Oshkosh weather in September: Oshkosh, Wisconsin: normal highs, lows, rain and records for September
Oshkosh in September has a normal high of 72°F and a normal low of 51°F, a daily mean of 62°F, falling from 77°F on the 1st to 66°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 22°C and low of 11°C, 76 mm of precipitation in September.
- NOAA stationOshkosh Wittman Airport
- Station IDUSW00094855
- Location43.98°N 88.56°W
- Elevation782 ft (238 m)
- Population67,242
- Jan 26° 11°
- Feb 30° 14°
- Mar 42° 24°
- Apr 55° 36°
- May 67° 47°
- Jun 77° 57°
- Jul 81° 61°
- Aug 79° 60°
- Sep 72° 51°
- Oct 59° 40°
- Nov 44° 29°
- Dec 32° 18°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Oshkosh in September?
The normal high is 72°F and the normal low 51°F, for a daily mean of 61.7°F. September is 7.7°F cooler than August and 12.4°F warmer than October. September is the 4th warmest month of the year in Oshkosh and the 5th wettest. Across the month the normal high falls 11°F, from 77°F on September 1 to 66°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 59°F and 64°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 36%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| September 1 | 77°F | 56°F | 34% | 20% |
| September 8 | 75°F | 54°F | 35% | 20% |
| September 15 | 73°F | 52°F | 35% | 20% |
| September 22 | 70°F | 49°F | 35% | 20% |
| September 30 | 66°F | 46°F | 36% | 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 | 77°F | 56°F | 34% | 20% | 13 h 20 min |
| September 2 | 77°F | 56°F | 34% | 20% | 13 h 10 min |
| September 3 | 76°F | 56°F | 34% | 20% | 13 h 10 min |
| September 4 | 76°F | 55°F | 34% | 20% | 13 h 10 min |
| September 5 | 76°F | 55°F | 34% | 20% | 13 h |
| September 6 | 75°F | 55°F | 34% | 20% | 13 h |
| September 7 | 75°F | 54°F | 35% | 20% | 13 h |
| September 8 | 75°F | 54°F | 35% | 20% | 13 h |
| September 9 | 75°F | 54°F | 35% | 20% | 12 h 50 min |
| September 10 | 74°F | 53°F | 35% | 20% | 12 h 50 min |
| September 11 | 74°F | 53°F | 35% | 20% | 12 h 50 min |
| September 12 | 74°F | 53°F | 35% | 20% | 12 h 40 min |
| September 13 | 73°F | 52°F | 35% | 20% | 12 h 40 min |
| September 14 | 73°F | 52°F | 35% | 20% | 12 h 40 min |
| September 15 | 73°F | 52°F | 35% | 20% | 12 h 40 min |
| September 16 | 72°F | 51°F | 35% | 20% | 12 h 30 min |
| September 17 | 72°F | 51°F | 35% | 20% | 12 h 30 min |
| September 18 | 71°F | 51°F | 35% | 20% | 12 h 30 min |
| September 19 | 71°F | 50°F | 35% | 20% | 12 h 20 min |
| September 20 | 71°F | 50°F | 35% | 20% | 12 h 20 min |
| September 21 | 70°F | 49°F | 35% | 20% | 12 h 20 min |
| September 22 | 70°F | 49°F | 35% | 20% | 12 h 10 min |
| September 23 | 69°F | 49°F | 35% | 20% | 12 h 10 min |
| September 24 | 69°F | 48°F | 35% | 20% | 12 h 10 min |
| September 25 | 68°F | 48°F | 35% | 20% | 12 h 10 min |
| September 26 | 68°F | 48°F | 35% | 20% | 12 h |
| September 27 | 68°F | 47°F | 36% | 20% | 12 h |
| September 28 | 67°F | 47°F | 36% | 20% | 12 h |
| September 29 | 67°F | 46°F | 36% | 20% | 11 h 50 min |
| September 30 | 66°F | 46°F | 36% | 20% | 11 h 50 min |
- Normal high
- 72°FSeptember average
- Normal low
- 51°FSeptember average
- Precipitation
- 3.00 inmonth total
- Days with precipitation
- 100.01 inch or more
- Daylight
- 13 h 20 min to 11 h 50 minSeptember 1 to September 30
- Days at 70°F or more
- 19
- Days at 80°F or more
- 7
- Sunshine
- 77%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00094855; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Oshkosh in September?
On a given September day the chance of 0.01 inch or more is 35% on average, highest around September 29 (36%). In all, 3.00 in falls on 10 days of a normal September, 1 of them with an inch or more.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00094855.
What are the records for September in Oshkosh?
The warmest September temperature on this station's record (since 1996) is 94°F, on September 3, 2023; the coldest is 30°F, on September 19, 2012. The wettest September brought 7.20 in (2026).
The September mean against the 1991-2020 normal of 61.7°F: 2021 63.7°F (+2.0), 2022 61.8°F (+0.1), 2023 65.8°F (+4.0), 2024 66.3°F (+4.5), 2025 63.5°F (+1.8), 2026 64.3°F (+2.6). 6 of 6 ran warmer than normal.
| September | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 63.7°F | +2.0°F | 0.95 in |
| 2022 | 61.8°F | +0.1°F | 4.98 in |
| 2023 | 65.8°F | +4.0°F | 1.56 in |
| 2024 | 66.3°F | +4.5°F | 1.20 in |
| 2025 | 63.5°F | +1.8°F | 1.75 in |
| 2026 | 64.3°F | +2.6°F | 7.20 in |
Source: records: ACIS, station USW00094855; recent months: ACIS, station USW00094855. Records and recent months use complete months only.
How does September in Oshkosh compare across Wisconsin?
Across the 165 places PlainClimate covers in Wisconsin, September normal highs run from 64°F in Laona to 77°F in West Allis; Oshkosh's is 72°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.