Think about how hemingway uses the change of seasons from late summer to autumn and winter.
The mood and the tone have an ominous sense to them. It is late summer and the life created in the spring is withering. It is the harbinger of something more sinister that travels along the dusty roads of village. The narrator tells us that man has even marked the trees with dust kicked up from the boots of soldiers and the tracks of trucks holding guns. We notice the season has progressed to fall not by the gentle mountain winds but rather by the "flashes from the artillery. In the dark it was like summer lightening..." There is more war imagery and by winter the narrator talks about the arrival of Cholera. He notes that only, "seven thousand died of it in the army." THis is some chilling foreshadowing for that number will be insignificant to the toll taken by this war. The winter is the beginning of a long and bloody chapter in history.
