This loop of rapid scan (5 to 15 minute interval) GOES-10 10.7 micron IR imagery shows the development of supercell convection across southwestern Minnesota from 20:00 to 21:50 UTC. Counties reporting tornadoes are outlined in black (from left to right: Nobles, Cottonwood, and Brown counties). Note the pronounced warm wake/enhanced-V cloud top signature with the convective system just northwest of Nobles county starting at 20:55 UTC. This cloud top signature was first evident at 21:15 using GOES-8 15-minute imagery (no 21:00 GOES-8 image was available due to operational schedules). The first tornado in northwestern Nobles county Minnesota was reported around 21:23 UTC.