More than 120 people had to be rescued in Northern Ireland after being trapped by overnight flooding.
The north west was worst affected, particularly Londonderry, as well as other parts of the county and Tyrone.
Firefighters rescued 93 people who were trapped by flood water in their cars or homes. At one point, the fire service got an emergency call every 45 seconds.
The Met Office confirmed that 63% of the average August rainfall fell within a 8-9 hours period.
The coastguard rescued more than 30 people, with helicopters being brought in from Scotland, Wales and Sligo.
Other people were helped by the police, ambulance service and other agencies.
The Department for Infrastructure said a “multi-agency conference meeting” was held on Wednesday.
In a statement the Department said: “Agencies deployed all available resources, working together to respond to a very high volume of calls from the public needing assistance and distributed sandbags.
“As a result of houses being flooded and motorists stranded, Derry City and Strabane District Council opened several centres to temporarily accommodate affected members of the public.
“These centres remained opened throughput the night. The Red Cross and the Western Health and Social Care Trust assisted in these centres during the night.
“The scheme of emergency financial assistance, which is administered by Councils is open to all residents significantly affected by flooding within their homes.”
The heavy rain on Tuesday night came after a yellow weather warning was issued for many parts of Northern Ireland.
All flights to and from City of Derry Airport are cancelled on Wednesday.
The fire service said it received 402 emergency 999 calls between 19:00 BST and 04:00 and during a peak period between 21:00 and 23:00 BST, they were getting an emergency call every 45 seconds.
“Firefighters worked in extremely challenging circumstances to reach people,” Alan Walmsley of the fire service said.
“A number of roads were impassable due to flooding and crews had to take alternative routes to attend some incidents.”
Ryan Gray, from the Coastguard, said: “Flood water up to 6cms in depth will take a human being off their feet and if it does so, it’s very unlikely that the person will be able to stand up again,” he said.
“This was a metre and a half of flood water – it was lifting vehicles up and taking them down, the current of the water
“There was a little bit of panic, thankfully the rescue teams are very well trained and they managed to calm the scene down and rescue people.
“All the emergency services – the police, fire and ambulance and Coastguard and the voluntary agencies all worked extremely well together last night in extremely challenging conditions.”
Bridges collapsed on the Camlough Road near Carrickmore, County Tyrone, and on Church Steet in Claudy, County Londonderry.
Dawn Grieve and her two young sons were rescued from their home in the Ivy Mead area of Derry by tractor.
“I had to leave the house, I actually got a tractor ride out of there by two local boys – their mum lives at the top of our street,” she said.
“I have two young boys, one is four and one is two, and we had to get out of there at about half three this morning.
“It was too bad for them – they were scared.”
Paul Duddy, a motorist caught up in the flooding, told BBC News NI he had “never seen anything like this in all my life”.
“It was terrifying, particularly whenever I seen the water coming up over the bonnet of the car. I don’t know how the car didn’t stall completely.”
Brigid Mullan, from Claudy, told BBC News NI she was stranded on the Victoria Road in Derry.
“We met a woman from Plumbridge who was very, very distressed so I offered to try to get her to Plumbridge.
“We didn’t get near Plumbridge, we got halfway there and the roads were flooded. We had to turn.
“And it is now exactly 11.15, and we are sitting slightly above the Everglades Hotel. There is nobody to come up and advise people the length of time it is going to take.”
SDLP leader and Foyle MLA Colum Eastwood tweeted that the flooding was “shocking”.
“Families and businesses struggling to cope and big questions for statutory agencies. Where was the preparation?”
The Foyle Arena was opened from 23:00 BST for those affected.
The Roads Service say the following roads remain closed on Wednesday morning: County Londonderry: A5 Victoria Road between Strabane and Derry, Gregg Road, Lower deck Craigavon Bridge, Church Brae, Drumnahoe Road, A2 Clooney Road (between Maydown and Eglinton), Ballynamee Bridge in Claudy has collapsed, Hall Road, Coleraine.
County Tyrone: Drumeen Road, Donaghanie Road, A505 Cookstown Road, Camlough Road, Whitebridge Road, Plumbridge – bridge closed, Crockanboy Road.
Roads reopened are: Maghermason, Skeoge, Cross Border Road/Donegal, Letterkenny Roundabout, Buncranna.
Translink has said there is severe disruption on the Coleraine to Antrim railway line due to the weather.
Bus substitutions are being provided.
There are also delays to some bus services in the north west.
Full details are on the Translink website.