DEVELOP OVER N-C WISCONSIN WHERE COOLER
TEMPS WILL RESIDE AT 850MB AND THERE IS ENHANCED RH. LOCATIONS TO
THE SOUTH WILL SEE A MOSTLY SUNNY TO PARTLY CLOUDY DAY. HIGHS
RANGING FROM THE UPPER 70S NORTH TO MID 80S SOUTH.
.LONG TERM...SUNDAY NIGHT THROUGH NEXT SATURDAY.
TEMPERATURES SHOULD REMAIN ABOVE NORMAL THROUGH THE MIDDLE OF
NEXT WEEK WITH AN UPPER LEVEL RIDGE ACROSS THE EASTERN CONUS.
MODELS DIFFERED IN HOW QUICKLY THEY TOOK THE CENTRAL CONUS TROUGH
EAST OF THE AREA...RESULTING IN A PERIOD OF DRIER WEATHER.
STORMS ARE EXPECTED TO MOVE INTO CENTRAL WISCONSIN ON SUNDAY
NIGHT...WHILE THE EAST REMAINS DRY. A WARM FRONT WILL MOVE INTO
CENTRAL AND SOUTHERN WISCONSIN ON MONDAY...BRINGING SHOWERS AND
THUNDERSTORMS TO THE AREA. SOME STORMS COULD BECOME SEVERE WITH PLENTY
OF WARM AND MOIST AIR IN PLACE. HEAVY RAINFALL IS ALSO POSSIBLE.
MODELS INDICATED A WEST TO EAST AXIS OF MAX QPF MOVING NORTH ON
TUESDAY INTO TUESDAY NIGHT. HEAVY RAINFALL REMAINS POSSIBLE DURING
THE PERIOD...BUT THE EXACT LOCATION OF THE STORMS IS A BIT UNCERTAIN.
TIMING DIFFERENCES AROUND THE MIDDLE OF THE WEEK WILL RESULT IN A
MORE UNCERTAIN FORECAST...BUT THE LATTER HALF OF THE WEEK SHOULD
GENERALLY BE DRY.
&&
.AVIATION...A COLD FRONT WILL MOVE ACROSS THE AREA OVERNIGHT WITH
WEAK HIGH PRESSURE BUILDING INTO THE STATE FOR SUNDAY. SCATTERED
SHOWERS WITH MFR CIGS WILL CONTINUE TO PASS OVER EAST CENTRAL
WISCONSIN EARLY THIS MORNING FOLLOWED WITH VFR CONDITIONS SUNDAY.
TDH
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
1150 AM EDT SUN JUN 17 2012
.UPDATE (REST OF TODAY AND TONIGHT)...
15Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS A SIMILAR PICTURE TO THE
ONE FROM 24 HOURS AGO. THE FORECAST AREA REMAINS IN BETWEEN AN UPPER
LEVEL RIDGE ACROSS THE WESTERN GULF OF MEXICO/LOWER MS VALLEY AND A
LARGE ATLANTIC TROUGH/CLOSED LOW SPINNING SEVERAL HUNDRED MILES
EAST OF THE CAROLINA COAST. OUR POSITION ON THE WESTERN PERIPHERY OF
THIS TROUGH IS PROVIDING A DEEP LAYER NORTHERLY FLOW OVER THE
PENINSULA. ALTHOUGH SOME SLIGHT MOISTURE ADVECTION IN THE UPPER
LEVELS HAS BEEN NOTED IN WV THIS MORNING WITHIN THIS NORTHERLY
FLOW...THE OVERALL COLUMN REMAINS QUITE DRY. 12Z KTBW SOUNDING
PROFILE MEASURED A PW VALUE OF AROUND AN INCH. THIS VALUE IS ONLY
AROUND 65% OF CLIMATOLOGY FOR MID JUNE. THE DRIER AIR IS PROVIDING
FOR AN OVERALL HOSTILE ENVIRONMENT FOR DEEP CONVECTION WITH
700-500MB THETA-E VALUES MEASURED BETWEEN 316-319K. TYPICAL VALUES
FOR THIS TIME OF YEAR TO SUPPORT SUSTAINED DEEP CONVECTION RUN
BETWEEN 323-329K.
AT THE SURFACE...1022MB HIGH PRESSURE CENTERED OVER THE CAROLINAS
CONTINUES TO RIDGE SOUTHWARD OVER THE FL PENINSULA AND EASTERN GULF.
THE GRADIENT IS RATHER TIGHT RESULTING IN A BREEZY E/NE FLOW. THIS
GRADIENT IS EXPECTED TO WEAKEN SLIGHTLY THIS AFTERNOON...WHICH MAY
ALLOW FOR SOME FEEBLE SEA-BREEZE DEVELOPMENT. HOWEVER...THE SYNOPTIC
FLOW ONLY 1500-2000 KFT ABOVE THE SURFACE HOLDS EAST AT 10-15 KTS
THROUGH THE AFTERNOON. THIS SHOULD BE ENOUGH TO KEEP ANY WEAK
SEA-BREEZE CIRCULATION PINNED AT THE BEACHES OR EVEN SLIGHTLY
OFFSHORE.
WITH LITTLE TO NO INLAND PENETRATION OF ANY FEEBLE SEA-BREEZE...
COMBINED WITH THE MID-LEVEL ENVIRONMENT...CONVECTIVE COVERAGE THIS
AFTERNOON SHOULD BE BELOW CLIMATOLOGY. STILL CAN`T RULE OUT A FEW
ISOLATED CELLS DEVELOPING...ESPECIALLY CLOSE TO THE COAST WHERE SOME
LOW LEVEL FOCUS FOR UPDRAFTS MAY BECOME ESTABLISHED IN SEVERAL
HOURS. SIMILAR TO SATURDAY...ANY CELLS THAT DO TRY TO DEVELOP WILL
ENCOUNTER AND ENTRAIN THE UNFAVORABLE MID-LEVEL AIR...AND LIKELY
DECAY RAPIDLY. CURRENTLY HAVE A SLIGHT CHANCE 15-20% POP IN THE
GRIDS STARTING AFTER 18Z...AND FEEL THIS SHOULD HANDLE THE SITUATION.
ANY ISOLATED STORMS EARLY THIS EVENING NEAR THE COAST SHOULD PUSH
OFFSHORE WITH THE SYNOPTIC FLOW AFTER 00-02Z. THE REST OF THE
OVERNIGHT LOOKS DRY AND SEASONABLE COOL. ONCE AGAIN MANY INLAND
SPOTS WILL BOTTOM OUT IN THE 60S BY SUNRISE MONDAY MORNING. HAVE A
PLEASANT SUNDAY AFTERNOON!
&&
.AVIATION...
MAINLY VFR NEXT 24 HOURS. EASTERLY SURGE COULD BRING GUSTY WINDS TO
TERMINALS DURING THE AFTERNOON AND EVENING HOURS. MODERATE EASTERLY
WIND FLOW SHOULD PRECLUDE SEA BREEZE DEVELOPMENT.
&&
.MARINE...
HIGH PRESSURE REMAINS CENTERED NORTH OF THE WATERS WITH NE AND
EAST WINDS IN THE 10 TO 20 KT RANGE DURING THE UP COMING WEEK...
WITH THE HIGHER SPEEDS OFFSHORE. THE LOCATION OF THIS HIGH WILL
RESULT IN NOCTURNAL EASTERLY WIND SURGES DURING THE NEXT FEW NIGHTS
AND MOST LIKELY REQUIRE CAUTION HEADLINES.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 90 71 90 72 / 20 10 10 10
FMY 91 70 92 71 / 20 10 10 10
GIF 91 69 90 70 / 10 10 10 10
SRQ 92 70 92 71 / 20 10 10 10
BKV 90 64 91 66 / 20 10 10 10
SPG 90 75 88 74 / 20 10 10 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE...MROCZKA
AVIATION...JILLSON
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1013 AM CDT SUN JUN 17 2012
.DISCUSSION...
ISSUED 1012 AM CDT SUN JUN 17 2012
A FEW BOUNDARIES CONTINUE TO LOITER ACROSS THE AREA FROM OVERNIGHT
CONVECTION. BEST ESTIMATE OF THE ACTUAL SURFACE FRONT...WHICH IS
MORE OF A DEW POINT DISCONTINUITY...IS FROM QUINCY TO THE NORTHEAST
TIP OF ILLINOIS. HAD SOME LOW CLOUDS FORM IN THE RAINIER AREAS
ACROSS THE ILLINOIS RIVER VALLEY...WITH LATEST OBSERVATIONS AND
SATELLITE IMAGERY SHOWING THEM LINGERING FROM AROUND PEORIA TO
CHAMPAIGN AND DANVILLE. AREAS SOUTHEAST OF I-70 ALSO SEEING QUITE
A BIT OF CLOUDS BELOW 1500 FEET.
MAIN QUESTION FOR TODAY IS POTENTIAL FOR CONVECTIVE REDEVELOPMENT.
LATEST RAP MODEL SHOWING SUBSIDENCE OVERSPREADING THE AREA FROM
THE NORTH THIS AFTERNOON...SUPPRESSING ANY CUMULUS. RAP...HRRR AND
NAM MODELS SUGGEST DEVELOPMENT IN AN AREA WHERE DEWPOINTS POOL IN
THE LOWER 70S...GENERALLY FROM CENTRAL MISSOURI INTO SOUTHERN
ILLINOIS. BULK OF THIS APPEARS TO BE JUST SOUTH OF OUR FORECAST
AREA...BUT CLOSE ENOUGH TO JUSTIFY MENTIONING SOME ISOLATED
SHOWERS/STORMS IN THE SOUTHEAST CWA.
HAVE ALSO MADE SOME MINOR ADJUSTMENTS TO THE TEMPERATURES ACROSS
THE NORTH...WHERE THE CLOUDS HAVE SLOWED THE DIURNAL TEMPERATURE
RISE. UPDATED ZONES/GRIDS HAVE BEEN SENT.
GEELHART
&&
.AVIATION...
ISSUED 645 AM CDT SUN JUN 17 2012
IFR CONDITIONS WILL PERSIST AT BOTH KPIA AND KBMI FOR THE NEXT
COUPLE OF HOURS...BEFORE LOW-LEVEL CLOUDS GRADUALLY DISSIPATE
AFTER 14Z. AFTER THAT...MOSTLY CLEAR SKIES WILL PREVAIL FOR THE
BALANCE OF THE DAY. WITH MOIST AIRMASS REMAINING IN PLACE...CU-RULE
SUGGESTS SCT CU AT AROUND 4000FT FROM LATE MORNING INTO THE
AFTERNOON. MOSTLY CLEAR SKIES WILL CONTINUE INTO TONIGHT AS
WELL...WITH PERHAPS A FEW MID-LEVEL CLOUDS FROM TIME TO TIME AS A
WARM FRONT LIFTS NORTHWARD THROUGH THE AREA. WINDS WILL INITIALLY
BE FROM THE W/SW AT AROUND 10KT TODAY...THEN WILL BACK TO
SOUTHERLY BY THIS EVENING.
BARNES
&&
.PREV DISCUSSION...
ISSUED 330 AM CDT SUN JUN 17 2012
SHORT TERM...TODAY THROUGH WEDNESDAY
MCS WEAKENING OVER EASTERN AND SOUTHERN IL EARLY THIS MORNING
WITH SCATTERED SHOWERS EAST OF HIGHWAY 51. THUNDERSTORMS MAINLY
CONFINED TO SOUTHERN MO INTO SW IL SOUTH OF I-64 AND WEST OF I-57.
MCS WAS AHEAD OF COLD FRONT PRESSING SE INTO SE WI AND FAR NW IL.
MUGGY DEWPOINTS OF 65 TO 70F ACROSS MUCH OF CENTRAL AND SE IL.
00Z MODELS CONTINUE TO TREND FURTHER SOUTH WITH CONVECTION CHANCES
TODAY AND LESS CLOUD COVER OVER CENTRAL IL TODAY...AND MAINLY CONFINED
20-40% CHANCES OF SHOWERS AND THUNDERSTORMS TO SOUTHEAST IL AS COLD
FRONT SWEEPS SE THROUGH CENTRAL IL THIS MORNING AND WEAKENS INTO
SE IL THIS AFTERNOON. SPC DAY1 OUTLOOK DOES NOT HAVE A SLIGHT RISK
OVER SE IL TODAY...WITH 5% AREA SE OF I-70 FOR DAMAGING WIND GUSTS
THIS AFTERNOON AND EARLY EVENING UNTIL SUNSET MAINLY DUE TO SOME
INSTABILITY WITH CAPES PEAKING NEAR 2000 J/KG THIS AFTERNOON.
FRONTAL BOUNDARY LIFTING BACK NORTH TONIGHT HAS LIMITED LIFT ALONG
IT SO JUST ISOLATED SHOWERS AND THUNDERSTORMS POSSIBLE. HIGHS
MOSTLY IN THE UPPER 80S TODAY WITH LAWRENCEVILLE NEAR 90F AND STAYING
HUMID IN SE IL WHILE BECOMING LESS HUMID OVER CENTRAL IL BEHIND
THE FRONT.
STRONG UPPER LEVEL RIDGE BUILDING OVER THE MID MS AND OHIO VALLEYS
MON THROUGH WED TO RETURN HOT AND DRY WEATHER TO CENTRAL AND SE IL
WITH HIGHS IN THE LOW TO MID 90S. STORM TRACK TO REMAIN NORTH OF
IL DURING THIS TIME OVER MN AND CENTRAL AND NW PARTS OF IA/WI.
MODELS CONTINUE TO INCREASE WIND SPEEDS EARLY THIS WORK WEEK
ESPECIALLY MON WITH TIGHTER PRESSURE GRADIENT AND HAVE SSW WIND
GUSTS OF 30 TO 40 MPH MON AFTERNOON.
LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY
LOW PRESSURE EJECTING NE INTO ONTARIO WED NIGHT/THURSDAY TO DRIVE
A COLD FRONT SE INTO IL THU. THIS TO RETURN A CHANCE OF SHOWERS
AND THUNDERSTORMS AND SHIFTING MORE INTO SOUTHERN IL FRIDAY. TEMPS
COOL BACK TO NORMAL LATE THIS WEEK WITH HIGHS IN THE MID TO UPPER
80S FRI/SAT. BUT SOME MODELS LIKE THE 00Z ECMWF SHOW STRONG UPPER
LEVEL RIDGE MOVING BACK INTO THE MID MS VALLEY BY NEXT SUNDAY
WHICH WOULD RETURNING HOTTER TEMPERATURES.
KH
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
714 AM EDT SUN JUN 17 2012
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 203 AM EDT SUN JUN 17 2012
A WEAK FRONT WILL CROSS INDIANA AND THEN MOVE OFF TO THE NORTHEAST
TODAY. FOR MONDAY THROUGH WEDNESDAY EXPECT THE HOOSIER STATE TO BE
WEDGED BETWEEN HIGH PRESSURE ALONG THE EAST COAST AND A COLD FRONT
OVER THE PLAINS. THE FRONT SHOULD FINALLY CROSS INDIANA
THURSDAY...THEN BE FOLLOWED BY HIGH PRESSURE THAT WILL LINGER
THROUGH THE WEEK.
&&
.NEAR TERM /TODAY/...
ISSUED AT 203 AM EDT SUN JUN 17 2012
POPS ARE THE PROBLEM OF THE DAY.
STORMS TO OUR WEST ARE DYING AS THEY SLOWLY MOVE EAST...BUT ARE
APT TO LEAVE BOUNDARY SOMEWHERE OVER US TODAY. NONE OF THE
SYNOPTIC MODELS ARE LIKELY TO HANDLE THIS WELL. HOWEVER...THEY
ALL HAVE A WEAK WAVE CROSSING ALOFT TODAY WHICH WILL LIKELY IGNITE
CONVECTION WHEREVER THE BOUNDARY IS.
TO REALLY GET A GOOD HANDLE ON THE SITUATION...WE MAY HAVE TO WAIT
UNTIL THE RUC FORECASTS START EXTENDING WELL INTO THE DAY PERIOD.
FOR NOW I WILL BASICALLY USE A MET MAV ENSEMBLE TO GET THE BEST
OF EACH. HOWEVER...I WILL AT LEAST BE CHANCE AS OPPOSED TO SLIGHT
CHANCE EVERYWHERE. WILL SAY LIKELY IN NORTHWEST. WHILE
PRECIPITATION NOW THERE MAY DIE BY 12Z...NEED TO ACCOUNT FOR IT
SOMEWHAT WITH THIS PACKAGE.
WITH SO MUCH UNCERTAINTY ABOUT CLOUDS AND PRECIPITATION...WILL
TAKE CONSENSUS OF GUIDANCE TEMPERATURES...AGAIN TO CAPTURE
ENSEMBLE EFFECT.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
ISSUED AT 203 AM EDT SUN JUN 17 2012
PROBLEM IS RAIN CHANCES THROUGH MONDAY. AFTER THAT MODELS CONCUR
RIDGE BUILDING OVER AREA SHUTTING PRECIPITATION DOWN.
WE COULD GET STORMS EARLY TONIGHT FROM STUFF THAT FIRES DURING DAY
AND SURVIVES INTO EVENING. AFTER THAT SOME STUFF COULD STILL DEVELOP
IN WARM HUMID AIR UNTIL RIDGE REALLY BUILDS BY TUESDAY EVENING.
DONT SEE HOW I CAN BEAT THE GUIDANCE THIS FAR IN THE FUTURE. WILL
COMBINE MAV AND MET HOPING FOR BEST OF BOTH.
ON TEMPERATURES USING THE MET. MAV HAS NOT BEEN DOING WELL
IN UNSEASONABLE WARMTH LATELY.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
ISSUED AT 245 AM EDT SUN JUN 17 2012
STRONG UPPER LEVEL RIDGE WILL STILL BE IN CONTROL OVER THE AREA
EARLY IN THE LONG TERM PERIOD...HOWEVER GUIDANCE DEPICTS AN UPPER
LEVEL WAVE AND ASSOCIATED COLD FRONT HELPING TO ERODE THE RIDGE
SOMEWHAT AND SHUTTLE IT TO THE EAST THURSDAY AND FRIDAY. THIS
MERITS AT LEAST SOME LOW THUNDERSTORM CHANCES DURING THIS
TIME...AND INITIALIZATION HANDLED THIS RELATIVELY WELL...WITH SOME
TWEAKS.
SURFACE HIGH SETTLES ACROSS THE AREA IN THE WAKE OF THE
FRONT...AND GUIDANCE DEPICTS BROAD RIDGING ALOFT STRENGTHENING TO
OUR WEST OVER THE WEEKEND. THAT SAID...MODELS HINT AT THE
POTENTIAL FOR THUNDERSTORM ACTIVITY...PERHAPS IN THE FORM OF ONE
OR MORE MCS/S...DURING PORTIONS OF THE WEEKEND IN THE NORTHWEST
FLOW. THIS...AND THE SLIGHT CHANCE POPS INTIALIZATION GAVE TO
HANDLE IT...APPEAR REASONABLE...ESPECIALLY AS WE ARE ENTERING THE
TIME OF YEAR WHEN ORGANIZED RIDGE RIDING CONVECTION IN NORTHWEST FLOW
BECOMES RELATIVELY COMMON. DUE TO SIGNIFICANT UNCERTAINTY...CANNOT
JUSTIFY MORE THAN SLIGHT CHANCE POPS FOR PORTIONS OF THE REGION
AT THE MOMENT.
REMAINDER OF BLEND WAS REASONABLE...WITH A FEW MINOR TWEAKS TO
MAX/MIN TEMPS AFTER CONSULTING 850 TEMP PROGS. ASIDE FROM WHAT
LOOKS TO BE BRIEF RETURN TO NEAR NORMAL TEMPS FRIDAY AND
SATURDAY...90 DEGREE HEAT WILL NOT BE GOING ANYWHERE ANYTIME SOON
FOR LENGTHY PERIODS.
&&
.AVIATION /DISCUSSION FOR THE 17/12Z TAF ISSUANCE/...
ISSUED AT 714 AM EDT SUN JUN 17 2012
VFR THROUGH THE PERIOD.
VERY WIDELY SCATTERED SHOWERS PUSHING THROUGH THE AREA THIS
MORNING...BUT ARE UNLIKELY TO SIGNIFICANTLY IMPACT TAF
SITES...BEYOND PERHAPS A SPRINKLE OR TWO EARLY. NO THUNDER
ASSOCIATED WITH THEM.
REDEVELOPMENT OF CONVECTION IS POSSIBLE THIS AFTERNOON ALONG ANY
REMNANT BOUNDARIES...BUT IT APPEARS LIKELY...AND THIS IS SUPPORTED
BY SREF PROBABILTIES...THAT THUNDER WOULD BE MOST LIKELY IN THE
EASTERN OR SOUTHEASTERN PORTIONS OF INDIANA...AND PERHAPS NOT
IMPACTING THE TAF SITES. UNCERTAINTY PRECLUDES ANY SORT OF MENTION
FOR THE MOMENT...AND WILL HAVE TO MONITOR AND AMEND IF IT BECOMES
NECESSARY...AS MESOSCALE DETAILS OF THE AFTERNOON SHAKE OUT.
WINDS WILL BE SOUTHWESTERLY TO WESTERLY...AROUND 10KT DURING THE
DAY...LESSER EARLY TODAY AND OVERNIGHT.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...JK
NEAR TERM...JK
SHORT TERM...JK
LONG TERM....NIELD
AVIATION...NIELD
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
741 AM EDT SUN JUN 17 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 521 AM EDT SUN JUN 17 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A SHORTWAVE TROF FROM NRN
MANITOBA TO THE UPPER GREAT LAKES BEGINNING TO BE FORCED NE DUE TO
RIDGE EXTENDING FROM THE OHIO VALLEY TO QUEBEC. STRONG SURGE OF
DRIER AIR IS FOLLOWING SHORTWAVE PER 00Z SOUNDINGS WHICH SHOWED
PRECIPITABLE WATER DOWN BLO ONE-HALF INCH OVER THE DAKOTAS.
IMPRESSIVELY DRY AIR WAS NOTED BTWN ROUGHLY 700-500MB ON 00Z
KINL/KBIS SOUNDINGS. DWPT DEPRESSIONS WERE WELL IN EXCESS OF 30C.
KBIS SOUNDING ALSO SHOWED A DRY WELL-MIXED BOUNDARY LAYER. THIS IS
THE AIR MASS THAT WILL BE QUICKLY SHIFTING ACROSS THE AREA TODAY...
RESULTING IN A WARM DAY WITH COMFORTABLE HUMIDITY LEVELS. MIXING TO
800-750MB ON FCST SOUNDINGS YIELDS MAX TEMPS IN THE MID 70S TO LWR
80S. WEAKENING WRLY BOUNDARY LAYER FLOW THIS AFTN WILL ALLOW LAKE
BREEZE DEVELOPMENT TO PROVIDE SOME AFTN COOLING NEAR THE GREAT
LAKES. DRY AIR AVBL TO MIX DOWN SHOULD RESULT IN SFC DWPTS FALLING
TO THE UPPER 40S/LWR 50S IN GENERAL AWAY FROM LAKE MODIFICATION.
SOME LOW/MID 40S NOT OUT OF THE QUESTION GIVEN MAGNITUDE OF DRY AIR
ALOFT. SUN WILL MIX WITH HIGHER BASED CU DURING THE DAY.
AS FAST AS THE DRYING OCCURRED TODAY...MOISTURE WILL QUICKLY RETURN
TONIGHT ON STRENGTHENING SW FLOW IN RESPONSE TO SHORTWAVE ENERGY
RACING ACROSS THE NRN PLAINS. 850MB THETA-E ADVECTION/MOISTURE
ADVECTION IS IMPRESSIVE TONIGHT AS LOW-LEVEL JET RAMPS UP TO 40-50KT
AND TAKES AIM AT UPPER MI. WHILE BEST MUCAPE TO THE SW SHOULD RESULT IN
STRONGER CONVECTION OCCURRING TO THE SW/S AND THUS INTERCEPTING SOME
OF THE MOISTURE TRANSPORT TO UPPER MI...OVERALL DEGREE OF DEEP LAYER
FORCING TO THE N AND BUILDING 850-300MB THICKNESS RIDGE FARTHER N
WITH TIME SUGGEST CONVECTIVE DEVELOPMENT SHOULD EXTEND N AND NE WITH
TIME AS WELL. WITH EXPECTATION OF STRONGER CONVECTION TO THE S/SW
INTERCEPTING INSTABILITY TRANSPORT...NOT ANTICIPATING ANY SVR STORMS
TONIGHT. HOWEVER...SHOULD STRONGER STORMS TO THE S/SW WEAKEN...
ADVECTION OF INSTABILITY TO THE NE COMBINED WITH MARGINAL EFFECTIVE
DEEP LAYER SHEAR COULD LEAD TO SOME HAIL PRODUCING STORMS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 521 AM EDT SUN JUN 17 2012
EXPECT A GOOD CHANCE OF SHOWER AND THUNDERSTORM ACTIVITY MOST
PERIODS THROUGH WEDNESDAY NIGHT...ALONG WITH PATCHY FOG OVER
PORTIONS OF LAKE SUPERIOR. WE BEGIN THE PERIOD WITH W/SW FLOW AT
500MB...WITH HIGH PRESSURE BUILDING ACROSS THE MID ATLANTIC STATES
AND A SERIES OF WAVES SLIDE ACROSS OR NORTH OF UPPER MI.
WILL LOOK FOR A POTENTIAL MCS TO PUSH ACROSS THE AREA MONDAY
AFTERNOON INTO THE EVENING HOURS...AS THE NEARING SFC LOW SHIFTS FROM
THE EASTERN DAKOTAS AT 06Z MONDAY AND CROSSES MN MONDAY AFTERNOON
BEFORE EJECTING ACROSS LAKE SUPERIOR AND ONTARIO. CONTINUE TO
HIGHLIGHT STRONG WINDS AND HAIL THREAT IN THE HWO. EXPECT STRONG
WINDS JUST OFF THE SFC FROM 4-13Z MONDAY W...08-17Z MONDAY S CENTRAL
/SLIGHTLY LESS PRONOUNCED AND SLOWER OFF THE GFS/...AND MORE LIKE 12Z
MON-00Z TUE E...IN THE 50-60KT RANGE. LLWS WILL BE LIKELY A THREAT
FOR FOR AVIATION USERS...WITH STRONG WINDS JUST ABOVE THE SFC AND
ALOFT. EXPECT DCAPE VALUES NEAR 1K J/KG NEAR THE WI BORDER BY
18Z...WITH STRONG WINDS BEING A POSSIBILITY WITH ANY TSRA THAT
DEVELOPS. 0-2KM LAPSE RATES LOOK TO TOP OUT AROUND 6-7C/KM...WITH A
THIN LINE UP TO AROUND 8C/KM OVER THE INTERIOR W HALF OF UPPER MI BY
00Z TUESDAY...LINING UP WITH 1K-2K J/KG CAPE VALUES. EVEN THE 0-3KM
CAPE IS 0.5-1K J/KG OVER THE W HALF BY 18Z...WITH A CONTINUATION
CENTRAL AND E THROUGH 00Z TUE. CIN LOOKS TO BE AOB 40 J/KG OVER THE
INTERIOR W HALF...WITH AN INDICATION OF ELEVATED STORMS CENTRAL AND E
OF A LINE FROM ALGER TO DELTA COUNTY AT LEAST INITIALLY. EXPECT TO
SEE STRONGER STORMS NEARING FROM THE WSW...TO DIMINISH AS THEY PUSH
INTO THE LESS FAVORABLE AREAS OF CENTRAL AND E UPPER MI.
WHILE THE COLD FRONT BRIEFLY SINKS JUST SE OF THE CWA MONDAY
NIGHT...IT WILL RETURN IN THE FORM OF A WARM FRONT TUESDAY
AFTERNOON...IN RESPONSE TO THE NEXT SFC LOW EDGING ACROSS MN FROM
THE CENTRAL PLAINS. CAPE VALUES AGAIN NEAR 1K J/KG TUESDAY AS THIS
LOW TOO PUSHES ACROSS W LAKE SUPERIOR AND INTO ONTARIO TUESDAY NIGHT
INTO EARLY WEDNESDAY. ATTEMPTED TO DRY OUT AREAS NEAR LAKE MI
TUESDAY NIGHT...OUT AHEAD OF THE APPROACHING COLD FRONT. TIMING OF
THE COLD FRONT IS A BIT TRICKY...BUT SHOULD BE OVER THE W THIRD OF
THE CWA BY AT LEAST 18Z WEDNESDAY. COMPARING MODEL OUTPUT...THE
17/06Z NAM IS ON THE QUICK END OF MODEL SOLUTIONS AT LEAST SFC
WISE...WITH THE 17/00Z RUN OF THE CANADIAN AT LEAST 12 HOURS BEHIND
THE NAM. THE GFS AND ECMWF LOOK TO BE BETTER SOLUTIONS FOR THE
PROGRESSION OF THIS SYSTEM.
ALTHOUGH SLIGHT CHANCE POPS LINGER INTO THE DAY THURSDAY...MOST OF
THE SHOWER ACTIVITY SHOULD BE E OF OUR AREA...ALTHOUGH THE 500MB
TROUGH WILL STILL BE OVERHEAD. EXPECT 8-10C 850MB TEMPS THURSDAY
INTO EARLY FRIDAY ON NW-W FLOW BEHIND THE EXITING COLD FRONT...WHICH
SHOULD KEEP SFC TEMPS AT OR SLIGHTLY BELOW NORMAL FOR THIS TIME OF
YEAR. THERE LOOKS TO BE SOME MINOR INDICATIONS IN A PATTERN CHANGE
ALOFT. THE 500MB RIDGE OVER THE MID ATLANTIC/OHIO VALLEY SHOULD
BECOME SUPPRESSED THURSDAY NIGHT...IN RESPONSE TO THE YET ANOTHER
500MB LOW PASSING OVER ONTARIO. THIS LAST ONE LOOKS TO GET HELD UP
OVER S HUDSON BAY/QUEBEC AS THE 500MB RIDGE PUSHES UP ACROSS THE
CENTRAL PLAINS STATES FOR FRIDAY THROUGH SUNDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 739 AM EDT SUN JUN 17 2012
PER UPSTREAM 00Z SOUNDINGS...DRY AIR SWINGING THRU THE AREA IN THE
WAKE OF SHORTWAVE MOVING NE THRU NRN ONTARIO WILL ENSURE VFR
CONDITIONS THRU THE AFTN AT KIWD/KCMX/KSAW. DEEP MIXING WILL RESULT
IN GUSTY WESTERLY WINDS...ESPECIALLY AT THE MORE EXPOSED KCMX SITE.
STRENGTHENING LOW-LEVEL JET/STRONG MOISTURE RETURN TONIGHT IN
RESPONSE TO SHORTWAVE ENERGY MOVING ACROSS THE NRN PLAINS WILL BRING
INCREASING RISK OF CONVECTION AS THE NIGHT WEARS ON. INCLUDED SHRA AT
ALL 3 TERMINALS OVERNIGHT AS LOW-LEVEL JET TAKES AIM AT THE AREA. MAY
SEE SOME THUNDER...BUT CONFIDENCE IN THUNDER OCCURRING AT ANY OF THE
TERMINALS IS LOW ENOUGH AT THIS POINT TO NOT INCLUDE MENTION. WITH
LOW-LEVEL JET ARRIVING...INCLUDED LLWS EXCEPT AT KIWD AS WINDS SHOULD
RETAIN SOME GUSTINESS THERE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 521 AM EDT SUN JUN 17 2012
A BRIEF RIDGE OF HIGH PRESSURE TODAY...BEHIND THE EXITING SFC
LOW/TROUGH WILL MAKE WAY FOR THE NEXT LOW DEVELOPING OVER S CANADA
AND THE NORTHERN PLAINS STATES. EXPECT THE NORTHERN LOW TO PUSH
ACROSS ONTARIO MONDAY /WITH GUSTS NEARING 30-35KTS CENTRAL AND
E/...WITH A TROUGH EXTENDING THROUGH LS AND INTO NE. GIVEN THE
ADDITIONAL MOISTURE ACROSS THE AREA WITH THE TROUGH NEARBY FOR MUCH
OF THE PERIOD...FOG WILL BE A COMMON THEME. A SECONDARY LOW
OVER NE WILL RIDE UP THE TROUGH AND CROSS LS AND PUSH INTO ONTARIO
WEDNESDAY AFTERNOON/EVENING...WHICH WILL FINALLY PUSH THE TROUGH SE
OF THE AREA. HIGH PRESSURE WILL THEN SLOWLY BUILD IN AND LINGER
THURSDAY THROUGH THE START OF THE UPCOMING WEEKEND. WSW GUSTS MAY
INCREASE AGAIN TO NEAR 25-30KTS THURSDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KF
AVIATION...ROLFSON
MARINE...KF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1056 AM CDT SUN JUN 17 2012
.UPDATE...
.MESOSCALE DISCUSSION...
THUNDERSTORMS ARE RAPIDLY MOVING INTO SW MN THIS MORNING ON NOSE
OF RAP ANALYZED 40+ KT LLJ AND WITHIN ZONE OF STRONG H85 WAA.
LATEST SPC MESOANALYSIS SHOWS 2000+ J/KG OF MUCAPE FEEDING UP INTO
THIS AREA OF WAA...WITH THE EXPANSION OF THUNDERSTORMS OVER
SOUTHWEST MINNESOTA RESULTING. 0-6KM DEEP LAYER SHEAR IS AROUND 40
KTS RIGHT NOW...SO A MARGINAL RISK FOR HAIL WILL EXIST WITH THIS
PRIMARILY ELEVATED CONVECTION FROM THE MORNING INTO THE EARLY
AFTERNOON. THESE STORMS WILL BE WORKING OVER TO THE I-35 CORRIDOR
SHORTLY AFTER 18Z...WITH THE THREAT FOR HAIL CONTINUING. IF THESE
STORMS CAN BECOME ROOTED IN THE BOUNDARY LAYER LATER THIS
AFTERNOON...THEN A RISK FOR DAMAGING STRAIGHT LINE WINDS WILL
EXIST AS WELL.
