FXUS61 KCAR 251925
AFDCAR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CARIBOU ME
225 PM EST FRI DEC 25 2009

.SYNOPSIS...
HIGH PRESSURE WILL BUILD ACROSS THE NORTH TONIGHT THEN SLIDE
SOUTHEAST INTO THE MARITIMES ON SATURDAY. A LARGE AREA OF LOW
PRESSURE WILL LIFT INTO THE GREAT LAKES ON SATURDAY THEN INTO
CANADA SUNDAY WHILE PULLING A WARM FRONT UP INTO THE AREA. A COLD
FRONT WILL FOLLOW SUNDAY NIGHT THEN ANOTHER...STRONGER COLD FRONT
WILL FOLLOW FOR LATER MONDAY NIGHT. A ROUND OF BRISK WINDS AND
MUCH COLDER AIR WILL ARRIVE ON TUESDAY AND REMAIN THROUGH THE
MIDDLE OF NEXT WEEK.
&&

.NEAR TERM /THROUGH SATURDAY/...
STUBBORN LOW-LVL MOISTURE FIELD AND RESULTANT ST/SC DECK REMAIN
THE PRIMARY ISSUE THIS TIME FRAME... SFC OBS AND SAT PIX THRU THE
DAY HAVE SHOWN REMARKABLY LITTLE CHANGE IN THE OVERALL ST/SC CLD
FIELD WHICH COVERS THE ENTIRE FA. HAVE SEEN A LITTLE LIFTING OF THE
DECK (A FEW HUNDRED FEET) DURING THE DAY BUT THAT IS ABOUT IT...
MODELS CONT TO HAVE LITTLE HANDLE ON THIS LOW-LVL MOISTURE FIELD
SO AGAIN TDY WILL BASE THE FCST ON PERSISTENCE.

MOISTURE SEEMS SO LOCKED IN AT THIS POINT THAT IT WILL TAKE A
SIGNIFICANT AIRMASS CHANGE OR INCRS IN THE LOWER LVL WND FIELD TO
GET THINGS MIXING AND BREAKING UP AND DO NOT SEE EITHER HAPPENING
THRU LATE SAT. HGH PRES CURRENTLY RDGD FROM CENTRAL QUEBEC SWRD
ACROSS WRN NEW ENGLAND WILL CREST THE AREA TNGT THEN SHIFT E OF
OUR REGION ERLY SUN. LOW-LVL WND FIELD FCST TO CHANGE FROM LGT
NRLY ATTM TO LGT ERLY ON SUN. MID AND HGH CLDS OVERSPREADING THE
AREA FROM THE SW AHEAD OF THE NXT APPROACHING SYSTEM SHOULD ALSO
HELP CAP THIS LOW-LVL MOISTURE FIELD. END RESULT WILL BE TO KEEP
CLOUDY SKIES ALL AREAS THRU MUCH OF SAT. EVEN LGT DOWN SLOPE FLOW
HAVING LITTLE IMPACT DOWNEAST AREAS SO FAR TODAY...

