FXUS61 KALY 221726
AFDALY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
1226 PM EST TUE DEC 22 2009

.SYNOPSIS...
HIGH PRESSURE...CENTERED SOUTH OF HUDSON BAY...WILL DOMINATE OUR
WEATHER THROUGH THURSDAY...WITH COLD AND DRY WEATHER. A LOW
PRESSURE SYSTEM WILL MOVE NORTH FROM THE SOUTHERN PLAINS INTO
CENTRAL CANADA LATE IN THE WEEK...WHICH MAY BRING MIXED
PRECIPITATION TO OUR REGION STARTING CHRISTMAS DAY AND LINGERING
INTO THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE GRADIENT BETWEEN THE LOW EAST OF THE MARITIMES AND HIGH
PRESSURE SOUTH AND WEST OF THE REGION WILL CONTINUE TO BRING
NORTHWEST WINDS 10 TO 20 MPH ACROSS THE HIGHER TERRAIN WEST
AND EAST OF THE HUDSON VALLEY...WITH SOME FUNNELING DOWN THE
MOHAWK VALLEY AS WELL. USED THE ADJ/MET GUIDANCE WITH SOME
MINOR ADJUSTMENTS. HAVE GONE WITH MOSTLY CLEAR SKIES TO 
START THE DAY...EXCEPT IN OUR WESTERN ZONES...WITH CLOUDS
INCREASING THIS AFTERNOON WITH A LARGE AREA OF CLOUDS TO
OUR WEST ASSOCIATED WITH A STALLED FRONT OVER THE GREAT
LAKES REGION. HIGH TEMPS TODAY WERE A BLEND OF THE MET/MOS
AND MAV/MOS GUIDANCE...AND WILL RANGE FROM THE UPPER TEENS
IN THE ADIRONDACKS TO THE LOW 30S IN THE HUDSON VALLEY SOUTH
OF ALBANY...ABOUT 10 DEGREES BELOW NORMAL FOR THIS DATE.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
ANOTHER COLD ONE TONIGHT...AGAIN BASED ON A BLEND OF THE MAV/MOS
AND MET/MOS. LOWS TONIGHT ZERO TO 5 ABOVE IN THE ADIRONDACKS TO
THE LOW TEENS IN THE MOHAWK...HUDSON...AND HOUSATONIC VALLEYS. 
WINDS SHOULD SLACKEN SOME AND DECOUPLING MAY TAKE IN SOME OF 
THE SHELTERED AREAS SUCH AS THE HUDSON VALLEY NORTH AND SOUTH OF 
ALBANY. A WEST NORTHWEST VECTOR IS LIKELY TO KEEP THE WINDS 5 TO 10 
MPH DOWN THE MOHAWK VALLEY AND IN THE CAPITAL DISTRICT. SKIES WILL 
BE MOSTLY CLOUDY FROM THE ALBANY AREA NORTH WITH PARTLY TO MOSTLY 
CLEAR SOUTH. FOR WEDNESDAY...LOOK FOR MOSTLY CLOUDY SKIES...
CONTINUED BRISK NORTHWESTERLY WINDS...AND STILL CHILLY WITH 
HIGHS 20 TO 30. A FLOW OF COLD AND MOIST AIR FROM THE MARITIMES 
AROUND THE NORTH OF THE UPPER LOW ALONG WITH LIFTING OVER THE 
ADIRONDACKS WILL RESULT IN A CHANCE OF SNOW SHOWERS OVER THE 
WESTERN AND CENTRAL ADIRONDACKS...ALONG WITH SOME POSSIBLE 
LAKE EFFECT SNOW OVER THE UPPER MOHAWK VALLEY AND THE HIGHER 
ELEVATIONS OF THE CATSKILLS. MORE OF THE SAME WEATHER WEDNESDAY
NIGHT...DRY IN THE HUDSON VALLEY WITH SLIGHT CHANCE/LOW CHANCE
POPS FOR THE ADIRONDACKS...UPPER MOHAWK VALLEY...AND THE HIGHER 
ELEVATIONS OF SOUTHERN VERMONT...THE BERKSHIRES...AND THE 
CATSKILLS.  NOT QUITE AS COLD AS TONIGHT...AGAIN BASED ON A 
BLEND OF THE MAV/MOS AND MET/MOS...WITH LOWS FROM NEAR 10 
ABOVE IN THE ADIRONDACKS TO THE MID AND UPPER TEENS IN THE
CAPITAL DISTRICT AND HUDSON VALLEY.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
A RIDGE WILL BE MOVING ACROSS REGION THURSDAY AND FRIDAY WITH A 
STACKED LOW PRESSURE SYSTEM MOVING NORTHEASTWARD ACROSS THE PLAINS 
STATES TOWARD THE WESTERN GREAT LAKES. DRY WEATHER IS EXPECTED FOR 
THURSDAY AND MUCH OF FRIDAY/CHRISTMAS WITH SEASONABLE TEMPERATURES. 
CLOUDS WILL BE IN THE INCREASE CHRISTMAS DAY AS THE LARGE LOW 
PRESSURE SYSTEM IS STILL EXPECTED TO IMPACT THE LOCAL AREA FRIDAY 
NIGHT INTO SATURDAY NIGHT.

