Area Forecast Discussion Issued by NWS Caribou, ME
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000
FXUS61 KCAR 191959
AFDCAR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CARIBOU ME
359 PM EDT WED JUN 19 2013
.SYNOPSIS...
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HIGH PRESSURE ACROSS THE GREAT LAKES WILL SLOWLY BUILD TOWARD THE
REGION TONIGHT AND MOVE EAST OF THE AREA TOMORROW. A COLD FRONT WILL
APPROACH THE REGION LATE THURSDAY NIGHT AND FRIDAY MORNING AND
CROSS THE REGION FRIDAY AFTERNOON. AFTER WEAK HIGH PRESSURE
CROSSES THE REGION FRIDAY NIGHT...ANOTHER LOW PRESSURE SYSTEM
WILL APPROACH ON SATURDAY.-- End Changed Discussion --
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.NEAR TERM /THROUGH THURSDAY/...
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A RIDGE OF HIGH PRESSURE CURRENTLY CENTERED OVER THE EASTERN GREAT
LAKES WILL CONTINUE TO SHIFT EASTWARD TONIGHT, BUILDING RIGHT OVER
NEW ENGLAND. AS SUCH, SKIES WILL QUICKLY CLEAR OUT TONIGHT. THOUGH
WINDS WILL BE LIGHT, WARM AIR ALOFT SPILLING IN ACROSS THE REGION
OVERNIGHT WILL KEEP TEMPS NEAR OR SLIGHTLY ABOVE LAST NIGHT`S/THIS
MORNING`S LOWS. WHILE A FEW OF THE COLDER LOCATIONS IN THE NORTH
MAINE WOODS COULD DROP INTO THE UPPER 30S, MOST PLACES WILL REMAIN
IN THE 40S TONIGHT.
FOR THURSDAY...THE RIDGE AXIS MOVES OFF SHORE, ALLOWING WINDS TO
TURN TO THE SOUTHWEST. MUCH LIKE TODAY, TOMORROW WILL BE DRY WITH
JUST SOME FAIR WEATHER CUMULUS DEVELOPING BY THE AFTERNOON. HIGHS
WILL BE IN THE LOWER TO MID 70S IN MOST SPOTS. THE IMMEDIATE COAST
IS THE EXCEPTION, AS COOL ONSHORE FLOW WILL KEEP TEMPERATURES IN THE
60S.-- End Changed Discussion --
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.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
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THE SHORT TERMS BEGINS FOR OUR FA WITH THE APCH OF A SCT-BKN LN OF
MSLY SHWRS...WITH LITTLE IN THE WAY OF SB AND MU CAPE...FROM ERN
QB INTO NW PTNS OF THE FA THU EVE...WELL AHEAD OF A COLD FRONT
FROM CNTRL CAN. THESE SHWRS WILL CONT TO CROSS MSLY NRN PTNS OF
THE FA LATE THU NGT. WITH CLDS AND SHWRS ADVCG INTO THE N HLF OF
THE FA...OVRNGT LOWS THU NGT SHOULD BE SIG MILDER THAN PREV NGTS.
THE QUESTION THEN TURNS TO HOW MUCH THE ATMOSPHERE COULD RECOVER
OVR THE FA FOR AFTN TSTMS FROM CLDNSS AND SHWRS THAT COULD LAST
WELL INTO THE MORN HRS. LATEST FCST SOUNDINGS FROM THE 12Z OPNL
GFS HAVE BACKED OFF SOMEWHAT FOR FRI AFTN FCST SBCAPES FOR SPCLY
NRN AND CNTRL PTNS OF THE FA...SUGGESTING ONLY 400 TO 700 J/KG
FROM THE PREV RUN OF 700-1100 J/KG FOR THIS PD. WITH THIS IN MIND...
ALG THAT THE SFC COLD FRONT WIND SHIFT WEAKENS AND THE MID LVL
UPPER TROF CROSSES THE FA ARND 18Z...DESTABILIZATION SHOULD BE
MARGINAL IN THE AFTN....ALLOWING FOR SCT SHWRS/TSTMS...WITH NO
NEED FOR ENHANCED TSTM WORDING FOR THIS EVENT ATTM. IN FACT...
MOST IF NOT ALL OF THE ACTIVITY SHOULD MOVE E OF THE FA BY
SUNSET GIVEN THE SPEED OF THE S/WV TROF EXITING THE FA. HI TEMPS
FRI AFTN WILL BE TRICKY...SINCE THERE MAY BE MORE AFTN SUNSHINE
DESPITE WHAT IS IMPLIED WITH SHWR/TSTM CVRG...SINCE DURATION
QPF THIS ACTIVITY WILL BE BRIEF. KEPT CLOSE TO MODEL BLEND HI TEMPS
FOR NOW.
AFT A BRIEF BREAK BETWEEN S/WV TROFS ALF FRI NGT...WHICH THE FA
SHOULD GET CLRG SKIES FRI EVE...ANOTHER FAST MOVG S/WV FROM THE
UPPER GREAT LKS WILL SPREAD CLDNSS INTO SPCLY THE NW HLF OF THE FA
LATE FRI NGT AND POTENTIALLY ANOTHER RND OF SHWRS AND PERHAPS AFTN
TSTMS TO THE FA ON SAT. THERE IS A LOT OF SHORT RANGE MODEL
UNCERTAINTY REGARDING THE TRACK OF THIS S/WV RELATIVE TO UR FA...
