That fog that covered parts of the state on Monday afternoon is here to stay until Friday, according to the Bureau of Meteorology.

Thick fog moved over parts of the Adelaide metro area yesterday afternoon after being blown in from metropolitan waters.

Forecasters from the Bureau of Meteorology have said that wet conditions on the weekend made for good conditions for the fog.

The Bureau’s senior forecaster Brett Gage told The Advertiser that the fog is here to stay for the rest of the week.

“We’ll have areas of fog right through until Thursday and then finally by Friday it should be dry enough to have fog Friday morning.”

Reduced visibility has led to SA Police issuing a road weather alert for Adelaide motorists this morning.

Motorists are advised to slow down, maintain safe distances with other vehicles and to turn on their headlights.