...THERE IS A MDT RISK OF SVR TSTMS THIS AFTERNOON FOR ERN ND AND NW MN... ...THERE IS A SLGT RISK OF SVR TSTMS THROUGH TONIGHT FOR THE NRN PLAINS/UPPER MS VALLEY/UPPER GREAT LAKES... ...THERE IS A SLGT RISK OF SVR TSTMS TONIGHT FOR NRN NEW ENGLAND/NY... ...NRN PLAINS/UPPER MS VALLEY THROUGH TONIGHT... A REMNANT CLUSTER OF STORMS FROM EARLY THIS MORNING HAS RECENTLY SHOWN SIGNS OF INTENSIFICATION NEAR MINOT ND. THIS CLUSTER IS ASSOCIATED WITH A SHORTWAVE TROUGH MOVING ACROSS NE MT/NW ND...AROUND THE NW PERIPHERY OF THE CENTRAL PLAINS MIDLEVEL HIGH. AT THE SURFACE...A REMNANT BOUNDARY PERSISTS FROM CENTRAL/ERN ND INTO NRN MN...WHILE A REINFORCING FRONTAL SURGE IS MOVING SEWD INTO NE ND/NW MN IN ASSOCIATION WITH A SEPARATE SHORTWAVE TROUGH APPROACHING NW ONTARIO. VERY RICH MOISTURE /BOUNDARY LAYER DEWPOINTS OF 75-80 F/ IS PRESENT ALONG AND S OF THIS BOUNDARY...WHERE ADDITIONAL DAYTIME HEATING WILL COMBINE WITH STEEP MIDLEVEL LAPSE RATES TO RESULT IN EXTREME INSTABILITY THIS AFTERNOON /MLCAPE OF 5000-6000 J PER KG/ AND A WEAKENING CAP. THE THERMODYNAMIC ENVIRONMENT SUPPORTS INTENSIFICATION OF THE ONGOING STORMS IN ND...WITH THE EXTREME INSTABILITY AND 50+ KT EFFECTIVE BULK SHEAR FAVORABLE FOR EMBEDDED SUPERCELLS WITH VERY LARGE HAIL. UPSCALE GROWTH OF THE CLUSTER APPEARS PROBABLE INTO THE AFTERNOON...WHEN COLD POOL DEVELOPMENT AND FORWARD PROPAGATION ALONG THE SURFACE BOUNDARY COULD LEAD TO BOW ECHO FORMATION WITH AN ATTENDANT RISK FOR WIDESPREAD/SIGNIFICANT WIND DAMAGE. THERE WILL ALSO BE SOME RISK FOR TORNADOES WITH THE MORE DISCRETE SUPERCELLS IN THE CLUSTER BY EARLY AFTERNOON...AS THE BOUNDARY LAYER DESTABILIZES AND THE CONVECTION BECOMES SOLIDLY ROOTED AT THE SURFACE. IF THE SCENARIO EVOLVES AS EXPECTED INTO THE AFTERNOON...THE MDT RISK AREA MAY NEED TO BE EXPANDED FARTHER SE INTO MORE OF MN...AND POSSIBLY EVEN NW WI FOR LATE THIS AFTERNOON/EVENING.
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