The cold, harsh environment relates to the meaning of the story of this existentialist work because of the way in which the snow, which has covered the landscape and made it impossible to navigate or to see any signposts, is representative of the way that any moral code has been covered over or dispensed with between these three friends. Note for example the following paragraph that makes reference to the way that the snow has covered up the landscape around them:
They left Spokane and drove deep into the country, running along black lines of fences. The snow let up, but still there was no edge to the land where it met the sky. Nothing moved in the chalky fields. The cold bleached their faces and made the stubble stand out on their cheeks and along their upper lips.
As the landscape has been covered up, both literally and metaphysically, the characters are free to operate without any moral code whatsoever. This is shown in particular with the relationship that builds up between Frank and Tub. Male bonding is shown to be taken to its absurd extreme. Frank and Tub are so pleased with the friendship that they are developing, and the freedom that they have to be honest with each other, that they view this burgeoning friendship as being more important than the life of Kenny, who is slowly dying in the back of the vehicle. The way that at the end Frank drives in the opposite direction of the hospital and they give away the blankets that were covering Kenny does not bode well for Kenny's future. The weather therefore signals to the reader that the characters are plunged in a world without any moral signposts, just as the literal signposts have been covered up by the snow. It is a world where anything goes, and absurdity rules.