Canadian Lightning Danger Map (CLDM) – Ontario & the Great Lakes

Lightning Facts:

  • During the summer in Canada, lightning strikes every three seconds.
  • Each strike has enough energy to provide a house with electricity for an entire week.
  • If lightning strikes nearby, it also has enough power to seriously injure or kill a person.
  • Lightning is highly unpredictable. It is impossible to predict where and when the next strike will hit.
    However, Environment Canada’s Lightning Danger Map can help you reduce your risk of being seriously injured or killed by lightning.
  • The Canadian Lightning Danger Maps use information from recent lightning strikes to create high danger zones indicated in red. The danger zones help show you where the lightning risk is greatest.


  • The Canadian Lightning Danger Map (CLDM) represents areas at greatest risk of being struck by lightning in the next 10 minutes.
  • Times are expressed in Coordinated Universal Time (UTC). (UTC = EDT + 4)
  • The interval between maps is 10 minutes. Please re-fresh your browser to ensure you have the latest map.
  • For more information about the CLDM follow the link to the CLDM on the Lightning in Canada site.
Current Weather Conditions / Radar Overview Great Lakes