Temperature were expected to rise to a high of 21ÚC (70ÚF) in eastern England, with warmer-than-average conditions in the south and south-east. The figures compare with temperatures of 18ÚC or 19ÚC in northern and coastal areas of Greece.
The rest of the UK was cooler and unsettled in some areas with Northern Ireland failing to reach double figures and outbreaks of rain in western Scotland.
Nick Prebble, meteorologist at MeteoGroup, warned yesterday could be the last chance to have a barbecue for the next few days as the weather deteriorates. The Bank Holiday was probably going to prove the warmest day of the week for many.
"There is fairly patchy rain, with some heavier bursts moving into western Scotland at the moment," he said last night. "I think today will be the last of the completely dry weather so far in some areas.
"It is going to be unsettled with showers and longer bursts of rain. It is going to be quite changeable."
A Met Office spokesman said rain overnight would be followed by a fine day today with many areas enjoying bright and fairly sunny conditions.