nomadseason

Monthly climate in Seongnam-si, South Korea

Last updated: July 31, 2025

Under the Köppen–Geiger climate classification Seongnam-si features a humid continental climate (Dwa). Temperatures typically range between -3 °C (28 °F) and 26 °C (79 °F) through the year, but rarely can drop to -19 °C (-2 °F) or can rise to as high as 38 °C (100 °F). The average annual precipitation amounts to about 1226 mm (48.3 inches) and receives 91 rainy days on the 1 mm (0.04 inches) threshold annually. Seongnam-si enjoys an average of 3145 hours of sunshine throughout the year, and daylight varies from 9 hours 36 minutes to 14 hours 41 minutes per day.

Monthly average temperatures in Seongnam-si, South Korea

The warmest months in Seongnam-si are June, July and August, with daily mean temperatures ranging from 22 to 26 °C (72 - 79 °F) throughout the day. The coldest temperatures usually occur in January, February and December, when daily mean temperatures range from -3 to 0 °C (28 - 32 °F) throughout the day. On average each year, Seongnam-si experiences 95 days above 25 °C (77.0 °F) and 99 days below 0 °C (32.0 °F).

Monthly average temperatures with daily means, minimums and maximums for period, average high and low temperatures in Seongnam-si. Generated using Copernicus Climate Change Service information. Data for period from January 2017 to June 2022.
 JanFebMarAprMayJunJulAugSepOctNovDec
Maximum12°C
(54°F)		18°C
(65°F)		21°C
(70°F)		27°C
(81°F)		32°C
(90°F)		34°C
(94°F)		35°C
(96°F)		38°C
(100°F)		30°C
(86°F)		28°C
(83°F)		20°C
(69°F)		12°C
(54°F)
Mean maximum10°C
(50°F)		13°C
(55°F)		19°C
(66°F)		26°C
(79°F)		30°C
(86°F)		31°C
(88°F)		34°C
(93°F)		35°C
(95°F)		29°C
(84°F)		26°C
(80°F)		19°C
(67°F)		11°C
(52°F)
Average high2°C
(37°F)		5°C
(41°F)		12°C
(54°F)		18°C
(64°F)		23°C
(74°F)		27°C
(81°F)		29°C
(85°F)		30°C
(86°F)		25°C
(78°F)		20°C
(68°F)		12°C
(54°F)		4°C
(39°F)
Daily mean-3°C
(28°F)		-0°C
(32°F)		6°C
(44°F)		12°C
(54°F)		17°C
(64°F)		22°C
(72°F)		25°C
(78°F)		26°C
(79°F)		21°C
(70°F)		14°C
(58°F)		7°C
(44°F)		-1°C
(31°F)
Average low-7°C
(20°F)		-5°C
(23°F)		1°C
(34°F)		6°C
(43°F)		12°C
(53°F)		17°C
(64°F)		22°C
(72°F)		23°C
(73°F)		17°C
(62°F)		9°C
(49°F)		2°C
(35°F)		-5°C
(23°F)
Mean minimum-15°C
(6°F)		-12°C
(11°F)		-4°C
(24°F)		-0°C
(32°F)		6°C
(43°F)		13°C
(56°F)		18°C
(65°F)		18°C
(65°F)		11°C
(52°F)		1°C
(34°F)		-5°C
(23°F)		-14°C
(8°F)
Minimum-19°C
(-2°F)		-15°C
(6°F)		-7°C
(20°F)		-1°C
(30°F)		5°C
(41°F)		12°C
(54°F)		17°C
(63°F)		15°C
(59°F)		9°C
(48°F)		-1°C
(30°F)		-7°C
(20°F)		-16°C
(4°F)

Compare climate in Seongnam-si with other places

Compare temperature, precipitation, sunshine, UV index in Seongnam-si, South Korea with other places around the world.

Monthly average precipitation in Seongnam-si, South Korea

Seongnam-si usually has the most precipitation in July, August and September, with an average of 13 rainy days and 235 mm (9.3 inches) of precipitation per month. The driest months in Seongnam-si are January, February and December. On average, 23 mm (0.9 inches) of precipitation falls during these months.

Monthly average precipitation and precipitation days in Seongnam-si. Generated using Copernicus Climate Change Service information. Data for period from January 2017 to January 2022.
 JanFebMarAprMayJunJulAugSepOctNovDec
Average precipitation mm (inches)22 (0.9)24 (0.9)53 (2.1)67 (2.7)117 (4.6)94 (3.7)278 (10.9)285 (11.2)142 (5.6)65 (2.5)56 (2.2)23 (0.9)
Average precipitation days (≥ 1 mm)24569915179654

Monthly sunshine hours in Seongnam-si, South Korea

The sunniest months in Seongnam-si are May, June and July, when the sun shines an average of 9 hours 45 minutes a day. Least sunny months in Seongnam-si: January, November and December receive an average of 7 hours 10 minutes of sunshine daily.

Mean monthly sunshine duration, average sunshine hours per day and mean daily daylight hours in Seongnam-si. Generated using Copernicus Atmosphere Monitoring Service information. Data for period from January 2017 to January 2022.
 JanFebMarAprMayJunJulAugSepOctNovDec
Mean monthly sunshine hours197239276281305310282274256257228233
Mean daily daylight hours9h 53m10h 47m11h 57m13h 9m14h 10m14h 41m14h 25m13h 32m12h 23m11h 11m10h 9m9h 36m

Solar UV radiation in Seongnam-si, South Korea

Seongnam-si experiences the highest level of ultraviolet (UV) radiation in June, July and August, when the maximum UV index can reach values of 10 - 11, which corresponds to the Very High / Extreme category of sun exposure. January, February and December are in the Moderate exposure category. In these months, the maximum values of the UV index do not exceed 4. For more detailed information, check out our hourly Seongnam-si UV Index data.

Average daily maximum UV levels by month for Seongnam-si. Generated using Copernicus Atmosphere Monitoring Service information. Data for period from January 2022 to January 2023.
 JanFebMarAprMayJunJulAugSepOctNovDec
UV Index (month maximum)346891011119643