Cheonan weather in August

In August, Cheonan sees average daytime highs of 30°C and overnight lows near 22°C, with 237 mm of rain across 15.4 wet days and about 13.4 hours of daylight. It is the 1st-warmest and 2nd-wettest month of the year here.

Highs ease over the month, from about 31°C in the first days to 28°C by the end. The sky is clear or mostly clear about 24% of the time in August, and the air most often feels oppressive.

Daylight stretches from about 13 h 54 min at the start of August to 12 h 54 min by month's end. Set against the rest of the year, August is Cheonan's 11th-clearest and 9th-windiest month. For the whole year in context, see Cheonan's year-round climate.

Daytime high
30°
1st warmest
Overnight low
22°
12th coldest
Rainfall
237 mm
15.4 wet days
Daylight
13 h 24 min
5:53 AM – 7:18 PM
Cloud cover
66%
11th clearest
Wind
8 km/h
9th windiest
Solar energy
4.37 kWh/m²
Travel score
4.5
out of 10

Cheonan is big city of South Korea.

Density
1,035/km²
people per km²

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

Temperature in August

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 31°C in the first days to 28°C by the end.

A typical August day in Cheonan reaches about 30°C in the afternoon and slips back to 22°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between 26°C and 33°C. Set against its neighbours, August runs on par with July and about 4°C warmer than September.

15°20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
13123
23124
33124
43124
53123
63123
73123
83123
93123
103023
113023
123023
133023
143023
153023
163023
173022
183022
193022
202922
212922
222922
232922
242921
252921
262921
272821
282821
292820
302820
312820

How August really feels in Cheonan

Once humidity and wind are folded in, August averages 19 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
19
heat index over the day's high
Days feeling ≤ C
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.

Cheonan weather by month

How August compares with the rest of the year at a glance. August is the 1st-warmest and 2nd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / -5°224.22.29.80.0
Feb / -4°304.31.610.60.5
Mar12° / 476.51.211.73.4
Apr19° / 777.2012.96.4
May24° / 13°897.5013.97.3
Jun28° / 18°1258.6014.56.2
Jul29° / 22°26516.2014.34.5
Aug30° / 22°23715.4013.44.5
Sep26° / 17°1398.6012.26.9
Oct20° / 10°584.80117.3
Nov12° / 456.50.2103.8
Dec / -3°2451.69.50.3

Cloud cover in August

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 24% of the time in August.

Beyond those clear spells, partly cloudy skies cover about 16% of August, with mostly cloudy or overcast conditions the remaining 60%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
13862
23862
33961
43961
54060
64060
74060
84159
94159
104159
114060
124060
133961
143961
153961
163961
173961
183862
193961
203961
213961
223961
233961
243961
254060
264060
274159
284159
294258
304258
314258

Chance of precipitation in August

Any precipitation

Cheonan gets around 237 mm of rain over 15.4 wet days in August. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 49% and peaks near 51% on the wettest days. The odds ease toward the end of the month.

0%20%40%60%151015202531
Rain chance (%)
150
251
351
451
551
651
751
851
951
1051
1151
1250
1350
1450
1550
1649
1749
1849
1949
2048
2148
2248
2348
2447
2547
2647
2746
2845
2945
3044
3143

Humidity in August

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, August lands in the oppressive band about 47% of days. Sticky, muggy-or-worse air turns up on roughly 89% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
1003156022
2003156022
3003155923
4003155923
5003155923
6004165723
7004175722
8004185721
9004195621
10004215520
11004225618
12005245417
13005265316
14015275215
15015295114
16016315013
17016334912
18017344711
19017364610
2002837449
2102938438
22021039427
23031239406
24031339386
25041539365
26051639355
27051839334
28162039314
29172238303
30182437283
31192636262

Wind in August

Winds average 8 km/h in August.

Across August, daily wind ranges from about 8 km/h on the calmest days to 9 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
19calm
29calm
39calm
49calm
58calm
68calm
78calm
88calm
98calm
108calm
118calm
128calm
138calm
148calm
158calm
168calm
178calm
188calm
198calm
208calm
218calm
228calm
238calm
248calm
258calm
268calm
278calm
288calm
298calm
308calm
318calm

Sunrise & sunset in August

DaylightNight

Daylight runs from about 13 h 54 min 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 60 minutes over August. Sunrise moves from 5:40 AM to 6:06 AM, and sunset from 7:35 PM to 6:57 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.95:407:35
213.95:417:34
313.85:427:33
413.85:437:32
513.85:447:31
613.85:457:30
713.75:457:29
813.75:467:27
913.75:477:26
1013.65:487:25
1113.65:497:24
1213.65:507:23
1313.55:507:22
1413.55:517:21
1513.55:527:19
1613.45:537:18
1713.45:547:17
1813.35:557:15
1913.35:557:14
2013.35:567:13
2113.25:577:12
2213.25:587:10
2313.25:597:09
2413.16:007:07
2513.16:017:06
2613.16:017:05
2713.06:027:03
2813.06:037:02
2912.96:047:00
3012.96:056:59
3112.96:066:57

Solar energy in August

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in August, about 4.37 kWh/m².

