Seoul climate

Name: Seoul
Address: KR

Seoul is warmest in August, with average highs of 29 °C, and coldest in January, when nights average -7.1 °C. July is the wettest month (315 mm) and January the driest (19 mm). Figures are 1991–2020 climate normals.

Across a full year Seoul averages 1,206 mm of rain, 97 days above 25 °C and 114 days below freezing.

South Korea · population 10,349,312 · 1991–2020 normals

Temperature below 0 °C to above 30 °C Rain band height is that month’s share of the wettest month

Warmest month August 29 °C
Coldest month January -7.1 °C
Driest month January 19 mm
Wettest month July 315 mm
Least cloud December 43 % cloud
Hottest on record August 36 °C
Coldest on record January -24 °C

What to expectSeoul through the year

Seoul has a clear annual cycle: average daily highs run from 1.5 °C in January to 29 °C in August, a swing of 28 °C in mean temperature across the year.

Counted across a normal year, 97 days a year reach 25 °C, 18 of them reach 30 °C, 114 nights drop below freezing. The warmest reading in the 1991–2020 record is 36 °C, in August.

Rain is strongly seasonal. July averages 315 mm against 19 mm in January — 17 times as much. Planning around the dry months matters more here than planning around temperature.

Month by month

Month	Avg high	Rainfall	Cloud
January	1.5 °C	19 mm	45 %
February	4.5 °C	27 mm	46 %
March	10.0 °C	37 mm	49 %
April	16.6 °C	70 mm	52 %
May	22.0 °C	95 mm	56 %
June	26.3 °C	134 mm	65 %
July	27.9 °C	315 mm	75 %
August	28.6 °C	263 mm	67 %
September	24.7 °C	123 mm	58 %
October	18.6 °C	54 mm	45 %
November	10.6 °C	46 mm	46 %
December	3.4 °C	23 mm	43 %

Temperature month by month

Month	Avg high	Avg low	Mean	Record high	Record low	Days above 25 °C	Days above 30 °C	Days below 0 °C
January	1.5 °C	-7.1 °C	-3.0 °C	12.9 °C	-24.3 °C	0	0	30
February	4.5 °C	-4.7 °C	-0.5 °C	17.2 °C	-21.3 °C	0	0	26
March	10.0 °C	-0.1 °C	4.5 °C	20.4 °C	-12.1 °C	0	0	17
April	16.6 °C	5.9 °C	10.9 °C	28.1 °C	-2.9 °C	0	0	1
May	22.0 °C	11.9 °C	16.6 °C	31.5 °C	4.8 °C	6	0	0
June	26.3 °C	17.5 °C	21.6 °C	34.2 °C	10.6 °C	21	2	0
July	27.9 °C	21.6 °C	24.4 °C	35.6 °C	13.8 °C	27	6	0
August	28.6 °C	22.0 °C	25.0 °C	36.3 °C	13.1 °C	28	9	0
September	24.7 °C	16.4 °C	20.3 °C	31.8 °C	6.9 °C	14	0	0
October	18.6 °C	9.1 °C	13.6 °C	27.3 °C	-2.8 °C	1	0	0
November	10.6 °C	1.9 °C	6.0 °C	24.0 °C	-13.0 °C	0	0	11
December	3.4 °C	-4.9 °C	-1.0 °C	14.8 °C	-19.8 °C	0	0	28

Rain, sun and wind month by month

Month	Rainfall	Wet days	Daylight	Cloud cover	Humidity	Wind
January	19 mm	4	9.9 h/day	45 %	60 %	15 km/h
February	27 mm	4	11 h/day	46 %	61 %	16 km/h
March	37 mm	6	12 h/day	49 %	66 %	17 km/h
April	70 mm	7	13 h/day	52 %	68 %	18 km/h
May	95 mm	8	14 h/day	56 %	72 %	16 km/h
June	134 mm	9	15 h/day	65 %	75 %	14 km/h
July	315 mm	17	15 h/day	75 %	85 %	15 km/h
August	263 mm	15	14 h/day	67 %	83 %	14 km/h
September	123 mm	8	12 h/day	58 %	77 %	13 km/h
October	54 mm	5	11 h/day	45 %	72 %	14 km/h
November	46 mm	7	10 h/day	46 %	71 %	14 km/h
December	23 mm	5	9.6 h/day	43 %	64 %	15 km/h

How Seoul compares

The same four figures for nearby destinations, so the numbers above have something to be read against. Summer high is the warmest month's average high; winter low is the coldest month's average low.

Destination	Summer high	Winter low	Rain per year	Days above 25 °C
Seoul	29 °C	-7.1 °C	1,206 mm	97
Goyang-si · South Korea	28 °C	-7.2 °C	1,203 mm	91
Bucheon-si · South Korea	28 °C	-6.4 °C	1,153 mm	83
Anyang-si · South Korea	28 °C	-6.1 °C	1,209 mm	84
Seongnam-si · South Korea	28 °C	-6.6 °C	1,294 mm	95
Gunpo · South Korea	28 °C	-6.1 °C	1,139 mm	85
Incheon · South Korea	28 °C	-6.1 °C	1,152 mm	71

Planning a trip? See the best time to visit Seoul.

QuestionsCommon questions about Seoul’s climate

When is the best time to visit Seoul?

That depends on what you want, so the honest answer is a comparison rather than a single month. May, June, September sit closest to 20 °C on average, August is the warmest month and January the driest. The month-by-month table above has the full picture.

How hot does Seoul get?

In August, the warmest month, daily highs average 29 °C. About 18 days a year pass 30 °C. The highest value in the 1991–2020 record is 36 °C.

How cold does it get in winter?

Nights average -7.1 °C in January, the coldest month. A normal year has 114 nights below freezing.

Which month is wettest in Seoul?

July, averaging 315 mm over 17 days with rain. The driest month is January with 19 mm. The year as a whole averages 1,206 mm.

Are these figures a forecast?

No. They are 1991–2020 climate normals: the average of thirty years, which describes what a month is usually like in Seoul rather than what any particular week will bring. Individual years can differ substantially from the normal.

Data sources and method

ERA5 / ERA5-Land reanalysis — Copernicus Climate Change Service (C3S), ECMWF. Copernicus Licence
Open-Meteo — Open-Meteo.com. CC BY 4.0
NOAA OISST v2.1 — NOAA Physical Sciences Laboratory. Public domain
GeoNames — GeoNames.org. CC BY 4.0

Normal period: 1991–2020
Data point: 37.566°, 126.978° (the coordinates the reanalysis values are taken for)
Dataset version: era5-1991-2020-scores1.1
Last processed: 1 August 2026

Measured values come from ERA5 reanalysis and are reproduced unchanged. Calculated by us: monthly rankings, daylight hours, beach and comfort scores. Full formulas are on the methodology page.

Contains modified Copernicus Climate Change Service information 2026. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains.