251  
FXUS02 KWBC 251840  
PMDEPD  
 
EXTENDED FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
139 PM EST FRI FEB 25 2022  
 
VALID 12Z MON FEB 28 2022 - 12Z FRI MAR 04 2022  
   
..OVERVIEW
 
 
MOST GUIDANCE EXPECTS FLOW ACROSS THE LOWER 48 TO HAVE MODERATE  
AMPLITUDE NEXT MONDAY-FRIDAY. A GENERAL WESTERN RIDGE/BROAD  
EASTERN MEAN TROUGH PATTERN THROUGH AT LEAST MIDWEEK SHOULD  
PROGRESS EASTWARD THEREAFTER AS A PACIFIC TROUGH MOVES INTO THE  
WESTERN U.S. MOISTURE AHEAD OF THE PACIFIC TROUGH WILL LIKELY  
BRING MEANINGFUL PRECIPITATION INTO THE PACIFIC NORTHWEST WITH  
SOMEWHAT LIGHTER AMOUNTS EVENTUALLY SPREADING ACROSS OTHER PARTS  
OF THE WEST. MANY AREAS EAST OF THE ROCKIES WILL BE FAIRLY DRY,  
WITH ANY PRECIPITATION GENERALLY LIGHT AND CONFINED TO NORTHERN  
AREAS WITH ONE OR MORE WAVES AND POSSIBLY SOUTHERN PARTS OF THE  
PLAINS MID-LATE WEEK. NEAR TO ABOVE NORMAL TEMPERATURES WILL BE  
MOST COMMON NEXT WEEK. BEST POTENTIAL FOR BELOW NORMAL READINGS  
WILL BE OVER/NEAR THE SOUTHERN PLAINS EARLY IN THE WEEK AND IN  
NORTHERN PARTS OF THE EASTERN U.S. ON SOME DAYS.  
   
..GUIDANCE EVALUATION/PREDICTABILITY ASSESSMENT
 
 
MODEL BLENDS CONSISTING OF DETERMINISTIC GUIDANCE FROM DAYS 3-5  
THEN ENSEMBLE MEANS ON DAYS 6 & 7 PROVIDED A REASONABLE SOLUTION  
FOR THE MEDIUM RANGE. FOR MONDAY, A GREATER WEIGHTING WAS GIVEN TO  
THE 00Z EC/CMC DUE TO THE UNCERTAINTY AROUND AN IMPULSE MOVING  
THROUGH THE WEST. THE GFS AMPLIFIED THIS SHORTWAVE INTO A CLOSED  
LOW AND HAD IT MOVE AT A SLOW PACE COMPARED TO THE REST OF THE  
DETERMINISTIC SUITE SO IT WAS EXCLUDED FROM TUESDAY'S BLEND. THE  
00Z UK AND CMC JOIN THE 06Z GFS IN LOSING WEIGHTING ON WEDNESDAY,  
DUE TO DIFFICULTIES AND SPREAD IN HANDLING A TROUGH APPROACHING  
THE PACIFIC NORTHWEST. THEREFORE, A BLEND OF 00Z EC AND THE  
ENSEMBLE MEANS WERE UTILIZED THROUGH THURSDAY. THE EC WAS DROPPED  
AND A FULL ENSEMBLE BLEND WAS USED BY FRIDAY.  
   
..WEATHER HIGHLIGHTS/THREATS
 
 
EXPECT THE HEAVIEST PRECIPITATION NEXT WEEK TO BE OVER THE PACIFIC  
NORTHWEST AND NORTHERN ROCKIES. A SERIES OF SYSTEMS EMBEDDED IN  
MOIST FLOW AHEAD OF AN INITIALLY SLOW-MOVING EASTERN PACIFIC UPPER  
TROUGH MAY PRODUCE AN ATMOSPHERIC RIVER EVENT OVER THESE REGIONS  
EARLY-MID WEEK. EVENTUAL PROGRESSION OF THE UPPER TROUGH SHOULD  
BRING A LIGHTER TREND TO THE NORTHWEST AND SPREAD PRECIPITATION  
FARTHER SOUTH AND EAST LATER IN THE WEEK. EXACTLY HOW FAR SOUTH  
THE MOISTURE REACHES INTO CALIFORNIA AND THE GREAT BASIN/ROCKIES  
WILL DEPEND ON THE AMPLITUDE OF THE UPPER TROUGH. FARTHER EAST, A  
COUPLE CLIPPER SYSTEMS MAY BRING MOSTLY LIGHT SNOW FROM THE UPPER  
MIDWEST THROUGH THE GREAT LAKES AND NORTHEAST. ADDITIONAL  
NORTHERN TIER SNOW WILL BE POSSIBLE LATE IN THE WEEK AHEAD OF LOW  
PRESSURE ORGANIZING OVER THE NORTH-CENTRAL PLAINS. A WEAK  
SHORTWAVE CROSSING THE SOUTHEAST MONDAY MAY PRODUCE SOME LIGHT  
RAIN BEFORE DEPARTING. ANOTHER WEAK UPPER FEATURE MAY GENERATE  
LIGHT/SCATTERED RAIN OVER THE SOUTHERN PLAINS AROUND MID-LATE WEEK.  
 
ASIDE FROM CHILLY MORNING LOWS OVER THE SOUTHERN PLAINS ON MONDAY  
(UP TO 10-15F BELOW NORMAL), THE FORECAST PATTERN WILL SUPPORT  
ABOVE NORMAL TEMPERATURES OVER A MAJORITY OF THE WESTERN AND  
CENTRAL U.S. MONDAY-WEDNESDAY FOLLOWED BY A COOLING TREND OVER THE  
WEST AND A WARMER TREND OVER THE EAST. PLUS 10-20F ANOMALIES WILL  
BE POSSIBLE FOR MAX AND/OR MIN TEMPERATURES FOR ONE OR MORE DAYS  
OVER THE GREAT BASIN/SOUTHWEST AND PARTS OF THE ROCKIES/PLAINS.  
AREAS FROM THE UPPER MIDWEST TO THE NORTHEAST WILL TEND TO STAY  
BELOW NORMAL THOUGH, WITH SOME LOCATIONS IN THE NORTHEAST 10-20F  
BELOW NORMAL EARLY IN THE WEEK.  
 
KEBEDE/RAUSCH  
 
ADDITIONAL 3-7 DAY HAZARD INFORMATION CAN BE FOUND ON THE WPC  
MEDIUM RANGE HAZARDS OUTLOOK CHART AT:  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/THREATS/THREATS.PHP  
 
WPC MEDIUM RANGE 500MB HEIGHTS, SURFACE SYSTEMS, WEATHER GRIDS,  
QUANTITATIVE PRECIPITATION, WINTER WEATHER OUTLOOK PROBABILITIES  
AND HEAT INDICES ARE AT:  
 
HTTPS://WWW.WPC.NCEP.NOAA.GOV/MEDR/5DAYFCST500_WBG.GIF  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/MEDR/5DAYFCST_WBG_CONUS.GIF  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/5KM_GRIDS/5KM_GRIDSBODY.HTML  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/QPF/DAY4-7.SHTML  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/WWD/PWPF_D47/PWPF_MEDR.PHP?DAY=4  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/HEAT_INDEX.SHTML  
 

 
 

 
 
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