153
ACUS11 KWNS 231730
SWOMCD
SPC MCD 231729
WIZ000-MIZ000-IAZ000-MNZ000-232000-
MESOSCALE DISCUSSION 1416
NWS STORM PREDICTION CENTER NORMAN OK
1229 PM CDT MON JUN 23 2025
AREAS AFFECTED...PARTS OF NORTHEASTERN IOWA THROUGH CENTRAL AND
NORTHEASTERN WISCONSIN
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 231729Z - 232000Z
PROBABILITY OF WATCH ISSUANCE...60 PERCENT
SUMMARY...GRADUALLY INTENSIFYING THUNDERSTORM ACTIVITY MAY POSE
INCREASING POTENTIAL FOR A FEW STRONG DOWNBURSTS THROUGH 3-5 PM CDT.
DISCUSSION...DESTABILIZATION, WITHIN A PRE-FRONTAL BOUNDARY-LAYER
CHARACTERIZED BY SEASONABLY HIGH MOISTURE CONTENT (INCLUDING SURFACE
DEW POINTS IN EXCESS OF 70F), IS SUPPORTING A GRADUAL INCREASE IN
CONVECTIVE DEVELOPMENT, PARTICULARLY WITHIN A SMALL CLUSTER NEAR LA
CROSS WI. THIS IS OCCURRING AS INSOLATION CONTRIBUTES TO EROSION OF
A RELATIVELY WARM CAPPING LAYER BASED AROUND 700 MB, PERHAPS AIDED
BY FORCING FOR ASCENT ASSOCIATED WITH ONE OR TWO SUB-SYNOPTIC
MID/UPPER PERTURBATIONS MIGRATING AROUND THE NORTHWESTERN PERIPHERY
OF THE PROMINENT MID-LEVEL HIGH CENTERED NEAR THE SOUTHERN
APPALACHIANS.
WITH CONTINUING BOUNDARY-LAYER WARMING AND WEAKENING OF INHIBITION,
A FURTHER INCREASE IN THUNDERSTORM DEVELOPMENT SEEMS LIKELY TO
GRADUALLY CONTINUE DURING THE NEXT FEW HOURS. UPDRAFT INFLOW
CHARACTERIZED BY CAPE IN EXCESS OF 2000 J/KG, IN THE PRESENCE OF
MODESTLY SHEARED WEST-SOUTHWESTERLY DEEP-LAYER MEAN FLOW, WEAKENING,
BUT STILL IN EXCESS OF 30 KT, MAY SLOWLY CONTRIBUTE TO INCREASING
INTENSITY AND ORGANIZATION. ALTHOUGH THE DEVELOPMENT OF ANY
APPRECIABLE CONVECTIVELY GENERATED SURFACE COLD POOL WILL PROBABLY
BE SLOW DUE THE MOIST NATURE OF THE LOW-LEVEL LEVELS, AND MODEST
LAPSE RATES, PRECIPITATION LOADING IN STRONGER CONVECTION MAY
INCREASINGLY POSE THE RISK FOR A FEW STRONG DOWNBURSTS THROUGH
20-22Z.
..KERR/THOMPSON.. 06/23/2025
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT
ATTN...WFO...MQT...GRB...MKX...DVN...ARX...DMX...
LAT...LON 43519239 44889036 45658874 45018674 44138837 43379009
42459249 42699322 43519239
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
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