Strong mid-October low brought heavy snow, strong winds, and blizzard conditions to southeast Wyoming. Areas west of the Laramie Range received 4 to 10 inches of snowfall with areas in the Snowy and Sierra Madres mountains receiving higher amounts. Precipitation remained light across Laramie County with around an inch of snowfall, but wind gusts approached 65 MPH. Farther north, heavier snowfall was observed with around 10 inches of snowfall mixed with strong winds resulting in whiteout blizzard conditions, especially in Converse and Niobrara Counties. Interstate 25 north of Wheatland was closed for around 12 hours due to winter conditions.

Blizzard in EAST PLATTE COUNTY, WYOMING
From 12-OCT-21 23:54:00 to 13-OCT-21 03:14:00 (MST-7)
Reported by: Department of Highways

WYDOT mesonet station WY1 Coleman along Interstate 25 measured 50 to 60 MPH wind gusts and one quarter mile visibility for over 3 hours. Interstate 25 between Wheatland and Douglas was closed for almost 12 hours. CoCoRaHS observers reported between 2 and 10 inches of snowfall.

High Wind in EAST PLATTE COUNTY, WYOMING
From 12-OCT-21 23:52:00 to 13-OCT-21 04:08:00 (MST-7)
Magnitude: 56.00 MG
Reported by: Department of Highways

WYDOT mesonet station WY1 Coleman along Interstate 25 between Wheatland and Glendo measured maximum wind gust.

High Wind in GOSHEN COUNTY, WYOMING
From 13-OCT-21 04:22:00 to 13-OCT-21 07:02:00 (MST-7)
Magnitude: 53.00 MG
Reported by: ASOS

Torrington Airport ASOS station KTOR measured maximum wind gust. Union Pacific Railroad station BRAUN1 - UP075 also reported high winds.

High Wind in CENTRAL LARAMIE RANGE AND SOUTHWEST PLATTE COUNTY, WYOMING
From 13-OCT-21 06:00:00 to 13-OCT-21 12:00:00 (MST-7)
Magnitude: 52.00 EG
Reported by: Department of Highways

Strong winds estimated at WYDOT station Bordeaux KBRX along Interstate 25 between Chugwater and Wheatland.

High Wind in SOUTH LARAMIE RANGE FOOTHILLS, WYOMING
From 13-OCT-21 06:26:00 to 13-OCT-21 08:02:00 (MST-7)
Magnitude: 58.00 MG
Reported by: Mesonet

Union Pacific Railroad mesonet station EMKAYW UP226 measured maximum wind gust. WYDOT mesonet station Otto WY38 along Interstate 80 also reported high winds.

High Wind in CENTRAL LARAMIE COUNTY, WYOMING
From 13-OCT-21 06:30:00 to 13-OCT-21 13:18:00 (MST-7)
Magnitude: 56.00 MG
Reported by: Department of Highways

WYDOT mesonet station Bear Creek WY40 along Interstate 25 between Cheyenne and Chugwater measured maximum wind gust.

High Wind in EAST LARAMIE COUNTY, WYOMING
From 13-OCT-21 10:13:00 to 13-OCT-21 10:13:00 (MST-7)
Magnitude: 55.00 MG
Reported by: Mesonet

Union Pacific Railroad mesonet station LNDBRG UR343 measured maximum wind gust.

Winter Weather in UPPER NORTH PLATTE RIVER BASIN, WYOMING
From 12-OCT-21 15:15:00 to 12-OCT-21 21:00:00 (MST-7)
Reported by: CoCoRaHS

Snow accumulation of 4 to 5 inches reported around Saratoga. CoCoRaHS observer in Saratoga measured 5 inches of snow accumulation.

Winter Weather in LARAMIE VALLEY, WYOMING
From 12-OCT-21 14:25:00 to 13-OCT-21 01:50:00 (MST-7)
Reported by: CoCoRaHS

Snow accumulation of 4 to 5 inches reported around Laramie. CoCoRaHS observer measured 5.3 inches of snow accumulation 2.5 miles east-southeast of Laramie.

