Oshkosh weather in September

In September, Oshkosh sees average daytime highs of 69°F and overnight lows near 56°F, with 2.9 in of rain across 9.3 wet days and about 12.3 hours of daylight. It is the 4th-warmest and 7th-wettest month of the year here.

Highs ease over the month, from about 74°F in the first days to 64°F by the end. The sky is clear or mostly clear about 38% of the time in September, and the air most often feels dry.

Daylight stretches from about 13 h 06 min at the start of September to 11 h 36 min by month's end. Set against the rest of the year, September is Oshkosh's 2nd-clearest and 9th-windiest month. For the whole year in context, see Oshkosh's year-round climate.

Daytime high
69°
4th warmest
Overnight low
56°
9th coldest
Rainfall
2.9 in
9.3 wet days
Daylight
12 h 18 min
5:40 AM – 5:57 PM
Cloud cover
53%
2nd clearest
Wind
9 mph
9th windiest
Solar energy
4.08 kWh/m²
Travel score
6.6
out of 10

Oshkosh is city in and county seat of Winnebago County, Wisconsin, United States.

Density
924/km²
people per km²
Founded
1818

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 74°F in the first days to 64°F by the end.

A typical September day in Oshkosh reaches about 69°F in the afternoon and slips back to 56°F overnight — a 14°F spread between the day's warmth and the night's chill. On most days the high lands between 59°F and 79°F. Set against its neighbours, September runs about 7°F cooler than August and about 13°F warmer than October.

40°60°80°151015202530
Avg high (°F)Avg low (°F)
17461
27460
37460
47460
57360
67359
77359
87258
97258
107158
117157
127157
137057
147056
157056
166956
176955
186855
196854
206854
216754
226753
236653
246652
256552
266551
276551
286451
296450
306350

How September really feels in Oshkosh

Once humidity and wind are folded in, September averages 0 days that feel above 90°F and 0 that feel at or below 32°F — the comfort signal a plain temperature reading hides.

Days feeling ≥ 90°F
0
heat index over the day's high
Days feeling ≤ 32°F
0
wind chill below the day's low

September sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Oshkosh weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 7th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan25° / 14°1.57.86.99.10.0
Feb28° / 16°1.36.65.510.20.0
Mar38° / 25°2.38.74.711.60.1
Apr51° / 37°3.310.92.413.22.4
May64° / 50°3.410.9014.55.5
Jun74° / 61°3.710.6015.26.7
Jul79° / 65°3.210.10156.8
Aug77° / 63°3.410.1013.87.0
Sep69° / 56°2.99.3012.36.6
Oct56° / 44°2.99.90.310.83.8
Nov42° / 32°2.18.32.49.40.6
Dec31° / 20°1.77.15.48.80.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 38% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 15% of September, with mostly cloudy or overcast conditions the remaining 48%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
15743
25743
35743
45842
55743
65743
75644
85545
95446
105446
115347
125248
135248
145149
155149
165149
175050
185050
195050
205149
215149
225149
235050
245050
255050
264951
275050
285050
295050
304951

Chance of precipitation in September

Any precipitation

Oshkosh gets around 2.9 in of rain over 9.3 wet days in September. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 31% and peaks near 34% on the wettest days.

0%10%20%30%40%151015202530
Rain chance (%)
129
229
329
429
528
628
728
828
929
1029
1129
1230
1330
1431
1531
1632
1732
1832
1932
2033
2133
2233
2334
2434
2534
2634
2734
2834
2934
3033

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

Most of September feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, September lands in the dry band about 52% of days. Sticky, muggy-or-worse air turns up on roughly 11% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1262524214
2282524203
3292523193
4312523183
5332522172
6352522162
7372521162
8382421151
9402420141
10422420141
11432419131
12452419121
13462418111
14482418100
15492417100
1651231790
1753231680
1855221580
1957221470
2060211360
2161211260
2264201150
2365191150
2468181040
257017940
267316830
277415830
287614730
297913620
308012620

Wind in September

Winds average 9 mph in September.

