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

Atmospheric River Bringing Heavy Rain to Southern California and Heavy Snow to the Sierra Nevadas

A strong atmospheric river will continue heavy rain over southern California through Friday. The heaviest rainfall is ongoing today in the Los Angeles Basin. Flash and urban flooding is possible. A prolonged heavy snowfall has begun over the Sierra Nevada Mountains and will continue through Friday. Travel will become increasingly difficult over the passes due to snow and strong winds. Read More >

Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Overcast

67°F

19°C

Humidity 100%
Wind Speed SW 3 mph
Barometer 30.32 in (1026.1 mb)
Dewpoint 67°F (19°C)
Visibility 10.00 mi
Last update 24 Dec 8:56 am CST
Extended Forecast for

San Marcos TX

  • Today

    Today: Mostly cloudy, then gradually becoming sunny, with a high near 79. South wind around 5 mph.

    High: 79 °F

    Decreasing
    Clouds

  • Tonight

    Tonight: Increasing clouds, with a low around 63. South southwest wind around 5 mph.

    Low: 63 °F

    Increasing
    Clouds

  • Christmas Day

    Christmas Day: Cloudy through mid morning, then gradual clearing, with a high near 78. South southwest wind 5 to 10 mph.

    High: 78 °F

    Gradual
    Clearing

  • Thursday Night

    Thursday Night: Increasing clouds, with a low around 62. South wind around 5 mph.

    Low: 62 °F

    Increasing
    Clouds

  • Friday

    Friday: Partly sunny, with a high near 80. South southwest wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 80 °F

    Partly Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 64. South wind around 5 mph.

    Low: 64 °F

    Partly Cloudy

  • Saturday

    Saturday: Partly sunny, with a high near 81. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 81 °F

    Partly Sunny

  • Saturday Night

    Saturday Night: Mostly cloudy, with a low around 64. South wind 5 to 10 mph.

    Low: 64 °F

    Mostly Cloudy

  • Sunday

    Sunday: Mostly cloudy, with a high near 76. South wind 5 to 10 mph becoming north in the afternoon. Winds could gust as high as 20 mph.

    High: 76 °F

    Mostly Cloudy

Detailed Forecast

Today
Mostly cloudy, then gradually becoming sunny, with a high near 79. South wind around 5 mph.
Tonight
Increasing clouds, with a low around 63. South southwest wind around 5 mph.
Christmas Day
Cloudy through mid morning, then gradual clearing, with a high near 78. South southwest wind 5 to 10 mph.
Thursday Night
Increasing clouds, with a low around 62. South wind around 5 mph.
Friday
Partly sunny, with a high near 80. South southwest wind 5 to 10 mph, with gusts as high as 20 mph.
Friday Night
Partly cloudy, with a low around 64. South wind around 5 mph.
Saturday
Partly sunny, with a high near 81. South wind 5 to 10 mph, with gusts as high as 20 mph.
Saturday Night
Mostly cloudy, with a low around 64. South wind 5 to 10 mph.
Sunday
Mostly cloudy, with a high near 76. South wind 5 to 10 mph becoming north in the afternoon. Winds could gust as high as 20 mph.
Sunday Night
A 20 percent chance of showers before midnight. Mostly cloudy, with a low around 43.
Monday
Mostly cloudy, with a high near 50.
Monday Night
Mostly cloudy, with a low around 34.
Tuesday
Mostly sunny, with a high near 56.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
San Marcos TX
 29.88°N 97.94°W (Elev. 577 ft)
Last Update:
8:44 am CST Dec 24, 2025
Forecast Valid:
9am CST Dec 24, 2025-6pm CST Dec 30, 2025
 
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