Portsmouth monthly weather averages

Average daytime temperature

The bar chart below shows the average monthly peak daytime temperatures at Portsmouth

Portsmouth average temperature chart (Celsius) Portsmouth average temperature chart (Fahrenheit)
Average monthly temperatures in Portsmouth (degrees centigrade and fahrenheit)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
°C 7.4 7.4 9.4 12 15.3 18.5 20.5 20.4 18.1 15.1 10.8 8.5
°F 45.3 45.3 48.9 53.6 59.6 65.3 69 68.7 64.7 59.1 51.5 47.4

Please note: these are the average peak daytime temperatures (usually around mid-afternoon) so do not show daytime / night highs and lows. To see the daily range of temperatures have a look at the temperature max / min chart below.

Average rainfall & rainy days

The graph below shows the average rainfall and number of rainy days per month.

Portsmouth monthly rainfall chart (mm) Portsmouth monthly rainfall chart (inches)
Average monthly rainfall in Portsmouth (mm and inches)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
mm 79 53 60 47 48 44 39 53 63 75 80 78
inches 3.1 2.1 2.3 1.8 1.9 1.7 1.5 2.1 2.5 3 3.1 3.1
Rainy days 17 12 14 12 12 10 9 10 11 14 15 16

Average daily sunshine

The bar chart below shows the average daily sunshine hours in Portsmouth

Portsmouth average daily sunshine chart
Average daily sunshine Portsmouth
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Hrs sunshine 2.3 3.2 4.6 6.4 7.9 8.3 8.2 7.6 6 4.3 3.1 2.3

Day / night temperatures

The graph below shows the daily range of temperatures for each month.

Portsmouth average minimum / maximum temperatures (Celsius) Portsmouth average minimum / maximum temperatures (Fahrenheit)
Maximum and minimum daily temperatures in Portsmouth (degrees centigrade and fahrenheit)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Min °C 2.9 2.7 3.7 5.5 8.5 11.6 13.5 13.7 11.9 9.6 5.9 4
Max °C 7.5 7.5 9.5 12.2 15.5 18.7 20.7 20.6 18.3 15.2 11 8.7
Min °F 37.2 36.9 38.7 41.8 47.3 52.8 56.3 56.6 53.4 49.3 42.5 39.1
Max °F 41.4 41.2 43.9 47.8 53.6 59.2 62.8 62.8 59.2 54.3 47.1 43.3

Sea temperature

The graph below shows the average sea temperature.

Portsmouth average sea temperature chart (Celsius) Portsmouth average sea temperature chart (Fahrenheit)
Average sea temperature around Portsmouth in degrees centigrade and fahrenheit
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
°C 9.6 8.6 8.5 9.5 11.2 13.5 15.6 16.9 16.9 15.7 13.6 11.4
°F 49.3 47.4 47.3 49.1 52.2 56.3 60.1 62.4 62.3 60.2 56.6 52.5

Wind speed

The graph below shows the average wind speed.

Portsmouth average winspeed by month (km/h) Portsmouth average winspeed by month (mph)
Average wind speed in Portsmouth (mph and kmh)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
km/h 17 17 17 16 15 14 14 14 14 14 16 17
mph 11 11 11 10 9 9 9 9 9 9 10 11

A monthly average windspeed of over 16km/h or 10mph suggests a location is fairly windy.

Relative humidity

The graph below shows the average relative humidity.

Portsmouth relative humidity averages
Average relative humidity in Portsmouth
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
91% 89% 86% 83% 83% 82% 82% 82% 86% 88% 90% 92%

Other monthly averages

UV index Best time to go?

Portsmouth weather stats

Portsmouth weather statistics
Hottest month: July 20.5°C 68.9°F
Driest month: July 39mm 1.5ins
Sunniest month: August 7.6hrs
Coldest month: February 7.4°C 45.3°F
Wettest month: November 80mm 3.1ins
Warmest sea: August 16.9°C 62.4°F
Map showing location of Portsmouth (50.79899, -1.09125)

Locations nearby

Top United Kingdom locations

Change units