A status yellow snow and ice warning has been issued for counties Donegal, Leitrim and Sligo on Wednesday morning.
Wintery showers and icy conditions are forecast in these parts from 5pm Wednesday evening.
The weather warning is expected to be lifted at 11am Thursday.
In other counties, Met Éireann has forecasted a mainly sunny day.
Isolated showers may turning wintery in parts of Ulster and north Connacht.