Britain has experienced the highest October temperature on record with Gravesend in Kent feeling the heat at 29.9C.
The previous record of 29.4C was set in Cambridge in 1985.
It is the second day of record breaking weather.
On Friday, temperatures of 29C set a new high for the end of September.
Train companies said they were expecting 25% more passengers as people head to the coast to take advantage of the sunshine.
Officials in Brighton, where sunbathers had packed the beach, reported huge increases in visitor information inquiries.
Tourism councillor Geoffrey Bowden said the weather was a "welcome fillip" for the area which relies heavily on income from visitors.
The Royal Horticultural Society said the unexpected warmth had seen plants blooming which they hadn't expected to see again before next spring.
However the good weather has not reached everyone with reports of rain in Belfast.
After Saturday's expected peak, Sunday will be slightly cooler across England but temperatures are still likely to reach 26 or 27C.
Ireland, southern Scotland and northern England may even see some patchy rain.
Monday should remain warm, with temperatures starting to return to the expected levels for this time of year on Tuesday.
The previous record of 29.4C was set in Cambridge in 1985.
It is the second day of record breaking weather.
On Friday, temperatures of 29C set a new high for the end of September.
Train companies said they were expecting 25% more passengers as people head to the coast to take advantage of the sunshine.
Officials in Brighton, where sunbathers had packed the beach, reported huge increases in visitor information inquiries.
Tourism councillor Geoffrey Bowden said the weather was a "welcome fillip" for the area which relies heavily on income from visitors.
The Royal Horticultural Society said the unexpected warmth had seen plants blooming which they hadn't expected to see again before next spring.
However the good weather has not reached everyone with reports of rain in Belfast.
After Saturday's expected peak, Sunday will be slightly cooler across England but temperatures are still likely to reach 26 or 27C.
Ireland, southern Scotland and northern England may even see some patchy rain.
Monday should remain warm, with temperatures starting to return to the expected levels for this time of year on Tuesday.
