Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/15/12
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
940 AM MDT WED JUN 13 2012
.UPDATE...NO CHANGES TO THE GRIDS AT THIS TIME. THE LATEST NAM12
FCST SOUNDINGS DOES INDICATE SOME MINIMAL CAPE AROUND 200 J/KG
THIS AFTN. NOT ENOUGH FOR TSTMS BUT BY ENOUGH TO PRODUCE SOME WEAK
CB BUILDUPS AND BRIEF GUSTY OUTFLOW WINDS. THE 12Z HRRR DEVELOPS
MINIMAL CELL COVERAGE AS WELL THIS AFTN WITH THE ACTIVITY EAST OF
THE DENVER AREA. OVERALL HOT AND DRY THE GOING THEME. WINDS AT THE
HIGH PARK WILDFIRE MAY BE SIMILAR TO YESTERDAY WITH W-SWLY WINDS
ON THE WEST SIDE...WITH MORE OF AN E-SELY COMPONENT ON THE EAST
SIDE. THE WINDS OVER THE BURN AREA MAY BECOME W-SWLY ON THE EAST
SIDE IN THE AFTN...AFTER 20Z. IN SPITE OF THE HOT AND DRY
CONDITIONS...WILL HOLD OFF ON ISSUING ANY FIRE WEATHER HIGHLIGHT
DUE TO THE LACK OF A STRONG SFC WIND COMPONENT.
&&
.AVIATION...VFR CONDITIONS OVER THE NEXT 24 HRS. THE MDLS DO HINT
AT SOME CELL DEVELOPMENT THIS AFTN...BUT WEAK AND EAST OF THE
DENVER AREA. SOME WEAK CB BUILDUPS NEAR D.I.A. COULD PRODUCE BRIEF
GUSTY OUTFLOW WINDS TO 25 KTS...BUT NOT ENOUGH CONFIDENCE TO ADD
IT TO THE TAF. A DRY COLD FRONT IS STILL PROGGED TO PUSH THROUGH
THE DENVER AREA OVERNIGHT...COULD BE SOONER...IN THE 09-12Z TIME
FRAME SO MAY ADJUST THE TIMING IN THE 18Z TAF ISSUANCE. ESELY
WINDS PROGGED THE LOW LEVEL MOISTURE ADVECTING INTO THE DENVER
AREA THROUGH THE DAY WEDNESDAY...SO THE PROSPECTS OF THUNDERSTORMS
BETTER IN THE AFTN SO WL ADD VCTS TO THE OUTLOOK PERIOD FOR D.I.A.
&&
.PREV DISCUSSION... /ISSUED 259 AM MDT WED JUN 13 2012/
SHORT TERM...THERE IS A CONTINUED MODERATE WESTERLY FLOW ALOFT
ACROSS COLORADO TODAY...WHICH WILL BE GRADUALLY SHIFTING MORE
SOUTHWESTERLY LATER TODAY AND TONIGHT. THE AIRMASS CONTINUES ON A
DRYING AND WARMING TREND. 700MB TEMPS RISE TO AROUND +16C AT
DENVER AND THIS WILL RESULT IN ANOTHER 4-6 DEGREES OF WARMING
TODAY. END RESULT WILL BE TEMPERATURES WELL INTO THE 90S ACROSS
LOWER ELEVATIONS. THE RECORD FOR DENVER TODAY IS 99 SO SHOULD BE
WELL SHORT OF THAT. FORECAST SOUNDINGS SHOW SOME MIDDLE LEVEL
MOISTURE BY LATER IN THE DAY BUT EXTREMELY DRY LOW LEVELS SHOULD
RESULT IN NO STORMS TODAY. THE ONLY EXCEPTION WOULD BE OVER THE
FAR EASTERN PLAINS OVER LINCOLN COUNTY TOWARDS EVENING WHERE LOW
LEVEL MOISTURE WOULD BE A BIT HIGHER. NOT EVEN THRILLED WITH
CHANCES OUT THERE BUT WILL LEAVE IN AN EVER SO SLIGHT CHANCE. IN
TERMS OF FIRE WEATHER CONCERNS IT WILL CERTAINLY BE WARM WITH LOW
HUMIDITIES 10-15 PERCENT BUT WIND GUSTS WILL GENERALLY BE BELOW
THRESHOLD NEEDED FOR ANY FIRE WEATHER HILITES. A FEW GUSTS IN THE
15-25 MPH RANGE CERTAINLY BUT NOT SUSTAINED AND WIDESPREAD ENOUGH
TO WARRANT ANY BIG FIRE CONCERNS. WIND SPEEDS SHOULD BE SIMILAR TO
YESTERDAY OVER MOUNTAINS AND FOOTHILLS.
LONG TERM...THURSDAY STARTS OUT WITH THE HIGH PLAINS CAPPED BY A
SHALLOW FRONTAL INVERSION WHICH IS TOPPED BY A WARM AND DRY
WESTERLY FLOW ASSOCIATED WITH A PASSING MID-LEVEL SHORTWAVE RIDGE.
LIGHT POST-FRONTAL EAST-NORTHEASTERLY WINDS ON THE PLAINS ARE
PROGGED TO TURN SOUTHEASTERLY LATE IN THE DAY WHICH ADVECTS
INCREASING AMOUNTS OF LOW-LEVEL MOISTURE UP AGAINST THE FRONT
RANGE DURING THE EVENING HOURS. THE RESULTANT DESTABILIZATION MAY
CAUSE A FEW GUSTY SHOWERS/T-STORMS TO FORM OVER AND NEAR THE FRONT
RANGE DURING THE EVENING. UNFORTUNATELY DO NOT SEE MUCH IN THE WAY
OF WETTING RAINFALL FROM THIS HIGH BASED CONVECTION. SO LIGHTNING
MAY POSE A THREAT FOR NEW FIRE IGNITIONS WHERE FUELS REMAIN QUITE
DRY. OVERNIGHT...MODELS SHOW LOW-LEVEL MOISTURE CONTINUING TO
FLOW INTO THE AREA ON SOUTHEASTERLY BOUNDARY LAYER WINDS...
POSSIBLY RESULTING IN POCKETS OF FOG TOWARDS MORNING.
ON FRIDAY...PATCHY FOG ON THE PLAINS IS EXPECTED TO BURN OFF BY
MID-MORNING WITH STRONG SOLAR HEATING. MODELS THEN SHOW A WEAK
SHORTWAVE TROUGH OVER THE 4-CORNERS AREA PASSING OVER THE
FORECAST AREA LATE IN THE DAY. COULD SEE CONVECTION BEGINNING IN
THE HIGH COUNTRY...NOT LONG AFTER MIDDAY WITH THE APPROACHING
SHORTWAVE. HOWEVER STORM COVERAGE IN THE HIGH COUNTRY PROBABLY NO
MORE THAN ISOLATED IN COVERAGE DUE TO A LACK OF MID-LEVEL
MOISTURE. AS THE LIFT GENERATED BY THIS WAVE INTERACTS WITH THE
RELATIVELY MOIST AND UNSTABLE AIR MASS ON THE PLAINS...COULD SEE
ISOLATED TO SCATTERED T-STORMS DEVELOPING DURING THE LATE
AFTERNOON AND EVENING HOURS. DOES NOT LOOK FAVORABLE FOR SEVERE
WEATHER...BUT CAN/T RULE OUT AN ISOLATED SEVERE STORM WITH
MOISTURE AROUND THIS TIME OF YEAR. LATER THAT NIGHT MAY SEE
PATCHING FOG FORMING AGAIN ON THE PLAINS ACCORDING TO THE NAM.
ON SATURDAY...MODELS SHOW THE DEEP UPPER LOW/TROUGH OVER THE
DESERT SOUTHWEST RETROGRADING WHICH ALLOWS A SECONDARY TROUGH TO
DROP SOUTH OUT OF IDAHO AND WESTERN WYOMING. MODELS SHOW THE
LEADING EDGE OF SLIGHTLY COOLER AND MORE MOIST AIR MASS SLIPPING
INTO NORTHEAST COLORADO DURING THE MORNING. THIS PUSH LOOKS
STRONGEST ON THE NAM. AS THE UPPER TROUGH SWINGS EAST ACROSS
WYOMING AND NORTHERN COLORADO DURING THE DAY...QG VERTICAL
VELOCITY FIELDS INDICATE WEAK UPPER MOTION OVER NORTHEAST COLORADO
DURING THE AFTERNOON AND EVENING HOURS. MODELS ALSO INDICATE
AREAS OF LIGHT QPF. THERE IS A SLIGHT CHANCE WE COULD SEE A
SEVERE STORM OR TWO ALONG A FRONTAL BOUNDARY WHICH THE NAM AND
CANADIAN GEM SHOW STRADDLED ACROSS THE NORTHEAST CORNER OF
COLORADO AROUND 00Z/SUN. CURRENT FORECAST GRIDS INDICATE 20-30
PERCENT POPS ACROSS THE AREA SATURDAY AFTERNOON AND EVENING. SEE
LITTLE REASON TO CHANGE THEM AT THIS TIME.
SUNDAY-TUESDAY...WITH THE UPPER TROUGH PASSING OVERHEAD SATURDAY
NIGHT...FLOW BOTH SFC AND ALOFT BECOME ZONAL ON SUNDAY...RESULTING
IN DRIER AND WARMER CONDITIONS AREA WIDE. HOWEVER THE GFS IS
SLOW TO DRY THINGS OUT EAST OF THE MTNS AS IT CONTINUES TO SHOW A
RELATIVELY MOIST SOUTH-SOUTHEAST LOW-LEVEL FLOW FOR MOST OF THE
DAY. WHILE AT THE SAME TIME IT SHOWS ZONAL FLOW ALOFT WITH WAVES
OF MID-LEVEL MOISTURE PASSING BY DURING THE DAY. FOR NOW WILL
LEAVE OUT ANY MENTION OF PRECIP ON SUNDAY. FOR MONDAY AND TUESDAY...
CONFIDENCE IN THE MODELS WAINS AS A FAST NORTHWESTERLY FLOW ON
THE BACK SIDE OF THE PASSING TROUGH MAKES IT DIFFICULT TO PIN DOWN
THE TIMING OF WEAK MID-LEVEL DISTURBANCES WHICH MODELS SHOW
PASSING OVERHEAD. SO WILL KEEP THINGS GENERALLY DRY WITH NEAR TO
SLIGHTLY ABOVE AVERAGE TEMPERATURES. AVERAGE TEMPERATURE FOR
DENVER ON THE MON/18TH AND TUE/19TH IS 83 AND 84...RESPECTIVELY.
AVIATION...LIGHT DRAINAGE WINDS THIS MORNING WILL GRADUALLY SHIFT
MORE SOUTHEAST LATER THIS AFTERNOON. VFR CONDITIONS THROUGH
TONIGHT. SOME SCT-BKN MIDDLE AND HIGH LEVEL MOISTURE LATER TODAY
BUT NO STORMS EXPECTED. THE NEXT COLD FRONT WILL MOVE THROUGH
TERMINALS THURSDAY MORNING...BETWEEN 12-15Z AS WINDS SHIFT
NORTHERLY. A DRY FRONT SO NO STRATUS/FOG IS EXPECTED AT THIS TIME.
HYDROLOGY...NO ISSUES THROUGH TONIGHT WITH A DRY FORECAST.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...COOPER
LONG TERM....BAKER
AVIATION...COOPER
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
333 PM EDT WED JUN 13 2012
.SYNOPSIS...
LOW PRESSURE TO OUR EAST WILL CONTINUE TO PULL FURTHER OFFSHORE
TONIGHT WHILE HIGH PRESSURE NOSES IN FROM THE NORTHWEST. THIS RIDGE
WILL REMAIN COMPLACENT OVER THE REGION THURSDAY THROUGH WEDNESDAY OF
NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
THE WRF-NMMB LOOKED BETTER THAN THE GFS WITH ITS 500MB
INITIALIZATION IN THE NERN CONUS, THE GFS LOOKED BETTER IN OTHER
PLACES EAST. ALSO THE GFS LOOKED SLIGHTLY BETTER AT 850MB AND 925MB.
IN TERMS OF VERIFYING "WHAT IS OUT THERE", THE GFS AND CAN RGEM
LOOKED SLIGHTLY BETTER THAN THE WRF-NMMB. SO THE PLAN IS TO LEAN
TOWARD THE GFS THROUGH THE SHORT TERM AND MOVE THE CHANCES FASTER
THROUGH OUR CWA TONIGHT. THE HRRR WAS NOT USED AS ITS WAVES OF
SHOWERS REACHING INTO PA IS AND HAS NOT BEEN VERIFYING.
SHOWERS CHANCES ARE TIED TO A COMBINATION OF THE GFS, CAN RGEM AND
4KM ARW SOLUTIONS. NOT MUCH DPVA FORECAST BEYOND MIDNIGHT AND NO
OTHER FORCING APPARENT. SOME COASTAL FRICTIONAL CONVERGENCE HELPING
NOW ALONG THE INVERTED TROF. AS THE OFFSHORE LOW SAGS SOUTH, SO
SHOULD THE GREATER CONVERGENCE/SFC TROF AND HENCE THE SOUTHWARD SAG
OF POPS.
OTHERWISE EXPERIMENTAL SATELLITE IMAGERY IS SHOWING A FAIRLY LARGE
SWATH OF MVFR WITH LOW PROBABILITY IFR CIGS OFFSHORE. AS THE SFC LOW
SAGS SOUTHWARD, THE WINDS WILL VEER MORE TOWARD THE ONSHORE
DIRECTION. WITH THE FORECAST SOUNDINGS DEVELOPING AN INVERSION, THIS
SHOULD TRAP THE CLOUDS AND HELP SPREAD IT WESTWARD INTO OUR CWA.
RIGHT NOW WE ARE LEANING MORE TOWARD CLOUDINESS THAN FOG. WE ARE
MAKING SKY COVER MORE PESSIMISTIC TONIGHT. CONFIDENCE AS TO HOW FAR
WEST THIS GETS IS NOT HIGH. BECAUSE WE ARE GOING WITH THE CLOUDIER
FORECAST, WE ARE ALSO GOING WITH HIGHER STAT GUIDANCE MINIMUM
TEMPERATURES.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/...
ONCE THE STRATOCU CEILING IN OUR CWA GETS ESTABLISHED, THE CONTINUING
ONSHORE FLOW MAY HELP TAKE IT A WHILE LONGER THAN TYPICALLY FOR JUNE
FOR SUNSHINE TO DEVELOP ON THURSDAY. WE HAVE GONE THE CONSERVATIVE
ROUTE WITH THE SUNSHINE. ONE KNOWN WEAKNESS OF THE NEW VERSION OF
THE GFS IS EVEN A MORE GENEROUS WET BIAS WITH THE .01 ISOHYET. AT
THE RISK OF PUTTING OUR FOOT IN OUR MOUTHS, THAT IS WHAT THE GFS
LOOKS LIKE ITS DOING IN OUR CWA TOMORROW. ITS GETTING THERE BY
POOLING DEW POINTS INTO THE MID 60S AND GENERATING SOME WEAK CAPE.
ITS OWN STAT GUIDANCE HAS DEW POINTS 5 TO 8F LOWER AND WITHOUT THOSE
DEW POINTS, THE CHANCES GET THAT MUCH LOWER. EVEN WITH FULL SUN AND
OFF THE FORECAST 925MB TEMPERATURES, GFS MOS MAX TEMPS LOOK TOO
WARM. MAX TEMPS CLOSER TO NAM MOS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
5-WAVE MODEL GUIDANCE SHOWS BLOCKING TO OUR NORTHEAST WHERE A
LONGWAVE TROUGH HAS RESIDED FOR THE PAST COUPLE OF DAYS. RIDGING
WILL MOVE INTO THE REGION BY FRIDAY ORIENTED SOUTHWEST TO NORTHEAST.
THIS WILL PROVIDE A STAGNANT PATTERN THROUGH MID-WEEK NEXT WEEK. IT
WILL PROVIDE DRY CONDITIONS WITH SLIGHTLY BELOW NORMAL TEMPERATURES
TO START THE PERIOD. WITH THE STAGNANT PATTERN CONFIDENCE IN THE
LONGTERM FORECAST IS HIGH.
AS THE MID-LEVEL AND SURFACE RIDGING MOVE EVER SO SLIGHTLY TO OUR
EAST ON SUNDAY AND MONDAY OUR SURFACE FLOW WILL TURN MORE TOWARDS
THE SOUTH-SOUTHEAST. THIS WILL ALLOW THICKNESSES TO INCREASE AS
WARMER, MOISTER AIR IS ADVECTED INTO OUR REGION. TEMPERATURES WILL
BEGIN A SLOW UPWARD TREND STARTING ON MONDAY THROUGH THE REMAINDER
OF THE PERIOD.
WITH THE NORTHEASTERLY FLOW TURNING MORE EASTERLY BY SATURDAY WE
WILL SEE DIURNALLY DRIVEN CLOUDS AT NIGHT THROUGH WEDNESDAY...BETTER
CHANCES CLOSER TO THE COAST. DURING THE OVERNIGHT HOURS WE WILL SEE
MOISTURE POOLING IN THE LOW-LEVELS WHICH COULD PRODUCE PROLONGED
PERIODS OF FOG AND OVERCAST CONDITIONS...MOST OF THE LOWER CLOUDS
AND FOG WILL BURN OFF DURING THE MORNING HOURS.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
A TRENDING TOWARD MVFR TAF PACKAGE WAS ISSUED WITH THE 18Z TAFS,
ALTHOUGH CONFIDENCE IS LOWER THAN AVERAGE. THE EASTWARD ADVANCE OF
THE LOWER CLOUDS HAS HIT THE WALL AND THEY ARE SLOWLY ADVANCING
TO THE WEST. SOME SHOWERS ARE EXPECTED TO REMAIN JUST EAST
OF KACY. WE EXPECT THE EASTERN NJ AIRPORTS AND KACY TAF SITE TO
REMAIN MVFR WITH SOME WESTWARD PROGRESSION IN NJ. THE PA AND
DELMARVA AIRPORTS SHOULD REMAIN VFR WITH SOME CUMULUS AND CIRRUS
CLOUDS. GUSTY NORTH WINDS (20 TO 25 KT GUSTS) SHOULD CONTINUE
THROUGH THE AFTERNOON WITH A SLOW VEERING TO THE NORTHEAST.
FOR THIS EVENING WE ARE EXPECTING THE MVFR CIGS TO ADVANCE WESTWARD
EVEN MORE AS IT PROGRESSES. GREATEST CONFIDENCE OF MVFR CONDITIONS
EASTERN TERMINALS, LESS CONFIDENCE ABOUT IT REACHING KABE AND KRDG.
THE WESTERN EDGE OF SHOWERS WILL CONTINUE TO BE NEAR KACY AND KMIV.
NOT ENOUGH CONFIDENCE TO INCLUDE. FORECAST SOUNDINGS SUGGESTING SOME
GUSTINESS MAY CONTINUE INTO THE EVENING, ESPECIALLY EASTERN
TERMINALS. WE BELIEVE THERE WILL BE EITHER TOO MANY CLOUDS OR WINDS
FOR FOG TO FORM OVERNIGHT.
ONCE THE MVFR CIG ARRIVES, IT MAY TAKE A WHILE FOR IT TO DISSIPATE
ON THURSDAY. SO OTHER THAN OUR NW TERMINALS, WE KEPT MVFR CIGS
GOING THROUGH THE MORNING. SOME GUSTINESS FROM THE NORTHEAST
(SLIGHTLY LOWER THAN TODAY) WINDS SHOULD RETURN IN THE MORNING.
THE OVERALL GRADIENT IS EXPECTED TO RELAX DURING THURSDAY
AFTERNOON WHICH MIGHT BE A WINDOW TO HAVE CLOUDS DISSIPATE OR RISE
TO VFR CIGS.
OUTLOOK...
THU NIGHT - WEDNESDAY... VFR CONDITIONS WITH EAST-NORTHEAST WINDS.
POSSIBLE LOCAL MVFR CONDITIONS DURING THE OVERNIGHT AND EARLY
MORNING HOURS...MAINLY EAST OF PHILADELPHIA.
&&
.MARINE...
WE WILL EXTEND THE SCA ON DELAWARE BAY THROUGH THE NIGHT. FORECAST
SOUNDINGS ARE NOW SHOWING SMALL CRAFT ADVISORY WINDS NEAR THE TOP OF
THE MIXING LEVEL THROUGH THE NIGHT. IT IS PROBABLE THAT WE WILL GO
BELOW SMALL CRAFT ADVISORY LEVEL GUSTS FROM TIME TO TIME THE REST OF
THIS AFTERNOON AND EVENING, BUT AS AIR TEMPERATURES EDGE BELOW THE
WATER TEMPERATURES OVERNIGHT, THERE MAY BE ANOTHER WINDOW FOR MORE
FREQUENT SCA LEVEL GUSTS. THE OVERALL GRADIENT IS EXPECTED
TO BE LESSEN ON THURSDAY, SO THE CHANCES FOR SCA CRITERIA WILL
DECREASE AS THE DAY PROGRESSES ON THE BAY.
ON THE OCEAN, SMALL CRAFT ADVISORY LEVEL WINDS SHOULD OCCUR TONIGHT
AND THEN INTO THURSDAY ON THE SOUTHERN WATERS. SWELLS WILL BE A
CONTINUING AND LAGGING ISSUE ONCE THE WINDS CEASE AS THE OVERALL
ONSHORE FLOW SHOULD PERSIST FOR A WHILE. WE DID NOT EXTEND THE SCA
ON THE OCEAN FOR EITHER SEGMENTS, BUT SOME ADJUSTMENTS MAY BECOME
NECESSARY AS CONFIDENCE INCREASES.
OUTLOOK...
HIGH PRESSURE WILL BUILD IN FROM THE NORTHWEST AND SLIDE TO OUR
NORTHEAST BY SATURDAY. THIS WILL PROVIDE DRY WEATHER ALTHOUGH WITH AN
ONSHORE FLOW WE COULD STILL HAVE SOME LINGERING ISSUES WITH SWELLS
ACROSS OUR SOUTHERN WATERS THROUGH SATURDAY. AFTER THAT SEAS WILL
BECOME MORE TRANQUIL AS WE LOSS THE SWELLS.
&&
.RIP CURRENTS...
THE COMBINATION OF LARGE...8 SECOND PERIOD SWELLS AND FAIRLY HIGH
SURF ZONE WAVES WILL INTERACT TO CREATE A HIGH RISK OF RIP CURRENTS
FOR BOTH THE NEW JERSEY AND DELAWARE COASTS FOR THURSDAY. DUE TO THE
HIGH RISK...A HIGH RIP CURRENT RISK HEADLINE WILL BE ISSUED FOR
THURSDAY. THE DETAILS OF THE HIGH RIP CURRENT RISK CAN BE FOUND IN
THE COASTAL HAZARD MESSAGE PRODUCT /AWIPS HEADER PHLCFWPHI/.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...HIGH RIP CURRENT RISK FROM THURSDAY MORNING THROUGH THURSDAY
EVENING FOR NJZ014-024>026.
DE...HIGH RIP CURRENT RISK FROM THURSDAY MORNING THROUGH THURSDAY
EVENING FOR DEZ004.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 9 PM EDT THURSDAY FOR ANZ452>455.
SMALL CRAFT ADVISORY UNTIL 7 AM EDT THURSDAY FOR ANZ430-431-
450-451.
&&
$$
SYNOPSIS...HEAVENER
NEAR TERM...GIGI
SHORT TERM...GIGI
LONG TERM...HEAVENER
AVIATION...GIGI/HEAVENER
MARINE...GIGI/HEAVENER
RIP CURRENTS...HAYES
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1208 PM CDT WED JUN 13 2012
.DISCUSSION...
ISSUED 947 AM CDT WED JUN 13 2012
THUNDERSTORM COMPLEX...ASSOCIATED WITH A SHORTWAVE OVER SOUTH
DAKOTA...HAS BEEN WEAKENING AS IT MOVES THROUGH WESTERN IOWA.
DRIER AIR OVER ILLINOIS WILL PREVENT THE RAIN FROM MAKING IT AS
FAR AS OUR AREA...BUT THICKENING MID AND HIGH CLOUDS FROM THIS
SYSTEM HAVE BEGUN MOVING INTO THE WESTERN CWA. LATEST LAYER
HUMIDITY PLOTS FROM THE RAP MODEL SHOWING THE THICKEST CLOUDS TO
PASS JUST TO OUR NORTH THROUGH MID AFTERNOON...WITH SCATTERED
CLOUDS SOUTHWARD OVER MOST OF THE CWA. HAVE SENT OUT SOME
ZONE/GRID UPDATES TO INCREASE THE CLOUD COVER SOMEWHAT OVER THE
NORTHERN CWA FOR TODAY. CURRENT TEMPERATURE FORECASTS LARGELY ARE
ON TRACK AND MADE ONLY VERY MINOR MODIFICATIONS BASED ON OBSERVED
TRENDS.
GEELHART
&&
.AVIATION...
ISSUED 1207 PM CDT WED JUN 13 2012
EASTERLY WINDS WILL PERSIST THROUGH ABOUT 06Z...BEFORE TRENDING
SOUTHEAST AS A COLD FRONT BEGINS TO PUSH THROUGH THE CENTRAL
PLAINS. SOME INCREASE IN SPEED IS EXPECTED TOWARD THE END OF THE
PERIOD AS THE FRONT GETS CLOSER. EXPECT PERIODIC CLOUD COVER TO
REMAIN AT OR ABOVE 12 KFT DUE TO DRY AIR IN THE LOWER LEVELS OF
THE ATMOSPHERE.
GEELHART
&&
.PREV DISCUSSION...
ISSUED 249 AM CDT WED JUN 13 2012
AT 06Z A BROAD AREA OF 1020 MB HIGH PRESSURE OCCUPIED MUCH OF THE
UPPER MIDWEST AND GREAT LAKES. UNDER THIS RIDGE CLEAR SKIES AND
LIGHT WINDS ALLOWED EARLY MORNING TEMPERATURES TO DIP INTO
THE SEASONABLY COOL 50S LOCALLY. AT THE MID LEVELS ZONAL FLOW
DOMINATED MUCH OF THE CENTRAL AND WESTERN U.S. WITH TROUGHING
AFFECTING THE EASTERN THIRD OF THE COUNTRY. A SHORTWAVE OVER THE
DAKOTAS WAS PRODUCING SOME SHOWERS AS FAR EAST AS WESTERN IOWA. AFTER
ANOTHER COMFORTABLE DAY TODAY...WARMING BEGINS THURSDAY THEN 90+
DEGREE HEAT IS EXPECTED FRIDAY THROUGH THE WEEKEND WHEN A MID LEVEL
RIDGE STRENGTHENS OVERHEAD. RAIN CHANCES INCREASE FROM THE NW
EARLY NEXT WEEK...OR WHEN THE RIDGE FINALLY SHIFTS FARTHER EAST.
SHORT TERM...TODAY THROUGH FRIDAY
AS THE HIGH SLIPS INTO THE EASTERN GREAT LAKES...EASTERLY LLVL
FLOW WILL KEEP TEMPS SIMILAR TO OBSERVED HIGHS YESTERDAY...IN THE
UPPER 70S/LOWER 80S. HUMIDITY LEVELS TO REMAIN REMARKABLY LOW FOR
MID JUNE WITH DEWPOINTS IN THE 40S. A SHORTWAVE CURRENTLY OVER THE
DAKOTAS WILL SHIFT INTO THE FAR UPPER MIDWEST KEEPING ANY PRECIP
NORTHWEST OF THE AREA...HOWEVER AN INCREASE IN MID/HIGH LEVEL CLOUDS
MAY PREVENT A SECOND COMPLETELY SUNNY DAY AT LEAST ACROSS THE
NORTHERN CWA. QUIET WEATHER PREVAILS OVERNIGHT WITH LOWS
MODERATING A FEW DEGREES FROM WHAT IS SEEN THIS MORNING. RETURN
SOUTHERLY FLOW COMMENCES ON THURSDAY IN CONCERT WITH RISING
HEIGHTS WILL PUSH TEMPS BACK UP NEAR SEASONAL NORMALS.
BY FRIDAY...LOW TO MID LEVEL THERMAL RIDGE BUILDS OVERHEAD AS A
LARGE MID LEVEL HIGH PRESSURE RIDGE STRENGTHENS FROM THE EASTERN
GREAT LAKES SOUTHWEST TOWARDS TX. THIS WILL RETURN HIGHS TO THE
90S. DRY SOILS WILL HELP KEEP DEWPOINTS IN CHECK...GRADUALLY
RISING THROUGH THE 50S FOR TOLERABLE HUMIDITY LEVELS.
LONG TERM...SATURDAY THROUGH TUESDAY
PRIMARY WEATHER FEATURES FOR THE EXTENDED PORTION OF THE FORECAST
ARE THE EXTENT/DURATION OF HEAT INTO EARLY NEXT WEEK...AND THE
POTENTIAL RETURN OF MUCH NEEDED RAINS BY MONDAY/TUESDAY OR LATER. EACH
OF THESE ELEMENTS WILL BE DETERMINED BY THE STRENGTH OF THE RIDGE
AND HOW QUICKLY IT SHIFTS FAR ENOUGH EAST TO ALLOW AN ACTIVE WX
PATTERN TO OUR NORTHWEST TO MOVE IN. FOR NOW WILL KEEP SLIGHT TO
LOW CHANCE POPS MONDAY/TUESDAY ACROSS THE NORTHWEST HALF WITH THE
ECMWF WEAKENING THE RIDGE QUICKER THAN GFS...WHICH WOULD ALLOW
ORGANIZED CONVECTION TO SETTLE SOUTHEAST TOWARDS CENTRAL IL. UNTIL
THE RIDGE DAMPENS...HIGHS IN THE LOWER 90S ARE LIKELY.
25
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
948 AM CDT WED JUN 13 2012
.DISCUSSION...
