West Chicago weather in September: West Chicago, Illinois: normal highs, lows, rain and records for September
West Chicago in September has a normal high of 76°F and a normal low of 54°F, a daily mean of 65°F, falling from 80°F on the 1st to 70°F by the 30th. Measurable precipitation falls on 10 days in a normal September, 3.00 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 24°C and low of 12°C, 76 mm of precipitation in September.
- NOAA stationWest Chicago Dupage Airport
- Station IDUSW00094892
- Location41.91°N 88.25°W
- Elevation754 ft (230 m)
- From the center2 miles
- Population25,469
- Jan 31° 16°
- Feb 35° 19°
- Mar 47° 28°
- Apr 60° 38°
- May 71° 49°
- Jun 81° 59°
- Jul 84° 63°
- Aug 82° 62°
- Sep 76° 54°
- Oct 62° 42°
- Nov 48° 31°
- Dec 35° 21°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is West Chicago in September?
The normal high is 76°F and the normal low 54°F, for a daily mean of 64.6°F. September is 7.3°F cooler than August and 12.4°F warmer than October. September is the 4th warmest month of the year in West Chicago and the 6th wettest. Across the month the normal high falls 10°F, from 80°F on September 1 to 70°F on September 30. From one year to the next September's mean temperature typically moves about 2.7°F either way (NOAA's standard deviation), so roughly two Septembers in three average between 62°F and 67°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 35%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| September 1 | 80°F | 59°F | 35% | 17% |
| September 8 | 78°F | 57°F | 35% | 18% |
| September 15 | 76°F | 54°F | 34% | 18% |
| September 22 | 73°F | 51°F | 34% | 19% |
| September 30 | 70°F | 48°F | 35% | 20% |
Every day of September: normal high, low and chance of precipitation (warmest afternoon September 1, coldest night September 30)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| September 1 | 80°F | 59°F | 35% | 17% | 13 h 10 min |
| September 2 | 80°F | 59°F | 34% | 17% | 13 h 10 min |
| September 3 | 79°F | 58°F | 34% | 17% | 13 h 10 min |
| September 4 | 79°F | 58°F | 34% | 17% | 13 h |
| September 5 | 79°F | 58°F | 34% | 17% | 13 h |
| September 6 | 79°F | 57°F | 34% | 17% | 13 h |
| September 7 | 78°F | 57°F | 34% | 18% | 13 h |
| September 8 | 78°F | 57°F | 35% | 18% | 12 h 50 min |
| September 9 | 78°F | 56°F | 35% | 18% | 12 h 50 min |
| September 10 | 78°F | 56°F | 35% | 18% | 12 h 50 min |
| September 11 | 77°F | 56°F | 34% | 18% | 12 h 40 min |
| September 12 | 77°F | 55°F | 34% | 18% | 12 h 40 min |
| September 13 | 77°F | 55°F | 34% | 18% | 12 h 40 min |
| September 14 | 76°F | 55°F | 34% | 18% | 12 h 40 min |
| September 15 | 76°F | 54°F | 34% | 18% | 12 h 30 min |
| September 16 | 76°F | 54°F | 34% | 18% | 12 h 30 min |
| September 17 | 75°F | 53°F | 34% | 18% | 12 h 30 min |
| September 18 | 75°F | 53°F | 34% | 18% | 12 h 20 min |
| September 19 | 75°F | 52°F | 34% | 18% | 12 h 20 min |
| September 20 | 74°F | 52°F | 34% | 18% | 12 h 20 min |
| September 21 | 74°F | 52°F | 34% | 19% | 12 h 20 min |
| September 22 | 73°F | 51°F | 34% | 19% | 12 h 10 min |
| September 23 | 73°F | 51°F | 34% | 19% | 12 h 10 min |
| September 24 | 73°F | 50°F | 34% | 19% | 12 h 10 min |
| September 25 | 72°F | 50°F | 34% | 19% | 12 h 10 min |
| September 26 | 72°F | 50°F | 34% | 19% | 12 h |
| September 27 | 71°F | 49°F | 34% | 19% | 12 h |
| September 28 | 71°F | 49°F | 34% | 19% | 12 h |
| September 29 | 70°F | 48°F | 34% | 20% | 11 h 50 min |
| September 30 | 70°F | 48°F | 35% | 20% | 11 h 50 min |
- Normal high
- 76°FSeptember average
- Normal low
- 54°FSeptember average
- Precipitation
- 3.00 inmonth total
- Days with precipitation
- 100.01 inch or more
- Days at 90°F or more
- 2
- Daylight
- 13 h 10 min to 11 h 50 minSeptember 1 to September 30
- Days at 70°F or more
- 23
- Days at 80°F or more
- 11
- Sunshine
- 80%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00094892; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in West Chicago in September?
On a given September day the chance of 0.01 inch or more is 34% on average, highest around September 1 (35%). In all, 3.00 in falls on 10 days of a normal September, 1 of them with an inch or more.
In a normal September in West Chicago, 2 days reach 90°F.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00094892.
How humid and windy is West Chicago in September?
At 3 p.m. the normal temperature is 68°F with 50% relative humidity and a dew point of 48°F; at 6 a.m. it is 51°F with 86% humidity. The wind averages 8.5 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. | 51°F | 47°F | 86% | 6.7 mph | 70% |
| 9 a.m. | 60°F | 50°F | 69% | 9.9 mph | 67% |
| noon | 66°F | 49°F | 54% | 11.5 mph | 63% |
| 3 p.m. | 68°F | 48°F | 50% | 11.2 mph | 67% |
| 6 p.m. | 61°F | 48°F | 63% | 8.2 mph | 69% |
| 9 p.m. | 56°F | 49°F | 75% | 7.5 mph | 73% |
Source: NOAA NCEI 1991-2020 hourly normals, station USW00094892. 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 September in West Chicago?
The warmest September temperature on this station's record (since 1997) is 95°F, on September 2, 2008; the coldest is 32°F, on September 24, 2012. The wettest September brought 12.26 in (2008).
The September mean against the 1991-2020 normal of 64.6°F: 2021 68.2°F (+3.6), 2022 65.5°F (+0.9), 2023 66.6°F (+2.0), 2024 67.3°F (+2.7), 2025 67.5°F (+2.9), 2026 68.0°F (+3.4). 6 of 6 ran warmer than normal.
| September | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 68.2°F | +3.6°F | 0.93 in |
| 2022 | 65.5°F | +0.9°F | 2.35 in |
| 2023 | 66.6°F | +2.0°F | 2.77 in |
| 2024 | 67.3°F | +2.7°F | 1.42 in |
| 2025 | 67.5°F | +2.9°F | 0.64 in |
| 2026 | 68.0°F | +3.4°F | 4.74 in |
Source: records: ACIS, station USW00094892; recent months: ACIS, station USW00094892. Records and recent months use complete months only.
How does September in West Chicago compare across Illinois?
Across the 144 places PlainClimate covers in Illinois, September normal highs run from 72°F in Barrington to 84°F in Anna; West Chicago's is 76°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.
Other months and places
- West Chicago in August82°F by day, 62°F at night
- West Chicago in October62°F by day, 42°F at night
- West Chicago through the yearEvery month, frost dates, records and recent years
- Illinois in SeptemberThe statewide normal and the warmest and coolest places
- Anna: Illinois's warmest Septembernormal high 84°F