563  
FXUS01 KWBC 060825  
PMDSPD  
 
SHORT RANGE FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
424 AM EDT SUN APR 06 2025  
 
VALID 12Z SUN APR 06 2025 - 12Z TUE APR 08 2025  
 
...SIGNIFICANT HEAVY RAINFALL AND FLASH FLOOD THREAT SHIFTS  
EASTWARD INTO PARTS OF THE CENTRAL/SOUTHERN APPALACHIANS AND  
SOUTHEAST SUNDAY...  
 
...SEVERE WEATHER RISKS FOR PORTIONS OF THE SOUTHERN MID-ATLANTIC  
AND SOUTHEAST SUNDAY AND MONDAY...  
 
...SERIES OF FRONTAL SYSTEMS TO BRING BOUTS OF UNSETTLED WEATHER  
TO THE PACIFIC NORTHWEST AND NORTHERN ROCKIES THE NEXT FEW DAYS...  
 
...WINTRY WEATHER RETURNS TO THE GREAT LAKES AND NORTHEAST THROUGH  
THE EARLY PART OF THE WEEK...  
 
...AMPLIFIED FLOW PATTERN LEADS TO LARGE TEMPERATURE SWINGS ACROSS  
THE CONTINENTAL U.S. THE NEXT FEW DAYS...  
 
AFTER SEVERAL DAYS OF EXTREME RAINFALL AND DEVASTATING FLOODING  
ACROSS PARTS OF THE OHIO VALLEY, MID-SOUTH, MIDDLE AND LOWER  
MISSISSIPPI VALLEYS, THE THREAT FOR SIGNIFICANT HEAVY RAINFALL AND  
FLASH FLOODING SHIFTS EASTWARD INTO THE APPALACHIANS AND SOUTHEAST  
ON SUNDAY. THE FRONTAL BOUNDARY WHICH HAD BEEN STUBBORNLY SLOW TO  
MOVE AND CAUSED REPEATED ROUNDS OF TORRENTIAL DOWNPOURS ACROSS THE  
REGION IS FINALLY BEGINNING TO PUSH EASTWARD, TAKING WITH IT THE  
EXCESSIVE RAINFALL THREAT THAT CAUSED LIFE-THREATENING FLASH  
FLOODING FOR MANY. WITH ITS EASTWARD PUSH, MOISTURE ALONG AND  
AHEAD OF THE FRONT WILL BECOME FOCUSED FROM THE APPALACHIANS TO  
THE CENTRAL GULF COAST, SETTING THE STAGE FOR INTENSE DOWNPOUR  
PRODUCING THUNDERSTORMS THROUGHOUT THE DAY. A BROAD SLIGHT RISK  
(LEVEL 2/4) REMAINS IN PLACE WHILE A TARGETED MODERATE RISK (LEVEL  
3/4) HAS BEEN INTRODUCED ACROSS CENTRAL ALABAMA AND EXTREME  
WEST-CENTRAL GEORGIA. THE FORWARD SPEED OF THE FRONT SHOULD  
PREVENT THE LEVEL OF CATASTROPHIC FLOODING SEEN IN PREVIOUS DAYS,  
BUT STORMS WITH HEAVY RAINFALL THAT LOCALLY TRACK OVER THE SAME  
AREAS MAY STILL LEAD TO SIGNIFICANT INSTANCES OF FLASH FLOODING.  
FORTUNATELY, THE RISK OF HEAVY RAINFALL AND FLASH FLOODING  
DECREASES SIGNIFICANTLY ON MONDAY, WITH JUST A MARGINAL RISK  
(LEVEL 1/4) HIGHLIGHTED FROM SOUTHEAST VIRGINIA TO NORTHERN  
FLORIDA.  
 
SIMILAR TO THE FLOODING THREAT, THE RISK FOR SEVERE WEATHER ALSO  
SHIFTS EASTWARD SUNDAY INTO MONDAY, TARGETING PARTS OF THE  
SOUTHERN MID-ATLANTIC AND SOUTHEAST AS WE ROUND OUT THE WEEKEND  
AND START THE NEW WORK WEEK. MOISTURE, INSTABILITY, AND WIND SHEAR  
ALONG AND AHEAD OF THE EASTWARD ADVANCING COLD FRONT WILL SUPPORT  
A BROKEN LINE OF STRONG TO SEVERE THUNDERSTORMS ACROSS THE REGION,  
WITH THE MOST SEVERE STORMS CAPABLE OF PRODUCING DAMAGING WIND  
GUSTS AND EVEN A FEW TORNADOES. THE STORM PREDICTION CENTER  
CONTINUES TO MAINTAIN SLIGHT RISKS (LEVEL 2/5) FROM NORTHERN  
GEORGIA TO THE CENTRAL GULF COAST ON SUNDAY, AND FROM SOUTHEAST  
GEORGIA TO NORTHERN FLORIDA ON MONDAY. FARTHER NORTH ACROSS  
PORTIONS OF THE APPALACHIANS AND SOUTHERN MID-ATLANTIC, MARGINAL  
RISKS (LEVEL 1/5) ARE IN EFFECT TO ACCOUNT FOR THE POTENTIAL FOR  
STRONGER STORMS TO PRODUCE DAMAGING WINDS.  
 
