New Hampshire, USA
Long-term weather forecast
Long-term weather forecast

January weather forecast and Climate
Portsmouth, NH

  • The average high temperature in January: 0°C

The warmest month (with the highest average high temperature) is July (26.1°C).
Months with the lowest average high temperature are January and February (0°C).

  • The average low temperature in January: -8.9°C

The month with the highest average low temperature is July (16.1°C).
The coldest month (with the lowest average low temperature) is January (-8.9°C).

  • The average rainfall in January: 87mm

The wettest month (with the highest rainfall) is November (125mm).
The driest month (with the lowest rainfall) is August (70mm).

  • The average rainfall days in January: 11 days

Months with the highest number of rainy days are May and December (12 days).
The month with the lowest number of rainy days is September (8 days).

  • The average sea temperature in January: 5°C

The best month for swimming (with the highest average sea temperature) is August (17°C).
The coldest month (with the lowest average sea temperature) is March (3°C).

  • The average daylight in January: 9h

Months with the longest days are May, June and July (Average daylight: 15h).
Months with shortest days are January and December (Average daylight: 9h).

  • The average sunshine in January: 5h

Months with most sunshine are June, July and August (Average sunshine: 9h).
Months with least sunshine are January, November and December (Average sunshine: 5).

  • The average UV index in January: 1

Months with the highest UV index are June and July (UV index 8).
Months with the lowest UV index are January and December (UV index 1).