A moist southwest flow aloft combined with a strong disturbance brought winter storm conditions to portions of Southern Montana and Northern Wyoming. Heavy snow developed over the mountains before spreading onto the plains.
Every event with a place to put it; 3 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.
A moist southwest flow aloft combined with a strong disturbance brought winter storm conditions to portions of Southern Montana and Northern Wyoming. Heavy snow developed over the mountains before spreading onto the plains.
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 Nov 17, 3:15 AM MST, 5 hours 45 minutes earlier.
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</html>The national radar mosaic for the moment the first event began.
4 winter storm. Local standard time, as filed.
Fisher Creek Snotel reported 16 inches of new snow.
Snowfall of 8 inches was reported about 7 miles ESE of Fort Smith and 17 miles WSW of Wyola.
The Red Lodge area received 6 inches of snow.
Areas near Lame Deer received 8 inches of snow.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2011Every state in 2011This day in weather historyWarnings in Montana, November 2011
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 2026-09-24. Each event’s entry at NCEI: 351594, 351596, 351595, 351597.