I was living in Kennewick, Washington when Saint Helens blew. Being east of the Cascades the weather is always sunny and clear there, and when I woke up that morning, deeply hung over, I walked out of my apartment to drive to get coffee at the convenience store and instantly saw the several inches of ash covering the ground and my car.
Giant, dark rolling clouds filled the sky, and I instantly assumed there had been a nuclear war, that the ash was fallout, and I would go back inside and turn on the TV and figure out when I would die from radiation. It was quite the relief to realize it was only a volcano natural disaster.
One thing nobody talks about now was that the ash fell in such fine particles that everyone’s radiators immediately became clogged and cars overheated, and had to stop. I was a court administrator for the Benton Franklin County Superior Court at the time, and trials were conducted in the town of Prosser about 20 miles away, as they were the county seat. It took many weeks before people could drive 20 miles and not have their cars overheat. This included most first responder vehicle vehicles as well. It was definitely a thing that impacted everyone in the state for a while if they were in the plume penumbra.