1-minute Mesoscale Domain Sector GOES-17 (GOES-West) “Red” Visible (0.64 µm), Shortwave Infrared (3.9 µm), “Clean” Infrared Window (10.35 µm) and Fire Temperature RGB images (above) revealed that the Cougar Peak Fire in southern Oregon produced a pair of pyrocumulonimbus (pyroCb) clouds— denoted by cloud-top 10.35 µm infrared brightness temperatures of -40ºC or colder (with the coldest being -64.9ºC at 0047 UTC) — late in the day... Read More