National Weather Service Raw Text Product

421 
FXUS61 KALY 100541
AFDALY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
1240 AM EST MON JAN 10 2011

.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO ONTARIO AND THE GREAT LAKES REGION
THROUGH TUESDAY...BEFORE ANOTHER POSSIBLE COASTAL STORM IMPACTS THE
REGION WITH SNOW TUESDAY NIGHT AND WEDNESDAY.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
AS OF 950 PM EST...CLOUDS AND SNOW SHOWERS/FLURRIES PERSIST ACROSS
THE DACKS...AND HIGHER ELEVATIONS ACROSS THE SCHOHARIE
VALLEY/EASTERN CATSKILLS...AND ACROSS HIGHER ELEVATIONS OF
SOUTHERN VT/WESTERN MA. IN VALLEYS...CLOUDS HAVE INCREASED FROM
ALBANY NORTH...WITH CLEAR TO PARTLY CLOUDY SKIES FURTHER S.

A RATHER POTENT SHORTWAVE WAS NOTED ON WV SATELLITE IMAGERY...OVER
EAST CENTRAL QUEBEC AND HEADING S. THIS FEATURE SHOULD PASS FROM N
TO S ACROSS THE REGION TOWARD...OR AROUND DAYBREAK. AS IT
APPROACHES...SOME INCREASING SYNOPTIC LIFT...IN COMBINATION WITH
SOME LAKE MOISTURE...AND RESIDUAL MID LEVEL MOISTURE FROM THE
ATLANTIC SHOULD COMBINE TO INCREASE THE AREAL COVERAGE OF SNOW
SHOWERS AND FLURRIES ACROSS CENTRAL AND NORTHERN PORTIONS OF THE
REGION. IN FACT...SOME ADDITIONAL LIGHT ACCUMS ARE EXPECTED ACROSS
THE WESTERN DACKS...ABOUT 1-3 INCHES...AND ALSO HIGHER WEST FACING
TERRAIN IN SOUTHERN VT...WHERE 1-2 INCHES WILL BE POSSIBLE...ALONG
WITH ISOLATED HIGHER AMOUNTS...AND PERHAPS UP TO AN INCH ACROSS
THE SCHOHARIE VALLEY...WESTERN MOHAWK VALLEY...AND BERKSHIRES.
ACROSS VALLEY AREAS...SOME FLURRIES SHOULD REDEVELOP FROM ALBANY
NORTH.

SO...HAVE BOOSTED POPS SLIGHTLY IN AFOREMENTIONED HIGHER
ELEVATIONS...ESP ACROSS THE WESTERN DACKS. AND...WITHIN VALLEYS
FROM THE CAPITAL REGION NORTH...HAVE ADDED MENTION OF SCATTERED
FLURRIES...WITH PERHAPS A FEW DUSTINGS OCCURRING THROUGH DAYBREAK.

AS FOR TEMPS...HAVE KEPT MINS THE SAME...BUT SLOWED DOWN THE
OVERALL TEMP CURVE OVERNIGHT...AS CLOUDS AND WIND SHOULD KEEP
TEMPERATURES FROM FALLING MUCH THROUGH MIDNIGHT...BEFORE FALLING
MORE RAPIDLY RIGHT AROUND DAYBREAK WHEN SOME BREAKS IN THE CLOUDS
MAY DEVELOP AS SUBSIDENCE DEVELOPS WITH THE PASSAGE OF THE
AFOREMENTIONED SHORTWAVE.

OTHERWISE...JUST SOME MINOR TWEAKS TO HOURLY TEMPS/DEWPOINTS/WINDS
ACCORDING TO RECENT OBS.

PREVIOUS DISCUSSION FOLLOWS...

ANOTHER TRICKY FORECAST TONIGHT...LIKE LAST NIGHT...AS AREAS THAT
SEE PERIODS OF CLEARING SHOULD SEE COLDER LOWS THAN AREAS THAT SEE
MORE CLOUDS. GRANTED...BOUNDARY LAYER FLOW IS STRONG...AND WILL
MIX TO SOME DEGREE TO THE SURFACE...BUT SOME VALLEY AREAS...SUCH
AS AROUND GFL AND POU...CAN SEE VERY LIGHT WINDS WHEN BOUNDARY
LAYER FLOW IS WEST OR NORTHWEST.

