| Climate data for Chicago (Midway International Airport), 1991–2020 normals,[a] extremes 1928–present | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
| Record high °F (°C) | 67 (19) |
75 (24) |
86 (30) |
92 (33) |
102 (39) |
107 (42) |
109 (43) |
104 (40) |
102 (39) |
94 (34) |
81 (27) |
72 (22) |
109 (43) |
| Mean maximum °F (°C) | 53.4 (11.9) |
57.9 (14.4) |
72.0 (22.2) |
81.5 (27.5) |
89.2 (31.8) |
93.9 (34.4) |
96.0 (35.6) |
94.2 (34.6) |
90.8 (32.7) |
82.8 (28.2) |
68.0 (20.0) |
57.5 (14.2) |
97.1 (36.2) |
| Mean daily maximum °F (°C) | 32.8 (0.4) |
36.8 (2.7) |
47.9 (8.8) |
60.0 (15.6) |
71.5 (21.9) |
81.2 (27.3) |
85.2 (29.6) |
83.1 (28.4) |
76.5 (24.7) |
63.7 (17.6) |
49.6 (9.8) |
37.7 (3.2) |
60.5 (15.8) |
| Daily mean °F (°C) | 26.2 (−3.2) |
29.9 (−1.2) |
39.9 (4.4) |
50.9 (10.5) |
61.9 (16.6) |
71.9 (22.2) |
76.7 (24.8) |
75.0 (23.9) |
67.8 (19.9) |
55.3 (12.9) |
42.4 (5.8) |
31.5 (−0.3) |
52.4 (11.3) |
| Mean daily minimum °F (°C) | 19.5 (−6.9) |
22.9 (−5.1) |
32.0 (0.0) |
41.7 (5.4) |
52.4 (11.3) |
62.7 (17.1) |
68.1 (20.1) |
66.9 (19.4) |
59.2 (15.1) |
46.8 (8.2) |
35.2 (1.8) |
25.3 (−3.7) |
44.4 (6.9) |
| Mean minimum °F (°C) | −3 (−19) |
3.4 (−15.9) |
14.1 (−9.9) |
28.2 (−2.1) |
39.1 (3.9) |
49.3 (9.6) |
58.6 (14.8) |
57.6 (14.2) |
45.0 (7.2) |
31.8 (−0.1) |
19.7 (−6.8) |
5.3 (−14.8) |
−6.5 (−21.4) |
| Record low °F (°C) | −25 (−32) |
−20 (−29) |
−7 (−22) |
10 (−12) |
28 (−2) |
35 (2) |
46 (8) |
43 (6) |
29 (−2) |
20 (−7) |
−3 (−19) |
−20 (−29) |
−25 (−32) |
| Average precipitation inches (mm) | 2.30 (58) |
2.12 (54) |
2.66 (68) |
4.15 (105) |
4.75 (121) |
4.53 (115) |
4.02 (102) |
4.10 (104) |
3.33 (85) |
3.86 (98) |
2.73 (69) |
2.33 (59) |
40.88 (1,038) |
| Average snowfall inches (cm) | 12.5 (32) |
10.1 (26) |
5.7 (14) |
1.0 (2.5) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.1 (0.25) |
1.5 (3.8) |
7.9 (20) |
38.8 (99) |
| Average precipitation days (≥ 0.01 in) | 11.5 | 9.4 | 11.1 | 12.0 | 12.4 | 11.1 | 10.0 | 9.3 | 8.4 | 10.8 | 10.2 | 10.8 | 127.0 |
| Average snowy days (≥ 0.1 in) | 8.9 | 6.4 | 3.9 | 0.9 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.2 | 1.6 | 6.3 | 28.2 |
| Average ultraviolet index | 1 | 2 | 4 | 6 | 7 | 9 | 9 | 8 | 6 | 4 | 2 | 1 | 5 |
| Source 1: NOAA[1][2][3], WRCC[4] | |||||||||||||
| Source 2: Weather Atlas (UV)[5] | |||||||||||||
| Climate data for Chicago (O'Hare Int'l Airport), 1991–2020 normals,[a] extremes 1871–present[b] | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
| Record high °F (°C) | 67 (19) |
75 (24) |
88 (31) |
91 (33) |
98 (37) |
104 (40) |
105 (41) |
102 (39) |
101 (38) |
94 (34) |
81 (27) |
71 (22) |
105 (41) |
| Mean maximum °F (°C) | 52.3 (11.3) |
56.8 (13.8) |
71.0 (21.7) |
80.9 (27.2) |
88.0 (31.1) |
93.1 (33.9) |
94.9 (34.9) |
93.2 (34.0) |
89.7 (32.1) |
81.7 (27.6) |
67.0 (19.4) |
56.4 (13.6) |
96.0 (35.6) |
| Mean daily maximum °F (°C) | 31.6 (−0.2) |
35.7 (2.1) |
47.0 (8.3) |
59.0 (15.0) |
70.5 (21.4) |
80.4 (26.9) |
84.5 (29.2) |
82.5 (28.1) |
75.5 (24.2) |
62.7 (17.1) |
48.4 (9.1) |
36.6 (2.6) |
59.5 (15.3) |
| Daily mean °F (°C) | 25.2 (−3.8) |
28.8 (−1.8) |
39.0 (3.9) |
49.7 (9.8) |
60.6 (15.9) |
70.6 (21.4) |
75.4 (24.1) |
73.8 (23.2) |
66.3 (19.1) |
54.0 (12.2) |
41.3 (5.2) |
30.5 (−0.8) |
51.3 (10.7) |
| Mean daily minimum °F (°C) | 18.8 (−7.3) |
21.8 (−5.7) |
31.0 (−0.6) |
40.3 (4.6) |
50.6 (10.3) |
60.8 (16.0) |
66.4 (19.1) |
65.1 (18.4) |
57.1 (13.9) |
45.4 (7.4) |
