Environment Canada says we’re in for another roller-coast week of weather.

A low pressure system that brought heavy rain to some areas and 20C temperatures to others will bring winter-like weather to most of the province before it moves through Tuesday afternoon.

While today is expected to be warm day for some regions, a big shift is coming.

Environment Canada said in a special weather statement that showers and wind gusts up to 85 kilometres per hour are moving in from Southwestern Ontario, bringing an end to the warmth in most regions.

Then an Arctic cold front will sweep across Southern Ontario this afternoon, plunging temperatures to the near-freezing point or lower by Tuesday morning.

The weather statement is in effect for:

  • Barrie - Collingwood - Hillsdale
  • Midland - Coldwater - Orr Lake
  • Orillia - Lagoon City – Washago
  • Innisfil - New Tecumseth - Angus
  • Orangeville - Grand Valley - Southern Dufferin County
  • Shelburne - Mansfield - Northern Dufferin County
  • Newmarket - Georgina - Northern York Region
  • Pickering - Oshawa - Southern Durham Region
  • Uxbridge - Beaverton - Northern Durham Region
  • Vaughan - Richmond Hill - Markham

Showers will change to a few centimetres of snow from Georgian Bay to Lake St Clair tonight.

There is also a risk of a few hours of freezing rain or ice pellets, Environment Canada warns.

Temperatures will be sharply colder on Tuesday. And drivers should be ready for a quick return to winter driving conditions.

Temperatures are expected to be closer to normal by the end of the week.