Climate in Osaka (Japan)

The climate of Osaka, a Japanese city in the southern part of Honshu Island, is temperate humid, with quite mild winters and hot, moist, and rainy summers. Like the rest of Japan, the city is affected by the monsoon circulation: in winter, the northwest cold currents will prevail, while in summer, they will be replaced by hot and humid currents of tropical origin.
The town is located on the coast, in the Seto Inland Sea, an area relatively protected both from the summer monsoon and from typhoons.

In winter, there are fairly mild periods, with highs above 10 °C (50 °F), alternating with cold periods, with wind and rain, highs around 5/7 °C (41/45 °F) or less, and possible falls of sleet or snow. Snowfalls, however, are usually light, as are nocturnal frosts.

Summers in Osaka are particularly hot and humid, also for the heat island effect which is typical of big cities. There can be periods of good weather, with maximum temperatures around 35 °C (95 °F) or above, tropical nights and high humidity, but also periods of bad weather due to the summer monsoon. August is the hottest month, both because of the thermal inertia of the sea and because of the lower frequency of periods of bad weather.

Rainfall is quite abundant, in fact, it amounts to 1,300 millimeters (51 inches) per year. Winter is undoubtedly the driest season; the rainiest months are June and July, ie the first period of the rainy season (called Baiu). In August, there is a certain decrease in rain frequency: on average, among the summer months, it is the hottest as well as the driest and sunniest.

On the whole, the amount of sunshine is decent in winter, but it never becomes very good on average, however, there are two relative maxima, one in spring (April-May) and the other in August, after the Baiu rains, with 6.5/7 hours of sunshine per day.



The sea near Osaka is warm enough for swimming, with a temperature of 23 °C (73 °F) or more, from July to October, and it becomes pleasantly warm in August.

From June to October (but especially from August to early October), Osaka may be affected by typhoons, the tropical cyclones of Southeast Asia, though the area of the Seto Inland Sea is relatively sheltered (however, in September 1934, the city was hit by a typhoon that caused a lot of damage).

Best Time

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As regards to the climate, the best times to visit Osaka are spring and autumn, and in particular, from mid-April to mid-May and from late October to mid-November.
The cherry blossoming in Osaka occurs around April the 3rd: even though in some years it can get a little cold, with highs around 12 °C (54 °F), you can also take advantage of this period.
In summer, August is partly preferable to July, having more sunshine and less rainfall, but it is also true that it is hotter and there's a greater risk of typhoons.

Osaka - Climate data

In Osaka, the average temperature of the coldest month (January) is of 6.4 °C (43.4 °F), that of the warmest month (August) is of 29.8 °C (85.6 °F). Here are the average temperatures.
Precipitation amounts to 1340 millimeters (52.8 inches) per year: it is therefore quite abundant. It ranges from 45 mm (1.8 in) in the driest month (January) to 185 mm (7.3 in) in the wettest one (June). Here is the average precipitation.
The sea temperature ranges from 15.5 °C (60 °F) in February, March to
There are on average around 2050 sunshine hours per year. Here are the average hours of sunshine per day.

Osaka - Weather by month

Based on the period 1991-2020

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January, the coldest month of the year, is generally a quite cold month. The average temperature is of 6.4 °C (43 °F), with a minimum of 3 °C (37.4 °F) and a maximum of 9.7 °C (49.5 °F).
On the coldest nights of the month, the temperature usually drops to around -0.5 °C (30.5 °F). However, it dropped to -3.8 °C (25.2 °F) in January 1997.
On the warmest days of the month, the temperature usually reaches around 14.5 °C (58 °F). However, it reached 19.1 °C (66.4 °F) in January 2020.
Precipitation amounts to 45 mm (1.8 in), distributed over 6 days.
The day lasts on average 10 hours and 5 minutes.
There are on average 4.5 hours of sunshine per day. So, the sun shines 47% of the time.
The average humidity is 61%.
The average wind speed is 10 kph (6 mph).
The average sea temperature is of 16.5 °C (61.5 °F). Therefore, the sea is cold for swimming.

