148  
FXUS01 KWBC 271920  
PMDSPD  
 
SHORT RANGE FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
320 PM EDT MON JUL 27 2026  
 
VALID 00Z TUE JUL 28 2026 - 00Z THU JUL 30 2026  
 
...RISK FOR SEVERE THUNDERSTORMS AND FLASH FLOODING WILL SPREAD  
FROM THE GREAT LAKES/OHIO VALLEY TO THE NORTHEAST OVER THE NEXT  
FEW DAYS; MODERATE RISK OF EXCESSIVE RAINFALL FOR THE NORTHERN  
MID-ATLANTIC/SOUTHERN NEW ENGLAND TUESDAY...  
 
...DANGEROUS HEAT WAVE CONTINUES OVER PARTS OF SOUTHERN U.S. INTO  
THIS WEEK...  
 
...ACTIVE MONSOONAL MOISTURE FUELS THUNDERSTORMS OVER THE FOUR  
CORNERS REGION, ROCKIES, AND HIGH PLAINS...  
 
SCATTERED TO WIDESPREAD THUNDERSTORMS ARE FORECAST INTO THIS  
EVENING ACROSS THE GREAT LAKES AND SOUTH INTO THE OHIO VALLEY AS  
UPPER-ENERGY ROUNDS A TROUGH ALONG THE EAST COAST AND FRONTAL  
BOUNDARIES HELP FORCE STORM DEVELOPMENT. PLENTIFUL  
MOISTURE/INSTABILITY AS WELL AS SUFFICIENT UPPER-LEVEL SHEAR HAS  
LED TO AN ENHANCED RISK OF SEVERE WEATHER (LEVEL 3/5) FROM THE  
STORM PREDICTION CENTER. CLUSTERING/POTENTIALLY ORGANIZED  
THUNDERSTORMS WILL BRING A THREAT FOR DAMAGING WINDS, POSSIBLY  
SIGNIFICANT, AS WELL AS SOME LARGE HAIL AND POSSIBLY A TORNADO.  
PLENTIFUL MOISTURE IN PLACE WILL ALSO BRING A THREAT FOR HEAVY  
RAINFALL, WITH A SLIGHT RISK OF EXCESSIVE RAINFALL (LEVEL 2/4) IN  
PLACE FOCUSED ON EASTERN ILLINOIS AND NORTHWESTERN INDIANA, WHERE  
SOME SCATTERED INSTANCES OF FLASH FLOODING ARE POSSIBLE. MORE  
ISOLATED INSTANCES WILL REMAIN POSSIBLE ELSEWHERE THROUGH THE  
REGION.  
 
ON TUESDAY, ADDITIONAL UPPER ENERGY WILL HELP TO BOTH STRENGTHEN  
THE TROUGH, LEADING TO A CLOSED LOW ALOFT, AS WELL AS  
REINFORCE/STRENGTHEN THE EASTWARD PROGRESSING FRONTAL SYSTEM. THE  
COMBINATION OF INTENSE UPPER FORCING MORE REMINISCENT OF FALL THAN  
SUMMER AND WARM, ANOMALOUSLY MOIST AIR FLOWING IN FROM THE  
ATLANTIC WILL LEAD TO WIDESPREAD, VERY HEAVY RAINFALL PRODUCING  
STORMS FROM THE CAROLINAS NORTH THROUGH THE APPALACHIANS,  
MID-ATLANTIC, AND INTO NEW ENGLAND. THE GREATEST CONCENTRATION AND  
POTENTIAL FOR MULTIPLE ROUNDS OF STORMS IS EXPECTED TO FOCUS ON  
PORTIONS OF THE NORTHERN MID-ATLANTIC/SOUTHERN NEW ENGLAND WHERE A  
MODERATE RISK OF EXCESSIVE RAINFALL HAS BEEN INCLUDED (LEVEL 3/4)  
FOR THE THREAT OF SCATTERED TO NUMEROUS AND POTENTIALLY  
SIGNIFICANT INSTANCES OF FLASH FLOODING. A BROADER SLIGHT RISK  
(LEVEL 2/3) ACROSS THE MID-ATLANTIC/SOUTHERN NEW ENGLAND COVERS  
MORE SCATTERED INSTANCES OF FLASH FLOODING WITH ISOLATED INSTANCES  
POSSIBLE ELSEWHERE THROUGH THE REGION. ADDITIONAL SEVERE  
THUNDERSTORMS WILL BE POSSIBLE AS WELL PARTICULARLY ACROSS THE  
CAROLINAS AND CENTRAL/SOUTHERN MID-ATLANTIC WHERE THE SPC HAS  
INCLUDED ANOTHER SLIGHT RISK FOR THE THREAT OF DAMAGING WINDS AS  
WELL AS SOME HAIL AND A FEW TORNADOES. THE FOCUS WILL SHIFT A BIT  
FURTHER TO THE NORTHEAST AND INTO SOUTHERN NEW ENGLAND ON  
WEDNESDAY WHERE ANOTHER SLIGHT RISK OF EXCESSIVE RAINFALL IS IN  
EFFECT FOR ADDITIONAL SCATTERED INSTANCES OF FLASH FLOODING.  
 
