Very strong winds aloft, as a result of a powerful jet stream, mixed down to the surface during the early morning hours of the 31st. These winds continued for many areas through the afternoon hours of February 1st.
Every event with a place to put it; 4 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 BYZ wrote it up.
Very strong winds aloft, as a result of a powerful jet stream, mixed down to the surface during the early morning hours of the 31st. These winds continued for many areas through the afternoon hours of February 1st.
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 Billings, MT wrote its last area forecast discussion before the first event at Jan 30, 8:24 PM MST, 7 hours 1 minute earlier.
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</html>The national radar mosaic for the moment the first event began.
4 high wind. Local standard time, as filed.
Winds gusted between 58 and 64 mph across the area.
Winds gusted to 58 mph across the area.
Winds gusted to 59 mph across the area.
A wind gust of 76 mph was recorded at the Livingston airport.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2020Every state in 2020This day in weather historyWarnings in Montana, January 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 2026-09-30. Each event’s entry at NCEI: 871260, 871259, 871261, 871262.