Heavy to Excessive Rainfall and Flooding Threats in the Central and Eastern U.S.; Heat and Fire Weather Concerns in the West

Thunderstorms producing excessive rainfall and potential flooding concerns will continue through tonight from the Southern Plains to the East Coast. Areas of greatest concern for flooding are over central Texas and the Mid-Atlantic. Heat will continue to build across the West through Tuesday. Heat Advisories and Extreme Heat Warnings are in effect. Fire Weather concerns continue through Monday. Read More >

Hazardous Weather Conditions

Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Fair

80°F

27°C

Humidity 79%
Wind Speed NW 6 mph
Barometer 30.03 in (1016.1 mb)
Dewpoint 73°F (23°C)
Visibility 10.00 mi
Heat Index84°F (29°C)
Last update 13 Jul 2:56 pm CDT
Extended Forecast for

3 Miles NNW San Marcos Municipal Airport TX

Flood Watch July 13, 03:30pm until July 13, 07:00pm
Click here for hazard details and duration
Flood Watch
  •  
    Flood Watch July 13, 03:30pm until July 13, 07:00pm

    NOW until 7:00pm Sun

    Flood Watch

  • This Afternoon

    High: 89 °F

    T-storms
    Likely

  • Tonight

    Tonight: Showers and thunderstorms likely, mainly before 10pm.  Mostly cloudy, with a low around 73. Southeast wind around 5 mph.  Chance of precipitation is 60%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    Low: 73 °F

    T-storms
    Likely then
    Slight Chance
    T-storms

  • Monday

    Monday: A 40 percent chance of showers and thunderstorms after 1pm.  Partly sunny, with a high near 92. Heat index values as high as 102. South wind around 5 mph.

    High: 92 °F

    Mostly Cloudy
    then Chance
    T-storms

  • Monday Night

    Monday Night: Mostly cloudy, with a low around 74. South southeast wind around 5 mph.

    Low: 74 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: A slight chance of showers between 1pm and 4pm, then a slight chance of showers and thunderstorms after 4pm.  Partly sunny, with a high near 93. South wind 5 to 10 mph, with gusts as high as 20 mph.  Chance of precipitation is 20%.

    High: 93 °F

    Mostly Cloudy
    then Slight
    Chance
    T-storms

  • Tuesday Night

    Tuesday Night: Mostly cloudy, with a low around 74. South wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 74 °F

    Mostly Cloudy

  • Wednesday

    Wednesday: Mostly sunny, with a high near 94. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 94 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 72. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 72 °F

    Partly Cloudy

Detailed Forecast

This Afternoon
Showers and thunderstorms likely. Mostly cloudy, with a high near 89. West wind around 5 mph becoming south southeast. Chance of precipitation is 70%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Tonight
Showers and thunderstorms likely, mainly before 10pm. Mostly cloudy, with a low around 73. Southeast wind around 5 mph. Chance of precipitation is 60%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Monday
A 40 percent chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 92. Heat index values as high as 102. South wind around 5 mph.
Monday Night
Mostly cloudy, with a low around 74. South southeast wind around 5 mph.
Tuesday
A slight chance of showers between 1pm and 4pm, then a slight chance of showers and thunderstorms after 4pm. Partly sunny, with a high near 93. South wind 5 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 20%.
Tuesday Night
Mostly cloudy, with a low around 74. South wind 5 to 10 mph, with gusts as high as 20 mph.
Wednesday
Mostly sunny, with a high near 94. South wind 5 to 10 mph, with gusts as high as 20 mph.
Wednesday Night
Partly cloudy, with a low around 72. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Thursday
Mostly sunny, with a high near 94. South wind 5 to 10 mph.
Thursday Night
Partly cloudy, with a low around 72.
Friday
Mostly sunny, with a high near 93.
Friday Night
Partly cloudy, with a low around 74.
Saturday
Mostly sunny, with a high near 94.
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ABOUT THIS FORECAST

 
Point Forecast:
3 Miles NNW San Marcos Municipal Airport TX
 29.95°N 97.89°W (Elev. 646 ft)
1:50 pm CDT Jul 13, 2025
3pm CDT Jul 13, 2025-6pm CDT Jul 19, 2025
 
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Additional Resources

Radar & Satellite Image

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Hourly Weather Forecast

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