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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KGYX 100041
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
741 PM EST MON DEC 9 2013

.SYNOPSIS...
WEAK LOW PRESSURE WILL TRACK NORTH-NORTHEAST THROUGH THE GULF OF
MAINE THIS EVENING. A COLD FRONT WILL CROSS THE REGION TONIGHT
FOLLOWED BY A WEAK RIDGE OF HIGH PRESSURE ON TUESDAY. A SECONDARY
COLD FRONT WILL APPROACH FROM THE NORTHWEST ON WEDNESDAY AND WILL
SLOWLY SINK SOUTH THROUGH THE REGION WEDNESDAY NIGHT. HIGH
PRESSURE WILL GRADUALLY BUILD IN FROM THE WEST THURSDAY THROUGH
FRIDAY. A BACKDOOR COLD FRONT WILL CROSS NORTHERN NEW ENGLAND ON
SATURDAY. LOW PRESSURE WILL MOVE EAST THROUGH THE REGION SATURDAY
NIGHT AND INTO THE MARITIMES BY SUNDAY MORNING.

&&

.NEAR TERM /TONIGHT/...
-- Changed Discussion --
730PM UPDATE...
WIDESPREAD AREAS OF FREEZING DRIZZLE THIS EVENING... WITH 00Z GYX
SOUNDING SUPPORTING FREEZING DRIZZLE. HOWEVER... SOME AREAS OF
PECULIAR SNOW SHOWERS STILL PERSIST ACROSS MUCH OF INTERIOR WESTERN
MAINE AND EAST CENTRAL NEW HAMPSHIRE. CURRENT THINKING REGARDING
THIS IS THAT AN EASTERLY SURFACE WIND OVER THE WATERS IS
TRANSPORTING MOISTURE UP AND OVER THE COASTAL FRONT... TWISTING TO
THE NORTH AS IT DOES SO. THIS MOIST AIR IS FORCED TO RISE...
PRODUCING CONDENSATION AND PRECIPITATION. HOWEVER... ADD TO THIS A
SOUTHWEST FLOW IN THE 850 TO 700 MB LAYER ABOVE THE LOW LEVEL
INVERSION. THIS CREATES LOW LEVEL SHEAR... LEADING TO A BANDED
STRUCTURE TO THE SNOW SHOWERS... DRIFTING OFF TO THE NORTHEAST
WITH THE MID LEVEL FLOW. CURRENTLY FREEZING DRIZZLE IS WIDESPREAD
TO THE EAST OF THE MOUNTAINS... WITH THE COASTAL FRONT HAVING
PUSHED OFFSHORE EXCEPT FOR ALONG THE MIDCOAST VERY CLOSE TO SHORE.
SNOW ONLY EXISTS WITHIN THE ECHOES SEEN ON RADAR FROM THE BANDED
SHOWERS AND HAVE DECIDED TO ORIENT THE POP STRUCTURE TO CORRESPOND
TO WHERE THESE SHOWERS ARE EXPECTED TO DRIFT FOR THE NEXT SEVERAL
HOURS. EXPECT THIS ENTIRE AREA OF SNOW SHOWERS TO SHIFT TO THE
EAST AS THE LOW LEVEL FLOW SHIFTS TO THE WEST... CUTTING OFF THE
SOURCE OF MOISTURE. EXPECT FREEZING DRIZZLE TO ALSO END AS THIS
OCCURS... THEREFORE WILL LET ADVISORIES EXPIRE FROM WEST TO EAST
THIS EVENING... 10 PM IN NEW HAMPSHIRE... AND MIDNIGHT IN MAINE.
ONLY TRACE AMOUNTS OF ICE ARE EXPECTED... ALONG WITH AN ADDITIONAL
INCH OR SO OF SNOWFALL WITHIN THE INLAND SNOW SHOWERS.

430PM UPDATE...
HAVE ADJUSTED POP FORECAST TO SHOW AREAS OF SNOW/RAIN ONGOING FROM
PORTLAND NORTHEASTWARD. SOUTH OF HERE... SOME AREAS OF FREEZING
RAIN HAVE DEVELOPED. WINDS HAVE SHIFTED TO NORTHWEST AT PORTLAND
WITH TEMPERATURES FALLING. COASTAL FRONT HAS PUSHED TO THE
IMMEDIATE COASTLINE AND EXPECT THIS TO HOLD STEADY OR SLOWLY PUSH
EAST OVER THE NEXT FEW HOURS. FREEZING RAIN SOUTHWEST OF PORTLAND
IS A RESULT OF LACK OF ICE NUCLEI IN THE LOW LEVEL PRECIPITATION-
GENERATING CLOUD LAYER. ANY ACCUMULATIONS FROM THIS SHOULD BE
LIGHT. EXPECT AN ADDITIONAL INCH OR SO OF SNOW NORTHEAST OF
PORTLAND THIS EVENING BEFORE TRANSITIONING TO FREEZING RAIN AND
THEN CLEARING.

