Hiroshima, Japan – Climate and Average Weather Year Round: Key Facts and Insights

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Hiroshima, Japan, is home to a unique climate that varies significantly throughout the year. Located in Asia, this city’s weather conditions are influenced by both its proximity to the ocean and its geographical setting.

The hottest month in Hiroshima is August, with an average high of 88°F and a low of 75°F. This makes it a popular time for tourists who enjoy warm weather.

Winter in Hiroshima is much cooler, with the coldest month being January.

During this time, temperatures average a low of 34°F and a high of 47°F.

Visitors from Tokyo and other parts of Japan, as well as from around the world, often find Hiroshima a fascinating study in contrasts when it comes to weather averages and climate in general.

The city’s climate data can be explored through detailed climate graphs and weather averages. These resources provide comprehensive insights into monthly weather conditions, making it easier for travelers to plan their visits.

With this information at hand, readers are well-equipped to understand and appreciate the diverse weather in Hiroshima, Japan.

Average Temperature in Hiroshima, Japan

Hiroshima experiences a wide range of temperatures throughout the year.

The hottest month is August, with an average high of 88°F and a low of 75°F. January is the coldest month, featuring an average low of 34°F and a high of 47°F.

Below is a table summarizing the average temperatures by month in Fahrenheit:

Month High Temp (°F) Low Temp (°F)
January 47 34
February 49.8 35.6
March 55 42.1
April 65 50
May 73 59
June 81 68
July 87 75
August 88 75
September 82 69
October 72 58
November 61 47
December 51 38

These temperature ranges indicate that Hiroshima has distinct seasons, from hot summers to cold winters. Understanding these patterns is crucial for planning travel or daily activities.

In the summer, the maximum temperature can reach up to 88°F in August. On the coldest nights in January, the temperature often drops to around 28°F.

This shift in temperatures shows the variety people can expect throughout the year in Hiroshima.

Knowing the average temperatures helps anticipate what to wear and how to prepare for the weather.

Average Precipitation in Hiroshima, Japan

Hiroshima experiences significant rainfall throughout the year, with a notable wet season. Snowfall is less frequent but does occur in the colder months.

Average Rainfall in Hiroshima, Japan

Hiroshima receives a considerable amount of rain, especially in the summer months.

June is typically the wettest month, with an average precipitation of about 7 inches.

July and August also see substantial rainfall, averaging around 6 inches and 5 inches respectively. The driest period occurs in winter, particularly in December and January, with average rainfall dropping to about 2 inches.

Month Rainfall (inches)
January 2.1
February 2.6
March 3.9
April 4.7
May 5.2
June 7.0
July 6.0
August 5.0
September 6.5
October 4.8
November 2.9
December 2.1

This pattern shows a clear increase in rainfall during the summer months, contributing to a humid and wet environment.

Average Snow in Hiroshima, Japan

Snowfall in Hiroshima is rare but not unheard of.

The city experiences light snow mostly in January and February. The average monthly snowfall in these months is about 2 inches.

On occasion, snowfall can extend into December and March, but it is typically less significant, averaging less than 1 inch each month.

Hiroshima’s snowfall is characterized by short, sporadic snow events rather than heavy, continuous snow.

The probability of snow and ice accumulation is generally low, making extensive preparations for snow less necessary compared to other regions known for heavier snow.

The relatively mild winters, with limited snow, make Hiroshima less dependent on snow removal infrastructure. The presence of snow adds to the area’s seasonal variety without causing major disruptions.

Average Sun in Hiroshima, Japan

Hiroshima experiences varying amounts of sunshine throughout the year, influenced by seasonal changes. The amount of daily solar energy received fluctuates, being highest during the summer months.

Average Daily Shortwave Solar Energy in Hiroshima, Japan

The amount of sunlight in Hiroshima changes with the seasons.

During summer, particularly in July, the city receives the most sunshine, with long days contributing to an average high of about 7.4 kWh/m².

Winters are shorter, resulting in less sunshine and an average of around 2.6 kWh/m² in December.

