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

March 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
March, the first month of the spring, in Portsmouth, is still a cold month, with temperature in the range of an average high of 41°F (5°C) and an average low of 27°F (-2.8°C).

Temperature

In Portsmouth, the average high-temperature increases, from a wintry 32°F (0°C) in February, to a still cold 41°F (5°C). In Portsmouth, the average low-temperature is 27°F (-2.8°C).

Rainfall

In Portsmouth, during 11 rainfall days, 3.4" (87mm) 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

The month with the coldest seawater in Portsmouth is March, with an average ocean temperature of 38.5°F (3.6°C). For swimming, this is considered life-threatening and very dangerous. The water feels painfully cold, and hyperventilation quickly occurs. A specialized swimsuit is mandatory to reduce thermal damage.

Daylight

In Portsmouth, the average length of the day is 12h.

Sunshine

In Portsmouth, New Hampshire, the average sunshine in March is 7h.

UV index

In Portsmouth, the average daily maximum UV index in March is 3. A UV Index reading of 3 to 5 represents a medium health hazard from unsafe exposure to the UV radiation for the ordinary person.
The average daily UV index of 3 transform into the following instructions:
Take precautions - Protection against the skin and eye damage is obliged. The solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. 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 March in Portsmouth?

In March, the average high-temperature is 41°F (5°C), and the average low-temperature is 27°F (-2.8°C).

How many days does it rain in March in Portsmouth?

In Portsmouth, in March, during 11 rainfall days, 3.4" (87mm) of precipitation is typically accumulated.

What is the month with the coldest ocean in Portsmouth?

The month with the coldest seawater in Portsmouth is March, with an average ocean temperature of 38.5°F (3.6°C). For swimming, this is considered very dangerous and immediately life-threatening. Total loss of breathing control instantly occurs, and clear thinking becomes almost impossible. A specialized swimsuit is obligatory to minimize thermal loss.

What is the ocean temperature in March in Portsmouth?

In Portsmouth, New Hampshire, the average seawater temperature in March is 38.5°F (3.6°C). For swimming, this is considered extremely cold, dangerous, and life-threatening. Unless suitably protected with insulated waterproof clothing, hypothermia quickly occurs.

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

In March, the average length of the day in Portsmouth, New Hampshire, is 12h.

How long on average sun shines in March in Portsmouth?

In Portsmouth, the average sunshine in March is 7h.

What is the UV index reading in March in Portsmouth?

The average daily maximum UV index in March in Portsmouth, New Hampshire, is 3. A UV Index estimate of 3 to 5 represents a moderate vulnerability from the exposure to the Sun's UV radiation.
Average temperature in March - Portsmouth, NH
  • Average high temperature in March: 41°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 March: 27°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 March - Portsmouth, NH
  • Average rainfall in March: 3.4"

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 March - Portsmouth, NH
  • Average rainfall days in March: 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 March - Portsmouth, NH
  • Average sea temperature in March: 38.5°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 March / Average sunshine in March - Portsmouth, NH
  • Average daylight in March: 12h

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 March: 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 March - Portsmouth, NH
  • Average UV index in March: 3

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).