Casper, WY Climate

Summary Graph

The summary climate graph for Casper, WY shows a selection of temperature, rainfall and snow minimum, mean and maximum measures over the course of a year. Click on each of the measures in the key to toggle them on and off.

Graph of average and extreme temperature ranges by day for Casper, WY.


The warmest month in Natrona Co International, Casper, Wyoming is July with an average high temperature of 89.3°F. The hottest day on record was July 12 1954 when the temperature hit 104.4°F. During January the overnight temperature drops to an average of 14.4°F with the lowest temperature of -41.1°F being recorded on December 22 1990.

Warmest Days

Warmest Months

Coldest Days

Coldest Months

The warmest days on record are:

12 Jul 1954104.4°F
30 Jul 2006104°F
19 Jul 1998102.9°F
25 Jun 1988102°F
9 Jul 1989102°F

The warmest months on average were:

July 200695°F
July 201294.7°F
July 200294.3°F
July 200094.1°F
July 200393.9°F

The coldest days on record are:

22 Dec 1990-41.1°F
24 Dec 1983-38.9°F
31 Dec 1978-34.1°F
29 Jan 1980-32.1°F
18 Feb 2006-32.1°F

The coldest months on average were:

January 1979-0.8°F
December 1983-0.8°F
January 19632.6°F
February 19893.5°F
December 19904.2°F


The wettest month in Casper, WY is May with an average of 1.9 inches of rain falling on 12 to 13 days. The driest month in Casper, WY is January with an average of 0.5 inches of rain falling on 0 to 1 days.

Wettest Days

The wettest days on record are:

6 May 20072.2 inches
22 May 19522.1 inches
16 May 19912.1 inches
18 May 19781.8 inches
6 May 19931.7 inches

Wettest Months

The wettest months on record are:

July 200611.9 inches
May 19956 inches
May 19785.6 inches
June 20034.9 inches
May 20084.8 inches

Driest Months

The driest months on record are:

February 19400 inches
March 19400 inches
April 19400 inches
May 19400 inches
June 19400 inches