Month Average Solar Energy (kWh/m²)
January 2.9
February 3.6
March 4.9
April 5.9
May 6.3
June 6.4
July 7.4
August 7.0
September 5.8
October 4.8
November 3.5
December 2.6

Daily sunshine hours also shift along with the seasons.

For instance, July and August have longer daylight hours due to the summer solstice, offering more chances to enjoy the sun.

December and January, in contrast, are shorter days with fewer hours of sunshine.

Average Humidity in Hiroshima, Japan

Hiroshima experiences varying levels of humidity throughout the year. The relative humidity is a key factor in how the weather feels, with July being the most humid month and April the least humid.

Below is a table with average monthly relative humidity percentages:

Month Average Relative Humidity
January 72%
February 68%
March 64%
April 61%
May 66%
June 72%
July 74%
August 73%
September 73%
October 72%
November 70%
December 70%

July has the highest relative humidity at 74%. During this month, the air feels quite heavy and damp.

In contrast, April is the least humid month, with an average relative humidity of 61%. This makes the weather more comfortable and dry.

The dew point in Hiroshima also fluctuates. A higher dew point indicates more moisture in the air.

For example, the dew point can be quite high in the summer months, adding to the muggy feeling.

Average Wind in Hiroshima, Japan

Wind patterns in Hiroshima vary throughout the year.

For most of the year, the wind speeds stay relatively mild, typically ranging around 5 to 10 mph. These winds are consistent and rarely reach extreme speeds.

Monthly Wind Speeds

Month Average Wind Speed (mph)
January 7
February 8
March 8
April 7
May 6
June 5
July 5
August 6
September 6
October 6
November 7
December 8

Wind speeds are generally higher in the winter months. This season sees averages between 7 to 8 mph.

The windiest month is February, with speeds reaching up to 8 mph.

Summer months experience calmer winds, with June and July seeing averages around 5 mph, making it one of the quietest periods in terms of wind.

Average Air Quality in Hiroshima, Japan

Monthly Air Quality Ratings

Month AQI (Air Quality Index) Primary Pollutant Recommendations
January Moderate (60) PM2.5 Sensitive groups should limit outdoor activity
February Moderate (55) PM2.5
March Moderate (50) PM2.5
April Good (45) Ozone
May Good (40) Ozone
June Good (35) Ozone
July Good (30) Ozone
August Good (35) Ozone
September Moderate (50) PM2.5 Sensitive groups should limit outdoor activity
October Moderate (55) PM2.5
November Moderate (60) PM2.5
December Moderate (65) PM2.5 Sensitive groups should limit outdoor activity

Main Factors Affecting Air Quality

Pressure: Changes in atmospheric pressure can influence the dispersal of pollutants in Hiroshima’s air.

Weather Stations: Data from local weather stations, such as the one at Hiroshima Airport, provide accurate measurements of air quality levels.

Role of Cloud Cover and UV Index

Cloud Cover: Increased cloud cover can sometimes lead to better air quality, as clouds help to trap and break down pollutants.

UV Index: A higher UV index often indicates better air quality, as sunlight helps break down pollutants like ozone and nitrogen dioxide.

Air Quality Reports

The average air quality in Hiroshima remains moderate, with occasional periods of good air quality, particularly during the warmer months.

It’s essential for sensitive groups to monitor air quality reports and take precautions during higher pollution days.

Topography of Hiroshima, Japan

Hiroshima is located in the western part of Honshu, Japan’s largest island. The city is at sea level, bordered by the Seto Inland Sea to the south.

This coastal location provides beautiful ocean views and easy access to maritime activities.

A prominent feature near Hiroshima is Miyajima Island, known for the iconic Itsukushima Shrine. This shrine appears to float on water during high tide, attracting visitors from around the world.

The city also features various hills and mountains, creating diverse landscapes. Hiroshima’s topography is enriched by several rivers, including the Ota River, which flows through the city.

