Portsmouth weather live forecast

Today's maximum temperature in Portsmouth is expected to be 24°C. Select a day from the live weather forecast for Portsmouth, New Hampshire, USA for more weather parameters.

5-day weather forecast updated at 04:04 on Thursday 18th September 2025 GMT

More about Portsmouth

Portsmouth by month

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Recommended for New Hampshire

Cosmos: Tour deal finder - low prices

  • Explore best prices on Cosmos tours worldwide
  • Find deals on tour holidays in 2025/2026
  • Filter by price, destination, duration & more
Go to Cosmos deal >>

View all Cosmos offers

The 5-day weather forecast for New Hampshire (Portsmouth) is provided by the Swiss meteorological agency, meteoblue. Find out more about our data sources.

Portsmouth weather forecast by day

Below are the detailed weather forecasts for Portsmouth for the next 5 days.

Portsmouth weather for Thursday 18th September 2025

Expect scattered clouds in Portsmouth, New Hampshire with a maximum temperature of 24°C, maximum UV of 5 (Moderate) and 8 hours of bright sunshine. There are 0 mm of rainfall expected and a light breeze of 7 kph from the south.

  • 24°C maximum temperature24
    °C maximum temperature
  • 14°C minimum temperature14
    °C minimum temperature
  • Scattered clouds
    scattered clouds
  • 8 hours of bright sunshine8
    hours of sunshine
  • UV (maximum) index 5 (Moderate)5
    UV index (Moderate)
  • 0 mm of rainfall expected0
    mm of rainfall expected
  • 24°C wind chill24
    °C wind chill
  • Light breeze of 7 kph from the South7
    kph wind from S

Back to top

Portsmouth weather for Friday 19th September 2025

Expect scattered clouds in Portsmouth, New Hampshire with a maximum temperature of 23°C, maximum UV of 5 (Moderate) and 8 hours of bright sunshine. There are 0 mm of rainfall expected and a gentle breeze of 15 kph from the north-west.

  • 23°C maximum temperature23
    °C maximum temperature
  • 12°C minimum temperature12
    °C minimum temperature
  • Scattered clouds
    scattered clouds
  • 8 hours of bright sunshine8
    hours of sunshine
  • UV (maximum) index 5 (Moderate)5
    UV index (Moderate)
  • 0 mm of rainfall expected0
    mm of rainfall expected
  • No heat & humidity0
    no heat & humidity
  • Gentle breeze of 15 kph from the North-West15
    kph wind from NW

Back to top

Portsmouth weather for Saturday 20th September 2025

Expect clear skies in Portsmouth, New Hampshire with a maximum temperature of 17°C, maximum UV of 6 (High) and 12 hours of bright sunshine. There are 0 mm of rainfall expected and a light breeze of 8 kph from the north.

  • 17°C maximum temperature17
    °C maximum temperature
  • 9°C minimum temperature9
    °C minimum temperature
  • Clear skies
    clear skies
  • 12 hours of bright sunshine12
    hours of sunshine
  • UV (maximum) index 6 (High)6
    UV index (High)
  • 0 mm of rainfall expected0
    mm of rainfall expected
  • No heat & humidity0
    no heat & humidity
  • Light breeze of 8 kph from the North8
    kph wind from N

Back to top

Portsmouth weather for Sunday 21st September 2025

Expect clear skies in Portsmouth, New Hampshire with a maximum temperature of 19°C, maximum UV of 5 (Moderate) and 12 hours of bright sunshine. There are 0 mm of rainfall expected and a gentle breeze of 13 kph from the south.

  • 19°C maximum temperature19
    °C maximum temperature
  • 6°C minimum temperature6
    °C minimum temperature
  • Clear skies
    clear skies
  • 12 hours of bright sunshine12
    hours of sunshine
  • UV (maximum) index 5 (Moderate)5
    UV index (Moderate)
  • 0 mm of rainfall expected0
    mm of rainfall expected
  • 19°C wind chill19
    °C wind chill
  • Gentle breeze of 13 kph from the South13
    kph wind from S

Back to top

Portsmouth weather for Monday 22nd September 2025

Expect scattered clouds in Portsmouth, New Hampshire with a maximum temperature of 21°C, maximum UV of 5 (Moderate) and 11 hours of bright sunshine. There are 0 mm of rainfall expected and a gentle breeze of 13 kph from the south.

  • 21°C maximum temperature21
    °C maximum temperature
  • 9°C minimum temperature9
    °C minimum temperature
  • Scattered clouds
    scattered clouds
  • 11 hours of bright sunshine11
    hours of sunshine
  • UV (maximum) index 5 (Moderate)5
    UV index (Moderate)
  • 0 mm of rainfall expected0
    mm of rainfall expected
  • No heat & humidity0
    no heat & humidity
  • Gentle breeze of 13 kph from the South13
    kph wind from S

Back to top

Radisson Hotels: up to 25% off prepaid rates

  • Save up to 25% on hotel stays when you book advance
  • Radisson Rewards members get extra 10% off hotels
  • Book hotels in Europe, Middle East, Africa, Asia & Pacific
Show discount codeShow discount code ******AID
Redeem Radisson Hotels discount code >>

View all Radisson Hotels offers

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

Back to top

More about the USA

Related posts

Popular travel offers

Explore holiday destinations

More holidays

Save with latest deals & discounts

More deals

Airport parking

More parking

Airport lounges

More lounges

Top ^