Met Éireann has issued a status red rainfall warning for areas of Connacht as well as counties Donegal, Clare, and Kerry as the fourth storm of the winter approaches.
Incessant falls of heavy rain are forecast overnight and for all of Saturday as Storm Desmond approaches the country.
Accumulations in excess of 70mm are expected, with greater totals on higher ground.
Strong winds with speeds of 55 to 75km/h and gusting to 100 to 120km/h are also forecast throughout the period.
Status Red warnings are relatively rare and are issued to alert people to take action to protect themselves and/or their properties.
The Road Safety Authority has advised drivers to check local and national forecasts and traffic updates before setting out.
They have warned drivers to be aware of possible fallen trees and to avoid driving through flooded areas.
