The climate of Hiroshima, a Japanese city in the southwestern part of Honshu Island, in the region called Chugoku, is
, with quite mild winters and muggy, rainy summers. Like the rest of Japan, the city is affected by the
: in winter, the northwest cold currents prevail, while in summer, they are replaced by hot and humid currents of tropical origin.
The town is located on the coast, in the Seto Inland Sea, a short distance from Shikoku and Kyushu islands.
, 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 generally light, as are nocturnal frosts.
are hot and humid; there can be periods of good weather, with maximum temperatures around 35 °C (95 °F), 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.
It should be noted that the temperatures recorded at the airport, which is located in a green zone, about 40 kilometers (25 miles) east of the city, and 330 meters (1,080 feet) above sea level, are much lower than those recorded in the city: for example, in January 2016, the temperature dropped to -8 °C (18 °F) at the airport and to -4 °C (25 °F) in the city.
is abundant, in fact, it amounts to 1,570 millimeters (62 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
). 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.
in Hiroshima is not very good, however, there are two relative maxima, one in spring (April-May) and the other in August, after the Baiu rains, both with 6.5/7 hours of sunshine per day.
in Hiroshima 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), Hiroshima can be affected by
, the tropical cyclones of Southeast Asia, though this area, in the Seto Inland Sea, is relatively protected (however, in September 1945, the city was hit by a typhoon that caused a lot of damage).
As regards to the climate, the best times to visit Hiroshima are spring and autumn, and in particular, from mid-April to mid-May and from late October to mid-November.
in Hiroshima reaches its peak around April 2-3. About a week passes between the beginning and the peak of the flowering. The blooming date can vary by a few days, or even a week, earlier or later, depending on the year. 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.
. Here are the average temperatures.
January, the coldest month of the year, is generally a quite cold month. The average temperature is of
6 °C, with a minimum of
2 °C and a maximum of
9.9 °C.
On the coldest nights of the month, the temperature usually drops to around
-2 °C. However, it dropped to
-4.6 °C in January 2011.
On the warmest days of the month, the temperature usually reaches around
14.5 °C. However, it reached
17.5 °C in January 1997.
Precipitation amounts to
45 mm, distributed over 7 days.
The day lasts on average 10 hours and 10 minutes.
There are on average 4.5 hours of sunshine per day. So, the sun shines 44% of the time.
The average humidity is 59%.
The average wind speed is of
10.7 kph.
The average sea temperature is of
16.1 °C. Therefore, the sea is cold for swimming.
February is generally a quite mild month. The average temperature is of
6.6 °C, with a minimum of
2.4 °C and a maximum of
10.9 °C.
On the coldest nights of the month, the temperature usually drops to around
-1.5 °C. However, it dropped to
-4.3 °C in February 2018.
On the warmest days of the month, the temperature usually reaches around
17 °C. However, it reached
21.5 °C in February 2009.
Precipitation amounts to
65 mm, distributed over 8 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 45% of the time.
The average humidity is 58%.
The average wind speed is of
10.8 kph.
The average sea temperature is of
14.9 °C. Therefore, the sea is cold for swimming.
March is generally a mild month. The average temperature is of
9.8 °C, with a minimum of
5.1 °C and a maximum of
14.5 °C.
On the coldest nights of the month, the temperature usually drops to around
0 °C. However, it dropped to
-1.8 °C in March 2001.
On the warmest days of the month, the temperature usually reaches around
21 °C. However, it reached
22.6 °C in March 2010.
Precipitation amounts to
120 mm, distributed over 11 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 47% of the time.
The average humidity is 57%.
The average wind speed is of
11.8 kph.
The average sea temperature is of
14.8 °C. Therefore, the sea is cold for swimming.
April is generally a very mild month. The average temperature is of
15 °C, with a minimum of
10.1 °C and a maximum of
19.8 °C.
On the coldest nights of the month, the temperature usually drops to around
3.5 °C. However, it dropped to
1 °C in April 1993.
On the warmest days of the month, the temperature usually reaches around
25.5 °C. However, it reached
29 °C in April 2004.
Precipitation amounts to
140 mm, 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 of
11.6 kph.
The average sea temperature is of
15.9 °C. Therefore, the sea is cold for swimming.
May is generally a warm month. The average temperature is of
19.8 °C, with a minimum of
15.1 °C and a maximum of
24.4 °C.
On the coldest nights of the month, the temperature usually drops to around
9.5 °C. However, it dropped to
6 °C in May 1991.
On the warmest days of the month, the temperature usually reaches around
29.5 °C. However, it reached
31.5 °C in May 1998.
Precipitation amounts to
170 mm, distributed over 10 days.
The day lasts on average 14 hours and 0 minutes.
There are on average 7 hours of sunshine per day. So, the sun shines 49% of the time.
The average humidity is 62%.
The average wind speed is of
11.2 kph.
The average sea temperature is of
18.3 °C. Therefore, the sea is very cool for swimming.
