These are the opposites of conspicuous:
inconspicuous unnoticeable unnoticed obscure obscured indistinct hidden concealed unobtrusive camouflaged indiscernible invisible imperceptible unseen unclear ambiguous vague unapparent indefinite unremarkable unflamboyant unemphatic unshowy equivocal nonobvious obfuscated cryptic mysterious clouded uncertain
Answer:
probably early snows- if it got too snowy they could get stuck or be unable to go through the pass if it got too deep
