"snow squall" 1828, American English; earlier with a sense of "commotion, state of perturbed action" (1710), "a gust, a squall" (1690s); perhaps imitative, or else from 17c. flurr "to scatter, fly with a whirring noise," which is perhaps from Middle English flouren "to sprinkle, as with flour" (late 14c.).
1757, "produce agitation of feeling in, confuse by excitement," from flurry (n.). From 1883 of snow. Related: Flurried; flurries; flurrying.