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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KGYX 300250
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
950 PM EST THU JAN 29 2015


.SYNOPSIS... ANOTHER STORM SYSTEM WILL BRING A PERIOD OF MODERATE
TO HEAVY SNOWFALL TO THE AREA LATE TONIGHT THROUGH EARLY SATURDAY.
HIGH PRESSURE FOLLOWS OVER THE WEEKEND...WITH ANOTHER SYSTEM
MOVING SOUTH OF NEW ENGLAND ON MONDAY. HIGH PRESSURE WILL FOLLOW
MIDWEEK. LOW PRESSURE WILL PASS BY TO OUR SOUTH ON THURSDAY.

&&

.NEAR TERM /TONIGHT/...
-- Changed Discussion --
950 PM UPDATE...UPDATED THE FORECAST TO SLOW THE EASTWARD
PROGRESSION OF LIGHT SNOW THIS EVENING...BASICALLY DELAYING IT
A FEW HOURS DUE TO THE PRESENCE OF LOW LEVEL DRY AIR. OTHERWISE...
NOT SIGIFICANT CHANGES.

725 PM UPDATE...NO MAJOR CHANGES TO THE GOING FORECAST. HAVE UPDATED
TEMPERATURES AND POPS BASED ON LATEST TRENDS IN OBSERVATIONAL DATA.

PREVIOUSLY...

LOOK FOR CLOUDS TO OVERSPREAD THE CWA THIS
EVENING...WITH SNOW BREAKING OUT FROM W-E AFTER MIDNIGHT AS CLIPPER
SYSTEM TRACKS EWD OUT OF THE GREAT LAKES AND INTO NEW ENGLAND. PARTS
OF NH COULD SEE UP TN INCH OR SO BY THE MORNING COMMUTE...BUT BULK
OF SNOWFALL WILL HOLD OFF UNTIL LATER IN THE MORNING. MINS TONIGHT
WILL DROP OFF SOMEWHAT THIS EVENING...MORE SO IN THE EAST...WHERE
SKIES WILL BE CLEAR A LITTLE LONGER...BUT SW ABV THE BOUNDARY LYR
AND A WEAK ONSHORE FLOW SHOULD START SET TEMPS ON THE RISE AFTER
MIDNIGHT...ESPECIALLY IN COASTAL AREAS.
-- End Changed Discussion --

&&

.SHORT TERM /6 PM FRIDAY AND FRIDAY NIGHT/... 500MB TROUGH
ASSOCIATED WITH THE CLIPPER MOVES INTO THE ERN CONUS AND PHASES
WITH SRN STREAM WAVE WHILE GETTING REINFORCING SHOT OF ENERGY FROM
UPSTREAM. THIS WILL TILT THE TROUGH NEG AND CLOSE IT OFF THE 500
MB LOW ALLOWING SFC LOW TO INTENSIFY AND MID LVL SYSTEM TO CLOSE
OFF. THIS WILL GENERATE SOME DEFORMATION AND BANDING FRI AFTERNOON
AND EVE ACROSS ME...WHICH WILL LKLY SPILL OVER INTO ERN NH. THE
12Z MODEL SUITE...OVERALL SHOWED MORE QPF...AND HAVE THUS SNOW
AMTS HAVE INCREASED AS WELL...AND EXPANDED THE WARNING INTO ERN
NH. HEAVIEST SNOW WOULD BE FOUND N AND E OF PORTLAND FROM FRI
AFT THRU FRI EVENING WHERE 8-12" WILL BE COMMON WITH LOCALLY
HIGHER AMTS. THE BANDING COULD PRODUCE SNOWFALL RATES OF 1-2"
HOUR. THRU THE STORMS WINDS WILL GENERALLY BE LIGHT...BUT NW FLOW
BEHIND THE SYSTEM WILL PICK UP LATE FRI NIGHT AND COULD PRODUCE
SOME BLOWING AND DRIFTING.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
LOW PRESSURE CONTINUES RAPID CYCLOGENESIS ON SATURDAY ALONG THE
EASTERNMOST PORTIONS OF THE GULF OF MAINE AS IT EXITS INTO THE
CANADIAN MARITIMES. SNOW WILL WIND DOWN OVER EASTERN SECTIONS.
CLEARING...BREEZY AND COLD CONDITIONS TO FOLLOW.

12Z MODEL SUITE IS THEN IN BETTER AGREEMENT DEPICTING A
REINFORCING SHOT OF COLD AIR ASSOCIATED WITH AN ARCTIC FRONT
CROSSING THROUGH THE REGION DURING THE MIDDAY AND EARLY AFTERNOON
HOURS. MODELS ARE ALSO CONVERGING ON A SOLUTION THAT A WAVE OF LOW
PRESSURE WILL MOVE ALONG THIS FRONT WHICH WILL BE SITUATED OVER
THE MID ATLANTIC REGION. THIS IS FURTHER SOUTH THAN PREVIOUS RUNS.

HIGH PRESSURE TO QUICKLY FOLLOW THIS PROGRESSIVE AND POSITIVELY
TILTED SYSTEM. THE NEXT FRONTAL SYSTEM WILL CROSS OUR REGION
WEDNESDAY NIGHT.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
SHORT TERM...VFR THIS EVE DETERIORATES TO IFR OR LOWER AT TIMES
IN SN AND LOW CIGS...PERSISTING INTO FRI NIGHT. SOME IMPROVEMENT
MAY BE POSSIBLE LATE FRI NIGHT IN KLEB/KHIE/KHIE...BUT WILL HAVE
TO WAIT UNTIL SAT MOST EVERYWHERE ELSE.

LONG TERM...CONDITIONS WILL IMPROVE TO VFR ACROSS ALL AIRPORTS
SATURDAY AND REMAIN VFR THROUGH THE WEEKEND.

&&

.MARINE...
SHORT TERM...WATER WILL BE QUIET THROUGH THE DAY FRIDAY...BUT NW
FLOW WILL START TO INCREASE FRI EVE...WITH GALES EXPECTED AFTER
MIDNIGHT.

LONG TERM...GALES WILL LIKELY CONTINUE INTO SATURDAY.
&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WINTER STORM WARNING FROM 1 AM FRIDAY TO 6 AM EST SATURDAY FOR
     MEZ007-008-012-013-018>020-023-024.
     WINTER STORM WARNING FROM 3 AM FRIDAY TO 10 AM EST SATURDAY
     FOR MEZ009-014-021-022-025>028.
NH...WINTER STORM WARNING FROM 1 AM FRIDAY TO 6 AM EST SATURDAY FOR
     NHZ001-002-004-006-009-010-013-014.
     WINTER WEATHER ADVISORY FROM 11 PM THIS EVENING TO 6 AM EST
     SATURDAY FOR NHZ003-005-007-008-011-012-015.
MARINE...GALE WATCH FROM LATE FRIDAY NIGHT THROUGH LATE SATURDAY NIGHT
     FOR ANZ150>154.

&&

$$

NEAR TERM UPDATE...MLE
NEAR TERM...CEMPA
SHORT TERM...CEMPA
LONG TERM...CANNON