FXUS61 KGYX 300241
AFDGYX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
941 PM EST SUN NOV 29 2009
.SYNOPSIS...
LOW PRESSURE OVER LAKE ONTARIO WILL TRACK DOWN THE SAINT LAWRENCE
VALLEY AND DRAG A TRAILING COLD FRONT ACROSS THE REGION MONDAY. A
RIDGE OF HIGH PRESSURE WILL BUILD TO THE SOUTH OF THE AREA TUESDAY
AND WEDNESDAY. A STRONG LOW PRESSURE SYSTEM LOCATED OVER THE MID
ATLANTIC STATES WEDNESDAY NIGHT WILL MOVE NORTH ON THURSDAY AND
MOVE UP THE ST LAWRENCE RIVER VALLEY THURSDAY AFTERNOON. THE
REMNANTS OF THAT STORM WILL THEN LIFT INTO THE CANADIAN MARITIMES
THROUGH FRIDAY NIGHT.
&&
.NEAR TERM /UNTIL 8 AM MONDAY MORNING/...
RADAR INDICATED AN AREA OF OVERRUNNING PRECIPITATION OVER LAKE
ONTARIO AND NORTHEASTERN NEW YORK STATE. TRAJECTORIES AS WELL AS
LATEST NUMERICALS SUGGEST THE BULK OF THIS ACTIVITY REMAINS NORTH
OF A /KLEB/ LEBANON TO /KWVL/ WATERVILLE LINE OVERNIGHT. THE
EVENING RAOBS WERE DRY AND COLD AND THE COLUMN SHOULD COOL FOR A
PERIOD OF SNOW FOLLOWING PRECIPITATION ONSET...WITH SPOTTY SLEET
AND FREEZING RAIN POSSIBLE TOWARDS DAWN AS WARMER AIR BEGINS TO
ARRIVE. ELSEWHERE...ONLY SPOTTY LIGHT RAIN IS EXPECTED WITH
BOUNDARY LAYER TEMPERATURES EXPECTED TO REMAIN AT LEAST SEVERAL
DEGREES ABOVE FREEZING AFTER THE PRECIPITATION BEGINS. ADJUSTED
THE 1ST PERIOD TEMPERATURE CURVE TO REFLECT MINIMUM TEMPERATURES
OCCURRING OVER THE NEXT 2 OR 3 HOURS BEFORE THICKER CLOUD COVER AND
DEVELOPING SOUTHERLY FLOW SHOULD ALLOW SOME RECOVERY IN READINGS.
PREV DISC...
NEXT SYSTEM CRANKING ACROSS THE GREAT LAKES ATTM. A 500MB SHORT
WAVE IN FAST 500 MB FLOW...IT GAINS A LITTLE ENERGY AND SHOWS A
SLIGHT NEG TILT OVERNIGHT AS A DEVELOPING SFC LOW TRACK
FROM NEAR TORONTO THIS EVE...AND HEAD ENE...SKIMMING THE
INTERNATIONAL BORDER. WILL SEE SOME WAA PRECIP BREAK OUT ACROSS
THE NRN ZONES...MAINLY AFTER MIDNIGHT. P-TYPE FORECAST IS THE
CHALLENGE OVERNIGHT. PRECIP LIKELY TO BEGIN AS SNOW...BUT WILL
BEGIN TO CHANGEOVER TO LIQUID PRECIP...ESPECIALLY IN NRN NH TOWARD
DAYBREAK. SOME COLDER VALLEYS COULD SEE A SHORT PERIOD OF FZRA
BEFORE SFC TEMPS WARM ABOVE FREEZING AFTER SUNRISE....WITH AN OR
TWO OF SNOW POSSIBLE BEFORE THE CHANGEOVER. IN THE NE CORNER OF
ME...THIS TRANSITION WILL PROB NOT TAKE PLACE UNTIL AROUND OR AFTER
SUNRISE. IN THE FOOTHILLS...AND AREAS JUST S AND E...LOOK FOR
MAINLY SHRA DEVELOPING AFTER MIDNIGHT....WHILE ALONG THE COAST
IT/LL BE MAINLY DRY...BUT CAN'T RULE OF SHRA TOWARD DAYBREAK.
