Some 75,000 homes and businesses face a second day without power today with some of the worst hit areas in Kerry, Wexford and Limerick.
With the latest Atlantic depression set to bring heavy rain to widespread areas later today, electricity supplier ESB said 185,000 customers have been reconnected.
Floods are expected to hit Cork city tonight as heavy rains and high tides combine.
"All available resources have been deployed to restore power to customers as quickly as possible, however we cannot guarantee at this stage when customers will have their power restored," a spokesman warned.
Tens of thousands are still without phone communications.
The ESB said there are about 2,000 locations nationwide where timber has to be cleared from power lines and its repair crews have needed 1,000 wooden poles, 250km of conductors and 400 transformers to get supplies back up.
Elsewhere, the power cuts have caused safety scares for clean drinking water in some regions of the south east.
Boil water notices were widespread across Co Limerick while 80 supplies in Cork are also feared at risk.
Met Eireann has warned of winds gusting to 110km/h today and a band of heavy rain moving north with snow - 3cm in some places - to hit some parts of Connacht, Ulster and north Leinster.