Fog advisories are in effect for parts of southern Ontario including Hamilton, Halton and Niagara regions.

Environment Canada says dense fog patches have caused “near zero visibility” in some areas.

Thick fog this am! Be very careful! Drizzle then rain later with hi of 2. Tonight rain and fog as temps rise to 7. Wet and windy tomorrow. Details at 6. @morninglive

— brianwoodchch (@BrianWCHCH) January 22, 2018

The agency says conditions are expected to improve but the fog will likely continue throughout Monday and overnight into Tuesday morning.

Check your flight status before heading to the airport as well! @morninglive https://t.co/NtRdX5OQiQ

— Diana Weeks (@dweeks_CHCHnews) January 22, 2018

A significant freezing rain even is also expected for some areas including Caledon and Dufferin County.

Forecasters are warning drivers that highways, roads, walkways and parking lots may become icy and slippery.

The national weather forecaster says a system known as a “Colorado low” will move across the lower Great Lakes on Monday and is responsible for a snowfall warning in northeastern Ontario, where forecasters predict up to 20 centimetres of snow.

Good morning, Halton.

Due to fog and the possibility of freezing rain, there are some school bus cancellations in the north end, so expect more children to be on foot today.

✅ Slow down
✅ Avoid passing
✅ Increase following distance
✅ Remain patient

Have a safe day. ^jh

— Halton Police (@HaltonPolice) January 22, 2018