082  
FXUS02 KWBC 271951  
PMDEPD  
 
EXTENDED FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
350 PM EDT WED JUL 27 2022  
 
VALID 12Z SAT JUL 30 2022 - 12Z WED AUG 03 2022  
 
...DANGEROUS HEAT WAVE PERSISTS OVER THE NORTHWEST/GREAT BASIN  
THROUGH THE WEEKEND BEFORE THE ANOMALOUS HEAT SHIFTS EAST ACROSS  
THE NORTH-CENTRAL U.S. NEXT WEEK...  
 
...HEAVY TO EXCESSIVE RAIN THREAT FOR THE SOUTH-CENTRAL PLAINS TO  
THE SOUTHERN MID-ATLANTIC SUNDAY INTO MONDAY, WITH A LINGERING  
MONSOON IN THE SOUTHWEST THROUGH NEXT WEEK...  
 
   
..OVERVIEW
 
 
A DANGEROUS HEAT WAVE WILL CONTINUE THROUGH THIS WEEKEND ACROSS  
THE NORTHWEST BEFORE THE HEAT SHIFTS EAST ACROSS THE NORTH-CENTRAL  
STATES NEXT WEEK AHEAD OF AN UPPER TROUGH MOVING INTO THE PACIFIC  
NORTHWEST. UPPER RIDGING AND HEAT/HUMIDITY WILL ALSO LINGER OVER  
THE SOUTHERN PLAINS AND LOWER MISSISSIPPI VALLEY TO THE SOUTH OF A  
WAVY QUASI-STATIONARY FRONT. THIS FRONT WILL REMAIN A FOCUS FOR  
MULTI-DAY HEAVY RAIN THREATS FROM THE SOUTH-CENTRAL PLAINS TO THE  
SOUTHERN MID-ATLANTIC WITH EXCESSIVE RAINFALL LIKELY SATURDAY  
NIGHT INTO MONDAY. RENEWED TROUGHING WILL TAKE SHAPE ACROSS THE  
GREAT LAKES AND NORTHEAST INTO NEXT WEEK, WHILE A SEEMINGLY NEVER  
ENDING STREAM OF MONSOONAL MOISTURE CONTINUES TO FLOW INTO THE  
SOUTHWEST AND SOUTHERN ROCKIES.  
 
   
..GUIDANCE EVALUATION/PREDICTABILITY ASSESSMENT
 
 
THE LATEST GLOBAL DETERMINISTIC MODELS REMAIN WELL CLUSTERED WITH  
THE LARGE-SCALE PATTERN AND EVOLUTION OF THE EXPANSIVE  
WESTERN/SOUTHERN U.S. RIDGE AND THE TROUGH DIGGING INTO THE  
NORTHEAST THIS WEEKEND AND ITS EASTWARD SHIFT EARLY NEXT WEEK.  
EVEN DIFFERENCES IN THE WEAKER SHORTWAVES MOVING THROUGH THE GREAT  
LAKES ARE MINOR. OUT WEST, THERE ARE LINGERING QUESTIONS IN THE  
TIMING AND STRENGTH OF A SHORTWAVE TROUGH ENTERING THE NORTHWEST  
WITH THE 06Z/12Z GFS MORE PROGRESSIVE AND THE 00Z/12Z UKMET JUST  
BEHIND IN BRINGING THIS ENERGY ONSHORE, WHILE THE GEFS ENSEMBLE  
MEANS SUPPORT A SLOWER SOLUTION AND CLOSER TO THE 00Z ECMWF/CMC.  
THE RESULT OF THE MORE PROGRESSIVE GFS IS A FLATTER PATTERN OVER  
THE NORTHERN TIER AND PREFERENCES WAS AGAIN GIVEN TO THE ECMWF/CMC  
LATER IN THE BLEND (ALONG WITH THE GEFS/ECENS). THIS RESULTS IN AN  
OVERALL MORE AMPLIFIED PATTERN OVER THE CONUS BY THE MIDDLE OF  
NEXT WEEK WITH TROUGHING OVER THE WEST AND EAST AROUND A BUILDING  
HEAT DOME OVER THE FOUR CORNERS AND INTO THE PLAINS.  
 
   
..WEATHER/HAZARDS HIGHLIGHTS
 
 
THE HEAT WAVE CONTINUES THROUGH SUNDAY FOR THE NORTHWEST/GREAT  
BASIN. RELIEF COMES IN THE FORM OF AN UPPER TROUGH AROUND SUNDAY  
NIGHT, THOUGH THIS SHIFTS THE ANOMALOUS HEAT EAST ACROSS THE  
NORTHERN PLAINS THROUGH THE FIRST HALF OF NEXT WEEK. ABOVE NORMAL  
TEMPERATURES CONTINUE FOR THE SOUTHERN PLAINS AND SOUTHEAST  
THROUGH THE NEXT WEEK.  
 
