Severe storms north and south; Metro in between; Cooler breezes Friday

A severe thunderstorm watch continues for southern Minnesota until 9pm tonight.

Image: NOAA SPC

Severe storms are also firing in north central Minnesota as strong storms rumble near Brainerd, Duluth and along the North Shore.

Image: WxUnderground

The storms contain hail, high winds and local downpours. Expect strong to possibly severe storms in northeast Minnesota and northwest Wisconsin this evening.

The storms have downed some trees in Crosslake and Deerwood.

DLH: Deerwood [Crow Wing Co, MN] trained spotter reports TSTM WND DMG at 05:26 PM CDT — small trees knocked down by winds. diameter of the trees size of a softball.

Here’s a radar shot of the storm as it crossed Lake Mille Lacs around 6pm this evening.

Image: WxUnderground

NOAA’s Storm Prediction Center is considering the possibility of a watch that may include parts of the northern metro tonight if the storms maintain their strength.

Image: NOAA SPC

Here’s the technical “mesoscale discussion” (weather geek speak) from NOAA.

MESOSCALE DISCUSSION 1519

NWS STORM PREDICTION CENTER NORMAN OK
0554 PM CDT THU JUL 25 2013

AREAS AFFECTED…E-CNTRL MN…NRN/CNTRL WI…PARTS OF THE UPPER
PENINSULA OF MI

CONCERNING…SEVERE POTENTIAL…WATCH POSSIBLE

PROBABILITY OF WATCH ISSUANCE…60 PERCENT

SUMMARY…THE LATEST ENVIRONMENTAL TRENDS SUGGEST THAT THE POTENTIAL FOR SVR STORMS THROUGH THE EVENING HOURS MAY BE SOMEWHAT GREATER THAN PREVIOUSLY ANTICIPATED. CONDITIONS ARE NOW BEING MONITORED FOR POSSIBLE WW ISSUANCE.

DISCUSSION…WATER VAPOR IMAGERY CONTINUES TO IMPACT A COMPACT VORT MAX ABOUT TO CROSS THE NRN MN BORDER. FORCING FOR ASCENT PRECEDING THIS FEATURE WILL LIKELY CONTINUE TO ENCOURAGE THUNDERSTORM DEVELOPMENT AHEAD OF A COLD FRONT APPROACHING FROM THE NW…AS ASCENT ACCOMPANYING A MODEST LOW-LEVEL JET STREAM SUPPORTS WARM-SECTOR THUNDERSTORM DEVELOPMENT. ALREADY…STORMS HAVE BEEN DEVELOPING IN THE WARM SECTOR IN W-CNTRL WI WHERE MID-LEVEL LAPSE RATES ARE MODESTLY STEEP…AND THIS ACTIVITY COULD INCREASE FURTHER
AS DEEP FORCING FOR ASCENT INCREASES. MEANWHILE…FRONTAL CONVECTION OVER NERN MN MAY CROSS PARTS OF NRN WI INTO THE EVENING. VERTICALLY VEERING WIND PROFILES WITH MODERATE MID-LEVEL FLOW PER AREA VWP DATA MAY SUPPORT A FEW ORGANIZED STORM STRUCTURES AND POSSIBLE SUPERCELLS. DMGG WINDS…SVR HAIL…AND POSSIBLY A TORNADO MAY OCCUR DESPITE LIMITED WARM-SECTOR BUOYANCY. TRENDS WILL BE MONITORED FOR POSSIBLE WW ISSUANCE.

Behind the front, cooler north winds will blow in the feeling of early fall.

Image: Twin Cities NWS