As West Pacific Tropical Depression 02W — previously discussed in this blog post — intensified to become Tropical Storm Mawar at 1200 UTC on 20 May 2023, 2.5-minute rapid scan JMA Himawari-9 “Clean” Infrared Window (10.4 µm) images (above) showed pulses of cold overshooting tops that frequently exhibited infrared brightness temperatures in the -90... Read More
GOES-18 (GOES-West) “Clean” Infrared Window (10.3 µm) images (above) showed the formation of a pyrocumulonimbus (pyroCb) cloud — produced by a wildfire southwest of Fort Nelson, British Columbia (station identifier CYYE) — around 2340 UTC on 19 May 2023. Cloud-top infrared brightness temperatures reached -61ºC as the pyroCb cloud drifted eastward across Alberta.GOES-18 True... Read More
Southern Wisconsin experienced the convergence of 3 cooling mechanisms during the afternoon hours of 16 May 2023: (1) the arrival of a dense band of smoke aloft — transported southward from wildfires in Alberta and Saskatchewan — which reduced incoming solar radiation, (2) a southward-moving cold front and (3) the inland surge... Read More
JMA Himawari-9 Infrared Window (10.4 µm) images of Cyclone Mocha in the Bay of Bengal on 13 May 2023 (above) displayed cold clouds surrounding an eye that gradually became more cloud-cleared — with isolated cloud-top infrared brightness temperature values of -90ºC and colder (yellow pixels embedded within dark purple regions).... Read More
