The island announced over the weekend that Jersey Met is adopting the same definition of a heatwave as its UK counterpart.
The UK Met Office states that if the maximum temperature passes 28°C for three consecutive days, a heatwave will officially be in progress.
Guernsey has used this definition for some time already with the local Met Office saying: “We have been using the World Meteorological Organisations (WMO) definition of heatwave as three consecutive days, or more, above a local threshold for a number of years now. In our case we use 28°C or more which is the criteria Jersey Met will now be using too.”
Jersey’s decision to start following the same methodology was confirmed by Paul Aked, the island’s Head of Meteorology.
“We’ve talked about this since last summer’s high temperatures, and believe that bringing us in line with the UK results in a better and simpler system.”
Jersey claims to have seen maximum temperatures just short of the new heatwave threshold over the past week, but on Saturday Mr Aked said there was no current indication of maximum temperatures passing 28°C over the next six days.
Guernsey is also not forecast to go above that temperature this week meaning we shouldn’t hit a heatwave either. However, forecasts for the Bailiwick of Guernsey are issued by the Jersey Met Office – with the Guernsey Met Office collating the data locally on which forecasts are based.
The Jersey Met forecasts our highest temperature for the coming week as 25c on Saturday 24 June. Jersey is forecast to reach 27c on the same day.
Once again, dear neighbours, I must apologize for stealing your sunshine!
— Christopher Beaumont (@SeigneurOfSark) June 18, 2023
Sark is not forecast to go above 20c this week but while Jersey may be able to prove it is bathed in hotter temperatures, the Seigneur is robustly disputing any suggestion that it is sunnier than Sark.
“Being that much bigger there is time for air temperature to build on Jersey (or Guernsey) where it simply doesn’t get the chance to do so over here.
“So, despite our sunnier disposition our temperatures will always be more reasonable than yours. I bet the converse is true in the winter too.
“It is also worth mentioning that we are the tallest island and we have sheer cliffs all round. This is in our favour during times of sea mist. Sometimes mist makes it to the top of the island but mostly it burns off as it’s pushed upwards (or simply does round the sides!).”
I can hear Guernsey’s fog horn in the distance and yet this it what it’s like over here! I think we all know why that is pic.twitter.com/QN9iJHBZNP
— Christopher Beaumont (@SeigneurOfSark) June 12, 2023
HOT STATS…
The hottest year on record in Guernsey was last year with the temperature climbing above 30c on five days during July and August 2022.
It reached 34.2c in Guernsey on 18 July 2022 – making it the island’s second hottest day on record. The hottest day since Guernsey Met Office records began in 1947, was 9 August 2003, at 34.3°C.
The observatory in Sark recorded 34.6°C on 18 July 2022 – the island’s hottest temperature for more than 20 years (since records began). This also made it the hottest day in the Bailiwick on record.
However, Jersey recorded 37.9c on 18 July 2022 making it the hottest day on record there and arguably the hottest day on record in the Channel Islands.
Some parts of the UK reached 40c on the same date.
Read more…
Jersey claims sunniest title…again
Guernsey enjoys its second warmest year on record
Guernsey experiences hottest year
2018 weather stats prove it was a pretty good year