ISSUED 947 AM CDT WED JUN 13 2012
THUNDERSTORM COMPLEX...ASSOCIATED WITH A SHORTWAVE OVER SOUTH
DAKOTA...HAS BEEN WEAKENING AS IT MOVES THROUGH WESTERN IOWA.
DRIER AIR OVER ILLINOIS WILL PREVENT THE RAIN FROM MAKING IT AS
FAR AS OUR AREA...BUT THICKENING MID AND HIGH CLOUDS FROM THIS
SYSTEM HAVE BEGUN MOVING INTO THE WESTERN CWA. LATEST LAYER
HUMIDITY PLOTS FROM THE RAP MODEL SHOWING THE THICKEST CLOUDS TO
PASS JUST TO OUR NORTH THROUGH MID AFTERNOON...WITH SCATTERED
CLOUDS SOUTHWARD OVER MOST OF THE CWA. HAVE SENT OUT SOME
ZONE/GRID UPDATES TO INCREASE THE CLOUD COVER SOMEWHAT OVER THE
NORTHERN CWA FOR TODAY. CURRENT TEMPERATURE FORECASTS LARGELY ARE
ON TRACK AND MADE ONLY VERY MINOR MODIFICATIONS BASED ON OBSERVED
TRENDS.
GEELHART
&&
.AVIATION...
ISSUED 644 AM CDT WED JUN 13 2012...FOR THE 12Z TAFS
VFR CONDITIONS WILL CONTINUE OVER THE NEXT 24 HOURS UNDER DRY
CANADIAN HIGH PRESSURE. CIRRUS CLOUDS FROM CONVECTIVE DEBRIS OVER
THE PLAINS SHOULD BE THE PRIMARY CLOUD COVER OVER THE TERMINALS
TODAY. THE LOW AND MID LEVELS WILL REMAIN TOO DRY FOR MUCH IN THE
WAY OF FAIR WEATHER CUMULUS.
LIKEWISE...VISIBILITY SHOULD REMAIN UNRESTRICTED DUE TO THE VERY
LOW SURFACE DEWPOINTS.
WINDS WILL CLIMB BETWEEN 10-12KT FROM THE ESE DURING THE
DAY...THEN DIMINISH BELOW 10KT BY SUNSET.
SHIMON
&&
.PREV DISCUSSION...
ISSUED 249 AM CDT WED JUN 13 2012
AT 06Z A BROAD AREA OF 1020 MB HIGH PRESSURE OCCUPIED MUCH OF THE
UPPER MIDWEST AND GREAT LAKES. UNDER THIS RIDGE CLEAR SKIES AND
LIGHT WINDS ALLOWED EARLY MORNING TEMPERATURES TO DIP INTO
THE SEASONABLY COOL 50S LOCALLY. AT THE MID LEVELS ZONAL FLOW
DOMINATED MUCH OF THE CENTRAL AND WESTERN U.S. WITH TROUGHING
AFFECTING THE EASTERN THIRD OF THE COUNTRY. A SHORTWAVE OVER THE
DAKOTAS WAS PRODUCING SOME SHOWERS AS FAR EAST AS WESTERN IOWA. AFTER
ANOTHER COMFORTABLE DAY TODAY...WARMING BEGINS THURSDAY THEN 90+
DEGREE HEAT IS EXPECTED FRIDAY THROUGH THE WEEKEND WHEN A MID LEVEL
RIDGE STRENGTHENS OVERHEAD. RAIN CHANCES INCREASE FROM THE NW
EARLY NEXT WEEK...OR WHEN THE RIDGE FINALLY SHIFTS FARTHER EAST.
SHORT TERM...TODAY THROUGH FRIDAY
AS THE HIGH SLIPS INTO THE EASTERN GREAT LAKES...EASTERLY LLVL
FLOW WILL KEEP TEMPS SIMILAR TO OBSERVED HIGHS YESTERDAY...IN THE
UPPER 70S/LOWER 80S. HUMIDITY LEVELS TO REMAIN REMARKABLY LOW FOR
MID JUNE WITH DEWPOINTS IN THE 40S. A SHORTWAVE CURRENTLY OVER THE
DAKOTAS WILL SHIFT INTO THE FAR UPPER MIDWEST KEEPING ANY PRECIP
NORTHWEST OF THE AREA...HOWEVER AN INCREASE IN MID/HIGH LEVEL CLOUDS
MAY PREVENT A SECOND COMPLETELY SUNNY DAY AT LEAST ACROSS THE
NORTHERN CWA. QUIET WEATHER PREVAILS OVERNIGHT WITH LOWS
MODERATING A FEW DEGREES FROM WHAT IS SEEN THIS MORNING. RETURN
SOUTHERLY FLOW COMMENCES ON THURSDAY IN CONCERT WITH RISING
HEIGHTS WILL PUSH TEMPS BACK UP NEAR SEASONAL NORMALS.
BY FRIDAY...LOW TO MID LEVEL THERMAL RIDGE BUILDS OVERHEAD AS A
LARGE MID LEVEL HIGH PRESSURE RIDGE STRENGTHENS FROM THE EASTERN
GREAT LAKES SOUTHWEST TOWARDS TX. THIS WILL RETURN HIGHS TO THE
90S. DRY SOILS WILL HELP KEEP DEWPOINTS IN CHECK...GRADUALLY
RISING THROUGH THE 50S FOR TOLERABLE HUMIDITY LEVELS.
LONG TERM...SATURDAY THROUGH TUESDAY
PRIMARY WEATHER FEATURES FOR THE EXTENDED PORTION OF THE FORECAST
ARE THE EXTENT/DURATION OF HEAT INTO EARLY NEXT WEEK...AND THE
POTENTIAL RETURN OF MUCH NEEDED RAINS BY MONDAY/TUESDAY OR LATER. EACH
OF THESE ELEMENTS WILL BE DETERMINED BY THE STRENGTH OF THE RIDGE
AND HOW QUICKLY IT SHIFTS FAR ENOUGH EAST TO ALLOW AN ACTIVE WX
PATTERN TO OUR NORTHWEST TO MOVE IN. FOR NOW WILL KEEP SLIGHT TO
LOW CHANCE POPS MONDAY/TUESDAY ACROSS THE NORTHWEST HALF WITH THE
ECMWF WEAKENING THE RIDGE QUICKER THAN GFS...WHICH WOULD ALLOW
ORGANIZED CONVECTION TO SETTLE SOUTHEAST TOWARDS CENTRAL IL. UNTIL
THE RIDGE DAMPENS...HIGHS IN THE LOWER 90S ARE LIKELY.
25
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
351 PM CDT WED JUN 13 2012
.SYNOPSIS...
ISSUED AT 342 PM CDT WED JUN 13 2012
A BROAD WEAK, ZONAL MID LEVEL FLOW PATTERN WA IN PLACE ACROSS
WESTERN KANSAS. INCREASING BOUNDARY LAYER MOISTURE WAS OCCURRING AS
SOUTHERLY WINDS TRANSPORTED HIGHER CONTENT MOISTURE AIR FROM
WESTERN OKLAHOMA AND THE PANHANDLES. FARTHER WEST, A DRYLINE WAS
EVIDENT IN THE MESONET POINT DATA ACROSS SOUTHEAST COLORADO, AS WELL
AS IN A FINE LINE DEVELOPING ON KPUX RADAR FROM LAMAR, CO
SOUTHWEST.
&&
.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 342 PM CDT WED JUN 13 2012
THE SHORT TERM MODELS HANDLE THE EVOLUTION OF CONVECTION THIS EVENING
VERY DIFFERENTLY AND THERE IS RELATIVELY LOW CONFIDENCE IN THIS
NEAR TERM FORECAST. THE 12UTC NAM MODEL WOULD INDICATE AND STORMS
THAT DEVELOP REMAIN ANCHORED TO THE MUCH HIGHER CAPE/INSTABILITY
AXIS OF THE HIGH PLAINS OF COLORADO INTO THE WEST TEXAS PANHANDLE
THIS EVENING. AT HIS TIME, THIS NAM SOLUTION SEEMS TO BE MORE
LIKELY THAN OTHERS BASED ON THE WEAK FORCING ENVIRONMENT WE ARE
DEALING WITH. HOWEVER, WE CANNOT COMPLETELY IGNORE THE RECENT
ARW-WRF/NMM RUNS AND HRRR THAT HAVE ELUDED TO CONVECTION OVER
EASTERN COLORADO LATER THIS AFTERNOON DEVELOPING A COLD POOL AND
SPREADING RAPIDLY INTO THE WESTERN SEVERAL TIERS OF COUNTIES IN THE
EVENING HOURS. IF THAT DOES OCCUR, THE MOST PLAUSIBLE OUTCOME WOULD
SEEM TO BE MARGINALLY ISOLATED SEVERE THUNDERSTORM WIND GUSTS AND
PERHAPS ISOLATED HAIL PUSHING SEVERE LIMITS OF AN INCH AT MOST.
HOWEVER, THE WEAKER CONVECTION COULD SPREAD FOR SEVERAL HOURS
EASTWARD INTO CENTRAL KANSAS DURING THE LATE EVENING.
CONVECTIVE CHANCES ARE JUST AS GOOD OR BETTER ALONG A STRENGTHENING
COLD FRONTAL BOUNDARY WHICH SHOULD UNDERGO FRONTOGENESIS FROM WEST
CENTRAL KANSAS INTO NORTH CENTRAL KANSAS DURING THE VERY LATE
AFTERNOON INTO THURSDAY EVENING. THIS WILL BE BE WEAK FORCING,
BUT PERHAPS MORE MODERATE CAPE VALUES BY LATE IN THE DAY.
ISOLATED SEVERE CONVECTION COULD BE FOUND THROUGH THE INTERSTATE
70 CORRIDOR, WESTWARD TO SCOTT CITY LATE IN THE AFTERNOON
THURSDAY, BUT WIDESPREAD SEVERE IS NOT ANTICIPATED. THE NAM MODEL
IS INDICATING THE WARMEST TEMPERATURES AROUND 100 DEGREES, WHILST
MOST OTHER NUMERICAL OUTPUT IS INDICATING LOW 90S. TEMPERATURES
SHOULD WARM TO SOMEWHERE IN THE MIDDLE THURSDAY AFTERNOON ACROSS
SOUTHWEST AND CENTRAL KANSAS.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 302 PM CDT WED JUN 13 2012
THE EXTENDED PERIOD BEGINNING FRIDAY WILL SEE ONE UPPER SHORT WAVE
EXITING THE WESTERN PLAINS OF KANSAS, BRINGING ABOUT A 40 TO 50
PERCENT CHANCE OF THUNDERSTORMS NEAR THE I-70 CORRIDOR AND
NORTHWARD, EARLY THURSDAY NIGHT. AFTER MIDNIGHT THURSDAY, THE
PRECIP CHANCES WILL CHANGE TO 30 TO 40 PERCENT, AND ONLY IN TREGO,
ELLIS AND RUSH COUNTIES. THE NAM MODEL IS HINTING AT QPF FROM 0.60
TO 0.80-INCH IN OUR NORTHWEST FROM HAYS TO SCOTT CITY, BUT HAVE A
HARD TIME BUYING THAT MUCH PERCEPTIBLE WATER WILL FALL OUT, BASED
ON RECENT TRENDS. TRIMMED THURSDAY NIGHT QPF TO AROUND 0.25 TO
0.30-INCH. AS THAT SHORT WAVE EXITS, ANOTHER SMALL SCALE WAVE IS
EJECTED FROM THE LARGE UPPER LOW OFF THE COAST OF BAJA CALIFORNIA.
THIS SECOND WAVE IS LESS ORGANIZED THAN THE FIRST, AND WILL BRING
THUNDERSTORM CHANCES TO THAT AREA NORTH OF A LINE FROM JOHNSON
CITY TO LA CROSSE. THE UPPER BAJA LOW CUTS OFF SATURDAY NIGHT PER
THE ECMWF AND GFS MODELS, AND AN UPPER HIGH BEGINS TO BUILD OVER
TEXAS. FOR NOW, PLAN TO KEEP SUNDAY AND SUNDAY NIGHT FREE OF
PRECIPITATION CHANCES, BUT OUR EXTREME EAST WILL HAVE A SLIGHT
CHANCE MONDAY AFTERNOON AS UPPER DIVERGENCE WILL BE OVERHEAD, AND
A DOWN SLOPE FLOW WILL BE EVOLVING. A COLD FRONT WILL SINK INTO
SOUTHWEST KANSAS MONDAY NIGHT, AND THERE COULD BE A FEW SCATTERED
STORMS IN OUR SOUTHEAST ZONES WHERE THE GREATEST MOISTURE WILL BE,
SUCH AS SOUTHEAST OF LINE FORM LARNED TO DODGE CITY TO ASHLAND
MONDAY NIGHT. THE CR-EXTENDED BLEND PROCEDURE PLACED 30 POPS IN
MY EXTREME THREE EASTERN COUNTIES OF STAFFORD, PRATT AND BARBER
WEDNESDAY, OR DAY 7. KNOCKED THOSE POPS DOWN TO 20 PERCENT, AS THE
TIMING AND PLACEMENT OF THE NEXT WAVE COULD BE JUST ABOUT ANYWHERE
AROUND THAT TIME.
TEMPERATURES WILL BE RELATIVELY HOT DURING THE EXTENDED. OVERNIGHT
MINIMUM TEMPERATURES WILL GENERALLY BE IN THE MID 60S TO LOWER 70S
(SE, PRATT AND BARBER COUNTIES), WITH PERHAPS MONDAY NIGHT/TUESDAY
MORNING THE COOLEST MORNING WITH MIN TEMPS FROM THE LOWER 60S IN
SCOTT CITY TO 70 DEGREES IN MEDICINE LODGE. MAXIMUM TEMPERATURES
WILL START OUT FRIDAY IN THE LOWER 90S NORTH OF I-70 AND RANGE TO
THE MID 90S ALONG THE OKLAHOMA BORDER. BY SUNDAY, MAXIMUM
TEMPERATURES WILL BE IN THE LOWER TO MID 90S ACROSS ALL OF SOUTHWEST
KANSAS, THEN WARM TO PERHAPS THE WARMEST DAY MONDAY. HIGHS MONDAY
SHOULD TOP OUT IN THE MID TO UPPER 90S, WITH THE ELKHART AREA
BEING NEAR THE CENTURY MARK. THE WEAK COLD FRONT WILL SLIP THROUGH
MONDAY NIGHT (BEST GUESS), AND KNOCK HIGHS DOWN A NOTCH INTO THE
LOWER TO MID 90S BOTH TUESDAY AND WEDNESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1257 PM CDT WED JUN 13 2012
A NARROW STRIP OF MID LEVEL (9-10KFT) LEVEL ACCAS WAS NOTED ON
VISIBLE SATELLITE BETWEEN KDDC AND KHYS. OTHER THAN THIS STRIP OF
CLOUDS, THE SKY WAS CLEAR ACROSS THE AREA. MID LEVEL INSTABILITY MAY
ALLOW ADDITIONAL CLOUDS TO DEVELOP THROUGH THE AFTERNOON ON THE MID
LAYERS, AND VERY SMALL CONVECTIVE CHANCES ARE ANTICIPATED FOR THE
EVENING (AFTER 00 UTC PERIOD). AND STORMS THAT MIGHT DEVELOP WILL
PROBABLY BE HIGH BASED AND ONLY MAY AFFECT THE KGCK TERMINAL.
CONFIDENCE IS LOW ENOUGH HOWEVER TO NOT MENTION AT THIS TIME IN THE
KGCK TERMINAL AT THIS TIME.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 67 96 70 93 / 20 20 20 20
GCK 68 97 70 93 / 20 20 30 20
EHA 67 96 69 91 / 20 20 20 20
LBL 68 96 71 93 / 20 10 20 20
HYS 68 97 68 90 / 20 30 50 20
P28 68 95 76 94 / 20 20 20 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RUSSELL
SHORT TERM...RUSSELL
LONG TERM...BURKE
AVIATION...RUSSELL
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
627 PM EDT WED JUN 13 2012
.SYNOPSIS...
HIGH PRESSURE WILL BRING DRY AND COOL AIR OVER THE UPPER OHIO VALLEY
OVERNIGHT THROUGH THE END OF THE WEEK. THE STRETCH OF NICE
WEATHER WILL CONTINUE THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH THURSDAY/...
AN EARLY EVENING ENHANCED SHORT TERM FORECAST UPDATE HAS BEEN
ISSUED WITH LITTLE CHANGE OTHER THAN TO INCREASE SKY GRIDS SLIGHTLY
OVERNIGHT AS CIRRUS PASSES OVER THE AREA.
THE LATEST RAP MID-LEVEL ANALYSIS INDICATES A 500MB RIDGE AXIS
CENTERED ACROSS THE UPPER OHIO VALLEY WITH A DEEP LAYER OF DRY AIR
IN PLACE. AT THE SURFACE, HIGH PRESSURE IS CENTERED ACROSS
MICHIGAN. IN THIS PATTERN, SKIES ARE CLEAR WITH LIGHT AND NORTHERLY
WINDS ACROSS THE AREA.
THE MID-LEVEL RIDGE AXIS WILL SLOWLY NUDGE EASTWARD OVERNIGHT WITH
THE HIGH SHIFTING INTO EASTERN CANADA ON THURSDAY. THE DRY PROFILE
ALOFT WILL REMAIN IN PLACE ASIDE FROM SOME THIN CIRRUS CROSSING
THE AREA OVERNIGHT. CIRRUS WILL PASS ON THURSDAY, WITH ANOTHER
CLEAR DAY EXPECTED ACROSS THE AREA. DESPITE THIN CIRRUS CROSSING
THE AREA, A STRONG RADIATIONAL COOLING NIGHT IS EXPECTED. OVERNIGHT
LOWS ARE CLOSER TO THE WARMER MET GUIDANCE, RANGING FROM THE UPPER
40S TO LOWER 50S. WITH 850 TEMPS WARMING TO 11-13C TOMORROW AND
ABUNDANT SUNSHINE, HIGHS WILL WARM TO NEAR NORMAL SEASONAL VALUES.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY/...
STRONG SURFACE HIGH TONIGHT WILL STAY OVER THE GREAT LAKES AND
BRING LIGHT NORTH WINDS TO THE REGION. RADITIONAL COOLING WILL
BRING TEMPERATURES DOWN TO THE 50S AND 40S.
SURFACE HIGH AND STRENGTHENING EASTERN RIDGE WILL ALLOW FOR
COMFORTABLE CONDITIONS AND PLENTY OF SUNSHINE THROUGH THE REST OF
THE PERIOD. NEAR NORMAL TEMPS THURSDAY THROUGH SATURDAY WITH JUST
A COUPLE OF DEGREES ABOVE THE NORMAL HIGH.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
SATURDAY NIGHT THROUGH WEDNESDAY...MODEL AGREEMENT IS RATHER
STRONG WITH REGARD TO THE DEVELOPMENT AND AMPLIFICATION OF AN
UPPER RIDGE OVER THE EASTERN THIRD OF THE U.S. THROUGH THE
EXTENDED FORECAST PERIOD. RUN-TO-RUN MODEL VARIATION HAS BEEN
VIRTUALLY NIL...AND OTHER THAN A POSSIBLE IMPULSE RUNNING OVER
THE RIDGE AXIS...THE CHANCES FOR PRECIPITATION THROUGHOUT THE
EXTENDED FORECAST ARE FAIRLY LOW.
WITH SURFACE HIGH PRESSURE IN CONTROL AND AN UPPER RIDGE AXIS
TRANSITING THE AREA...COMPRESSIONAL WARMING AND INCREASING MIXING
BEYOND NEXT WEEKEND WILL ALLOW TEMPERATURES TO SURGE WELL ABOVE
NORMAL. AS MODEL CONSENSUS 850 MB TEMPERATURES RUN FROM ROUGHLY
16C UP TOWARD 20C...THE POSSIBILITY OF ECLIPSING 90F IN SOME
LOCATIONS INCREASES DAY-BY-DAY THROUGH THE MIDDLE OF NEXT WEEK. AT
THIS TIME...THE RIDGE BREAKDOWN FOR OUR AREA STILL SEEMS TO BE FAR
ENOUGH OUT INTO THE FUTURE TO BE BEYOND THE FORECAST
PERIOD...HOWEVER THE ECMWF BECOMES SOMEWHAT FLATTER BY THE MIDDLE
OF NEXT WEEK SUCH THAT A FEW SHOWERS OR THUNDERSTORMS IN AFTERNOON
INSTABILITY CANNOT BE RULED OUT...PARTICULARLY NORTH OF
PITTSBURGH. HOWEVER...ALL THINGS CONSIDERED...A DRY SUMMERLIKE
PATTERN LOOKS TO CONTINUE FOR THE EASTERN THIRD OF THE COUNTRY.
FRIES
&&
.AVIATION /22Z WEDNESDAY THROUGH MONDAY/...
HIGH PRESSURE WILL TRANSIT THE GREAT LAKES...LEAVING OUR AREA TO
ITS SOUTH OVER THE NEXT 24-30 HOURS. OVERNIGHT INVERSIONS SHOULD
FORM AND ALLOW LIGHT/VARIABLE WINDS EVERYWHERE...HOWEVER AS
DAYTIME THURSDAY ENSUES...WINDS SHOULD TURN LIGHT EASTERLY FOR US
AROUND THE SOUTH SIDE OF THE SURFACE HIGH. SKIES SHOULD REMAIN
MOSTLY CLEAR WITH ONLY AN OUTSIDE SHOT AT SOME CIRRUS...SO VFR
CONDITIONS WILL BE THE RULE.
.OUTLOOK...WEDNESDAY NIGHT THROUGH SUNDAY...
HIGH PRESSURE WILL ALLOW FOR VFR CONDITIONS TO PREVAIL ACROSS THE
TERMINALS THROUGH SUNDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1151 PM EDT THU JUN 14 2012
.SYNOPSIS...
ISSUED AT 330 PM EDT THU JUN 14 2012
AN UPPER LEVEL RIDGE OVER THE LOWER GREAT LAKES REGION WILL CONTINUE
TO PRODUCE PREDOMINANTLY DRY WEATHER THROUGH SATURDAY AFTERNOON. A
FEW LIGHT SHOWERS MAY CLIP NORTH CENTRAL LOWER MICHIGAN TONIGHT
BEFORE DISSIPATING. TEMPERATURES WILL UNDERGO A MODERATING TREND
FRIDAY AND SATURDAY WITH WINDS STAYING OUT OF THE SOUTH. A WEAKENING
FRONTAL BOUNDARY WILL BRING THE NEXT CHANCE OF SHOWERS AND
THUNDERSTORMS SATURDAY NIGHT AND SUNDAY. TEMPERATURES WILL CONTINUE
TO AVERAGE AT LEAST TEN TO FIFTEEN DEGREES ABOVE NORMAL FOR MOST OF
NEXT WEEK.
&&
.UPDATE...
ISSUED AT 952 PM EDT THU JUN 14 2012
WE HAVE GONE AHEAD AND UPDATED THE FCST THIS EVENING TO PULL THE
CHC OF RAIN UP NORTH DURING THE OVERNIGHT HOURS. WE ALSO TOUCHED
UP TEMPS A LITTLE TO ACCOUNT FOR THE LATEST TRENDS.
LATEST REGIONAL RADAR TRENDS INDICATE THAT THE BAND OF PCPN ACROSS
WI AND WRN UPPER MI CONTINUES TO PRETTY MUCH HOLD IN PLACE AND IS
NOT MAKING MUCH PROGRESS TOWARD THE CWFA. MOST MODEL DATA
INDICATES THAT THE LLJ AND ASSOCIATED MOISTURE TRANSPORT LINES UP
WELL WITH THE PCPN...AND KEEPS IT TO OUR WEST AND EVENTUALLY NORTH
TONIGHT. DEEP LAYER THICKNESSES WOULD SUPPORT IT PROPAGATING
TOWARD THE AREA...HOWEVER THE VERY DRY AIR IN PLACE HAS AND IS
EXPECTED TO CONTINUE TO DRY IT UP BEFORE IT MAKES IT HERE.
&&
.SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT)
ISSUED AT 330 PM EDT THU JUN 14 2012
PRIMARY SHORT TERM FCST CHALLENGES INVOLVE DETERMINING HOW WARM IT
WILL BECOME FRIDAY AND SATURDAY AND TO EVALUATE POTENTIAL FOR
SHOWERS AND TSTORMS LATE SATURDAY NIGHT. WE ALSO NEED TO DETERMINE
POTENTIAL FOR ANY SHOWERS FROM A DISSIPATING MCS OVER NORTHERN WI
ATTM TO CLIP OUR AREA OVERNIGHT.
A CONSENSUS OF 12Z SHORT RANGE GUIDANCE SUGGESTS MCS ACTIVITY OVER
NORTHERN WI/SOUTHERN MN WILL STAY TO OUR NW TONIGHT. THAT IS WHERE
STRONG FORCING FROM THE LLJ WILL CONTINUE TO FOCUS CONVECTIVE
DEVELOPMENT/REDEVELOPMENT. IT IS NOT IMPOSSIBLE THAT SOME DYING
SHOWERS OVERNIGHT MAY FLIRT WITH OUR NORTHERNMOST COUNTIES (MAINLY
NORTH OF A LINE FROM LDM TO MOP) AS SUGGESTED BY THE HRRR AND
EXTRAPOLATION OF CURRENT RGNL RADAR TRENDS.
I HAVE ADDED MENTION OF JUST A SLIGHT CHC OF SHOWERS ACROSS OUR
NORTHERNMOST TIER OF COUNTIES LATE TONIGHT TO ACCOUNT FOR THIS. LAPS
SOUNDINGS FROM ACROSS OUR FCST AREA LOOK VERY DRY THOUGH AND I WOULD
EXPECT THE EASTERN WING OF THE DECAYING MCS TO CONTINUE TO WEAKEN
OVER EASTERN WI WHILE NEW CONVECTION TAKES OFF OVER WESTERN WI WHERE
THE ROBUST LLJ FORCING IS. WE WILL MAINLY JUST SEE MID TO HIGH LEVEL
CLOUD BLOWOFF FROM THAT ACTIVITY CONTINUE TO ADVECT IN FROM THE NW
LATE THIS AFTN/TONIGHT.
FAIR/MILDER WX ANTICIPATED FRIDAY WITH THE UPPER RIDGE IN PLACE. MAX
TEMPS TOMORROW WILL REACH THE MID TO UPPER 80S IN CONTINUED
SOUTHERLY FLOW WAA AND WITH H8 TEMPS REACHING 17-18 C BY TOMORROW
AFTN.
HOT CONDITIONS ANTICIPATED FOR SATURDAY WITH SOUTHERLY FLOW WAA
CONTINUING AND H8 TEMPS MODERATING TO 19 TO 20 C. THIS SHOULD RESULT
IN MAX TEMPS REACHING THE UPPER 80S TO LOWER 90S. INCREASING MID TO
HIGH CLOUDS FROM THE WEST SATURDAY AFTERNOON WILL NOT INHIBIT IT
FROM BECOMING HOT BY SATURDAY AFTERNOON.
WILL CARRY LOW CHC POPS FOR SCATTERED SHOWERS/TSTORMS VERY LATE
SATURDAY NIGHT. THIS BASED LARGELY ON 12Z GFS GUIDANCE SHOWING THE
APPROACH OF THE WEAKENING FRONT AND INCREASING 1000-850 MB MOISTURE
TRANSPORT DEVELOPING OVERNIGHT.
HOWEVER IT IS NOTED THAT 12Z NAM GUIDANCE KEEPS IT DRY THRU 12Z
SUNDAY AND THE 00Z/12Z ECMWF ONLY BRINGS A FEW SHOWERS INTO OUR NW
FCST AREA TOWARD DAYBREAK SUNDAY. SO OVERALL IT STILL LOOKS LIKE A
(SLIGHTLY) BETTER CHC FOR A FEW SHOWERS/STORMS WILL HOLD OFF UNTIL
SUNDAY.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 330 PM EDT THU JUN 14 2012
THE MAIN CHALLENGE IN THE LONG TERM IS THE CHANCE FOR THUNDERSTORMS.
THE MID RANGE MODELS ARE SHOWING PERSISTENT HIGH PRESSURE OVER THE
SOUTHEAST OF THE UNITED STATES WITH STORM SYSTEMS FROM THE WEST
BEING PUSHED UP TO THE NORTHWEST OF LOWER MICHIGAN. FEEL THAT LAKE
MICHIGAN MAY ACT AS AN ADDITIONAL BARRIER TO THE WEST OF LOWER
MICHIGAN.
A COUPLE SYSTEMS MIGHT BE ABLE TO SOMEWHAT FLATTEN THE RIDGE AND
BRING THUNDERSTORMS TO THE AREA. THE FIRST WOULD DRAG A COLD FRONT
THROUGH SUNDAY INTO MONDAY. NOT IMPRESSED WITH THE MOISTURE
AVAILABLE WITH THIS FRONT AND THE DYNAMICS REMAIN TO THE NORTHWEST
AND NORTH.
ANOTHER STRONG PUSH IS POSSIBLE LATE TUESDAY INTO WEDNESDAY. THINK
WITH THE BLOCKING HIGH IN PLACE... THIS MAY NOT PASS UNTIL POSSIBLY
WEDNESDAY NIGHT OR THURSDAY. MOST OF THE ENERGY WITH THIS SYSTEM
ALSO PASSES TO THE NORTH.
OVERALL... IT LOOKS WARM WITH ONLY A CHANCE OF THUNDERSTORMS SUNDAY/
SUNDAY NIGHT AND WEDNESDAY/THURSDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1151 PM EDT THU JUN 14 2012
NO CHANGE IN THINKING FROM THE 00Z TAFS TO THE 06Z SET OF TAFS.
