Osaka climate

Name: Osaka
Address: JP

Osaka is warmest in August, with average highs of 32 °C, and coldest in January, when nights average 1.2 °C. June is the wettest month (197 mm) and January the driest (58 mm). Figures are 1991–2020 climate normals.

Across a full year Osaka averages 1,455 mm of rain, 118 days above 25 °C and 21 days below freezing.

Japan · population 2,753,862 · 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 32 °C
Coldest month January 1.2 °C
Driest month January 58 mm
Wettest month June 197 mm
Least cloud December 48 % cloud
Hottest on record August 39 °C
Coldest on record February -6.4 °C
Warmest sea August 27 °C

What to expectOsaka through the year

Osaka has a clear annual cycle: average daily highs run from 8.3 °C in January to 32 °C in August, a swing of 23 °C in mean temperature across the year.

Counted across a normal year, 118 days a year reach 25 °C, 46 of them reach 30 °C, 21 nights drop below freezing. The warmest reading in the 1991–2020 record is 39 °C, in August.

Rain is strongly seasonal. June averages 197 mm against 58 mm in January — 3.4 times as much. Planning around the dry months matters more here than planning around temperature.

The sea off Osaka is warmest in August at 27 °C and coldest in February at 13 °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	58 mm	52 %
February	9.2 °C	67 mm	56 %
March	12.8 °C	110 mm	58 %
April	18.1 °C	121 mm	59 %
May	23.0 °C	141 mm	66 %
June	26.3 °C	197 mm	78 %
July	29.7 °C	187 mm	71 %
August	31.6 °C	108 mm	58 %
September	27.7 °C	168 mm	61 %
October	21.8 °C	156 mm	53 %
November	16.1 °C	79 mm	50 %
December	10.7 °C	63 mm	48 %

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	16.9 °C	-4.3 °C	0	0	9
February	9.2 °C	1.5 °C	5.0 °C	20.2 °C	-6.4 °C	0	0	8
March	12.8 °C	4.3 °C	8.3 °C	21.1 °C	-1.9 °C	0	0	2
April	18.1 °C	9.5 °C	13.6 °C	28.2 °C	0.4 °C	0	0	0
May	23.0 °C	14.6 °C	18.5 °C	29.6 °C	6.1 °C	7	0	0
June	26.3 °C	19.2 °C	22.4 °C	34.8 °C	11.5 °C	21	1	0
July	29.7 °C	23.4 °C	26.3 °C	37.3 °C	15.9 °C	30	15	0
August	31.6 °C	24.5 °C	27.6 °C	38.9 °C	17.8 °C	31	23	0
September	27.7 °C	20.6 °C	23.7 °C	36.0 °C	11.8 °C	24	7	0
October	21.8 °C	14.5 °C	17.8 °C	30.6 °C	5.3 °C	4	0	0
November	16.1 °C	8.6 °C	12.1 °C	26.1 °C	1.4 °C	0	0	0
December	10.7 °C	3.5 °C	6.8 °C	22.8 °C	-2.1 °C	0	0	2

Rain, sun and wind month by month

Month	Rainfall	Wet days	Daylight	Cloud cover	Humidity	Wind	Sea temp
January	58 mm	6	10 h/day	52 %	73 %	17 km/h	14.3 °C
February	67 mm	7	11 h/day	56 %	72 %	17 km/h	13.0 °C
March	110 mm	11	12 h/day	58 %	71 %	18 km/h	13.3 °C
April	121 mm	10	13 h/day	59 %	71 %	17 km/h	15.1 °C
May	141 mm	10	14 h/day	66 %	73 %	16 km/h	17.8 °C
June	197 mm	13	14 h/day	78 %	77 %	15 km/h	21.2 °C
July	187 mm	14	14 h/day	71 %	80 %	15 km/h	24.7 °C
August	108 mm	11	13 h/day	58 %	75 %	15 km/h	26.8 °C
September	168 mm	12	12 h/day	61 %	76 %	15 km/h	25.8 °C
October	156 mm	10	11 h/day	53 %	76 %	14 km/h	22.9 °C
November	79 mm	7	10 h/day	50 %	76 %	14 km/h	19.5 °C
December	63 mm	7	9.8 h/day	48 %	75 %	16 km/h	16.6 °C

How Osaka 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
Osaka	32 °C	1.2 °C	1,455 mm	118
Sakai · Japan	31 °C	1.3 °C	1,449 mm	113
Nishinomiya · Japan	31 °C	1.5 °C	1,561 mm	119
Hirakata · Japan	31 °C	0.6 °C	1,380 mm	116
Izumi · Japan	31 °C	0.6 °C	1,456 mm	107

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

QuestionsCommon questions about Osaka’s climate

When is the best time to visit Osaka?

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 January the driest. The month-by-month table above has the full picture.

How hot does Osaka get?

In August, the warmest month, daily highs average 32 °C. About 46 days a year pass 30 °C. The highest value in the 1991–2020 record is 39 °C.

How cold does it get in winter?

Nights average 1.2 °C in January, the coldest month. A normal year has 21 nights below freezing.

Which month is wettest in Osaka?

June, averaging 197 mm over 13 days with rain. The driest month is January with 58 mm. The year as a whole averages 1,455 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 Osaka 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: 34.694°, 135.501° (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.