A QUASI-STATIONARY BOUNDARY DRAPED FROM THE SOUTH-CENTRAL PLAINS  
TO THE SOUTHERN MID-ATLANTIC WILL CONTINUE TO FOCUS A THREAT FOR  
HEAVY TO EXCESSIVE RAINFALL SATURDAY NIGHT INTO MONDAY WITH LIKELY  
REPEATED ROUNDS OF HEAVY RAINFALL INCREASING THE RISK FOR  
LOCALIZED FLASH FLOODING. THE DAYS 4 AND 5 EXPERIMENTAL EROS  
CONTINUE TO HAVE HAVE EXPANSIVE SLIGHT RISKS DEPICTED ALONG THIS  
BOUNDARY FROM THE CENTRAL PLAINS, ACROSS THE TN VALLEY/SOUTHERN  
APPALACHIANS AND THE SOUTHERN MID-ATLANTIC. MEANWHILE, PERSISTENT  
MONSOONAL MOISTURE WILL CONTINUE TO SUPPORT DIURNALLY FAVORED  
SHOWERS/STORMS WITH LOCALLY HEAVY TO EXCESSIVE RAINFALL OVER AN  
ALREADY VERY SOGGY FOUR CORNERS AND SOUTHERN ROCKIES REGION  
THROUGH NEXT WEEK.  
 
JACKSON  
 
HAZARDS:  
- HEAVY RAIN ACROSS PORTIONS OF THE CENTRAL PLAINS, THE CENTRAL  
ROCKIES, THE LOWER MISSISSIPPI  
VALLEY, THE CENTRAL GREAT BASIN, THE TENNESSEE VALLEY, THE  
SOUTHERN ROCKIES, THE MIDDLE MISSISSIPPI  
VALLEY, THE MID-ATLANTIC, THE SOUTHERN APPALACHIANS, THE  
SOUTHEAST, THE SOUTHERN PLAINS, THE OHIO  
VALLEY, AND THE SOUTHWEST, SAT, JUL 30.  
- HEAVY RAIN ACROSS PORTIONS OF THE SOUTHERN ROCKIES AND THE  
SOUTHWEST, SAT-WED, JUL 30-AUG 3.  
- HEAVY RAIN ACROSS PORTIONS OF THE LOWER MISSISSIPPI VALLEY, THE  
CENTRAL APPALACHIANS, THE  
TENNESSEE VALLEY, THE MIDDLE MISSISSIPPI VALLEY, THE MID-ATLANTIC,  
THE SOUTHERN APPALACHIANS, THE  
SOUTHEAST, AND THE OHIO VALLEY, SUN-MON, JUL 31-AUG 1.  
- FLOODING POSSIBLE ACROSS PORTIONS OF THE SOUTHERN APPALACHIANS,  
THE MID-ATLANTIC, THE CENTRAL  
APPALACHIANS, THE OHIO VALLEY, AND THE TENNESSEE VALLEY.  
- FLOODING OCCURRING OR IMMINENT ACROSS PORTIONS OF THE MIDDLE  
MISSISSIPPI VALLEY AND THE NORTHERN  
PLAINS.  
- FLOODING LIKELY ACROSS PORTIONS OF THE MIDDLE MISSISSIPPI VALLEY.  
- EXCESSIVE HEAT ACROSS PORTIONS OF CALIFORNIA, THE CENTRAL GREAT  
BASIN, THE PACIFIC NORTHWEST, THE  
NORTHERN ROCKIES, AND THE NORTHERN GREAT BASIN, SAT-SUN, JUL  
30-JUL 31.  
- EXCESSIVE HEAT ACROSS PORTIONS OF THE LOWER MISSISSIPPI VALLEY  
AND THE SOUTHERN PLAINS, SAT-WED,  
JUL 30-AUG 3.  
- EXCESSIVE HEAT ACROSS PORTIONS OF THE CENTRAL PLAINS, THE LOWER  
MISSISSIPPI VALLEY, THE NORTHERN  
PLAINS, THE TENNESSEE VALLEY, THE MIDDLE MISSISSIPPI VALLEY, THE  
UPPER MISSISSIPPI VALLEY, AND THE  
OHIO VALLEY, MON-WED, AUG 1-AUG 3.  
 
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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