This summer in Guernsey was the second warmest on record.
Guernsey Met says the average temperature for June, July and August was 17.8 Celsius, compared to the thirty-year average of 16.2 Celsius.
The hottest day came on 30 June, at 30.4 Celsius.
Summer 2025 in Guernsey - 2nd warmest summer since records began in 1843. pic.twitter.com/bijIdtUhuA
— Guernsey Met (@GuernseyMet) September 3, 2025
It was also the third driest summer of the past 25 years, with less than a third of the rain we'd expect during the month of August.
Sea temperatures - measured in Jersey - were the second warmest since those records began in 1960.
August 2025 in Guernsey - 10th warmest August on record. pic.twitter.com/4qtLAzyiYh
— Guernsey Met (@GuernseyMet) September 3, 2025

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