FXUS61 KALY 281141
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
641 AM EST SAT NOV 28 2009
.SYNOPSIS...
A VERY STRONG LOW PRESSURE SYSTEM OVER DOWNEAST MAINE EARLY THIS
MORNING WILL MOVE NORTHEAST THROUGH THE CANADIAN MARITIMES TODAY.
AS IT MOVES AWAY FROM OUR REGION...THE TIGHT PRESSURE GRADIENT
OVER US WHICH HAS BEEN RESPONSIBLE FOR THE STRONG GUSTY WINDS WILL
START TO WEAKEN...AND THE PRECIPITATION WHICH HAS INCLUDED A
MIXTURE OF MAINLY RAIN IN THE VALLEYS AND MAINLY SNOW ACROSS THE
HIGHER ELEVATIONS WILL PULL NORTHEAST AWAY FROM OUR REGION. HIGH
PRESSURE WILL BUILD INTO THE AREA FROM THE SOUTHWEST LATER TONIGHT
INTO EARLY SUNDAY...BEFORE ANOTHER STORM SYSTEM APPROACHES OUR
REGION FROM THE GREAT LAKES SUNDAY EVENING BRINGING MORE UNSETTLED
WEATHER SUNDAY NIGHT INTO MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE STRONGEST WINDS HAVE OCCURRED IN MOST PLACES SINCE 06Z AND
EXPECT THAT THERE STILL MAY BE A FEW HIGHER GUSTS AS WINDS MAX OUT
ACROSS BULK OF FA BTWN NOW AND 15Z THIS MORNING BASED ON PRESSURE
GRADIENT...0-30 MB AGL WINDS WHICH STILL HAVE NUMEROUS FLAGS
ORIENTED FROM SRN VT AND BERKS BACK WEST INTO THE ERN CATSKILLS AT
12Z...AND ISALLOBARIC COUPLET AT 12Z OF +5 TO -10 ON THE GFS AND
+6 TO -8 ON THE NAM. THE LOW BECOMES VERTICALLY STACKED AS IT
DRIFTS INTO THE CANADIAN MARITIMES LATER THIS MORNING INTO EARLY
THIS AFTERNOON AND THE PRESSURE GRADIENT SHOULD START TO WEAKEN
AFTER 18Z. THUS WIND ADVISORY AND HIGH WIND WARNING WILL BE LEFT
IN TACT WITH NO CHANGE TO WIND FIELDS FOR THE NEAR TERM. FOR
INFORMATION ON WIND GUSTS REFER TO ALBPNSALY AND FOR WIND DAMAGE
REPORTS REFER TO ALBLSRALY. AS FOR PCPN SHIELD IT HAS STARTED TO
SHRINK IN COVERAGE AND WEAKEN IN INTENSITY THE LAST COUPLE OF
HOURS AND LITTLE ADDITIONAL ACCUMULATION IS EXPECTED AT THIS
POINT. HOWEVER...THE HIGHER ELEVATIONS OF THE BERKSHIRES AND
SOUTHERN GREEN MOUNTAINS PICKED UP SEVERAL INCHES OF SNOW FROM
FRIDAY EVENING THROUGH THE OVERNIGHT PERIOD WHILE ELEVATIONS BELOW
1000 FEET REMAINED ALL RAIN. PLEASE REFER TO ALBPNSALY FOR THE
LATEST SNOWFALL ACCUMULATIONS. FOR THIS AFTERNOON EXPECT SOME
SUBSIDENCE/DOWN SLOPING WHICH WILL ACTUALLY RESULT IN SOME BREAKS
OF SUN AND ANY LINGERING PCPN WHICH MAY HAVE SOME LAKE ENHANCEMENT
WOULD BE CONFINED TO FAR WESTERN PORTION OF FA. HIGHS WILL BE IN
THE UPPER 30S TO UPPER 40S IN MOST AREAS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
FOR TONIGHT...ANY LINGERING SNOW SHOWERS EXPECTED TO BE CONFINED
TO THE WESTERN THIRD OF FA THIS EVENING WITH THE SNOW ENDING LAST
ACROSS THE WESTERN ADIRONDACKS WHERE A LITTLE LAKE ENHANCEMENT IS
POSSIBLE. FOR NOW WILL JUST GO WITH CHANCE POPS. LOWS TONIGHT
EXPECTED TO BE IN THE MID 20S TO LOWER 30S.
SUNDAY...LOOKS DRY AS HIGH PRESSURE BUILDS INTO FA WITH HIGHS IN
THE UPPER 30S TO LOWER 50S AND MUCH LESS WIND. CLOUDS WILL
INCREASE AGAIN ESPECIALLY DURING THE AFTERNOON AHEAD OF THE NEXT
SHORT WAVE.
