Chicago Threshold Days: Hot, Cold and Wet Days per Year

18 fixed thresholds counted per year for Chicago: days at or above 30 C and 100 F, frost, tropical nights and heavy rain, with rankings and streaks.

Key Facts for Chicago Thresholds

Chicago: days with a maximum temperature at or above 30 C (86 F) in 68 years, most in 2012 with 67.
Chicago: days with a maximum temperature at or above 90 F (32.2 C) in 68 years, most in 1988 with 47.
Chicago: days with a maximum temperature at or below Ice days (max at or below 0 C) (32 F) in 68 years, most in 1978 with 74.
Chicago: nights with a minimum temperature at or below Frost days (min at or below 0 C) (32 F) in 68 years, most in 1964 with 150.
18 fixed thresholds have at least one qualifying day at Chicago.

Days at or above 30 C (86 F)

68 years with a qualifying day

Days per year in Chicago with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 67 in 2012.

Days at or above 30 C (86 F) per year in Chicago
Year	Days	Decade average
1959	58	58
1960	32	31.5
1961	30	31.5
1962	36	31.5
1963	37	31.5
1964	40	31.5
1965	19	31.5
1966	44	31.5
1967	15	31.5
1968	36	31.5
1969	26	31.5
1970	40	37
1971	53	37
1972	33	37
1973	32	37
1974	20	37
1975	38	37
1976	35	37
1977	48	37
1978	33	37
1979	38	37
1980	43	40.6
1981	26	40.6
1982	28	40.6
1983	59	40.6
1984	38	40.6
1985	30	40.6
1986	34	40.6
1987	58	40.6
1988	63	40.6
1989	27	40.6
1990	29	37.5
1991	60	37.5
1992	15	37.5
1993	29	37.5
1994	41	37.5
1995	58	37.5
1996	23	37.5
1997	30	37.5
1998	45	37.5
1999	45	37.5
2000	24	34
2001	42	34
2002	48	34
2003	26	34
2004	14	34
2005	61	34
2006	35	34
2007	49	34
2008	26	34
2009	15	34
2010	50	42.6
2011	49	42.6
2012	67	42.6
2013	36	42.6
2014	27	42.6
2015	23	42.6
2016	45	42.6
2017	41	42.6
2018	56	42.6
2019	32	42.6
2020	64	48.7
2021	56	48.7
2022	44	48.7
2023	48	48.7
2024	48	48.7
2025	48	48.7
2026	33	48.7

For each year, a bar from the first to the last day in Chicago meeting 30 C (86 F).