CLDS WILL KEEP TEMPS UP ACROSS THE AREA TNGT AND HAVE FOLLOWED
PREVIOUS SHIFT THINKING W/ MINS WELL ABV MOS GUIDANCE...
&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
STRONG HIGH PRESSURE WILL BE MOVING TO THE EAST OF NEW ENGLAND AT
THE BEGINNING OF THIS FORECAST PERIOD. WARM AIR ADVECTION WILL
BEGIN DIRECTLY BEHIND THE DEPARTING HIGH AS A STRONG SOUTHERLY
FLOW DEVELOPS IN ADVANCE OF STRONG LOW PRESSURE TO THE WEST OF THE
REGION. PRECIPITATION WILL SPREAD FROM SOUTH TO NORTH LATE
SATURDAY NIGHT AND DURING THE DAY SUNDAY. EXPECT COLD AIR DAMMING
AS WEAK LOW PRESSURE DEVELOPS OVER SOUTHEASTERN NEW
ENGLAND...HOWEVER WARMER AIR WILL DOMINATE ALOFT WITH STRONGEST
SYSTEM WELL TO WEST. SO EXPECT TRANSITION TO MIXED PRECIPITATION.
WILL USE COMBINATION OF OFFICE THICKNESS TOOL AND SURFACE
TEMPERATURE PRECIPITATION TYPE TOOLS. HAVE USED THE NAM12 FOR BOTH
TEMPERATURE AND DEW POINTS. A BLEND OF THE NAM AND GFS USED FOR
POP...SKY AND QPF WITH SOME MANUAL EDITS. THE GMOS WAS USED FOR
WIND.
&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
THE EXTENDED MODELS ARE IN PRETTY GOOD AGREEMENT AT THE START OF
THE LONG TERM. A LOW PRESSURE SYSTEM IN THE SRN GULF OF MAINE
WATERS...A TROUGH OF LOWER PRESSURE EXTENDING ACROSS NRN MAINE.
THIS TROUGH WILL MOVE THROUGH BY TUESDAY MORNING. HIGHER PRESSURE
WILL BUILD IN BEHIND THE TROUGH. THE HIGH WILL CREST OVER THE AREA
WED EVENING TO THUR MORNING. A LOW PRESSURE SYSTEM OVER SRN HUDSON
BAY EARLY THURS MORNING AND ITS ASSOCIATED FRONT WILL MOVE EAST
INTO ERN QUEBEC BY THURS EVENING. FROM THIS POINT THE ECMWF AND
GFS HAVE DIFFERENT SOLUTIONS. THE ECMWF HAS A LOW ALONG THE
PANHANDLE OF FLORIDA THURS MORNING THAT IT DEEPENS AND MOVE NE TO
THE COAST OF NJ BY FRI MORNING. BY THE END OF THE PERIOD THIS LOW
IS SE OF NOVA SCOTIA WITH A OCCLUDED FRONT EXTENDING BACK TO A LOW
OVER THE GREAT LAKES. THE GFS MAINTAINS A WEAK RIDGE OF HIGHER
PRESSURE ACROSS MAINE. THE LOW DEEPENS AND MOVES WELL SOUTH OF
NOVA SCOTIA. THE GFS INDICATES THAT A SECOND LOW WILL MOVE NORTH
OUT OF THE GULF OF MEXICO LATE FRI INTO SAT. BY THE END OF THE
PERIOD THE LOW WILL BE SE OF CAPE COD THE LOW OVER HUDSON BAY WILL
SHIFT EAST AND A COLD FRONT WILL EXTEND ACROSS WRN ME. THE ECMWF
HOWEVER DOES SHOW A SIMILAR PATTERN 24 HRS LATER. LOADED
GMOS...MADE MINOR ADJUSTMENTS FOR SKY AND POP GRIDS. LOADED
NAWAVE4 FOR SEAS.
&&

.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
NEAR TERM: MVFR CIGS ALL TAF SITES AT THIS TIME XCPT HGH IFR AT
KHUL... XPCT LOW MVFR ACROSS THE N TO LOWER BCK TO IFR TNGT W/
PRIMARILY MVFR CONDS CONTG ACROSS OUR SRN TAF SITES. KHUL MAY LIFT
BRIEFLY TO LOW MVFR LATER THIS AFTN BEFORE LOWERING BCK TO IFR
TNGT. GUIDANCE SHOWS VFR ALL TAF SITES BY TOMORROW AFTN BUT BASED
ON PERSISTENCE OF THESE CONDS...WILL LEAN PESSIMISTIC AND HAVE
KEPT OUR SITES BLO VFR THRU 18Z TOMORROW...

SHORT TO LONG TERM: IFR CONDITIONS ARE EXPECTED SATURDAY NIGHT AND
SUNDAY. IMPROVEMENT TO VFR CONDTIONS WILL OCCUR SUNDAY NIGHT AND
PERSIST THROUGH WEDNESDAY.
&&

.MARINE...
NEAR TO SHORT TERM: WNDS/SEAS XPCTD TO REMAIN BLO SCA THRU THE
NEAR TERM PERIOD.

SHORT TO LONG TERM: HAVE USED BLEND OF THE NAM12 AND GFS40 FOR
WIND. FOR WAVES WILL USE WNA/4. LONG FETCH DEVELOPS SOUTHEAST OF
WATERS AHEAD OF THIS SYSTEM SO EXPECT LONG PERIOD WAVES TO
PERSIST. WNA WAVE HEIGHTS LOOK REASONABLE. WILL ISSUE SCA FOR
SATURDAY NIGHT AS WIND AND SEA INCREASE AHEAD OF NEXT SYSTEM.
&&

.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 AM SUNDAY TO 6 AM EST MONDAY FOR 
     ANZ050>052.

&&

$$
NEAR TERM...KHW
SHORT TERM...MIGNONE
LONG TERM...NORTON
AVIATION...KHW
MARINE...KHW/MIGNONE