The couple got lost, then she apparently succumbed to heat stroke. Story here. As is common in the wilderness it was not a single element but a group of elements (lost, heat, physical condition, perhaps more) together that spelled disaster. This story strikes home to me because I have been a heat casualty and it is no fun.

Stay safe out there this summer, folks.

In a different article I read about this incident, a ranger was saying that everyone seems to the get to the spot OK. It's on the return trip that people typically get lost. So, finding a destination easily is no guarantee that the return route will be as easy.

Permits are required to hike to there and they are limited in supply and given out by lottery. Apparently you have little control over when your application might be approved, so even if it's the hottest part of the summer, people still make the trek because they don't know when they might get another chance.

I'll take our cold weather over the desert heat any day. It's so much easier to warm up than to cool down. We lost one of the residents of our townhouse community on the weekend due to the exact same thing, cardiac arrest due to heat exhaustion. And she was just sitting around the pool watching her grandson swim. Honestly, deserts are probably the environment that scare me the most. If you get lost, and can't find water, you're screwed.

Your post seems to explain why they were hiking at lower elevations during this time of year. This is the time when I head for higher, cooler ground. Deserts are for winter or spring.

Based upon the wikipedia article, heat injury is very complex. The straightforward dehydration/heat exhaustion is only one piece of the puzzle. Elevated body temp damages the intestines ability to contain contain endotoxins, portions of bacterial cells that are toxic in themselves as distinct from toxins produced by bacteria, resulting in toxic shock and damage to diverse organs. High body temp resulting from exertion in high heat environments can start a cascade of devastating physiological events that can kill very healthy people very quickly: Michael Popov's last run.. This seems to be simple physics-generating more heat than can be dissipated, but the wiki article suggests that high heat/high humidity environments may result in scenarios that are fatal to people resting in front of a fan in the shade. Scary stuff.

Good points NurseMike. I had seen the stories on Popov and that was quite sobering.

I've seen some material from US Army research that shows heat illness to be a somewhat inflammatory response, not just a heat transfer problem, and that aligns with your post. The Army has found that heat stress is cumulative, and making it through the night after a hot day is no guarantee of surviving the next day's heat.

Like BacPacJac says, if I stay on top of things I can stay warm in the cold, but even if I do everything right I can't make a lethally hot environment cooler.

Generally, heat is the number one weather related killer. The '95 heat wave in Chicago killed about 750 residents in five days, mostly older folks just trying to ride out the heat at home. They certainly weren't exerting themselves heavily during that week.