Met Éireann has warned of difficult driving conditions this morning, as a Status Yellow warning for fog is in place for 11 counties.
The warning for counties Cavan, Monaghan, Dublin, Kildare, Laois, Longford, Louth, Meath, Offaly, Westmeath, and Wicklow will be in effect until 10am.
The forecaster said that dense fog is expected in some parts.
Poor visibility will result in difficult driving conditions for motorists.
The Road Safety Authority urged road users to make sure their vehicles are as safe as possible before driving in the conditions.
It comes after the country experienced several days of cold weather, especially in the evenings, with nighttime temperatures dropping as low as -5C on Thursday.
Separate Status Yellow rain and wind warnings are due to come into effect for seven counties tonight and tomorrow.
A rain warning for counties Donegal, Leitrim, Mayo and Sligo will come into effect at 9pm tonight and last until 9pm tomorrow.
A wind warning will come into effect for Leitrim, Mayo, Sligo, Clare and Galway at 6am tomorrow and will last until 2pm.
A separate wind warning will come into effect for Co Wicklow at 10am tomorrow and will be in effect until 5pm.
