The weather tug-of-war is shifting and our natural air conditioning is gaining ground. The marine layer has deepened to around 1,000–1,500 feet, sending fingers of thick fog into the interior valleys. The Forecast: Day-by-Day Tonight: The fog is expanding. Stratus is already hugging the immediate coast, moving through the Golden Gate toward Berkeley. Expect a gray, souggy blanket to fill most inland valleys by early Friday morning . Friday Afternoon: Temperatures begin to drop across the board. The coast stays crisp in the upper 50s to low-60s, while inland valleys drop from the 90s back into the upper 70s and mid-80s. The Memorial Day Weekend: The marine layer deepens even further to 1,500 feet. Expect seasonal, comfortable temperatures alongside the threat of late-night and early-morning coastal drizzle.