Northerly flow following the passage of an Arctic cold front brought brutally cold temperatures and dangerous wind chills to much of western and central Wyoming. The Daniel cooperative observer recorded a low temperature of -48F on the morning of Wednesday, December 31. In addition, many locations across Fremont, Hot Springs, Lincoln, Sweetwater, and Washakie counties saw temperatures of -30F to -35F. Wind chill temperatures of -30F were common, as well, especially in a swath from southern Lincoln County, east through Sweetwater County, and on into Natrona County.

Cold/Wind Chill in STAR VALLEY, WYOMING
From 31-DEC-14 00:00:00 to 31-DEC-14 12:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Low temperatures at Afton and Etna were -33F and -30F, respectively, on Wednesday morning, December 31.

Cold/Wind Chill in NATRONA COUNTY LOWER ELEVATIONS, WYOMING
From 30-DEC-14 00:00:00 to 31-DEC-14 13:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

The wind chill across Natrona County, including at the Casper-Natrona County International Airport, fell below -30F for much of Tuesday, December 30, and the morning of December 31. The coldest wind chills occurred the evening of December 30.

Cold/Wind Chill in CASPER MOUNTAIN, WYOMING
From 30-DEC-14 00:00:00 to 31-DEC-14 12:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Wind chill readings of -30F to -35F occurred on Casper Mountain, primarily on Tuesday, December 30.

Cold/Wind Chill in UPPER GREEN RIVER BASIN FOOTHILLS, WYOMING
From 31-DEC-14 00:00:00 to 31-DEC-14 12:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

The cooperative observer at the Daniel Fish Hatchery had a low temperature of -48F on the morning of Wednesday, December 31. The observer also reported 18 inches of snow on the ground. Other very cold temperatures included -42F at Bondurant and -35F at Boulder.

Cold/Wind Chill in UPPER GREEN RIVER BASIN, WYOMING
From 31-DEC-14 00:00:00 to 31-DEC-14 13:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

The airport in Big Piney had a low temperature of -35F on Wednesday morning, December 31.

Cold/Wind Chill in EAST SWEETWATER COUNTY, WYOMING
From 30-DEC-14 00:00:00 to 31-DEC-14 12:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Wind chill readings at the Rock Springs-Sweetwater County Airport fell as low as -38F early Wednesday morning, December 31.

Cold/Wind Chill in SOUTHEAST BIG HORN BASIN, WYOMING
From 31-DEC-14 00:00:00 to 31-DEC-14 12:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

The ASOS at the Worland Municipal Airport had a low temperature of -31F on the morning of Wednesday, December 31. In addition, a cooperative observer near Big Trails in southeast Washakie County recorded an overnight low of -34F.

Cold/Wind Chill in GREEN MOUNTAINS & RATTLESNAKE RANGE, WYOMING
From 30-DEC-14 00:00:00 to 31-DEC-14 12:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Low temperatures around Jeffrey City City were -33F to -37F. In addition, wind chill temperatures below -30F were recorded through the day on Tuesday, December 30, and the morning of December 31.

Cold/Wind Chill in WIND RIVER BASIN, WYOMING
From 31-DEC-14 00:00:00 to 31-DEC-14 12:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Low temperatures in Riverton ranged from -30F to -36F.

Cold/Wind Chill in SOUTHWEST BIG HORN BASIN, WYOMING
From 31-DEC-14 00:00:00 to 31-DEC-14 12:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

The cooperative observer near Lucerne recorded an overnight low of -38F on Wednesday morning, December 31. The same location had 20 inches of snow on the ground.

Cold/Wind Chill in SOUTH LINCOLN COUNTY, WYOMING
From 30-DEC-14 00:00:00 to 31-DEC-14 12:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

A mesonet sensor near Kemmerer registered a low temperature of -30F on Wednesday morning, December 31. In addition, wind chill temperatures as cold as -43F were recorded.