First to last qualifying date each year in Chicago
Year	First date	Last date
1959	1959-05-02	1959-09-22
1960	1960-04-23	1960-09-08
1961	1961-05-13	1961-09-11
1962	1962-05-14	1962-10-15
1963	1963-05-08	1963-10-06
1964	1964-05-18	1964-09-10
1965	1965-05-01	1965-09-19
1966	1966-06-04	1966-09-13
1967	1967-05-26	1967-10-04
1968	1968-06-05	1968-09-03
1969	1969-05-27	1969-08-31
1970	1970-04-29	1970-09-21
1971	1971-05-17	1971-10-02
1972	1972-05-20	1972-08-31
1973	1973-06-08	1973-09-03
1974	1974-06-20	1974-09-19
1975	1975-05-18	1975-10-13
1976	1976-06-07	1976-09-08
1977	1977-04-17	1977-09-04
1978	1978-05-26	1978-09-20
1979	1979-05-08	1979-09-12
1980	1980-04-22	1980-09-20
1981	1981-03-31	1981-09-10
1982	1982-05-05	1982-10-06
1983	1983-06-11	1983-10-02
1984	1984-05-18	1984-09-19
1985	1985-04-19	1985-09-19
1986	1986-03-29	1986-09-27
1987	1987-04-20	1987-09-27
1988	1988-05-28	1988-09-18
1989	1989-05-24	1989-09-08
1990	1990-04-24	1990-09-10
1991	1991-05-13	1991-09-15
1992	1992-05-01	1992-08-25
1993	1993-05-09	1993-08-30
1994	1994-04-26	1994-09-16
1995	1995-06-06	1995-09-05
1996	1996-05-17	1996-09-05
1997	1997-06-20	1997-10-08
1998	1998-05-15	1998-09-27
1999	1999-05-28	1999-09-26
2000	2000-05-06	2000-09-19
2001	2001-05-03	2001-09-07
2002	2002-04-15	2002-09-10
2003	2003-04-15	2003-09-07
2004	2004-04-18	2004-09-15
2005	2005-06-04	2005-10-04
2006	2006-05-27	2006-08-23
2007	2007-05-14	2007-10-08
2008	2008-06-02	2008-09-02
2009	2009-06-19	2009-08-16
2010	2010-05-23	2010-10-09
2011	2011-05-10	2011-09-12
2012	2012-03-21	2012-09-12
2013	2013-05-14	2013-09-11
2014	2014-05-08	2014-09-05
2015	2015-06-10	2015-09-07
2016	2016-05-24	2016-09-19
2017	2017-05-16	2017-09-26
2018	2018-05-01	2018-10-03
2019	2019-06-26	2019-10-01
2020	2020-05-24	2020-09-03
2021	2021-04-27	2021-09-27
2022	2022-05-10	2022-09-20
2023	2023-05-07	2023-10-03
2024	2024-05-20	2024-09-21
2025	2025-05-15	2025-10-04
2026	2026-05-17	2026-09-12

Every Fixed Threshold

Fixed thresholds in Chicago
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days	Page
30 C (86 F): Days	68	67	2012	33	Full page
35 C (95 F): Days	49	22	1988	6	Full page
40 C (104 F): Days	2	1	1988	1	Too few years
90 F (32.2 C): Days	68	47	1988	16	Full page
100 F (37.8 C): Days	10	7	1988	1	Full page
Ice days (max at or below 0 C) (32 F): Ice days (max	68	74	1978	32	Full page
Frost days (min at or below 0 C) (32 F): Frost days (min	68	150	1964	71	Full page
-10 C (14 F): Days with min	68	64	1963	19	Full page
-20 C (-4 F): Days with min	58	36	1963	2	Full page
-30 C (-22 F): Days with min	5	3	1982	1	Full page
Tropical nights (min at or above 20 C) (68 F): Tropical nights (min	68	56	2020	42	Full page
25 C (77 F): Days with min	34	9	2012	5	Full page
Days with 10 mm or more rain (0.39 in): Days with 10 mm or more rain	68	41	2019	28	Full page
Days with 25 mm or more rain (0.98 in): Days with 25 mm or more rain	68	18	1983	12	Full page
Days with 50 mm or more rain (1.97 in): Days with 50 mm or more rain	51	5	2002	1	Full page
Days with 100 mm or more rain (3.94 in): Days with 100 mm or more rain	9	1	1969	1	Full page
Days with 10 cm or more snowfall (3.9 in): Days with 10 cm or more snowfall	55	6	1965	1	Full page
Days with 25 cm or more snowfall (9.8 in): Days with 25 cm or more snowfall	10	1	1967	1	Full page

A full page with streaks and every date exists for thresholds with at least 5 qualifying years. Years with under 90 percent of days observed are left out of the most days column.

Download the Data

Data for Chicago threshold days by year: CSV or JSON. Field meanings are on the data page.

Source: NOAA National Centers for Environmental Information, Global Historical Climatology Network Daily (GHCN-Daily). Records are computed by World Extreme Weather Monitor and are not official NOAA products. (US Government open data (NOAA NCEI)) Data as of 2026-10-12 (12 October 2026). Threshold counts are computed by this site from the threaded city record.

Data as of 2026-10-12. Last revised 12 October 2026 (2026-10-12).

Chicago Threshold Days: Hot, Cold and Wet Days per Year

Key Facts for Chicago Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

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