FOR THE SEVERE RISK LATER THIS AFTERNOON /WHICH IS WHAT PROMPTED
THE MODERATE RISK FROM THE SPC/...THE BIG QUESTION REMAINS HOW FAR
NORTH DOES A VERY WARM EML AND ATTENDANT STRONG CAPPING INVERSION
MAKE IT. TREND FROM THE LAST FEW RUNS OF THE RAP/HRRR SHOW THAT
THE SEVERE THREAT FOR LATER THIS AFTERNOON LIKELY HAS SHIFT NORTH
SOME FROM WHAT GUIDANCE LAST NIGHT WAS SHOWING. THIS NORTHWARD
SHIFT IS ALSO SUPPORTED BY THE LATEST 12Z NAM. BASED ON A RAP/NAM
COMBO...WARM FRONT LOOKS TO COME INTO WRN MN SOMEWHERE BETWEEN
WHEATON AND MARSHALL...WITH CONVECTION INITIATING BETWEEN 3 AND 5
PM IN NE SODAK/WEST CENTRAL MINNESOTA. BELIEVE THE HRRR
REFLECTIVITY FORECAST IS A BIT NORTH WITH THINGS BASED ON WHERE
THE RAP PLACES SFC FEATURES...BUT SUSPECT THE STRONG CAP MAKES IT
DIFFICULT TO SEE MUCH OF ANYTHING THIS AFTERNOON/EVENING SOUTH OF
YELLOW MEDICINE COUNTY. GIVEN 2000-3000 J/KG OF MIXED LAYER
CAPE..ALONG WITH 0-6 KM SHEAR INCREASING TO AROUND 60 KTS...AND
0-1KM SHEAR PEGGED BY THE RAP TO BE BETWEEN 30 AND 40
KTS...WHATEVER DOES GET GOING IN WEST CENTRAL MN WILL HAVE A HIGH
LIKELIHOOD OF BEING SUPERCELLULAR WITH THE ATTENDANT RISK FOR VERY
LARGE HAIL...STRONG WINDS...AND TORNADOES EXISTING. STILL LOOKING
LIKE THIS ACTIVITY WILL CONGEAL INTO A LINEAR SYSTEM THIS EVENING
AND TRACK EAST ACROSS THE REST OF MINNESOTA INTO WI TONIGHT. WITH
THE NRN SHIFT IN MODELS...SUSPECT GREATEST THREAT OF SEVERE
WEATHER THROUGH TONIGHT WILL BE ALONG AND NORTH OF THE I-94 WITH
WHAT IS EXPECTED TO BE AN MCS. SOUTHERN MN MAY END UP NOT SEEING
MUCH AFTER THIS MORNING DUE TO INCREASING CAP STRENGTH.
&&
.PREV DISCUSSION...
/ISSUED 605 AM CDT SUN JUN 17 2012/
ACTIVE WEATHER REMAINS ON TRACK TO CONTINUE ACROSS THE REGION FOR
THE NEXT SEVERAL DAYS. STRONG TO SEVERE THUNDERSTORMS WILL DEVELOP
TOMORROW AFTERNOON OUT WEST AND MOVE EASTWARD ACROSS THE CWA
OVERNIGHT. A FRONTAL BOUNDARY WILL STALL ACROSS THE REGION...AND
THIS WILL BE THE FOCUS FOR REPEATED ROUNDS OF SHOWERS AND
THUNDERSTORMS. FLOODING ALSO REMAINS A CONCERN WITH TRAINING
THUNDERSTORMS POSSIBLE DURING THIS TIME PERIOD. THINGS WILL TRY TO
QUIET DOWN TOWARD THE END OF NEXT WEEK.
TODAY THROUGH WEDNESDAY....EARLY MORNING WATER VAPOR IMAGERY OVERLAID
WITH 500MB HEIGHTS AND H250 WINDS SHOWS A TREMENDOUS +150KT PACIFIC
JET CRASHING ONSHORE OVER THE PUGET SOUND AND RACING TOWARD THE
IDAHO PANHANDLE. THIS WILL BE THE MAIN PLAYER IN THE NEAR-TERM
WEATHER ACROSS THE UPPER MIDWEST. CLOSER TO HOME AT THE
SURFACE...A COLD FRONT HAD PUSHED THROUGH THE CWA WITH A RIDGE
OF HIGH PRESSURE CENTERED OVER THE MISSOURI RIVER VALLEY. A
LEE SIDE SURFACE LOW WAS BEGINNING TO DEVELOP ACROSS THE HIGH
PLAINS OF MONTANA IN RESPONSE TO THE APPROACHING JET...AND THIS
WILL CONTINUE TO DEEPEN OVER THE NEXT 18 HOURS AND INDUCE
SOUTHERLY FLOW ACROSS THE CENTRAL PLAINS. THE COLD FRONT WHICH
JUST MOVED THROUGH WILL SURGE NORTHWARD AS A WARM FRONT AND BE
DRAPED ACROSS EASTERN SOUTH DAKOTA THROUGH SOUTHWEST MINNESOTA. A
CONDITIONAL SEVERE THREAT EXISTS IN THE VICINITY OF THIS BOUNDARY.
THE ATMOSPHERE WILL BECOME VERY UNSTABLE...WITH SBCAPES OF 2000 TO
3000J/KG IN THE WARM SECTOR BY MID AFTERNOON. FORECAST SOUNDINGS
SHOW STRONG VEERING WINDS IN THE LOWER LEVELS...WITH 0-3 HELICITY
VALUES OF INCREASING FROM ABOUT 150 M2/S2 TO OVER 500 M2/S2 ALONG
THE WARM FRONG AS THE BOUNDARY LAYER DECOUPLES. CONVECTION SHOULD
DEVELOP LATE THIS AFTERNOON ACROSS THE EASTERN DAKOTAS...WITH A
FEW TORNADOES POSSIBLE SHORTLY AFTER INITIATION...ESPECIALLY WITH
RIGHT MOVING STORMS THAT ARE ABLE TO GENERATE THEIR OWN SRH.
EXPECT THESE STORMS TO GROW UPSCALE...AND COULD SEE A TRANSITION
TO A DERECHO THAT PROPAGATES ESE ALONG THE AFOREMENTIONED WARM
FRONT. IF THIS SCENARIO PLAYS OUT...EXPECT AN OUTFLOW BOUNDARY TO
REINFORCE THE FRONT ON MONDAY...WHICH WILL MOVE NORTHWARD AGAIN
MONDAY NIGHT AS ANOTHER SURFACE LOW DEVELOPS TO THE SOUTHWEST.
WITH STEERING LAYER WINDS PARALLEL TO THE BOUNDARY...COULD SEE
TRAINING THUNDERSTORMS AND A FLASH FLOOD THREAT FOR MONDAY NIGHT
INTO TUESDAY...IN ADDITION TO ANOTHER ROUND OF SEVERE WEATHER AS A
SHORTWAVE TRAVERSES THE REGION. AS FAR AS TEMPS GO...SOUTH OF THE
BOUNDARY H850 TEMPS WILL EXCEED 20C...SO WILL END UP BEING A HOT
AND HUMID DAY NEAR THE IA/MN BORDER WITH A 20F NORTH TO SOUTH
TEMPERATURE GRADIENT ACROSS THE STATE. SO IN SUMMATION...SPC HAS
UPGRADED WESTERN PORTIONS OF THE CWA TO A MODERATE RISK FOR THE
REASONS LISTED ABOVE....AND A SECOND SEVERE/HEAVY THREAT WILL BE
LATE MONDAY EVENING INTO TUESDAY ACROSS MAINLY THE EASTERN HALF OF
THE CWA AS THE WARM FRONT LIFTS NORTHWARD. FINALLY...THE SOUTHERN
PART OF THE CWA WILL BE LOCATED IN THE WARM SECTOR ON
TUESDAY...AND WILL LIKELY SEE A THIRD ROUND OF STORMS TUESDAY
NIGHT INTO WEDNESDAY MORNING ALONG THE TRAILING COLD FRONT AS THE
PARENT WAVE MOVES ACROSS THE REGION TOWARDS HUDSON BAY.
THURSDAY THROUGH SATURDAY...ONCE THIS ACTIVE PERIOD IS IN THE REAR
VIEW MIRROR...WILL TRANSITION TO NORTHWEST FLOW FOR THE END OF THE
WEEK. BOTH THE ECMWF AND GFS HAVE BEEN CONSISTENT WITH MODERATE
HEIGHT RISES AND WEAK HIGH PRESSURE BUILDING ACROSS THE REGION.
THEREFORE WENT OPTIMISTICALLY DRY FOR THURSDAY AND FRIDAY. ON FRIDAY
NIGHT MODELS TRY TO BRING A SHORTWAVE ACROSS THE HIGH PLAINS...WITH
THETA_E ADVECTION SPREADING ACROSS THE UPPER MIDWEST AHEAD OF IT.
THEREFORE HAVE CONTINUED PRECIP CHANCES FOR THE EARLY PART OF THE
UPCOMING WEEKEND. TEMPERATURES WILL COOL OFF CLOSER TO THE SEASONAL
AVERAGE FOR MID TO LATE JUNE.
&&
.AVIATION... /12Z TAF ISSUANCE/
MUCH DRIER AIRMASS CURRENTLY ACROSS REGION IN THE WAKE OF THE FRONT
WHICH MOVED EAST AND SOUTH THE AREA YESTERDAY EVENING. HOWEVER WINDS
ARE ALREADY BECOMING SOUTHERLY ACROSS NEB INTO W MN AS SURFACE
PRESSURE BEGIN TO DROP ACROSS THE DKTS AHEAD OF THE NEXT TROUGH.
CANOPY OF HIGH AND MID CLDS ACROSS THE DKTS THEN UPSTREAM ACRS THE N
ROCKIES WILL THICKEN ACROSS OUR AREA TODAY. MODELS CONTINUE TO
ADVERTISE A CHANCE OF -SHRA ACRS CNTL MN THIS AFTN...SO HELD ONTO
THE VCSH IN TAFS. MAIN WEATHER EVENT WILL BE STRONG THUNDERSTORMS
DEVELOPING THIS AFTN IN THE DKTS AND THEN SPREADING INTO AXN/RWF BY
22Z. STRONG MID LEVEL WINDS WILL PUSH THESE STORMS RAPIDLY ESE INTO
REMAINING TAFS IN THE EVENING AND OVERNITE. A THREAT THAT THESE
STORMS COULD DEVELOP INTO ONE OR MORE BOWS...MAINLY ACRS S MN THIS
EVENING. CONDITIONS LOWERING TO MVFR/BRF IFR IN TSTMS.
SFC WINDS ACRS AREA WILL BECOME SLY ACRS AREA DURING THE MRNG AND
EARLY AFTN WITH SOME GUSTS 20 TO 25 KTS AXN/RWF.
KMSP...THICKENING HIGH AND MID CLDS DRNG THE DAY WITH CIGS AOA 8K. A
FEW -SHRA PSBL AFT 19Z AS MID CLDS THICKEN IN DEVELOPING WAA. LINE
OF TSTMS PSBL ARND 02Z-06Z WITH POTENTIAL OF SOME STRONG WINDS AS
WELL AS HAIL. MVFR TO BRF IFR IN TSTMS. ALSO THREAT OF MVFR CIGS
DEVLOPING LT TNGHT IN SATURATED AIRMASS FROM EXPECTED PCPN.
SW WINDS BECOME SLY ARND NOON WITH SOME GUSTS ARND 20 KTS DRNG AFTN.
OUTLOOK...
MONDAY...VFR/MVFR WITH CHC OF TSRA. WINDS SW 10KT SHIFTING NW.
TUESDAY...VFR/MVFR WITH TSRA POSSIBLE. SE TO S WINDS 20 TO 25 KTS.
WEDNESDAY...VFR/MVFR WITH TSRA POSSIBLE. WINDS NW AT 12 TO 17 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
MPG/JRB/BAP
AREA FORECAST DISCUSSION
NWS BILLINGS MT
658 AM MDT SUN JUN 17 2012
.SHORT TERM...VALID FOR TDY AND MON...
WE MADE A MINOR UPDATE TO THE FORECAST TO SPREAD SLIGHT CHANCES OF
SHOWERS FURTHER SOUTHEAST INTO THE MILES CITY AND BAKER AREAS THIS
MORNING. THIS IS BASED ON RADAR TRENDS AND THE LAST FEW HRRR RUNS.
THE UPSTREAM SHOWER ACTIVITY MAY INDICATE SUFFICIENT MOISTURE WILL
BE AVAILABLE FOR MIX DOWN THIS AFTERNOON...WHICH COULD KEEP UP THE
HUMIDITY LEVELS A BIT MORE THAN FORECAST. SCHULTZ
PREVIOUS DISCUSSION...ISSUED AT 347 AM MDT SUN JUN 17 2012...
FIRE WEATHER CONCERNS WILL BE ELEVATED TODAY WITH WARM...DRY...AND
WINDY WEATHER ON TAP. HOWEVER...NO HEADLINES WERE ISSUED WITH THIS
FORECAST BECAUSE 1/ IT APPEARS WINDS WILL NOT REACH FULL POTENTIAL
AND 2/ FIRE DANGER CLASS RATINGS AND SOME OTHER TOOLS SUGGEST THIS
WEATHER EVENT MAY NOT BE QUITE ENOUGH TO TIP THE SCALES TOWARD RED
FLAG CONDITIONS...AT LEAST ON A WIDESPREAD BASIS. NONETHELESS...WE
WILL CONTINUE EMPHASIZING THE EXPECTED NEAR CRITICAL CONDITIONS IN
OUR FORECAST PRODUCTS. NOTE THAT A HEADLINE MAY STILL END UP BEING
ISSUED IF WINDS ARE JUST A BIT STRONGER...OR CLOUD COVER IS JUST A
BIT LESS AND PROVIDES LESS SHADING TO FUELS.
TODAY...LOW- AND MID-LEVEL WESTERLY FLOW WILL INCREASE...WITH SOME
40 KT OF WIND AT 700 HPA. MIXING SHOULD EXTEND TO AT LEAST 650 HPA
BASED ON 00 UTC GFS FORECAST SOUNDINGS...WHICH ARE FAVORED BECAUSE
THEY MIX MORE DEEPLY THAN THE NAM PROFILES IN AN ENVIRONMENT WHICH
SHOULD EASILY SUPPORT TURBULENT BOUNDARY LAYER MIXING. HOWEVER...A
LAYER WITH SOME VERTICAL MOTION IS ALSO ADVERTISED BY MODELS AT OR
ABOVE 700 HPA...WHICH WILL LIKELY BE ENOUGH TO KEEP WINDS CAPPED A
BIT BELOW THEIR FULL POTENTIAL. THUS...MOMENTUM TRANSFER FROM MOST
BUFKIT PROFILES IS PROBABLY TOO HIGH IN SHOWING GUST POTENTIAL OF
45 KT. WE ARE STILL FORECASTING WIND SPEEDS A COUPLE NOTCHES ABOVE
MOS-BASED GUIDANCE GIVEN THE DEEP VERTICAL MIXING...BUT WE BELIEVE
MOST GUSTS WILL TOP OUT BETWEEN 30 AND 40 MPH. HIGHS TODAY WILL BE
WELL INTO THE MID AND UPPER 80S F...AND HUMIDITY IS EXPECTED TO BE
NEAR 15 PERCENT IN MOST LOWER ELEVATIONS. THE HUMIDITY FORECAST IS
BASED ON A SIMPLE ONE-DAY ERROR CORRECTION TO THE 00 UTC NAM-BASED
MOS...TAKING INTO ACCOUNT THE SLIGHT MOIST BIAS THAT SAME GUIDANCE
HAD ON SAT. POOR RECOVERY HAS OCCURRED TONIGHT AND THAT IS ANOTHER
SIGN FOR A QUICK HUMIDITY TUMBLE TODAY. HOWEVER...IT IS POSSIBLE A
BIT OF MOISTURE COULD MIX DOWN FROM ALOFT AND KEEP VALUES SLIGHTLY
HIGHER THAN EXPECTED. WE KEPT POPS OUT OF THE FORECAST FOR MOST OF
THE AREA TODAY GIVEN LOW MLCAPE VALUES AND DOWNSLOPE FLOW...THOUGH
THE MID-LEVEL VERTICAL MOTION SHOULD AT LEAST GENERATE HIGH-BASED
CUMULUS OR EVEN VIRGA TO GO WITH HIGH CLOUDS BY LATE AFTERNOON.
TONIGHT...LOW POPS ARE IN PLAY ACROSS THE WHOLE AREA BEFORE 06 UTC
AS A 110-120 KT 300-HPA JET STREAK SETS UP. A BIT HIGHER POPS NEAR
30 PERCENT ARE IN THE FORECAST OVER SOUTHEASTERN MT...WHERE MODEST
MID-LEVEL FRONTOGENESIS IS FORECAST. SEVERAL 00 UTC MODELS SHOW AN
AREA OF LIGHT QPF IN THAT AREA IN RESPONSE TO THIS FORCING...WHICH
INCREASES OUR CONFIDENCE IN GETTING AT LEAST A FEW SHOWERS THERE.
MON INTO MON NIGHT...A 500-HPA SHORT WAVE TROUGH WILL MOVE IN FROM
THE WEST AND HAVE ITS AXIS OVER CENTRAL MT BY 12 UTC TUE. WE DON/T
HAVE MUCH CONFIDENCE IN THE DETAILS OF THIS EVOLUTION GIVEN RECENT
MODEL TRENDS...AND A BACKGROUND PATTERN THAT HAS NOT BEEN TOO GOOD
AT YIELDING MUCH DEPTH TO INDIVIDUAL WAVES. THE 00 UTC ECMWF COULD
BE A GOOD COMPROMISE TO THE FULL SET OF MODEL IDEAS THOUGH...WHICH
SUPPORTS CHANCE POPS ACROSS THE WHOLE AREA ON MON NIGHT. NOTE THAT
DURING THE DAY ON MON OUT AHEAD OF THE WAVE...THERMAL PROFILES ARE
STILL WARM ENOUGH FOR WIDESPREAD 70S F. SCHULTZ
.LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT...
BROAD CYCLONIC FLOW WILL PREVAIL OVER OUR REGION TUESDAY INTO
WEDNESDAY. LONG RANGE MODELS ARE IN GENERAL AGREEMENT THAT A
POWERFUL RIDGE WILL BUILD OVER THE CENTRAL UNITED STATES FOR THE
LATTER PART OF THE WORK WEEK AND AFFECT THE HIGH PLAINS AND
ROCKIES AS WELL. THUS...EXPECT A COOL AND WET PATTERN TUESDAY TO
TRANSITION TO ONE WITH ABOVE NORMAL TEMPERATURES AND MAINLY DRY
CONDITIONS BY THURSDAY AND FRIDAY. THAT SAID...THE GFS DOES
INDICATE A STRONG LOW LEVEL SOUTHEASTERLY JET FRIDAY INTO SATURDAY
INCREASING DEWPOINTS IN THE BOUNDARY LAYER LEADING TO EXTREMELY
HIGH HIGH CAPE VALUES FROM 2500 TO 3000 J/KG. HOWEVER...BUFKIT
SOUNDINGS SHOW AN INITIALLY CAPPED ENVIRONMENT...BUT A POTENTIAL
FOR ELEVATED CONVECTION ALONG A STATIONARY FRONT FRIDAY
NIGHT...AND THEN THE CAP BREAKING ON SATURDAY AFTERNOON. WILL NEED
TO KEEP AN EYE ON THIS POSSIBLE SCENARIO AS PROGGED SHEAR AND CAPE
VALUES ARE DANGEROUSLY HIGH AT THIS POINT FOR NEXT WEEKEND.
FOR THIS PACKAGE...DID NOT MAKE ANY SIGNIFICANT CHANGES TO THE
EXTENDED PERIODS. BT
&&
.AVIATION...
VFR CONDITIONS ARE EXPECTED TODAY WITH JUST ISOLATED THUNDERSTORMS
OVER THE FORECAST AREA THIS AFTERNOON AND EVENING. THE MAIN
AVIATION HAZARD SUNDAY WILL BE WESTERLY SURFACE WINDS 20 TO 30 KTS
BECOMING COMMON IN THE AFTERNOON. GUSTS TO 45 KTS ARE POSSIBLE IN
THE KLVM VICINITY. BT
&&
.PRELIMINARY POINT TEMP/POPS...
TDY MON TUE WED THU FRI SAT
-------------------------------------------------------
BIL 087 055/076 051/068 049/073 050/081 055/091 059/087
1/N 22/T 54/T 33/W 10/B 00/U 22/T
LVM 083 045/075 042/063 040/069 042/079 048/085 052/083
2/T 22/T 54/T 32/W 10/B 00/U 01/U
HDN 088 055/080 051/071 050/075 050/084 054/095 058/090
1/N 22/T 44/T 33/W 10/B 00/U 22/T
MLS 089 058/080 054/072 053/075 053/082 058/090 061/086
2/W 21/U 44/T 53/T 21/B 10/U 22/T
4BQ 088 056/082 053/073 052/073 051/081 056/092 061/087
1/N 31/N 32/T 43/T 10/B 01/U 22/T
BHK 086 056/077 053/071 051/072 051/079 055/086 059/083
2/W 31/N 44/T 53/T 21/B 10/U 22/T
SHR 086 052/082 048/067 048/069 047/078 053/090 058/087
0/B 21/B 32/T 22/W 10/U 00/U 12/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1001 AM EDT SUN JUN 17 2012
.SYNOPSIS...
WARM FRONT CROSSES THIS MORNING. AN UPPER LEVEL DISTURBANCE CROSSES
THIS AFTERNOON AND TONIGHT...AND ANOTHER CROSSES MONDAY. UPPER
RIDGE TAKES HOLD FOR MID WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
1000 AM UPDATE...HAVE A COUPLE LINES OF CONVECTION ON THE RADAR. THE
FIRST ONE...A BROKEN LINE FROM NEAR ZZV TO HTS IS ALONG A DEWPOINT
GRADIENT/WARM FRONT. SOME LOCAL DOWNPOURS AND EMBEDDED THUNDER. ALSO
SOME ISOLATED CONVECTION DEVELOPING AHEAD OF THIS LINE...CLOSER TO
THE MOUNTAINS...BUT AS OF NOW NOT MUCH MORE THAN SOME LIGHT SHOWERS.
THE SECOND...STRONGER LINE IS FARTHER WEST...RUNNING A LINE JUST
WEST OF CMH TO ILN. THIS CONVECTION LINES UP PRETTY WELL WITH THE
LEADING WEAK UPPER LEVEL SHORTWAVE AS SEEN ON THE LATEST RAP RUN.
THE MAIN SHORTWAVE STILL LOOKS TO MOVE THROUGH AFTERNOON THROUGH
EVENING. UPDATED GRIDS BASED ON CURRENT RADAR AND OBSERVATIONS.
PREVIOUS DISCUSSION...
WARM FRONT OVER W EDGES OF FCST AREA EARLY THIS MORNING EXTENDS N
INTO NRN LOWER MI...WHERE IT IS OCCLUDED BY A COLD FRONT THAT
EXTENDS SW INTO THE MID MISSISSIPPI VALLEY. FIRST PROBLEM OF THE
DAY IS WHETHER PRECIPITATION WILL FIRE UP ALONG THE WARM FRONT EARLY
THIS MORNING AS IS TYPICAL THIS TIME OF DAY GIVEN A STRONG DEW POINT
/ THETA E GRADIENT IN THE LOWER LEVELS. NEAR TERM MODELS HAVE
BACKED OFF ON SAID DEVELOPMENT. LOW LEVEL CONVERGENCE ALONG THE
WARM FRONT IS SHALLOW...AND DISAPPEARS BY THE TIME ONE REACHES H85.
NONETHELESS...SCATTERED THUNDERSTORMS HAVE BEGUN TO FIRE EITHER SIDE
OF THE OHIO RIVER JUST W OF THE FCST AREA.
THE ABSENCE OF MORNING DEVELOPMENT WOULD ALLOW FOR ADDITIONAL
SURFACE HEATING TO FUEL AFTERNOON DEVELOPMENT OF CONVECTION AHEAD OF
AN UPPER LEVEL S/W TROUGH APPROACHING FROM THE W THIS
AFTERNOON...THE SECOND PROBLEM OF THE DAY. WITH THE SURFACE COLD
FRONT DISSIPATING...AND THE BEST UPPER LEVEL FORCING HEADED JUST N
OF THE FCST AREA...BEST INSTABILITY IS SHOWN W AND N OF THE FCST
AREA THROUGH SUNSET...KEEPING SEVERE THREAT TO A MINIMUM WITHIN THE
FCST AREA. FASTER STORM MOTION COMPARED WITH SATURDAY WILL ALSO
HELP TO MITIGATE THE FLOOD THREAT ASSOCIATED WITH SHOWERS AND
THUNDERSTORMS THIS AFTERNOON AND THIS EVENING.
THE SHOWERS AND THUNDERSTORMS MOVE ON E OVERNIGHT AND DIMINISH IN
AREA COVERAGE AFTER SUNSET...BUT AREAS OF FOG ARE LIKELY TO FORM
TONIGHT WHERE IT RAINS FROM THIS AFTERNOON ON.
WITH HIGH TEMPERATURES WITHIN THE SMALL ENVELOP OF GUIDANCE...AND
UNCERTAINTY AS TO PRECIPITATION DEVELOPMENT THIS MORNING AND HENCE
THE AMOUNT OF SUNSHINE TODAY...SAW LITTLE OR NO IMPROVEMENT
POTENTIAL ON HIGHS TODAY. DID EDGE LOWS TONIGHT UPWARD TOWARD
ADJMET GIVEN GUIDANCE ENVELOP OVERALL...DEW POINTS REMAINING HIGH
AND LESS THAN IDEAL RADIATIVE COOLING CONDITIONS.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
RIDGE ALOFT WILL REESTABLISH ITSELF OVER THE OHIO VALLEY WITH THE
BERMUDA HIGH AT THE SURFACE SETTING UP SIMULTANEOUSLY. LAST OF THE
UPPER LEVEL DISTURBANCES EXIT MONDAY...WITH A DRIER PATTERN
RETURNING FOR THE SHORT TERM. NAM...GFS...AND SREF COME INTO
AGREEMENT ON SOME ELEVATED HEAT SOURCE CONVECTION...SO WILL ADD LOW
POPS FOR THE MOUNTAINS IN THE AFTERNOONS AND EVENINGS TUESDAY AND
WEDNESDAY. MEANWHILE...THICKNESSES INCREASE IN THIS DEEP SUMMER
PATTERN...WITH WELL ABOVE NORMAL TEMPERATURES EXPECTED AREA WIDE
INTO THE MIDDLE OF THE WEEK. 925MB TEMPERATURES WILL CLIMB INTO THE
LOW TO MID 20S CELSIUS...TRANSLATING INTO LOWLAND 90S FAHRENHEIT.
SPECIFICS IN THESE AFTERNOON HIGH TEMPERATURES WILL DEPEND ON THE
RAINFALL OVER THE NEXT 36 TO 48 HOURS. IF LOCATIONS DO NOT GET
APPRECIABLE RAINFALL...MAY NEED TO ADD A COUPLE DEGREES TO THE MAX
TEMPERATURE FORECASTS TUESDAY AND WEDNESDAY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
MAIN STORY OF THE EXTENDED PERIOD IS THE RETURN TO SEASONABLE
TEMPERATURES WITH A PATTERN CHANGE AFTER A FEW MORE DAYS OF
UNCOMFORTABLE HEAT. AFTER HIGH PRESSURE DOMINATES THE MIDDLE PART OF
THE WEEK...MODELS ARE BEGINNING TO AGREE ON A WEAK COLD FRONT THAT
WILL USHER IN NW FLOW FOR THE END OF NEXT WEEK. STAYED CLOSE TO HPC
THINKING IN THIS PERIOD THAT UTILIZES A BLEND OF THE ECMWF AND GFS
ENS MEAN.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
PATCHY STRATOCU DECK AROUND THE AREA THIS MORNING WITH CIGS JUST
ABOVE 3 KFT IN SPOTS. BIGGER STORY IS SHOWERS AND THUNDERSTORMS
APPROACHING FROM THE W...WHICH COULD REACH VICINITY OF HTS AS EARLY
AS 14Z. AS THIS ACTIVITY MOVES INTO WV LATER THIS MORNING...IT WILL
TEND TO BREAK UP. HOWEVER...NEW THUNDERSTORMS WILL FIRE UP IN E
OHIO THIS AFTERNOON AND MOVE E ACROSS THE AREA LATER THIS AFTERNOON
AND TONIGHT. CODED UP SOME MVFR BUT OF COURSE...IFR WILL BE FOUND
RIGHT BENEATH ANY THUNDERSTORM.
FOG WILL FORM TONIGHT ANYWHERE IT RAINS LATER TODAY AND / OR TONIGHT
SO TOUGH TO PEG LOCATION ALTHOUGH DID HIT TYGART VALLEY HARD LATE
TONIGHT.
LIGHT SE SFC FLOW WILL BECOME LIGHT SW AS A WARM FRONT CROSSES THE
AREA THIS MORNING...AND THEN LIGHT S TO LIGHT AND VARIABLE TONIGHT.
FLOW ALOFT WILL BE LIGHT SW.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z MONDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: TIMING OF SHOWERS AND THUNDERSTORMS...AND
ASSOCIATED CIG AND VSBY RESTRICTIONS. SUCH RESTRICTIONS COULD OCCUR
MUCH EARLIER THIS MORNING ALONG THE OHIO RIVER DEPENDING UPON EXACT
MOVEMENT OF SHOWERS AND THUNDERSTORMS TO THE W. OF COURSE...TIMING
AND COVERAGE OF THUNDERSTORMS LATER TODAY AND TONIGHT COULD VARY.
THIS WILL ALSO EFFECT FORMATION OF POST-RAIN FOG TONIGHT.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
EDT 1HRLY 10 11 12 13 14 15 16 17 18 19 20 21
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H M H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H M M M
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z MONDAY...
NO WIDESPREAD AREAS OF IFR EXPECTED AT THIS TIME.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/26
NEAR TERM...TRM/MZ
SHORT TERM...26
LONG TERM...TAX
AVIATION...TRM
AREA FORECAST DISCUSSION
NWS PUEBLO CO
312 PM MDT SUN JUN 17 2012
.SHORT TERM...
(TONIGHT AND MONDAY)
THE MAIN CONCERN IS FIRE WEATHER ISSUES. THE FLOW ALOFT TODAY IS
WEST TO NW AND THE MTN AND HIGH VALLEY AREAS HAVE BEEN SEEING WIND
GUSTS THAT ARE MEETING CRITERIA FOR THE RED FLAG WARNING...AS ARE
THE RH VALUES. ON MONDAY THE FLOW ALOFT BECOMES WEST TO SOUTHWEST
AS AN UPR TROF MOVING INTO WRN MT...AND IT LOOKS LIKE WIND GUSTS
OVER THE MTS AND HIGH VALLEYS WILL AGAIN REACH RED FLAG
CRITERIA...AS WILL THE MIN RH VALUES. THUS WL UPGRADE THE FIRE
WEATHER WATCH THAT IS CURRENTLY IN EFFECT FOR THE MTS AND HIGH
VALLEYS...TO A RED FLAG WARNING.
THE NSSL 4KM WRF AND HRRR CONTINUE TO SHOW THE POTENTIAL FOR A
LITTLE CONVECTION NR THE SRN BORDER THRU ABOUT 00Z. HAVE
SEE A FEW ECHOES IN THE OK PANHANDLE...BUT WL KEEP POPS LESS THAN 15
PERCENT ALONG THE SRN BORDER FOR THE VERY EARLY EVENING HOURS.
OTHERWISE THE WEATHER WILL BE DRY ACRS THE FORECAST AREA TONIGHT.
MONDAY WILL BE ANOTHER HOT AND DRY DAY. H7 TEMPS IN THE AFTERNOON
ARE EXPECTED TO RANGE FROM 17C-21C. TEMPS ACRS THE SERN PLAINS WILL
BE IN THE UPPER 90S TO AROUND 103...WHILE THE HIGH VALLEYS SHOULD
SEE MID AND UPR 80S. THE RECORD HIGH FOR COLO SPGS MON IS 96...FOR
PUEBLO IS 104 AND FOR ALAMOSA IS 90. /28
.LONG TERM...
(MONDAY NIGHT THROUGH SUNDAY)
...CONTINUED HOT AND DRY...
EXTENDED FORECAST CONTINUES TO LOOK FAIRLY UNEVENTFUL...A TYPICAL
PRE-MONSOONAL SUMMERTIME PATTERN FOR THE ROCKIES. TUE SHOULD BE THE
LAST DAY OF POTENTIAL RECORD-BREAKING HEAT...AS H7 TEMPS REMAIN IN
THE 18-20 DEG C RANGE. FIRE WX DANGER WILL BE ELEVATED ON TUE...BUT
THERE IS STILL SOME QUESTION AS TO HOW STRONG SURFACE WINDS WILL BE
ON TUE...AND THAT WILL DETERMINE RED FLAG STATUS. THE NAM 12KM
SUGGESTS A FAIRLY BROAD LEE TROUGH WILL DEVELOP OVR THE AREA...AND
THE STRONGEST SFC GRADIENT WILL BE OVER W KS AND THE OK PANHANDLE.
THIS COULD KEEP WINDS FAIRLY LIGHT E OF THE MTS. HOWEVER...THERE IS A
STRONG JET TO OUR N...AND WITH DEEP MIXING EXPECT SOME STRONGER
GUSTS ESPECIALLY OVR WRN AND NRN PORTIONS OF THE CWA. WINDS SHOULD
STILL BE LIGHTER THAN ON MON...HOWEVER. WILL HOLD OFF ON ANY FIRE WX
HEADLINES FOR NOW.
FRONT SHOULD ARRIVE EARLY WED...AND TEMPS WILL FALL BACK
DRAMATICALLY ON WED AS H7 TEMPS FALL BACK BELOW 10 DEG C. COULD EVEN
SEE SOME UPPR 70S ON WED OVR THE PLAINS...FOR A PLEASANT REPRISE
FROM THE HEAT. THE PLEASANTRY WILL BE SHORT-LIVED...HOWEVER...AS A
TROUGH RELOADS ON THE W COAST FOR THE LATTER PART OF THE WEEK...AND
DRY AND HOT W-SW FLOW RESUMES. TEMPS COULD EASILY BE BACK INTO THE
UPPR 90S TO NEAR 100 BY THE END OF THE WEEK. VERY LITTLE IF ANY
PRECIP IS EXPECTED AS WELL. FORTUNATELY...THE GENERALLY LIGHT SFC
WINDS WILL LIMIT CRITICAL FIRE DANGER. THERE IS ALSO SOME INDICATION
THAT MID LEVEL MOISTURE WILL BEGIN MOVING NWD INTO THE S CENTRAL
ROCKIES FOR THE WEEKEND...BUT AT THIS POINT THE MOISTURE TAP LOOKS
MODEST AT BEST. DOG DAYS OF SUMMER APPEAR TO BE WITH US UNTIL FURTHER
NOTICE. ROSE
&&
.AVIATION...
VFR CONDITIONS WILL BE SEEN AT KCOS...KPUB AND KALS FOR THE NEXT 24
HRS. WIND GUSTS OF 15-25 KTS CAN BE EXPECTED AT KALS THRU ABOUT
01Z. KPUB AND KCOS WILL PROBABLY SEE GUSTS UP TO AROUND 20 KTS THRU
ABOUT 01Z. WINDS WILL PICK UP AGAIN ON MONDAY AFTERNOON WITH GUSTS
OF 15-25 KTS FROM THE SOUTH TO SOUTHWEST AT THE TAF SITES.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR COZ064-220>225.
RED FLAG WARNING FROM 11 AM TO 9 PM MDT MONDAY FOR COZ064-
220>225.
&&
$$
28/44
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1149 AM MDT SUN JUN 17 2012
.UPDATE...
