The persistent cold arctic air mass combined with westerly winds to produce wind chill values of 40 below zero and lower to some northeast Montana locations near the international border with Canada.

Extreme Cold/Wind Chill in CENTRAL AND SOUTHERN VALLEY, MONTANA
From 02-MAR-19 02:07:00 to 02-MAR-19 06:47:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

With temperatures from -17 to -30 and winds speeds of 9 to 16 mph, wind chill values mainly in the -40s persisted for 2 to 4 hours during the early morning on the 2nd through portions of central Valley County. The coldest wind chill reading of -50 was recorded at 5:38 AM at the Saco US-2 DOT site.

Extreme Cold/Wind Chill in NORTHERN VALLEY, MONTANA
From 02-MAR-19 04:44:00 to 02-MAR-19 05:44:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: RAWS

With temperatures in the -20s and winds speeds of 12 to 18 mph, wind chill values of -48 to -50 occurred for about 1 hour during the early morning of the 2nd at the Bluff Creek RAWS site. The coldest wind chill reading of -50 was recorded at 5:44 AM.

Extreme Cold/Wind Chill in DANIELS, MONTANA
From 01-MAR-19 22:47:00 to 02-MAR-19 11:53:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

With temperatures in the -10s and -20s and wind speeds of 14 to 25 mph, wind chill values in the -40s and -50s persisted through the late night and overnight hours on the 1st and through the entire morning of the 2nd at the Navajo MT-5 DOT site.  The coldest wind chill reading of -53 was recorded from 6:42 AM to 7:02 AM.

Extreme Cold/Wind Chill in SHERIDAN, MONTANA
From 01-MAR-19 22:14:00 to 02-MAR-19 12:28:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

With temperatures in the -10s and -20s and wind speeds of 10 to 32 mph, wind chill values from -40 to -50 persisted through the late night and overnight hours on the 1st and into the noon hour on the 2nd across most of Sheridan County.  The coldest wind chill reading of -50 was recorded from 5:47 AM to 8:02 AM at the Comertown Turn-Off MT-5 DOT site.

Extreme Cold/Wind Chill in WESTERN ROOSEVELT, MONTANA
From 02-MAR-19 00:47:00 to 02-MAR-19 10:31:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

With temperatures in the -10s and -20s and wind speeds of 9 to 26 mph, wind chill values in the -40s  persisted through most of the morning on the 2nd. The coldest wind chill reading of -49 was recorded at 4:53 AM at the McDonalds MT-13 DOT site.

Extreme Cold/Wind Chill in MCCONE, MONTANA
From 02-MAR-19 06:05:00 to 02-MAR-19 08:50:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

With temperatures in the -10s and -20s and wind speeds of 9 to 15 mph, wind chill values in the -40s persisted for 2 to 3 hours on the morning of the 2nd across northern and central portions of McCone County. The coldest wind chill reading of -43 was recorded at 6:53 AM at the Cow Creek MT-13 DOT site.

Extreme Cold/Wind Chill in RICHLAND, MONTANA
From 02-MAR-19 05:04:00 to 02-MAR-19 11:54:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

With temperatures in the -10s and -20s and wind speeds of 11 to 20 mph, wind chill values in the -40s persisted through most of the morning on the 2nd at the Sioux Pass MT-16 DOT site. The coldest wind chill reading of -44 was recorded multiple times between 6:44 and 9:35 AM.

Extreme Cold/Wind Chill in DAWSON, MONTANA
From 02-MAR-19 05:44:00 to 02-MAR-19 11:16:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

With temperatures in the -10s and wind speeds of 15 to 29 mph, wind chill values in the -40s persisted through most of the morning on the 2nd at the Lindsay Divide MT-200 DOT site. The coldest wind chill reading of -49 was recorded at 8:05 AM.

Extreme Cold/Wind Chill in NORTHERN PHILLIPS, MONTANA
From 02-MAR-19 00:00:00 to 02-MAR-19 09:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

With no observation sites available in northern Phillips County, the Val Marie Southeast Saskatchewan ASOS site was used as a proxy. Temperatures in the -20s combined with wind speeds up to 13 mph to create wind chills values in the -40s.  The coldest wind chill reading of -48 was recorded at 5:00 AM MST.