The eruption that produced this famous image (R. Clucas/Alaska Volcano Observatory [AVO] via Wikimedia) began. Despite appearances, this Alaska volcano didn't go nuclear; it was "just" a VEI 3 eruption per the Global Volcanism Program.
Still, it had a lot of influence:
- It the second most costly eruption in US history, at least per Wikipedia.
- It's also famous for being the first time the forecast significance of what's known as long-period tremor was recognized (AVO issued their first ever eruption forecast on the 13th -- yeah, they got it right!).
- There were so many mudflows/lahars that a warning system was developed for these; the current iteration of this technology is in place now on Mount Rainier and other known lahar-prone dangerous volcanoes.
- This is the one where that jet almost crashed after "inhaling' volcanic gas. What I didn't know until today was that there were six other encounters with the ash cloud, two of them over Texas! This was not the first trouble aircraft had with volcanic ash during the 1980s, and soon VAACs became a thing.
As far as I can tell, there were no human fatalities from the eruption. That's something else we should hear this tragic week.