Koch'ang weather in September
In September, Koch'ang sees average daytime highs of 26°C and overnight lows near 18°C, with 150 mm of rain across 9.5 wet days and about 12.2 hours of daylight. It is the 4th-warmest and 3rd-wettest month of the year here.
Highs ease over the month, from about 27°C in the first days to 24°C by the end. The sky is clear or mostly clear about 35% of the time in September, and the air most often feels muggy.
Daylight stretches from about 12 h 48 min at the start of September to 11 h 42 min by month's end. Set against the rest of the year, September is Koch'ang's 6th-clearest and 11th-windiest month. For the whole year in context, see Koch'ang's year-round climate.
- Daytime high
- 26°
- 4th warmest
- Overnight low
- 18°
- 9th coldest
- Rainfall
- 150 mm
- 9.5 wet days
- Daylight
- 12 h 12 min
- 6:21 AM – 6:34 PM
- Cloud cover
- 56%
- 6th clearest
- Wind
- 8 km/h
- 11th windiest
- Solar energy
- 4.4 kWh/m²
- Travel score
- 6.8
- out of 10
Koch'ang is human settlement in South Korea.
Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.
Temperature in September
Highs ease over the month, from about 27°C in the first days to 24°C by the end.
A typical September day in Koch'ang reaches about 26°C in the afternoon and slips back to 18°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between 22°C and 29°C. Set against its neighbours, September runs about 4°C cooler than August and about 5°C warmer than October.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°C) | 28 | 28 | 27 | 27 | 27 | 27 | 27 | 27 | 27 | 27 | 26 | 26 | 26 | 26 | 26 | 26 | 26 | 25 | 25 | 25 | 25 | 25 | 25 | 24 | 24 | 24 | 24 | 24 | 24 | 23 |
| Avg low (°C) | 21 | 21 | 21 | 20 | 20 | 20 | 20 | 20 | 19 | 19 | 19 | 19 | 19 | 18 | 18 | 18 | 18 | 18 | 17 | 17 | 17 | 17 | 16 | 16 | 16 | 16 | 16 | 15 | 15 | 15 |
| Avg high (°C) | Avg low (°C) | |
|---|---|---|
| 1 | 28 | 21 |
| 2 | 28 | 21 |
| 3 | 27 | 21 |
| 4 | 27 | 20 |
| 5 | 27 | 20 |
| 6 | 27 | 20 |
| 7 | 27 | 20 |
| 8 | 27 | 20 |
| 9 | 27 | 19 |
| 10 | 27 | 19 |
| 11 | 26 | 19 |
| 12 | 26 | 19 |
| 13 | 26 | 19 |
| 14 | 26 | 18 |
| 15 | 26 | 18 |
| 16 | 26 | 18 |
| 17 | 26 | 18 |
| 18 | 25 | 18 |
| 19 | 25 | 17 |
| 20 | 25 | 17 |
| 21 | 25 | 17 |
| 22 | 25 | 17 |
| 23 | 25 | 16 |
| 24 | 24 | 16 |
| 25 | 24 | 16 |
| 26 | 24 | 16 |
| 27 | 24 | 16 |
| 28 | 24 | 15 |
| 29 | 24 | 15 |
| 30 | 23 | 15 |
How September really feels in Koch'ang
Once humidity and wind are folded in, September averages 0 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.
September sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.
