Across Memphis, the summer sun bakes deck boards hard enough to open the grain, and once that happens, every storm throws a layer of grit across the surface that works like sandpaper under foot traffic. Loess soil underneath many decks holds onto moisture, and that vapor pushes upward into posts and lower boards, lifting older finishes from the inside out. Shady yards in neighborhoods like High Point and Berclair stay damp longer, which exaggerates mildew growth and softens thin coatings. Seasonal swings — bright UV peaks, sudden cold fronts, and extended humid nights — break down stains faster here than in drier parts of the country. We usually grab high-solids exterior stains and composite-friendly brushes from local Memphis suppliers like Sutherlands or the Poplar Home Depot to keep finishes holding up longer.