Multi-vehicle crash, snow squalls shut down 30 km stretch of eastbound 402
Winter may not start until Dec. 21, but some southwestern Ontario motorists have been getting an early preview of what they may see on the roads over the coming months.
That includes snow squall-induced closures along Hwy. 402., west of London.
A 30-kilometre stretch of the 402's eastbound lanes were closed Monday evening by provincial police because of poor weather and road conditions, and was expected to last several hours.
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The closure, from Oil Heritage Road to Kerwood Road, extended one that had been in place since 3 p.m. following a crash north of Watford involving two transport trucks, including one which jackknifed. No serious injuries were reported, police said.
Snow squalls have been streaming south off of Lake Huron throughout the day, blanketing areas near the border between Lambton and Middlesex, and bringing white-knuckle driving to parts of the 402.
Lambton County OPP direct eastbound traffic off of Hwy. 402 at Oil Heritage Road on Nov. 10, 2025. Poor weather and road conditions, and an earlier collision, prompted police to shut down a 30-kilometre stretch of the eastbound lanes. (Ontario Ministry of Transportation)
In a statement around 7 p.m., Lambton OPP said they expected the eastbound 402 would remain closed "for the next several hours" between Oil Heritage and Kerwood roads to allow for vehicles to be removed, and to ensure the road is safe.
"Motorists are urged to avoid the area and delay non-essential travel until conditions improve."
Further south, the tail end of the lake effect snow band managed to impact traffic on Hwy. 401 near Dutton and West Lorne, where a jackknifed tractor trailer forced a closure of a westbound lane late Monday afternoon. The lane has since reopened, police said.
About 10 kilometres east of Oil Heritage Road, eastbound traffic is diverted off Hwy. 402 at Hwy. 21 because of poor weather conditions and an earlier collision further down the highway near Nauvoo Road, Nov. 20, 2025. (Ontario Ministry of Transportation)
Heavy snow is expected to continue in the area into overnight hours, according to Environment Canada forecasts.
Snow squall warnings remained active for parts of Elgin, Huron, Lambton and Middlesex Counties around 8 p.m., calling for significant snowfall amounts into Tuesday morning.
Amounts of 15 to 30 centimetres were expected, with localized amounts over 50 centimetres possible in southern Huron and western Middlesex, the advisory said.
The band of lake effect snow was expected to shift east later Monday night, but may be stationary over parts of Middlesex and Huron with heavy accumulations possible.
"The worst conditions are expected to remain to the west and northwest of the City of London," the advisory reads.
The season's first brush with snow over the weekend kept provincial police in Essex County busy.
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Essex OPP say they responded to 20 separate collisions along Hwy. 401 within a five-hour period on Sunday afternoon because of poor weather and road conditions. No serious injuries were reported.
In one incident, an OPP vehicle was struck from behind as officers assisted at the scene of an earlier collision. Two officers sustained minor injuries and were treated in hospital.
"As winter weather arrives, drivers are reminded to adjust their mindset and driving habits for changing road conditions," police said.
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This article, written by Matthew Trevithick, was originally published for CBC News.