Upper Midwest bracing for severe weather outbreak!
An active weather day is expected over eastern North and South Dakota, Minnesota and Iowa as a powerful storm system continues to make its way across the northern Plains. Atmospheric dynamics -- including very strong wind shear and moderate to high instability -- will be supportive of intense thunderstorm development throughout the afternoon and into the late evening, with the threat initially coming in the form of supercells over the Red River Valley early this afternoon. Strong tornadoes and very large hail will be a possibility with these discrete storms; eventually the storm mode is expected to transition into a more linear event, with damaging winds likely to impact central and southern Minnesota into northern Iowa later this evening. Tornadoes and very large hail will still be a concern even after the system "lines out," if it does in fact do as much -- there is a chance that storms could continue as discrete or semi-discrete, which would increase the tornado threat substantially.
Models are definitely trending toward a more linear event later in the evening, so the greatest emphasis is being placed on a widespread damaging wind event, given the scope of the area that could potentially be impacted. Multiple chasers will be streaming today on the
Live page, so be sure to check it out for a real-time look at what's happening. And, as always, residents of these areas are strongly encouraged to be prepared for severe weather and remain aware of rapidly changing weather conditions!
http://www.tornadovideos.net/component/content/article/36-tornadoes/1235-upper-midwest-bracing-for-severe-weather-outbreak
