Climate averages 1991–2020
Hyesan weather
by month.
See how the year changes. July has the highest average daily maximum; January has the lowest average monthly precipitation.
Pleasant-weather months by our simple rule: September
Long-term climate patterns, not a forecast for a particular trip.
Across the year Hyesan averages a daytime high of 9.9°C and a nighttime low of -1.3°C, with about 778 mm of precipitation on roughly 116 days. July is the warmest month (average high 24.9°C) and January the coolest (-8.0°C). July is the wettest month with 164 mm; January is the driest with 10 mm.
Months with pleasant weather by a simple rule (average high between 18°C and 29°C, average low of at least 5°C and at most 8 rain days): September. This looks at temperature and rain only, not humidity, wind, sea temperature or crowds.
The annual picture
A year in Hyesan
Monthly precipitation
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
Hyesan climate table
| Month | Average highHigh / low | Average low | Precipitation mm/month | Wet days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | -8.0°C-20.9°C | -20.9°C | 10 | 3.1 | 9.610 h |
| February | -4.2°C-17.6°C | -17.6°C | 18 | 4.6 | 10.611 h |
| March | 2.3°C-9.2°C | -9.2°C | 33 | 7.9 | 11.912 h |
| April | 11.0°C-0.4°C | -0.4°C | 56 | 10.5 | 13.313 h |
| May | 18.0°C5.5°C | 5.5°C | 95 | 14.9 | 14.514 h |
| June | 22.3°C11.2°C | 11.2°C | 97 | 15.5 | 15.115 h |
| July | 24.9°C15.4°C | 15.4°C | 164 | 17.3 | 14.815 h |
| August | 24.4°C15.1°C | 15.1°C | 136 | 14.2 | 13.814 h |
| September | 19.7°C8.8°C | 8.8°C | 70 | 7.9 | 12.513 h |
| October | 12.1°C1.3°C | 1.3°C | 43 | 7.6 | 11.111 h |
| November | 2.5°C-7.5°C | -7.5°C | 38 | 7.7 | 9.910 h |
| December | -6.0°C-18.0°C | -18.0°C | 18 | 5.2 | 9.29 h |
Precipitation (rain or snow, as water) is the average of the 30 separate monthly totals. A wet 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
Nearby cities
- Changam-ch’onNorth Korea · 102 kmHigh 13.9°C · Low 4.1°C · 824 mm precipitation a year
- HwasŏngNorth Korea · 111 kmHigh 12.4°C · Low 3.2°C · 848 mm precipitation a year
- Myŏnggan-dongNorth Korea · 114 kmHigh 12.1°C · Low 3.2°C · 848 mm precipitation a year
- ŎrangNorth Korea · 123 kmHigh 11.7°C · Low 4.5°C · 900 mm precipitation a year
- ChongjinNorth Korea · 140 kmHigh 10.7°C · Low 4.0°C · 1,059 mm precipitation a year
- KanggyeNorth Korea · 142 kmHigh 12.2°C · Low 1.1°C · 1,085 mm precipitation a year
- HelongChina · 144 kmHigh 11.1°C · Low -0.1°C · 819 mm precipitation a year
- Sinp’oNorth Korea · 151 kmHigh 12.6°C · Low 7.0°C · 880 mm rain a year
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 limitsWhat do the high and low temperatures mean?
We average the daily maximum and daily minimum for each calendar month over 1991–2020. They are not record extremes, a forecast range or temperatures at a fixed time of day.
How is a rain day counted?
A local calendar day (standard time, UTC+9, no daylight saving) with at least 1 mm of total precipitation counts as one rain day. We count these for each year and month, then average across 30 years. The average does not predict which days will be wet.
Where do the numbers come from?
ERA5-Land (temperature) and ERA5 (precipitation) reanalysis from the Copernicus Climate Change Service, read from the Open-Meteo open-data archive. Temperature comes from the 0.1° model cell at 41.40°, 128.20° (2 km from the city centre), adjusted up by 1.4°C for the difference between the city's elevation (709 m) and the cell's (928 m). Rain comes from the 0.25° cell at 41.50°, 128.25°. These are model estimates, not weather-station readings; coast, hills and city streets can differ.
Does this page show sunshine, humidity or sea temperature?
No. The data used here contain air temperature and precipitation only. Daylight hours are calculated from the city's latitude (sunrise to sunset), not measured sunshine.