Thunderstorms and Heavy Rain in the Mid-South; Heat Continues in the Southeast and Southwest

Severe thunderstorms and heavy rain are expected across portions of the mid-Mississippi Valley into the Ohio Valley and portions of Arizona. Dangerous heat persists in the South and Southeast while building into the Southwest. Overnight lows will be so warm that, when combined with oppressive dew points, little-to-no relief from the scorching daytime highs will be available. Read More >

Current conditions at

Knoxville, McGhee Tyson Airport (KTYS)

Lat: 35.82°NLon: 83.99°WElev: 981ft.

Partly Cloudy

81°F

27°C

Humidity 62%
Wind Speed NW 7 mph
Barometer 29.97 in (1013.6 mb)
Dewpoint 67°F (19°C)
Visibility 10.00 mi
Heat Index83°F (28°C)
Last update 18 Aug 8:53 pm EDT
Extended Forecast for

Maryville TN

  • Tonight

    Tonight: Patchy fog after 4am.  Otherwise, mostly clear, with a low around 67. North wind around 5 mph becoming calm.

    Low: 67 °F

    Mostly Clear
    then Patchy
    Fog

  • Wednesday

    Wednesday: Patchy fog before 8am.  Otherwise, sunny and hot, with a high near 91. Calm wind becoming north around 5 mph.

    High: 91 °F

    Patchy Fog
    then Sunny

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 70. Calm wind.

    Low: 70 °F

    Partly Cloudy

  • Thursday

    Thursday: A slight chance of showers, with thunderstorms also possible after 11am.  Partly sunny and hot, with a high near 91. Heat index values as high as 98. Calm wind becoming west around 5 mph in the afternoon.  Chance of precipitation is 20%.

    High: 91 °F

    Slight Chance
    T-storms

  • Thursday Night

    Thursday Night: A chance of showers and thunderstorms.  Partly cloudy, with a low around 70. Northwest wind around 5 mph becoming calm.  Chance of precipitation is 40%.

    Low: 70 °F

    Chance
    Showers

  • Friday

    Friday: A chance of showers before 11am, then a chance of showers and thunderstorms between 11am and 2pm, then showers likely and possibly a thunderstorm after 2pm.  Mostly sunny, with a high near 89. Calm wind becoming west around 5 mph in the afternoon.  Chance of precipitation is 60%.

    High: 89 °F

    Chance
    Showers then
    Showers
    Likely

  • Friday Night

    Friday Night: Showers likely and possibly a thunderstorm before 8pm, then a chance of showers and thunderstorms between 8pm and 2am.  Mostly cloudy, with a low around 68. West wind around 5 mph becoming calm.  Chance of precipitation is 60%.

    Low: 68 °F

    Showers
    Likely then
    Chance
    T-storms

  • Saturday

    Saturday: Mostly sunny, with a high near 89.

    High: 89 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 67.

    Low: 67 °F

    Mostly Clear

Detailed Forecast

Tonight
Patchy fog after 4am. Otherwise, mostly clear, with a low around 67. North wind around 5 mph becoming calm.
Wednesday
Patchy fog before 8am. Otherwise, sunny and hot, with a high near 91. Calm wind becoming north around 5 mph.
Wednesday Night
Partly cloudy, with a low around 70. Calm wind.
Thursday
A slight chance of showers, with thunderstorms also possible after 11am. Partly sunny and hot, with a high near 91. Heat index values as high as 98. Calm wind becoming west around 5 mph in the afternoon. Chance of precipitation is 20%.
Thursday Night
A chance of showers and thunderstorms. Partly cloudy, with a low around 70. Northwest wind around 5 mph becoming calm. Chance of precipitation is 40%.
Friday
A chance of showers before 11am, then a chance of showers and thunderstorms between 11am and 2pm, then showers likely and possibly a thunderstorm after 2pm. Mostly sunny, with a high near 89. Calm wind becoming west around 5 mph in the afternoon. Chance of precipitation is 60%.
Friday Night
Showers likely and possibly a thunderstorm before 8pm, then a chance of showers and thunderstorms between 8pm and 2am. Mostly cloudy, with a low around 68. West wind around 5 mph becoming calm. Chance of precipitation is 60%.
Saturday
Mostly sunny, with a high near 89.
Saturday Night
Mostly clear, with a low around 67.
Sunday
Sunny, with a high near 88.
Sunday Night
Partly cloudy, with a low around 65.
Monday
Mostly sunny, with a high near 88.
Monday Night
Partly cloudy, with a low around 66.
Tuesday
A 20 percent chance of showers and thunderstorms. Mostly sunny and hot, with a high near 91.
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ABOUT THIS FORECAST

 
Point Forecast:
Maryville TN
 35.74°N 83.96°W (Elev. 1010 ft)
7:06 pm EDT Aug 18, 2026
9pm EDT Aug 18, 2026-6pm EDT Aug 25, 2026
 
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Additional Resources

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