Princeton (NJ) Monthly Rainfall & Precipitation

This page shows both the average monthly rainfall and the number of rainy days in Princeton, New Jersey, United States of America. The numbers reflect climate data gathered over a 30-year period, from 1990 to 2020. Now, let's explore all the details to give you a full picture.

Princeton is known for its substantial rain/snowfall, with annual precipitation reaching 1267 mm (50 in).

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. July brings wetter days averaging 138 mm (5.4 in) of precipitation, spread over 12 rainy days.

In contrast, February experiences a drier climate, with about 76 mm (3 in) of snow/rainfall spread across 10 snowy/rainy days.

July, the wettest month, has a maximum daytime temperature of 31°C (88°F). The city receives 269 hours of sunshine in this period. During the driest month February you can expect a temperature of 5°C (41°F). For more detailed insights into the city's temperatures, visit our Princeton 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.

Annual

Annual

Map not visible? Whoops sorry! Please refresh the page.

Legend

heavy rainfall

high

moderate

low

almost none

Heavy annual rainfall has been defined as more than 1000 mm (39 in) precipitation. High: 600 mm (24 in) to 1000 mm (39 in). Moderate: 250 mm (9.8 in) to 600 mm (24 in). Low: less than 250 mm (9.8 in).

Princeton vs World: Rainfall Compared

Princeton's average annual precipitation is 1267 mm (50 in). Let's compare this to some popular worldwide tourist destinations:

The climate in San Francisco, USA, is influenced by coastal weather, with 469 mm (18 in) of rainfall mostly during the winter months.

In Shanghai, China, the annual average precipitation is 1347 mm (53 in), with a humid subtropical climate.

Adelaide, Australia, enjoys 511 mm (20 in) of annual precipitation, with dry summers and wet winters.

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.

How is Precipitation Measured?

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.

Rainy Seasons: Many parts of the world have well-defined wet seasons where precipitation is distinctly higher. These are normally accompanied by lush vegetation and temperature patterns.

Dry Seasons: In areas where the climate is either desert or Mediterranean, the amount of precipitation is drastically reduced, leading to a shortage of water and arid conditions.

Interesting weather facts

"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 Princeton (NJ)'s weather, including sunshine hours, humidity levels, and temperature data, visit our Princeton (NJ) Climate page.

Current rainfall in Princeton (NJ)

10-Day Forecast