Strong tornadoes possible today!
A potent jet streak is currently passing over the Northern Plains, with a warm front extending from southeastern SD into southern MN, setting the stage for explosive supercell development over this area by peak heating. The latest RUC is showing 0-1 km EHIs of 7-8 along the warm front by 00z, which is likely a little over-estimated but still more than conducive for strong tornadoes. CAPE values of 5000+ over this area as very high dewpoints pool along the boundary will result in intense updrafts and massive hail in persistent supercells. All models are showing relatively early convective initiation by 20-21z, given the weak capping inversion, with elevated convection already marching through southeast SD toward the reservoir of strong instability. The HRRR is showing multiple supercells along the warm
front in southern MN by 00z, gradually morphing into a derecho and surging southeastward toward the Great Lakes Region. The SPC has already issued a tornado watch from southeast SD into southern MN, with the discussion mentioning an elevated supercell currently just east of Huron, SD that is expected to become surface-based with a significant tornado threat developing as it tracks along the warm front into southern MN. The greatest tornado threat will be between 21 and 00z as the low-level jet increases, but before the storms merge into an MCS. I wouldn't be surprised there are over a dozen tornado reports this afternoon into evening... TVN already has several live streaming teams in the field, so be sure to check out the Live Video page throughout the day!
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