Yorkville weather in September

In September, Yorkville sees average daytime highs of 74°F and overnight lows near 55°F, with 3.1 in of rain across 8.5 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 78°F in the first days to 70°F by the end. The sky is clear or mostly clear about 43% of the time in September, and the air most often feels dry.

Daylight stretches from about 13 hours at the start of September to 11 h 36 min by month's end. Set against the rest of the year, September is Yorkville's 1st-clearest and 9th-windiest month. For the whole year in context, see Yorkville's year-round climate.

Daytime high
74°
4th warmest
Overnight low
55°
9th coldest
Rainfall
3.1 in
8.5 wet days
Daylight
12 h 18 min
5:40 AM – 5:56 PM
Cloud cover
49%
1st clearest
Wind
7 mph
9th windiest
Solar energy
4.46 kWh/m²
Travel score
7.1
out of 10

Yorkville is city in and county seat of Kendall County, Illinois, United States.

Density
348/km²
people per km²
Founded
1833

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 78°F in the first days to 70°F by the end.

A typical September day in Yorkville reaches about 74°F in the afternoon and slips back to 55°F overnight — a 19°F spread between the day's warmth and the night's chill. On most days the high lands between 64°F and 84°F. Set against its neighbours, September runs about 6°F cooler than August and about 13°F warmer than October.

40°60°80°151015202530
Avg high (°F)Avg low (°F)
17960
27960
37860
47859
57859
67859
77758
87758
97758
107657
117657
127656
137556
147556
157555
167455
177454
187454
197354
207353
217253
227252
237252
247151
257151
267051
277050
287050
296949
306949

How September really feels in Yorkville

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.

Yorkville 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
Jan30° / 17°2.17.95.79.30.0
Feb35° / 20°1.974.610.30.0
Mar47° / 30°2.69.62.811.71.5
Apr59° / 40°4.512.30.913.14.3
May70° / 51°4.712.7014.36.0
Jun79° / 61°4.211.80156.3
Jul82° / 65°3.710.9014.76.1
Aug80° / 63°3.59.9013.76.6
Sep74° / 55°3.18.5012.37.1
Oct62° / 43°3.29.20.110.95.3
Nov47° / 32°2.58.11.39.71.7
Dec36° / 22°2.27.94.390.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 43% of the time in September, the clearest month of the year.

Beyond those clear spells, partly cloudy skies cover about 14% of September, with mostly cloudy or overcast conditions the remaining 43%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
15941
26139
36139
46139
56139
66139
76139
86139
96139
106040
115941
125941
135842
145743
155644
165644
175545
185545
195545
205446
215446
225446
235446
245446
255347
265446
275446
285347
295347
305347

Chance of precipitation in September

Any precipitation

Yorkville gets around 3.1 in of rain over 8.5 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 29% and peaks near 30% on the wettest days.

0%10%20%30%40%151015202530
Rain chance (%)
129
229
329
428
528
628
728
828
929
1029
1129
1229
1329
1430
1530
1630
1730
1830
1929
2029
2129
2229
2329
2430
2530
2630
2730
2830
2929
3029

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 49% of days. Sticky, muggy-or-worse air turns up on roughly 13% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1212822218
2222922207
3242921197
4262921186
5283020175
6303020165
7322920154
8342919144
9362819143
10382819133
11402718132
12422618122
13442517122
14462417111
15482316111
16502316101
17522215101
1855211491
1957201490
2059201380
2161191280
2264181170
2365181160
2467171060
256917950
267016950
277216840
287315840
297415740
307614730

Wind in September

Winds average 7 mph in September.

