I was 8 years old when the mountain blew. I can barely recall the perfectly symmetrical, snow-capped peak from my childhood (America's Mt. Fuji, they said...) most often glimpsed as we were driving across the I-5 Marquam Bridge through downtown Portland on the way to my grandmother or aunt's house in NE Portland. This is the image I recall, from 1977:
And this is what was seen a month after the eruption, in 1980:
From our vantage point to the south it just looked like a giant had sliced the top off as if it were a a soft boiled egg. And the elegeant old lady was quietly, literally fuming like a cartoon character. But to the north where the massive landslide and lateral blast occurred it was another story.
Before from Spirit Lake:
After from Spirit Lake (1982):
I've camped, and hiked, and explored in the Gifford Pinchot national Forest on the south flank of the mountain for years, but I still have never made it up to the Johnston Ridge Observatory. I think the Monkey and I are long overdue for a visit this summer.
Some media retrospectives: MSNBC slideshow,