MESOSCALE DISCUSSION 2616 NWS STORM PREDICTION CENTER NORMAN OK 0944 PM CST SUN DEC 14 2003 AREAS AFFECTED...ERN MA...SRN NH...EXTREME SWRN ME CONCERNING...PRECIPITATION TRENDS...WINTER PRECIPITATION VALID 150344Z - 150845Z STRONG NOREASTER NEAR ACY TO TRACK TOWARD LONG ISLAND OVER THE NEXT 6 HOURS WHILE DEEPENING RAPIDLY. SURFACE FREEZING LINE HAS BEEN MAKING STEADY PROGRESS INLAND ACROSS SRN NEW ENGLAND AND SHOULD CONTINUE TO SLOWLY WORK NWWD ACROSS INTERIOR NERN MA AND SERN NH THROUGH 15/09Z BASED ON LATEST ENSEMBLE FORECASTS AND OBSERVED TRENDS. EXTREME BAROCLINICITY OF THIS SYSTEM HAS RESULTED IN A VERY NARROW PTYPE TRANSITION ZONE ACROSS CT AND ERN MA THIS EVENING WITH SNOW CHANGING TO RAIN WITHIN AN HOUR OR SO AFTER THE SURFACE TEMPERATURES REACH 32F...AND A MIX OF SLEET AND SNOW MOST COMMON IN A 50-80 MILE BAND NORTH OF THE SURFACE FREEZING LINE. STRONGEST LOW LEVEL WARM NOSE ABOVE THE SURFACE SHOULD CONTINUE TO DEVELOP NEWD FROM ERN MA INTO SRN NH AND EXTREME SWRN ME OVER THE NEXT 3-6 HOURS AIDED BY 70-80KT ELY LOW LEVEL JET. THIS SHOULD CAUSE PRECIPITATION TO CHANGE FROM SLEET AND SNOW TO FREEZING RAIN ACROSS INTERIOR AREAS FROM ORH TO NW OF PSM...WITH PRIMARILY RAIN EAST OF THIS LINE. NORTHWEST SECTIONS OF THE AREA /SEE GRAPHIC/ SHOULD CONTINUE TO EXPERIENCE PRIMARILY SNOW AND SLEET WITH PRECIPITATION AMOUNTS GRADUALLY DIMINISHING FROM SW TO NE LATE TONIGHT INTO EARLY MONDAY MORNING. ..CARBIN.. 12/15/2003 ATTN...WFO...GYX...BOX...ALY... 43267036 42337089 42097219 42437266 42947244 43307121
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