Environment Canada is calling for heavy rainfall amounts in London, Komoka, Parkhill and Strathroy, as well as Eastern and Western Middlesex Counties.
20 to 30 mm of rain is expected to begin Sunday afternoon and last into the evening. Some additional light rain is likely to fall overnight into Monday.
The rain will be accompanied by strong winds gusting between 50 to 70 km/h, along with the risk of a thunderstorm early into Sunday evening.
The rainfall warning is being issued amidst what is being called a “potentially historic ice storm.”
London and surrounding areas were hit with freezing rain Saturday evening and a total ice build-up of 10 mm is expected for Sunday morning.
The weather has caused the Thames River Conservation Authority to issue a flood watch for the weekend.
Environment Canada advises that children and pets be kept away from creeks and river banks.
Salt trucks will be out on main roads and bus routes in London for snow removal.