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

August weather forecast and Climate
Portsmouth, NH

  • The average high temperature in August: 77°F

The warmest month (with the highest average high temperature) is July (79°F).
Months with the lowest average high temperature are January and February (32°F).

  • The average low temperature in August: 59°F

The month with the highest average low temperature is July (61°F).
The coldest month (with the lowest average low temperature) is January (16°F).

  • The average rainfall in August: 2.8"

The wettest month (with the highest rainfall) is November (4.9").
The driest month (with the lowest rainfall) is August (2.8").

  • The average rainfall days in August: 10 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 August: 65.6°F

The best month for swimming (with the highest average sea temperature) is August (65.6°F).
The coldest month (with the lowest average sea temperature) is March (38.5°F).

  • The average daylight in August: 14h

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 August: 9h

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 August: 7

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).