May Weather in Hiroshima, Japan

Last updated: August 21, 2025

May in Hiroshima, Japan ushers in a delightful warmth, with maximum temperatures soaring to 30°C (86°F) and an inviting average temperature of 18°C (65°F). As spring transitions into summer, residents experience a refreshing minimum of 5°C (42°F) during cooler nights. The month brings an average of 121 mm (4.8 in) of rain over 9 days, contributing to a humble yet noticeable humidity level of 84%, which envelops the city in a lush, verdant atmosphere. This combination of warmth and moisture fosters a vibrant landscape, making May an ideal time to explore Hiroshima's rich culture and natural beauty.

May Temperature in Hiroshima

May in Hiroshima marks a delightful transition into warmer weather, showcasing a noticeable shift from the chill of previous months. With minimum temperatures rising to 5°C (42°F) and an average of 18°C (65°F), the city begins to embrace the warmth of spring. The maximum temperature climbs significantly to 30°C (86°F), inviting residents and visitors alike to enjoy outdoor activities under sunny skies. This month not only signifies the end of the cooler season but also heralds an increase in vibrant blooms and lush greenery, making May a perfect time to experience the natural beauty of Hiroshima. Overall, the temperature trend reflects a shift toward more comfortable and enjoyable conditions, ideal for exploring the city's historic sites and parks.

May Weather in Hiroshima: Daily Temperature Highs, Lows, and Averages

The chart illustrates May temperature patterns in Hiroshima, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Hiroshima, May typically has an average temperature of {2}°C ({3}°F), with highs reaching up to {4}°C ({5}°F) and lows dropping to around {6}°C ({7}°F).
JanFebMarAprMayJunJulAugSepOctNovDec394048566571788173635243
Data source: Temperature data for Hiroshima generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

May Precipitation in Hiroshima

In Hiroshima, the month of May sees a noteworthy balance in precipitation, with a total of 121 mm (4.8 in) accumulated over 9 days. This amount is slightly lower than the previous month's 128 mm (5.0 in), yet it maintains a similar rhythm, contributing to the lush landscapes typical of early spring. As the city transitions into the increasingly rainy summer months, June's precipitation dramatically rises to 177 mm (7.0 in), highlighting the shift toward more frequent and intense rainfall. May’s steady precipitation serves as a reminder of the region's vibrant hydrology, supporting both flora and fauna as they thrive in this temperate climate.

May Precipitation Trends in Hiroshima

The chart displays monthly precipitation patterns in Hiroshima, with values for each month alongside May’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how May’s conditions compare to those of other months. In Hiroshima, May typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec54671201281211773922572311643966
Data source: Precipitation data for May generated using information from the Copernicus Climate Change Service.
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May Humidity in Hiroshima

May in Hiroshima, Japan, ushers in a notable shift in humidity, peaking at 84%. This is a significant increase from April's 75%, marking the onset of a more oppressive moisture level as the region transitions into summer. The climb continues into June, where humidity rises to 88%, setting the stage for the sweltering July and August months that follow, characterized by their peak humidity levels of 95% and 93%, respectively. This trend highlights a clear trajectory: as spring blooms into summer, residents can expect increasingly humid conditions, making May a precursor to the heat and humidity that defines Hiroshima's summer months.

May Average Humidity in Hiroshima

This chart illustrates the average monthly humidity levels in Hiroshima, with May’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In May, average humidity in Hiroshima is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec76%72%69%75%84%88%95%93%84%79%76%75%
Data source: Humidity data for May generated using information from the Copernicus Climate Change Service.

May UV Index in Hiroshima

In May, the UV Index in Hiroshima reaches a striking 11, placing it in the extreme exposure category, much like April. This means that residents and visitors alike should be particularly vigilant, as the burn time is a mere 10 minutes! Interestingly, this trend of high UV levels continues into June and July. Compared to the milder months earlier in the year, such as January and February with their moderate UV Index of 4 and 5, May stands out as a crucial reminder to take sun safety seriously. For more detailed information on UV levels throughout the year, check out Hiroshima UV Index.

