The balmy spring weather is expected to continue past Bank Holiday Monday with temperatures tipped to reach 23C on Tuesday, according to the Met Office.
Forecaster Helen Chivers of the Met Office tells AOL Travel: "The weather is set to turn cooler and more unsettled across the whole of the UK over the next couple of days, but not until after many of us - including Scotland and Northern Ireland who had rather cloudy skies and some rain in places today - have another fine and warm day tomorrow (Tuesday).
"There will be plenty of sunshine around on Tuesday and temperatures will again be in the low 20s Celsius. The highest temperatures may be on a par with the highest we have seen so far this year, reaching 23 Celsius in some central and eastern areas of England."
But the hot and sunny weather won't last as clouds and rain are expected for the rest of the week.
Helen added: "We will see some showers breaking out during the afternoon and evening of Tuesday, and on Wednesday we can expect to see cloud and rain spreading northeast across the UK.
"The rest of the week then looks set to be changeable with bands of cloud and rain moving across the country from the west. The wettest and windiest weather will be in northern and western parts of the UK while southern and eastern areas see the best of the dry, bright spells. Temperatures back to normal for the time of year - in the mid teens by day."
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