Heathrow to have busiest Whitsun bank holiday for 10 years with New York, Dubai and Dublin top three destinations More than 2 million people are expected to pass through UK airports this weekend as travellers start the half-term getaway. Heathrow will have its busiest Whitsun bank holiday for at least 10 years with New York, Dubai and Dublin the top three destinations for its expected 800,000 passengers. The Grimsvötn volcano in Iceland remained active on Thursday but was spewing out steam and smoke rather than the ash particles that grounded 900 flights in northern Europe at the start of the week, threatening a repeat of last year’s volcano crisis, when 100,000 flights were cancelled. Eurocontrol, the continent’s air traffic control body, said it expected a trouble-free weekend. “Any significant ash concentrations are far out over the sea, at very low altitudes and well away from the air routes or airports,” said Eurocontrol’s head of network operations, Brian Flynn. “The expectation for the next couple of days is that there will be no disturbances to air traffic whatsoever.” However, the UK’s unusual bank holiday luck this year seems certain to run out over the weekend, with cool and showery weather forecast until well into next week. In place of the sunlit Easter period, when temperatures topped 28C (82F), and the warmth over the royal wedding and May Day, much of the country will be lucky to manage more than 16C (61F). Barry Gromett at the Meteorological Office settled on a theme of “clouds and cloudiness” with only isolated periods of sunshine, mainly in the south-east. He said: “It looks like being a mixed bag, with plenty of outbreaks of rain.” Downpours will not match those on Thursday which delayed the start of the England and Sri Lanka Test cricket match at Cardiff until 3.30pm. There were also heavy falls in London and the Midlands, much to the relief of gardeners and water companies after a prolonged dry period. The AA says 15m cars will hit the roads with traffic building from Friday afternoon. It warned of particularly busy roads between 10am and 2pm on Saturday, with less congestion on Sunday and bank holiday Monday. According to Trafficmaster, the top five traffic hotspots will be: the A303 through Hampshire, Wiltshire and Somerset; the M5 from Bristol to Exeter; the M3, M27 and A31 between Winchester and the Dorset coast; the M6 north of Birmingham to Lancashire; and the westbound M25 between junctions 21 and 12. The AA warned that motorists could be caught out by high fuel prices because a £40 purchase at the pump will cover less distance than it did last year. Edmund King, AA president, said: “There are too many drivers out there running on fumes and the AA has experienced an 18% increase in call-outs call to drivers running on empty.” The Icelandic ash plume will bring an unexpected benefit to rail passengers travelling between London and Glasgow after Network Rail lifted engineering works on the west coast main line amid fears that Grimsvötn would erupt over the weekend. The works will not be reinstated. “We are just doing our bit,” said a Network Rail spokesman. More than 5 million rail passengers are expected to travel on the network this weekend. The major engineering works are at Liverpool Street station in London, where there will be no trains to Shenfield on Sunday and Monday. South London between London Bridge and Victoria and Tulse Hill will also be affected. Air transport Dan Milmo Martin Wainwright guardian.co.uk