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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KGYX 111432
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
932 AM EST WED DEC 11 2013

.SYNOPSIS...
A COLD FRONT WILL DROP SOUTH THROUGH THE REGION TODAY THROUGH
TONIGHT. A WEAK RIDGE OF HIGH PRESSURE WILL BUILD IN FROM THE WEST
ON THURSDAY. LOW PRESSURE MOVING EAST THROUGH SOUTHERN QUEBEC
THURSDAY NIGHT WILL SWING A TRAILING COLD FRONT THROUGH THE REGION
ON FRIDAY. HIGH PRESSURE WILL BUILD IN FROM THE NORTHWEST FRIDAY
NIGHT AND SATURDAY. LOW PRESSURE OVER THE OHIO VALLEY SATURDAY
NIGHT WILL REDEVELOP OFF THE MID ATLANTIC COAST AND WILL MOVE
NORTHEAST OFF THE NEW ENGLAND COAST ON SUNDAY. LOW PRESSURE WILL
CONTINUE NORTHEAST INTO THE MARITIMES SUNDAY NIGHT. HIGH PRESSURE
WILL BUILD IN FROM THE WEST ON MONDAY THEN SHIFT OFFSHORE ON
TUESDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
UPDATE...
HAVE UPDATED THE GRIDS BASED ON CURRENT CONDITIONS. ALLOWED FOR
GREATER WINDS FOR THE HIGHER TERRAIN AND INCREASED POPS TO BETTER
MATCH WFO BTV FOR THE UPSLOPE SNOWS THAT WILL LIKELY OCCUR THIS
AFTERNOON AND EVENING IN ASSOCIATION WITH THE ARCTIC FRONT. SHOULD
SEE A QUICK 2-4 INCHES OF SNOW IN THE MOUNTAINS WITH THIS FEATURE.

OTHERWISE...ONLY MINIMAL CHANGES TO THE GRIDDED PACKAGE BASED ON
CURRENT OBSERVATIONS.

PREV DISC...
ANOTHER SHOT OF ARCTIC AIR ON THE WAY FOR THE NORTHEAST
TODAY AS A COLD FRONT DROPS SOUTH FROM CANADA. WILL SEE INCREASING
CLOUDS THIS MORNING IN NORTHERN ZONES AND SOME OF THIS CLOUDINESS
WILL SETTLE INTO SOUTHERN ZONES LATE THIS AFTERNOON AND THIS
EVENING. WILL LIKELY SEE SNOW SHOWERS AND SOME SQUALLS IN THE
MOUNTAINS TODAY AND THERE`S A CHANCE SOME OF THESE WILL DRIFT INTO
SOUTHERN ZONES LATER THIS AFTERNOON AND THIS EVENING. FRONT WILL
BE RATHER MOISTURE STARVED BUT AN INCH OR SO OF ACCUMULATION WILL
BE POSSIBLE IN THE NORTH. HIGH TEMPS WILL ONLY REACH THE LOWER TO
MID 20S NORTH AND MID 20S TO LOWER 30S SOUTH.
-- End Changed Discussion --

&&

.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
COLD FRONT WILL PUSH SOUTH OF THE REGION OVERNIGHT WITH CLOUDS AND
ANY LINGERING FLURRIES CLEARING OUT AFTER MIDNIGHT AS HIGH
PRESSURE BUILDS IN FROM THE WEST. WILL SEE OVERNIGHT LOWS ONCE
AGAIN WELL BELOW NORMAL WITH NORTHERN ZONES BOTTOMING OUT AT ZERO
TO 5 BELOW. TEMPERATURES IN CENTRAL AND SOUTHERN AREAS WILL RANGE
THROUGH THE SINGLE NUMBERS TO LOWER TEENS.

THURSDAY LOOKING FAIR AS HIGH PRESSURE CRESTS OVER THE REGION.
WILL SEE SOME CLOUDS SPILLING IN FROM THE WEST IN THE AFTERNOON
AS A WEAK SYSTEM CROSSING SOUTHERN CANADA APPROACHES FROM THE
WEST. DESPITE SUNSHINE AND LIGHT WINDS TEMPERATURES WILL BE HARD
PRESSED TO MAKE IT OUT OF THE SINGLE NUMBERS AND LOWER TEENS IN
THE NORTH. HIGHS IN THE SOUTH WILL RANGE FROM THE MID TEENS TO
LOWER 20S.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
-- Changed Discussion --
WEAK RIDGE OF COLD HIGH PRES OVER THE REGION EXITS QUICKLY TO THE E
THURSDAY NGT AS A WEAK TROF OF LOW PRES MOVES THRU FRIDAY ASSOCIATED
WITH A STRONG UPR LVL JET. THIS SYSTEM MAY SQUEEZE OUT A FEW -SHSN
     ESPECIALLY ACROSS THE MOUNTAINS LATE THURSDAY NGT THRU MIDDAY
FRIDAY. HIGH PRESSURE NOSES IN FROM THE GREAT LAKES AND SOUTHERN
CANADA FRIDAY NGT AND SATURDAY BRINGING FAIR SKIES BUT CONTINUING
THE COLD WX. EVEN WITH BELOW NORMAL TEMPS THURSDAY NGT THRU SATURDAY
THE CORE OF THE ARCTIC AIR MASS STAYS TO OUR NORTH.