VFR CONDITIONS ARE FORECAST TO PREVAIL FROM 06Z TO 06Z. THE ONLY
CLOUD TO IMPACT THE AREA WILL BE CONVECTIVE DEBRIS CLOUDS FROM
UPSTREAM STORMS IN MINN/WISC/IOWA. BASES ON THE CLOUDS SHOULD BE
AT OR ABOVE 15000FT. WINDS WILL BE LIGHT SOUTHEAST TONIGHT AT 5 TO
10 KNOTS...BECOMING SOUTH DURING THE DAY ON FRIDAY AROUND 10
KNOTS.
&&
.MARINE...
ISSUED AT 330 PM EDT THU JUN 14 2012
SOUTHERLY WINDS ANTICIPATED THROUGH SATURDAY GENERALLY IN THE 5 TO
15 KT RANGE. THIS WILL RESULT IN WAVE HEIGHTS OF ONLY AROUND 2 FEET
OR LESS. FOG MAY BECOME AN ISSUE THIS WEEKEND AS AN INCREASINGLY
WARM/HUMID AIRMASS OVERRUNS RELATIVELY COOLER LAKE WATERS.
&&
.HYDROLOGY...
ISSUED AT 330 PM EDT THU JUN 14 2012
NO HYDRO ISSUES ANTICIPATED IN THE SHORT TERM WITH DRY WX TO
CONTINUE THROUGH SATURDAY AFTERNOON. A WEAKENING FRONT WILL BRING A
CHC OF SHOWERS AND TSTORMS SATURDAY NIGHT AND SUNDAY.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...NJJ
SYNOPSIS...LAURENS
SHORT TERM...LAURENS
LONG TERM...63
AVIATION...DUKE
HYDROLOGY...LAURENS
MARINE...LAURENS
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
952 PM EDT THU JUN 14 2012
.SYNOPSIS...
ISSUED AT 330 PM EDT THU JUN 14 2012
AN UPPER LEVEL RIDGE OVER THE LOWER GREAT LAKES REGION WILL CONTINUE
TO PRODUCE PREDOMINANTLY DRY WEATHER THROUGH SATURDAY AFTERNOON. A
FEW LIGHT SHOWERS MAY CLIP NORTH CENTRAL LOWER MICHIGAN TONIGHT
BEFORE DISSIPATING. TEMPERATURES WILL UNDERGO A MODERATING TREND
FRIDAY AND SATURDAY WITH WINDS STAYING OUT OF THE SOUTH. A WEAKENING
FRONTAL BOUNDARY WILL BRING THE NEXT CHANCE OF SHOWERS AND
THUNDERSTORMS SATURDAY NIGHT AND SUNDAY. TEMPERATURES WILL CONTINUE
TO AVERAGE AT LEAST TEN TO FIFTEEN DEGREES ABOVE NORMAL FOR MOST OF
NEXT WEEK.
&&
.UPDATE...
ISSUED AT 952 PM EDT THU JUN 14 2012
WE HAVE GONE AHEAD AND UPDATED THE FCST THIS EVENING TO PULL THE
CHC OF RAIN UP NORTH DURING THE OVERNIGHT HOURS. WE ALSO TOUCHED
UP TEMPS A LITTLE TO ACCOUNT FOR THE LATEST TRENDS.
LATEST REGIONAL RADAR TRENDS INDICATE THAT THE BAND OF PCPN ACROSS
WI AND WRN UPPER MI CONTINUES TO PRETTY MUCH HOLD IN PLACE AND IS
NOT MAKING MUCH PROGRESS TOWARD THE CWFA. MOST MODEL DATA
INDICATES THAT THE LLJ AND ASSOCIATED MOISTURE TRANSPORT LINES UP
WELL WITH THE PCPN...AND KEEPS IT TO OUR WEST AND EVENTUALLY NORTH
TONIGHT. DEEP LAYER THICKNESSES WOULD SUPPORT IT PROPAGATING
TOWARD THE AREA...HOWEVER THE VERY DRY AIR IN PLACE HAS AND IS
EXPECTED TO CONTINUE TO DRY IT UP BEFORE IT MAKES IT HERE.
&&
.SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT)
ISSUED AT 330 PM EDT THU JUN 14 2012
PRIMARY SHORT TERM FCST CHALLENGES INVOLVE DETERMINING HOW WARM IT
WILL BECOME FRIDAY AND SATURDAY AND TO EVALUATE POTENTIAL FOR
SHOWERS AND TSTORMS LATE SATURDAY NIGHT. WE ALSO NEED TO DETERMINE
POTENTIAL FOR ANY SHOWERS FROM A DISSIPATING MCS OVER NORTHERN WI
ATTM TO CLIP OUR AREA OVERNIGHT.
A CONSENSUS OF 12Z SHORT RANGE GUIDANCE SUGGESTS MCS ACTIVITY OVER
NORTHERN WI/SOUTHERN MN WILL STAY TO OUR NW TONIGHT. THAT IS WHERE
STRONG FORCING FROM THE LLJ WILL CONTINUE TO FOCUS CONVECTIVE
DEVELOPMENT/REDEVELOPMENT. IT IS NOT IMPOSSIBLE THAT SOME DYING
SHOWERS OVERNIGHT MAY FLIRT WITH OUR NORTHERNMOST COUNTIES (MAINLY
NORTH OF A LINE FROM LDM TO MOP) AS SUGGESTED BY THE HRRR AND
EXTRAPOLATION OF CURRENT RGNL RADAR TRENDS.
I HAVE ADDED MENTION OF JUST A SLIGHT CHC OF SHOWERS ACROSS OUR
NORTHERNMOST TIER OF COUNTIES LATE TONIGHT TO ACCOUNT FOR THIS. LAPS
SOUNDINGS FROM ACROSS OUR FCST AREA LOOK VERY DRY THOUGH AND I WOULD
EXPECT THE EASTERN WING OF THE DECAYING MCS TO CONTINUE TO WEAKEN
OVER EASTERN WI WHILE NEW CONVECTION TAKES OFF OVER WESTERN WI WHERE
THE ROBUST LLJ FORCING IS. WE WILL MAINLY JUST SEE MID TO HIGH LEVEL
CLOUD BLOWOFF FROM THAT ACTIVITY CONTINUE TO ADVECT IN FROM THE NW
LATE THIS AFTN/TONIGHT.
FAIR/MILDER WX ANTICIPATED FRIDAY WITH THE UPPER RIDGE IN PLACE. MAX
TEMPS TOMORROW WILL REACH THE MID TO UPPER 80S IN CONTINUED
SOUTHERLY FLOW WAA AND WITH H8 TEMPS REACHING 17-18 C BY TOMORROW
AFTN.
HOT CONDITIONS ANTICIPATED FOR SATURDAY WITH SOUTHERLY FLOW WAA
CONTINUING AND H8 TEMPS MODERATING TO 19 TO 20 C. THIS SHOULD RESULT
IN MAX TEMPS REACHING THE UPPER 80S TO LOWER 90S. INCREASING MID TO
HIGH CLOUDS FROM THE WEST SATURDAY AFTERNOON WILL NOT INHIBIT IT
FROM BECOMING HOT BY SATURDAY AFTERNOON.
WILL CARRY LOW CHC POPS FOR SCATTERED SHOWERS/TSTORMS VERY LATE
SATURDAY NIGHT. THIS BASED LARGELY ON 12Z GFS GUIDANCE SHOWING THE
APPROACH OF THE WEAKENING FRONT AND INCREASING 1000-850 MB MOISTURE
TRANSPORT DEVELOPING OVERNIGHT.
HOWEVER IT IS NOTED THAT 12Z NAM GUIDANCE KEEPS IT DRY THRU 12Z
SUNDAY AND THE 00Z/12Z ECMWF ONLY BRINGS A FEW SHOWERS INTO OUR NW
FCST AREA TOWARD DAYBREAK SUNDAY. SO OVERALL IT STILL LOOKS LIKE A
(SLIGHTLY) BETTER CHC FOR A FEW SHOWERS/STORMS WILL HOLD OFF UNTIL
SUNDAY.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 330 PM EDT THU JUN 14 2012
THE MAIN CHALLENGE IN THE LONG TERM IS THE CHANCE FOR THUNDERSTORMS.
THE MID RANGE MODELS ARE SHOWING PERSISTENT HIGH PRESSURE OVER THE
SOUTHEAST OF THE UNITED STATES WITH STORM SYSTEMS FROM THE WEST
BEING PUSHED UP TO THE NORTHWEST OF LOWER MICHIGAN. FEEL THAT LAKE
MICHIGAN MAY ACT AS AN ADDITIONAL BARRIER TO THE WEST OF LOWER
MICHIGAN.
A COUPLE SYSTEMS MIGHT BE ABLE TO SOMEWHAT FLATTEN THE RIDGE AND
BRING THUNDERSTORMS TO THE AREA. THE FIRST WOULD DRAG A COLD FRONT
THROUGH SUNDAY INTO MONDAY. NOT IMPRESSED WITH THE MOISTURE
AVAILABLE WITH THIS FRONT AND THE DYNAMICS REMAIN TO THE NORTHWEST
AND NORTH.
ANOTHER STRONG PUSH IS POSSIBLE LATE TUESDAY INTO WEDNESDAY. THINK
WITH THE BLOCKING HIGH IN PLACE... THIS MAY NOT PASS UNTIL POSSIBLY
WEDNESDAY NIGHT OR THURSDAY. MOST OF THE ENERGY WITH THIS SYSTEM
ALSO PASSES TO THE NORTH.
OVERALL... IT LOOKS WARM WITH ONLY A CHANCE OF THUNDERSTORMS SUNDAY/
SUNDAY NIGHT AND WEDNESDAY/THURSDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 806 PM EDT THU JUN 14 2012
VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD. THE ONLY
CLOUDS THAT ARE EXPECTED ARE HIGH CLOUDS VIA BLOWOFF FROM STORMS
UPSTREAM OVER MINNESOTA...IOWA AND WISCONSIN. BASES SHOULD BE AT
OR ABOVE 15000FT. WINDS WILL BE LIGHT FROM THE SOUTHEAST
TONIGHT...BELOW 10 KNOTS. WINDS AT 1000FT THOUGH WILL BE SOUTH AT
20-30 KNOTS TONIGHT. SOUTH WINDS OF 08-15 KNOTS ARE EXPECTED ON
FRIDAY.
&&
.MARINE...
ISSUED AT 330 PM EDT THU JUN 14 2012
SOUTHERLY WINDS ANTICIPATED THROUGH SATURDAY GENERALLY IN THE 5 TO
15 KT RANGE. THIS WILL RESULT IN WAVE HEIGHTS OF ONLY AROUND 2 FEET
OR LESS. FOG MAY BECOME AN ISSUE THIS WEEKEND AS AN INCREASINGLY
WARM/HUMID AIRMASS OVERRUNS RELATIVELY COOLER LAKE WATERS.
&&
.HYDROLOGY...
ISSUED AT 330 PM EDT THU JUN 14 2012
NO HYDRO ISSUES ANTICIPATED IN THE SHORT TERM WITH DRY WX TO
CONTINUE THROUGH SATURDAY AFTERNOON. A WEAKENING FRONT WILL BRING A
CHC OF SHOWERS AND TSTORMS SATURDAY NIGHT AND SUNDAY.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...NJJ
SYNOPSIS...LAURENS
SHORT TERM...LAURENS
LONG TERM...63
AVIATION...DUKE
HYDROLOGY...LAURENS
MARINE...LAURENS
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
807 PM EDT THU JUN 14 2012
.SYNOPSIS...
ISSUED AT 330 PM EDT THU JUN 14 2012
AN UPPER LEVEL RIDGE OVER THE LOWER GREAT LAKES REGION WILL CONTINUE
TO PRODUCE PREDOMINANTLY DRY WEATHER THROUGH SATURDAY AFTERNOON. A
FEW LIGHT SHOWERS MAY CLIP NORTH CENTRAL LOWER MICHIGAN TONIGHT
BEFORE DISSIPATING. TEMPERATURES WILL UNDERGO A MODERATING TREND
FRIDAY AND SATURDAY WITH WINDS STAYING OUT OF THE SOUTH. A WEAKENING
FRONTAL BOUNDARY WILL BRING THE NEXT CHANCE OF SHOWERS AND
THUNDERSTORMS SATURDAY NIGHT AND SUNDAY. TEMPERATURES WILL CONTINUE
TO AVERAGE AT LEAST TEN TO FIFTEEN DEGREES ABOVE NORMAL FOR MOST OF
NEXT WEEK.
&&
.SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT)
ISSUED AT 330 PM EDT THU JUN 14 2012
PRIMARY SHORT TERM FCST CHALLENGES INVOLVE DETERMINING HOW WARM IT
WILL BECOME FRIDAY AND SATURDAY AND TO EVALUATE POTENTIAL FOR
SHOWERS AND TSTORMS LATE SATURDAY NIGHT. WE ALSO NEED TO DETERMINE
POTENTIAL FOR ANY SHOWERS FROM A DISSIPATING MCS OVER NORTHERN WI
ATTM TO CLIP OUR AREA OVERNIGHT.
A CONSENSUS OF 12Z SHORT RANGE GUIDANCE SUGGESTS MCS ACTIVITY OVER
NORTHERN WI/SOUTHERN MN WILL STAY TO OUR NW TONIGHT. THAT IS WHERE
STRONG FORCING FROM THE LLJ WILL CONTINUE TO FOCUS CONVECTIVE
DEVELOPMENT/REDEVELOPMENT. IT IS NOT IMPOSSIBLE THAT SOME DYING
SHOWERS OVERNIGHT MAY FLIRT WITH OUR NORTHERNMOST COUNTIES (MAINLY
NORTH OF A LINE FROM LDM TO MOP) AS SUGGESTED BY THE HRRR AND
EXTRAPOLATION OF CURRENT RGNL RADAR TRENDS.
I HAVE ADDED MENTION OF JUST A SLIGHT CHC OF SHOWERS ACROSS OUR
NORTHERNMOST TIER OF COUNTIES LATE TONIGHT TO ACCOUNT FOR THIS. LAPS
SOUNDINGS FROM ACROSS OUR FCST AREA LOOK VERY DRY THOUGH AND I WOULD
EXPECT THE EASTERN WING OF THE DECAYING MCS TO CONTINUE TO WEAKEN
OVER EASTERN WI WHILE NEW CONVECTION TAKES OFF OVER WESTERN WI WHERE
THE ROBUST LLJ FORCING IS. WE WILL MAINLY JUST SEE MID TO HIGH LEVEL
CLOUD BLOWOFF FROM THAT ACTIVITY CONTINUE TO ADVECT IN FROM THE NW
LATE THIS AFTN/TONIGHT.
FAIR/MILDER WX ANTICIPATED FRIDAY WITH THE UPPER RIDGE IN PLACE. MAX
TEMPS TOMORROW WILL REACH THE MID TO UPPER 80S IN CONTINUED
SOUTHERLY FLOW WAA AND WITH H8 TEMPS REACHING 17-18 C BY TOMORROW
AFTN.
HOT CONDITIONS ANTICIPATED FOR SATURDAY WITH SOUTHERLY FLOW WAA
CONTINUING AND H8 TEMPS MODERATING TO 19 TO 20 C. THIS SHOULD RESULT
IN MAX TEMPS REACHING THE UPPER 80S TO LOWER 90S. INCREASING MID TO
HIGH CLOUDS FROM THE WEST SATURDAY AFTERNOON WILL NOT INHIBIT IT
FROM BECOMING HOT BY SATURDAY AFTERNOON.
WILL CARRY LOW CHC POPS FOR SCATTERED SHOWERS/TSTORMS VERY LATE
SATURDAY NIGHT. THIS BASED LARGELY ON 12Z GFS GUIDANCE SHOWING THE
APPROACH OF THE WEAKENING FRONT AND INCREASING 1000-850 MB MOISTURE
TRANSPORT DEVELOPING OVERNIGHT.
HOWEVER IT IS NOTED THAT 12Z NAM GUIDANCE KEEPS IT DRY THRU 12Z
SUNDAY AND THE 00Z/12Z ECMWF ONLY BRINGS A FEW SHOWERS INTO OUR NW
FCST AREA TOWARD DAYBREAK SUNDAY. SO OVERALL IT STILL LOOKS LIKE A
(SLIGHTLY) BETTER CHC FOR A FEW SHOWERS/STORMS WILL HOLD OFF UNTIL
SUNDAY.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 330 PM EDT THU JUN 14 2012
THE MAIN CHALLENGE IN THE LONG TERM IS THE CHANCE FOR THUNDERSTORMS.
THE MID RANGE MODELS ARE SHOWING PERSISTENT HIGH PRESSURE OVER THE
SOUTHEAST OF THE UNITED STATES WITH STORM SYSTEMS FROM THE WEST
BEING PUSHED UP TO THE NORTHWEST OF LOWER MICHIGAN. FEEL THAT LAKE
MICHIGAN MAY ACT AS AN ADDITIONAL BARRIER TO THE WEST OF LOWER
MICHIGAN.
A COUPLE SYSTEMS MIGHT BE ABLE TO SOMEWHAT FLATTEN THE RIDGE AND
BRING THUNDERSTORMS TO THE AREA. THE FIRST WOULD DRAG A COLD FRONT
THROUGH SUNDAY INTO MONDAY. NOT IMPRESSED WITH THE MOISTURE
AVAILABLE WITH THIS FRONT AND THE DYNAMICS REMAIN TO THE NORTHWEST
AND NORTH.
ANOTHER STRONG PUSH IS POSSIBLE LATE TUESDAY INTO WEDNESDAY. THINK
WITH THE BLOCKING HIGH IN PLACE... THIS MAY NOT PASS UNTIL POSSIBLY
WEDNESDAY NIGHT OR THURSDAY. MOST OF THE ENERGY WITH THIS SYSTEM
ALSO PASSES TO THE NORTH.
OVERALL... IT LOOKS WARM WITH ONLY A CHANCE OF THUNDERSTORMS SUNDAY/
SUNDAY NIGHT AND WEDNESDAY/THURSDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 806 PM EDT THU JUN 14 2012
VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD. THE ONLY
CLOUDS THAT ARE EXPECTED ARE HIGH CLOUDS VIA BLOWOFF FROM STORMS
UPSTREAM OVER MINNESOTA...IOWA AND WISCONSIN. BASES SHOULD BE AT
OR ABOVE 15000FT. WINDS WILL BE LIGHT FROM THE SOUTHEAST
TONIGHT...BELOW 10 KNOTS. WINDS AT 1000FT THOUGH WILL BE SOUTH AT
20-30 KNOTS TONIGHT. SOUTH WINDS OF 08-15 KNOTS ARE EXPECTED ON
FRIDAY.
&&
.MARINE...
ISSUED AT 330 PM EDT THU JUN 14 2012
SOUTHERLY WINDS ANTICIPATED THROUGH SATURDAY GENERALLY IN THE 5 TO
15 KT RANGE. THIS WILL RESULT IN WAVE HEIGHTS OF ONLY AROUND 2 FEET
OR LESS. FOG MAY BECOME AN ISSUE THIS WEEKEND AS AN INCREASINGLY
WARM/HUMID AIRMASS OVERRUNS RELATIVELY COOLER LAKE WATERS.
&&
.HYDROLOGY...
ISSUED AT 330 PM EDT THU JUN 14 2012
NO HYDRO ISSUES ANTICIPATED IN THE SHORT TERM WITH DRY WX TO
CONTINUE THROUGH SATURDAY AFTERNOON. A WEAKENING FRONT WILL BRING A
CHC OF SHOWERS AND TSTORMS SATURDAY NIGHT AND SUNDAY.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS...LAURENS
SHORT TERM...LAURENS
LONG TERM...63
AVIATION...DUKE
HYDROLOGY...LAURENS
MARINE...LAURENS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
135 AM EDT WED JUN 13 2012
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 325 PM EDT TUE JUN 12 2012
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW PROGRESSIVE UPR
TROF EXTENDING FM HUDSON BAY INTO THE GRT LKS MOVING E IN ADVANCE OF
UPR RDG OVER WRN CANADA. SHRTWV EMBEDDED WITHIN THIS TROF BROUGHT
LOTS OF CLDS AND SOME -SHRA TO MAINLY THE NRN TIER INTO EARLY
AFTN... BUT TREND THIS AFTN HAS BEEN FOR MORE SUNSHINE AS DNVA/
LARGER SCALE QVECTOR DVGC/MORE ACYC FLOW AND DRIER AIR SHOWN ON THE
12Z INL RAOB IS FOLLOWING IN THE WAKE OF THAT DISTURBANCE IN ADVANCE
OF SFC HI PRES CENTERED OVER SE SDAKOTA. SKIES ARE MOCLR FM THE HI
CENTER STRETCHING TOWARD LK WINNIPEG...WHERE THE 12Z RAOB AT THE PAS
IN MANITOBA SHOWS A PWAT OF 0.28 INCH. SFC DEWPTS THIS AFTN HAVE
MIXED OUT INTO THE LO-MID 30S IN THIS UPSTREAM AIRMASS. MORE CLDS
ARE PRESENT A BIT FARTHER W IN THE NRN PLAINS IN THE RETURN SW FLOW
ARND THE SFC HI AND IN ADVANCE OF SHRTWV TRACKING E ACRS
WYOMING/MONTANA. 12Z BIS RAOB SHOWS MORE MSTR/PWAT OF 0.70 INCH NEAR
THE WAD CLD BAND.
MAIN FCST CONCERNS IN THE SHORT TERM REVOLVE ARND CLRG TRENDS THIS
AFTN AND THEN TEMPS/POTENTIAL FOR FROST TNGT.
TNGT...SFC HI PRES IS FCST TO MOVE E AND TO OVER NRN LWR MI BY 12Z
WED. EXPECT ANY LINGERING CLDS TO DSPT LATE THIS AFTN/EARLY THIS
EVNG WITH THE ARRIVAL OF MORE ACYC FLOW AND WARMER/DRIER AIR AT
H925. STRONGER WSW FLOW ARND SFC HI IS FCST TO DVLP OVER THE NW HALF
OF THE CWA AFT 06Z...WITH PWAT RISING AS THIS FLOW TAPS MORE MSTR
SHOWN ON THE 12Z BIS RAOB. MOST SUSTAINED CONDITIONS FOR RADIATIONAL
COOLING LOOK TO BE OVER THE SCNTRL AND E...WHERE THE GRADIENT FLOW
WL REMAIN WEAKER/PWAT LOWER AND UNDER 0.5 INCH THRU 12Z WED. OPTED
TO EXTEND GOING FROST ADVY NEAR THE WI BORDER TO INCLUDE MOST OF THE
CWA FROM BARAGA TO THE E...WITH MIN TEMPS CLOSER TO THE LOWER END OF
GUIDANCE IN THESE AREAS PER OBSVD MIXING OF DEWPTS UPSTREAM.
WED...AS SFC HI PRES DRIFTS SLOWLY E ACRS LK HURON...STRONGER SW
FLOW WL DVLP OVER THE ENTIRE CWA. WITH APRCH OF DISTURBANCE NOW
MOVING THRU THE NRN PLAINS AND SOME MSTR RETURN...EXPECT AT LEAST
SOME CLDS TO INVADE MAINLY THE WRN ZNS IN THE AFTN. ALTHOUGH THE GFS
GENERATES SOME PCPN OVER THE FAR W LATE IN THE DAY...PREFER TO
FOLLOW THE DRY 12Z NAM/CNDN/LOCAL WRF-ARW DUE TO VERY DRY NATURE OF
LLVL AIRMASS. MIXING TO H8 ON NAM FCST SDNGS YIELDS HI TEMPS
REBOUNDING TO 70 TO 75 AWAY FM LK MODERATION.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 325 PM EDT TUE JUN 12 2012
THE WEAK HIGH PRESSURE RIDGE IN PLACE FOR WEDNESDAY WILL SLIDE
EASTWARD AS A TROUGH OVER THE CANADIAN PRAIRIE DIGS DOWN INTO THE
NORTHERN PLAINS. MODELS AGREE THAT A SHORTWAVE WILL BE APPROACHING
WESTERN UPPER MICHIGAN BY 00Z THURSDAY...THOUGH THERE SEEMS TO BE
DIFFERENCES WITH HOW STRONG IT WILL BE. THE GEM/ECMWF SEEM TO AGREE
ON A WEAKER SOLUTION...WHILE THE GFS DEVELOPS A SMALL TROUGH. THE
GFS ALSO AMPLIFIES THE EXITING RIDGE MUCH MORE THAN THE OTHER
MODELS. WILL STICK WITH A BLEND MORE SIMILAR TO THE GEM/ECMWF FOR
NOW GIVEN THEIR AGREEMENT...THOUGH CONFIDENCE IS NOT VERY HIGH. THIS
KEEPS MOST OF THE PRECIPITATION THAT WILL OCCUR WITH THIS SHORTWAVE
OVER WESTERN LAKE SUPERIOR AND THE WEST HALF OF THE CWA. WILL KEEP
LOW CHANCE POPS OVER THESE AREAS TO ACCOUNT FOR UNCERTAINTY DURING
THE DAY ON THURSDAY. MODEL SOUNDINGS SUGGEST MIXING TO AROUND
850MB...WHICH PUTS HIGHS IN THE 70S AND PERHAPS LOW 80S. DESPITE
INCOMING CLOUD COVER WITH THE SHORTWAVE...EXPECT THE WARMEST
TEMPERATURES TO BE OUT WEST WITH THE HIGHEST 850MB TEMPS OF AROUND
13C. WITH SKIES MOSTLY SUNNY OUT EAST...EXPECT MIXING TO BRING
RELATIVE HUMIDITY DOWN INTO THE 30 PERCENT RANGE. WITH THE STRONGER
PRESSURE GRADIENT ASSOCIATED WITH THE LOW PRESSURE SYSTEM...EXPECT
GUSTY SOUTHERLY TO SOUTHEASTERLY WINDS ACROSS MUCH OF THE
AREA...MAINLY NORTH CENTRAL AND OVER LAKE SUPERIOR. HIGHEST GUSTS
ARE EXPECTED TO BE AROUND 25 KNOTS.
FRIDAY THE TROUGH WILL SWING JUST NORTH OF LAKE SUPERIOR...REACHING
HUDSON BAY BY 00Z SATURDAY. MODELS SEEM TO BE IN FAIRLY GOOD
AGREEMENT ON THE AMOUNT OF QPF ASSOCIATED WITH THE PASSING FRONT
ACROSS WEST AND CENTRAL UPPER MICHIGAN...WITH AROUND 0.25-0.50 INCH
IMPACTING THE AREA. THE NAM BRINGS THE FRONT ALL THE WAY THROUGH THE
CWA...BRINGING 0.25 INCH TO THE EASTERN AREAS. THE ECMWF/GEM/GFS
TAKE THE BEST UPPER LEVEL FORCING NORTHWARD /PER 850-500MB QVECTOR
CONVERGENCE/ AND THEREFORE KEEP MUCH OF THE EASTERN CWA DRY. THERE
ARE ALSO DIFFERENCES IN TIMING OF PRECIPITATION...SO HAVE LOWERED
CONFIDENCE IN PUTTING SPECIFICS INTO THE FORECAST. KEPT THE BEST
CHANCES OVER LAKE SUPERIOR AND ACROSS THE WEST AND CENTRAL. MU/ML
CAPE VALUES THURSDAY NIGHT INTO FRIDAY AFTERNOON RANGE FROM AROUND
200-1000 J/KG...SO KEPT THUNDER CHANCES IN. WITH PRESSURE GRADIENT
REMAINING TIGHT...WINDS WILL CONTINUE TO GUST INTO THE 20-25 KNOT
RANGE THROUGH FRIDAY EVENING.
FOR THE EXTENDED /THE WEEKEND INTO TUESDAY/...
FOR THE MOST PART...IT SEEMS THROUGH THE WEEKEND A RIDGE WILL CENTER
ITSELF OVER LOWER MICHIGAN...AND SHORTWAVES WILL RIDE AROUND THE
IT BRINGING CHANCES OF PRECIPITATION. FOR THE FIRST PART OF THE
WORK WEEK...A STRONGER LOW PRESSURE TROUGH WILL SWING INTO THE
NORTHERN PLAINS AND BRING ADDITIONAL PRECIPITATION/THUNDERSTORMS TO
MUCH OF THE CWA. HOWEVER...MODELS DIFFER ON TIMING AND PLACEMENT OF
FEATURES. THE GFS/GEM BRING A STRONGER RIDGE UP FROM THE
PLAINS...KEEPING MUCH OF THE PRECIPITATION ASSOCIATED WITH A SECOND
TROUGH/SHORTWAVE CONFINED TO THE WESTERN CWA OR NOT IN THE UPPER
PENINSULA AT ALL. THE GFS EVENTUALLY DEVELOPS THE TROUGH INTO A
CLOSED LOW...AND THEN MOVES THE PRECIPITATION THROUGH ON MONDAY. THE
ECMWF KEEPS THE RIDGE FURTHER SOUTH AND EAST...AND BRINGS A MUCH
MORE POTENT SHORTWAVE INTO UPPER MICHIGAN SATURDAY MORNING INTO
MONDAY. WITH SUCH A VARIANCE IN SOLUTIONS...DO NOT FEEL CONFIDENT
BUMPING UP ANY POPS. WILL KEEP THE MENTION OF THUNDER AS MODELS SEEM
TO BRING IN A DECENT AMOUNT OF INSTABILITY THROUGH THE WEEKEND. AS
FOR HIGH TEMPERATURES...850MB TEMPS LOOK TO BE IN THE 16-18C
RANGE...SO WILL KEEP FORECASTED HIGHS IN THE UPPER 70S TO THE MID
80S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 132 AM EDT WED JUN 13 2012
HIGH PRESSURE TO INFLUENCE THE WEATHER THROUGH THE FORECAST PERIOD
WITH VFR CONDITIONS PREVAILING. WINDS TO STAY LIGHT OVERNIGHT UNTIL
PICKING UP FROM THE SW AFTER SUNRISE AS SFC HIGH SHIFTS EAST. SOME
GUSTS UP TO 20 KTS EXPECTED OVER KIWD WHERE GRADIENT TO BE A BIT
TIGHTER. MID CLOUDS TO INCREASE AND WINDS BACK TO THE SOUTH TO
SOUTHEAST LATE IN THE FORECAST AS AN APPROACHING LOW PRESSURE SYSTEM
MOVES THROUGH THE NORTHERN PLAINS. THIS FEATURE COULD BRING AN
ISOLATED SHOWER OR THUNDERSTORM TO THE KIWD VICINITY AFTER 0Z
THURSDAY.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 325 PM EDT TUE JUN 12 2012
EXPECT NW WINDS UP TO 25-30 KTS INTO THIS EVENING OVER THE E TO
DIMINISH OVERNIGHT WITH THE ARRIVAL OF A HI PRES RIDGE. THESE LIGHT
WINDS WILL PERSIST INTO WED NIGHT AS THE HI REMAINS DOMINANT. THEN A
STRONGER S WIND UP TO 25 KTS WILL IMPACT MAINLY THE NCENTRAL AND E
PART OF THE LAKE ON THU/FRI UNDER A TIGHTER PRES GRADIENT BETWEEN
THE HI DEPARTING TO THE E AND A LO PRES TROF APPROACHING FROM THE W.
