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000
FXUS61 KGYX 250937
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
437 AM EST SUN JAN 25 2015

.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS THE WATERS THIS MORNING. LOW
PRESSURE WILL BEGIN TO DEVELOP OFF THE MID ATLANTIC COAST ON
MONDAY THEN RAPIDLY DEVELOP AS IT MOVES NORTHEASTWARD TO JUST
SOUTH OF NANTUCKET MASSACHUSETTS ON TUESDAY. THE LOW WILL LINGER
AROUND THROUGH WEDNESDAY BRINGING A SIGNIFICANT SNOWFALL TO OUR
REGION. THERE IS ALSO THE POTENTIAL FOR ANOTHER STORM LATE WEEK OR
EARLY IN THE WEEKEND BUT CONFIDENCE IS LOW AT THIS TIME.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A COLD FRONT WILL MOVE ACROSS THE REGION THIS MORNING BRINGING A
PERIOD OF CLOUDS AND ALSO A CHANCE OF SNOW SHOWERS...MAINLY ACROSS
THE INTERIOR. A FEW HEAVIER SQUALLS MAY BE EMBEDDED.
THEREAFTER...JUST COLD AND WINDY FOR THE BALANCE OF THE DAY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
COLD NIGHT ON TAP TONIGHT AS HIGH PRESSURE BUILDS INTO THE REGION.
WIND CHILLS MAY APPROACH 20 BELOW ZERO FOR A TIME ACROSS FAR
NORTHERN REACHES OF OUR CWA. HOWEVER...ELECTED TO NOT ISSUE A
WIND CHILL ADVISORY AT THIS TIME DUE TO SPORADIC COVERAGE...MAINLY
AT HIGHER ELEVATIONS.

INCREASING HIGH CLOUDS ON MONDAY AS STORM SYSTEM WELL TO OUR SOUTH
STARTS TO GET UNDERWAY. IT SHOULD REMAIN DRY THROUGHOUT THE DAY.


&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MAIN FOCUS OF THE EXTENDED IS ON STRONG LOW PRES FORECAST TO
DEVELOP S OF NEW ENGLAND MON INTO TUE.

STRONG S/WV TROF EXITING THE CANADIAN PRAIRIES TODAY WILL DEPART
THE MID ATLANTIC COAST BY MON AFTERNOON. UPON REACHING THE RICH
BAROCLINICITY OFFERED BY THE WARM ATLANTIC...THIS LOW PRES WILL
RAPIDLY DEVELOP S OF NEW ENGLAND. DROPPING SOME 20 MB IN 24 HOURS
THIS WILL BRING SIGNIFICANT IMPACTS TO THE REGION. THE INITIAL
S/WV IS FORECAST TO DIG S TOWARDS THE CAROLINAS. THIS ALLOWS TIME
FOR THE UPSTREAM KICKER TO CATCH UP AND PHASE WITH THE DEVELOPING
SYSTEM LATE MON. THIS WILL ACT TO SLOW DOWN...STALL...AND PERHAPS
LOOP THE LOW PRES S OF NEW ENGLAND...PROLONGING IMPACTS AS WELL.

CONSIDERING HOW DYNAMIC THE SYSTEM IS...MODEL CLUSTERING ON QPF
IS FAIRLY TIGHT. DETERMINISTIC MODELS ALL BRING AT LEAST 0.60
INCHES QPF TO THE INTERNATIONAL BORDER. GEFS AND ECMWF EPS ALSO
BRING THE HALF INCH QPF LINE N OF THE BORDER. THIS IS A ROBUST
SIGNAL FOR SOME MODERATE TO HEAVY ACCUMULATIONS THRU THE ENTIRE
FORECAST AREA. DURING THE RAPID DEEPENING PHASE OF THE STORM...THE
FIRST HALF OF TUE...STRONG ELY LOW LEVEL JET WILL DEVELOP. GEFS
STANDARDIZED ANOMALIES ACTUALLY REACH -6 STANDARD DEVIATIONS FOR
THE U WIND. THIS TYPE OF MAGNITUDE FOR THE LOW LEVEL JET WILL
USUALLY FOCUS SIGNIFICANT ENHANCEMENT ALONG THE ERN SLOPES...WITH
DOWNSLOPE PRECIP SHADOWING TO THE NW OF THE HIGH TERRAIN. SO SOME
QPF MAY BE LOST TO THIS FOR PARTS OF GRAFTON AND COOS
COUNTIES...BUT ENOUGH OF THOSE ZONES SEE HIGH ENOUGH QPF TO
WARRANT A WINTER STORM WATCH FOR ALL ZONES IN THE FORECAST AREA.

LOW PRES WILL BE OCCLUDING AT SOME POINT DURING THIS PERIOD...SO
DETAILS ARE HARD TO PIN DOWN WITHOUT HAVING A BETTER IDEA OF
EXACTLY WHEN AND WHERE THIS OCCURS. BUT IN GENERAL...A HEAVY BAND
OF SN WILL LIFT N THRU THE AREA WITH THE INITIAL BURST OF INTENSE
WAA ALOFT. THIS WILL BE TUE MORNING...IMPACTING THE COMMUTE...AND
SNWFL MAY REACH 1 INCH PER HOURS AT TIMES. ONCE WAA LIFTS N OF THE
AREA THE QUESTIONS BECOMES WHETHER ANY DEFORMATION CAN LINGER OVER
THE AREA AND IF WE CAN MAINTAIN SATURATION ALOFT TO CONTINUE
ACCUMULATING SNWFL. MODEL HEIGHT FIELDS SUGGEST A BACK BENT WARM
FNT ALOFT...AND STRONG DYNAMICS ASSOCIATED WITH FEATURES LIKE THIS
CAN THROW A WRENCH IF YOU TRY AND GET TOO SPECIFIC AT THIS TIME
RANGE. TUE NIGHT INTO WED UPPER LOW WILL DRIFT THRU THE GULF OF
ME...AND LIGHT SNWFL WILL CONTINUE THRU THIS TIME PERIOD.

