Good post. Really tragic.
It looks like they didn't have enough protection - then tried to make it out quickly when things went bad.
But the rain and the cold "won the race" against body energy.

I always carry a daypack, warm jacket and flashlight.
But i admit that I'm spoiled in CA and often don't carry a Bic lighter, matches or a tarp. I will add them ... because basically that's no weight at all.

I do have a SPOT2 device and always have that with me when I'm outdoors these days.

Pete2