Charleston weather in July

In July, Charleston sees average daytime highs of 85°F and overnight lows near 68°F, with 3.7 in of rain across 10.7 wet days and about 14.5 hours of daylight. It is the 1st-warmest and 4th-wettest month of the year here.

Day-to-day highs hold fairly steady near 85°F through the month. The sky is clear or mostly clear about 39% of the time in July, and the air most often feels muggy.

Daylight stretches from about 14 h 48 min at the start of July to 14 h 06 min by month's end. Set against the rest of the year, July is Charleston's 3rd-clearest and 11th-windiest month. For the whole year in context, see Charleston's year-round climate.

Daytime high
85°
1st warmest
Overnight low
68°
12th coldest
Rainfall
3.7 in
10.7 wet days
Daylight
14 h 30 min
4:42 AM – 7:14 PM
Cloud cover
53%
3rd clearest
Wind
6 mph
11th windiest
Solar energy
6.41 kWh/m²
Travel score
5.4
out of 10

Charleston is city in and the county seat of Coles County, Illinois, United States.

Density
876/km²
people per km²
Founded
1831

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

Temperature in July

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 85°F through the month.

A typical July day in Charleston reaches about 85°F in the afternoon and slips back to 68°F overnight — a 17°F spread between the day's warmth and the night's chill. On most days the high lands between 77°F and 92°F. Set against its neighbours, July runs about 3°F warmer than June and on par with August.

50°60°70°80°90°151015202531
Avg high (°F)Avg low (°F)
18467
28467
38467
48467
58468
68568
78568
88568
98568
108568
118568
128568
138568
148568
158568
168568
178568
188568
198568
208568
218568
228568
238568
248568
258468
268467
278467
288467
298467
308467
318467

How July really feels in Charleston

Once humidity and wind are folded in, July 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

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

Charleston weather by month

How July compares with the rest of the year at a glance. July is the 1st-warmest and 4th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan37° / 22°3.08.93.89.50.0
Feb41° / 25°2.57.83.410.40.3
Mar52° / 34°3.410.51.611.72.7
Apr64° / 45°4.811.80.3135.4
May74° / 56°4.712.7014.16.3
Jun82° / 65°4.211.2014.75.9
Jul85° / 68°3.710.7014.55.4
Aug83° / 65°3.08.5013.66.0
Sep78° / 58°2.97.2012.37.3
Oct65° / 46°3.38.20.1116.2
Nov52° / 36°3.58.30.79.82.8
Dec41° / 27°2.78.92.99.30.2

Cloud cover in July

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 39% of the time in July.

Beyond those clear spells, partly cloudy skies cover about 17% of July, with mostly cloudy or overcast conditions the remaining 44%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
15644
25644
35743
45743
55743
65842
75842
85842
95941
105842
115842
125743
135743
145644
155545
165545
175545
185446
195446
205347
215446
225446
235446
245446
255545
265644
275743
285743
295842
305842
315941

Chance of precipitation in July

Any precipitation

Charleston gets around 3.7 in of rain over 10.7 wet days in July. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 34% and peaks near 36% on the wettest days.

0%10%20%30%40%50%151015202531
Rain chance (%)
136
236
336
436
536
636
736
836
936
1035
1135
1235
1335
1435
1535
1635
1734
1834
1934
2034
2134
2234
2333
2433
2533
2633
2732
2832
2932
3031
3131

Humidity in July

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, July lands in the muggy band about 29% of days. Sticky, muggy-or-worse air turns up on roughly 58% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
18162333190
28162333200
38162333200
47162333210
57162333211
67162332221
76162332221
86162332231
96152332231
105152232241
115152232251
125142232262
134142131272
144142131282
154142130292
164142030302
174142029302
184142028312
194142028322
205142027322
215142026332
225142026332
235142125332
245142125332
255152224322
265152224322
275162324312
285162324302
295162424291
306162425281
316172425271

Wind in July

Winds average 6 mph in July.

