SUDBURY -- Environment Canada has issued a severe thunderstorm watch for Timmins, Cochrane, Iroquois Falls, Little Abitibi and Kesagami Lake.

"Conditions are favourable for the development of dangerous thunderstorms that may be capable of producing large hail and torrential rain," Environment Canada said on Thursday afternoon.

"Scattered thunderstorms have developed across the area. These thunderstorms will be very slow moving. As a result, the main threat from these thunderstorms will be heavy rainfall with a slight chance of nickel size hail."

Heavy downpours can cause flash floods and water pooling on roads, the weather service said in a news release. "Lightning kills and injures Canadians every year. Remember, when thunder roars, go indoors."

Severe thunderstorm watches are issued when atmospheric conditions are favourable for the development of thunderstorms that could produce one or more of the following: large hail, damaging winds, torrential rainfall.

The Office of the Fire Marshal and Emergency Management recommends that you take cover immediately if threatening weather approaches.

To report severe weather, send an email to ONstorm@canada.ca or tweet reports using #ONStorm.

For more information on staying safe, click here.