ISSUED AT 1149AM MDT SUN JUN 17 2012
FORECAST SEEMS ON TRACK AS GUSTY WINDS IN THE HIGHER ELEVATIONS
AND HIGH VALLEYS CONTINUE TO MIX DOWN TO THE LOWER ELEVATIONS
OVER THE NEXT FEW HOURS. HIGHS ON TRACK WITH READINGS A FEW
DEGREES WARMER THAN THIS TIME YESTERDAY THE TREND OF 3 TO 5
DEGREES ABOVE SATURDAY/S HIGHS SHOULD HOLD. DRIER AIR IN PLACE
ALONG WITH NO APPARENT LIFTING MECHANISM SHOULD LEAVE ONLY A FEW
CLOUDS BUILDING OVER THE THE HIGH TERRAIN FOR MOSTLY SUNNY SKIES.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 246 AM MDT SUN JUN 17 2012
WINDS WILL START PICKING UP TODAY AS UPPER LEVEL FLOW BECOMES NWLY
DUE IN LARGE PART TO JET STREAM DROPPING DOWN OVER PACNW. NO
SHORTWAVES ARE IN THIS FLOW YET SO TODAY SUNNY SKIES WILL BE THE
RULE WITH TEMPERATURES REMAINING WELL ABOVE NORMAL. THE PRESSURE
GRADIENT WILL TIGHTEN AS DEEP MIXING ALSO OCCURS THIS
AFTERNOON...REACHING ABOUT 500MB OR SO. AS HAS BEEN ADVERTISED
MUCH OF THE WEEK...GUSTY WINDS ARE STILL EXPECTED WITH THE STRONGEST WINDS
NORTH OF INTERSTATE 70 THOUGH WINDS WILL ALSO PICK UP FOR AREAS
SOUTH. AS SUCH...THE RED FLAG WARNING CURRENTLY IN PLACE LOOKS GOOD SO
NO CHANGES WITH THIS PACKAGE.
BY TONIGHT...A PACIFIC CLOSED LOW SINKS SWRD INTO THE NWRN STATES WHILE
OVERALL TROF DEEPENS OVER THE GRT BASIN. THE DRY WESTERLY FLOW ALOFT
CONTINUES WITH POOR HUMIDITY RECOVERY CAUSING FWX CONCERNS. THE
UPPER LOW WILL THEN SHIFT EWRD INTO THE NRN ROCKIES MONDAY WHILE
THE TROF CONTINUES TO DIG FURTHER SWRD INTO THE GRT BASIN. AT THE
SAME TIME...THE JET SAGS SWRD INTO EXTREME NWRN UT AND CNTRL WY.
THIS CONTINUES TO RAISE FIRE CONCERNS AS DEEP MIXING WILL ALLOW MODERATE
WINDS ALOFT TO TRANSFER MOMENTUM TO THE SURFACE PRODUCING WIDE
SPREAD CRITICAL FWX CONDITIONS.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 246 AM MDT SUN JUN 17 2012
LITTLE CHANGE IS SEEN AS DRY CONDITIONS PREVAIL WITH A TROF OVER THE
WEST. ONE NOTABLE ITEM IS THAT THE SFC COLD FRONT/BAROCLINIC ZONE
ASSOCIATED WITH THE TROF MOVES EWRD TOWARD NE UT AND WRN WY MONDAY
NIGHT. THE TROF AXIS WILL THEN SHIFT EWRD TUESDAY AND WILL BE
CENTERED ALONG THE UT/CO BORDER. AT THE SAME TIME THE ABOVE
MENTIONED SFC FRONT WILL WASH OUT AND BECOME PRETTY DIFFUSE BEFORE
ENTERING OUR CWA TUESDAY NIGHT AS ENERGY PULLS OUT TO THE
NORTHEAST. TROF PASSAGE WILL OCCUR TUE NIGHT WITH LITTLE FANFARE
THOUGH HIGH TEMPS ON WED SHOULD BE ABOUT 5 DEGREES COOLER OR SO.
BY WEDNESDAY...HIGH PRESSURE WILL BUILD IN FROM THE DESERT SW
BUMPING THOSE HIGH TEMPS BACK TO THE MID-90S FOR MOST VALLEY
LOCATIONS AND AGAIN...NO PRECIPITATION. THIS TREND CONTINUES
THROUGH FRIDAY WHEN SOME MOISTURE FINALLY GETS ENTRAINED FROM THE
SOUTH...ACCORDING TO MOISTURE TRANSPORT VECTORS...ALBEIT STILL ON
THE LOW SIDE. WHILE THIS HAPPENS...A DEEPENING AREA OF LOW PRESSURE
OFF THE PACNW WILL ALSO CAUSE THE PRESSURE GRADIENT TO TIGHTEN.
DEEP MIXING WILL STILL BE OCCURRING DAILY SO SOME STRONGER WINDS
ARE EXPECTED FRIDAY AFTN/EVENING AND AGAIN SATURDAY POSSIBLY
CAUSING SOME FIRE WX CONCERNS. SWLY FLOW SHOULD ALLOW SOME SHOWERS AND
VERY ISOLATED STORMS TO FORM OVER THE DIVIDE FRIDAY BUT
AGAIN...ALL DEPENDENT ON AVAILABLE MOISTURE. EXPECT SIMILAR
WIND...AND SLT CHC FOR RAIN...ON SATURDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1149 AM MDT SUN JUN 17 2012
VFR CONTINUES ACROSS WESTERN COLORADO AND EASTERN UTAH UNDER
MOSTLY SUNNY SKIES. THE MAIN CONCERN WILL BE THE PRESENCE OF GUSTY WINDS
ACROSS THE REGION THIS AFTERNOON WITH GUSTS OVER 25 MPH IN MANY
AREAS INCLUDING THE FORECAST TERMINALS. SOME MECHANICAL
TURBULENCE WILL BE POSSIBLE OVER AND IN THE LEE OF THE RIDGE
LINES AS IS LOCALIZED LOW LEVEL WIND SHEAR IN THE VALLEYS. ANOTHER
CONCERN IS THE POSSIBILITY FOR SOME DENSE SMOKE NEAR THE LITTLE
SAND FIRE TO THE NW OF PAGOSA SPRINGS. VIS MAY DROP IN AND AROUND
THE FIRE TO MVFR...IF NOT IFR CONDITIONS FROM MID ELEVATIONS DOWN
INTO THE VALLEYS MAINLY DURING THE LATE EVENING THROUGH MID
MORNING HOURS WHEN VENTILATION IS POOR.
&&
.FIRE WEATHER...
ISSUED AT 1149 AM MDT SUN JUN 17 2012
RED FLAG WARNING REMAINS IN EFFECT TODAY FROM NOON UNTIL 9 PM. A FEW
RAWS SITES WERE ALREADY HITTING CRITERIA IN THE TAVAPUTS AND ROAN
PLATEAUS AT 11 AM. HIGH RESOLUTION HRRR AND RAP MODELS INDICATE WIND
GUSTS WILL CONTINUE TO DEVELOP TODAY. INTERESTINGLY...THE HRRR MODEL
SHOWED SOMEWHAT OF A LOCAL MINIMA DEVELOPING FOR ZONES 290/292. NOT
SURE WHY GUSTS WOULD LESSEN DURING PEAK HEATING THIS AFTERNOON SO
DISCOUNTED THIS.
THE FIRE WEATHER WATCH CONTINUES FOR MONDAY WITH BONE DRY CONDITIONS
AND HOT TEMPS FOR DEEP MIXING TO TAP STRENGTHENING FLOW ALOFT ACROSS
THE NORTH. A WEAK DISTURBANCE MOVING ACROSS SW CO MONDAY AFTERNOON
MAY HELP STIR THINGS UP DESPITE WEAKER WINDS ALOFT. STILL QUESTIONS
ON THE TIMING AND STRENGTH OF A COLD FRONT MOVING IN FROM THE NW ON
TUESDAY. AN INITIAL PEEK AT THE 12Z NAM/GFS LOOKS A LITTLE LESS
FAVORABLE FOR WIDESPREAD CRITICAL CONDITIONS ON TUESDAY...THOUGH...
ESPECIALLY ACROSS SW CO. WILL CONTINUE TO EVALUATE.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR COZ200>203-207-
290>293.
FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY EVENING
FOR COZ200>203-207-290>293.
UT...RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR UTZ481>487.
FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY EVENING
FOR UTZ481>487.
&&
$$
UPDATE...15
SHORT TERM...TGR/MC
LONG TERM...TGR/MC
AVIATION...15
FIRE WEATHER...JAD
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
204 PM EDT SUN JUN 17 2012
.SYNOPSIS...
18Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS A SIMILAR PICTURE TO THE
ONE FROM 24 HOURS AGO. THE FORECAST AREA REMAINS IN BETWEEN AN UPPER
LEVEL RIDGE ACROSS THE WESTERN GULF OF MEXICO/LOWER MS VALLEY AND A
LARGE ATLANTIC TROUGH/CLOSED LOW SPINNING SEVERAL HUNDRED MILES
EAST OF THE CAROLINA COAST. OUR POSITION ON THE WESTERN PERIPHERY OF
THIS TROUGH IS PROVIDING A DEEP LAYER NORTHERLY FLOW OVER THE
PENINSULA. ALTHOUGH SOME SLIGHT MOISTURE ADVECTION IN THE UPPER
LEVELS HAS BEEN NOTED IN WV THIS MORNING WITHIN THIS NORTHERLY
FLOW...THE OVERALL COLUMN REMAINS QUITE DRY. 12Z KTBW SOUNDING
PROFILE MEASURED A PW VALUE OF AROUND AN INCH. THIS VALUE IS ONLY
AROUND 65% OF CLIMATOLOGY FOR MID JUNE. THE DRIER AIR IS PROVIDING
FOR AN OVERALL HOSTILE ENVIRONMENT FOR DEEP CONVECTION WITH
700-500MB THETA-E VALUES MEASURED BETWEEN 316-319K. TYPICAL VALUES
FOR THIS TIME OF YEAR TO SUPPORT SUSTAINED DEEP CONVECTION RUN
BETWEEN 323-329K.
AT THE SURFACE...1022MB HIGH PRESSURE CENTERED OVER THE CAROLINAS
CONTINUES TO RIDGE SOUTHWARD OVER THE FL PENINSULA AND EASTERN GULF.
THE GRADIENT IS RATHER TIGHT RESULTING IN A BREEZY E/NE FLOW. THIS
GRADIENT IS EXPECTED TO WEAKEN SLIGHTLY THIS AFTERNOON...WHICH MAY
ALLOW FOR SOME FEEBLE SEA-BREEZE DEVELOPMENT. HOWEVER...THE SYNOPTIC
FLOW ONLY 1500-2000 KFT ABOVE THE SURFACE HOLDS EAST AT 10-15 KTS
THROUGH THE AFTERNOON. THIS SHOULD BE ENOUGH TO KEEP ANY WEAK
SEA-BREEZE CIRCULATION PINNED AT THE BEACHES OR EVEN SLIGHTLY
OFFSHORE.
.SHORT TERM (REST OF TODAY - TUESDAY)...
WITH LITTLE TO NO INLAND PENETRATION OF ANY FEEBLE SEA-BREEZE...
COMBINED WITH THE MID-LEVEL ENVIRONMENT...CONVECTIVE COVERAGE
THROUGH MID EVENING SHOULD BE BELOW CLIMATOLOGY. STILL CAN NEVER
RULE OUT A FEW ISOLATED CELLS DEVELOPING...ESPECIALLY CLOSE TO THE
COAST WHERE SOME LOW LEVEL FOCUS FOR UPDRAFTS MAY BECOME ESTABLISHED
IN THE NEXT SEVERAL HOURS. SIMILAR TO SATURDAY...ANY CELLS THAT DO
TRY TO DEVELOP WILL ENCOUNTER AND ENTRAIN THE UNFAVORABLE MID-LEVEL
AIR...AND LIKELY DECAY RAPIDLY. CURRENTLY HAVE A SLIGHT CHANCE
15-20% POP IN THE GRIDS STARTING AFTER 18Z...AND FEEL THIS SHOULD
HANDLE THE SITUATION.
ANY ISOLATED STORMS EARLY THIS EVENING NEAR THE COAST SHOULD PUSH
OFFSHORE WITH THE SYNOPTIC FLOW AFTER 00-02Z. THE REST OF THE
OVERNIGHT LOOKS DRY AND SEASONABLE COOL. ONCE AGAIN MANY INLAND
SPOTS WILL BOTTOM OUT IN THE 60S BY SUNRISE MONDAY MORNING.
MONDAY THROUGH TUESDAY...
UNSEASONABLE DRY CONDITIONS FOR LATE JUNE WILL BE THE RULE DURING
THE FIRST PART OF THE WORK WEEK. UPPER LEVEL TROUGH OVER THE WESTERN
ATLANTIC WILL SHIFT EASTWARD WITH TIME ALLOWING HEIGHT RISES/UPPER
LEVEL RIDGING TO BUILD OVER THE PENINSULA. LATEST GUIDANCE INDICATES
THAT THE ATMOSPHERIC COLUMN WILL REMAIN AS HOSTILE IF NOT MORE
HOSTILE THAN TODAY THROUGH TUESDAY...ESPECIALLY CONSIDERING THE
ADDED SUPPRESSION FORM THE BUILDING UPPER RIDGE. THETA-E VALUES
BETWEEN 700-600MB ARE VERY LOW FOR THIS TIME OF YEAR WITH SOME
GUIDANCE MEMBERS DROPPING VALUES BELOW 315K. INHERITED FORECAST FROM
LAST NIGHT SHOWED ONLY SILENT 10% RAIN CHANCES IN THE GRIDS...AND
SEE LITTLE REASON TO MAKE ANY SIGNIFICANT CHANGES. AN ISOLATED CELL
OR 2 IS LIKELY TO TAKE ROOT SOMEWHERE...HOWEVER COVERAGE WILL BE
VERY LOW. DAYTIME TEMPERATURES WILL BE SEASONABLE IN THE LOWER
90S...HOWEVER A WELL MIXED BOUNDARY LAYER EACH AFTERNOON SHOULD KEEP
DEWPOINT IN A "COMFORTABLE" RANGE FOR THIS TIME OF YEAR. ANOTHER
COOL NIGHT MONDAY NIGHT WITH MANY LOCATIONS AGAIN DROPPING INTO THE
MID/UPPER 60S AWAY FROM THE COAST...FOLLOWED BY A SLOW MODERATION
TREND BEGINNING TUESDAY NIGHT.
&&
.LONG TERM (WEDNESDAY - SATURDAY)...
SURFACE HIGH PRESSURE WILL HOLD OVER THE MID ATLANTIC COAST
WEDNESDAY AND THURSDAY WITH EASTERLY BOUNDARY LAYER FLOW ACROSS THE
FORECAST AREA. STRONG U/L RIDGE OVER THE EASTERN U.S. WEDNESDAY
WILL WEAKEN THURSDAY AS A STRONG U/L TROUGH IN THE MAIN WESTERLY
FLOW ACROSS THE NORTHERN TIER OF THE U.S. RIDES OVER AND SUPPRESSES
THE RIDGE. THE U/L RIDE WILL RE-ESTABLISH ITSELF FRIDAY AND
SATURDAY OVER THE SOUTHEAST U.S. AND FLORIDA. GFS AND ECMWF COMING
MORE IN LINE WITH ANY SURFACE LOW DEVELOPMENT IN THE GULF OF MEXICO
BEING OVER THE SOUTHWEST OR WESTERN GULF. THIS WILL KEEP WEST
CENTRAL AND SOUTHWEST FLORIDA UNDER THE INFLUENCE OF THE U/L RIDGE
WITH STRONG SUBSIDENCE AND RELATIVELY DRY HOT CONDITIONS...WITH
EASTERLY BOUNDARY LAYER FLOW CONTINUING. THE U/L RIDGE WILL
SUPPRESS A TROUGH OF LOW PRESSURE ACROSS THE FLORIDA STRAITS THROUGH
THE WEEK WITH THE DEEP TROPICAL MOISTURE REMAINING SOUTH OF THE
FORECAST AREA. MAIN UNCERTAINTY IN THE FORECAST IS HOW LONG WILL
THE DEEP MOISTURE REMAIN SUPPRESSED TO THE SOUTH. BUT INCREASED
CONFIDENCE IN THE EXTENDED FORECAST THAT TEMPERATURES WILL RUN ABOVE
CLIMATIC NORMALS WITH RELATIVELY DRY CONDITIONS.
&&
.AVIATION...
MAINLY VFR NEXT 24 HOURS. A FEW LIGHT SHOWERS COULD BRIEFLY AFFECT
TERMINALS THIS AFTERNOON...BUT COVERAGE TOO LOW FOR MENTION.
&&
.MARINE...
HIGH PRESSURE TO OUR NORTH WILL KEEP A GENERAL EASTERLY FLOW IN
PLACE FOR THE NEXT COUPLE OF DAYS. THIS HIGH SETUP WILL CONTINUE TO
BE FAVORABLE FOR NOCTURNAL WIND SURGES. WINDS ARE EXPECTED TO
INCREASE TO CAUTIONARY LEVELS OVERNIGHT TONIGHT AND POTENTIALLY ONCE
AGAIN MONDAY NIGHT.
&&
.FIRE WEATHER...
A STRONG RIDGE OF HIGH PRESSURE WILL CONTINUE TO
PROVIDE A WARM AND DRY EAST TO NORTHEAST FLOW ACROSS THE REGION FOR
THE NEXT COUPLE OF DAYS. RELATIVE HUMIDITIES MAY APPROACH 35 PERCENT
MONDAY AFTERNOON ALONG WITH HIGH DISPERSIONS. MOISTURE WILL BEGIN TO
RETURN FROM THE SOUTH TOWARD THE END OF THE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 71 90 72 92 / 10 10 10 10
FMY 70 91 71 92 / 10 10 10 10
GIF 68 91 70 92 / 10 10 10 10
SRQ 69 91 71 93 / 10 10 10 10
BKV 66 91 66 91 / 10 10 10 10
SPG 75 90 74 91 / 10 10 10 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/MARINE...MROCZKA
LONG TERM...OGLESBY
AVIATION/FIRE WEATHER...JILLSON
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1214 PM CDT SUN JUN 17 2012
.DISCUSSION...
ISSUED 1012 AM CDT SUN JUN 17 2012
A FEW BOUNDARIES CONTINUE TO LOITER ACROSS THE AREA FROM OVERNIGHT
CONVECTION. BEST ESTIMATE OF THE ACTUAL SURFACE FRONT...WHICH IS
MORE OF A DEW POINT DISCONTINUITY...IS FROM QUINCY TO THE NORTHEAST
TIP OF ILLINOIS. HAD SOME LOW CLOUDS FORM IN THE RAINIER AREAS
ACROSS THE ILLINOIS RIVER VALLEY...WITH LATEST OBSERVATIONS AND
SATELLITE IMAGERY SHOWING THEM LINGERING FROM AROUND PEORIA TO
CHAMPAIGN AND DANVILLE. AREAS SOUTHEAST OF I-70 ALSO SEEING QUITE
A BIT OF CLOUDS BELOW 1500 FEET.
MAIN QUESTION FOR TODAY IS POTENTIAL FOR CONVECTIVE REDEVELOPMENT.
LATEST RAP MODEL SHOWING SUBSIDENCE OVERSPREADING THE AREA FROM
THE NORTH THIS AFTERNOON...SUPPRESSING ANY CUMULUS. RAP...HRRR AND
NAM MODELS SUGGEST DEVELOPMENT IN AN AREA WHERE DEWPOINTS POOL IN
THE LOWER 70S...GENERALLY FROM CENTRAL MISSOURI INTO SOUTHERN
ILLINOIS. BULK OF THIS APPEARS TO BE JUST SOUTH OF OUR FORECAST
AREA...BUT CLOSE ENOUGH TO JUSTIFY MENTIONING SOME ISOLATED
SHOWERS/STORMS IN THE SOUTHEAST CWA.
HAVE ALSO MADE SOME MINOR ADJUSTMENTS TO THE TEMPERATURES ACROSS
THE NORTH...WHERE THE CLOUDS HAVE SLOWED THE DIURNAL TEMPERATURE
RISE. UPDATED ZONES/GRIDS HAVE BEEN SENT.
GEELHART
&&
.AVIATION...
ISSUED 1213 PM CDT SUN JUN 17 2012
MVFR CEILINGS LINGERING EAST OF A KBMI-KDEC LINE AT MIDDAY.
VISIBLE SATELLITE IMAGERY CONTINUES TO SHOW STEADY EROSION AS AN
AREA OF DRIER AIR PUSHES INTO THE STATE FROM THE NORTHWEST. KCMI
MOST LIKELY TO SEE CEILINGS BELOW 3000 FT FOR ANOTHER HOUR OR TWO.
LATEST NAM MODEL SHOWING LOW LEVEL JET RAMPING UP OVERNIGHT JUST
TO OUR WEST. HAVE SOME CONCERNS ABOUT A COUPLE HOURS OF LLWS
POTENTIAL TOWARD SUNRISE ACROSS THE WESTERN TAF SITES...BUT WILL
LEAVE OUT FOR NOW AS CONDITIONS ARE STILL A BIT BORDERLINE IN OUR
AREA. WILL SEE THESE WINDS ALOFT MIX DOWN TO THE SURFACE ON
MONDAY...WITH GUSTS OF 25-30 KNOTS LIKELY BY LATE MORNING. THE
HIGHEST GUSTS ARE EXPECTED JUST BEYOND THE CURRENT FORECAST
PERIOD.
GEELHART
&&
.PREV DISCUSSION...
ISSUED 330 AM CDT SUN JUN 17 2012
SHORT TERM...TODAY THROUGH WEDNESDAY
MCS WEAKENING OVER EASTERN AND SOUTHERN IL EARLY THIS MORNING
WITH SCATTERED SHOWERS EAST OF HIGHWAY 51. THUNDERSTORMS MAINLY
CONFINED TO SOUTHERN MO INTO SW IL SOUTH OF I-64 AND WEST OF I-57.
MCS WAS AHEAD OF COLD FRONT PRESSING SE INTO SE WI AND FAR NW IL.
MUGGY DEWPOINTS OF 65 TO 70F ACROSS MUCH OF CENTRAL AND SE IL.
00Z MODELS CONTINUE TO TREND FURTHER SOUTH WITH CONVECTION CHANCES
TODAY AND LESS CLOUD COVER OVER CENTRAL IL TODAY...AND MAINLY CONFINED
20-40% CHANCES OF SHOWERS AND THUNDERSTORMS TO SOUTHEAST IL AS COLD
FRONT SWEEPS SE THROUGH CENTRAL IL THIS MORNING AND WEAKENS INTO
SE IL THIS AFTERNOON. SPC DAY1 OUTLOOK DOES NOT HAVE A SLIGHT RISK
OVER SE IL TODAY...WITH 5% AREA SE OF I-70 FOR DAMAGING WIND GUSTS
THIS AFTERNOON AND EARLY EVENING UNTIL SUNSET MAINLY DUE TO SOME
INSTABILITY WITH CAPES PEAKING NEAR 2000 J/KG THIS AFTERNOON.
FRONTAL BOUNDARY LIFTING BACK NORTH TONIGHT HAS LIMITED LIFT ALONG
IT SO JUST ISOLATED SHOWERS AND THUNDERSTORMS POSSIBLE. HIGHS
MOSTLY IN THE UPPER 80S TODAY WITH LAWRENCEVILLE NEAR 90F AND STAYING
HUMID IN SE IL WHILE BECOMING LESS HUMID OVER CENTRAL IL BEHIND
THE FRONT.
STRONG UPPER LEVEL RIDGE BUILDING OVER THE MID MS AND OHIO VALLEYS
MON THROUGH WED TO RETURN HOT AND DRY WEATHER TO CENTRAL AND SE IL
WITH HIGHS IN THE LOW TO MID 90S. STORM TRACK TO REMAIN NORTH OF
IL DURING THIS TIME OVER MN AND CENTRAL AND NW PARTS OF IA/WI.
MODELS CONTINUE TO INCREASE WIND SPEEDS EARLY THIS WORK WEEK
ESPECIALLY MON WITH TIGHTER PRESSURE GRADIENT AND HAVE SSW WIND
GUSTS OF 30 TO 40 MPH MON AFTERNOON.
LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY
LOW PRESSURE EJECTING NE INTO ONTARIO WED NIGHT/THURSDAY TO DRIVE
A COLD FRONT SE INTO IL THU. THIS TO RETURN A CHANCE OF SHOWERS
AND THUNDERSTORMS AND SHIFTING MORE INTO SOUTHERN IL FRIDAY. TEMPS
COOL BACK TO NORMAL LATE THIS WEEK WITH HIGHS IN THE MID TO UPPER
80S FRI/SAT. BUT SOME MODELS LIKE THE 00Z ECMWF SHOW STRONG UPPER
LEVEL RIDGE MOVING BACK INTO THE MID MS VALLEY BY NEXT SUNDAY
WHICH WOULD RETURNING HOTTER TEMPERATURES.
KH
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CARIBOU ME
620 PM EDT SUN JUN 17 2012
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN ACROSS THE REGION INTO THE FIRST PART OF
THE WEEK. THIS HIGH WILL SLIDE OFF TO THE EAST TUESDAY WITH A WEAK
COLD FRONT GRAZING THE REGION TUESDAY NIGHT BEFORE LIFTING BACK TO
THE NORTH BY LATE WEDNESDAY AS A WARM FRONT.
&&
.NEAR TERM /THROUGH MONDAY/...
620 PM UPDATE: FORECAST ON TRACK SO NO CHANGES NEEDED AT THIS TIME.
FOG AND STRATUS STILL LOOKS POSSIBLE AFTER MIDNIGHT FOR DOWNEAST.
BOTH HRRR AND REG GEM MODELS INDICATE AREA OF FOG CURRENTLY
BETWEEN CAPE COD AND YARMOUTH NOVA SCOTIA WILL MOVE NORTHWARD
REACHING THE COAST AROUND 2AM MONDAY MORNING AND THEN MOVE AS FAR
NORTH AS THE BANGOR AREA. FOR THE REMAINDER OF THE REGION, PATCHY
RADIATIONAL FOG POSSIBLE BETWEEN 3AM AND 6AM MONDAY MORNING.
PREVIOUS DISCUSSION:
A RIDGE OF HIGH PRESSURE WILL REMAIN DOMINANT ACROSS THE REGION
THROUGH MONDAY WITH TRANQUIL WEATHER CONTINUING AS A RESULT. THE
ONE CONCERN WILL BE FOR TONIGHT AS THERE WILL BE THE POTENTIAL FOR
SOME LOW CLOUDS AND FOG TO COME IN FROM THE EAST AND AFFECT MAINLY
COASTAL AREAS, ALTHOUGH SOME PATCHY RADIATIONAL FOG MAY ALSO FORM
INLAND ACROSS THE REMAINDER OF THE CWA. ANY FOG/CLOUDS THAT FORM
WILL DIMINISH TOMORROW MORNING WITH PARTLY TO MOSTLY SUNNY SKIES
EXPECTED FOR THE AFTERNOON. HIGHS WILL RANGE FROM THE UPPER 70S IN
THE NORTH TO THE 65-70 RANGE DOWNEAST DUE TO AN ONSHORE FLOW.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
THE SURFACE AND UPPER RIDGES REMAIN IN PLACE FOR TUESDAY NIGHT. A
SOUTHERLY FLOW WILL ADVECT LOW STRATUS AND AREAS OF FOG NORTHWARD
DURING THE NIGHT. THIS WILL BE THE LAST COOL NIGHT FOR SEVERAL
DAYS WITH LOWS IN THE UPPER 40S TO LOW 50S...WITH THE ALLAGASH
ACTUALLY EXPERIENCING THE UPPER RANGE OF THESE TEMPERATURES. THE
FOG AND STRATUS AND BURN OFF TUESDAY MORNING...BUT THE SOUTHERLY
FLOW WILL KEEP LIMIT HIGHS TO THE MID 60S ALONG THE COAST AND LOW
70S FOR MUCH OF DOWN EAST TO INCLUDE BANGOR. THE WARMER
TEMPERATURES WILL BE FURTHER NORTH WITH LOW TO MID 80S FOR THE
ALLAGASH AND SJV. A COLD FRONT BRINGS THE RISK OF A THUNDERSTORM
TO THE NW CORNER OF THE STATE BY LATE AFTERNOON. THE BEST ENERGY
WITH THIS COLD FRONT WILL BE FAR TO THE NORTH AND THE UPPER RIDGE
WILL QUICKLY REBUILD FOR WEDNESDAY. AS A RESULT...WILL ONLY GO
WITH SLIGHT CHANCE POPS FOR THUNDERSTORMS TUESDAY NIGHT. FOG AND
STRATUS WILL RETURN DOWN EAST OVERNIGHT. WARM AIR ADVECTION WILL
PRODUCE LOWS IN THE MID TO UPPER 60S IN THE ALLAGASH AND MUCH
COOLER LOWS DOWN EAST WHERE MID TO UPPER 50S ARE EXPECTED WITH THE
CONTINUING MARINE LAYER AND SOUTHERLY FLOW.
THE COLD FRONT WILL NOT PASS THROUGH THE STATE OR BRING ANY
COOLER AIR FOR WEDNESDAY. INSTEAD...IT WILL ONLY PRODUCE A DRIER
WESTERLY WIND AND ALLOW TEMPERATURES TO CLIMB WELL INTO THE MID TO
UPPER 80S ACROSS THE FORECAST AREA. SOME LOW 90S ARE POSSIBLE FOR
INTERIOR DOWN EAST. HAVE GONE WITH A BLEND OF ECMWF/GFS/NAM
GUIDANCE FOR WEDNESDAY. THIS RESULTED IN JUST SOME SLIGHT CHANCE
POPS IN THE MORNING LEFTOVER FROM THE FRONT AND OTHERWISE DRY.
HOWEVER...THE GENERAL POSITION OF THE UPPER LEVEL HIGH AND A
FRONTAL BOUNDARY TO THE NORTH BRINGS SOME CONCERN ABOUT AN MCS
TYPE OF FEATURE MOVING SOUTHEAST OUT OF QUEBEC LATER WEDNESDAY AND
WEDNESDAY NIGHT AND THIS WILL BE SOMETHING TO WATCH. HAVE GONE
WITH SLIGHT CHANCE POPS FOR THUNDERSTORMS WEDNESDAY EVENING TO
REFLECT THIS RISK.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
THE WARM AIR CONTINUES WEDNESDAY NIGHT WITH LOWS IN THE 65 TO 70F
RANGE AND A POTENTIALLY EVEN WARMER DAY ON THURSDAY WITH UPPER 80S
AND LOW 90S. A MORE VIGOROUS COLD FRONT ARRIVES THURSDAY AFTERNOON
WITH THUNDERSTORMS. THE BEST CHANCE FOR THE THUNDERSTORMS WILL BE
NORTH OF HOULTON...BUT CANNOT RULE OUT STORMS ALL THE WAY DOWN TO
THE COAST. THIS FRONT WILL FINALLY BRING SOME COOLER TEMPERATURES
AND LOWER HUMIDITY. HIGHS FRIDAY WILL DROP TO THE MID 70S NORTH
AND NEAR 80F DOWN EAST AND EVEN LOWER FOR SATURDAY WITH NW WINDS.
ANOTHER FRONT IS PROGGED FOR SUNDAY.
&&
.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
NEAR TERM: THERE IS A GOOD POTENTIAL FOR SOME LOW CLOUDS AND FOG
TO DEVELOP AND MOVE IN FROM THE SOUTH TONIGHT AND AFFECT KBGR AND KBHB
BEFORE BURNING OFF TOMORROW MORNING. A PERIOD OF IFR CONDITIONS IS
LIKELY TONIGHT INTO EARLY TOMORROW FOR THESE AREAS AS A RESULT.
ALSO EXPECT POTENTIAL FOR IFR ACROSS THE NORTHERN SITES LATE
TONIGHT / EARLY TOMORROW DUE TO PATCHY RADIATIONAL FOG.
SHORT TERM: IFR MONDAY NIGHT...WITH SOME VLIFR POSSIBLE FOR BGR AND
BHB. THESE CONDITIONS WILL CONTINUE EARLY TUESDAY AND RETURN FOR
DOWN EAST LOCATIONS ON TUESDAY NIGHT. VFR IS EXPECTED WEDNESDAY
INTO FRIDAY...OUTSIDE OF THUNDERSTORMS WEDNESDAY NIGHT AND
THURSDAY EVENING.
&&
.MARINE...
NEAR TERM: WINDS/SEAS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT
ADVISORY LEVELS MONDAY. HOWEVER VISIBILITIES COULD BE REDUCED IN
AREAS OF FOG LATE TONIGHT INTO MONDAY MORNING.
SHORT TERM: FOG IS EXPECTED MONDAY NIGHT THROUGH TUESDAY NIGHT.
REDUCED VISIBILITY SHOULD CONTINUE WELL INTO THURSDAY IN THE FORM
OF HAZE AND FOG. WAVE HTS ARE EXPECTED TO INCREASE LATE TUESDAY IN
A SOUTHERLY SWELL REACHING 4 OR EVEN 5 FEET.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...FITZSIMMONS/FOSTER
SHORT TERM...MCW
LONG TERM...HEWITT
AVIATION...FITZSIMMONS/FOSTER
MARINE...FITZSIMMONS/FOSTER/MCW
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
141 PM EDT SUN JUN 17 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 521 AM EDT SUN JUN 17 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A SHORTWAVE TROF FROM NRN
MANITOBA TO THE UPPER GREAT LAKES BEGINNING TO BE FORCED NE DUE TO
RIDGE EXTENDING FROM THE OHIO VALLEY TO QUEBEC. STRONG SURGE OF
DRIER AIR IS FOLLOWING SHORTWAVE PER 00Z SOUNDINGS WHICH SHOWED
PRECIPITABLE WATER DOWN BLO ONE-HALF INCH OVER THE DAKOTAS.
IMPRESSIVELY DRY AIR WAS NOTED BTWN ROUGHLY 700-500MB ON 00Z
KINL/KBIS SOUNDINGS. DWPT DEPRESSIONS WERE WELL IN EXCESS OF 30C.
KBIS SOUNDING ALSO SHOWED A DRY WELL-MIXED BOUNDARY LAYER. THIS IS
THE AIR MASS THAT WILL BE QUICKLY SHIFTING ACROSS THE AREA TODAY...
RESULTING IN A WARM DAY WITH COMFORTABLE HUMIDITY LEVELS. MIXING TO
800-750MB ON FCST SOUNDINGS YIELDS MAX TEMPS IN THE MID 70S TO LWR
80S. WEAKENING WRLY BOUNDARY LAYER FLOW THIS AFTN WILL ALLOW LAKE
BREEZE DEVELOPMENT TO PROVIDE SOME AFTN COOLING NEAR THE GREAT
LAKES. DRY AIR AVBL TO MIX DOWN SHOULD RESULT IN SFC DWPTS FALLING
TO THE UPPER 40S/LWR 50S IN GENERAL AWAY FROM LAKE MODIFICATION.
SOME LOW/MID 40S NOT OUT OF THE QUESTION GIVEN MAGNITUDE OF DRY AIR
ALOFT. SUN WILL MIX WITH HIGHER BASED CU DURING THE DAY.
AS FAST AS THE DRYING OCCURRED TODAY...MOISTURE WILL QUICKLY RETURN
TONIGHT ON STRENGTHENING SW FLOW IN RESPONSE TO SHORTWAVE ENERGY
RACING ACROSS THE NRN PLAINS. 850MB THETA-E ADVECTION/MOISTURE
ADVECTION IS IMPRESSIVE TONIGHT AS LOW-LEVEL JET RAMPS UP TO 40-50KT
AND TAKES AIM AT UPPER MI. WHILE BEST MUCAPE TO THE SW SHOULD RESULT IN
STRONGER CONVECTION OCCURRING TO THE SW/S AND THUS INTERCEPTING SOME
OF THE MOISTURE TRANSPORT TO UPPER MI...OVERALL DEGREE OF DEEP LAYER
FORCING TO THE N AND BUILDING 850-300MB THICKNESS RIDGE FARTHER N
WITH TIME SUGGEST CONVECTIVE DEVELOPMENT SHOULD EXTEND N AND NE WITH
TIME AS WELL. WITH EXPECTATION OF STRONGER CONVECTION TO THE S/SW
INTERCEPTING INSTABILITY TRANSPORT...NOT ANTICIPATING ANY SVR STORMS
TONIGHT. HOWEVER...SHOULD STRONGER STORMS TO THE S/SW WEAKEN...
