939  
FXUS02 KWNH 090628  
PREEPD  
 
EXTENDED FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
228 AM EDT WED JUL 9 2025  
 
VALID 12Z SAT JUL 12 2025 - 12Z WED JUL 16 2025  
 
*** HEAVY RAIN WITH POTENTIAL FOR FLASH FLOODING FOR  
SOUTHERN/CENTRAL PLAINS. ***  
 
   
..PATTERN OVERVIEW  
 
AN UPPER LOW WITH SEVERAL WAVES OF EMBEDDED SHORTWAVE ENERGY WILL  
PROPAGATE ACROSS SOUTH-CENTRAL CANADA AND THE NORTHERN/CENTRAL TIER  
OF THE U.S. OVER THE NEXT WEEK. A PAIR OF SURFACE COLD FRONTS WILL  
MOVE THROUGH THE PLAINS AND MIDWEST RESPECTIVELY, ACTING AS A FOCUS  
FOR STORMS. A RETROGRADING SUBTROPICAL RIDGE WILL KEEP THINGS  
WARMER THAN AVERAGE ACROSS THE SOUTHERN TIER.  
 
...GUIDANCE/PREDICTABILITY ASSESSMENT  
 
THE LATEST GUIDANCE REMAINS IN GOOD AGREEMENT WITH THE BROAD UPPER  
LEVEL RIDGING ACROSS THE SOUTHERN TIER OF THE COUNTRY WITH  
DIFFERENCES  
AROUND TIMING AND PLACEMENT OF SHORTWAVES SPINNING THROUGH THE  
BASE OF THE PARENT LOW TO THE NORTH. IT WAS PREVIOUSLY NOTED THAT  
THE  
06Z ECMWF AIFS WAS MORE EXTREME THAN THE REST OF THE GUIDANCE WHEN  
IT COMES TO MAX/MIN TS, WHILE THE 00Z CMC HAS A MUCH HIGHER  
MAGNITUDE QPF FOOTPRINT THAN THE GFS/EC/UK SUITE OVER THE PLAINS  
AND UPPER MIDWEST THROUGHOUT THE PERIOD. THIS TREND PERSISTED WITH  
THE LATEST MODEL RUN.  
 
WPC UTILIZED A STARTING POINT OF THE EC/CMC/GFS/UKMET BEFORE  
INCLUDING GEFS MEAN, NAEFS MEAN AND ECMWF ENSEMBLE MEAN BY MID  
PERIOD AND INCREASING THE WEIGHTING THROUGH THE LATER PERIODS.  
   
..WEATHER/HAZARDS HIGHLIGHTS  
 
SCATTERED CONVECTION ANTICIPATED TO FIRE AHEAD OF, AND ALONG  
PROGRESSIVE  
COLD FRONTS, STALLED BOUNDARIES AND ROUND THE UPPER HIGH IN THE  
SOUTHERN ROCKIES. THE EXACT LOCATION OF ANTICIPATED HIGHER QPF  
AMOUNTS REMAIN A BIT UNCERTAIN GIVEN PERSISTENT MODEL DIFFERENCES,  
NEVERTHELESS, THERE IS POTENTIAL FOR ISOLATED INSTANCES OF  
EXCESSIVE RAINFALL AND LOCALIZED FLASH FLOODING.  
 
FOR DAY 4, THERE IS A SLIGHT RISK FOR EXCESSIVE RAIN FOR PORTIONS  
OF KANSAS AND OKLAHOMA WHERE A MCS WILL LIKELY SETUP AND AN  
ENVELOPING BROAD MARGINAL RISK ENVELOPING FROM THE SOUTHERN PLAINS  
EAST TO PENNSYLVANIA AND NORTH TO THE MINNESOTA ARROWHEAD. ANOTHER  
DAY 4 MARGINAL RISK AREA IS IN EFFECT FOR EASTERN NEW MEXICO INTO  
THE TEXAS PANHANDLE. THE POTENTIAL FOR HEAVY RAINFALL NEAR THE  
FRONT BOUNDARY OVER THE CENTRAL U.S. WILL PERSIST THEREFORE A  
MARGINAL RISK WAS RAISED FOR DAY 5 FOR PORTIONS OF THE SOUTHERN  
PLAINS, MIDWEST INTO THE OHIO VALLEY. CONVECTION ALONG THE EASTERN  
COAST OF FLORIDA MAY LEAD TO ISOLATED FLASH FLOODING/PONDING IN  
URBAN AREAS SO A SMALL MARGINAL RISK AREA WAS RAISED FOR DAY 5 AS  
WELL. ALTHOUGH THERE IS FAIR AMOUNT OF SPREAD IN QPF PLACEMENT, A  
COUPLE MODEL SOLUTIONS ARE HINTING AT A CONCENTRATION OF QPF NEAR  
PARTS OF EASTERN NEW MEXICO/WEST TEXAS AND FOR SOUTHERN PARTS OF  
THE HILL COUNTRY. CONFIDENCE IS LOW AT THIS TIME BUT WORTH NOTING  
THAT THIS AREA WILL CONTINUE TO BE MONITORED GIVEN THE EXTREME  
SENSITIVITY WITH ONGOING FLOODING.  
 
NUMEROUS LOCATIONS WILL HAVE DAILY READING ABOVE 100, WITH SEVERAL  
NEARING THE 110S IN THE LOWER ELEVATIONS. CONDITIONS WILL MAINLY BE  
DRY ACROSS THE WEST/SOUTHWEST, EXCEPT FOR PERHAPS FAR SOUTHEASTERN  
ARIZONA INTO NEW MEXICO WHERE SOME MONSOONAL MOISTURE MAY BE  
PRESENT.  
 
CAMPBELL  
 
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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