Koch'ang weather by month
How September compares with the rest of the year at a glance. September is the 4th-warmest and 3rd-wettest month here — the current month is highlighted below.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | 4° / -3° | 28 | 5.9 | 4.1 | 9.9 | 0.0 |
| Feb | 6° / -2° | 33 | 5.4 | 1.7 | 10.7 | 0.7 |
| Mar | 11° / 2° | 55 | 7.3 | 1 | 11.7 | 3.2 |
| Apr | 17° / 7° | 81 | 7.5 | 0 | 12.9 | 5.9 |
| May | 22° / 13° | 88 | 7.8 | 0 | 13.8 | 7.1 |
| Jun | 26° / 18° | 147 | 9.6 | 0 | 14.3 | 6.6 |
| Jul | 29° / 23° | 238 | 15.6 | 0 | 14.1 | 4.9 |
| Aug | 29° / 23° | 228 | 16 | 0 | 13.3 | 4.6 |
| Sep | 26° / 18° | 150 | 9.5 | 0 | 12.2 | 6.8 |
| Oct | 20° / 11° | 57 | 5.5 | 0 | 11.1 | 7.3 |
| Nov | 14° / 5° | 47 | 6.9 | 0.2 | 10.1 | 4.2 |
| Dec | 7° / -1° | 31 | 6.5 | 2.9 | 9.7 | 0.9 |
Cloud cover in September
The sky is clear or mostly clear about 35% of the time in September.
Beyond those clear spells, partly cloudy skies cover about 16% of September, with mostly cloudy or overcast conditions the remaining 49%. Skies tend to open up as the month goes on.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Clearer (%) | 42 | 44 | 44 | 45 | 46 | 46 | 47 | 48 | 48 | 48 | 49 | 50 | 50 | 50 | 51 | 51 | 52 | 54 | 54 | 54 | 55 | 56 | 56 | 56 | 56 | 56 | 56 | 56 | 57 | 57 |
| Cloudier (%) | 58 | 56 | 56 | 55 | 54 | 54 | 53 | 52 | 52 | 52 | 51 | 50 | 50 | 50 | 49 | 49 | 48 | 46 | 46 | 46 | 45 | 44 | 44 | 44 | 44 | 44 | 44 | 44 | 43 | 43 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| 1 | 42 | 58 |
| 2 | 44 | 56 |
| 3 | 44 | 56 |
| 4 | 45 | 55 |
| 5 | 46 | 54 |
| 6 | 46 | 54 |
| 7 | 47 | 53 |
| 8 | 48 | 52 |
| 9 | 48 | 52 |
| 10 | 48 | 52 |
| 11 | 49 | 51 |
| 12 | 50 | 50 |
| 13 | 50 | 50 |
| 14 | 50 | 50 |
| 15 | 51 | 49 |
| 16 | 51 | 49 |
| 17 | 52 | 48 |
| 18 | 54 | 46 |
| 19 | 54 | 46 |
| 20 | 54 | 46 |
| 21 | 55 | 45 |
| 22 | 56 | 44 |
| 23 | 56 | 44 |
| 24 | 56 | 44 |
| 25 | 56 | 44 |
| 26 | 56 | 44 |
| 27 | 56 | 44 |
| 28 | 56 | 44 |
| 29 | 57 | 43 |
| 30 | 57 | 43 |
Chance of precipitation in September
Koch'ang gets around 150 mm of rain over 9.5 wet days in September. The line is the day-by-day chance of measurable precipitation.
Day to day, the chance of measurable rain averages around 33% and peaks near 45% on the wettest days. The odds ease toward the end of the month.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rain chance (%) | 45 | 44 | 43 | 42 | 41 | 41 | 40 | 39 | 38 | 37 | 36 | 35 | 34 | 33 | 32 | 31 | 30 | 29 | 28 | 27 | 27 | 26 | 26 | 26 | 25 | 25 | 25 | 25 | 24 | 24 |
| Rain chance (%) | |
|---|---|
| 1 | 45 |
| 2 | 44 |
| 3 | 43 |
| 4 | 42 |
| 5 | 41 |
| 6 | 41 |
| 7 | 40 |
| 8 | 39 |
| 9 | 38 |
| 10 | 37 |
| 11 | 36 |
| 12 | 35 |
| 13 | 34 |
| 14 | 33 |
| 15 | 32 |
| 16 | 31 |
| 17 | 30 |
| 18 | 29 |
| 19 | 28 |
| 20 | 27 |
| 21 | 27 |
| 22 | 26 |
| 23 | 26 |
| 24 | 26 |
| 25 | 25 |
| 26 | 25 |
| 27 | 25 |
| 28 | 25 |
| 29 | 24 |
| 30 | 24 |
Humidity in September
Most of September feels muggy — the stacked bands show each day's mix of comfort levels, read off the dew point.
