Winter Storm in Montana, December 19 to 20, 2010

Name: Winter Storm in Montana, December 19 to 20, 2010
Start: 2010-12-19T19:00
End: 2010-12-20T12:00
Location: Montana

December 19 to 20, 2010 · NWS TFX · 4 events in 4 counties and zones

Pacific moisture moved over a cold airmass east of the continental divide and produced areas of heavy snow. Snowfall amounts up to a foot were reported.

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 4

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.

What happened

The episode as NWS TFX wrote it up.

Pacific moisture moved over a cold airmass east of the continental divide and produced areas of heavy snow. Snowfall amounts up to a foot were reported.

What forecasters said that day

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 Great Falls, MT wrote its last area forecast discussion before the first event at Dec 19, 5:00 PM MST, 2 hours earlier.

Area forecast discussion, Dec 19, 5:00 PM MST, 2 hours before

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Hazardous weather outlook, Dec 19, 3:14 PM MST, 3 hours 46 minutes before

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In the hours before

Local storm report, Dec 19, 6:42 PM MST, 18 minutes before

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Event by event

4 winter storm. Local standard time, as filed.

Winter Storm, Cascade

When: December 19, 7:00 PM MST to December 20, 10:20 AM MST
Where: Cascade forecast zone
Reported by: Public

Seven inches of snow fell at Belt 7E.

Winter Storm, Judith Basin

When: December 19, 7:00 PM MST to December 20, 10:20 AM MST
Where: Judith Basin forecast zone
Reported by: Public

Six inches of snow fell at Moccasin 1W.

Winter Storm, Fergus

When: December 19, 7:00 PM MST to December 20, 12:00 PM MST
Where: Fergus forecast zone
Reported by: COOP Observer

Six inches of snow fell at Grass Range.

Winter Storm, Meagher

When: December 19, 7:00 PM MST to December 20, 10:20 AM MST
Where: Meagher forecast zone
Reported by: COOP Observer

Twelve inches of snow fell at Neihart 21W.

What these are

Winter Storm: A storm that brought snow, sleet or freezing rain at warning levels, usually over several hours or days.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Montana in 2010 Every state in 2010 This day in weather history Warnings in Montana, December 2010

Sources

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: 267632, 267634, 267636, 267640.