Met Éireann has warned fog is likely to persist for this evening and the early part of the night. A number of flights have been cancelled or diverted flying into Knock Airport.
However, the fog should dissipate tonight.
The fog is still dense, though not as much as early this morning, causing reduced visibility on roads. Frost that affected many roads this morning has cleared.
Munster and much of Ulster are clear of fog, which persists for a large part of Leinster and Connacht.
Tomorrow is expected to be breezy with a bit of rain, with top temperatures between 9 and 13 degrees and southeasterly winds.
The heavy fog that blanketed the city last night and earlier today prompted an Orange Level weather warning from Met Éireann.
Met Éireann has three levels of weather warning: Yellow, telling people to be aware; Orange, warning people to be prepared for certain anticipated conditions; and Red, telling people to take action.