Maximum UV Index Levels in Hiroshima for May

The chart shows the monthly maximum UV Index (UVI) for Hiroshima in May, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In May, the maximum UV index in Hiroshima typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec458111111121210764
Data source: Hiroshima May UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

May Sunshine in Hiroshima

As May arrives in Hiroshima, it brings with it a spectacular surge in sunshine, with an impressive 303 hours of bright, sunny days. This month marks a peak in daylight hours, following a steady increase from the 184 hours recorded in January. The delightful progression continues through spring, with April showing a promising 282 hours. While June sees a slight dip to 291 hours, the trend of abundance in daylight resonates throughout the summer months, leading into the sun-drenched 308 hours of August. The pattern of increasing sunshine not only enhances the beauty of Hiroshima's landscapes but also uplifts the spirits of its residents, making May a truly joyful month to bask in the warmth of the sun.

Monthly Sunshine Duration in Hiroshima: May Highlighted

The May sunshine duration represents the total number of hours Hiroshima experiences direct sunlight during the month of May, excluding cloudy or obstructed periods. This chart compares the sunshine duration of May with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec184h227h266h282h303h291h281h308h260h254h237h220h
Data source: Hiroshima May Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Hiroshima During May

In Hiroshima, May marks a transitional phase in weather patterns, as the likelihood of sunny days dips to 30%. This decrease follows the relatively promising April, which boasts a 46% chance of sun, highlighting a notable trend where spring begins with brighter prospects. As the city transitions into the summer months, the chances of sunshine diminish further into June and July, hitting a low of 25%. Interestingly, this downturn contrasts sharply with the higher figures observed in the latter part of the year, such as October's 56%, suggesting that while May may be less consistent, it paves the way for the more variable weather that summer brings.

Percentage of Sunny Days in May in Hiroshima

The chart illustrates the percentage of sunny days in Hiroshima throughout the year, with May highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Hiroshima experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec38%48%37%46%30%25%23%25%28%56%50%50%
Data source: Hiroshima May chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Hiroshima in May

In Hiroshima, Japan, the transition of daylight duration throughout the year reveals a dynamic shift as the seasons change. Starting with 10 hours of daylight in both January and February, the days gradually lengthen, gaining an hour by March. As spring arrives, daylight peaks to 13 hours in April and May, inviting the blossoming beauty of nature. The longest days occur in the heart of summer, with 14 hours of sunlight in June and July. However, as August rolls in and autumn approaches, the daylight begins to wane, decreasing to 13 hours and gradually settling back to 10 hours by November. December brings the shortest days, wrapping up the yearly cycle with 9 hours of daylight, illustrating a captivating rhythm that enhances the vibrant seasonal changes in Hiroshima.

Average Daylight Hours in Hiroshima for May

The chart illustrates the variation in daylight duration in Hiroshima throughout the year, with May highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec10h 7m10h 55m11h 58m13h 2m13h 56m14h 24m14h 10m13h 23m12h 21m11h 17m10h 21m9h 53m
Data source: Hiroshima daylight hours, calculated by summing the hours between sunrise and sunset for each day.

May Winds in Hiroshima

In Hiroshima, May brings a gentle breath of wind, with an average speed of 2.6 m/s (6 mph), consistent with the calmer breezes felt in April and March. This trend of mild winds continues into the early summer months, signaling a transition as the city gears up for warmer days ahead. Interestingly, wind speeds dip in June and July, suggesting a serene atmosphere that envelops the city as it approaches the height of summer. Overall, May’s winds remain steady and soothing, providing a pleasant backdrop to the blossoming beauty of spring in this historic city.

Average May Wind Speed in Hiroshima

The chart displays monthly wind speed patterns in Hiroshima, with values for each month shown alongside May's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how May's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec2.83.02.62.62.6 m/s1.82.02.42.12.02.43.0
Data source: Hiroshima May wind data, generated using information from the Copernicus Climate Change Service.

