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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCAR 190433
AFDCAR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CARIBOU ME
1233 AM EDT SUN MAY 19 2013

.SYNOPSIS...
COOL HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH THE WEEKEND.
A WARM FRONT WILL MOVE INTO THE AREA LATE SUNDAY NIGHT INTO MONDAY AS
A SMALL WAVE OF LOW PRESSURE SLIDES IN FROM CANADA.

&&

.NEAR TERM /THROUGH SUNDAY/...
-- Changed Discussion --
1233 AM UPDATE...HIGH PRESSURE IS BUILDING SOUTH OUT OF CANADA
WITH THE RIDGE AXIS PASSING JUST EAST OF MAINE EARLY THIS MORNING.
THE COMBINATION OF A COOL AIR MASS...A MAINLY CLEAR SKY...AND
LIGHT WIND IS ALLOWING TEMPS TO FALL INTO THE 30S ACROSS THE
NORTHERN AND EASTERN ZONES. TEMPS FROM ABOUT MILLINOCKET AND
POINTS SOUTH AND WEST ARE MOSTLY IN THE LOW/MID 40S. THE COLD SPOT
AT MIDNIGHT WAS ESTCOURT STATION IN NORTHERN AROOSTOOK COUNTY AT
28F. TEMPS ALONG COASTAL WASHINGTON COUNTY HAVE DROPPED INTO THE
MID 30S AND WILL EXPAND THE FROST ADVISORY SOUTH INTO COASTAL
WASHINGTON COUNTY WITH THIS UPDATE. OTHER THAN SOME MINOR TWEAKS
TO THE HOURLY TEMP AND SKY GRIDS...NO SIGNIFICANT CHANGES TO THE
FCST ARE PLANNED ATTM.

UPDATE 2215L: JUST A FEW PATCHY CLDS NOTED OTHERWISE MAINLY CLR
SKIES PREVAIL ACROSS THE FA ATTM.  CURRENT FCST APPEARS ON TRACK ATTM...

UPDATE 1915L: ONLY CLDS ACROSS THE AREA CONFINED TO OUR SWRN ZNS
ATTM. ADJUSTED SKY GRIDS TO BETTER FIT CURRENT AND EXPECTED CONDS
THRU THE EVE HRS AND ADJUSTED HRLY TEMPS AS WELL.

CURRENTLY HAVE STRONG RIDGE EXTENDING FROM MARITIMES SOUTHWARD
ACROSS EASTERN MAINE. WEAK TROUGH OVER NORTHWESTERN MAINE
RESULTING IN CLOUDS AND SHOWERS...SOME OF THE CLOUDS FROM THIS
COULD GET INTO SOUTHWESTERN PORTION OF THE LOCAL FORECAST AREA
TONIGHT RESULTING IN LESS RADIATIONAL COOLING THEREFORE WILL NOT
EXTEND FROST ADVISORY ANY FURTHER SOUTH. CUMULUS IN NORTH SHOULD
DISSIPATE AFTER SUNSET SO WILL KEEP FREEZE ADVISORY IN PLACE THERE.
FOR POPS AND QPF HAVE BLENDED NAM12...GFS40...SREF AND ECMWF. WIND
GRIDS GENERATED FROM BLEND OF NAM12 AND GMOS. TEMPERATURE GRIDS
INITIALIZED WITH BIAS CORRECTED GMOS. DEW POINT GRIDS FORM
CMCREG.
-- End Changed Discussion --&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
CLOUDS WILL INCREASE SUNDAY EVENING WITH AN AREA OF SHOWERS
MOVING IN FROM WEST TO EAST OVERNIGHT IN ASSOCIATION WITH A
FRONTAL SYSTEM. FORECAST MODELS ARE STILL STRUGGLING TO RESOLVE
QPF AMOUNTS AND THE EXACT PLACEMENT OF HEAVIER AMOUNTS WITH THE
LATEST NAM FAVORING A MORE NORTHERN SOLUTION WHILE THE GFS IS
FARTHER SOUTH. DECIDED TO USE THE MIDDLE GROUND SOLUTION OFFERED
BY THE GEM REGIONAL FOR QPF SUNDAY NIGHT BUT ALSO ADJUSTED AMOUNTS
DOWN GIVEN THIS MODELS TENDENCY TO HAVE A HIGH BIAS, ESPECIALLY
DURING THE WARM SEASON. SHOWERS WILL CONTINUE INTO MONDAY MORNING
BEFORE DEPARTING FROM WEST TO EAST IN THE AFTERNOON. TOTAL RAIN
AMOUNTS LOOK TO GENERALLY BE IN THE QUARTER TO HALF INCH RANGE
WITH LOCALLY HIGHER AMOUNTS POSSIBLE. HIGHS WILL BE TRICKY FOR
MONDAY AND DEPEND ON HOW QUICKLY CLEARING OCCURS IN THE AFTERNOON.
DID NOT MAKE ANY CHANGES TO PREVIOUS FORECAST SO STILL THINKING
HIGHS GENERALLY IN THE MID TO HIGH 60S, EXCEPT LOW 60S ALONG THE
COAST. HOWEVER EXPECT TEMPERATURES SEVERAL DEGREES COOLER IF
CLEARING IS SLOWER TO OCCUR.

