August weather forecastCalais, Guernsey
August
Weather in August
Following July's heat, August sees a slight rise in temperature to an average high of 17.8°C (64°F). Humidity levels hit a little high at 82%, but the weather remains comfortable due to a refreshing sea breeze blowing at 34.3km/h (21.3mph) gusts. The daylight hours decrease slightly from 15.8 hours in July to 14.4 hours. Meanwhile, the city witnesses a surge in precipitation with 41mm (1.61") of rain spread across 14 days, indicating intermittent rainy spells. Despite these conditions, Calais continues to lure many for its summer charm, making August one of the most popular months for visiting.Temperature
The average temperatures reach their apex in August, averaging 17.8°C (64°F) at the high end and 15.8°C (60.4°F) at the low end.Humidity
The average relative humidity in August is 82%.Rainfall
In Calais, in August, it is raining for 14 days, with typically 41mm (1.61") of accumulated precipitation. In Calais, during the entire year, the rain falls for 196.3 days and collects up to 557mm (21.93") of precipitation.Snowfall
In Calais, Guernsey, snow does not fall in February through December.Daylight
In August, the average length of the day in Calais is 14h and 22min.On the first day of the month, sunrise is at 05:42 and sunset at 20:50. On the last day of August, in Calais, sunrise is at 06:25 and sunset at 19:55 BST.
Sunshine
In August, the average sunshine in Calais is 9.2h.UV index
July through September, with an average maximum UV index of 5, are months with the highest UV index. A UV Index reading of 3 to 5 represents a medium health hazard from unsafe exposure to UV radiation for ordinary individuals.Note: The UV index of 5 during August translates into the following guidance:
Be mindful. Those with pale skin might receive burns in fewer than 30 minutes. The best time to avoid the Sun's harmful UV radiation is during midday when it's most potent. A wide-brimmed hat is a staple for defending the face, eyes, ears, and neck from the Sun.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in August
Calais, Guernsey
- Average high temperature in August: 17.8°C
The warmest month (with the highest average high temperature) is August (17.8°C).
The month with the lowest average high temperature is February (9.2°C).
- Average low temperature in August: 15.8°C
The month with the highest average low temperature is August (15.8°C).
The coldest month (with the lowest average low temperature) is February (7°C).
Average pressure in August
Calais, Guernsey
- Average pressure in August: 1016.4mbar
The month with the highest atmospheric pressure is September (1017.9mbar).
The month with the lowest atmospheric pressure is November (1011.5mbar).
Average wind speed in August
Calais, Guernsey
- Average wind speed in August: 22.8km/h
The windiest month (with the highest average wind speed) is December (36km/h).
The calmest month (with the lowest average wind speed) is July (21.9km/h).
Average humidity in August
Calais, Guernsey
- Average humidity in August: 82%
The months with the highest relative humidity are June and July (84%).
The months with the lowest relative humidity are November and December (77%).
Average rainfall in August
Calais, Guernsey
- Average rainfall in August: 41mm
The wettest month (with the highest rainfall) is November (87mm).
The driest month (with the least rainfall) is July (26mm).
Average rainfall days in August
Calais, Guernsey
- Average rainfall days in August: 14 days
The month with the highest number of rainy days is November (22.8 days).
The month with the least rainy days is June (11.5 days).
Average snowfall in August
Calais, Guernsey
- Average snowfall in August: 0mm
The month with the highest snowfall is January (2mm).
The months with the least snowfall are February, March, April, May, June, July, August, September, October, November and December (0mm).
Average snowfall days in August
Calais, Guernsey
- Average snowfall days in August: 0 days
The month with the highest number of snowfall days is January (0.3 days).
The months with the least snowfall days are March, April, May, June, July, August, September, October, November and December (0 days).
Average daylight in August /
Average sunshine in August
Calais, Guernsey
- Average daylight in August: 14h and 24min
The month with the longest days is June (Average daylight: 16h and 12min).
The month with the shortest days is December (Average daylight: 8h and 18min).
- Average sunshine in August: 9h and 12min
The month with the most sunshine is July (Average sunshine: 9h and 42min).
The months with the least sunshine are January, November and December (Average sunshine: 3h and 54min).
Average sunshine days in August
Calais, Guernsey
- Average sunshine days in August: 12.1 days
The month with the most sunshine days is May (16.3 days).
The month with the least sunshine days is November (4 days).
Average UV index in August
Calais, Guernsey
- Average UV index in August: 5
The months with the highest UV index are July, August and September (UV index 5).
The month with the lowest UV index is February (UV index 2).
Average cloud cover in August
Calais, Guernsey
- Average cloud cover in August: 40
The months with the most cloud cover are November and December (Cloud cover 63).
The month with the least cloud cover is July (Cloud cover 37).
Average visibility in August
Calais, Guernsey
- Average visibility in August: 10km
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (10km).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (10km).





