>>2690865>https://en.m.wikipedia.org/wiki/Disappearance_of_Maureen_KellyWeatherspark claims that the area she was in, outside of Portland, can get down to 45F at night in June, with 25% chance of rain.
The terrain is rough, with some of the biggest mountains in the U.S. That can make it tough to go even 5 miles. She had no map. Mountains can form a kind of labyrinth. Even if you're 5 miles away from civilization, it doesn't mean anything if you're stuck in an impassable valley and you can't climb out.
She might even have broken an ankle in that terrain, which makes movement even slower, if not impossible. No emergency phone meant she couldn't call for help.
She was an amateur. She was probably counting on being able to light a fire to keep warm at night without clothes. Getting rained on will suck the heat right out of you, even in June, especially in the shadow of those mountains.
In addition, rain makes it hard for someone inexperienced to light a fire. The hypothesis that she died from exposure seems likely.
Without food or water, the body shuts down rapidly. Maybe she did manage to find water, but she didn't have anything to purify it with, which meant that even if she lived more than a couple days, she might have been delirious from waterborne diseases.
I attribute deaths like this to the Dunning Kreuger effect. She liked being out in the wilderness, and she was pushing her limits, but she didn't have enough experience to know how dangerous her lack of experience truly was.
We have a lot of deaths like this up here on Mount Washington. It's a story that's all too common.