ADVECTION OF INSTABILITY TO THE NE COMBINED WITH MARGINAL EFFECTIVE
DEEP LAYER SHEAR COULD LEAD TO SOME HAIL PRODUCING STORMS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 521 AM EDT SUN JUN 17 2012
EXPECT A GOOD CHANCE OF SHOWER AND THUNDERSTORM ACTIVITY MOST
PERIODS THROUGH WEDNESDAY NIGHT...ALONG WITH PATCHY FOG OVER
PORTIONS OF LAKE SUPERIOR. WE BEGIN THE PERIOD WITH W/SW FLOW AT
500MB...WITH HIGH PRESSURE BUILDING ACROSS THE MID ATLANTIC STATES
AND A SERIES OF WAVES SLIDE ACROSS OR NORTH OF UPPER MI.
WILL LOOK FOR A POTENTIAL MCS TO PUSH ACROSS THE AREA MONDAY
AFTERNOON INTO THE EVENING HOURS...AS THE NEARING SFC LOW SHIFTS FROM
THE EASTERN DAKOTAS AT 06Z MONDAY AND CROSSES MN MONDAY AFTERNOON
BEFORE EJECTING ACROSS LAKE SUPERIOR AND ONTARIO. CONTINUE TO
HIGHLIGHT STRONG WINDS AND HAIL THREAT IN THE HWO. EXPECT STRONG
WINDS JUST OFF THE SFC FROM 4-13Z MONDAY W...08-17Z MONDAY S CENTRAL
/SLIGHTLY LESS PRONOUNCED AND SLOWER OFF THE GFS/...AND MORE LIKE 12Z
MON-00Z TUE E...IN THE 50-60KT RANGE. LLWS WILL BE LIKELY A THREAT
FOR FOR AVIATION USERS...WITH STRONG WINDS JUST ABOVE THE SFC AND
ALOFT. EXPECT DCAPE VALUES NEAR 1K J/KG NEAR THE WI BORDER BY
18Z...WITH STRONG WINDS BEING A POSSIBILITY WITH ANY TSRA THAT
DEVELOPS. 0-2KM LAPSE RATES LOOK TO TOP OUT AROUND 6-7C/KM...WITH A
THIN LINE UP TO AROUND 8C/KM OVER THE INTERIOR W HALF OF UPPER MI BY
00Z TUESDAY...LINING UP WITH 1K-2K J/KG CAPE VALUES. EVEN THE 0-3KM
CAPE IS 0.5-1K J/KG OVER THE W HALF BY 18Z...WITH A CONTINUATION
CENTRAL AND E THROUGH 00Z TUE. CIN LOOKS TO BE AOB 40 J/KG OVER THE
INTERIOR W HALF...WITH AN INDICATION OF ELEVATED STORMS CENTRAL AND E
OF A LINE FROM ALGER TO DELTA COUNTY AT LEAST INITIALLY. EXPECT TO
SEE STRONGER STORMS NEARING FROM THE WSW...TO DIMINISH AS THEY PUSH
INTO THE LESS FAVORABLE AREAS OF CENTRAL AND E UPPER MI.
WHILE THE COLD FRONT BRIEFLY SINKS JUST SE OF THE CWA MONDAY
NIGHT...IT WILL RETURN IN THE FORM OF A WARM FRONT TUESDAY
AFTERNOON...IN RESPONSE TO THE NEXT SFC LOW EDGING ACROSS MN FROM
THE CENTRAL PLAINS. CAPE VALUES AGAIN NEAR 1K J/KG TUESDAY AS THIS
LOW TOO PUSHES ACROSS W LAKE SUPERIOR AND INTO ONTARIO TUESDAY NIGHT
INTO EARLY WEDNESDAY. ATTEMPTED TO DRY OUT AREAS NEAR LAKE MI
TUESDAY NIGHT...OUT AHEAD OF THE APPROACHING COLD FRONT. TIMING OF
THE COLD FRONT IS A BIT TRICKY...BUT SHOULD BE OVER THE W THIRD OF
THE CWA BY AT LEAST 18Z WEDNESDAY. COMPARING MODEL OUTPUT...THE
17/06Z NAM IS ON THE QUICK END OF MODEL SOLUTIONS AT LEAST SFC
WISE...WITH THE 17/00Z RUN OF THE CANADIAN AT LEAST 12 HOURS BEHIND
THE NAM. THE GFS AND ECMWF LOOK TO BE BETTER SOLUTIONS FOR THE
PROGRESSION OF THIS SYSTEM.
ALTHOUGH SLIGHT CHANCE POPS LINGER INTO THE DAY THURSDAY...MOST OF
THE SHOWER ACTIVITY SHOULD BE E OF OUR AREA...ALTHOUGH THE 500MB
TROUGH WILL STILL BE OVERHEAD. EXPECT 8-10C 850MB TEMPS THURSDAY
INTO EARLY FRIDAY ON NW-W FLOW BEHIND THE EXITING COLD FRONT...WHICH
SHOULD KEEP SFC TEMPS AT OR SLIGHTLY BELOW NORMAL FOR THIS TIME OF
YEAR. THERE LOOKS TO BE SOME MINOR INDICATIONS IN A PATTERN CHANGE
ALOFT. THE 500MB RIDGE OVER THE MID ATLANTIC/OHIO VALLEY SHOULD
BECOME SUPPRESSED THURSDAY NIGHT...IN RESPONSE TO THE YET ANOTHER
500MB LOW PASSING OVER ONTARIO. THIS LAST ONE LOOKS TO GET HELD UP
OVER S HUDSON BAY/QUEBEC AS THE 500MB RIDGE PUSHES UP ACROSS THE
CENTRAL PLAINS STATES FOR FRIDAY THROUGH SUNDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 140 PM EDT SUN JUN 17 2012
TAF PERIOD WILL BEGIN WITH STRONG RIDGING IN PLACE THIS AFTERNOON.
IMPRESSIVE DRY AIR SOUNDINGS WILL ALSO ALLOW FOR W WINDS TO MIX DOWN
TO THE SURFACE...SO EXPECT GUSTY CONDITIONS AT ALL TAF SITES. AS THE
EVENING APPROACHES...A SHORTWAVE AND ASSOCIATED CONVECTION WILL
TRAVERSE THE AREA. SOME MODEL DISAGREEMENT ON WHERE BEST
INSTABILITY WILL SET UP ALONG WITH THE RESULTING PATH OF THE
SYSTEM...SO NOT CONFIDENT ENOUGH TO INCLUDE MENTION OF TSRA.
REGARDLESS...STRENGTHENING LOW-LEVEL JET/STRONG MOISTURE RETURN WILL
MOST LIKELY PRODUCE SHOWER ACTIVITY AND BORDERLINE MVFR CONDITIONS
DURING THE OVERNIGHT HOURS AT ALL TAF SITES. AS NIGHT TIME INVERSION
OVERSPREADS MUCH OF THE AREA...EXPECT LLWS TO BE OF CONCERN AT
KCMX/KSAW. TSRA/SHRA CHANCES WILL DIMINISH SOME DURING THE MORNING
HOURS...BEFORE THE NEXT ROUND OF CONVECTION DEVELOPS ACROSS UPPER MI
DURING THE AFTERNOON. CONTINUED WITH VCSH AT THIS TIME SINCE EXACT
LOCATION AND SET UP IS STILL UNKNOWN...BUT DO EXPECT SOME TSRA AND
POSSIBLE SEVERE WEATHER WITH THIS SYSTEM.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 521 AM EDT SUN JUN 17 2012
A BRIEF RIDGE OF HIGH PRESSURE TODAY...BEHIND THE EXITING SFC
LOW/TROUGH WILL MAKE WAY FOR THE NEXT LOW DEVELOPING OVER S CANADA
AND THE NORTHERN PLAINS STATES. EXPECT THE NORTHERN LOW TO PUSH
ACROSS ONTARIO MONDAY /WITH GUSTS NEARING 30-35KTS CENTRAL AND
E/...WITH A TROUGH EXTENDING THROUGH LS AND INTO NE. GIVEN THE
ADDITIONAL MOISTURE ACROSS THE AREA WITH THE TROUGH NEARBY FOR MUCH
OF THE PERIOD...FOG WILL BE A COMMON THEME. A SECONDARY LOW
OVER NE WILL RIDE UP THE TROUGH AND CROSS LS AND PUSH INTO ONTARIO
WEDNESDAY AFTERNOON/EVENING...WHICH WILL FINALLY PUSH THE TROUGH SE
OF THE AREA. HIGH PRESSURE WILL THEN SLOWLY BUILD IN AND LINGER
THURSDAY THROUGH THE START OF THE UPCOMING WEEKEND. WSW GUSTS MAY
INCREASE AGAIN TO NEAR 25-30KTS THURSDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KF
AVIATION...JMW
MARINE...KF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
349 PM CDT SUN JUN 17 2012
.DISCUSSION...
TO SAY THE NEXT FEW DAYS WILL BE ACTIVE IS AN UNDERSTATEMENT WITH
SEVERAL ROUNDS OF THUNDERSTORMS/SEVERE WEATHER EXPECTED...ALONG WITH
A RISK FOR MORE FLASH FLOODING. STILL ANTICIPATING A SEVERE WEATHER
EPISODE THIS AFTERNOON INTO TONIGHT. LOOKING LIKE WE GET A BREAK IN
THE ACTION DURING THE DAY MONDAY...BEFORE A WARM FRONT COMES SURGING
BACK NORTH MONDAY NIGHT. THIS FRONT WILL BE ANCHORED OVER THE AREA
TUESDAY THOUGH WEDNESDAY...WITH MULTIPLE ROUNDS OF THUNDERSTORMS
EXPECTED OVER THOSE TWO DAYS. BESIDE SEVERE WEATHER
TUESDAY/WEDNESDAY...FLOW WILL BE NEARLY PARALLEL TO THE FRONT...WITH
THREAT FOR TRAINING THUNDERSTORMS AND FLASH FLOODING EXISTING THOSE
DAYS.
WATER VAPOR IMAGERY ALONG WITH RAP ANALYSIS SHOWS A VERY STRONG
UPPER JET /100-150 KTS/ SLAMMING ACROSS THE NORTHERN ROCKIES AND
INTO THE NORTHERN PLAINS RIGHT NOW. BATCH OF SHOWERS CONTINUES TO
WORK EAST ACROSS MN INTO WI THIS AFTERNOON ON NOSE OF 40 KT LLJ
AND LEADING BLAST OF THETA-E ADVECTION. BACK FURTHER
WEST...STARTING TO SEE A NICE WARM FRONT TAKE SHAPE BEHIND THE
CLOUDS IN SW MN INTO NE SD...ALMOST RIGHT ALONG THE BUFFALO RIDGE.
MLCAPES SOUTH OF THE BOUNDARY IN ERN SODAK HAVE INCREASED TO
AROUND 3000 J/KG. INCREASING WINDS ALOFT AND BACKING WINDS NORTH
OF THE BOUNDARY HAVE RESULTED IN BOTH DEEP LAYER SHEAR /NOW AROUND
50 KTS/ AND 0-1KM SHEAR /25-30 KTS ALONG THE WARM FRONT/
INCREASING QUITE A BIT THIS AFTERNOON. HI-RES GUIDANCE ALL
SIMILAR WITH INITIATING CONVECTION BY 22Z ALONG THE SD/MN BORDER
AROUND YELLOW MEDICINE/LAC QUI PARLE COUNTIES. GIVEN SHEAR AND
INSTABILITY PROFILES...STORM TYPE WILL BE SUPER CELLULAR WITH A
GOOD RISK OF VERY LARGE HAIL...DAMAGING WINDS...AND TORNADOES
THROUGH ABOUT 0/1Z. WHAT IS MORE WORRISOME IS WHAT HAPPENS AFTER
THESE STORMS INITIATE. IT DOES NOT MATTER WHAT HI-RES GUIDANCE YOU
LOOK AT...HRRR/NMM/ARW/MPX-WRF...THEY ALL CONGEAL THE STORMS OVER
CENTRAL MINNESOTA INTO A LINE AND SEND IT RACING EAST ACROSS THE
AREA TONIGHT. BIG WORRY HERE IS THAT PARAMETERS APPEAR TO BE
COMING TOGETHER FOR THE FORMATION OF A SIGNIFICANT DERECHO THIS
EVENING THAT THEN ROUGHLY FOLLOWS I-94 DOWN INTO THE TWIN CITES.
BY 6Z...THE RAP HAS MUCAPE OVER THE TWIN CITIES OF AROUND 2500
J/KG...DCAPE OF AROUND 1000 J/KG...AND MOST WORRISOME OF ALL...AN
H85 LLJ INCREASING TO BETWEEN 65 AND 70 KTS ALL POINT TO THE
POTENTIAL FOR A SIGNIFICANT DERECHO. THE BIG HOPE IS THAT
SIGNIFICANTLY RAIN COOLED AIR /TEMPS IN RAIN HAVE FALLEN INTO THE
LOW AND MID 60S/ WILL STABILIZE THE BOUNDARY LAYER ENOUGH ACROSS
ERN MN THAT BOUNDARY LAYER CAN NOT RECOVER ENOUGH TO ALLOW WINDS
TO REACH THE SFC AND WE END UP WITH AN ELEVATED MCS. EITHER WAY
YOU SLICE IT...LOOKS LIKE IT WILL BE A LONG NIGHT FOR THE MPX
AREA.
TONIGHT...MODELS DRIVE A FRONT EAST OF THE AREA...WITH MONDAY NOW
LOOKING DRY DURING THE DAY AND CUT POPS OUT OF ALL BUT THE FAR SE
CWA. LATE MONDAY NIGHT...THE WARM FRONT COMES SURGING BACK
NORTH...WITH MODELS SHOWING ANOTHER ROUND OF THUNDERSTORMS COMING
INTO WRN AND CENTRAL MN MAINLY AFTER 06Z TUESDAY ON YET ANOTHER 50 KT
LLJ. THIS THEN LEADS US INTO WHAT IS LOOKING LIKE THE MOST ACTIVE
WEATHER PERIOD IN THE COMING DAYS FOR TUESDAY THROUGH WEDNESDAY.
GOOD NEWS HERE IS MODELS ARE NOW SHOWING BETTER AGREEMENT WITH
EACH OTHER THESE TWO DAYS...WITH THE ECMWF NOW BEING LESS
PROGRESSIVE AND SHOWING FRONTAL PLACEMENT MUCH MORE SIMILAR TO
WHAT THE GFS HAS BEEN SHOWING THE PAST COUPLE OF DAYS. WILL BE
VERY WARM AND HUMID SOUTH OF THE BOUNDARY...WITH A VERY UNSTABLE
AIRMASS LIKELY IN PLACE BOTH DAYS. DURING THE DAY TUESDAY...MAY NOT
SEE MUCH ACTIVITY AS STRONG CAPPING INVERSION...WITH H7 TEMPS
INCREASING TO AROUND +14C...BUT TUESDAY NIGHT...MODELS SHOW MID
LEVEL TEMPS COOLING...WITH ALL SORTS OF CONVECTION TAKING OFF.
WORRY BOTH TUESDAY AND WEDNESDAY IS THAT BESIDE ALL THE
INSTABILITY...AN IMPRESSIVE 70-90 KT SW MID-LEVEL JET WILL BE
SPLAYED OUT ACROSS CENTRAL MN...WITH PLENTY OF SHEAR PRESENT FOR
ORGANIZED/SEVERE CONVECTION. IN ADDITION...UPPER FLOW WILL BE NEARLY
PARALLEL TO THE FRONT TUES/WED...WHICH MEANS POTENTIAL FOR
TRAINING STORMS WILL BE HIGH...AND WITH PWATS UP AROUND 2 INCHES
/180 PERCENT OF NORMAL/...FLASH FLOODING WILL AGAIN BE A CONCERN.
MODELS FINALLY SHOWING WNW FLOW DEVELOPING ALOFT BY
THURSDAY...WITH THE MOISTURE AND ASSOCIATED RAIN FINALLY GETTING
KICKED OUT OF HERE. FOLLOWED THE ECMWF FOR THU/FRI...WHICH IS
DRY...BUT THE GFS DOES SHOW ANOTHER WAVE MOVING ACROSS THE AREA
THU NIGHT/FRI...JUST AS THE ECWMF SLIDES A 1020 MB HIGH ACROSS THE
AREA. BETTER AGREEMENT FOR THUNDERSTORMS SHOWS UP SATURDAY WHEN
THE ECWMF/GFS SHOW A STRONG WARM FRONT MOVING UP INTO THE MPX AREA
AS A SFC LOW WORKS ACROSS SODAK INTO IA. AS A RESULT...BROUGHT
CHANCE POPS BACK FRIDAY NIGHT THOUGH SAT NIGHT. LOOKING JUST
BEYOND THE FORECAST...THE GFS/ECMWF SHOW AN UPPER RIDGE BUILDING
IN ACROSS THE CENTRAL CONUS FOR THE LAST WEEK OF JUNE...WITH
SIGNS OF A DECENT HEAT WAVE SHOWING UP FOR THE END OF JUNE.
&&
.AVIATION... /18Z TAF ISSUANCE/
AS YOU CAN SEE..THUNDERSTORMS HAD RAPIDLY DEVELOPED OVER WESTERN AND
SOUTHERN MINNESOTA...THESE SHRA/TSRA WILL CONTINUE TO MOVE INTO
EAST CENTRAL MN AND WESTERN WISCONSIN DURING THE AFTERNOON. WARM
FRONT CONTINUED TO SURGE NORTHWARD INTO SOUTHWEST MN. SFC LOW WILL
TRACK EAST OVER INTO WEST CENTRAL MN. STRONG TO SEVERE THUNDERSTORMS
ARE LIKELY TO DEVELOP AHEAD OF THE FRONTAL BOUNDARY AND SFC
LOW....THEN CONGEAL INTO LARGE BOW SEGMENT LATER TONIGHT OVER
CENTRAL MN AND NORTHWEST WISCONSIN. WEATHER CONDITIONS WILL LOWER TO
IFR CONDITIONS IN HEAVY RAIN AND THUNDERSTORMS WITH VFR CONDITIONS
PREVAILING OUTSIDE OF THE THUNDERSTORM ACTIVITY DURING THE REMAINDER
OF THE AFTERNOON AND EVENING. CEILING HEIGHTS LOWERING BETWEEN
3000-4000 FEET AGL OVERNIGHT.
.KMSP...SCATTERED THUNDERSTORMS MAINLY EARLY THIS AFTERNOON OR
THROUGH 300 PM. ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS IS
EXPECTED LATER THIS EVENING/OVERNIGHT. SFC WINDS WILL REMAIN
SOUTHERLY 10 TO 15 MPH WITH HIGHER GUST NEAR THE VICINITY OF
THUNDERSTORMS.
OUTLOOK...
MONDAY...VFR/MVFR WITH CHC OF TSRA. WINDS SW 10KT SHIFTING NW.
TUESDAY...VFR/MVFR WITH TSRA POSSIBLE. SE TO S WINDS 20 TO 25 KTS.
WEDNESDAY...VFR/MVFR WITH TSRA POSSIBLE. WINDS NW AT 12 TO 17 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
MPG/JVM
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1258 PM CDT SUN JUN 17 2012
.UPDATE...
.MESOSCALE DISCUSSION...
THUNDERSTORMS ARE RAPIDLY MOVING INTO SW MN THIS MORNING ON NOSE
OF RAP ANALYZED 40+ KT LLJ AND WITHIN ZONE OF STRONG H85 WAA.
LATEST SPC MESOANALYSIS SHOWS 2000+ J/KG OF MUCAPE FEEDING UP INTO
THIS AREA OF WAA...WITH THE EXPANSION OF THUNDERSTORMS OVER
SOUTHWEST MINNESOTA RESULTING. 0-6KM DEEP LAYER SHEAR IS AROUND 40
KTS RIGHT NOW...SO A MARGINAL RISK FOR HAIL WILL EXIST WITH THIS
PRIMARILY ELEVATED CONVECTION FROM THE MORNING INTO THE EARLY
AFTERNOON. THESE STORMS WILL BE WORKING OVER TO THE I-35 CORRIDOR
SHORTLY AFTER 18Z...WITH THE THREAT FOR HAIL CONTINUING. IF THESE
STORMS CAN BECOME ROOTED IN THE BOUNDARY LAYER LATER THIS
AFTERNOON...THEN A RISK FOR DAMAGING STRAIGHT LINE WINDS WILL
EXIST AS WELL.
FOR THE SEVERE RISK LATER THIS AFTERNOON /WHICH IS WHAT PROMPTED
THE MODERATE RISK FROM THE SPC/...THE BIG QUESTION REMAINS HOW FAR
NORTH DOES A VERY WARM EML AND ATTENDANT STRONG CAPPING INVERSION
MAKE IT. TREND FROM THE LAST FEW RUNS OF THE RAP/HRRR SHOW THAT
THE SEVERE THREAT FOR LATER THIS AFTERNOON LIKELY HAS SHIFT NORTH
SOME FROM WHAT GUIDANCE LAST NIGHT WAS SHOWING. THIS NORTHWARD
SHIFT IS ALSO SUPPORTED BY THE LATEST 12Z NAM. BASED ON A RAP/NAM
COMBO...WARM FRONT LOOKS TO COME INTO WRN MN SOMEWHERE BETWEEN
WHEATON AND MARSHALL...WITH CONVECTION INITIATING BETWEEN 3 AND 5
PM IN NE SODAK/WEST CENTRAL MINNESOTA. BELIEVE THE HRRR
REFLECTIVITY FORECAST IS A BIT NORTH WITH THINGS BASED ON WHERE
THE RAP PLACES SFC FEATURES...BUT SUSPECT THE STRONG CAP MAKES IT
DIFFICULT TO SEE MUCH OF ANYTHING THIS AFTERNOON/EVENING SOUTH OF
YELLOW MEDICINE COUNTY. GIVEN 2000-3000 J/KG OF MIXED LAYER
CAPE..ALONG WITH 0-6 KM SHEAR INCREASING TO AROUND 60 KTS...AND
0-1KM SHEAR PEGGED BY THE RAP TO BE BETWEEN 30 AND 40
KTS...WHATEVER DOES GET GOING IN WEST CENTRAL MN WILL HAVE A HIGH
LIKELIHOOD OF BEING SUPERCELLULAR WITH THE ATTENDANT RISK FOR VERY
LARGE HAIL...STRONG WINDS...AND TORNADOES EXISTING. STILL LOOKING
LIKE THIS ACTIVITY WILL CONGEAL INTO A LINEAR SYSTEM THIS EVENING
AND TRACK EAST ACROSS THE REST OF MINNESOTA INTO WI TONIGHT. WITH
THE NRN SHIFT IN MODELS...SUSPECT GREATEST THREAT OF SEVERE
WEATHER THROUGH TONIGHT WILL BE ALONG AND NORTH OF THE I-94 WITH
WHAT IS EXPECTED TO BE AN MCS. SOUTHERN MN MAY END UP NOT SEEING
MUCH AFTER THIS MORNING DUE TO INCREASING CAP STRENGTH.
&&
.PREV DISCUSSION...
/ISSUED 605 AM CDT SUN JUN 17 2012/
ACTIVE WEATHER REMAINS ON TRACK TO CONTINUE ACROSS THE REGION FOR
THE NEXT SEVERAL DAYS. STRONG TO SEVERE THUNDERSTORMS WILL DEVELOP
TOMORROW AFTERNOON OUT WEST AND MOVE EASTWARD ACROSS THE CWA
OVERNIGHT. A FRONTAL BOUNDARY WILL STALL ACROSS THE REGION...AND
THIS WILL BE THE FOCUS FOR REPEATED ROUNDS OF SHOWERS AND
THUNDERSTORMS. FLOODING ALSO REMAINS A CONCERN WITH TRAINING
THUNDERSTORMS POSSIBLE DURING THIS TIME PERIOD. THINGS WILL TRY TO
QUIET DOWN TOWARD THE END OF NEXT WEEK.
TODAY THROUGH WEDNESDAY....EARLY MORNING WATER VAPOR IMAGERY
OVERLAID WITH 500MB HEIGHTS AND H250 WINDS SHOWS A TREMENDOUS +150KT
PACIFIC JET CRASHING ONSHORE OVER THE PUGET SOUND AND RACING TOWARD
THE IDAHO PANHANDLE. THIS WILL BE THE MAIN PLAYER IN THE NEAR-TERM
WEATHER ACROSS THE UPPER MIDWEST. CLOSER TO HOME AT THE SURFACE...A
COLD FRONT HAD PUSHED THROUGH THE CWA WITH A RIDGE OF HIGH PRESSURE
CENTERED OVER THE MISSOURI RIVER VALLEY. A LEE SIDE SURFACE LOW WAS
BEGINNING TO DEVELOP ACROSS THE HIGH PLAINS OF MONTANA IN RESPONSE
TO THE APPROACHING JET...AND THIS WILL CONTINUE TO DEEPEN OVER THE
NEXT 18 HOURS AND INDUCE SOUTHERLY FLOW ACROSS THE CENTRAL PLAINS.
THE COLD FRONT WHICH JUST MOVED THROUGH WILL SURGE NORTHWARD AS A
WARM FRONT AND BE DRAPED ACROSS EASTERN SOUTH DAKOTA THROUGH
SOUTHWEST MINNESOTA. A CONDITIONAL SEVERE THREAT EXISTS IN THE
VICINITY OF THIS BOUNDARY. THE ATMOSPHERE WILL BECOME VERY
UNSTABLE...WITH SBCAPES OF 2000 TO 3000J/KG IN THE WARM SECTOR BY
MID AFTERNOON. FORECAST SOUNDINGS SHOW STRONG VEERING WINDS IN THE
LOWER LEVELS...WITH 0-3 HELICITY VALUES OF INCREASING FROM ABOUT 150
M2/S2 TO OVER 500 M2/S2 ALONG THE WARM FRONG AS THE BOUNDARY LAYER
DECOUPLES. CONVECTION SHOULD DEVELOP LATE THIS AFTERNOON ACROSS THE
EASTERN DAKOTAS...WITH A FEW TORNADOES POSSIBLE SHORTLY AFTER
INITIATION...ESPECIALLY WITH RIGHT MOVING STORMS THAT ARE ABLE TO
GENERATE THEIR OWN SRH. EXPECT THESE STORMS TO GROW UPSCALE...AND
COULD SEE A TRANSITION TO A DERECHO THAT PROPAGATES ESE ALONG THE
AFOREMENTIONED WARM FRONT. IF THIS SCENARIO PLAYS OUT...EXPECT AN
OUTFLOW BOUNDARY TO REINFORCE THE FRONT ON MONDAY...WHICH WILL MOVE
NORTHWARD AGAIN MONDAY NIGHT AS ANOTHER SURFACE LOW DEVELOPS TO THE
SOUTHWEST. WITH STEERING LAYER WINDS PARALLEL TO THE
BOUNDARY...COULD SEE TRAINING THUNDERSTORMS AND A FLASH FLOOD THREAT
FOR MONDAY NIGHT INTO TUESDAY...IN ADDITION TO ANOTHER ROUND OF
SEVERE WEATHER AS A SHORTWAVE TRAVERSES THE REGION. AS FAR AS TEMPS
GO...SOUTH OF THE BOUNDARY H850 TEMPS WILL EXCEED 20C...SO WILL END
UP BEING A HOT AND HUMID DAY NEAR THE IA/MN BORDER WITH A 20F NORTH
TO SOUTH TEMPERATURE GRADIENT ACROSS THE STATE. SO IN
SUMMATION...SPC HAS UPGRADED WESTERN PORTIONS OF THE CWA TO A
MODERATE RISK FOR THE REASONS LISTED ABOVE....AND A SECOND
SEVERE/HEAVY THREAT WILL BE LATE MONDAY EVENING INTO TUESDAY ACROSS
MAINLY THE EASTERN HALF OF THE CWA AS THE WARM FRONT LIFTS
NORTHWARD. FINALLY...THE SOUTHERN PART OF THE CWA WILL BE LOCATED IN
THE WARM SECTOR ON TUESDAY...AND WILL LIKELY SEE A THIRD ROUND OF
STORMS TUESDAY NIGHT INTO WEDNESDAY MORNING ALONG THE TRAILING COLD
FRONT AS THE PARENT WAVE MOVES ACROSS THE REGION TOWARDS HUDSON BAY.
THURSDAY THROUGH SATURDAY...ONCE THIS ACTIVE PERIOD IS IN THE REAR
VIEW MIRROR...WILL TRANSITION TO NORTHWEST FLOW FOR THE END OF THE
WEEK. BOTH THE ECMWF AND GFS HAVE BEEN CONSISTENT WITH MODERATE
HEIGHT RISES AND WEAK HIGH PRESSURE BUILDING ACROSS THE REGION.
THEREFORE WENT OPTIMISTICALLY DRY FOR THURSDAY AND FRIDAY. ON FRIDAY
NIGHT MODELS TRY TO BRING A SHORTWAVE ACROSS THE HIGH PLAINS...WITH
THETA_E ADVECTION SPREADING ACROSS THE UPPER MIDWEST AHEAD OF IT.
THEREFORE HAVE CONTINUED PRECIP CHANCES FOR THE EARLY PART OF THE
UPCOMING WEEKEND. TEMPERATURES WILL COOL OFF CLOSER TO THE SEASONAL
AVERAGE FOR MID TO LATE JUNE.
&&
.AVIATION... /18Z TAF ISSUANCE/
AS YOU CAN SEE..THUNDERSTORMS HAD RAPIDLY DEVELOPED OVER WESTERN AND
SOUTHERN MINNESOTA...THESE SHRA/TSRA WILL CONTINUE TO MOVE INTO
EAST CENTRAL MN AND WESTERN WISCONSIN DURING THE AFTERNOON. WARM
FRONT CONTINUED TO SURGE NORTHWARD INTO SOUTHWEST MN. SFC LOW WILL
TRACK EAST OVER INTO WEST CENTRAL MN. STRONG TO SEVERE THUNDERSTORMS
ARE LIKELY TO DEVELOP AHEAD OF THE FRONTAL BOUNDARY AND SFC
LOW....THEN CONGEAL INTO LARGE BOW SEGMENT LATER TONIGHT OVER
CENTRAL MN AND NORTHWEST WISCONSIN. WEATHER CONDITIONS WILL LOWER TO
IFR CONDITIONS IN HEAVY RAIN AND THUNDERSTORMS WITH VFR CONDITIONS
PREVAILING OUTSIDE OF THE THUNDERSTORM ACTIVITY DURING THE REMAINDER
OF THE AFTERNOON AND EVENING. CEILING HEIGHTS LOWERING BETWEEN
3000-4000 FEET AGL OVERNIGHT.
.KMSP...SCATTERED THUNDERSTORMS MAINLY EARLY THIS AFTERNOON OR
THROUGH 300 PM. ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS IS
EXPECTED LATER THIS EVENING/OVERNIGHT. SFC WINDS WILL REMAIN
SOUTHERLY 10 TO 15 MPH WITH HIGHER GUST NEAR THE VICINITY OF
THUNDERSTORMS.
OUTLOOK...
MONDAY...VFR/MVFR WITH CHC OF TSRA. WINDS SW 10KT SHIFTING NW.
TUESDAY...VFR/MVFR WITH TSRA POSSIBLE. SE TO S WINDS 20 TO 25 KTS.
WEDNESDAY...VFR/MVFR WITH TSRA POSSIBLE. WINDS NW AT 12 TO 17 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
MPG/JRB/JM
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
323 PM CDT SUN JUN 17 2012
.SHORT TERM...
ISSUED AT 321 PM CDT SUN JUN 17 2012
(THIS EVENING AND TONIGHT)
THERE IS A CHANCE FOR SHOWER AND THUNDERSTORM ACTIVITY ACROSS
CENTRAL AND NORTHERN PORTIONS OF THE CWA WHERE AMPLE DAYTIME HEATING
AND CU FIELD DEVELOPMENT HAS OCCURRED INVOF A WEAKLY DEFINED
SYNOPTIC SCALE FRONT THAT HAS BECOME NEARLY STATIONARY ACROSS THE
NORTHERN TIER OF THE CWA OVER THE PAST SEVERAL HOURS.
GFS...NAM...AND HRRR MODELS ARE ALL CONSISTENT WITH INITIATING
CONVECTION GENERALLY ALONG THE I-70 CORRIDOR THIS EVENING...THOUGH
CURRENT THINKING IS THAT STORMS THAT DEVELOP SHOULD WEAKEN AFTER
SUNSET WITH THE LOSS OF DIURNAL HEATING. HAVE CONTINUED CHC POPS
ACROSS THE CWA THIS EVENING...ALONG WITH THE TREND OF GRADUAL
NORTHEASTWARD PROGRESSION AS THE FRONT RETREATS NORTHWARD.
THE RIDGE THAT WAS TEMPORARILY SHUNTED BY THE DEEPENING SHORTWAVE
RESPONSIBLE FOR CONVECTIVE ACTIVITY OVER THE PAST 24 HOURS WILL
BEGIN TO REASSERT ITSELF OVERNIGHT TONIGHT...AND COMBINED WITH THE
NORTHEASTWARD PROGRESSION OF THE SHORTWAVE WILL RESULT IN A
TIGHTENED TEMPERATURE GRADIENT ACROSS THE REGION. THEREFORE...WINDS
WILL NOT DIE DOWN VERY MUCH DURING THE OVERNIGHT HOURS...AND WE
COULD EVEN SEE SOME GUSTY SOUTH WINDS BEGINNING MONDAY MORNING BEFORE
DAYBREAK.
JP
&&
.LONG TERM...
ISSUED AT 321 PM CDT SUN JUN 17 2012
(MONDAY THROUGH SUNDAY)
UPPER RIDGE WILL BEGIN BUILDING BACK INTO THE LOWER AND MID
MISSISSIPPI VALLEY ON MONDAY. STRONG CAP EVIDENT IN SOUNDINGS WITH
DEEP MIXING TO BETWEEN 850-800MB. EXPECTING STRONG WINDS AS
PRESSURE GRADIENT TIGHTENS BETWEEN A DEVELOPING LOW OVER EASTERN
COLORADO AND THE HIGH OFF THE EAST COAST. SUSTAINED WINDS OF
15-20KTS WITH GUSTS TO 30KTS ARE LIKELY...BUT IT LOOKS LIKE WE`LL
STAY BELOW WIND ADVISORY CRITERIA. WITH THE DEEP MIXING AND STRONG
SOUTHWEST FLOW WE SHOULD EASILY HIT THE MID 90S ACROSS MOST OF THE
AREA. TUESDAY`S WEATHER WILL BE NEARLY A CARBON COPY OF
MONDAY...THOUGH IT MAY BE A BIT LESS WINDY ACROSS MOST OF THE AREA
AS THE TIGHTER GRADIENT MOVES OUT ACROSS NORTHWEST MISSOURI AND THE
EASTERN PLAINS. BY WEDNESDAY A STRONG SHORTWAVE WILL RIPPLE ACROSS
THE NORTHERN U.S. FLATTENING THE UPPER RIDGE. THIS WILL ALLOW A
COLD FRONT TO DROP DOWN ACROSS THE MIDWEST. ECMWF AND GFS DIVERGE
AT THIS JUNCTURE WITH THE GFS STALLING AND WASHING THE FRONT OUT ON
THE MO/IA BORDER THURSDAY WHILE THE ECMWF IS MORE AGGRESSIVE TAKING
THE COLD FRONT ALL THE WAY THROUGH THE CWFA INTO SOUTHERN MISSOURI
OR NORTHERN IOWA. BOTH MODELS KICK OUT SOME PRECIP IN THE VICINITY
OF THE FRONT...BUT WITHOUT GOOD AGREEMENT IN THE MODELS FELL
UNCERTAINTY IS TOO GREAT TO BE TOO SPECIFIC WITH POPS AT THIS TIME.
