Montana, 2021

Cold in Montana, February 5 to 15, 2021

February 5 to 15, 2021 · NWS GGW · 14 events in 14 counties and zones

A very cold arctic air mass from the north strengthened and spread over the region. It's persistence and often clear skies, along with even a little bit of wind led to dangerous wind chill values across most of northeast Montana for more than a week.

Where it happened

Every event with a place to put it; 14 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

  • Tornadoes
  • Tropical storms and surge
  • Floods
  • Wind
  • Hail
  • Winter weather
  • Heat and drought
  • Cold
  • Fire, smoke and dust
  • Marine and coastal
  • Other

Open the live radar over this ground

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 GGW wrote it up.

A very cold arctic air mass from the north strengthened and spread over the region. It's persistence and often clear skies, along with even a little bit of wind led to dangerous wind chill values across most of northeast Montana for more than a week.

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 Glasgow, MT wrote its last area forecast discussion before the first event at Feb 5, 2:10 PM MST, 7 hours 17 minutes earlier.

Area forecast discussion, Feb 5, 2:10 PM MST, 7 hours 17 minutes before
Area Forecast Discussion
National Weather Service Glasgow MT
210 PM MST Fri Feb 5 2021

.DISCUSSION...
Not too many changes were made to going forecast. All the Wind
Chill and Winter Weather Advisories look good.

A couple pushes of moisture/snow move in with the first one this
evening. Glasgow area looks to pick up a quick half-inch early
this evening while heavier amounts can be expected over the SW
zones.

The next push comes in late Saturday, but it looks like upslope
areas of central Montana cashes in with the SW zones only picking
up about 2 to around 4 inches.

Cold Canadian Arctic high pressure then sinks in from NW Canada
early next week while low pressure near the Great Lakes becomes
occluded/vertically stacked and retrogrades into central Canada.
This will keep us locked in a cold pattern through next week with
highs 10 below to 10 above with the coldest night coming Monday
Night. Wind chills by Tuesday morning may be widespread 40 to 45 below
across the northern zones and a Wind Chill Warning may be needed.

Some relief is on the horizon though as the upper low weakens and
the upper pattern begins to bring in milder Pacific air. We just
have to get through next week. TFJ

&&

.AVIATION...
Brief but sudden lowering conditions to IFR are expected at KGGW
early this evening with snow and low clouds. KOLF, KSDY and KGDV
should just lower to MVFR for a few hours tonight.

Low VFR conditions return Saturday with MVFR conditions possibly returning
Sunday morning.

Winds: North 5-15 kts tonight becoming light then East Saturday.
TFJ

&&

.GLASGOW WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 11 AM MST Sunday for Petroleum.

Wind Chill Advisory from 6 PM this evening to 11 AM MST Sunday
for Central and Southeast Phillips...Central and Southern
Valley...Dawson...Garfield...McCone...Northern Phillips...
Prairie...Richland...Southwest Phillips...Wibaux.

Wind Chill Advisory until 11 AM MST Sunday for Daniels...Eastern
Roosevelt...Northern Valley...Sheridan...Western Roosevelt.

&&

weather.gov/glasgow

The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

14 cold/wind chill. Local standard time, as filed.

Cold/Wind Chill, Sheridan

When
February 5, 9:27 PM MST to February 14, 7:46 AM MST
Where
Sheridan forecast zone
Reported by
Department of Highways
Coordinates
48.721, -104.505 (the zone’s center; the record gives no point)

For multiple sites across Sheridan County, temperatures in the teens and 20s below zero and breezy winds created wind chills of -40 or worse beginning as early as the night of the 5th and lasting as long as the early morning of the 14th. The peak wind chill of -55 was recorded from 1:13 AM to 1:23 AM on the 12th at the Comertown Turn-OFF MT-5 DOT site (MTCOM).

