A Severe Thunderstorm Warning has been issued for Dryden, Vermilion Bay and Sioux Lookout areas.
Environment Canada says conditions are favourable for dangerous thunderstorms that may be capable of producing damaging wind gusts and large hail.
A special weather statement is also in effect for the area for extreme heat this weekend.
There should be some relief from the heat tonight with temperatures falling into the teens.
Low thirties are expected again Saturday (tomorrow) followed by a very warm night, with lows likely not falling much below 20 degrees Celsius.
Slightly cooler temperatures are expected on Sunday.
