[MCD] SWOMCD

[Mesoscale Convective Discussions]

ACUS11 KWNS 051048
SWOMCD
SPC MCD 051048 
NYZ000-051545-

MESOSCALE DISCUSSION 2271
NWS STORM PREDICTION CENTER NORMAN OK
0448 AM CST TUE DEC 05 2006

AREAS AFFECTED...ALONG AND JUST SOUTH OF TUG HILL REGION

CONCERNING...HEAVY SNOW 

VALID 051048Z - 051545Z

LAKE EFFECT SNOW BAND WITH RATES OF 1-3 INCHES WILL CONTINUE TO
BECOME ORIENTED ALONG THE MAJOR-AXIS OF LAKE ONTARIO THROUGH MID
MORNING...WITH THE GREATER SNOWFALL RATES BEGINNING TO AFFECT SRN
JEFFERSON AND OSWEGO COUNTIES BY 11-12Z.  THIS BAND IS EXPECTED TO
REMAIN FOCUSED INTO THE TUG HILL REGION THIS MORNING.  THE SRN PART
OF THIS BAND MAY SHIFT JUST S OF TUG HILL REGION INTO NRN PARTS OF
ONONDAGA TO ERN WAYNE COUNTIES LATER THIS MORNING AS LOW LEVEL WINDS
SHIFT TO THE WNW. 

SINCE 08-09Z...RADAR AND SATELLITE IMAGERY INDICATED A LAKE EFFECT
SNOW BAND DEVELOPING ALONG THE MAJOR-AXIS OF LAKE ONTARIO /CENTRAL
PORTIONS OF THE LAKE/. LOW LEVEL CONVERGENCE...PER STREAMLINE
ANALYSIS...HAS INCREASED THUS FAR AS LOW LEVEL WINDS OVER THE WRN
AND CENTRAL PARTS OF LAKE ONTARIO HAVE SHIFTED TO THE WEST WITH THE
PASSAGE OF A SHORT WAVE TROUGH.  AS THIS TROUGH CONTINUES TO TRACK E
TOWARD NEW ENGLAND THIS MORNING...THE LOW LEVEL WINDS OVER ERN LAKE
ONTARIO WILL ALSO SHIFT TO THE W ALLOWING THIS SNOW BAND TO SPREAD
INLAND OVER JEFFERSON AND OSWEGO COUNTIES BY 11-12Z.  THE TUG HILL
REGION SHOULD BE THE PRIMARY FOCUS FOR THIS BAND THROUGH 17-18Z...
THOUGH A WIND SHIFT TO THE WNW MAY ALLOW THE BAND TO SETTLE SLIGHTLY
SWD INTO NRN PARTS OF ONONDAGA...CAYUGA TO ERN WAYNE COUNTIES DURING
THE LATE MORNING. 

IR IMAGERY INDICATED COOLING CLOUD TOPS WITH THIS DEVELOPING SNOW
BAND OVER LAKE ONTARIO...WITH CLOUD TOPS ESTIMATED IN EXCESS OF
12-14 KFT AND THUS FAVORABLE FOR CHARGE SEPARATION /I.E. LIGHTNING
PRODUCTION/.  ALTHOUGH INVERSION HEIGHTS ARE EXPECTED TO FALL TO
AROUND 8 KFT BY 18Z...STEEP LOW LEVEL LAPSE RATES AND LAKE-INDUCED
CAPE OF 100-300 J/KG SUGGESTS POTENTIAL FOR GREATER SNOWFALL RATES
WITH CONVECTIVE ELEMENTS.

..PETERS.. 12/05/2006

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

...NOTICE...
SPC WINTER WEATHER MESOSCALE DISCUSSIONS WILL BE ISSUED ON A
SCHEDULED BASIS FROM DECEMBER 1 THROUGH FEBRUARY 28...FOUR
TIMES A DAY...AROUND 00 UTC...06 UTC...12 UTC...AND 18 UTC
FOR SIGNIFICANT SHORT RANGE WINTER WEATHER EVENTS.

ATTN...WFO...BGM...BUF...

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