PORTLAND, Ore. — Smoke and heat from the massive Bootleg Fire in southern Oregon are creating so-called fire clouds over the blaze. Those are dangerous columns of smoke and ash that can reach up to 6 miles in the sky and are visible from more than 100 miles away.
These clouds are especially dangerous because they can collapse and cause hot winds and embers to fall on firefighters working below.
An even more extreme type of fire-induced cloud that can can create its own weather also formed over the Bootleg Fire this week. In a worst case, those spawn fire tornadoes and generate their own lightning.
The Bootleg Fire is the largest wildfire in the nation at more than 241,000 acres.
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