Seongnam-si weather in September
In September, Seongnam-si sees average daytime highs of 25°C and overnight lows near 16°C, with 134 mm of rain across 8.4 wet days and about 12.3 hours of daylight. It is the 4th-warmest and 4th-wettest month of the year here.
Highs ease over the month, from about 27°C in the first days to 23°C by the end. The sky is clear or mostly clear about 34% of the time in September, and the air most often feels humid.
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 Seongnam-si's 9th-clearest and 12th-windiest month. For the whole year in context, see Seongnam-si's year-round climate.
- Daytime high
- 25°
- 4th warmest
- Overnight low
- 16°
- 9th coldest
- Rainfall
- 134 mm
- 8.4 wet days
- Daylight
- 12 h 12 min
- 6:19 AM – 6:33 PM
- Cloud cover
- 58%
- 9th clearest
- Wind
- 7 km/h
- 12th windiest
- Solar energy
- 4.15 kWh/m²
- Travel score
- 6.9
- out of 10
Seongnam-si 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 23°C by the end.
A typical September day in Seongnam-si reaches about 25°C in the afternoon and slips back to 16°C overnight — a 9°C spread between the day's warmth and the night's chill. On most days the high lands between 21°C and 28°C. Set against its neighbours, September runs about 4°C cooler than August and about 6°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) | 27 | 27 | 27 | 27 | 27 | 27 | 26 | 26 | 26 | 26 | 26 | 26 | 26 | 25 | 25 | 25 | 25 | 25 | 25 | 25 | 24 | 24 | 24 | 24 | 24 | 23 | 23 | 23 | 23 | 23 |
| Avg low (°C) | 19 | 19 | 19 | 19 | 18 | 18 | 18 | 18 | 18 | 17 | 17 | 17 | 17 | 16 | 16 | 16 | 16 | 16 | 15 | 15 | 15 | 15 | 14 | 14 | 14 | 14 | 13 | 13 | 13 | 13 |
| Avg high (°C) | Avg low (°C) | |
|---|---|---|
| 1 | 27 | 19 |
| 2 | 27 | 19 |
| 3 | 27 | 19 |
| 4 | 27 | 19 |
| 5 | 27 | 18 |
| 6 | 27 | 18 |
| 7 | 26 | 18 |
| 8 | 26 | 18 |
| 9 | 26 | 18 |
| 10 | 26 | 17 |
| 11 | 26 | 17 |
| 12 | 26 | 17 |
| 13 | 26 | 17 |
| 14 | 25 | 16 |
| 15 | 25 | 16 |
| 16 | 25 | 16 |
| 17 | 25 | 16 |
| 18 | 25 | 16 |
| 19 | 25 | 15 |
| 20 | 25 | 15 |
| 21 | 24 | 15 |
| 22 | 24 | 15 |
| 23 | 24 | 14 |
| 24 | 24 | 14 |
| 25 | 24 | 14 |
| 26 | 23 | 14 |
| 27 | 23 | 13 |
| 28 | 23 | 13 |
| 29 | 23 | 13 |
| 30 | 23 | 13 |
How September really feels in Seongnam-si
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.
