320  
FXUS01 KWBC 042000  
PMDSPD  
 
SHORT RANGE FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
300 PM EST SUN FEB 04 2018  
 
VALID 00Z MON FEB 05 2018 - 00Z WED FEB 07 2018  
 
...WINTER WEATHER THREATS TO IMPACT AREAS OF THE NORTHEASTERN U.S.  
AS WELL AS THE NATION'S MID-SECTION...  
 
...HEAVY SNOW LIKELY TO FALL OVER THE UPPER INTERMOUNTAIN WEST AND  
INTO THE NORTHERN/CENTRAL ROCKIES...  
 
...MILD TEMPERATURES CONTINUE OVER THE WESTERN STATES WHILE FRIGID  
WEATHER REMAINS EAST OF THE ROCKIES...  
 
THE UPPER PATTERN ACROSS THE NATION WILL CHANGE VERY LITTLE DURING  
THE NEXT COUPLE OF DAYS AS A BROAD TROUGH EXTENDS FROM THE  
INTERMOUNTAIN WEST ALL THE WAY TO THE EAST COAST. IN ADDITION TO  
THE BELOW AVERAGE TEMPERATURES THIS PATTERN WILL FEATURE, THERE  
SHOULD ALSO BE A PAIR OF WINTRY PRECIPITATION THREATS DURING THE  
PERIOD. THE INITIAL AREA OF INTEREST STRETCHES FROM THE  
MID-ATLANTIC INTO INTERIOR NEW ENGLAND WHERE A BROAD AREA OF  
WINTER WEATHER ADVISORIES ARE IN EFFECT. FORECAST AMOUNTS REMAIN  
ON THE MODEST SIDE WITH 4 TO 8 INCHES OF SNOW EXPECTED ACROSS  
NORTHERN SECTIONS OF VERMONT, NEW HAMPSHIRE, AND MAINE WHILE LIGHT  
ICE ACCUMULATIONS ARE POSSIBLE FROM SOUTHEASTERN NEW YORK DOWN  
INTO EXTREME NORTHERN MARYLAND. A GRADUAL SHIFT TO A COLD RAIN IS  
FORECAST ACROSS THESE LATTER LOCATIONS AS THE GROUND TEMPERATURES  
CONTINUE TO RISE ABOVE FREEZING. THE ADDITIONAL WINTRY  
PRECIPITATION THREATS LOOMS WITH THE NEXT SYSTEM SWEEPING THROUGH  
THE CENTER OF THE COUNTRY. WITH PLENTY OF COLD AIR ALREADY IN  
PLACE, LIGHT/MODERATE SHOULD SPREAD OVER THE CENTRAL PLAINS AND  
MIDDLE MISSISSIPPI VALLEY WITH GENERAL AMOUNTS IN THE 4 TO 6 INCH  
RANGE. FARTHER SOUTH, AS MILDER AIR OVERRIDES THE MODIFIED ARCTIC  
AIRMASS AT THE SURFACE, A BAND OF FREEZING RAIN SHOULD IMPACT AN  
AREA OF SOUTHWESTERN OKLAHOMA UP INTO SOUTHERN MISSOURI.  
 
A CONVEYOR BELT OF DISTURBANCES ARE FORECAST TO SWEEP THROUGH THE  
PACIFIC NORTHWEST AND INTO THE ROCKY MOUNTAIN REGION. AS THESE  
IMPULSES TRACK ATOP A STALLED ARCTIC BOUNDARY GENERALLY STUCK  
CLOSE TO THE TERRAIN, ABUNDANT PRECIPITATION WILL BREAK OUT,  
PARTICULARLY OVER REGIONS OF LOCAL UPSLOPE FLOW. SNOW LEVELS  
SHOULD BE APPRECIABLY LOW ENOUGH TO BRING ACCUMULATING SNOWS DOWN  
INTO MANY OF THE VALLEY LOCALES. A COUPLE FEET OF SNOW IS LIKELY  
TO FALL ACROSS THE BITTERROOTS, SAWTOOTH, TETONS, AND INTO THE  
BIGHORNS. WHILE NOT QUITE AS HEAVY, EXPECT ANYWHERE FROM 12 TO 18  
INCHES TO FALL OVER THE WASHINGTON CASCADES AS WELL AS THE  
COLORADO ROCKIES.  
 
WITH A STRONG UPPER RIDGE ANCHORING THE FAR EASTERN PACIFIC AND  
INTO THE IMMEDIATE WEST COAST, TEMPERATURES WILL REMAIN WELL ABOVE  
AVERAGE FOR EARLY FEBRUARY. DEPARTURES FROM CLIMATOLOGY WILL  
LIKELY BE IN THE 10 TO 15 DEGREE RANGE WITH 50S COMMONPLACE ACROSS  
THE PACIFIC NORTHWEST, 50S AND 60S OVER AREAS OF THE CENTRAL GREAT  
BASIN, AND EVEN SOME LOWER 80S POSSIBLE IN THE DESERT SOUTHWEST.  
SOME DAILY TEMPERATURE RECORDS MAY BE BROKEN GIVEN THE VERY MILD  
OVERNIGHT TEMPERATURES EXPECTED. WHILE THE WESTERN STATES BASK IN  
THE PERSISTENT WARMTH, IT WILL BE QUITE THE OPPOSITE STORY EAST OF  
THE ROCKY MOUNTAINS.  
 
RUBIN-OSTER  
 
GRAPHICS AVAILABLE AT  
WWW.WPC.NCEP.NOAA.GOV/BASICWX/BASICWX_NDFD.PHP  

 
 
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