008  
ACUS11 KWNS 121230  
SWOMCD  
SPC MCD 121230  
IAZ000-121430-  
 
MESOSCALE DISCUSSION 1948  
NWS STORM PREDICTION CENTER NORMAN OK  
0730 AM CDT WED AUG 12 2026  
 
AREAS AFFECTED...PARTS OF CENTRAL/SOUTH CENTRAL IOWA  
 
CONCERNING...SEVERE THUNDERSTORM WATCH 573...  
 
VALID 121230Z - 121430Z  
 
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 573  
CONTINUES.  
 
SUMMARY...THUNDERSTORM ACTIVITY SPREADING ACROSS THE MISSOURI RIVER  
CONTINUES TO GENERALLY WEAKEN, BUT RENEWED INTENSIFYING THUNDERSTORM  
DEVELOPMENT STILL APPEARS POSSIBLE NEAR THE I-80 CORRIDOR OF CENTRAL  
IOWA THROUGH 9-11 AM CDT. IF THIS OCCURS, IT COULD POSE A RISK FOR  
SEVERE HAIL AND DAMAGING DOWNBURSTS.  
 
DISCUSSION...TO THE EAST THROUGH SOUTHEAST OF A REMNANT MCV,  
2-HOURLY SURFACE PRESSURE RISES ON THE ORDER OF 2-5+ MB HAVE BEEN  
MAINTAINED, CENTERED AT 12Z IN A CORRIDOR ACROSS AND NORTH-NORTHEAST  
OF OMAHA NE INTO AREAS WEST OF CARROLL AND ATLANTIC IA. AHEAD OF  
THIS PERTURBATION, DEEPER BOUNDARY LAYER MOISTURE CONTENT  
CONCENTRATED ALONG A BAROCLINIC ZONE IN THE 925-850 MB LAYER  
CONTINUES TO PROVIDE SUPPORT FOR A NARROW PLUME OF SIZABLE CAPE NEAR  
THE I-80 CORRIDOR OF CENTRAL IOWA. SO, RENEWED INTENSIFYING  
THUNDERSTORM DEVELOPMENT STILL DOES NOT APPEAR OUT OF THE QUESTION  
INTO AND ACROSS THE DES MOINES AREA THROUGH MID MORNING. IF THIS  
OCCURS, A BELT OF CONVECTIVELY AUGMENTED WESTERLY MID-LEVEL FLOW IS  
CONTRIBUTING TO SUFFICIENT SHEAR TO SUPPORT ORGANIZATION, INCLUDING  
SUPERCELL STRUCTURES WITH POTENTIAL TO PRODUCE SEVERE HAIL AND  
LOCALLY STRONG DOWNBURSTS.  
 
..KERR.. 08/12/2026  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT  
 
ATTN...WFO...DMX...  
 
LAT...LON 42109433 42029254 41659238 41199253 40939268 40839335  
40819392 40999487 41399483 42109433  
 
MOST PROBABLE PEAK WIND GUST...55-70 MPH  
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN  
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