A status yellow wind warning has been issued for the counties of Munster, Connacht, Leinster, Cavan and Monaghan. County Donegal has been issued with an orange warning over strong winds.
The warnings will remain in effect from 6pm this evening until 6am tomorrow.
Strong gusts of 90 to 120 km/h and very high waves are forecast in Donegal, with a risk of coastal flooding.
The general outlook for the next couple of days is for very unstable and very windy weather, with some stormy conditions possible at times. Heavy rainfall over most of the country has also been forecast.
Temperatures will dip to about three degrees tonight, while tomorrow is expected to be a very mild, windy and wet day. Temperatures will range between 11 and 14C.
Saturday is expected to be a wet and windy day, with heavy rain affecting many parts of the country. It will also be a cold day, possibly 4 to 5C.
Wet and windy conditions will continue through Sunday and into next week.