In that first paragraph we are given the setting of the story (Yukon, 9 o'clock and we only know its daytime b/c it says that it was a "clear day" but with "no sun, or hint or sun"). We also get the atmosphere (dark, no sun, 50 degrees below zero, and getting colder). And there is also foreshadowing: The day felt gloomy, no sun for a few days, and the man was already panting as he was walking to meet his cronies over at the campsite. When he looked at his watch, I feel, it was also foreshadowing and metaphor that "his clock is ticking" as well.
Hope this helps!