THE GFS AND ECMWF ARE IN GENERAL AGREEMENT WITH THE MAIN SURFACE LOW 
PASSING OVER THE WESTERN GREAT LAKES...WITH A WEAK SECONDARY LOW 
TRYING TO FORM ALONG THE EAST COAST. THE MODELS HAVE TRENDED SLOWER 
BRINGING THE PRECIPITATION INTO THE LOCAL AREA. THE GFS AND ECMWF 
ARE IN AGREEMENT THE MAIN LOW WILL BE THE DOMINATE LOW...WHICH WILL 
ALLOW WARMER AIR TO WORK INTO THE AREA RESULTING IN A WINTRY MIX OF 
PRECIPITATION INCLUDING THE THREAT FOR FREEZING RAIN. HOWEVER...THE 
GFS AND ECMWF DIVERGE SATURDAY INTO SUNDAY WITH THE GFS MORE 
PROGRESSIVE WITH THE SYSTEM LIFTING IT NORTHWARD. AT THIS TIME...THE 
BEST CHANCES FOR PRECIPITATION APPEAR TO BE SATURDAY AS A STRONG LOW 
LEVEL JET...50-70 KNOTS...MOVES ACROSS THE REGION. WARMER AIR IS 
EXPECTED TO WORK DOWN TO THE SURFACE WITH A CHANGE OVER TO PLAIN 
RAIN EXPECTED SATURDAY AFTERNOON ACROSS MUCH OF THE FORECAST AREA 
WITH SOME HEAVY RAINFALL POSSIBLE. ANY CHANGES IN THE DEVELOPMENT 
AND/OR STRENGTH OF THE SECONDARY LOW WOULD HAVE A BIG IMPACT ON THE 
FORECAST/THERMAL PROFILE AND P-TYPE. AS THE SYSTEM MOVES TO OUR 
NORTH...COLDER SEASONABLE AIR WILL BE USHERED BACK INTO THE REGION 
FOR SUNDAY AND MONDAY.

WILL CONTINUE TO HIGHLIGHT THREAT OF A WINTRY MIX IN OUR HAZARDOUS 
WEATHER OUTLOOK AND KEEP MENTION OF HEAVY RAINFALL.

&&

.AVIATION /18Z TUESDAY THROUGH SATURDAY/...
VFR CONDITIONS WILL CONTINUE THROUGH THE ENTIRE TAF PERIOD. SKC WILL 
DOMINATE THE AFTN HOURS AT ALL TERMINALS. WINDS WILL REMAIN GUSTY AT 
KALB AS AIR FUNNELS DOWN THE MOHAWK VALLEY WITH GUSTS TO 25 
KTS...BUT KPOU/KGFL WILL BE SHELTERED ENOUGH FOR LIGHTER WINDS 
/GENERALLY LESS THAN 10 KTS/. 

