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This loop of GOES-8 10.7 micron IR imagery shows the development of supercell convection across southern Minnesota into central Wisconsin. Counties reporting tornadoes are outlined in black. Note the pronounced warm wake/enhanced-V cloud top signature with the convective system over southwestern Minnesota (after 21:15 UTC), and also in southeastern Minnesota (after 22:02 UTC). The first tornado was reported around 21:23 UTC in Nobles county (the farthest southwest of the outlined counties).