125
ACUS11 KWNS 120257
SWOMCD
SPC MCD 120257
ILZ000-IAZ000-MOZ000-120500-
MESOSCALE DISCUSSION 1934
NWS STORM PREDICTION CENTER NORMAN OK
0957 PM CDT MON AUG 11 2025
AREAS AFFECTED...FAR NORTHERN MISSOURI INTO SOUTHEAST IOWA
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 120257Z - 120500Z
PROBABILITY OF WATCH ISSUANCE...5 PERCENT
SUMMARY...A PAIR OF SUPERCELLS THAT HAS DEVELOPED OVER SOUTHEAST
IOWA MAY POSE A BRIEF TORNADO AND ISOLATED HAIL RISK OVER THE NEXT
COUPLE OF HOURS. ADDITIONAL SUPERCELL DEVELOPMENT IS POSSIBLE, BUT
THE OVERALL SEVERE THREAT IS EXPECTED TO REMAIN LIMITED SPATIALLY
AND TEMPORALLY.
DISCUSSION...OVER THE PAST HOUR, A PAIR OF SUPERCELLS HAS DEVELOPED
ACROSS SOUTHEAST IA IN THE VICINITY OF A DECAYING MCV EMANATING OUT
OF NORTHERN MO. THIS ACTIVITY IS ON THE NORTHERN FRINGE OF AN AXIS
OF WARM LOW-LEVEL CONDITIONS/WEAKLY INHIBITED MLCAPE AND IS ON THE
PERIPHERY OF A SWATH OF 30-35 KNOT MID-LEVEL WINDS ASSOCIATED WITH
THE MCV. BASED ON RECENT MESOANALYSIS ESTIMATES, THIS SPATIAL WINDOW
OF FAVORABLE MLCAPE AND ADEQUATE DEEP-LAYER WIND SHEAR APPEARS
RELATIVELY SMALL WITH WEAKER CAPE/GREATER INHIBITION WITH NORTHWARD
EXTENT AND WEAKER SHEAR WITH SOUTHWARD EXTENT. HOWEVER, THESE CELLS
MAY LINGER WITHIN THIS WINDOW FOR THE NEXT COUPLE OF HOURS. WHILE
SOME LOW-LEVEL VEERING IS NOTED VIA SURFACE OBSERVATIONS AND RECENT
UPPER-AIR ANALYSES/FORECAST SOUNDINGS, WEAK WIND MAGNITUDES ARE
LIMITING OVERALL SRH (ONLY AROUND 50-100 M2/S2 EFFECTIVE SRH). THIS
CASTS UNCERTAINTY ON THE OVERALL TORNADO POTENTIAL. NONETHELESS, THE
VELOCITY SIGNATURES ASSOCIATED WITH THE SUPERCELLS SUGGEST ORGANIZED
MESOCYCLONES ARE PRESENT AND SOME BRIEF TORNADO AND HAIL THREAT MAY
MANIFEST WITH THESE STORMS PRIOR TO STRONGER NOCTURNAL LOW-LEVEL
STABILIZATION LATER THIS EVENING. AN ADDITIONAL SUPERCELL OR TWO MAY
DEVELOP WITHIN A WEAK WARM ADVECTION REGIME ACROSS FAR NORTHERN
MO/SOUTHEAST IA, BUT OVERALL COVERAGE OF THE SEVERE THREAT IS
EXPECTED TO BE LIMITED IN THE ABSENCE OF STRONGER FORCING FOR ASCENT
AND INCREASING INHIBITION WITH TIME.
..MOORE/HART.. 08/12/2025
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT
ATTN...WFO...DVN...DMX...EAX...
LAT...LON 41429072 41049083 40719118 40499162 40349207 40329254
40289289 40299324 40379339 40589347 40799342 41019317
41269275 41489233 41689160 41749118 41659083 41429072
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
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