Airline passengers breathed a collective sigh of relief yesterday as a gap in the ash cloud from Iceland's latest volcanic eruption allowed almost disruption-free travel.
Seismologists reported that Grimsvotn's eruption had died down, with no ash plume seen since 3am GMT yesterday.
But there were warnings that clouds of ash already in the sky could return to Britain tomorrow in time for the start of any bank-holiday getaways.
Scientists believe the bulk of the ash that spewed out of the volcano over the past three days will rest at heights of between 35,000ft and 50,000ft. Airliners typically cruise between 25,000 and 40,000ft and the hope is that by the time any planes head towards Britain they will be flying lower than any potentially risky cloud formations.
The break in the ash cloud allowed flights to resume after a day of disruption on Tuesday which led to around 500 cancellations across northern Britain. Yesterday a handful of flights were cancelled, mainly to Germany and the Netherlands, where the bulk of the ash cloud is drifting. German authorities were forced to suspend operations out of Bremen, Hamburg and Berlin's two airports yesterday morning. But flights resumed later in the day.
Across Europe, just under 1,000 flights have been disrupted by the Grimsvotn eruption – a fraction of the chaos caused last year when Eyjafjallajokull erupted. More than 10 million people were affected by a six-day European airspace shutdown that followed, with delays costing the airlines up to $1.7bn.
This time the airlines may be luckier. Pall Einarsson, a geophysicist at the University of Iceland, told Reuters: "At this stage we can at least hope for the worst to be over in terms of ash production.
"At the moment there is practically no ash being produced – and what little there is is being deposited on the glacier that is immediately around the crater."
Since the eruption of Eyjafjallajokull, new rules have been brought in to allow airlines to have more say about whether they can fly through ash clouds. Many airlines have run tests to show their aircraft can fly through medium density clouds – classified as having between 2 and 4 grams of ash per 10 cubic metres.