Drivers in the London area will be put to the test Thursday as forecasters are calling for fog in the morning, and snow in the evening.
They say both have the potential to cause issues on area roads.
The national weather agency says dense fog is affecting portions of southwestern Ontario, but should dissipate later this morning.
Motorists are being asked to prepare for areas of near-zero visibility as driving conditions can change quickly.
Further to that, Environment Canada has also issued a winter travel advisory for Thursday evening to warn of snowfall that could impact driving conditions.
Forecasters are tracking a system that is expected to move into southwestern Ontario after 6 p.m. Thursday.
They say the heaviest snowfall is anticipated during the first two or three hours of the system, with lighter snowfall expected after that.
Snowfall accumulation of 5 cm to 10 cm is possible Thursday night, with the bulk of that likely coming in the first few hours.
Both advisories are in place for London, Parkhill, Strathroy, Komoka and parts of Middlesex County.