08/19/2025
When we are giving updates on a wildfire, one of the first things you hear is how big it is.
Those numbers can sound massive, hundreds, thousands, even hundreds of thousands of hectares. It’s easy to imagine that all of that is actively on fire.
But here’s the thing, the size is the outline of the whole area the fire has touched. Inside that outline some spots are still burning, and others are just blackened ground where the flames have already passed.
We track and provide the size based on the outline, or “fire perimeter,” because we want everyone to know where the fire’s edge is, and stay well away. Even after fire has stopped actively burning, these areas can continue to smoulder and are not immediately safe.
You can also think of it like a colouring book, the size in hectares is the whole page, but the flames are only colouring in certain spots right now. A fire might be 100 hectares, but at the moment maybe only 10 are actually burning.
The photo below shows how only some parts are currently burning but the size of the fire would also include the black areas you can see.
So if you hear the fire has grown, remember it doesn’t mean the entire area is on fire at once and doesn't tell the whole story.
