Heavy Snow and Winter Weather in Montana, February 5 to 10, 2020

Name: Heavy Snow and Winter Weather in Montana, February 5 to 10, 2020
Start: 2020-02-05T08:20
End: 2020-02-10T07:00
Location: Montana

February 5 to 10, 2020 · NWS TFX · 14 events in 6 counties and zones

Satellite imagery reveals a long plume of moisture streaming over a broad eastern Pacific ridge, heading toward the northern Rockies. This moisture passes over the region.

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 14

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.

Satellite imagery reveals a long plume of moisture streaming over a broad eastern Pacific ridge, heading toward the northern Rockies. This moisture passes over the region. A strong northwesterly flow, results in a prolonged period of heavy mountain snowfall for the Central and Southwest Mountains. Mountain snowfall occurs over the Big Belts, Bridger and Madison ranges; this expands in coverage and intensity overnight. One to three feet of new snow expected. There are some nuances to address for lower elevation impacts. As the upper level jet noses over the Northern Rockies, there will be some warming as the ridge drifts further east. Short term model|guidance supports a period of more widespread snow developing in association with this warm front. Thus, expect a trace to a few inches of snow accumulation for the southwest valleys. With rising snow levels and a break in precipitation Thursday afternoon, melting occurs on these interstate corridors. Thus, snowfall totals are below warning criteria, but note that icing could occur Thursday night with additional new snowfall enhancing the icing hazard. NBM temperatures appear to be biased a few degrees too warm for the southwest valleys, so blended towards the lower side of guidance. Following this possible break in snowfall rates, the next embedded shortwave moves through Thursday night into early Friday. This produces a period of moderate to heavy snowfall. Snow expands into portion of North-central Montana as a cold front trails behind this wave.

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 Feb 5, 4:40 AM MST, 3 hours 40 minutes earlier.

Area forecast discussion, Feb 5, 4:40 AM MST, 3 hours 40 minutes before

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Event by event

8 heavy snow, 6 winter weather. Local standard time, as filed.

Heavy Snow, Gallatin

When: February 5, 8:20 AM MST to February 6, 8:20 AM MST
Where: Gallatin forecast zone
Reported by: Public

Reported 26 inches new snow last 24 hours. 14 inches new overnight. ski area web report. 12 nne Bozeman.

Heavy Snow, Gallatin

When: February 5, 11:00 PM MST to February 6, 11:00 AM MST
Where: Gallatin forecast zone
Reported by: Official NWS Observations

Measured 6.7 inches of new snow in the past 12 hours at the Bozeman Airport. 1 NE Belgrade.

Winter Weather, Madison

When: February 6, 5:00 AM MST
Where: Madison forecast zone
Reported by: Trained Spotter

Measured 8 inches of new snow fell overnight near Big Sky. currently still snowing, 3/4 mile visibility, and calm winds.

Heavy Snow, Madison

When: February 6, 5:00 AM MST to February 7, 5:00 AM MST
Where: Madison forecast zone
Reported by: Public

Reported 5 inches last 12 hours. 11 inches last 24 hours. 21 inches last 48 hours. Ski resort web report. 5 wnw Big Sky.

Heavy Snow, Gallatin

When: February 6, 5:30 AM MST to February 7, 5:30 AM MST
Where: Gallatin forecast zone
Reported by: Public

Reported 24 inches last 24 hours. 3 inches new overnight. ski resort web report. 12 nne Bozeman.

Heavy Snow, Beaverhead

When: February 6, 6:53 AM MST to February 7, 6:53 AM MST
Where: Beaverhead forecast zone
Reported by: Public

Reported 11 inches last 24 hrs. 1 inch new overnight. 12 storm total. ski area web report. 7 sse Neihart.

Winter Weather, Beaverhead

When: February 6, 7:00 AM MST to February 7, 7:00 AM MST
Where: Beaverhead forecast zone
Reported by: CoCoRaHS

Cocorahs station mt-bv-18 3 nne Polaris cocorahs. The duration of the snow event was 24 hours.

Winter Weather, Judith Basin

When: February 6, 7:30 AM MST
Where: Judith Basin forecast zone
Reported by: Trained Spotter

Measured 4 inches new snow overnight. Hobson.

Heavy Snow, Gallatin

When: February 6, 8:00 AM MST
Where: Gallatin forecast zone
Reported by: COOP Observer

Co-op observer station 11 inches bgsm8 Big Sky 2 wnw.

Winter Weather, Meagher

When: February 6, 8:06 AM MST
Where: Meagher forecast zone
Reported by: Public

Reported 7 inches new snow at ski resort. web report. 7 sse Neihart.

Heavy Snow, Madison

When: February 6, 8:17 AM MST
Where: Madison forecast zone
Reported by: Public

Reported 10 inches new snow overnight 6 w Big Sky.

Winter Weather, Broadwater

When: February 6, 5:00 PM MST
Where: Broadwater forecast zone
Reported by: COOP Observer

Co-op observer station towm8, townsend coop. two-day total.

Heavy Snow, Gallatin

When: February 7, 8:00 AM MST
Where: Gallatin forecast zone
Reported by: COOP Observer

Co-op observer station bgsm8, Big Sky 2 wnw. 48-hour snow total.

Winter Weather, Gallatin

When: February 9, 7:00 AM MST to February 10, 7:00 AM MST
Where: Gallatin forecast zone
Reported by: Public

Reported 24-hour snow report from Bridger Bowl ski area. 12 ne Bozeman.

What these are

Heavy Snow: Snowfall reaching the local warning threshold without the other hazards of a winter storm.
Winter Weather: Snow, sleet or freezing rain below warning levels that still caused disruption, damage or casualties.

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

The same day elsewhere

Every storm in Montana in 2020 Every state in 2020 This day in weather history Warnings in Montana, February 2020

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 2026-10-01. Each event’s entry at NCEI: 874814, 874823, 874834, 874843, 874840, 874844, 874846, 874838, 874816, 874837, 874818, 874826, 874841, 874847.