An unexpected turn of events
Last year I went to the mountains with my friend. It's already been quite late and the summer was soon going to end. We thought that it was high time to go that year even though it was a bit risky. As it turned out later, we weren't prepared for what was going to happen.
We planned our trip for about 6~7 hours on the first day and we were supposed to get to the shelter around 5PM, we couldn't have been more wrong. It was the first snowy day in the mountains and we didn't have the proper gear. Thankfully though, we took warm clothes.
At the beginning the approach was actually quite pleasant, there was a lot of snow but it was sunny and we managed to get to the top of the mountain with just around thirty minutes of delay. The real problems started later, when the blizzard caught us climbing down. It was as slippery as it gets and there was no way for us to go down and reach our destination point. We found a small opening in between of rocks and took our refuge there, trying to find another way on the map at the same time. There was none, we could either go back, which was not a question or go down which would probably end with us falling down, so we stayed there until the night, we waited for the storm to pass.
I don't remember the following hours too well, we took turns sleeping but it wasn't pleasant at all, we just needed more strength. Finally the wind calmed down and we tried to climb down, but the rocks were steep and covered with ice....
...It's merely the beginning of the story! Think what might have happened later, where did the travelers get to, why weren't they able to just sit at the warm shelter, maybe an animal attacked them or one of them twisted their ankle? There are many possibilities, so don't let your creativity be held back by getting ready answers! I'm sure you're more than capable of finishing this story by yourself :)
All the best!