FXUS61 KALY 300542
AFDALY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
1242 AM EST MON NOV 30 2009

.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL MOVE ACROSS THE REGION TONIGHT AND MONDAY 
BRINGING RAIN SHOWERS TO THE AREA. AS COOLER AIR FLOWS IN BEHIND 
THIS SYSTEM THE SHOWERS MAY MIX WITH AND CHANGE TO SNOW IN THE 
AFTERNOON. A MORE SEASONABLE AIRMASS WILL BE USHERED IN BEHIND THIS 
SYSTEM WITH SOME LAKE EFFECT SNOW EXPECTED ACROSS PORTIONS THE 
WESTERN ADIRONDACKS MONDAY NIGHT AND TUESDAY. HIGH PRESSURE WILL 
BUILD IN TUESDAY NIGHT AND SHOULD DOMINATE OUR WEATHER WEDNESDAY. 
MORE PRECIPITATION...MAINLY RAIN...IS EXPECTED WEDNESDAY NIGHT AND 
THURSDAY AS ANOTHER STORM SYSTEM APPROACHES FROM THE SOUTH.

&&

.NEAR TERM /THROUGH TODAY/...
TWO MESONET TYPE SITES...STILLWATER RESERVOIR AND OLD FORGE...
IN THE WESTERN ADIRONDACKS EXPERIENCED TEMPERATURE RISES OF 
AROUND 5 DEGREES IN THE PAST HOUR OR TWO...WITH CLOUDS AND 
WARMER AIR STREAMING IN FROM THE WEST. MEANWHILE...TEMPERATURES
IN THE HUDSON VALLEY...KGFL...KALB...AND KPOU...WERE SEVERAL 
DEGREES COOLER THAN FORECAST AT THIS TIME. FEELING IS THAT 
TEMPERATURES IN THE HUDSON VALLEY AND EAST MAY DROP A DEGREE
OR TWO IN THE NEXT TWO HOURS...THEN RISE SOME DURING THE EARLY
MORNING HOURS WHILE FARTHER NORTHWEST THEY WILL NOT SHOW MUCH  
CHANGE. THE 00Z ALY SOUNDING WAS WELL ABOVE ZERO THROUGH 800 HPA
AND THE BUF SOUNDING WELL ABOVE ZERO THRU 850. WITH LOW LEVEL 
WINDS SW/WSW...FEEL PRECIP OVERNIGHT WILL BE ALL LIQUID SO HAVE
REMOVED MENTION OF SNOW FOR OVERNIGHT PERIODS. HAVE ALSO UPDATED
SKY COVER PER LATEST OBS AND SAT IMAGES...AND BASED ON RADAR 
HAVE MOVED THE POPS A BIT FARTHER SOUTH FOR THE EARLIER PERIODS. 
OVERNIGHT LOWS WILL RANGE FROM THE MID 30S ACROSS THE HUDSON 
VALLEY NORTH OF ALBANY AND OVER SOUTHERN VERMONT TO THE LOW
40S ACROSS THE WESTERN MOHAWK VALLEY AND THE HUDSON VALLEY 
SOUTH OF ALBANY...AND NEAR 40 ACROSS THE WESTERN ADIRONDACKS
WHERE WARM AIR ADVECTION WAS ALREADY TAKING PLACE AND LOW 
CLOUDS WILL INHIBIT ANY RADIATIONAL COOLING.

THE RIDGE OVER THE AREA WILL SHIFT EAST OFFSHORE THIS EVENING AND A 
LOW PRESSURE SYSTEM OVER THE GREAT LAKES WILL MOVE EAST ACROSS THE 
LOCAL AREA LATE TONIGHT AND MONDAY MORNING. CLOUDS WILL BE ON THE 
INCREASE THIS EVENING. MOST OF THE PRECIPITATION ASSOCIATED WITH THE 
SYSTEM WILL OCCUR ALONG AND BEHIND THE COLD FRONT WITH THE UPPER 
LEVEL SUPPORT WHICH LAGS. LONGWAVE TROUGH DIGS IN OVER REGION DURING 
THE DAY MONDAY. TEMPERATURES WILL DROP DURING THE AFTERNOON IN THE 
COLD AIR ADVECTION. THE 850 MB 0C ISOTHERM REACHES THE MID/LOWER 
HUDSON VALLEY BY EARLY AFTERNOON AND MOVES OFFSHORE...SOUTH OF LONG 
ISLAND...BY EARLY EVENING. HIGHS WILL RANGE FROM THE UPPER 30S 
ACROSS THE HIGHER TERRAIN OF SOUTHERN VT AND NEAR 40 ACROSS THE
ADIRONDACKS...WHERE THE HIGH WILL PROBABLY OCCUR BEFORE NOON...
TO THE LOWER 50S IN THE HUDSON VALLEY SOUTH OF ALBANY.

