Temperatures reached 29.1C in the village of Hawarden in Flintshire, the Met Office said, but the warm weather is not set to last.
Enjoying the sunshine at Langland Bay(Image: John Myers)
Wales has broken records for its hottest August bank holiday Monday ever. The mercury climbed to 29.1C in Hawarden, Flintshire. The previous Welsh record stood at 26.5C from 1991.
Northern Ireland also recorded its hottest ever August Bank Holiday Monday with 24.5 in Magilligan, Londonderry, well above its previous high of 23.8C. Less settled weather is on the way for Wales though with the remnants of Hurricane Erin about to descend, bringing rain.
Scotland, despite not observing the bank holiday, also witnessed a record for the corresponding day with 27.1C logged at Charterhall.
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However, by later tonight, what remains of Hurricane Erin will deliver rain and gusts to western areas, continuing through the week, forecasters warned.
Met Office meteorologist Marco Petagna said: “It’s going to become breezy, and we’ll see a band of rain pushing eastwards across the UK tonight, clearing east and south-east England tomorrow morning.
“So the first significant rain for many areas for some time.
“Thereafter, it stays more unsettled for the rest of the coming week, with showers, or longer spells of rain, temperatures returning to average and breezy at times as well.”
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Mr Petagna didn’t anticipate any weather warnings being issued during the forthcoming week.
Throughout the remainder of the week, temperatures will sit closer to typical levels, with low 20s expected in southern regions and high teens across northern areas.
Thousands flocked to beaches across Wales. Elsewhere crowds sweltered at London’s Notting Hill Carnival with temperatures hitting 26C, far cooler than the hottest part of Wales though.
In Gloucestershire squads participated in the yearly Football In The River match in Bourton-on-the-Water.