The warning is in place until 2am in the early hours of tomorrow morning.
A Met Office spokesperson said: "The strongest winds are expected to transfer eastwards across the warning area before clearing by late morning".
A status yellow alert for wind is also in place for seven other counties in the west and north-west.
Met Éireann has advised that "westerly winds will reach mean wind speeds of 55 to 65km/h with gusts of 90 to 110km/h". Thre will be high seas along Atlantic coasts with a risk of coastal flooding.
There will be high or very high seas which are going to affect the Atlantic Seaboard over the next few days, leading to an increased risk of coastal flooding.
Thursday night features showers of rain, hail, sleet and snow.More news: How much is Khloe Kardashian's net worth?
"A spell of persistent and heavy snow is expected to develop".
And overnight, the snowfall will be heavy as temperatures plummet to 0.
Highest accumulations are expected in Ulster and northwest Connacht. Southwest to west winds increasing gale force to strong gale force and occasionally storm force this evening and overnight on Irish coasts from Belfast Lough to Hook Head to Rossan Point and on the Irish Sea.
Some of the showers will be heavy and thundery with some hail, sleet and snow. Cold with afternoon temperatures of just 3 to 7 degrees.
The chief forecaster's assessment adds: "A deepening area of low pressure is expected to track east across the United Kingdom during Wednesday night and early Thursday". But as the rain clears winds will moderate.