Carbondale weather in August

In August, Carbondale sees average daytime highs of 87°F and overnight lows near 69°F, with 2.7 in of rain across 7.6 wet days and about 13.5 hours of daylight. It is the 2nd-warmest and 12th-wettest month of the year here.

Day-to-day highs hold fairly steady near 87°F through the month. The sky is clear or mostly clear about 42% of the time in August, and the air most often feels muggy.

Daylight stretches from about 14 hours at the start of August to 12 h 54 min by month's end. Set against the rest of the year, August is Carbondale's 3rd-clearest and 12th-windiest month. For the whole year in context, see Carbondale's year-round climate.

Daytime high
87°
2nd warmest
Overnight low
69°
11th coldest
Rainfall
2.7 in
7.6 wet days
Daylight
13 h 30 min
5:17 AM – 6:45 PM
Cloud cover
50%
3rd clearest
Wind
5 mph
12th windiest
Solar energy
5.81 kWh/m²
Travel score
5.1
out of 10

Carbondale is city in Jackson County, Illinois, United States.

Density
582/km²
people per km²
Founded
1852

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

Temperature in August

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 87°F through the month.

A typical August day in Carbondale reaches about 87°F in the afternoon and slips back to 69°F overnight — a 18°F spread between the day's warmth and the night's chill. On most days the high lands between 80°F and 94°F. Set against its neighbours, August runs on par with July and about 6°F warmer than September.

60°70°80°90°151015202531
Avg high (°F)Avg low (°F)
18871
28771
38770
48770
58770
68770
78770
88770
98770
108770
118769
128769
138769
148769
158769
168769
178769
188769
198769
208769
218769
228769
238769
248769
258768
268668
278668
288668
298668
308667
318567

How August really feels in Carbondale

Once humidity and wind are folded in, August averages 7 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
7
heat index over the day's high
Days feeling ≤ 32°F
0
wind chill below the day's low

The story in August is heat — humidity pushes the afternoon "feels like" well above the raw temperature.

Carbondale weather by month

How August compares with the rest of the year at a glance. August is the 2nd-warmest and 12th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan42° / 27°3.38.92.39.70.3
Feb47° / 30°3.082.210.51.4
Mar57° / 39°4.311.20.911.73.9
Apr68° / 49°5.011.6012.96.0
May76° / 59°4.612.50146.3
Jun85° / 68°3.610.5014.65.3
Jul88° / 71°3.510014.34.5
Aug87° / 69°2.77.6013.55.1
Sep81° / 61°3.07.4012.36.9
Oct69° / 50°3.67.70.1116.9
Nov56° / 39°3.78.60.5103.9
Dec46° / 31°3.391.99.41.1

Cloud cover in August

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 42% of the time in August.

Beyond those clear spells, partly cloudy skies cover about 18% of August, with mostly cloudy or overcast conditions the remaining 39%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
16139
26040
36040
46040
56139
66139
76139
86040
96040
106040
116040
125941
135941
145941
155941
165941
175941
186040
196040
206040
216040
226040
236139
246139
256139
266238
276238
286337
296337
306436
316337

Chance of precipitation in August

Any precipitation

Carbondale gets around 2.7 in of rain over 7.6 wet days in August, the driest month. 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 30% on the wettest days. The odds ease toward the end of the month.

0%10%20%30%40%151015202531
Rain chance (%)
130
230
329
429
528
628
728
827
927
1027
1126
1226
1326
1425
1524
1624
1723
1823
1922
2022
2122
2222
2322
2422
2522
2623
2723
2823
2923
3023
3123

Humidity in August

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, August lands in the muggy band about 30% of days. Sticky, muggy-or-worse air turns up on roughly 62% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
12122028362
22112029352
33112030342
43112130342
53112130332
63112130332
74112131322
84122031322
94122030322
105122030312
115131930312
125131930312
135141930312
145141930302
155151930302
165151930301
175152030291
185152030291
195152030291
205152030291
216142030291
226142030291
236142030291
246132031300
256132131290
267132131290
277132131280
288132131270
298132131260
309142131250
3110142131240

Wind in August

Winds average 5 mph in August, the calmest month.