By dew point, September lands in the muggy band about 29% of days. Sticky, muggy-or-worse air turns up on roughly 43% of them.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dry (%) | 0 | 1 | 1 | 1 | 1 | 2 | 2 | 2 | 3 | 4 | 4 | 5 | 6 | 7 | 8 | 9 | 11 | 12 | 13 | 15 | 16 | 18 | 19 | 21 | 23 | 25 | 28 | 30 | 33 | 35 |
| Comfortable (%) | 2 | 3 | 3 | 4 | 5 | 6 | 7 | 8 | 10 | 11 | 13 | 14 | 16 | 18 | 20 | 21 | 23 | 25 | 26 | 27 | 29 | 30 | 31 | 31 | 32 | 32 | 33 | 33 | 32 | 32 |
| Humid (%) | 19 | 20 | 22 | 23 | 24 | 25 | 26 | 26 | 27 | 27 | 27 | 28 | 28 | 28 | 27 | 28 | 27 | 28 | 28 | 28 | 28 | 28 | 28 | 28 | 27 | 27 | 26 | 25 | 24 | 23 |
| Muggy (%) | 40 | 40 | 41 | 41 | 42 | 42 | 42 | 41 | 41 | 40 | 39 | 38 | 36 | 35 | 33 | 32 | 29 | 28 | 26 | 24 | 22 | 20 | 18 | 16 | 15 | 13 | 12 | 11 | 10 | 9 |
| Oppressive (%) | 34 | 32 | 30 | 28 | 26 | 24 | 23 | 21 | 19 | 18 | 16 | 15 | 14 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 5 | 4 | 3 | 3 | 2 | 2 | 2 | 1 | 1 |
| Miserable (%) | 5 | 4 | 3 | 3 | 2 | 2 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Dry (%) | Comfortable (%) | Humid (%) | Muggy (%) | Oppressive (%) | Miserable (%) | |
|---|---|---|---|---|---|---|
| 1 | 0 | 2 | 19 | 40 | 34 | 5 |
| 2 | 1 | 3 | 20 | 40 | 32 | 4 |
| 3 | 1 | 3 | 22 | 41 | 30 | 3 |
| 4 | 1 | 4 | 23 | 41 | 28 | 3 |
| 5 | 1 | 5 | 24 | 42 | 26 | 2 |
| 6 | 2 | 6 | 25 | 42 | 24 | 2 |
| 7 | 2 | 7 | 26 | 42 | 23 | 1 |
| 8 | 2 | 8 | 26 | 41 | 21 | 1 |
| 9 | 3 | 10 | 27 | 41 | 19 | 1 |
| 10 | 4 | 11 | 27 | 40 | 18 | 0 |
| 11 | 4 | 13 | 27 | 39 | 16 | 0 |
| 12 | 5 | 14 | 28 | 38 | 15 | 0 |
| 13 | 6 | 16 | 28 | 36 | 14 | 0 |
| 14 | 7 | 18 | 28 | 35 | 12 | 0 |
| 15 | 8 | 20 | 27 | 33 | 11 | 0 |
| 16 | 9 | 21 | 28 | 32 | 10 | 0 |
| 17 | 11 | 23 | 27 | 29 | 9 | 0 |
| 18 | 12 | 25 | 28 | 28 | 8 | 0 |
| 19 | 13 | 26 | 28 | 26 | 7 | 0 |
| 20 | 15 | 27 | 28 | 24 | 6 | 0 |
| 21 | 16 | 29 | 28 | 22 | 5 | 0 |
| 22 | 18 | 30 | 28 | 20 | 5 | 0 |
| 23 | 19 | 31 | 28 | 18 | 4 | 0 |
| 24 | 21 | 31 | 28 | 16 | 3 | 0 |
| 25 | 23 | 32 | 27 | 15 | 3 | 0 |
| 26 | 25 | 32 | 27 | 13 | 2 | 0 |
| 27 | 28 | 33 | 26 | 12 | 2 | 0 |
| 28 | 30 | 33 | 25 | 11 | 2 | 0 |
| 29 | 33 | 32 | 24 | 10 | 1 | 0 |
| 30 | 35 | 32 | 23 | 9 | 1 | 0 |
Wind in September
Winds average 8 km/h in September.
