The AA was this afternoon warning drivers to take extra care on the roads as heavy rainfall has caused poor road conditions and wet road surfaces in many areas.
Met Eireann is forecasting more rain with occasional thundery downpours in the next few days.
A flood warning has been issued for Greystones in Co. Wicklow, while areas of Cavan, Monaghan, Mayo, Leitrim, Sligo and Roscommon are also at risk.
The heavy rainfall is set to continue throughout the day - as between 30 to 50 millimetres is forecast to fall.
“All areas have had some rain in the last 24 hours with some extremely heavy localised showers," said Conor Faughnan of the AA.
“This has meant some very testing driving conditions and drivers must take extra care.”
The organisation said it had today had its busiest morning for breakdowns since last January, with nearly 300 call outs during the morning.
The worst affected area was Dublin; wet conditions over the weekend resulted in an increased number of minor collisions needing to be towed, and the Monday morning rush saw a large number of cars failing to start because of dampness in the electrical systems.
“We are used to this in the AA, but I guess it tells us that summer is officially over.” Faughnan said.