Across August, daily wind ranges from about 5 mph on the calmest days to 5 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (mph)Feels
15calm
25calm
35calm
45calm
55calm
65calm
75calm
85calm
95calm
105calm
115calm
125calm
135calm
145calm
155calm
165calm
175calm
185calm
195calm
205calm
215calm
225calm
235calm
245calm
255calm
265calm
275calm
285calm
295calm
305calm
315calm

Sunrise & sunset in August

DaylightNight

Daylight runs from about 14 hours at the start of August to 12 h 54 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 66 minutes over August. Sunrise moves from 5:04 AM to 5:30 AM, and sunset from 7:02 PM to 6:24 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
114.05:047:02
213.95:057:01
313.95:067:00
413.95:066:59
513.85:076:58
613.85:086:57
713.85:096:56
813.75:106:55
913.75:116:54
1013.75:126:52
1113.65:136:51
1213.65:136:50
1313.65:146:49
1413.55:156:48
1513.55:166:46
1613.55:176:45
1713.45:186:44
1813.45:196:42
1913.45:206:41
2013.35:206:40
2113.35:216:38
2213.25:226:37
2313.25:236:35
2413.25:246:34
2513.15:256:33
2613.15:266:31
2713.15:276:30
2813.05:276:28
2913.05:286:27
3012.95:296:25
3112.95:306:24

Solar energy in August

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in August, about 5.81 kWh/m².

For context, solar energy here swings from a low near 1.94 kWh/m² to a high of 6.46 kWh/m² in June across the year — August's 5.81 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
16.2Intense
26.1Intense
36.1Intense
46.1Intense
56.1Intense
66.0Intense
76.0Intense
86.0Bright
96.0Bright
105.9Bright
115.9Bright
125.9Bright
135.8Bright
145.8Bright
155.8Bright
165.8Bright
175.8Bright
185.7Bright
195.7Bright
205.7Bright
215.7Bright
225.6Bright
235.6Bright
245.6Bright
255.5Bright
265.5Bright
275.5Bright
285.5Bright
295.4Bright
305.4Bright
315.3Bright
Planning a trip in August

Is August a good time to visit Carbondale?

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

5.1
Sightseeing
6th-best month of the year
7.2
Beach & pool
1st-best month of the year

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

What to pack for Carbondale in August

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

In August, Carbondale sees daytime highs around 87°F and nights near 69°F. Pack light clothes. Worth having: sun protection. About 8 days see rain.

light clothessun protection

UV index in Carbondale in August

LowModerateHighVery highExtreme

Clear-sky midday UV in August peaks around 8 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Carbondale peaks around June 22 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 22UV 9Dec 22UV 2
UV index (midday)Level
Jan2Moderate
Feb4Moderate
Mar5High
Apr7High
May8Very high
Jun10Very high
Jul9Very high
Aug8Very high
Sep7High
Oct4Moderate
Nov3Moderate
Dec2Moderate

Air quality in Carbondale in August

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Carbondale 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 Carbondale?

Carbondale sits at 37.7°N, 89.2°W, 413 ft above sea level, in United States. The nearest listed city is Marion, 16 mi away.

Topography around Carbondale

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

Within 2 miles, the terrain around Carbondale has only modest variations in elevation — a maximum elevation change of 167 ft around an average of 420 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 489 ft; within 50 miles, significant variations in elevation — a maximum elevation change of 1,030 ft.

The land around Carbondale is covered by trees (48%) and artificial surfaces (22%) within 2 miles, trees (61%) within 10 miles, and trees (46%) and cropland (39%) within 50 miles.

2 miles
167 ft
10 miles
489 ft
50 miles
1,030 ft
treesgrasslandcroplandartificial surfacesbare terrainwater
August weather nearby: Marion 16 mi · Cape Girardeau 34 mi · Mount Vernon 44 mi · Paducah 56 mi · Sikeston 62 mi · Farmington 66 mi · Belleville 69 mi · O'Fallon 71 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 Carbondale (37.7273°, -89.2168°, elevation 413 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).