Heavy thunderstorm activity rolled through the area early in the morning Thursday.
Sarnia Lambton received about 18 mm of rain.
Lightning associated with the storm activity disrupted power in a number of locations in Sarnia Lambton including parts of Bright's Grove, St ClairTownship,and Watford. Service was restored by 5am.
Sarnia Lambton remains under a heat warning with the mercury expected to hit 30 C Thursday with a humidex in the 39 C range.
Cooler air will arrive Thursday night with a forecast low of 18 C.
