Earliest and Latest Days of 100° F in St. Louis

This is a list of the earliest and latest days in the year with a high temperature of at least 100 °F in St. Louis, Missouri history. It is based on NOAA data from the years 1893–2024.

Also see:

Earliest 100 degree day in St. Louis?

The earliest in the year that St. Louis, Missouri had a high temperature of at least 100 °F is June 1 which happened in 1934.

Latest 100 degree day in St. Louis?

The latest in the year that St. Louis, Missouri had a high temperature of at least 100 °F is September 29 which happened in 1953.

Earliest Days ≥ 100 °F

Date	Year	Temperature
June 1	1934	100 °F
June 10	1953	100 °F
June 13	2022	100 °F
June 15	1952	101 °F
June 16	1952	100 °F
June 16	1918	100 °F
June 18	2021	101 °F
June 18	1953	100 °F
June 19	1953	102 °F
June 19	1936	104 °F
June 20	1953	103 °F
June 22	1988	101 °F
June 22	1930	101 °F
June 23	1934	100 °F
June 23	1930	100 °F
June 23	1901	100 °F
June 24	1988	102 °F
June 25	1988	101 °F
June 25	1954	102 °F
June 25	1952	101 °F
June 25	1931	100 °F

Latest Days ≥ 100 °F

Date	Year	Temperature
September 29	1953	102 °F
September 15	1939	101 °F
September 14	1971	100 °F
September 14	1939	101 °F
September 13	1939	100 °F
September 9	1925	101 °F
September 8	1947	101 °F
September 8	1939	100 °F
September 7	1939	101 °F
September 7	1899	100 °F
September 6	1990	101 °F
September 6	1954	101 °F
September 6	1925	102 °F
September 6	1899	102 °F
September 5	1990	101 °F
September 5	1954	103 °F
September 5	1925	103 °F
September 5	1899	102 °F
September 4	1954	104 °F
September 4	1925	102 °F
September 4	1899	100 °F