Across September, daily wind ranges from about 7 mph on the calmest days to 8 mph at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (mph)Feels
17calm
27calm
37calm
47calm
57calm
67calm
77calm
87calm
97calm
107calm
117calm
127calm
137calm
147calm
157calm
167calm
177calm
187light breeze
198light breeze
208light breeze
218light breeze
228light breeze
238light breeze
248light breeze
258light breeze
268light breeze
278light breeze
288light breeze
298light breeze
308light breeze

Sunrise & sunset in September

DaylightNight

Daylight runs from about 13 hours 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 84 minutes over September. Sunrise moves from 5:24 AM to 5:55 AM, and sunset from 6:23 PM to 5:31 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.05:246:23
212.95:256:21
312.95:266:19
412.85:276:18
512.85:286:16
612.75:296:14
712.75:306:12
812.75:316:11
912.65:326:09
1012.65:346:07
1112.55:356:05
1212.55:366:04
1312.45:376:02
1412.45:386:00
1512.35:395:58
1612.35:405:56
1712.25:415:55
1812.25:425:53
1912.15:435:51
2012.15:445:49
2112.05:455:47
2212.05:465:46
2311.95:475:44
2411.95:485:42
2511.85:495:40
2611.85:515:38
2711.75:525:37
2811.75:535:35
2911.75:545:33
3011.65:555:31

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.46 kWh/m².

For context, solar energy here swings from a low near 1.68 kWh/m² to a high of 6.28 kWh/m² in June across the year — September's 4.46 kWh/m² falls in the middle.

024151015202530
Solar energy (kWh/m²)Level
15.0Bright
25.0Bright
34.9Bright
44.9Bright
54.9Bright
64.8Bright
74.8Bright
84.8Bright
94.7Bright
104.7Bright
114.6Bright
124.6Bright
134.5Bright
144.5Bright
154.5Bright
164.4Bright
174.4Bright
184.3Bright
194.3Bright
204.3Bright
214.2Bright
224.2Bright
234.1Bright
244.1Bright
254.0Bright
264.0Moderate
274.0Moderate
283.9Moderate
293.9Moderate
303.8Moderate
Planning a trip in September

Is September a good time to visit Yorkville?

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

7.1
Sightseeing
1st-best month of the year
5.6
Beach & pool
4th-best month of the year

September is one of the better times to visit Yorkville for general sightseeing.

What to pack for Yorkville in September

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

In September, Yorkville sees daytime highs around 74°F and nights near 55°F. Worth packing: light clothes and rain gear. About 9 days see rain.

light clothesrain gear

UV index in Yorkville in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 6 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Yorkville peaks around June 20 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 19 at about 2 (low).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highHighModerateLowJun 20UV 9Dec 19UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar5Moderate
Apr6High
May7Very high
Jun9Very high
Jul8Very high
Aug8Very high
Sep6High
Oct3Moderate
Nov2Moderate
Dec2Low

Air quality in Yorkville in September

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where September falls, not just the annual average.

Air quality in Yorkville is worst in July — around 17 µg/m³ PM2.5 (moderate), about 1.9× the cleanest month (October, 9 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

01020JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodJul 1817 µg/m³Oct 229 µg/m³
PM2.5 (µg/m³)Level
Jan12Moderate
Feb15Moderate
Mar16Moderate
Apr14Moderate
May15Moderate
Jun16Moderate
Jul17Moderate
Aug16Moderate
Sep13Moderate
Oct9Good
Nov10Good
Dec11Good
Location & terrain

Where is Yorkville?

Yorkville sits at 41.6°N, 88.4°W, 607 ft above sea level, in United States. The nearest listed city is Oswego, 5.6 mi away.

Topography around Yorkville

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

Within 2 miles, the terrain around Yorkville has only modest variations in elevation — a maximum elevation change of 276 ft around an average of 653 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 751 ft.

The land around Yorkville is covered by trees (37%), cropland (24%) and grassland (21%) within 2 miles, cropland (64%) within 10 miles, and cropland (58%) within 50 miles.

2 miles
276 ft
10 miles
318 ft
50 miles
751 ft
treesgrasslandcroplandartificial surfaceswater
September weather nearby: Oswego 5.6 mi · Montgomery 8.1 mi · Aurora 11 mi · Plainfield 12 mi · North Aurora 13 mi · Shorewood 15 mi · Batavia 16 mi · Naperville 19 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 Yorkville (41.6411°, -88.4473°, elevation 607 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. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).