MESOSCALE DISCUSSION 0142
   NWS STORM PREDICTION CENTER NORMAN OK
   1114 PM CST SUN FEB 22 2009
   
   AREAS AFFECTED...MOST OF ME
   
   CONCERNING...HEAVY SNOW 
   
   VALID 230514Z - 230915Z
   
   HEAVY SNOW...WITH RATES AS HIGH AS 1-3 IN/HR...WILL BE LIKELY OVER
   PORTIONS OF ME DURING THE MORNING. THE HEAVIEST SNOWFALL IS EXPECTED
   TO SHIFT INTO ERN-NERN ME AFTER 09Z.
   
   A POTENT NEG TILT S/W TROUGH MOVING NE ACROSS THE CAPE COD REGION AT
   04Z...IS FORECAST TO ROTATE INTO NEW BRUNSWICK/NOVA SCOTIA BY
   12-15Z/MON. STRONG UPPER LEVEL DIVERGENCE AND SYNOPTIC SCALE ASCENT
   /EVIDENT BY HOURLY PRESSURE FALLS OF 5 MB OFF THE COAST OF ME/ WILL
   ACCOMPANY THIS FEATURE...FAVORING DEEPLY SATURATED ENVIRONMENT OVER
   ME. 00Z UPPER AIR OBSERVATIONS DEPICT A 30-40 KT 850 MB JET
   IMPINGING UPON A TIGHT THERMAL GRADIENT PRESENT OVER NEW
   ENGLAND...FOCUSING INTENSE LOW LEVEL WAA AND FRONTOGENESIS ALONG A
   LINE FROM LCI TO 50S OF HUL...WHERE REGIONAL REFLECTIVITY AT 05Z
   DEPICTS A BAND OF MODERATE TO HEAVY SNOW. 
   
   RUC AND SREF MODEL GUIDANCE INDICATE THE LOW LEVEL JET WILL REORIENT
   FROM A EPM TO AUG POSITION AT 06Z...TO MORE OF A ENE POSITION
   IMPINGING UPON HUL BY 12Z. THIS SHOULD LEAD TO A GRADUAL SHIFT IN
   STRONGEST MESOSCALE UVV/S FROM THE SRN HALF OF ME /AND A
   CORRESPONDING DECREASE IN SNOWFALL INTENSITY/ TOWARD ERN-NERN ME BY
   09-12Z...WHERE 1-3 IN/HR RATES WILL BE POSSIBLE AFTER 09Z.
   
   ..GARNER.. 02/23/2009
   
   
   ...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...GYX...
   
   LAT...LON   44477088 45377020 46636904 47426819 47066768 45846765
               45416738 45036749 44646866 44166987 43487065 43437100
               43927100 44477088