Environment Canada posted a snow squall warning for Watford - Pinery Park and Eastern Lambton County late Monday afternoon and then extended it to include west Lambton in the evening.
An intense band of lake effect snow formed off of southern Lake Huron in a cold north-northwesterly flow.
The weather agency says the band weakened Monday night as a ridge of high pressure moved in.
The warning for east Lambton ended before 9pm and just after 10:30pm for the western part of the county including Wyoming and Petrolia.
There were reports of heavy snow and poor to nil visibility.
Local snowfall amounts of up to 15 cm (6 in) were possible along with near zero visibilities.
Public Safety Canada encourages everyone to make an emergency plan and get an emergency kit with drinking water, food, medicine, a first-aid kit and a flashlight.
A very cold airmass has settled across much of southern Ontario again.
Environment Canada issued an Extreme Cold Warning for neighbouring London-Middlesex with windchills of -30 C possible Monday night and early Tuesday.
A Cold Weather Alert posted by Lambton Public Health was in effect for Sarnia-Lambton with the air temperature expected to drop to -16 C.
