Chicago, IL

Illinois · Records since 1872–2026

🌤️ 76°F Feels like 82°
Currently in Chicago
As of 5:45 PM CDT

Records for July 27

🔥 Record High

100°F

July 27, 1955

+16° from 84° normal

❄ Record Low

52°F

July 27, 1985

-15° from 67° normal
🌞 Normal high: 84°F 🌑 Normal low: 67°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 — July 27

# Temp Date
🏆 100°F July 27, 1955
2 100°F July 27, 1916
3 96°F July 27, 1941
4 96°F July 27, 1930
5 96°F July 27, 1919
6 95°F July 27, 1952
7 95°F July 27, 1901
8 94°F July 27, 1913
9 94°F July 27, 1887
10 93°F July 27, 1989

Top 5 Record Lows — July 27

# Temp Date
🥶 52°F July 27, 1985
2 54°F July 27, 1971
3 55°F July 27, 2013
4 55°F July 27, 1991
5 55°F July 27, 1984
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.
1
day
Hot Streak
1 consecutive day at or above 91°F · since July 26
2 more days to heat wave status

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
14
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

107 of 207 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

29
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

24.15"
2026 YTD
Normal: 21.81"
+2.34"
3.56"
July so far
July normal: 3.71"
-0.15"
8.56"
Summer so far
Summer normal: 12.06"
-3.50"
7
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")