Messy weather is heading for Toronto and the surrounding Southern Ontario region to close out the workweek, thanks to a low-pressure system promising a blanket of snow and the potential for freezing rain expected to arrive on Thursday.

And the forecast just got even worse.

Environment Canada issued a special weather statement warning of the coming system on Tuesday afternoon, and updated that statement in the early morning hours on Wednesday to reflect projections for even more snowfall than first anticipated, now forecast to reach as much as 15 centimetres by Friday morning.

Environment Canada warns that conditions may include freezing rain early Thursday before transitioning to snow around noon, increasing in volume into the afternoon and evening hours, just in time for that already-frantic end-of-day commute.

That snowfall will be preceded and accompanied by strong winds of up to 70 km/h, expected to be felt the strongest near Lake Ontario's shores, lasting from Thursday morning into the afternoon. Gusts could potentially result in loose objects thrown around by wind and local power outages.

Environment Canada once again upgraded its weather statement early Wednesday afternoon, issuing a Winter weather travel advisory for Thursday, warning motorists to take extra caution on roads.

"Motorists should expect hazardous winter driving conditions and adjust travel plans accordingly. Surfaces such as highways, roads, walkways and parking lots may become icy and slippery," the government agency warns.

⚠️Special Weather Statements have been issued for much of southern Ontario!⚠️
Be prepared for hazardous winter travel conditions later this week.

Latest alerts 👉https://t.co/jIXI12HYbD#ONwx #ONStorm pic.twitter.com/3tLMbInMrX

— ECCC Weather Ontario (@ECCCWeatherON) December 13, 2022

In addition to snowfall accumulation of up to 10 cm, road hazards may include ice accretion of a few millimetres, with Environment Canada cautioning that "there may be a significant impact on rush hour traffic in urban areas."

The snow is expected to taper off to mild flurries or drizzle by Thursday evening, and winds will similarly drop off by the evening, though snow accumulation will likely remain a factor complicating the Friday morning commute.

Some areas will be luckier than others, including neighbourhoods near the shoreline of Lake Ontario. Snow may be lighter around these parts of the region, expected to transition to rain and making for easier clean-up the morning after.