After a long period without any severe weather, the atmosphere appears primed for a potentially dangerous severe weather outbreak tomorrow across areas from Kansas to Minnesota. Some areas could see tornadoes, baseball-size hail, and winds in excess of 75 MPH.
Enhanced instability and favorable wind shear through the atmosphere will allow for supercells to form across parts of the central Plains and Midwest during the afternoon hours on Sunday. In anticipation of some of the supercells growing quite strong, the Storm Prediction Center has about two million people between southeastern Nebraska and extreme southern Minnesota — including Omaha, Lincoln, and Sioux City — under the highest threat for "significant severe weather."
Significant severe weather includes the risk for hail larger than golf balls, thunderstorm wind gusts greater than 75 MPH, and/or tornadoes that could produce EF-2 or greater damage. The most likely hazards would be extremely large hail and damaging winds, although the SPC's latest discussion notes that the environment could be favorable for the development of "isolated strong tornadoes" in the highest risk area.
The agency's next forecast for tomorrow will be issued at 1:00AM CDT, complete with a fuller breakdown of the exact threat for different modes of severe weather. Remember that a 30% chance of severe weather is very different from a 30% chance of rain. Keep an eye on your local National Weather Service office and local media for any watches or warnings that result from the potential outbreak.
[Map by the author]