© MetOfficeIncredible satellite images show Storm Dennis - that has exploded into a bomb cyclone - moving in over Britain
Storm Dennis has exploded into a bomb cyclone as meteorologists dub it one of the worst North Atlantic storms ever recorded.
No fewer than 40,000 passengers have been affected by travel disruption so far as budget airline easyJet cancels 234 flights from, to and within the UK as the fourth named storm of the year brings 70mph winds and 100mm of rainfall in some areas from Saturday morning.
Storm Dennis will come as a second blow to flood-ravaged communities still recovering from damage caused by heavy rainfall and 80mph winds brought by Storm Ciara last week.
The last storm - likely the biggest in the century - claimed three victims after a falling tree killed a 58-year-old Mercedes driver, a 77-year-old man fell over and banged his head on ice and a falling branch killed a dog walker in his sixties.
And now, 1,200-mile wide 'Dennis the Menace' is to cause mayhem for towns in Yorkshire's Calder Valley, which was inundated with floodwater when Storm Ciara raged.
The Environmental Agency have warned that due to the water-soaked ground left over by Storm Ciara, the latest flooding is expected to be worse than what has been seen so far, the BBC reports.
© PAYesterday in Mytholmroyd, West Yorkshire, officials were seen desperately trying to prepare for Storm Dennis by using sandbags as flood defences
Storm Dennis became a 'bomb cyclone' on Thursday, when air pressure dropped by 24 millibars within 24 hours.
Remarkably, this is over two times the drop necessary to give the phenomenon its extreme name.
Met Office meteorologist Greg Dewhurst told Glasgow Live: 'On a slightly more technical definition, it's called rapid cyclogenesis. It's a low pressure system which drops 24 milibars in 24 hours or more.
'An easier way to think of it is, it's a low pressure weather system that drops really quickly.'
British Airways has cancelled around 20 to 30 flights due to the storm on top of easyJet's 234.
Frustrated travellers took to Twitter to vent their frustration at their ruined half term plans.
Danny Gearing wrote: 'Supposed to be flying out for weeks skiing tomorrow. Got a text message from easyJet to say flight cancelled. No apology or explanation. Disgusting service.'
Peppard added: 'easyJet your customer service or the lack of it is appalling. We are stuck in Spain with no updates or information from you.'
David Oliver wrote: 'Just to let you know that the comment about doing everything they can to help travellers affected by Storm Dennis is utter rubbish. We had one email from them cancelling flight, then nothing.
'My wife was on hold to their call centre for 3 1/2 hours last night before we gave up. The website is no use whatsoever and there is no where near enough capacity to cope.
'At the moment it also looks like every other airline at Bristol is operating their flights! Flights to Fuerteventura only operate once a week so Half Term ruined!'
While Iceland, will feel the brunt of the bad weather- that could potentially be one of the worst North Atlantic storms on record - the UK will be lashed by high winds and intense rainfall.
Meteorologist Tony Zartman told Accuweather: 'The highest rainfall totals will likely concentrate across Scotland, Wales, Denmark and Norway, which is typical with a windstorm taking this track.'
The Met Office raised the alert to amber for Dartmoor and south Devon, most of Wales, the Pennines and large swathes of Yorkshire - where up to 5.5 inches of rain is expected to fall.
The amber warning area includes towns in West Yorkshire where hundreds of homes were flooded after Storm Ciara brought more than a month's rain last weekend.
In York, where the Ouse peaked at more than 14ft on Tuesday, river levels remained high at nearly 11ft yesterday.
'Homes and businesses are likely to be flooded.
'Fast-flowing or deep flood water is likely, causing danger to life,' the Met Office said.
Storm Dennis is likely to cause gusts of up to 50mph around the country until midday tomorrow, rising to 70mph in southern and western coastal areas.
But last night rail firms had not warned passengers not to travel - unlike during Storm Ciara, which brought gales of up to 97mph.
The amber warning is in place from noon today until 3pm tomorrow and a wider yellow weather warning for heavy rain is in place until 9pm.
This covers southern England, the North West, Wales, Cumbria and the Pennines, with up to two inches of rain forecast.
Storm Dennis will also bring mild temperatures of up to 14C (57F) in southern England this weekend, before returning to cold and blustery weather next week.
Steven Willington, of the Met Office, said: 'There is a risk of significant impacts from flooding, including damage to property and danger to life from fast flowing floodwater.'
Green Flag are expecting a staggering 55,000 callouts over the weekend and 223,800 breakdowns over the half-term period.
A spokesman for British Airways said: 'The majority of our flights are planned to operate as planned, but, like all airlines flying to and from the UK today, we are experiencing some disruption due to the stormy weather conditions.
'We are merging a small number of Heathrow short-haul flights to the same destination and using larger aircraft where possible to minimise disruption.
'Customers can check ba.com for the latest flight information.'
A spokeswoman for easyJet, which has confirmed 234 cancellations, said: 'Due to forecasted adverse weather conditions caused by Storm Dennis, easyJet, like other airlines, is currently seeing disruption to its flight programme for Saturday February 15th.
'We are doing everything possible to minimise the impact of the disruption for our customers and to arrange alternative travel.
'Customers on cancelled flights have been given the option of transferring their flight free of charge or receiving a refund. We will also provide hotel rooms and meals for customers who require them.
'We recommend customers travelling to and from UK today, February 15th, to check the status of their flight and gate information on easyJet's Flight Tracker for latest travel updates.
'Whilst this is outside of our control, we would like to apologise to passengers for any inconvenience experienced as a result of the weather.
'The safety and welfare of our passengers and crew is easyJet's highest priority.'
Yesterday in Mytholmroyd, officials were seen desperately trying to prepare for the storm by using constructing flood defences made of sandbags to prevent further damage.
The Environment Agency said the flood impact from the weather system is likely to be worse than last weekend's Storm Ciara due to rain falling on already saturated ground.
Comment: Storm Ciara latest: Six dead across Europe as hurricane-force winds sweep through the continent
John Curtin, the agency's executive director of flood and coastal risk management, said Cumbria, Lancashire and Yorkshire were the areas he was most 'concerned' about.
'This [storm] could be a step up from what we have seen before,' Mr Curtin said.
'We had a big storm last weekend, [we now have] saturated catchments, snowmelt and rainfall, so it is a perfect storm.'
Rail travel is also set to be disrupted as lines including East Midlands Railway, Gatwick Express, Grand Central, Great Northern, Great Western Railway, Greater Anglia, Heathrow Express and Hull Trains all affected.
This afternoon's meeting at Wincanton has been abandoned with the situation monitored on an ongoing basis at Haydock, Lingfield and Ascot.
Inspections were called at the four meetings in anticipation of Storm Dennis hitting the country.
Rain is forecast almost everywhere on top of already saturated ground which is still recovering from Storm Ciara.
It was all too much for Wincanton, unfortunately, which had been due to stage the Betway Kingway Hurdle, one of the feature races of the season at the track.
Just after 8am Wincanton's Twitter feed posted: 'Racing has been abandoned. Wind gusts have reached upwards of 30mph and are predicted to rise. The back straight is waterlogged, unraceable ground and will not withstand further rainfall predicted.'
Ascot, Haydock and Lingfield were all given the green light from their early morning inspections, however, the situation at all three could change as the day progresses.
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