6 PM This Evening. NOAA's 3 km HRRR model shows a fairly impressive line of storms from near Brainerd and Crosby into the Twin Cities and Mankato by late afternoon and evening, capable of heavy rain, small hail and wind gusts to 60 mph. A Severe Storm Watch may have to be issued by SPC.


Possible Severe Storm Watch Issuance. Parts of southern Minnesota, southwest Wisconsin and northern Iowa are being monitored for a possible Severe Storm Watch. Details from NOAA SPC:

 AREAS AFFECTED...PORTIONS OF SOUTHERN MINNESOTA...NORTHERN IOWA...AND EXTREME WEST-CENTRAL WISCONSIN CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE VALID 281812Z - 282015Z PROBABILITY OF WATCH ISSUANCE...40 PERCENT SUMMARY...THUNDERSTORMS WILL CONTINUE TO INCREASE IN COVERAGE AND INTENSITY THROUGH THE AFTERNOON. LARGE HAIL AND LOCALIZED DAMAGING WIND WILL BE THE MAIN THREATS. THE AREA IS BEING MONITORED FOR A POSSIBLE WATCH ISSUANCE. DISCUSSION...THUNDERSTORMS ARE DEVELOPING IN A ZONE OF CONVERGENCE ARCING FROM NORTHEAST NORTH DAKOTA SOUTHEASTWARD INTO WEST-CENTRAL MINNESOTA SOUTHWARD INTO NORTH-CENTRAL IOWA. THESE THUNDERSTORMS ARE EXPECTED TO INCREASE IN COVERAGE THROUGH THE AFTERNOON AS LARGE-SCALE ASCENT INCREASES WITH THE APPROACH OF THE NEGATIVELY TILTED SHORT-WAVE TROUGH. RECENT SPC MESOANALYSIS DATA SUGGESTS INSTABILITY IS INCREASING ACROSS THE AREA...ESPECIALLY DOWNSTREAM FROM THE DEVELOPING CONVECTION...WHERE MLCAPE VALUES ARE NOW BETWEEN 1000-1500 J/KG DESPITE THE PRESENCE OF WIDESPREAD CLOUD COVER. CURRENTLY DEEP-LAYER SHEAR IS BETWEEN 40 AND 50 KNOTS IN THE VICINITY OF THE ONGOING/DEVELOPING CONVECTION AND DROPS OFF MARKEDLY TO THE EAST. HOWEVER...DEEP-LAYER SHEAR IS EXPECTED TO INCREASE DOWNSTREAM OF THE TROUGH /WHERE THE GREATEST INSTABILITY CURRENTLY RESIDES/ AS A 50 KNOT MID-LEVEL SPEED MAX CONTINUES TO OVERSPREAD THE AREA. THUS AS THUNDERSTORMS MOVE EAST INTO THE STRONGER INSTABILITY...AND DEEP-LAYER SHEAR INCREASES...A GRADUAL INCREASE IN THUNDERSTORM INTENSITY IS EXPECTED. DESPITE THE APPROACHING MID-LEVEL SPEED MAX...MID-LEVEL FLOW SHOULD REMAIN PARALLEL TO THE LOW-LEVEL CONVERGENCE ZONE. THIS WILL TEND TO FAVOR A MORE LINEAR MODE TO THE CONVECTION. GIVEN THE EXPECTED LINEAR CONVECTIVE MODE...AN ISOLATED LARGE HAIL AND LOCALIZED DAMAGING WIND THREAT WILL BE THE MAIN THREAT WITH THE STRONGEST STORMS.

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Weekend Severe Risk Peaks Sunday Evening - Minnesota on Track for Statewide June Rainfall Record

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Severe Storm Watch until 9 PM - Includes Twin Cities Metro