Climate averages 1991–2020
Asan weather
in May.
A warm, moderately wet month: the 5th warmest and the 8th driest of the year. Meets the pleasant-weather rule
Long-term climate patterns, not a forecast for a particular trip.
May is a warm month in Asan: daytime highs average 23.0°C and nights cool to about 12.0°C. By daytime temperature it is the 5th warmest of the 12 months.
Expect about 80 mm of rain on roughly 7 days, which makes May a moderately wet month (the 8th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 14 h 07 min on an average May day.
The nearest other city in this atlas is Cheonan (13 km away). In May its highs average 23.5°C, about as warm as Asan, with 89 mm of rain.
Among the 79 cities listed in South Korea, Asan ranks joint 18th of 79 for the warmest May highs and 3rd of 79 for the driest May (rainfall, lowest first). The mean May high of those 79 cities is 21.9°C; Asan is 1.1°C warmer than that mean.
From May to June, average highs rise by 4.2°C to 27.2°C, and monthly rainfall rises from 80 mm to 121 mm.
The annual picture
May 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
Asan climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 2.6°C-4.8°C | -4.8°C | 21 | 4.1 | 9.910 h |
| February | 5.2°C-3.5°C | -3.5°C | 28 | 4.2 | 10.811 h |
| March | 10.7°C0.3°C | 0.3°C | 43 | 6.1 | 11.912 h |
| April | 17.4°C6.1°C | 6.1°C | 71 | 6.9 | 13.113 h |
| May, selected | 23.0°C12.0°C | 12.0°C | 80 | 7.3 | 14.114 h |
| June | 27.2°C17.6°C | 17.6°C | 121 | 8.3 | 14.615 h |
| July | 28.7°C21.8°C | 21.8°C | 250 | 16.0 | 14.414 h |
| August | 29.1°C22.4°C | 22.4°C | 234 | 15.0 | 13.614 h |
| September | 25.0°C17.1°C | 17.1°C | 137 | 8.1 | 12.512 h |
| October | 19.1°C10.2°C | 10.2°C | 56 | 5.1 | 11.311 h |
| November | 11.7°C3.2°C | 3.2°C | 45 | 6.2 | 10.210 h |
| December | 4.6°C-2.8°C | -2.8°C | 23 | 4.9 | 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
May in nearby cities
- Cheonan in MaySouth Korea · 13 kmHigh 23.5°C · Low 12.3°C · 89 mm rain
- Pyeongtaek in MaySouth Korea · 25 kmHigh 22.9°C · Low 12.0°C · 84 mm rain
- Sejong in MaySouth Korea · 33 kmHigh 23.6°C · Low 12.3°C · 86 mm rain
- Hongseong in MaySouth Korea · 36 kmHigh 22.6°C · Low 12.2°C · 81 mm rain
- Gongju in MaySouth Korea · 38 kmHigh 23.7°C · Low 12.7°C · 84 mm rain
- Osan in MaySouth Korea · 41 kmHigh 22.2°C · Low 11.6°C · 88 mm rain
- Cheongju-si in MaySouth Korea · 46 kmHigh 23.6°C · Low 12.4°C · 90 mm rain
- Seosan in MaySouth Korea · 49 kmHigh 20.3°C · Low 12.2°C · 79 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 Asan) is explained once on the Asan year overview and on the Sources, method and limits page.