WITH 12Z OPNL GFS AND SREF AFFECTING ALL OF OUR FA VS THE 12Z OPNL
ECMWF AFFECTING ONLY SW PTNS OF THE FA. FOR NOW...WE TOOK A BLEND
OF ALL MODELS...AND USING THE IMPLIED FCST OF SBCAPES OF 400 TO
800 J/KG FOR SAT AFTN... INDICATED A CHC OF AFTN TSTMS FOR SRN
PTNS OF THE FA INLAND FROM THE IMMEDIATE COAST. THIS PLACES THE
BEST QPF POTENTIAL OVR THE WRN MTNS...CNTRL AND INTERIOR DOWNEAST
PTNS OF THE FA FROM 12Z SAT-00Z SUN. EVEN SO...WITH LITTLE
CONFIDENCE IN ANY PARTICULAR MODEL SOLUTION...IT WAS HARD TO
JUSTIFY MORE THAN HI CHC POPS AND NO MORE THAN 0.10 INCHES OF 6
HRLY QPF BOTH PDS SAT ATTM. AFT COOLER OVRNGT LOWS LATE FRI NGT/ERLY
SAT MORN...WE WENT A LITTLE BLO ALL MODEL BLEND HI TEMPS SAT AFTN...
SINCE THE PRESENCE OF MUCH CLDNSS AND SHWRS WILL RESULT IN HI
TEMPS SIG COOLER THAN WE ADVERTISE. IF A MORE SRN TRACK OF THE S/WV
ON SAT PANS OUT AS PER THE 12Z ECMWF SOLUTION...WE COULD BE
LOOKING AT AN INVERTED S TO N HI TEMP SCHEME...TO ERLY TO COMMIT
EITHER WAY ATTM.-- End Changed Discussion --
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.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
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FOR THE LONG RANGE PERIOD, THE AREA WILL BE CLOSE TO THE BOUNDARY
DIVIDING VERY WARM AND HUMID AIR TO THE SOUTH AND COOLER AIR WITH
LOWER DEW POINTS TO THE NORTH.
IN TERMS OF THE DAY TO DAY DETAILS, AN INITIAL DISTURBANCE WILL PUSH
SOUTH OF THE AREA SATURDAY NIGHT WITH ANY SHOWERS OR
THUNDERSTORMS COMING TO AN END. SUNDAY LOOKS TO FEATURE FAIR
WEATHER UNDER A MIX OF SUN AND CLOUDS WITH HIGHS IN THE 75 TO 80
DEGREE RANGE EXCEPT COOLER ALONG THE COAST.
MODEL DISCREPANCIES START TO BECOME MORE SIGNIFICANT HEADING INTO
THE BEGINNING OF NEXT WEEK AS THE GFS BRINGS IN THE VERY WARM AND
HUMID AIR WHILE THE GEM AND THE 00Z ECWMF KEEP THE HEAT SOUTH OF
THE AREA WITH CONDITIONS GENERALLY COOLER, CLOUDIER, AND WETTER
ACROSS THE AREA. AT THIS POINT WILL UTILIZE A MODEL BLEND FOR
TEMPERATURES WITH HIGHS GENERALLY FORECAST TO BE IN THE UPPER 70S
TO LOW 80S AND LOWS IN THE UPPER 50S TO MID 60S. EACH DAY WILL
MENTION CHANCES FOR SHOWERS AND STORMS WITH THE BEST CHANCES
OCCURRING MONDAY AND WEDNESDAY.-- End Changed Discussion --
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.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
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NEAR TERM: WITH HIGH PRESSURE OVER THE REGION...VFR CONDITIONS
WITH PARTLY TO MOSTLY CLEAR SKIES ARE EXPECTED THROUGH 00Z FRIDAY.
SHORT TERM: VFR ALL TAF SITES XCPT BRIEFLY MVFR CLGS AND VSBYS
WITH HEAVIER SHWRS AND ANY TSTMS FRI DURG THE DAY AND AGAIN ON
SAT.
MVFR/IFF CONDITIONS WILL BE POSSIBLE INTO SATURDAY NIGHT WITH CONDITIONS
IMPROVING TO VFR SUNDAY. THE APPROACH OF THE NEXT SHORT WAVE WILL
BRING THE POTENTIAL FOR MVFR/IFR CONDITIONS ONCE AGAIN BY MONDAY
DEPENDING ON WHERE THIS WAVE TRACKS.-- End Changed Discussion --
&&
.MARINE...
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NEAR TERM: NO HEADLINES ARE ANTICIPATED THROUGH THURSDAY AS HIGH
PRESSURE WILL BUILD OVER THE WATERS TONIGHT AND TOMORROW.
SHORT TERM: NO HDLNS XPCTD WITH WINDS AND SEAS MSLY BLO 4 FT OVR
OUTER MZS AND 2 FT OR LESS OVR INNER HARBORS...BAYS AND NEAR
COASTLINE AREAS. WW3 GUIDANCE WAS ADJUSTED DOWNWARD FOR OUR WATERS
LATE THU NGT INTO FRI AND AGAIN LATER SAT TO ACCOUNT FOR THE HI SFC
WIND BIAS INTRODUCED INTO THE WW3 MODEL BY THE GFS.
LOW END SCA CONDITIONS WILL BE POSSIBLE AT TIMES LATE MONDAY INTO
TUESDAY AND WEDNESDAY...MAINLY DUE TO HAZARDOUS SEAS.-- End Changed Discussion --
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.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...HASTINGS
SHORT TERM...VJN
LONG TERM...FITZSIMMONS
AVIATION...HASTINGS/VJN
MARINE...HASTINGS/VJN