Seongnam-si weather by month
How September compares with the rest of the year at a glance. September is the 4th-warmest and 4th-wettest month here — the current month is highlighted below.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | 2° / -7° | 21 | 3.8 | 2.6 | 9.7 | 0.0 |
| Feb | 5° / -5° | 28 | 4.2 | 2 | 10.6 | 0.3 |
| Mar | 11° / -0° | 43 | 6.4 | 1.6 | 11.7 | 2.8 |
| Apr | 17° / 6° | 79 | 7.3 | 0.1 | 12.9 | 5.9 |
| May | 23° / 12° | 104 | 8.5 | 0 | 14 | 7.1 |
| Jun | 26° / 17° | 135 | 9.3 | 0 | 14.5 | 6.5 |
| Jul | 28° / 21° | 340 | 17.2 | 0 | 14.3 | 4.8 |
| Aug | 29° / 22° | 277 | 15.7 | 0 | 13.4 | 4.8 |
| Sep | 25° / 16° | 134 | 8.4 | 0 | 12.3 | 6.9 |
| Oct | 19° / 9° | 58 | 5.5 | 0 | 11 | 7.0 |
| Nov | 11° / 2° | 50 | 7.3 | 0.7 | 10 | 3.1 |
| Dec | 4° / -5° | 25 | 4.7 | 2.1 | 9.5 | 0.1 |
Cloud cover in September
The sky is clear or mostly clear about 34% 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 50%. 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 (%) | 44 | 44 | 45 | 45 | 46 | 46 | 46 | 47 | 47 | 47 | 47 | 47 | 48 | 49 | 50 | 50 | 51 | 51 | 51 | 53 | 53 | 53 | 54 | 54 | 54 | 54 | 55 | 56 | 56 | 57 |
| Cloudier (%) | 56 | 56 | 55 | 55 | 54 | 54 | 54 | 53 | 53 | 53 | 53 | 53 | 52 | 51 | 50 | 50 | 49 | 49 | 49 | 47 | 47 | 47 | 46 | 46 | 46 | 46 | 45 | 44 | 44 | 43 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| 1 | 44 | 56 |
| 2 | 44 | 56 |
| 3 | 45 | 55 |
| 4 | 45 | 55 |
| 5 | 46 | 54 |
| 6 | 46 | 54 |
| 7 | 46 | 54 |
| 8 | 47 | 53 |
| 9 | 47 | 53 |
| 10 | 47 | 53 |
| 11 | 47 | 53 |
| 12 | 47 | 53 |
| 13 | 48 | 52 |
| 14 | 49 | 51 |
| 15 | 50 | 50 |
| 16 | 50 | 50 |
| 17 | 51 | 49 |
| 18 | 51 | 49 |
| 19 | 51 | 49 |
| 20 | 53 | 47 |
| 21 | 53 | 47 |
| 22 | 53 | 47 |
| 23 | 54 | 46 |
| 24 | 54 | 46 |
| 25 | 54 | 46 |
| 26 | 54 | 46 |
| 27 | 55 | 45 |
| 28 | 56 | 44 |
| 29 | 56 | 44 |
| 30 | 57 | 43 |
Chance of precipitation in September
Seongnam-si gets around 134 mm of rain over 8.4 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 29% and peaks near 42% 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 (%) | 42 | 41 | 40 | 38 | 37 | 36 | 35 | 33 | 33 | 32 | 31 | 30 | 30 | 29 | 29 | 28 | 27 | 27 | 26 | 25 | 24 | 24 | 23 | 23 | 23 | 22 | 22 | 21 | 21 | 20 |
| Rain chance (%) | |
|---|---|
| 1 | 42 |
| 2 | 41 |
| 3 | 40 |
| 4 | 38 |
| 5 | 37 |
| 6 | 36 |
| 7 | 35 |
| 8 | 33 |
| 9 | 33 |
| 10 | 32 |
| 11 | 31 |
| 12 | 30 |
| 13 | 30 |
| 14 | 29 |
| 15 | 29 |
| 16 | 28 |
| 17 | 27 |
| 18 | 27 |
| 19 | 26 |
| 20 | 25 |
| 21 | 24 |
| 22 | 24 |
| 23 | 23 |
| 24 | 23 |
| 25 | 23 |
| 26 | 22 |
| 27 | 22 |
| 28 | 21 |
| 29 | 21 |
| 30 | 20 |
Humidity in September
Most of September feels humid — the stacked bands show each day's mix of comfort levels, read off the dew point.
