Chicago, IL

Illinois · Records since 1872–2026

☁️ 72°F Feels like 79°
Currently in Chicago
As of 3:30 AM CDT

Records for August 11

🔥 Record High

98°F

August 11, 1941

+15° from 83° normal

❄ Record Low

47°F

August 11, 1982

-19° from 66° normal
🌞 Normal high: 83°F 🌑 Normal low: 66°F 1991–2020 normals

All-Time Records — Chicago

🔥
105°F
Hottest Day Ever
Jul 24, 1934
-27°F
Coldest Day Ever
Jan 20, 1985
🌧
6.86"
Wettest Day Ever
Jul 23, 2011
18.6"
Most Snow in One Day
Jan 2, 1999

Top 10 Record Highs — August 11

# Temp Date
🏆 98°F August 11, 1941
2 98°F August 11, 1874
3 96°F August 11, 1944
4 95°F August 11, 1947
5 94°F August 11, 1975
6 94°F August 11, 1943
7 93°F August 11, 2002
8 93°F August 11, 1995
9 92°F August 11, 2016
10 92°F August 11, 1988

Top 5 Record Lows — August 11

# Temp Date
🥶 47°F August 11, 1982
2 51°F August 11, 1965
3 53°F August 11, 2004
4 54°F August 11, 1991
5 54°F August 11, 1986
About this data — Records are sourced from the NOAA Threadex dataset via RCC ACIS, a quality-controlled record for long-term climate stations. Threadex adjusts for station relocations and observation-time changes, making records comparable across all years since 1872–2026. Climate normals represent the 1991–2020 average.

Heat Wave Summary — Chicago

threshold: 91°F (90th percentile of historical Jun–Aug highs)
3.9
Avg heat wave length
days (historical)
96°
Avg peak temp
during heat waves
19
Dangerous nights 2026
Overnights ≥ 70°F
2
Heat waves 2026
so far

2026 Daily High Temperature vs Normal

Year to date
Above normal Below normal

114 of 222 days with data were above the 1991–2020 normal high for their date.


Days ≥ 90°F Per Year

1872–2026
12
2026 so far
16
Avg/year 1970–2025
21
Avg/year (last 10 complete)
47
Most in a year (1988)

Average Daily High by Decade

Full year · complete decades only


Longest Heat Waves — Chicago

# Dates Days Peak Avg High Avg Overnight Low
🏆 Aug 25, 1953 – Sep 3, 1953 10 101°F (Sep 1) 98°F 71°F
2 Jul 26, 1955 – Aug 4, 1955 10 100°F (Jul 27) 96°F 76°F
3 Aug 19, 1959 – Aug 28, 1959 10 96°F (Aug 21) 94°F 74°F
4 Jul 27, 1988 – Aug 4, 1988 9 100°F (Aug 1) 97°F 72°F
5 Jul 17, 1987 – Jul 25, 1987 9 96°F (Jul 20) 93°F 71°F
6 Jun 30, 2012 – Jul 7, 2012 8 103°F (Jul 5) 98°F 75°F
7 Aug 17, 1947 – Aug 24, 1947 8 100°F (Aug 24) 97°F 74°F
8 Aug 22, 1948 – Aug 29, 1948 8 98°F (Aug 24) 95°F 72°F
9 May 16, 1977 – May 23, 1977 8 95°F (May 20) 92°F 70°F
10 Aug 4, 1900 – Aug 11, 1900 8 94°F (Aug 4) 93°F 75°F

Heat Waves Per Year


Warm Summer Nights (Jun–Aug)

Nights where the overnight low exceeded the 1991–2020 normal low

37
2026 so far
above-normal nights
35.8
Avg / summer
1970–2020
72
Most in a summer
1921

Above-Normal Summer Nights Per Year

Average June–August Low by Decade

Overnight lows · complete decades only

Precipitation

Actual vs. 1991–2020 full-month and full-season normals

29.18"
2026 YTD
Normal: 23.84"
+5.34"
3.23"
August so far
August normal: 4.25"
-1.02"
13.59"
Summer so far
Summer normal: 12.06"
+1.53"
10
2026 heavy rain days
Days with ≥ 1.0"

Monthly Precipitation — Last 24 Months

Blue = actual · dashed line = monthly normal

Annual Precipitation Per Year (1970–2026)

Blue = above average · tan = below average · gold = 2026 (partial)

Heavy Rain Days Per Year (≥ 1.0")

Compare year-to-year changes in days with heavy rainfall (≥ 1.0")

Month in Review — July 2026

76.8°F

Average temperature · July 2026

28th-warmest month on record

22nd-warmest July of 155 on record

+2.2° vs. 74.6° average (1991–2020)
81.3°F
Warmest month ever
July 1955
81.3°F
Warmest July ever
1955
9
Days ≥ 90°F
in July
96°F
Hottest of 2026
Jul 14

Longest 90°F Streak in July

6 consecutive days with highs of at least 90°F (Jul 13–18, 2026, peaking at 96°F)

The longest July streak since 2012 (14 years). The July record is 10 days, set in 1987.


Average July Temperature by Year

1872–2026 · 2026 highlighted


Warmest Julys on Record

# Year Avg Temp
1 1955 81.3°F
2 1921 81.2°F
3 2012 81.0°F
4 2020 79.2°F
5 2011 79.1°F
6 1916 78.5°F
7 1977 78.5°F
8 1999 78.3°F
9 1966 78.3°F
10 1949 77.9°F

Warmest Months on Record (Any Month)

# Month Avg Temp
1 July 1955 81.3°F
2 July 1921 81.2°F
3 July 2012 81.0°F
4 August 1947 80.2°F
5 July 2020 79.2°F
6 July 2011 79.1°F
7 August 1995 79.0°F
8 August 1955 78.7°F
9 August 1959 78.7°F
10 July 1916 78.5°F

Nearby Stations — July 2026

How the same month ranked at the closest reporting stations

Station Avg Temp July Rank
Chicago, IL 76.8°F 22nd of 155
South Bend, IN 74.8°F 32nd of 131
Rockford, IL 74.9°F 46th of 128
Milwaukee, WI 75.0°F 15th of 156
Holland, MI 73.4°F 25th of 118
About this data. Monthly averages are the mean of daily average temperatures, computed from NOAA Threadex records via RCC ACIS. Months missing more than three days of observations are excluded from the rankings, so the in-progress month never appears. Rankings cover 1849 complete months on record.