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

April weather forecast and climate
Portsmouth, NH

Bright neon lights and buildings next to the very calm waters of the iconic Piscataqua River in Portsmouth, New Hampshire, the clear dusk sky in close up view
Bright neon lights and buildings next to the very calm waters of the iconic Piscataqua River in Portsmouth, New Hampshire, the clear dusk sky in close up view
April in Portsmouth, New Hampshire, is a fresh spring month, with temperature in the range of an average low of 36°F (2.2°C) and an average high of 52°F (11.1°C).

Temperature

In Portsmouth, the average high-temperature in April rises, from a wintry 41°F (5°C) in March, to a cool 52°F (11.1°C). The average low-temperature, in April, is 36°F (2.2°C).

Rainfall

In Portsmouth, in April, during 11 rainfall days, 3.6" (92mm) of precipitation is typically accumulated. In Portsmouth, during the entire year, the rain falls for 125 days and collects up to 42.4" (1078mm) of precipitation.

Ocean temperature

In Portsmouth, the average water temperature is 42.4°F (5.8°C). At temperatures below 50°F (10°C), swimming in a suitably protected swimsuit is feasible; otherwise, cold shock and loss of breathing control are imminent. Even a short swim, without thermal protection, at temperatures around 55.4°F (13°C) is not comfortable.

Daylight

The average length of the day in Portsmouth is 13.4h.

Sunshine

In Portsmouth, the average sunshine is 7h.

UV index

The average daily maximum UV index in Portsmouth is 5. A UV Index of 3 to 5 symbolizes a moderate threat to health from the exposure to the Sun's UV rays for average individuals.
The daily maximum UV index of 5 interpret into the following advice:
Take precautions. Light skin individuals may get burned in less than 30 minutes. The Sun's most intense and consequently most harmful UV radiation during midday hours should be decreased by minimizing exposure and seeking shade. A wide-brim hat offers excellent sun protection for eyes, ears, face, and neck. Sunglasses with UVA and UVB protection significantly reduce eye damage from sun exposure. Tightly woven, loose-fitting clothes provide additional protection from the Sun.

What is the temperature in April in Portsmouth?

In Portsmouth, in April, the average high-temperature is 52°F (11.1°C), and the average low-temperature is 36°F (2.2°C).

How much does it rain in Portsmouth in April?

In Portsmouth, in April, it is raining for 11 days, with typically 3.6" (92mm) of accumulated precipitation.

How cold is the water in April in Portsmouth?

In Portsmouth, the average seawater temperature in April is 42.4°F (5.8°C). Swimming in 42.4°F (5.8°C) is considered dangerous. Unprotected immersion in temperatures below 50°F (10°C) causes quickly maximum intensity cold shock with hyperventilation.

What is the average length of the day in April in Portsmouth?

In Portsmouth, the average length of the day in April is 13.4h.

How many hours of sunshine does Portsmouth have in April?

The average sunshine in April is 7h.

How high is the UV index in April in Portsmouth?

In Portsmouth, New Hampshire, the average daily maximum UV index in April is 5. A UV Index estimate of 3 to 5 represents a moderate health threat from unprotected exposure to the UV radiation.
Average temperature in April - Portsmouth, NH
  • Average high temperature in April: 52°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).

  • Average low temperature in April: 36°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).

Average rainfall in April - Portsmouth, NH
  • Average rainfall in April: 3.6"

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

Average rainfall days in April - Portsmouth, NH
  • Average rainfall days in April: 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).

Average sea temperature in April - Portsmouth, NH
  • Average sea temperature in April: 42.4°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).

Average daylight in April / Average sunshine in April - Portsmouth, NH
  • Average daylight in April: 13.4h

The month with the longest days is June (Average daylight: 15.3h).
The month with shortest days is December (Average daylight: 9.1h).

  • Average sunshine in April: 7h

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

Average UV index in April - Portsmouth, NH
  • Average UV index in April: 5

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).