856  
FXUS02 KWBC 310658  
PMDEPD  
 
EXTENDED FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
257 AM EDT SUN JUL 31 2022  
 
VALID 12Z WED AUG 3 2022 - 12Z SUN AUG 7 2022  
 
...HEAT WAVE TO SPREAD FROM THE PLAINS TO THE EAST COAST NEXT  
WEEK...  
 
...WET MONSOONAL PATTERN CONTINUES FOR THE SOUTHWEST AND GREAT  
BASIN...  
 
   
..GENERAL OVERVIEW
 
 
A ACTIVE UPPER LEVEL FLOW PATTERN WILL BE IN PLACE ACROSS THE  
NORTHERN TIER STATES, WITH A WELL DEFINED TROUGH AND COLD FRONT  
CROSSING THE GREAT LAKES AND THEN NEW ENGLAND BY THE END OF THE  
WEEK. ANOTHER TROUGH IS EXPECTED TO REACH THE NORTHERN ROCKIES BY  
FRIDAY AND THEN TRAVERSE THE NORTHERN PLAINS BY NEXT WEEKEND.  
MEANWHILE, THE CORE OF THE UPPER RIDGE INTENSIFIES ACROSS THE  
CENTRAL PLAINS FOR THE END OF THE WEEK AND EXPANDS IN COVERAGE BY  
THE WEEKEND, AND THE MONSOONAL PATTERN ACROSS THE FOUR CORNERS  
REGION LOOKS TO REMAIN ACTIVE AS WELL.  
 
   
..GUIDANCE EVALUATION/PREDICTABILITY ASSESSMENT
 
 
THE 00Z MODEL GUIDANCE SUITE IS IN VERY GOOD OVERALL SYNOPTIC  
SCALE AGREEMENT ACROSS THE CONTINENTAL U.S. ON WEDNESDAY, AND  
OVERALL FORECAST CONFIDENCE THROUGH THE END OF THE WEEK IS  
IMPROVED COMPARED TO THE PAST TWO DAYS. THE LINGERING UPPER LOW  
WELL OFF THE PACIFIC COAST HAS BEEN ONE OF THE WILD CARDS IN THE  
PATTERN EVOLUTION, BUT THERE APPEARS TO BE ENOUGH SEPARATION  
BETWEEN IT AND THE NORTHERN STREAM TROUGH TO REDUCE OVERALL MODEL  
SPREAD. BY NEXT WEEKEND, MORE SUBSTANTIAL DIFFERENCES ARE  
APPARENT ACROSS SOUTHERN CANADA AND THE NORTHERN TIER STATES, WITH  
THE 00Z CMC APPEARING TO BE MOST AT ODDS WITH THE ENSEMBLE MEAN  
SOLUTIONS. THE WPC FORECAST WAS DERIVED FROM A  
CMC/GFS/ECMWF/UKMET BLEND AS A STARTING POINT FOR WEDNESDAY, AND  
THEN GRADUALLY INCREASED PERCENTAGES OF THE ECENS AND GEFS MEANS  
WHILE STILL MAINTAINING SOME GFS/ECMWF AND SLIGHTLY LESS OF THE  
12Z CMC.  
 
   
..WEATHER/HAZARDS HIGHLIGHTS
 
 
ANOTHER HEAT WAVE IS EXPECTED TO MAKE WEATHER HEADLINES FOR THE  
SECOND HALF OF THE WEEK FROM THE MIDWEST TO THE NORTHEAST U.S.,  
WITH DAYTIME HIGHS RUNNING WELL INTO THE 90S AND EXCEEDING 100  
DEGREES IN SOME CASES. MEANWHILE, TEMPERATURES WILL LIKELY BE  
NEAR TO SLIGHTLY BELOW NORMAL ACROSS MUCH OF THE WESTERN U.S. FOR  
MOST OF THE FORECAST PERIOD. THIS ALSO INCLUDES THE DESERT  
SOUTHWEST WHERE INCREASED CLOUD COVER AND RAINFALL WILL KEEP  
TEMPERATURES IN CHECK.  
 
IN TERMS OF PRECIPITATION, THERE IS A STRONGER MODEL SIGNAL FOR A  
CORRIDOR OF HEAVY SHOWERS AND STORMS AHEAD OF THE COLD FRONT  
CROSSING THE GREAT LAKES AND OHIO VALLEY, AND A SLIGHT RISK AREA  
OF EXCESSIVE RAINFALL HAS BEEN ADDED TO THE DAY 4 OUTLOOK FROM  
NORTHERN ILLINOIS TO SOUTHERN MICHIGAN. THERE WILL STILL BE  
PLENTY OF MONSOONAL MOISTURE IN PLACE ACROSS THE SOUTHWESTERN  
U.S., WITH ENOUGH EXPECTED COVERAGE OF SLOW MOVING STORMS TO MERIT  
A SLIGHT RISK ON DAY 5 ACROSS MUCH OF SOUTHEASTERN ARIZONA.  
SCATTERED TO NUMEROUS SHOWERS AND STORMS ARE ALSO LIKELY FOR  
PORTIONS OF THE GULF COAST REGION TO CLOSE OUT THE WEEK.  
 
HAMRICK  
 
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, EXPERIMENTAL EXCESSIVE RAINFALL  
OUTLOOK, 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/#PAGE=ERO  
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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