A mammoth winter storm is expected to blast much of Southern Ontario Saturday morning.

Environment Canada says Hamilton and Niagara Region could receive 15 to 25 centimetres of snowfall.

The weather agency says a storm to the south of the Great Lakes will pick up extra moisture resulting in higher snowfall totals.

The areas will likely be hit by winds gusting up to 60 kilometres an hour which will generate widespread blowing snow and cold wind chill values near minus 20.

Officials are advising drivers to postpone any non-essential travel because near zero visibility will be likely at times.

Highways, roads, walkways and parking lots may become difficult to navigate due to accumulating snow. Public Safety Canada encourages everyone to make an emergency plan and get an emergency kit with drinking water, food, medicine, a first-aid kit and a flashlight.

Environment Canada says areas north of Hamilton and Burlington will see less snowfall amounts.