Decatur weather in June

In June, Decatur sees average daytime highs of 82°F and overnight lows near 64°F, with 4.3 in of rain across 10.9 wet days and about 14.8 hours of daylight. It is the 3rd-warmest and 3rd-wettest month of the year here.

Highs climb over the month, from about 79°F in the first days to 84°F by the end. The sky is clear or mostly clear about 33% of the time in June, and the air most often feels muggy.

Daylight stretches from about 14 h 36 min at the start of June to 14 h 48 min by month's end. Set against the rest of the year, June is Decatur's 5th-clearest and 10th-windiest month. For the whole year in context, see Decatur's year-round climate.

Daytime high
82°
3rd warmest
Overnight low
64°
10th coldest
Rainfall
4.3 in
10.9 wet days
Daylight
14 h 48 min
4:32 AM – 7:20 PM
Cloud cover
57%
5th clearest
Wind
7 mph
10th windiest
Solar energy
6.44 kWh/m²
Travel score
6.0
out of 10

Decatur is city in Macon County, Illinois, United States.

Density
602/km²
people per km²
Founded
1823

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

Temperature in June

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 79°F in the first days to 84°F by the end.

A typical June day in Decatur reaches about 82°F in the afternoon and slips back to 64°F overnight — a 17°F spread between the day's warmth and the night's chill. On most days the high lands between 73°F and 90°F. Set against its neighbours, June runs about 8°F warmer than May and about 3°F cooler than July.

50°60°70°80°90°151015202530
Avg high (°F)Avg low (°F)
17860
27861
37961
47962
57962
68062
78062
88063
98163
108163
118164
128264
138264
148265
158265
168265
178365
188365
198366
208366
218366
228366
238366
248366
258366
268367
278467
288467
298467
308467

How June really feels in Decatur

Once humidity and wind are folded in, June 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

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

Decatur weather by month

How June compares with the rest of the year at a glance. June is the 3rd-warmest and 3rd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan36° / 21°2.78.549.50.0
Feb40° / 24°2.37.53.410.40.2
Mar52° / 34°3.39.71.511.72.7
Apr64° / 44°4.611.80.3135.3
May73° / 55°4.813.2014.26.2
Jun82° / 64°4.310.9014.86.0
Jul84° / 67°3.610.3014.55.5
Aug83° / 65°3.08.5013.66.1
Sep78° / 57°3.27.4012.37.3
Oct65° / 46°3.58.60.110.96.2
Nov51° / 35°3.58.70.89.82.7
Dec40° / 26°2.58.72.99.20.2

Cloud cover in June

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 33% of the time in June.

Beyond those clear spells, partly cloudy skies cover about 19% of June, with mostly cloudy or overcast conditions the remaining 48%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
14555
24555
34654
44753
54753
64852
74852
84951
94951
105050
115149
125149
135149
145248
155248
165248
175347
185347
195446
205446
215545
225545
235644
245545
255545
265545
275644
285743
295743
305743

Chance of precipitation in June

Any precipitation

Decatur gets around 4.3 in of rain over 10.9 wet days in June. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 37% and peaks near 39% on the wettest days.

0%10%20%30%40%50%151015202530
Rain chance (%)
139
238
338
438
537
637
737
837
937
1037
1137
1238
1338
1438
1538
1638
1738
1838
1938
2038
2137
2237
2336
2436
2536
2636
2735
2835
2935
3034

Humidity in June

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, June lands in the muggy band about 30% of days. Sticky, muggy-or-worse air turns up on roughly 41% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1362021212
2352020222
3342120233
4322120243
5312120254
6302120254
7282120265
8272120275
9262021276
10242021287
11222022298
12211922299
13191823309
141818233110
151617243111
161517243212
171417243213
181316243313
191216243314
201216243314
211117243415
221017243415
231017233416
24917233416
25918223517
26818213518
27818213518
28818203419
29818203420
30817203421

Wind in June

Winds average 7 mph in June.

Across June, 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.

