[MCD] SWOMCD

Sun Feb 12 06:52:35 UTC 2006

ACUS11 KWNS 120651
SWOMCD
SPC MCD 120651 
MAZ000-RIZ000-CTZ000-NYZ000-NJZ000-PAZ000-DEZ000-MDZ000-DCZ000-VAZ000-121145-

MESOSCALE DISCUSSION 0138
NWS STORM PREDICTION CENTER NORMAN OK
1251 AM CST SUN FEB 12 2006

AREAS AFFECTED...DELMARVA...SE PA/NJ INTO SRN NEW ENGLAND

CONCERNING...HEAVY SNOW AND BLIZZARD CONDITIONS 

VALID 120651Z - 121145Z

MODERATE AND HEAVY SNOW BANDS WILL SPREAD SLOWLY NORTHEAST ALONG THE
I-95 CORRIDOR FROM FAR NE VA/CNTRL MD THROUGH SE PA/NRN NJ AND SE NY
OVERNIGHT...WITH SNOW INTENSIFYING ACROSS SRN NEW ENGLAND. SNOWFALL
RATES OF 1 TO 2 IN PER HR WILL OCCUR ACROSS MUCH OF THIS AREA. LOCAL
RATES UP TO 3 IN PER HR WILL BE POSSIBLE. BLIZZARD CONDITIONS WILL
DEVELOP CLOSER TO THE ATLANTIC COAST WITH WIND SPEEDS OF 3O TO 40
MPH AND MODERATE TO OCCASIONALLY HEAVY SNOWFALL.

CLASSIC NOREASTER WILL TAKE SHAPE TODAY AS SURFACE LOW PRESSURE
DEEPENS OFF THE MD/VA COAST AND LIFTS NORTHEAST. INTENSE LOW AND
MID-LEVEL ISENTROPIC LIFT WILL OCCUR OVERNIGHT FROM THE DELMARVA
NORTHEAST TOWARDS CAPE COD. STRONG FRONTOGENETICAL FORCING FROM 700
TO 600 MB AROUND 100 MILES TO THE NW FROM IAD TO PTW TO HPN WILL
RESULT IN SIGNIFICANT LIFT IN THE DENDRITIC GROWTH ZONE. BANDED
PRECIP HAS TAKEN SHAPE IN THIS DEFORMATION AREA AND WILL SLOWLY
SHIFT NORTHEAST OVERNIGHT. ELEVATED POTENTIAL INSTABILITY WILL
RESULT IN A FEW CONVECTIVE BANDS WHERE SNOWFALL RATES COULD REACH 3
IN PER HR...AS EVIDENCED BY RECENT THUNDERSNOW IN THE PHL METAR AND
NLDN LIGHTNING STRIKES. 

CLOSER TO THE COAST...RUC AND NAM 850 MB PROGS STRENGTHEN THE
LOW-LEVEL COLD CONVEYOR BELT WITH 55 TO 65 KT NE WINDS BY 12Z. THIS
STRENGTHENING IS ALREADY EVIDENT IN THE DOX AND DIX VAD PROFILERS.
SURFACE WIND SPEEDS WILL ALSO INCREASE IN RESPONSE TO THIS AND A
TIGHTER PRESSURE GRADIENT. AS A RESULT...WIND SPEEDS OF 30 TO 40 MPH
ARE LIKELY. COMBINED WITH MODERATE TO OCCASIONALLY HEAVY
SNOWFALL...BLIZZARD CONDITIONS WILL DEVELOP...ESPECIALLY TOWARDS
12Z.

..GRAMS/GUYER.. 02/12/2006

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

ATTN...WFO...BOX...OKX...ALY...PHI...BGM...CTP...LWX...

39347757 40427679 41337525 42087400 42587277 42607135
41687002 41347080 41277167 40917252 40537394 39727457
39117548 38797598 38647635 38467741 

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