THEN LIGHTER WINDS WILL PREVAIL AGAIN THIS COMING WEEKEND WITH A
WEAKER PRES GRADIENT FORECAST TO DOMINATE THE UPPER LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
FROST ADVISORY UNTIL 7 AM EDT /6 AM CDT/ THIS MORNING FOR MIZ002-
004>007-009>014-084-085.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...MCB
AVIATION...RJT
MARINE...KC
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
642 PM CDT Thu Jun 14 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...
Storms along front in southeast Nebraska and west central Kansas will
continue eastward then more southward over the next several hours.
Depending on when the storms turn south...the timing into the
terminals is somewhat uncertain. Based on current movement an how
much of a cold pool is generating by the storms...along with model
guidance...best estimate is around 07Z and KSTJ and then an hour
later into KMCI and another hour into KMKC. It is possible that the
storms will ride along the border of Kansas and Missouri and not have
much influence on terminals...but will monitor closely over the next
few hours. Storms strength is also in question as less instability
and shear are forecast over eastern Kansas and northern Missouri.
Again...will monitor for changes. One thing is more certain...the
dynamics in the upper atmosphere are much stronger well to the north
in to Minnesota and western Great Lakes...so that will also limit the
severity of the storms. Wind is the main threat with the storms along
with possible solid line formation...as the freezing level is fairly
high at around 14K ft or so. Expecting around 30 kts in the vicinity
of storms but will continue to monitor the upstream activity as well
to see if that will be high enough for any storms that make it over
the terminals. The front will not likely make much progress so
keeping VCTS after any late night convection is reasonable. Adolphson
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
WFO EAX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
102 PM CDT WED JUN 13 2012
.AVIATION...18Z TAFS FOR KOMA...KLNK AND KOFK. VFR TO MVFR
CONDITIONS THROUGH THE FORECAST PERIOD. THERE IS A SLIGHT CHANCE
OF -TSRA PRIMARILY AT KOFK IN THE 03Z TO 06Z TIME FRAME. OTHERWISE
THE WEATHER FEATURE WILL BE THE BREEZY SOUTHEAST WINDS 10 TO 15
KTS WITH GUSTS 25 TO 28KTS UNTIL 01Z. COLD FRONT WILL APPROACH THE
FORECAST AREA PRODUCING THREAT OF TSRA...ESPECIALLY KOFK
AREA...BY THE END OF THE FORECAST PERIOD.
&&
.PREV DISCUSSION... /ISSUED 614 AM CDT WED JUN 13 2012/
88D MOSAIC THIS MORNING SHOWING NARROW LINE OF BOWED-OUT ELEVATED
CONVECTION DRIVING EWD INTO ERN SD/ERN NEB. ACTIVITY WAS OCCURRING
WITHIN AREA OF STRONG LAYER DIFFERENTIAL DIVG/850MB WAA WITH A
LLVL MOIST FEED UP THRU THE CNTRL PLAINS. HRRR AND RAP SUGGESTING
ACTIVITY SHOULD BE OUT OF THE CWA SOMETIME AROUND RUSH HOUR.
ON THE WHOLE...MODELS CONTINUE TO BE IN REASONABLY GOOD AGREEMENT
THAT LARGE SCALE FLOW OVER THE NEXT WEEK WILL TRANSITION FROM NEAR
ZONAL OVER THE CONUS TO A RELATIVELY STAGNANT SITUATION WITH A BROAD
TROF COVERING THE WRN CONUS AND A RIDGE TO THE EAST. ALSO GOOD
AGREEMENT THAT BULK OF ACCUMULATING PCPN WILL GENERALLY OCCUR OVER
THE UPPER MIDWEST...ERN DAKOTAS...WRN IA...ERN NEB THRU DAY 7. ALL
THIS IN PART TO A PROLONGED MID LYR BNDRY ORIENTED PARALLEL TO SW-NE
FLOW ALOFT WITH SUSTAINED LLVL MOISTURE TO FEED ON PER MOISTURE
TRANSPORT PROGS. LIFTING MECHANISM THOUGH WILL BE MEANDERING SOMEWHAT
DURING THIS TIME...MAKING IT IMPOSSIBLE TO PIN DOWN POPS WITHIN THE
CWA. THUS...BECAUSE OF UNCERTAINTIES WILL OPT TO JUST BLANKET THE
AREA WITH SMALL POPS.
DEE
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
99/99
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
614 AM CDT WED JUN 13 2012
.AVIATION...12Z TAFS FOR KOMA...KLNK AND KOFK. VFR CONDITIONS
THROUGH THE PERIOD. SOUTHEAST WINDS AROUND 12 KNOTS DO INCREASE
WITH GUSTS UP TO 25 TO 28 KTS BY 15-17Z AND SHOULD CONTINUE UNTIL
ABOUT 14/01Z.
&&
.PREV DISCUSSION...
88D MOSAIC THIS MORNING SHOWING NARROW LINE OF BOWED-OUT ELEVATED
CONVECTION DRIVING EWD INTO ERN SD/ERN NEB. ACTIVITY WAS OCCURRING
WITHIN AREA OF STRONG LAYER DIFFERENTIAL DIVG/850MB WAA WITH A LLVL
MOIST FEED UP THRU THE CNTRL PLAINS. HRRR AND RAP SUGGESTING ACTIVITY
SHOULD BE OUT OF THE CWA SOMETIME AROUND RUSH HOUR.
ON THE WHOLE...MODELS CONTINUE TO BE IN REASONABLY GOOD AGREEMENT
THAT LARGE SCALE FLOW OVER THE NEXT WEEK WILL TRANSITION FROM NEAR
ZONAL OVER THE CONUS TO A RELATIVELY STAGNANT SITUATION WITH A BROAD
TROF COVERING THE WRN CONUS AND A RIDGE TO THE EAST. ALSO GOOD
AGREEMENT THAT BULK OF ACCUMULATING PCPN WILL GENERALLY OCCUR OVER
THE UPPER MIDWEST...ERN DAKOTAS...WRN IA...ERN NEB THRU DAY 7. ALL
THIS IN PART TO A PROLONGED MID LYR BNDRY ORIENTED PARALLEL TO SW-NE
FLOW ALOFT WITH SUSTAINED LLVL MOISTURE TO FEED ON PER MOISTURE
TRANSPORT PROGS. LIFTING MECHANISM THOUGH WILL BE MEANDERING SOMEWHAT
DURING THIS TIME...MAKING IT IMPOSSIBLE TO PIN DOWN POPS WITHIN THE
CWA. THUS...BECAUSE OF UNCERTAINTIES WILL OPT TO JUST BLANKET THE
AREA WITH SMALL POPS.
DEE
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
446 AM EDT WED JUN 13 2012
.SYNOPSIS...
COOLER AND DRIER AIR WILL MOVE IN AS HIGH PRESSURE BUILDS OVER
THE GREAT LAKES. DRY CONDITIONS ARE EXPECTED THROUGH THE COMING
WEEKEND. NEAR NORMAL TEMPERATURES THURSDAY AND FRIDAY...WILL EDGE
UPWARD BY EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
430 AM UPDATE...
COLD FRONT...WHICH WAS WELL MARKED BY BAND OF LIGHT
SHOWERS...JUST PASSED THROUGH MONTICELLO AND IS CLEARING THE AREA.
HOWEVER...NAM AND RUC ARE IN AGREEMENT WITH UPSTREAM SATELLITE
IMAGERY...THAT A TEMPORARY SCT TO BKN STRATOCUMULUS DECK WILL MOVE
BACK IN AS FINAL VORTICITY LOBE CARRIES THROUGH FROM 11Z NW TO 15Z
SE. THESE CLOUDS WILL THEN MIX OUT WITH THE MUCH DRIER AIR MASS
ADVECTING IN...ALONG WITH HIGH PRESSURE BUILDING IN FROM WESTERN
GREAT LAKES REGION. HIGH TEMPERATURES IN THE WAKE OF THE COLD
FRONT WILL BE SLIGHTLY BELOW NORMAL...AND A FRESH NORTHERLY
BREEZE WITH GUSTS OF 15 TO 25 MPH WILL HELP TO MAKE THE COOLER AIR
MASS MORE APPARENT.
MAINLY CLEAR NIGHT TONIGHT...THOUGH SOME UNCERTAINTY AS TO WHETHER
AT LEAST A FEW CLOUDS WILL TRY TO HANG ON NEAR POCONOS-
CATSKILLS...WHERE WEAK LOW LEVEL CONVERGENCE WILL COINCIDE WITH
SOME MOISTURE AROUND 850MB. EITHER WAY...LOOKING AT A COOL NIGHT
WITH LOWS IN THE MID 40S TO LOW 50S FOR MOST OF THE AREA...THANKS
TO LOW DEWPOINTS AND RADIATIONAL COOLING...WITH A FEW OF THE
TYPICAL COLDER SPOTS EVEN GETTING INTO LOWER 40S. ALSO APPEARS TO
BE A GOOD SET UP FOR PATCHY FOG IN SOME RIVER VALLEYS SUCH AS IN
THE ELMIRA AREA.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
A SLOW UL RIDGING PROCESS WILL BEGIN THIS PERIOD, WITH A STRONG
SURFACE HIGH SETTING UP ALONG THE EASTERN SEABOARD. THIS WILL LEAD
TO A QUIET WEATHER PATTERN, WITH DAYTIME HIGHS PUSHING INTO THE
MIDDLE OR UPPER 70S. OVERNIGHT LOWS WILL DIP INTO THE UPPER 40S
AND LOWER 50S.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
UL RIDGING WILL CONTINUE, LEADING TO A WARMING TREND. THE WEEKEND
WILL BEGIN WITH TEMPERATURES REACHING INTO THE UPPER 70S AND LOWER
80S DURING THE AFTERNOON. BY EARLY NEXT WEEK, THE BUILDING
THICKNESS PATTERN WILL PUSH AFTERNOON MAXES INTO THE LOWER AND
MIDDLE 80S.
THE PATTERN APPEARS DRY, THOUGH WE DO ACCOUNT FOR SOME UNCERTAINTY
WITH SLIGHT CHANCE POPS AT THE END OF THE PERIOD WHEN DEW POINTS
CLIMB BACK TOWARD 60F.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
09Z UPDATE...
FRONT HAS MOVED EAST OF THE AREA AS OF 09Z. LOOKING AT MAINLY VFR
BEHIND THE FRONT AREAWIDE...AT LEAST INITIALLY. A FINAL WEAK UPPER
DISTURBANCE BEHIND THE FRONT...AS CAN NOW BE SEEN BY STRATOCUMULUS
UPSTREAM OVER ONTARIO...WILL ALLOW MVFR OR LOW END VFR DECK TO
DEVELOP FOR MOST TERMINALS DURING THE 11Z-15Z WINDOW /SEE TAFS FOR
TIMING DETAILS/. BECAUSE OF DRYNESS OF INCOMING AIR MASS...NOT
EXPECTING IFR DESPITE A COUPLE HILLTOP MODEL SOUNDINGS SUGGESTING
IT DURING THAT TIME. AFTER THE EARLY MORNING MVFR...STRATOCUMULUS
LIFTS AND MIXES OUT COURTESY OF VERY DRY AIR MASS. NORTHERLY WINDS
GUSTING 15-20 KTS DURING THE DAY WITH VFR...THEN DROPPING TO LESS
THAN 10 KTS WITH DECOUPLING THIS EVENING.
OUTLOOK...
LATE WED NIGHT TO SUNDAY...MAINLY VFR. POSSIBLY EARLY MORNING
IFR/MVFR VALLEY FOG...MAINLY KELM.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MDP
SHORT TERM...DJP
LONG TERM...DJP
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
241 AM EDT WED JUN 13 2012
.SYNOPSIS...
IN THE WAKE OF AN OVERNIGHT COLD FRONT...COOLER AND DRIER AIR WILL
MOVE IN AS HIGH PRESSURE BUILDS OVER THE GREAT LAKES. MORNING
CLOUDS WILL BREAK UP DURING THE DAY...FOLLOWED BY A COOL NIGHT.
DRY CONDITIONS ARE EXPECTED THROUGH THE COMING WEEKEND...WITH INITIALLY
NEAR NORMAL TEMPERATURES EDGING UPWARD BY EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
2 AM UPDATE...
COLD FRONT...WELL MARKED BY BAND OF LIGHT SHOWERS...STRETCHES FROM
ONEONTA THROUGH WALTON THROUGH SCRANTON AND WILKES-BARRE JUST
BEFORE 2 AM. IT WILL FINISH CLEARING THE AREA BEFORE DAWN.
HOWEVER...NAM AND RUC ARE IN AGREEMENT WITH UPSTREAM
OBSERVATIONS...THAT A TEMPORARY STRATOCUMULUS DECK WILL MOVE BACK
IN AS FINAL VORTICITY LOBE CARRIES THROUGH FROM 10Z NW TO 15Z SE.
THESE CLOUDS WILL THEN MIX OUT WITH THE MUCH DRIER AIR MASS
ADVECTING IN...ALONG WITH HIGH PRESSURE BUILDING IN FROM WESTERN
GREAT LAKES REGION.
MAINLY CLEAR NIGHT TONIGHT...THOUGH SOME UNCERTAINTY AS TO WHETHER
AT LEAST A FEW CLOUDS WILL TRY TO HANG ON NEAR POCONOS-
CATSKILLS...WHERE WEAK LOW LEVEL CONVERGENCE WILL COINCIDE WITH
SOME MOISTURE AROUND 850MB. EITHER WAY...LOOKING AT A COOL NIGHT
WITH LOWS IN THE MID 40S TO LOW 50S FOR MOST OF THE AREA...THANKS
TO LOW DEWPOINTS AND RADIATIONAL COOLING...AND LIGHT NORTHEAST
FLOW.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
A SLOW UL RIDGING PROCESS WILL BEGIN THIS PERIOD, WITH A STRONG
SURFACE HIGH SETTING UP ALONG THE EASTERN SEABOARD. THIS WILL LEAD
TO A QUIET WEATHER PATTERN, WITH DAYTIME HIGHS PUSHING INTO THE
MIDDLE OR UPPER 70S. OVERNIGHT LOWS WILL DIP INTO THE UPPER 40S
AND LOWER 50S.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
UL RIDGING WILL CONTINUE, LEADING TO A WARMING TREND. THE WEEKEND
WILL BEGIN WITH TEMPERATURES REACHING INTO THE UPPER 70S AND LOWER
80S DURING THE AFTERNOON. BY EARLY NEXT WEEK, THE BUILDING
THICKNESS PATTERN WILL PUSH AFTERNOON MAXES INTO THE LOWER AND
MIDDLE 80S.
THE PATTERN APPEARS DRY, THOUGH WE DO ACCOUNT FOR SOME UNCERTAINTY
WITH SLIGHT CHANCE POPS AT THE END OF THE PERIOD WHEN DEW POINTS
CLIMB BACK TOWARD 60F.
&&
.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
06Z UPDATE...
FRONT MOVING INTO KAVP AT 06Z...AFTER HAVING CLEARED THE REMAINDER
OF THE AREA BETWEEN 00Z-06Z. MODELS CONTINUE TO UNDERESTIMATE
DRYNESS OF AIRMASS BEHIND THE FRONT...WITH GUIDANCE AND LAMP
PROBABILITIES SUGGESTING MVFR OR EVEN IFR FOR MOST SITES THROUGH
REMAINDER OF THE NIGHT. INSTEAD...OTHER THAN POSSIBLE BRIEF IFR
CIG/VIS WITH NARROW SHOWER BAND IMMEDIATELY ALONG FRONT FOR
KAVP 06Z-07Z...LOOKING AT MAINLY VFR BEHIND THE FRONT AREAWIDE...AT
LEAST INITIALLY. A FINAL WEAK UPPER DISTURBANCE BEHIND THE
FRONT...AS CAN NOW BE SEEN BY STRATOCUMULUS UPSTREAM OVER
ONTARIO...WILL ALLOW MVFR DECK TO DEVELOP FOR MOST TERMINALS
DURING THE 10Z-14Z WINDOW /SEE TAFS FOR TIMING DETAILS/. BECAUSE
OF DRYNESS OF INCOMING AIR MASS...NOT EXPECTING IFR DESPITE A COUPLE
HILLTOP MODEL SOUNDINGS SUGGESTING IT DURING THAT TIME. AFTER THE
EARLY MORNING MVFR...STRATOCUMULUS LIFTS AND MIXES OUT COURTESY OF
VERY DRY AIR MASS. NORTHERLY WINDS GUSTING 15-20 KTS DURING THE
DAY WITH VFR...THEN DROPPING TO LESS THAN 10 KTS WITH DECOUPLING
THIS EVENING.
OUTLOOK...
LATE WED NIGHT TO SUNDAY...MAINLY VFR. POSSIBLY EARLY MORNING
IFR/MVFR VALLEY FOG AT KELM.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MDP
SHORT TERM...DJP
LONG TERM...DJP
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
204 AM EDT WED JUN 13 2012
.SYNOPSIS...
IN THE WAKE OF AN OVERNIGHT COLD FRONT...COOLER AND DRIER AIR WILL
MOVE IN AS HIGH PRESSURE BUILDS OVER THE GREAT LAKES. MORNING
CLOUDS WILL BREAK UP DURING THE DAY...FOLLOWED BY A COOL NIGHT.
DRY CONDITIONS ARE EXPECTED THROUGH THE COMING WEEKEND...WITH INITIALLY
NEAR NORMAL TEMPERATURES EDGING UPWARD BY EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
2 AM UPDATE...
COLD FRONT...WELL MARKED BY BAND OF LIGHT SHOWERS...STRETCHES FROM
ONEONTA THROUGH WALTON THROUGH SCRANTON AND WILKES-BARRE JUST
BEFORE 2 AM. IT WILL FINISH CLEARING THE AREA BEFORE DAWN.
HOWEVER...NAM AND RUC ARE IN AGREEMENT WITH UPSTREAM
OBSERVATIONS...THAT A TEMPORARY STRATOCUMULUS DECK WILL MOVE BACK
IN AS FINAL VORTICITY LOBE CARRIES THROUGH FROM 10Z NW TO 15Z SE.
THESE CLOUDS WILL THEN MIX OUT WITH THE MUCH DRIER AIR MASS
ADVECTING IN...ALONG WITH HIGH PRESSURE BUILDING IN FROM WESTERN
GREAT LAKES REGION.
MAINLY CLEAR NIGHT TONIGHT...THOUGH SOME UNCERTAINTY AS TO WHETHER
AT LEAST A FEW CLOUDS WILL TRY TO HANG ON NEAR POCONOS-
CATSKILLS...WHERE WEAK LOW LEVEL CONVERGENCE WILL COINCIDE WITH
SOME MOISTURE AROUND 850MB. EITHER WAY...LOOKING AT A COOL NIGHT
WITH LOWS IN THE MID 40S TO LOW 50S FOR MOST OF THE AREA...THANKS
TO LOW DEWPOINTS AND RADIATIONAL COOLING...AND LIGHT NORTHEAST
FLOW.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
A VERY QUIET PERIOD SHAPING UP FOR THE CONCLUSION OF THE WORK
WEEK AS HIGH PRESSURE BECOMES FIRMLY ESTABLISHED ACROSS THE FCST
AREA. EXPECT TEMPS TO GRADUALLY MAKE A REBOUND BACK INTO THE
MIDDLE TO UPPER 70S AS EARLY AS THU AFTERNOON WITH A GRADUAL
WARMING TREND THEN ANTICIPATED THROUGH THE UPCOMING WEEKEND AS
HIGH PRESSURE SLIDES NORTHEAST OF THE AREA.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
2 PM UPDATE...
VERY QUIET EXTENDED WITH A LARGE SURFACE HIGH ACROSS THE ENTIRE
EAST COAST OF THE UNITED STATES THROUGH THE WEEKEND INTO AT LEAST
MONDAY AND MAYBE TUESDAY OR WEDNESDAY. A SOUTHWEST FLOW OF
MOISTER AIR COULD CAUSE A FEW SHOWERS OR THUNDERSTORMS ON TUESDAY.
AS USUAL THAT FAR OUT DIFFERENCES BETWEEN THE MODELS ON TIMING AND
STRENGTH. BOTH THE GFS AND ECMWF HAVE A LARGE UPPER LEVEL TROF
MOVING INTO THE PLAINS WHILE A STORM IS OFF THE SE US COAST.
LONG TERM TEMPERATURES START OUT WITH NEAR NORMAL TEMPERATURES
AROUND 80 THAT RISE INTO THE MID TO UPPER 80S NEXT WEEK. DEWPOINT
TEMPS SHOULD BE MOSTLY IN THE 50S. EARLY MORNING VALLEY FOG
POSSIBLE EACH DAY.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
06Z UPDATE...
FRONT MOVING INTO KAVP AT 06Z...AFTER HAVING CLEARED THE REMAINDER
OF THE AREA BETWEEN 00Z-06Z. MODELS CONTINUE TO UNDERESTIMATE
DRYNESS OF AIRMASS BEHIND THE FRONT...WITH GUIDANCE AND LAMP
PROBABILITIES SUGGESTING MVFR OR EVEN IFR FOR MOST SITES THROUGH
REMAINDER OF THE NIGHT. INSTEAD...OTHER THAN POSSIBLE BRIEF IFR
CIG/VIS WITH NARROW SHOWER BAND IMMEDIATELY ALONG FRONT FOR
KAVP 06Z-07Z...LOOKING AT MAINLY VFR BEHIND THE FRONT AREAWIDE...AT
LEAST INITIALLY. A FINAL WEAK UPPER DISTURBANCE BEHIND THE
FRONT...AS CAN NOW BE SEEN BY STRATOCUMULUS UPSTREAM OVER
ONTARIO...WILL ALLOW MVFR DECK TO DEVELOP FOR MOST TERMINALS
DURING THE 10Z-14Z WINDOW /SEE TAFS FOR TIMING DETAILS/. BECAUSE
OF DRYNESS OF INCOMING AIR MASS...NOT EXPECTING IFR DESPITE A COUPLE
HILLTOP MODEL SOUNDINGS SUGGESTING IT DURING THAT TIME. AFTER THE
EARLY MORNING MVFR...STRATOCUMULUS LIFTS AND MIXES OUT COURTESY OF
VERY DRY AIR MASS. NORTHERLY WINDS GUSTING 15-20 KTS DURING THE
DAY WITH VFR...THEN DROPPING TO LESS THAN 10 KTS WITH DECOUPLING
THIS EVENING.
OUTLOOK...
LATE WED NIGHT TO SUNDAY...MAINLY VFR. POSSIBLY EARLY MORNING
IFR/MVFR VALLEY FOG AT KELM.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MDP
SHORT TERM...CMG
LONG TERM...TAC
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1252 PM EDT WED JUN 13 2012
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE NORTH AND MOVE ACROSS THE AREA
THIS EVENING. SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
REDEVELOP ACROSS THE EASTERN CAROLINAS THIS AFTERNOON...WITH THE
BEST CHANCE ALONG THE COAST. HIGH PRESSURE WILL BUILD IN LATE
TONIGHT AND THURSDAY...BRINGING A RELATIVELY COOL AND DRY PATTERN
WHICH WILL PERSIST INTO NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 100 PM WEDNESDAY...NORTHERLY SURFACE WINDS ARE WELL-
ESTABLISHED...BUT LOW-LEVEL MOISTURE IS HANGING TOUGH WITH DEWPOINTS
STILL WITHIN A FEW DEGREES OF 70 THROUGHOUT THE AREA. AN AREA OF
ENHANCED CUMULUS MOVING SOUTHWARD ACROSS EAST-CENTRAL NC IS
ASSOCIATED WITH THE ACTUAL SURFACE COLD FRONT. CONVECTION MAY FIRE
ALONG THIS FEATURE STARTING WITHIN THE NEXT 90 MINUTES. WE`VE
TWEAKED HIGH TEMPERATURES UPWARD BASED ON LATEST OBSERVATIONS...
ESPECIALLY NEAR THE COAST. OTHER CHANGES WERE MINOR. PREVIOUS
DISCUSSION FROM 10 AM FOLLOWS...
SURFACE WINDS HAVE SHIFTED NORTHWESTERLY ALL THE WAY DOWN TO THE
BEACHES THIS MORNING AS A SURFACE TROUGH HAS PUSHED OFF THE COAST.
THE ACTUAL SURFACE COLD FRONT IS LAGGING THIS WIND SHIFT AND SHOULD
MAKE IT OFFSHORE EARLY THIS EVENING. WE`RE LOSING THE DEEP TROPICAL
MOISTURE AS MID-LEVEL WINDS HAVE SHIFTED NORTHWESTERLY BEHIND A
DEPARTING UPPER LEVEL TROUGH. PRECIPITABLE WATER VALUES (CURRENTLY
1.75 INCHES) SHOULD FALL THROUGHOUT THE DAY AND INTO TONIGHT AS
DRIER AIR BUILDS IN MAINLY AT AND ABOVE 700 MB.
WITH MANY MORE BREAKS EXPECTED IN LOW AND MID-LEVEL CLOUD COVER
TODAY COMPARED TO THE PAST SEVERAL DAYS HIGH TEMPERATURES SHOULD
MAKE IT INTO THE 80S EVERYWHERE...WITH SOME UPPER 80S EVEN POSSIBLE
NEAR AND WEST OF LUMBERTON...DILLON AND FLORENCE. THIS WILL STEEPEN
LOW-LEVEL LAPSE RATES SIGNIFICANTLY AND SHOULD CREATE SCATTERED
SHOWERS AND STORMS THIS AFTERNOON. LATEST HRRR MODEL RUNS SHOW WE
SHOULD EXCEED CONVECTIVE TRIGGER TEMPERATURE BETWEEN 17-18Z...1-2 PM
EDT. LOWER PRECIP WATER VALUES WILL NOT BE ABLE TO COMPLETELY NEGATE
THE THREAT OF MORE HEAVY RAINFALL AND ISOLATED FLOODING DUE TO SLOW
CELL MOTION EXPECTED TO BE FROM NORTH TO SOUTH AT ONLY 10-12 MPH.
THERE WILL ALSO BE A THREAT OF GUSTY WINDS AS DRIER AIR ALOFT IS
ENTRAINED INTO THE STORM CELLS WITH DCAPE VALUES INCREASING TO 1000
J/KG OR MORE.
CONVECTIVE ACTIVITY SHOULD END FROM NORTH TO SOUTH THIS EVENING AS
THE ACTUAL COLD FRONT PUSHES OFFSHORE AND DRIER MORE STABLE AIR
BUILDS IN.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...MAIN FORECAST CHALLENGE FOR THE SHORT TERM
WILL BE TEMPERATURES AS MOISTURE WILL BE ON THE DECREASE AS AN OMEGA
CONFIGURATION DEVELOPS AT THE MID LEVELS. AT THE SURFACE A
FORMIDABLE NORTHEAST FLOW WILL DEVELOP AS HIGH PRESSURE BUILDS DOWN
FROM THE NORTHEAST AND LOW PRESSURE MEANDERS NEAR BERMUDA. MET
GUIDANCE IS QUITE A BIT WARMER AS OPPOSED TO THE MAV NUMBERS THROUGH
THE PERIOD MORE-SO THURSDAY. THIS APPEARS TO BE A FUNCTION OF
LINGERING LOW LEVEL MOISTURE VIA THE GFS. NUMBERS JOG TOWARD
SLIGHTLY BETTER AGREEMENT FRIDAY. HAVE LEANED TOWARD THE COOLER MAV
NUMBERS OPTING FOR A SLOWER PROGRESSION OF THE LOW LEVEL MOISTURE.
NO POPS THROUGH THE PERIOD.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 3 AM WEDNESDAY...NO SIGNIFICANT CHANGES TO THE MEDIUM RANGE
GUIDANCE THIS MORNING AS THE FORECAST AREA CONTINUES TO BE SITUATED
IN THE EASTERN PART OF A MID LEVEL OMEGA PATTERN FOR MOST OF THE
PERIOD. I DID INCREASE THE POPS INCREMENTALLY SUNDAY AND MONDAY TO
SLIGHT CHANCE TO MATCH HPC AND ADJACENT OFFICES VIA NORTHEAST
RESULTANT SEA BREEZE COMBINED WITH THE 700MB SUBSIDENCE INVERSION
ABATING. THE PATTERN BEGINS TO CHANGE LATE IN THE PERIOD WITH THE
GFS ADVERTISING A REX BLOCK DEVELOPING SO CONFIDENCE IS BELOW
AVERAGE. NO CHANGES TO TEMPERATURE FORECAST.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AS OF 18Z...ENHANCED CUMULUS VISIBLE ON SATELLITE DROPPING SOUTHWARD
FROM EAST-CENTRAL NORTH CAROLINA ALONG AT LEAST TWO FRONTAL-LIKE
BOUNDARIES. EXPECT SCATTERED CONVECTION TO FIRE ALONG THESE
BOUNDARIES...MAINLY BETWEEN 19-23Z. COVERAGE WILL BE ABOUT 50
PERCENT OF THE AREA. AFTER SUNSET MODELS ARE SHOWING QUITE A BIT OF
ATLANTIC STRATOCUMULUS ADVECTING SOUTHWESTWARD AS SFC LOW PRESSURE
DEVELOPS WELL OFFSHORE. THESE CLOUD BASES COULD LOWER TO MVFR
OVERNIGHT. WILL KEEP THINGS VFR AT THIS TIME BUT CONFIDENCE IS NOT
HIGH. THURSDAY...PREDOMINANTLY VFR WITH CONTINUED NORTHEAST FLOW.
