FXUS61 KBGM 062100
AFDBGM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BINGHAMTON NY
400 PM EST SUN DEC 6 2009

.SYNOPSIS...
HIGH PRESSURE OVER THE MID ATLANTIC STATES WILL MAINTAIN A SEASONABLY
COLD WESTERLY FLOW OVER CENTRAL NEW YORK AND NORTHEAST
PENNSYLVANIA TONIGHT. LAKE EFFECT SNOW SHOWERS ARE EAST OF LAKE
ONTARIO AND NORTH OF THE THRUWAY. A WEAK SYSTEM WITH LIGHT SNOW
SHOWERS WILL MOVE THROUGH MONDAY AFTERNOON INTO TUESDAY. A MAJOR
STORM SYSTEM WILL BRING SIGNIFICANT MIXED PRECIPITATION TO THE
REGION LATE TUESDAY NIGHT INTO WEDNESDAY.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
HIGH PRESSURE OVER THE MID ATLANTIC STATES WILL REMAIN IN CONTROL
INTO MONDAY. LOW LEVEL FLOW IS SHIFTING FROM WEST TO SW LATE THIS
AFTN INTO TONIGHT. LAKE EFFECT SHOWERS HAVE GREATLY DIMINISHED OFF
OF LAKE ERIE WHILE THE BAND EAST OF LAKE ONTARIO INTO ONEIDA
COUNTY HAS ALSO WEAKENED. THERE IS NO LONGER A CONNECTION TO LAKE
HURON AND THE BAND IS STARTING CLOSER TO THE EAST END OF THE LAKE. 
THE LAKE EFFECT BAND IS EXPECTED TO REMAIN WEAK WITH LIGHT SNOW
SHOWERS TONIGHT INTO MONDAY MORNING. THE BAND WILL SHIFT NORTH OF
THE CWA TOWARD MIDNIGHT. MAYBE ANOTHER INCH THIS EVENING THERE.

FOR THE REST OF THE AREA FEW CLOUDS THIS EVENING SO WITH CLEAR
SKIES AND SNOW ON THE GROUND TEMPS WILL FALL FAST. MID AND HIGH
CLOUDS WILL MOVE IN DURING THE OVERNIGHT. 

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/...
MONDAY WILL START OUT DRY AND MOSTLY CLOUDY. A WEAK SYSTEM WILL
MOVE THROUGH FROM MON AFTN TO TUESDAY. THE BEST DYNAMICS ARE EARLY
WHILE THE MOISTURE TAKES ITS TIME TO RETURN. MODELS NOT
CONSISTENT ON THE TIMING BUT AGREE THAT THIS WILL BE WEAK. HAVE
STAYED WITH CHC POPS MOSTLY ACROSS NY. QPF UNDER A TENTH AND
SNOWFALL OF LESS THAN HALF AN INCH. 

BEHIND THIS SYSTEM THE FLOW SHIFTS TO 290 LATE MON NGT TO TUESDAY
SO SOME LAKE EFFECT WILL START. THIS SHOULD BE WEAK WITH MARGINAL
TEMP DIFFERENCES.  

A BRIEF BREAK TUE EVE THEN THE BIG STORM FOR THE WEEK ARRIVES
DURING THE OVERNIGHT. THIS STRONG INTENSIFYING STORM WILL MOVE
INTO THE WRN GREAT LAKES THEN TO SRN ONTARIO WED. PRECIP WILL
SPREAD RAPIDLY NE THROUGH THE AREA BY 12Z AND START AS SNOW. WITH
THE DEEP STRONG SW FLOW SNOW WILL CHANGE QUICKLY TO RAIN MIDDAY
BEFORE ENDING LATE WED. QPF AMOUNTS BETWEEN HALF AN INCH AND AN
INCH SO SEVERAL INCHES OF SNOW ARE EXPECTED BEFORE THE TURNOVER.
HIGHLIGHTING THE STORM IN THE HWO BUT STILL TOO MUCH UNCERTAINTY
TO PUT IN AMOUNTS. MODELS AGREE THAT WE WILL HAVE A STRONG
MOISTURE LADEN FRONT GO THROUGH WED AM BUT THE UNCERTAINTY WILL BE
HOW MUCH AND WHAT TYPE OF PRECIP. 

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
EXTENDED FORECAST WILL BE DOMINATED BY A BROAD UPPER LEVEL TROF
WITH THE COLDEST AIRMASS OF THE SEASON ACROSS THE NORTHEAST
THROUGH LATE WEEK. TOWARD THE END OF THE PERIOD UPPER TROF RELAXES
AS FLOW BECOMES MORE ZONAL. WITH DEEP CYCLONIC FLOW CONTINUED WITH
CHC/LIKELY POPS FOR SNOW SHOWERS, WITH LIKELY POPS CONFINED TO NRN
CWA WHERE LAKE EFFECT SNOW BAND MAY RESIDE. ATTM FLOW DURING
COLDEST PART OF PERIOD MAY BE TOO SOUTHWEST WITH BEST LAKE EFFECT
ACTIVITY REMAINING JUST NORTH OF ONEIDA COUNTY. TOWARD THE END OF
THE PERIOD BUILDING SFC RIDGE AND MODERATING AIRMASS WILL LESSEN
THE LIKELIHOOD OF LAKE ACTIVITY. TEMPS WILL RUN BELOW NORMAL.

&&

.AVIATION /21Z SUNDAY THROUGH FRIDAY/...
AT KRME, LAKE EFFECT SNOW BAND ACROSS NRN ONEIDA COUNTY WILL
PRODUCE MVFR WITH OCCASIONAL IFR CONDITIONS THROUGH LATE AFTERNOON.
REST OF TERMINALS WITH HAVE SCT/BKN CLOUDS AROUND 4K FT THROUGH
EARLY EVENING. REST OF PERIOD WEAK CLIPPER WILL MOVE ACROSS LOWER
LAKES BUT BULK OF MOISTURE WILL REMAIN NORTH OF TERMINALS. MAINLY
JUST SCATTERED MID CLOUDS OVERNIGHT DEVELOPING INTO A MID DECK BY
MONDAY MORNING.

WESTERLY WINDS THIS AFTERNOON AT 10 KNOTS WITH GUSTS AROUND 15
KNOTS BECOMING SOUTHWEST THIS EVENING AROUND 5 KNOTS THEN S/SE
LATE TONIGHT AND MONDAY.

OUTLOOK...

MON NGT/TUE...POSSIBLE MVFR IN SNOW SHOWERS, MAINLY KRME/KSYR.
TUE NGT...MVFR/IFR LATE IN SNOW.
WED...MVFR/IFR IN MIXED PRECIP.
WED NGT THRU FRIDAY...OCCASIONAL MVFR/IFR IN LAKE EFFECT SNOW
SHOWERS PRIMARILY KRME/KSYR.

&&

.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.

&&

$$
SYNOPSIS...TAC
NEAR TERM...TAC
SHORT TERM...TAC
LONG TERM...RRM
AVIATION...RRM