A SERIES OF FRONTS WILL BRING EPISODES OF UNSETTLED WEATHER TO THE  
PACIFIC NORTHWEST ON SUNDAY AND THE NORTHERN ROCKIES/INTERMOUNTAIN  
WEST MONDAY INTO TUESDAY. THESE FRONTAL SYSTEMS WILL PUSH INLAND  
FROM THE PACIFIC, BRINGING MOISTURE AND INTERMITTENT SHOWERS TO  
MUCH OF THE REGION. RAIN WILL FALL ACROSS COASTAL LOCATIONS AND  
THE LOWER ELEVATIONS WHILE SNOW WILL FLY IN THE HIGH COUNTRY. AS  
THESE FRONTS CROSS THE TERRAIN, THEY WILL WEAKEN AND EVENTUALLY  
DISSIPATE. AS A RESULT, RAIN AND SNOW AMOUNTS WILL BECOME  
INCREASINGLY LIGHTER WITH EASTERN EXTENT. THE HIGHEST SNOWFALL  
TOTALS WILL MOSTLY BE CONFINED TO THE HIGHER ELEVATIONS OF THE  
OLYMPIC MOUNTAINS AND THE CASCADES WHERE SEVERAL INCHES UP TO 1 TO  
3 FEET WILL FALL.  
 
TO THE NORTH OF THE FLOODING AND SEVERE THREATS, AND ON THE COLDER  
SIDE OF THE EASTERN U.S. FRONTAL BOUNDARY, WINTRY WEATHER WILL  
RETURN TO PARTS OF THE GREAT LAKES AND THE NORTHEAST THROUGH THE  
EARLY PART OF THE UPCOMING WEEK. ON SUNDAY, AS THE RAIN ASSOCIATED  
WITH A DEPARTING SYSTEM ENDS, SNOW MAY MIX IN ACROSS SOME OF THE  
HIGHER ELEVATIONS IN NORTHERN NEW ENGLAND. ANY ACCUMULATIONS WOULD  
BE LIGHT. COLDER AIR FILTERS IN ON SUNDAY NIGHT, SETTING THE STAGE  
FOR MORE WIDESPREAD WINTRY WEATHER ON MONDAY AS A DEVELOPING WAVE  
OF LOW PRESSURE MOVES IN FROM THE SOUTHWEST. PARTS OF THE  
NORTHEAST, AND ESPECIALLY NORTHERN NEW ENGLAND, STAND TO SEE A  
MODEST SNOWFALL WITH FORECAST ACCUMULATIONS OF AT LEAST A FEW  
INCHES, WITH THE POTENTIAL FOR MORE THAN 6 INCHES IN THE HIGHER  
ELEVATIONS. JUST TO THE SOUTH OF THE SNOW, A WINTRY MIX OF SNOW,  
SLEET, AND POSSIBLY FREEZING RAIN WILL MAKE FOR SLIPPERY  
CONDITIONS ACROSS PORTIONS OF NORTHERN PENNSYLVANIA, NEW YORK, AND  
SOUTHERN NEW ENGLAND. THEN ON TUESDAY, A REINFORCING BLAST OF MUCH  
COLDER AIR WILL BRING SNOW TO THE GREAT LAKES REGION, WITH BANDS  
OF LAKE-EFFECT SNOW DOWNWIND.  
 
LARGE TEMPERATURE SWINGS CAN BE EXPECTED ACROSS THE CONTINENTAL  
U.S. THE NEXT FEW DAYS AS AN AMPLIFIED FLOW PATTERN REMAINS IN  
PLACE. WELL ABOVE NORMAL WARMTH ACROSS THE MID-ATLANTIC AND  
SOUTHEAST ON SUNDAY WILL GIVE WAY TO MUCH COLDER AIR MONDAY AND  
ESPECIALLY TUESDAY AS REINFORCING COLD FRONTS MAKE THEIR WAY  
THROUGH. JUST TO THE WEST, THE COLDEST ANOMALIES ON SUNDAY WILL BE  
FOUND FROM THE EASTERN GREAT LAKES TO THE SOUTHERN PLAINS, WITH  
TEMPERATURES MAKING IT FEEL MORE LIKE WINTER THAN SPRING. AN  
OVERALL WARMING TREND CONTINUES ACROSS THE WESTERN U.S. THROUGH  
THE EARLY PART OF THE WEEK, THOUGH THE UNSETTLED WEATHER EXPECTED  
ACROSS THE PACIFIC NORTHWEST MAY PUT A DAMPER ON THE WARM UP. BY  
TUESDAY, ABOVE NORMAL WARMTH WILL SPREAD FROM THE WEST INTO THE  
PLAINS, WHILE THE EASTERN HALF OF THE COUNTRY FROM THE GREAT LAKES  
TO FLORIDA EXPERIENCE TEMPERATURES THAT ARE MUCH COLDER THAN  
AVERAGE.  
 
MILLER  
 
GRAPHICS AVAILABLE AT  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/BASICWX/BASICWX_NDFD.PHP  
 
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