798  
FXUS63 KDMX 110716  
AFDDMX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DES MOINES IA  
ISSUED BY NATIONAL WEATHER SERVICE DULUTH MN  
216 AM CDT FRI JUL 11 2025  
   
KEY MESSAGES
 
 
- FLOOD WATCH FOR FLASH FLOODING BETWEEN US HIGHWAYS 34 AND 20  
THROUGH 7AM CDT THIS MORNING. WIDESPREAD RAINFALL TOTALS  
BETWEEN 2 AND 3 INCHES WITH LOCALLY HIGHER AMOUNTS.  
 
- FLOOD WATCH FOR FLASH FLOODING FOR THE REMAINDER OF THE DAY  
FRIDAY FROM THE WATERLOO THROUGH CORYDON AREAS AND POINTS EAST  
FOR ANOTHER ROUND OF HEAVY RAINFALL THIS AFTERNOON AND  
EVENING.  
 
- SCATTERED SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING  
ACROSS PORTIONS OF CENTRAL IOWA (RISK LEVEL 2 OUT OF 5).  
DAMAGING WINDS AND A TORNADO OR TWO ARE THE PRIMARY THREATS IN  
ADDITION TO HEAVY RAIN.  
 

 
   
DISCUSSION
 
 
ISSUED AT 104 AM CDT FRI JUL 11 2025  
 
A LONG LIVED MCS WITH DAMAGING WINDS WILL CONTINUE TO PROPAGATE  
EAST ACROSS THE I-80 CORRIDOR EARLY THIS MORNING, SUSTAINED BY  
A LOW LEVEL JET AND ALONG A GRADIENT OF STEEP MID LEVEL LAPSE  
RATES AND DOWNDRAFT CAPE. IN THIS WAKE OF THIS LEADING MCS,  
TRAINING CONVECTION ALONG A STATIONARY FRONT SUSTAINED BY THE  
LOW LEVEL JET WITH A PRECIPITABLE WATER AXIS AROUND 2.00 INCHES  
WILL YIELD HEAVY RAINFALL AND A FLASH FLOOD THREAT BETWEEN US  
HIGHWAYS 34 AND 20. RAINFALL TOTALS BETWEEN 2.00 AND 3.00 INCHES  
ARE LIKELY FOR MANY LOCATIONS, WITH LOCALLY HIGHER AMOUNTS IN  
EXCESS OF 4.00 INCHES. A FLOOD WATCH REMAINS IN EFFECT FOR THESE  
AREAS UNTIL 7 AM CDT THIS MORNING.  
 
FOR THIS AFTERNOON AND EVENING, ANOTHER ROUND OF STRONG TO  
SEVERE STORMS WITH HEAVY RAINFALL IS EXPECTED. ISSUED A SECOND  
FLOOD WATCH FOR THE WATERLOO THROUGH CORYDON AREAS AND POINTS  
EAST FOR ANOTHER ROUND OF HEAVY RAINFALL WITH PRECIPITABLE WATER  
VALUES REMAINING NEAR 2.00 INCHES WITH TRAINING CONVECTION  
LIKELY ALONG THE SLOW MOVING FRONTAL BOUNDARY. ADDITIONAL RAINFALL  
AMOUNTS OF ONE AND A HALF TO THREE INCHES ARE POSSIBLE FOR  
THESE AREAS, SUPPORTED BY THE HREF LPMM QPF, MPAS CAMS AND RRFS.  
THIS ALSO ALIGNS WELL WITH THE WPC SLIGHT RISK IN THE EXCESSIVE  
RAINFALL OUTLOOK FOR TODAY (LEVEL 2 OUT OF 4).  
 
REGARDING THE SEVERE RISK FOR TODAY, SPC HAS MUCH OF SOUTH  
CENTRAL INTO EASTERN IOWA IN A SLIGHT RISK FOR SEVERE  
THUNDERSTORMS (LEVEL 2 OUT OF 5). PLENTIFUL MOISTURE AND  
BUOYANCY WITH MLCAPE ON THE ORDER OF 2000-3000 J/KG WITH  
DAYTIME HEATING WILL BE IN PLACE ALONG AND AHEAD OF A SLOW  
MOVING FRONTAL BOUNDARY. DEEP LAYER SHEAR AROUND 30-40KTS  
AUGMENTED BY AN APPROACHING SHORTWAVE THIS AFTERNOON WILL  
PROMOTE ANOTHER ROUND OF SEVERE THUNDERSTORMS. OUTFLOW  
BOUNDARIES FROM MORNING CONVECTION WILL HAVE TO BE SORTED OUT  
FOR THEIR MESOSCALE IMPACTS ON THE THERMODYNAMIC AND KINEMATIC  
SETUP. STILL, INITIAL SUPERCELL STRUCTURES ARE FAVORED WITH A  
TORNADO OR TWO POSSIBLE WITH LARGE LOW LEVEL CURVATURE IN THE  
FORECAST HODOGRAPHS AND LOW CLOUD BASES. AS STORMS BECOME MORE  
NUMEROUS IN THE LATE AFTERNOON AND EVENING, UPSCALE GROWTH IS  
EXPECTED WITH DAMAGING WINDS BECOMING THE PRIMARY THREAT.  
 

 
   
AVIATION /06Z TAFS THROUGH 06Z SATURDAY/
 
 
ISSUED AT 203 AM CDT FRI JUL 11 2025  
 
THUNDERSTORMS WILL CONTINUE TO MOVE ACROSS THE TERMINALS FOR THE  
NEXT FEW HOURS. DSM AND OTM TO BE MOST STRONGLY AFFECTED FOR THE  
NEXT FEW HOURS, WITH STRONG WIND GUSTS AND IFR VISIBILITIES AND MVFR  
CEILINGS. THE OTHER TERMINALS TO GET MVFR TO POTENTIALLY IFR  
CONDITIONS IN THUNDERSTORMS WITH HEAVY RAIN. A PERIOD OF MVFR  
CEILINGS ARE POSSIBLE, A 50 TO 70 PERCENT CHANCE, FRIDAY MORNING,  
MAINLY FOR KALO AND KMCW. RAIN SHOWER AND THUNDERSTORM TO  
TEMPORARILY DECREASE FRIDAY MORNING IN THE 12-17Z TIMEFRAME, BEFORE  
INCREASING ONCE AGAIN WITH DAYTIME HEATING. FRIDAY AFTERNOON STORMS  
TO MOST LIKELY AFFECT KDSM, KOTM AND KALO, WITH LOWER PROBABILITIES  
FOR KFOD AND KMCW.  
 

 
   
DMX WATCHES/WARNINGS/ADVISORIES
 
 
FLOOD WATCH UNTIL 7 AM CDT THIS MORNING FOR IAZ033>037-044>048-  
057>060-070>073.  
FLOOD WATCH THROUGH LATE TONIGHT FOR IAZ038-039-049-050-061-  
062-074-075.  
FLOOD WATCH FROM 7 AM CDT THIS MORNING THROUGH LATE TONIGHT  
FOR IAZ084>086-095>097.  
 

 
 

 
 
DISCUSSION...DLH  
AVIATION...DLH  
 
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