During the early evening hours of 18 August 2017, a potent severe storm with a history of producing very large hail and damaging wind gusts crossed from southwest MN into northwest IA. This activity was within a SPC slight risk for severe and a SPC severe thunderstorm watch. With the Iowa State Fair ongoing in Des Moines, WFO Des Moines requested a GOES-16 Meso Sector for DSS, beginning at 00z. The 1-min sector captured the tornado warned storm just as the sun set, providing a great depiction of the overshooting tops and anvil-top gravity waves. Further, smoke from Canadian fires is seen being drawn into the storm.
Figure 1: 18 August 2017 GOES-16 1-min VIS. Full res: https://satelliteliaisonblog.files.wordpress.com/2017/08/20170818_1min_vis_iowa.gif
-Bill Line, NWS
“The GOES-16 data posted on this page are preliminary, non-operational data and are undergoing testing. Users bear all responsibility for inspecting the data prior to use and for the manner in which the data are utilized.”
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