Environment Canada has issued a snow squall warning for London, Ont., and Middlesex County ahead of the potential for heavy snowfall starting Monday night and lasting through Tuesday morning.
A warning is also in place for eastern Lambton County while snow squall warnings have been issued for areas further north.
Initially issued as a snow squall watch, Environment Canada upgraded the weather alert to a snow squall warning late Monday afternoon.
According to the national weather agency, snow squalls over Lake Huron are expected to head south Monday evening before tapering off Tuesday morning, with 15 to 20 centimetres over 12 hours possible in the heaviest bands.
However, with squalls, conditions can vary greatly and it is common to see “changes from clear skies to heavy snow within just a few kilometres.”
Meteorologists are warning motorists of the potential for near-zero visibility at times as well as for snow-covered and icy roads.
In London, the forecast is calling for a high of -9 C on Monday with an overnight low of -15 C. Snowfall of 10 to 20 centimetres is expected overnight with another two centimetres forecast for Tuesday morning, which is expected to have a high of -6 C accompanied by scattered flurries.