All-time weather records — Norwalk, IA

Record high
108.0°F
August 16, 1983
Record low
-26.0°F
February 3, 1996
Wettest day
6.18 in
August 27, 1975

Climate change signal in Norwalk

17.2%

of Norwalk's all-time daily heat records were set in the last decade (63 of 366 records since 2015).

4.9%

of all-time daily cold records were set in the last decade (18 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 #
1940s
22
33
1950s
49
65
1960s
40
74
1970s
37
56
1980s
57
58
1990s
27
38
2000s
36
15
2010s
64
14
2020s
34
13

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 1946, the latest in 2026. Period of observation: 1945-2026.

Records by month

Month Hottest day Coldest day Wettest day
January 66.9°F — Jan 8, 2003 -24.0°F — Jan 21, 1970 2.13 in — Jan 12, 1960
February 78.1°F — Feb 26, 2024 -26.0°F — Feb 3, 1996 1.76 in — Feb 27, 1948
March 91.0°F — Mar 21, 2026 -22.0°F — Mar 1, 1962 2.11 in — Mar 7, 1990
April 93.0°F — Apr 22, 1980 9.0°F — Apr 3, 1975 3.80 in — Apr 28, 1974
May 99.0°F — May 27, 2018 28.0°F — May 6, 1947 3.84 in — May 19, 2025
June 102.9°F — Jun 21, 1988 41.0°F — Jun 3, 1998 4.53 in — Jun 9, 2011
July 106.0°F — Jul 25, 2012 46.9°F — Jul 30, 1971 3.55 in — Jul 31, 2024
August 108.0°F — Aug 16, 1983 39.9°F — Aug 20, 1950 6.18 in — Aug 27, 1975
September 100.9°F — Sep 9, 2013 28.0°F — Sep 29, 1984 4.42 in — Sep 12, 1961
October 95.0°F — Oct 5, 1963 14.0°F — Oct 19, 1972 3.59 in — Oct 1, 2019
November 81.0°F — Nov 13, 1999 -4.0°F — Nov 8, 1991 3.18 in — Nov 3, 2003
December 73.9°F — Dec 15, 2021 -22.0°F — Dec 23, 1989 1.79 in — Dec 13, 2015

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