533  
FXUS02 KWBC 050643  
PMDEPD  
 
EXTENDED FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
243 AM EDT SAT JUL 5 2025  
 
VALID 12Z TUE JUL 08 2025 - 12Z SAT JUL 12 2025  
 
...HAZARDOUS HEAT AND HUMIDITY OVER PARTS OF THE EAST; BUILDING  
OVER THE WEST...  
 
   
..PATTERN OVERVIEW
 
 
QUASI-ZONAL FLOW OVER MOST OF THE CONUS TO START THE WEEK WILL  
TRANSITION TOWARD AN UPPER HIGH STARTING TO TAKE RESIDENCE NEAR LAS  
VEGAS AND INCREASED TROUGHING INTO THE NORTHEAST. THIS WILL FAVOR  
A FAIRLY TYPICAL SUMMERTIME PATTERN BUT WITHOUT MUCH, IF ANY,  
MONSOON SIGNAL INTO THE SOUTHWEST.  
 
...GUIDANCE/PREDICTABILITY ASSESSMENT  
 
THE LARGE SCALE PATTERN REMAINS IN GOOD AGREEMENT THROUGH THE  
EXTENDED PERIOD. LIKE ITS PREVIOUS RUNS, THE GFS AND THE GEFS MEAN  
WERE PERSISTENT IN BEING THE FASTER SOLUTIONS FROM THE NORTHEAST  
PACIFIC INTO WESTERN NORTH AMERICA THAN THE OTHER MODELS THEREFORE  
HAD LIMITED INCLUSION IN THE FORECAST. THE PREFERRED BLEND WAS A  
COMPRISE OF THE 12Z ECMWF/CANADIAN/UKMET/ECMWF ENSEMBLE MEAN AND  
THE NBM.  
   
..WEATHER/HAZARDS HIGHLIGHTS
 
 
SHOWERS AND THUNDERSTORMS ARE EXPECTED TO BE FOCUSED IN PROXIMITY  
TO PROGRESSIVE COLD FRONTS, STALLED BOUNDARIES AND ROUND THE UPPER  
HIGH IN THE SOUTHERN ROCKIES. THE WAVY FRONT INTO THE EASTERN U.S.  
MAY BE A FOCUS FOR HEAVIER RAIN AND THUNDERSTORMS. THIS INCLUDES  
AREAS FROM THE CORN BELT INTO THE MIDWEST AND OHIO VALLEY,  
APPALACHIANS, MID-ATLANTIC, AND NORTHEAST. THERE ARE MARGINAL RISKS  
IN PLACE (LEVEL 1 OF 4) FOR THE SOUTHWEST, CENTRAL PLAINS/MIDWEST  
TO THE UPPER MISSISSIPPI VALLEY/UPPER GREAT LAKES REGION AND  
PORTIONS OF THE NORTHEAST FOR DAY 4 AND FOR THE MID-MISSISSIPPI  
VALLEY/MIDWEST FOR DAY 5.  
 
HEIGHTS ACROSS THE NORTHEAST AND MID-ATLANTIC REGIONS WILL  
GRADUALLY LOWER AS TROUGHING MOVES IN. WITH THE HIGHER HEIGHTS  
SHIFTING SOUTHWARD THE HEAT WILL INCREASE AS WELL AS BEGIN TO BUILD  
TO THE WEST AS THE UPPER HIGH STRENGTHENS OVER THE SOUTHWEST. MANY  
LOCATIONS WILL HAVE DAILY MAXIMUMS CLIMBING WELL INTO THE 100S AT  
LOWER ELEVATIONS WHICH WILL GREATLY LIMIT RAIN EXCEPT FOR PERHAPS  
FAR SOUTHEASTERN AZ INTO NM EARLY IN THE WEEK. EXPERIMENTAL  
HEATRISK VALUES MAY RISE TO MAJOR OR EXTREME LEVELS (3 OUT OF 4 OR  
4 OUT OF 4) FROM THE CALIFORNIA DESERTS INTO SOUTHERN NEVADA, UTAH,  
AND ARIZONA.  
 
CAMPBELL/FRACASSO  
 
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 FORECAST (QPF), EXCESSIVE RAINFALL  
OUTLOOK (ERO), WINTER WEATHER OUTLOOK (WWO) PROBABILITIES, HEAT  
INDICES, AND KEY MESSAGES CAN BE ACCESSED FROM:  
 
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  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/#PAGE=OVW  
 

 
 
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