Climate averages 1991–2020
Osan weather
in October.
A mild, moderately wet month: the 6th warmest and the 6th driest of the year. Meets the pleasant-weather rule
Long-term climate patterns, not a forecast for a particular trip.
October is a mild month in Osan: daytime highs average 18.9°C and nights cool to about 9.7°C. By daytime temperature it is the 6th warmest of the 12 months.
Expect about 55 mm of rain on roughly 5 days, which makes October a moderately wet month (the 6th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 11 h 16 min on an average October day.
The nearest other city in this atlas is Suwon (16 km away). In October its highs average 18.6°C, about as warm as Osan, with 55 mm of rain.
Among the 79 cities listed in South Korea, Osan ranks joint 48th of 79 for the warmest October highs and joint 14th of 79 for the driest October (rainfall, lowest first). The mean October high of those 79 cities is 19.3°C; Osan is 0.4°C cooler than that mean.
From October to November, average highs fall by 7.6°C to 11.3°C, and monthly rainfall falls from 55 mm to 47 mm.
The annual picture
October 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 | 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, selected | 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
October in nearby cities
- Suwon in OctoberSouth Korea · 16 kmHigh 18.6°C · Low 9.5°C · 55 mm rain
- Pyeongtaek in OctoberSouth Korea · 18 kmHigh 19.0°C · Low 10.1°C · 55 mm rain
- Hwaseong-si in OctoberSouth Korea · 23 kmHigh 18.1°C · Low 12.0°C · 62 mm rain
- Ansan-si in OctoberSouth Korea · 29 kmHigh 18.5°C · Low 10.9°C · 62 mm rain
- Anyang-si in OctoberSouth Korea · 30 kmHigh 18.4°C · Low 10.3°C · 55 mm rain
- Seongnam-si in OctoberSouth Korea · 32 kmHigh 18.5°C · Low 9.2°C · 58 mm rain
- Gwangju, South Korea in OctoberSouth Korea · 33 kmHigh 18.9°C · Low 9.3°C · 58 mm rain
- Icheon-si in OctoberSouth Korea · 36 kmHigh 18.8°C · Low 8.8°C · 58 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.