Portsmouth (VA) Monthly Rainfall & Precipitation

This page shows both the average monthly rainfall and the number of rainy days in Portsmouth, Virginia, United States of America. These averages rely on historical data collected over 30 years, from 1990 to 2020. Now, let's explore all the details to give you a full picture.

Portsmouth experiences significant rain/snowfall throughout the year, averaging 1339 mm (53 in) of precipitation annually.

Monthly Precipitation Levels

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

Portsmouth can be quite wet during September, receiving approximately 170 mm (6.7 in) of precipitation over 10 rainy days.

In contrast February, experiences much drier conditions, with 70 mm (2.8 in) of rainfall, spread across 9 rainy days.

September, the wettest month, has a maximum daytime temperature of 28°C (82°F). The city receives 230 hours of sunshine in this period. During the driest month February you can expect a temperature of 11°C (52°F). For more detailed insights into the city's temperatures, visit our Portsmouth Temperature page.

Portsmouth's average annual precipitation is 1339 mm (53 in). Let's compare this to some popular worldwide tourist destinations:

New York City, USA, receives 1276 mm (50 in) of rainfall annually, with precipitation evenly distributed throughout the year.

Beijing, China, receives 560 mm (22 in) of annual precipitation, concentrated in the summer months.

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 Portsmouth (VA):

• 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.

• The U.S. has a significant number of thunderstorms every year, with over 14.6 million taking place across the world annually.
• Approximately 70% of lightning bolts strike land rather than oceans.
• A storm named John was the longest-lasting Pacific tropical storm, continuing for 31 days. As it crossed the dateline twice, it changed status from a hurricane to a typhoon and back to a hurricane.

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