
Rail firms have warned of travel chaos for commuters as a 'danger to life' alert forces blanket speed restrictions across the train network and Britain braces for grim weather tonight.

A toxic cocktail of hail, torrential rain and 48 hours of thunder and lightning is set to take hold as forecasters also warn of fast flowing or deep floodwater.

The Met Office has activated weather warnings for rain in southern England, the Midlands and Wales for today, before most of the country is covered tomorrow, while there is also an alert for 'frequent lightning and large hail'.

Up to 3.1in (80mm) of rain in just two to three hours is expected in southern areas of the country today, followed by another 2.4in (60mm) in three hours tomorrow, which could hit almost anywhere across Britain.

Great Western Railway trains are running under a blanket speed restriction, around 50mph, between 4pm today and 6am tomorrow due to the severe forecast, which the operator warned would 'significantly impact' its services.

Passengers should travel 'as early as possible' and 'consider changing your travel plans, as the situation is likely to deteriorate quickly', with services towards Bristol, South Wales, Exeter and the Cotswolds all due to be affected.

And as the bad weather begins to roll in, airlines have started cancelling flights, much to the outcry of passengers who say they are being left stranded at airports and far-flung destinations.

Two people walk through the torrential rain with umbrellas and waterproof coats on Brighton seafront this morning

Visitors at the Bath and West Show in Somerset head for cover as torrential rain strikes the area today

A woman shelters under an umbrella while others use a poncho at the Bath and West Show in Somerset today

People try to make the best of a rainy day in Bournemouth, Dorset, today as the UK is hit by wet conditions

Deckchairs loungers and picnic tables lay empty on a rainy day on Bournemouth seafront in Dorset today

People shelter under umbrellas as they walk alongside puddles on Bournemouth beach in Dorset today

A family shelter under an umbrella at Bournemouth in Dorset today as they make the most of an empty beach

A group of people run for cover as day-trippers try to make the best of a rainy day today in Bournemouth, Dorset

Deckchairs stacked up on an empty Bournemouth beach in Dorset as parts of Britain are hit by heavy rain today

Hail stones the 'size of golf balls' fell in Daventry, leaving one resident with £5,000 worth of damage to his Audi cars

Garden furniture was broken by hail stones which fell in Northamptonshire as a freak storm damaged to cars and gardens

A London bus crosses Waterloo Bridge in a gloomy London this morning, with the financial district in the background

The bad weather follows a week of thunderstorms and flash floods across the UK that have seen half-term getaway plans trashed as dozens of flights were cancelled, rail services were disrupted, roads submerged and properties flooded.

In preparation for the storm, Network Rail said in a statement that due to the weather, track teams would be in key locations and there would be spare parts for signalling equipment available at strategic locations.

Network Rail encouraged customers to check alerts before they travelled in case of any major disruptions to service, as its teams would continue to check drains and culverts in areas prone to flooding.

Passengers flying in and out of Gatwick and Stansted airport have taken to Twitter to complain of long flight delays and sitting on the tarmac for hours on end, with no idea when they will be able to leave.

Ryanair announced on Thursday afternoon that there were a series of delays for flights, as well as a number of flights being cancelled.

In a statement to Mail Online, a Ryanair spokesperson said: 'Due to adverse weather conditions around London Stansted we regret we have been forced to cancel a small number of flights.

'All affected customers have been contacted by email and SMS text message and advised of their options of a full refund, rebooking on to the next available flight or transferring to an alternative flight.

'We apologise for any inconvenience caused by this weather disruption, which is entirely beyond our control, and we are working hard to minimise the disruption to our operations.'

Today, the Environment Agency has imposed 30 'be prepared' flood alerts for England - mostly in the South, including ten within the Greater London area - with its teams working to clear debris from rivers.

The average rainfall in the West Midlands for the entire month of May is 2.2in (55mm), while it is closer to 2.3in (59mm) in parts of the South East, but this could be well beaten both today and tomorrow.

The Met Office expects thunderstorms to affect southern parts of the UK from late this morning through the rest of the day, and has warned flooding of homes and businesses 'could happen quickly'.

There could also be damage to some buildings from floodwater, lightning strikes, hail or strong winds – and fast flowing or deep floodwater is possible, causing a 'danger to life', according to forecasters.

Weather experts have also said spray and sudden flooding could lead to difficult driving conditions and some road closures – and there is a chance of delays to train and bus services where flooding or lightning strikes occur.

The Met Office expects thunderstorms to affect southern parts of the UK from late this morning through the rest of the day

The Met Office has issued amber and yellow weather warnings for rain in parts of Britain today (left) and tomorrow (right)

The intense rainfall expected over parts of England and Wales this evening is shown in this Ventusky graphic

Both the pollen count (left) and ultraviolet radiation levels (right) are high for many parts of England and Wales today

Further rain and thunderstorms are expected tomorrow, although temperatures will hit 72F (22C) in the South East of England

Torrential rain and thunderstorms brought flash flooding to the Bedfordshire market town of Dunstable yesterday

Drivers faced difficult conditions on the M25 in Surrey yesterday as they travelled along the motorway in heavy rain

Lightning strikes over London last Sunday as the capital was hit by severe weather over the bank holiday weekend

