Towards sunset a pyroCb formed in Cecil Plains in Queensland, Australia. Starting at 7:00 UTC on 05 December, the animation below (also available as an MP4) shows Himawari-8 0.63 µm visible (left) and 3.9 µm shortwave IR (right) . The pyroCb cloud (~28.2º S, 151ºE) formed around 7:50 UTC. In the shortwave IR images, the red pixels indicate very hot IR brightness temperatures exhibited by the fire source regions.

Himawari-8 0.63 µm visible channel (left) and 3.9 µm shortwave IR channel images (right) (click to play animation).
In addition, the Himawari-8 10.4 μm IR channel allowed the cloud-top IR brightness temperature to be measured. The animation below, also starting at 7:00 UTC on 05 December, shows that the brightness temperature for the pyroCb cloud reached roughly -59ºC at 9:10 UTC (red color enhancement).
1-km resolution POES AVHRR images (below; courtesy of René Servranckx) showed pyroCb cloud-top IR brightness temperatures as cold as -66.6º C at 8:39 UTC.
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POES AVHRR Shortwave Infrared (left) and Infrared Window (right)