038  
FXUS01 KWBC 201935  
PMDSPD  
 
SHORT RANGE FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
334 PM EDT FRI JUN 20 2025  
 
VALID 00Z SAT JUN 21 2025 - 00Z MON JUN 23 2025  
 
...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PARTS OF THE  
UPPER MISSISSIPPI VALLEY/UPPER GREAT LAKES ON FRIDAY...  
 
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PARTS OF  
THE NORTHERN PLAINS/UPPER MISSISSIPPI VALLEY/UPPER GREAT LAKES ON  
FRIDAY...  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF  
THE UPPER/LOWER GREAT LAKES ON SATURDAY...  
 
...THERE IS A CRITICAL RISK OF FIRE WEATHER OVER PARTS OF THE  
GREAT BASIN/SOUTHWEST...  
 
A FRONT EXTENDING FROM THE GREAT LAKES TO THE NORTHERN HIGH PLAINS  
AND THEN SOUTHWESTWARD TO THE GREAT BASIN/CENTRAL CALIFORNIA WILL  
HAVE A WAVE OF LOW PRESSURE OVER THE NORTHERN HIGH PLAINS THAT  
MOVES TO THE UPPER MISSISSIPPI VALLEY BY SUNDAY EVENING. MOISTURE  
FROM THE WESTERN GULF OF AMERICA WILL STREAM NORTHWARD OVER THE  
MISSISSIPPI VALLEY AND OVERRUN THE BOUNDARY, TRIGGERING SHOWERS  
AND THUNDERSTORMS WITH HEAVY RAIN OVER THE UPPER MISSISSIPPI  
VALLEY AND INTO THE UPPER GREAT LAKES. THEREFORE, THE WPC HAS  
ISSUED A SLIGHT RISK (LEVEL 2/4) OF EXCESSIVE RAINFALL OVER PARTS  
OF THE UPPER MISSISSIPPI VALLEY/UPPER GREAT LAKES THROUGH SATURDAY  
MORNING. THE ASSOCIATED HEAVY RAIN WILL CREATE MAINLY LOCALIZED  
AREAS OF FLASH FLOODING, WITH URBAN AREAS, ROADS, SMALL STREAMS,  
AND LOW-LYING AREAS THE MOST VULNERABLE.  
 
FURTHERMORE, UPPER-LEVEL DYNAMICS AND UPPER-LEVEL ENERGY WILL  
CREATE SHOWERS AND SEVERE THUNDERSTORMS OVER PARTS OF THE NORTHERN  
PLAINS INTO THE UPPER GREAT LAKES. THEREFORE, THE SPC HAS ISSUED  
AN ENHANCED RISK (LEVEL 3/5) OF SEVERE THUNDERSTORMS OVER THE  
NORTHERN PLAINS/UPPER MISSISSIPPI VALLEY/UPPER GREAT LAKES THROUGH  
SATURDAY MORNING. THE HAZARDS ASSOCIATED WITH THESE THUNDERSTORMS  
ARE FREQUENT LIGHTNING, SEVERE THUNDERSTORM WIND GUSTS, HAIL, AND  
A FEW TORNADOES. HOWEVER, THERE WILL BE AN ADDED THREAT OF EF2 TO  
EF5 TORNADOS OVER NORTH DAKOTA AND NORTHWESTERN MINNESOTA. IN  
ADDITION, THERE WILL BE AN INCREASED THREAT OF SEVERE THUNDERSTORM  
WIND GUSTS OF 65 KNOTS OR GREATER AND HAIL TWO INCHES OR GREATER  
FROM THE NORTHERN PLAINS TO THE UPPER GREAT LAKES.  
 
