Update: Dense fog at Shannon Airport has resulted in two flights diverting to Dublin Airport this morning.
Aer Lingus flight EI-110 from New York to Shannon diverted to Dublin this morning as a result of poor visibility in Shannon.
Ryanair flights FR-93 from Stansted; FR4984 from Poznan and also diverted to Dublin.
All three flights entered holding patterns away from the airport in the hope the conditions would improve.
Meanwhile, another Ryanair flight from Tenerife in the Canary Islands to Cork diverted to Shannon because of poor visibility there.
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
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.