Dennis Monthly Rainfall & Precipitation
This page shows both the average monthly rainfall and the number of rainy days in Dennis, Cape Cod, United States of America. 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.
Dennis has a relatively rain/snowy climate with high precipitation levels, averaging 1240 mm (49 in) of rain/snowfall annually.
Monthly Precipitation Levels
The average number of days each month with precipitation (> 0.2 mm (0.01 in))
While rainfall varies throughout the year, each season offers its own charm. December brings wetter days averaging 138 mm (5.4 in) of precipitation, spread over 14 rainy days.
In contrast, August experiences a drier climate, with about 80 mm (3.1 in) of rainfall spread across 9 rainy days.
December, the wettest month, has a maximum daytime temperature of 8°C (46°F). The city receives 147 hours of sunshine in this period. During the driest month August you can expect a temperature of 26°C (79°F). For more detailed insights into the city's temperatures, visit our Dennis Temperature page.
Annual Rainfall in the United States of America: City Comparison
The map below shows the annual precipitation across the United States of America. You can also select the different months in case you are interested in a specific month.
heavy rainfall
high
moderate
low
almost none
Dennis vs World: Rainfall Compared
Dennis's average annual precipitation is 1240 mm (49 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 Shanghai, China, the annual average precipitation is 1347 mm (53 in), with a humid subtropical climate.
Melbourne, Australia, has 690 mm (27 in) of rainfall annually, spread fairly evenly throughout the year.
Bangkok, Thailand, experiences a tropical monsoon climate with 1668 mm (66 in) of annual rainfall, with the heaviest precipitation occurring during September and October.
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 Dennis's weather, including sunshine hours, humidity levels, and temperature data, visit our Dennis Climate page.