A cold front dropped across Wyoming. The combination of a tight pressure gradient and strong mid level winds mixing to the surface brought high winds to many areas.
Every event with a place to put it; 8 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS RIW wrote it up.
A cold front dropped across Wyoming. The combination of a tight pressure gradient and strong mid level winds mixing to the surface brought high winds to many areas. The highest gusts were in the higher elevations where hurricane force gusts were reported in the Absarokas, Wind River Range and the Green Mountains. In the lower elevations, gusts over 58 mph were reported in portions of Johnson, Natrona, Fremont, Sweetwater and Sublette Counties, with the highest gusts including 65 mph at Hiland, Wyoming and 67 mph east of Wamsutter, Wyoming, along Interstate 80.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Riverton, WY wrote its last area forecast discussion before the first event at Oct 13, 4:49 PM MST, 2 hours 47 minutes earlier.
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</html>The national radar mosaic for the moment the first event began.
8 high wind. Local standard time, as filed.
There were numerous reports of high winds in Natrona County, Wyoming. Some notable gusts included 65 mph at Hiland, Wyoming and 62 mph along Hat Six Road.
The Camp Creek RAWS recorded a maximum wind gust of 83 mph.
The Wind River RAWS site had a maximum wind gust of 84 mph.
The wind sensor along the Chief Joseph Highway had sustained winds over 50 mph for two hours with a maximum wind gust of 78 mph.
A 58 mph wind gust was reported at the airport at Big Piney, Wyoming.
There were numerous high wind gusts along Interstate 80. Some notable gusts included 67 mph at Continental Divide and 62 mph at Bitter Creek.
A wind gust of 59 mph was reported at the Riverton, Wyoming airport.
The WYDOT weather sensor at Indian Creek along Interstate 90 recorded a maximum wind gust of 64 mph.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wyoming in 2020Every state in 2020This day in weather historyWarnings in Wyoming, October 2020
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-10-01. Each event’s entry at NCEI: 922592, 922591, 922589, 922588, 922596, 922594, 922595, 922590.