THE LAST MAJOR CONCERN IS THE WIND FORECAST. STRONG..BUT
WEAKENING...LOW LEVEL JET WILL BE LIFTING N ACROSS THE AREA TUE.
GFS FORECAST IS MOST AGGRESSIVE WITH MIXING...BUT DEEP COLD AIR IN
PLACE AHEAD OF THE STORM SUGGESTS THAT SIGNIFICANT MIXING IS
POSSIBLE. IF MIXING TO ABOUT H9 IS ASSUMED...A PERIOD OF 40 TO 45
KT GUSTS IS POSSIBLE ALONG THE COAST TUE. HOWEVER CONFIDENCE WAS
TOO LOW TO GO WITH ANY BLIZZARD HEADLINES AT THIS TIME. THAT BEING
SAID...POTENTIAL IS THERE FOR AT LEAST NEAR-BLIZZARD OR WHITEOUT
CONDITIONS DURING THE DAY TUE. THERE IS AT LEAST ONE MORE MODEL
CYCLE TO ANALYZE TO ASSESS ANY TRENDS IN THIS WIND FORECAST FOR
ANY POSSIBLE UPGRADES TO THE WATCH HEADLINES.

PUTTING ALL THIS INFORMATION TOGETHER YIELDS A WIDESPREAD DOUBLE
DIGIT SNWFL FOR THE AREA. BASED ON HEIGHT FIELDS...WINDS
ALOFT...AND EXPECTED QPF ENHANCEMENT...HIGHEST AMOUNTS LOOK LIKELY
ACROSS SRN NH AND ESPECIALLY THE MONADNOCKS.

BEYOND THIS STORM SYSTEM A MUTLI-MODEL CONSENSUS WAS USED THRU THE
REST OF THE EXTENDED. THERE WAS A FAIR AMOUNT OF
AGREEMENT...THOUGH ENOUGH TIMING DIFFERENCE EXIST TO MAKE NAILING
DOWN EXACT WINDOWS FOR THE NEXT STORM SYSTEMS DIFFICULT. HOWEVER BOTH
THE ECMWF AND GFS APPEAR FAVORABLE FOR SNWFL LOVERS THRU THE END
OF JAN...OFFERING ADDITIONAL CHANCES TO BOOKEND THE WEEKEND.

&&

.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...VFR TODAY WITH SFC WIND GUSTS AROUND 25 KT. VFR
TONIGHT AND MONDAY WITH LIGHTER WINDS AS HIGH PRESSURE MOVES INTO
THE AREA.

LONG TERM...HIGH CONFIDENCE IN A PERIOD OF IFR AND LOWER
CONDITIONS BEGINNING MON NIGHT THRU TUE...AS COASTAL LOW PRES
SPREADS SNWFL ACROSS THE AREA. HEAVY SNWFL AND WIDESPREAD IFR OR
LOWER CONDITIONS WIND DOWN TUE EVENING...BUT SN LINGERS INTO WED
MORNING WITH SCT IFR CONDITIONS POSSIBLE. COASTAL TERMINALS MAY
SEE NE GUSTS NEAR 30 KTS DURING THE DAY TUE.

&&

.MARINE...
SHORT TERM...SCA FOR THE BAYS AND GALE THE OCEAN WATERS FOR TODAY
AS CAA IN THE WAKE OF A COLD FRONT SHOULD BE STRONG. WINDS AND
SEAS DIMINISH TONIGHT AND MONDAY AS HIGH PRESSURE BUILDS OVER THE
WATERS.

LONG TERM...STRONG LOW PRES S OF NEW ENGLAND WILL LIKELY BRING A
PERIOD OF STORM FORCE WIND GUSTS TO THE OUTER WATERS TUE INTO TUE
NIGHT. GALES LIKELY FOR THE BAYS DURING THIS TIME...WITH A LOW
PROB OF STORM FORCE GUSTS THERE AS WELL.

&&

.COASTAL FLOODING...
HIGHEST TIDES EARLY TUE MORNING WILL LIKELY OCCUR PRIOR TO
STRONGEST WINDS AND WAVE ACTION. HOWEVER DEPENDING ON STRENGTH AND
DURATION OF NE FLOW...MINOR OR NEAR-MINOR FLOODING IS POSSIBLE.
GIVEN THE HIGH SEAS EXPECTED...SPLASH OVER AND EROSION LOOKS
LIKELY...ESPECIALLY S OF PORTLAND.

&&


.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WINTER STORM WATCH FROM MONDAY EVENING THROUGH LATE TUESDAY
     NIGHT FOR MEZ007>009-012>014-018>028.
NH...WINTER STORM WATCH FROM MONDAY EVENING THROUGH LATE TUESDAY
     NIGHT FOR NHZ001>015.
MARINE...GALE WATCH FROM LATE MONDAY NIGHT THROUGH TUESDAY EVENING FOR
     ANZ151-153.
     SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR ANZ151-
     153.
     STORM WATCH FROM LATE MONDAY NIGHT THROUGH TUESDAY EVENING FOR
     ANZ150-152-154.
     GALE WARNING UNTIL 7 PM EST THIS EVENING FOR ANZ150-152-154.

&&

$$

NEAR TERM...EKSTER
SHORT TERM...EKSTER
LONG TERM...LEGRO