Explosive eruption of Mount Shishaldin in the Aleutian Islands of Alaska
GOES-18 Ash RGB images (top) and SO2 RGB images (bottom), with plots of Pilot Reports and Volcanic Ash Advisory/Forecast polygons, from 1250-1910 UTC [click to play animated GIF | MP4]
2 Pilot Reports (PIREPs) issued shortly after the eruption onset indicated an ash height of 21000 ft at 1400 UTC, and 40000 ft at 1446 UTC (below).
GOES-18 Ash RGB (top) and SO2 RGB (bottom) images at 1400 UTC, with cursor sampling of a of Pilot Report issued at 1400 UTC [click to enlarge]
GOES-18 Ash RGB (top) and SO2 RGB (bottom) images at 1450 UTC, with cursor sampling of a of Pilot Report issued at 1446 UTC [click to enlarge]
GOES-18 Nighttime Microphysics RGB + daytime True Color RGB images, from 1210-2140 UTC [click to play MP4 animation]
Volcanic Cloud Ash Height derived product, from 1330-1700 UTC [click to play animated GIF | MP4]
Suomi-NPP VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images, valid at 1404 UTC [click to enlarge]
The -64.37ºC cloud-top infrared brightness temperature was indicative of a significant air parcel overshoot of the local tropopause — which was -50.5ºC at an altitude of 9292.4 m (30486.9 ft) according to 1200 UTC rawinsonde data from nearby Cold Bay, Alaska (below).
Plot of rawinsonde data from Cold Bay, Alaska at 1200 UTC [click to enlarge]
Infrared Window images from Suomi-NPP (11.45 µm, valid at 1404 UTC) and GOES-18 (10.3 µm, valid at 1401 UTC) [click to enlarge]