Temperatures hit 32.7C on hottest day of the year so far
The UK could have a record six days of 30C heat for the first time in September
Saturday is provisionally the hottest day of the year so far, with 32.7C recorded in Heathrow.
The UK has now sweltered through six days of temperatures above 30C in September for the first time.
But thunderstorms could spoil further spells of warm weather generated by the record heatwave this weekend, the Met Office has said.
Saturday was the sixth day in a row when temperatures topped 30C, according to the forecaster, but there is an increasing chance of some intense thundery downpours developing in central and western areas.
Thursday was previously the hottest day of the year so far, with 32.6C recorded in Wisley, Surrey.
The warm weather will continue into the weekend - especially in the south-east - but sporadic thunderstorms could spoil the party by bringing heavy showers and even hail for some, the Met Office said.
Spokesman Stephen Dixon had previously said a secondary temperature peak could happen on Saturday.
He said: "For most people it will still be a dry and fine Saturday and temperatures will remain high. The south and east of the country will probably hold on to the hot weather the longest.
"But we have issued a yellow weather warning for thunderstorms on Saturday afternoon for central England and eastern Wales.
"Some might see 30-50mm of rain; there's a possibility of hail and lightning. Not everyone will see these showers; they'll pop up here and there.
"There's a bit of a weather breakdown on the way. Some might see thundery rain but it will stay hot.
"On Sunday, the hot weather will be more confined to the south and east.
"Elsewhere, it will become more unsettled and temperatures will return to the high teens.
"There is a continued chance of further warnings as we monitor the weather."
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