SOME MOISTURE BACKING SOUTH AND WEST OUT OF NORTHERN NY...COULD
RESULT IN A COUPLE OF INCHES OF SNOW IN PARTS OF THE SOUTHERN
ADIRONDACKS. THE NORTHWEST FLOW SHOULD AIM LAKE EFFECT MOISTURE
MAINLY INTO THE WESTERN MOHAWK VALLEY AND SCHOHARIE VALLEY AS
LITTLE MULTIBANDS...SO LOCALIZED INCH OR TWO POSSIBLE THERE
OVERNIGHT. 

LOWS GENERALLY IN THE TEENS...WITH SOME SINGLE NUMBERS IN THE
ADIRONDACKS...AND NORTHERN LAKE GEORGE SARATOGA REGION.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/...
LINGERING NORTHWEST FLOW AND LAKE EFFECT MULTIBAND SNOW SHOWER
ACTIVITY COULD ADD LIGHT ACCUMULATIONS IN THE WESTERN MOHAWK
VALLEY...SCHOHARIE VALLEY AND SOUTHERN ADIRONDACKS THROUGH MONDAY
MORNING. PERIODS OF CLOUDS AND SUN MOST AREAS MONDAY...WITH BREEZY
CONDITIONS EARLY...AND EASING WINDS THROUGH THE AFTERNOON. HIGHS
MONDAY IN THE 20S TO AROUND 30.

WEAK HIGH PRESSURE BUILDS IN MONDAY NIGHT THROUGH TUESDAY...WITH
LIGHT WINDS...AND GRADUALLY DECREASING CLOUD COVER. LOWS MONDAY
NIGHT...WITH LIGHTER WINDS...MORE CLEARING...AND SNOW
PACK...AROUND 10 TO LOWER TEENS...AROUND 0 SOUTHERN
ADIRONDACKS...LAKE GEORGE AND SARATOGA REGION. HIGHS
TUESDAY...WITH INCREASING HIGH CLOUDS AHEAD OF THE NEXT
SYSTEM...IN THE 20S TO LOWER 30S. SOME LIGHT SNOW COULD WORK ITS
WAY INTO THE NORTHEASTERN CATSKILLS BY LATE TUESDAY AFTERNOON.

THE NEXT SYSTEM...LOOKS TO BE A PHASING OF THE CURRENT GULF COAST
SYSTEM...AND NORTHERN STREAM ENERGY CURRENTLY AROUND THE NORTHERN
ROCKIES. SOURCES OF GUIDANCE AND ENSEMBLES IN UNUSUALLY GOOD
AGREEMENT ON THE PREDICTED LARGE SCALE EVOLUTION OF THE SYSTEM.  

GULF COAST SYSTEM QUITE DYNAMIC NOW...BUT GUIDANCE CONSENSUS
SUGGESTS DEAMPLIFICATION AND WEAKENING AS IT TRACKS TOWARD THE
COASTAL CAROLINAS. HOWEVER...THE ATMOSPHERIC DEEP MOISTURE AND
POTENTIAL VORTICITY FOOTPRINT WILL STILL EXIST...LIKE A FUSE THAT
JUST NEEDS TO BE RE-LIT. THE LOW LEVEL FEATURE IS PREDICTED TO
EMERGE OFF THE CAROLINAS...WITH THE GULF STREAM AND THERMAL
GRADIENT BAROCLINICITY LIGHTING THE FUSE. THE NORTHERN STREAM
UPPER ENERGY AND DYNAMICS COULD SUPPORT SOME ENSUING CONVECTIVE
FIREWORKS AND THE SNOW BOMBS BURSTING IN AIR AS THE STORM DEVELOPS
OFF THE CAROLINAS AND MID ATLANTIC COAST. O.K. THAT MIGHT HAVE
BEEN TOO POETIC...BUT SOME HINTS AT CONVECTIVE CHARACTER TO SYSTEM
WITH SOME DOWNSTREAM UPPER RIDGING...THAT COULD STEER THE SYSTEM
ALONG THE MORE NORTHWESTERN PREDICTED TRACKS IN GUIDANCE.