How May Weather in Hiroshima Compares to Other Months

Weather in Hiroshima varies notably across the year, with each month offering distinct climate conditions. This page compares May’s weather to other months in Hiroshima, focusing on differences in temperature, rainfall, humidity, and UV levels.

May and January showcase a stark contrast in weather patterns. In May, temperatures typically range from a mild 5°C (42°F) at night to a warm 30°C (86°F) during the day, with an average of 18°C (65°F). This month also sees a fair amount of precipitation, totaling 121 mm (4.8 in) over approximately 9 days, and humidity levels are high at 84%. In comparison, January experiences much colder conditions, with temperatures dropping as low as -7°C (20°F), averaging around 4°C (39°F), and peaking at 14°C (58°F). Precipitation is significantly lower in January, at 54 mm (2.1 in) over the same number of wet days, and humidity is slightly lower at 76%. For more detailed information on January weather, visit Hiroshima weather in January.

May and February display contrasting weather patterns, significantly influenced by seasonal transitions. In May, temperatures range from a chilly 5°C (42°F) at night to a warm 30°C (86°F) during the day, with an average of 18°C (65°F). The month experiences higher precipitation, totaling 121 mm (4.8 in) over 9 days, accompanied by an elevated humidity level of 84%. In stark contrast, February is much cooler, with temperatures dipping as low as -7°C (19°F) and averaging at just 5°C (41°F), reaching a maximum of 20°C (69°F). It has lower precipitation of 67 mm (2.6 in) over the same number of days, and a relative humidity of 72%. Overall, May heralds the warmth of spring while February is characterized by winter’s lingering chill. For more details, you can check out Hiroshima weather in February.

In comparing the weather of May and March, it's evident that May is significantly warmer, with average temperatures reaching 18°C (65°F), compared to March's cooler average of 9°C (48°F). May showcases a wider temperature range, with maximums peaking at 30°C (86°F), whereas March peaks at a moderate 22°C (71°F). Both months experience similar levels of precipitation, with May receiving 121 mm (4.8 in) over 9 days and March slightly lower at 120 mm (4.7 in) over 12 days. Notably, May's humidity of 84% contributes to a more humid atmosphere than March's 69%. For a detailed look at March weather, visit Hiroshima weather in March.

In comparing the weather between April and May, we observe a noticeable shift in both temperature and humidity. In April, temperatures range from a minimum of -1°C (31°F) to a maximum of 26°C (79°F), with an average of 13°C (56°F), while May experiences milder conditions with minimums of 5°C (42°F) and maximums reaching 30°C (86°F), averaging at 18°C (65°F). Although April has slightly higher precipitation at 128 mm (5.0 in) compared to May’s 121 mm (4.8 in), both months have rainfall on about 9 days. Additionally, the relative humidity in May is higher at 84%, compared to April’s 75%, making May feel a bit more humid overall. For a detailed look at April's weather, you can check Hiroshima weather in April.

In comparing the weather of May and June, we see a noticeable warming trend. May experiences temperatures ranging from a minimum of 5°C (42°F) to a maximum of 30°C (86°F), with an average of 18°C (65°F). In contrast, June offers slightly higher temperatures, with a minimum of 11°C (52°F) and an average of 21°C (71°F), peaking at around 30°C (87°F). However, June also brings increased precipitation, totaling 177 mm (7.0 in) over 14 days, compared to May's 121 mm (4.8 in) over 9 days. Additionally, humidity levels rise from 84% in May to 88% in June, reflecting the transition to a more humid season. For more detailed information, check out Hiroshima weather in June.

May and July present contrasting weather patterns. In May, temperatures range from a cooler minimum of 5°C (42°F) to a moderate average of 18°C (65°F), peaking at 30°C (86°F). The month experiences 121 mm (4.8 in) of precipitation over 9 days, accompanied by high humidity at 84%. In contrast, July sees significantly warmer temperatures, with a minimum of 17°C (64°F), an average of 26°C (78°F), and a maximum reaching 35°C (96°F). However, it also experiences much higher rainfall at 391 mm (15.4 in) over 19 days, along with increased humidity at 95%. For more about the weather in this month, check Hiroshima weather in July.

