Bay Area/ San Francisco/ Weather & Environment

Karl the Fog Crashes San Francisco’s Late-Summer Heat Party as Temps Dip Into Weekend

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Published on August 20, 2026
Karl the Fog Crashes San Francisco’s Late-Summer Heat Party as Temps Dip Into WeekendSource: Brocken Inaglory, CC BY-SA 3.0, via Wikimedia Commons

San Francisco is waking up today to a cool, cloud-covered morning around 56 degrees, with the thermometer headed only to 67 by afternoon. The city is beginning a gradual cooldown that will trade recent warmth for classic late-summer Bay Area weather: low clouds, brighter breaks, and a steady breeze.

Clouds Clear Somewhat, Then Fog Rolls Back In

Today will stay mostly cloudy, with temperatures climbing into the low and mid-60s around midday before easing back in the late afternoon. The National Weather Service says the marine layer will deepen, pushing low clouds farther inland after sunset and likely bringing another gray start Friday.

Afternoon Winds Pick Up

West-southwest winds will run 6 to 14 mph today, with gusts reaching 21 mph. That could make waterfront walks feel brisk, while the tiny rain chances — 2% or less — leave umbrellas mostly unemployed.

Weekend Weather Stays Mild

Tomorrow should be partly sunny with a high near 68, followed by 69 on Saturday and 70 next Sunday. Overnight lows will remain near 58, while west and west-southwest winds continue at roughly 5 to 15 mph.

Cooler Again Next Week

The forecast eases back to highs around 65 next Monday and Tuesday, then nudges up to 67 next Wednesday. Nights will remain mostly cloudy with lows around 57 to 58, and no meaningful rain is expected through next Wednesday, August 26.