FXUS61 KGYX 110250
AFDGYX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
950 PM EST THU DEC 10 2009
.SYNOPSIS...
***LAKE EFFECT SNOW SHOWERS FROM ONTARIO WILL CONTINUE TO REACH AS
FAR EAST AS MAINE. SEE NEAR TERM DISC BELOW***
STRONG WESTERLY FLOW WILL CONTINUE THROUGH SATURDAY AS LOW
PRESSURE SLOWLY PULLS AWAY TO THE NORTH AND HIGH PRESSURE BUILDS
SOUTH OF NEW ENGLAND. HIGH PRESSURE MOVE OFFSHORE SOUTH OF THE
REGION SATURDAY NIGHT. WEAK LOW PRESSURE WILL APPROACH FROM THE
WEST SUNDAY AND REDEVELOP OFF THE MID ATLANTIC COAST SUNDAY
NIGHT...PASSING OUT TO SEA WELL SOUTH OF THE AREA. WEAK HIGH
PRESSURE WILL BUILD OVER THE REGION ON MONDAY AND WILL DRIFT INTO
THE MARITIMES MONDAY NIGHT. LOW PRESSURE CROSSING CENTRAL QUEBEC
TUESDAY WILL DRAG A COLD FRONT TOWARD THE REGION. A SECONDARY AREA
OF LOW PRESSURE WILL FORM ON THE FRONT SOUTH OF NEW ENGLAND AS IT
CROSSES THE REGION TUESDAY NIGHT. LOW PRESSURE WILL LIFT NORTHEAST
INTO THE MARITIMES ON WEDNESDAY WITH A STRONG NORTHWEST FLOW
DEVELOPING IN ITS WAKE WEDNESDAY NIGHT...LASTING THROUGH THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
IT FEELS LIKE A NIGHT AT THE NWS ALBANY OFFICE...WATCHING LAKE EFFECT
BANDS FROM ONTARIO DANCE ACROSS THE RADAR SCREEN. TONIGHT IS
SURELY A RARE NIGHT (NOT UNHEARD OF...BUT RARE NONETHELESS) AS A
MEGA BAND FROM ONTARIO RIDES STRONG LOW LEVEL WINDS ALL THE WAY
INTO NH/ME. THIS IS BRINGING A BAND OF LAKE EFFECT SNOW SHOWERS
WITH LOCALLY 30+ DBZ VALUES ACROSS NORTHERNMOST
GRAFTON...NORTHERNMOST CARROLL AND SOUTHERN OXFORD COUNTIES.
WAITING FOR SURFACE REPORTS TO CONFIRM THE SNOW SHOWERS. SOME
AREAS MAY BE LOCALLY DOWNSLOPING WHILE OTHERS ARE UPSLOPING AS
WELL.
WILL BE PLACING SNOW ACCUMULATIONS IN THE GRIDS DUE TO THE LAKE EFFECT.
AS 850 MB WINDS SLOWLY VEER SLIGHTLY OVERNIGHT...THERE WOULD BE AN
EXPECTATION THAT THIS BAND WOULD SETTLE SOUTH BY 20 MILES OR SO BY
MORNING. IN ANY CASE...HAVE ATTEMPTED TO SHOW THIS MESOSCALE
FEATURE IN THE GRIDS. HAVE FORECASTED A MAX OF 2-4 INCHES OF SNOW
IN THE AFOREMENTIONED BAND AREAS BY MORNING. IN THE
MOUNTAINS...PSEUDO UPSLOPE CONDITIONS (ALTHOUGH NOT AN OPTIMIZED
WIND DIRECTION) WILL ALLOW FOR 1-3 INCHES UP THERE.