&&

.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
ADDITIONAL SHORT WAVE ENERGY DIVES INTO THE TROUGH MONDAY NIGHT AS 
SURFACE HIGH TRIES TO BUILD IN. THE UPPER TROUGH AXIS MOVES TO OUR 
EAST TUESDAY MORNING WITH CYCLONIC FLOW ACROSS THE REGION. LAKE 
ONTARIO SURFACE WATER TEMPERATURE IS IN THE UPPER 40S AND WITH THE 
COLDER MORE SEASONABLE AIRMASS BEING USHERING IN SOME LAKE EFFECT 
SHOWERS ARE EXPECTED ACROSS PORTIONS OF THE WESTERN ADIRONDACKS WITH 
WESTERLY LOW LEVEL FLOW TUESDAY. LIGHT SNOW ACCUMULATIONS OF 1 TO 2 
INCHES ARE EXPECTED AT THIS TIME. THE LAKE EFFECT WILL GET CUT OFF
AS RIDGING BUILDS AT THE SURFACE AND ALOFT TUESDAY NIGHT. THE RIDGE
IS EXPECTED TO DOMINATE OUR WEATHER WEDNESDAY WITH A STORM
APPROACHING FROM THE SOUTH.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
THE DETERMINISTIC LONG RANGE GUIDANCE /ECMWF...GFS...CANADIAN GGEM/ 
AND THE ENSEMBLES CONTINUE TO INDICATE A STORM SYSTEM INTERACTING 
WITH THE SUBTROPICAL JET STREAM WILL APPROACH FROM THE TN AND OH 
VALLEYS WED NIGHT.  THIS SYSTEM WILL BE UTILIZING GULF OF MEXICO 
MOISTURE.  THE EXACT TRACK OF THE INTENSIFYING LOW PRESSURE SYSTEM 
IN THE SOUTHWEST FLOW ALOFT IS STILL VARIABLE FROM THE 
GUIDANCE...THOUGH THE 12 GEFS MEAN BRINGS THE LOW ACROSS E-CNTRL PA 
AND OVER THE CAPITAL REGION BTWN 12Z-18Z THU.  THERE IS QUITE A BIT 
OF SPREAD WITH A FEW MEMBERS AS FAR WEST AS ERN MI...AND AS FAR 
SOUTH AND EAST TO THE DELMARVA REGION.  THE ENSEMBLE MEAN MSLP OF 
THE SFC CYCLONE IS 988 HPA...SO A DEEPENING AND INTENSIFYING WAVE IS 
IMPLIED.  HOWEVER...THERE IS NOT A COLD CANADIAN ANTICYCLONE TO THE 
NORTH ENTRENCHING COLD AIR AHEAD OF THE WAVE.  THE THERMAL PROFILES 
ARE WARM FOR PREDOMINANTLY AN ALL RAIN EVENT FOR THE HEART OF THE 
EVENT.  A MOISTURE RICH LOW LEVEL BAROCLINIC ZONE SHOULD YIELD SOME 
PERIODS OF RAIN /POSSIBLY MODERATE TO HVY AT TIMES/ WEDNESDAY NIGHT 
INTO THURSDAY...AND WE HAVE ADDRESSED THE BETTER CHANCES OF RAIN 
WITH LIKELY POPS FCST AREA WIDE ON THU.

THU NIGHT INTO FRI...THE STRONG SFC WAVE ACCELERATES NORTHEAST AS IT 
REMAINS AN OPEN WAVE ALOFT.  STRONG COLD AIR ADVECTION OCCURS IN THE 
WAKE OF THE SYSTEM WITH SOME LAKE ENHANCED PCPN POSSIBLE FOR THE WRN 
PORTION OF THE FCST AREA. H850 TEMPS TUMBLE TO AROUND -10C FOR THE 
BULK OF THE FCST AREA.