0246810151015202530
Wind speed (mph)Feels
18light breeze
28light breeze
38light breeze
48light breeze
58light breeze
68light breeze
78light breeze
88light breeze
98light breeze
108light breeze
118light breeze
127light breeze
137light breeze
147calm
157calm
167calm
177calm
187calm
197calm
207calm
217calm
227calm
237calm
247calm
257calm
267calm
277calm
287calm
297calm
307calm

Sunrise & sunset in June

DaylightNight

Daylight runs from about 14 h 36 min at the start of June to 14 h 48 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 12 minutes over June. Sunrise moves from 4:35 AM to 4:35 AM, and sunset from 7:12 PM to 7:23 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
114.64:357:12
214.64:357:12
314.64:347:13
414.74:347:14
514.74:347:14
614.74:337:15
714.74:337:16
814.74:337:16
914.74:337:17
1014.84:327:17
1114.84:327:18
1214.84:327:18
1314.84:327:19
1414.84:327:19
1514.84:327:20
1614.84:327:20
1714.84:327:21
1814.84:327:21
1914.84:327:21
2014.84:327:22
2114.84:327:22
2214.84:327:22
2314.84:337:22
2414.84:337:23
2514.84:337:23
2614.84:347:23
2714.84:347:23
2814.84:347:23
2914.84:357:23
3014.84:357:23

Solar energy in June

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in June, about 6.44 kWh/m² — the sunniest month for solar.

For context, solar energy here swings from a low near 1.8 kWh/m² to a high of 6.44 kWh/m² in June across the year — June's 6.44 kWh/m² sits near the top of that range.

0246151015202530
Solar energy (kWh/m²)Level
16.1Intense
26.2Intense
36.2Intense
46.2Intense
56.2Intense
66.3Intense
76.3Intense
86.3Intense
96.3Intense
106.3Intense
116.4Intense
126.4Intense
136.4Intense
146.4Intense
156.4Intense
166.5Intense
176.5Intense
186.5Intense
196.5Intense
206.5Intense
216.5Intense
226.5Intense
236.5Intense
246.5Intense
256.6Intense
266.6Intense
276.6Intense
286.6Intense
296.6Intense
306.6Intense
Planning a trip in June

Hazard calendar for Decatur

In seasonPeak

In June, Decatur sits inside its atlantic hurricane season. The full year is below, with each hazard's peak months called out.

Decatur sits in the Atlantic hurricane belt; the season peaks August–October.

Atlantic hurricane
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is June a good time to visit Decatur?

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

6.0
Sightseeing
5th-best month of the year
6.5
Beach & pool
4th-best month of the year

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

What to pack for Decatur in June

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

In June, Decatur sees daytime highs around 82°F and nights near 64°F. Pack light clothes and sun protection. Worth having: rain gear. About 11 days see rain.

light clothessun protectionrain gear

UV index in Decatur in June

LowModerateHighVery highExtreme

Clear-sky midday UV in June 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 Decatur peaks around June 22 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near January 1 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 highHighModerateJun 22UV 9Jan 1UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar5Moderate
Apr6High
May8Very high
Jun9Very high
Jul9Very high
Aug8Very high
Sep6High
Oct4Moderate
Nov3Moderate
Dec2Low

Air quality in Decatur in June

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Decatur is worst in July — around 17 µg/m³ PM2.5 (moderate), about 2.1× the cleanest month (October, 8 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodModerateGoodJul 1716 µg/m³Oct 228 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb13Moderate
Mar12Moderate
Apr11Good
May14Moderate
Jun14Moderate
Jul17Moderate
Aug15Moderate
Sep12Good
Oct8Good
Nov8Good
Dec9Good
Location & terrain

Where is Decatur?

Decatur sits at 39.8°N, 89.0°W, 673 ft above sea level, in United States. The nearest listed city is Springfield, 37 mi away.

Topography around Decatur

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

Within 2 miles, the terrain around Decatur has only modest variations in elevation — a maximum elevation change of 164 ft around an average of 666 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 197 ft; within 50 miles, only modest variations in elevation — a maximum elevation change of 489 ft.

The land around Decatur is covered by trees (43%) and artificial surfaces (34%) within 2 miles, cropland (68%) within 10 miles, and cropland (83%) within 50 miles.

2 miles
164 ft
10 miles
197 ft
50 miles
489 ft
treesgrasslandcroplandartificial surfacesbare terrainwater
June weather nearby: Springfield 37 mi · Mattoon 40 mi · Champaign 42 mi · Urbana 43 mi · Bloomington 45 mi · Normal 47 mi · Charleston 48 mi · Morton 60 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 Decatur (39.8403°, -88.9548°, elevation 673 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. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). 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).