ORIGINAL DISCUSSION...
THE COASTAL FRONT REMAINED DRAPED ALONG THE ROUTE ONE CORRIDOR AT
19Z. THE STEADIER MIXED PRECIPITATION WILL TAPER TO EITHER LIGHT
DRIZZLE OR FREEZING DRIZZLE THIS EVENING DEPENDING ON SURFACE
TEMPERATURES. ALONG THE COAST...TEMPERATURES SHOULD BE ABOVE
FREEZING THIS EVENING WITH DRIZZLE WHILE WE`LL SEE SOME AREAS OF
FREEZING DRIZZLE ACROSS THE INTERIOR. FOR THE REMAINDER OF THE
OVERNIGHT...THE DRIZZLE SHOULD END AND WE`LL BE LEFT WITH MOSTLY
CLOUDY SKIES. THE ADVISORY REMAINS IN EFFECT INTO TONIGHT FOR AN
ADDITIONAL 1 TO 2 INCHES OF SNOW AND OR SOME LIGHT ICING IN
FREEZING DRIZZLE.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
ON TUESDAY...LOW PRESSURE PASSES TO OUR EAST AND WELL OFFSHORE
ALTHOUGH THE AREA WILL BE ON THE WESTERN PERIPHERY OF THE CLOUD
BAND WITH SOUTHERN AND EASTERN SECTIONS PERHAPS BRUSHED BY A FEW
FLURRIES. OTHERWISE...THE COLD WESTERLY FLOW DOWNWIND OF THE GREAT
LAKES MAY ALLOW A FEW SNOW SHOWERS TO REACH INTO THE CONNECTICUT
VALLEY AND WHITE MOUNTAINS.

FOR TUESDAY NIGHT...SOME LAKE EFFECT STREAMERS CONTINUE TO SPREAD
A FEW CLOUDS AND SCATTERED SNOW SHOWERS INTO THE CONNECTICUT
VALLEY AND WHITE MOUNTAINS. ELSEWHERE...MAINLY CLEAR WITH A FEW
OCEAN EFFECT CLOUDS AND SNOW SHOWERS POSSIBLE ACROSS OUR OUTER
COASTAL WATERS IN THE DEEPENING COLD AIR.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
A WEAK CLIPPER-TYPE SYSTEM WILL CROSS THE FORECAST AREA ON
WEDNESDAY. THIS WILL BRING SCATTERED SNOW SHOWERS AND FLURRIES TO
THE REGION...WITH THE GREATEST LIKELIHOOD IN THE MOUNTAINS. A COLD
NORTHWEST FLOW WILL FOLLOW ON THURSDAY...WHEN UPSLOPE SNOW SHOWERS
MAY ACCUMULATE OVER THE HIGHER TERRAIN.

A WARM AIR ADVECTION PATTERN WILL BRING QUITE A FEW CLOUDS TO THE
REGION ON FRIDAY. A FRONT WILL RETURN AS A BACKDOOR COLD FRONT BY
SATURDAY AS HIGH PRESSURE BUILDS SOUTH FROM CANADA. THIS COLD AIR
SETS THE STAGE FOR THE NEXT WEATHER SYSTEM EXITING OUT OF THE
SOUTHEASTERN UNITED STATES. ALL GUIDANCE NOW DEPICTING LOW
PRESSURE MOVING EITHER THROUGH THE GULF OF MAINE OR JUST SOUTH OF
THE REGION EARLY SUNDAY MORNING. THIS WILL LIKELY BRING ADDITIONAL
SNOWFALL AND PERHAPS MIXED PRECIPITATION TO SOUTHERN AREAS OVER
THE WEEKEND.

&&

.AVIATION /01Z TUESDAY THROUGH SATURDAY/...
SHORT TERM...MVFR AND AREAS OF IFR IN MIXED PRECIPITATION
IMPROVING TO VFR THROUGHOUT BY 12Z. SCATTERED MVFR POSSIBLE
TUESDAY AND TUESDAY NIGHT AT KLEB AND KHIE IN SNOW SHOWERS.

LONG TERM...AREAS OF MVFR CEILINGS AND VISIBILITY MAINLY IN
NORTHERN ZONES WEDNESDAY...THURSDAY AND SATURDAY.

&&

.MARINE...
SHORT TERM...MARGINAL SMALL CRAFT CONDITIONS ARE LIKELY TO LINGER
OUTSIDE THE BAYS INTO TUESDAY AHEAD OF AND IN THE WAKE OF A WEAK
SURFACE LOW THAT CROSSES THE WATERS TONIGHT.

LONG TERM...SCA`S LIKELY WEDNESDAY. SCA`S POSSIBLE AGAIN ON
THURSDAY.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
ME...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR
     MEZ007>009-012>014-018>028.
NH...WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
     NHZ004-006-008>010-013-014.
MARINE...SMALL CRAFT ADVISORY UNTIL 3 PM EST TUESDAY FOR ANZ150>154.
-- End Changed Discussion --

&&

$$

NEAR TERM UPDATE... KIMBLE