![\"Himawari-8](\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2019\/03\/190301_himawari8_visible_Australia_pyroCb_anim.gif\")
<\/a>Himawari-8 “Red” Visible (0.64 \u00b5m)<\/em> images [click to play animation | MP4<\/strong><\/a>]<\/p><\/div>Large bushfires burning in the southern portion of the state of Western Australia produced three pyroCumulonimbus<\/strong><\/a> (pyroCb) clouds on 01 March 2019. JMA<\/strong><\/a> Himawari-8 “Red” Visible (0.64 \u00b5m) images (above)<\/strong> <\/em>showed that the pyroCb clouds drifted southeastward after formation.<\/p>\n Himawari-8 “Clean” Infrared Window (10.4 \u00b5m) images (below)<\/strong><\/em> further revealed the 3 distinct pyroCb pulses — 2 originating from the southernmost fire located near 29.5\u00baS \/ 124.4\u00baE, and a smaller one originating from a fire located farther to the northwest. Cloud-top infrared brightness temperatures cooled to the -59 to -63\u00baC range for the pair of larger pyroCbs (which was close to the tropopause temperature of -64\u00baC on Perth soundings: plot<\/strong><\/a> | data<\/strong><\/a>) with temperatures reaching -51\u00baC with the smaller northernmost pyroCb. Also apparent was a surge of cooler air moving northeastward behind a surface trough<\/strong><\/a>, whose arrival appeared to coincide with the pyroCb formation. A time series of surface data from Forrest (YFRT<\/strong><\/a>) clearly showed the arrival of the cool, moist air behind the trough.<\/p>\n Himawari-8 “Clean” Infrared Window (10.4 \u00b5m)<\/em> images [click to play animation | MP4<\/strong><\/a>]<\/p><\/div> Suomi NPP VIIRS True Color RGB and Infrared Window (11.45 \u00b5m)<\/em> images at 0537 UTC [click to enlarge]<\/p><\/div>As shown using RealEarth<\/strong><\/a>, an overpass of the Suomi NPP satellite provided a more detailed view of the first (and<\/em> largest)<\/em> pyroCb at 0537 UTC (above)<\/strong>, <\/em>with NOAA-20 capturing the second pyroCb cloud about an hour later at 0628 UTC (below)<\/strong><\/em>. The coldest cloud-top infrared brightness temperature on the 0537 UTC Suomi NPP VIIRS image was -70\u00baC (darker black enhancement);<\/em> in addition, there appeared to be an Above-Anvil Cirrus Plume<\/strong><\/a> associated with that pyroCb, extending southeastward from a subtle Enhanced-V signature<\/strong><\/a> at the upshear (northwestern) edge of the cloud (where the warmest temperature was -48\u00baC, green enhancement)<\/em>.<\/p>\n NOAA-20 VIIRS True Color RGB and Infrared Window (11.45 \u00b5m)<\/em> images at 0628 UTC [click to enlarge]<\/p><\/div>On Himawari-8 Shortwave Infrared (3.9 \u00b5m) images (below)<\/strong>,<\/em> the pyroCb clouds exhibited a warmer (darker gray)<\/em> appearance compared to adjacent conventional cumulonimbus clouds — this is due to the fact that ice crystals ejected into the pyroCb anvils are smaller<\/em> (due to their shorter residence time within the intense updrafts above the fires), and these smaller ice crystals are more effective reflectors of incoming solar radiation. The large flare-up of red-enhanced land during the day is due to highly reflective soils of the Great Victoria Desert that quickly become very hot.<\/p>\n<\/a><\/a><\/a>