ON SUNDAY NIGHT AND MONDAY...CLIPPER SYSTEM MOVING THROUGH THE
EASTERN GREAT LAKES SUNDAY EVENING WILL TRACK NORTHEAST UP THE
SAINT LAWRENCE RIVER VALLEY LATE SUNDAY NIGHT INTO MONDAY WHICH
WILL ONCE AGAIN BRING MIXED PCPN TO OUR REGION ALTHOUGH ANY LIGHT
SNOW SHOULD BE CONFINED MAINLY TO THE WESTERN ADIRONDACKS WHERE
AROUND AN INCH OF ACCUMULATION IS POSSIBLE BEFORE CHANGING OVER
TO MAINLY RAIN FOR A SHORT TIME ON MONDAY BEFORE COLDER AIR FUNNELS
BACK INTO THE REGION. MOST OTHER AREAS WILL HAVE RAIN WITH MAINLY
LIGHT QPF AMOUNTS IN THE QUARTER TO THIRD OF AN INCH RANGE.
EXPECT LOWS SUNDAY NIGHT IN THE UPPER 20S TO UPPER 30S WITH HIGHS
ON MONDAY IN THE UPPER 30S TO UPPER 40S.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
HIGH PRESSURE GRADUALLY BUILDS IN FROM THE TN VALLEY MONDAY NIGHT.
THE WEST TO NORTHWEST FLOW...ALONG WITH RAPIDLY COOLING BOUNDARY
LAYER TEMPERATURES...SHOULD PROMOTE SOME LAKE EFFECT MOISTURE AND
CLOUDINESS. SOME LAKE EFFECT SNOW SHOWER ACTIVITY IS POSSIBLE IN THE
ADIRONDACKS. LAKE EFFECT MOISTURE AND CLOUDS WILL PERIODICALLY
SPREAD ACROSS MUCH OF THE REGION THROUGH WEDNESDAY...ALONG WITH
ISOLATED/SCATTERED SNOW SHOWERS IN THE ADIRONDACKS. SOME FLAT UPPER
RIDGING BUILDS INTO THE REGION TUESDAY AND WEDNESDAY...SO BOUNDARY
LAYER TEMPERATURES WILL WARM GRADUALLY THROUGH WEDNESDAY.
LOWS MONDAY NIGHT IN THE 20S...SOME TEENS IN THE ADIRONDACKS. HIGHS
TUESDAY IN THE 40S...BUT 30S IN THE ADIRONDACKS...CATSKILLS AND
SOUTHERN GREEN MOUNTAINS. LOWS TUESDAY NIGHT WILL BE IN THE 20S TO
AROUND 30. HIGHS WEDNESDAY SHOULD BE IN THE MID TO UPPER 40S...SOME
UPPER 30S IN THE ADIRONDACKS AND AROUND 40 CATSKILLS AND SOUTHERN
GREEN MOUNTAINS.
THE NEXT SYSTEM APPROACHES FROM THE CENTRAL U.S. WEDNESDAY
NIGHT...WITH SOME HINTS AT A SOUTHERN STREAM PIECE OF UPPER ENERGY
TRACKING OUT OF THE NORTHERN GULF COAST STATES. THERE IS
CONSIDERABLE SPREAD IN LONG RANGE DETERMINISTIC GUIDANCE AND THE
ENSEMBLES AS TO THE TRACK OF THE UPPER AND SURFACE FEATURES...AND
POSITION OF THE ASSOCIATED BOUNDARY LAYER THERMAL GRADIENT. BASED
ON THE LONGWAVE PATTERN ACROSS NORTH AMERICA...EVEN IF THE SYSTEM
TRACKS ALONG THE COAST...BOUNDARY LAYER TEMPERATURES WITHIN THE
FRONTOGENETIC THERMAL GRADIENT NORTHWEST OF THE STORM MAY BE JUST A
LITTLE TOO WARM FOR SNOW IN MANY AREAS. AGAIN...LOTS OF UNCERTAINTY
IN TRACK OF SURFACE AND UPPER FEATURES...AND THERMAL PROFILES AND
RESULTANT PRECIPITATION TYPES.
SO DEPENDING ON ELEVATION AND SURFACE TEMPERATURES...SOME MIX LIKELY
IN HIGHER ELEVATIONS WEDNESDAY NIGHT AND THURSDAY MORNING...WITH
JUST SOME CHANCES FOR MIXING IN VALLEYS. TRANSITION TO RAIN DURING
THE DAY THURSDAY...ENDING AS SNOW SHOWERS MANY AREAS THURSDAY NIGHT.
