Storm Eleanor tears roof off Harland and Wolff factory building

The mammoth mobile building at Harland and Wolff (H&W) Heavy Industries in east Belfast was not in use at the time.

It was intended for painting projects, a spokesman for the company said.

H&W was once one of the world's leading shipbuilders - it built the Titanic - and currently focuses on offshore energy and steel fabrication.

The spokesman said the damage affected the outer skin of the roof.

Tens of thousands of homes and businesses across the island of Ireland lost power overnight as the storm swept in from the west.

Winds of up to 100mph wreaked significant damage and caused flooding on the Atlantic coast.

Met Eireann, the Republic's weather forecaster, issued its second highest level of alert forecast and high waves battered the coastline, causing widespread flooding damage.

Pictures from Galway city centre on Tuesday evening showed cars ploughing through high water and business owners struggling to protect their properties.

Rescuers waded through knee-high water.

One car bobbed in the high coastal waters and drivers attempted to reach safe ground.

Flooding also hit Salthill, Oranmore and Clarinbridge as high tides combined with gale-force winds.

Some cars were abandoned in Oranmore as roads were blocked while others in a car park in Salthill were partially submerged.

A meeting of Ireland's National Emergency Co-ordination Group was due on Wednesday morning.

At least 55,000 properties experienced blackouts overnight as the winter storm damaged the network.

A statement from power supply company ESB said: "The number of customers out now stands at 27,000, with 10,000 of those customers in Mayo, the worst impacted county.

"ESB Networks teams have now restored power to 123,000 customers, and are working in difficult conditions to get the remaining customers still without power back by tonight.

"Crews in less impacted areas are on the move this morning to the worst impacted counties."

ESB Networks said counties worst affected in the Republic included Galway, Mayo, Sligo, Leitrim, Cavan and Monaghan.

In Galway, streets around the docks were flooded after high tides breached defences and inundated the areas around the Spanish Arch, Claddagh, Dominick Street and Quay Street.

Water was more than 1ft deep in places.

The Coast Road from the city to Oranmore was also impassable at rush hour on Tuesday as high tide combined with the strong winds to cause local flooding.

In Gort, Co Galway, households were warned about potential disruption to water supplies after power cuts hit the local pumping station.

There were also reports of spot flooding on the N85 Ennis to Ennistymon road in Co Clare.

Across the island, fallen trees forced road closures.

In Northern Ireland more than 20,000 customers, mainly across the border counties, were left without power at the height of the gales.

There were 400 separate incidents of damage to the electricity network.

Engineers worked through the night to restore power to thousands of customers.

A Met Office yellow wind warning affecting all of Northern Ireland was due to lift at 6pm.

Julia Carson, NIE Networks communications manager, said repairs were progressing well.

"The damage caused by Storm Eleanor includes power lines brought down by falling trees and poles broken by the high winds.

"We have been working in difficult conditions since yesterday evening to restore power to over 20,000 customers and we'll continue to respond to reports of damage and reconnect supplies as quickly and safely as possible."

Emergency teams from northern counties are helping restore power in areas where the network was damaged by Storm Eleanor.