Northern Ireland has escaped most of the monsoon weather which plunged Dublin into chaos yesterday, causing millions of euros worth of damage.

Almost 40mm — the equivalent of 15 days of rain — fell in just one hour causing devastation throughout the Irish capital.

Part of the roof at the Mater Hospital in the north of the city collapsed forcing the evacuation of 25 patients.

Elsewhere in Dublin 20 people had to be rescued after they became stranded by the torrential downpour and dozens of residents had to be evacuated from their homes.

Heavy rain also fell over much of Northern Ireland yesterday causing havoc on the roads.

Barry Gromett from the Met Office said he would be surprised if the same amount of rain fell in Belfast overnight.

However he was not ruling out the rain altogether.

“Looking ahead to Friday there is a fairly active band of showers,” he said. “It’s quite possible that it will bring some heavy showers around breakfast time. But it is moving relatively quickly. If there are any heavy showers they will be relatively shortlived and will hopefully not lead to many problems.”

But the forecast for the |weekend was predicted to be much bleaker.

Heavy showers are expected to fall on both tomorrow and Sunday with temperatures dropping.

Gromett added the forecast for next week was also poor.

“They show a return to winds from the north or north-west so temperatures are going to take a tumble to more normal levels. Anywhere between mid to high teens. There are quite a lot of showers around next week too.”

Meanwhile, as a huge mopping-up operation got into full swing in Dublin, insurers were beginning to receive their first claims for flood damage.

As the deluge hit the city in the early hours of the morning patients at the Mater had to be moved to different wards following a partial roof collapse in St Camillus' Ward on the top floor of the old hospital building.

For residents of one housing estate in North Dublin it was a repeat nightmare after flood waters swept through their homes for the second time in a year.

Homeowners in Clanmoyle Road, Donnycarney, counted the cost of the flash flooding that surged through their homes, destroying furniture and fittings and flattening garden walls.

A two foot ‘tide’ mark could be clearly seen along buildings as council workmen pumped out water from up to a dozen homes.

Only last August, residents whose semi-detached homes sit over sub-basements, faced a similar disaster and had replaced flooring and furniture only to see them ruined again yesterday.

Residents along Sherrard Street in the north of the city also got a rude early morning awakening as floodwaters poured into their flats.

People had to be evacuated and brought to the Civil Defence headquarters at Collins Barracks where they stayed until the floodwaters subsided in their homes.

A Dublin Fire Brigade spokeswoman said it received 350 calls between 12am and 9am, most of which related to flooding.

Fire crews across the city worked flat-out overnight to pump water, with reports of flooded roads coming in from 2.30am — just half an hour after the |downpour started.