PyroCbs in Western Australia

Himawari-8 “Red” Visible (0.64 µm) images [click to play animation | MP4]

Himawari-8 “Clean” Infrared Window (10.4 µm) images (below) further revealed the 3 distinct pyroCb pulses — 2 originating from the southernmost fire located near 29.5ºS / 124.4ºE, and a smaller one originating from a fire located farther to the northwest. Cloud-top infrared brightness temperatures cooled to the -59 to -63ºC range for the pair of larger pyroCbs (which was close to the tropopause temperature of -64ºC on Perth soundings: plot | data) with temperatures reaching -51ºC with the smaller northernmost pyroCb. Also apparent was a surge of cooler air moving northeastward behind a surface trough, whose arrival appeared to coincide with the pyroCb formation. A time series of surface data from Forrest (YFRT) clearly showed the arrival of the cool, moist air behind the trough.

Himawari-8 “Clean” Infrared Window (10.4 µm) images [click to play animation | MP4]

Suomi NPP VIIRS True Color RGB and Infrared Window (11.45 µm) images at 0537 UTC [click to enlarge]

NOAA-20 VIIRS True Color RGB and Infrared Window (11.45 µm) images at 0628 UTC [click to enlarge]

Himawari-8 Shortwave Infrared (3.9 µm) images [click to play animation | MP4]