Drivers in Sarnia, Petrolia, and Western Lambton County should use extra caution on the roads this Friday, April 17, 2026, due to a dense fog advisory issued by Environment Canada.
The advisory, which went into effect at 6:13 p.m. on Thursday, April 16, 2026, warns of near-zero visibility that may create hazardous travel conditions. Measurements taken at the Sarnia Chris Hadfield Airport at 5:13 a.m. Friday confirmed visibility had dropped to 0.6 kilometres, with conditions including 100 per cent humidity and light winds.
Forecasters expect the fog to clear later this morning. Once the fog lifts, residents can look forward to a mix of sun and cloud with a daytime high of 18°C.
This follows a history of similar weather events in the region. Most recently, on March 4, 2026, heavy fog forced the cancellation of all school buses across all eight zones in Sarnia-Lambton. Due to the area’s location at the southern end of Lake Huron, residents are often familiar with these types of sudden visibility changes caused by local temperature differences near the water.