Yokosuka climate

Name: Yokosuka
Address: JP

Yokosuka is warmest in August, with average highs of 27 °C, and coldest in January, when nights average 4.3 °C. October is the wettest month (210 mm) and December the driest (65 mm). Figures are 1991–2020 climate normals.

Across a full year Yokosuka averages 1,517 mm of rain, 70 days above 25 °C and 1 days below freezing.

Japan · population 409,478 · 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 27 °C
Coldest month January 4.3 °C
Driest month December 65 mm
Wettest month October 210 mm
Least cloud January 43 % cloud
Hottest on record August 33 °C
Coldest on record January -2.6 °C
Warmest sea August 26 °C

What to expectYokosuka through the year

Yokosuka has a clear annual cycle: average daily highs run from 9.1 °C in January to 27 °C in August, a swing of 19 °C in mean temperature across the year.

Counted across a normal year, 70 days a year reach 25 °C, 1 of them reach 30 °C, 1 nights drop below freezing. The warmest reading in the 1991–2020 record is 33 °C, in August.

Rain is strongly seasonal. October averages 210 mm against 65 mm in December — 3.2 times as much. Planning around the dry months matters more here than planning around temperature.

The sea off Yokosuka is warmest in August at 26 °C and coldest in February at 15 °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	9.1 °C	75 mm	43 %
February	9.5 °C	75 mm	51 %
March	12.2 °C	128 mm	59 %
April	16.1 °C	118 mm	62 %
May	19.8 °C	131 mm	68 %
June	22.6 °C	175 mm	80 %
July	25.8 °C	147 mm	73 %
August	27.4 °C	104 mm	62 %
September	25.1 °C	191 mm	65 %
October	20.6 °C	210 mm	61 %
November	16.1 °C	97 mm	54 %
December	11.6 °C	65 mm	45 %

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	9.1 °C	4.3 °C	6.7 °C	17.5 °C	-2.6 °C	0	0	0
February	9.5 °C	4.3 °C	7.0 °C	18.6 °C	-2.3 °C	0	0	1
March	12.2 °C	6.9 °C	9.7 °C	19.5 °C	0.9 °C	0	0	0
April	16.1 °C	11.5 °C	13.9 °C	21.8 °C	4.0 °C	0	0	0
May	19.8 °C	15.9 °C	17.9 °C	24.5 °C	8.2 °C	0	0	0
June	22.6 °C	19.4 °C	21.0 °C	27.7 °C	13.8 °C	2	0	0
July	25.8 °C	22.9 °C	24.3 °C	31.0 °C	17.4 °C	21	0	0
August	27.4 °C	24.3 °C	25.8 °C	32.7 °C	19.1 °C	29	1	0
September	25.1 °C	21.6 °C	23.3 °C	31.1 °C	14.4 °C	17	0	0
October	20.6 °C	16.7 °C	18.6 °C	27.5 °C	9.7 °C	1	0	0
November	16.1 °C	11.7 °C	14.0 °C	22.9 °C	3.2 °C	0	0	0
December	11.6 °C	6.9 °C	9.3 °C	22.7 °C	-0.3 °C	0	0	0

Rain, sun and wind month by month

Month	Rainfall	Wet days	Daylight	Cloud cover	Humidity	Wind	Sea temp
January	75 mm	7	10 h/day	43 %	62 %	26 km/h	16.3 °C
February	75 mm	9	11 h/day	51 %	63 %	27 km/h	15.2 °C
March	128 mm	12	12 h/day	59 %	68 %	29 km/h	15.5 °C
April	118 mm	11	13 h/day	62 %	73 %	29 km/h	16.7 °C
May	131 mm	11	14 h/day	68 %	79 %	26 km/h	18.9 °C
June	175 mm	14	15 h/day	80 %	85 %	24 km/h	21.3 °C
July	147 mm	12	14 h/day	73 %	88 %	24 km/h	23.7 °C
August	104 mm	11	14 h/day	62 %	85 %	23 km/h	25.9 °C
September	191 mm	13	12 h/day	65 %	81 %	24 km/h	25.3 °C
October	210 mm	12	11 h/day	61 %	75 %	24 km/h	23.1 °C
November	97 mm	9	10 h/day	54 %	71 %	24 km/h	20.8 °C
December	65 mm	7	9.8 h/day	45 %	64 %	25 km/h	18.4 °C

How Yokosuka 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
Yokosuka	27 °C	4.3 °C	1,517 mm	70
Yokohama · Japan	28 °C	2.4 °C	1,493 mm	75
Fujisawa · Japan	28 °C	3.1 °C	1,601 mm	72
Kawasaki · Japan	29 °C	1.6 °C	1,484 mm	87
Atsugi · Japan	28 °C	1.8 °C	1,863 mm	74
Machida · Japan	28 °C	0.4 °C	1,619 mm	75
Hadano · Japan	28 °C	1.2 °C	1,862 mm	82

Where Yokosuka ranks

Ranking	Position	Value
The coolest places in Asia in June	37th of 50	23 °C
Best beach destinations in Asia in August	50th of 50	84/100

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

QuestionsCommon questions about Yokosuka’s climate

When is the best time to visit Yokosuka?

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

How hot does Yokosuka get?

In August, the warmest month, daily highs average 27 °C. About 1 days a year pass 30 °C. The highest value in the 1991–2020 record is 33 °C.

How cold does it get in winter?

Nights average 4.3 °C in January, the coldest month. A normal year has 1 nights below freezing.

Which month is wettest in Yokosuka?

October, averaging 210 mm over 12 days with rain. The driest month is December with 65 mm. The year as a whole averages 1,517 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 Yokosuka 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: 35.284°, 139.667° (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.