May and August present contrasting weather characteristics. In May, temperatures range from a chilly 5°C (42°F) at night to a comfortable average of 18°C (65°F), with day temperatures peaking at 30°C (86°F). The month sees approximately 121 mm (4.8 in) of precipitation over about 9 days, accompanied by a relatively high humidity of 84%. In stark contrast, August is distinctly warmer, with nighttime lows of 17°C (63°F) and daytime averages soaring to 27°C (81°F), reaching maximum temperatures of 36°C (97°F). This month also experiences higher rainfall, totaling 257 mm (10.1 in) over 14 days, alongside a slight increase in humidity at 93%. For more detailed information, check out Hiroshima weather in August.

May and September present distinct weather patterns, reflecting the transition from spring to autumn. In May, temperatures range from a cool 5°C (42°F) at night to a warm average of 18°C (65°F) during the day, reaching a peak of 30°C (86°F). The month sees about 121 mm (4.8 in) of precipitation over approximately 9 days, maintaining a high humidity level of 84%. In contrast, September brings warmer temperatures, with nighttime lows starting at 12°C (54°F) and averaging 23°C (73°F), peaking at 33°C (92°F). However, rainfall increases significantly, totaling around 230 mm (9.1 in) over about 14 days, while humidity remains steady at 84%. For more detailed weather insights, visit Hiroshima weather in September.

In comparing the weather between May and October, both months exhibit mild temperatures, with May showcasing a higher average temperature of 18°C (65°F) compared to October's 17°C (63°F). The maximum temperatures in May can reach up to 30°C (86°F), while October's highs are slightly cooler at 28°C (84°F). Precipitation is more significant in October, with 164 mm (6.5 in) over 11 days, compared to May's 121 mm (4.8 in) across 9 days. Interestingly, while May experiences a higher humidity level at 84%, October's humidity is relatively lower at 79%. For more detailed information on October weather, you can visit Hiroshima weather in October.

May and November offer contrasting weather experiences. In May, temperatures range from a minimum of 5°C (42°F) to a maximum of 30°C (86°F), with an average of 18°C (65°F). This month sees significant rainfall, averaging 121 mm (4.8 in) over approximately 9 days, accompanied by high humidity at 84%. In contrast, November presents cooler conditions, with temperatures ranging from -1°C (31°F) to 23°C (75°F) and an average of 11°C (52°F). Precipitation is notably lower at 39 mm (1.5 in) over 5 days, and humidity stands at 76%. For a detailed look at November weather, check out Hiroshima weather in November.

May and December present quite contrasting weather conditions. In May, temperatures can range from a chilly 5°C (42°F) to a warm 30°C (86°F), with an average of around 18°C (65°F). The month experiences higher humidity at 84% and more precipitation, totaling 121 mm (4.8 in) over approximately 9 days. In contrast, December features cooler temperatures, ranging from a minimum of -2°C (28°F) to a maximum of 20°C (68°F), with a significantly lower average of 6°C (43°F). Precipitation drops to 66 mm (2.6 in) over about 10 days, accompanied by a humidity level of 75%. For more specific insights on December weather, you can refer to Hiroshima weather in December.

Compare Hiroshima's Climate with Cities Worldwide

Conclusion: What to Expect From May Weather in Hiroshima

As May rolls into Hiroshima, the weather begins to shift, offering a delightful prelude to summer. With temperatures rising to a pleasant average of 18°C and reaching peaks around 30°C, this month stands out as warmer compared to the cooler months of spring. However, the generous rainfall, amounting to 121 mm spread over 9 days, introduces a noticeable increase in humidity, which sits at a rather humid 84%. This creates a rich atmosphere, often leading to lush greenery throughout the city. If you're curious about how May fits into Hiroshima's overall climate, be sure to explore Hiroshima Climate for more insights!