MOREOVER, LOW PRESSURE OVER EASTERN CANADA WILL MOVE FARTHER  
NORTHEASTWARD OVER CANADA, PRODUCING SCATTERED RAIN WITH EMBEDDED  
THUNDERSTORMS OVER PARTS OF NORTHERN NEW ENGLAND THROUGH LATE  
FRIDAY NIGHT. ADDITIONALLY, MOISTURE AND UPPER-LEVEL ENERGY WILL  
PRODUCE SCATTERED SHOWERS AND THUNDERSTORMS OVER PARTS OF THE GULF  
COAST STATES AND THE SOUTHEAST/SOUTHERN MID-ATLANTIC COAST THROUGH  
SATURDAY MORNING.  
 
ON SATURDAY, THE AXIS OF SEVERE THUNDERSTORMS MOVES EASTWARD TO  
THE UPPER GREAT LAKES AND LOWER GREAT LAKES. THEREFORE, THE SPC  
HAS ISSUED A SLIGHT RISK (LEVEL 2/5) OF SEVERE THUNDERSTORMS OVER  
PARTS OF THE UPPER GREAT LAKES AND LOWER GREAT LAKES FROM SATURDAY  
THROUGH SUNDAY MORNING. THE HAZARDS ASSOCIATED WITH THESE  
THUNDERSTORMS ARE FREQUENT LIGHTNING, SEVERE THUNDERSTORM WIND  
GUSTS, HAIL, AND A FEW TORNADOES.  
 
LIKEWISE, ON SATURDAY, MOISTURE AND UPPER-LEVEL ENERGY WILL  
PRODUCE SCATTERED SHOWERS AND THUNDERSTORMS OVER PARTS OF THE GULF  
COAST STATES AND THE SOUTHEAST/SOUTHERN MID-ATLANTIC COAST THROUGH  
SUNDAY EVENING. SHOWERS AND THUNDERSTORMS WILL ALSO DEVELOP OVER  
PARTS OF THE NORTHEAST.  
 
MEANWHILE, AN UPPER-LEVEL LOW WILL MOVE ACROSS THE PACIFIC  
NORTHWEST INTO THE NORTHERN HIGH PLAINS BY SUNDAY. THE ENERGY WILL  
PRODUCE RAIN AND SNOW AT THE HIGHEST ELEVATIONS OVER THE CASCADES  
OVERNIGHT FRIDAY INTO SATURDAY AFTERNOON. RAIN WILL CONTINUE OVER  
THE NORTHWEST THROUGH SUNDAY AFTERNOON. FURTHER, WET MOUNTAIN SNOW  
WILL DEVELOP OVER PARTS OF THE NORTHERN ROCKIES LATE FRIDAY NIGHT,  
PROMPTING A WINTER STORM WARNING OVER PARTS OF GLACIER NATIONAL  
PARK FROM EARLY SATURDAY MORNING TO SUNDAY AFTERNOON. AT LOWER  
ELEVATIONS, SHOWERS AND THUNDERSTORMS WILL DEVELOP OVER THE REGION  
THROUGH SUNDAY EVENING. ALSO, SHOWERS AND THUNDERSTORMS WILL MOVE  
INTO PARTS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY ON  
SUNDAY.  
 
ELSEWHERE, DEEP BOUNDARY-LAYER MIXING IS EXPECTED ACROSS THE GREAT  
BASIN DURING THE AFTERNOON, WITH SURFACE TEMPERATURES CLIMBING  
INTO THE 90S TO 100 F AND RELATIVE HUMIDITY FALLING INTO THE  
SINGLE DIGITS. THE DEEP BOUNDARY-LAYER MIXING INTO THE STRONG FLOW  
ALOFT, COUPLED WITH A TIGHTENING REGIONAL PRESSURE GRADIENT, WILL  
CONTRIBUTE TO AN EXPANSIVE AREA OF 20-25 MPH SUSTAINED  
SOUTHWESTERLY SURFACE WINDS (WITH HIGHER GUSTS) HAVE PROMPTED A  
CRITICAL RISK OF FIRE WEATHER OVER PARTS OF THE GREAT  
BASIN/SOUTHWEST FRIDAY INTO SATURDAY.  
 
ZIEGENFELDER  
 
GRAPHICS AVAILABLE AT  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/BASICWX/BASICWX_NDFD.PHP  
 

 
 
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