JERSEY’S meteorological summer ended in fitting fashion yesterday – with rain, cloud, mist and very average temperatures.
But although many Islanders are now heading into autumn with the feeling that summer never began, statistically speaking, it wasn’t really that bad.
Thanks to a very hot June, and lots of cloud during July and August which helped to keep night-time temperatures up, the summer of 2023 was, overall, actually a little warmer than average.
And although it was wet, it was only slightly duller than the seasonal norm.
According to provisional figures released yesterday by Jersey Met, the three-month period defined as meteorological summer – 1 June to 31 August – had an average temperature of 18.1°C, compared to a long-term average of 17.7°C.
There were about 783 hours of sunshine – only slightly less than the average of 787 hours.
But it was much wetter than normal, with about 200mm of rain falling across the three months – about half of it being deposited during a very soggy August – compared to a long-term average of 158mm.
It is likely to have been the wettest summer since 2015.
The culprit was the jet stream – a band of winds high up in the atmosphere which drives low-pressure systems across the Atlantic.
Usually during the summer, the jet moves north, taking the low pressures with it and leaving Jersey on its warmer southern side.
But this year the jet became fixed in a meandering position, with the British Isles and parts of northern Europe stuck in a trough to its cooler northern side, with low-pressure systems dominating the weather.
It was all in stark contrast to last summer – when the Island sweltered in record-breaking temperatures and conditions so dry that Jersey Water had to turn on the desalination plant.
Matt Winter, senior meteorologist manager, said: ‘The stats for the summer as a whole have been pulled upwards by the excess heat we had during June. But the period when the children were off was pretty cloudy and often quite wet.’
He added: ‘Of course, this was in contrast to last summer, when it was very dry and we had record temperatures. Summers like that live on in the memory and it is easy to strike comparisons between the two.’
Next week – the first full week of meteorological autumn and when the school holidays come to an end – Jersey looks set to be blessed with some proper summer weather.
Temperatures are forecast to hit the mid-20s as warm air is pulled in from the continent on easterly winds.
