Cloud Wearing a 'Hat' Above Fire: NASA Captures Rare Atmospheric Phenomenon

Scientists from NASA captured an unusual atmospheric phenomenon above the Sand Creek fire in Montana, United States: a thin, cap-like cloud that appeared above a towering pyrocumulus cloud rising from smoke and heat. The agency described the image as one of the rare instances observed with such clarity.

According to NASA’s Earth Observatory, the images were taken on August 11 during a scientific flight as part of the INSPIRE campaign, a mission dedicated to studying clouds generated by wildfires.

The team used the MASTER instrument mounted on the high-altitude ER-2 research aircraft to observe the scene at 5:40 p.m. local time.

The upper cloud, known as a pileus (from the Latin word for “cap”), forms when a strong updraft collides with a moister air layer above it, pushing it upward where the air cools and water vapor condenses. The larger cloud beneath it is a pyrocumulus cloud, which develops from the heat and smoke of a fire.

Notably, this type of upper cloud is extremely short-lived, often persisting for only a few minutes. NASA noted that the cloud was clearly visible in just one frame among a series of consecutive images captured by the team, giving the photograph special scientific and visual value.

The fire’s own context underscores the intensity of the scene: official updates from Montana indicated that the Sand Creek fire was expanding rapidly at that time, explaining the strength of the updrafts that created this rare atmospheric “cap.”