EXTENDED OUTLOOK...MAINLY VFR THROUGH THE FORECAST PERIOD.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 100 PM WEDNESDAY...NO SIGNIFICANT CHANGES TO THE MARINE
FORECAST WITH THIS EARLY AFTERNOON NEAR-TERM UPDATE. PREVIOUS
DISCUSSION FROM 10 AM FOLLOWS...
THUNDERSTORM ACTIVITY HAS PUSHED WELL OFFSHORE AND INTO THE GULF
STREAM...WITH LIGHTER SHOWERS NOW ENDING ACROSS THE COASTAL WATERS.
THERE SHOULD BE A LULL IN CONVECTION LASTING THROUGH EARLY AFTERNOON
BEFORE ADDITIONAL SHOWERS AND THUNDERSTORMS DEVELOPING INLAND BEGIN
TO MOVE OFFSHORE...AFFECTING THE COASTAL WATERS THROUGH THIS
EVENING. WINDS HAVE SHIFTED TO THE WEST OR NORTHWEST THIS MORNING AS
A TROUGH HAS PUSHED OFF THE COAST. THE ACTUAL SURFACE COLD FRONT IS
STILL WELL INLAND AND SHOULD WAIT UNTIL THIS EVENING TO PUSH OFF THE
COAST.
SEAS CURRENTLY RANGE FROM 2-3 FT NEAR THE COAST...BUT EARLIER
SHOWER/STORM ACTIVITY HAS BUILT SEAS TO AROUND 5 FT AT THE FRYING
PAN SHOALS BUOY AND AT THE OFFSHORE LEJEUNE BUOY. SEA HEIGHTS SHOULD
DIMINISH THROUGH EARLY EVENING...BUT MAY BEGIN TO BUILD LATER
TONIGHT AS INCREASING NORTHEAST WINDS DEVELOP BEHIND THE ACTUAL COLD
FRONT.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...A NORTHEASTERLY FLOW WILL PREVAIL
THROUGHOUT THE PERIOD AS HIGH PRESSURE BUILDS DOWN FROM THE
NORTHEAST AND LOW PRESSURE SLOWLY DEVELOPS WELL INTO THE ATLANTIC.
STRONGEST WINDS OCCUR LATE FRIDAY WHEN THE 20-25 KNOT RANGE WILL
LIKELY BE CLOSER TO THE HIGH END OF THE RANGE. THE PERSISTENT FETCH
WILL ALLOW SEAS TO BUILD LATE THURSDAY TO ECLIPSE THE SIX FOOT SMALL
CRAFT CRITERIA AND CONTINUE THROUGH THE REMAINDER OF THE PERIOD.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 3 AM WEDNESDAY...ESSENTIALLY NO CHANGES TO THE EXTENDED
COASTAL WATERS FORECAST AS A NORTHEASTERLY FLOW SHOULD PREVAIL. MAY
SEE MORE VEERING SUNDAY AFTERNOON AS THE FLOW IS LIGHTER ALLOWING
MORE OF A NORTHEAST RESULTANT TO DEVELOP. THE CAVEAT WITH THIS TYPE
OF SCENARIO ARE THE EMBEDDED SURGES. I DID WALK BACK SEAS SLIGHTLY
BUT A SMALL CRAFT ADVISORY MAY STILL BE NEEDED BUT IT APPEARS MORE
MARGINAL AT THIS POINT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...DL/TRA
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
957 AM EDT WED JUN 13 2012
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE NORTH AND MOVE ACROSS THE AREA
THIS EVENING. SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
REDEVELOP ACROSS THE EASTERN CAROLINAS THIS AFTERNOON...WITH THE
BEST CHANCE ALONG THE COAST. HIGH PRESSURE WILL BUILD IN LATE
TONIGHT AND THURSDAY...BRINGING A RELATIVELY COOL AND DRY PATTERN
WHICH WILL PERSIST INTO NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM WEDNESDAY...SURFACE WINDS HAVE SHIFTED NORTHWESTERLY
ALL THE WAY DOWN TO THE BEACHES THIS MORNING AS A SURFACE TROUGH HAS
PUSHED OFF THE COAST. THE ACTUAL SURFACE COLD FRONT IS LAGGING THIS
WIND SHIFT AND SHOULD MAKE IT OFFSHORE EARLY THIS EVENING. WE`RE
LOSING THE DEEP TROPICAL MOISTURE AS MID-LEVEL WINDS HAVE SHIFTED
NORTHWESTERLY BEHIND A DEPARTING UPPER LEVEL TROUGH. PRECIPITABLE
WATER VALUES (CURRENTLY 1.75 INCHES) SHOULD FALL THROUGHOUT THE DAY
AND INTO TONIGHT AS DRIER AIR BUILDS IN MAINLY AT AND ABOVE 700 MB.
WITH MANY MORE BREAKS EXPECTED IN LOW AND MID-LEVEL CLOUD COVER
TODAY COMPARED TO THE PAST SEVERAL DAYS HIGH TEMPERATURES SHOULD
MAKE IT INTO THE 80S EVERYWHERE...WITH SOME UPPER 80S EVEN POSSIBLE
NEAR AND WEST OF LUMBERTON...DILLON AND FLORENCE. THIS WILL STEEPEN
LOW-LEVEL LAPSE RATES SIGNIFICANTLY AND SHOULD CREATE SCATTERED
SHOWERS AND STORMS THIS AFTERNOON. LATEST HRRR MODEL RUNS SHOW WE
SHOULD EXCEED CONVECTIVE TRIGGER TEMPERATURE BETWEEN 17-18Z...1-2 PM
EDT. LOWER PRECIP WATER VALUES WILL NOT BE ABLE TO COMPLETELY NEGATE
THE THREAT OF MORE HEAVY RAINFALL AND ISOLATED FLOODING DUE TO SLOW
CELL MOTION EXPECTED TO BE FROM NORTH TO SOUTH AT ONLY 10-12 MPH.
THERE WILL ALSO BE A THREAT OF GUSTY WINDS AS DRIER AIR ALOFT IS
ENTRAINED INTO THE STORM CELLS WITH DCAPE VALUES INCREASING TO 1000
J/KG OR MORE.
CONVECTIVE ACTIVITY SHOULD END FROM NORTH TO SOUTH THIS EVENING AS
THE ACTUAL COLD FRONT PUSHES OFFSHORE AND DRIER MORE STABLE AIR
BUILDS IN.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...MAIN FORECAST CHALLENGE FOR THE SHORT TERM
WILL BE TEMPERATURES AS MOISTURE WILL BE ON THE DECREASE AS AN OMEGA
CONFIGURATION DEVELOPS AT THE MID LEVELS. AT THE SURFACE A
FORMIDABLE NORTHEAST FLOW WILL DEVELOP AS HIGH PRESSURE BUILDS DOWN
FROM THE NORTHEAST AND LOW PRESSURE MEANDERS NEAR BERMUDA. MET
GUIDANCE IS QUITE A BIT WARMER AS OPPOSED TO THE MAV NUMBERS THROUGH
THE PERIOD MORE-SO THURSDAY. THIS APPEARS TO BE A FUNCTION OF
LINGERING LOW LEVEL MOISTURE VIA THE GFS. NUMBERS JOG TOWARD
SLIGHTLY BETTER AGREEMENT FRIDAY. HAVE LEANED TOWARD THE COOLER MAV
NUMBERS OPTING FOR A SLOWER PROGRESSION OF THE LOW LEVEL MOISTURE.
NO POPS THROUGH THE PERIOD.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 3 AM WEDNESDAY...NO SIGNIFICANT CHANGES TO THE MEDIUM RANGE
GUIDANCE THIS MORNING AS THE FORECAST AREA CONTINUES TO BE SITUATED
IN THE EASTERN PART OF A MID LEVEL OMEGA PATTERN FOR MOST OF THE
PERIOD. I DID INCREASE THE POPS INCREMENTALLY SUNDAY AND MONDAY TO
SLIGHT CHANCE TO MATCH HPC AND ADJACENT OFFICES VIA NORTHEAST
RESULTANT SEA BREEZE COMBINED WITH THE 700MB SUBSIDENCE INVERSION
ABATING. THE PATTERN BEGINS TO CHANGE LATE IN THE PERIOD WITH THE
GFS ADVERTISING A REX BLOCK DEVELOPING SO CONFIDENCE IS BELOW
AVERAGE. NO CHANGES TO TEMPERATURE FORECAST.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AS OF 12Z...MOST OF THE SIGNIFICANT CONVECTION IS OFFSHORE...
ASSOCIATED WITH A PRE-FRONTAL TROUGH. LOOK FOR LIGHT SHOWERS TO
AFFECT THE COASTAL TERMINALS FOR THE FIRST HOUR OR SO...ALONG WITH
INTERMITTENT STRATUS. LOW LEVELS BEGIN TO DRY OUT BY 13Z AS THE
WINDS SHIFT MORE TO THE NORTH AS THE COLD FRONT BEGINS TO PUSH
THROUGH. WILL HAVE TO WATCH THE STRATUS...CURRENT THINKING IS WE
WILL SEE A QUICK TRANSITION TO VFR BY MID MORNING...CONFIDENCE
MODERATE. SHOULD SEE PRETTY FULL SUN BY NOON TODAY. THERE COULD BE
ENOUGH HEATING TO KICK OFF SCATTERED LIGHT SHOWERS MAINLY ALONG THE
COAST THIS AFTERNOON. COVERAGE SHOULD BE LIMITED. TONIGHT...VFR
CONDITIONS WITH LIGHT NORTHEASTERLY WINDS.
EXTENDED OUTLOOK...MAINLY VFR THROUGH THE FORECAST PERIOD.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM WEDNESDAY...THUNDERSTORM ACTIVITY HAS PUSHED WELL
OFFSHORE AND INTO THE GULF STREAM...WITH LIGHTER SHOWERS NOW ENDING
ACROSS THE COASTAL WATERS. THERE SHOULD BE A LULL IN CONVECTION
LASTING THROUGH EARLY AFTERNOON BEFORE ADDITIONAL SHOWERS AND
THUNDERSTORMS DEVELOPING INLAND BEGIN TO MOVE OFFSHORE...AFFECTING
THE COASTAL WATERS THROUGH THIS EVENING. WINDS HAVE SHIFTED TO THE
WEST OR NORTHWEST THIS MORNING AS A TROUGH HAS PUSHED OFF THE COAST.
THE ACTUAL SURFACE COLD FRONT IS STILL WELL INLAND AND SHOULD WAIT
UNTIL THIS EVENING TO PUSH OFF THE COAST.
SEAS CURRENTLY RANGE FROM 2-3 FT NEAR THE COAST...BUT EARLIER
SHOWER/STORM ACTIVITY HAS BUILT SEAS TO AROUND 5 FT AT THE FRYING
PAN SHOALS BUOY AND AT THE OFFSHORE LEJEUNE BUOY. SEA HEIGHTS SHOULD
DIMINISH THROUGH EARLY EVENING...BUT MAY BEGIN TO BUILD LATER
TONIGHT AS INCREASING NORTHEAST WINDS DEVELOP BEHIND THE ACTUAL COLD
FRONT.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...A NORTHEASTERLY FLOW WILL PREVAIL
THROUGHOUT THE PERIOD AS HIGH PRESSURE BUILDS DOWN FROM THE
NORTHEAST AND LOW PRESSURE SLOWLY DEVELOPS WELL INTO THE ATLANTIC.
STRONGEST WINDS OCCUR LATE FRIDAY WHEN THE 20-25 KNOT RANGE WILL
LIKELY BE CLOSER TO THE HIGH END OF THE RANGE. THE PERSISTENT FETCH
WILL ALLOW SEAS TO BUILD LATE THURSDAY TO ECLIPSE THE SIX FOOT SMALL
CRAFT CRITERIA AND CONTINUE THROUGH THE REMAINDER OF THE PERIOD.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 3 AM WEDNESDAY...ESSENTIALLY NO CHANGES TO THE EXTENDED
COASTAL WATERS FORECAST AS A NORTHEASTERLY FLOW SHOULD PREVAIL. MAY
SEE MORE VEERING SUNDAY AFTERNOON AS THE FLOW IS LIGHTER ALLOWING
MORE OF A NORTHEAST RESULTANT TO DEVELOP. THE CAVEAT WITH THIS TYPE
OF SCENARIO ARE THE EMBEDDED SURGES. I DID WALK BACK SEAS SLIGHTLY
BUT A SMALL CRAFT ADVISORY MAY STILL BE NEEDED BUT IT APPEARS MORE
MARGINAL AT THIS POINT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...DL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
254 AM EDT WED JUN 13 2012
.SYNOPSIS...
A COLD FRONT WILL MOVE SLOWLY ACROSS THE AREA TODAY BRINGING WITH
IT MORE RAIN. HIGH PRESSURE WILL BUILD IN THURSDAY AND MAINTAIN A
RELATIVELY COOL AND DRY PATTERN THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1005 PM TUESDAY...DECENT CLUSTER OF SHOWERS AND THUNDERSTORMS
EXTENDS ACROSS THE SE NC COASTAL COUNTIES AND THE ADJACENT COASTAL
AND OFFSHORE WATERS. MOVEMENT IS TO THE ENE NEAR 15 MPH. VIA LATEST
KLTX RAINFALL ESTIMATES...LOOK FOR AN ADDITIONAL ONE TENTH TO ONE
QUARTER OF AN INCH...EXCEPT ONE HALF TO 1 INCH FROM ANY OF THE
STRONGER SHOWERS AND STORMS. THIS CLUSTER/AREA SHOULD TRACK NE OF
THE AREA BY MIDNIGHT TO 1 AM.
THE DEEP PLUME OF MOISTURE FROM THE TROPICS IS SLOWLY BEING CUT OFF
AS THE MID-UPPER LEVEL TROF REACHES THE EASTERN CAROLINAS...VIA THE
LATEST NEAR TERM RUC MODEL HOURLY RUNS. AS A RESULT...THE BEST
CHANCES FOR PCPN AND THE ORIENTATION OF OVERNIGHT POPS ACROSS THE
ILM CWA...WILL CONTINUE TO BE GEARED ALONG THE COASTAL COUNTIES AND
ADJACENT COASTAL/OFFSHORE WATERS. THE 5H VORT ACROSS SOUTHERN GA IS
PROGGED TO TRACK OFF THE GA COAST LATE THIS EVENING AND OVERNIGHT
AND SHOULD NOT BE A PROBLEM FOR THE ILM CWA. WILL HAVE TO MAINLY
DEAL WITH THE APPROACH OF FRONTAL DYNAMICS AND ANY SHEARED MID LEVEL
VORTS ACCOMPANYING IT FOR THE CONTINUED POPS OVERNIGHT. TWEAKED MIN
TEMPS UPWARDS BY A DEGREE OR 2 BASED ON LATEST TRENDS AND A PEAK
LOOK AT THE NEW 00Z GUIDANCE.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3:00 AM WEDNESDAY...MAIN FORECAST CHALLENGE FOR THE SHORT TERM WILL
BE TEMPERATURES AS MOISTURE WILL BE ON THE DECREASE AS AN OMEGA
CONFIGURATION DEVELOPS AT THE MID LEVELS. AT THE SURFACE A
FORMIDABLE NORTHEAST FLOW WILL DEVELOP AS HIGH PRESSURE BUILDS
DOWN FROM THE NORTHEAST AND LOW PRESSURE MEANDERS NEAR BERMUDA.
MET GUIDANCE IS QUITE A BIT WARMER AS OPPOSED TO THE MAV NUMBERS
THROUGH THE PERIOD MORE-SO THURSDAY. THIS APPEARS TO BE A FUNCTION
OF LINGERING LOW LEVEL MOISTURE VIA THE GFS. NUMBERS JOG TOWARD
SLIGHTLY BETTER AGREEMENT FRIDAY. HAVE LEANED TOWARD THE COOLER
MAV NUMBERS OPTING FOR A SLOWER PROGRESSION OF THE LOW LEVEL
MOISTURE. NO POPS THROUGH THE PERIOD.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 3:00 AM WEDNESDAY...NO SIGNIFICANT CHANGES TO THE MEDIUM RANGE
GUIDANCE THIS MORNING AS THE FORECAST AREA CONTINUES TO BE
SITUATED IN THE EASTERN PART OF A MID LEVEL OMEGA PATTERN FOR MOST
OF THE PERIOD. I DID INCREASE THE POPS INCREMENTALLY SUNDAY AND
MONDAY TO SLIGHT CHANCE TO MATCH HPC AND ADJACENT OFFICES VIA
NORTHEAST RESULTANT SEA BREEZE COMBINED WITH THE 700MB SUBSIDENCE
INVERSION ABATING. THE PATTERN BEGINS TO CHANGE LATE IN THE PERIOD
WITH THE GFS ADVERTISING A REX BLOCK DEVELOPING SO CONFIDENCE IS
BELOW AVERAGE. NO CHANGES TO TEMPERATURE FORECAST.
&&
.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
AS OF 06Z...A VARIETY OF CLOUD DECKS EXPECTED OVERNIGHT FROM
UPSTREAM CONVECTIVE DEBRIS TO AREAS OF STRATUS AND STRATO-CUMULUS.
AS A RESULT...CIGS AND VSBYS WILL VARY FROM IFR TO VFR THROUGH
AROUND SUNRISE. IFR/MVFR CIGS AND VSBYS WILL IMPROVE ALL AREAS
OUTSIDE OF CONVECTION THEREAFTER. WILL ALSO INCLUDE TEMPO SHOWERS AT
KLBT 08-10Z AS UPSTREAM CONVECTION CONTINUES TO WEAKEN AS IT MOVES
TO THE SOUTH. CONVECTION IS EXPECTED TO BECOME SCATTERED ONCE
DAYTIME HEATING PEAKS IN THE AFTERNOON. WINDS WILL BE LIGHT AND
VARIABLE NEAR THE FRONTAL BOUNDARY...BUT FOR THE MYRTLES...THE SEA
BREEZE WILL LIKELY DOMINATE IN THE AFTERNOON ALLOWING WINDS TO TURN
ONSHORE.
EXTENDED OUTLOOK...VFR THROUGH THE FORECAST PERIOD.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1005 PM TUESDAY...SCEC WILL BE ALLOWED TO EXPIRE AT MIDNIGHT
FOR THE ILM NC WATERS. UNTIL THE COLD FRONT REACHES THE COASTAL
WATERS WHICH WILL LIKELY BE CLOSER TO DAYBREAK WED...THE SFC PG AND
PATTERN AHEAD OF IT WILL YIELD SW WINDS AROUND 15 KT...OCCASIONALLY
UP TO 20 KT FOR THE LOCAL WATERS OFF CAPE FEAR. AS THE FRONT MOVES
CLOSER WINDS WILL VEER TO THE WSW TOWARD DAYBREAK AND DROP TO 10 TO
15 KT. SIGNIFICANT SEAS WILL RUN 3 TO 4 FT...UP TO 5 FT ACROSS
THE LOCAL WATERS OFF CAPE FEAR THROUGH MIDNIGHT. DOMINANT PERIODS
WILL BE AROUND 6 SECONDS. WIND DRIVEN WAVES WILL DOMINATE SIG SEAS
WITH A CONTINUED UNDERLYING 1 TO 1.5 FT ESE 9-10 SECOND PERIOD
GROUND SWELL.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3:00 AM WEDNESDAY...A NORTHEASTERLY FLOW WILL PREVAIL THROUGHOUT
THE PERIOD AS HIGH PRESSURE BUILDS DOWN FROM THE NORTHEAST AND LOW
PRESSURE SLOWLY DEVELOPS WELL INTO THE ATLANTIC. STRONGEST WINDS
OCCUR LATE FRIDAY WHEN THE 20-25 KNOT RANGE WILL LIKELY BE CLOSER TO
THE HIGH END OF THE RANGE. THE PERSISTENT FETCH WILL ALLOW SEAS TO
BUILD LATE THURSDAY TO ECLIPSE THE SIX FOOT SMALL CRAFT CRITERIA AND
CONTINUE THROUGH THE REMAINDER OF THE PERIOD.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 3:00 AM WEDNESDAY...ESSENTIALLY NO CHANGES TO THE EXTENDED COASTAL
WATERS FORECAST AS A NORTHEASTERLY FLOW SHOULD PREVAIL. MAY SEE MORE
VEERING SUNDAY AFTERNOON AS THE FLOW IS LIGHTER ALLOWING MORE OF A
NORTHEAST RESULTANT TO DEVELOP. THE CAVEAT WITH THIS TYPE OF
SCENARIO ARE THE EMBEDDED SURGES. I DID WALK BACK SEAS SLIGHTLY BUT
A SMALL CRAFT ADVISORY MAY STILL BE NEEDED BUT IT APPEARS MORE
MARGINAL AT THIS POINT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...SHK
NEAR TERM...MBB
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...RJD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
144 AM EDT WED JUN 13 2012
.SYNOPSIS...
A COLD FRONT WILL MOVE SOUTHEAST AND ACROSS THE EASTERN CAROLINAS
WEDNESDAY...MOVING OFFSHORE WEDNESDAY NIGHT. SHOWERS AND
THUNDERSTORMS WILL END AS THE FRONT MOVES OFFSHORE. LOW PRESSURE
SHOULD DEVELOP ALONG THE FRONT THURSDAY...BRINGING NORTHEAST WINDS
AND MILD TEMPERATURES TO THE CAROLINAS THURSDAY INTO SATURDAY. HIGH
PRESSURE WILL BUILD INTO THE AREA FROM THE NORTHEAST EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1005 PM TUESDAY...DECENT CLUSTER OF SHOWERS AND THUNDERSTORMS
EXTENDS ACROSS THE SE NC COASTAL COUNTIES AND THE ADJACENT COASTAL
AND OFFSHORE WATERS. MOVEMENT IS TO THE ENE NEAR 15 MPH. VIA LATEST
KLTX RAINFALL ESTIMATES...LOOK FOR AN ADDITIONAL ONE TENTH TO ONE
QUARTER OF AN INCH...EXCEPT ONE HALF TO 1 INCH FROM ANY OF THE
STRONGER SHOWERS AND STORMS. THIS CLUSTER/AREA SHOULD TRACK NE OF
THE AREA BY MIDNIGHT TO 1 AM.
THE DEEP PLUME OF MOISTURE FROM THE TROPICS IS SLOWLY BEING CUT OFF
AS THE MID-UPPER LEVEL TROF REACHES THE EASTERN CAROLINAS...VIA THE
LATEST NEAR TERM RUC MODEL HOURLY RUNS. AS A RESULT...THE BEST
CHANCES FOR PCPN AND THE ORIENTATION OF OVERNIGHT POPS ACROSS THE
ILM CWA...WILL CONTINUE TO BE GEARED ALONG THE COASTAL COUNTIES AND
ADJACENT COASTAL/OFFSHORE WATERS. THE 5H VORT ACROSS SOUTHERN GA IS
PROGGED TO TRACK OFF THE GA COAST LATE THIS EVENING AND OVERNIGHT
AND SHOULD NOT BE A PROBLEM FOR THE ILM CWA. WILL HAVE TO MAINLY
DEAL WITH THE APPROACH OF FRONTAL DYNAMICS AND ANY SHEARED MID LEVEL
VORTS ACCOMPANYING IT FOR THE CONTINUED POPS OVERNIGHT. TWEAKED MIN
TEMPS UPWARDS BY A DEGREE OR 2 BASED ON LATEST TRENDS AND A PEAK
LOOK AT THE NEW 00Z GUIDANCE.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 PM TUESDAY...THE BAND OF DEEP TROPICAL MOISTURE WILL
BEGIN TO NUDGE OFFSHORE WEDNESDAY AS THE 500 MB UPPER TROUGH
BEGINS TO KICK EAST AND FINALLY OFF THE COAST WEDNESDAY NIGHT.
THE SURFACE COLD FRONT WILL ACCOMPANY THE UPPER TROUGH TO THE COAST
WEDNESDAY AFTERNOON...BUT A WEAK SEABREEZE WILL HOLD UP THE
FRONT`S EASTWARD PROGRESS UNTIL EVENING. THE HIGHEST CHANCES FOR
SHOWERS AND STORMS WEDNESDAY WILL OCCUR NEAR THE COAST WHERE
ENHANCED LOW-LEVEL CONVERGENCE WILL COEXIST WITH THE LINGERING
TROPICAL HIGH-PRECIPITABLE WATER ATMOSPHERE. CONVECTIVE COVERAGE
SHOULD RANGE FROM 50-60 PERCENT ALONG THE COAST TO ONLY 20-30 PERCENT
ALONG AND WEST OF INTERSTATE 95. UNLIKE TODAY...WEDNESDAY`S STORM
MOTION SHOULD BE FROM NORTH TO SOUTH AS THE MID-LEVEL FLOW SHIFTS
BEFORE THE SURFACE FRONT ARRIVES.
DRIER AIR SHOULD OVERSPREAD THE REGION FROM NW TO SE WEDNESDAY
NIGHT WITH MODEL PRECIP WATER VALUES DROPPING FROM ~2.0 INCHES TO
BARELY 0.6 INCHES BY 12Z THURSDAY. MULTIPLE AREAS OF LOW PRESSURE
WILL DEVELOP ALONG THE FRONT WELL OFFSHORE THURSDAY AND THURSDAY
NIGHT. THE MAIN IMPACTS TO LAND WILL BE INCREASING NORTH TO
NORTHEAST WINDS AND ENOUGH COLD ADVECTION TO KEEP TEMPERATURES AND
DEWPOINTS SURPRISINGLY MILD FOR MID-JUNE. ENOUGH ATLANTIC MOISTURE
SHOULD GET ADVECTED BACK ONSHORE LATE THURSDAY AFTERNOON INTO
THURSDAY NIGHT TO SPREAD A BATCH OF LOW CLOUDS INLAND ALONG THE
COAST WITH THE LARGEST IMPACTS EXPECTED AROUND WILMINGTON.
MOS TEMPERATURES LOOK PRETTY GOOD THROUGH THE PERIOD WITH LITTLE
SPREAD SEEN BETWEEN NUMBERS FROM THE GFS...NAM...OR THE
EXPERIMENTAL ECMWF MOS.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 3 PM TUESDAY...SYNOPTIC PATTERN WILL BE CHARACTERIZED BY A
MID-LEVEL RIDGE AXIS EXTENDING FROM THE GREAT LAKES SOUTHWESTWARD TO
THE SOUTHERN PLAINS...AND A MID-LEVEL TROUGH AXIS A FEW HUNDRED
MILES OFF THE CAROLINA COAST. AT THE SURFACE...THIS WILL TRANSLATE
INTO WEDGE SCENARIO AS HIGH PRESSURE EXTENDS SOUTHWARD ALONG THE
EASTERN SIDE OF THE APPALACHIANS...WITH NORTHEASTERLY FLOW KEEPING
TEMPERATURES ON THE COOL SIDE OF CLIMATOLOGY. MODELS SUGGEST THIS
PATTERN WILL PERSIST THROUGH THE EXTENDED PERIOD.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AS OF 06Z...A VARIETY OF CLOUD DECKS EXPECTED OVERNIGHT FROM
UPSTREAM CONVECTIVE DEBRIS TO AREAS OF STRATUS AND STRATO-CUMULUS.
AS A RESULT...CIGS AND VSBYS WILL VARY FROM IFR TO VFR THROUGH
AROUND SUNRISE. IFR/MVFR CIGS AND VSBYS WILL IMPROVE ALL AREAS
OUTSIDE OF CONVECTION THEREAFTER. WILL ALSO INCLUDE TEMPO SHOWERS AT
KLBT 08-10Z AS UPSTREAM CONVECTION CONTINUES TO WEAKEN AS IT MOVES
TO THE SOUTH. CONVECTION IS EXPECTED TO BECOME SCATTERED ONCE
DAYTIME HEATING PEAKS IN THE AFTERNOON. WINDS WILL BE LIGHT AND
VARIABLE NEAR THE FRONTAL BOUNDARY...BUT FOR THE MYRTLES...THE SEA
BREEZE WILL LIKELY DOMINATE IN THE AFTERNOON ALLOWING WINDS TO TURN
ONSHORE.
