Met Éireann has issued a Status Yellow Fog Warning for several areas including Clare.
The warning will affect Galway, Leinster and all of Munster including Clare.
Forecasters say fog will develop overnight and could be dense in places resulting is poor visibility and possible hazardous travelling conditions.
The warning will be effective from 10.00pm Friday and remain in place until 10am on Saturday.
Forecast
Friday Night
Mostly cloudy and largely dry apart from some patchy light rain at first. Widespread mist and fog will form in near calm conditions and the fog will become dense in places. Lowest temperatures of 2 to 5 degrees.
Saturday
Widespread mist and fog at first tomorrow with poor visibility, clearing from most areas through the morning but possibly lingering in some places as winds remain very light. Largely dry and mostly cloudy at first though sunny spells will develop through the day. A cooler day with highest temperatures of 7 to 11 degrees.