Climate averages 1991–2020
Osan weather
in July.
A hot, very wet month: the 2nd warmest and the wettest of the year.
Long-term climate patterns, not a forecast for a particular trip.
July is a hot month in Osan: daytime highs average 28.2°C and nights cool to about 21.6°C. By daytime temperature it is the 2nd warmest of the 12 months.
Expect about 279 mm of rain on roughly 15 days, which makes July a very wet month (the wettest month of the year). Daylight, from sunrise to sunset, lasts about 14 h 27 min on an average July day.
The nearest other city in this atlas is Suwon (16 km away). In July its highs average 27.7°C, about as warm as Osan, with 279 mm of rain.
Among the 79 cities listed in South Korea, Osan ranks joint 32nd of 79 for the warmest July highs and joint 50th of 79 for the driest July (rainfall, lowest first). The mean July high of those 79 cities is 27.8°C; Osan is 0.4°C warmer than that mean.
From July to August, average highs rise by 0.6°C to 28.8°C, and monthly rainfall falls from 279 mm to 231 mm.
The annual picture
July in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Osan climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 2.2°C-5.5°C | -5.5°C | 20 | 3.8 | 9.910 h |
| February | 4.9°C-3.8°C | -3.8°C | 27 | 4.1 | 10.811 h |
| March | 10.2°C0.1°C | 0.1°C | 39 | 6.1 | 11.912 h |
| April | 16.8°C5.7°C | 5.7°C | 69 | 7.1 | 13.113 h |
| May | 22.2°C11.6°C | 11.6°C | 88 | 7.1 | 14.114 h |
| June | 26.5°C17.1°C | 17.1°C | 118 | 7.6 | 14.715 h |
| July, selected | 28.2°C21.6°C | 21.6°C | 279 | 15.3 | 14.414 h |
| August | 28.8°C22.3°C | 22.3°C | 231 | 14.0 | 13.614 h |
| September | 24.8°C16.9°C | 16.9°C | 124 | 7.8 | 12.512 h |
| October | 18.9°C9.7°C | 9.7°C | 55 | 5.2 | 11.311 h |
| November | 11.3°C2.6°C | 2.6°C | 47 | 7.3 | 10.210 h |
| December | 4.2°C-3.6°C | -3.6°C | 23 | 5.1 | 9.710 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
July in nearby cities
- Suwon in JulySouth Korea · 16 kmHigh 27.7°C · Low 21.3°C · 279 mm rain
- Pyeongtaek in JulySouth Korea · 18 kmHigh 28.5°C · Low 21.7°C · 260 mm rain
- Hwaseong-si in JulySouth Korea · 23 kmHigh 26.2°C · Low 21.6°C · 298 mm rain
- Ansan-si in JulySouth Korea · 29 kmHigh 27.1°C · Low 21.6°C · 298 mm rain
- Anyang-si in JulySouth Korea · 30 kmHigh 27.2°C · Low 21.4°C · 314 mm rain
- Seongnam-si in JulySouth Korea · 32 kmHigh 27.8°C · Low 21.3°C · 340 mm rain
- Gwangju, South Korea in JulySouth Korea · 33 kmHigh 28.5°C · Low 21.6°C · 340 mm rain
- Icheon-si in JulySouth Korea · 36 kmHigh 28.4°C · Low 21.3°C · 307 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Osan) is explained once on the Osan year overview and on the Sources, method and limits page.
Suwon lies in the same rainfall cell, so its rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.