Portstewart monthly weather averages

Average daytime temperature

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

Portstewart average temperature chart (Celsius) Portstewart average temperature chart (Fahrenheit)
Average monthly temperatures in Portstewart (degrees centigrade and fahrenheit)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
°C 6.5 6.6 8.4 10.7 13.4 16 17.1 17.1 15.2 12.6 8.8 7.3
°F 43.6 43.8 47.1 51.3 56.1 60.8 62.9 62.8 59.3 54.6 47.9 45.1

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.

Portstewart monthly rainfall chart (mm) Portstewart monthly rainfall chart (inches)
Average monthly rainfall in Portstewart (mm and inches)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
mm 121 84 93 66 71 71 76 92 105 123 113 113
inches 4.8 3.3 3.7 2.6 2.8 2.8 3 3.6 4.1 4.8 4.5 4.5
Rainy days 22 17 20 17 17 17 18 20 20 22 22 22

Average annual rainfall in Portstewart: 1176.5665mm (463.2 inches)

Average daily sunshine

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

Portstewart average daily sunshine chart
Average daily sunshine Portstewart
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Hrs sunshine 1.5 2.5 3.3 5.4 6.2 5.8 4.6 4.6 3.7 2.8 2 1.2

Day / night temperatures

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

Portstewart average minimum / maximum temperatures (Celsius) Portstewart average minimum / maximum temperatures (Fahrenheit)
Maximum and minimum daily temperatures in Portstewart (degrees centigrade and fahrenheit)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Min °C 1.2 1 2.1 3.4 5.6 8.3 10.2 10 8.5 6.6 3.2 2.1
Max °C 6.6 6.7 8.5 10.9 13.6 16.2 17.3 17.3 15.3 12.7 9 7.4
Min °F 34.1 33.9 35.7 38.1 42 46.9 50.3 49.9 47.3 43.9 37.7 35.8
Max °F 39 39 41.5 44.8 49.2 54.1 56.8 56.5 53.4 49.4 42.9 40.6

Sea temperature

The graph below shows the average sea temperature.

Portstewart average sea temperature chart (Celsius) Portstewart average sea temperature chart (Fahrenheit)
Average sea temperature around Portstewart in degrees centigrade and fahrenheit
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
°C 8.7 7.9 7.8 8.5 10 11.9 13.5 14.3 14 13 11.6 10.1
°F 47.7 46.2 46.1 47.4 50 53.5 56.3 57.8 57.2 55.4 52.8 50.1

Wind speed

The graph below shows the average wind speed.

Portstewart average winspeed by month (km/h) Portstewart average winspeed by month (mph)
Average wind speed in Portstewart (mph and kmh)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
km/h 27 26 26 22 21 19 19 19 22 24 25 26
mph 17 16 16 14 13 12 12 12 14 15 16 16

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.

Portstewart relative humidity averages
Average relative humidity in Portstewart
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
90% 87% 86% 84% 84% 84% 86% 88% 89% 90% 90% 92%

Other monthly averages

UV index Best time to go?

Portstewart weather stats

Portstewart weather statistics
Hottest month: July 17.1°C 62.8°F
Driest month: April 66mm 2.6ins
Sunniest month: May 6.2hrs
Coldest month: January 6.5°C 43.7°F
Wettest month: October 123mm 4.8ins
Warmest sea: August 14.3°C 57.7°F
Map showing location of Portstewart (55.18132, -6.71402) Portstewart map pin © Google

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