Did You Know: Summer Fog in San Francisco Isn’t What It Used to Be?

By theFrontSteps Real Estate on April 11, 2025 • ( Leave a comment )

San Francisco’s famous fog has been fading over the years, and science points to climate change as the reason. Studies show summer fog has decreased by about a third since the early 1900s, with the most noticeable drops happening in recent decades. Warmer ocean temperatures and shifting weather patterns make it harder for fog to form, meaning fewer of those classic chilly, gray summer days.

This change affects more than just the city’s character. The fog provides essential moisture for San Francisco’s urban forests, including the towering redwoods in Golden Gate Park and Mount Sutro that depend on its drip during dry months. Street trees and backyard gardens also feel the difference as summers grow warmer and drier without the fog’s cooling blanket.

Even the cultural ritual of naming the fog (like “Karl”) might become less meaningful if the trend continues. Next time you notice a clear summer sky where you’d expect fog, it’s not just a fluke – it’s part of a measurable change in the city’s microclimate, with consequences for both nature and daily life in San Francisco.

Bet you didn’t know that… or maybe you did.