Storm Brian has hit the UK as 70mph winds close roads and cause severe delays on the railways.

Gusts of 70mph have struck the Welsh coast and gusts are set to increase in speed through today.

Forecasters warned of the potential for power cuts, flooding and delays to transport, as families begin their half-term holidays.

The Met Office issued a yellow weather warning for winds across a swathe of Britain, including Wales and southern England up to the Midlands, which will remain in place until midnight on Saturday.

Arriva Trains Wales reported severe delays on many services and roads have been shut in some coastal areas, including Pembrokeshire, reports Wales Online.

Huge waves crash into a harbour wall in Portcawl, south Wales (
Image:
WALES NEWS SERVICE)
The Cornish coast is battered by the tide (
Image:
PA)
Waves were so strong they moved cars along a coastal road in Aberystwyth (
Image:
WalesOnline WS)
The coast of Dorset was among the hardest hit ares of the UK (
Image:
REX/Shutterstock)
A lighthouse in Newhaven, East Sussex, is dwarfed (
Image:
AFP)

Strong winds also hit southern and south-western parts of Ireland on Saturday morning - just a week after Britain and Ireland were battered by the aftermath of Hurricane Ophelia.

Met Office forecaster Craig Snell said: "Unfortunately, across Ireland it's the areas that were worst hit by Ophelia seeing the worst effects of Brian as well."

A massive wave hits the shore in Lyme Regis, Dorset (
Image:
REX/Shutterstock)
The coast of Devon takes a beating (
Image:
REX/Shutterstock)
Severe flooding in Limerick, Ireland (
Image:
Limerick Council/Twitter)
A dog walker watches waves crash into Brighton beach (
Image:
David Sims/WENN.com)

People have been advised to stay away from exposed coastal areas and urged not to take so-called "storm selfies" as high tides and a storm surge create dangerous conditions along some coasts.

The Environment Agency has issued 44 flood alerts, as well as six flood warnings urging "immediate action".

Video Loading
A BMW is covered by a giant wave in Devon (
Image:
REX/Shutterstock)
The harbour master's office in Tenby, Wales, was partially destroyed (
Image:
REUTERS)
People are being urged not to take storm selfies due to the safety risks (
Image:
David Sims/WENN.com)

Ben Lukey, national flood duty manager for the Environment Agency, warned members of the public against posing for photos during the hazardous conditions.

He said: "Environment Agency teams are on the ground, checking defences and taking precautionary action to close tidal gates and put up temporary barriers.

A satellite image showing the path of Storm Brian approaching the British Isles (
Image:
Atlas Photo Archive/NASA)
A small ship struggles with the winds in Dartmouth harbour (
Image:
Andy Kyle / SWNS.com)

"We're working with the Met Office and local authorities and are ready to respond as necessary.

"We urge people to stay safe along the coast and warn against putting yourself in unnecessary danger by taking 'storm selfies' or driving through flood water - just 30cm is enough to move your car."

Cars were covered in sea foam during Storm Ophelia just a week ago (
Image:
Getty Images Europe)
Large waves crashed along sea defences as storm Ophelia approached Cornwall on Monday (
Image:
REUTERS)
Video Loading

National Rail warned the stormy weather could impact on train services, with emergency speed restrictions imposed on most of the routes in Wales.

A spokesman said: "Fallen trees and other debris may temporarily block railway lines and damage overhead wires.

"Speed restrictions may be imposed in the worst-affected areas for safety reasons, which may delay your journey."

Sandbags are deployed in the fight against floodwaters in Galway, Ireland (
Image:
PA)
Men struggle to keep their footing amid gusts during storm Ophelia on the wall of East Pier in Howth, Dublin (
Image:
PA)

Drivers were also urged to take extra care on the roads during high winds, as vehicle recovery and the AA reminded motorists that surface spray, reduced visibility and potential flooding remained high risks.

The Energy Networks Association, representing the UK's energy infrastructure, said residents could call the free 105 advice telephone number in case of damage to local network and power supplies.

Storm Brian is the result of a "weather bomb" of low pressure in the Atlantic Ocean.

It follows Storm Aileen, the first UK-named storm of the season, which left thousands of homes without power last month.