CARNEY
&&
.AVIATION...
ISSUED AT 1218 PM CDT SUN JUN 17 2012
PRIMARY CONCERN THIS FORECAST PERIOD IS THE ONSET AND SUBSEQUENT
DEGREE OF COVERAGE OF SHOWER AND THUNDERSTORM ACTIVITY THIS
AFTERNOON AND EVENING. CURRENTLY...AN AREA OF SCT-BKN CU AOA 3KFT
EXTENDS FROM THE KMCI THROUGH KCOU AND TO KSTL. WHILE THIS CU
FIELD IS SOUTH OF THE SYNOPTIC FRONT...WHICH IS CURRENTLY
EXTENDING THROUGH CENTRAL IL AND NORTHERN MO...VERY CLOSE TO
KUIN...AND NORTH OF LINGERING OUTFLOW FROM LAST NIGHTS
ACTIVITY...CURRENTLY ACROSS SOUTHERN MO AND SOUTHERN IL...EXPECT
INITIAL SHOWER AND THUNDERSTORM ACTIVITY TO DEVELOP WITHIN THIS
FIELD DURING THE AFTERNOON HOURS. THUS...HAVE INCLUDED A VCTS
MENTION FOR KCOU FOR SEVERAL HOURS LATER THIS AFTERNOON AND EARLY
THIS EVENING...THOUGH THE QUESTION REMAINS REGARDING HOW MUCH
AREAL COVERAGE WILL BE SEEN WITH STORMS AS THEY DEVELOP. THIS
UNCERTAINTY HAS WARRANTED KEEPING METRO AREA TAF SITES AND KUIN
DRY ATTM...THOUGH UPDATES WILL LIKELY BE WARRANTED THIS AFTERNOON
AS DAYTIME HEATING SERVES TO FURTHER DESTABILIZE THE ATMOSPHERE.
OTHERWISE...CONDITIONS HAVE BEEN TEETERING ON THE MVFR/VFR
THRESHOLD THROUGH THE MORNING HOURS...THOUGH VFR CONDITIONS ARE
EXPECTED TO PREVAIL THIS AFTERNOON. WINDS WILL GRADUALLY BACK TO
THE SOUTH AS A WEAK FRONT LIFTS NORTHWARD THIS AFTERNOON...AND
WIND SPEEDS ARE EXPECTED TO INCREASE DRAMATICALLY BY MONDAY
MORNING AS A PRESSURE GRADIENT STRENGTHENS ACROSS THE REGION.
SOUTHERLY WINDS LATE MONDAY MORNING AND MONDAY AFTERNOON WILL GUST
TO AROUND 25KT ACROSS THE REGION.
SPECIFICS FOR KSTL...
CU FIELD IS ATTEMPTING TO TAKE HOLD OVER KSTL CURRENTLY...THOUGH
AN IMPROVEMENT TO VFR CONDITIONS IS EXPECTED THIS AFTERNOON. THERE
IS SOME UNCERTAINTY REGARDING SHOWER AND THUNDERSTORM DEVELOPMENT
THIS AFTERNOON WITHIN THE CU FIELD...ESPECIALLY AS A WEAK FRONT TO
THE SOUTH SLOWLY DRIFTS NORTHWARD THROUGH THE DAY TODAY. GIVEN
AREAL COVERAGE IS NOT EXPECTED TO BE GREAT...HAVE ELECTED TO KEEP
KSTL DRY FOR NOW AND WILL MONITOR CONDITIONS AS THEY EVOLVE. ANY
ACTIVITY THAT DEVELOPS...HOWEVER...SHOULD WEAKEN AND DIMINISH
AFTER SUNSET WITH THE LOSS OF DIURNAL HEATING. CURRENT WESTERLY
WINDS WILL BACK TO THE SW AND EVENTUALLY THE SOUTH AS THE FRONT
MOVES NORTH...AND WILL BECOME GUSTY BY MONDAY MORNING DUE TO A
TIGHTENING PRESSURE GRADIENT ACROSS THE REGION.
JP
&&
.PRELIMINARY POINT TEMPS/POPS...
ST LOUIS 74 94 74 95 / 30 5 0 5
QUINCY 72 93 72 93 / 30 5 5 10
COLUMBIA 72 93 71 92 / 20 5 0 10
JEFFERSON CITY 72 94 72 93 / 10 5 0 10
SALEM 71 92 73 93 / 20 5 0 0
FARMINGTON 69 91 69 92 / 10 0 0 5
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS HASTINGS NE
400 PM CDT SUN JUN 17 2012
.SHORT TERM...THROUGH MONDAY AFTERNOON. PRIMARY CONCERN IS HOW
CLOSE PARTS OF THE SOUTHERN CWA WILL COME TO MEETING HEAT ADVISORY
CRITERIA ON MONDAY AFTERNOON...WITH NO SHOWERS/THUNDERSTORMS
FORECAST THROUGH THE NEXT 24 HOURS.
19Z OBJECTIVE SURFACE ANALYSIS REVEALED A STILL-DEEPENING 996MB LOW
OVER CENTRAL SD...IN RESPONSE TO A 110KT 300MB JET STREAK TRACKING
DUE EAST OUT OF MT INTO THE WESTERN DAKOTAS. A TROUGH AXIS
EXTENDED SOUTHWEST FROM THIS LOW INTO NORTHWEST NEB...BUT STILL
WELL NORTHWEST OF THE CWA. IN RESPONSE TO THE PRESSURE
FALLS...AND WITH MIXING TO AROUND THE 750MB ACROSS MOST OF THE CWA
PER FORECAST SOUNDINGS...A BREEZY/WINDY DAY HAS ENSUED...WITH
SUSTAINED SOUTHERLY SPEEDS BETWEEN 20-25 MPH/GUSTS TO AROUND 30
MPH AND LOCALLY HIGHER. AS SUSPECTED IN THE EARLIER AFTERNOON
DISCUSSION...DEWPOINTS HAVE STARTED TO DROP SEVERAL DEGREES ACROSS
THE CWA FROM WEST TO EAST THIS AFTERNOON IN RESPONSE TO THE DEEP
MIXING. IN FACT...WITH DEWPOINTS ALL THE WAY DOWN INTO THE UPPER
40S/LOW 50S IN SOME SOUTHWEST COUNTIES...RED FLAG WARNING CRITERIA
OF 20 PERCENT IS BEING BREACHED IN A FEW SPOTS...BUT WITH ONLY KS
COUNTIES OFFICIALLY HAVING A FAVORABLE FUEL STATUS FOR LARGE FIRE
GROWTH...AND ANY RELATIVE HUMIDITY VALUES BELOW 20 PERCENT LIKELY
TO ONLY AFFECT A SMALL AREA FOR 3 HOURS OR MORE...WILL NOT BE
ISSUING ANY FIRE HEADLINES. TEMP WISE...ALTHOUGH PARTS OF MAINLY
THE NORTHEAST HALF OF THE CWA COULD FALL SHORT OF FORECAST HIGHS
BY A FEW DEGREES...STILL SHOULD END UP WITH SOLID COVERAGE OF AT
LEAST LOW-MID 90S ACROSS MOST NEB COUNTIES...AND UPPER 90S IN MOST
OF KS ALONG WITH FURNAS COUNTY AREA. ALOFT...THE AFOREMENTIONED
JET STREAK AND ASSOCIATED MID LEVEL SHORTWAVE TRANSLATING ACROSS
THE NORTHERN PLAINS/SOUTHERN CANADA REGION IS BY FAR THE MAIN
FEATURE OF INTEREST...WITH WEAKER QUASI-ZONAL FLOW OVER THE LOCAL
AREA.
FOR TONIGHT...KEPT ALL THUNDERSTORM MENTION OUT OF THE
FORECAST...DESPITE THE PRESENCE OF THE SURFACE TROUGH SLOWLY
MIGRATING TOWARD THE NORTHWEST CWA. WITH 700MB TEMPS INCREASING
INTO THE 12-15C RANGE AS A PRONOUNCED ELEVATED MIXED LAYER MOVES
IN FROM THE WEST...THIS SHOULD KEEP A STOUT CAP IN PLACE. A FEW
MODELS SUCH AS THE RAP AND 18Z NAM ATTEMPT TO BREAK OUT A FEW HIGH
BASED STORMS ACROSS NORTH CENTRAL/NORTHEAST NEB AT SOME POINT LATE
THIS AFTERNOON/THIS EVENING...BUT ANY OF THIS ACTIVITY SHOULD HOLD
OFF TO OUR NORTH. OTHERWISE...AS THE PRIMARY SURFACE LOW PRESSURE
SYSTEM MIGRATES EAST TOWARD THE IA/MN/NE/SD BORDER AREA
OVERNIGHT...A STEADY SOUTH BREEZE WILL PERSIST ACROSS MOST OF THE
CWA ALL NIGHT LONG...WITH BREEZES OF AT LEAST 20-25 MPH REMAINING
IN PLACE. LATE IN THE NIGHT HOWEVER...SPEEDS WILL START TO SLACKEN
ACROSS NORTHWEST COUNTIES AS THE SURFACE TROUGH FINALLY MOVES IN.
MADE LITTLE CHANGE TO LOW TEMPERATURES...STILL AIMING FOR MID 60S
FAR NORTHWEST TO LOW 70S EAST/SOUTHEAST...AND WOULD NOT BE
SURPRISED TO SEE MORE CENTRAL AREAS HOLD ABOVE THE 70-MARK AS
WELL.
TURNING TO THE 12Z-00Z DAYTIME HOURS MONDAY...A DRY FORECAST
CONTINUES AS A STOUT CAP WITH 700MB TEMPS ON THE ORDER OF 13-16C
REMAINS FIRMLY IN PLACE. ALOFT...THE FLOW REMAINS QUASI-ZONAL OVER
THE CENTRAL CONUS...AS ONE SHORTWAVE DEPARTS ACROSS THE NORTHERN MN
REGION...WHILE THE NEXT WAVE OF INTEREST TRANSITIONS EASTWARD
INTO THE NORTHERN ROCKIES. AT THE SURFACE...WIND TRENDS ARE A BIT
TRICKY THROUGH THE DAY...AS THE SURFACE TROUGH/WEAK COLD FRONT
SINKS AT LEAST PARTWAY INTO THE CWA DURING THE FIRST PART OF THE
DAY USHERING IN A LIGHT WESTERLY/NORTHERLY COMPONENT...BUT THEN
THE BOUNDARY RETREATS BACK NORTHWARD IN RESPONSE TO HIGH PLAINS
PRESSURE FALLS...WITH ALL AREAS BACK IN A LIGHT TO STEADY
SOUTHEAST BREEZE BY LATE AFTERNOON. HOWEVER...GIVEN THE WARM START
AND VERY WARM 850MB TEMPS IN PLACE...A RATHER HOT DAY IS STILL
ADVERTISED ESPECIALLY ACROSS THE SOUTHERN HALF OF THE CWA.
DIDN/T CHANGE HIGH TEMPS MUCH FROM PREVIOUS FORECAST...STILL
CALLING FOR A RANGE FROM MID 90S FAR NORTH...UPPER 90S ALONG THE
I-80 CORRIDOR...AND 100-105 ACROSS SEVERAL SOUTHERN COUNTIES
INCLUDING NORTH CENTRAL KS. HOWEVER...WITHIN MANY OF THESE HOTTEST
COUNTIES...ALSO LOWERED DEWPOINTS AT LEAST A FEW DEGREES FROM
PREVIOUS FORECAST PER MET GUIDANCE/RAW NAM SUGGESTION. AS A
RESULT...FORECAST APPARENT TEMPERATURES TOP OUT MAINLY IN THE
100-104 RANGE...WHICH IS JUST BARELY BELOW CRITERIA FOR HEAT
ADVISORY...ALTHOUGH IT MIGHT BE VERY CLOSE. FOR NOW...WILL
CONTINUE TO CARRY AN HWO MENTION OF NEAR-ADVISORY CRITERIA...BUT
NO ACTUAL HEADLINE SEEMS NECESSARY AT THIS POINT. ALONG THESE SAME
LINES...DESPITE RELATIVE HUMIDITY VALUES CRASHING INTO THE 10-20
PERCENT RANGE ACROSS SEVERAL WESTERN COUNTIES IN THE
AFTERNOON...THE SUSTAINED WIND SPEEDS OF 20 MPH NEEDED FOR RED
FLAG WARNING ISSUANCE DON/T APPEAR TO BE IN PLACE...SO NO FIRE
HEADLINES PLANNED.
.LONG TERM...00Z TUESDAY THROUGH SUNDAY. CONCERNS IN THE EXTENDED
CONTINUE TO BE HEAT EARLY...FOLLOWED BY PRECIPITATION CHANCES MID
WEEK...AND THEN MORE HEAT BY THE END OF THE PERIOD.
LONG RANGE MODELS STILL VERY SIMILAR WITH OVERALL PATTERN THROUGH
THE PERIOD. AT THE START OF THE PERIOD...MONDAY EVENING...IT LOOKS
LIKE THERE WILL BE A MID LEVEL SHORT WAVE TROUGH MOVING INTO THE
NORTHERN ROCKIES AND THIS FEATURE SHOULD IMPACT OUR WEATHER TUESDAY
NIGHT AND WEDNESDAY AS IT CROSSES THE NORTHERN PLAINS. THE SOUTHERN
END OF THE MID LEVEL TROUGH AXIS IS SLATED TO MOVE THROUGH OUR CWA
BY WED EVENING WITH RIDGING STARTING TO BUILD OVER THE ROCKIES AT
THAT TIME AND THIS WILL TRANSLATE EAST AND ESTABLISH ITSELF OVER THE
CENTRAL PLAINS GOING INTO NEXT WEEKEND.
SENSIBLE WEATHER SHOULD BE DRY OVERNIGHT MONDAY AND THROUGH MUCH OF
THE DAY ON TUESDAY. AT THE SURFACE...SHOULD BE A WARM FRONT DRAPED
OVER THE NORTHERN CWA AT THE START OF THE PERIOD AND THIS IS SLATED
TO LIFT NORTH OVERNIGHT AS A SURFACE LOW PRESSURE LIFTS FROM SW TO
NE NEBRASKA. ON TUESDAY THE COLD FRONT WILL SLOWLY START TO APPROACH
THE CWA...EXTENDING FROM VTN TO LBF BY 12Z...AND FROM FULLERTON TO
CAMBRIDGE BY 00Z. QUESTION HERE IS HOW LONG WILL WE REMAIN CAPPED
TUESDAY AFTERNOON. LOOKING AT PROGGED 700 MB TEMPS IT WILL BE A
CLOSE CALL IN THE NW WHETHER CONVECTION CAN INITIATE LATE IN THE
AFTERNOON. OVERNIGHT TUESDAY AND INTO THE DAYTIME WED THE MID LEVEL
TROUGH SHOULD PUSH THE SURFACE FRONT THROUGH THE CWA. BY 06Z THE
NE/SW ORIENTED FRONT SHOULD BE ABOUT HALFWAY THROUGH THE CWA...AND
EXPECT IT TO PUSH THROUGH THE CWA SHORTLY AFTER SUNRISE.
MODEL GENERATED QPF SHOWING SOME DIFFERENCES IN WHERE THE BULK OF
THE RAIN WILL FALL. THE NAM AND THE GFS BOTH SHOW THE RAIN STARTING
ALONG THE SURFACE FRONT...BUT THE NAM HAS THE BULK OF THE OVERNIGHT
RAIN MAINLY NORTH OF OUR CWA ALONG THE MID LEVEL FRONT. LATEST GFS
CONTINUES THE TREND OF KEEPING THE RAIN FURTHER SOUTH
OVERNIGHT...PRODUCING MORE ACROSS OUR CWA. IT ALSO SHOWS THE MID
LEVEL FRONT FURTHER SOUTH AND MUCH CLOSER TO THE SURFACE FRONT. THE
OLD EC SHOWED MORE OF A NORTHERN SOLUTION AND WILL TAKE A LATE LOOK
AT THE 12Z RUN BEFORE MAKING A FINAL CALL. CHECKING OTHER
MODELS...BOTH THE SREF AND GEM SUPPORT A MORE NORTHERN SOLUTION
WHILE THE UKMET MORE IN LINE WITH THE SOUTHERN GFS SOLUTION.
WED AND THU STILL SHOWING UNCERTAINTY IN THE DETAILS AS LATEST GFS
NOW BRINGS ANOTHER MID LEVEL WAVE THROUGH THE NORTHERN PLAINS ON
THURSDAY NIGHT WHILE THE OLD EC AND MOST OF THE OTHER MODEL
SOLUTIONS NOT SHOWING THIS AT ALL. THUS WILL LEAN TOWARD CONSENSUS
AND WHILE IT MAY NOT BE TOTALLY DRY ON THURSDAY...BELIEVE THE GFS IS
OVERDONE...ESPECIALLY GIVE THE HIGH DEWPOINT BIAS AS OF LATE
CANNOT RULE OUT SEVERE POSSIBILITIES TUESDAY NIGHT THROUGH WEDNESDAY
STARTING IN THE NW PART OF THE CWA TUESDAY LATE AFTN/EVE AS MUCAPE
AND DEEP LAYER SHEAR BOTH RESPECTABLE VIA THE EC. SHEAR MUCH LESS IN
THE SOUTHERN PART OF THE CWA. BY WED LATE AFTERNOON BEST SEVERE
PARAMETERS LOOK TO BE SOUTH OF THE CWA ACCORDING TO OLD EC RUN BUT A
LITTLE CHANGE IN TIMING COULD PUT PART OF OUR CWA IN THE PICTURE.
FRIDAY THROUGH SUNDAY LOOKS DRY AS BOTH SOLUTIONS CONTINUE TO BUILD
IN A STOUT RIDGE BY THEN. ONLY FLY IN THE OINTMENT WOULD BE IF WE
END UP WITH A FEW RIDGE RUNNERS AROUND THE RING OF FIRE THAT CLIP A
PART OF OUR AREA. THAT DOES NOT LOOK TO BE THE CASE AT THIS
TIME...BUT HAS BEEN SOMEWHAT COMMON THE PAST COUPLE OF YEARS WITH
THIS TYPE OF JULY PATTERN SO WILL NEED TO BE WATCHED.
&&
.AVIATION...18Z KGRI TAF. VFR CEILING AND VISIBILITY FORECAST
THROUGH THE PERIOD...WITH ONLY SOME PASSING MID-HIGH CLOUDS AND
ESSENTIALLY ZERO RISK OF THUNDERSTORMS. AS A DEEPENING SURFACE LOW
PRESSURE SYSTEM PASSES BY TO THE NORTH...STEADY SOUTH BREEZES WILL
PERSIST THROUGH AT LEAST THE FIRST 15 HOURS OF THE PERIOD...WITH
GUST POTENTIAL TO AROUND 26KT. THERE COULD BE BIT OF A LULL IN
THESE GUSTS DURING THE EVENING...BUT HAVE NOT DEPICTED THIS FOR
NOW. OVERNIGHT...MAY HAVE TO CONSIDER ADDING LOW LEVEL WIND
SHEAR...AS SOUTHERLY SPEEDS INCREASE TO AROUND 50KT BETWEEN
1500-2000 FT AGL. HOWEVER...WILL OMIT FOR NOW AS DIRECTIONAL
CHANGE IS FAIRLY MINIMAL...AND THE SPEED DIFFERENCE IS FAIRLY
MARGINAL FOR A FORMAL LOW LEVEL WIND SHEAR MENTION. LATE TONIGHT
INTO MONDAY MORNING...AN APPROACHING SURFACE TROUGH AXIS WILL
DECREASE SURFACE WIND SPEEDS A BIT...AND START TURNING THEM MORE
WESTERLY. TOWARD THE VERY END OF THE PERIOD...A LIGHT NORTHERLY
BREEZE MAY TAKE HOLD BEHIND A WEAK COLD FRONT...BUT WILL DEFER TO
LATER SHIFTS TO ADD THIS WIND SHIFT.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM/AVIATION...PFANNKUCH
LONG TERM...EWALD
AREA FORECAST DISCUSSION
NWS BUFFALO NY
545 PM EDT SUN JUN 17 2012
.SYNOPSIS...
A WEAK FRONTAL BOUNDARY WILL APPROACH THIS EVENING...BRINGING A
ROUND OF SHOWERS AND THUNDERSTORMS TO FAR WESTERN NEW YORK THIS
EVENING. SHOWERS DIMINISH LATE TONIGHT INTO MONDAY AS HIGH PRESSURE
REGAINS CONTROL LATE MONDAY. THIS WILL BRING INCREASINGLY HOT
WEATHER AS THE HIGH SHIFTS EAST OF THE CAROLINAS.
&&
.NEAR TERM /THROUGH MONDAY/...
AS OF 535 PM...AREA RADARS SHOW THE MAIN BAND OF SHOWERS AND
EMBEDDED THUNDERSTORMS TO OUR WEST WEAKENING A LITTLE BIT BUT
STILL HOLDING TOGETHER AS IT PUSHES EAST TOWARD THE CWA...WITH THE
LEADING EDGE NOW RUNNING FROM ROUGHLY ASHTABULA TO BETWEEN LONDON
AND HAMILTON ONTARIO. ASSUMING THIS ACTIVITY MANAGES TO HOLD
TOGETHER...ITS CURRENT MOVEMENT WOULD BRING THE ACTIVITY INTO
CHAUTAUQUA COUNTY AFTER 7 PM...AND EXTREME FAR WESTERN PORTIONS OF
THE NIAGARA FRONTIER BY AROUND 9 PM.
MEANWHILE OUT AHEAD OF THIS LINE...WITH DAYTIME HEATING A SECOND
AND MUCH NARROWER LINE OF SCATTERED CONVECTION HAS FORMED ALONG A
REGION OF VERY SUBTLE LOW LEVEL CONVERGENCE LOCATED TO THE EAST AND
NORTHEAST OF BUFFALO...WITH THIS ACTIVITY NOW SLOWLY LIFTING NORTHEAST
ACROSS GENESEE AND ORLEANS COUNTIES. THESE SHOWERS AND STORMS WILL
CONTINUE TO LIFT NORTHEAST AND OUT INTO LAKE ONTARIO OVER THE
COURSE OF THE NEXT FEW HOURS...POSSIBLY CLIPPING PART OF MONROE
COUNTY IN THE PROCESS. MEANWHILE SOUTH OF THIS...LINGERING LOW
LEVEL CONVERGENCE MAY HELP TO TRIGGER SOME ADDITIONAL SCATTERED
SHOWERS AND STORMS OVER THE MIDDLE AND UPPER PORTIONS OF THE
GENESEE VALLEY.
HAVE UPDATED THE FORECAST TO KEEP IT IN LINE WITH THESE EXPECTED
TRENDS...WHICH HAS RESULTED IN A FASTER ARRIVAL OF LOWER-END
CONVECTIVE CHANCES ACROSS THE GENESEE VALLEY AND WESTERN FINGER
LAKES EARLY THIS EVENING. OTHER THAN THAT THERE HAS BEEN LITTLE
OVERALL CHANGE ASIDE TO SOME MINOR ADJUSTMENTS IN TIMING. THE FULL
MID AFTERNOON NEAR TERM DISCUSSION FOLLOWS BELOW...
AN UPPER LEVEL TROF NORTH OF LAKE SUPERIOR WILL DRIVE A SHORTWAVE
INTO WESTERN NEW YORK THIS EVENING. RADAR SHOWED SHOWERS AND
THUNDERSTORMS ACROSS NORTH-CENTRAL OHIO MID-AFTERNOON. THERE IS A STRONG
CONSENSUS AMONG MOST RUNS THE RGEM/NAM12/GFS/HRRR THAT THIS AREA
WILL MOVE INTO FAR WESTERN NEW YORK THIS EVENING. IN
GENERAL...EXPECT SHOWERS TO ADVECT INTO THE REGION...CROSSING THE
NY/PA LINE BETWEEN 600 PM AND 800 PM...THEN REACHING BUFFALO AND
VICINITY DURING THE EVENING HOURS...THEN WEAKENING AS IT APPROACHES
ROCHESTER LATE THIS EVENING. THE HRRR APPEARS TO HAVE A GOOD HANDLE
ON THIS...AND GIVEN GENERAL SUPPORT OF OTHER MODELS...THE
FORECAST WILL CONTINUE TO BE FAIRLY CLOSE TO A SMOOTHED HRRR
FORECAST OF THE PROGRESSION OF THESE SHOWERS. CONFIDENCE SUPPORTS
CATEGORICAL POPS IN CHAUTAUQUA COUNTY...WHERE LOCALLY HEAVY RAINFALL
MAY BE AN ISSUE DUE TO SLOW MOVING CELLS. WHILE FAR WESTERN NEW YORK
SHOULD AVERAGE BETWEEN A QUARTER AND A HALF INCH OF RAIN...LOCALLY
HIGHER AMOUNTS ARE POSSIBLE IN CHAUTAUQUA COUNTY.
THERE ALSO MAY BE SOME SHOWERS WHICH BREAK OUT AHEAD OF THIS ACROSS
LAKE ONTARIO...ALONG A LAKE-BREEZE INDUCED CONVERGENCE ZONE ON THE
LAKE...HOWEVER CONFIDENCE IN THIS IS DEVELOPING IS LOWER...AND WOULD
TEND TO IMPACT OFFSHORE AND ONTARIO PROVINCE ANYWAYS.
THE SEVERE WEATHER POTENTIAL APPEARS MINIMAL ACROSS WESTERN NEW YORK
AS MODEL CAPES REMAIN 500 J/KG OR LOWER...AND ONLY MODEST WIND SHEAR
AS WINDS ABOVE 700MB ARE FORECAST TO BE AROUND 20 KTS. THIS WEAK
FLOW COULD LEAD TO LOCALLY HEAVY RAINFALL...AS UPSTREAM PRECIPITABLE
WATER VALUES ARE RUNNING AROUND 1.50 INCHES...AND ARE FORECAST TO
INCREASE TO 1.75 INCHES. WHILE THE CHANCE FOR FLOODING IS STILL
RELATIVELY SMALL...HAVE ADDED A MENTION OF HEAVY RAIN INTO THE HWO
FOR CHAUTAUQUA COUNTY.
THE BOUNDARY WILL PRETTY MUCH WASH OUT THROUGH MONDAY MORNING...WITH
LINGERING SHOWERS LIKELY TO TAPER OFF. THERE IS A SLIGHT CHANCE FOR
INSTABILITY SHOWERS ON MONDAY AFTERNOON...NEAR WHAT IS LEFT OF THE
BOUNDARY...BUT THESE CHANCES APPEAR MINIMAL AS INSTABILITY WILL BE MINIMAL.
TEMPERATURES TONIGHT WILL ONLY DROP INTO THE 60S IN MOST
LOCATIONS...AS WIND AND CLOUDS LIMIT RADIATIONAL COOLING.
TEMPERATURES SHOULD THEN WARM TO THE LOWER 80S IN MOST LOCATIONS FOR
MONDAY...WITH A PRIMARILY CLOUDY SKIES IN THE MORNING EXPECTED TO
GIVE WAY TO INCREASING SUN DURING THE AFTERNOON HOURS.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
VERY WARM (HOT) AND RATHER HUMID CONDITIONS WILL BE THE RULE THROUGH
THIS PERIOD AS THE UPPER LEVEL RIDGE STRENGTHENS OVER THE OHIO
VALLEY AND LOWER GREAT LAKES.
AT THE SURFACE...HIGH PRESSURE WILL BE ANCHORED OFF THE EAST COAST
WHILE LOW PRESSURE LIFTS NORTHEAST ACROSS JAMES BAY MONDAY NIGHT AND
TUESDAY. A 40 TO 50 KNOT LOW LEVEL THAT IS FORECAST TO SURGE EAST OF
THE LOW MONDAY NIGHT WILL STAY NORTH OF NEW YORK STATE. AS A
RESULT...ANY SHOWERS THAT FORM IN THE VICINITY OF THE JET SHOULD
STAY MAINLY TO OUR NORTH.
THE SOUTHERLY FLOW BETWEEN THE EAST COAST HIGH AND THE DEPARTING LOW
WILL RESULT IN VERY MILD TEMPERATURES MONDAY NIGHT. LOCATIONS ALONG
THE LAKE ERIE PLAIN MAY NOT GET MUCH BELOW 70F...WHILE THE REST OF
THE AREA SEES TEMPERATURES RANGING THROUGH THE 60S.
AS THE UPPER LEVEL LOW OVER QUEBEC MOVES TO THE EAST ON TUESDAY...A
SECOND TROUGH WILL PUSH EAST ACROSS THE NORTHERN ROCKIES AND INTO
THE NORTHERN PLAINS. THE DEEPENING NORTHERN PLAINS LOW WILL CAUSE
THE RIDGE OF THE EASTERN HALF OF THE COUNTRY TO STRENGTHEN FURTHER
AND EXPAND NORTH INTO THE LOWER LAKES. SINCE THE CENTER OF THIS
RIDGE WILL BE IN THE VCNTY OF WEST VIRGINIA...WE WILL LOOK TO THE
MIDWEST FOR OUR UPCOMING SPELL OF OPPRESSIVE HEAT. THE INCREASING
SYNOPTIC SCALE SUBSIDENCE WILL COMBINE WITH MID LEVEL WARMING (H7 OF
10C) TO PUT A CAP ON ANY CONVECTION. WITH 850 MB TEMPERATURES
FORECAST TO WARM INTO THE UPPER TEENS...SURFACE TEMPERATURES WILL
WARM WELL INTO THE 80S...WITH LOWER 90S LIKELY ACROSS A GOOD PART OF
THE GENESEE VALLEY AND LAKE ONTARIO PLAIN.
BREEZY CONDITIONS MAY DEVELOP DOWNWIND OF LAKE ERIE TUESDAY
AFTERNOON AS THE LARGE SCALE SYNOPTIC SCALE FLOW VEERS MORE TO THE
SOUTHWEST AROUND THE BUILDING UPPER LEVEL RIDGE. THE SOUTHWEST
BREEZE WILL BRING SOME MINOR RELIEF FROM THE HEAT TO AREAS LOCATED
IMMEDIATELY DOWNWIND OF THE LAKE.
WARM AND HUMID CONDITIONS WILL CONTINUE TUESDAY NIGHT WITH THE CORE
OF THE UPPER LEVEL RIDGE EXPECTED TO BE IN PLACE OVER PA AND NEW
YORK STATE. SURFACE TEMPERATURES WILL SETTLE ONLY INTO THE LOWER 70S
ACROSS MOST OF THE AREA NORTH OF THE SOUTHERN TIER. WITH SURFACE
DEWPOINTS FORECAST TO BE IN THE MID AND UPPER 60S...HAZE AND PATCHY
FOG MAY BECOME MORE WIDESPREAD.
WEDNESDAY STILL LOOKS LIKE IT WILL BE THE HOTTEST DAY OF THE WEEK
WITH THE UPPER RIDGE PARKED RIGHT OVER PA AND NEW YORK.
H85 TEMPS HOVERING AROUND 20C WILL EASILY SUPPORT AFTERNOON TEMPS IN
THE 90S. THE ONLY EXCEPTIONS WILL BE NEAR THE IMMEDIATE LAKE SHORES
AND ACROSS THE HIGHEST TERRAIN. WOULD NOT BE SURPRISED TO SEE
READINGS IN THE MID 90S ACROSS THE GENESEE VALLEY AND ACROSS PARTS
OF THE NIAGARA FRONTIER. HEAT INDEX VALUES WILL LIKELY RANGE FROM 95
TO 100 FOR SEVERAL HOURS. THIS HAS ALREADY BEEN ADDRESSED IN THE
HAZARDOUS WEATHER OUTLOOK PRODUCT (HWO).
SULTRY CONDITIONS WILL CONTINUE ACROSS THE CWA WEDNESDAY NIGHT.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
THURSDAY WILL BE THE TRANSITION DAY BETWEEN THE LONG ADVERTISED
SPELL OF MID SUMMER HEAT AND HUMIDITY AND COOLER CONDITIONS TO
FOLLOW LATER IN THE WEEK.
THURSDAY WILL STILL BE QUITE WARM AND HUMID...BUT THE PERSISTENT
RIDGE WILL BEGIN TO FLATTEN AS A DIGGING UPPER LEVEL TROUGH HEADS
EAST ACROSS SOUTHERN ONTARIO AND QUEBEC. THE ASSOCIATED COLD FRONT
FRONT WILL PUSH ACROSS OUR AREA DURING THE AFTERNOON AND
EVENING...ACCOMPANIED BY A FEW SHOWERS AND THUNDERSTORMS.
OTHERWISE...MEDIUM RANGE OPERATIONAL AND ENSEMBLE PACKAGES ARE IN
GOOD AGREEMENT THAT COOLER MORE COMFORTABLE WEATHER WILL MOVE IN
FRIDAY THROUGH SUNDAY AS A SIGNIFICANT PATTERN CHANGE SETS UP ACROSS
NORTH AMERICA.
A POTENT SHORTWAVE OVER NORTHERN ONTARIO AT THE START OF THIS PERIOD
WILL LIFT NORTHEAST ACROSS NORTHERN QUEBEC...WHILE A DEEP CLOSED LOW
WILL DIG SOUTHEAST ALONG THE COAST OF BRITISH COLUMBIA. THIS PROCESS
WILL PUMP UP A RIDGE OVER THE INTERMOUNTAIN WEST WHILE DOWNSTREAM
TROUGHING CAN BE EXPECTED OVER THE GREAT LAKES AND NORTHEAST.
THE RESULT WILL BE NEAR TO BELOW AVERAGE TEMPERATURES FOR OUR REGION
FRIDAY THROUGH SUNDAY WITH NOTABLY LOWER HUMIDITY LEVELS. WHILE THE
PASSING OF THE AFOREMENTIONED COLD FRONT MAY GENERATE A FEW MORE
SHOWERS/THUNDERSTORMS EARLY THURSDAY NIGHT...THE MAJORITY OF THIS
PERIOD SHOULD BE RAIN FREE. SFC HIGH PRESSURE WILL BE OVER THE GREAT
LAKES/UPPER OHIO VALLEY FOR MUCH OF FRIDAY AND SATURDAY.
A WARM FRONT LIFTING NORTH FROM THE OHIO VALLEY WILL LIKELY BRING AN
INCREASE IN CLOUDS SATURDAY NIGHT AND SUNDAY. CANNOT RULE OUT THE
POSSIBILITY OF A FEW SHOWERS WITH THE APPROACHING FRONT...BUT WILL
INDICATE JUST A SLIGHT CHANCE OF MEASURABLE PCPN FOR NOW.