June is generally a warm to hot, muggy month. The average temperature is of
23.5 °C, with a minimum of
19.8 °C and a maximum of
27.2 °C.
On the coldest nights of the month, the temperature usually drops to around
15.5 °C. However, it dropped to
13 °C in June 2008.
On the warmest days of the month, the temperature usually reaches around
31.5 °C. However, it reached
33.6 °C in June 2011.
Precipitation amounts to
225 mm, 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 71%. Hence, the air is normally humid.
The average wind speed is of
11.1 kph.
The average sea temperature is of
21.5 °C. Therefore, the sea is cool for swimming.
July is generally a warm to hot, muggy month. The average temperature is of
27.5 °C, with a minimum of
24.1 °C and a maximum of
30.9 °C.
On the coldest nights of the month, the temperature usually drops to around
20.5 °C. However, it dropped to
16.9 °C in July 1992.
On the warmest days of the month, the temperature usually reaches around
35 °C. However, it reached
38.7 °C in July 1994.
Precipitation amounts to
280 mm, distributed over 12 days.
The day lasts on average 14 hours and 10 minutes. So the days are long.
There are on average 5.5 hours of sunshine per day. So, the sun shines 39% of the time.
The average humidity is 73%. Hence, the air is normally humid.
The average wind speed is of
12.1 kph.
The average sea temperature is of
24.8 °C. Therefore, the sea is warm enough for swimming.
August, the hottest month of the year, is generally a very hot month. The average temperature is of
29 °C, with a minimum of
25.1 °C and a maximum of
32.8 °C.
On the coldest nights of the month, the temperature usually drops to around
21 °C. However, it dropped to
18.7 °C in August 2002.
On the warmest days of the month, the temperature usually reaches around
36 °C. However, it reached
37.9 °C in August 2001.
Precipitation amounts to
130 mm, distributed over 9 days.
The day lasts on average 13 hours and 25 minutes.
There are on average 6.5 hours of sunshine per day. So, the sun shines 50% of the time.
The average humidity is 69%.
The average wind speed is of
12.4 kph.
The average sea temperature is of
27.1 °C. Therefore, the sea is pleasantly warm and allows long swims.
September is generally a warm to hot month. The average temperature is of
25.1 °C, with a minimum of
21.1 °C and a maximum of
29.1 °C.
On the coldest nights of the month, the temperature usually drops to around
16 °C. However, it dropped to
12.8 °C in September 1992.
On the warmest days of the month, the temperature usually reaches around
33.5 °C. However, it reached
36.9 °C in September 2007.
Precipitation amounts to
165 mm, distributed over 10 days.
The day lasts on average 12 hours and 20 minutes.
There are on average 5.5 hours of sunshine per day. So, the sun shines 45% of the time.
The average humidity is 67%.
The average wind speed is of
12.3 kph.
The average sea temperature is of
25.9 °C. Therefore, the sea is warm enough for swimming.
October is generally a warm month. The average temperature is of
19.3 °C, with a minimum of
14.9 °C and a maximum of
23.7 °C.
On the coldest nights of the month, the temperature usually drops to around
9 °C. However, it dropped to
6 °C in October 2002.
On the warmest days of the month, the temperature usually reaches around
29 °C. However, it reached
31.4 °C in October 2019.
Precipitation amounts to
110 mm, distributed over 7 days.
The day lasts on average 11 hours and 20 minutes.
There are on average 6 hours of sunshine per day. So, the sun shines 51% of the time.
The average humidity is 62%.
The average wind speed is of
11.6 kph.
The average sea temperature is of
23.3 °C. Therefore, the sea can be considered barely acceptable for swimming.
November is generally a mild month. The average temperature is of
13.3 °C, with a minimum of
8.9 °C and a maximum of
17.7 °C.
On the coldest nights of the month, the temperature usually drops to around
3.5 °C. However, it dropped to
0.2 °C in November 2008.
On the warmest days of the month, the temperature usually reaches around
23 °C. However, it reached
25.6 °C in November 2020.
Precipitation amounts to
70 mm, distributed over 7 days.
The day lasts on average 10 hours and 25 minutes.
There are on average 5 hours of sunshine per day. So, the sun shines 49% of the time.
The average humidity is 61%.
The average wind speed is of
10.7 kph.
The average sea temperature is of
20.9 °C. Therefore, the sea is cool for swimming.
December is generally a quite mild month. The average temperature is of
8 °C, with a minimum of
4 °C and a maximum of
12.1 °C.
On the coldest nights of the month, the temperature usually drops to around
0 °C. However, it dropped to
-3.6 °C in December 2005.
On the warmest days of the month, the temperature usually reaches around
17.5 °C. However, it reached
20.9 °C in December 1994.
Precipitation amounts to
55 mm, distributed over 8 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 4.5 hours of sunshine per day. So, the sun shines 46% of the time.
The average humidity is 61%.
The average wind speed is of
10.5 kph.
The average sea temperature is of
18.3 °C. Therefore, the sea is very cool for swimming.