&&
.SHORT TERM /8 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
COLD FRONT TRAILING SFC LOW TRACKING ACROSS FAR NRN ME...WILL
ENTER THE CT VLY DURING THE MORNING. AGAIN...DURING THE EARLY
MORNING...COULD SEE SOME P[OCKETS OF FZRA IN NW ME...BUT ALL IN
ALL WILL SEE SN TRANSITIONING TO RAIN MORNING HERE...WITH ACCUMS
ON THE ORDER OF 1 TO 3 INCHES. FROM THE FOOTHILLS COAST...LOOK FOR
MAINLY SHRA DURING THE DAY...ALTHOUGH COASTAL AREAS COULD REMAIN
DRY THRU THE MORNING...AND HAVE TO WAIT FOR ANY FORCING RIGHT
ALONG THE FRONT BEFORE ANY PRECIP BEGINS. PRECIP WILL START TO END
FROM W TO E DURING THE MID-LATE AFTERNOON...BUT WILL COULD LINGER
INTO THE EVE IN FAR ERN ZONES.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
WEAK RIDGING SHOULD PROVIDE A PRECIPITATION FREE MONDAY NIGHT...
THOUGH ENOUGH RESIDUAL MOISTURE TO PROVIDE SOME DEGREE OF CLOUD
COVER THROUGH LATER TUESDAY. ANOTHER WEAK RIDGE CROSSES THE
REGION WEDNESDAY MORNING WHICH SHOULD PROVIDE SOME DEGREE OF
SUNSHINE. CLOUDS INCREASE LATER WEDNESDAY IN ADVANCE OF ANOTHER
APPROACHING STORM SYSTEM. MODEL SOLUTIONS HAVE REVERSED THEMSELVES
SINCE YESTERDAY WITH BOTH THE 06Z/12Z RUNS BRINGING THIS SYSTEM
TO OUR WEST AND MOVING IT UP THE ST LAWRENCE VALLEY ON THURSDAY.
THIS WOULD PROVE TO BE MOSTLY A RAIN MAKER FOR MOST OF THE FORECAST
AREA WITH THE EXCEPTION OF NORTHERNMOST/MOUNTAIN SECTIONS. ENSEMBLE
FORECASTS ALSO LEANING THIS WAY SO LEANING MORE TOWARDS THIS
SCENARIO...THOUGH STILL AMPLE TIME FOR ADJUSTMENTS TO TRACK. THIS
SYSTEM LIFTS INTO THE CANADIAN MARITIMES WITH WHAT LOOKS TO BE
ANOTHER SPOKE COMING AROUND IT FOR LATER FRIDAY. INITIAL SOLUTIONS
SHOW THAT TO BE MINOR AND IT MAY JUST ALSO LIFT ITSELF INTO THE
CANADIAN MARITIMES FRIDAY NIGHT. HIGH PRESSURE THEN APPROACHES AND
SHOULD PROVIDE A MOSTLY DRY SATURDAY/SATURDAY NIGHT. A DEVELOPING
SOUTHWESTERLY FLOW ON THE BACKSIDE OF THE HIGH WILL INCREASE CLOUDS
WITH A CHANCE OF PRECIPITATION. TEMPERATURES THROUGH THE PERIOD MOSTLY
AT OR ABOVE SEASONABLE NORMALS.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
SHORT TERM...EXPECTING MAINLY VFR AT THE TERMINALS THRU
MONDAY...HOWEVER A SHORT PERIOD OF MVFR CIGS/VIS POSSIBLE IN SHRA
LATE MORNING INTO AFTERNOON. KLEB WILL BE THE EXCEPTION...AS IT
WILL SEE SOME FOG AND LOW STRATUS DEVELOP AFTER MIDNIGHT...BUT IT
MAY ALSO BE VARIABLE AS SHRA MOVE THRU AND MIX THINGS OUT AT A BIT
AT TIMES.
LONG TERM...MOSTLY VFR MONDAY NIGHT THROUGH WEDNESDAY EXCEPT FOR
LOCAL MVFR IN ANY SNOW SHOWER ACTIVITY TUESDAY NIGHT OVER NORTHERN/
MOUNTAIN SECTIONS. CONDITIONS LOWERING TO IFR/LIFR WEDNESDAY NIGHT
THROUGH THURSDAY IN RAIN OVER SOUTHERN/COASTAL SECTIONS AND IN
SNOW OVER NORTHERN/MOUNTAIN SECTIONS...IMPROVING TO MVFR THURSDAY
NIGHT. MOSTLY VFR FRIDAY.
&&
.MARINE...
SHORT TERM...THE WATERS REMAIN BLO SCA THROUGH MONDAY...BUT WILL
LKLY SEE A SURGE IN SW FLOW MON MORNING...WHICH WILL BRING BOTH
WINDS AND SEAS CLOSE TO SCA LVLS.
LONG TERM...SCA CRITERIA POSSIBLE MONDAY NIGHT THROUGH WEDNESDAY.
GLW CRITERIA POSSIBLE WEDNESDAY NIGHT INTO THURSDAY...THEN SCA
CONDITIONS POSSIBLE THURSDAY NIGHT INTO FRIDAY.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
