Environment Canada says a wind gust of almost 100 km/h was recorded in Sarnia early Wednesday afternoon.
The national weather agency says a gust reached 96 km/h at 2:06pm.
A wind warning was in effect for a few hours as fast-moving bands of heavy showers with small hail and the odd thunderstorm raced across the region.
Some trees and branches came down causing hydro outages in parts of Sarnia-Lambton.
The major service disruption impacted central and east Sarnia including Lambton Mall and businesses along part of the busy London Rd. corridor.
Power was out for about an hour.
Environment Canada says a survey team was being sent Thursday to assess damage in the Mount Forest area and possibly Brampton.
There was damage to farm buildings and some trees toppled in the late afternoon northwest of Mount Forest and two houses under construction were damaged at Brampton.
