Severe Storm Watch Posted Until 2 AM. Conditions are ripe for severe thunderstorms to push eastward from the Dakotas, tracking along a thermal gradient, supported by a rich supply of low-level moisture and sufficient wind shear for locally damaging winds at the surface. Details from NOAA SPC:
URGENT - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WATCH NUMBER 392 NWS STORM PREDICTION CENTER NORMAN OK 655 PM CDT SAT JUL 16 2016 THE NWS STORM PREDICTION CENTER HAS ISSUED A * SEVERE THUNDERSTORM WATCH FOR PORTIONS OF SOUTHWEST AND SOUTH CENTRAL MINNESOTA CENTRAL AND EASTERN SOUTH DAKOTA * EFFECTIVE THIS SATURDAY NIGHT AND SUNDAY MORNING FROM 655 PM UNTIL 200 AM CDT. * PRIMARY THREATS INCLUDE... SCATTERED DAMAGING WIND GUSTS TO 70 MPH LIKELY SCATTERED LARGE HAIL AND ISOLATED VERY LARGE HAIL EVENTS TO 2 INCHES IN DIAMETER POSSIBLE SUMMARY...SEVERE STORMS OVER WESTERN SOUTH DAKOTA ARE EXPECTED TO SPREAD EASTWARD TONIGHT INTO CENTRAL SD...WHILE NEW SEVERE STORMS ARE EXPECTED TO CONTINUE DEVELOPING OVER NORTH CENTRAL AND NORTHEAST SOUTH DAKOTA THIS EVENING. THIS ACTIVITY IS EXPECTED TO SPREAD SOUTHEASTWARD WITH TIME EVENTUALLY IMPACTING SOUTHEAST SOUTH DAKOTA AND PARTS OF SOUTHERN MINNESOTA. THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 60 STATUTE MILES NORTH AND SOUTH OF A LINE FROM 25 MILES NORTH NORTHWEST OF PIERRE SOUTH DAKOTA TO 45 MILES NORTH NORTHEAST OF FAIRMONT MINNESOTA. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU2). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES. AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM MOTION VECTOR 28030.
When It Rains - It Pours. Trite, but sadly true. The same areas that were drenched with another mega-rain event, a 1 in a thousand year flash flood up north last Monday into early Tuesday - may get soaked again overnight. NOAA's 4 KM NAM prints out an inch or two of rain for the MSP metro, with a band of over 4-5" setting up across central Minnesota, the Brainerd Lakes, into Crosby and Moose Lake, some of the same areas flooded earlier in the week. I hope the models are wrong.