A special weather statement is in effect for parts of the region, including Barrie, Collingwood, Midland, Orillia, and Washago.
Environment Canada says a cold front crossed southern Ontario this afternoon, and winds will shift to the west or northwest with gusts up to 80 km/h until late evening, before diminishing overnight.
The strong winds may cause some tree damage and isolated power outages, because many trees are still in partial to full leaf.
Alectra Utilities says thousands of residences in Vaughan are without power.
Hydro in that area is expected to be fully restored by 11:00 p.m.