For context, solar energy here swings from a low near 2.31 kWh/m² to a high of 5.88 kWh/m² in May across the year — August's 4.37 kWh/m² falls in the middle.

024151015202531
Solar energy (kWh/m²)Level
14.6Bright
24.6Bright
34.6Bright
44.6Bright
54.6Bright
64.6Bright
74.6Bright
84.5Bright
94.5Bright
104.5Bright
114.5Bright
124.5Bright
134.4Bright
144.4Bright
154.4Bright
164.4Bright
174.3Bright
184.3Bright
194.3Bright
204.3Bright
214.3Bright
224.3Bright
234.2Bright
244.2Bright
254.2Bright
264.2Bright
274.2Bright
284.2Bright
294.2Bright
304.2Bright
314.2Bright
Planning a trip in August

Hazard calendar for Cheonan

In seasonPeak

In August, Cheonan sits inside its pacific typhoon and rainy season season. The full year is below, with each hazard's peak months called out.

Cheonan sits in the Pacific typhoon belt; the season peaks July–October.

Cheonan's rainy season runs June–September, when most of the year's rain falls.

Pacific typhoon
Rainy season
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is August a good time to visit Cheonan?

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

4.5
Sightseeing
6th-best month of the year
6.0
Beach & pool
4th-best month of the year

August is a reasonable time to visit Cheonan for sightseeing.

What to pack for Cheonan in August

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

In August, Cheonan sees daytime highs around 30°C and nights near 22°C. Pack light clothes and rain gear. About 15 days see rain.

light clothesrain gear

Sea temperature near Cheonan in August

The nearest coast averages about 23°C in August — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 59 km away) is warmest in August at about 23°C and coldest in February near 4°C.

It's comfortable for a long swim from Jul 12 to Oct 14 — about 3.1 months when the water holds above 20°C.

0°10°20°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan6Bracing
Feb4Bracing
Mar5Bracing
Apr8Bracing
May12Bracing
Jun16Cool
Jul21Refreshing
Aug23Refreshing
Sep23Refreshing
Oct20Cool
Nov15Cool
Dec10Bracing

UV index in Cheonan in August

LowModerateHighVery highExtreme

Clear-sky midday UV in August peaks around 8 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Cheonan peaks around August 13 at about 8 (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 10 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highHighModerateAug 13UV 8Dec 23UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar5Moderate
Apr6High
May6High
Jun7High
Jul8Very high
Aug8Very high
Sep7Very high
Oct5High
Nov3Moderate
Dec2Low

Air quality in Cheonan 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 Cheonan is worst in March — around 80 µg/m³ PM2.5 (unhealthy), about 1.8× the cleanest month (July, 45 µg/m³).

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

0306090JanFebMarAprMayJunJulAugSepOctNovDecUnhealthyPoorUnhealthyMar 1479 µg/m³Jul 2345 µg/m³
PM2.5 (µg/m³)Level
Jan69Unhealthy
Feb72Unhealthy
Mar80Unhealthy
Apr65Unhealthy
May58Unhealthy
Jun54Poor
Jul45Poor
Aug45Poor
Sep56Unhealthy
Oct67Unhealthy
Nov72Unhealthy
Dec65Unhealthy
Location & terrain

Where is Cheonan?

Cheonan sits at 36.8°N, 127.2°E, 40 m above sea level, in South Korea. The nearest listed city is Seonghwan, 12 km away.

Cheongju-si

Topography around Cheonan

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Cheonan.

Within 3 km, the terrain around Cheonan has significant variations in elevation — a maximum elevation change of 287 m around an average of 67 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 602 m; within 80 km, large variations in elevation — a maximum elevation change of 1,032 m.

The land around Cheonan is covered by artificial surfaces (64%) and trees (26%) within 3 km, trees (51%), cropland (23%) and artificial surfaces (20%) within 16 km, and trees (55%) and cropland (22%) within 80 km.

3 km
287 m
16 km
602 m
80 km
1,032 m
treesgrasslandcroplandartificial surfacesbare terrainwater
August weather nearby: Seonghwan 12 km · Asan 13 km · Pyeongtaek 22 km · Anseong 25 km · Chinch'ŏn 27 km · Sejong 27 km · Yesan 31 km · Cheongju-si 35 km

South Korea travel facts

Travel advisory
Level 1
Exercise Normal Precautions
Power plugs
Type C / F
220 V · 60 Hz
Prices
≈ 57% of US
price level, 2025
GDP per capita
$36,227
2025
Happiness
6.0 / 10
World Happiness, 2025
Safe drinking water
99%
of population, 2024
Homicide rate
0.5
per 100k, 2023
Road deaths
8.6
per 100k/yr, 2019
Income group
High
World Bank
English
Moderate
EF EPI 522
Religion
none 60%Protestant 17%Buddhist 16%Catholic 6%

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 Cheonan (36.8065°, 127.1522°, elevation 40 m), 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). Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. 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).