I'm home safe but still a little shook up. Tom and I were on our way home this afternoon after having done a short mountain hike in northern Washington, driving at a pretty good speed down the Mount Baker Highway; we had just passed the Nooksack North Fork Beer Shrine (which, judging by the number of cars parked in front of it, was full of worshipers). That stretch of road has forest on both sides. Tom was at the wheel, and I was relaxed from the hike, gazing dreamily out the front window. Not far ahead, a tall skinny tree on the right side of the road tilted, as though it were breaking out of the pack of trees, and then just kept falling down, down, down. I watched the fall as though it were in slow motion. Really, I could hardly believe my eyes. At around the time the tree had gotten about halfway down, I realized that it was going to land on us.
In fact, though, the tree (likely a Douglas Fir) didn't hit it us (as you must already have realized, since I'm now writing this). Tom saw it at about the halfway point and braked (debating with himself just how hard to brake). As a consequence, we hit the tree instead of it hitting us, at a speed of about 20 mph, and bounced more than once and then limped off to the side of the road, our car making the sound that cars make when one is driving on the wheel rim. No one, I'm happy to report, was close behind us. The first vehicle behind us arrived a few minutes later and stopped to check on us as we were examining the car. They thought that a logging truck must have dropped a portion of its load and neglected to stop to retrieve it.
The right wheel was wrecked. Tom says that when he removed it to put on the spare, it was hot: it had absorbed most of the shock of the collision. I looked under the car and saw neither drips nor anything hanging down or obviously ruptured. (I was worried that the axles might have been damaged, or worse.) My theory is that the tree fell at a slight angle across the road, not exactly perpendicular to us-- to our great good fortune, since we would have lost both wheels if it had been straight across the road and would likely have flipped over if it had fallen at more of an angle than it did.
We won't know how much damage the collision did until we take it to our regular mechanic. But the car was vibrating in a disturbing fashion, so we took the backroads, avoiding the interstate so that we could drive at low speed and occasionally pulling over to the side to let faster drivers pass us.
All the way home a little film-loop kept playing in my head, of that tree falling. Now I'm drinking a glass of wine and feeling much better. But that dry, rotten tree is still falling in my mind.
PS The airbags didn't inflate, for which we were profoundly grateful.
ETA: As might be expected when one's car bounces over a downed tree, the car took a lot more hurt than to the wheel: that was only the most visibly damaged. All sorts of things, most prominently the oil pan, need replacing. And the mechanic says we were lucky only the front end of the car took the hit...