Forecast Details for San Francisco, CA

Recent Locations: San Francisco, CA

Tonight: Mostly clear, with a low around 53. West wind 16 to 20 mph, with gusts as high as 25 mph.

Saturday: Sunny, with a high near 65. Breezy, with a west wind 14 to 23 mph, with gusts as high as 28 mph.

Saturday Night: Increasing clouds, with a low around 52. Breezy, with a west wind 17 to 22 mph decreasing to 10 to 15 mph after midnight. Winds could gust as high as 26 mph.

Sunday: Mostly cloudy, then gradually becoming sunny, with a high near 66. West southwest wind 8 to 18 mph, with gusts as high as 23 mph.

Sunday Night: Mostly cloudy, with a low around 53. West southwest wind 13 to 20 mph, with gusts as high as 24 mph.

Monday: Mostly sunny, with a high near 67.

Monday Night: Mostly cloudy, with a low around 55.

Tuesday: Mostly sunny, with a high near 68.

Tuesday Night: Partly cloudy, with a low around 55.

Wednesday: Mostly sunny, with a high near 70.

Wednesday Night: Mostly clear, with a low around 55.

Thursday: Sunny, with a high near 73.

Thursday Night: Mostly clear, with a low around 55.

Friday: Sunny, with a high near 70.

Want more detail? Get the Complete 7 Day and Night Detailed Forecast!

Current U.S. National Radar--Current

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National Weather Forecast--Current

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National Weather Forecast for Tomorrow

Tomorrow National Weather Forecast and Tomorrow National Weather Map are show below.

North America Water Vapor (Moisture)

This map shows recent moisture content over North America. Bright and colored areas show high moisture (ie, clouds); brown indicates very little moisture present; black indicates no moisture.

Weather Topic: What are Contrails?

Home - Education - Cloud Types - Contrails

Next Topic: Cumulonimbus Clouds

A contrail is an artificial cloud, created by the passing of an aircraft.

Contrails form because water vapor in the exhaust of aircraft engines is suspended in the air under certain temperatures and humidity conditions. These contrails are called exhaust contrails.

Another type of contrail can form due to a temporary reduction in air pressure moving over the plane's surface, causing condensation. These are called aerodynamic contrails.

When you can see your breath on a cold day, it is also because of condensation. The reason contrails last longer than the condensation from your breath is because the water in contrails freezes into ice particles.

Next Topic: Cumulonimbus Clouds

Weather Topic: What are Cumulus Clouds?

Home - Education - Cloud Types - Cumulus Clouds

Next Topic: Drizzle

Cumulus clouds are fluffy and textured with rounded tops, and may have flat bottoms. The border of a cumulus cloud is clearly defined, and can have the appearance of cotton or cauliflower.

Cumulus clouds form at low altitudes (rarely above 2 km) but can grow very tall, becoming cumulus congestus and possibly the even taller cumulonimbus clouds. When cumulus clouds become taller, they have a greater chance of producing precipitation.

Next Topic: Drizzle