FXUS61 KCAR 250750
AFDCAR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CARIBOU ME
250 AM EST FRI DEC 25 2009

.SYNOPSIS...
HIGH PRESSURE WILL BUILD ACROSS THE NORTH TODAY AND 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 TONIGHT/...
LOW ST/SC CLD CVR WILL CONT TO BE THE CHALLENGE TDY AND TNGT...WITH
GRIDDED MODEL CLD DATA NOT MUCH HELP WITH THE NEAR TERM SKY CVR.
ALTHOUGH A STRONG SFC HI PRES RIDGE WILL BE ADVANCING TDY AND
CRESTING THE REGION TNGT...THE PROBLEM IS THAT A STRONG 900-800 MB
SUBSIDENCE INVERSION IS FCST TO REMAIN INTACT TDY AND ONLY WEAKEN
SOMEWHAT TNGT. THIS IMPLIES THAT LOW LVL MOISTURE AOB 900 MB LEFT
BEHIND FROM THE LAST STORM SYSTEM WILL HAVE LITTLE OPPORTUNITY TO
BE VENTED OUT PARTICULARLY OVR NRN PTNS OF THE FA. THE SRN
HLF...WHERE THE MOISTURE LAYER IS THINNER AND WHERE THERE IS SOME
DOWNSLOPE COMPONENT TO THE SFC WIND SHOULD SEE AT LEAST SOME BREAK
OUT FROM THE LOW CLDS BY THIS AFT. STATISTICAL TAF...BUFKIT AND LLVL
RH FIELDS BLO AOB 925 MB INDICATE LOW CLDS FILLING BACK IN ACROSS
MUCH OF THE FA FRI EVE. ALTHOUGH CLD CVR IS RELATIVELY THIN...CANNOT
RULE OUT A FEW FLURRIES AT LEAST THRU THE MORN ACROSS THE N. A
RELATIVELY MILD AIR MASS FOR THIS TIME OF SEASON WILL RESULT IN
ABV NORMAL HI TEMPS...EVEN ACROSS NRN AREAS WHERE SUNSHINE WILL BE
AT A PREMIUM. LOW TEMPS TNGT WILL BE SPCLY CHALLENGING WITH THE
THREAT OF LOW CLD CVR SHARPLY REDUCING RADIATIONAL COOLING POTENTIAL.
SUBSEQUENTLY...WE MODIFIED OVRNGT LOWS UPWARDS TO REFLECT THIS
UNCERTAINTY.
&&

.SHORT TERM /SATURDAY THROUGH SUNDAY/...
HIGH PRESSURE NORTHEAST OF THE REGION WILL BRING A PARTLY CLOUDY
SKY TO THE AREA ON SATURDAY...THOUGH SOME LOW CLOUDS MAY BEGIN TO
ADVANCE INTO DOWNEAST AREAS. CLOUDS WILL INCREASE SATURDAY NIGHT
AS THE HIGH SLIPS SOUTHEASTWARD INTO THE MARITIMES AS AN
INCREASINGLY MOIST SOUTHEAST FLOW OF AIR MOVES IN BEHIND THE HIGH
AND AHEAD OF AN ADVANCING OCCLUDING FRONT. SNOW...SLEET AND
FREEZING RAIN ARE THEN EXPECTED TO MOVE IN ON SUNDAY. PRECIP WILL
QUICKLY TURN OVER TO RAIN DOWNEAST BUT MAY CONTINUE AS SNOW...
SLEET AND FREEZING RAIN THROUGH MIDDAY SUNDAY UP NORTH BEFORE
WARMER AIR CHANGES PRECIP TO PLAIN RAIN. ONE FORECAST CONCERN IS A
SECONDARY WAVE OF LOW PRESSURE FORMING ALONG THE FRONT. THIS COULD
HOLD COLD AIR IN FOR A BIT LONGER UP NORTH RESULTING IN AN
EXTENDED PERIOD OF SNOW OR SLEET INTO SUNDAY AFTERNOON. HOWEVER...
GUIDANCE INDICATES THAT BY THE END OF THE DAY PRECIP SHOULD BE
MAINLY RAIN OVER THE ENTIRE ARE...EXCEPT FOR SOME POCKETS OF
FREEZING RAIN OVER THE FAR NORTH.
&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
THE OCCLUDING FRONT WILL LIFT NORTHEAST OUT OF THE AREA SUNDAY
NIGHT AS COOLER AIR MOVES IN FROM THE WEST. A MUCH MORE POWERFUL
COLD FRONT WILL APPROACH MONDAY NIGHT AND MOVE THROUGH LATE 
MONDAY NIGHT. THE POSSIBILITY OF A SMALL WAVE OF LOW PRESSURE
FORMING ALONG THIS FRONT MAY BRING SOME SNOW SHOWERS AND SQUALLS
LATE AT NIGHT BEFORE MUCH COLDER AIR MOVES IN BEHIND THE FRONT
ON TUESDAY. WEDNESDAY AND THURSDAY WILL BE COLD...AND MAINLY 
DRY EXCEPT FOR SOME LIGHT SNOW SHOWERS OR FLURRIES ACROSS THE
NORTH. 
&&

.AVIATION /05Z FRIDAY THROUGH TUESDAY/...
NEAR TERM: IFR CLGS NRN TAF SITES TO LOW MVFR DOWNEAST SITES
SHOULD TRANSITION TO HI MVFR NRN TAF SITES AND VFR DOWNEAST SITES
THIS AFT. CLGS MAY LOWER AT LEAST BACK TO MVFR ALL SITES TNGT. 

SHORT TO LONG TERM: VFR CONDITIONS ON SATURDAY MAY LOWER TO MVFR
AS LOW CLOUDS MOVE IN DOWNEAST LATE SATURDAY. MVFR CONDITIONS
SHOULD LOWER TO IFR SATURDAY NIGHT AS LOW CLOUDS MOVE UP FROM THE
SOUTH...AND REMAIN IFR ON SUNDAY. CONDITIONS MAY IMPROVE TO MVFR
DOWNEAST SUNDAY NIGHT AS DRIER AIR MOVES IN. IFR TO MVFR
CONDITIONS UP NORTH AND MVFR TO VFR CONDITIONS DOWNEAST ARE
THEN EXPECTED MONDAY INTO TUESDAY AS A COLD FRONT MOVES THROUGH.
&&

.MARINE...
NEAR TO SHORT TERM: NO HDLNS ANTICIPATED TDY AND TNGT WITH
SLACKENING WIND FIELD WITH THE SFC RIDGE AXIS APCHG TDY AND
CRESTING TNGT. WINDS AND SEAS WILL SLOWLY BUILD SAT THRU SAT
NGT (SCA RANGE) IN ADV OF LOW PRES DEVELOPING OVR THE MID ATLC
STATES.

SHORT TO LONG TERM: GALE WARNINGS MAY BE NEEDED FOR STRONG
SOUTHEAST WINDS ON SUNDAY AND AGAIN FOR COLD GUSTY NORTHWEST
WINDS ON TUESDAY.
&&

.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.

&&

$$
NEAR TERM...VJN
SHORT TERM...BLOOMER
LONG TERM...BLOOMER
AVIATION...VJN
MARINE...VJN/BLOOMER