Portsmouth Weather & Climate: Best Time to Visit

In Portsmouth, temperatures differ significantly between summer and winter months. Typically, average maximum daytime temperatures range from a very warm 32°C (90°F) in July to a chilly 10°C (50°F) in the coolest month, February.

Nights vary from 22°C (72°F) in July to around 0°C (32°F) during the colder months.

Check out our detailed temperature page for more information.

Temperature ranges by month

Portsmouth experiences significant rain/snowfall throughout the year, averaging 1339 mm (53 in) of precipitation annually. The climate in Portsmouth shows significant variation throughout the year. Expect heavy rainfall in September, the wettest month, with an average of 170 mm (6.7 in) of precipitation over 10 rainy days.

In contrast, the driest month February offers drier and sunnier days, with around 70 mm (2.8 in) of rainfall over 9 rainy days. 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

For those who appreciate different seasons, Portsmouth serves as an ideal destination. Expect longer, more sun-filled days in June with an average of 9.4 hours of sunshine daily, and embrace the darker days in December, offering only 5.3 hours of daily sunlight.

Visit our detailed sunshine hours page for more information.

Monthly hours of sunshine

Daily hours of sunshine

Daily percentage of sunshine

The relative humidity is high throughout the year in Portsmouth.

The city experiences its highest humidity in August, reaching 74%. In April, the humidity drops to its lowest level at 62%. What does this mean? Read our detailed page on humidity levels for further details.

Relative humidity over the year