WIND ANOMALIES AT 850 HPA SUGGEST BETTER THAN AVERAGE MOISTURE
CONVERGENCE AND ADVECION OFF ATLANTIC...BUT CLOSED UPPER LOW DOES
LOOK PROGRESSIVE...NOT AN UPPER CUT OFF...EVIDENT IN 250 HPA WIND
ANOMALIES. HOWEVER...BOUNDARY LAYER FRONTOGENESIS IMPRESSIVE...AND
BEST UPWARD VERTICAL MOTION SHOULD CUT THROUGH THE DENDRITIC -12C
TO -18C GROWTH ZONE IN A RELATIVELY DECENT LAYER OF THE
ATMOSPHERE. MESOSCALE BANDING WILL HAVE TO BE MONITORED...AS IT IS
TOO EARLY TO BE SPECIFIC ON WHERE ENHANCED SNOWFALL RATES OF >2"+
PER HOUR COULD SET UP. BIGGEST SNOWS COULD BE SOUTHERN NY INTO
SOUTHERN AND CENTRAL/EASTERN NEW ENGLAND...OR COULD SHIFT A BIT
WEST TOWARD THE BERKSHIRES...EASTERN NY AND SOUTHERN VT...WE JUST
HAVE TO WAIT AND SEE.

SO...ABOVE AVERAGE CONFIDENCE IN A SNOWSTORM WITH SIGNIFICANT
IMPACTS...BUT FOR NOW...UNTIL THE EVENT GETS CLOSER...THE BIGGEST
IMPACTS LOOK TO BE SOMEWHERE AROUND OR EAST OF THE NY AND NEW
ENGLAND BORDER AND SOUTH OF VT...PERHAPS POU THROUGH LITCHFIELD
COUNTY CT...MAYBE TO PSF...WITH THE UNDERSTANDING SOME ADJUSTMENTS
IN ANY DIRECTION ARE POSSIBLE AS THE EVENT GETS NEARER. AREAS OF
CENTRAL AND EASTERN NEW YORK...INCLUDING THE HUDSON
VALLEY...CAPITAL DISTRICT...THROUGH THE WESTERN MOHAWK
VALLEY...SOUTHERN ADIRONDACKS...SCHOHARIE VALLEY AND NORTHEASTERN
CATSKILLS SHOULD SEE AT LEAST LIGHT TO LOCALLY MODERATE SNOWS AS
THE NORTHERN STREAM UPPER ENERGY TRANSFERS TO THE STRENGTHENING
OFFSHORE SYSTEM. AGAIN...A SLIGHT NORTHWEST SHIFT TO THE TRACK OF
THE SYSTEM...AND HEAVIER SNOWS WOULD BE POSSIBLE IN THE HUDSON
VALLEY AND CAPITAL DISTRICT TO SOUTHERN VT...STAY TUNED.

LOWS TUESDAY NIGHT AROUND 20 TO THE MID 20S...SOME TEENS IN THE
SOUTHERN ADIRONDACKS THROUGH SOUTHERN VT. HIGHS WEDNESDAY IN THE
20S TO LOWER 30S.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
THE PERIOD STARTS OUT WITH THE NOR'EASTER HEADING OUT TO SEA. THERE 
COULD STILL BE SOME LINGERING WRAP-AROUND LIGHT SNOW SHOWERS 
WEDNESDAY NIGHT...ESPECIALLY ACROSS THE FAVORED HIGHER TERRAIN 
LOCATIONS. OTHERWISE...A FLAT RIDGE ALOFT WILL SET UP ACROSS MUCH OF 
THE GREAT LAKES INTO THE NORTHEAST...BUT WITH SOME LAKE EFFECT SNOW 
SHOWERS POSSIBLE ACROSS AREAS WEST OF THE HUDSON VALLEY WITH A N-NW 
FLOW THURSDAY INTO THURSDAY NIGHT. LAKE EFFECT ACTIVITY WILL TEND TO 
DIMINISH ON FRIDAY AS THE FLOW TURNS DECIDEDLY ANTICYCLONIC WITH A 
SURFACE RIDGE OF HIGH PRESSURE BUILDING IN FROM THE OHIO VALLEY. 