&&
.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
EXPECT MAINLY VFR CONDITIONS THROUGH THE REMAINDER OF THE
AFTERNOON...AS SHOWERS AND THUNDERSTORMS SHOULD HOLD OFF UNTIL
NEAR 00Z. THE BEST CHANCE FOR CONVECTION WILL BE AT JHW...WITH A
GOOD CHANCE FOR THUNDERSTORMS AT BUF/IAG. WILL FOCUS MAINLY ON AN
EVENING TIMING...AS A LINE ACROSS OHIO GRADUALLY TRACKS TOWARD THE
REGION. THUNDERSTORMS MAY BRIEFLY DROP VSBY TO 2SM OR LESS IN
HEAVY RAIN.
SHOWERS AND THUNDERSTORMS WILL WEAKEN AS THEY MOVE EAST LATER
TONIGHT...AS THEY ENCOUNTER THE SLOWLY DEPARTING RIDGE. EXPECT VFR
CONDITIONS TO PERSIST AT ROC/ART...BUT INCREASING MOISTURE MAY
RESULT IN SOME ISSUES AT BUF/IAG/JHW. THERE MAY BE SOME LIGHT FOG
AT BUF/IAG/JHW...BUT WINDS SHOULD PREVENT ANYTHING DENSE FROM
DEVELOPING. THERE COULD IFR/MVFR CIGS MAY DEVELOP LATE TONIGHT AND
LINGER INTO MONDAY MORNING. ANOTHER CONCERN FOR TONIGHT IS THE
PASSAGE OF A 30 TO 35 KT LOW LEVEL JET. THIS WILL PRODUCE SOME
MARGINAL SHEAR AT SOME SITES. THIS IS MARGINAL FOR INCLUSION IN
TAFS AT ALL SITES...WITH ART THE ONLY LOCATION TO MEET CRITERIA
THOUGH OTHER SITES WILL BE CLOSE.
EXPECT IMPROVING CONDITIONS ON MONDAY...WITH LIFTING CIGS...AND
LINGERING SHOWERS TAPERING OFF.
OUTLOOK...
MONDAY NIGHT THROUGH WEDNESDAY...MAINLY VFR.
THURSDAY...VFR/MVFR. A CHANCE OF SHOWERS AND THUNDERSTORMS.
&&
.MARINE...
SOUTHERLY WINDS INCREASING ON THE LAKES THIS MORNING AHEAD OF AN
APPROACHING FRONT. THIS FRONT WILL CROSS THE LAKES LATE TONIGHT WITH
SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING AHEAD OF IT DURING
THE AFTERNOON/EVENING HOURS ACROSS FAR WESTERN NY. THE SOUTHERLY WINDS
WILL MAKE FOR CHOPPIER WATERS...THOUGH HIGHER WAVES WILL BE CONFINED
TO THE NORTHERN PORTIONS OF THE LAKES. WINDS WILL SLACKEN SOMEWHAT
BEHIND THE FRONT ON MONDAY WITH WINDS GENERALLY REMAINING 15 KTS OR
LOWER THROUGH MIDWEEK.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL/JJR
SHORT TERM...TJP
LONG TERM...TJP
AVIATION...APFFEL
MARINE...APFFEL/TJP
AREA FORECAST DISCUSSION
NWS BUFFALO NY
330 PM EDT SUN JUN 17 2012
.SYNOPSIS...
A WEAK FRONTAL BOUNDARY WILL APPROACH THIS EVENING...BRINGING A
ROUND OF SHOWERS AND THUNDERSTORMS TO FAR WESTERN NEW YORK THIS
EVENING. SHOWERS DIMINISH LATE TONIGHT INTO MONDAY AS HIGH PRESSURE
REGAINS CONTROL LATE MONDAY. THIS WILL BRING INCREASINGLY HOT
WEATHER AS THE HIGH SHIFTS EAST OF THE CAROLINAS.
&&
.NEAR TERM /THROUGH MONDAY/...
AN UPPER LEVEL TROF NORTH OF LAKE SUPERIOR WILL DRIVE A SHORTWAVE
INTO WESTERN NEW YORK THIS EVENING. RADAR SHOWED SHOWERS AND
THUNDERSTORMS ACROSS NORTH-CENTRAL OHIO MID-AFTERNOON. THERE IS A STRONG
CONSENSUS AMONG MOST RUNS THE RGEM/NAM12/GFS/HRRR THAT THIS AREA
WILL MOVE INTO FAR WESTERN NEW YORK THIS EVENING. IN
GENERAL...EXPECT SHOWERS TO ADVECT INTO THE REGION...CROSSING THE
NY/PA LINE BETWEEN 600 PM AND 800 PM...THEN REACHING BUFFALO AND
VICINITY DURING THE EVENING HOURS...THEN WEAKENING AS IT APPROACHES
ROCHESTER LATE THIS EVENING. THE HRRR APPEARS TO HAVE A GOOD HANDLE
ON THIS...AND GIVEN GENERAL SUPPORT OF OTHER MODELS...THE
FORECAST WILL CONTINUE TO BE FAIRLY CLOSE TO A SMOOTHED HRRR
FORECAST OF THE PROGRESSION OF THESE SHOWERS. CONFIDENCE SUPPORTS
CATEGORICAL POPS IN CHAUTAUQUA COUNTY...WHERE LOCALLY HEAVY RAINFALL
MAY BE AN ISSUE DUE TO SLOW MOVING CELLS. WHILE FAR WESTERN NEW YORK
SHOULD AVERAGE BETWEEN A QUARTER AND A HALF INCH OF RAIN...LOCALLY
HIGHER AMOUNTS ARE POSSIBLE IN CHAUTAUQUA COUNTY.
THERE ALSO MAY BE SOME SHOWERS WHICH BREAK OUT AHEAD OF THIS ACROSS
LAKE ONTARIO...ALONG A LAKE-BREEZE INDUCED CONVERGENCE ZONE ON THE
LAKE...HOWEVER CONFIDENCE IN THIS IS DEVELOPING IS LOWER...AND WOULD
TEND TO IMPACT OFFSHORE AND ONTARIO PROVINCE ANYWAYS.
THE SEVERE WEATHER POTENTIAL APPEARS MINIMAL ACROSS WESTERN NEW YORK
AS MODEL CAPES REMAIN 500 J/KG OR LOWER...AND ONLY MODEST WIND SHEAR
AS WINDS ABOVE 700MB ARE FORECAST TO BE AROUND 20 KTS. THIS WEAK
FLOW COULD LEAD TO LOCALLY HEAVY RAINFALL...AS UPSTREAM PRECIPITABLE
WATER VALUES ARE RUNNING AROUND 1.50 INCHES...AND ARE FORECAST TO
INCREASE TO 1.75 INCHES. WHILE THE CHANCE FOR FLOODING IS STILL
RELATIVELY SMALL...HAVE ADDED A MENTION OF HEAVY RAIN INTO THE HWO
FOR CHAUTAUQUA COUNTY.
THE BOUNDARY WILL PRETTY MUCH WASH OUT THROUGH MONDAY MORNING...WITH
LINGERING SHOWERS LIKELY TO TAPER OFF. THERE IS A SLIGHT CHANCE FOR
INSTABILITY SHOWERS ON MONDAY AFTERNOON...NEAR WHAT IS LEFT OF THE
BOUNDARY...BUT THESE CHANCES APPEAR MINIMAL AS INSTABILITY WILL BE MINIMAL.
TEMPERATURES TONIGHT WILL ONLY DROP INTO THE 60S IN MOST
LOCATIONS...AS WIND AND CLOUDS LIMIT RADIATIONAL COOLING.
TEMPERATURES SHOULD THEN WARM TO THE LOWER 80S IN MOST LOCATIONS FOR
MONDAY...WITH A PRIMARILY CLOUDY SKIES IN THE MORNING EXPECTED TO
GIVE WAY TO INCREASING SUN DURING THE AFTERNOON HOURS.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
VERY WARM (HOT) AND RATHER HUMID CONDITIONS WILL BE THE RULE THROUGH
THIS PERIOD AS THE UPPER LEVEL RIDGE STRENGTHENS OVER THE OHIO
VALLEY AND LOWER GREAT LAKES.
AT THE SURFACE...HIGH PRESSURE WILL BE ANCHORED OFF THE EAST COAST
WHILE LOW PRESSURE LIFTS NORTHEAST ACROSS JAMES BAY MONDAY NIGHT AND
TUESDAY. A 40 TO 50 KNOT LOW LEVEL THAT IS FORECAST TO SURGE EAST OF
THE LOW MONDAY NIGHT WILL STAY NORTH OF NEW YORK STATE. AS A
RESULT...ANY SHOWERS THAT FORM IN THE VICINITY OF THE JET SHOULD
STAY MAINLY TO OUR NORTH.
THE SOUTHERLY FLOW BETWEEN THE EAST COAST HIGH AND THE DEPARTING LOW
WILL RESULT IN VERY MILD TEMPERATURES MONDAY NIGHT. LOCATIONS ALONG
THE LAKE ERIE PLAIN MAY NOT GET MUCH BELOW 70F...WHILE THE REST OF
THE AREA SEES TEMPERATURES RANGING THROUGH THE 60S.
AS THE UPPER LEVEL LOW OVER QUEBEC MOVES TO THE EAST ON TUESDAY...A
SECOND TROUGH WILL PUSH EAST ACROSS THE NORTHERN ROCKIES AND INTO
THE NORTHERN PLAINS. THE DEEPENING NORTHERN PLAINS LOW WILL CAUSE
THE RIDGE OF THE EASTERN HALF OF THE COUNTRY TO STRENGTHEN FURTHER
AND EXPAND NORTH INTO THE LOWER LAKES. SINCE THE CENTER OF THIS
RIDGE WILL BE IN THE VCNTY OF WEST VIRGINIA...WE WILL LOOK TO THE
MIDWEST FOR OUR UPCOMING SPELL OF OPPRESSIVE HEAT. THE INCREASING
SYNOPTIC SCALE SUBSIDENCE WILL COMBINE WITH MID LEVEL WARMING (H7 OF
10C) TO PUT A CAP ON ANY CONVECTION. WITH 850 MB TEMPERATURES
FORECAST TO WARM INTO THE UPPER TEENS...SURFACE TEMPERATURES WILL
WARM WELL INTO THE 80S...WITH LOWER 90S LIKELY ACROSS A GOOD PART OF
THE GENESEE VALLEY AND LAKE ONTARIO PLAIN.
BREEZY CONDITIONS MAY DEVELOP DOWNWIND OF LAKE ERIE TUESDAY
AFTERNOON AS THE LARGE SCALE SYNOPTIC SCALE FLOW VEERS MORE TO THE
SOUTHWEST AROUND THE BUILDING UPPER LEVEL RIDGE. THE SOUTHWEST
BREEZE WILL BRING SOME MINOR RELIEF FROM THE HEAT TO AREAS LOCATED
IMMEDIATELY DOWNWIND OF THE LAKE.
WARM AND HUMID CONDITIONS WILL CONTINUE TUESDAY NIGHT WITH THE CORE
OF THE UPPER LEVEL RIDGE EXPECTED TO BE IN PLACE OVER PA AND NEW
YORK STATE. SURFACE TEMPERATURES WILL SETTLE ONLY INTO THE LOWER 70S
ACROSS MOST OF THE AREA NORTH OF THE SOUTHERN TIER. WITH SURFACE
DEWPOINTS FORECAST TO BE IN THE MID AND UPPER 60S...HAZE AND PATCHY
FOG MAY BECOME MORE WIDESPREAD.
WEDNESDAY STILL LOOKS LIKE IT WILL BE THE HOTTEST DAY OF THE WEEK
WITH THE UPPER RIDGE PARKED RIGHT OVER PA AND NEW YORK.
H85 TEMPS HOVERING AROUND 20C WILL EASILY SUPPORT AFTERNOON TEMPS IN
THE 90S. THE ONLY EXCEPTIONS WILL BE NEAR THE IMMEDIATE LAKE SHORES
AND ACROSS THE HIGHEST TERRAIN. WOULD NOT BE SURPRISED TO SEE
READINGS IN THE MID 90S ACROSS THE GENESEE VALLEY AND ACROSS PARTS
OF THE NIAGARA FRONTIER. HEAT INDEX VALUES WILL LIKELY RANGE FROM 95
TO 100 FOR SEVERAL HOURS. THIS HAS ALREADY BEEN ADDRESSED IN THE
HAZARDOUS WEATHER OUTLOOK PRODUCT (HWO).
SULTRY CONDITIONS WILL CONTINUE ACROSS THE CWA WEDNESDAY NIGHT.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
THURSDAY WILL BE THE TRANSITION DAY BETWEEN THE LONG ADVERTISED
SPELL OF MID SUMMER HEAT AND HUMIDITY AND COOLER CONDITIONS TO
FOLLOW LATER IN THE WEEK.
THURSDAY WILL STILL BE QUITE WARM AND HUMID...BUT THE PERSISTENT
RIDGE WILL BEGIN TO FLATTEN AS A DIGGING UPPER LEVEL TROUGH HEADS
EAST ACROSS SOUTHERN ONTARIO AND QUEBEC. THE ASSOCIATED COLD FRONT
FRONT WILL PUSH ACROSS OUR AREA DURING THE AFTERNOON AND
EVENING...ACCOMPANIED BY A FEW SHOWERS AND THUNDERSTORMS.
OTHERWISE...MEDIUM RANGE OPERATIONAL AND ENSEMBLE PACKAGES ARE IN
GOOD AGREEMENT THAT COOLER MORE COMFORTABLE WEATHER WILL MOVE IN
FRIDAY THROUGH SUNDAY AS A SIGNIFICANT PATTERN CHANGE SETS UP ACROSS
NORTH AMERICA.
A POTENT SHORTWAVE OVER NORTHERN ONTARIO AT THE START OF THIS PERIOD
WILL LIFT NORTHEAST ACROSS NORTHERN QUEBEC...WHILE A DEEP CLOSED LOW
WILL DIG SOUTHEAST ALONG THE COAST OF BRITISH COLUMBIA. THIS PROCESS
WILL PUMP UP A RIDGE OVER THE INTERMOUNTAIN WEST WHILE DOWNSTREAM
TROUGHING CAN BE EXPECTED OVER THE GREAT LAKES AND NORTHEAST.
THE RESULT WILL BE NEAR TO BELOW AVERAGE TEMPERATURES FOR OUR REGION
FRIDAY THROUGH SUNDAY WITH NOTABLY LOWER HUMIDITY LEVELS. WHILE THE
PASSING OF THE AFOREMENTIONED COLD FRONT MAY GENERATE A FEW MORE
SHOWERS/THUNDERSTORMS EARLY THURSDAY NIGHT...THE MAJORITY OF THIS
PERIOD SHOULD BE RAIN FREE. SFC HIGH PRESSURE WILL BE OVER THE GREAT
LAKES/UPPER OHIO VALLEY FOR MUCH OF FRIDAY AND SATURDAY.
A WARM FRONT LIFTING NORTH FROM THE OHIO VALLEY WILL LIKELY BRING AN
INCREASE IN CLOUDS SATURDAY NIGHT AND SUNDAY. CANNOT RULE OUT THE
POSSIBILITY OF A FEW SHOWERS WITH THE APPROACHING FRONT...BUT WILL
INDICATE JUST A SLIGHT CHANCE OF MEASURABLE PCPN FOR NOW.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
EXPECT MAINLY VFR CONDITIONS THROUGH THE REMAINDER OF THE
AFTERNOON...AS SHOWERS AND THUNDERSTORMS SHOULD HOLD OFF UNTIL
NEAR 00Z. THE BEST CHANCE FOR CONVECTION WILL BE AT JHW...WITH A
GOOD CHANCE FOR THUNDERSTORMS AT BUF/IAG. WILL FOCUS MAINLY ON AN
EVENING TIMING...AS A LINE ACROSS OHIO GRADUALLY TRACKS TOWARD THE
REGION. THUNDERSTORMS MAY BRIEFLY DROP VSBY TO 2SM OR LESS IN
HEAVY RAIN.
SHOWERS AND THUNDERSTORMS WILL WEAKEN AS THEY MOVE EAST LATER
TONIGHT...AS THEY ENCOUNTER THE SLOWLY DEPARTING RIDGE. EXPECT VFR
CONDITIONS TO PERSIST AT ROC/ART...BUT INCREASING MOISTURE MAY
RESULT IN SOME ISSUES AT BUF/IAG/JHW. THERE MAY BE SOME LIGHT FOG
AT BUF/IAG/JHW...BUT WINDS SHOULD PREVENT ANYTHING DENSE FROM
DEVELOPING. THERE COULD IFR/MVFR CIGS MAY DEVELOP LATE TONIGHT AND
LINGER INTO MONDAY MORNING. ANOTHER CONCERN FOR TONIGHT IS THE
PASSAGE OF A 30 TO 35 KT LOW LEVEL JET. THIS WILL PRODUCE SOME
MARGINAL SHEAR AT SOME SITES. THIS IS MARGINAL FOR INCLUSION IN
TAFS AT ALL SITES...WITH ART THE ONLY LOCATION TO MEET CRITERIA
THOUGH OTHER SITES WILL BE CLOSE.
EXPECT IMPROVING CONDITIONS ON MONDAY...WITH LIFTING CIGS...AND
LINGERING SHOWERS TAPERING OFF.
OUTLOOK...
MONDAY NIGHT THROUGH WEDNESDAY...MAINLY VFR.
THURSDAY...VFR/MVFR. A CHANCE OF SHOWERS AND THUNDERSTORMS.
&&
.MARINE...
SOUTHERLY WINDS INCREASING ON THE LAKES THIS MORNING AHEAD OF AN
APPROACHING FRONT. THIS FRONT WILL CROSS THE LAKES LATE TONIGHT WITH
SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING AHEAD OF IT DURING
THE AFTERNOON/EVENING HOURS ACROSS FAR WESTERN NY. THE SOUTHERLY WINDS
WILL MAKE FOR CHOPPIER WATERS...THOUGH HIGHER WAVES WILL BE CONFINED
TO THE NORTHERN PORTIONS OF THE LAKES. WINDS WILL SLACKEN SOMEWHAT
BEHIND THE FRONT ON MONDAY WITH WINDS GENERALLY REMAINING 15 KTS OR
LOWER THROUGH MIDWEEK.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL
SHORT TERM...TJP
LONG TERM...TJP
AVIATION...APFFEL
MARINE...APFFEL/TJP
AREA FORECAST DISCUSSION
NWS BUFFALO NY
328 PM EDT SUN JUN 17 2012
.SYNOPSIS...
HIGH PRESSURE OVER THE REGION WILL RETREAT EASTWARD TODAY AHEAD
OF AN APPROACHING FRONT. THIS FRONT WILL BRING A THREAT OF SHOWERS
AND THUNDERSTORMS AS IT CROSSES THE AREA MAINLY TONIGHT. LINGERING
SHOWERS WILL DISAPPEAR BY MONDAY AS HIGH PRESSURE ONCE AGAIN RE-
ESTABLISHES ITSELF OVER THE NORTHEASTERN UNITED STATES BRINGING
VERY WARM AND DRY WEATHER THAT WILL LAST THROUGH MIDWEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
AN UPPER LEVEL RIDGE WILL GRADUALLY SHIFT EASTWARD ACROSS NEW
ENGLAND AS A SHORTWAVE APPROACHES FROM THE UPPER LAKES. SHOWERS
WHICH HAD DEVELOPED WELL OUT AHEAD OF THIS SHORTWAVE THIS MORNING
HAVE WEAKENED CONSIDERABLY AS THEY ENCOUNTERED THE UPPER RIDGE.
EXPECT THIS TRENT TO CONTINUE...WITH THE MAIN IMPACT FROM THIS
BEING LEFT OVER CLOUD COVER. MOST AREAS WILL REMAIN DRY THROUGH
THE REMAINDER OF THE AFTERNOON...WITH MAINLY SUNNY SKIES EAST OF
ROCHESTER. MEANWHILE...A SOUTHERLY FLOW SHOULD HELP DOWNSLOPE
NORTH OF THE THRUWAY...ALLOWING TEMPERATURES TO RISE IN TO THE
LOWER TO MID 80S...DESPITE SOME CLOUD COVER.
MEANWHILE...A POTENT UPPER LEVEL SHORTWAVE NORTH OF LAKE
SUPERIOR...WILL DRIVE A SHORTWAVE TOWARD THE REGION LATE THIS
AFTERNOON...WHICH SHOULD ENTER WESTERN NEW YORK THIS EVENING.
THERE IS A STRONG CONSENSUS AMONG MOST RUNS THE
RGEM/NAM12/GFS/HRRR THAT THIS WILL SPARK SOME SHOWERS AND
THUNDERSTORMS WHICH WILL EVENTUALLY REACH FAR WESTERN NEW YORK
THIS EVENING. AS FORECAST...THUNDERSTORMS HAVE DEVELOPED ACROSS
WESTERN OHIO EARLY THESE AFTERNOON...WITH THE HRRR APPEARING TO
CAPTURE THIS FEATURE QUITE WELL. IN GENERAL...EXPECT THIS LINE TO
ADVECT INTO THE REGION...CROSSING THE NY/PA LINE BETWEEN 600 PM
AND 800 PM...THEN REACHING BUFFALO AND VICINITY DURING THE EVENING
HOURS. THERE ALSO MAY BE SOME SHOWERS WHICH BREAK OUT AHEAD OF
THIS ACROSS LAKE ONTARIO...ALONG A LAKE-BREEZE INDUCED CONVERGENCE
ZONE ON THE LAKE...HOWEVER CONFIDENCE IN THIS IS DEVELOPING IS
LOWER...AND WOULD TEND TO IMPACT OFFSHORE ANYWAYS. SUPPORTED BY
RADAR...HAVE UPPED POPS IN WESTERN PORTIONS THIS EVENING...AND
SLOWED TIMING A BIT TO REFLECT THIS SLIGHTLY LATER ARRIVAL TIME.
THE SEVERE WEATHER POTENTIAL APPEARS MINIMAL ACROSS WESTERN NEW
YORK AS MODEL CAPES REMAIN 500 J/KG OR LOWER. WIND SHEAR VALUES
ALSO NOT IMPRESSIVE WITH LESS THAN 20 KTS ABOVE 700MB PER NAM
BUFKIT SOUNDINGS. ONLY WEAK POP-UP ORDINARY CELL CONVECTION
EXPECTED WITH TOPS LESS THAN 30KFT. THIS SAID...SOME CELLS COULD
BRING LOCALLY HEAVY RAINFALL...AS UPSTREAM PRECIPITABLE WATER
VALUES ARE RUNNING AROUND 1.50 INCHES...AND ARE FORECAST TO
INCREASE TO 1.75 INCHES.
SOME SCATTERED CONVECTION WILL CONTINUE OVERNIGHT...WEAKENING TO
MORE GENERIC SHOWERS AS THE NIGHT WEARS ON. WINDS WILL STAY
BREEZY THROUGH THE NIGHT FROM THE SOUTH AND LOW TEMPS WILL AGAIN
BE ABOVE NORMAL ONLY FALLING INTO THE LOWER TO MIDDLE 60S.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
SEVERAL SHORTWAVES CROSSING THE CANADIAN PRAIRIES AND THE UPPER
GREAT LAKES WILL HELP TO FLATTEN A STRONG H5 RIDGE THAT HAD BEEN IN
PLACE SINCE THE MIDDLE OF LAST WEEK. AS THIS ENERGY LIFT ACROSS
NORTHERN QUEBEC ON MONDAY...AN ASSOCIATED SFC FRONTAL BOUNDARY WILL
PUSH EAST OF OUR REGION. HOPEFULLY THIS SUBTLE FEATURE WILL PRODUCE
A LITTLE BENEFICIAL RAIN IN THE PROCESS.
IN ITS WAKE...OUR ATTENTION WILL RETURN TO A MORE VIGOROUS SHORTWAVE
THAT IS CURRENTLY DIGGING SOUTHEAST FROM THE GULF OF ALASKA. AS THIS
POTENT FEATURE DROPS ACROSS THE PACIFIC NORTHWEST ON MONDAY...AND
IDAHO/MONTANA ON TUESDAY...IT WILL HELP A DOWNSTREAM RIDGE TO `POP`
ACROSS THE EASTERN HALF OF THE COUNTRY. THIS H5 RIDGE IS FORECAST TO
AMPLIFY TO 594DM OVER THE UPPER OHIO VALLEY BY MIDWEEK WHILE 20C AIR
AT H85 WILL BE PUMPED FROM THE MID WEST TO OUR FORECAST AREA. LET
THERE BE NO DOUBT...WE ARE IN STORE FOR AT LEAST A PAIR OF FAIRLY
OPPRESSIVE DAYS WITH HIGHS COMMONLY IN THE 90S. MORE ON THAT IN A
MOMENT.
THE AFOREMENTIONED FRONTAL BOUNDARY WILL WASHOUT ACROSS CENTRAL AND
EASTERN NEW YORK ON MONDAY WHILE A WEAKLY DIVERGENT UPPER LEVEL FLOW
WILL GIVE WAY TO THE ONSET OF RISING H5 HGTS. WHILE THIS WILL LEAD
TO DRY WEATHER FOR THE BULK OF THE REGION...WEAK LOW LEVEL
CONVERGENCE WITHIN A MOISTURE RICH AIRMASS (PWAT 1.5") MAY BE ENOUGH
TO PRODUCE A SHOWER OR THUNDERSTORM...MAINLY EAST OF ROCHESTER. THE
CONVECTION MAY HAVE TO OVERCOME A MID LEVEL 1 DEG CAP...BUT SBCAPES
OF 500-1000 J/KG AND VERY WEAK SYNOPTIC FORCING WILL CERTAINLY BE
ENOUGH TO WARRANT KEEPING THEM IN THE FORECAST. IT IS ALSO WORTH
NOTING THAT THE ENVIRONMENTAL WINDS WILL BE MAINLY UNDER 15 KNOTS
THROUGH 25K FT...SO WHILE SEVERE WEATHER IS NOT A CONCERN...ANY
CONVECTION THAT FIRES UP COULD PRODUCE RELATIVELY SLOW MOVING
DOWNPOURS. OTHERWISE THE DAY WILL FEATURE PARTLY SUNNY WARM AND
HUMID CONDITIONS WITH HIGHS GENERALLY IN THE LOW TO MID 80S.
ANOTHER WEAK BOUNDARY WILL PRESS ACROSS THE REGION MONDAY NIGHT...
AND WHILE A SHOWER CANNOT BE RULED OUT...STEADY HGT RISES AND THE
REMOVAL OF THE DIURNALLY INDUCED INSTABILITY SHOULD KEEP US RAIN
FREE. IT WILL BE A WARM NIGHT THOUGH AS A SOUTHERLY 30KT LOW LEVEL
JET WILL HELP TO HOLD UP OUR OVERNIGHT LOWS. TEMPERATURES WILL
STRUGGLE TO DROP BELOW 70 ACROSS THE LOWER TERRAIN OF THE LAKE
PLAINS...WHILE THE REMAINDER OF THE REGION WILL EXPERIENCE LOWS IN
THE LOW TO MID 60S.
STRONG RIDGING WILL THEN EXPAND OVER THE EASTERN HALF OF THE COUNTRY
ON TUESDAY AS A POTENT SHORTWAVE WILL MAKE ITS WAY OUT ACROSS THE
HIGH PLAINS OF MONTANA AND WYOMING. SINCE THE CENTER OF THIS
BLOSSOMING RIDGE WILL BE IN THE VCNTY OF WEST VIRGINIA...WE WILL
LOOK TO THE MID WEST FOR OUR UPCOMING SPELL OF OPPRESSIVE HEAT. THIS
IS WHERE H85 TEMPS OF 18 TO 20C WILL SPREAD EAST ACROSS THE LOWER
GREAT LAKES TO OUR REGION. THE INCREASING SYNOPTIC SCALE SUBSIDENCE
WILL COMBINE WITH MID LEVEL WARMING (H7 OF 10C) TO PUT A CAP ON ANY
CONVECTION...LEAVING US WITH ENOUGH SUNSHINE TO PROPEL OUR AFTERNOON
TEMPS INTO THE UPPER 80S...AND IN MANY CASES...INTO THE LOW 90S.
TUESDAY NIGHT WILL FEATURE THE DRONE OF AIR CONDITIONERS AS IT WILL
BE SULTRY BY ANY STANDARDS. SFC TEMPS WILL ONLY SETTLE INTO THE
LOWER 70S ACROSS A LARGE PORTION OF OUR FORECAST AREA AS THE CORE OF
THE STRONG H5 RIDGE WILL BE JUST TO OUR SOUTH WHILE H85 TEMPS OF 18C
WILL BE ACCOMPANIED BY LIGHT SFC WINDS. THE ONLY RELIEF AWAY FROM
THOSE AIR CONDITIONERS WILL BE IN SOME OF THE DEEPER SRN TIER
VALLEYS WHERE ONE MAY BE LUCKY ENOUGH TO EXPERIENCE TEMPS NEAR 65...
ALONG WITH SOME MURKY FOG.
WEDNESDAY WILL SIMPLY BE HOT AND OPPRESSIVE AS THE AXIS OF THE 594
RIDGE (+2 STD) WILL BE DIRECTLY OVER OUR REGION. H85 TEMPS OF 20C
WILL EASILY SUPPORT AFTERNOON TEMPS IN THE 90S. THE ONLY EXCEPTIONS
WILL BE NEAR THE IMMEDIATE LAKE SHORES AND ACROSS THE HIGHEST
TERRAIN. WOULD NOT BE SURPRISED TO SEE READINGS IN THE MID 90S
ACROSS THE GENESEE VALLEY AND ACROSS PARTS OF THE NIAGARA FRONTIER.
HEAT INDEX VALUES WILL LIKELY RANGE FROM 95 TO 100 FOR SEVERAL
HOURS...SO WILL HIT THIS BE ADDRESSED IN THE HAZARDOUS WEATHER
OUTLOOK PRODUCT (HWO).
IF YOU LIKE THE FORECAST FOR TUESDAY NIGHT (SEE ABV)...YOU WILL LOVE
WEDNESDAY NIGHT. IT SHOULD BE EVERY BIT AS UNCOMFORTABLE AS TEMPS
WILL BARELY DROP BELOW 75 ACROSS THE LAKE PLAINS. AT LEAST TOMATO
PLANTS LOVE THIS KIND OF WEATHER.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
THURSDAY WILL BE THE LAST DAY OF THIS SPELL OF MID SUMMER HEAT AND
HUMIDITY...AS OUR CONTROLLING H5 RIDGE WILL FLATTEN AND MOVE OFF THE
COAST IN RESPONSE TO A DIGGING TROUGH OVER THE UPPER GREAT LAKES.
TEMPERATURES THURSDAY AFTERNOON WILL ONCE AGAIN CLIMB INTO THE UPPER
80S TO LOWER 90S...BUT CONVECTION SHOULD HOLD OFF UNTIL LATE
AFTERNOON OR EVENING.
OTHERWISE...MEDIUM RANGE OPERATIONAL AND ENSEMBLE PACKAGES ARE IN
GOOD AGREEMENT THAT COOLER MORE COMFORTABLE WEATHER WILL MOVE IN
DURING THIS PERIOD AS NORTH AMERICA WILL EXPERIENCE A MAJOR PATTERN
CHANGE.
A POTENT SHORTWAVE OVER NORTHERN ONTARIO AT THE START OF THIS PERIOD
WILL LIFT NORTHEAST ACROSS NORTHERN QUEBEC...WHILE A DEEP CLOSED LOW
WILL DIG SOUTHEAST ALONG THE COAST OF BRITISH COLUMBIA. THIS PROCESS
WILL PUMP UP A RIDGE OVER THE INTERMOUNTAIN WEST WHILE DOWNSTREAM
TROUGHING CAN BE EXPECTED OVER THE GREAT LAKES AND NORTHEAST.
THE RESULT WILL BE NEAR TO BELOW NORMAL TEMPERATURES FOR OUR REGION
FRIDAY AND SATURDAY WITH NOTABLY LOWER HUMIDITY LEVELS. WHILE THE
PASSING OF A FRONTAL SYSTEM THURSDAY NIGHT COULD SPARK SOME
SHOWER/THUNDERSTORM ACTIVITY...THE MAJORITY OF THIS PERIOD SHOULD BE
RAIN FREE. SFC HIGH PRESSURE WILL BE OVER THE GREAT LAKES/UPPER OHIO
VALLEY FOR MUCH OF FRIDAY AND SATURDAY.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
EXPECT MAINLY VFR CONDITIONS THROUGH THE REMAINDER OF THE
AFTERNOON...AS SHOWERS AND THUNDERSTORMS SHOULD HOLD OFF UNTIL
NEAR 00Z. THE BEST CHANCE FOR CONVECTION WILL BE AT JHW...WITH A
GOOD CHANCE FOR THUNDERSTORMS AT BUF/IAG. WILL FOCUS MAINLY ON AN
EVENING TIMING...AS A LINE ACROSS OHIO GRADUALLY TRACKS TOWARD THE
REGION. THUNDERSTORMS MAY BRIEFLY DROP VSBY TO 2SM OR LESS IN
HEAVY RAIN.
SHOWERS AND THUNDERSTORMS WILL WEAKEN AS THEY MOVE EAST LATER
TONIGHT...AS THEY ENCOUNTER THE SLOWLY DEPARTING RIDGE. EXPECT VFR
CONDITIONS TO PERSIST AT ROC/ART...BUT INCREASING MOISTURE MAY
RESULT IN SOME ISSUES AT BUF/IAG/JHW. THERE MAY BE SOME LIGHT FOG
AT BUF/IAG/JHW...BUT WINDS SHOULD PREVENT ANYTHING DENSE FROM
DEVELOPING. THERE COULD IFR/MVFR CIGS MAY DEVELOP LATE TONIGHT AND
LINGER INTO MONDAY MORNING. ANOTHER CONCERN FOR TONIGHT IS THE
PASSAGE OF A 30 TO 35 KT LOW LEVEL JET. THIS WILL PRODUCE SOME
MARGINAL SHEAR AT SOME SITES. THIS IS MARGINAL FOR INCLUSION IN
TAFS AT ALL SITES...WITH ART THE ONLY LOCATION TO MEET CRITERIA
THOUGH OTHER SITES WILL BE CLOSE.
EXPECT IMPROVING CONDITIONS ON MONDAY...WITH LIFTING CIGS...AND
LINGERING SHOWERS TAPERING OFF.
OUTLOOK...
MONDAY NIGHT THROUGH WEDNESDAY...VFR.
THURSDAY...VFR/MVFR. A CHANCE OF SHOWERS AND THUNDERSTORMS.
&&
.MARINE...
SOUTHERLY WINDS INCREASING ON THE LAKES THIS MORNING AHEAD OF AN
APPROACHING FRONT. THIS FRONT WILL CROSS THE LAKES LATE TONIGHT WITH
SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING AHEAD OF IT DURING
THE AFTERNOON/EVENING HOURS ACROSS FAR WESTERN NY. THE SOUTHERLY WINDS
WILL MAKE FOR CHOPPIER WATERS...THOUGH HIGHER WAVES WILL BE CONFINED
TO THE NORTHERN PORTIONS OF THE LAKES. WINDS WILL SLACKEN SOMEWHAT
BEHIND THE FRONT ON MONDAY WITH WINDS GENERALLY REMAINING 15 KTS OR
LOWER THROUGH MIDWEEK.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL
SHORT TERM...TJP
LONG TERM...TJP
AVIATION...APFFEL
MARINE...APFFEL/TJP
AREA FORECAST DISCUSSION
NWS BUFFALO NY
157 PM EDT SUN JUN 17 2012
.SYNOPSIS...
