Southern Ontario residents should take in the fall vibes one last time, as a major dump of winter weather is expected to blanket some parts of the region with more than a half-metre of snow by the time the weekend draws to a close.

Meteorologists have put the province on notice ahead of a major weather event that could cause pandemonium in the coming days and weeks, marking a long-overdue end to an above-seasonal and mostly snow-free November in Ontario.

Mark November 29 on your calendars as the beginning of the end of the season, when what meteorologists describe as a "significant pattern change" could break down the doors of winter with the same level of menace as an axe-wielding Jack Nicholson in The Shining.

Parts of Ontario have experienced light dustings of snow so far this month, but a storm set to roll into the region this week threatens to bring the first opportunity for snow accumulation.

According to The Weather Network, cold Arctic air from the Prairies will create perfect conditions for lake-effect snow bands off of lakes Superior and Huron, and Georgian Bay. This system is expected to move into the GTA as early as Thursday into Friday.

According to Environment Canada's forecast for Toronto, there is a 40 per cent chance of snow or rain on Thursday, November 28, and 40 per cent chance of snow during the overnight hours. Flurries are expected in the days that follow.

However, the real winter blast is expected to arrive in Southern Ontario on Friday, bringing intense snowfall to areas of the province.

And this won't be your typical light dusting of snow, as some models are predicting that some regions of the province could be inundated with upwards of 50 cm of snow by the time the weekend draws to a close.

Significant Weather Outlook from @ECCCWeatherON for Friday and Saturday 👇

Significant Lake Effect snow possible, some areas may exceed 50cm snowfall by the weekend!#OnWX pic.twitter.com/9xKe3aoCUb

— WxOntario (@WxOntario1) November 24, 2024

Environment and Climate Change Canada (ECCC) warns that large snow totals threaten portions of southern Ontario near Lake Huron and Georgian Bay, as well as areas near eastern Lake Superior.

A significant weather outlook published by ECCC for November 29 warns that "The first significant lake effect snow of the season is likely beginning Friday."

"This has the potential to be a highly disruptive and prolonged event for areas near Lake Huron, Georgian Bay and eastern Lake Superior. While confidence is medium to high that lake effect snow and blowing snow will occur, confidence in exact locations to be affected as well as snowfall accumulations is low."

The government weather agency explains that predictions for these events are "highly variable." but cautions that "some areas may see well in excess of 50 cm by the end of the weekend."

While this news may have a large swathe of the province on alert, Instant Weather Ontario stresses that "snow squalls are highly localized events, and not everyone will experience intense snowfall totals."

"One area may receive significant snow accumulations, while locations just a few kilometres away might see only a dusting."

#ONStorm #ONwx ❄️🥶 Winter Roars Into Ontario This Week With Freezing Rain Threat; Snow Squalls Could Dump Up to 50cm of Snow

📅 Monday, November 25 - Sunday, December 1, 2024

⤵️ VIEW THE FULL FORECAST:https://t.co/YscwSNdisn

- Brennen pic.twitter.com/qsFhlY0yGA

— Instant Weather Ontario ⚡️ (@IWeatherON) November 25, 2024

People monitoring the incoming weather are already comparing it to the monster "snowmageddon" of Dec. 4-8, 2010, when record snowfall totalling 177 cm fell on Huron and Middlesex counties in the span of 201 hours.

One X user noted that, for this system of winter weather, snow may be measured in feet rather than centimetres or inches.

This 4-9 day period has a real shot of rivalling 2010 lads. Snow will be measured in feet lee of the lakes through early December. #onwx pic.twitter.com/uJ9EAEwsx0

— Troy Boone (@derecho_series) November 25, 2024

A major storm in late November into early December has been anticipated by European weather modeling since earlier this month, though this model is now converging with North American forecasts.

This divergence in weather models was explained to blogTO by ECCC meteorologist Trudy Kidd, who says that there are "several factors" behind the differences, and that "even small differences in the initial conditions" can be "amplified over time."

With just days away and models now more or less aligned, it seems the European system will come away the winner in this case, calling the coming storm far ahead of the forecasts now being shared by ECCC.

"Sometimes, especially when it comes to winter weather forecasting, you can even see big differences a week in advance," said Kidd, in a now somewhat prophetic statement.