120 
FXUS01 KWBC 232009
PMDSPD
 
SHORT RANGE FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
308 PM EST MON NOV 23 2009
 
VALID 00Z TUE NOV 24 2009 - 12Z WED NOV 25 2009
 
A SHOWERY PATTERN IS SHAPING UP ACROSS THE U.S. THIS WEEK. THREE
SEPARATE FRONTAL SYSTEMS ARE WREAKING HAVOC ON THE PACIFIC
NORTHWEST...CENTRAL PLAINS AND UPPER MISSISSIPPI VALLEY...AND THE
NORTH AND CENTRAL ATLANTIC COAST. STRONG MID AND UPPER-LEVEL
ENERGY PROVIDE THE DRIVING FORCE FOR THIS THANKSGIVING WEEK'S
WEATHER.

AN OCCLUDED SYSTEM IS MAKING ITS WAY INLAND ALONG THE CANADIAN
PACIFIC COAST. AS THE DAY PROGRESSES THE FRONT WILL DROP SOUTH AND
EASTWARD AHEAD OF HIGH PRESSURE BUILDING INTO SOUTHWESTERN
CANADA...PUSHING SNOW SHOWERS INTO THE NORTHERN ROCKIES.
PRECIPITATION WILL REMAIN SHOWERY IN NATURE...WITH SOME HEAVIER
SNOW OCCURRING IN THE HIGHEST ELEVATIONS. THE STRONG DOME OF HIGH
PRESSURE SITUATED OVER THE DESERT SOUTH WEST WILL ENSURE THAT THE
PRECIPITATION ASSOCIATED WITH THIS PACIFIC SYSTEM STAYS TO THE
NORTH...LEAVING THE SKY CLEAR OVER THE SOUTHWESTERN U.S. 

MEANWHILE...THE MIDDLE OF THE COUNTRY WILL RECEIVE THE HIGHEST
PRECIPITATION AMOUNTS THIS WEEK. A COLD FRONT...CURRENTLY
STRETCHED FROM MINNESOTA SOUTH SOUTHWESTWARD INTO NEW MEXICO...IS
EXPECTED TO MOVE SLOWLY TO THE EAST. OVERNIGHT TONIGHT AN INCREASE
IN MID-LEVEL ENERGY WILL CAUSE THE SOUTHERN PORTION OF THE FRONT
TO INTENSIFY...BRINGING MODERATE RAIN TO THE MIDDLE MISSISSIPPI
VALLEY. AS THE LOW PRESSURE IN THIS AREA CONTINUES TO
DEEPEN...WIND SPEEDS WILL INCREASE AND THE SWATH OF PRECIPITATION
WILL EXPAND. BY THURSDAY SCATTERED PRECIPITATION CAN BE EXPECTED
ACROSS MUCH OF THE EASTERN HALF OF THE COUNTRY.

COLLINS
 

GRAPHIC AVAILABLE AT WWW.HPC.NCEP.NOAA.GOV
$$