Fire Cloud with a Pileus on Top

What happened

Scientists captured rare observations of an ephemeral pileus cloud hovering over a smoke-infused cloud that rose above a wildfire in Montana. In the false-color image (right) active fires appear pink and yellow, burned areas brown, clouds white, and smoke blue-purple.

MASTER images by RoseAnne Dominguez, annotated by Michala Garrison. In summer 2026, scientists took to the air to intercept and study the towering, smoke-infused clouds that wildland fires sometimes create.

But during an August 11 flight over the Sand Creek fire in Montana, they came back with a bonus—observations of an ephemeral pileus cloud hovering atop one of the towering fire clouds. Smooth, veil-like pileus clouds are well-known to atmospheric scientists and cloud lovers and regarded as signs of especially vigorous convection .