Waterloo, IA: records

4 October 2026: The hottest day on record in Waterloo, IA: 112°F on Tuesday 14 July 1936 and Monday 13 July 1936.

The record begins: 1895

All-time records

Hottest day: 112°F; 14 July 1936, 13 July 1936
Coldest night: -34°F; 16 January 2009, 1 March 1962
Wettest day: 6.00 in; 8 September 1941
Warmest night: 80°F; 16 August 1988, 31 July 1917
Coldest day: -16°F; 2 February 1996

Daily records by decade

New daily records set in Waterloo, IA by decade since the 1920s: the most record highs, 143, came in the 1930s; the most record lows, 77, in the 1920s.

Record highs
Record lows

Every decade as a table

Decade	Record highs	Record lows	Years in the record
1890s	0	0	5
1900s	0	0	10
1910s	0	0	10
1920s	62	77	10
1930s	143	69	10
1940s	41	48	10
1950s	17	49	10
1960s	27	54	10
1970s	21	58	10
1980s	42	38	10
1990s	30	19	10
2000s	32	22	10
2010s	26	17	10
2020s	37	5	7

Records by month

Month	Highest	Lowest	Wettest day
January	65°F 26 January 2002	-34°F 16 January 2009	2.04 in 29 January 1909
February	78°F 26 February 2024	-31°F 3 February 1996, 2 February 1996	1.80 in 28 February 1948
March	87°F 21 March 2026, 29 March 1986	-34°F 1 March 1962	1.95 in 30 March 1998
April	100°F 22 April 1980	-4°F 6 April 1982	3.05 in 25 April 2008
May	108°F 31 May 1934	22°F 3 May 2005, 4 May 1907	3.41 in 29 May 1980
June	107°F 28 June 1934, 27 June 1934	33°F 1 June 1897	4.35 in 15 June 1980
July	112°F 14 July 1936, 13 July 1936	42°F 7 July 1984	5.49 in 2 July 1999
August	110°F 18 August 1936	33°F 20 August 1950	4.92 in 20 August 1966
September	102°F 7 September 1939, 6 September 1922	19°F 30 September 1899	6.00 in 8 September 1941
October	95°F 3 October 1997, 6 October 1963, 12 October 1930	0°F 30 October 1925	2.94 in 22 October 2020
November	83°F 1 November 1933	-17°F 26 November 1977	2.55 in 5 November 1938
December	74°F 15 December 2021	-29°F 25 December 2000, 10 December 1919	3.32 in 13 December 2015

Streaks, months and years

Longest heat streak	21 days	28 June to 18 July 1921	A high of 90°F or above
Longest cold streak	52 days	30 December 1978 to 19 February 1979	A high of 32°F or below
Wettest month	13.35 in	September 2018
Driest month	a trace	November 1954
Wettest year	54.15 in	2018
Driest year	17.35 in	1910

Every record in words

The coldest night on record in Waterloo, IA: a low of -34°F on Friday 16 January 2009 and Thursday 1 March 1962.
The wettest day on record in Waterloo, IA: 6.00 in on Monday 8 September 1941.
The warmest night on record in Waterloo, IA: a low of 80°F on Tuesday 16 August 1988 and Tuesday 31 July 1917.
The coldest day on record in Waterloo, IA: a high of -16°F on Friday 2 February 1996.
The longest run of days with a high of 90°F or above in Waterloo, IA: 21 days, from Tuesday 28 June to Monday 18 July 1921.
The longest run of days with a high of 32°F or below in Waterloo, IA: 52 days, from Saturday 30 December 1978 to Monday 19 February 1979.
The wettest month on record in Waterloo, IA: September 2018, with 13.35 in of precipitation.
The driest month on record in Waterloo, IA: November 1954, with a trace of precipitation.
The wettest year on record in Waterloo, IA: 2018, with 54.15 in of precipitation.
The driest year on record in Waterloo, IA: 1910, with 17.35 in of precipitation.

Waterloo, IA the day's answers