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February is generally a quite mild month. The average temperature is of 6.8 °C (44 °F), with a minimum of 3.2 °C (37.8 °F) and a maximum of 10.5 °C (50.9 °F).
On the coldest nights of the month, the temperature usually drops to around -0.5 °C (31 °F). However, it dropped to -2.9 °C (26.8 °F) in February 1999.
On the warmest days of the month, the temperature usually reaches around 17.5 °C (63 °F). However, it reached 23.4 °C (74.1 °F) in February 2010.
Precipitation amounts to 60 mm (2.4 in), distributed over 7 days.
The day lasts on average 11 hours and 0 minutes.
There are on average 5 hours of sunshine per day. So, the sun shines 46% of the time.
The average humidity is 60%.
The average wind speed is 10 kph (6 mph).
The average sea temperature is of 15.5 °C (60 °F). Therefore, the sea is cold for swimming.

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March is generally a mild month. The average temperature is of 10.1 °C (50 °F), with a minimum of 6 °C (42.8 °F) and a maximum of 14.2 °C (57.6 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 1.5 °C (34.5 °F). However, it dropped to 0.1 °C (32.2 °F) in March 2001.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 21.5 °C (70.5 °F). However, it reached 24.2 °C (75.6 °F) in March 1999.
Precipitation amounts to 105 mm (4.1 in), distributed over 10 days.
The day lasts on average 12 hours and 0 minutes.
There are on average 5.5 hours of sunshine per day. So, the sun shines 46% of the time.
The average humidity is 59%.
The average wind speed is 10 kph (6 mph).
The average sea temperature is of 15.5 °C (60 °F). Therefore, the sea is cold for swimming.

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April is generally a very mild month. The average temperature is of 15.4 °C (60 °F), with a minimum of 10.9 °C (51.6 °F) and a maximum of 19.9 °C (67.8 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 5 °C (40.5 °F). However, it dropped to 2.6 °C (36.7 °F) in April 1996.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 26.5 °C (79.5 °F). However, it reached 30.7 °C (87.3 °F) in April 2005.
Precipitation amounts to 100 mm (3.9 in), distributed over 10 days.
The day lasts on average 13 hours and 5 minutes.
There are on average 6.5 hours of sunshine per day. So, the sun shines 49% of the time.
The average humidity is 58%.
The average wind speed is 10 kph (6 mph).
The average sea temperature is of 17 °C (62 °F). Therefore, the sea is cold for swimming.

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May is generally a warm month. The average temperature is of 20.4 °C (69 °F), with a minimum of 16 °C (60.8 °F) and a maximum of 24.9 °C (76.8 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 11 °C (51.5 °F). However, it dropped to 7.6 °C (45.7 °F) in May 1991.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 30 °C (86 °F). However, it reached 32.7 °C (90.9 °F) in May 1998.
Precipitation amounts to 135 mm (5.3 in), distributed over 10 days.
The day lasts on average 14 hours and 0 minutes.
There are on average 6.5 hours of sunshine per day. So, the sun shines 47% of the time.
The average humidity is 61%.
The average wind speed is 9 kph (6 mph).
The average sea temperature is of 19.5 °C (67 °F). Therefore, the sea is very cool for swimming.

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June is generally a warm to hot month. The average temperature is of 24.2 °C (75 °F), with a minimum of 20.3 °C (68.5 °F) and a maximum of 28 °C (82.4 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 16 °C (61 °F). However, it dropped to 14.3 °C (57.7 °F) in June 1993.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 32.5 °C (91 °F). However, it reached 36.1 °C (97 °F) in June 2013.
Precipitation amounts to 185 mm (7.3 in), distributed over 12 days.
The day lasts on average 14 hours and 25 minutes. So the days are long. June 21, the summer solstice, is the longest day of the year in the Northern Hemisphere.
There are on average 5 hours of sunshine per day. So, the sun shines 36% of the time.
The average humidity is 68%.
The average wind speed is 9 kph (6 mph).
The average sea temperature is of 22.5 °C (72.5 °F). Therefore, the sea can be considered barely acceptable for swimming.

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July is generally a very hot month. The average temperature is of 28.2 °C (83 °F), with a minimum of 24.6 °C (76.3 °F) and a maximum of 31.8 °C (89.2 °F).
On the coldest nights of the month, the temperature usually drops to around 20.5 °C (69 °F). However, it dropped to 18.1 °C (64.6 °F) in July 1992.
On the warmest days of the month, the temperature usually reaches around 36 °C (96.5 °F). However, it reached 38 °C (100.4 °F) in July 1994.
Precipitation amounts to 175 mm (6.9 in), distributed over 11 days.
The day lasts on average 14 hours and 10 minutes. So the days are long.
There are on average 6 hours of sunshine per day. So, the sun shines 42% of the time.
The average humidity is 70%.
The average wind speed is 9 kph (6 mph).
The average sea temperature is of 25.5 °C (78.5 °F). Therefore, the sea is warm enough for swimming.

