Weather in August
Temperature
The highest point of temperatures falls in July and August, when the average high-temperature ascends to 21.4°C (70.5°F).Rainfall
In Portsmouth, during August, the rain falls for 6.6 days and regularly aggregates up to 50mm (1.97") of precipitation. In Portsmouth, during the entire year, the rain falls for 103.4 days and collects up to 699mm (27.52") of precipitation.Sea temperature
In August, the average sea temperature is 16.8°C (62.2°F).Note: Swimming in water that is 16.8°C (62.2°F) is not enjoyable for most. Breathing becomes more challenging to manage as the water temperature dips from 21°C (69.8°F) to 15°C (59°F).
Daylight
In Portsmouth, the average length of the day in August is 14h and 29min.On the first day of August, sunrise is at 5:31 am and sunset at 8:49 pm. On the last day of the month, sunrise is at 6:17 am and sunset at 7:51 pm BST.
Sunshine
In August, the average sunshine is 7.8h.UV index
The months with the highest UV index in Portsmouth are May through August, with an average maximum UV index of 6. A UV Index estimate of 6 to 7 represents a high threat to health from exposure to the Sun's UV rays for the average person.Note: In August, a regular UV index of 6 translates into these guidelines:
Act on precautions and pay attention to sun safety recommendations. Avoidance of sunburn is obligatory. Stay out of direct sunlight between 10 a.m. and 4 p.m., when UV radiation is most intense, and remember that not all shade structures provide complete protection. To best shield against UV radiation, choose sun-safe garments and dependable sunglasses.
Frequently asked questions
What part of the year is the hottest in Portsmouth?
What are the temperatures in Portsmouth in August?
How many days does it rain in August in Portsmouth?
How cold is the water in August in Portsmouth?
How many hours of daylight does Portsmouth have in August?
When are sunrise and sunset in August in Portsmouth?
How long on average sun shines in August in Portsmouth?
What are the months with the highest UV index in Portsmouth?
How high is the UV index in August in Portsmouth?
Average temperature in August
Portsmouth, United Kingdom
- Average high temperature in August: 21.4°C
The warmest months (with the highest average high temperature) are July and August (21.4°C).
The months with the lowest average high temperature are January and February (8.2°C).
- Average low temperature in August: 14.3°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 August
Portsmouth, United Kingdom
- Average rainfall in August: 50mm
The wettest month (with the highest rainfall) is October (86.2mm).
The driest month (with the least rainfall) is June (42mm).
Average rainfall days in August
Portsmouth, United Kingdom
- Average rainfall days in August: 6.6 days
The months with the highest number of rainy days are January and December (11.2 days).
The month with the least rainy days is July (5.4 days).
Average sea temperature in August
Portsmouth, United Kingdom
- Average sea temperature in August: 16.8°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 August /
Average sunshine in August
Portsmouth, United Kingdom
- Average daylight in August: 14h and 3min
The month with the longest days is June (Average daylight: 16h and 24min).
The month with the shortest days is December (Average daylight: 8h and 0min).
- Average sunshine in August: 7h and 5min
The month with the most sunshine is July (Average sunshine: 8h and 24min).
The month with the least sunshine is December (Average sunshine: 2h and 0min).
Average UV index in August
Portsmouth, United Kingdom
- Average UV index in August: 6
The months with the highest UV index are May, June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 1).
Portsmouth, United Kingdom
Weather forecast for your location
2. Allow the app to use your location
