Earliest and Latest Days of 100° F in Casper

This is a list of the earliest and latest days in the year with a high temperature of at least 100 °F in Casper, Wyoming history. It is based on NOAA data from the years 1900–2024.

Also see:

Earliest 100 degree day in Casper?

The earliest in the year that Casper, Wyoming had a high temperature of at least 100 °F is June 15 which happened in 2021.

Latest 100 degree day in Casper?

The latest in the year that Casper, Wyoming had a high temperature of at least 100 °F is September 24 which happened in 1911.

Earliest Days ≥ 100 °F

Date	Year	Temperature
June 15	2021	101 °F
June 20	1912	100 °F
June 21	2016	100 °F
June 23	1990	100 °F
June 23	1988	100 °F
June 23	1954	101 °F
June 24	2012	100 °F
June 24	2007	100 °F
June 24	1988	102 °F
June 25	2012	100 °F
June 26	1994	100 °F
June 27	1990	101 °F
June 27	1970	101 °F
June 30	2002	100 °F
June 30	1990	102 °F
June 30	1912	100 °F
July 1	2012	100 °F
July 1	1912	100 °F
July 2	1990	101 °F
July 2	1912	101 °F

Latest Days ≥ 100 °F

Date	Year	Temperature
September 24	1911	100 °F
September 21	1911	100 °F
September 20	1911	100 °F
September 19	1911	103 °F
September 18	1911	101 °F
September 15	1911	101 °F
September 14	1911	102 °F
September 11	1911	100 °F
September 7	1911	100 °F
September 5	1911	101 °F
September 4	2022	100 °F
September 4	1911	100 °F
September 3	1911	100 °F
September 2	1911	100 °F
September 1	1911	100 °F
August 28	1912	107 °F
August 27	1912	104 °F
August 26	1912	109 °F
August 25	1912	108 °F
August 24	1912	104 °F