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Severe Thunderstorms With Heavy Rain Possible In The Upper Midwest; Excessive Heat For Central U.S.

Several rounds of strong to severe thunderstorms will be possible from the northern Plains and upper Midwest to the Great Lakes through Friday. Damaging winds, large hail, and flooding will be the primary threats with these storms. Excessive heat will grip the central Plains with heat indices approaching 105 to 110 degrees. Very hot and humid conditions are likely to expand into the Mid Atlantic. Read More >

Hazardous Weather Conditions

Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Fair

77°F

25°C

Humidity 79%
Wind Speed S 6 mph
Barometer 30.04 in
Dewpoint 70°F (21°C)
Visibility 10.00 mi
Heat Index79°F (26°C)
Last update 21 Jul 3:35 am CDT
Extended Forecast for

San Marcos TX

  • Overnight

    Overnight: Partly cloudy, with a low around 74. South southwest wind around 5 mph.

    Partly Cloudy

    Low: 74 °F

  • Friday

    Friday: Mostly sunny and hot, with a high near 100. Heat index values as high as 104. South southwest wind 5 to 10 mph.

    Hot

    High: 100 °F

  • Friday
    Night

    Friday Night: Partly cloudy, with a low around 76. South southeast wind 5 to 15 mph.

    Partly Cloudy

    Low: 76 °F

  • Saturday

    Saturday: Mostly sunny and hot, with a high near 100. Heat index values as high as 106. South wind 5 to 10 mph.

    Hot

    High: 100 °F

  • Saturday
    Night

    Saturday Night: A 20 percent chance of showers before 10pm.  Partly cloudy, with a low around 76. South southeast wind 10 to 15 mph.

    Slight Chance
    Showers then
    Partly Cloudy

    Low: 76 °F

  • Sunday

    Sunday: A 20 percent chance of showers and thunderstorms.  Mostly sunny and hot, with a high near 99. South wind 10 to 15 mph.

    Slight Chance
    T-storms

    High: 99 °F

  • Sunday
    Night

    Sunday Night: Partly cloudy, with a low around 76. South southeast wind 10 to 15 mph.

    Partly Cloudy

    Low: 76 °F

  • Monday

    Monday: Mostly sunny and hot, with a high near 100. South wind 10 to 15 mph.

    Hot

    High: 100 °F

  • Monday
    Night

    Monday Night: Partly cloudy, with a low around 75. South wind 10 to 15 mph, with gusts as high as 20 mph.

    Partly Cloudy

    Low: 75 °F

Detailed Forecast

Overnight
Partly cloudy, with a low around 74. South southwest wind around 5 mph.
Friday
Mostly sunny and hot, with a high near 100. Heat index values as high as 104. South southwest wind 5 to 10 mph.
Friday Night
Partly cloudy, with a low around 76. South southeast wind 5 to 15 mph.
Saturday
Mostly sunny and hot, with a high near 100. Heat index values as high as 106. South wind 5 to 10 mph.
Saturday Night
A 20 percent chance of showers before 10pm. Partly cloudy, with a low around 76. South southeast wind 10 to 15 mph.
Sunday
A 20 percent chance of showers and thunderstorms. Mostly sunny and hot, with a high near 99. South wind 10 to 15 mph.
Sunday Night
Partly cloudy, with a low around 76. South southeast wind 10 to 15 mph.
Monday
Mostly sunny and hot, with a high near 100. South wind 10 to 15 mph.
Monday Night
Partly cloudy, with a low around 75. South wind 10 to 15 mph, with gusts as high as 20 mph.
Tuesday
A 20 percent chance of showers and thunderstorms. Mostly sunny and hot, with a high near 99.
Tuesday Night
Partly cloudy, with a low around 75.
Wednesday
A 20 percent chance of showers and thunderstorms. Mostly sunny and hot, with a high near 99.
Wednesday Night
Partly cloudy, with a low around 75.
Thursday
Mostly sunny and hot, with a high near 100.
Click Map For Forecast
Point Forecast:
San Marcos TX
 29.88°N 97.94°W (Elev. 577 ft)
3:12 am CDT Jul 21, 2017
3am CDT Jul 21, 2017-6pm CDT Jul 27, 2017
 
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