MESOSCALE DISCUSSION 2264
   NWS STORM PREDICTION CENTER NORMAN OK
   0613 PM CST TUE DEC 22 2009
   
   AREAS AFFECTED...NRN ME
   
   CONCERNING...HEAVY SNOW 
   
   VALID 230013Z - 230545Z
   
   MODERATE TO LOCALLY HEAVY SNOW WILL PERSIST THIS EVENING THROUGH THE
   OVERNIGHT WITHIN A QUASI-STATIONARY NW TO SE-ORIENTED BAND. SNOWFALL
   RATES WITHIN THE BAND SHOULD REACH 1 IN/HR AT TIMES.
   
   RECENT RADAR IMAGERY HAS DEPICTED SNOW IN AN INCREASINGLY
   BANDED/CONTRACTED STRUCTURE FROM COASTAL WASHINGTON COUNTY NWWD INTO
   NRN PISCATAQUIS COUNTY. MODERATE TO HEAVY SNOW HAD LIKELY COMMENCED
   WITHIN THIS BAND /REF KMLT 2309Z METAR ON FAR WRN EDGE OF BAND/.
   AFTERNOON MODEL FORECASTS ARE CONSISTENT THAT THE VIGOROUS SHORT
   WAVE TROUGH OVER WRN NEW ENGLAND WILL ONLY SLOWLY SHIFT
   EWD...RESULTING IN SUBSTANTIAL 900-700 MB FRONTOGENETICAL FORCING
   REMAINING NEARLY STATIONARY THROUGH EARLY WED. THIS WILL LIKELY LEAD
   TO SUSTAINED PERSISTENCE OF THE BAND WELL INTO THE OVERNIGHT...WITH
   SOME OSCILLATORY DRIFT WHICH IS SUPPORTED BY HI-RES WRF REFLECTIVITY
   GUIDANCE. THE FRONTOGENETIC FORCED ASCENT WILL BE JUXTAPOSED WITH A
   LARGE DENDRITIC GROWTH LAYER /AOA 100 MB DEPTH/...ESPECIALLY ON THE
   SRN PORTION OF THE BAND WHERE THERMODYNAMIC PROFILES WILL REMAIN
   COOLER THAN FARTHER N. SNOWFALL RATES AROUND 1 IN/HR SHOULD OCCUR AT
   TIMES...AMIDST A LONG DURATION EVENT.
   
   ..GRAMS.. 12/23/2009
   
   
   ...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...CAR...
   
   LAT...LON   45066687 44676702 44766734 45576857 46446974 46896982
               47126952 46886902 46376818 45066687