Across September, daily wind ranges from about 9 km/h on the calmest days to 9 km/h at its breeziest. It stays fairly steady from day to day.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wind speed (km/h) | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 |
| Feels | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm |
| Wind speed (km/h) | Feels | |
|---|---|---|
| 1 | 9 | calm |
| 2 | 9 | calm |
| 3 | 9 | calm |
| 4 | 9 | calm |
| 5 | 9 | calm |
| 6 | 9 | calm |
| 7 | 9 | calm |
| 8 | 9 | calm |
| 9 | 9 | calm |
| 10 | 9 | calm |
| 11 | 9 | calm |
| 12 | 9 | calm |
| 13 | 9 | calm |
| 14 | 9 | calm |
| 15 | 9 | calm |
| 16 | 9 | calm |
| 17 | 9 | calm |
| 18 | 9 | calm |
| 19 | 9 | calm |
| 20 | 9 | calm |
| 21 | 9 | calm |
| 22 | 9 | calm |
| 23 | 9 | calm |
| 24 | 9 | calm |
| 25 | 9 | calm |
| 26 | 9 | calm |
| 27 | 9 | calm |
| 28 | 9 | calm |
| 29 | 9 | calm |
| 30 | 9 | calm |
Sunrise & sunset in September
Daylight runs from about 12 h 48 min at the start of September to 11 h 42 min by month's end. The lit band spans sunrise to sunset each day.
Days shrink by about 66 minutes over September. Sunrise moves from 6:09 AM to 6:32 AM, and sunset from 6:56 PM to 6:13 PM.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight (h) | 12.8 | 12.7 | 12.7 | 12.7 | 12.6 | 12.6 | 12.6 | 12.5 | 12.5 | 12.4 | 12.4 | 12.4 | 12.3 | 12.3 | 12.3 | 12.2 | 12.2 | 12.1 | 12.1 | 12.1 | 12.0 | 12.0 | 12.0 | 11.9 | 11.9 | 11.8 | 11.8 | 11.8 | 11.7 | 11.7 |
| Sunrise (AM) | 6:09 | 6:10 | 6:11 | 6:12 | 6:12 | 6:13 | 6:14 | 6:15 | 6:16 | 6:16 | 6:17 | 6:18 | 6:19 | 6:19 | 6:20 | 6:21 | 6:22 | 6:22 | 6:23 | 6:24 | 6:25 | 6:26 | 6:26 | 6:27 | 6:28 | 6:29 | 6:30 | 6:30 | 6:31 | 6:32 |
| Sunset (PM) | 6:56 | 6:55 | 6:54 | 6:52 | 6:51 | 6:49 | 6:48 | 6:46 | 6:45 | 6:43 | 6:42 | 6:40 | 6:39 | 6:37 | 6:36 | 6:34 | 6:33 | 6:31 | 6:30 | 6:28 | 6:27 | 6:25 | 6:24 | 6:22 | 6:20 | 6:19 | 6:18 | 6:16 | 6:15 | 6:13 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| 1 | 12.8 | 6:09 | 6:56 |
| 2 | 12.7 | 6:10 | 6:55 |
| 3 | 12.7 | 6:11 | 6:54 |
| 4 | 12.7 | 6:12 | 6:52 |
| 5 | 12.6 | 6:12 | 6:51 |
| 6 | 12.6 | 6:13 | 6:49 |
| 7 | 12.6 | 6:14 | 6:48 |
| 8 | 12.5 | 6:15 | 6:46 |
| 9 | 12.5 | 6:16 | 6:45 |
| 10 | 12.4 | 6:16 | 6:43 |
| 11 | 12.4 | 6:17 | 6:42 |
| 12 | 12.4 | 6:18 | 6:40 |
| 13 | 12.3 | 6:19 | 6:39 |
| 14 | 12.3 | 6:19 | 6:37 |
| 15 | 12.3 | 6:20 | 6:36 |
| 16 | 12.2 | 6:21 | 6:34 |
| 17 | 12.2 | 6:22 | 6:33 |
| 18 | 12.1 | 6:22 | 6:31 |
| 19 | 12.1 | 6:23 | 6:30 |
| 20 | 12.1 | 6:24 | 6:28 |
| 21 | 12.0 | 6:25 | 6:27 |
| 22 | 12.0 | 6:26 | 6:25 |
