They were in storage. Since I'm commuting 100 miles a day now, I decided to take them off so they don't get abused. And since I put better tires on those, they don't last very long with this commute.

We get lots of rain here h:

Nope everything's straight.

I think the inside sidewall might have had a bulge on it. I had started to get a vibration at freeway speeds recently, which I figured was just an axle getting pitted from being so low for so long. My guess is the inside had a bulge which finally blew (there's a quarter sized hole on the inner sidewall) which then caused the bigger blowout on the outside. But this is all speculation. When the vibration started I checked air pressures which were fine, outer sidewall was fine, tread was worn pretty evenly. So who knows at this point. The tire is so far gone I really can't tell much.

After it blew, it looks like the wheel stuck in position and just slid, because it is crazy flat spotted near the big hole, and all the way to the steel belts.