The Met Office has forecast that Wales will experience its third heatwave of the year, with temperatures climbing above 30°C in some areas. While milder than the June heatwave that saw Cardiff reach 36°C, this week's heatwave is expected to last until the week commencing July 13.
Forecast Details
The Met Office predicts "dry and hot" weather with "some strong sunshine and light winds." Unlike previous heatwaves that lasted over four days, this one is expected to persist into next week. Weather maps show temperatures rising from Monday, July 6, peaking on Friday, July 10.
Monday will see mid-20s temperatures, with the Met Office stating: "Patchy low cloud will linger at first across Wales, but skies will gradually brighten through the morning. Some very warm and hazy spells of sunshine will develop with light winds. Maximum temperature 26 °C." Tuesday will be similar, with sunny spells and light winds, reaching 26°C.
Marine Heatwave
Alongside the land heatwave, a long-lasting UK marine heatwave is likely to reach extreme levels, with surface water temperatures reaching +4-5°C above usual in offshore parts of the Welsh coast. Dr Ségolène Berthou, air-sea interaction specialist at the Met Office, said: "Marine heatwaves around the UK have developed rapidly following the recent heat dome, and we are now seeing widespread strong to locally severe conditions. This is the third and most intense marine heatwave we have seen this year."
She added: "While these warmer seas did not significantly increase peak temperatures on land, they reduced night-time cooling and helped sustain warmth, particularly in coastal areas." Evening and night-time temperatures are expected to remain warm across Wales as the heatwave progresses.
Peak Temperatures and Thunderstorm Risk
Wednesday and Thursday will see temperatures rise further, with Friday being the warmest day, hitting 31°C in areas including Cardiff. Forecasters warn of a potential thunderstorm risk due to the hot weather. Over the weekend, thunderstorms are expected after the high temperatures. The Met Office says: "Dry and very warm weather across England and Wales, but always with an ongoing chance of thunderstorms moving in from France."
Looking ahead to next week, temperatures will continue to be "widely very warm, hot or even very hot in parts of the south," but there are signs that the heatwave may begin to ease from Monday, July 13.
