Montana, 2020

High Wind and Strong Wind in Montana, November 13 to 15, 2020

November 13 to 15, 2020 · NWS TFX · 13 events in 7 counties and zones

A Pacific trough and associated strong flow aloft brought strong surface winds to much of North-central and Southwest Montana on November 13th and 14th 2020. Surface winds strengthened well ahead of the approaching system as a tight pressure gradient developed between lee side troughing over the Canadian prairies and high pressure over Eastern Idaho and Wyoming.

The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
13

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 Pacific trough and associated strong flow aloft brought strong surface winds to much of North-central and Southwest Montana on November 13th and 14th 2020. Surface winds strengthened well ahead of the approaching system as a tight pressure gradient developed between lee side troughing over the Canadian prairies and high pressure over Eastern Idaho and Wyoming. Once the trough axis passed, cold air advection helped bring the 50 to 70 kt H700 winds to the surface.

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 12, 4:40 PM MST, 9 hours 9 minutes earlier.

Area forecast discussion, Nov 12, 4:40 PM MST, 9 hours 9 minutes before
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Event by event

12 high wind, 1 strong wind. Local standard time, as filed.

High Wind, Cascade

When
November 13, 1:49 AM MST
Where
Cascade forecast zone
Measured
56 kt (64 mph) measured gust
Reported by
Mesonet

Jeffrey station (5 SSE Stockett) measured a 56 kt (65 mph) non-thunderstorm wind gust.

High Wind, North Rocky Mountain Front

When
November 13, 3:07 AM MST
Where
North Rocky Mountain Front forecast zone
Measured
55 kt (63 mph) measured gust
Reported by
Mesonet

MDT station at Two Medicine Bridge measured a 55 kt (63 mph) non-thunderstorm wind gust.

High Wind, Southern Rocky Mountain Front

When
November 13, 4:54 AM MST
Where
Southern Rocky Mountain Front forecast zone
Measured
52 kt (60 mph) measured gust
Reported by
Mesonet

Miller Colony station (4 SSE Bynum) measured a 52 kt (60 mph) non-thunderstorm wind gust.

High Wind, North Rocky Mountain Front

When
November 13, 9:34 AM MST
Where
North Rocky Mountain Front forecast zone
Measured
56 kt (64 mph) measured gust
Reported by
Mesonet

Upper Elk Creek station (14 SW Augusta) measured a 56 kt (65 mph) non-thunderstorm wind gust.

High Wind, Madison

When
November 13, 9:42 AM MST
Where
Madison forecast zone
Measured
50 kt (58 mph) measured gust
Reported by
Department of Highways

MDT Norris Hill station measured a 50 kt (58 mph) non-thunderstorm wind gust.

High Wind, Madison

When
November 13, 9:42 AM MST
Where
Madison forecast zone
Measured
53 kt (61 mph) measured gust
Reported by
AWOS

Ennis big Sky Airport measured a 53 kt (61 mph) non-thunderstorm wind gust.

High Wind, North Rocky Mountain Front

When
November 13, 12:22 PM MST
Where
North Rocky Mountain Front forecast zone
Measured
51 kt (59 mph) measured gust
Reported by
Department of Highways

MDT station at Two Medicine Bridge measured a 51 kt (59 mph) non-thunderstorm wind gust.

High Wind, Meagher

When
November 13, 2:40 PM MST
Where
Meagher forecast zone
Measured
54 kt (62 mph) measured gust
Reported by
Mesonet

White Sulphur Springs station (4 S White Sulphur Springs) measured a 54 kt (62 mph) non-thunderstorm wind gust.

High Wind, Southern Lewis and Clark

When
November 14, 6:13 AM MST
Where
Southern Lewis and Clark forecast zone
Measured
54 kt (62 mph) measured gust
Reported by
Department of Highways

MDT Sieben station measured a 54 kt (62 mph) non-thunderstorm wind gust.

High Wind, Meagher

When
November 14, 7:25 AM MST
Where
Meagher forecast zone
Measured
53 kt (61 mph) measured gust
Reported by
AWOS

White Sulphur Springs Airport measured a 53 kt (61 mph) non-thunderstorm wind gust.

High Wind, Southern Lewis and Clark

When
November 14, 7:56 AM MST
Where
Southern Lewis and Clark forecast zone
Measured
50 kt (58 mph) measured gust
Reported by
Department of Highways

MDT MacDonald Pass station measured a 50 kt (58 mph) non-thunderstorm wind gust.

High Wind, Fergus

When
November 14, 3:15 PM MST
Where
Fergus forecast zone
Measured
56 kt (64 mph) measured gust
Reported by
AWOS

N Bar Ranch station (13 SSW Forestgrove) measured a 56 kt (64 mph) non-thunderstorm wind gust.

Strong Wind, Cascade

When
November 15, 3:00 PM MST
Where
Cascade forecast zone
Measured
47 kt (54 mph) estimated gust
Reported by
Public

A visibly diseased pine fell onto a house during estimated 47 kt (54 mph) non thunderstorm wind gust.

What these are

High Wind
Sustained non-thunderstorm winds of 40 mph or more for an hour, or gusts of 58 mph or more.
Strong Wind
Non-thunderstorm winds below high wind criteria that nonetheless caused damage or casualties.

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

The same day elsewhere

More

Every storm in Montana in 2020Every state in 2020This day in weather historyWarnings in Montana, November 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: 927065, 927067, 927066, 927071, 927073, 927074, 927075, 927076, 927077, 927078, 927079, 927345, 927346.