OTTAWA -- A thick blanket of fog is expected to cover Ottawa all night.

Environment Canada issued a fog advisory for Ottawa, warning there will be "near zero visibility in fog."

"Areas of dense fog will persist across the region (Thursday night)," said the statement late Thursday.

At 7 p.m., the visibility in Ottawa was 0.4 kilometres.

Here is a look at the Environment Canada forecast:

Tonight: Cloudy with a chance of drizzle. Fog patches. Low plus 4C

Friday. Cloudy with a chance of showers. Fog patches dissipating in the morning. High 6C.

Saturday: A mix of sun and cloud with a chance of showers or flurries. High plus 4C

Sunday: A mix of sun and cloud. High plus 5C

Monday: Periods of rain. High 8C.