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Hourly Forecast
Daylight Hours
06:29
Sunrise
18:45
Sunset
Moon
Waxing Crescent
11:25
Moonrise
20:10
Moonset
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Weather in Portsmouth tomorrow, September 16, 2026
Conditions in Portsmouth on September 16, 2026 favour clear skies, so the day opens with a fine, sunny outlook. Any interruptions to the blue should be brief rather than lasting. Cloud leads the morning, peaking close to 100% near 08:00. Sunshine has little room until later in the day.
Temperatures climb from an overnight low near 11°C toward a daytime high of about 25°C. Expect humidity between 48% and 97%, most humid near 06:00. Winds stay light, near 12.2 km/h by 14:00, so the day feels still more than breezy.
Afternoon conditions open up, holding cloud close to 36% near 15:00. The day finishes on a milder, brighter note. Visibility holds near 15.1 km, though it can fall to 11.2 km. The sun rises at 06:30 and sets at 18:43, for a total of 12 hours 13 minutes of sunlight today.
Overall, Portsmouth on September 16, 2026 favours outdoor plans under mostly open skies, with a comfortable high near 25°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 25°C. The average temperature during this period is around 22°C.
How cold does it get in Portsmouth?
The coldest month in Portsmouth is January, with average low temperatures of -4°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 December, with an average of 129mm of precipitation.
What is the driest time of year in Portsmouth?
The driest month in Portsmouth is September, with an average of 75mm of precipitation.
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