On Thursday night we can expect wintry showers of hail, sleet and snow - "most frequent in Ulster, Connacht and in west Munster, but in other areas also".
There will be icy stretches too, and while north and northwest counties will be most at risk, areas of higher ground elsewhere are also at particular risk.
Thursday is set to be a cold, windy day, with widespread wintry showers.
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The warning applies to Donegal, Galway, Mayo and Kerry, where southerly winds of 50 to 65 km/h are expected, with gusts of 90 to 110km/h along coastal areas on Wednesday.
"The UK Met Office have named it Storm Caroline".
"Severe winds will affect parts of Scotland, but it will generate strong and blustery winds over Ireland also", reads the official website.
Forecasters had earlier warned it will be "bitterly cold" for the rest of the week despite a mild day today.
It is one of three weather warnings now in place around the country.