Hiroshima in August: weather, what to wear and what's on

Hiroshima weather in August

Averages for 1991–2020 at the JMA's Hiroshima station (4 m above sea level).

High

32.8°C (91°F)

Low

25.1°C (77°F)

Precipitation

131.4 mm

Wet days

7.6 days

Sunshine

207 hours

Highs are 1.9°C above July and 3.7°C above September.

That is 11.7°C above Hiroshima's yearly average high of 21.1°C.

Of our 14 places with temperature records, Hiroshima is the 5th warmest in August: 0.4°C cooler than Nagoya and 0.3°C warmer than Fukuoka.

August is Hiroshima's 6th wettest month (131.4 mm).

Of our 15 places, Hiroshima has the 4th lowest precipitation in August: 8.1 mm less than Nagoya and 3.5 mm more than Nara.

Rain of 1 mm or more falls on 7.6 days, and 10 mm or more on 3.5 days.

Rain of 30 mm or more in one day falls on 1.5 days, and 50 mm or more on 0.6 days.

26.7 days reach 30°C or more, and 5.9 reach 35°C or more.

On 18.2 nights the low stays at 25°C or above.

The sun is out for 40% or more of the possible hours on 19.7 days, and 2.3 days have under 0.1 hours of sunshine.

By the JMA's cloud records, 1.8 days are clear and 11.2 are overcast.

On 15 August 2027 the sun rises at 5:31 and sets at 18:59 in Hiroshima, giving 13 hours 28 minutes of daylight (NAOJ).

Average temperature

28.5°C (83°F)

Humidity

69%

Days of 25°C or more

30.9 days

Early, mid and late August

By the last ten days of August the average high in Hiroshima is 1.4°C lower than in the first ten.

By ten-day totals, 11–20 August is the wettest (47.4 mm) and 1–10 August the driest (39.2 mm).

What to wear in Hiroshima in August

Hot: highs around 32.8°C

• Short sleeves and light, breathable clothes. A light layer for cold air-conditioning on trains and in shops.
• Heat: 26.7 days reach 30°C or more. A hat, water and sunscreen.
• Warm nights: on 18.2 nights the temperature stays at 25°C or above.
• A folding umbrella: rain falls on 7.6 days.

Pack

• Folding umbrella
• Hat, sunscreen and a water bottle
• A light layer for air-conditioning

• Our clothing rules

Rainy season and typhoons

In an average August, 0.8 typhoons come within 300 km of the Chugoku region; across Japan, 3.3 come within 300 km and 0.9 make landfall (JMA, 1991–2020).

August records in Hiroshima

The extremes the JMA has measured in August at its Hiroshima station.

Hottest August day

38.7°C (102°F) on 16 August 2024 (records since 1879)

Coldest August night

13.7°C (57°F) on 28 August 1884 (records since 1879)

Wettest August day

205.5 mm on 14 August 2021 (records since 1879)

Holidays and crowds in August

National holidays in August 2027:

• Wed 11 August — Mountain Day

In August 2025, hotels and inns across Hiroshima Prefecture were 67.8% full on average (3rd busiest of 12 months). Foreign guests spent 160,820 nights there that month (Japan Tourism Agency). That compares with 63.0% in July and 66.5% in September.

• Japan in August: visitor numbers and busy travel days
• Holidays in August
• Obon

What's on in Hiroshima in August

Hiroshima before and after August

• Hiroshima in July
• Hiroshima in September
• All 12 months in Hiroshima

Other places in August

• All 15 places in August

Related items

• Hiroshima by month
• Japan in August
• Hiroshima in July
• Hiroshima in September