Forecast Details for San Antonio, TX

Recent Locations: Santa Monica, CA Bethesda, MD San Antonio, TX

Today: A 30 percent chance of showers and thunderstorms after 1pm. Mostly sunny and hot, with a high near 101. Heat index values as high as 106. South southwest wind around 5 mph becoming east in the afternoon.

Tonight: A 20 percent chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 78. East northeast wind around 5 mph.

Sunday: Sunny and hot, with a high near 101. Heat index values as high as 107. Calm wind becoming southeast around 5 mph in the afternoon.

Sunday Night: Mostly clear, with a low around 79. South southeast wind 5 to 10 mph.

Monday: A slight chance of showers between 1pm and 4pm, then a slight chance of showers and thunderstorms after 4pm. Mostly sunny and hot, with a high near 100. South southeast wind 5 to 10 mph. Chance of precipitation is 20%.

Monday Night: A slight chance of thunderstorms before 7pm. Partly cloudy, with a low around 78. East southeast wind 5 to 10 mph. Chance of precipitation is 10%.

Tuesday: Sunny, with a high near 98. South southeast wind 5 to 10 mph.

Tuesday Night: Mostly clear, with a low around 76. South southeast wind 5 to 10 mph.

Wednesday: Sunny, with a high near 98. South southeast wind 5 to 10 mph.

Wednesday Night: Mostly clear, with a low around 77.

Thursday: Sunny and hot, with a high near 99.

Thursday Night: Mostly clear, with a low around 77.

Friday: Sunny and hot, with a high near 99.

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)

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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