007  
FXUS01 KWBC 021925  
PMDSPD  
 
SHORT RANGE FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
325 PM EDT TUE SEP 02 2025  
 
VALID 00Z WED SEP 03 2025 - 00Z FRI SEP 05 2025  
 
...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PARTS OF  
SOUTHERN CALIFORNIA AND SOUTHWESTERN ARIZONA ON TUESDAY AND  
WEDNESDAY...  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF  
THE CENTRAL PLAINS AND MIDDLE MISSISSIPPI VALLEY ON WEDNESDAY...  
 
...THERE ARE EXTREME HEAT WARNINGS AND HEAT ADVISORIES OVER THE  
INTERIOR NORTHWEST...  
 
A WEAK FRONT EXTENDING FROM THE TENNESSEE VALLEY SOUTHWESTWARD TO  
THE SOUTHERN PLAINS WILL DISSIPATE BY WEDNESDAY. MOISTURE POOLING  
ALONG THE FRONT WILL AID IN PRODUCING SHOWERS AND THUNDERSTORMS  
OVER PARTS OF THE TENNESSEE VALLEY THROUGH WEDNESDAY AFTERNOON.  
 
MOREOVER, MONSOONAL MOISTURE, DIURNAL HEATING, AND UPPER-LEVEL  
IMPULSES WILL PRODUCE SHOWERS AND THUNDERSTORMS OVER  
CENTRAL/SOUTHERN CALIFORNIA, THE SOUTHWEST, AND THE GREAT BASIN  
THROUGH THURSDAY. HEAVY RAIN IS EXPECTED TO DEVELOP OVER PARTS OF  
SOUTHERN CALIFORNIA AND SOUTHWESTERN ARIZONA. THEREFORE, THE WPC  
HAS ISSUED A SLIGHT RISK (LEVEL 2/4) OF EXCESSIVE RAINFALL OVER  
SOUTHERN CALIFORNIA AND SOUTHWESTERN ARIZONA THROUGH WEDNESDAY  
MORNING. THE ASSOCIATED HEAVY RAIN WILL PRIMARILY CREATE  
LOCALIZED AREAS OF FLASH FLOODING, WITH URBAN AREAS, ROADS, SMALL  
STREAMS, AND LOW-LYING AREAS BEING THE MOST VULNERABLE.  
 
IN ADDITION, SHOWERS AND THUNDERSTORMS WITH HEAVY RAIN WILL  
DEVELOP OVER SOUTHERN CALIFORNIA AND SOUTHWESTERN ARIZONA ON  
WEDNESDAY INTO THURSDAY. THEREFORE, THE WPC HAS ISSUED A SLIGHT  
RISK (LEVEL 2/4) OF EXCESSIVE RAINFALL OVER SOUTHERN CALIFORNIA  
AND SOUTHWESTERN ARIZONA FROM WEDNESDAY THROUGH THURSDAY MORNING.  
THE ASSOCIATED HEAVY RAIN WILL PRIMARILY CREATE LOCALIZED AREAS OF  
FLASH FLOODING, WITH URBAN AREAS, ROADS, SMALL STREAMS, AND  
LOW-LYING AREAS BEING THE MOST VULNERABLE.  
 
MEANWHILE, A FRONT EXTENDING FROM THE UPPER MISSISSIPPI VALLEY  
ACROSS THE NORTHERN ROCKIES AND INTO THE NORTHERN HIGH PLAINS WILL  
MOVE SOUTH AND EASTWARD TO THE LOWER GREAT LAKES/CENTRAL  
APPALACHIANS INTO THE OHIO VALLEY BY THURSDAY. THE SYSTEM WILL  
PRODUCE SHOWERS AND THUNDERSTORMS OVER THE UPPER MISSISSIPPI  
VALLEY ON TUESDAY EVENING, MOVING ACROSS THE GREAT LAKES ON  
WEDNESDAY, AND INTO THE LOWER GREAT LAKES/NORTHEAST TO THE CENTRAL  
APPALACHIANS AND MID-ATLANTIC ON THURSDAY.  
 
ALONG THE SOUTHERN EDGE OF THE FRONT, SHOWERS AND SEVERE  
THUNDERSTORMS WILL DEVELOP OVER PARTS OF THE CENTRAL PLAINS/MIDDLE  
MISSISSIPPI VALLEY. THEREFORE, THE SPC HAS ISSUED A SLIGHT RISK  
(LEVEL 2/5) OF SEVERE THUNDERSTORMS OVER PARTS OF THE CENTRAL  
PLAINS/MIDDLE MISSISSIPPI VALLEY FROM WEDNESDAY THROUGH THURSDAY  
MORNING. THE HAZARDS ASSOCIATED WITH THESE THUNDERSTORMS ARE  
FREQUENT LIGHTNING, SEVERE THUNDERSTORM WIND GUSTS, HAIL, AND A  
MINIMAL THREAT OF TORNADOES. ADDITIONALLY, THERE IS AN INCREASED  
THREAT OF HAIL, TWO INCHES OR GREATER, OVER PARTS OF THE REGION.  
 
A SECOND FRONT WILL MOVE SOUTHWARD OUT OF WEST-CENTRAL CANADA  
OVERNIGHT WEDNESDAY, MOVING INTO THE UPPER MISSISSIPPI VALLEY BY  
THURSDAY EVENING. THE SYSTEM WILL PRODUCE SHOWERS AND  
THUNDERSTORMS OVER PARTS OF THE NORTHERN PLAINS BY THURSDAY  
MORNING AND INTO THE UPPER/MIDDLE MISSISSIPPI VALLEY BY THURSDAY  
EVENING. FURTHERMORE, A THIRD FRONT WILL LINGER OVER FLORIDA  
THROUGH THURSDAY. TROPICAL MOISTURE AND THE FRONT WILL AID IN  
PRODUCING SHOWERS AND THUNDERSTORMS OVER FLORIDA, ALSO THROUGH  
THURSDAY.  
 
LASTLY, AN UPPER-LEVEL RIDGE OVER THE NORTHWEST WILL ALLOW  
TEMPERATURES TO RISE INTO THE NINETIES AND THE TRIPLE DIGITS  
THROUGH THURSDAY. THE NWS HAS ISSUED EXTREME HEAT WARNINGS AND  
HEAT ADVISORIES OVER THE INTERIOR NORTHWEST.  
 
ZIEGENFELDER  
 
GRAPHICS AVAILABLE AT  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/BASICWX/BASICWX_NDFD.PHP  
 
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