OTHERWISE...NO SIGNIF CHANGES TO THE GRIDS. SOME TOWNS BEGAN TO
DECOUPLE AFTER DARK...BUT BEGAN PICKING UP THE WINDS AGAIN OVER
THE LAST HOUR OR SO. SO...WILL FORECAST 15 TO 25 MPH WINDS WITH A
FEW GUSTS NEAR 35 MPH AS THE STRONG WEST GRADIENT CONTINUES.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
GRADIENT TIGHTENS OVER THE REGION ON FRIDAY PRODUCING ANOTHER
WINDY AND COLD DAY. LOOKING FOR MORE IN THE WAY OF CLOUDS DOWNWIND
OF THE MOUNTAINS AS FLOW TURNS MORE WESTERLY OVER THE EASTERN
GREAT LAKES. WITH COLD AIR CONTINUING TO POUR INTO THE REGION
THURSDAY NIGHT THINK GFS MOS TEMPS LOOKING TOO OPTIMISTIC AND HAVE
GENERALLY GONE WITH LOWER NAM NUMBERS FOR HIGHS ON FRIDAY. LOOKING
FOR SNOW SHOWERS TO CONTINUE IN THE MOUNTAINS WHERE SOME ADDITIONAL
MINOR ACCUMULATIONS WILL BE LIKELY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
THE COLD STRONG W NW FLOW CONTINUES FRIDAY NGT THRU SATURDAY. THE
FLOW LINES UP WELL FROM THE SFC TO H5 TO ALLOW FOR GOOD MIXING
DURING THE DAY. THE UPSLOPE FLOW WILL PRODUCE QUITE A BIT OF
CLOUDINESS AND ISOLD TO SCT -SHSN ACROSS THE MT ZONES WHILE
DOWNSLOPE AREAS SEE LESS CLOUDINESS. A SFC HIGH PRES RIDGE BUILDS
ACROSS THE REGION SATURDAY NGT ALLOWING THE WINDS TO QUICKLY DROP
OFF. THE HIGH MOVES OFFSHORE QUICKLY. A H5 SHORT WAVE TROF MOVES E
TOWARD THE ERN U.S. SUNDAY THEN TO OUR E SUNDAY NGT. A TROF OF LOW
PRES MOVES E WITH IT WHILE A SFC LOW FORMS TO OUR S. THE LOW TRACKS
A BIT TOO FAR S TO HAVE MUCH OF AN IMPACT ON OUR WX...BUT IF IT ENDS
UP TRACKING FURTHER N THEN IT COULD BRING A BETTER CHC OF PRCP AND
MORE QPF. HOWEVER, THE SFC TROF WILL BRING A CHC OF LGT PRCP TO THE
FCST AREA SUNDAY NGT INTO MONDAY...IN THE FORM OF -SN...THOUGH SOME
WARM AIR MAY WORK ITS WAY INTO SRN AND COASTAL AREAS WHICH MIGHT
CAUSE ANY -SN TO CHANGE TO -RN. BEHIND THIS SYSTEM HIGH PRES TRIES
TO NOSE SWD INTO THE REGION MONDAY NGT BUT IS QUICKLY SHUNTED TO THE
NE AS ANOTHER LOW AND TRAILING FNT APPROACH FROM THE W. THIS WILL
LIKELY BRING SOME RAIN OR PSBL MIXED PRCP AS WARMER AIR MOVES IN
AHEAD OF IT AS INDICATED BY H8 TEMPS RISING ABOVE 0 C. MUCH COLDER
AIR MOVES IN BEHIND THIS SYSTEM TUESDAY NGT WITH ANY -SHRA CHANGING
TO -SHSN. COLD BLUSTERY WX CONTINUES WEDNESDAY THRU THURSDAY.
GENERALLY USED GFS40 AND BLEND OF MAV/MET MOS FOR TEMPS AND DEW
POINTS FRIDAY THRU SATURDAY THEN USED GMOS FOR REST OF LONG TERM
FCST WITH SOME MINOR ADJUSTMENTS.
&&
.AVIATION /03Z FRIDAY THROUGH TUESDAY/...
SHORT TERM...GENERALLY VFR THROUGH FRIDAY WITH SOME OCCASIONAL
MVFR CEILINGS/VSBY IN SNOW SHOWERS OVER THE MOUNTAINS AND IN
CENTRAL NH AND ADJACENT WESTERN MAINE WITH THE LAKE EFFECT SNOW
SHOWERS.
LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...COLD STRONG W NW FLOW
FRIDAY NGT THRU SATURDAY WITH VFR CIG AND VSBY AS ANY -SHSN
CONFINED TO THE MT AREAS. TROF OF LOW PRES BRINGS A CHC OF -SN AND
MVFR TO PSBL IFR CONDITIONS SUNDAY NGT INTO EARLY MONDAY. LOW PRES
AND TRAILING FNT BRING A BETTER CHC OF RN TO THE AREA ON TUESDAY
WITH IFR CONDITIONS MORE LIKELY.
&&
.MARINE...
SHORT TERM...CONTINUING GALE WARNING THROUGH FRIDAY ALL WATERS.
JUST HAD ONE GUSTS AS HIGH AS 47 KTS AT IOSN3. UP SEAS FORECAST BY
A COUPLE FEET OVERNIGHT.
LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...WILL EXTEND THE GLW
THRU SATURDAY. THE NAM AND GFS WIND FCST GUIDANCE FOR THE BUOYS
SHOW WINDS AROUND GALE FORCE...OR CLOSE TO IT THRU THIS PERIOD.
TIGHT W NW SFC PRES GRADIENT WHICH LINES UP WELL WITH WINDS
ALOFT...UP TO H5...ALLOWING GOOD MIXING SO IF SUSTAINED WINDS
DON'T REACH GALE FORCE AT TIMES THEN FREQUENT GUSTS WILL. CD AIR
ADVECTION WILL ENHANCE WINDS OVER THE WARMER WATER...AGAIN BETTER
MIXING. WINDS QUICKLY DROP OFF...POSSIBLY BLO SCA LEVELS... FOR
SATURDAY NGT AS A RIDGE OF HIGH PRES BUILDS IN. WINDS BACK AROUND
TO THE SW AND INCREASE /MOST LIKELY TO SCA LEVELS/ ON SUNDAY AS
THE HIGH DEPARTS OUT TO SEA. WINDS AND SEAS LIKELY TO CONT AT SCA
LEVELS FOR A GOOD PART OF MONDAY THRU TUESDAY TIME FRAME.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...GALE WARNING UNTIL 7 PM EST SATURDAY FOR ANZ150>154.
&&
$$
CANNON