SATURDAY...BROAD CYCLONIC FLOW PERSISTS TO OPEN THE WEEKEND WITH 
COLD AIR FUNNELING SOUTHEAST TOWARDS THE REGION FROM THE S-CNTRL 
ONTARIO.  SOME LAKE EFFECT -SHSN/S WILL PERSIST WEST OF THE HUDSON 
RIVER VALLEY.

SATURDAY NIGHT INTO SUNDAY...THE LOW LEVEL FLOW BEGINS TO SHIFT AND 
BECOME ANTICYCLONIC WITH SFC HIGH PRESSURE NOSING IN FROM THE OH 
VALLEY/MID ATLANTIC REGION.  TEMPS WILL MODERATE TO NEAR NORMAL 
VALUES FOR EARLY DEC.  MOST OF THE FCST AREA LOOKS LIKE IT WILL HAVE 
A FAIRLY DRY WEEKEND AT THIS POINT IN TIME.

OVERALL...PCPN LOOKS ABOVE NORMAL BASED ON THE STORM SYSTEM FOR 
THU...AND TEMPS WILL BE NEAR NORMAL OR SLIGHTLY BELOW NORMAL FOR THE 
STRETCH.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS WILL GRADUALLY GIVE WAY TO MVFR CONDITIONS DURING
THE REMAINDER OF THE OVERNIGHT PERIOD AS SHOWERS OVERSPREAD THE
UPPER HUDSON VALLEY WHICH WILL IMPACT KGFL AND KALB. KPOU IS
LIKELY TO REMAIN VFR DURING THE REMAINDER OF THE OVERNIGHT PERIOD
WITH SHOWERS NOT ARRIVING UNTIL BETWEEN 10Z AND 12Z. TAF SITES
LOOK TO GO IFR AFTER COLD FRONTAL PASSAGE FOR SEVERAL HOURS WHICH
IS EXPECTED AROUND 13Z AT KGFL...14Z AT KALB AND 16Z AT KPOU. THIS
WILL BE FOLLOWED BY IMPROVING CONDITIONS TO VFR AND EVENTUALLY
CLEARING EARLY THIS EVENING AT KGFL AND KALB WITH STRATOCUMULUS
VFR CEILINGS AT KPOU THROUGH THE END OF THE TAF PERIOD AT KPOU.

LIGHT WINDS WILL BECOME SOUTH AT 4 TO 8 KTS AT TAF SITES DURING
THE REMAINDER OF THE OVERNIGHT PERIOD AND THEN SHIFT TO W-SW
AROUND 5 TO 8 KTS WITH COLD FRONTAL PASSAGE BETWEEN 13Z AND 16Z
AND EVENTUALLY NORTHWEST AT 4 TO 8 KTS BETWEEN 16Z AND 22Z.
 
OUTLOOK... 
MON NIGHT-WED...VFR. NO SIG WX. 
WED NIGHT-THU...MVFR-IFR. RA LIKELY.
FRI...VFR...CHC -SHRA/-SHSN.

&&

.HYDROLOGY...
NO WIDESPREAD HYDRO PROBLEMS ARE ANTICIPATED THE NEXT FIVE DAYS. A 
COLD FRONT AND A WEAK WAVE OF LOW PRESSURE WILL BRING LIGHT PCPN TO 
THE HYDRO SERVICE AREA /HSA/ SUNDAY NIGHT THRU MONDAY IN THE FORM OF 
RAIN AND SNOW SHOWERS.  TOTAL QPF WILL RANGE FROM A TENTH TO A THIRD 
OF AN INCH.
  
HIGH PRESSURE WILL YIELD MAINLY DRY WEATHER TUESDAY THROUGH 
WEDNESDAY...EXCEPT FOR SOME LIGHT LAKE EFFECT SNOW WHICH WILL BE 
MAINLY CONFINED TO THE WESTERN ADIRONDACKS LATE MONDAY NIGHT INTO 
TUESDAY EVENING.

A STORM SYSTEM APPROACHING FROM THE OH VALLEY WEDNESDAY NIGHT MAY 
BRING A SOAKING RAINFALL TO THE HSA THU WITH RAINFALL AMOUNTS 
RANGING FROM A HALF AN INCH TO AN INCH AND A HALF. 

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...IAA/RCK
NEAR TERM...IAA/RCK
SHORT TERM...IAA
LONG TERM...WASULA
AVIATION...11
HYDROLOGY...WASULA