Widespread snow was observed across a large portion of southeast Wyoming on the 9th and 10th, with the heaviest snowfall generally observed to the north of a line from Laramie to Torrington. The highest totals in the lower elevations were observed across Carbon County with 12 to 13 inches of snow reported near Rawlins and Elk Mountain, as well as up to 18 inches around Saratoga in the Upper North Platte Basin. In the mountains, 2 to locally 3+ feet of snow were observed above 9000 feet elevation in the Snowys and Sierra Madres.

Heavy Snow in NIOBRARA COUNTY, WYOMING
From 09-DEC-21 14:00:00 to 10-DEC-21 15:00:00 (MST-7)
Reported by: Social Media

The public provided a photo via Facebook of approximately 11 inches of snow in Lusk. Archived radar and nearby surface observations indicate the heaviest snow likely fell late in the evening on the 9th.

Heavy Snow in GOSHEN COUNTY, WYOMING
From 09-DEC-21 15:00:00 to 10-DEC-21 17:00:00 (MST-7)
Reported by: COOP Observer

A COOP observer reported 7.5 inches of snow 10 miles north of Jay Em. Numerous additional reports of 2 to 5 inches were received across Goshen County.

Heavy Snow in CONVERSE COUNTY LOWER ELEVATIONS, WYOMING
From 09-DEC-21 14:00:00 to 10-DEC-21 15:00:00 (MST-7)
Reported by: Public

Multiple public and CoCoRaHS reports of 6 to 7 inches of snow in and around Douglas.

Heavy Snow in EAST PLATTE COUNTY, WYOMING
From 09-DEC-21 14:00:00 to 10-DEC-21 15:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Numerous public and CoCoRaHS reports of 6-8 inches across eastern Platte County. Highest amounts near Wheatland.

Heavy Snow in CENTRAL LARAMIE RANGE AND SOUTHWEST PLATTE COUNTY, WYOMING
From 09-DEC-21 14:00:00 to 10-DEC-21 15:00:00 (MST-7)
Reported by: Public

Multiple reports of 6-10 inches of snow from various sources. Facebook user submitted photo of 10 inches of snow 15 miles west of Wheatland at Midnight on 12/10.

Winter Storm in SOUTH LARAMIE RANGE, WYOMING
From 09-DEC-21 05:00:00 to 10-DEC-21 08:00:00 (MST-7)
Reported by: SNOTEL

An estimated storm total snowfall of 6 inches was reported at the Crow Creek SNOTEL using a snow water equivalent of 0.4 inches with a 15 to 1 ratio. Interstate 80 was briefly closed between Laramie and Cheyenne due to a vehicle accident.

Winter Weather in LARAMIE VALLEY, WYOMING
From 09-DEC-21 09:00:00 to 10-DEC-21 05:00:00 (MST-7)
Reported by: CoCoRaHS

Multiple COOP and CoCoRaHS observers reported between 2 and 4 inches of snow in and around the city of Laramie.

Heavy Snow in SHIRLEY BASIN, WYOMING
From 09-DEC-21 08:00:00 to 10-DEC-21 05:00:00 (MST-7)
Reported by: Trained Spotter

A trained spotter reported 5 to 8 inches of snow in Shirley Basin.

Heavy Snow in NORTH SNOWY RANGE FOOTHILLS, WYOMING
From 09-DEC-21 07:00:00 to 10-DEC-21 03:00:00 (MST-7)
Reported by: CoCoRaHS

A CoCoRaHS observer reported 13.3 inches of snow at Elk Mountain. Interstate 80 was closed at times due to vehicle accidents.

Heavy Snow in UPPER NORTH PLATTE RIVER BASIN, WYOMING
From 09-DEC-21 07:00:00 to 10-DEC-21 03:00:00 (MST-7)
Reported by: COOP Observer

Numerous reports of 12 to 18 inches of snow in the Upper North Platte River Basin near Saratoga from COOP and CoCoRaHS observers as well as the general public. Multiple photos received via social media.

Heavy Snow in SIERRA MADRE RANGE, WYOMING
From 08-DEC-21 21:00:00 to 10-DEC-21 12:00:00 (MST-7)
Reported by: SNOTEL

SNOTEL observations indicate an estimated 2 to 3 feet of snow fell in the Sierra Madres. Multiple sites reported 1.5 to 2.5 inches of liquid precipitation with snow ratios averaging 12 or 15 to 1 across the zone. The highest totals ranged from 35 to 40 inches above 9000 feet at Old Battle, Webber Springs, Little Snake River, and Blackhall Mountain.

Heavy Snow in FERRIS/SEMINOE/SHIRLEY MOUNTAINS, WYOMING
From 09-DEC-21 08:00:00 to 10-DEC-21 05:00:00 (MST-7)
Reported by: Mesonet

The 48-hour (interpolated) observed snowfall analysis from NOHRSC ending at 5 AM MST on 12/11 indicates pockets of 6-8 inches of snowfall over northern Carbon County, mainly in the higher terrain of the Ferris Mountains.

Heavy Snow in SNOWY RANGE, WYOMING
From 09-DEC-21 08:00:00 to 10-DEC-21 12:00:00 (MST-7)
Reported by: SNOTEL

SNOTEL observations indicate an estimated 1 to 2 feet of snow fell in the Snowy Range. Multiple sites reported 1.0 to 1.5 inches of liquid precipitation with snow ratios averaging 12 or 15 to 1 across the zone. The highest totals were above 10,000 feet elevation with around 21 inches at North French Creek and Medicine Bow.

Heavy Snow in CENTRAL CARBON COUNTY, WYOMING
From 09-DEC-21 07:00:00 to 10-DEC-21 03:00:00 (MST-7)
Reported by: COOP Observer

An NWS COOP observer reported 13 inches of snow 1 NNW of Rawlins. Multiple photos of 12+ inches received via social media.

Winter Weather in NORTH LARAMIE RANGE, WYOMING
From 09-DEC-21 14:00:00 to 10-DEC-21 15:00:00 (MST-7)
Reported by: Public

Multiple public reports of 6-10 inches in the foothills of the northern Laramie Range immediately along the eastern boundary of the zone.