The warning was issued overnight.

A yellow weather warning has been issued for the entire country as fog descends across Ireland. The warning, pertaining to fog and mist, was issued yesterday and is valid valid from 1am on Monday to 11am this morning. Met Éireann has warned that the fog may affect visibility across the country this morning. They said: "Mist and fog will form again tonight, becoming dense, especially in some midland areas, leading to poor visibility." Once the fog lifts, the day is expected to remain bright and sunny, with temperatures reaching as high as 16 degrees in some parts of the country. Later on this evening, the night will become "generally cloudy with patchy light rain and drizzle affecting Ulster and north Connacht." It will be drier elsewhere with the best of any clear spells in the south and lowest temperatures will be between 6 and 10 degrees, falling to 4 or 5 degrees in some parts of the southeast. More mist and fog will develop later on tonight as light westerly winds fall calm. October has been unseasonably warm this year as temperatures were reported to have reached highs up to 20 degrees in some parts of the country last week.