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

Strong Atmospheric River Bringing Heavy Rain to the Pacific Northwest; Areas of Snow in the North-Central and Eastern U.S.

A strong atmospheric river will bring prolonged heavy rainfall along with gusty winds to the Pacific Northwest through much of this week. The heavy rainfall may lead to widespread urban and river flooding. Accumulating snow is expected over parts of the central Appalachians and Mid-Atlantic today as well as the Upper Midwest and the Upper Great Lakes this evening into Tuesday. Read More >

Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Fair

59°F

15°C

Humidity 35%
Wind Speed NE 7 mph
Barometer 30.25 in (1024.4 mb)
Dewpoint 31°F (-1°C)
Visibility 10.00 mi
Last update 8 Dec 4:56 pm CST
Extended Forecast for

San Marcos Municipal Airport TX

  • Tonight

    Tonight: Clear, with a low around 34. East northeast wind around 5 mph becoming calm in the evening.

    Low: 34 °F

    Clear

  • Tuesday

    Tuesday: Sunny, with a high near 67. Light west southwest wind becoming south southwest 10 to 15 mph in the morning. Winds could gust as high as 20 mph.

    High: 67 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Clear, with a low around 44. South southwest wind around 10 mph.

    Low: 44 °F

    Clear

  • Wednesday

    Wednesday: Sunny, with a high near 76. Southwest wind 5 to 10 mph becoming north northeast in the afternoon.

    High: 76 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 43. North wind around 5 mph.

    Low: 43 °F

    Mostly Clear

  • Thursday

    Thursday: Sunny, with a high near 73. North wind around 5 mph becoming south in the afternoon.

    High: 73 °F

    Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 52. South southwest wind around 5 mph.

    Low: 52 °F

    Mostly Clear

  • Friday

    Friday: Partly sunny, with a high near 76. South southwest wind 5 to 10 mph becoming east northeast in the afternoon. Winds could gust as high as 20 mph.

    High: 76 °F

    Partly Sunny

  • Friday Night

    Friday Night: Mostly cloudy, with a low around 54. Northeast wind around 10 mph.

    Low: 54 °F

    Mostly Cloudy

Detailed Forecast

Tonight
Clear, with a low around 34. East northeast wind around 5 mph becoming calm in the evening.
Tuesday
Sunny, with a high near 67. Light west southwest wind becoming south southwest 10 to 15 mph in the morning. Winds could gust as high as 20 mph.
Tuesday Night
Clear, with a low around 44. South southwest wind around 10 mph.
Wednesday
Sunny, with a high near 76. Southwest wind 5 to 10 mph becoming north northeast in the afternoon.
Wednesday Night
Mostly clear, with a low around 43. North wind around 5 mph.
Thursday
Sunny, with a high near 73. North wind around 5 mph becoming south in the afternoon.
Thursday Night
Mostly clear, with a low around 52. South southwest wind around 5 mph.
Friday
Partly sunny, with a high near 76. South southwest wind 5 to 10 mph becoming east northeast in the afternoon. Winds could gust as high as 20 mph.
Friday Night
Mostly cloudy, with a low around 54. Northeast wind around 10 mph.
Saturday
Partly sunny, with a high near 69.
Saturday Night
Mostly cloudy, with a low around 53.
Sunday
Mostly cloudy, with a high near 69.
Sunday Night
Mostly cloudy, with a low around 54.
Monday
Mostly cloudy, with a high near 70.
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ABOUT THIS FORECAST

 
Point Forecast:
San Marcos Municipal Airport TX
 29.9°N 97.86°W (Elev. 600 ft)
Last Update:
5:02 pm CST Dec 8, 2025
Forecast Valid:
5pm CST Dec 8, 2025-6pm CST Dec 15, 2025
 
Forecast Discussion
 
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Additional Resources

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