072  
ACUS11 KWNS 151652  
SWOMCD  
SPC MCD 151651  
IAZ000-151845-  
 
MESOSCALE DISCUSSION 1951  
NWS STORM PREDICTION CENTER NORMAN OK  
1151 AM CDT FRI AUG 15 2025  
 
AREAS AFFECTED...NORTHERN/CENTRAL IA  
 
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE  
 
VALID 151651Z - 151845Z  
 
PROBABILITY OF WATCH ISSUANCE...60 PERCENT  
 
SUMMARY...THE SEVERE HAIL AND WIND THREAT MAY INCREASE THIS  
AFTERNOON ACROSS NORTHERN AND CENTRAL IOWA WITH LOW FORECAST  
CONFIDENCE ON BOTH COVERAGE/INTENSITY. A SEVERE THUNDERSTORM WATCH  
ISSUANCE IS POSSIBLE.  
 
DISCUSSION...AS ALLUDED TO IN THE 1630Z SWODY1, SHORT-TERM FORECAST  
CONFIDENCE IS LOW WITH REGARD TO A LONG-LIVED BUT SMALL CLUSTER OVER  
NORTHWEST IA. THIS HAD DIMINISHED FOR A TIME AFTER EARLIER SUPERCELL  
EVOLUTION IN NORTHEAST NE, BUT APPEARS TO BE OSCILLATING UP/DOWN  
AGAIN WITH SOME DEVELOPMENT FLANKING TO ITS SOUTHWEST. GRAVITY WAVES  
EMANATING FROM THIS CLUSTER AIDED IN ELEVATED CONVECTIVE DEVELOPMENT  
DOWNSTREAM IN WEST-CENTRAL IA WITH CLOUD BASES NEAR 10K FT. THESE  
UPDRAFTS APPEAR TO HAVE PULSED BACK DOWN AND MAY LACK  
SUSTAINABILITY.  
 
IN ADDITION TO THE WEAK LARGE-SCALE ASCENT, MODEST DEEP-LAYER SHEAR  
MAY LIMIT SUBSTANTIAL ORGANIZATION UNLESS A MORE PRONOUNCED COLD  
POOL DEVELOPS. THIS COULD OCCUR TOWARDS LATE AFTERNOON IF CONVECTIVE  
COVERAGE INDEED INCREASES SURROUNDING THE CONFINED CLUSTER. MORNING  
CAM GUIDANCE VARIES GREATLY FROM NIL CONVECTION IN THE HRRR TO AN  
ENLARGING CLUSTER AND MCS DEVELOPMENT. FOR NOW, THE MOST LIKELY  
SCENARIO IS FOR AN ISOLATED SEVERE HAIL/WIND THREAT BUT WITH A WIDE  
RANGE OF POTENTIAL SCENARIOS INTO THE LATE AFTERNOON.  
 
..GRAMS/MOSIER.. 08/15/2025  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT
 
 
ATTN...WFO...DVN...ARX...DMX...FSD...  
 
LAT...LON 42889553 43239518 43439437 43369245 43179192 42789181  
42419187 42009201 41639244 41589348 41789462 41999539  
42319569 42889553  
 
MOST PROBABLE PEAK WIND GUST...55-70 MPH  
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN  
 
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