Extreme Cold/Wind Chill, Southern Lewis and Clark
- When
- February 4, 9:27 AM MST
- Where
- Southern Lewis and Clark forecast zone
- Reported by
- Department of Highways
MacDonald Pass MT DOT station reported wind chill of -49F with sustained wind of 17 mph.
Extreme Cold in Montana, February 4, 2019
During the morning of February 4th, an Arctic high pressure ridge was present over Montana, especially east of the Continental Divide. A tight surface pressure gradient along the western flank of this ridge yielded breezy winds at MacDonald Pass.
The toll
- Deaths
- 0
- Injuries
- 0
- Property damage
- None recorded
- Crop damage
- None recorded
- Events
- 1
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.
During the morning of February 4th, an Arctic high pressure ridge was present over Montana, especially east of the Continental Divide. A tight surface pressure gradient along the western flank of this ridge yielded breezy winds at MacDonald Pass. The combination of these winds and frigid air led to extreme wind chills at the pass.
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 3, 4:55 PM MST, 16 hours 32 minutes earlier.
Area forecast discussion, Feb 3, 4:55 PM MST, 16 hours 32 minutes before
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</html>Event by event
1 extreme cold/wind chill. Local standard time, as filed.
What these are
- Extreme Cold/Wind Chill
- Temperatures or wind chills at or below the local warning criteria, or cold that caused deaths.
After NWS Directive 10-1605, the rules offices file Storm Data by.
The same day elsewhere
- Flash Flood and Winter Storm in California, February 4 to 6, 2019
- Ice Storm and Winter Storm in Michigan, February 4, 2019
- Winter Storm and Hail in California, February 4 to 5, 2019
- Flooding and Heavy Snow in California, February 4 to 14, 2019
- Flooding in New York, February 4 to 6, 2019
- Heavy Snow in Washington, February 4, 2019
- Ice Storm in Wisconsin, February 4, 2019
- Avalanche and Heavy Snow in Arizona, February 4 to 6, 2019
- Ice Storm in Wisconsin, February 4 to 5, 2019
- Flooding in Wisconsin, February 4 to 5, 2019
- Ice Storm in Michigan, February 4, 2019
- Waterspout in Eastern Pacific Coastal Waters, February 4, 2019
More
Every storm in Montana in 2019Every state in 2019This day in weather historyWarnings in Montana, February 2019
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: 803910.