TRANQUIL CONDITIONS WITH SEASONABLE TEMPS SHOULD THEN PERSIST 
THROUGH FRIDAY NIGHT AS THE RIDGE MOVES OVERHEAD. HOWEVER...WITH 
FAST ZONAL FLOW ALOFT DEVELOPING...A SURFACE TROF AND ASSOCIATED 
PROGRESSIVE UPPER LEVEL TROF AXIS IS FORECAST TO MOVE THROUGH IN THE 
LATE SATURDAY THROUGH SUNDAY MORNING TIME FRAME. DUE TO TIMING 
DIFFERENCES IN MODEL FORECASTS...WILL MENTION LOW CHANCE POPS ACROSS 
THE ENTIRE AREA. WITH THE TRACK OF THE MAIN CYCLONE PASSING BY WELL 
NORTH OF THE AREA AND A DE-AMPLIFIED UPPER PATTERN...EXPECTING JUST 
SNOW SHOWERS WITH LIGHT ACCUMULATIONS WITH THIS SYSTEM. DRIER AIR 
SHOULD THEN FILTER IN FOR SUNDAY.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
STRONG LOW PRESSURE MOVING INTO THE CANADIAN MARITIMES WILL MAINTAIN 
A BRISK NORTHWEST FLOW ACROSS THE KGFL/KALB/KPOU TAF SITES THROUGH 
MOST OF MONDAY AFTERNOON...THEN WEAK HIGH PRESSURE WILL BUILD INTO 
THE REGION AND WINDS WILL BECOME LIGHT. 

MAINLY A VFR BKN/OVC CU/SC CLOUD DECK WILL BE OVER THE KGFL/KALB TAF 
SITES INTO MONDAY AFTERNOON...WITH FEW/SCT CLOUDS AT KPOU. AT KALB 
THE CLOUD DECK WILL BE HOVERING RIGHT AT THE VFR/MVFR THRESHOLD OF 
3000 FEET THROUGH ABOUT 14Z THIS MORNING...THEN VFR AFTER THAT. BY 
SUNSET AND BEYOND...EXPECT CONDITIONS TO BE MAINLY P6SM SKC. 

WINDS WILL BE WEST TO NORTHWEST AT KALB/KPOU FOR THE REST OF THE 
NIGHT...GENERALLY 10 KTS OR LESS AT KPOU...BUT 10 TO 12 KTS AT KALB 
WITH GUST TO OVER 20 KTS. AT KGFL THE WINDS WILL BE LIGHT AND 
VARIABLE FOR THE REST OF THE NIGHT. BY 14Z THE WEST TO NORTHWEST 
WINDS WILL PICK UP TO 10 TO 15 KTS AT ALL THREE TAF SITES...WITH 
GUSTS OF 15 TO 20 KTS AT KGFL/KPOU...AND AROUND 25 KTS AT KALB. 
AFTER 22Z-23Z...SURFACE WINDS WILL DECREASE TO UNDER 10 KTS AND 
EVENTUALLY BECOME LIGHT AND VARIABLE MONDAY NIGHT.

OUTLOOK...
LATE MON NT-TUE...VFR. NO SIG WX. 
TUE NGT-WED...MVFR/IFR...-SN/SN LIKELY WITH CHC +SN. 
THU-FRI...VFR. NO SIG WX.

&&

.HYDROLOGY...
TEMPERATURES ARE EXPECTED TO REMAIN BELOW FREEZING THROUGH MOST OF 
NEXT WEEK. 

ICE WILL CONTINUE TO THICKEN ON MAIN STEM RIVERS OVER THE NEXT
SEVERAL DAYS ALTHOUGH SNOW COVER ON TOP OF THE ICE MAY SLOW THE
RATE OF INCREASE IN ICE THICKNESS.

OUTSIDE OF SOME UPSLOPE SNOW SHOWERS...THE NEXT CHANCE OF 
PRECIPITATION LOOKS TO BE LATE TUESDAY INTO WEDNESDAY BUT ONCE AGAIN 
THIS PRECIPITATION LOOKS TO BE IN THE FORM OF SNOW.   

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...NONE.
NY...NONE.
MA...NONE.
VT...NONE.

&&

$$
SYNOPSIS...NAS
NEAR TERM...KL/NAS
SHORT TERM...NAS
LONG TERM...JPV
AVIATION...GJM
HYDROLOGY...NAS/JPV