NASA captures a rare pileus above a wildfire cloud

NASA has published airborne observations from August 11 over Montana's Sand Creek fire, where a smooth, short-lived pileus cloud formed above a rapidly developing pyrocumulus. Pileus typically appears when a powerful updraft lifts a moist layer overhead until it cools and condenses, but detailed observations of interaction with a fire cloud are rare. The MASTER instrument aboard a high-altitude ER-2 aircraft captured visible and shortwave-infrared information across fifty spectral bands, joining active fire, burn scar, smoke plume and cloud structure. The pileus was clearly visible in only one scene among images collected roughly thirty minutes apart, pointing to extreme updraft dynamics. The INSPYRE campaign observation improves process understanding from fire behavior to convective plume; it is not a new operational forecast product.