FXUS61 KGYX 220754
AFDGYX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
254 AM EST TUE DEC 22 2009
.SYNOPSIS...
AN UPPER LOW WILL DEVELOP AND MOVE ACROSS CENTRAL NEW ENGLAND
TODAY AND TONIGHT BEFORE MOVING INTO THE GULF OF MAINE WEDNESDAY.
A LARGE RIDGE OF HIGH PRESSURE WILL BUILD OVER NORTHERN NEW
ENGLAND FOR THURSDAY AND CHRISTMAS DAY. A LARGE STORM SYSTEM WILL
MOVE WELL TO THE WEST OF NEW ENGLAND PASSING THROUGH THE GREAT
LAKES SATURDAY...THIS WILL ALLOW A WARM AND WET SOUTHERLY FLOW TO
DEVELOP.
&&
.NEAR TERM /THROUGH TODAY/...
HAVE ISSUED A WINTER STM WRNG FOR A PORTION OF THE WRN MTNS OF
MAINE STARTING LATER TODAY. A STG CLIPPER DROPPING SEWD FROM
CANADA WILL RAPIDLY DEEPEN ALOFT AND CREATE A RATHER IMPRESSIVE
MID/UPPER LOW TO DEVELOP OVR CENTRAL MAINE BEGINNING THIS AFTN.
TAKING A TRACK 2.5 DEGS N OF THE VORT CENTERS AXIS AND ALSO
OVERLAYING TRACK OF H7/H85 MID LOW PUTS SWATH OF STG UVV INTO THE
WRNG AREA OUTLINED FOR LATER TDY. HAVE TAKEN INTO ACCT THE FACT
THAT MSTR WILL BE LIMITED AT ONSET BUT WITH TIME SHOULD TAP SOME
MSTR FROM THE NE. A LARGE AREA OF SNOW THAT WILL DEVELOP N OF THE
AXIS OF THE TRACK WILL SLOWLY DRIFT SW AS LOW MOVES/EVOLVES SEWD.
STAYED CLOSE TO MAV MAX TEMPS. POPS OFF OF GFS WERE USED BUT ADJ
AXIS OF HIEST POPS A LITTLE FURTHER SWD.
&&
.SHORT TERM /TONIGHT/...
UPPER LOW CONTINUES FURTHER DEVELOPMENT AS IT VERY SLOWLY DRIFTS
SEWD TWD THE XTRM SRN MAINE CST BY MRNG. PLENTY OF UVV CONTINUES
THRU THE NIGHT N OF THE AXIS SO HAVE ALSO ISSUED WSWATCHES FOR
ADJACENT ZONES TO THE WRNG AREA IN THE MTNS AND ERN CWA. QPF
GENERATION APPEARS LOW FROM MODELS AND OROGRAPHICS SHOULD HELP AS
WELL AS HIGHER SNW RATIOS. DAY SHIFT MAY HAVE TO MAKE DECISIONS ON
THE WATCHES AS WELL AS IF ANY ADVISORIES FURTHER S MAY ALSO BE
NEEDED. FORECASTER NOTE...THIS SITUATION HAS BEEN KNOWN TO BE HVY
SNOW PRODUCERS IN THE PAST AND OVER A LARGE AREA. A SHARP CUTOFF
WILL OCCUR THOUGH WHERE NOTHING OCCURS JUST ALG/S OF THE AXIS
WHILE N OF AXIS VRY HVY SNWS OCCUR. BLENDED MAV/MET TMPS.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
VERTICALLY STACKED LOW WILL CARVE A PATH RIGHT OVER THE CENTER OF
THE CWA FROM NW TO SE WEDNESDAY...WITH SNOW SHOWERS CONTINUING TO
THE EAST AND NORTH OF THE LOW. BY THIS TIME...THE BULK OF THE SNOW
WILL HAVE FALLEN BUT ANOTHER INCH OR SO IS POSSIBLE OVER PORTIONS
OF SOMERSET AND FRANKLIN COUNTIES AND WILL KEEP THE WINTER STORM
WATCH UP THROUGH 00Z THURSDAY. SOME WRAP-AROUND PRECIP WILL
PERSIST AS THE LOW MOVES OFFSHORE LATE WEDNESDAY NIGHT. SURFACE
HIGH PRESSURE WILL PUSH INTO NEW ENGLAND BY CHRISTMAS DAY AS UPPER
LEVEL RIDGING BUILDS OVER THE AREA. THIS WILL RESULT IN PARTLY
CLOUDY SKIES WITH HIGH TEMPS IN THE MID TO UPPER 30S FOR MOST
LOCATIONS IN NEW HAMPSHIRE AND MAINE BOTH THURSDAY AND FRIDAY.