| 23 | 12.0 | 6:26 | 6:24 |
| 24 | 11.9 | 6:27 | 6:22 |
| 25 | 11.9 | 6:28 | 6:20 |
| 26 | 11.8 | 6:29 | 6:19 |
| 27 | 11.8 | 6:30 | 6:18 |
| 28 | 11.8 | 6:30 | 6:16 |
| 29 | 11.7 | 6:31 | 6:15 |
| 30 | 11.7 | 6:32 | 6:13 |
Solar energy in September
Average shortwave solar energy reaching the ground each day in September, about 4.4 kWh/m².
For context, solar energy here swings from a low near 2.24 kWh/m² to a high of 5.93 kWh/m² in May across the year — September's 4.4 kWh/m² falls in the middle.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Solar energy (kWh/m²) | 4.5 | 4.5 | 4.5 | 4.5 | 4.5 | 4.5 | 4.5 | 4.5 | 4.5 | 4.4 | 4.4 | 4.4 | 4.4 | 4.4 | 4.4 | 4.4 | 4.4 | 4.4 | 4.4 | 4.4 | 4.3 | 4.3 | 4.3 | 4.3 | 4.3 | 4.3 | 4.2 | 4.2 | 4.2 | 4.2 |
| Level | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| 1 | 4.5 | Bright |
| 2 | 4.5 | Bright |
| 3 | 4.5 | Bright |
| 4 | 4.5 | Bright |
| 5 | 4.5 | Bright |
| 6 | 4.5 | Bright |
| 7 | 4.5 | Bright |
| 8 | 4.5 | Bright |
| 9 | 4.5 | Bright |
| 10 | 4.4 | Bright |
| 11 | 4.4 | Bright |
| 12 | 4.4 | Bright |
| 13 | 4.4 | Bright |
| 14 | 4.4 | Bright |
| 15 | 4.4 | Bright |
| 16 | 4.4 | Bright |
| 17 | 4.4 | Bright |
| 18 | 4.4 | Bright |
| 19 | 4.4 | Bright |
| 20 | 4.4 | Bright |
| 21 | 4.3 | Bright |
| 22 | 4.3 | Bright |
| 23 | 4.3 | Bright |
| 24 | 4.3 | Bright |
| 25 | 4.3 | Bright |
| 26 | 4.3 | Bright |
| 27 | 4.2 | Bright |
| 28 | 4.2 | Bright |
| 29 | 4.2 | Bright |
| 30 | 4.2 | Bright |
Hazard calendar for Koch'ang
In September, Koch'ang sits inside its pacific typhoon and rainy season season. The full year is below, with each hazard's peak months called out.
Koch'ang sits in the Pacific typhoon belt; the season peaks July–October.
Koch'ang's rainy season runs June–September, when most of the year's rain falls.
Is September a good time to visit Koch'ang?
Our two travel scores rate September for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).
September is a reasonable time to visit Koch'ang for sightseeing. The water and warmth also suit a beach or pool day.
What to pack for Koch'ang in September
From September's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In September, Koch'ang sees daytime highs around 26°C and nights near 18°C. Worth packing: light clothes and rain gear. About 10 days see rain.
Sea temperature near Koch'ang in September
The nearest coast averages about 23°C in September — the other half of the beach question. The full-year curve and swim-comfort zones are below.
The sea at the nearest coast (about 30 km away) is warmest in August at about 25°C and coldest in February near 6°C.