Across September, daily wind ranges from about 8 mph on the calmest days to 10 mph at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (mph)Feels
18light breeze
28light breeze
38light breeze
49light breeze
59light breeze
69light breeze
79light breeze
89light breeze
99light breeze
109light breeze
119light breeze
129light breeze
139light breeze
149light breeze
159light breeze
169light breeze
179light breeze
189light breeze
199light breeze
209light breeze
2110light breeze
2210light breeze
2310light breeze
2410light breeze
2510light breeze
2610light breeze
2710light breeze
2810light breeze
2910light breeze
3010light breeze

Sunrise & sunset in September

DaylightNight

Daylight runs from about 13 h 06 min at the start of September to 11 h 36 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 90 minutes over September. Sunrise moves from 5:22 AM to 5:56 AM, and sunset from 6:26 PM to 5:31 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.15:226:26
213.05:236:24
313.05:246:22
412.95:256:20
512.95:276:18
612.85:286:17
712.85:296:15
812.75:306:13
912.75:316:11
1012.65:326:09
1112.65:346:07
1212.55:356:05
1312.55:366:03
1412.45:376:01
1512.45:385:59
1612.35:405:57
1712.25:415:56
1812.25:425:54
1912.15:435:52
2012.15:445:50
2112.05:455:48
2212.05:475:46
2311.95:485:44
2411.95:495:42
2511.85:505:40
2611.85:515:38
2711.75:535:36
2811.75:545:34
2911.65:555:33
3011.65:565:31

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.08 kWh/m².

For context, solar energy here swings from a low near 1.55 kWh/m² to a high of 6.14 kWh/m² in June across the year — September's 4.08 kWh/m² falls in the middle.

024151015202530
Solar energy (kWh/m²)Level
14.7Bright
24.7Bright
34.6Bright
44.6Bright
54.5Bright
64.5Bright
74.4Bright
84.4Bright
94.3Bright
104.3Bright
114.2Bright
124.2Bright
134.1Bright
144.1Bright
154.0Bright
164.0Bright
174.0Moderate
183.9Moderate
193.9Moderate
203.9Moderate
213.8Moderate
223.8Moderate
233.7Moderate
243.7Moderate
253.7Moderate
263.6Moderate
273.6Moderate
283.5Moderate
293.5Moderate
303.5Moderate
Planning a trip in September

Is September a good time to visit Oshkosh?

Our two travel scores rate September for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

6.6
Sightseeing
4th-best month of the year
3.8
Beach & pool
4th-best month of the year

September is a reasonable time to visit Oshkosh for sightseeing.

What to pack for Oshkosh in September

From September's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In September, Oshkosh sees daytime highs around 69°F and nights near 56°F. Worth packing: rain gear. About 9 days see rain.

rain gear

UV index in Oshkosh in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 5 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Oshkosh peaks around June 18 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 20 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJun 18UV 9Dec 20UV 1
UV index (midday)Level
Jan2Low
Feb2Moderate
Mar4Moderate
Apr5High
May8Very high
Jun9Very high
Jul8Very high
Aug7Very high
Sep5High
Oct3Moderate
Nov2Low
Dec1Low
Location & terrain

Where is Oshkosh?

Oshkosh sits at 44.0°N, 88.5°W, 768 ft above sea level, in United States. The nearest listed city is Neenah, 12 mi away.

Topography around Oshkosh

How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Oshkosh.

Within 2 miles, the terrain around Oshkosh has only modest variations in elevation — a maximum elevation change of 148 ft around an average of 758 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 318 ft; within 50 miles, only modest variations in elevation — a maximum elevation change of 768 ft.

The land around Oshkosh is covered by artificial surfaces (44%), trees (21%) and water (21%) within 2 miles, water (40%) and cropland (30%) within 10 miles, and cropland (45%) and trees (30%) within 50 miles.

2 miles
148 ft
10 miles
318 ft
50 miles
768 ft
treesgrasslandcroplandartificial surfacesbare terrainwater
September weather nearby: Neenah 12 mi · Menasha 13 mi · Appleton 17 mi · Fond du Lac 18 mi · Kaukauna 22 mi · De Pere 38 mi · Ashwaubenon 39 mi · Beaver Dam 42 mi

United States travel facts

Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 100% of US
price level, 2025
GDP per capita
$90,027
2025
Happiness
6.8 / 10
World Happiness, 2025
Safe drinking water
98%
of population, 2024
Homicide rate
5.8
per 100k, 2023
Road deaths
12.7
per 100k/yr, 2019
Income group
High
World Bank
Religion
Protestant 47%unaffiliated 23%Roman Catholic 21%Jewish 2%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Oshkosh (44.0247°, -88.5426°, elevation 768 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).