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Hourly Forecast
Daylight Hours
06:49
Sunrise
19:07
Sunset
Moon
Waxing Crescent
13:18
Moonrise
20:49
Moonset
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Weather in Portsmouth today, September 16, 2026
Portsmouth stays under cloudy skies on September 16, 2026, with only brief brighter breaks. Plan for a day that feels grey more often than open.
Expect highs of 20°C and cooler readings close to 13°C. Moisture in the air spans 51%-75%, with the highest values around 23:00. Expect gentle winds, highest near 14:00 at 4.5 km/h.
The afternoon keeps an overcast feel, as cloud reaches about 100% around 19:00. Outdoor plans may still want a flexible backup. Expect visibility near 39.5 km, with poorer spells close to 35.6 km. Daylight runs from 06:49 to 19:07, lasting 12 hours 17 minutes of sunlight today.
Overall, Portsmouth on September 16, 2026 stays grey and muted, so outdoor plans may want a flexible backup even with a high near 20°C.
Frequently asked questions about weather in Portsmouth
How warm does it get in Portsmouth?
The warmest month in Portsmouth is August, with average high temperatures of 20°C. The average temperature during this period is around 18°C.
How cold does it get in Portsmouth?
The coldest month in Portsmouth is January, with average low temperatures of 5°C. The average temperature during this period is around 7°C.
What is the wettest time of year in Portsmouth?
The wettest month in Portsmouth is October, with an average of 106mm of precipitation.
What is the driest time of year in Portsmouth?
The driest month in Portsmouth is April, with an average of 43mm of precipitation.