Cold/Wind Chill, Daniels

When
February 5, 10:01 PM MST to February 14, 4:46 AM MST
Where
Daniels forecast zone
Reported by
Department of Highways
Coordinates
48.784, -105.549 (the zone’s center; the record gives no point)

At the Navajo MT-5 DOT site (MTRED), temperatures in the teens and 20s below zero and breezy winds created wind chills of -40 or worse from the night of the 5th into the early morning of the 14th. The peak wind chill of -53 was recorded from 12:01 AM to 1:34 AM on the 12th.

Cold/Wind Chill, Western Roosevelt

When
February 6, 12:01 AM MST to February 14, 7:37 AM MST
Where
Western Roosevelt forecast zone
Reported by
Department of Highways
Coordinates
48.295, -105.016 (the zone’s center; the record gives no point)

For multiple sites across western Roosevelt County, temperatures in the teens and 20s below zero and breezy winds created wind chills of -40 or worse beginning as early as the early morning of the 6th and lasting as long as the early morning of the 14th. The peak wind chill of -52 was recorded at 3:46 AM on the 12th at the McDonalds MT-13 DOT site (MTMCD).

Cold/Wind Chill, Eastern Roosevelt

When
February 6, 12:44 AM MST to 6:55 PM MST
Where
Eastern Roosevelt forecast zone
Reported by
Mesonet
Coordinates
48.295, -105.016 (the zone’s center; the record gives no point)

For multiple sites across eastern Roosevelt County, temperatures below -20 and breezy winds created wind chills of at least -40 or worse beginning in the early morning of the 6th and lasting into the evening of the 13th. The peak wind chill of -49 was recorded from 4:55 AM to 5:10 AM on the 12th at the Culbertson airport mesonet site.

Cold/Wind Chill, Richland

When
February 6, 1:54 AM MST to February 14, 7:56 AM MST
Where
Richland forecast zone
Reported by
Department of Highways
Coordinates
47.788, -104.561 (the zone’s center; the record gives no point)

For multiple sites across Richland County, temperatures below -20 and breezy winds created wind chills of at least -40 or worse beginning as early as the early morning of the 6th and lasting as late as the morning of the 14th. The peak wind chill of -51 was recorded both at 3:54 AM and 6:55 AM on the 12th at the Sioux Pass MT-16 DOT site (MTSOO).

Cold/Wind Chill, McCone

When
February 6, 5:59 AM MST to February 14, 8:40 AM MST
Where
McCone forecast zone
Reported by
Mesonet
Coordinates
47.645, -105.795 (the zone’s center; the record gives no point)

For multiple sites across McCone County, although initially in a more isolated way, temperatures below -20 and breezy winds created wind chills of at least -40 or worse beginning as early as the morning of the 6th and lasting as late as the morning of the 14th. The peak wind chill of -62 was recorded at 4:55 AM on the 14th at the Circle Town County Airport mesonet site (K4U6).

Cold/Wind Chill, Central and Southern Valley

When
February 7, 9:10 PM MST to February 14, 6:53 AM MST
Where
Central and Southern Valley forecast zone
Reported by
Department of Highways
Coordinates
48.365, -106.667 (the zone’s center; the record gives no point)

For multiple sites across central and southern Valley County, temperatures in the teens and 20s below zero and breezy winds created wind chills of -40 or worse beginning as early as the night of the 7th and lasting as long as the early morning of the 14th. The peak wind chill of -52 was recorded at 2:26 AM on the 14th at the Saco US-2 DOT site (MTSCO).

Cold/Wind Chill, Northern Valley

When
February 7, 9:44 PM MST to February 14, 7:44 AM MST
Where
Northern Valley forecast zone
Reported by
RAWS
Coordinates
48.365, -106.667 (the zone’s center; the record gives no point)

At the Bluff Creek RAWS site (BLUM8), temperatures in the teens and 20s below zero and breezy winds created wind chills of -40 or worse from the night of the 7th into the early morning of the 14th. The peak wind chill of -56 was recorded at 6:44 AM on the 13th.

