Hadano climate

Name: Hadano
Address: JP

Hadano is warmest in August, with average highs of 28 °C, and coldest in January, when nights average 1.2 °C. September is the wettest month (235 mm) and December the driest (76 mm). Figures are 1991–2020 climate normals.

Across a full year Hadano averages 1,862 mm of rain, 82 days above 25 °C and 20 days below freezing.

Japan · population 163,787 · 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 1.2 °C
Driest month December 76 mm
Wettest month September 235 mm
Least cloud January 43 % cloud
Hottest on record August 34 °C
Coldest on record February -13 °C
Warmest sea August 26 °C

What to expectHadano through the year

Hadano has a clear annual cycle: average daily highs run from 8.3 °C in January to 28 °C in August, a swing of 21 °C in mean temperature across the year.

Counted across a normal year, 82 days a year reach 25 °C, 14 of them reach 30 °C, 20 nights drop below freezing. The warmest reading in the 1991–2020 record is 34 °C, in August.

Rain is strongly seasonal. September averages 235 mm against 76 mm in December — 3.1 times as much. Planning around the dry months matters more here than planning around temperature.

The sea off Hadano 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	8.3 °C	84 mm	43 %
February	8.9 °C	90 mm	51 %
March	12.1 °C	153 mm	60 %
April	16.8 °C	149 mm	64 %
May	20.9 °C	162 mm	71 %
June	23.7 °C	213 mm	83 %
July	27.4 °C	206 mm	76 %
August	28.5 °C	163 mm	67 %
September	25.4 °C	235 mm	70 %
October	20.4 °C	225 mm	64 %
November	15.6 °C	108 mm	54 %
December	10.8 °C	76 mm	44 %

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	8.3 °C	1.2 °C	4.5 °C	18.1 °C	-10.5 °C	0	0	8
February	8.9 °C	1.6 °C	5.0 °C	21.0 °C	-12.7 °C	0	0	8
March	12.1 °C	4.7 °C	8.2 °C	21.9 °C	-6.0 °C	0	0	2
April	16.8 °C	9.5 °C	13.0 °C	26.2 °C	-1.2 °C	0	0	0
May	20.9 °C	14.3 °C	17.5 °C	27.8 °C	5.6 °C	2	0	0
June	23.7 °C	18.4 °C	20.9 °C	32.0 °C	11.6 °C	9	0	0
July	27.4 °C	22.4 °C	24.7 °C	33.5 °C	16.9 °C	25	5	0
August	28.5 °C	23.3 °C	25.7 °C	33.9 °C	16.3 °C	29	8	0
September	25.4 °C	20.3 °C	22.6 °C	32.7 °C	12.3 °C	16	1	0
October	20.4 °C	15.0 °C	17.5 °C	29.2 °C	6.6 °C	2	0	0
November	15.6 °C	9.4 °C	12.3 °C	23.4 °C	-0.9 °C	0	0	0
December	10.8 °C	4.2 °C	7.2 °C	21.4 °C	-6.3 °C	0	0	2

Rain, sun and wind month by month

Month	Rainfall	Wet days	Daylight	Cloud cover	Humidity	Wind	Sea temp
January	84 mm	8	10 h/day	43 %	69 %	12 km/h	16.3 °C
February	90 mm	10	11 h/day	51 %	70 %	13 km/h	15.3 °C
March	153 mm	15	12 h/day	60 %	74 %	15 km/h	15.6 °C
April	149 mm	14	13 h/day	64 %	77 %	16 km/h	16.8 °C
May	162 mm	13	14 h/day	71 %	81 %	14 km/h	18.9 °C
June	213 mm	17	15 h/day	83 %	86 %	13 km/h	21.3 °C
July	206 mm	16	14 h/day	76 %	87 %	12 km/h	23.9 °C
August	163 mm	15	14 h/day	67 %	86 %	12 km/h	26.1 °C
September	235 mm	15	12 h/day	70 %	84 %	13 km/h	25.3 °C
October	225 mm	13	11 h/day	64 %	80 %	12 km/h	23.0 °C
November	108 mm	10	10 h/day	54 %	77 %	11 km/h	20.8 °C
December	76 mm	8	9.8 h/day	44 %	72 %	12 km/h	18.4 °C

How Hadano 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
Hadano	28 °C	1.2 °C	1,862 mm	82
Odawara · Japan	28 °C	2.5 °C	2,137 mm	71
Atsugi · Japan	28 °C	1.8 °C	1,863 mm	74
Fujisawa · Japan	28 °C	3.1 °C	1,601 mm	72
Aihara · Japan	28 °C	-1.5 °C	1,881 mm	80
Machida · Japan	28 °C	0.4 °C	1,619 mm	75
Hachiōji · Japan	29 °C	-1.9 °C	1,901 mm	85

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

QuestionsCommon questions about Hadano’s climate

When is the best time to visit Hadano?

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 Hadano get?

In August, the warmest month, daily highs average 28 °C. About 14 days a year pass 30 °C. The highest value in the 1991–2020 record is 34 °C.

How cold does it get in winter?

Nights average 1.2 °C in January, the coldest month. A normal year has 20 nights below freezing.

Which month is wettest in Hadano?

September, averaging 235 mm over 15 days with rain. The driest month is December with 76 mm. The year as a whole averages 1,862 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 Hadano 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: 35.371°, 139.224° (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.