A LARGE TROUGH WILL DOMINATE THE CONUS OVER THE WEEKEND. THE
TROUGH WILL BECOME NEGATIVELY TILTED AS A STRONG SHORTWAVE MOVES
THRU THE BASE OF THE TROUGH TOWARDS NEW ENGLAND. WARM AIR ADVECTION
SHOWERS WILL BEGIN IN THE SOUTHERN ZONES EARLY SATURDAY AND SPREAD
NORTH AND EAST WITH THE WARM FRONT DURING THE DAY. SNOW IS
EXPECTED INITIALLY OVERNIGHT...BUT A WINTRY MIX OF RAIN/FREEZING
RAIN/SNOW IS POSSIBLE SUNDAY IN THE WARM SECTOR. CHILLIER WEATHER
ARRIVES BEHIND THIS SYSTEM FOR EARLY NEXT WEEK.
&&
.AVIATION /07Z TUESDAY THROUGH SATURDAY/...
SHORT TERM...VFR CONDS TDY BECOMING MVFR TO IFR OVR NRN AND ERN
AREAS LATER TDY SPRDING VERY SLOWLY SWWD TO N OF A KPWM-KLEB LINE
TNGT. ONLY TAF SITE THAT MAY BECOME IFR WILL BE KAUG TNGT AS A
SHARP AXIS DEVELOPS ON WHERE CUTOFF OF SNW WILL OCCUR. KPWM AND
KLEB MAY BE JUST FAR ENOUGH N TO BRIEFLY LOWER TO MVFR CONDS IN A
PERIOD OF SNOW TNGT.
LONG TERM...SIMILAR CONDITIONS CONTINUING INTO WED WITH MOSTLY
VFR/SOME MVFR IN SNOW SHOWERS AT KPWM AND KLEB WITH WORSE
CONDITIONS EXPECTED AT KAUG IN HEAVIER SNOW. ON SATURDAY...SNOW
WILL SPREAD FROM SW TO NE WITH ALL SITES POSSIBLY BEING IMPACTED
BY MVFR CIGS AND VSBYS IN SN SHOWERS.
&&
.MARINE...
SHORT TERM...WILL CONTINUE SCA THRU THE DAY AS NWLY PRES GRAD
WINDS SHOULD REACH MINIMAL SCA CRIT THRU THE DAY. NWLY WINDS WILL
CONTINUE INTO TNGT BUT MAY BE JUST BLO CRIT SO DAY SHIFT CAN
REASSESS SITUATION.
LONG TERM...WINDS WILL BRIEFLY RISE ABOVE SCA CRITERIA LATE
WED/EARLY THU AS A LOW PRESSURE SYSTEM MOVES OFFSHORE.
WINDS AND SEAS WILL INCREASE RAPIDLY ON SAT AS A WARM FRONT
APPROACHES FROM THE SOUTH. A SCA OR EVEN A GALE WARNING MAY BE
NEEDED.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WINTER STORM WATCH FROM THIS EVENING THROUGH WEDNESDAY EVENING
FOR MEZ008-014.
WINTER STORM WARNING FROM 4 PM THIS AFTERNOON TO 7 PM EST
WEDNESDAY FOR MEZ009.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR
ANZ150>154.
&&
$$
MARINE/HANES
