Think of it as a giant bubble filled with wildfire smoke.
Korri Anderson with the National Weather Service in Boise says the pyrocumulus cloud over the Pioneer Fire is the result of moisture being released from burning trees and brush. He says these kinds of clouds -- which can reach 35,000 feet -- develop in the afternoon when the conditions are just right. He says like normal clouds, pyrocumulus formations need the correct combination of temperature and humidity to form. But once they do, they can come with their own weather system, with wind and dry lightning that could complicate firefighting efforts.
Anderson says so far the pyrocumulus cloud from the Pioneer Fire has not created any lightning, and that once the temperature from the wildfire dies down, the formation will dissipate. But until then, be sure to look out the window on your next flight to or from Boise for a birds-eye view of this weather phenom.
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