Montana, 2017

Winter Storm and Heavy Snow in Montana, November 1, 2017

November 1, 2017 · NWS TFX · 7 events in 7 counties and zones

A clipper low pressure system dropped southwards from Alberta and into eastern Montana. With sufficient cold air in place, showers developed with dropping snow levels causing a change over to all snow in the morning hours.

The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
7

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.

A clipper low pressure system dropped southwards from Alberta and into eastern Montana. With sufficient cold air in place, showers developed with dropping snow levels causing a change over to all snow in the morning hours.

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 Nov 1, 4:35 AM MST, 2 hours 25 minutes earlier.

Area forecast discussion, Nov 1, 4:35 AM MST, 2 hours 25 minutes before
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In the hours before

Special weather statement, Nov 1, 3:08 AM MST, 3 hours 52 minutes before
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Event by event

4 heavy snow, 3 winter storm. Local standard time, as filed.

Winter Storm, Meagher

When
November 1, 7:00 AM MST
Where
Meagher forecast zone
Reported by
SNOTEL

Boulder Mountain Snotel 24 hour snowfall total of 11 inches.

Winter Storm, Judith Basin

When
November 1, 8:00 AM MST
Where
Judith Basin forecast zone
Reported by
SNOTEL

Spur Park Snotel 24 hour snowfall total of 8 inches.

Winter Storm, Fergus

When
November 1, 8:00 AM MST
Where
Fergus forecast zone
Reported by
SNOTEL

Crystal Lake Snotel 24 hour snowfall total of 8 inches.

Heavy Snow, Gallatin

When
November 1, 9:20 AM MST
Where
Gallatin forecast zone
Reported by
Social Media

MDOT reported an over sized load blocking driving lane along I-90 11 miles east of Bozeman.

Heavy Snow, Cascade

When
November 1, 6:30 PM MST
Where
Cascade forecast zone
Reported by
Social Media

Great Falls Tribune reported over social media that Warden Bridge (10th Ave S.) is really icy, traffic has slowed after wrecks.

Heavy Snow, Southern Lewis and Clark

When
November 1, 6:50 PM MST
Where
Southern Lewis and Clark forecast zone
Reported by
Social Media

Social media report of dangerous driving conditions near MacDonald Pass via MDOT.

Heavy Snow, North Rocky Mountain Front

When
November 1, 7:50 PM MST
Where
North Rocky Mountain Front forecast zone
Reported by
Social Media

MDOT reported severe driving conditions along US-89 from St. Mary to the Canadian line.

What these are

Winter Storm
A storm that brought snow, sleet or freezing rain at warning levels, usually over several hours or days.
Heavy Snow
Snowfall reaching the local warning threshold without the other hazards of a winter storm.

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

The same day elsewhere

More

Every storm in Montana in 2017Every state in 2017This day in weather historyWarnings in Montana, November 2017

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: 725485, 725490, 725491, 725854, 725855, 725852, 725853.