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Hourly Forecast
Daylight Hours
06:20
Sunrise
18:31
Sunset
Moon
Waxing Crescent
11:25
Moonrise
21:02
Moonset
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Weather in Seongnam-si tomorrow, September 17, 2026
Expect a muted, overcast feel in Seongnam-si on September 17, 2026 as cloud persists. Brighter breaks, if they arrive, should stay brief. Cloud leads the morning, peaking close to 93% near 11:00. Sunshine has little room until later in the day.
The day peaks near 27°C and cools toward 14°C. Moisture in the air spans 42%-98%, with the highest values around 03:00. Expect gentle winds, highest near 21:00 at 3.4 km/h.
The afternoon keeps an overcast feel, as cloud reaches about 100% around 20:00. Outdoor plans may still want a flexible backup. Visibility stays near 16.1 km. Expect sunrise at 06:20, sunset at 18:29, and 12 hours 8 minutes of sunlight today overall.
The practical takeaway for Seongnam-si on September 17, 2026 is a cloudy day that stays usable, just not particularly bright, around 27°C.
Frequently asked questions about weather in Seongnam-si
How warm does it get in Seongnam-si?
The warmest month in Seongnam-si is August, with average high temperatures of 30°C. The average temperature during this period is around 26°C.
How cold does it get in Seongnam-si?
The coldest month in Seongnam-si is January, with average low temperatures of -7°C. The average temperature during this period is around -2°C.
What is the wettest time of year in Seongnam-si?
The wettest month in Seongnam-si is July, with an average of 306mm of precipitation.
What is the driest time of year in Seongnam-si?
The driest month in Seongnam-si is January, with an average of 23mm of precipitation.