HIGH PRESSURE OVER THE REGION WILL RETREAT EASTWARD TODAY AHEAD
OF AN APPROACHING FRONT. THIS FRONT WILL BRING A THREAT OF SHOWERS
AND THUNDERSTORMS AS IT CROSSES THE AREA MAINLY TONIGHT. LINGERING
SHOWERS WILL DISAPPEAR BY MONDAY AS HIGH PRESSURE ONCE AGAIN RE-
ESTABLISHES ITSELF OVER THE NORTHEASTERN UNITED STATES BRINGING
VERY WARM AND DRY WEATHER THAT WILL LAST THROUGH MIDWEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AN UPPER LEVEL RIDGE WILL GRADUALLY SHIFT EASTWARD ACROSS NEW
ENGLAND AS A SHORTWAVE APPROACHES FROM THE UPPER LAKES. SHOWERS
WHICH HAD DEVELOPED WELL OUT AHEAD OF THIS SHORTWAVE THIS MORNING
HAVE WEAKENED CONSIDERABLY AS THEY ENCOUNTERED THE UPPER RIDGE.
EXPECT THIS TRENT TO CONTINUE...WITH THE MAIN IMPACT FROM THIS
BEING LEFT OVER CLOUD COVER. MOST AREAS WILL REMAIN DRY THROUGH
THE REMAINDER OF THE AFTERNOON...WITH MAINLY SUNNY SKIES EAST OF
ROCHESTER. MEANWHILE...A SOUTHERLY FLOW SHOULD HELP DOWNSLOPE
NORTH OF THE THRUWAY...ALLOWING TEMPERATURES TO RISE IN TO THE
LOWER TO MID 80S...DESPITE SOME CLOUD COVER.
MEANWHILE...A POTENT UPPER LEVEL SHORTWAVE NORTH OF LAKE
SUPERIOR...WILL DRIVE A SHORTWAVE TOWARD THE REGION LATE THIS
AFTERNOON...WHICH SHOULD ENTER WESTERN NEW YORK THIS EVENING.
THERE IS A STRONG CONSENSUS AMONG MOST RUNS THE
RGEM/NAM12/GFS/HRRR THAT THIS WILL SPARK SOME SHOWERS AND
THUNDERSTORMS WHICH WILL EVENTUALLY REACH FAR WESTERN NEW YORK
THIS EVENING. AS FORECAST...THUNDERSTORMS HAVE DEVELOPED ACROSS
WESTERN OHIO EARLY THESE AFTERNOON...WITH THE HRRR APPEARING TO
CAPTURE THIS FEATURE QUITE WELL. IN GENERAL...EXPECT THIS LINE TO
ADVECT INTO THE REGION...CROSSING THE NY/PA LINE BETWEEN 600 PM
AND 800 PM...THEN REACHING BUFFALO AND VICINITY DURING THE EVENING
HOURS. THERE ALSO MAY BE SOME SHOWERS WHICH BREAK OUT AHEAD OF
THIS ACROSS LAKE ONTARIO...ALONG A LAKE-BREEZE INDUCED CONVERGENCE
ZONE ON THE LAKE...HOWEVER CONFIDENCE IN THIS IS DEVELOPING IS
LOWER...AND WOULD TEND TO IMPACT OFFSHORE ANYWAYS. SUPPORTED BY
RADAR...HAVE UPPED POPS IN WESTERN PORTIONS THIS EVENING...AND
SLOWED TIMING A BIT TO REFLECT THIS SLIGHTLY LATER ARRIVAL TIME.
THE SEVERE WEATHER POTENTIAL APPEARS MINIMAL ACROSS WESTERN NEW
YORK AS MODEL CAPES REMAIN 500 J/KG OR LOWER. WIND SHEAR VALUES
ALSO NOT IMPRESSIVE WITH LESS THAN 20 KTS ABOVE 700MB PER NAM
BUFKIT SOUNDINGS. ONLY WEAK POP-UP ORDINARY CELL CONVECTION
EXPECTED WITH TOPS LESS THAN 30KFT. THIS SAID...SOME CELLS COULD
BRING LOCALLY HEAVY RAINFALL...AS UPSTREAM PRECIPITABLE WATER
VALUES ARE RUNNING AROUND 1.50 INCHES...AND ARE FORECAST TO
INCREASE TO 1.75 INCHES.
SOME SCATTERED CONVECTION WILL CONTINUE OVERNIGHT...WEAKENING TO
MORE GENERIC SHOWERS AS THE NIGHT WEARS ON. WINDS WILL STAY
BREEZY THROUGH THE NIGHT FROM THE SOUTH AND LOW TEMPS WILL AGAIN
BE ABOVE NORMAL ONLY FALLING INTO THE LOWER TO MIDDLE 60S.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
SEVERAL SHORTWAVES CROSSING THE CANADIAN PRAIRIES AND THE UPPER
GREAT LAKES WILL HELP TO FLATTEN A STRONG H5 RIDGE THAT HAD BEEN IN
PLACE SINCE THE MIDDLE OF LAST WEEK. AS THIS ENERGY LIFT ACROSS
NORTHERN QUEBEC ON MONDAY...AN ASSOCIATED SFC FRONTAL BOUNDARY WILL
PUSH EAST OF OUR REGION. HOPEFULLY THIS SUBTLE FEATURE WILL PRODUCE
A LITTLE BENEFICIAL RAIN IN THE PROCESS.
IN ITS WAKE...OUR ATTENTION WILL RETURN TO A MORE VIGOROUS SHORTWAVE
THAT IS CURRENTLY DIGGING SOUTHEAST FROM THE GULF OF ALASKA. AS THIS
POTENT FEATURE DROPS ACROSS THE PACIFIC NORTHWEST ON MONDAY...AND
IDAHO/MONTANA ON TUESDAY...IT WILL HELP A DOWNSTREAM RIDGE TO `POP`
ACROSS THE EASTERN HALF OF THE COUNTRY. THIS H5 RIDGE IS FORECAST TO
AMPLIFY TO 594DM OVER THE UPPER OHIO VALLEY BY MIDWEEK WHILE 20C AIR
AT H85 WILL BE PUMPED FROM THE MID WEST TO OUR FORECAST AREA. LET
THERE BE NO DOUBT...WE ARE IN STORE FOR AT LEAST A PAIR OF FAIRLY
OPPRESSIVE DAYS WITH HIGHS COMMONLY IN THE 90S. MORE ON THAT IN A
MOMENT.
THE AFOREMENTIONED FRONTAL BOUNDARY WILL WASHOUT ACROSS CENTRAL AND
EASTERN NEW YORK ON MONDAY WHILE A WEAKLY DIVERGENT UPPER LEVEL FLOW
WILL GIVE WAY TO THE ONSET OF RISING H5 HGTS. WHILE THIS WILL LEAD
TO DRY WEATHER FOR THE BULK OF THE REGION...WEAK LOW LEVEL
CONVERGENCE WITHIN A MOISTURE RICH AIRMASS (PWAT 1.5") MAY BE ENOUGH
TO PRODUCE A SHOWER OR THUNDERSTORM...MAINLY EAST OF ROCHESTER. THE
CONVECTION MAY HAVE TO OVERCOME A MID LEVEL 1 DEG CAP...BUT SBCAPES
OF 500-1000 J/KG AND VERY WEAK SYNOPTIC FORCING WILL CERTAINLY BE
ENOUGH TO WARRANT KEEPING THEM IN THE FORECAST. IT IS ALSO WORTH
NOTING THAT THE ENVIRONMENTAL WINDS WILL BE MAINLY UNDER 15 KNOTS
THROUGH 25K FT...SO WHILE SEVERE WEATHER IS NOT A CONCERN...ANY
CONVECTION THAT FIRES UP COULD PRODUCE RELATIVELY SLOW MOVING
DOWNPOURS. OTHERWISE THE DAY WILL FEATURE PARTLY SUNNY WARM AND
HUMID CONDITIONS WITH HIGHS GENERALLY IN THE LOW TO MID 80S.
ANOTHER WEAK BOUNDARY WILL PRESS ACROSS THE REGION MONDAY NIGHT...
AND WHILE A SHOWER CANNOT BE RULED OUT...STEADY HGT RISES AND THE
REMOVAL OF THE DIURNALLY INDUCED INSTABILITY SHOULD KEEP US RAIN
FREE. IT WILL BE A WARM NIGHT THOUGH AS A SOUTHERLY 30KT LOW LEVEL
JET WILL HELP TO HOLD UP OUR OVERNIGHT LOWS. TEMPERATURES WILL
STRUGGLE TO DROP BELOW 70 ACROSS THE LOWER TERRAIN OF THE LAKE
PLAINS...WHILE THE REMAINDER OF THE REGION WILL EXPERIENCE LOWS IN
THE LOW TO MID 60S.
STRONG RIDGING WILL THEN EXPAND OVER THE EASTERN HALF OF THE COUNTRY
ON TUESDAY AS A POTENT SHORTWAVE WILL MAKE ITS WAY OUT ACROSS THE
HIGH PLAINS OF MONTANA AND WYOMING. SINCE THE CENTER OF THIS
BLOSSOMING RIDGE WILL BE IN THE VCNTY OF WEST VIRGINIA...WE WILL
LOOK TO THE MID WEST FOR OUR UPCOMING SPELL OF OPPRESSIVE HEAT. THIS
IS WHERE H85 TEMPS OF 18 TO 20C WILL SPREAD EAST ACROSS THE LOWER
GREAT LAKES TO OUR REGION. THE INCREASING SYNOPTIC SCALE SUBSIDENCE
WILL COMBINE WITH MID LEVEL WARMING (H7 OF 10C) TO PUT A CAP ON ANY
CONVECTION...LEAVING US WITH ENOUGH SUNSHINE TO PROPEL OUR AFTERNOON
TEMPS INTO THE UPPER 80S...AND IN MANY CASES...INTO THE LOW 90S.
TUESDAY NIGHT WILL FEATURE THE DRONE OF AIR CONDITIONERS AS IT WILL
BE SULTRY BY ANY STANDARDS. SFC TEMPS WILL ONLY SETTLE INTO THE
LOWER 70S ACROSS A LARGE PORTION OF OUR FORECAST AREA AS THE CORE OF
THE STRONG H5 RIDGE WILL BE JUST TO OUR SOUTH WHILE H85 TEMPS OF 18C
WILL BE ACCOMPANIED BY LIGHT SFC WINDS. THE ONLY RELIEF AWAY FROM
THOSE AIR CONDITIONERS WILL BE IN SOME OF THE DEEPER SRN TIER
VALLEYS WHERE ONE MAY BE LUCKY ENOUGH TO EXPERIENCE TEMPS NEAR 65...
ALONG WITH SOME MURKY FOG.
WEDNESDAY WILL SIMPLY BE HOT AND OPPRESSIVE AS THE AXIS OF THE 594
RIDGE (+2 STD) WILL BE DIRECTLY OVER OUR REGION. H85 TEMPS OF 20C
WILL EASILY SUPPORT AFTERNOON TEMPS IN THE 90S. THE ONLY EXCEPTIONS
WILL BE NEAR THE IMMEDIATE LAKE SHORES AND ACROSS THE HIGHEST
TERRAIN. WOULD NOT BE SURPRISED TO SEE READINGS IN THE MID 90S
ACROSS THE GENESEE VALLEY AND ACROSS PARTS OF THE NIAGARA FRONTIER.
HEAT INDEX VALUES WILL LIKELY RANGE FROM 95 TO 100 FOR SEVERAL
HOURS...SO WILL HIT THIS BE ADDRESSED IN THE HAZARDOUS WEATHER
OUTLOOK PRODUCT (HWO).
IF YOU LIKE THE FORECAST FOR TUESDAY NIGHT (SEE ABV)...YOU WILL LOVE
WEDNESDAY NIGHT. IT SHOULD BE EVERY BIT AS UNCOMFORTABLE AS TEMPS
WILL BARELY DROP BELOW 75 ACROSS THE LAKE PLAINS. AT LEAST TOMATO
PLANTS LOVE THIS KIND OF WEATHER.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
THURSDAY WILL BE THE LAST DAY OF THIS SPELL OF MID SUMMER HEAT AND
HUMIDITY...AS OUR CONTROLLING H5 RIDGE WILL FLATTEN AND MOVE OFF THE
COAST IN RESPONSE TO A DIGGING TROUGH OVER THE UPPER GREAT LAKES.
TEMPERATURES THURSDAY AFTERNOON WILL ONCE AGAIN CLIMB INTO THE UPPER
80S TO LOWER 90S...BUT CONVECTION SHOULD HOLD OFF UNTIL LATE
AFTERNOON OR EVENING.
OTHERWISE...MEDIUM RANGE OPERATIONAL AND ENSEMBLE PACKAGES ARE IN
GOOD AGREEMENT THAT COOLER MORE COMFORTABLE WEATHER WILL MOVE IN
DURING THIS PERIOD AS NORTH AMERICA WILL EXPERIENCE A MAJOR PATTERN
CHANGE.
A POTENT SHORTWAVE OVER NORTHERN ONTARIO AT THE START OF THIS PERIOD
WILL LIFT NORTHEAST ACROSS NORTHERN QUEBEC...WHILE A DEEP CLOSED LOW
WILL DIG SOUTHEAST ALONG THE COAST OF BRITISH COLUMBIA. THIS PROCESS
WILL PUMP UP A RIDGE OVER THE INTERMOUNTAIN WEST WHILE DOWNSTREAM
TROUGHING CAN BE EXPECTED OVER THE GREAT LAKES AND NORTHEAST.
THE RESULT WILL BE NEAR TO BELOW NORMAL TEMPERATURES FOR OUR REGION
FRIDAY AND SATURDAY WITH NOTABLY LOWER HUMIDITY LEVELS. WHILE THE
PASSING OF A FRONTAL SYSTEM THURSDAY NIGHT COULD SPARK SOME
SHOWER/THUNDERSTORM ACTIVITY...THE MAJORITY OF THIS PERIOD SHOULD BE
RAIN FREE. SFC HIGH PRESSURE WILL BE OVER THE GREAT LAKES/UPPER OHIO
VALLEY FOR MUCH OF FRIDAY AND SATURDAY.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
EXPECT MAINLY VFR CONDITIONS THROUGH THE REMAINDER OF THE
AFTERNOON...AS SHOWERS AND THUNDERSTORMS SHOULD HOLD OFF UNTIL
NEAR 00Z. THE BEST CHANCE FOR CONVECTION WILL BE AT JHW...WITH A
GOOD CHANCE FOR THUNDERSTORMS AT BUF/IAG. WILL FOCUS MAINLY ON AN
EVENING TIMING...AS A LINE ACROSS OHIO GRADUALLY TRACKS TOWARD THE
REGION. THUNDERSTORMS MAY BRIEFLY DROP VSBY TO 2SM OR LESS IN
HEAVY RAIN.
SHOWERS AND THUNDERSTORMS WILL WEAKEN AS THEY MOVE EAST LATER
TONIGHT...AS THEY ENCOUNTER THE SLOWLY DEPARTING RIDGE. EXPECT VFR
CONDITIONS TO PERSIST AT ROC/ART...BUT INCREASING MOISTURE MAY
RESULT IN SOME ISSUES AT BUF/IAG/JHW. THERE MAY BE SOME LIGHT FOG
AT BUF/IAG/JHW...BUT WINDS SHOULD PREVENT ANYTHING DENSE FROM
DEVELOPING. THERE COULD IFR/MVFR CIGS MAY DEVELOP LATE TONIGHT AND
LINGER INTO MONDAY MORNING. ANOTHER CONCERN FOR TONIGHT IS THE
PASSAGE OF A 30 TO 35 KT LOW LEVEL JET. THIS WILL PRODUCE SOME
MARGINAL SHEAR AT SOME SITES. THIS IS MARGINAL FOR INCLUSION IN
TAFS AT ALL SITES...WITH ART THE ONLY LOCATION TO MEET CRITERIA
THOUGH OTHER SITES WILL BE CLOSE.
EXPECT IMPROVING CONDITIONS ON MONDAY...WITH LIFTING CIGS...AND
LINGERING SHOWERS TAPERING OFF.
OUTLOOK...
MONDAY NIGHT THROUGH WEDNESDAY...VFR.
THURSDAY...VFR/MVFR. A CHANCE OF SHOWERS AND THUNDERSTORMS.
&&
.MARINE...
SOUTHERLY WINDS INCREASING ON THE LAKES THIS MORNING AHEAD OF AN
APPROACHING FRONT. THIS FRONT WILL CROSS THE LAKES LATE TONIGHT WITH
SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING AHEAD OF IT DURING
THE AFTERNOON/EVENING HOURS ACROSS FAR WESTERN NY. THE SOUTHERLY WINDS
WILL MAKE FOR CHOPPIER WATERS...THOUGH HIGHER WAVES WILL BE CONFINED
TO THE NORTHERN PORTIONS OF THE LAKES. WINDS WILL SLACKEN SOMEWHAT
BEHIND THE FRONT ON MONDAY WITH WINDS GENERALLY REMAINING 15 KTS OR
LOWER THROUGH MIDWEEK.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...SMITH
NEAR TERM...APFFEL/SMITH
SHORT TERM...RSH
LONG TERM...RSH
AVIATION...APFFEL
MARINE...APFFEL/RSH/SMITH
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
248 PM CDT SUN JUN 17 2012
.SHORT TERM (TONIGHT-WEDNESDAY)...SEVERE EPISODE POTENTIAL FOR
THE SOUTHERN FORECAST AREA IS INCREASING. THE SOUTHERN FA WILL
CONTINUE TO BECOME MORE UNSTABLE OVER THE NEXT FEW HOURS AS
SOUTHERLY LOW-LEVEL FLOW CONTINUES AHEAD OF SFC TROUGH TO THE
WEST. MLCAPE SHOULD BE AOA 2000 J/KG INTO THE SOUTHERN FA BY 00Z.
SFC LOW AND WARM FRONT WILL LIKELY REMAIN SOUTH...CURRENTLY (20Z)
LOCATED FROM CENTRAL SOUTH DAKOTA INTO SOUTHWEST MINNESOTA. THERE
MAY BE TWO AREAS OF CONVECTIVE DEVELOPMENT BETWEEN 20Z-00Z...ONE
ALONG THE WARM FRONT TO THE SOUTH...AND ANOTHER ACROSS SOUTHEAST
NORTH DAKOTA WHERE STRONG INSTABILITY AND SFC TROUGH INTERSECT.
16Z HRRR SHOWS THIS SCENARIO...WITH ACTIVITY THAT DEVELOPS IN
SOUTHEAST NORTH DAKOTA PROPAGATING EASTWARD INTO THE EVENING. SPC
HAS A MODERATE RISK AREA FOR THIS ACTIVITY. GIVEN CURRENT
MESOANALYSIS...WITH HIGHER LCL HEIGHTS AND WEAKER LOW LEVEL
HELICITY BUT STRONG MID- LEVEL WINDS...MAIN THREATS SHOULD BE
STRONG WINDS AND LARGE HAIL.
LOW-LEVEL SOUTHERLY FLOW WILL CONTINUE TO ADVECT 850MB MOISTURE TO
THE NORTH...ALONG AND EAST OF THE VALLEY INTO THIS EVENING. MOST
MODEL GUIDANCE SUGGESTS 850MB COMPUTED CAPE 1000-1500 J/KG BY 03Z
ACROSS THE SPC SLIGHT RISK AREA. AS FORCING FROM LEFT EXIT REGION
OF STRONG 250MB JET INTERSECTS THIS AREA TO THE NORTH...THE
POTENTIAL FOR STRONG TO SEVERE STORMS WILL INCREASE...LIKELY AFTER
00Z. ALL ACTIVITY SHOULD EXIT THE REGION BY 06Z OR SHORTLY AFTER.
MONDAY-WEDNESDAY...ATTEMPTED TO TREND POPS DOWNWARD IN AREAS WHERE
CHANCES APPEAR MINIMAL. THIS ESPECIALLY TRUE ACROSS THE SOUTHERN
FORECAST AREA ON MONDAY AND THE NORTHERN FA MONDAY NIGHT. THE BEST
CHANCE FOR SHOWERS AND THUNDERSTORMS APPEARS TO BE ON TUESDAY AS
UPPER WAVE MOVES THROUGH FLOW ALOFT.
.LONG TERM (WEDNESDAY NIGHT-SUNDAY)...AN ACTIVE PERIOD REMAINS ON
TRACK FOR THE EXTENDED PERIOD. THE DEVELOPMENT OF SOME STRONG
CYCLONES FOR THE SUMMER SEASON IN THE PLAINS APPEARS POSSIBLE.
THIS MAY PRODUCE A COUPLE ROUNDS OF SIGNIFICANT
PRECIPITATION...ESPECIALLY FOR THE SOUTHERN FORECAST AREA...LATE
IN THE WEEK. HOWEVER...THE EXACT TIMING OF THE THUNDERSTORM
COMPLEXES REMAINS PROBLEMATIC.
A GRADUAL EASTERLY SHIFT IN THE PLACEMENT OF THE UPPER LEVEL RIDGE
INTO THE PLAINS STATES NEXT WEEKEND SHOULD RESULT IN A WARMING TREND
FOR THE EXTENDED PERIOD. THUS...AVERAGE TEMPERATURES ARE NOW
EXPECTED TO NEAR AVERAGE FOR LATE JUNE.
&&
.AVIATION...A THUNDERSTORM THREAT REMAINS THE PRIMARY FORECAST
CONCERN FOR AVIATION PRIMARILY BETWEEN 22Z SUNDAY TO 06Z MONDAY
ACROSS THE FORECAST AREA. SOME OF THE THUNDERSTORMS MAY BE SEVERE
WITH LARGE HAIL...DAMAGING SURFACE WIND GUSTS AROUND 60 KNOTS AND
ISOLATED TORNADOES. THE GREATEST THREAT FOR SEVERE THUNDERSTORMS
IS GENERALLY ALONG AND SOUTH OF A KJMS-KFAR-KPKD LINE. THERE IS
UNCERTAINTY AS TO WHERE AND WHEN THE THUNDERSTORMS WILL
INITIATE...THUS THE PERIOD OF VCTS DESIGNATED IN THE FORECASTS.
AFTER THE SURFACE LOW PRESSURE AREAS MOVES EAST OF THE AREA LATER
TONIGHT...SURFACE WINDS WILL BECOME WESTERLY. CLOUD COVER WILL
SLOWLY DIMINISH FROM WEST TO EAST ACROSS THE FORECAST AREA DURING
THE MORNING HORUS ON MONDAY.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
TG/BRAMER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
230 PM CDT SUN JUN 17 2012
.SHORT TERM...TONIGHT THROUGH MONDAY NIGHT...
THE MAIN FOCUS OF THE SHORT TERM PERIOD IS CONVECTIVE TRENDS/TIMING
AND POTENTIAL FOR SEVERE WEATHER. THE PROSPECTS FOR SEVERE STORMS
APPEAR TO HAVE DIMINISHED...ALTHOUGH CANNOT RULE OUT SOME ISOLATED
LARGE HAIL IN A FEW STORMS. SPC DID DROP THAT AREA FROM THE SLIGHT
RISK AT THE LATE MORNING UPDATE. THE MAIN FOCUS FOR SEVERE STORMS
CONTINUES TO BE THE FAR SOUTHEAST...WHERE A WARM FRONT IS EXPECTED
TO SET UP DURING THE LATE AFTERNOON AND EARLY EVENING. DEWPOINTS
HAVE RISEN INTO THE LOW/MID 60S IN THAT AREA...AND ML CAPE VALUES
COULD EVENTUALLY TOP 2000 J/KG. THE NAM BUFR SOUNDING AT JAMESTOWN
DOES INDICATE SOME WARMER AIR ALOFT THAT COULD INHIBIT STORM
DEVELOPMENT. HOWEVER...THE LATEST HRRR INDICATES STORMS DEVELOPING FROM
WISHEK TO JUD AROUND 4 PM CDT. A FEW SUPERCELLS WOULD NOT BE A
SURPRISE...ALONG WITH POTENTIAL FOR ALL TYPE OF SEVERE WEATHER
INCLUDING VERY LARGE HAIL AND AN ISOLATED TORNADO. STRONG/POSSIBLY
SEVERE STORMS ARE EXPECTED TO EXIT THE SOUTHEAST DURING THE EARLY
EVENING. A FEW SHOWERS OR STORMS ARE POSSIBLE ACROSS THE NORTH
DURING THE DAY MONDAY...ALONG A STALLED FRONTAL BOUNDARY. BY LATE
MONDAY NIGHT...A WARM FRONT IS FORECAST TO LIFT NORTH INTO THE
STATE...AGAIN ACCOMPANIED BY STRONG TO POSSIBLY SEVERE THUNDERSTORMS.
.LONG TERM...TUESDAY THROUGH SUNDAY...
HIGHLIGHTS OF THE EXTENDED FORECAST PERIOD ARE BELOW NORMAL
TEMPERATURES AND PRECIPITATION CHANCES TUESDAY AND WEDNESDAY WITH
TEMPERATURES MODERATING WITH DRIER WEATHER LATER IN THE WEEK.
WHILE SOME MINOR DIFFERENCES EXIST AMONGST THE GUIDANCE
SUITE...THE MODELS ARE IN AGREEMENT ON THE PASSAGE OF A SIGNIFICANT
SHORTWAVE ACROSS THE NORTHERN PLAINS LATE IN THE DAY ON TUESDAY.
HOWEVER...THE BEST INSTABILITY WILL BE ACROSS THE UPPER MISSISSIPPI
VALLEY...WITH NO SEVERE WEATHER ANTICIPATED ACROSS WESTERN AND
CENTRAL NORTH DAKOTA. WIDESPREAD SHOWER ACTIVITY WITH EMBEDDED
THUNDERSTORMS WILL BE THE MOST LIKELY MODE OF PRECIPITATION ON
TUESDAY. HARD TO RULE OUT AT LEAST ISOLATED SHOWERS CWA WIDE
WEDNESDAY WITH RATHER COOL TEMPERATURES ALOFT AND THE JET STREAM
POSITIONED ACROSS THE DAKOTAS. HIGH TEMPERATURES ARE FORECAST TO
REBOUND BACK TO NORMAL VALUES BY FRIDAY AS AN UPPER LEVEL RIDGE
BUILDS INTO THE CENTRAL CONUS. CHANCES FOR THUNDER RETURN BY NEXT
WEEKEND AS DEEPER MOISTURE IS ADVECTED INTO THE NORTHERN PLAINS.
&&
.AVIATION...
AS OF 19 UTC...AN OCCLUDING FRONT HAD PASSED THROUGH KMOT AND KBIS.
THE BEST CHANCE FOR SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING
WILL BE AHEAD OF THE FRONT...WITH KJMS THE MOST LIKELY TERMINAL TO
BE IMPACTED ACROSS CENTRAL NORTH DAKOTA. ISOLATED TO SCATTERED
THUNDERSTORMS ARE POSSIBLE FURTHER WEST THIS AFTERNOON THROUGH
SUNSET...WITH THE POTENTIAL FOR SHOWER AND THUNDERSTORM ACTIVITY TO
LINGER INTO TOMORROW ESPECIALLY AT KISN AND KMOT. WIND GUSTS OF 25
TO 30 KTS WILL ALSO BE POSSIBLE AT KJMS...KDIK AND KBIS ON MONDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...KINNEY
LONG TERM/AVIATION...AYD
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
633 PM EDT SUN JUN 17 2012
.SYNOPSIS...
A WEAKENING COLD FRONT IS EXPECTED TO MOVE ACROSS NORTHERN OHIO
AND NW PA THIS THIS EVENING BEFORE STALLING OVER CENTRAL OHIO
TONIGHT. THE FRONT WILL DISSIPATE BY TUESDAY AS HIGH PRESSURE
STRENGTHENS OVER THE MIDDLE ATLANTIC. A STRONG HIGH WILL BE
OVERHEAD FOR MIDWEEK.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
COLD FRONT CONTINUING TO MAKE ONLY SLOW PROGRESS THROUGH NW OHIO
THIS EVENING. BULK OF SHOWERS AND THUNDERSTORMS NOW PUSHING EAST
OF I-71 AS OF 2230Z BUT WILL CONTINUE THROUGH THE REMAINDER OF THE
FORECAST AREA THROUGH 00-02Z. THE WESTERN THIRD OF THE FORECAST
WILL REMAIN MOSTLY DRY THROUGH TONIGHT WITH THE EXCEPTION OF THE
FAR SOUTHWEST WHERE THERE MAY BE SOME ISOLATED SHOWERS OVERNIGHT.
OVERALL LITTLE CHANGES TO FORECAST WORDING...JUST SOME TIMING
ADJUSTMENTS IN GRIDS. NO MAJOR CHANGES TO TEMPS. PREVIOUS
DISCUSSION BELOW.
TRIED TO TIME IT ACROSS THE AREA...LIKELY GETTING OUT OF NW PA
AROUND MIDNIGHT. HRRR DID WELL TIMING THIS INTO THE CLE METRO AREA
AND HAVE FOLLOWED CLOSELY TO THAT TO TIME IT ACROSS THE REST OF
THE AREA. WINDS WILL SHIFT TO THE WEST WITH THE PASSAGE OF THE
FRONT. LOWS IN THE 60S.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/...
WHAT IS LEFT OF THE FRONT WILL GET A LITTLE PUSH NORTH MONDAY AND
HAVE CONTINUED A LOW CHANCE MENTION OF SHOWERS/TS. IT WILL BE
WARMER AGAIN...ESPECIALLY ACROSS THE WEST HALF WITH HIGHS GETTING
BACK INTO THE UPPER 80S. RIDGE REALLY BUILDS FOR MID WEEK AND
WILL GET BACK INTO THE 90S FOR MUCH OF THE AREA. HUMIDITY WILL BE
UP TOO...SO IT WILL FEEL UNCOMFORTABLE.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
MODELS IN AGREEMENT BREAKING DOWN MID WEEK UPPER RIDGE ACROSS THE
OHIO VALLEY AND BY THURSDAY IT SHOULD BE MOVING OFF THE MID ATLANTIC
COAST WITH A ZONAL FLOW DROPPING SOUTH ACROSS THE AREA. TO OUR
NORTH AN UPPER LOW WILL BE MOVING ACROSS HUDSON BAY AND THE SURFACE
SYSTEM WILL HAVE A TRAILING COLD FRONT THAT WILL MOVE THROUGH THE
AREA THURSDAY AFTERNOON. GLFMX MOISTURE APPEARS TO BE CLOSED OFF BY
HIGH PRESSURE ACROSS THE SOUTHEASTERN STATES SO SYSTEM SHOULD
HAVE LIMITED MOISTURE. STILL ENOUGH MOISTURE FOR TSTMS TO
ACCOMPANY THE FRONT SO WILL HAVE CHANCE POPS FOR THE AFTERNOON
THURSDAY INTO THURSDAY EVENING. FRIDAY THE FRONT WILL STALL OUT IN
THE LOWER OHIO VALLEY WITH A SURFACE HIGH ACROSS THE AREA. WILL
KEEP FORECAST DRY...SIDING MORE WITH THE ECMWF. SATURDAY MODELS
REDEVELOP AN UPPER RIDGE ACROSS THE NATIONS MID SECTION WITH A
NORTHWEST GRADIENT ALOFT ACROSS OHIO AND THE GREAT LAKES. A WARM
FRONT WILL BE STRENGTHENING ACROSS THE UPPER MIDWEST...AS THE
FRONT WHICH PASSED THROUGH THE AREA THURSDAY BEGINS TO MOVE
NORTHEAST. BOTH MODELS HINTING AT CONVECTION/SHORT WAVE MOVING
INTO THE AREA FROM ACROSS THE GREAT LAKES IN THE NORTHWEST FLOW.
WILL HAVE CHANCE POPS FOR NORTHEAST OHIO AND NORTHWEST PA SATURDAY
AND A SLIGHT CHANCE SUNDAY AS BY THEN THE VERY WARM AIR RETURNS
WITH THE BUILDING UPPER RIDGE.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
NUMEROUS SHOWERS AND THUNDERSTORMS ACROSS NRN OHIO AND NWRN PA
THIS AFTERNOON WILL DECREASE IN COVERAGE THIS EVENING AS DRIER AIR
MOVES IN FROM THE WNW AND UPPER SUPPORT MOVES EAST. EXPECT AN
EVENTUAL CLEAR OUT/BREAK UP IN THE WEST HOWEVER ACROSS THE EAST
ENOUGH LOW LEVEL MOISTURE SHOULD REMAIN IN PLACE OVERNIGHT FOR A
MVFR STRATUS DECK TO DEVELOP ALONG WITH SOME EARLY MORNING FOG.
COULD SEE EARLY MORNING FOG DEVELOPMENT WEST AS WELL. MONDAY
MORNING THIS WILL BURN OFF FOR A VFR DAY OUTSIDE OF ANY LEFTOVER
ISOLATED CONVECTION.
.OUTLOOK...NON VFR POSSIBLE MAINLY IN WIDELY SCT CONVECTION MONDAY
AFTERNOON/EVENING.
&&
.MARINE...
WEAK COLD FRONT WILL MOVE ACROSS THE LAKE THIS EVENING BRINGING
SHOWERS AND THUNDERSTORMS TO THE LAKE. THE FRONT WILL STALL OVER OR
JUST SOUTH OF THE LAKE OVERNIGHT BEFORE RETURNING AS A WARM FRONT
MONDAY. THIS WILL BRING ANOTHER CHANCE OF THUNDERSTORMS TO THE
LAKE. WINDS WILL BE FROM THE SOUTHWEST TONIGHT AT 10 TO 20 KNOTS
AND AGAIN MONDAY BEHIND THE WARM FRONT. TUESDAY THROUGH WEDNESDAY
WINDS WILL DIMINISH TO 10 KNOTS OF LESS MOST PLACES AS HIGH PRESSURE
BUILDS ACROSS THE LAKE FROM THE EAST. ANOTHER COLD FRONT WILL MOVE
ACROSS THE LAKE FROM THE NORTHWEST THURSDAY AND WILL BRING ANOTHER
CHANCE OF THUNDERSTORMS. WAVES WILL REMAIN BELOW 4 FEET THROUGH THE
PERIOD.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...OUDEMAN
NEAR TERM...ABE/OUDEMAN
SHORT TERM...OUDEMAN
LONG TERM...TK
AVIATION...TK
MARINE...TK
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
329 PM EDT SUN JUN 17 2012
.SYNOPSIS...
