For the second day in a row, school buses in parts of Lambton County are staying parked.
A snow squall warning posted for north and east Lambton was downgraded to a winter weather travel advisory Tuesday morning.
Environment Canada said additional snowfall accumulations of up to 10 centimetres were possible, with poor to near zero visibility in heavy snow.
As a result, the Chatham-Kent Lambton Administrative School Services cancelled school buses in Zones 1 and 4 Tuesday. Buses in all other zones were running normally.
Environment Canada said the lake effect squalls are expected to come to an end by noon.
The national weather agency said motorists may want to consider postponing non-essential travel until conditions improve.