MESOSCALE DISCUSSION 0097
   NWS STORM PREDICTION CENTER NORMAN OK
   1027 AM CST THU JAN 25 2007
   
   AREAS AFFECTED...NERN OH...FAR NWRN PA
   
   CONCERNING...HEAVY SNOW 
   
   VALID 251627Z - 252230Z
   
   SNOWFALL RATES WITH ONGOING LES BANDS SHOULD INTENSIFY OVER FAR NERN
   OH AND FAR NWRN PA THROUGH 18Z. HRLY SNOWFALL RATES UP TO 2 INCHES
   ARE ANTICIPATED IN THE MOST WELL ORGANIZED LES BAND/S. HEAVIEST SNOW
   FALL RATES SHOULD LAST UNTIL AROUND 22Z...WITH A  DIMINISHING TREND
   EXPECTED THEREAFTER.
   
   A LES BAND OVER ASHTABULA COUNTY OHIO WILL GRADUALLY MOVE EWD INTO
   ERIE AND CRAWFORD COUNTIES PA OVER THE NEXT 1-2 HRS. THIS WILL OCCUR
   IN RESPONSE TO AN APPROACHING MESOSCALE VORT CENTER /MVC/ LOCATED
   OVER SWRN ONTARIO /40 E OF PORT HURON MI/ MOVING SEWD AROUND 25 KTS
   ALONG AN INVERTED SFC TROUGH. ALTHOUGH AN INCREASE IN LOW LEVEL
   SHEAR IS ANTICIPATED AS WINDS OFF THE SURFACE BACK WITH THE APPROACH
   OF THIS MVC...INCREASING LIFT AND DEEPENING INVERSION HEIGHTS TO
   BETWEEN 8-10 KFT SHOULD COUNTERACT THE AFFECTS OF THE INCREASED
   SHEAR. THUS MULTIPLE BANDS OF HVY SNOW ARE APT TO DEVELOP/INTENSIFY
   OVER NERN OH/FAR NWRN PA IN THE NEXT 2-3 HRS AHEAD OF THIS MVC
   MOVING OUT OF SWRN ONTARIO. THE MOST INTENSE SNOWBANDS MAY BE
   CAPABLE OF 2 INCH/HR SNOWFALL RATES...ESPECIALLY ALONG THE PATH OF
   THE MVC /INTO ASHTABULA COUNTY OH AND ERIE COUNTY PA/ SUPPORTED BY
   15-20:1 SNOW/WATER RATIOS AND STEEP LOW LEVEL LAPSE RATES. WITH THE
   DEPARTURE OF THE MVC...MULTIPLE LES BAND SHOULD BRIEFLY MOVE
   WWD...BUT DECREASING LOW LEVEL SHEAR AND LONG LAKE FETCH OFF SRN
   LAKE HURON SHOULD SUPPORT A SINGLE LES BAND OVER LAKE ERIE INTO THE
   ERN CLE METRO AREA AR0UND 20Z. THIS SNOW BAND WILL BE CAPABLE OF
   HRLY SNOWFALL RATES FROM 1-2 INCHES. SWD MOVING ARTIC AIR AND
   FALLING INVERSION HEIGHTS WILL PUSH INTO THE AREA BEGINNING AROUND
   22Z...WITH NOTICEABLY LOWER SNOWFALL RATES EXPECTED AROUND 00Z.
   
   ..CROSBIE.. 01/25/2007
   
   
   ...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...PBZ...CLE...
   
   42077984 42178001 41638168 41158151 41148101 41498024
   41897973