Cornwall (ON) Monthly Rainfall & Precipitation

This page shows both the average monthly rainfall and the number of rainy days in Cornwall, Ontario, Canada. The figures are based on a 30-year period (1990–2020) to provide a reliable average. Let's explore the details to provide you with a complete overview.

Cornwall is known for its substantial rain/snowfall, with annual precipitation reaching 1006 mm (40 in).

Monthly Precipitation Levels

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

The amount of precipitation varies moderately throughout the year. The wettest month, October, sees around 115 mm (4.5 in) of rainfall, perfect for those who enjoy a bit of rain now and then. The driest month, March, still receives a respectable 57 mm (2.2 in) of snow/rainfall.

October, the wettest month, has a maximum daytime temperature of 14°C (57°F). During the driest month March you can expect a temperature of 3°C (37°F). For more detailed insights into the city's temperatures, visit our Cornwall Temperature page.

Cornwall's average annual precipitation is 1006 mm (40 in). Let's compare this to some popular worldwide tourist destinations:

Athens, Greece, receives an average annual precipitation of 400 mm (16 in), making it one of the drier Mediterranean climates with rainfall mostly in winter.

In Seoul, South Korea, the average annual precipitation is 1237 mm (49 in), with most rain falling during the summer monsoon season.

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.

• Mawsynram in India is noted as being the wettest place on earth, with over 11 meters (36 feet) of rain falling every year.
• In contrast, Antofagasta in Chile is among the driest places on the planet, getting less than 0.1mm (0.004 inches) per year, with some years recording virtually no rainfall.
• Nearly 1,650 thunderstorm cells are estimated over the planet at any given time.

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