By dew point, September lands in the humid band about 27% of days. Sticky, muggy-or-worse air turns up on roughly 26% 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 (%) | 1 | 2 | 2 | 3 | 3 | 4 | 5 | 6 | 7 | 9 | 10 | 12 | 14 | 16 | 18 | 20 | 22 | 24 | 26 | 28 | 30 | 32 | 35 | 37 | 39 | 42 | 45 | 47 | 50 | 52 |
| Comfortable (%) | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 18 | 19 | 20 | 22 | 23 | 25 | 26 | 28 | 29 | 30 | 32 | 33 | 34 | 35 | 35 | 36 | 36 | 36 | 35 | 35 | 34 | 33 | 32 |
| Humid (%) | 29 | 31 | 32 | 33 | 34 | 35 | 35 | 35 | 36 | 35 | 35 | 34 | 33 | 32 | 31 | 30 | 29 | 27 | 26 | 25 | 24 | 22 | 21 | 20 | 19 | 17 | 16 | 15 | 14 | 13 |
| Muggy (%) | 36 | 35 | 34 | 33 | 33 | 32 | 31 | 30 | 29 | 28 | 26 | 25 | 23 | 22 | 20 | 18 | 17 | 15 | 13 | 12 | 10 | 9 | 8 | 7 | 6 | 5 | 5 | 4 | 3 | 3 |
| Oppressive (%) | 23 | 21 | 19 | 17 | 16 | 14 | 12 | 11 | 9 | 8 | 7 | 6 | 5 | 4 | 4 | 3 | 3 | 2 | 2 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 |
| Miserable (%) | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 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 | 1 | 10 | 29 | 36 | 23 | 1 |
| 2 | 2 | 11 | 31 | 35 | 21 | 1 |
| 3 | 2 | 12 | 32 | 34 | 19 | 1 |
| 4 | 3 | 13 | 33 | 33 | 17 | 1 |
| 5 | 3 | 14 | 34 | 33 | 16 | 0 |
| 6 | 4 | 15 | 35 | 32 | 14 | 0 |
| 7 | 5 | 16 | 35 | 31 | 12 | 0 |
| 8 | 6 | 18 | 35 | 30 | 11 | 0 |
| 9 | 7 | 19 | 36 | 29 | 9 | 0 |
| 10 | 9 | 20 | 35 | 28 | 8 | 0 |
| 11 | 10 | 22 | 35 | 26 | 7 | 0 |
| 12 | 12 | 23 | 34 | 25 | 6 | 0 |
| 13 | 14 | 25 | 33 | 23 | 5 | 0 |
| 14 | 16 | 26 | 32 | 22 | 4 | 0 |
| 15 | 18 | 28 | 31 | 20 | 4 | 0 |
| 16 | 20 | 29 | 30 | 18 | 3 | 0 |
| 17 | 22 | 30 | 29 | 17 | 3 | 0 |
| 18 | 24 | 32 | 27 | 15 | 2 | 0 |
| 19 | 26 | 33 | 26 | 13 | 2 | 0 |
| 20 | 28 | 34 | 25 | 12 | 1 | 0 |
| 21 | 30 | 35 | 24 | 10 | 1 | 0 |
| 22 | 32 | 35 | 22 | 9 | 1 | 0 |
| 23 | 35 | 36 | 21 | 8 | 1 | 0 |
| 24 | 37 | 36 | 20 | 7 | 1 | 0 |
| 25 | 39 | 36 | 19 | 6 | 0 | 0 |
| 26 | 42 | 35 | 17 | 5 | 0 | 0 |
| 27 | 45 | 35 | 16 | 5 | 0 | 0 |
| 28 | 47 | 34 | 15 | 4 | 0 | 0 |
| 29 | 50 | 33 | 14 | 3 | 0 | 0 |
| 30 | 52 | 32 | 13 | 3 | 0 | 0 |
Wind in September
Winds average 7 km/h in September, the calmest month.
Across September, daily wind ranges from about 7 km/h on the calmest days to 7 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) | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 |
| 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 | 7 | calm |
| 2 | 7 | calm |
| 3 | 7 | calm |
| 4 | 7 | calm |
| 5 | 7 | calm |
| 6 | 7 | calm |
| 7 | 7 | calm |
| 8 | 7 | calm |
| 9 | 7 | calm |
| 10 | 7 | calm |
| 11 | 7 | calm |
| 12 | 7 | calm |
| 13 | 7 | calm |
| 14 | 7 | calm |
| 15 | 7 | calm |
| 16 | 7 | calm |
| 17 | 7 | calm |
| 18 | 7 | calm |
| 19 | 7 | calm |
| 20 | 7 | calm |
| 21 | 7 | calm |
| 22 | 7 | calm |
| 23 | 7 | calm |
| 24 | 7 | calm |
| 25 | 7 | calm |
| 26 | 7 | calm |
| 27 | 7 | calm |
| 28 | 7 | calm |
| 29 | 7 | calm |
