Hamamatsu Monthly Rainfall & Precipitation
This page shows both the average monthly rainfall and the number of rainy days in Hamamatsu, Shizuoka, Japan. These values are calculated using 30 years of data (1990–2020) to ensure accuracy. Let's now guide you through the details for a complete overview.
Hamamatsu experiences significant rainfall throughout the year, averaging 2086 mm (82 in) of precipitation annually. However, this abundant rainfall is not evenly distributed, with a distinct rainy season during certain months. You can clearly see this in our monthly precipitation graphs below.
Monthly Precipitation Levels
The average number of days each month with precipitation (> 0.2 mm (0.01 in))
The seasons in Hamamatsu, bring significant changes in precipitation. The wettest month, June, receives heavy rainfall, with an average of 276 mm (11 in) of precipitation. This rainfall is distributed across 18 rainy days.
In contrast, the driest month, December, experiences much less rainfall, totaling 75 mm (3 in) over 10 rainy days. These distinct seasonal differences provide diverse experiences throughout the year.June, the wettest month, has a maximum daytime temperature of 27°C (81°F). The city receives 151 hours of sunshine in this period. During the driest month December you can expect a temperature of 14°C (57°F). For more detailed insights into the city's temperatures, visit our Hamamatsu Temperature page.
Daily Historical Precipitation
50-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in July
Explore Hamamatsu's Historical Precipitation: 1976-2026
Browse day-by-day precipitation records for Hamamatsu spanning 51 years. Select any month and year to see actual rainfall and snowfall recorded on each day.
Annual Rainfall in Japan: City Comparison
The map below shows the annual precipitation across Japan. You can also select the different months in case you are interested in a specific month.
heavy rainfall
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Hamamatsu vs World: Rainfall Compared
Hamamatsu's average annual precipitation is 2086 mm (82 in). Let's compare this to some popular worldwide tourist destinations:
In Toronto, Canada, annual precipitation averages 964 mm (38 in), with snowy winters and rainy summers.
In Seoul, South Korea, the average annual precipitation is 1237 mm (49 in), with most rain falling during the summer monsoon season.
In Tokyo, Japan, the average annual precipitation is 1528 mm (60 in), with significant summer rains due to typhoon season.
Kuala Lumpur, Malaysia, receives 2529 mm (100 in) of annual rainfall, characteristic of its equatorial tropical rainforest climate, with consistent rainfall throughout the year and peak months during March and November.
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.
The proximity of a location to a large body of water can significantly affect its rainfall patterns:
- Ocean Influence: Coastal regions typically receive more rainfall due to the presence of moisture-laden winds from the ocean. These regions tend to have more humid climates and experience more frequent precipitation, especially in winter.
- Continental Climates: Areas further from the sea, such as inland or continental regions, experience less frequent rainfall and more extreme seasonal variations in precipitation.
- "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 Hamamatsu's weather, including sunshine hours, humidity levels, and temperature data, visit our Hamamatsu Climate page.
