Portsmouth weather in January 2026

Q: How hot is it in Portsmouth in January?

Daytime temperatures usually reach 29°C in Portsmouth in January with moderate heat and humidity, falling to 21°C at night.

Q: How sunny is it in Portsmouth in January?

There are normally 7 hours of bright sunshine each day in Portsmouth in January - that's 60% of daylight hours.

Q: How warm is the sea around Portsmouth in January?

The average sea temperature around Portsmouth in January is 27°C.

Q: Does it rain in Portsmouth in January?

There are usually 18 days with some rain in Portsmouth in January and the average monthly rainfall is 136mm.

Expect daytime maximum temperatures of 28°C in Portsmouth, Dominica in January based on long-term weather averages. There are 7 hours of sunshine per day on average with 18 days with some rainfall and typically 144 mm of rainfall in the month.

28
28°C max day temperature
7
7 hours of sunshine per day
18
18 days with some rainfall
21
21°C min night temperature
11
11 hours of daylight per day
M
Moderate heat & humidity
144
144 mm of monthly rainfall
9
9 (Very High) UV index
27
27°C sea temperature

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The January weather guide for Dominica (Portsmouth) shows long term weather averages processed from data supplied by CRU (University of East Anglia), the Met Office & the Netherlands Meteorological Institute. Find out more about our data sources.

Metric (°C / mm) | Imperial (°F / inches)

How hot is it in Portsmouth in January?

Daytime temperatures usually reach 29°C in Portsmouth in January with moderate heat and humidity, falling to 21°C at night.

How sunny is it in Portsmouth in January?

There are normally 7 hours of bright sunshine each day in Portsmouth in January - that's 60% of daylight hours.

How warm is the sea around Portsmouth in January?

The average sea temperature around Portsmouth in January is 27°C.

Does it rain in Portsmouth in January?

There are usually 18 days with some rain in Portsmouth in January and the average monthly rainfall is 136mm.

Portsmouth January sunrise & sunset times

Browse the sunrise and sunset times for Portsmouth in January 2026. Select a month to view Portsmouth sunrise and sunset times for the next 12 months.

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