I think I must have had punctures ("flats" to you Neighbours to the South) every day now for the past several days. I even had both tires go on one ride.
When it starts raining here in the Vancouver area, all sorts of debris gets washed onto the road shoulder, right where I'm riding. So I have to be more vigilant and dust the tires more often.
As well, the sidewalls start to fail near the bead as the sidewalls on older tires start to rot. I had the front tire pop on me yesterday. I heard the explosion of the tube and then the front of the bike felt dead.
But at least it's still warm enough to replace the tube. The worst time to have a puncture is when it's around freezing, and rain is falling, and you can't get your fingers to work, and the sweat is starting to make you feel very cold.
The other sign of fall/winter is the brake blocks start wearing. I've gone all summer without having to replace the brake blocks. I think I've got at least 5,000 km on them. These same blocks will only last a few weeks in a typical Vancouver winter. I must go thru about four or five sets of brake blocks each winter (and then one set all summer). And the wet, gritty blocks tend to grind down the rim braking sufaces. I think I get about three years on each rim before it stats to crack, or the top of the rim gets deformed (pushed out by the pressure in the clincher tire). The interesting part is trying to figure out when the rim is going to fail. I've had rims crack, with resulting blowout as the tire bead comes off the rim and the inner tube has nothing holding it at 120 lbs. I've ridden home on wrecked rims with shredded tires. You want to make sure you get every last kilometer out of the rim...