000
FXUS01 KWBC 092105
PMDSPD
 
SHORT RANGE FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
404 PM EST THU FEB 09 2012
 
VALID 00Z FRI FEB 10 2012 - 00Z SUN FEB 12 2012
 
...ARCTIC AIR WILL SPREAD ACROSS MUCH OF THE EASTERN THIRD OF THE
COUNTRY IN THE NEXT COUPLE OF DAYS FOLLOWED BY A LARGE DEVELOPING
STORM OFF THE EAST COAST...

...PRECIPITATION EXPECTED TO PERSIST THROUGH SATURDAY IN THE
PACIFIC NORTHWEST...

THE FORECAST PERIOD BEGINS WITH THE LEADING EDGE OF AN ARCTIC AIR
MASS MOVING INTO THE NORTHERN PLAINS FROM CANADA. THE ARCTIC AIR
IS FORECAST TO PLUNGE SOUTH AND EASTWARD AND OVERSPREAD THE
EASTERN THIRD OF THE COUNTRY IN THE NEXT COUPLE OF DAYS.  WITH A
CONTINENTAL ORIGIN...MOISTURE ASSOCIATED WITH THE COLD FRONT IS
SCARCE AS ONLY LIGHT SNOW IS EXPECTED TO MOVE ACROSS THE GREAT
LAKES.

MEANWHILE...AN UPPER-LEVEL DISTURBANCE IS MOVING EASTWARD INTO THE
CENTRAL PLAINS...TRIGGERING THE FORMATION OF A SURFACE COLD FRONT.
SOUTHERLY FLOW AHEAD OF THE FRONT IS EXPECTED TO DRAW SOME GULF
MOISTURE NORTHWARD INTO THE DEEP SOUTH AS THE ENTIRE SYSTEM MOVES
QUICKLY EASTWARD TOWARDS THE SOUTHEASTERN U.S. ON FRIDAY. SHOWERS
AND THUNDERSTORMS ARE EXPECTED TO SPREAD ACROSS THE REGION THROUGH
FRIDAY.

BY FRIDAY NIGHT INTO SATURDAY...BOTH THE ARCTIC AIR MASS AND THE
UPPER-LEVEL DISTURBANCE IN THE SOUTH WILL WORK IN CONCERT TO
TRIGGER THE FORMATION OF A LARGE CYCLONE JUST OFF THE EAST COAST
OF THE U.S.  AS THE ARCTIC COLD FRONT BEGINS TO MOVE INTO THE
EASTERN SEABOARD AND THE STORM BEGINS TO STRENGTHEN
OFFSHORE...LIGHT SNOW OR RAIN MAY BE ENHANCED FOR A PERIOD OF TIME
ESPECIALLY NEAR THE SOUTHERN NEW ENGLAND COAST EARLY ON SATURDAY.

OVER THE PACIFIC NORTHWEST...A SERIES OF PACIFIC FRONTS AND
WEAKENING LOW PRESSURE SYSTEMS ARE EXPECTED TO KEEP A GOOD CHANCE
OF PRECIPITATION OVER THE NEXT FEW DAYS. ELSEWHERE...SCATTERED
SHOWERS AND THUNDERSTORMS ARE EXPECTED NEAR THE EAST COAST OF
FLORIDA AS WELL AS THE KEYS IN THE NEXT COUPLE OF DAYS.

KONG


GRAPHICS AVAILABLE AT WWW.HPC.NCEP.NOAA.GOV



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