Thunderstorm & Lightning Safety Tips
What Is a Thunderstorm?
A thunderstorm is a weather event that produces lightning, thunder, heavy rain, strong winds, and
sometimes hail or tornadoes. Thunderstorms form when warm, moist air rises rapidly into the
atmosphere and collides with cooler air. Lightning is one of the most dangerous aspects of
thunderstorms - it can strike miles away from the storm's center, even under clear skies, and kills
hundreds of people worldwide each year.
Early Warning Signs
- Rapidly darkening skies or sudden change in sky color (green or yellow tinge)
- Increasing wind speeds or sudden calm before the storm hits
- Distant rumbles of thunder - if you can hear thunder, lightning can reach you
- Tall, dark cumulonimbus clouds building on the horizon
- Hair standing on end or a tingling sensation - a sign lightning may be imminent
Before a Thunderstorm (Prepare)
- Sign up for local weather alerts and monitor forecasts during storm season
- Prepare an emergency kit with water, food, flashlight, batteries, and first aid supplies
- Trim trees and branches near your home that could fall and cause damage
- Install surge protectors and consider an uninterruptible power supply (UPS) for electronics
- Identify safe indoor shelter locations in your home, workplace, and surrounding neighbourhood
During a Thunderstorm (Stay Safe)
- Go indoors immediately - a sturdy building or hard-topped vehicle is safest
- Stay away from windows, doors, and exterior walls
- If caught outdoors, crouch low with feet together - do not lie flat
- Wait 30 minutes after the last thunder before going outside
- Don't shelter under trees, isolated structures, or near metal objects
- Don't use corded phones, electrical appliances, or plumbing during the storm
- Don't remain in open fields, hilltops, or near water bodies
- Don't ignore emergency alerts or evacuation orders