An Arctic chill blowing in from the North Sea promises temperatures no higher than 10C across England and Wales. Scotland has been warned to brace itself for wintry showers.
Today's weather is expected to start cold and frosty, with showers developing to put a damper on outdoor activities.
The outlook for tomorrow and Monday is slightly more optimistic, with rain in the North and bright and mainly dry weather in the South. It will stay chilly.
With weather like that to look forward to, about 250,000 British sunseekers fled yesterday for foreign hotspots.
For those stuck at home, motoring organisations warned of serious congestion over the weekend even though cones have been removed and roadworks suspended on many main routes.
"With the weather so unpleasant there has been a last-minute rush to head off somewhere warmer this weekend," said Keith Betton, head of corporate affairs at the Association of British Travel Agents. "Spain and Portugal are favourite destinations and many people are also taking a city break, with Paris, Amsterdam, Venice and Rome popular."
The ferry company Stena said it was carrying about 100,000 passengers on its continental routes and about 50,000 on its Irish Sea crossings, while the AA said it expected nearly 5 million drivers to hit the road over the Bank Holiday weekend.
Last year's May Day weekend, which featured celebrations for the 50th anniversary of VE Day, was marked by temperatures of up to 28C (82F).
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