Extreme weather in Britain so far this year Britain has faced a series of extreme weather events over the past few months, including: Storm Eleanor batters Britain with 100mph gusts, heavy rain, hail and thunder and lightning (January 3)

batters Britain with 100mph gusts, heavy rain, hail and thunder and lightning Storm Fionn hits western areas with 85mph gusts in the Republic of Ireland and snow (January 16)

hits western areas with 85mph gusts in the Republic of Ireland and snow Storm David brings 93mph wind gusts to North Wales with 100,000 properties without power and rail services disrupted (January 18)

brings 93mph wind gusts to North Wales with 100,000 properties without power and rail services disrupted Storm Georgina brings winds gusting close to 115mph across the Scottish mountains (January 24)

brings winds gusting close to 115mph across the Scottish mountains The Beast from the Eas t and Storm Emma keep daytime temperatures below freezing and leave drivers stranded overnight in heavy snow. Thousands of schools close and isolated communities get supplies via helicopter, in the most significant spell of snow and low temperatures for the UK since 2010 (February 28)

and keep daytime temperatures below freezing and leave drivers stranded overnight in heavy snow. Thousands of schools close and isolated communities get supplies via helicopter, in the most significant spell of snow and low temperatures for the UK since 2010 Britain has its warmest April day since 1949 as temperatures hit 84.4F (29.1C) in London, which is still 2018's warmest day so far (April 19)

as temperatures hit 84.4F (29.1C) in London, which is still 2018's warmest day so far High pressure in the near continent draws very warm air from the south for the hottest early May bank holiday Monday on record with 83.6F (28.7C) in London (May 7)

with 83.6F (28.7C) in London Parts of England are hit by a week of thunderstorms (May 26 – June 1) Advertisement

There are even fears that power cuts might occur and other services to homes and businesses could be lost, while the Met Office is also warning that some communities might become cut off if roads flood.

Forecasters say there is the potential for 1.2in (30mm) to 1.6in (40mm) of rain to fall in an hour and perhaps as much as 2.4in (60mm) to 3.1in (80mm) in two to three hours over the warning area today.

Meanwhile there is a separate rain warning in place from midnight to 9pm tomorrow, with the Met Office warning that thunderstorms are likely to affect southern and western parts of the UK throughout the day.

Forecasters expect thunderstorms across southern England and Wales to move north-west towards Northern Ireland during Friday, which will be replaced by scattered thunderstorms persisting into the early evening.

These are likely to bring further torrential rain to some places tomorrow with the potential for 0.8in (20mm) to 1.2in (30mm) of rain to fall in an hour and perhaps as much as 2.4in (60mm) in a few hours.

Yesterday's highest and lowest UK temperatures were both in the Highlands, with 78.6F (25.9C) at Achnagart, and 39F (3.9C) in Kinbrace. The wettest place was Westonbirt in Gloucestershire with 1in (25.2mm) of rain.

It comes after a man in his 80s died on Monday after he became submerged in flood waters amid a deluge of rain across the West Midlands over the Bank Holiday weekend.

Parts of Birmingham were hit by a month's rainfall in just one hour on Sunday before almost a dozen people had to be rescued from flood-swamped cars in Milton Keynes. Meanwhile the emergency services received 200 calls from those caught in flash floods.

Kent County Council said some rounds had been left 'virtually impassable' with sections of highway drainage system 'overwhelmed' by downpours.

On the M2 drivers faced severe delays after heavy rain resulted in flooding, with Highways England warning the westbound carriageway was closed between Junction 5 and Junction 4. There were also problems on the A249.

And train travellers were handed plastic bags to wear over their feet and legs at Herne Bay station after the tunnel joining platforms 1 and 2 and the surrounding areas were submerged.

Twitter users told of their displeasure at the weather conditions in London this week, with some labelling them 'crazy'

Freak hail stones 'the size of golf balls' hammer down on town causing £5,000 worth of damage to Audi cars Residents were left terrified after hail stones 'the size of golf balls' hammered down with a deafening sound during a freak storm causing thousands of pounds worth of damage to properties. The extreme weather event battered cars and homes in Daventry, Northamptonshire, leaving one resident with more than £5,000 worth of damage to his Audi cars. Shocking video shows huge hail stones raining down in a garden. Edward George, 31, captured the drama in his conservatory, and said one of his Audis was left with £3,000 worth of damage and more than 200 dents to the bodywork. A second Audi received 120 dents and £2,500 worth of damage. He said the hail also punched holes through his garden furniture and dented neighbours' cars along his street. Mr George, who lives with his wife Radka and their two-month-old son, said he had never seen hail stones this big. The engineer said: 'My outdoor furniture has had holes punched through it. Every person's car parked outside has been dented. It was never strong enough to smash a windscreen but enough for a golf ball effect. 'It was torrential rainfall - then all of a sudden it went to heavy hail. It all happened so quickly. I ran into the conservatory to take the video. As soon as I sent it to my friend he asked 'what about the cars?'. They're the biggest hailstones I have seen.' Damage to residents' cars will be covered by insurance companies - but will cut their no claims bonuses. Another neighbour, who did not want to be named, added: 'It was pretty scary, it sounded like the roof was going to come in. 'They were about the size of golf balls and did a right number on my car. Its going to cost a fortune to get the bodywork fixed. You see these sort of things in Australia and places like that - but never here in Britain.' The Tornado and Storm Research Organisation (Torro), a privately supported research body, is investigating the storm and will present findings at its annual autumn conference in October at Oxford Brookes University. Advertisement