Winter Storm in NORTH SNOWY RANGE FOOTHILLS, WYOMING
From 12-OCT-21 15:30:00 to 13-OCT-21 10:30:00 (MST-7)
Reported by: CoCoRaHS

Snow accumulation of 7 to 10 inches reported in the area with strong winds. CoCoRaHS observer 2 miles south of Elk Mountain measured 10.8 inches of snow accumulation. WYDOT mesonet stations measured wind gusts 40 to 60 MPH for over 6 consecutive hours. Interstate 80 between Laramie and Rawlins was closed for over 24 hours.

Winter Storm in SOUTH LARAMIE RANGE, WYOMING
From 12-OCT-21 12:00:00 to 13-OCT-21 10:30:00 (MST-7)
Reported by: SNOTEL

Estimated 6 inches of snow accumulation at Crow Creek SNOTEL site (8330 feet elevation) with 0.4 inches of snow water equivalent and 15:1 snow ratios. WYDOT and UPR mesonet stations measured wind gusts 50 to 70 MPH for over 12 consecutive hours. Interstate 80 between Laramie and Cheyenne was closed for over 14 hours.

Heavy Snow in FERRIS/SEMINOE/SHIRLEY MOUNTAINS, WYOMING
From 12-OCT-21 00:00:00 to 13-OCT-21 05:00:00 (MST-7)
Reported by: Public

Estimated snowfall totals around 8 inches near Muddy Gap.

Heavy Snow in SHIRLEY BASIN, WYOMING
From 12-OCT-21 00:00:00 to 13-OCT-21 05:00:00 (MST-7)
Reported by: Public

Estimated snowfall totals around 8 inches near Shirley Basin.

Heavy Snow in SIERRA MADRE RANGE, WYOMING
From 12-OCT-21 00:00:00 to 13-OCT-21 09:00:00 (MST-7)
Reported by: SNOTEL

Estimated 15 inches of snow accumulation at Blackhall Mountain SNOTEL site (9820 feet elevation) with 1.0 inches of snow water equivalent and 15:1 snow ratios.

Heavy Snow in NORTH LARAMIE RANGE, WYOMING
From 12-OCT-21 00:00:00 to 13-OCT-21 09:00:00 (MST-7)
Reported by: SNOTEL

Estimated 12 inches of snow accumulation at Windy Peak SNOTEL site (7900 feet elevation) with 0.8 inches of snow water equivalent and 15:1 snow ratios.

Heavy Snow in SNOWY RANGE, WYOMING
From 12-OCT-21 05:00:00 to 13-OCT-21 09:00:00 (MST-7)
Reported by: SNOTEL

Estimated 13.6 inches of snow accumulation at Sand Lake SNOTEL site (10050 feet elevation) with 0.8 inches of snow water equivalent and 17:1 snow ratios.

Heavy Snow in CENTRAL CARBON COUNTY, WYOMING
From 12-OCT-21 06:00:00 to 13-OCT-21 05:35:00 (MST-7)
Reported by: SNOTEL

Estimated 6 inches of snow accumulation at Sage Creek Basin SNOTEL site (7850 feet elevation) with 0.5 inches of snow water equivalent and 12:1 snow ratios. CoCoRaHS observer near Sinclair also reported 5.5 inches of snow accumulation.

Blizzard in NIOBRARA COUNTY, WYOMING
From 13-OCT-21 01:22:00 to 13-OCT-21 08:30:00 (MST-7)
Reported by: Department of Highways

WYDOT mesonet station US20 - Van Tassell (WY60) measured wind gusts 35-45 MPH with whiteout conditions per local highway webcams. Public reported snow accumulations of 11 inches in Lusk.

Blizzard in CENTRAL LARAMIE RANGE AND SOUTHWEST PLATTE COUNTY, WYOMING
From 13-OCT-21 00:34:00 to 13-OCT-21 03:56:00 (MST-7)
Reported by: Department of Highways

WYDOT mesonet station Bordeaux (KBRX) along Interstate 25 reported one-quarter mile visibility and strong winds in falling and blowing snow 9 miles south of Wheatland.

Blizzard in CONVERSE COUNTY LOWER ELEVATIONS, WYOMING
From 12-OCT-21 23:15:00 to 13-OCT-21 02:15:00 (MST-7)
Reported by: ASOS

ASOS station KDGW - Douglas Airport measured wind gusts 40 to 50 MPH and one quarter mile visibility for 3 hour period. Interstate 25 between Douglas and Casper was closed for over 15 hours. Public reported 12 inches of snow accumulation in Douglas and 11 inches in Glenrock.