Updated 11:45
Met Éireann has issued a weather warning for parts of the midlands and east coast of the country for the next 24 hours.
A status orange alert is in place until 6 o'clock tomorrow morning in Leinster and counties Cavan and Monaghan.
Heavy rain, ranging from 25 to 40 mm, has already fallen in places. Up to 100 mm of rain is expected to fall in the next 24 hours in Dublin.
DART services have resumed after flooding caused the service to be suspended between Dun Laoghaire and Bray:
Dart services back operating south of Dun Laoghaire after earlier disruption due to flooding
— Iarnród Éireann (@IrishRail) August 2, 2014
Flooding is already a problem in Santry, Malahide, Ballymun and Clontarf. Flooding is receding on a section of the Ballymun Road between Collins Avenue and St. Pappin Road. In Dublin, motorists are advised that the Old Swords Road is now passable at Schoolhouse Lane following earlier flooding.
There is also excess water on Santry Lane. Dublin Bus was unable to serve the Santry Village or Beaumont areas. Routes 16, 33 and 41 were diverted via the M1 and Coolock Lane in both directions. As of 10 am the Dublin Bus website is reporting no diversions are in place on any routes.
Excess surface water is also causing problems around counties Offaly, Meath, Longford and Louth.
Elsewhere, a status yellow rainfall warning remains in place for Tipperary and Waterford.
Meanwhile, motorists are being urged to drive with care this bank holiday.
Figures show 111 people have died on Irish roads so far this year, representing an increase on last year.
