Learn Environment Canada's 30-30 rule:

• Take appropriate shelter when you can count 30 seconds or less between lightning and thunder.
• Remain sheltered for 30 minutes after the last thunder. 

IF YOU ARE INDOORS:

• Keep away from doors, windows, fireplaces, and anything that will conduct electricity, such as radiators, stoves, sinks, and metal pipes.
• Do not use computer or wired video game system.
• Use battery-operated games.
• Don't take a shower or a bath.
• Stay inside.

IF YOU ARE OUTDOORS:

• Immediately seek shelter in a building or depression in the ground, but never under a tree.
• Do not hold anything that is a conductor of electricity, such as a cell phone, an iPod, or an umbrella.
• Get to shore if you are in or on the water.
• If you are in a car, stay in it, but stay away from trees.