It's comfortable for a long swim from Jun 26 to Oct 11 — about 3.6 months when the water holds above 20°C.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°C) | 8 | 6 | 7 | 10 | 14 | 19 | 23 | 25 | 23 | 19 | 15 | 11 |
| Comfort | Bracing | Bracing | Bracing | Bracing | Bracing | Cool | Refreshing | Warm | Refreshing | Cool | Cool | Bracing |
| Sea temperature (°C) | Comfort | |
|---|---|---|
| Jan | 8 | Bracing |
| Feb | 6 | Bracing |
| Mar | 7 | Bracing |
| Apr | 10 | Bracing |
| May | 14 | Bracing |
| Jun | 19 | Cool |
| Jul | 23 | Refreshing |
| Aug | 25 | Warm |
| Sep | 23 | Refreshing |
| Oct | 19 | Cool |
| Nov | 15 | Cool |
| Dec | 11 | Bracing |
UV index in Koch'ang in September
Clear-sky midday UV in September peaks around 8 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Koch'ang peaks around September 12 at about 8 (very high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near January 1 at about 2 (moderate).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 9 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 2 | 3 | 5 | 7 | 7 | 8 | 8 | 7 | 8 | 5 | 4 | 2 |
| Level | Moderate | Moderate | High | High | Very high | Very high | Very high | Very high | Very high | High | Moderate | Moderate |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 2 | Moderate |
| Feb | 3 | Moderate |
| Mar | 5 | High |
| Apr | 7 | High |
| May | 7 | Very high |
| Jun | 8 | Very high |
| Jul | 8 | Very high |
| Aug | 7 | Very high |
| Sep | 8 | Very high |
| Oct | 5 | High |
| Nov | 4 | Moderate |
| Dec | 2 | Moderate |
Air quality in Koch'ang in September
Average fine-particle pollution (PM2.5) through the year — so you can see where September falls, not just the annual average.
Air quality in Koch'ang is worst in March — around 61 µg/m³ PM2.5 (unhealthy), about 2.1× the cleanest month (August, 28 µg/m³).
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 41 | 48 | 61 | 54 | 45 | 39 | 29 | 28 | 33 | 35 | 38 | 34 |
| Level | Poor | Poor | Unhealthy | Poor | Poor | Poor | Moderate | Moderate | Moderate | Moderate | Poor | Moderate |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 41 | Poor |
| Feb | 48 | Poor |
| Mar | 61 | Unhealthy |
| Apr | 54 | Poor |
| May | 45 | Poor |
| Jun | 39 | Poor |
| Jul | 29 | Moderate |
| Aug | 28 | Moderate |
| Sep | 33 | Moderate |
| Oct | 35 | Moderate |
| Nov | 38 | Poor |
| Dec | 34 | Moderate |
Where is Koch'ang?
Koch'ang sits at 35.4°N, 126.7°E, 44 m above sea level, in South Korea. The nearest listed city is Jangseong, 17 km away.
Topography around Koch'ang
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Koch'ang.
Within 3 km, the terrain around Koch'ang has significant variations in elevation — a maximum elevation change of 403 m around an average of 91 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 730 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,720 m.
The land around Koch'ang is covered by trees (48%) and cropland (29%) within 3 km, trees (57%) and cropland (31%) within 16 km, and trees (40%), water (34%) and cropland (21%) within 80 km.
South Korea travel facts
- Travel advisory
- Level 1
- Exercise Normal Precautions
- Power plugs
- Type C / F
- 220 V · 60 Hz
- Prices
- ≈ 57% of US
- price level, 2025
- GDP per capita
- $36,227
- 2025
- Happiness
- 6.0 / 10
- World Happiness, 2025
- Safe drinking water
- 99%
- of population, 2024
- Homicide rate
- 0.5
- per 100k, 2023
- Road deaths
- 8.6
- per 100k/yr, 2019
- Income group
- High
- World Bank
- English
- Moderate
- EF EPI 522
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Koch'ang (35.4333°, 126.7°, elevation 44 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).