Given how many stories I see here and on other websites, I'm surprised more people don't disappear or die from exposure. I have read posts on VFTT (Views from the Top, a NE site) about hikers who come across unprepared tourists in winter on a regular basis. Some do wind up needing to be rescued.

Hikers get rescued fairly often in the local (San Gabriel) mountains because they have no water, no light, no skills and no clue as to where they are going.

I remember doing a day hike near Idylwild (up above Palm Springs) and getting caught out as it was getting dark without a light. We weren't that far from the car, but I haven't done that again.

Winter hiking is a whole other story, but I don't go day hiking in winter (on snow) without enough gear (clothes, bag, stove, food and of course, my shovel) to bivy overnight. Depending on where I am, I'd probably take my snowshoes as well, just in case. When I was in Yosemite up around Badger Pass, if I planned to be out of site of my tent for the day, I took my day hike gear with me.

One more thing-a lot of people could save themselves a lot of grief if they just checked the weather. i saw a story on Dateline or one of those shows about a couple who were up around Tahoe in winter,drove around a closed gate, got stuck in heavy snow, a storm came in, the guy tried to walk out and later so did the woman. She found his body down the road a ways and lucky for her, relatives figured out where they might have gone and found her before she froze to death too. All preventable.