I wasn't backpacking but I was working as a Forest Service timber cruiser in the woods of western Oregon when the Columbus Day storm of 1962 came through with winds well in excess of 70 mph. We were working, and camped, in an area where, we later learned, almost all of the standing trees blew down.
We had virtually no warning of the storm other than the steadily increasing wind that eventually made us decide to get out. By this time, trees were falling all around us. By the time we left the work site, blown down trees were completely blocking the road out for as far as we could see.
Our decision was to go back to a recent clearcut and try to set up camp there and wait for it to blow over. Since the only level place on the clearcut was the landing we set up there. We were not in real danger from falling trees but had to deal with a lot of small stuff blowing around and our tent flapping and trying to blow away.
The next morning, after the storm had passed, we explored the possibility of driving out; about 35 miles of Forest Service road. We were not in radio contact with the Ranger District. It soon became obvious that there was no way to get a truck through the blowdown. We decided to wait a day before walking out. Glad we did because the District Ranger sent a helicopter to take us out from where we were camped. It was nearly a year before the road was cleared for vehicle traffic.