014  
FXUS02 KWBC 250658  
PMDEPD  
 
EXTENDED FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
158 AM 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
 
 
MODELS AND ENSEMBLE MEANS OFFER SIMILAR IDEAS FOR THE OVERALL  
PATTERN EVOLUTION THROUGH THE PERIOD BUT THERE ARE SOME EMBEDDED  
UNCERTAINTIES. SOLUTIONS ARE SIMILAR FOR A LEADING WAVE TRACKING  
FROM THE NORTHERN PLAINS THROUGH THE GREAT LAKES MONDAY-TUESDAY  
BUT THERE HAS BEEN GREATER SPREAD AND RUN-TO-RUN VARIABILITY FOR  
THE PATTERN BEHIND IT, DUE TO DIFFERENCES IN THE HANDLING OF  
CENTRAL-SOUTHERN CANADA SHORTWAVE ENERGY. FASTER PROGRESSION OF  
THE ENERGY LEADS TO MORE MIDWEST/EASTERN U.S. HIGH PRESSURE BY  
WEDNESDAY-THURSDAY WHILE SLOWER PROGRESSION ALLOWS FOR A MORE  
DEFINED SURFACE WAVE AND FARTHER NORTH FRONT. THE PREFERRED  
STARTING POINT OF A 12Z/18Z MODEL COMPOSITE TRANSITIONING TO A  
MODEL/ENSEMBLE MEAN BLEND MID-LATE PERIOD INTRODUCED A HINT OF  
SUCH A SURFACE WAVE. NEW 00Z RUNS SUPPORT EXISTENCE OF THIS  
SECOND WAVE BUT WITH A DECENT AMOUNT OF SPREAD. THE OTHER  
LARGE-SCALE CONSIDERATION IS THE AMPLITUDE AND TIMING OF THE UPPER  
TROUGH MOVING INTO THE WEST. GFS RUNS HAVE TENDED TO BE ON THE  
FLATTER/FASTER SIDE OF THE SPECTRUM. THE 18Z RUN WAS CLOSER TO  
OTHER MODELS AND MEANS (INCLUDING THE GEFS) THAN THE 12Z OR NEW  
00Z RUNS. THE NEW 00Z ECMWF HAS TRENDED A LITTLE WEAKER/FASTER  
THOUGH. A NUMBER OF MODEL RUNS ARE SUGGESTING THAT A TRAILING  
SMALL-SCALE/LOW-PREDICTABILITY FEATURE MAY DROP INTO THE MEAN  
TROUGH TOWARD FRIDAY AND THIS WOULD ADD SOME COMPLEXITY TO THE  
FORECAST. AN INTERMEDIATE DEPICTION OF THIS TROUGH LOOKS  
REASONABLE AT THIS TIME. THERE WILL ALSO BE A COUPLE SOUTHERN  
TIER FEATURES WITH RELATIVELY LOW PREDICTABILITY FOR SPECIFICS, A  
WEAK SHORTWAVE CROSSING THE SOUTHEAST EARLY IN THE WEEK AND ENERGY  
THAT COULD BRIEFLY CLOSE OFF A LOW OVER/NEAR ARIZONA BEFORE  
SHEARING EASTWARD.  
   
..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 FOCUS PERIODS OF LOCALLY MODERATE TO HEAVY RAIN AND  
HIGHER ELEVATION SNOW 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.  
 
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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