Climate normals · 1970–2000
Osan Climate
Osan is a city in South Korea (13) with a population of about 238,788. Its average annual temperature is 11.7°C (53°F), with roughly 1295 mm of rain per year.
11.7°C
Avg Temp
1295
Precip (mm/yr)
Aug
Hottest Month
Jan
Coldest Month
Osan Climate
Osan has an average annual temperature of 11.7°C (53°F) and receives about 1295 mm of precipitation per year. The warmest month is August and the coldest is January. Figures are 1970–2000 climate normals.
11.7°C
Avg Temp
1295
Precip (mm/yr)
Aug
Hottest Month
Jan
Coldest Month
| Month | Avg (°C/°F) | Precip |
|---|---|---|
| January | -3° / 26° | 26 mm |
| February | -1° / 31° | 30 mm |
| March | 5° / 40° | 49 mm |
| April | 12° / 53° | 89 mm |
| May | 17° / 63° | 93 mm |
| June | 22° / 71° | 131 mm |
| July | 25° / 77° | 323 mm |
| August | 25° / 78° | 273 mm |
| September | 20° / 68° | 150 mm |
| October | 13° / 56° | 53 mm |
| November | 6° / 43° | 52 mm |
| December | 0° / 31° | 26 mm |
1970–2000 normals from WorldClim 2.1 (~9 km grid). Precipitation can be less precise near mountains or coastlines, where rainfall varies sharply over short distances.
Best time to visit Osan
The most comfortable months to visit Osan are typically June, September and May, when temperatures are mildest and rainfall is relatively low. The hottest month is August (around 29°C high). The coldest is January (near -8°C low). July is usually the wettest month.
Where to stay near Osan
Planning a trip to Osan? Compare hotels and short-term rentals — live availability and prices.
Top-rated places to stay near Osan
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Planning a trip to Osan?
Get climate tips and the best lodging deals for Osan by email. No spam, unsubscribe anytime.
Other cities in South Korea
Frequently Asked Questions
The most comfortable months to visit Osan are typically June, September and May, when temperatures are mildest and rainfall is relatively low (1970–2000 climate normals).
Osan, South Korea has an average annual temperature of 11.7°C and about 1295 mm of precipitation per year. The warmest month is August and the coldest is January.
In August, the hottest month, daily highs in Osan average about 29°C (85°F).
Monthly climate normals (1970–2000) sampled from WorldClim 2.1 at ~9 km resolution. Humidity derived from vapor pressure. City coordinates and population from GeoNames.