LOWS WEDNESDAY NIGHT IN THE MID 20S TO AROUND 30 IN HIGHER
ELEVATIONS...LOWER TO MID 30S VALLEYS. HIGHS THURSDAY IN THE LOWER
TO MID 40S...LOWER TO MID 30S IN THE MOUNTAINS.
MEAN NORTHERN STREAM UPPER TROUGH AXIS NUDGES EVER SO SLIGHTLY
EAST...ALLOWING A LITTLE MORE COLD AIR TO GET INTO EASTERN NORTH
AMERICA TOWARD THE END OF THE WEEK. HIGH PRESSURE AGAIN BUILDS IN
FROM THE TN VALLEY THURSDAY NIGHT AND FRIDAY. WITH COOLING OF
BOUNDARY LAYER TEMPERATURES AND WEST TO NORTHWEST WINDS...LAKE
EFFECT CLOUDS AND ISOLATED/SCATTERED SNOW SHOWER ACTIVITY STARTS UP
AGAIN. LOWS THURSDAY NIGHT IN THE 20S...TEENS IN THE MOUNTAINS.
HIGHS FRIDAY IN THE 30S TO AROUND 40.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
LOW PRESSURE CONTINUES TO TRACK OFF NEW ENGLAND...AND THE STRONG
WINDS ASSOCIATED WITH IT WILL CONTINUE THROUGH MUCH OF TODAY.
A FEW SHOWERS AND SPRINKLES ARE STREAMING THROUGH THE MOHAWK
VALLEY...SO VCSH PERHAPS THROUGH 14Z.
DUE TO SOME DOWNSLOPE FLOW...ALL AREAS WILL SEE CEILINGS ABOVE
3000 FEET. THE CLOUDS WILL BECOME SCATTERED LATER THIS
AFTERNOON...BUT A BROKEN TO OVERCAST CEILING BETWEEN 3500-6000
FEET SHOULD REDEVELOP TOWARD EVENING... ESPECIALLY AT KGFL AND
KALB AS LAKE EFFECT MOISTURE BEGINS TO STREAM INTO THE REGION.
STRONG NORTHWEST WINDS WILL BE 15 TO 25 KT THROUGH THE DAY...WITH
GUSTS 30 TO 40 KT DURING THE DAY. WINDS WILL DIMINISH AFTER
SUNSET...BUT STILL BE A LITTLE GUSTY...AROUND 20 KT AT ALB THROUGH
THIS EVENING.
OUTLOOK...
SUN...VFR. NO SIG WX.
SUN NT-MON...MVFR/IFR. -RA/-SN.
TUE...VFR. SLGT CHC -SHRA/-SHSN.
WED...VFR. NO SIG WX.
&&
.HYDROLOGY...
LIQUID EQUIVALENT PCPN AMOUNTS WITH THIS SYSTEM HAVE BEEN VERY
LIGHT WITH LESS THAN A TENTH OF AN INCH IN MANY AREAS EXCEPT
ACROSS THE TACONICS AND WESTERN NEW ENGLAND WHERE A HALF INCH TO
AROUND AN INCH FELL. RIVER RISES IN THESE AREAS ARE FORECAST TO
BE AROUND A FOOT. ELSEWHERE..RISES ARE FORECAST TO BE LESS THAN
HALF A FOOT. LITTLE ADDITIONAL QPF IS EXPECTED TODAY WITH MAINLY
DRY WEATHER TONIGHT AND SUNDAY BEFORE NEXT SYSTEM ARRIVES SUNDAY
NIGHT INTO MONDAY WITH GENERALLY A QUARTER TO A THIRD OF AN INCH
OF QPF.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...WIND ADVISORY UNTIL 6 PM EST THIS EVENING FOR CTZ001-013.
NY...HIGH WIND WARNING UNTIL 6 PM EST THIS EVENING FOR NYZ033-042-
047-051-058-063-082.
WIND ADVISORY UNTIL 6 PM EST THIS EVENING FOR NYZ032-038>041-
043-048>050-052>054-059>061-064>066-083-084.
MA...HIGH WIND WARNING UNTIL 6 PM EST THIS EVENING FOR MAZ001-025.
VT...HIGH WIND WARNING UNTIL 6 PM EST THIS EVENING FOR VTZ013-014.
WIND ADVISORY UNTIL 6 PM EST THIS EVENING FOR VTZ015.
&&
$$
AVIATION...NAS
