In May 1980 when Mt. St. Helens blew, we lived in Pullman, about two hundred miles downwind. We ended up with eight tons of ash per acre. Everything was tied up for days, all the legal authorities were telling everyone to limit travel to necessary business. The highways were closed to everything except emergency traffic.
The local elders called Brooklyn to get permission to cancel the meetings, at least that is what I was told when I got the phone call. You'd common sense would have been all they needed, but I guess that's asking too much.