Table of Monthly Precipitation

Month Precipitation (inches)
January 1.9
February 2.6
March 4.1
April 4.9
May 5.8
June 7.6
July 8.9
August 5.0
September 6.9
October 3.9
November 2.5
December 1.7

Local Attractions

  • Peace Memorial Park: A landmark dedicated to the victims of the atomic bomb, the park is located centrally, making it easily accessible.
  • Hiroshima Castle: Also known as Carp Castle, offers panoramic views of the surrounding area.
  • Shukkeien Garden: Known for its scenic elegance and historical significance.

Hiroshima’s topography, combined with its historical sites and natural beauty, makes it a unique destination for both visitors and residents.

Extreme Weather Events That Occur in Hiroshima, Japan

Hiroshima, Japan, experiences various extreme weather events throughout the year, including typhoons, heavy rains, and floods.

Typhoons are common in Hiroshima from June to October. These powerful storms bring strong winds and heavy rainfall, sometimes causing significant damage to infrastructure and leading to floods.

Monthly Rainfall

Month Average Rainfall (inches)
June 7.5
July 9.2
August 7.8
September 8.9
October 5.6

During the summer months, Hiroshima also faces intense heat waves. Temperatures can soar above 90°F, making it one of the hottest periods of the year.

Heavy rainfall in Hiroshima can cause landslides and floods, especially in hilly areas.

For example, torrential rains in July 2018 led to severe flooding and landslides, causing numerous fatalities and significant property damage.

More details can be found in this article about Japan’s worst weather disaster in decades.

Best Time of the Year to Visit Hiroshima, Japan

The best times to visit Hiroshima are during spring and fall. These seasons offer mild weather, beautiful natural scenery, and comfortable temperatures perfect for exploring the city.

What Is Hiroshima, Japan Like in Spring

Spring in Hiroshima spans from March to May. This season is characterized by the blooming of cherry trees, which usually start in late March.

Average temperatures range from 52°F to 77°F, making the weather pleasant for outdoor activities.

March:

  • Avg. High: 57°F
  • Avg. Low: 42°F
  • Rain: 4 Inches

April:

  • Avg. High: 66°F
  • Avg. Low: 51°F
  • Rain: 4 Inches

May:

  • Avg. High: 77°F
  • Avg. Low: 60°F
  • Rain: 5 Inches

The mild weather and vibrant blossoms make spring a perfect time to explore parks and gardens.

What Is Hiroshima, Japan Like in Summer

Summers in Hiroshima, from June to August, are hot and humid. Temperatures can soar up to 89°F in the peak month of August. The rainy season, particularly in June, can bring heavy showers.

June:

  • Avg. High: 80°F
  • Avg. Low: 66°F
  • Rain: 10 Inches

July:

  • Avg. High: 87°F
  • Avg. Low: 73°F
  • Rain: 8 Inches

August:

  • Avg. High: 89°F
  • Avg. Low: 75°F
  • Rain: 6 Inches

Though summer can be challenging due to the heat, tourists can enjoy swimming and coastal activities.

What Is Hiroshima, Japan Like in Fall

Fall, from September to November, offers mild and comfortable weather. This season is marked by beautiful fall foliage that attracts many visitors.

September:

  • Avg. High: 81°F
  • Avg. Low: 68°F
  • Rain: 7 Inches

October:

  • Avg. High: 75°F
  • Avg. Low: 59°F
  • Rain: 5 Inches

November:

  • Avg. High: 63°F
  • Avg. Low: 48°F
  • Rain: 3 Inches

What Is Hiroshima, Japan Like in Winter

Winter in Hiroshima, from December to February, is mild compared to other parts of Japan.

Average temperatures range from 35°F to 54°F, and snowfall is rare.

December:

  • Avg. High: 52°F
  • Avg. Low: 37°F
  • Rain: 3 Inches

January:

  • Avg. High: 47°F
  • Avg. Low: 34°F
  • Rain: 2 Inches

February:

  • Avg. High: 49°F
  • Avg. Low: 35°F
  • Rain: 3 Inches

While winter doesn’t bring extreme cold, it is a quieter season for those who prefer fewer crowds.

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