Onomichi Monthly Rainfall & Precipitation

This page shows both the average monthly rainfall and the number of rainy days in Onomichi, Hiroshima, Japan. The numbers reflect climate data gathered over a 30-year period, from 1990 to 2020. Let's explore the details to provide you with a complete overview.

Onomichi is known for its substantial rain/snowfall, with annual precipitation reaching 1370 mm (54 in).

Monthly Precipitation Levels

The average number of days each month with precipitation (> 0.2 mm (0.01 in))

Significant seasonal changes in precipitation occur throughout the year. During the wettest month, June receives substantial rainfall, averaging 203 mm (8 in) of precipitation, recorded across 16 rainy days.

In contrast, the driest month, January brings less rainfall, with 56 mm (2.2 in) over 16 rainy days.

June, the wettest month, has a maximum daytime temperature of 27°C (81°F). The city receives 155 hours of sunshine in this period. During the driest month January you can expect a temperature of 11°C (52°F). For more detailed insights into the city's temperatures, visit our Onomichi Temperature page.

Onomichi's average annual precipitation is 1370 mm (54 in). Let's compare this to some popular worldwide tourist destinations:

In Lisbon, Portugal, the average annual precipitation is 774 mm (30 in), characterized by wet winters and dry summers typical of the Mediterranean climate.

Osaka, Japan, experiences 1507 mm (59 in) of rainfall annually, spread across the year with wetter summers.

Perth, Australia, receives 565 mm (22 in) of rainfall annually, mostly during the winter months.

Mumbai, India, experiences a tropical monsoon climate with 1860 mm (73 in) of annual rainfall, with the majority of precipitation happening during the monsoon season from June to September.

Precipitation amounts are measured using specific gauges installed at weather stations, collecting both rain and snow and any other type of precipitation. Rainfall is measured directly in millimeters, while that from snow and ice is obtained by melting it. Automated systems often incorporate heaters to make this easier.

Information from these stations is transmitted via Wi-Fi, satellite, GPS, or telephone connections to central monitoring networks. This information is immediately updated and integrated into weather models and forecasts.

Climate change is affecting precipitation patterns worldwide, including Onomichi:

• Changing Rainfall Patterns: Global warming causes drastic changes in the patterns of rainfall. Some areas have been experiencing increased frequency and intensity of rainfall, while other areas experience longer dry spells or even droughts.
• Local Impacts: Many regions are experiencing heavier rainfall in the winter months and drier, hotter summers. This affects agriculture, water resources, and ecosystems.

• "Ginger" was the longest-lasting Atlantic tropical storm, which spun around the open ocean for 28 days in 1971.
• The world's largest snowflake was recorded in the Guinness Book of Records, at 38 cm (15 inches) wide and 20 cm (7.9 inches) thick. The snowflake fell at Fort Keogh, Montana, USA, on 28 January 1887.
• The greatest snowfall recorded was on Mt. Rainier, Washington State, USA, over 31.5 meters (103 feet) fell during the winter of 1972.

For more detailed information about Onomichi's weather, including sunshine hours, humidity levels, and temperature data, visit our Onomichi Climate page.