Pyrocumulonimbus clouds in Australia
2.5-miute Rapid Scan JMA Himawari-8 “Red” Visible (0.64 µm), Shortwave Infrared (3.9 µm) and Infrared Window (10.4 µm) images (above) showed the formation of 2 small, fairly short-lived pyrocumulonimbus (pyroCb) clouds spawned by large, hot bushfires in southern New South Wales, Australia on 01 February 2020. The pyroCb clouds developed in advance of an approaching cold front (surface analyses), exhibiting 10.4 µm cloud-top infrared brightness temperatures in the -40 to -49ºC range (shades of blue). The first pyroCb formed at at 0311 UTC to the northeast of Cooma (YCOM), with the second formed at 0559 UTC just southwest of Merimbula (YMER).NOAA-20 VIIRS True Color Red-Green-Blue (RGB) and Infrared Window (11.45 µm) images at 0426 UTC as viewed using RealEarth (below) revealed cloud-top infrared brightness temperatures near -60ºC (darker red enhancement).
A toggle between Suomi NPP VIIRS Day/Night Band (0.7 µm) and Shortwave Infrared (3.74 µm) images at 1454 UTC or 1:54 am AEDT (below) displayed the nighttime glow and hot thermal signatures of large bushfires south and southeast of Canberra.