AN ACTIVE MONSOONAL PATTERN REMAINS IN PLACE OVER THE FOUR CORNERS  
REGION AS WELL AS PORTIONS OF THE CENTRAL ROCKIES AND ADJACENT  
HIGH PLAINS. DAILY ROUNDS OF THUNDERSTORMS WILL BRING LOCALLY  
HEAVY DOWNPOURS WITH AT LEAST AN ISOLATED RISK OF FLASH FLOODING.  
THERE IS NOW A SLIGHT RISK OF EXCESSIVE RAINFALL IN EFFECT FOR  
PORTIONS OF EASTERN ARIZONA, WESTERN/NORTHERN NEW MEXICO, AND  
EASTERN COLORADO FOR TUESDAY AS SUPPRESSION OF THE UPPER-RIDGE  
WILL ALLOW FOR MORE WIDESPREAD THUNDERSTORMS AND RAINFALL LEADING  
TO A FEW MORE SCATTERED INSTANCES OF FLASH FLOODING. URBAN AREAS  
AS WELL AS BURN SCARS WILL REMAIN MOST SENSITIVE TO ADDITIONAL  
HEAVY RAINFALL. ELSEWHERE, DAILY THUNDERSTORM CHANCES WILL  
CONTINUE ACROSS PORTIONS OF FLORIDA AND THE GULF COAST, WITH  
ISOLATED FLASH FLOODING POSSIBLE.  
 
A DANGEROUS HEAT WAVE WILL SETTLE OVER PORTIONS OF THE SOUTHERN  
U.S. THIS WEEK AS A BROAD AND STRONG UPPER-RIDGE REMAINS IN PLACE.  
HIGH TEMPERATURES IN THE MID- TO UPPER 90S, LOCALLY INTO THE LOW  
100S, AS WELL AS OPPRESSIVE HUMIDITY WILL LEAD TO HEAT INDICES IN  
THE 105-115 DEGREE RANGE. THIS WILL RESULT IN AREAS OF MAJOR TO  
EXTREME HEATRISK (LEVELS 3 AND 4 OUT OF 4), INDICATING A LEVEL OF  
HEAT DANGEROUS TO ANYONE WITHOUT ADEQUATE COOLING OR HYDRATION.  
CONDITIONS WILL ALSO REMAIN HOT ACROSS MUCH OF THE INTERIOR WEST  
WITH HIGHS IN THE 90S AND DESERT SOUTHWEST WITH HIGHS IN THE 100S  
TO LOW 110S. CONDITIONS WILL BE MORE VARIABLE FURTHER NORTH OVER  
THE CENTRAL U.S. INCLUDING THE CENTRAL/NORTHERN PLAINS WHERE  
VARIOUS FRONTAL PASSAGES AS WELL AS SOME STORM CHANCES WILL HELP  
TO KEEP TEMPERATURES DOWN LOCALLY, BUT SOME HIGHS IN THE 90S TO  
100 WILL CONTINUE, PARTICULARLY ACROSS THE NORTHERN PLAINS.  
MEANWHILE, TEMPERATURES WILL BE MUCH MORE MILD FOR SUMMER OVER THE  
NORTHEAST AND PACIFIC NORTHWEST WITH HIGHS MAINLY IN THE 70S AND  
80S.  
 
PUTNAM  
 
GRAPHICS AVAILABLE AT  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/BASICWX/BASICWX_NDFD.PHP  
 

 
 
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