Climate averages 1991–2020
Bolingbrook weather
in September.
A warm, moderately wet month: the 4th warmest and the 6th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
September is a warm month in Bolingbrook: daytime highs average 23.2°C and nights cool to about 14.3°C. By daytime temperature it is the 4th warmest of the 12 months.
Expect about 74 mm of rain on roughly 8 days, which makes September a moderately wet month (the 6th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 31 min on an average September day.
The nearest other city in this atlas is Naperville (12 km away). In September its highs average 23.1°C, about as warm as Bolingbrook, with 77 mm of rain.
Among the 498 cities listed in the United States, Bolingbrook ranks joint 393rd of 498 for the warmest September highs and joint 241st of 498 for the driest September (rainfall, lowest first). The mean September high of those 498 cities is 26.9°C; Bolingbrook is 3.7°C cooler than that mean.
From September to October, average highs fall by 6.9°C to 16.3°C, and monthly rainfall rises from 74 mm to 79 mm.
The annual picture
September in context
Monthly precipitation
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Bolingbrook climate table
| Month | Average highHigh / low | Average low | Precipitation mm/month | Wet days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | -0.7°C-8.5°C | -8.5°C | 54 | 8.3 | 9.510 h |
| February | 1.8°C-6.9°C | -6.9°C | 50 | 7.2 | 10.611 h |
| March | 8.0°C-1.5°C | -1.5°C | 68 | 10.1 | 11.912 h |
| April | 14.6°C4.3°C | 4.3°C | 112 | 12.2 | 13.313 h |
| May | 20.6°C10.6°C | 10.6°C | 113 | 12.7 | 14.515 h |
| June | 25.7°C16.2°C | 16.2°C | 106 | 12.1 | 15.115 h |
| July | 27.8°C18.8°C | 18.8°C | 95 | 11.3 | 14.915 h |
| August | 26.8°C18.2°C | 18.2°C | 95 | 10.9 | 13.914 h |
| September, selected | 23.2°C14.3°C | 14.3°C | 74 | 8.2 | 12.513 h |
| October | 16.3°C7.9°C | 7.9°C | 79 | 9.0 | 11.111 h |
| November | 8.6°C1.0°C | 1.0°C | 64 | 8.3 | 9.910 h |
| December | 2.1°C-4.8°C | -4.8°C | 55 | 8.0 | 9.29 h |
Precipitation (rain or snow, as water) is the average of the 30 separate monthly totals. A wet day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
September in nearby cities
- Naperville in SeptemberUnited States · 12 kmHigh 23.1°C · Low 14.3°C · 77 mm rain
- Joliet in SeptemberUnited States · 19 kmHigh 23.8°C · Low 14.5°C · 75 mm rain
- Aurora (Illinois), United States in SeptemberUnited States · 22 kmHigh 23.2°C · Low 14.1°C · 77 mm rain
- Cicero in SeptemberUnited States · 31 kmHigh 23.1°C · Low 15.2°C · 75 mm rain
- Schaumburg in SeptemberUnited States · 37 kmHigh 22.9°C · Low 14.2°C · 75 mm rain
- Chicago in SeptemberUnited States · 39 kmHigh 22.7°C · Low 15.8°C · 75 mm rain
- Elgin in SeptemberUnited States · 42 kmHigh 23.1°C · Low 14.3°C · 78 mm rain
- Arlington Heights in SeptemberUnited States · 44 kmHigh 22.7°C · Low 15.1°C · 75 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Bolingbrook) is explained once on the Bolingbrook year overview and on the Sources, method and limits page.