MOST GUIDANCE CONTINUES TO TREND SOUTH WITH THE PLACEMENT OF THE
FRONTAL BOUNDARY FOR MONDAY NIGHT INTO TUESDAY SO ONLY MAINTAINED
CHANCE POPS OVER SOUTHERN AREAS DURING THIS PERIOD WHERE SHOWERS
WILL STILL BE POSSIBLE. NORTHERN AREAS NOW LOOK TO SEE PARTLY
SUNNY SKIES WITH DRY CONDITIONS FOR TUESDAY. EXPECT HIGHS TUESDAY
GENERALLY IN THE LOW TO MID 60S.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
LONGER RANGE MODELS NOW SHOW TUE NGT TO BE FAIR WITH HI CLDNSS
CONFINED TO SW PTNS OF THE FA. WED WILL ALSO BEGIN FAIR...BUT
HI/MID CLDNSS WILL BEGIN TO SPREAD SW TO NE ACROSS ALL OF THE FA
DURG THE DAY AS A S/WV AND SFC LOW SYSTEMS ADVCS ENE FROM THE
MIDWEST...WITH THICKER CLD CVR LAST TO REACH FR NERN PTNS OF THE
FA BY ERLY EVE. SHWRS OR STEADY LGT RN WILL AFFECT SW PTNS OF THE
FA BEGINNING WED EVE...SLOWLY SPREADING INTO THE REST OF THE FA BY
THU. AFTWRDS...LONGER RANGE MODEL SOLUTIONS DVRG WITH THE 12Z GFS
AND CANGEM SOLUTIONS SHOWING SHWRS BEING FORCED BACK S BY A COLD
FRONT PASSAGE THU NGT ALLOWING MSLY FAIR CONDITIONS FOR NRN PTNS
OF THE FA FRI AND SAT...AND CLOUDIER AND MORE UNSETTLED CONDITIONS
ALG THE DOWNEAST COAST. THE 12Z ECMWF...WHICH RAN COUNTER ITS
PRIOR 00Z SOLUTION TAKES ANOTHER S/WV ROTATING ARND A CLOSED
UPPER VORTEX OVR N CNTRL CAN...BRINGING A WV OF SFC LOW PRES SW TO
NE ACROSS THE ST LAWRENCE VLY AND THEN INTO THE NRN MARITIMES
RESULTING IN SHWRY CONDITIONS CONTG THRU ALL OF THE FA ON FRI AS
A COLD FRONT CROSSES THE REGION.

