Fire Cause Guide
Lightning-Caused Fires
The most common natural cause of wildfires in British Columbia.
How Lightning Starts Fires
Lightning strikes can ignite vegetation in several ways. A positive lightning strike (cloud-to-ground) delivers enormous energy to a single point, heating organic material to its ignition temperature instantly. "Dry lightning" â thunderstorms that produce lightning but little to no rain â is particularly dangerous because there is no accompanying moisture to suppress ignition.
Key Facts
đ ~60% of BC Wildfires
Lightning accounts for roughly 60% of all wildfires in British Columbia, and these fires account for the majority of total area burned each season.
đŠī¸ Holdover Fires
Lightning can ignite organic material deep in the duff layer (decomposing plant matter). These "holdover fires" may smolder undetected for days or weeks before surfacing.
đī¸ Remote Locations
Lightning fires often start in remote, inaccessible terrain â making early detection and suppression challenging. Satellite and lookout detection are critical.
đ Peak Season
Lightning fires peak in July and August when thunderstorm activity combines with dry fuel conditions. A single storm can produce hundreds of new fire starts.
Detection Methods
- Lightning Location Networks (LLN): BC uses the Canadian Lightning Detection Network to map every lightning strike in real-time, cross-referencing with fire starts.
- Satellite Monitoring: MODIS and VIIRS sensors detect thermal anomalies within hours of ignition.
- Fire Lookout Towers: Staffed towers in high-risk areas provide visual confirmation of smoke from lightning starts.
- Patrol Flights: Aerial patrols systematically survey lightning-prone areas after storm events.
Where Lightning Strikes Become Fires
The chain from a cloud-to-ground strike to a holdover fire requires dry fuels, low humidity, and an ignition point that escapes early detection.
Not every lightning strike starts a fire â moisture, fuel continuity, and strike polarity all play a role. Fire Aware maps historical lightning-fire pairs so you can see the spatial pattern in your area. Check the Fire Records page for lightning ignition frequency by region.