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Hourly Forecast
Daylight Hours
07:19
Sunrise
19:33
Sunset
Moon
Waxing Crescent
12:03
Moonrise
21:12
Moonset
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Weather in Portsmouth tomorrow, September 16, 2026
Portsmouth starts September 16, 2026 under largely sunny skies, with bright spells setting the tone from the outset. Outdoor plans should enjoy long stretches of open sky as the day unfolds. The morning sky stays heavily clouded, with cover near 100% around 09:00. Grey conditions set the early tone before any later change.
Temperatures climb from an overnight low near 19°C toward a daytime high of about 31°C. Relative humidity sits between 31% and 77%, reaching its peak around 07:00. Expect gentle winds, highest near 15:00 at 9.7 km/h.
Through the afternoon skies look more workable, with cloud near 25% around 14:00. Later outdoor plans have a clearer window than the morning may have suggested. Horizontal visibility holds close to 16.1 km. Sunrise is at 07:20 and sunset at 19:31, giving 12 hours 11 minutes of sunlight today.
Taken together, settled sunshine in Portsmouth on September 16, 2026 makes outdoor timing easier, with highs near 31°C.
Frequently asked questions about weather in Portsmouth
How warm does it get in Portsmouth?
The warmest month in Portsmouth is July, with average high temperatures of 30°C. The average temperature during this period is around 25°C.
How cold does it get in Portsmouth?
The coldest month in Portsmouth is January, with average low temperatures of -2°C. The average temperature during this period is around 1°C.
What is the wettest time of year in Portsmouth?
The wettest month in Portsmouth is May, with an average of 135mm of precipitation.
What is the driest time of year in Portsmouth?
The driest month in Portsmouth is November, with an average of 78mm of precipitation.
