July weather forecast
Hiroshima, Japan

July in Hiroshima brings the year's highest temperature, soaring to 30.8°C (87.4°F), offering a hot, summer environment during the peak travel season. As the rainfall continues at a high pace, the high humidity intensifies the perceived heat. Despite the monsoon-like conditions, Hiroshima endures significant sunshine hours, creating a steamy atmosphere. Nights also stay warm, offering little respite from the day's heat. The sea temperature begins to climb, making it an ideal time for water sports and beach activities.

Temperature

A soft shift in the average high-temperature is noticeable in July, transitioning from a moderately hot 27.2°C (81°F) in June to a hot 30.8°C (87.4°F). The temperature in Hiroshima dips to an average of 23.8°C (74.8°F) during July nights.

Heat index

For July, the heat index is appraised at a torrid 38°C (100.4°F). Undertake additional safety actions, risk of heat cramps and heat exhaustion is significant. Persistent activity may induce heatstroke.
Heat index specifics point out values are for conditions of shade and a slight breeze. The direct sun can potentially cause the heat index to increase by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'felt air temperature', is a metric representing the sensation of warmth when air temperature and moisture come together. Additional elements encompassing metabolic differences, the degree of physical activity, and attire can impact the individual's perception of temperature. Keep in mind that direct sunshine exposure can amplify the weather's effects, possibly increasing the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are highly critical to babies and toddlers. Younglings frequently fail to recognize the requirement to rest and rehydrate. Thirst emerges late in dehydration - it is imperative to keep hydration levels high, particularly during extended physical exertions.
To achieve cooling, the human body employs perspiration, relying on the subsequent evaporation of sweat. In situations of high air temperature combined with high humidity (significant heat index), the body's ability to perspire is reduced, heightening the sense of warmth. Excessive heat that's not properly managed leads to increased body temperatures and resultant health issues.

Humidity

The most humid month in Hiroshima is July, with an average relative humidity of 74%.

Rainfall

The month with the most rainfall in Hiroshima is July, when the rain falls for 17 days and typically aggregates up to 259mm (10.2") of precipitation.

Snowfall

April through November are months without snowfall in Hiroshima.

Sea temperature

In Hiroshima, the average seawater temperature in July is 24.6°C (76.3°F).
Note: Imagine a swim in 24.6°C (76.3°F) waters. How you'd feel depends on your cold sensitivity, the sun's rays, the caress of the wind, and the warmth enveloping you. Comparatively, Olympic swimmers train in waters between 25°C (77°F) and 28°C (82.4°F).

Daylight

In Hiroshima, the average length of the day in July is 14h and 12min.
On the first day of the month, sunrise is at 05:01 and sunset at 19:26. On the last day of July, in Hiroshima, sunrise is at 05:20 and sunset at 19:12 JST.

Sunshine

In Hiroshima, the average sunshine in July is 5.8h.

UV index

July is the month with the highest UV index in Hiroshima, with an average maximum UV index of 11. A UV Index estimate of 11, and higher, represents an excessive health risk from unprotected exposure to Sun's UV rays for ordinary individuals.
Note: The daily high UV index of 11 during July translates into the following recommendations:
Carry out all crucial safety measures, unprotected skin may burn instantly. From 10 a.m. to 4 p.m., when UV radiation is at its strongest, limit direct exposure to the Sun and note that shade structures may not provide full sun protection. Enhance your sun protection with tightly woven, yet airy clothing. Even if the day is cloudy, sunscreen with SPF of at least 30 should be applied generously and reapplied often, particularly after swimming or outdoor exercise. Stay vigilant! UV rays get a boost in intensity due to sand and water reflections.