Chicago weather in October: Chicago, Illinois: normal highs, lows, rain and records for October
Chicago in October has a normal high of 63°F and a normal low of 45°F, a daily mean of 54°F, falling from 69°F on the 1st to 56°F by the 31st. Measurable precipitation falls on 11 days in a normal October, 3.43 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 17°C and low of 7°C, 87 mm of precipitation and 1 cm of snow in October.
- NOAA stationChicago O'Hare International Airport
- Station IDUSW00094846
- Location41.99°N 87.93°W
- Elevation658 ft (201 m)
- From the center17 miles
- Population2,721,308
- Jan 32° 19°
- Feb 36° 22°
- Mar 47° 31°
- Apr 59° 40°
- May 71° 51°
- Jun 80° 61°
- Jul 85° 66°
- Aug 83° 65°
- Sep 76° 57°
- Oct 63° 45°
- Nov 48° 34°
- Dec 37° 24°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Chicago in October?
The normal high is 63°F and the normal low 45°F, for a daily mean of 54.0°F. October is 12.3°F cooler than September and 12.7°F warmer than November. October is the 6th warmest month of the year in Chicago and the 6th wettest. Across the month the normal high falls 13°F, from 69°F on October 1 to 56°F on October 31. From one year to the next October's mean temperature typically moves about 2.5°F either way (NOAA's standard deviation), so roughly two Octobers in three average between 52°F and 57°F.
Bars above: each day's normal high to low. Columns below: the chance of 0.01 inch or more of precipitation that day, on a scale of 0 to 100% (highest 34%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| October 1 | 69°F | 51°F | 31% | 20% |
| October 8 | 66°F | 48°F | 32% | 20% |
| October 15 | 63°F | 46°F | 33% | 20% |
| October 22 | 60°F | 43°F | 34% | 19% |
| October 31 | 56°F | 40°F | 34% | 18% |
Every day of October: normal high, low and chance of precipitation (warmest afternoon October 1, coldest night October 31)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| October 1 | 69°F | 51°F | 31% | 20% | 11 h 50 min |
| October 2 | 69°F | 51°F | 32% | 20% | 11 h 50 min |
| October 3 | 69°F | 50°F | 32% | 20% | 11 h 40 min |
| October 4 | 68°F | 50°F | 32% | 20% | 11 h 40 min |
| October 5 | 68°F | 49°F | 32% | 20% | 11 h 40 min |
| October 6 | 67°F | 49°F | 32% | 20% | 11 h 30 min |
| October 7 | 67°F | 49°F | 32% | 20% | 11 h 30 min |
| October 8 | 66°F | 48°F | 32% | 20% | 11 h 30 min |
| October 9 | 66°F | 48°F | 32% | 20% | 11 h 30 min |
| October 10 | 65°F | 48°F | 32% | 20% | 11 h 20 min |
| October 11 | 65°F | 47°F | 33% | 20% | 11 h 20 min |
| October 12 | 65°F | 47°F | 33% | 20% | 11 h 20 min |
| October 13 | 64°F | 46°F | 33% | 20% | 11 h 10 min |
| October 14 | 64°F | 46°F | 33% | 20% | 11 h 10 min |
| October 15 | 63°F | 46°F | 33% | 20% | 11 h 10 min |
| October 16 | 63°F | 45°F | 33% | 20% | 11 h 10 min |
| October 17 | 62°F | 45°F | 33% | 19% | 11 h |
| October 18 | 62°F | 45°F | 33% | 19% | 11 h |
| October 19 | 61°F | 44°F | 34% | 19% | 11 h |
| October 20 | 61°F | 44°F | 34% | 19% | 11 h |
| October 21 | 61°F | 44°F | 34% | 19% | 10 h 50 min |
| October 22 | 60°F | 43°F | 34% | 19% | 10 h 50 min |
| October 23 | 60°F | 43°F | 34% | 19% | 10 h 50 min |
| October 24 | 59°F | 43°F | 34% | 19% | 10 h 40 min |
| October 25 | 59°F | 42°F | 34% | 19% | 10 h 40 min |
| October 26 | 58°F | 42°F | 34% | 19% | 10 h 40 min |
| October 27 | 58°F | 42°F | 34% | 19% | 10 h 40 min |
| October 28 | 57°F | 41°F | 34% | 18% | 10 h 30 min |
| October 29 | 57°F | 41°F | 34% | 18% | 10 h 30 min |
| October 30 | 56°F | 40°F | 34% | 18% | 10 h 30 min |
| October 31 | 56°F | 40°F | 34% | 18% | 10 h 30 min |
- Normal high
- 63°FOctober average
- Normal low
- 45°FOctober average
- Precipitation
- 3.43 inmonth total
- Days with precipitation
- 110.01 inch or more
- Snowfall
- 0.2 inmonth total
- Nights at 32°F or colder
- 3
- Daylight
- 11 h 50 min to 10 h 30 minOctober 1 to October 31
- Days at 70°F or more
- 8
- Days at 80°F or more
- 2
- Sunshine
- 70%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00094846; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain or snow in Chicago in October?
On a given October day the chance of 0.01 inch or more is 33% on average, highest around October 24 (34%). In all, 3.43 in falls on 11 days of a normal October, 1 of them with an inch or more.
In a normal October in Chicago, 3 nights fall to freezing and snowfall averages 0.2 inches.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00094846.
How humid and windy is Chicago in October?
At 3 p.m. the normal temperature is 53°F with 55% relative humidity and a dew point of 37°F; at 6 a.m. it is 43°F with 79% humidity. The wind averages 10.4 mph, most often from the west-southwest in the afternoon. A dew point under 50°F feels dry.
| Time | Temperature | Dew point | Humidity | Wind | Clear or few clouds |
|---|---|---|---|---|---|
| 6 a.m. | 43°F | 36°F | 79% | 9.2 mph | 31% |
| 9 a.m. | 47°F | 37°F | 69% | 11.4 mph | 31% |
| noon | 52°F | 37°F | 57% | 12.2 mph | 23% |
| 3 p.m. | 53°F | 37°F | 55% | 12.3 mph | – |
| 6 p.m. | 49°F | 37°F | 65% | 9.9 mph | 25% |
| 9 p.m. | 46°F | 37°F | 70% | 9.7 mph | 33% |
Source: NOAA NCEI 1991-2020 hourly normals, station USW00094846. Hourly normals exist only for NOAA's first-order stations; a dash where NOAA publishes no value for that hour (the sky at some hours).
What are the records for October in Chicago?
The warmest October temperature on Chicago's official record (since 1872) is 94°F, on October 6, 1963; the coldest is 14°F, on October 25, 1887. The wettest October brought 12.06 in (1954); the snowiest, 6.3 inches (1989).
The October mean against the 1991-2020 normal of 54.0°F: 2021 59.7°F (+5.7), 2022 54.0°F (at normal), 2023 57.1°F (+3.1), 2024 59.7°F (+5.7), 2025 58.1°F (+4.1). 4 of 5 ran warmer than normal.
| October | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 59.7°F | +5.7°F | 5.77 in |
| 2022 | 54.0°F | at normal | 1.66 in |
| 2023 | 57.1°F | +3.1°F | 2.28 in |
| 2024 | 59.7°F | +5.7°F | 1.18 in |
| 2025 | 58.1°F | +4.1°F | 2.67 in |
Source: records: ACIS, NWS threaded record ORDthr; recent months: ACIS, station USW00094846. Records and recent months use complete months only.
How does October in Chicago compare across Illinois?
Across the 144 places PlainClimate covers in Illinois, October normal highs run from 60°F in Barrington to 73°F in Anna; Chicago's is 63°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.