"As temperatures plummet with the passage of a cold front," the weather service said, "there may also be a brief period of freezing rain during the changeover from rain to snow."
The statement covers:
- Guelph, Erin, Southern Wellington County.
- Waterloo, Kitchener, Cambridge, the Region of Waterloo.
Environment Canada warned that roads and walkways could become icy and slippery.
"The snow is forecast to taper off behind the cold front, limiting snowfall amounts to a few centimetres at most." the weather service projected.
A separate flash freeze warning was issued for Northern Wellington County, advising a "hard freeze" will freeze pooling water, slush and rain as temperatures plummet.
Friday expect periods of rain changing to periods of snow late in the morning. As that happens, there's a risk of freezing rain in the morning and early in the afternoon.
Wind northwest 30 km/h gusting to 50. Temperature falling to –7 in the afternoon.
The sky will cloud over and bring a 40 per cent chance of flurries. Wind north 40 km/h gusting to 60. Low –13.