TORONTO -- Environment Canada issued a special weather statement early Thursday for most of southern and eastern Ontario warning of another wave of bitter cold.

The agency says a northwesterly flow will develop today and bring lows in the minus 30 Celsius range to many places until Sunday.

The statements runs from the Windsor area in the east to the Parry Sound region and east into Quebec.

Environment Canada has also issued snow squall warnings for communities on the east side of Lake Huron, with up to 15 centimetres of snow likely in the warning zones.

Most areas of southern Quebec are also under winter storm warnings while northern areas are being warned to brace for extreme cold which could reach minus 47 in some places.

Environment Canada says the Eastern Townships south of Montreal and the Beauce region are also under a snowfall warning, with up to 20 centimetres expected by overnight.

In the Montreal area, including Laval, the Eastern Townships and the Laurentians, a smog warning is in place due to what the weather office says is the result of high concentrations of fine particulates. Montreal residents in particular are advised to stop using wood-burning stoves or fireplaces until the warning is lifted.