| 30 | 7 | 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 6:06 AM to 6:31 AM, and sunset from 6:56 PM to 6:11 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 | 12.8 | 12.8 | 12.7 | 12.7 | 12.6 | 12.6 | 12.6 | 12.5 | 12.5 | 12.4 | 12.4 | 12.4 | 12.3 | 12.3 | 12.2 | 12.2 | 12.2 | 12.1 | 12.1 | 12.0 | 12.0 | 11.9 | 11.9 | 11.9 | 11.8 | 11.8 | 11.7 | 11.7 | 11.7 |
| Sunrise (AM) | 6:06 | 6:07 | 6:08 | 6:08 | 6:09 | 6:10 | 6:11 | 6:12 | 6:13 | 6:14 | 6:14 | 6:15 | 6:16 | 6:17 | 6:18 | 6:19 | 6:20 | 6:20 | 6:21 | 6:22 | 6:23 | 6:24 | 6:25 | 6:26 | 6:26 | 6:27 | 6:28 | 6:29 | 6:30 | 6:31 |
| Sunset (PM) | 6:56 | 6:55 | 6:53 | 6:52 | 6:50 | 6:49 | 6:47 | 6:46 | 6:44 | 6:42 | 6:41 | 6:39 | 6:38 | 6:36 | 6:34 | 6:33 | 6:31 | 6:30 | 6:28 | 6:26 | 6:25 | 6:23 | 6:22 | 6:20 | 6:18 | 6:17 | 6:15 | 6:14 | 6:12 | 6:11 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| 1 | 12.8 | 6:06 | 6:56 |
| 2 | 12.8 | 6:07 | 6:55 |
| 3 | 12.8 | 6:08 | 6:53 |
| 4 | 12.7 | 6:08 | 6:52 |
| 5 | 12.7 | 6:09 | 6:50 |
| 6 | 12.6 | 6:10 | 6:49 |
| 7 | 12.6 | 6:11 | 6:47 |
| 8 | 12.6 | 6:12 | 6:46 |
| 9 | 12.5 | 6:13 | 6:44 |
| 10 | 12.5 | 6:14 | 6:42 |
| 11 | 12.4 | 6:14 | 6:41 |
| 12 | 12.4 | 6:15 | 6:39 |
| 13 | 12.4 | 6:16 | 6:38 |
| 14 | 12.3 | 6:17 | 6:36 |
| 15 | 12.3 | 6:18 | 6:34 |
| 16 | 12.2 | 6:19 | 6:33 |
| 17 | 12.2 | 6:20 | 6:31 |
| 18 | 12.2 | 6:20 | 6:30 |
| 19 | 12.1 | 6:21 | 6:28 |
| 20 | 12.1 | 6:22 | 6:26 |
| 21 | 12.0 | 6:23 | 6:25 |
| 22 | 12.0 | 6:24 | 6:23 |
| 23 | 11.9 | 6:25 | 6:22 |
| 24 | 11.9 | 6:26 | 6:20 |
| 25 | 11.9 | 6:26 | 6:18 |
| 26 | 11.8 | 6:27 | 6:17 |
| 27 | 11.8 | 6:28 | 6:15 |
| 28 | 11.7 | 6:29 | 6:14 |
| 29 | 11.7 | 6:30 | 6:12 |
| 30 | 11.7 | 6:31 | 6:11 |
Solar energy in September
Average shortwave solar energy reaching the ground each day in September, about 4.15 kWh/m².
For context, solar energy here swings from a low near 2.35 kWh/m² to a high of 5.75 kWh/m² in May across the year — September's 4.15 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) | 4.2 | 4.2 | 4.2 | 4.2 | 4.2 | 4.2 | 4.2 | 4.2 | 4.2 | 4.2 | 4.2 | 4.2 | 4.2 | 4.2 | 4.2 | 4.2 | 4.2 | 4.1 | 4.1 | 4.1 | 4.1 | 4.1 | 4.1 | 4.1 | 4.1 | 4.0 | 4.0 | 4.0 | 4.0 | 4.0 |
| 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 | Moderate |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| 1 | 4.2 | Bright |
| 2 | 4.2 | Bright |
| 3 | 4.2 | Bright |
| 4 | 4.2 | Bright |
| 5 | 4.2 | Bright |
| 6 | 4.2 | Bright |
| 7 | 4.2 | Bright |
| 8 | 4.2 | Bright |
| 9 | 4.2 | Bright |
| 10 | 4.2 | Bright |
| 11 | 4.2 | Bright |
| 12 | 4.2 | Bright |
| 13 | 4.2 | Bright |
| 14 | 4.2 | Bright |
| 15 | 4.2 | Bright |
| 16 | 4.2 | Bright |
| 17 | 4.2 | Bright |
| 18 | 4.1 | Bright |
| 19 | 4.1 | Bright |
| 20 | 4.1 | Bright |
| 21 | 4.1 | Bright |
| 22 | 4.1 | Bright |
| 23 | 4.1 | Bright |
| 24 | 4.1 | Bright |
| 25 | 4.1 | Bright |
| 26 | 4.0 | Bright |
| 27 | 4.0 | Bright |
| 28 | 4.0 | Bright |
| 29 | 4.0 | Bright |
| 30 | 4.0 | Moderate |
Hazard calendar for Seongnam-si
In September, Seongnam-si sits inside its pacific typhoon season. The full year is below, with each hazard's peak months called out.
