Marion weather in October

In October, Marion sees average daytime highs of 69°F and overnight lows near 50°F, with 3.5 in of rain across 7.6 wet days and about 11 hours of daylight. It is the 6th-warmest and 6th-wettest month of the year here.

Highs ease over the month, from about 75°F in the first days to 63°F by the end. The sky is clear or mostly clear about 47% of the time in October, and the air most often feels dry.

Daylight stretches from about 11 h 36 min at the start of October to 10 h 24 min by month's end. Set against the rest of the year, October is Marion's 2nd-clearest and 7th-windiest month. For the whole year in context, see Marion's year-round climate.

Daytime high
69°
6th warmest
Overnight low
50°
7th coldest
Rainfall
3.5 in
7.6 wet days
Daylight
11 hours
6:11 AM – 5:11 PM
Cloud cover
48%
2nd clearest
Wind
7 mph
7th windiest
Solar energy
3.59 kWh/m²
Travel score
6.9
out of 10

Marion is city in and the county seat of Williamson County, Illinois, United States.

Density
412/km²
people per km²
Founded
1839

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

Temperature in October

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 75°F in the first days to 63°F by the end.

A typical October day in Marion reaches about 69°F in the afternoon and slips back to 50°F overnight — a 19°F spread between the day's warmth and the night's chill. On most days the high lands between 57°F and 81°F. Set against its neighbours, October runs about 12°F cooler than September and about 13°F warmer than November.

40°60°80°151015202531
Avg high (°F)Avg low (°F)
17555
27555
37555
47454
57454
67453
77353
87353
97252
107252
117151
127151
137051
147050
156950
166950
176949
186849
196749
206748
216748
226648
236647
246547
256547
266446
276446
286446
296345
306345
316245

How October really feels in Marion

Once humidity and wind are folded in, October 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

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

Marion weather by month

How October compares with the rest of the year at a glance. October is the 6th-warmest and 6th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan42° / 28°3.492.39.70.3
Feb47° / 31°3.18.12.310.51.5
Mar57° / 39°4.211.40.911.74.0
Apr68° / 49°5.011.4012.96.0
May76° / 60°4.612.60146.3
Jun85° / 68°3.610.6014.65.2
Jul88° / 72°3.510.2014.34.5
Aug87° / 69°2.88.1013.55.1
Sep81° / 61°2.97.5012.36.9
Oct69° / 50°3.57.60116.9
Nov56° / 39°3.88.70.5103.9
Dec46° / 31°3.38.91.89.41.2

Cloud cover in October

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 47% of the time in October.

Beyond those clear spells, partly cloudy skies cover about 13% of October, with mostly cloudy or overcast conditions the remaining 41%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
16733
26634
36634
46634
56535
66436
76337
86238
96238
106139
116139
126139
136139
146139
156040
166040
175941
185941
195941
205941
215842
225743
235743
245644
255545
265446
275347
285248
295149
305149
315050

Chance of precipitation in October

Any precipitation

Marion gets around 3.5 in of rain over 7.6 wet days in October. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 25% and peaks near 29% on the wettest days. The odds climb toward the end of the month.

0%10%20%30%40%151015202531
Rain chance (%)
120
220
320
420
520
620
721
822
923
1024
1124
1225
1326
1426
1526
1627
1727
1827
1927
2027
2127
2227
2327
2427
2528
2628
2728
2828
2929
3029
3129

Humidity in October

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, October lands in the dry band about 75% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1591416101
261141591
363131590
464131580
565131480
666131470
767121470
869121360
970121350
1071121250
1172121240
1273121140
1374121130
1475121030
1576121020
167811920
177911910
187911910
198011810
208011810
218011810
228111710
238210710
248210710
258210710
268310610
278310610
288310610
298310610
308410510
318410510

Wind in October

Winds average 7 mph in October.

Across October, 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.

