All-time weather records — Decorah, IA

Record high
111.0°F
July 14, 1936
Record low
-43.1°F
January 30, 1951
Wettest day
8.64 in
August 18, 2025

Climate change signal in Decorah

17.8%

of Decorah's all-time daily heat records were set in the last decade (65 of 366 records since 2015).

2.5%

of all-time daily cold records were set in the last decade (9 of 366 records since 2015).

If records were spread evenly across the station's history, you'd expect roughly 5% per decade. Decade-by-decade, here's where each record-breaking day was set:

Decade Heat records set # Cold records set #
1890s
19
41
1900s
16
21
1910s
36
43
1920s
13
67
1930s
76
36
1940s
11
9
1950s
17
41
1960s
14
30
1970s
2
21
1980s
21
12
1990s
26
22
2000s
31
12
2010s
32
9
2020s
52
2

Records are the all-time daily extremes that are still standing — each daily record can only be held by one year. The station's earliest hot record was set in 1893, the latest in 2026. Period of observation: 1893-2026.

Records by month

Month Hottest day Coldest day Wettest day
January 62.1°F — Jan 30, 2025 -43.1°F — Jan 30, 1951 1.25 in — Jan 25, 1967
February 73.9°F — Feb 26, 2024 -41.1°F — Feb 3, 1996 1.94 in — Feb 22, 1922
March 84.9°F — Mar 28, 2025 -33.0°F — Mar 1, 1962 2.30 in — Mar 14, 1913
April 93.0°F — Apr 22, 1980 5.0°F — Apr 6, 1982 3.74 in — Apr 23, 1968
May 102.0°F — May 31, 1934 19.9°F — May 3, 1908 3.75 in — May 4, 2018
June 105.1°F — Jun 27, 1934 28.9°F — Jun 1, 1897 6.60 in — Jun 8, 2008
July 111.0°F — Jul 14, 1936 37.9°F — Jul 14, 1926 6.08 in — Jul 29, 1970
August 105.1°F — Aug 23, 2023 32.0°F — Aug 30, 1915 8.64 in — Aug 18, 2025
September 100.0°F — Sep 1, 1913 18.0°F — Sep 26, 1926 4.79 in — Sep 21, 1986
October 93.9°F — Oct 6, 1963 -7.1°F — Oct 30, 1925 3.08 in — Oct 10, 1904
November 79.0°F — Nov 1, 1933 -16.1°F — Nov 26, 1977 2.62 in — Nov 10, 1975
December 69.1°F — Dec 15, 2021 -36.0°F — Dec 27, 1950 1.52 in — Dec 14, 2015

Click a month to see every daily record for that month in Decorah.