National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce

Lake Effect Snow through Friday; Heavy Rain, Thunderstorms and Mountain Snow in California

Periods of moderate to heavy lake effect snow will continue through Friday downwind of Lake Erie and Ontario. Several additional inches of accumulating snow are expected. A Pacific storm will bring heavy rain and mountain snow across California, the Southwest and Intermountain West today. Isolated severe thunderstorms and scattered flash flooding is possible across parts of southern California. Read More >

Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Fair

70°F

21°C

Humidity 26%
Wind Speed SW 18 mph
Barometer 30.11 in (1019.2 mb)
Dewpoint 33°F (1°C)
Visibility 10.00 mi
Last update 1 Jan 11:56 am CST
Extended Forecast for

San Marcos Municipal Airport TX

  • New Year's Day

    New Year's Day: Partly sunny, with a high near 73. South southwest wind 10 to 15 mph, with gusts as high as 20 mph.

    High: 73 °F

    Partly Sunny

  • Tonight

    Tonight: Mostly cloudy, then gradually becoming mostly clear, with a low around 52. South southwest wind 5 to 10 mph.

    Low: 52 °F

    Decreasing
    Clouds

  • Friday

    Friday: Sunny, with a high near 86. South southwest wind 5 to 15 mph becoming west in the afternoon. Winds could gust as high as 25 mph.

    High: 86 °F

    Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 54. West wind 5 to 10 mph.

    Low: 54 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 76. Northwest wind 10 to 15 mph becoming north northeast in the afternoon. Winds could gust as high as 20 mph.

    High: 76 °F

    Sunny

  • Saturday Night

    Saturday Night: Clear, with a low around 42. North wind around 5 mph.

    Low: 42 °F

    Clear

  • Sunday

    Sunday: Sunny, with a high near 72. Calm wind becoming east southeast around 5 mph in the afternoon.

    High: 72 °F

    Sunny

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 49. South wind around 5 mph.

    Low: 49 °F

    Partly Cloudy

  • Monday

    Monday: Mostly cloudy, with a high near 76. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 76 °F

    Mostly Cloudy

Detailed Forecast

New Year's Day
Partly sunny, with a high near 73. South southwest wind 10 to 15 mph, with gusts as high as 20 mph.
Tonight
Mostly cloudy, then gradually becoming mostly clear, with a low around 52. South southwest wind 5 to 10 mph.
Friday
Sunny, with a high near 86. South southwest wind 5 to 15 mph becoming west in the afternoon. Winds could gust as high as 25 mph.
Friday Night
Mostly clear, with a low around 54. West wind 5 to 10 mph.
Saturday
Sunny, with a high near 76. Northwest wind 10 to 15 mph becoming north northeast in the afternoon. Winds could gust as high as 20 mph.
Saturday Night
Clear, with a low around 42. North wind around 5 mph.
Sunday
Sunny, with a high near 72. Calm wind becoming east southeast around 5 mph in the afternoon.
Sunday Night
Partly cloudy, with a low around 49. South wind around 5 mph.
Monday
Mostly cloudy, with a high near 76. South wind 5 to 10 mph, with gusts as high as 20 mph.
Monday Night
Mostly cloudy, with a low around 58.
Tuesday
Partly sunny, with a high near 80.
Tuesday Night
Mostly clear, with a low around 57.
Wednesday
Partly sunny, with a high near 78.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
San Marcos Municipal Airport TX
 29.88°N 97.86°W (Elev. 600 ft)
Last Update:
12:30 pm CST Jan 1, 2026
Forecast Valid:
12pm CST Jan 1, 2026-6pm CST Jan 7, 2026
 
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