A SLOW MOVING CUTOFF UPPER LEVEL LOW SITUATED OVER NEW ENGLAND MAY 
BEGIN TO SPREAD SOME SCT STRATO CLOUDS BACK TOWARDS THE AREA TONIGHT 
INTO WED MORN...MAINLY FOR KGFL AND KALB...BUT CONDITIONS WILL 
REMAIN VFR AND NO PRECIP IS EXPECTED. WITH THE LOSS OF DAYTIME 
HEATING...WINDS WILL DECREASE AT KALB BACK DOWN TO ABOUT 10 KTS OR 
SO FOR TONIGHT. WINDS MAY PICK UP AGAIN BY WED MIDDAY AT KALB AS THE 
PRESSURE GRADIENT REMAINS TIGHT ENOUGH FOR A FEW GUSTS TO REACH 20 
KTS...BUT WINDS AT OTHER TERMINALS SHOULD REMAIN ABOUT 10 KTS OR 
LESS.

OUTLOOK...
WED PM-FRI...VFR...NO SIG WX.
FRI NIGHT...VFR/MVFR WITH A CHANCE FOR A WINTRY MIX LATE.
SAT...MVFR-IFR WITH A WINTRY MIX LIKELY CHANGING TO RAIN.

&&

.HYDROLOGY...
NOTE...THE WATERFORD GAGE /WTFN6/ IS EXPERIENCING ICE ON THE SENSOR 
AND IS RESULTING IN INACCURATE READINGS.  RFC/USGS AND WATERFORD 
POLICE DEPARTMENT HAVE BEEN CONTACTED SINCE NO FLOODING NOR ICE JAMS 
ARE OCCURRING.  THE AHPS WEB PAGE HAS BEEN NOTATED AT THIS TIME.

THE MONITORING EQUIPMENT ON THE MOHAWK AT LITTLE FALLS HAS ALSO
BECOME FROZEN AND IT IS INOPERATIVE. GAGES ON THE MOOSE RIVER AT
MCKEEVER AND ON THE SCHOHARIE CREEK AT PRATTSVILLE ARE WORKING
BUT READING ABOUT TWO FEET HIGHER DUE TO THE EFFECT OF ICE IN 
THE RIVER. 

A COLD WEATHER PATTERN WILL CONTINUE ACROSS THE REGION THROUGH
LATE IN THE WEEK. OVER THE NEXT FOUR DAYS...TEMPERATURES ARE 
FORECAST TO AVERAGE WELL BELOW FREEZING ACROSS THE ENTIRE FORECAST 
AREA. THE COLD TEMPERATURES WILL LIKELY RESULT IN THE FORMATION OF 
AN ADDITIONAL SEVERAL INCHES OF ICE ON MANY RIVERS. ACCUMULATING ICE 
MAY CAUSE SOME RIVER LEVELS TO RISE EVEN THOUGH FLOWS CONTINUE TO 
DIMINISH.

ANY PRECIP THROUGH THURSDAY WILL BE IN THE FORM OF SNOW AND HAVE
NO DIRECT EFFECT ON THE RIVERS...WITH NO MELTING EXPECTED THROUGH
THURSDAY. A MIXED PRECIPITATION EVENT IS POSSIBLE FOR FRIDAY INTO 
SATURDAY...STARTING AS SNOW BUT MIXING AND CHANGING TO VARIOUS 
FORMS OF WINTRY PRECIP AND EVENTUALLY TO RAIN OVER MUCH OF THE
REGION ON SATURDAY. TEMPERATURES ARE FORECAST TO RISE ABOVE
FREEZING DURING THE DAY THEN DROP BACK BELOW AT NIGHT...SO AT
THIS TIME IT APPEARS THAT LITTLE...IF ANY...MELT AND RUNOFF WILL
OCCUR. BUT IT IS STILL TOO FAR INTO THE FUTURE WITH THIS TYPE OF 
STORM TO HAVE A GOOD HANDLE ON PRECIP TYPES AND QPF AMOUNTS. 

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...RCK
NEAR TERM...RCK
SHORT TERM...RCK
LONG TERM...IAA
AVIATION...FRUGIS
HYDROLOGY...RCK