3-Day Fog Forecast

The Golden Gate Bridge fog forecast predicts hour-by-hour visibility at the bridge for the next 72 hours, updated every 15 minutes using Open-Meteo weather data from the bridge's exact coordinates (37.8199°N, 122.4783°W). San Francisco's famous fog — affectionately known as Karl — is primarily advection fog, formed when warm, moist air from the Pacific Ocean passes over the frigid waters of the California Current. As this air cools below its dew point, moisture condenses into the thick marine layer that frequently envelops the bridge.

Our hour-by-hour forecast uses data from the Open-Meteo high-resolution weather model, updated every 15 minutes, to predict visibility conditions at the bridge's exact coordinates (37.8199°N, 122.4783°W). We classify each hour into three categories: Clear (visibility above 5 miles with low cloud cover), Partly Visible (visibility between 1 and 5 miles or moderate cloud cover), and Fogged In (visibility below 1 mile or heavy cloud cover above 85%).

Fog patterns at the Golden Gate are highly seasonal. Summer months (June through August) see the most fog, driven by the strong temperature contrast between cool coastal air and hot inland valleys. The fog typically rolls in during the late afternoon and evening, lingers through the night, and burns off by late morning. September and October are often the clearest months, making them the best time to photograph the bridge. Winter fog is less frequent but can be accompanied by rain and reduced visibility from precipitation.

Wind speed plays a crucial role in fog behavior. Moderate westerly winds push the marine layer through the Golden Gate strait, while strong offshore winds can keep the fog at bay. Our forecast includes wind data so you can gauge whether conditions will improve or deteriorate over the next 72 hours. For the most reliable visit, check this forecast early in the morning and look for windows of clear conditions.