EXTENDED OUTLOOK...VFR THROUGH THE FORECAST PERIOD.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1005 PM TUESDAY...SCEC WILL BE ALLOWED TO EXPIRE AT MIDNIGHT
FOR THE ILM NC WATERS. UNTIL THE COLD FRONT REACHES THE COASTAL
WATERS WHICH WILL LIKELY BE CLOSER TO DAYBREAK WED...THE SFC PG AND
PATTERN AHEAD OF IT WILL YIELD SW WINDS AROUND 15 KT...OCCASIONALLY
UP TO 20 KT FOR THE LOCAL WATERS OFF CAPE FEAR. AS THE FRONT MOVES
CLOSER WINDS WILL VEER TO THE WSW TOWARD DAYBREAK AND DROP TO 10 TO
15 KT. SIGNIFICANT SEAS WILL RUN 3 TO 4 FT...UP TO 5 FT ACROSS
THE LOCAL WATERS OFF CAPE FEAR THROUGH MIDNIGHT. DOMINANT PERIODS
WILL BE AROUND 6 SECONDS. WIND DRIVEN WAVES WILL DOMINATE SIG SEAS
WITH A CONTINUED UNDERLYING 1 TO 1.5 FT ESE 9-10 SECOND PERIOD
GROUND SWELL.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 PM TUESDAY...A SURFACE COLD FRONT WILL MAKE ITS WAY DOWN
TO THE COAST MORNING WEDNESDAY...BUT IT SHOULD STALL NEAR THE
BEACHES DURING THE AFTERNOON AS A WEAK SEABREEZE HOLDS UP THE
FRONT`S PROGRESS EAST. SCATTERED SHOWERS AND STORMS WILL ACCOMPANY
THE SLOW-MOVING FRONT WEDNESDAY. THE FRONT WILL RESUME ITS
OFFSHORE MOVEMENT DURING THE EVENING AND SHOULD MOVE WELL OFFSHORE
WEDNESDAY NIGHT. THE 12Z NAM HAS COME INTO AGREEMENT WITH
YESTERDAY`S GFS (AND TODAY`S GFS AS WELL) SHOWING THE DEVELOPMENT
OF MULTIPLE CENTERS OF LOW PRESSURE OFFSHORE THURSDAY ALONG THE
FRONT. THE EXACT LOCATION OF THESE LOWS ARE NOT AS IMPORTANT AS THE
OVERALL IMPACT ON TIGHTENING OUR LOCAL PRESSURE GRADIENT THURSDAY
AFTERNOON INTO THURSDAY NIGHT WITH A SUBSTANTIAL INCREASE IN WIND
SPEEDS EXPECTED ALONG THE COAST. OUR LATEST FORECAST INCREASES WINDS
INTO THE 20-25 KT RANGE THURSDAY NIGHT WITH THE POTENTIAL FOR GUSTS
APPROACHING 30 KT LATE. THIS WILL BUILD SEAS FROM A GENTLE 2-3 FT
WEDNESDAY...TO AS HIGH AS 6-8 FEET NORTH AND EAST OF CAPE FEAR LATE
THURSDAY NIGHT.
LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 3 PM TUESDAY...PERSISTENT NORTHEAST FLOW IS EXPECTED OVER
THE WATERS AS SURFACE HIGH PRESSURE EXTENDS SOUTHWARD ACROSS THE
INLAND CAROLINAS...AND A TROUGH LINGERS WELL OFFSHORE. A MODERATE
PRESSURE GRADIENT ACROSS THE WATERS WILL LIKELY KEEP WINDS IN A
15-25 KT RANGE...AND A PERSISTENT FETCH SHOULD ALLOW SEAS TO BUILD
AS HIGH AS 5-7 FT IN THE 10-20 NM RANGE. SMALL CRAFT ADVISORY
THRESHOLDS WILL BE APPROACHED...IF NOT EXCEEDED AT TIMES FRIDAY AND
SATURDAY...ESPECIALLY ACROSS THE NORTH CAROLINA COASTAL WATERS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...DCH
SHORT TERM...TRA
LONG TERM...CRM
AVIATION...SRP/RJD
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
310 PM CDT WED JUN 13 2012
.SHORT TERM...
CONVECTION CHANCES THROUGHOUT THE PERIOD...INCLUDING THE
POSSIBILITY OF SEVERE LATE TONIGHT...WILL BE THE PRIMARY FORECAST
HEADACHE FOR THE SHORT TERM.
WV LOOP SHOWS THE SHORTWAVE TROUGH THAT BROUGHT SHOWERS TO CENTRAL
MN DURING THE DAY TODAY HEADING OFF TO THE EAST...WITH THE NEXT
SHORTWAVE OVER MT. VIS SAT LOOP HAS SOME FAIRLY VIGOROUS TOWERING
CU OVER THE WESTERN CWA...WHICH FITS WITH MODEL SOUNDINGS SHOWING
AROUND 800 J/KG AND NOT MUCH CAP. HOWEVER...DEVELOPMENT OF ECHOES
ON RADAR HAS NOT REALLY BEEN HAPPENING...AND SPC MESOANALYSIS HAS
THE BEST CAPE FURTHER NORTH AND WEST. HRRR HAS SOME BLIPS IN OUR
SOUTHWESTERN COUNTIES DURING THE LATE AFTERNOON AND EVENING...BUT
QUICKLY DISAPPEARING AND MOST OF THE ACTIVITY COMING IN LATER
TONIGHT AS THE MAIN SHORTWAVE COMES EAST. WILL KEEP AN EYE ON
SATELLITE/RADAR TRENDS...BUT MAY HAVE TO INCLUDE SOME LOW POPS FOR
OUR SOUTHWESTERN COUNTIES IN CASE SOMETHING CAN GET GOING THIS
EVENING.
ALL MODELS ARE IN FAIRLY GOOD AGREEMENT ON DEVELOPING STORMS OUT
IN THE WESTERN DAKOTAS WHERE THE BEST INSTABILITY CURRENTLY
IS...AND BRINGING SOMETHING EASTWARD INTO THE CWA BY MORNING.
THERE IS A FAIR AMOUNT OF ELEVATED CAPE OVER THE SOUTHWESTERN
COUNTIES BY 12Z...AND DEEP LAYER BULK SHEAR INCREASES INTO THE 60
TO 70 KT RANGE. THINK THAT THE PRECIP COULD COME EASTWARD AS A
POSSIBLY SEVERE MCS AFTER MIDNIGHT TONIGHT. INCREASED POPS TO 70
PERCENT OVER OUR SOUTHEASTERN COUNTIES...AND PUT IN A SEVERE
MENTION. WITH PWATS GETTING UP TO AROUND 1.5 INCHES...HEAVY RAIN
COULD BE A POSSIBILITY.
THE UPPER TROUGH WILL MOVE OFF INTO SOUTHERN MANITOBA
TOMORROW...PUSHING THE SFC TROUGH AXIS EASTWARD THROUGH THE CWA.
THUNDERSTORM ACTIVITY SHOULD PUSH EASTWARD AND BE MOSTLY IN MN BY
TOMORROW AFTERNOON. WILL CONTINUE TO HAVE TO WATCH FOR SEVERE
TOMORROW AFTERNOON AS MODELS CONTINUE TO SHOW A GOOD AMOUNT OF
CAPE ABOVE 1500 J/KG AND BULK SHEAR OVER 50 KTS. JUST INCLUDED
LIKELY POPS MENTION THOUGH AND LEFT SEVERE MENTION OUT FOR NOW.
THURSDAY NIGHT AND FRIDAY SHOULD BE FAIRLY QUIET AS WE SEE
SOUTHWESTERLY FLOW ALOFT BETWEEN SYSTEMS. SFC PATTERN WILL BE
FAIRLY WEAK...WITH ANOTHER TROUGH NOT COMING IN UNTIL THE NEXT
SYSTEM STARTS APPROACHING FRIDAY NIGHT. MODELS SHOW SOME
DIFFERENCES IN TIMING ON THE NEXT SHORTWAVE...WITH THE NAM MOST
PROGRESSIVE ON BRINGING THE TROUGH OUT INTO THE PLAINS. LEANED
TOWARDS THE SLOWER GFS AND ECMWF. CONTINUED TO KEEP POPS IN THE
50-70 PERCENT RANGE FOR LATE FRIDAY NIGHT INTO SATURDAY.
TEMPERATURES WILL CONTINUE TO BE FAIRLY WARM...PARTICULARLY FRIDAY
AS BOTH THE NAM AND GFS HAVE 850MB TEMPS APPROACHING 20 C IN THE
SOUTHERN RED RIVER VALLEY. CONTINUED TO KEEP HIGHS IN THE UPPER
70S TO LOW 80S...WITH SOME SLIGHTLY COOLER TEMPS SATURDAY
AFTERNOON. LOWS WILL BE MAINLY IN THE UPPER 50S AND 60S.
.LONG TERM... /SAT NIGHT THROUGH WED/
UPPER WAVE/LOW OVER SOUTH CNTRL CANADA WILL RESULT
IN A SERIES OF WAVES MOVING ACROSS THE NORTHERN TIER...
RESULTING IN A CHANCE OF TSTMS OR SHOWERS THROUGHOUT
THE MAJORITY OF THE PERIOD. BEST CHANCE TO NOT SEE ACTIVITY
WILL BE SAT NIGHT...AS UPPER WAVE EXITS EASTERN ZONES AND
SUBSIDENCE SETS IN. SUN MORNING SHOULD BE DRY AS WELL...BEFORE
THE POTENTIAL FOR CONVECTION INCREASES AGAIN BY SUN AFTN. TEMPS
WILL GENERALLY BE IN THE 70S AS THE PERIOD WILL BE RATHER CLOUDY.
&&
.AVIATION...
CU FIELD WILL SPREAD SOUTH TO NORTH THROUGHOUT THE AFTERNOON AND
INTO THE EVENING...BUT SHOULD DISSIPATE AFTER SUNSET. MAY SEE SOME
BREAKS IN CLOUDS TONIGHT...BUT MID LEVEL DECK WILL PUSH INTO AREA
OVER NIGHT. EXPECT TO SEE SOME SHOWERS AND THUNDERSTORM ACTIVITY
FROM THE SOUTHERN VALLEY THROUGH THE BJI AREA....AND MORE ISOLATED
ACTIVITY AT GFK...TVF AND DVL.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
JR/SPEICHER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
257 PM CDT WED JUN 13 2012
.SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT...
MAIN FORECAST PROBLEM IS THUNDERSTORM CHANCES TONIGHT.
CURRENTLY...SURFACE LOW PRESSURE IS SITUATED OVER SOUTHEAST
MONTANA WITH SOUTHERLY FLOW ACROSS WESTERN AND CENTRAL NORTH
DAKOTA. SHORTWAVE LIFTING FROM NORTHERN MONTANA IN TO SOUTHERN
SASKATCHEWAN IN PRODUCING A BAND OF SHOWERS THAT IS LIFTING ACROSS
NORTHWEST NORTH DAKOTA. MOISTURE CONTINUES TO INCREASE OVER THE
REGION WITH DEWPOINTS CURRENTLY IN THE MID 50S.
MODELS INDICATE SCATTERED CONVECTION DEVELOPING ALONG THE EASTERN
MONTANA COLD FRONT AS IT PUSHES INTO WESTERN NORTH DAKOTA. THE
ONGOING CONVECTION IN THE NORTHWEST MAY ACTUALLY INHIBIT
DESTABILIZATION...BUT WEST CENTRAL AND SOUTHWEST NORTH DAKOTA WILL
SEE MORE SUN THIS AFTERNOON WHICH SHOULD HELP LOWER CONVECTIVE
INHIBITION. CONVECTION WILL HAVE A SLIGHT TO MODERATELY UNSTABLE
ATMOSPHERE TO WORK WITH INITIALLY WITH DECENT 0-6KM SHEAR. IN
ADDITION...INCREASING LOW LEVEL MOISTURE IS NOT UNDERDONE BY
FORECAST MODELS. AS CONVECTION TRACKS INTO CENTRAL NORTH DAKOTA
SHEAR AND CAPE REMAIN BUT THE CAP STRENGTHENS AS YOU MOVE EAST
FROM BISMARCK TO JAMESTOWN. HIGH RESOLUTION MODELS SEEM TO HIT ON
THIS WITH THIS INITIAL CONVECTION HAVING A HARD TIME HOLDING
TOGETHER AS IT MOVES INTO CENTRAL NORTH DAKOTA.
A STRONG SHORTWAVE MOVING THROUGH WESTERN MONTANA THIS AFTERNOON
WILL BE THE TRIGGER FOR EITHER ADDITIONAL THUNDERSTORM
DEVELOPMENT THIS EVENING OR A STRENGTHENING OF CONVECTION THAT
DEVELOPS THIS AFTERNOON ALONG THE EASTERN MT COLD FRONT. THE
LATEST HRRR INDICATES CONVECTION DEVELOPING OVER THE NORTHERN HIGH
PLAINS AND MOVING INTO THE WESTERN DAKOTAS BY MID EVENING AND
TRACKING ACROSS THE LOCAL AREA LATE THIS EVENING AND OVERNIGHT.
EML ADVECTING INTO THE REGION WILL MAINTAIN STEEP LAPSE RATES OVER
THE FORECAST AREA TONIGHT. THIS CONVECTION MAY INITIALLY FORM AS
DISCRETE SUPERCELLS BUT THEN DEVELOP INTO A LINEAR CONVECTIVE
SYSTEM AS IT TRAVERSES THE AREA TONIGHT. ALTHOUGH A TORNADIC
SUPERCELL CANNOT BE RULED OUT LATE THIS AFTERNOON OR THIS
EVENING...THE MAIN THREAT OVERNIGHT WOULD BE LARGE HAIL AND
DAMAGING WINDS. WITH PWATS INCREASING WELL ABOVE NORMAL...HEAVY
RAIN CAN ALSO BE EXPECTED...ESPECIALLY FROM FROM THE FAR SOUTH
CENTRAL INTO THE JAMES RIVER VALLEY. THIS AREA HAS NOT SEEN
SIGNIFICANT RAINFALL LATELY AND THE PROGRESSIVE NATURE OF THE
SYSTEM...WILL NOT ISSUE ANY HYDRO HEADLINES.
PRECIPITATION MAY BE LINGERING IN THE FAR EAST ON THURSDAY
MORNING. OTHERWISE THE MAJORITY OF THE DAY WILL BE DRY ACROSS THE
SOUTHERN TWO THIRDS OF THE CWA. THE FAR NORTH WILL SEE A CHANCE OF
SHOWERS AS THE UPPER LOW TRACKS ACROSS SOUTHERN CANADA. THE SHORT
LIVED DRY SPELL SHOULD CONTINUE THROUGH THURSDAY NIGHT WITH UPPER
LEVEL RIDGING OVER THE LOCAL AREA AHEAD OF THE NEXT SYSTEM.
.LONG TERM...FRIDAY THROUGH NEXT WEDNESDAY...
POTENT UPPER LEVEL WAVE/MID LEVEL CLOSED LOW WILL LIFT ACROSS THE
ROCKIES AND THROUGH THE NORTHERN PLAINS FRIDAY-SATURDAY BRINGING
LIKELY SHOWERS AND THUNDERSTORMS TO MOST LOCATIONS. UNCERTAIN IF WE
WILL SEE WIDESPREAD SEVERE WEATHER THOUGH WITH DAYTIME HEATING ON
FRIDAY LIMITED ALONG WITH MARGINAL CAPE. SCALED BACK CONSIDERABLY ON
POPS SATURDAY AFTERNOON WITH DRY AIR PUNCHING INTO THE REGION FROM
SOUTHWEST TO CENTRAL. LEFT CHANCES IN EAST FOR LINGERING
SHOWERS/THUNDER...AND CHANCES ACROSS THE NORTH NEAR THE TRACK OF THE
MID LEVEL LOW.
DRY CONDITIONS REGION WIDE SATURDAY NIGHT WITH A WEAK RIDGE PUSHING
ACROSS THE NORTHERN PLAINS. AFTERWARDS (SUN-WED)...OUR WEATHER
PATTERN RETURNS TO VERY ACTIVE AS THE UPPER LEVEL JET BECOMES
ORIENTATED OVER THE NORTHERN CONUS AND STEERS SEVERAL MID LEVEL
DISTURBANCES FROM ACROSS THE ROCKIES INTO THE NORTHERN PLAINS.
SHOULD SEE A GOOD CHANCE FOR PRECIPITATION EACH PERIOD.
TEMPERATURES WILL AVERAGE NEAR NORMAL THROUGH THIS
WEEKEND...TRENDING TO NEAR TO SLIGHTLY BELOW NORMAL MON-WED.
&&
.AVIATION...
AN AREA OF SURFACE LOW PRESSURE ACCOMPANIED BY AN UPPER LEVEL
SHORTWAVE WILL COMBINE WITH INCREASINGLY UNSTABLE CONDITIONS TO
BRING THUNDERSTORMS TO WESTERN INTO CENTRAL NORTH DAKOTA THIS
AFTERNOON AND EVENING. MENTIONED VCTS GROUPS FOR ALL BUT KJMS.
HEAVIER THUNDERSTORMS ARE POSSIBLE LATER THIS EVENING AND OVERNIGHT
BEFORE 10Z MAINLY FOR KDIK...KBIS...AND KJMS. WHILE VFR CONDITIONS
SHOULD PREVAIL FOR THE MAJORITY OF THE PERIOD...MVFR-IFR CONDITIONS
CAN BE EXPECTED WITH ANY THUNDERSTORMS WHICH PASS OVER TERMINALS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...TWH
LONG TERM/AVIATION...NH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
429 AM CDT WED JUN 13 2012
.SHORT TERM...NOW THROUGH THURSDAY AFTERNOON...
THE MAIN PROBLEM OF THE DAY IS CONCERNED WITH THE POTENTIAL FOR
SEVERE WEATHER LATER TODAY. THE DAY 1 STORM PREDICTION CENTER
DISCUSSION REFERENCES THUNDERSTORMS FORMING ALONG A SURFACE COLD
FRONT PUSHING INTO THE WESTERN DAKOTAS THIS AFTERNOON...BUT
DOWNPLAYS DAYTIME SEVERE POTENTIAL DUE TO LIMITED INSTABILITY.
THE 00/06 UTC NAM DEPICTS A LINE OF STRONGER THUNDERSTORMS
FORMING...OR STRENGTHENING OF ONGOING CONVECTION...ALONG A LINE
FROM MOBRIDGE SOUTH DAKOTA TO VALLEY CITY NORTH DAKOTA BETWEEN 06
AND 09 UTC THURSDAY MORNING. GREATER INSTABILITY IN THIS REGION
AND FAVORABLE LOW-LEVEL JET SUPPORT SUGGEST THAT STORMS ARE MORE
LIKELY TO BECOME SEVERE THEN...WHICH AGREES WITH THE STORM
PREDICTION CENTER SLIGHT RISK AREA.
THE 06 UTC HRRR DOES INITIATE AT LEAST MODERATE CONVECTION ON THE
MISSOURI SLOPE AT 19 UTC TODAY...BUT IT HAS DIFFICULTY SUSTAINING
IT...WHICH IS CONSISTENT WITH LESS THAN FAVORABLE INSTABILITY
PARAMETERS.
OTHERWISE...GUSTY POST FRONTAL WESTERLIES MAY APPROACH LOWER WIND
ADVISORY CRITERIA THURSDAY AFTERNOON.
.LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...
A BREAK IN THUNDERSTORM ACTIVITY FOR NORTH DAKOTA THURSDAY NIGHT AS
ONE SHORTWAVE EXITS THE AREA AND THE NEXT DISTURBANCE MOVES ACROSS
THE ROCKIES.
AN ACTIVE WEATHER PATTERN CONTINUES THROUGH THE REST OF THE LONG
TERM PERIOD. MODELS IN FAIRLY GOOD AGREEMENT FRIDAY AND SATURDAY
WITH SEVERAL SHORTWAVES MOVING THROUGH THE STATE WITH A PROGRESSIVE
SERIES OF DISTURBANCES. BY SUNDAY THE OVERALL SYNOPTIC WEATHER
PATTERN IS DOMINATED BY A RELATIVELY PERSISTENT BROAD UPPER LEVEL
LOW OVER CENTRAL CANADA...WHICH ALSO BRINGS SEVERAL UPPER LEVEL
SHORTWAVES MOVING ACROSS THE NORTHERN PLAINS...KEEPING A CHANCE OF
PRECIPITATION EACH DAY THROUGH EARLY NEXT WEEK.
THE OVERALL TEMPERATURE TREND IS FOR AVERAGE TEMPERATURES IN THE 70S
TO LOWER 80S FRIDAY...COOLING BY MONDAY TO THE LOW TO MID 70S.
&&
.AVIATION...
SOUTHERLY SURFACE WINDS TODAY AHEAD OF A COLD FRONT THAT IS FORECAST
TO ENTER WESTERN NORTH DAKOTA AFTER 18Z. IFR CIGS IN SOUTH DAKOTA
THIS MORNING ARE EXPECTED TO MOVE INTO THE KBIS/KJMS TAF SITES FOR A
FEW HOURS THIS MORNING...THEN SCATTER OUT FROM WEST TO EAST. WILL
WAIT FOR FINAL DETERMINATION ON THIS CLOSER TO TAF ISSUANCE TIME.
THE SURFACE COLD FRONT WILL BE ACCOMPANIED BY AN UPPER LEVEL
SHORTWAVE...WHICH WILL CREATE INCREASINGLY UNSTABLE CONDITIONS AND
WILL MENTION THUNDERSTORMS WITH VCTS GROUPS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...SCHECK
LONG TERM/AVIATION....JV
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1053 PM EDT THU JUN 14 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 FRIDAY 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 FRIDAY MORNING THROUGH 6 PM FRIDAY/...
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 /FRIDAY 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 /03Z FRIDAY THROUGH TUESDAY/...
RIDGE OF HIGH PRESSURE OVER PA SUPPLYING VFR CONDS AND LIGHT WINDS
LATE THIS EVENING. HOWEVER...POTENTIAL AVIATION CONCERN LATE
TONIGHT...AS 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-11Z.
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 FRIDAY.
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
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1048 PM EDT THU JUN 14 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 FRIDAY 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 FRIDAY MORNING THROUGH 6 PM FRIDAY/...
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 /FRIDAY 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 /03Z FRIDAY THROUGH TUESDAY/...
RIDGE OF HIGH PRESSURE OVER PA WILL CONTINUE TO SUPPLY VFR CONDS
AND LIGHT WINDS THROUGH THIS EVENING. SCT CU WILL TEND TO DIMINISH
AS THE SUN SETS. HOWEVER...POTENTIAL AVIATION CONCERN LATE
TONIGHT...AS MOIST SE FLOW COMBINED WITH RADIATIONAL COOLING COULD
PRODUCE A PERIOD OF LOW CIGS OR FOG ARND DAWN. AT THIS POINT...CONFIDENCE
NOT HIGH ENOUGH TO DROP CONDS TO IFR. HOWEVER...IT/S A DEFINITE
POSSIBILITY BTWN 09Z-11Z.
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 FRIDAY.
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
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
914 PM EDT THU JUN 14 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 BECOMING CENTERED OVER QUEBEC CANADA...
AND LOW PRESSURE DRIFTING SOUTHWARD AWAY FROM THE MID-ATLANTIC
COAST COULD BRING LOW CLOUDS TO SOUTHEASTERN AND CENTRAL PARTS OF
THE STATE THROUGH THE NIGHT AND INTO SATURDAY. TEMPERATURES WILL
REMAIN NEAR NORMAL WITH A GRADUAL MODERATION EXPECTED THROUGH THE
UPCOMING WEEKEND.
&&
.NEAR TERM /UNTIL 7 AM FRIDAY MORNING/...
THE FLAT SCT-BKN CU/STRATOCU FIELD HAS DISSIPATED ACROSS MUCH OF
CENTRAL PENN THIS EVENING. HOWEVER...A PERSISTENT ESE LLVL FETCH
FROM THE WRN ATLANTIC WILL LIKELY KEEP VARIABLE AMOUNTS OF
STRATOCU IN PLACE ACROSS THE SCENT COUNTIES AND PORTIONS OF THE
LOWER SUSQUEHANNA VALLEY OVERNIGHT.
ACROSS THE CENTRAL AND NRN COUNTIES OF THE CWA...THE FORMATION/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. PARTLY CLOUDY SHOULD SUFFICE FOR THE
SKY COVER THROUGH THE OVERNIGHT HOURS.
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 FRIDAY MORNING THROUGH 6 PM FRIDAY/...
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 /FRIDAY 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 /01Z FRIDAY THROUGH TUESDAY/...
RIDGE OF HIGH PRESSURE OVER PA WILL CONTINUE TO SUPPLY VFR CONDS
AND LIGHT WINDS THROUGH THIS EVENING. SCT CU WILL TEND TO DIMINISH
AS THE SUN SETS. HOWEVER...POTENTIAL AVIATION CONCERN LATE
TONIGHT...AS MOIST SE FLOW COMBINED WITH RADIATIONAL COOLING COULD
PRODUCE A PERIOD OF LOW CIGS OR FOG ARND DAWN. AT THIS POINT...CONFIDENCE
NOT HIGH ENOUGH TO DROP CONDS TO IFR. HOWEVER...IT/S A DEFINITE
POSSIBILITY BTWN 09Z-11Z.
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 FRIDAY.
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
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
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.
&&
$$
99/04
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
559 PM CDT WED JUN 13 2012
.DISCUSSION...
SEE 00Z AVIATION DISCUSSION BELOW.
&&
.AVIATION...
VFR CONDITIONS ARE EXPECTED THE NEXT 24 HOURS. WINDS WILL BE SOUTH
AT 10 TO 15 KNOTS WITH A FEW GUSTS TO 20 KNOTS. WATCHING A FEW
TSTMS OVER SOUTHWEST TEXAS. THIS ACTIVITY WILL PROBABLY REMAIN
WELL WEST OF THE TERMINALS.
21
&&
.PREV DISCUSSION... /ISSUED 348 PM CDT WED JUN 13 2012/
SHORT TERM...
WE HAD ISOLATED WEAK CONVECTION EARLY TODAY BUT THIS HAS SINCE
DISSIPATED. SKIES HAVE BECOME MOSTLY CLEAR TO PARTLY CLOUDY ACROSS
THE CWA LIKELY IN RESPONSE TO SUBSIDENCE IN THE WAKE OF THE
DEPARTING MCV ALONG THE RED RIVER VALLEY. A WEAK SURFACE...YET
DISCERNIBLE...BOUNDARY STILL EXISTS OVER THE SOUTHWEST CWA PER THE
KSJT WSR-88D BUT THIS FEATURE REMAINS BENIGN AT THIS TIME. LOOKING
WEST...MID LEVEL RADAR ECHOES HAVE BEEN INCREASING ACROSS
SOUTHWEST TX THIS AFTERNOON AHEAD OF AN APPROACHING SHORTWAVE. AS
THIS SYNOPTIC SCALE ASCENT OVERSPREADS THE AREA AND SURFACE TEMPS
WARM INTO THE MID/UPPER 90S...I ANTICIPATE CONVECTION DEVELOPING
IN THE VICINITY OF THE CWA. CONFIDENCE IS FAIRLY LOW THAT WE WILL
SEE WIDESPREAD THUNDERSTORMS BUT SEVERAL VERSIONS OF THE HIRES WRF
AND THE HRRR ALL AGREE IN THUNDERSTORMS FORMING OVER THE
CENTRAL/EASTERN COUNTIES.
A LOOK AT THE SPC MESO ANALYSIS PAGE DEPICTS SBCAPE VALUES ON THE
ORDER OF 2500-3500 J/KG WITH EFFECTIVE SHEAR VALUES BETWEEN 40-50
KTS. THE QUESTION WILL BE WHETHER OR NOT THE CAP WILL GIVE WAY.
THUS...WE DO HAVE A CONDITIONAL THREAT FOR SEVERE WEATHER BUT I AM
PLAYING THIS RATHER CONSERVATIVE FOR NOW THINKING THAT THE CAP
WILL HOLD FOR THE MOST PART AND ANY CONVECTIVE INITIATION WILL
LIKELY BE DELAYED UNTIL WELL AFTER PEAK HEATING. THUS...I AM ONLY
CARRYING 20 POPS FOR THE PERIOD BEGINNING AT 00Z. OVERNIGHT TEMPS
WILL FALL INTO THE LOWER 70S /BUT WILL LIKELY BE LOWER IF
CONVECTION DOES DEVELOP/.
GENERALLY DRY AND WARM CONDITIONS ARE EXPECTED FOR THURSDAY WITH
SOUTH WINDS INCREASING TO 10-20 MPH ACROSS THE CWA. HIGHS ARE
EXPECTED TO BE IN THE MID/UPPER 90S.
JOHNSON
LONG TERM...
THURSDAY NIGHT INTO FRIDAY...THE UPPER LEVEL LOW THAT IS
CURRENTLY OVER SOUTHERN CALIFORNIA TODAY WILL BE ENVELOPED BY
ANOTHER LOW THAT WILL MOVE SOUTH ALONG THE CALIFORNIA COAST. THERE
WILL BE AN UPPER LEVEL TROUGH OVER THE GULF COAST REGION AS WELL
WHILE WEST CENTRAL TEXAS WILL BE IN BETWEEN UNDERNEATH RIDGING.
FOR THIS REASON...WILL GO WITH TEMPERATURES SLIGHTLY WARMER THAN
GUIDANCE FOR FRIDAY AND SATURDAY. HAVE NOT EXPANDED ANY OF THE
INHERITED POPS FRIDAY AFTERNOON AND EVENING. IT STILL APPEARS THAT
THE LOW WILL BE TOO FAR WEST TO DIRECTLY INFLUENCE US...AND THAT
MOST OF THE CONVECTION WILL GET GOING IN THE HIGHER TERRAIN OF THE
WEST TEXAS AREA...THEN MOVE SLOWLY TO THE NORTHEAST DURING THE
EVENING HOURS...POSSIBLY MAKING THEIR WAY INTO OUR WESTERN TIER OF
COUNTIES BEFORE DISSIPATING.
THE UPPER LEVEL RIDGING EXPANDS THROUGH THE WEEKEND ACROSS TEXAS
AND THE REST OF THE SOUTHWESTERN U.S. THIS WILL PUSH THE MID/UPPER
LEVEL LOW BACK OUT TO THE PACIFIC...AND KEEP OUR TEMPERATURES
WARMER THAN NORMAL WITH LITTLE CHANCE FOR PRECIPITATION. BY
TUESDAY OF NEXT WEEK...A WEAK MID/UPPER LEVEL TROUGH DEVELOPS
ACROSS THE EASTERN HALF OF TEXAS...AND LOOKS TO DRIFT SLOWLY
WEST/SOUTHWEST ACROSS THE SOUTHERN HALF OF THE STATE. THIS COULD
RESULT IN SOME LOWERED TEMPERATURES...AND THE GFS/ECMWF ALSO TRY
TO SHOW SOME SHRA/TSRA DEVELOPING ACROSS OUR SOUTHEASTERN
COUNTIES. WILL HOLD OFF ON INTRODUCING ANY WX AT THIS TIME...BUT
IT WILL BE WORTH WATCHING.
