Portsmouth
United Kingdom
Long-term weather forecast
Long-term weather forecast

May weather forecast and climate
Portsmouth, United Kingdom

The last month of the spring, May, is an enjoyable month in Portsmouth, United Kingdom, with temperature in the range of an average low of 9.2°C (48.6°F) and an average high of 16.7°C (62.1°F).

Temperature

In May, the average high-temperature slightly increases, from a moderate 13.2°C (55.8°F) in April, to a comfortable 16.7°C (62.1°F). In May, in Portsmouth, the average low-temperature is 9.2°C (48.6°F).

Rainfall

In Portsmouth, during 6.5 rainfall days, 43.4mm (1.7") of precipitation is typically accumulated. In Portsmouth, during the entire year, the rain falls for 103.4 days and collects up to 699mm (27.5") of precipitation.

Sea temperature

In Portsmouth, the average water temperature is 11.5°C (52.7°F).
Note: Swimming in 11.5°C (52.7°F) is considered dangerous. Unprotected immersion in temperatures below 10°C (50°F) causes quickly maximum intensity cold shock with hyperventilation.

Daylight

In May, the average length of the day in Portsmouth is 15.5h.

Sunshine

In May, the average sunshine in Portsmouth is 7.8h.

UV index

May through August, with an average maximum UV index of 6, are months with the highest UV index. A UV Index estimate of 6 to 7 represents a high health vulnerability from the exposure to the Sun's UV rays for the ordinary person.
Note: The average daily UV index of 6 transform into the following instructions:
Take precautions and adopt sun safety practices. Protection against sunburn is obliged. The Sun's UV radiation is most powerful between 10 a.m. and 4 p.m. To the extent possible, limit exposure to the direct sun during these hours. Sun-protective clothing, a long-sleeved shirt and pants, a wide-brimmed hat, and UVA and UVB-blocking sunglasses are particularly helpful in blocking UV radiation's harmful effects.

What is the temperature in May in Portsmouth?

The average high-temperature, in May, in Portsmouth, United Kingdom, is 16.7°C (62.1°F), while the average low-temperature is 9.2°C (48.6°F).

How many days does it rain in May in Portsmouth?

In Portsmouth, United Kingdom, in May, it is raining for 6.5 days, with typically 43.4mm (1.7") of accumulated precipitation.

How cold is the water in May in Portsmouth?

In Portsmouth, in May, the average water temperature is 11.5°C (52.7°F). Swimming in 11.5°C (52.7°F) is considered life-threatening. Even a few minutes in 13°C (55.4°F) water is uncomfortable, and swimming below 10°C (50°F) may cause total loss of breathing control and cold shock, depending on a person's physique.

How many hours of daylight does Portsmouth have in May?

The average length of the day in May is 15.5h.

How long on average sun shines in May in Portsmouth?

In Portsmouth, United Kingdom, the average sunshine in May is 7.8h.

What are the months with the highest UV index in Portsmouth?

Months with the highest UV index are May through August, with an average maximum UV index of 6.

How high is the UV index in May in Portsmouth?

In May, the average daily maximum UV index in Portsmouth is 6. A UV Index value of 6 to 7 symbolizes a high health threat from the exposure to the Sun's UV rays.
Average temperature in May - Portsmouth, United Kingdom
  • Average high temperature in May: 16.7°C

Warmest months (with the highest average high temperature) are July and August (21.4°C).
Months with the lowest average high temperature are January and February (8.2°C).

  • Average low temperature in May: 9.2°C

The month with the highest average low temperature is August (14.3°C).
The coldest month (with the lowest average low temperature) is February (2.8°C).

Average rainfall in May - Portsmouth, United Kingdom
  • Average rainfall in May: 43.4mm

The wettest month (with the highest rainfall) is October (86.2mm).
The driest month (with the lowest rainfall) is June (42mm).

Average rainfall days in May - Portsmouth, United Kingdom
  • Average rainfall days in May: 6.5 days

Months with the highest number of rainy days are January and December (11.2 days).
The month with the lowest number of rainy days is July (5.4 days).

Average sea temperature in May - Portsmouth, United Kingdom
  • Average sea temperature in May: 11.5°C

The best month for swimming (with the highest average sea temperature) is September (17.3°C).
The coldest month (with the lowest average sea temperature) is March (8.6°C).

Average daylight in May / Average sunshine in May - Portsmouth, United Kingdom
  • Average daylight in May: 15.5h

The month with the longest days is June (Average daylight: 16.4h).
The month with shortest days is December (Average daylight: 8h).

  • Average sunshine in May: 7.8h

The month with most sunshine is July (Average sunshine: 8.4h).
The month with least sunshine is December (Average sunshine: 2h).

Average UV index in May - Portsmouth, United Kingdom
  • Average UV index in May: 6

Months with the highest UV index are May, June, July and August (UV index 6).
Months with the lowest UV index are January, February, November and December (UV index 1).