Update: As of 7:40 am, Environment Canada has ended the frost advisory.
An unseasonably cold weekend could be capped off with a blanket of frost in the area.
Environment Canada has issued a frost advisory for London-Middlesex, as a cold arctic air mass sits across Southern Ontario.
Temperatures could plunge below 0 C overnight Sunday, and areas where wind can become light or calm under clear skies could see frost develop.
The weather authority advises residents to protect and take preventative measures for tender plants and trees.
Temperatures are expected to shoot back up Monday, with a predicted high of 16 C.
