Motorists are being advised to drive with care this evening as heavy rainfall batters the country once again.
Met Eireann are warning of heavy rain tonight and tomorrow. The rain will ease on Thursday and Friday before returning with a vengeance at the weekend.
In Dublin tonight, flooding is causing problems particularly on the north side of the city. Parts of the Old Swords Road, Coolock Lane, Griffith Avenue and the Ballymun road have been flooded as has the M50 at the Ballymun exit.
The N3 is closed at Blanchardstown in both directions due to flooding. Gardai are asking motorists to avoid the area and take an alternative route.
In Louth, the R173 Carlingford to Newry road is flooded and impassable. Drivers are being advised to avoid Omeath and divert via Dundalk.
Heavy rain and surface water are being reported in many parts of the country. Drivers should reduce speed, keep a safe distance from the vehicle in front and drive with care.
Earlier, a man in his early 40s died when his car was involved in a crash in Co Down after heavy rain had made driving conditions treacherous across much of Northern Ireland.
Five motorists had to be rescued from their cars by the Fire & Rescue Service when they were trapped in flood water on a road near Moira, Co Down.
Three teenage campers also had to be rescued from the Mourne Mountains earlier today after their camp was washed out by torrential rain.
Wet and miserable, the three girls - aged between 15 and 17 - called the Mourne Rescue Team for help after finding their route down from the mountains in Co Down blocked by a swollen river early this morning.
Ed Kilgore, chairman of the Mourne Rescue Service, said: "A group had been out camping and were woken by the rain at around 5am and found their camp washed out.
"When they tried to make their way back down the way they had gone up, they found their way blocked by a river that was so badly swollen they could not get across.
"If they had decided to try to get across the river it could have been nasty. In the darkness and bad weather they panicked a bit and rang for assistance."
The girls were "wet and miserable and relieved" when the rescue team arrived to guide them down, he said.
Police warned of flooding in many areas in the North as the downpour continued and said the Rathfrisland Road at Banbridge, Co Down, had been closed by floodwater after a nearby river burst its banks.
The Met Office had issued a severe weather warning for Northern Ireland with a predicted 30 to 50mm of rain overnight.
Police warned of flooding on roads in a number of places today, including on the main A1 Belfast-Dublin Road at Banbridge, Co Down.
The 8am Stena Lynx sailing from Rosslare to Fishguard tomorrow morning has been cancelled due to the bad weather conditions. Passengers are advised to contact Stena Line for alternative arrangements: 053 33158.