Seongnam-si sits in the Pacific typhoon belt; the season peaks July–October.
Seongnam-si's rainy season runs July–August, when most of the year's rain falls.
Is September a good time to visit Seongnam-si?
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 Seongnam-si for sightseeing. The water and warmth also suit a beach or pool day.
What to pack for Seongnam-si in September
From September's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In September, Seongnam-si sees daytime highs around 25°C and nights near 16°C. Worth packing: light clothes and rain gear. About 8 days see rain.
Sea temperature near Seongnam-si 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 46 km away) is warmest in August at about 24°C and coldest in February near 4°C.
It's comfortable for a long swim from Jul 11 to Oct 13 — about 3.1 months when the water holds above 20°C.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°C) | 6 | 4 | 5 | 8 | 12 | 17 | 21 | 24 | 23 | 20 | 15 | 10 |
| Comfort | Bracing | Bracing | Bracing | Bracing | Bracing | Cool | Refreshing | Refreshing | Refreshing | Cool | Bracing | Bracing |
| Sea temperature (°C) | Comfort | |
|---|---|---|
| Jan | 6 | Bracing |
| Feb | 4 | Bracing |
| Mar | 5 | Bracing |
| Apr | 8 | Bracing |
| May | 12 | Bracing |
| Jun | 17 | Cool |
| Jul | 21 | Refreshing |
| Aug | 24 | Refreshing |
| Sep | 23 | Refreshing |
| Oct | 20 | Cool |
| Nov | 15 | Bracing |
| Dec | 10 | Bracing |
UV index in Seongnam-si in September
Clear-sky midday UV in September peaks around 7 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Seongnam-si peaks around August 11 at about 8 (very high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near December 23 at about 2 (low).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 2 | 3 | 4 | 6 | 6 | 7 | 8 | 8 | 7 | 5 | 3 | 2 |
| Level | Low | Moderate | Moderate | High | High | High | Very high | Very high | Very high | Moderate | Moderate | Low |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 2 | Low |
| Feb | 3 | Moderate |
| Mar | 4 | Moderate |
| Apr | 6 | High |
| May | 6 | High |
| Jun | 7 | High |
| Jul | 8 | Very high |
| Aug | 8 | Very high |
| Sep | 7 | Very high |
| Oct | 5 | Moderate |
| Nov | 3 | Moderate |
| Dec | 2 | Low |
Air quality in Seongnam-si 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 Seongnam-si is worst in March — around 123 µg/m³ PM2.5 (unhealthy), and holds fairly steady the rest of the year.
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 106 | 108 | 123 | 104 | 96 | 91 | 79 | 78 | 97 | 115 | 118 | 100 |
| Level | Unhealthy | Unhealthy | Unhealthy | Unhealthy | Unhealthy | Unhealthy | Unhealthy | Unhealthy | Unhealthy | Unhealthy | Unhealthy | Unhealthy |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 106 | Unhealthy |
| Feb | 108 | Unhealthy |
| Mar | 123 | Unhealthy |
| Apr | 104 | Unhealthy |
| May | 96 | Unhealthy |
| Jun | 91 | Unhealthy |
| Jul | 79 | Unhealthy |
| Aug | 78 | Unhealthy |
| Sep | 97 | Unhealthy |
| Oct | 115 | Unhealthy |
| Nov | 118 | Unhealthy |
| Dec | 100 | Unhealthy |
Where is Seongnam-si?
Seongnam-si sits at 37.4°N, 127.1°E, 80 m above sea level, in South Korea. The nearest listed city is Gwangju, 11 km away.
Topography around Seongnam-si
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Seongnam-si.
Within 3 km, the terrain around Seongnam-si has only modest variations in elevation — a maximum elevation change of 205 m around an average of 64 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 645 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,443 m.
The land around Seongnam-si is covered by artificial surfaces (58%) and trees (34%) within 3 km, trees (58%) and artificial surfaces (33%) within 16 km, and trees (53%) 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 Seongnam-si (37.4386°, 127.1378°, elevation 80 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).