An arctic front dropped southward across Wyoming and brought in an unusually cold air mass. The result was many records were broken. The locations that saw monthly record low temperatures broken included Casper, Riverton and Lander, Wyoming. The coldest temperatures occurred in the morning of October 30th. The most impressive was at Big Piney, Wyoming, where a combination of a clear sky, fresh snow cover and light winds resulted in a low of minus 26, which broke the record by 29 degrees. Note: All low temperatures in events occurred in the morning of October 30th.

Cold/Wind Chill in NORTHEAST JOHNSON COUNTY, WYOMING
From 28-OCT-19 00:00:00 to 30-OCT-19 23:59:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Many locations in northeastern Johnson County fell below zero, including minus 15 to the southeast of Story, Wyoming. At the Buffalo, Wyoming airport, a low of three degrees below zero was recorded, setting a new all time record low for the month of October.

Cold/Wind Chill in SOUTHEAST JOHNSON COUNTY, WYOMING
From 28-OCT-19 00:00:00 to 30-OCT-19 23:59:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Temperatures below zero were common across southern Johnson County. The lowest temperatures recorded was minus 9 at Linch, Wyoming on the morning of October 30th.

Extreme Cold/Wind Chill in SOUTH LINCOLN COUNTY, WYOMING
From 28-OCT-19 00:00:00 to 30-OCT-19 23:59:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Extremely cold temperatures occurred in southern Lincoln County. Some of the coldest temperatures on the morning of the 30th included minus 26 at Fossil Butte National Monument and minus 20 just to the west of Kemmerer, Wyoming.

Extreme Cold/Wind Chill in STAR VALLEY, WYOMING
From 28-OCT-19 00:00:00 to 30-OCT-19 23:59:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Very cold temperatures occurred in the Star Valley. Some of the coldest temperatures included minus 11 at the Afton, Wyoming airport and minus 9 at Thayne, Wyoming.

Avalanche in NATRONA COUNTY LOWER ELEVATIONS, WYOMING
From 28-OCT-19 00:00:00 to 30-OCT-19 23:59:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Very cold temperatures occurred through much of Natrona County. Some of the coldest temperatures included minus 20 west of Alcova, Wyoming and minus 15 at Evansville, Wyoming. At the Casper, Wyoming airport, the low of minus 9 on the morning of October 30th was the coldest temperatures ever recorded at the Casper, Wyoming airport, breaking the old record of minus 3 set in 1971.

Extreme Cold/Wind Chill in CODY FOOTHILLS, WYOMING
From 28-OCT-19 00:00:00 to 30-OCT-19 23:59:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Very cold temperatures occurred throughout the Cody Foothills. Some of the coldest temperatures included minus 9 near Meeteetse, Wyoming and minus 4 in Cody, Wyoming.

Extreme Cold/Wind Chill in SOUTHEAST BIG HORN BASIN, WYOMING
From 28-OCT-19 00:00:00 to 30-OCT-19 23:59:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

There were widespread temperatures below zero in Washakie County. At the Worland, Wyoming Airport, the low of minus 4 on the morning of October 30th broke the all time October record of minus 3 that was set in 1991.

Extreme Cold/Wind Chill in YELLOWSTONE NATIONAL PARK, WYOMING
From 28-OCT-19 00:00:00 to 30-OCT-19 23:59:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Very cold temperatures occurred in Yellowstone Park. Some of the coldest temperatures included minus 25 at the Old Faithful Ranger Station and minus 24 at the northeast Entrance. These low temperatures occurred on the morning of October 30th.

Extreme Cold/Wind Chill in UPPER GREEN RIVER BASIN FOOTHILLS, WYOMING
From 28-OCT-19 00:00:00 to 30-OCT-19 23:59:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Very cold temperatures occurred in the Foothills of the Upper Green River Basin. On the morning of October 30th, the temperatures fell to 17 degrees below zero.

Extreme Cold/Wind Chill in UPPER GREEN RIVER BASIN, WYOMING
From 28-OCT-19 00:00:00 to 30-OCT-19 23:59:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Extremely cold temperatures occurred in the Upper Green River Basin. At the Big Piney, Wyoming Airport, the temperatures dropped to minus 26 degrees on the morning of October 30th. This shattered the old record of 3 degrees set in 2006. Many other locations had low temperatures between 10 and 20 below zero.

Extreme Cold/Wind Chill in ROCK SPRINGS & GREEN RIVER, WYOMING
From 28-OCT-19 00:00:00 to 30-OCT-19 23:59:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Extremely cold temperatures occurred around the region. Some of the lowest included minus 19 east of Little America and minus 13 in Green River, Wyoming.

Avalanche in EAST SWEETWATER COUNTY, WYOMING
From 28-OCT-19 00:00:00 to 30-OCT-19 23:59:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Extremely cold temperatures occurred in eastern Sweetwater County. At the Rock Springs, Wyoming Airport, the low temperatures of minus 9 on October 30th set the all time October record low. The old record was 3 degrees in 1991.

Cold/Wind Chill in JACKSON HOLE, WYOMING
From 28-OCT-19 00:00:00 to 30-OCT-19 23:59:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Low temperatures throughout the Jackson Valley ranged from around 0 to as low as minus 15 on the morning of October 30th.

Cold/Wind Chill in NORTH BIG HORN BASIN, WYOMING
From 28-OCT-19 00:00:00 to 31-OCT-19 23:59:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Record cold temperatures occurred at the Greybull airport three nights in a row. The coldest temperature occurred on October 30th with a temperature of three degrees occurring. This record low temperature broke set an all time low for the month, which was nine degrees set in 2006.

Extreme Cold/Wind Chill in GREEN MOUNTAINS & RATTLESNAKE RANGE, WYOMING
From 28-OCT-19 00:00:00 to 30-OCT-19 23:59:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Bitterly cold temperatures occurred in the Green Mountains. The coldest temperature recorded was 27 below zero at Jeffrey City, Wyoming.

Extreme Cold/Wind Chill in UPPER WIND RIVER BASIN, WYOMING
From 28-OCT-19 00:00:00 to 30-OCT-19 23:59:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Temperatures were very cold around the Upper Wind River Basin. Some of the notable temperatures on October 30th included minus 11 at Crowheart and minus 8 at the Dubois, Wyoming airport.

Extreme Cold/Wind Chill in WIND RIVER BASIN, WYOMING
From 28-OCT-19 00:00:00 to 30-OCT-19 23:59:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Record low temperatures occurred in the Wind River Basin. Temperatures around Riverton, Wyoming ranged from minus 5 to a low of minus 16 near Hudson, Wyoming. At the Riverton, Wyoming airport, the temperatures dropped to minus 9, setting an all time record low for the month of October. The old October record was 0 set in 2009.

Extreme Cold/Wind Chill in LANDER FOOTHILLS, WYOMING
From 28-OCT-19 00:00:00 to 30-OCT-19 23:59:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Extremely cold temperatures occurred around the Lander, Wyoming Foothills. At the Lander, Wyoming airport on October 30th, the temperature dropped to minus 10, which broke the all time record low of minus 3 that occurred back in 1971.

Extreme Cold/Wind Chill in SOUTHWEST BIG HORN BASIN, WYOMING
From 28-OCT-19 00:00:00 to 30-OCT-19 23:59:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Temperatures around Hot Springs county, Wyoming dropped as low as 10 below zero.