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August, the hottest month of the year, is generally a very hot month. The average temperature is of 29.8 °C (86 °F), with a minimum of 25.8 °C (78.4 °F) and a maximum of 33.7 °C (92.7 °F).
On the coldest nights of the month, the temperature usually drops to around 22 °C (71.5 °F). However, it dropped to 19.9 °C (67.8 °F) in August 2018.
On the warmest days of the month, the temperature usually reaches around 37 °C (98.5 °F). However, it reached 39.1 °C (102.4 °F) in August 1994.
Precipitation amounts to 115 mm (4.5 in), distributed over 8 days.
The day lasts on average 13 hours and 25 minutes.
There are on average 7 hours of sunshine per day. So, the sun shines 53% of the time.
The average humidity is 66%.
The average wind speed is 9 kph (6 mph).
The average sea temperature is of 27.5 °C (82 °F). Therefore, the sea is pleasantly warm and allows long swims.

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September is generally a warm to hot month. The average temperature is of 25.7 °C (78 °F), with a minimum of 21.9 °C (71.4 °F) and a maximum of 29.5 °C (85.1 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 17 °C (62 °F). However, it dropped to 13.6 °C (56.5 °F) in September 1992.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 34 °C (93.5 °F). However, it reached 36.2 °C (97.2 °F) in September 2010.
Precipitation amounts to 155 mm (6.1 in), distributed over 11 days.
The day lasts on average 12 hours and 25 minutes.
There are on average 5.5 hours of sunshine per day. So, the sun shines 43% of the time.
The average humidity is 67%.
The average wind speed is 8 kph (5 mph).
The average sea temperature is of 26.5 °C (79.5 °F). Therefore, the sea is pleasantly warm and allows long swims.

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October is generally a warm month. The average temperature is of 19.8 °C (68 °F), with a minimum of 16 °C (60.8 °F) and a maximum of 23.7 °C (74.7 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 10.5 °C (50.5 °F). However, it dropped to 7.5 °C (45.5 °F) in October 1997.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 29.5 °C (85 °F). However, it reached 33.1 °C (91.6 °F) in October 2019.
Precipitation amounts to 135 mm (5.3 in), distributed over 9 days.
The day lasts on average 11 hours and 20 minutes.
There are on average 5.5 hours of sunshine per day. So, the sun shines 47% of the time.
The average humidity is 65%.
The average wind speed is 8 kph (5 mph).
The average sea temperature is of 23.5 °C (74.5 °F). Therefore, the sea can be considered barely acceptable for swimming.

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November is generally a mild month. The average temperature is of 14 °C (57 °F), with a minimum of 10.2 °C (50.4 °F) and a maximum of 17.8 °C (64 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 5 °C (41 °F). However, it dropped to 1.9 °C (35.4 °F) in November 2008.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 23.5 °C (74 °F). However, it reached 26.6 °C (79.9 °F) in November 2020.
Precipitation amounts to 75 mm (3 in), distributed over 7 days.
The day lasts on average 10 hours and 20 minutes.
There are on average 5 hours of sunshine per day. So, the sun shines 49% of the time.
The average humidity is 64%.
The average wind speed is 8 kph (5 mph).
The average sea temperature is of 21.5 °C (70.5 °F). Therefore, the sea is cool for swimming.

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December is generally a mild month. The average temperature is of 8.8 °C (48 °F), with a minimum of 5.3 °C (41.5 °F) and a maximum of 12.3 °C (54.1 °F).
On the coldest nights of the month, the temperature usually drops to around 1 °C (34 °F). However, it dropped to -0.8 °C (30.6 °F) in December 2005.
On the warmest days of the month, the temperature usually reaches around 18 °C (64 °F). However, it reached 24.5 °C (76.1 °F) in December 2018.
Precipitation amounts to 55 mm (2.2 in), distributed over 7 days.
The day lasts on average 9 hours and 55 minutes. December 21, the winter solstice, is the shortest day of the year in the Northern Hemisphere.
There are on average 5 hours of sunshine per day. So, the sun shines 49% of the time.
The average humidity is 62%.
The average wind speed is 9 kph (6 mph).
The average sea temperature is of 18.5 °C (65.5 °F). Therefore, the sea is very cool for swimming.