Portsmouth Weather & Climate: Best Time to Visit

In Portsmouth temperatures are generally consistent throughout the year. On average, daytime temperatures range from a comfortable 29°C (84°F) in September to a comfortable 27°C (81°F) in February.

Nighttime temperatures range from 26°C (79°F) in September to 24°C (75°F) in February.

Check out our detailed temperature page for more information.

Temperature ranges by month

On average, Portsmouth receives a reasonable amount of rainfall, with an annual precipitation of 973 mm (38 in). The seasons in Portsmouth bring significant changes in precipitation. The wettest month, October, receives high rainfall, with an average of 137 mm (5.4 in) of precipitation. This rainfall is distributed across 19 rainy days.

In contrast, the driest month, March, experiences much less rainfall, totaling 33 mm (1.3 in) over 15 rainy days. These distinct seasonal differences provide diverse experiences throughout the year. For more details, please visit our Portsmouth Precipitation page.

The mean monthly precipitation over the year, including rain, hail, and snow

The average number of days each month with precipitation

Portsmouth enjoys sunny spells year-round. April sees up to 8.2 hours of daily sunshine, perfect for a sunny trip. December, the least sunny month, still offers a generous 6.3 hours of sun despite this cloudier time of the year.

Visit our detailed sunshine hours page for more information.

Monthly hours of sunshine

Daily hours of sunshine

The relative humidity is high throughout the year in Portsmouth.

The city experiences its highest humidity in November, reaching 74%. In April, the humidity drops to its lowest level at 64%. What does this mean? Read our detailed page on humidity levels for further details.

Relative humidity over the year