443  
FXUS02 KWBC 301901  
PMDEPD  
 
EXTENDED FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
300 PM EDT SAT JUL 30 2022  
 
VALID 12Z TUE AUG 02 2022 - 12Z SAT AUG 06 2022  
   
..HEAT WAVE TO SPREAD FROM THE PLAINS TO THE EAST NEXT WEEK
 
 
...WET MONSOONAL PATTERN CONTINUES FOR THE SOUTHWEST AND GREAT  
BASIN...  
 
   
..GENERAL OVERVIEW
 
 
A WELCOMED PATTERN CHANGE IS FORECAST FOR THE NORTHWESTERN U.S.  
NEXT WEEK AS UPPER LEVEL TROUGHING AND ASSOCIATED COLD FRONT  
HERALD AN EVENTUAL RETURN TO MUCH MORE PLEASANT TEMPERATURES. THE  
PEAK SUMMER UPPER RIDGE WILL IN TURN SPREAD DOWNSTREAM TO  
ENCOMPASS MUCH OF THE CENTRAL AND EASTERN U.S. WITH WIDESPREAD HOT  
AND HUMID WEATHER. LESS ORGANIZED AREAS OF EXCESSIVE RAINFALL WILL  
BECOME THE NORM ACROSS MUCH OF THIS BROAD REGION THAN HAS BEEN  
CASE RECENTLY, BUT EXPECT LINGERING MONSOONAL FLOW UP ACROSS THE  
SOUTHWEST AND GREAT BASIN/ROCKIES.  
 
   
..GUIDANCE EVALUATION/PREDICTABILITY ASSESSMENT
 
 
WHILE A GENERAL MODEL AND ENSEMBLE COMPOSITE BLEND SEEMS  
REASONABLE FOR DAY 3/TUESDAY, THE WPC MEDIUM RANGE PRODUCT SUITE  
WAS PRIMARILY DERIVED FROM A COMBINATION OF THE 13 UTC NATIONAL  
BLEND OF MODELS AND THE 06 UTC GEFS AND 00 UTC ECMWF ENSEMBLE MEAN  
DAYS 4-7 (WEDNESDAY-NEXT SATURDAY). THIS MAINTAINS REASONABLE WPC  
PRODUCT CONTINUITY OVERALL, BUT WITH A FORECAST THAT IS ON THE  
SLOW SIDE OF THE FULL ENVELOPE OF GUIDANCE SOLUTIONS THAT LIMITS  
THE BULK OF EASTERN PACIFIC UPPER TROUGH HEIGHT FALLS INTO THE  
NORTHWEST TUESDAY/WEDNESDAY MORE THAN THE PRIOR FORECAST. THIS  
SEEMS MORE REASONABLE AS THE OFFSHORE CLOSED SYSTEM IS POSITIONED  
BETWEEN HIGHLY AMPLIFIED UPSTREAM AND DOWNSTREAM AMPLIFIED UPPER  
RIDGES. LATEST 12 UTC MODEL TRENDS ARE NOW EVEN MORE IN FAVOR OF  
HOLDING EASTERN PACIFIC UPPER TROUGH ENERGIES OFFSHORE, INSTEAD  
WAITING FOR APPROACH OF MORE NORTHERN STREAM ENERGIES FROM THE  
GULF OF ALASKA BY THURSDAY.  
 
   
..WEATHER/HAZARDS HIGHLIGHTS
 
 
ANOTHER HEAT WAVE IS EXPECTED TO MAKE WEATHER HEADLINES ON TUESDAY  
ACROSS THE NORTHERN PLAINS AND UPPER MIDWEST FOR TUESDAY AND  
WEDNESDAY, WITH HIGHS RUNNING ON THE ORDER OF 15-20 DEGREES ABOVE  
AVERAGE, POTENTIALLY SETTING SOME DAILY RECORDS. THE HEAT THEN  
REACHES THE GREAT LAKES, OHIO VALLEY, AND THEN THE EAST COAST FOR  
LATER IN THE WEEK AS THE MONTH OF AUGUST BEGINS HOT AND HUMID.  
HEAT INDICES MAY EXCEED 105 DEGREES FOR SOME AREAS. MEANWHILE,  
TEMPERATURES WILL LIKELY SLOWLY REVERT TO BE NEAR TO SLIGHTLY  
BELOW NORMAL ACROSS MUCH OF THE WESTERN U.S., WITH THE COOLEST  
READINGS OVER WASHINGTON AND OREGON.  
 
IN TERMS OF PRECIPITATION, THERE WILL LIKELY BE SOME ABATEMENT IN  
THE COVERAGE OF HEAVY RAINFALL ACROSS MUCH OF THE NATION WITH NO  
SLIGHT RISK AREAS OF EXCESSIVE RAINFALL FOR TUESDAY AND WEDNESDAY.  
THERE WILL STILL BE PLENTY OF MONSOONAL MOISTURE IN PLACE ACROSS  
THE SOUTHWESTERN U.S., BUT NOT TO THE EXTENT THAT HAS BEEN  
OBSERVED RECENTLY. HOWEVER, THIS MAY INCREASE AGAIN GOING INTO  
FRIDAY AND NEXT SATURDAY WITH A GREATER COVERAGE OF SHOWERS AND  
STORMS. THERE MAY ALSO BE A ROUND OF HEAVY SHOWERS AND STRONG  
THUNDERSTORMS ACROSS PORTIONS OF THE GREAT LAKES AND THE NORTHEAST  
AHEAD OF A COLD FRONT TOWARDS THE END OF THE WEEK AS INSTABILITY  
GROWS IN ADVANCE OF NORTHERN STREAM UPPER ENERGIES.  
 
HAMRICK/SCHICHTEL  
 
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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