20
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 72 93 72 94 71 / 20 10 10 10 10
SAN ANGELO 73 98 73 98 71 / 20 10 10 10 10
JUNCTION 74 98 73 94 72 / 20 10 10 10 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
352 PM CDT WED JUN 13 2012
.SHORT TERM...
BOUNDARY LAYER APPEARS TO BE FAIRLY STABLE OVER THE ROLLING PLAINS
THANKS TO OUTFLOW FROM THE STORMS THAT ROLLED ACROSS THIS AREA EARLY
THIS MORNING. ACROSS THE SOUTH PLAINS...LATEST VISIBLE SATELLITE
SHOWS THAT CU FIELD IS TRYING TO DEVELOP AND DEEPEN. RAP BUFKIT
SOUNDINGS CONTINUE TO INDICATE A WEAK CAP THAT IS BROKEN IN A COUPLE
OF HOURS AT KLBB WHILE HOLDING THE CAP IN PLACE FURTHER WEST AT
CLOVIS. SPC MESOSCALE ANALYSIS ALSO SHOWS THE CAP HOLDING OVER THE
ROLLING PLAINS WITH AN UNCAPPED ATMOSPHERE OVER THE SOUTH PLAINS AND
MLCAPE VALUES BETWEEN 3500-4000 J/KG. BULK SHEAR VALUES ARE A BIT
LOWER THAN YESTERDAY OVER THE ENTIRE AREA BUT 30-40 KNOTS IS IN
PLACE ACROSS THE SOUTHWESTERN QUARTER OF THE AREA. THESE FACTORS
COULD POTENTIALLY RESULT IN RAPID DEVELOPMENT OF SEVERE STORMS /IF/
THEY ARE ABLE TO DEVELOP. NOT SURE WHAT TO MAKE OF THE POSSIBLE CAP
OVER THE SOUTH PLAINS AND WHAT THIS MAY DO FOR OUR CHANCES OF
CONVECTION AND ALSO MAKES IT DIFFICULT TO NAIL DOWN THE POP FORECAST
FOR TONIGHT.
WILL HOLD POPS IN THE LOW END OF CHANCE AS THE TTU/OUN WRF AND THE
HRRR HAVE ALL BEEN CONSISTENT IN NOT GENERATING ANY STORMS OVER THE
AREA...WITH THE EXCEPTION OF THE HRRR TRYING TO DEVELOP SOME STORMS
LATE TONIGHT BETWEEN 03 AND 06Z. ALSO AM CONCERNED THAT THE
INCOMING AREA OF ENHANCED CLOUD COVER ON VISIBLE SATELLITE MAY
INDICATE SOME KIND OF POCKET OF COOLER AIR ALOFT AND SOME WEAK LIFT
THAT MAY HELP STORMS TO FIRE. THE FLAVORS OF THE WRF HAVE SHOWN
THAT ACTIVITY IN NORTHEAST NEW MEXICO MAY ORGANIZE INTO ANOTHER
COMPLEX THAT COULD MOVE TOWARDS THE NORTHERN ROLLING PLAINS
OVERNIGHT AND ONCE AGAIN HAVE KEPT SLIGHT CHANCE POPS ACROSS THIS
AREA THROUGH TOMORROW MORNING.
FOR THURSDAY...RIDGE AXIS TRIES TO PUSH OVERHEAD WHICH SHOULD HELP
SUPPRESS CONVECTION A BIT BUT OPTED TO HOLD SLIGHT CHANCE POPS
ACROSS THE WESTERN HALF DEPENDING ON HOW CONVECTION DEVELOPS
TONIGHT. MODELS STILL SHOW CONVECTION DEVELOPING ACROSS THE HIGHER
TERRAIN OF NM TOMORROW AFTERNOON SO CANNOT RULE OUT AN ISOLATED
STORM OR TWO PUSHING TOWARDS THE STATE LINE. TEMPERATURES MAY ALSO
BE A FEW DEGREES WARMER WITH THE RIDGE AXIS OVERHEAD BUT LOW-LEVEL
MOISTURE MAY HELP TO LIMIT THE WARMUP SOMEWHAT.
JORDAN
&&
.LONG TERM...
LATEST WATER VAPOR IMAGERY DISPLAYED A PACIFIC UL DISTURBANCE MOVING
ACROSS CALIFORNIA...AND IS PROGGED TO DIG ESE TOWARDS THE DESERT SW
TOMORROW NIGHT. THIS WILL PROMOTE SOUTHWESTERLY FLOW ALOFT...AND
THUS PERMIT THE DRYLINE TO NEAR THE TEXAS/NEW MEXICO BORDER.
FORECAST MODELS HINT AT ADEQUATE CONVERGENCE ALONG THE DRYLINE...SO
MUCH SO THAT IT WILL OVERCOME THE LESS THAN 100 J/KG OF CIN.
FURTHERMORE...A WEAK EMBEDDED IMPULSE MAY BE ENOUGH TO SPARK
CONVECTION ALONG AND EAST OF THE DRYLINE...AS SOUTHEASTERLY SFC
WINDS EAST OF THE DRYLINE INDUCE DEWPOINTS IN THE 50S AND 60S.
CURRENT THINKING IS THAT THE SAID EMBEDDED IMPULSE WILL EJECT NE
ACROSS THE PANHANDLES...HOWEVER WILL MAINTAIN SLIGHT CHANCE POPS
ACROSS PORTIONS OF THE CENTRAL AND WESTERN ZONES...WHERE PROGGED
SFC-BASED CAPE OF 1.0-1.5 KJ/KG EXISTS. IF STORMS DO INDEED
DEVELOP...STRONG TO SEVERE STORMS WILL BE POSSIBLE WITH HAIL AND
BRIEF GUSTY WINDS THE PRIMARY THREATS.
FRIDAY THROUGH SUNDAY...THE PACIFIC UL DISTURBANCE WILL RETROGRADE
WEST ACROSS THE EASTERN PACIFIC...WHILE CONCURRENTLY A PROGRESSIVE
PATTERN ACROSS THE NORTHERN U.S. TIER ENSUES...WHICH WILL LEAD TO
THE DRYLINE LINGERING ACROSS OR JUST WEST OF THE CWA. DESPITE SLIGHT
HEIGHT INCREASES FROM AN UA RIDGE...MOIST LOW LEVELS WILL EXIST AS
UPSLOPE SFC WINDS PERSIST /PWATS IN EXCESS OF 1.00 INCH/...AND MODEL
SOUNDINGS EXHIBITING STEEPENED LAPSE RATES EACH AFTERNOON/EVENING
/SFC-BASED CAPE OF 2.0-2.5 KJ/KG/ SUGGEST THE POTENTIAL FOR STRONG
TO SEVERE STORMS MORESO ACROSS THE WESTERN ZONES NEAREST TO THE
DRYLINE /HAIL AND GUSTY WINDS THE PRIMARY THREATS/. THE GFS
MAINTAINS BEST POPS ACROSS EASTERN NEW MEXICO COINCIDING WITH THE
DISPLACEMENT OF THE DRYLINE THROUGHOUT THE SAID PERIOD...WHILE THE
NAM AND ECMWF SOLUTIONS ARE A BIT MORE ROBUST /DRYLINE A BIT CLOSER
TO THE FA/. AS SUCH...STORMS APPEAR TO BE DEPENDENT ON THE EXACT
LOCATION OF THE DRYLINE AND WILL THEREFORE OPT TO KEEP POPS BELOW 30
PERCENT ATTM.
MONDAY THROUGH WEDNESDAY THE LONG TERM MODELS DIFFER A BIT IN REGARD
TO THE SYNOPTIC PATTERN. THE GFS RETROGRADES THE UA RIDGE TO THE
SOUTHWESTERN CONUS BY MONDAY AS AN EASTERN CONUS UA RIDGE PROMOTES
AN UA LOW TO MOVE ACROSS SOUTHERN TEXAS AND PERHAPS ALLOW INCREASING
CHANCES FOR PRECIP OFF THE CAPROCK TUESDAY-WEDNESDAY. THE ECMWF ON
THE OTHER HAND ALSO DEVELOPS AN UA RIDGE ACROSS THE EASTERN
CONUS...WHILE A TROPICAL SYSTEM TRANSLATES NORTH ACROSS OLD MEXICO
THUS STREAMING LOW TO MID LEVEL MOISTURE ACROSS THE FA...AND A
CHANCE FOR STORMS. FURTHERMORE...THE ECMWF HINTS AT THE BROAD UA
TROUGH ACROSS THE NORTHERN U.S. TIER TO SURGE A RELATIVELY WEAK DRY
COLD FRONT TO ACROSS FAR THE NWRN ZONES TUESDAY BEFORE QUICKLY
RETREATING NORTH. WILL NEED TO ANALYZE FUTURE MODEL RUNS FOR
CONSENSUS...AND WILL THEREFORE OPT TO MAINTAIN SILENT POPS BEYOND
SUNDAY NIGHT ATTM.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 61 93 64 92 62 / 40 20 20 30 30
TULIA 66 91 65 91 65 / 30 20 20 20 20
PLAINVIEW 69 92 67 91 67 / 30 20 20 20 20
LEVELLAND 69 95 67 93 66 / 30 20 20 20 20
LUBBOCK 69 94 69 93 68 / 30 20 20 20 20
DENVER CITY 69 95 68 94 66 / 30 20 20 30 30
BROWNFIELD 70 95 68 93 66 / 30 20 20 20 20
CHILDRESS 68 94 72 93 71 / 30 10 10 10 10
SPUR 70 94 70 93 69 / 30 10 20 20 20
ASPERMONT 73 95 74 95 71 / 20 10 10 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
14/29
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
348 PM CDT WED JUN 13 2012
.SHORT TERM...
WE HAD ISOLATED WEAK CONVECTION EARLY TODAY BUT THIS HAS SINCE
DISSIPATED. SKIES HAVE BECOME MOSTLY CLEAR TO PARTLY CLOUDY ACROSS
THE CWA LIKELY IN RESPONSE TO SUBSIDENCE IN THE WAKE OF THE
DEPARTING MCV ALONG THE RED RIVER VALLEY. A WEAK SURFACE...YET
DISCERNIBLE...BOUNDARY STILL EXISTS OVER THE SOUTHWEST CWA PER THE
KSJT WSR-88D BUT THIS FEATURE REMAINS BENIGN AT THIS TIME. LOOKING
WEST...MID LEVEL RADAR ECHOES HAVE BEEN INCREASING ACROSS
SOUTHWEST TX THIS AFTERNOON AHEAD OF AN APPROACHING SHORTWAVE. AS
THIS SYNOPTIC SCALE ASCENT OVERSPREADS THE AREA AND SURFACE TEMPS
WARM INTO THE MID/UPPER 90S...I ANTICIPATE CONVECTION DEVELOPING
IN THE VICINITY OF THE CWA. CONFIDENCE IS FAIRLY LOW THAT WE WILL
SEE WIDESPREAD THUNDERSTORMS BUT SEVERAL VERSIONS OF THE HIRES WRF
AND THE HRRR ALL AGREE IN THUNDERSTORMS FORMING OVER THE
CENTRAL/EASTERN COUNTIES.
A LOOK AT THE SPC MESO ANALYSIS PAGE DEPICTS SBCAPE VALUES ON THE
ORDER OF 2500-3500 J/KG WITH EFFECTIVE SHEAR VALUES BETWEEN 40-50
KTS. THE QUESTION WILL BE WHETHER OR NOT THE CAP WILL GIVE WAY.
THUS...WE DO HAVE A CONDITIONAL THREAT FOR SEVERE WEATHER BUT I AM
PLAYING THIS RATHER CONSERVATIVE FOR NOW THINKING THAT THE CAP
WILL HOLD FOR THE MOST PART AND ANY CONVECTIVE INITIATION WILL
LIKELY BE DELAYED UNTIL WELL AFTER PEAK HEATING. THUS...I AM ONLY
CARRYING 20 POPS FOR THE PERIOD BEGINNING AT 00Z. OVERNIGHT TEMPS
WILL FALL INTO THE LOWER 70S /BUT WILL LIKELY BE LOWER IF
CONVECTION DOES DEVELOP/.
GENERALLY DRY AND WARM CONDITIONS ARE EXPECTED FOR THURSDAY WITH
SOUTH WINDS INCREASING TO 10-20 MPH ACROSS THE CWA. HIGHS ARE
EXPECTED TO BE IN THE MID/UPPER 90S.
JOHNSON
.LONG TERM...
THURSDAY NIGHT INTO FRIDAY...THE UPPER LEVEL LOW THAT IS
CURRENTLY OVER SOUTHERN CALIFORNIA TODAY WILL BE ENVELOPED BY
ANOTHER LOW THAT WILL MOVE SOUTH ALONG THE CALIFORNIA COAST. THERE
WILL BE AN UPPER LEVEL TROUGH OVER THE GULF COAST REGION AS WELL
WHILE WEST CENTRAL TEXAS WILL BE IN BETWEEN UNDERNEATH RIDGING.
FOR THIS REASON...WILL GO WITH TEMPERATURES SLIGHTLY WARMER THAN
GUIDANCE FOR FRIDAY AND SATURDAY. HAVE NOT EXPANDED ANY OF THE
INHERITED POPS FRIDAY AFTERNOON AND EVENING. IT STILL APPEARS THAT
THE LOW WILL BE TOO FAR WEST TO DIRECTLY INFLUENCE US...AND THAT
MOST OF THE CONVECTION WILL GET GOING IN THE HIGHER TERRAIN OF THE
WEST TEXAS AREA...THEN MOVE SLOWLY TO THE NORTHEAST DURING THE
EVENING HOURS...POSSIBLY MAKING THEIR WAY INTO OUR WESTERN TIER OF
COUNTIES BEFORE DISSIPATING.
THE UPPER LEVEL RIDGING EXPANDS THROUGH THE WEEKEND ACROSS TEXAS
AND THE REST OF THE SOUTHWESTERN U.S. THIS WILL PUSH THE MID/UPPER
LEVEL LOW BACK OUT TO THE PACIFIC...AND KEEP OUR TEMPERATURES
WARMER THAN NORMAL WITH LITTLE CHANCE FOR PRECIPITATION. BY
TUESDAY OF NEXT WEEK...A WEAK MID/UPPER LEVEL TROUGH DEVELOPS
ACROSS THE EASTERN HALF OF TEXAS...AND LOOKS TO DRIFT SLOWLY
WEST/SOUTHWEST ACROSS THE SOUTHERN HALF OF THE STATE. THIS COULD
RESULT IN SOME LOWERED TEMPERATURES...AND THE GFS/ECMWF ALSO TRY
TO SHOW SOME SHRA/TSRA DEVELOPING ACROSS OUR SOUTHEASTERN
COUNTIES. WILL HOLD OFF ON INTRODUCING ANY WX AT THIS TIME...BUT
IT WILL BE WORTH WATCHING.
20
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 72 93 72 94 71 / 20 10 10 10 10
SAN ANGELO 73 98 73 98 71 / 20 10 10 10 10
JUNCTION 74 98 73 94 72 / 20 10 10 10 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
1249 PM CDT WED JUN 13 2012
.UPDATE...
18Z AVIATION DISCUSSION IS BELOW. DIFFICULT FORECAST FOR THIS
AFTERNOON AS NONE OF THE MESOSCALE MODELS ARE INDICATING
CONVECTION OVER THE FORECAST AREA...THE OPERATIONAL RUNS ARE...
AND THE LATEST RAP RUN WEAKENS THE CAP CONSIDERABLY WHICH ALL MEAN
CONDITIONS WILL NEED TO BE WATCHED. DEEP LAYER SHEAR PROFILE IS
MUCH WEAKER THAN YESTERDAY WITH SURFACE WINDS VEERING TO MORE OF A
SOUTHERLY DIRECTION THROUGH THE DAY AS OPPOSED TO SOUTHEASTERLY.
THERE IS A WEAK SURFACE TROF OVER THE AREA WHICH MAY PROVIDE AN
AREA OF SURFACE-BASED CONVERGENCE AND IF THE LATEST RAP RUNS ARE
CORRECT...SBCAPE VALUES OF BETWEEN 2000-3500 J/KG MAY BE REALIZED.
THESE TWO FEATURES MEAN THAT THERE IS STILL A POTENTIAL FOR SEVERE
CONVECTION THIS AFTERNOON...HOWEVER CONFIDENCE IS STILL PRETTY
LOW WHEN/IF ANYTHING CAN GO. WITH CAPE VALUES THIS HIGH...LARGE
HAIL WILL BE THE PRIMARY THREAT ALONG WITH SOME LOCALLY HEAVY
RAINFALL. WILL KEEP POPS THE WAY THEY ARE FOR NOW AND WILL
EVALUATE THROUGH THE DAY TO SEE IF THERE ARE ANY AREAS SHOWING A
TENDENCY FOR CONVECTIVE DEVELOPMENT AND ADJUST IF NEEDED.
JORDAN
&&
.AVIATION...
MVFR CONDITIONS AT KCDS SHOULD GRADUALLY GIVE WAY TO VFR THIS
AFTERNOON WITH VFR IN PLACE IN LUBBOCK. THERE DOES REMAIN A CHANCE
WE COULD SEE STORMS AT BOTH TERMINALS BUT THE TIMING OF THIS
POSSIBILITY IS HIGHLY UNCERTAIN AT THIS TIME AND WILL NOT INCLUDE
IN THE TAFS FOR NOW. MVFR CEILINGS COULD REDEVELOP AT BOTH
TERMINALS OVERNIGHT IF THERE ARE STORMS IN THE AREA AND WILL ALSO
MONITOR FOR POSSIBLE INCLUSION IN LATER TAF ISSUANCES.
JORDAN
&&
.PREV DISCUSSION... /ISSUED 640 AM CDT WED JUN 13 2012/
AVIATION...
OUTFLOW FROM OVERNIGHT CONVECTION WILL BRING MOIST EASTERLY WINDS
ACROSS THE AREA THIS MORNING WITH THE POTENTIAL FOR AREAS OF LOW
STRATUS. SAT IMAGERY AT 630 AM SHOWS EXPANDING STRATUS FIELD
ACROSS THE WESTERN SOUTH PLAINS. WITH LOW CONFIDENCE THAT MVFR
CEILINGS WILL IMPACT EITHER TERMINAL WE HAVE KEPT TAFS VFR FOR
NOW. THIS EVENING...WE EXPECT SCATTERED TSTM ACTIVITY ACROSS ERN
NM AND WRN SPLNS TO MOVE EAST TOWARD BOTH TERMINALS...WITH HIGHER
CONFIDENCE THAT STORMS WILL REACH THE CENTRAL SOUTH PLAINS WE HAVE
ADDED A PROB30 TO KLBB.
PREV DISCUSSION... /ISSUED 410 AM CDT WED JUN 13 2012/
DISCUSSION...
CONVECTIVE INITIATION AND LOCATION TODAY STILL REMAINS HIGHLY
UNCERTAIN ESPECIALLY WITH CONVECTION FROM EARLY THIS MORNING
STABILIZING THINGS OUT. WINDS SHOULD STILL BE ABLE TO SWING BACK
AROUND TO THE SOUTHEAST BY LATER THIS MORNING WITH STRONG SURFACE
DESTABILIZATION BY THE AFTERNOON. WITH THE OUTFLOW...A STRONG CAP
WILL BE IN PLACE AT LEAST THROUGH THE EARLY AFTERNOON. STEEP MID
LEVEL LAPSE RATES WILL CONTRIBUTE TO VERY STRONG SURFACE CAPE
VALUES BETWEEN 3000 AND 4000 J/KG ON THE CAPROCK. HOWEVER...LIFT
WILL BE SIGNIFICANTLY WEAKER THAN OBSERVED EARLY THIS MORNING. MID
AND UPPER LEVEL FLOW WILL BE WEAKER. UPPER LEVEL LIFT WILL
GENERALLY BE LESS ROBUST WITH A VERY WEAK JET MAX MOVING OVERHEAD.
THE ONLY LOW LEVEL CONVERGENCE WILL BE FOUND NEAR THE MOUNTAINS IN
EASTERN NEW MEXICO. WEAK HEIGHT FALLS WILL NOT MOVE INTO THE AREA
UNTIL EARLY THIS EVENING. CONVECTION DOES APPEAR POSSIBLE BUT
LOCATION IS EXTREMELY DIFFICULT TO DETERMINE AT THE MOMENT. THE
BEST CHANCES WILL LIKELY EXIST ON THE CAPROCK THIS EVENING.
BEGINNING ON THURSDAY...A TROUGH WILL AMPLIFY ACROSS THE DESERT
SOUTHWEST. THIS WILL CAUSE THE UPPER FLOW OVER WEST TEXAS TO TURN
SOUTHWESTERLY. HOWEVER...THIS FLOW WILL ALSO SUBSTANTIALLY WEAKEN.
HEIGHT RISES ON THURSDAY WILL ALSO NOT BODE WELL FOR CONVECTION.
LOW LEVEL SOUTHEASTERLY FLOW WILL CONTINUE TO KEEP MOISTURE IN THE
AREA. NONETHELESS...HAVE STILL INCLUDED SLIGHT CHANCES FOR THUNDER
ACROSS WESTERN AREAS ON THURSDAY. PRECIPITATION CHANCES MAY BE
BETTER ON FRIDAY WHEN THE MID AND UPPER FLOW WILL INCREASE A BIT.
DIFFLUENCE WILL ALSO BE SEEN ALOFT ALTHOUGH THE JET MAX WILL STILL
BE WELL TO THE SOUTHWEST OF THE REGION. DETAILS ARE STILL SKETCHY
FOR THE WEEKEND WITH CONVECTION POSSIBLE EACH DAY THROUGH SUNDAY.
SOUTHEASTERLY FLOW WILL HELP TO KEEP LOW LEVEL MOISTURE IN THE
AREA WITH AN UNSTABLE ATMOSPHERE DURING THE AFTERNOON HOURS.
PRECIPITABLE WATER VALUES WILL ALSO INCREASE THROUGH THE WEEKEND
BEGINNING ON FRIDAY. MODELS ALSO SHOW MID LEVEL TEMPERATURES
COOLING ON SATURDAY AND SUNDAY INDICATING INCREASED INSTABILITY
AND LESS CHANCE OF A CAP THESE DAYS. THINGS LOOK TO THEN DRY OUT A
BIT EARLY NEXT WEEK WITH A POSSIBLE FRONTAL PASSAGE ON TUESDAY.
JDV
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 89 64 92 63 91 / 30 30 20 20 30
TULIA 86 64 91 64 91 / 30 30 20 20 20
PLAINVIEW 85 65 91 66 91 / 30 30 20 20 20
LEVELLAND 91 67 94 66 92 / 30 30 20 20 20
LUBBOCK 89 69 93 68 92 / 30 30 20 20 20
DENVER CITY 94 70 94 69 92 / 30 30 20 20 30
BROWNFIELD 93 70 94 69 92 / 30 30 20 20 20
CHILDRESS 88 70 92 72 93 / 30 30 10 10 10
SPUR 90 69 93 69 93 / 30 30 20 20 10
ASPERMONT 93 72 95 73 95 / 20 20 10 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/99/99
AREA FORECAST DISCUSSION
NWS SPOKANE WA
430 PM PDT Thu Jun 14 2012
.SYNOPSIS...
A progressive flow off of the north Pacific will maintain cooler
than normal temperatures over the region for the next week. from
time to time weak disturbances will ride this flow bringing a
chance of mainly mountain showers to the area. Stronger systems
with the potential for more widespread showers will arrive for the
new work week.
&&
.DISCUSSION...
Tonight and Friday...The last in the recent series of relatively
weak upper level short waves is transiting the region today. With
a much more stable air mass and less moisture to work with this
wave is much more benign with mainly thick mid level and high
clouds. Still...the HRRR radar extrapolation based model suggests
the potential for a few showers kicking off this evening over the
northern mountains closest to the trough base dynamic region and
instability area under the cool pool aloft...which will pass
through southern BC tonight. Otherwise...a generally benign
weather regime is expected overnight. The trough will bring a
gradient push through the gaps in the Cascades and promote breezy
evening conditions over the deep basin as surface high pressure
builds into the area.
on Friday a weak short wave ridge will become established over the
region for dryer and warmer conditions...but still not up to
normal temperature-wise. The ridging will effectively suppress
any chance of showers even in the mountains. Friday will be a
pleasant and likely mostly sunny spring day...although more like a
May spring day rather than a mid-June spring day. /Fugazzi
Friday night through Sunday night: The large scale flow across
the Pac NW will transition to a moist zonal flow Friday night
and then toward more of a troffy pattern Sunday night. We can
expect a relatively tranquil weather day on Saturday followed by
increasing precipitation chances Saturday night and Sunday.
Throughout the period, precipitation chances will be highest
across the northern and eastern mountains with mostly dry
conditions expected in the lee of the Cascades and majority of the
western Basin. Models have also trend significantly wetter for the
Palouse and Idaho Panhandle compared to previous runs and these
changes were reflected in the latest forecast.
There is a very impressive and rich moisture fetch crossing into
the Eastern Pacific Basin with AMSU satellite imagery indicating
over an 1.50" of precipitable water near 160W. A strong westerly
jet setting up between the Gulf of Alaska low and high pressure
off the CA coast will transport this moisture into the region
Saturday leading to increasing clouds but very small precipitation
chances away from the Cascade Crest and N mtns where relatively
light rainfall amounts are expected. The first signs of forcing
arrive Saturday night into Sunday per all model guidance as a
shortwave and associated frontal system press through the region.
There are some differences noted with the strength/depth of this
midlevel wave however in one form or another, there is strong
agreement that a cold front will pass through the region Saturday
night into early Sunday morning. Models have trend much wetter
with the warm sector pcpn across NE WA and N ID btwn 00-06z where
upwards of a quarter of an inch is now possible. Further
investigation suggest the presence of strong 305K isentropic
ascent coupled with a layer of 700-500mb negative theta-e lapse
rates so the potential does exist for a burst of heavy shower
activity given these conditions and moisture advecting into the
region.
Late Saturday night/early Sunday...the front slumps into the
region...in a nw to se fashion, models have come into better
agreement of showers...potentially moderate at times, setting
between Ritzville and Mullan. Combined with increasing sw
upsloping flow into the Central Idaho Panhandle Mtns...suggest the
potential for another area of higher QPF amts which as of the 12z
model runs...ranges from 0.25" on the SREF to .35" EC/NAM to .60"
via the GFS over the 6 hr period between 6-12z Sunday. Given the
slower arrival of a midlevel dry slot from previous runs and how
juicy the upstream moisture fetch is, I would not discount the
latest guidance but due to the amount of bouncing around from
previous runs...I only began to show an increase in PoPs and QPF
with expectations that this forecast will need to be further
increased given we achieve stability in the models.
The front will track east of the region early Sunday afternoon
driven by a 130kt NW jet and accompanied midlevel dry slot. This
will result in rapid clearing and drying away from the Cascade
Crest toward the Idaho Panhandle. Low level drying will quickly
cease any additional pcpn threats for points south of line from
Omak to Winchester but the cooler air, on the north side of the
jet, will renew the chance for convective showers and thunderstorms
Sunday afternoon across NE WA and N ID. Shear will definitely be in
the moderate to strong range, but less confidence holds with the
model`s dewpoints and resultant fcst"d" CAPE values so tough to
say exactly what mode of storms if any at all this far in
advance...stay tuned.
We have warmed temperatures for Saturday and cooled slightly for
Sunday yielding temperatures slightly above normal to start the
weekend and near normal to end. /sb
Sunday night through Thursday...Models are in good agreement
through Tuesday that a 120 knot jet stream will be located south
of our area across Oregon. This will place Central and Eastern
Washington and North Idaho on the cold and unstable side of the
jet with a series of waves tracking into the area. This will
result in showers both days especially in the afternoon and
evening hours when the atmosphere is the most unstable. GFS and
ECMWF have the best instability over the mountains of Northeast
Washington and the Idaho Panhandle so a slight chance of
thunderstorms was kept in the forecast. The least shower coverage
will be in the lee of the Cascades due to 850mb winds of 10-20
knots downsloping off the mountains. Overall precipitation chances
were increased Monday and Tuesday based on GFS Ensemble mean pops
and the ECMWF solution. 850mb temperatures drop to around 7-10C
resulting in high temperatures in the valleys mainly in the 60s
to lower 70s which is 5 to 10 degrees below normal. On Wednesday
and Thursday indications are that a ridge will begin to build with
a drying and warming trend. Although some model solutions indicate
a weak wave passing near the Canadian border on Wednesday so some
shower activity may linger over the northern Mountains. The ridge
however does not look to last long with another trough possibly
impacting the Inland Northwest beyond the extended forecast
period. JW
&&
.AVIATION...
