The UK is twice as likely as usual to have a hot summer this year, the Met Office has predicted, warning that there is also an increased risk of heatwaves.
The predictions follow the country’s sunniest spring on record, with the UK clocking up 630 hours of sunshine since the start of March, in what has also been the driest spring for more than a century.
Temperatures soared to 8C above the average for the time of year on Saturday – the last day of meteorological spring – before a potentially hot summer season.
Heathrow, in west London, experienced the hottest weather on Saturday, at 26.7C, while levels of grass pollen were very high in the south-east of England.
The Met Office said: “While the current three-month outlook shows an increased chance of a hot summer, the temperature signals for this summer are similar to those for recent years and consistent with our warming climate.”
The predictions come from the Met Office’s three-month outlook for June, July and August, which provides risk assessments for unusual temperatures, rainfall and wind for government contingency planners and businesses. It is based on an assessment of broad weather patterns across the whole of the UK and factors in recent global weather trends.
Nicola Maxey, a spokesperson for the Met Office, said: “It’s not produced as a public forecast for people to look at and work out whether we can have a barbecue in August or a garden party in July.
“At this time of year, global signals influencing UK weather are typically weak,” she added. “However, consistent with our warming climate and as we have seen over recent years, the current outlook indicates an increased likelihood of above-average temperatures this summer. This is not a guarantee of prolonged hot weather or heatwaves; while we could see more hot days and warm nights than usual, we could also see a mix of cooler days and less extreme warmth.”
The outlook shows it is 2.3 times more likely than normal that the UK will be hot over meteorological summer, which begins on 1 June and ends on 31 August. The average temperatures across the UK over those months range from 10-17C, with the south-east of England experiencing the higher averages of 16-17C.
This would be in line with a recent trend of unusually hot summers. The last time the UK experienced a “cool” summer was in 2015.
The ongoing extreme marine heatwave in north-west European waters – sea surface temperatures around UK coastlines are 1.5-2.5C warmer than average – may further boost temperatures, although the added warmth and moisture in the air could potentially lead to more intense summer storms.
The latest outlook also shows the levels of rainfall and wind speed for the next three months are likely to be near average. Many water companies will be hoping for a wet summer to help avoid the need for water usage restrictions. This week, the Environment Agency declared drought status for the north-west of England following the driest start to spring in 69 years, with many reservoirs in the region at historical low levels for the time of year.
Summers in the UK have become warmer, wetter and sunnier in recent decades due to climate change, according to the Met Office’s State of the UK Climate report.
Observations show that extremes of temperature in the UK have been affected much more than average temperature. The number of “hot” days (28C) more than doubled and “very hot” days (30C) more than tripled for 2014-23 compared with 1961-90. Extreme weather events such as the 2022 heatwave, when temperatures in England surpassed 40C for the first time, were made more likely by climate change and are expected to become more common in future.