Across July, daily wind ranges from about 6 mph on the calmest days to 7 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (mph)Feels
17calm
27calm
37calm
47calm
57calm
67calm
77calm
86calm
96calm
106calm
116calm
126calm
136calm
146calm
156calm
166calm
176calm
186calm
196calm
206calm
216calm
226calm
236calm
246calm
256calm
266calm
276calm
286calm
296calm
306calm
316calm

Sunrise & sunset in July

DaylightNight

Daylight runs from about 14 h 48 min at the start of July to 14 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 42 minutes over July. Sunrise moves from 4:33 AM to 4:55 AM, and sunset from 7:19 PM to 7:03 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
114.84:337:19
214.74:347:19
314.74:347:19
414.74:357:18
514.74:357:18
614.74:367:18
714.74:367:18
814.74:377:18
914.74:387:17
1014.64:387:17
1114.64:397:17
1214.64:407:16
1314.64:407:16
1414.64:417:15
1514.64:427:15
1614.54:427:14
1714.54:437:14
1814.54:447:13
1914.54:457:13
2014.44:457:12
2114.44:467:11
2214.44:477:10
2314.44:487:10
2414.34:497:09
2514.34:507:08
2614.34:507:07
2714.34:517:06
2814.24:527:06
2914.24:537:05
3014.24:547:04
3114.14:557:03

Solar energy in July

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in July, about 6.41 kWh/m².

For context, solar energy here swings from a low near 1.79 kWh/m² to a high of 6.44 kWh/m² in June across the year — July's 6.41 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
16.5Intense
26.5Intense
36.5Intense
46.5Intense
56.5Intense
66.5Intense
76.5Intense
86.5Intense
96.5Intense
106.5Intense
116.5Intense
126.5Intense
136.5Intense
146.5Intense
156.5Intense
166.5Intense
176.4Intense
186.4Intense
196.4Intense
206.4Intense
216.4Intense
226.3Intense
236.3Intense
246.3Intense
256.3Intense
266.3Intense
276.3Intense
286.2Intense
296.2Intense
306.2Intense
316.2Intense
Planning a trip in July

Is July a good time to visit Charleston?

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

5.4
Sightseeing
6th-best month of the year
7.0
Beach & pool
2nd-best month of the year

July is a reasonable time to visit Charleston for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Charleston in July

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

In July, Charleston sees daytime highs around 85°F and nights near 68°F. Pack light clothes and sun protection. Worth having: rain gear. About 11 days see rain.

light clothessun protectionrain gear

UV index in Charleston in July

LowModerateHighVery highExtreme

Clear-sky midday UV in July peaks around 9 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Charleston peaks around July 10 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 23 at about 2 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 9 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highHighModerateJul 10UV 9Dec 23UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar5Moderate
Apr6High
May8Very high
Jun9Very high
Jul9Very high
Aug8Very high
Sep6High
Oct4Moderate
Nov3Moderate
Dec2Low

Air quality in Charleston in July

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Charleston is worst in July — around 16 µg/m³ PM2.5 (moderate), about 2.1× the cleanest month (October, 8 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateModerateGoodJul 1616 µg/m³Oct 218 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb13Moderate
Mar13Moderate
Apr11Good
May14Moderate
Jun15Moderate
Jul16Moderate
Aug14Moderate
Sep11Good
Oct8Good
Nov8Good
Dec9Good
Location & terrain

Where is Charleston?

Charleston sits at 39.5°N, 88.2°W, 669 ft above sea level, in United States. The nearest listed city is Mattoon, 11 mi away.

Topography around Charleston

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

Within 2 miles, the terrain around Charleston has only modest variations in elevation — a maximum elevation change of 187 ft around an average of 676 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 282 ft; within 50 miles, only modest variations in elevation — a maximum elevation change of 456 ft.

The land around Charleston is covered by cropland (38%) and trees (32%) within 2 miles, cropland (68%) and trees (23%) within 10 miles, and cropland (74%) and trees (21%) within 50 miles.

2 miles
187 ft
10 miles
282 ft
50 miles
456 ft
treesgrasslandcroplandartificial surfacesbare terrainwater
July weather nearby: Mattoon 11 mi · Terre Haute 41 mi · Urbana 42 mi · Champaign 43 mi · Decatur 48 mi · Danville 52 mi · Vincennes 66 mi · Crawfordsville 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 Charleston (39.4962°, -88.1762°, elevation 669 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).