00Z TAFS: A weak upper level wave will pass through the region
this evening but the air mass is stable and most of the
associated moisture is high altitude. Thus while occasionally
thick mid level and high cirrus will prevail...ceilings at all TAF
sites will remain AOA 10 Kft MSL. A few evening showers are
possible over the high terrain north of the Columbia Basin and the
high Cascades. Skies will clear overnight and through Friday for VFR
conditions at all TAF sites through 00Z Saturday. /MJF
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 44 72 48 77 54 74 / 10 0 0 0 20 20
Coeur d`Alene 44 70 46 75 52 70 / 20 0 0 0 30 20
Pullman 43 69 45 74 52 72 / 10 0 0 0 30 20
Lewiston 51 77 52 81 58 78 / 10 0 0 0 20 10
Colville 45 78 48 80 51 77 / 20 0 0 10 20 10
Sandpoint 42 71 42 73 51 68 / 20 0 0 10 30 40
Kellogg 43 68 46 71 51 65 / 20 0 0 0 40 40
Moses Lake 49 78 54 86 58 80 / 0 0 0 0 0 0
Wenatchee 50 80 55 82 58 76 / 0 0 0 0 0 0
Omak 44 79 49 81 53 77 / 10 0 0 10 10 0
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
402 PM CDT WED JUN 13 2012
.SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT
356 PM CDT WED JUN 13 2012
AT 3 PM...A CONVECTIVELY INDUCED VORTICITY MAXIMUM WAS MOVING
THROUGH NORTH-CENTRAL IOWA AND SOUTH-CENTRAL MINNESOTA. THE LAPS
INDICATES MODERATE TO STRONG 800-600 MB FRONTOGENESIS ACROSS
SOUTHEAST MINNESOTA AND NORTHEAST IOWA. THE LATEST RAP CONTINUES
TO SHOW THAT THIS FRONTOGENESIS WILL CONTINUE TO WEAKEN LATE THIS
AFTERNOON. AS THIS OCCURS...EXPECT THE BAND OF SHOWERS JUST TO OUR
WEST WILL CONTINUE TO WEAKEN AND DISSIPATE. THIS IS IN GOOD
AGREEMENT WITH THE HRRR...EAST ARW...AND EAST NMM.
FOR TONIGHT...THE 13.12Z MODELS ARE IN GOOD AGREEMENT THAT STRONG
925 TO 700 MB MOISTURE TRANSPORT WILL DEVELOP ACROSS NORTHERN AND
WESTERN MINNESOTA. THIS IS IN RESPONSE TO A WARM FRONT MOVING
THROUGH THIS REGION. ALL OF THE MESO MODELS AND BROADER SCALE
MODELS ARE IN FAIRLY GOOD AGREEMENT THAT A MAJORITY OF THE
PRECIPITATION OVERNIGHT WILL BE WEST OF A CHARLES CITY IOWA TO
DIAMOND LAKE WISCONSIN LINE.
ON THURSDAY AFTERNOON AND EVENING...THE MODELS ARE SHOWING THAT
THERE WILL INCREASING SHEAR ACROSS EASTERN MINNESOTA...AND
NORTHERN WESTERN WISCONSIN AS A STRONG WAVE SHORT WAVE MOVES
ACROSS NORTHERN MINNESOTA. BULK SHEARS CLIMB ABOVE 40 KNOTS ACROSS
THE AFOREMENTIONED AREAS WHICH WILL MAKE IT FAVORABLE FOR THE
DEVELOPMENT OF SUPERCELL THUNDERSTORMS. THE SIGNIFICANT TORNADO
PARAMETER SUGGESTS THAT THERE WILL BE THE POTENTIAL OF TORNADOES.
THE NAM/WRF WOULD SUGGEST EAST-CENTRAL MINNESOTA AND NORTHWEST
WISCONSIN. MEANWHILE THE GFS INDICATES THAT THIS MAY BE A BIT
FURTHER SOUTH AND IT WOULD INCLUDE SOUTHEAST MINNESOTA AND WEST-
CENTRAL WISCONSIN. WHILE THE SHEAR IS GOOD...THERE IS SOME
CONCERN THAT THAT DEW POINTS IN THE MODELS MAY BE A BIT TOO
HIGH...AND IF THIS IS TRUE THAN THE CAPES MAY BE TOO HIGH TOO.
THE TORNADO THREAT WOULD LIKELY IN THE MID TO LATE AFTERNOON...AND
THEN EVOLVE INTO A WIND THREAT AS THE COLD POOLS COALESCE.
BEYOND THIS TIME PERIOD...THERE IS A LOT OF UNCERTAINTY ON WHERE
THE FRONT WILL BE LOCATED ACROSS THE REGION. DUE TO THIS...THERE
IS LOW CONFIDENCE ON BOTH THE TEMPERATURE AND PRECIPITATION
FORECAST.
.LONG TERM...SATURDAY THROUGH WEDNESDAY
356 PM CDT WED JUN 13 2012
ON SATURDAY AND SATURDAY NIGHT...THE MODELS SUGGEST THAT A COLD
FRONT AND UPPER LEVEL TROUGH WILL BE MOVING THROUGH THE REGION.
THE BULK SHEAR WILL ONCE AGAIN CLIMB ABOVE 40 KNOTS. THIS WOULD BE
CONDUCIVE FOR THE DEVELOPMENT OF SUPERCELL THUNDERSTORMS. HOWEVER
THERE IS QUITE A BIT OF UNCERTAINTY ON WHEN THE COLD FRONT WILL
MOVE THROUGH THE REGION AND HOW MUCH INSTABILITY WILL BE AHEAD OF
IT.
ON SUNDAY AND SUNDAY NIGHT...BOTH THE GEM AND ECMWF INDICATE THAT
THE AREA MAY BE DRY AS HIGH PRESSURE BUILDS ACROSS THE REGION.
MEANWHILE THE GFS IS SHOWING YET ANOTHER FRONT MOVING INTO THE
REGION. DUE TO THIS THE ALL BLEND POPS WERE REDUCED SOME.
LOOKING TOWARD THE MIDDLE OF NEXT WEEK...THERE LOOKS TO BE A
PATTERN CHANGE BACK TO NORTHWEST FLOW AS A TROUGH BUILDS ACROSS
THE REGION. THE GFS IS NOT AS AGGRESSIVE AS THE ECMWF. HOWEVER
LOOKING WITH A MADDEN JULIAN OSCILLATION MOVING FROM PHASE 6 TO
7...THE ECMWF WOULD BE THE MOST PROBABLE OUTCOME.
&&
.AVIATION...THROUGH 18Z THURSDAY
101 PM CDT WED JUN 13 2012
VFR CONDITIONS EXPECTED THROUGH THE PERIOD WITH MAIN FORECAST
CONCERNS ON PRECIPITATION CHANCES OVERNIGHT AND THURSDAY. FOR THIS
AFTERNOON...WEAK SHORTWAVE MOVING ACROSS AREA RESULTING IN
ISOLATED SPRINKLES ACROSS SOUTHERN MINNESOTA AND NORTHERN IOWA.
DRY AIR IN THE LOW LEVELS IS KEEPING CLOUD BASES AT OR ABOVE 8
KFT. FOR THE OVERNIGHT...BROKEN TO SCATTERED MID TO HIGH LEVEL
DECK WILL PERSIST AND AS 850 MB MOISTURE TRANSPORT INCREASES TO
THE WEST...SHOWERS AND THUNDERSTORMS LOOK TO DEVELOP ACROSS
CENTRAL MINNESOTA. CURRENT THINKING IS THIS ACTIVITY WILL REMAIN
NORTH AND WEST OF KRST/KLSE SO FOR NOW HAVE LEFT OUT OF TAFS...BUT
WILL NEED TO MONITOR CLOSELY. AN INCREASINGLY TIGHTER PRESSURE
GRADIENT THURSDAY MORNING / AFTERNOON WILL LEAD TO BREEZY
SOUTHERLY WINDS WITH GUSTS TO AROUND 25 KTS AT KRST AND 20 KTS AT
KLSE. LOOKING AHEAD...A COLD FRONT WILL APPROACH THE AREA THURSDAY
EVENING...BRINGING THE CHANCE OF SHOWERS AND THUNDERSTORMS TO THE
AREA.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
356 PM CDT WED JUN 13 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...ZT
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
101 PM CDT WED JUN 13 2012
.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
325 AM CDT WED JUN 13 2012
MAIN FORECAST CONCERN DEALS WITH RAIN CHANCES TODAY THROUGH FRIDAY
NIGHT.
WATER VAPOR IMAGERY AND RAP ANALYSIS AT 2 AM SHOWS A DISTINCT
MID-LEVEL CYCLONIC CIRCULATION MOVING EAST ACROSS CENTRAL SD.
MOISTURE TRANSPORT AND ISENTROPIC LIFT AHEAD OF THE WAVE AIDING IN
SHOWERS AND ISOLATED THUNDERSTORMS ACROSS EASTERN SD/NEB...INTO
NORTHWEST IA. CLOSER TO HOME OVER OUR FORECAST AREA...HIGH CLOUDS
FROM THE DAKOTAS WAVE STREAMING IN WITH CENTER OF HIGH PRESSURE
ACROSS CENTRAL WI INTO CENTRAL LOWER MI. LIGHT WINDS AND PARTLY
CLOUDY CONDITIONS HAS ALLOWED TEMPERATURES TO DIP TO 37 DEGREES AT
BLACK RIVER FALLS WI...WHILE OTHER LOCATIONS RANGED FROM THE 40S TO
THE LOWER 50S UNDER MORE CLOUD COVER.
13.00Z NCEP MODEL SUITE/ECMWF/GEM GENERALLY IN GOOD AGREEMENT
THROUGH THE SHORT TERM PERIOD.
FOR TODAY...WILL BE WATCHING THAT MID-LEVEL WAVE OVER SD MOVES INTO
CENTRAL MN THROUGH THIS AFTERNOON. MODELS CONCENTRATE MAIN AXIS OF
ASSOCIATED 850MB MOISTURE TRANSPORT NORTHWEST INTO MN WITH OUR AREA
JUST ON THE EASTERN FRINGES. MEANWHILE...DECENT AMOUNT OF ISENTROPIC
LIFT INTO THE AREA FOR MID-CLOUD/ACCAS GENERATION. KEPT SMALL
CHANCES OF SHOWERS MAINLY NORTHWEST OF A LINE FROM MEDFORD AND
ARCADIA WI...TO ROCHESTER AND AUSTIN MN. OTHERWISE...WITH INCREASING
CLOUD COVER EXPECTED...HIGHS TODAY ARE EXPECTED TO TOP OFF IN THE
LOWER TO MIDDLE 70S.
TONIGHT...ANOTHER MID-LEVEL WAVE AND SURFACE CYCLOGENESIS WILL TAKE
PLACE OVER NEB/SD WITH MOISTURE TRANSPORT/ISENTROPIC LIFT IMPINGING
ON THE WESTERN PORTIONS OF THE FORECAST AREA. PLANNING ON ISOLATED
SHOWER AND ISOLATED THUNDER //WITH INCREASING ELEVATED MUCAPE//
NORTHWEST OF A MEDFORD-ARCADIA-ROCHESTER-AUSTIN LINE AGAIN IN THE
EVENING...THEN INCREASING SLIGHTLY IN COVERAGE/SPREADING EAST INTO
THE REST OF THE AREA AFTER MIDNIGHT AS 850MB MOISTURE TRANSPORT
VECTORS BEND MORE INTO THE AREA. RAINFALL LOOKS VERY LIGHT WITH
GENERALLY LESS THAN 5 HUNDREDTHS OF AN INCH EXPECTED.
ON THURSDAY...LOOK FOR THE MID-LEVEL WAVE/SURFACE COLD FRONT TO MOVE
INTO MN WITH INCREASING 850MB MOISTURE TRANSPORT INTO THE AREA.
0-3KM MLCAPE INCREASES INTO THE 1000-1500J/KG RANGE ALONG AND AHEAD
OF THE FRONT JUST TO OUR WEST WITH RESPECTABLE 20-30KT 0-3KM BULK
SHEAR. THEREFORE...EXPECTING STRONGER THUNDERSTORM ACTIVITY ALONG
THE FRONT BY AFTERNOON WITH EASTERN FRINGES OF THIS ACTIVITY PERHAPS
MAKING IT INTO NORTHWEST PORTIONS OF THE FORECAST AREA. FOR
NOW...WILL STICK WITH 20-40 PERCENT SHOWER/THUNDERSTORM CHANCE
NORTHWEST OF A SPARTA-VIROQUA-OELWEIN LINE. OTHERWISE...LOOK FOR
HIGH TEMPERATURES IN THE UPPER 70S TO LOWER 80S.
FOR THURSDAY NIGHT THROUGH FRIDAY NIGHT...LOOK FOR THE COLD FRONT
OVER MN TO SINK INTO THE AREA WHILE WEAKENING. MEANWHILE...MODELS
SHOWING A COUPLE MID-LEVELS WAVE EJECTING NORTHEAST TOWARD/ACROSS
THE AREA WITH BOUTS OF LIFT/MOISTURE TRANSPORT. BASED ON THIS
SIGNAL...WILL GO WITH 30-50 SHOWER/THUNDERSTORM CHANCES FOR NOW FOR
THIS PERIOD.
.LONG TERM...SATURDAY THROUGH TUESDAY
325 AM CDT WED JUN 13 2012
13.00Z GFS/ECMWF SHOWING SOUTHWEST FLOW ALOFT INTO THE AREA THROUGH
THE PERIOD AS HIGH PRESSURE ANCHORS IN ACROSS THE EASTERN CONUS AND
A TROUGH SLOWLY MAKES ITS WAY ACROSS THE INTERMOUNTAIN WEST INTO THE
PLAINS. SIGNAL AGREEMENT BETWEEN THE MODELS SEEMS TO BE GETTING
STRONGER FOR PERIODIC SHOWER/THUNDERSTORM CHANCES THROUGH THE
WEEKEND. BOTH MODELS THEN BRING IN A DEEPER TROUGH/STRONGER SURFACE
COLD FRONT INTO THE AREA MONDAY THROUGH TUESDAY FOR CONTINUED
SHOWER/THUNDERSTORM CHANCES.
&&
.AVIATION...THROUGH 18Z THURSDAY
101 PM CDT WED JUN 13 2012
VFR CONDITIONS EXPECTED THROUGH THE PERIOD WITH MAIN FORECAST
CONCERNS ON PRECIPITATION CHANCES OVERNIGHT AND THURSDAY. FOR THIS
AFTERNOON...WEAK SHORTWAVE MOVING ACROSS AREA RESULTING IN
ISOLATED SPRINKLES ACROSS SOUTHERN MINNESOTA AND NORTHERN IOWA.
DRY AIR IN THE LOW LEVELS IS KEEPING CLOUD BASES AT OR ABOVE 8
KFT. FOR THE OVERNIGHT...BROKEN TO SCATTERED MID TO HIGH LEVEL
DECK WILL PERSIST AND AS 850 MB MOISTURE TRANSPORT INCREASES TO
THE WEST...SHOWERS AND THUNDERSTORMS LOOK TO DEVELOP ACROSS
CENTRAL MINNESOTA. CURRENT THINKING IS THIS ACTIVITY WILL REMAIN
NORTH AND WEST OF KRST/KLSE SO FOR NOW HAVE LEFT OUT OF TAFS...BUT
WILL NEED TO MONITOR CLOSELY. AN INCREASINGLY TIGHTER PRESSURE
GRADIENT THURSDAY MORNING / AFTERNOON WILL LEAD TO BREEZY
SOUTHERLY WINDS WITH GUSTS TO AROUND 25 KTS AT KRST AND 20 KTS AT
KLSE. LOOKING AHEAD...A COLD FRONT WILL APPROACH THE AREA THURSDAY
EVENING...BRINGING THE CHANCE OF SHOWERS AND THUNDERSTORMS TO THE
AREA.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
325 AM CDT WED JUN 13 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...ZT
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
634 AM CDT WED JUN 13 2012
.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
325 AM CDT WED JUN 13 2012
MAIN FORECAST CONCERN DEALS WITH RAIN CHANCES TODAY THROUGH FRIDAY
NIGHT.
WATER VAPOR IMAGERY AND RAP ANALYSIS AT 2 AM SHOWS A DISTINCT
MID-LEVEL CYCLONIC CIRCULATION MOVING EAST ACROSS CENTRAL SD.
MOISTURE TRANSPORT AND ISENTROPIC LIFT AHEAD OF THE WAVE AIDING IN
SHOWERS AND ISOLATED THUNDERSTORMS ACROSS EASTERN SD/NEB...INTO
NORTHWEST IA. CLOSER TO HOME OVER OUR FORECAST AREA...HIGH CLOUDS
FROM THE DAKOTAS WAVE STREAMING IN WITH CENTER OF HIGH PRESSURE
ACROSS CENTRAL WI INTO CENTRAL LOWER MI. LIGHT WINDS AND PARTLY
CLOUDY CONDITIONS HAS ALLOWED TEMPERATURES TO DIP TO 37 DEGREES AT
BLACK RIVER FALLS WI...WHILE OTHER LOCATIONS RANGED FROM THE 40S TO
THE LOWER 50S UNDER MORE CLOUD COVER.
13.00Z NCEP MODEL SUITE/ECMWF/GEM GENERALLY IN GOOD AGREEMENT
THROUGH THE SHORT TERM PERIOD.
FOR TODAY...WILL BE WATCHING THAT MID-LEVEL WAVE OVER SD MOVES INTO
CENTRAL MN THROUGH THIS AFTERNOON. MODELS CONCENTRATE MAIN AXIS OF
ASSOCIATED 850MB MOISTURE TRANSPORT NORTHWEST INTO MN WITH OUR AREA
JUST ON THE EASTERN FRINGES. MEANWHILE...DECENT AMOUNT OF ISENTROPIC
LIFT INTO THE AREA FOR MID-CLOUD/ACCAS GENERATION. KEPT SMALL
CHANCES OF SHOWERS MAINLY NORTHWEST OF A LINE FROM MEDFORD AND
ARCADIA WI...TO ROCHESTER AND AUSTIN MN. OTHERWISE...WITH INCREASING
CLOUD COVER EXPECTED...HIGHS TODAY ARE EXPECTED TO TOP OFF IN THE
LOWER TO MIDDLE 70S.
TONIGHT...ANOTHER MID-LEVEL WAVE AND SURFACE CYCLOGENESIS WILL TAKE
PLACE OVER NEB/SD WITH MOISTURE TRANSPORT/ISENTROPIC LIFT IMPINGING
ON THE WESTERN PORTIONS OF THE FORECAST AREA. PLANNING ON ISOLATED
SHOWER AND ISOLATED THUNDER //WITH INCREASING ELEVATED MUCAPE//
NORTHWEST OF A MEDFORD-ARCADIA-ROCHESTER-AUSTIN LINE AGAIN IN THE
EVENING...THEN INCREASING SLIGHTLY IN COVERAGE/SPREADING EAST INTO
THE REST OF THE AREA AFTER MIDNIGHT AS 850MB MOISTURE TRANSPORT
VECTORS BEND MORE INTO THE AREA. RAINFALL LOOKS VERY LIGHT WITH
GENERALLY LESS THAN 5 HUNDRETHS OF AN INCH EXPECTED.
ON THURSDAY...LOOK FOR THE MID-LEVEL WAVE/SURFACE COLD FRONT TO MOVE
INTO MN WITH INCREASING 850MB MOISTURE TRANSPORT INTO THE AREA.
0-3KM MLCAPE INCREASES INTO THE 1000-1500J/KG RANGE ALONG AND AHEAD
OF THE FRONT JUST TO OUR WEST WITH RESPECTABLE 20-30KT 0-3KM BULK
SHEAR. THEREFORE...EXPECTING STRONGER THUNDERSTORM ACTIVITY ALONG
THE FRONT BY AFTERNOON WITH EASTERN FRINGES OF THIS ACTIVITY PERHAPS
MAKING IT INTO NORTHWEST PORTIONS OF THE FORECAST AREA. FOR
NOW...WILL STICK WITH 20-40 PERCENT SHOWER/THUNDERSTORM CHANCE
NORTHWEST OF A SPARTA-VIROQUA-OELWEIN LINE. OTHERWISE...LOOK FOR
HIGH TEMPERATURES IN THE UPPER 70S TO LOWER 80S.
FOR THURSDAY NIGHT THROUGH FRIDAY NIGHT...LOOK FOR THE COLD FRONT
OVER MN TO SINK INTO THE AREA WHILE WEAKENING. MEANWHILE...MODELS
SHOWING A COUPLE MID-LEVELS WAVE EJECTING NORTHEAST TOWARD/ACROSS
THE AREA WITH BOUTS OF LIFT/MOISTURE TRANSPORT. BASED ON THIS
SIGNAL...WILL GO WITH 30-50 SHOWER/THUNDERSTORM CHANCES FOR NOW FOR
THIS PERIOD.
.LONG TERM...SATURDAY THROUGH TUESDAY
325 AM CDT WED JUN 13 2012
13.00Z GFS/ECMWF SHOWING SOUTHWEST FLOW ALOFT INTO THE AREA THROUGH
THE PERIOD AS HIGH PRESSURE ANCHORS IN ACROSS THE EASTERN CONUS AND
A TROUGH SLOWLY MAKES ITS WAY ACROSS THE INTERMOUNTAIN WEST INTO THE
PLAINS. SIGNAL AGREEMENT BETWEEN THE MODELS SEEMS TO BE GETTING
STRONGER FOR PERIODIC SHOWER/THUNDERSTORM CHANCES THROUGH THE
WEEKEND. BOTH MODELS THEN BRING IN A DEEPER TROUGH/STRONGER SURFACE
COLD FRONT INTO THE AREA MONDAY THROUGH TUESDAY FOR CONTINUED
SHOWER/THUNDERSTORM CHANCES.
&&
.AVIATION...TODAY AND TONIGHT
634 AM CDT WED JUN 13 2012
A SOUTH-SOUTHEAST FLOW WILL HELP HOLD DRY AIR IN PLACE IN THE
LOWER LEVELS OF THE ATMOSHPERE...RESULTING IN CONDITIONS REMAINING
VFR THROUGH TONIGHT. THIS FLOW ORIGINATES OUT OF HIGH PRESSURE
MOVING EAST INTO THE GREAT LAKES. ABOVE THIS DRY AIR...MOISTURE
WILL RETURN FROM THE GULF OF MEXICO AHEAD OF A LOW PRESSURE SYSTEM
IN THE DAKOTAS. A FEW SHOWERS AND PERHAPS EVEN THUNDERSTORMS COULD
IMPACT THE KRST TAF SITE AFTER MIDNIGHT...ON THE NOSE OF THIS
MOISTURE RETURN. HOWEVER...CONFIDENCE IS ONLY HIGH ENOUGH TO PUT A
VCSH IN AFTER 06Z. OTHER SHOWERS CURRENTLY PRESENT ON RADAR AROUND
THE SIOUX FALLS AREA ARE EXPECTED TO WEAKEN AND HEAD OFF TO THE
NORTHWEST...STAYING MOSTLY AWAY FROM KRST AND KLSE. REGARDING THE
SOUTH-SOUTHEAST FLOW...THE WINDS SHOULD BECOME GUSTY AT KRST WITH
GUSTS TO 20 KT DUE TO DAYTIME HEATING AND A TIGHTER PRESSURE
GRADIENT THAN AT KLSE. THESE GUSTS WILL END THIS EVENING WITH LOSS
OF HEATING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
325 AM CDT WED JUN 13 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
325 AM CDT WED JUN 13 2012
.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
325 AM CDT WED JUN 13 2012
MAIN FORECAST CONCERN DEALS WITH RAIN CHANCES TODAY THROUGH FRIDAY
NIGHT.
WATER VAPOR IMAGERY AND RAP ANALYSIS AT 2 AM SHOWS A DISTINCT
MID-LEVEL CYCLONIC CIRCULATION MOVING EAST ACROSS CENTRAL SD.
MOISTURE TRANSPORT AND ISENTROPIC LIFT AHEAD OF THE WAVE AIDING IN
SHOWERS AND ISOLATED THUNDERSTORMS ACROSS EASTERN SD/NEB...INTO
NORTHWEST IA. CLOSER TO HOME OVER OUR FORECAST AREA...HIGH CLOUDS
FROM THE DAKOTAS WAVE STREAMING IN WITH CENTER OF HIGH PRESSURE
ACROSS CENTRAL WI INTO CENTRAL LOWER MI. LIGHT WINDS AND PARTLY
CLOUDY CONDITIONS HAS ALLOWED TEMPERATURES TO DIP TO 37 DEGREES AT
BLACK RIVER FALLS WI...WHILE OTHER LOCATIONS RANGED FROM THE 40S TO
THE LOWER 50S UNDER MORE CLOUD COVER.
13.00Z NCEP MODEL SUITE/ECMWF/GEM GENERALLY IN GOOD AGREEMENT
THROUGH THE SHORT TERM PERIOD.
FOR TODAY...WILL BE WATCHING THAT MID-LEVEL WAVE OVER SD MOVES INTO
CENTRAL MN THROUGH THIS AFTERNOON. MODELS CONCENTRATE MAIN AXIS OF
ASSOCIATED 850MB MOISTURE TRANSPORT NORTHWEST INTO MN WITH OUR AREA
JUST ON THE EASTERN FRINGES. MEANWHILE...DECENT AMOUNT OF ISENTROPIC
LIFT INTO THE AREA FOR MID-CLOUD/ACCAS GENERATION. KEPT SMALL
CHANCES OF SHOWERS MAINLY NORTHWEST OF A LINE FROM MEDFORD AND
ARCADIA WI...TO ROCHESTER AND AUSTIN MN. OTHERWISE...WITH INCREASING
CLOUD COVER EXPECTED...HIGHS TODAY ARE EXPECTED TO TOP OFF IN THE
LOWER TO MIDDLE 70S.
TONIGHT...ANOTHER MID-LEVEL WAVE AND SURFACE CYCLOGENESIS WILL TAKE
PLACE OVER NEB/SD WITH MOISTURE TRANSPORT/ISENTROPIC LIFT IMPINGING
ON THE WESTERN PORTIONS OF THE FORECAST AREA. PLANNING ON ISOLATED
SHOWER AND ISOLATED THUNDER //WITH INCREASING ELEVATED MUCAPE//
NORTHWEST OF A MEDFORD-ARCADIA-ROCHESTER-AUSTIN LINE AGAIN IN THE
EVENING...THEN INCREASING SLIGHTLY IN COVERAGE/SPREADING EAST INTO
THE REST OF THE AREA AFTER MIDNIGHT AS 850MB MOISTURE TRANSPORT
VECTORS BEND MORE INTO THE AREA. RAINFALL LOOKS VERY LIGHT WITH
GENERALLY LESS THAN 5 HUNDRETHS OF AN INCH EXPECTED.
ON THURSDAY...LOOK FOR THE MID-LEVEL WAVE/SURFACE COLD FRONT TO MOVE
INTO MN WITH INCREASING 850MB MOISTURE TRANSPORT INTO THE AREA.
0-3KM MLCAPE INCREASES INTO THE 1000-1500J/KG RANGE ALONG AND AHEAD
OF THE FRONT JUST TO OUR WEST WITH RESPECTABLE 20-30KT 0-3KM BULK
SHEAR. THEREFORE...EXPECTING STRONGER THUNDERSTORM ACTIVITY ALONG
THE FRONT BY AFTERNOON WITH EASTERN FRINGES OF THIS ACTIVITY PERHAPS
MAKING IT INTO NORTHWEST PORTIONS OF THE FORECAST AREA. FOR
NOW...WILL STICK WITH 20-40 PERCENT SHOWER/THUNDERSTORM CHANCE
NORTHWEST OF A SPARTA-VIROQUA-OELWEIN LINE. OTHERWISE...LOOK FOR
HIGH TEMPERATURES IN THE UPPER 70S TO LOWER 80S.
FOR THURSDAY NIGHT THROUGH FRIDAY NIGHT...LOOK FOR THE COLD FRONT
OVER MN TO SINK INTO THE AREA WHILE WEAKENING. MEANWHILE...MODELS
SHOWING A COUPLE MID-LEVELS WAVE EJECTING NORTHEAST TOWARD/ACROSS
THE AREA WITH BOUTS OF LIFT/MOISTURE TRANSPORT. BASED ON THIS
SIGNAL...WILL GO WITH 30-50 SHOWER/THUNDERSTORM CHANCES FOR NOW FOR
THIS PERIOD.
.LONG TERM...SATURDAY THROUGH TUESDAY
325 AM CDT WED JUN 13 2012
13.00Z GFS/ECMWF SHOWING SOUTHWEST FLOW ALOFT INTO THE AREA THROUGH
THE PERIOD AS HIGH PRESSURE ANCHORS IN ACROSS THE EASTERN CONUS AND
A TROUGH SLOWLY MAKES ITS WAY ACROSS THE INTERMOUNTAIN WEST INTO THE
PLAINS. SIGNAL AGREEMENT BETWEEN THE MODELS SEEMS TO BE GETTING
STRONGER FOR PERIODIC SHOWER/THUNDERSTORM CHANCES THROUGH THE
WEEKEND. BOTH MODELS THEN BRING IN A DEEPER TROUGH/STRONGER SURFACE
COLD FRONT INTO THE AREA MONDAY THROUGH TUESDAY FOR CONTINUED
SHOWER/THUNDERSTORM CHANCES.
&&
.AVIATION...THROUGH 06Z THURSDAY
1145 PM CDT TUE JUN 12 2012
SURFACE HIGH PRESSURE OVER EASTERN WISCONSIN WILL CONTINUE TO DRIFT
EASTWARD OVERNIGHT AND WEDNESDAY. HIGH CLOUDS WERE ALREADY WORKING
THEIR WAY ACROSS MINNESOTA ON THE BACKSIDE OF THE HIGH AND WILL
CONTINUE TO OVERSPREAD THE TAF SITES TONIGHT. CEILINGS WILL LOWER
INTO THE 8K-12K FOOT RANGE AFTER 12Z. THE EDGE OF THE MOISTURE
TRANSPORT DOES CLIP SOUTHEAST MINNESOTA LATER WEDNESDAY AND THUS
EXPECT SOME SCATTERED SHOWERS. CONFIDENCE NOT HIGH THAT THESE WILL
IMPACT THE TAF SITES. SLIGHTLY BETTER CHANCES AFTER 00Z AS
MOISTURE CONTINUES TO INCREASE. DID ADD MENTION OF VCSH AT KRST
AFTER 00Z AND AT KLSE AFTER 03Z. OTHERWISE...EXPECT SOUTHERLY
WINDS TO GUST TO BETWEEN 20 AND 25 KNOTS AT KRST DURING THE
AFTERNOON HOURS WEDNESDAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
325 AM CDT WED JUN 13 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...RABERDING
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 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 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 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
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
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 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 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
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...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 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...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 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 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 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 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...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
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.
&&
$$