A WEAKENING COLD FRONT IS EXPECTED TO MOVE ACROSS NORTHERN OHIO
AND NW PA THIS THIS EVENING BEFORE STALLING OVER CENTRAL OHIO
TONIGHT. THE FRONT WILL DISSIPATE BY TUESDAY AS HIGH PRESSURE
STRENGTHENS OVER THE MIDDLE ATLANTIC. A STRONG HIGH WILL BE
OVERHEAD FOR MIDWEEK.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
AS OF 19Z COLD FRONT HAS MADE IT TO THE OHIO BORDER...SLOWING AND
CONTINUING TO WEAKEN AS IS SETTLES SOUTHEAST TONIGHT. BROKEN LINE
OF SHOWERS AND THUNDERSTORMS WILL SHIFT EAST ACROSS THE AREA LATE
THIS AFTERNOON AND EVENING. NOT MUCH REASON TO SUSPECT ANYTHING
OTHER THAN GARDEN VARIETY TS. TRIED TO TIME IT ACROSS THE
AREA...LIKELY GETTING OUT OF NW PA AROUND MIDNIGHT. HRRR DID WELL
TIMING THIS INTO THE CLE METRO AREA AND HAVE FOLLOWED CLOSELY TO
THAT TO TIME IT ACROSS THE REST OF THE AREA. WINDS WILL SHIFT TO
THE WEST WITH THE PASSAGE OF THE FRONT. LOWS IN THE 60S.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/...
WHAT IS LEFT OF THE FRONT WILL GET A LITTLE PUSH NORTH MONDAY AND
HAVE CONTINUED A LOW CHANCE MENTION OF SHOWERS/TS. IT WILL BE
WARMER AGAIN...ESPECIALLY ACROSS THE WEST HALF WITH HIGHS GETTING
BACK INTO THE UPPER 80S. RIDGE REALLY BUILDS FOR MID WEEK AND
WILL GET BACK INTO THE 90S FOR MUCH OF THE AREA. HUMIDITY WILL BE
UP TOO...SO IT WILL FEEL UNCOMFORTABLE.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
MODELS IN AGREEMENT BREAKING DOWN MID WEEK UPPER RIDGE ACROSS THE
OHIO VALLEY AND BY THURSDAY IT SHOULD BE MOVING OFF THE MID ATLANTIC
COAST WITH A ZONAL FLOW DROPPING SOUTH ACROSS THE AREA. TO OUR
NORTH AN UPPER LOW WILL BE MOVING ACROSS HUDSON BAY AND THE SURFACE
SYSTEM WILL HAVE A TRAILING COLD FRONT THAT WILL MOVE THROUGH THE
AREA THURSDAY AFTERNOON. GLFMX MOISTURE APPEARS TO BE CLOSED OFF BY
HIGH PRESSURE ACROSS THE SOUTHEASTERN STATES SO SYSTEM SHOULD
HAVE LIMITED MOISTURE. STILL ENOUGH MOISTURE FOR TSTMS TO
ACCOMPANY THE FRONT SO WILL HAVE CHANCE POPS FOR THE AFTERNOON
THURSDAY INTO THURSDAY EVENING. FRIDAY THE FRONT WILL STALL OUT IN
THE LOWER OHIO VALLEY WITH A SURFACE HIGH ACROSS THE AREA. WILL
KEEP FORECAST DRY...SIDING MORE WITH THE ECMWF. SATURDAY MODELS
REDEVELOP AN UPPER RIDGE ACROSS THE NATIONS MID SECTION WITH A
NORTHWEST GRADIENT ALOFT ACROSS OHIO AND THE GREAT LAKES. A WARM
FRONT WILL BE STRENGTHENING ACROSS THE UPPER MIDWEST...AS THE
FRONT WHICH PASSED THROUGH THE AREA THURSDAY BEGINS TO MOVE
NORTHEAST. BOTH MODELS HINTING AT CONVECTION/SHORT WAVE MOVING
INTO THE AREA FROM ACROSS THE GREAT LAKES IN THE NORTHWEST FLOW.
WILL HAVE CHANCE POPS FOR NORTHEAST OHIO AND NORTHWEST PA SATURDAY
AND A SLIGHT CHANCE SUNDAY AS BY THEN THE VERY WARM AIR RETURNS
WITH THE BUILDING UPPER RIDGE.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
NUMEROUS SHOWERS AND THUNDERSTORMS ACROSS NRN OHIO AND NWRN PA
THIS AFTERNOON WILL DECREASE IN COVERAGE THIS EVENING AS DRIER AIR
MOVES IN FROM THE WNW AND UPPER SUPPORT MOVES EAST. EXPECT AN
EVENTUAL CLEAR OUT/BREAK UP IN THE WEST HOWEVER ACROSS THE EAST
ENOUGH LOW LEVEL MOISTURE SHOULD REMAIN IN PLACE OVERNIGHT FOR A
MVFR STRATUS DECK TO DEVELOP ALONG WITH SOME EARLY MORNING FOG.
COULD SEE EARLY MORNING FOG DEVELOPMENT WEST AS WELL. MONDAY
MORNING THIS WILL BURN OFF FOR A VFR DAY OUTSIDE OF ANY LEFTOVER
ISOLATED CONVECTION.
.OUTLOOK...NON VFR POSSIBLE MAINLY IN WIDELY SCT CONVECTION MONDAY
AFTERNOON/EVENING.
&&
.MARINE...
WEAK COLD FRONT WILL MOVE ACROSS THE LAKE THIS EVENING BRINGING
SHOWERS AND THUNDERSTORMS TO THE LAKE. THE FRONT WILL STALL OVER OR
JUST SOUTH OF THE LAKE OVERNIGHT BEFORE RETURNING AS A WARM FRONT
MONDAY. THIS WILL BRING ANOTHER CHANCE OF THUNDERSTORMS TO THE
LAKE. WINDS WILL BE FROM THE SOUTHWEST TONIGHT AT 10 TO 20 KNOTS
AND AGAIN MONDAY BEHIND THE WARM FRONT. TUESDAY THROUGH WEDNESDAY
WINDS WILL DIMINISH TO 10 KNOTS OF LESS MOST PLACES AS HIGH PRESSURE
BUILDS ACROSS THE LAKE FROM THE EAST. ANOTHER COLD FRONT WILL MOVE
ACROSS THE LAKE FROM THE NORTHWEST THURSDAY AND WILL BRING ANOTHER
CHANCE OF THUNDERSTORMS. WAVES WILL REMAIN BELOW 4 FEET THROUGH THE
PERIOD.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...OUDEMAN
NEAR TERM...OUDEMAN
SHORT TERM...OUDEMAN
LONG TERM...TK
AVIATION...TK
MARINE...TK
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
521 PM EDT SUN JUN 17 2012
.SYNOPSIS...
A FRONTAL BOUNDARY PUSHING EASTWARD THROUGH THE UPPER OHIO VALLEY
WILL BRING A LINE OF SHOWERS AND THUNDERSTORMS TOWARD THE WESTERN
ALLEGHENIES THIS EVENING. SHOWERS WILL ACCOMPANY THE FRONTAL ZONE AS
IT SHIFTS EASTWARD ACROSS THE CENTRAL MOUNTAINS LATER TONIGHT INTO
EARLY MONDAY. A MOIST SOUTHERLY FLOW SHOULD WILL BRING PLENTY OF
CLOUDS TO THE AREA ON MONDAY. A STRONG UPPER LEVEL RIDGE WILL
BUILD OVER THE MID-ATLANTIC STATES THROUGH MID-WEEK...BRINGING
HOT AND HUMID CONDITIONS TO THE COMMONWEALTH. THE HOT RIDGE WILL
BREAKDOWN BY THE END OF THE WORK WEEK...WITH MORE SEASONAL
TEMPERATURES EXPECTED IN THE WAKE OF A COLD FRONT FRIDAY INTO THE
UPCOMING WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
AN AXIS OF SHOWERS AND THUNDERSTORMS CURRENTLY DEVELOPING FM
CENTRAL OH SWD INTO KY IS FCST TO MOVE INTO WRN PA THIS EVE. MESO
MDL DATA KEEPS THE BULK OF THE CONVECTION WEST OF THE ALLEGHENIES
PRIOR TO 00Z. WITH THE LOSS OF DAYTIME HEATING AND LOWER DEWPOINTS
FURTHER TO THE EAST...TSTMS SHOULD WEAKEN IN INTENSITY AS THEY
APPROACH THE LAURELS AND NW MTNS BTWN 00-03Z. A STRIPE OF 850MB
THETA-E ADVECTION AND CONVERGENCE ALONG THE EWD SHIFTING MOIST
AXIS WILL DRIVE SHOWERS INTO THE CNTRL MTNS LATE TNT INTO EARLY
MONDAY. THE BEST INSTABILITY REMAINS ALONG/WEST OF THE ALLEGHENIES
SO CUT BACK THUNDER MENTION TO SCHC. DESPITE HIGH PWATS...MID-
UPPER FORCING IS STILL WEAK SO QPF AMTS WILL BE MAINLY LIGHT.
INCREASING LOW LEVEL MSTR/SFC DEWPOINTS VIA SLY FLOW SHOULD BRING
LOW CLOUDS INTO THE AREA OVERNIGHT AND KEEP MINS AOA GUIDANCE
ESPECIALLY OVER THE WESTERN 1/2 OF THE CWA.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
HI PWAT AXIS ASSOCD WITH DISSIPATING FRONT/850MB LLVL CONVERGENCE
AXIS WILL SHIFT EWD EARLY MONDAY WITH SHOWERS LKLY MOVG INTO THE
SUSQ VLY. MDL DATA SUGGESTS LOW CLOUDS WILL BE DIFFICULT TO
ERODE THRU THE DAY GIVEN HI DEWPTS AND CONTINUED MOIST SLY LLVL
FLOW. H5 HEIGHTS WILL INCREASE THRU THE PD AS SUMMERTIME RIDGE
BEGINS TO BUILD INTO THE OH VLY. WITH RATHER WEAK FORCING ALOFT
AND LIMITED INSTABILITY DUE TO PERSISTENT CLOUD COVER...SHOWER
CVRG SHOULD BECOME ISOLD-SCT AT BEST AND HAVE DROPPED POPS BACK TO
20-30 PCT FROM TOMORROW AFTN THRU TOMORROW NIGHT. MAV/MET/ECM
BLEND SUGGESTS HIGHS MAY STRUGGLE TO GET MUCH ABOVE 70F E OF THE
MTNS...WHERE WEAK UPSLOPE SHOULD HELP TO KEEP LOW CLOUDS IN PLACE.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
BY TUESDAY...STRONG RIDGE AXIS WILL BE BUILDING ACROSS NORTHEAST
U.S. WITH CENTER OF HIGH OVER OHIO VALLEY. WITH BROAD SW FLOW IN
LOW LEVELS...TUESDAYS TEMPS WILL BE WELL ABOVE NORMAL ACROSS THE
WEST...AND NOT QUITE AT HOT IN THE EAST.
HEIGHTS ALOFT CONTINUE TO BUILD THROUGH WED...BRINGING THE HOTTEST
DAY OF THE WEEK. SFC TEMPS SURGE INTO THE UPPER 80S TO LOWER 90S
AREAWIDE AS MID LEVEL TEMPS BETWEEN 8-10C WITH +18-20C AT 850MB
WILL SUPPRESS CHANCE OF CONVECTION.
THU WILL REMAIN HOT FOR MOST...POSS EVEN HOTTER THAN WED IN THE
SUSQ VALLEY /WHERE MID 90S ARE LIKELY/. INCREASING CLOUDS AND
SLIGHTLY COOLER AIR ALOFT WILL KEEP NW MTNS IN THE MID 80S...WHICH
IS STILL WELL ABOVE NORMAL.
MODELS ARE IN GENERAL AGREEMENT IN A COOL DOWN TOWARD THE END OF
THE WEEK AS OUR UPPER RIDGE TRANSITIONS TO AN UPPER TROF. THIS
WILL BRING CHANCES FOR RAIN AS SHORTWAVES RIPPLE DOWN THRU THE
FLOW INTO THE NORTHEAST STARTING FRIDAY. TIMING AT THIS RANGE IS
TOUGH...AND HEDGED LOW POPS TOWARD DAYTIME DIURNAL MAX PERIODS.
&&
.AVIATION /21Z SUNDAY THROUGH FRIDAY/...
LINE OF SHRA/TSRA ASSOCIATED WITH APPROACHING TROF OF LOW PRESSURE
WILL LIKELY WEAKEN AS IT MOVES INTO THE WRN AIRFIELDS BTWN 02-04Z
BASED ON LATEST HRRR AND NAMPARA MDL DATA. EXPECT FURTHER
WEAKENING OVERNIGHT WITH REMNANT SHOWERS PUSHING INTO THE EASTERN
HALF OF PA AFTER MIDNIGHT. SHOWERS SHOULD MAINLY BE CONFINED TO
ERN SXNS EARLY MONDAY. XPECT CIGS TO LOWER INTO MVFR CATG
OVERNIGHT THRU EARLY MONDAY. A PERIOD OF IFR CIGS ARE ALSO
POSSIBLE PER TABULAR GUID. MDL DATA SUGGESTS LOW CIGS SHOULD
PERSIST THRU AT LEAST THE FIRST HALF OF THE DAY ON MONDAY WITH HI
LLVL MSTR AND SLY FLOW PATTERN REMAINING IN PLACE. SOME MARGINAL
IMPROVEMENT IS ANTICIPATED BY LATER MON AFTN. THE MID- WEEK PERIOD
LOOKS MAINLY DRY AS UPPER LEVEL RIDGE BUILDS OVER THE AREA. MAIN
IMPACTS TO AVN DURING THIS TIME WILL BE LOW CLOUDS/FOG/HZ DURING
THE PREDAWN/EARLY MORNING HOURS.
OUTLOOK...
TUE-WED...AM FOG-HZ/LOW CIGS POSSIBLE...OTHERWISE VFR.
THUR...AM FOG-HZ/LOW CIGS POSSIBLE. ISOLD PM TSTM IMPACTS WRN AREAS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...RXR
AVIATION...FITZGERALD/STEINBUGL
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
222 PM CDT SUN JUN 17 2012
.SYNOPSIS...POTENTIALLY VERY ACTIVE WEATHER THE NEXT FEW DAYS.
VERY BROAD/FLAT UPR TROF CURRENTLY EXTENDING FM THE ERN PAC TO
THE WRN GREAT LAKES RGN WL UNDERGO AMPLIFICATION EARLY IN THE FCST
PERIOD AS THE TROF AXIS CONSOLIDATES OVER THE NRN ROCKIES. THEN
PATTERN WL UNDERGO READJUSTMENT DURING THE WEEK...SO THAT BY NEXT
WEEKEND THERE SHOULD BE A SPRAWLING UPR HIGH OVER THE CENTRAL
PLAINS WITH RIDGING EXTENDING NWD ACRS THE NRN PLAINS/PRAIRIE
PROVINCES OF CANADA...AND WITH UPR TROFS ALONG BOTH COASTS.
WANT TO BE CAREFUL ABOUT FCSTG TOO MUCH PCPN GIVEN THE RECENT DRY
WX...BUT PROGGED PATTEN CERTAINLY SEEMS FAVORABLE FOR ABV NORMAL
PCPN AMNTS. TEMPS WL START OUT WELL ABV NORMAL...THEN TREND BACK
CLOSER TO...BUT STILL SOMEWHAT ABV...SEASONAL NORMALS.
&&
.SHORT TERM...TONIGHT AND MONDAY.
LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW LAST NIGHTS
COLD FRONT STRETCHING FROM LAKE HURON TO NORTHERN MISSOURI EARLY
THIS AFTERNOON WHILE BROAD LOW PRESSURE EXISTS OVER THE DAKOTAS.
ELEVATED SHOWERS AND THUNDERSTORMS ARE MOVING OVER SOUTHEAST
MINNESOTA ALONG THE 850MB THETA-E GRADIENT. ADDED SMALL POPS OVER
THE WESTERN CWA AFTER 21Z IN CASE THEY MAKE IT. OTHERWISE...AN
ENERGETIC JET STREAK IS PUSHING A SHORTWAVE INTO NORTH DAKOTA.
CONVECTION IS EXPECTED TO DEVELOP OVER THE ND/SD BORDER AHEAD OF
THIS SHORTWAVE AND THE BROAD SURFACE LOW LATER THIS AFTERNOON. THE
MAIN FORECAST CONCERN IS SEVERE WEATHER CHANCES AS THIS CONVECTION
ORGANIZES LATER TODAY AND MOVES EAST INTO THE REGION.
TONIGHT...THE CHALLENGING FORECAST STARTS OUT RIGHT OFF THE BAT
THIS EVENING AND ONLY BECOMES MORE COMPLEX THROUGH MONDAY. SHOWERS
AND THUNDERSTORMS OVER SOUTHEAST MINNESOTA WILL CONTINUE TO TRACK
EAST THIS AFTERNOON ALONG THE 850MB THETAE GRADIENT/MID-LEVEL
RETURN FLOW. THIS RETURN FLOW IS EXPECTED TO BACK TO THE SOUTH
THIS AFTERNOON AHEAD OF SHORTWAVE ENERGY MOVING INTO NORTH DAKOTA.
AS A RESULT...AM EXPECTING THIS AREA OF SHOWERS AND STORMS TO
WEAKEN BEFORE THEY MOVE INTO CENTRAL WISCONSIN. HOWEVER...THAT
850MB THETA-E GRADIENT DOES PUSH INTO CENTRAL WISCONSIN THIS
EVENING AND DO NOT ENTIRELY TRUST THAT EVERYTHING WILL HAVE
DISSIPATED BY 00Z. ADDED CHANCE POPS OVER THE WESTERN CWA TO
ACCOUNT FOR THIS. OTHERWISE...THINKING AT THIS TIME THAT THE MAIN
SHOW FOR TONIGHT WILL GET GOING LATER THIS AFTERNOON ALONG A WARM
FRONT POSITIONED OVER THE EASTERN ND/SD BORDER INTO CENTRAL
MINNESOTA. THIS CONVECTION SHOULD BECOME INCREASINGLY ELEVATED
THIS EVENING AS SURFACE BASED INSTABILITY IS LOST AND A 40-50KT
LLJ DEVELOPS. TRACKING THIS MCS IS TRICKY DUE TO MASS CONVERGENCE
ALONG THE NOSE OF THE LLJ MOVING NORTHEAST...WHILE INSTABILITY
REMAINS TO THE SOUTH ON THE EDGE OF THE CAP (MID-LEVEL LAPSE RATE
GRADIENT). A ROUGH GUESS WOULD TRACK THE MCS TO THE ENE ON THE
NOSE OF THE LLJ...WHILE THE STRONGEST THUNDERSTORMS MOVE EAST OR
ESE TOWARDS THE INSTABILITY. ELEVATED CAPES OF 1000-1400 J/KG AT
09Z SUGGEST THAT THUNDERSTORMS WILL HAVE POTENTIAL TO SUSTAIN
THEMSELVES AS THEY MOVE INTO N-C AND CENTRAL WISCONSIN AFTER
MIDNIGHT. FREEZING LEVELS ARE HIGH (15KFT)...SO THINK THE MAIN
THREATS WILL BE STRONG GUSTY WINDS DUE TO THE BEEFY LLJ OVERHEAD
AND HEAVY RAINFALL (PWATS 1.7 INCHES AND K-INDEX OF 41). THE MCS
SHOULD GRADUALLY WEAKEN AS IT MOVES INTO NE WISCONSIN LATE
TONIGHT.
MONDAY...THE MCS SHOULD MOVE ACROSS NORTHEAST WISCONSIN BEFORE
EXITING DURING THE MORNING. ANTICIPATE PLENTY OF CLOUD COVER LEFT
OVER FROM THE MCS WHICH SHOULD HOLD BACK TEMPS IN THE MORNING.
VERY WARM TEMPS AT 850MB AND THE HIGH SUN ANGLE SHOULD PARTIALLY
ERODE CLOUD COVER IN THE AFTERNOON. THE AMOUNT OF HEATING WE
RECEIVE WILL LARGELY DETERMINE THUNDERSTORM POTENTIAL DURING THE
PM HOURS. WILL HAVE A COOL FRONT PUSH INTO N-C WISCONSIN LATE IN
THE AFTERNOON...AND POSSIBLE OUTFLOW BOUNDARIES/DIFFERENTIAL
HEATING BOUNDARIES TO SERVE AS A FOCUS FOR CONVECTION. THINK THE
BEST CHANCES OF THUNDERSTORMS WILL BE OVER CENTRAL WISCONSIN AND
THE FOX VALLEY WHERE TEMPS COULD REACH INTO THE UPPER 80S. THE NAM
SUGGESTS THIS POSSIBILITY AS WELL...THOUGH ITS NOT CLEAR IF
CONVECTION CONTINUES ON THE TAIL OF THE MCS...OR REDEVELOPS ON
OTHER BOUNDARIES. 0-6KM BULK SHEAR VALUES OF 40-60KTS AND ML CAPES
OF 1500 J/KG SUGGEST SEVERE WEATHER IS POSSIBLE IF CONVECTION DOES
DEVELOP AND MAIN THREATS SHOULD BE STRONG GUSTY WINDS AND LARGE
HAIL. CONVECTION IS MORE UNCERTAIN ALONG THE COLD FRONT DUE TO
CLOUD COVER CONCERNS. WILL GO WITH HIGHS AROUND 80F NORTH TO UPPER
80S SOUTH.
.LONG TERM...MON NGT THROUGH NEXT SUN. THE FLOW WITHIN THE BASE
OF THE BROAD UPR TROF ACRS THE NWRN PART OF THE CONUS WAS PRETTY
STG FOR JUNE...WITH UPR SPEED MAX OF NEARLY 150 KTS WORKING EWD
ACRS THE PAC NW. THE JET WORKING E COMBINED WITH THE AMPLIFICATION
OF THE LARGE SCALE PATTERN CERTAINLY HAS THE POTENTIAL TO RESULT
IN VERY ACTIVE WX ACRS THE FCST AREA...AS FRONTAL BOUNDARY
OSCILLATES N AND S FOR A COUPLE DAYS. SEVERAL ROUNDS OF SVR
CONVECTION ARE LIKELY IN THE UPPER MIDWEST/GREAT LAKES RGN...WITH
QUESTION BEING WHETHER/WHEN INDIVIDUAL EVENTS AFFECT THE FCST
AREA. TRIED TO ADD A LITTLE RESOLUTION TO POPS...BUT WITH PCPN
CHCS GENERALLY TIED TO POSN OF FRONT AND THAT DEPENDING ON PRIOR
MCS DEVELOPMENT/MVMT...THERE WAS NO WAY TO REALLY GET ARND HAVING
SEVERAL PERIODS WITH HIGHER END CHC POPS AT LEAST SOMEWHERE IN THE
AREA.
ONCE THE MAJOR SHRTWV EJECTING OUT OF THE WRN TROF CROSSES THE RGN
MID-WEEK...A COUPLE DAYS OF QUIETER WEATHER ARE POSSIBLE DURING
THE LATTER PART OF THE WEEK. BUT IT WL BE HARD TO TOTALLY RULE OUT
PCPN AS FCST AREA BECOMES POSITIONED ALONG THE SRN EDGE OF THE
WESTERLIES...AND IN A LCN SUSCEPTIBLE TO CONVECTION FIRING ARND
THE PERIPHERY OF THE DEVELOPING PLAINS UPR HIGH.
&&
.AVIATION...SHOWERS AND STORMS OVER MINNESOTA ARE EXPECTED TO
WEAKEN THIS AFTERNOON BEFORE THEY MOVE INTO CENTRAL WISCONSIN.
HOWEVER...A LARGE COMPLEX OF THUNDERSTORMS IS ANTICIPATED TO
DEVELOP OVER MINNESOTA THIS AFTERNOON AND EVENING. UNCERTAINTY
EXISTS HOW FAR SOUTH THEY WILL MOVE...BUT AT THIS TIME...IT
APPEARS RHI/CWA/AUW WILL SEE THUNDERSTORMS ARRIVE AFTER MIDNIGHT.
THESE THUNDERSTORMS WILL HAVE POTENTIAL TO CREATE STRONG GUSTY
WINDS AND LARGE HAIL. THINK STORMS WILL MAKE IT INTO GRB/ATW LATE
TONIGHT INTO TOMORROW MORNING. THEREAFTER...SOME STRONG STORMS MAY
REDEVELOP TOMORROW AFTERNOON ASSUMING BREAKS IN THE CLOUDS WILL
ALLOW TEMPERATURES TO WARM ENOUGH. THE BEST CHANCES WILL BE AT GRB
AND ATW.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MPC/SKOWRONSKI
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1244 PM CDT SUN JUN 17 2012
.SHORT TERM...THIS AFTERNOON
1124 AM CDT SUN JUN 17 2012
THE LATEST WATER VAPOR IMAGERY SHOWS A SHORT WAVE MOVING THROUGH
EASTERN SOUTH DAKOTA. BOTH THE 17.12Z NAM/WRF AND GFS SUGGEST THAT
THIS WAVE WILL MOVE EAST THROUGH THE NORTHERN HALF OF OUR FORECAST
AREA LATE THIS AFTERNOON AND EVENING. SHOWERS AND THUNDERSTORMS
ARE DEVELOPING AT THE NOSE OF MODERATE TO STRONG 925 MB AND 850 MB
MOISTURE TRANSPORT IN THE ADVANCE OF THE SHORT WAVE. THIS MOISTURE
TRANSPORT WILL MOVE EAST THIS AFTERNOON AND WILL LIKELY AFFECT
SOUTHEAST MINNESOTA. FURTHER EAST...THERE IS SOME QUESTION ON
WHETHER IT WILL ADVANCE INTO WEST-CENTRAL AND NORTH-CENTRAL
WISCONSIN. THE 17.12Z HRRR SHOWED THAT THE SHOWERS AND
THUNDERSTORMS WOULD MOVE INTO SOUTHEAST MINNESOTA AFTER 1 PM AND
MAY MOVE INTO WEST-CENTRAL AND NORTH-CENTRAL WISCONSIN AFTER 4 PM.
DUE TO THIS...THE FORECAST WAS TRENDED TOWARD HIGH PRECIPITATION
CHANCES.
.LONG TERM...WEDNESDAY THROUGH SATURDAY
425 AM CDT SUN JUN 17 2012
THIS PERIOD BEGINS WITH RAIN AND A FRONTAL PASSAGE...AND THEN FOR
THE MOST PART IS A COOLER AND DRY PERIOD. THE WAVERING FRONT
WHICH DOMINATED THE SHORT TERM WILL STALL PARALLEL TO THE UPPER
FLOW ACROSS MN...UNTIL WEDNESDAY WHEN IT SAGS THROUGH THE AREA
WITH ANOTHER GOOD RAIN AND SEVERE WEATHER CHANCE FOR MOST AREAS.
DEPENDING ON HOW MUCH RAIN WE HAVE SEEN AT THAT POINT...THE SLOW
MOVING FRONT MAY CAUSE LOCALIZED FLOODING WITH HIGHER RUNOFF SEEN.
DEEP SHEAR WILL STILL BE IN PLACE AND DEPENDING ON TIMING..INSTABILITY
MAY BE BOUNTIFUL.
THE FRONT WILL SAG SOUTH PROVIDING DRY WEATHER THROUGH ABOUT
FRIDAY NIGHT WHEN IT RETURNS AS A WARM FRONT...AND CONVECTIVE
CHANCES RETURN. TEMPERATURES WILL BE AT OR BELOW NORMAL FOR THE
THU-SAT PERIOD.
&&
.AVIATION...THROUGH 18Z MONDAY
1243 PM CDT SUN JUN 17 2012
A SHORT WAVE TROUGH WILL MOVE EAST ACROSS THE FORECAST AREA THIS
AFTERNOON AND EARLY EVENING. SHOWERS AND THUNDERSTORMS HAVE
ALREADY DEVELOPED ACROSS SOUTHERN MINNESOTA WEST OF INTERSTATE 35...
AND THEY WILL MOVE THROUGH KRST BETWEEN 17.1930Z AND 17.2330Z...
AND MAY MOVE THROUGH KLSE BETWEEN 17.21Z AND 18.01Z.
ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS WILL LIKELY DEVELOP
ACROSS WEST-CENTRAL MINNESOTA LATE THIS AFTERNOON AND EVENING
AHEAD OF ANOTHER SHORTWAVE TROUGH. THIS SYSTEM WILL THEN MOVE
EAST-SOUTHEAST THROUGH EAST-CENTRAL MINNESOTA AND CENTRAL
WISCONSIN OVERNIGHT. AT CURRENT TIME...THINKING THAT THESE STORMS WILL
REMAIN NORTH OF BOTH TAF SITES...SO THEY WERE NOT INCLUDED IN THE
TAF FORECAST.
AS DIURNAL HEATING OCCURS ON MONDAY MORNING...THE SOUTH WINDS
WILL BEGIN TO GUST INTO THE 20 TO 25 KNOT RANGE.
&&
.HYDROLOGY...
425 PM CDT SUN JUN 17 2012
THE AREA WILL SEE PERIODIC HEAVY RAIN OPPORTUNITIES FROM MONDAY TO
WEDNESDAY. HOWEVER...IT IS STARTING TO APPEAR AS THOUGH NO ONE
AREA MAY BE FAVORED FOR MULTIPLE HEAVY RAINFALL EVENTS. MOST AREAS
SHOULD SEE PRECIPITATION THROUGH WEDNESDAY AND SOME AREAS COULD
END UP WITH MULTIPLE INCHES. THE SYSTEMS SHOULD ALSO BE
MOVING...WHICH WILL LIMIT EXTREME RAINFALL IT APPEARS.
THEREFORE...IT SEEMS RIVER RISES WILL OCCUR OVER THE AREA IN THE
NEXT WEEK WITH NO PREFERENCE TO ANY GIVEN RIVER. LOCALIZED
FLASH FLOODING MAY STILL BE POSSIBLE AS THE RAINFALL RATES WITH
THE THUNDERSTORM SYSTEMS COULD BE QUITE HIGH.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
425 AM CDT SUN JUN 17 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM....BAUMGARDT
AVIATION...BOYNE
HYDROLOGY....BAUMGARDT
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1125 AM CDT SUN JUN 17 2012
.SHORT TERM...THIS AFTERNOON
1124 AM CDT SUN JUN 17 2012
THE LATEST WATER VAPOR IMAGERY SHOWS A SHORT WAVE MOVING THROUGH
EASTERN SOUTH DAKOTA. BOTH THE 17.12Z NAM/WRF AND GFS SUGGEST THAT
THIS WAVE WILL MOVE EAST THROUGH THE NORTHERN HALF OF OUR FORECAST
AREA LATE THIS AFTERNOON AND EVENING. SHOWERS AND THUNDERSTORMS
ARE DEVELOPING AT THE NOSE OF MODERATE TO STRONG 925 MB AND 850 MB
MOISTURE TRANSPORT IN THE ADVANCE OF THE SHORT WAVE. THIS MOISTURE
TRANSPORT WILL MOVE EAST THIS AFTERNOON AND WILL LIKELY AFFECT
SOUTHEAST MINNESOTA. FURTHER EAST...THERE IS SOME QUESTION ON
WHETHER IT WILL ADVANCE INTO WEST-CENTRAL AND NORTH-CENTRAL
WISCONSIN. THE 17.12Z HRRR SHOWED THAT THE SHOWERS AND
THUNDERSTORMS WOULD MOVE INTO SOUTHEAST MINNESOTA AFTER 1 PM AND
MAY MOVE INTO WEST-CENTRAL AND NORTH-CENTRAL WISCONSIN AFTER 4 PM.
DUE TO THIS...THE FORECAST WAS TRENDED TOWARD HIGH PRECIPITATION
CHANCES.
.LONG TERM...WEDNESDAY THROUGH SATURDAY
425 AM CDT SUN JUN 17 2012
THIS PERIOD BEGINS WITH RAIN AND A FRONTAL PASSAGE...AND THEN FOR
THE MOST PART IS A COOLER AND DRY PERIOD. THE WAVERING FRONT
WHICH DOMINATED THE SHORT TERM WILL STALL PARALLEL TO THE UPPER
FLOW ACROSS MN...UNTIL WEDNESDAY WHEN IT SAGS THROUGH THE AREA
WITH ANOTHER GOOD RAIN AND SEVERE WEATHER CHANCE FOR MOST AREAS.
DEPENDING ON HOW MUCH RAIN WE HAVE SEEN AT THAT POINT...THE SLOW
MOVING FRONT MAY CAUSE LOCALIZED FLOODING WITH HIGHER RUNOFF SEEN.
DEEP SHEAR WILL STILL BE IN PLACE AND DEPENDING ON TIMING..INSTABILITY
MAY BE BOUNTIFUL.
THE FRONT WILL SAG SOUTH PROVIDING DRY WEATHER THROUGH ABOUT
FRIDAY NIGHT WHEN IT RETURNS AS A WARM FRONT...AND CONVECTIVE
CHANCES RETURN. TEMPERATURES WILL BE AT OR BELOW NORMAL FOR THE
THU-SAT PERIOD.
&&
.AVIATION...TODAY AND TONIGHT
623 AM CDT SUN JUN 17 2012
QUIET/DRIER HIGH PRESSURE WILL DRIFT ACROSS THE AREA TODAY WITH GOOD
VFR CONDITIONS AND LIGHT WINDS ON THIS FATHERS DAY. MOISTURE/
INSTABILITY WILL SURGE BACK INTO THE AREA TONIGHT...AHEAD OF LOW
PRESSURE MOVING INTO MN. A COMPLEX OF STRONG TO SEVERE STORMS IS
EXPECTED TO DEVELOP IN EASTERN SD TO FAR WESTERN MN LATE THIS
AFTERNOON/EARLY THIS EVENING...THEN MOVE EAST/SOUTHEAST INTO
SOUTHEAST MN/WESTERN WI DURING THE LATE EVENING INTO OVERNIGHT
HOURS. GIVEN CONSIDERABLE VARIABILITY IN POTENTIAL TIMING/OUTCOMES
FOR THE CONVECTION TONIGHT...ONLY INCLUDED MVFR CIGS/VSBYS WITH
SHRA/VCTS/CB IN THE 05-09Z TIME-FRAME FOR NOW. ONCE THE COMPLEX
BEGINS TO EVOLVE...LATE SHIFTS/TAF UPDATES CAN FINE TUNE THE
EXPECTED TIMING/CONDITIONS...INCLUDING ADDING A WESTERLY WIND GUST
GROUP...FOR ITS ARRIVAL AND PASSAGE. CONDITIONS SHOULD THEN RETURN
TO VFR FOR LATE TONIGHT/MON MORNING AS THE COMPLEX MOVE INTO EASTERN
WI AND SUBSIDENCE IN ITS WAKE SPREADS ACROSS THE AREA.
&&
.HYDROLOGY...
425 PM CDT SUN JUN 17 2012
THE AREA WILL SEE PERIODIC HEAVY RAIN OPPORTUNITIES FROM MONDAY TO
WEDNESDAY. HOWEVER...IT IS STARTING TO APPEAR AS THOUGH NO ONE
AREA MAY BE FAVORED FOR MULTIPLE HEAVY RAINFALL EVENTS. MOST AREAS
SHOULD SEE PRECIPITATION THROUGH WEDNESDAY AND SOME AREAS COULD
END UP WITH MULTIPLE INCHES. THE SYSTEMS SHOULD ALSO BE
MOVING...WHICH WILL LIMIT EXTREME RAINFALL IT APPEARS.
THEREFORE...IT SEEMS RIVER RISES WILL OCCUR OVER THE AREA IN THE
NEXT WEEK WITH NO PREFERENCE TO ANY GIVEN RIVER. LOCALIZED
FLASH FLOODING MAY STILL BE POSSIBLE AS THE RAINFALL RATES WITH
THE THUNDERSTORM SYSTEMS COULD BE QUITE HIGH.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
425 AM CDT SUN JUN 17 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM....BAUMGARDT
AVIATION.....RRS
HYDROLOGY....BAUMGARDT