0246810151015202531
Wind speed (mph)Feels
17calm
27calm
37calm
47calm
57calm
67calm
77calm
87calm
97calm
107calm
117calm
127calm
137calm
147calm
157calm
167calm
177calm
187calm
197calm
207calm
217calm
227calm
237calm
247calm
257light breeze
267light breeze
278light breeze
288light breeze
298light breeze
308light breeze
318light breeze

Sunrise & sunset in October

DaylightNight

Daylight runs from about 11 h 36 min at the start of October to 10 h 24 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 72 minutes over October. Sunrise moves from 5:56 AM to 6:26 AM, and sunset from 5:33 PM to 4:53 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
111.65:565:33
211.65:575:32
311.55:585:30
411.55:595:29
511.56:005:27
611.46:015:25
711.46:025:24
811.36:035:22
911.36:045:21
1011.26:055:20
1111.26:065:18
1211.26:075:17
1311.16:085:15
1411.16:095:14
1511.06:105:12
1611.06:115:11
1711.06:125:10
1810.96:135:08
1910.96:145:07
2010.96:155:06
2110.86:165:04
2210.86:175:03
2310.76:185:02
2410.76:195:01
2510.76:204:59
2610.66:214:58
2710.66:224:57
2810.66:234:56
2910.56:244:55
3010.56:254:54
3110.46:264:53

Solar energy in October

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in October, about 3.59 kWh/m².

For context, solar energy here swings from a low near 1.93 kWh/m² to a high of 6.45 kWh/m² in June across the year — October's 3.59 kWh/m² falls in the middle.

012345151015202531
Solar energy (kWh/m²)Level
14.3Bright
24.3Bright
34.2Bright
44.2Bright
54.1Bright
64.1Bright
74.0Bright
84.0Moderate
93.9Moderate
103.9Moderate
113.8Moderate
123.8Moderate
133.7Moderate
143.7Moderate
153.6Moderate
163.6Moderate
173.5Moderate
183.5Moderate
193.4Moderate
203.4Moderate
213.3Moderate
223.3Moderate
233.2Moderate
243.2Moderate
253.1Moderate
263.1Moderate
273.1Moderate
283.0Moderate
293.0Moderate
302.9Moderate
312.9Moderate
Planning a trip in October

Is October a good time to visit Marion?

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

6.9
Sightseeing
1st-best month of the year
3.9
Beach & pool
6th-best month of the year

October is a reasonable time to visit Marion for sightseeing.

What to pack for Marion in October

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

In October, Marion sees daytime highs around 69°F and nights near 50°F. Little to plan around — just the basics. About 8 days see rain.

UV index in Marion in October

LowModerateHighVery highExtreme

Clear-sky midday UV in October peaks around 4 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Marion peaks around June 23 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 at about 2 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 10 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highHighModerateJun 23UV 9Dec 22UV 2
UV index (midday)Level
Jan2Moderate
Feb4Moderate
Mar5High
Apr7High
May8Very high
Jun9Very high
Jul9Very high
Aug8Very high
Sep7High
Oct4Moderate
Nov3Moderate
Dec2Moderate

Air quality in Marion in October

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Marion is worst in July — around 19 µg/m³ PM2.5 (moderate), about 2.4× the cleanest month (November, 8 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1318 µg/m³Nov 128 µg/m³
PM2.5 (µg/m³)Level
Jan8Good
Feb11Good
Mar12Moderate
Apr11Good
May14Moderate
Jun17Moderate
Jul19Moderate
Aug14Moderate
Sep12Good
Oct8Good
Nov8Good
Dec8Good
Location & terrain

Where is Marion?

Marion sits at 37.7°N, 88.9°W, 423 ft above sea level, in United States. The nearest listed city is Carbondale, 16 mi away.

Topography around Marion

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

Within 2 miles, the terrain around Marion has only modest variations in elevation — a maximum elevation change of 148 ft around an average of 446 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 331 ft; within 50 miles, significant variations in elevation — a maximum elevation change of 1,030 ft.

The land around Marion is covered by trees (32%), grassland (26%) and artificial surfaces (24%) within 2 miles, trees (51%), grassland (21%) and cropland (20%) within 10 miles, and trees (46%) and cropland (40%) within 50 miles.

2 miles
148 ft
10 miles
331 ft
50 miles
1,030 ft
treesgrasslandcroplandartificial surfacesbare terrainwater
October weather nearby: Carbondale 16 mi · Mount Vernon 40 mi · Cape Girardeau 43 mi · Paducah 48 mi · Sikeston 69 mi · Henderson 74 mi · Evansville 77 mi · Belleville 79 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 Marion (37.7306°, -88.9331°, elevation 423 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).