All-time weather records — Grinnell, IA

Record high
107.1°F
August 3, 1930
Record low
-35.0°F
February 3, 1996
Wettest day
80.06 in
June 15, 1925

Climate change signal in Grinnell

10.4%

of Grinnell's all-time daily heat records were set in the last decade (38 of 366 records since 2015).

4.1%

of all-time daily cold records were set in the last decade (15 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
4
4
1900s
15
24
1910s
72
20
1920s
51
18
1930s
30
7
1940s
7
2
1950s
35
26
1960s
20
34
1970s
8
78
1980s
31
58
1990s
17
44
2000s
23
21
2010s
27
22
2020s
26
8

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 1895, the latest in 2026. Period of observation: 1893-2026.

Records by month

Month Hottest day Coldest day Wettest day
January 64.0°F — Jan 9, 2003 -34.1°F — Jan 13, 1974 2.14 in — Jan 4, 1971
February 77.0°F — Feb 27, 2024 -35.0°F — Feb 3, 1996 2.50 in — Feb 25, 2007
March 90.0°F — Mar 22, 2026 -17.0°F — Mar 1, 1962 2.24 in — Mar 31, 1993
April 91.9°F — Apr 23, 1980 1.0°F — Apr 6, 1982 4.17 in — Apr 13, 1991
May 98.1°F — May 22, 1925 19.0°F — May 3, 2005 6.74 in — May 26, 2013
June 102.0°F — Jun 5, 1911 35.1°F — Jun 1, 1993 80.06 in — Jun 15, 1925
July 106.0°F — Jul 3, 1911 28.9°F — Jul 5, 1920 3.82 in — Jul 1, 2014
August 107.1°F — Aug 3, 1930 36.0°F — Aug 20, 1950 6.92 in — Aug 5, 1970
September 100.9°F — Sep 4, 1925 21.0°F — Sep 29, 1984 5.52 in — Sep 30, 1919
October 95.0°F — Oct 6, 1963 1.9°F — Oct 28, 1925 70.01 in — Oct 13, 1923
November 82.0°F — Nov 1, 1968 -15.0°F — Nov 30, 1976 3.35 in — Nov 18, 1958
December 69.1°F — Dec 5, 1998 -32.1°F — Dec 19, 1985 2.35 in — Dec 14, 2015

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