USING THE MODEL BLEND TOOL FOR THE LONG RANGE RESULTED IN KEEPING
SHWRS THU INTO FRI MORN FOR THE SRN HLF OF THE FA...WITH MORE
LONGER RANGE MODELS FAVORING THE GFS SOLUTION ATTM. GIVEN CPC`S
WEEK 2 FCST OF ABV NORMAL TEMPS AND NEAR NORMAL PRECIP WITH OUR FA
NEAR A SPLIT FLOW ALF CONFLUENCE...THE IDEA FOR A STRONG UPPER
TROF APCHG AND CROSSING OUR FA LATE NEXT WEEK AND WEEKEND APPEARS
OVR DONE ATTM. NEVER THE LESS...THERE REMAINS UNCERTAINTY IN THE
FAR XTND...AND WITH SUB-SYNOPTIC AREAS OF SHWRS JUST A LITTLE CHG
IN THE PATTERN OF THE CONSENSUS MODEL PACKAGE WILL MEAN SIG CHGS
TO POPS ACROSS OUR FA DURG THIS TM. SUBSEQUENTLY...HI AND LOW
TEMPS WILL REMAIN UNCERTAIN...WITH THE BEST WE CAN DO ATTM TO
KEEP BOTH NEAR BLENDED ECMWF/GFS ESMNS TO PREVENT TAKING LARGE
FCST BUSTS IN THE EVENT ANY DAY/NGT TM PD ENDS UP OPPOSITE WITH
REGARD TO CLD CVR/RNFL THAN FCST ATTM.

&&

.AVIATION /04Z SUNDAY THROUGH THURSDAY/...
NEAR TERM: VFR CONDITIONS EXPECTED THROUGH SUNDAY.

SHORT TO LONG TERM: EXPECT CONDITIONS DETERIORATING TO MVFR AND
EVENTUALLY IFR SUNDAY NIGHT AS SHOWERS MOVE IN. IFR CONTINUES INTO
MONDAY MORNING BEFORE SOME IMPROVEMENT LIKELY OCCURS IN THE
AFTERNOON, ESPECIALLY NORTH. MVFR CONDITIONS WILL STILL BE
POSSIBLE IN THE SOUTH FOR MONDAY NIGHT INTO TUESDAY WITH VFR
EXPECTED IN THE NORTH DURING THIS TIME. MSLY VFR XPCTD TUE NGT AND
WED THEN MVFR AND PERHAPS EVEN IFR SLOWLY ADVCG S TO N ACROSS THE
TAF SITES WED NGT INTO THU ASSOCIATED WITH LOWERED CLD CVR AND
VSBYS WITH SHWRS.

&&

.MARINE...
NEAR TERM: HAVE BLENDED THE NAM12 AND GFS40 TO INITIALIZE
SUSTAINED WINDS THEN REDUCED THE MODEL BLEND 10 PERCENT DUE TO
PRESENCE OF MARINE LAYER. FOR GUST SPEED HAVE USED 125 PERCENT OF
THE SUSTAINED WINDS. FOR WAVES: WITH LIGHT WINDS EXPECTED THIS
PERIOD EXPECT PRIMARY WAVE SYSTEM FROM INCOMING SWELL. SPECTRAL
INDICATING TWO GROUPS...ONE FROM SOUTHEAST AND ANOTHER SOUTH
SOUTHWEST WITH BOTH GROUPS 1-2 FEET/7-8 SECONDS.

SHORT TO LONG TERM: MARGINAL SCA CONDITIONS WILL BE POSSIBLE BY
LATE SUNDAY NIGHT INTO MONDAY WITH THESE CONDITIONS DIMINISHING
BELOW SCA LEVELS BY LATE MONDAY THROUGH TUESDAY. WVS INCREASE
AGAIN TO JUST BLO SCA CRITERIA ON THU...MSLY IN SWELL.

&&

.CAR WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
ME...FREEZE WARNING UNTIL 7 AM EDT THIS MORNING FOR MEZ001>006.
     FROST ADVISORY UNTIL 7 AM EDT THIS MORNING FOR MEZ011-017-030-032.
MARINE...NONE.
-- End Changed Discussion --

&&

$$
NEAR TERM...CB/KHW/MIGNONE
SHORT TERM...FITZSIMMONS
LONG TERM...VJN
AVIATION...CB/KHW/MIGNONE/FITZSIMMONS
MARINE...CB/KHW/MIGNONE/FITZSIMMONS