Carbondale weather in September: Carbondale, Illinois: normal highs, lows, rain and records for September
Carbondale in September has a normal high of 81°F and a normal low of 56°F, a daily mean of 68°F, falling from 85°F on the 1st to 76°F by the 30th. Measurable precipitation falls on 11 days in a normal September, 2.85 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 27°C and low of 13°C, 72 mm of precipitation in September.
- NOAA stationCarbondale Southern Illinois Airport
- Station IDUSW00093810
- Location37.78°N 89.25°W
- Elevation406 ft (124 m)
- From the center4 miles
- Population22,223
- Jan 42° 25°
- Feb 47° 28°
- Mar 57° 36°
- Apr 68° 45°
- May 77° 55°
- Jun 86° 64°
- Jul 88° 68°
- Aug 87° 65°
- Sep 81° 56°
- Oct 70° 45°
- Nov 56° 35°
- Dec 46° 28°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Carbondale in September?
The normal high is 81°F and the normal low 56°F, for a daily mean of 68.3°F. September is 7.7°F cooler than August and 10.9°F warmer than October. September is the 4th warmest month of the year in Carbondale and the 10th wettest. Across the month the normal high falls 9°F, from 85°F on September 1 to 76°F on September 30. From one year to the next September's mean temperature typically moves about 2.9°F either way (NOAA's standard deviation), so roughly two Septembers in three average between 65°F and 71°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 37%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| September 1 | 85°F | 61°F | 37% | 15% |
| September 8 | 83°F | 59°F | 37% | 14% |
| September 15 | 81°F | 56°F | 36% | 14% |
| September 22 | 79°F | 53°F | 35% | 14% |
| September 30 | 76°F | 50°F | 33% | 15% |
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 | 85°F | 61°F | 37% | 15% | 13 h |
| September 2 | 85°F | 61°F | 37% | 15% | 13 h |
| September 3 | 84°F | 60°F | 37% | 14% | 13 h |
| September 4 | 84°F | 60°F | 37% | 14% | 13 h |
| September 5 | 84°F | 60°F | 37% | 14% | 12 h 50 min |
| September 6 | 84°F | 59°F | 37% | 14% | 12 h 50 min |
| September 7 | 83°F | 59°F | 37% | 14% | 12 h 50 min |
| September 8 | 83°F | 59°F | 37% | 14% | 12 h 50 min |
| September 9 | 83°F | 58°F | 37% | 14% | 12 h 40 min |
| September 10 | 83°F | 58°F | 37% | 14% | 12 h 40 min |
| September 11 | 82°F | 58°F | 36% | 14% | 12 h 40 min |
| September 12 | 82°F | 57°F | 36% | 14% | 12 h 40 min |
| September 13 | 82°F | 57°F | 36% | 14% | 12 h 30 min |
| September 14 | 81°F | 56°F | 36% | 14% | 12 h 30 min |
| September 15 | 81°F | 56°F | 36% | 14% | 12 h 30 min |
| September 16 | 81°F | 56°F | 36% | 14% | 12 h 30 min |
| September 17 | 81°F | 55°F | 36% | 14% | 12 h 20 min |
| September 18 | 80°F | 55°F | 36% | 14% | 12 h 20 min |
| September 19 | 80°F | 54°F | 36% | 14% | 12 h 20 min |
| September 20 | 80°F | 54°F | 36% | 14% | 12 h 20 min |
| September 21 | 79°F | 54°F | 35% | 14% | 12 h 10 min |
| September 22 | 79°F | 53°F | 35% | 14% | 12 h 10 min |
| September 23 | 79°F | 53°F | 35% | 14% | 12 h 10 min |
| September 24 | 78°F | 53°F | 35% | 14% | 12 h 10 min |
| September 25 | 78°F | 52°F | 35% | 14% | 12 h 10 min |
| September 26 | 78°F | 52°F | 34% | 14% | 12 h |
| September 27 | 77°F | 51°F | 34% | 14% | 12 h |
| September 28 | 77°F | 51°F | 34% | 14% | 12 h |
| September 29 | 77°F | 51°F | 34% | 15% | 12 h |
| September 30 | 76°F | 50°F | 33% | 15% | 11 h 50 min |
- Normal high
- 81°FSeptember average
- Normal low
- 56°FSeptember average
- Precipitation
- 2.85 inmonth total
- Days with precipitation
- 110.01 inch or more
- Days at 90°F or more
- 4
- Daylight
- 13 h to 11 h 50 minSeptember 1 to September 30
- Days at 70°F or more
- 28
- Days at 80°F or more
- 19
- Sunshine
- 81%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00093810; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Carbondale in September?
On a given September day the chance of 0.01 inch or more is 36% on average, highest around September 1 (37%). In all, 2.85 in falls on 11 days of a normal September, 1 of them with an inch or more.
In a normal September in Carbondale, 4 days reach 90°F.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00093810.
What are the records for September in Carbondale?
The warmest September temperature on Carbondale's official record (since 1898) is 108°F, on September 6, 1925; the coldest is 20°F, on September 30, 1899. The wettest September brought 9.52 in (1993).
The September mean against the 1991-2020 normal of 68.3°F: 2021 70.5°F (+2.3), 2022 68.2°F (−0.1), 2023 70.5°F (+2.2), 2024 71.0°F (+2.7), 2025 71.8°F (+3.5), 2026 77.0°F (+8.7). 5 of 6 ran warmer than normal.
| September | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 70.5°F | +2.3°F | 6.48 in |
| 2022 | 68.2°F | −0.1°F | 0.69 in |
| 2023 | 70.5°F | +2.2°F | 0.64 in |
| 2024 | 71.0°F | +2.7°F | – |
| 2025 | 71.8°F | +3.5°F | 2.33 in |
| 2026 | 77.0°F | +8.7°F | – |
Source: records: ACIS, NWS threaded record MDHthr; recent months: ACIS, station USW00093810. Records and recent months use complete months only.
How does September in Carbondale 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; Carbondale's is 81°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.