837
ACUS11 KWNS 282324
SWOMCD
SPC MCD 282323
WIZ000-MNZ000-290200-
MESOSCALE DISCUSSION 0278
NWS STORM PREDICTION CENTER NORMAN OK
0623 PM CDT FRI MAR 28 2025
AREAS AFFECTED...FAR SOUTHEAST MINNESOTA AND NORTHERN/CENTRAL
WISCONSIN
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 282323Z - 290200Z
PROBABILITY OF WATCH ISSUANCE...5 PERCENT
SUMMARY...A COUPLE INSTANCES OF MARGINALLY SEVERE HAIL (AROUND 1
INCH) ARE POSSIBLE THROUGH AROUND 03Z.
DISCUSSION...THE LATEST RADAR AND IR SATELLITE IMAGERY SHOW A
GRADUAL INCREASE IN ASCENT ALONG/IMMEDIATELY NORTH OF A WARM FRONT
DRAPED ACROSS PORTIONS OF CENTRAL WI -- AHEAD OF A WEAK SURFACE LOW
OVER SOUTHEAST MN. THIS IS ASSOCIATED WITH GRADUALLY STRENGTHENING
WARM ADVECTION IN THE VICINITY OF A COUPLED UPPER-LEVEL JET
STRUCTURE. A STEEP MIDLEVEL LAPSE RATE PLUME EXTENDING EASTWARD INTO
THE AREA (SEE EARLIER 12Z UPSTREAM SOUNDINGS) IS CONTRIBUTING TO
AROUND 1000 J/KG MUCAPE, WHICH MAY INCREASE TO AROUND 1500 J/KG AS
ASCENT MOISTENS THE BASE OF THE EML. THIS INSTABILITY AND AROUND
40-50 KT OF CLOUD-LAYER SHEAR (PER REGIONAL VWP DATA) MAY PROMOTE A
COUPLE LOOSELY ORGANIZED SUPERCELL STRUCTURES CAPABLE OF PRODUCING
HAIL TO AROUND 1 INCH IN DIAMETER. WHILE THE MAJORITY OF THIS
ACTIVITY IS EXPECTED TO REMAIN ELEVATED, A COUPLE ONGOING CELLS IN
SOUTHEAST MN INTO WEST-CENTRAL WI ARE EVOLVING WITHIN OR SLIGHTLY ON
THE WARM SIDE OF THE BAROCLINIC ZONE. EVEN SO, ISOLATED SEVERE HAIL
SHOULD STILL BE THE PRIMARY HAZARD.
THE SEVERE-HAIL RISK SHOULD GENERALLY PERSIST THROUGH AROUND 03Z,
BEFORE CELLULAR CONVECTION IS EXPECTED TO DIMINISH AMID WEAKENING
INSTABILITY/MIDLEVEL LAPSE RATES.
..WEINMAN/MOSIER.. 03/28/2025
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT
ATTN...WFO...GRB...DLH...ARX...MPX...
LAT...LON 44018942 43939152 43919237 43989285 44499320 44919312
45349273 45549210 45589125 45368815 44958768 44458783
44098819 44018942
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
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