When the Oregon Gulch fire blew up near Ashland, there was an awe-inspiring cloud that formed in the area of the fire.
It looked like a thundercloud, but it was boiling up like smoke. There was plenty of dark smoke, but that cloud was too white to be all smoke. What were we seeing?
— Joyce, Medford
The dramatic, cauliflower-shaped cloud you spotted was a pyrocumulus cloud, also known as a “fire cloud.”
Marc Spilde, Medford weather service meteorologist, said pyrocumulus clouds form from the intense heat generated by the fire.
“It basically forms into a towering cumulus,” Spilde said. “But the very hot surfaces and the cooler air aloft create a lot of instability.”
The pyrocumulus cloud you spotted in the Oregon Gulch fire was large enough to loft a large amount of smoke into the atmosphere and cause several lightening strikes.
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