A status orange wind warning is in place for Mayo, Sligo, Leitrim, Donegal, Galway, Clare and Kerry from 6am this morning to 8 o'clock this evening.
Met Eireann says Storm Ciara will continue to produce very strong westerly winds in coastal areas, with gusts of between 110 and 130 km/h.
A combination of spring tides and high seas will result in a significant risk of coastal flooding.
The rest of the country is under a less severe status yellow warning, as well as a yellow snow & ice warning.
Met Eireann is warning of widespread wintry showers today and tomorrow, with some snowfall accumulations especially in the west and north of the country.
Hundreds of customers are without power in the Claremorris area this morning due to several faults following the storm, are power supplies are due to be restored between 11am and 1 pm today.
In relation to flooding in Sligo, the Collooney to Ballygawley road is closed due to a river bursting its banks, while the Ballymote/ Gurteen road is impassable at Rathmullen Bridge due to flooding.