Gunsan climate

Name: Gunsan
Address: KR

Gunsan is warmest in August, with average highs of 28 °C, and coldest in January, when nights average -2.4 °C. July is the wettest month (256 mm) and January the driest (24 mm). Figures are 1991–2020 climate normals.

Across a full year Gunsan averages 1,159 mm of rain, 74 days above 25 °C and 68 days below freezing.

South Korea · population 264,656 · 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 28 °C
Coldest month January -2.4 °C
Driest month January 24 mm
Wettest month July 256 mm
Least cloud October 46 % cloud
Hottest on record August 36 °C
Coldest on record January -13 °C
Warmest sea August 26 °C

What to expectGunsan through the year

Gunsan has a clear annual cycle: average daily highs run from 3.3 °C in January to 28 °C in August, a swing of 25 °C in mean temperature across the year.

Counted across a normal year, 74 days a year reach 25 °C, 7 of them reach 30 °C, 68 nights drop below freezing. The warmest reading in the 1991–2020 record is 36 °C, in August.

Rain is strongly seasonal. July averages 256 mm against 24 mm in January — 11 times as much. Planning around the dry months matters more here than planning around temperature.

The sea off Gunsan is warmest in August at 26 °C and coldest in February at 5.5 °C. Sea temperature lags the air by a month or two, which is why late summer swims warmer than early summer at the same air temperature.

Month by month

Month	Avg high	Rainfall	Cloud
January	3.3 °C	24 mm	65 %
February	5.0 °C	31 mm	58 %
March	9.3 °C	47 mm	53 %
April	14.9 °C	82 mm	53 %
May	19.9 °C	87 mm	57 %
June	23.9 °C	132 mm	67 %
July	26.8 °C	256 mm	72 %
August	28.0 °C	225 mm	63 %
September	24.4 °C	146 mm	55 %
October	18.9 °C	57 mm	46 %
November	12.1 °C	44 mm	51 %
December	5.7 °C	28 mm	60 %

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	3.3 °C	-2.4 °C	0.5 °C	15.0 °C	-13.0 °C	0	0	25
February	5.0 °C	-1.3 °C	1.8 °C	18.5 °C	-11.2 °C	0	0	20
March	9.3 °C	2.5 °C	5.7 °C	19.9 °C	-5.1 °C	0	0	6
April	14.9 °C	7.8 °C	11.1 °C	26.3 °C	-0.3 °C	0	0	0
May	19.9 °C	13.1 °C	16.4 °C	28.1 °C	6.3 °C	1	0	0
June	23.9 °C	18.1 °C	20.9 °C	30.5 °C	11.6 °C	9	0	0
July	26.8 °C	22.5 °C	24.5 °C	34.0 °C	16.2 °C	24	2	0
August	28.0 °C	23.3 °C	25.5 °C	35.8 °C	16.4 °C	28	5	0
September	24.4 °C	18.6 °C	21.4 °C	31.0 °C	11.1 °C	12	0	0
October	18.9 °C	12.3 °C	15.5 °C	27.6 °C	3.1 °C	0	0	0
November	12.1 °C	5.8 °C	8.9 °C	22.7 °C	-4.6 °C	0	0	1
December	5.7 °C	-0.3 °C	2.8 °C	16.5 °C	-10.2 °C	0	0	17

Rain, sun and wind month by month

Month	Rainfall	Wet days	Daylight	Cloud cover	Humidity	Wind	Sea temp
January	24 mm	5	10.0 h/day	65 %	67 %	19 km/h	7.0 °C
February	31 mm	5	11 h/day	58 %	67 %	19 km/h	5.5 °C
March	47 mm	6	12 h/day	53 %	71 %	20 km/h	6.3 °C
April	82 mm	7	13 h/day	53 %	74 %	20 km/h	9.4 °C
May	87 mm	7	14 h/day	57 %	78 %	18 km/h	13.9 °C
June	132 mm	8	15 h/day	67 %	82 %	17 km/h	18.9 °C
July	256 mm	14	14 h/day	72 %	87 %	18 km/h	22.9 °C
August	225 mm	14	14 h/day	63 %	84 %	16 km/h	25.6 °C
September	146 mm	8	12 h/day	55 %	78 %	16 km/h	23.4 °C
October	57 mm	5	11 h/day	46 %	72 %	16 km/h	19.3 °C
November	44 mm	6	10 h/day	51 %	71 %	18 km/h	14.7 °C
December	28 mm	6	9.7 h/day	60 %	69 %	19 km/h	10.4 °C

How Gunsan 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
Gunsan	28 °C	-2.4 °C	1,159 mm	74
Iksan · South Korea	29 °C	-3.7 °C	1,195 mm	104
Jeonju · South Korea	29 °C	-3.8 °C	1,214 mm	105
Daejeon · South Korea	29 °C	-4.3 °C	1,099 mm	110
Gwangju · South Korea	29 °C	-3.0 °C	1,246 mm	107
Cheongju-si · South Korea	29 °C	-4.9 °C	1,163 mm	110
Pyeongtaek · South Korea	29 °C	-5.4 °C	1,132 mm	106

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

QuestionsCommon questions about Gunsan’s climate

When is the best time to visit Gunsan?

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 Gunsan get?

In August, the warmest month, daily highs average 28 °C. About 7 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 -2.4 °C in January, the coldest month. A normal year has 68 nights below freezing.

Which month is wettest in Gunsan?

July, averaging 256 mm over 14 days with rain. The driest month is January with 24 mm. The year as a whole averages 1,159 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 Gunsan 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: 35.979°, 126.711° (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.