John Polyniak of Lake Shore says that in late fall, it often gets cold and frosty just before a warm front arrives. "Why?" he asks. Steve Zubrick, an NWS science officer, says it's a cycle. A cold front passes by, temperatures drop. High pressure moves in, skies clear, winds calm, frost forms. Then the high moves east, allowing the next low to approach. It drags in a warm front, just ahead of the next cold front. Cycles.
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