34.1 (1.2) |
24.4 (−4.2) |
43.0 (6.1) |
| Mean minimum °F (°C) | −4.5 (−20.3) |
0.5 (−17.5) |
11.8 (−11.2) |
25.6 (−3.6) |
36.7 (2.6) |
46.0 (7.8) |
54.5 (12.5) |
54.3 (12.4) |
41.8 (5.4) |
29.7 (−1.3) |
17.3 (−8.2) |
3.2 (−16.0) |
−8.5 (−22.5) |
| Record low °F (°C) | −27 (−33) |
−21 (−29) |
−12 (−24) |
7 (−14) |
27 (−3) |
35 (2) |
45 (7) |
42 (6) |
29 (−2) |
14 (−10) |
−2 (−19) |
−25 (−32) |
−27 (−33) |
| Average precipitation inches (mm) | 1.99 (51) |
1.97 (50) |
2.45 (62) |
3.75 (95) |
4.49 (114) |
4.10 (104) |
3.71 (94) |
4.25 (108) |
3.19 (81) |
3.43 (87) |
2.42 (61) |
2.11 (54) |
37.86 (962) |
| Average snowfall inches (cm) | 11.3 (29) |
10.7 (27) |
5.5 (14) |
1.3 (3.3) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.2 (0.51) |
1.8 (4.6) |
7.6 (19) |
38.4 (98) |
| Average extreme snow depth inches (cm) | 6.3 (16) |
6.3 (16) |
4.0 (10) |
0.6 (1.5) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
1.5 (3.8) |
3.9 (9.9) |
9.8 (25) |
| Average precipitation days (≥ 0.01 in) | 11.0 | 9.4 | 10.8 | 12.3 | 12.5 | 11.1 | 9.7 | 9.4 | 8.5 | 10.5 | 10.0 | 10.6 | 125.8 |
| Average snowy days (≥ 0.1 in) | 8.5 | 6.4 | 4.0 | 1.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.2 | 1.6 | 6.1 | 27.8 |
| Average relative humidity (%) | 72.2 | 71.6 | 69.7 | 64.9 | 64.1 | 65.6 | 68.5 | 70.7 | 71.1 | 68.6 | 72.5 | 75.5 | 69.6 |
| Average dew point °F (°C) | 13.6 (−10.2) |
17.6 (−8.0) |
27.1 (−2.7) |
35.8 (2.1) |
45.7 (7.6) |
55.8 (13.2) |
61.7 (16.5) |
61.0 (16.1) |
53.8 (12.1) |
41.7 (5.4) |
31.6 (−0.2) |
20.1 (−6.6) |
38.8 (3.8) |
| Mean monthly sunshine hours | 135.8 | 136.2 | 187.0 | 215.3 | 281.9 | 311.4 | 318.4 | 283.0 | 226.6 | 193.2 | 113.3 | 106.3 | 2,508.4 |
| Percent possible sunshine | 46 | 46 | 51 | 54 | 62 | 68 | 69 | 66 | 60 | 56 | 38 | 37 | 56 |
| Source: NOAA (relative humidity, dew point and sun 1961–1990)[2][8][9] | |||||||||||||
Notes
- ^ a b Mean monthly maxima and minima (i.e. the expected highest and lowest temperature readings at any point during the year or given month) calculated based on data at said location from 1991 to 2020.
- ^ Official records for Chicago were kept at various locations in downtown from January 1871 to December 31, 1925, University of Chicago from January 1, 1926 to June 30, 1942, Midway Airport from July 1, 1942 to January 16, 1980, and at O'Hare Airport since January 17, 1980.[6][7]
References
- ^ "Station: Chicago Midway AP 3SW, IL". U.S. Climate Normals 2020: U.S. Monthly Climate Normals (1991–2020). National Climatic Data Center. Retrieved May 14, 2021.
- ^ a b "NowData – NOAA Online Weather Data". NWS Romeoville, IL. Retrieved May 14, 2021.
- ^ "Top 20 Weather Events of the Century for Chicago and Northeast Illinois 1900–1999". NWS Romeoville, IL. Retrieved June 16, 2014.
- ^ "Chicago Midway AP 3 SW, Illinois". Western Regional Climate Center. Retrieved June 12, 2014.
- ^ "Chicago, IL - Detailed climate information and monthly weather forecast". Weather Atlas. Yu Media Group. Retrieved June 29, 2019.
- ^ "History of the Chicago and Rockford Weather Observation Sites". weather.gov. Retrieved November 9, 2021.
- ^ ThreadEx
- ^ "Station: Chicago Ohare Intl AP, IL". U.S. Climate Normals 2020: U.S. Monthly Climate Normals (1991–2020). National Oceanic and Atmospheric Administration. Retrieved May 14, 2021.
- ^ "Chicago/O'Hare, IL Climate Normals 1961–1990". National Oceanic and Atmospheric Administration. Retrieved July 18, 2020.