Heat is definitely a factor, but I've lived in southern Nevada now for more than 25 years. I know and respect the heat. The scary thing here is just how quickly you can get into trouble. Thanks to evaporative cooling, you don't feel that hot so long as you can still sweat. But you can get into trouble really fast once you pass a point.

But that's one reason why I try to get out and be on the road no later than 9am, and earlier is even better. Like this morning, I was on the bike just after 8am. Had things gone to plan, I likely would have been back before 10:30, even if I had done the full 40 miles. But even cutting it short, I still finished around 10:30. It's hot by then but a far cry from how hot it's going to get by 4 this afternoon.

I do admit I'm really bad about hydration. It's something I know I need to work on, but particularly when I'm working around the house, or just generally at work, I forget to drink regularly. Before I know it, I've gone 2-3 hours without any water intake at all.