MODELS CONT TO SHOW A SHORT WAVE LIFTING NE ALONG THE E COAST
SATURDAY NGT AND SUNDAY WITH LOW PRES ALSO TRACK NE FROM THE MID
ATLANTIC COAST...TRACKING INSIDE 40N 70W LAT/LON BENCHMARK FOR HEAVY
SNOW EVENT FOR OUR FCST AREA PER THE GFS WHILE THE ECMWF IS NOW A
LITTLE FURTHER OUT TO SEA...GOING RIGHT OVER 40N 70W...THEN MOVING
MORE TO THE ENE THAN NE. SOME WARM AIR TRIES TO INTRUDE INTO EXTREME
SE NH AND THE SW COAST OF MAINE WHERE SOME MIX IS POSSIBLE...BUT
WITH HIGH PRES LOCKED IN TO THE N PROVIDING COLD AIR FUNNELING
SOUTHWARD INTO THE FCST AREA ON N NE SFC WINDS EXPECT THAT ANY MIXED
PRCP WOULD BE SLEET OR MAYBE SOME FREEZING RAIN...BUT NOT RAIN.
CURRENT TRENDS SUGGEST A SIGNIFICANT SNOW EVENT IS POSSIBLE FOR THE
FCST AREA...DEVELOPING SATURDAY NGT THEN ENDING SUNDAY AFTERNOON OR
EVENING. STILL PLENTY OF TIME FOR TRACK, INTENSITY AND TIMING TO
CHANGE AS MODELS ARE KNOWN TO DO.

THE LOW INTENSIFIES AS IT MOVES OVER THE MARITIMES WITH A STRONG NW
FLOW USHERING IN VERY COLD CANADIAN AIR FOR SUNDAY NGT AND MONDAY.
HIGH PRES BUILDS WITH VERY COLD BUT DRY WX ON MONDAY. A STRONG UPR
LVL SYSTEM MOVING INTO THE GREAT LAKES REGION ON TUESDAY PUSHES A
SFC LOW AND ASSOCIATED WARM FNT/COLD FNT TOWARD THE E COAST WHICH
WILL SPREAD CLOUDS AND PRCP INTO THE REGION. STILL WAY TOO EARLY TO
DETERMINE THE TIMING AND STRENGTH OF THIS SYSTEM OR HAVE HIGH
CONFIDENCE ON PRCP TYPE.

USED A BLEND OF MODELS AND MOS GUIDANCE ALONG WITH HPC QPF FOR
PERIODS 4 AND 5...THEN USED A SUPER BLEND OF VARIOUS MODELS AND MOS
GUIDANCE ...ALONG WITH BIAS CORRECTED GUIDANCE AND THE PREVIOUS
FORECAST FOR DAYS 4 THRU 8.
-- End Changed Discussion --

&&

.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM...VFR TODAY WITH AREAS OF MVFR CEILINGS AND VSBY
POSSIBLE IN THE MOUNTAINS IN ANY SNOW SHOWERS. VFR TONIGHT AND
THURSDAY.

LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...WEAK TROF OF LOW PRES
MAY PRODUCE MVFR CIG/VSBY FRIDAY IN -SHSN... MORE SO OVER THE
MOUNTAINS. COASTAL LOW MAY PROVIDE A HEAVY SNOW EVENT LATE
SATURDAY NGT AND SUNDAY WITH IFR/LIFR CONDITIONS.

&&

.MARINE...
SHORT TERM...UPGRADING SCA`S TO GALES FOR THE OUTER WATERS THROUGH
MIDNIGHT TONIGHT. CONTINUING SCA`S FOR THE BAYS.

LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...CONDITIONS BELOW SCA
LEVELS THURSDAY NGT UNDER WEAK HIGH PRESSURE. WEAK TROF OF LOW
PRESSURE MOVES THRU FRIDAY BUT A WESTERLY FLOW SETS UP WITH STRONG
WESTERLY FLOW ALOFT THAT MIXES DOWN AND MAY PRODUCE SCA LEVEL
WINDS. HIGH PRES BUILDS BACK IN FRIDAY NGT AND SATURDAY. THE WAVE
HEIGHT GUIDANCE APPEARS TOO HIGH FOR LATE THURSDAY NGT THRU
SATURDAY WITH WEAK PRES PATTERN...MOSTLY OFFSHORE FLOW AND NO BIG
STORMS ANYWHERE OVER THE ATLANTIC TO GENERATE SWELLS FOR OUR
COASTAL WATERS. SEAS WILL COME UP SOME ON GUSTY W WINDS FRIDAY BUT
OFFSHORE FLOW WILL OFFSET THAT TO KEEP SEAS MOSTLY BELOW THE 5 FT
SCA THRESHOLD. A COASTAL LOW MAY BRING STRONG GALES LATE SATURDAY
NGT AND SUNDAY. FOR NOW SHOWING GALE FORCE GUSTS OVER THE OUTER
WATERS. SEAS SHOULD BUILD SIGNIFICANTLY IN RESPONSE TO THE
STRENGTHENING LOW PRES SYSTEM PER WNA4 GUIDANCE.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 AM EST THURSDAY FOR ANZ151-153.
     GALE WARNING UNTIL 1 AM EST THURSDAY FOR ANZ150-152-154.

&&

$$