Cold/Wind Chill, Dawson

When
February 8, 6:56 AM MST to February 15, 4:19 AM MST
Where
Dawson forecast zone
Reported by
Department of Highways
Coordinates
47.266, -104.899 (the zone’s center; the record gives no point)

For multiple sites across Dawson County, although initially in a more isolated way, temperatures below -20 and breezy winds created wind chills of at least -40 or worse beginning as early as the morning of the 8th and lasting as late as the early morning of the 15th. The peak wind chill of -54 was recorded from 5:39 AM to 7:25 AM on the 12th at the Lindsay Divide MT-200 DOT site (MTLND).

Cold/Wind Chill, Wibaux

When
February 8, 10:47 PM MST to February 14, 7:35 AM MST
Where
Wibaux forecast zone
Reported by
Department of Highways
Coordinates
46.965, -104.249 (the zone’s center; the record gives no point)

At the Beaver Hill I-94 DOT site (MTBVR), temperatures below -20 and breezy winds created wind chills of at least -40 or worse from the night of the 8th into the morning of the 14th. The peak wind chill of -51 was recorded from 4:33 AM to 6:33 AM on the 12th.

Cold/Wind Chill, Prairie

When
February 9, 2:08 AM MST to February 14, 4:15 AM MST
Where
Prairie forecast zone
Reported by
RAWS
Coordinates
46.861, -105.378 (the zone’s center; the record gives no point)

For multiple sites across Prairie County, temperatures below -20 and breezy winds created wind chills of at least -40 or worse beginning in the early morning of the 9th and lasting into the early morning of the 14th. The peak wind chill of -49 was recorded from 2:08 AM to 3:08 AM on the 12th at the Big Sheep Mountain RAWS site (LCFM8).

Cold/Wind Chill, Garfield

When
February 9, 7:37 PM MST to February 14, 6:48 PM MST
Where
Garfield forecast zone
Reported by
ASOS
Coordinates
47.278, -106.993 (the zone’s center; the record gives no point)

For multiple sites across Garfield County, temperatures in the teens and 20s below zero and breezy winds created wind chills of -40 or worse beginning as early as the evening of the 9th and lasting as long as the evening of the 14th. The peak wind chill of -54 was recorded at 6:48 PM on the 14th at the Jordan airport ASOS site (KJDN).

Cold/Wind Chill, Central and Se Phillips

When
February 10, 12:15 AM MST to February 14, 8:35 AM MST
Where
Central and Se Phillips forecast zone
Reported by
AWOS
Coordinates
48.259, -107.913 (the zone’s center; the record gives no point)

At the Malta airport AWOS site (KM75), although conditions were not quite as bad during the daytime, night-time temperatures below -20 and breezy winds created wind chills of at least -40 or worse each night from the morning of the 8th through the morning of the 14th. The peak wind chill of -50 was recorded at 1:15 AM on the 12th.

Cold/Wind Chill, Little Rocky Mountains

When
February 10, 6:23 AM MST to February 14, 8:11 AM MST
Where
Little Rocky Mountains forecast zone
Reported by
Department of Highways
Coordinates
48.259, -107.913 (the zone’s center; the record gives no point)

At the Malta South US-191 DOT site (MTMAL), temperatures in the teens and 20s below zero and breezy winds created wind chills of -40 or worse from the morning of the 10th into the morning of the 14th. The peak wind chill of -49 was recorded at 1:54 AM on the 11th.

What these are

Cold/Wind Chill
Cold or wind chill below warning criteria that caused deaths, injuries or damage.

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

The same day elsewhere

More

Every storm in Montana in 2021Every state in 2021This day in weather historyWarnings in Montana, February 2021

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: 942356, 942355, 942357, 942361, 942362, 942358, 942354, 942340, 942359, 942363, 942360, 942339, 942335, 942336.