Severe Thunderstorms in the Midwest and Arizona; Heat Continues in the Southeast and Southwest

Thunderstorms, some severe, may lead to scattered instances of flash flooding across the Midwest and Ohio Valley and southern Arizona. The threat will shift to the Mid-Atlantic coast on Thursday. Dangerous heat persists in the South and Southeast while building into the Southwest. Overnight lows will be so warm that little-to-no relief from the scorching daytime highs will be available. Read More >

Hazardous Weather Conditions

Current conditions at

Knoxville, McGhee Tyson Airport (KTYS)

Lat: 35.82°NLon: 83.99°WElev: 981ft.

Light Rain

72°F

22°C

Humidity 91%
Wind Speed SE 6 mph
Barometer 30.00 in (1014.7 mb)
Dewpoint 69°F (21°C)
Visibility 10.00 mi
Last update 20 Aug 6:53 am EDT
Extended Forecast for

Knoxville TN

  • Today

    Today: A chance of showers and thunderstorms before 4pm, then a slight chance of showers and thunderstorms after 5pm.  Partly sunny and hot, with a high near 91. Heat index values as high as 98. West wind around 5 mph.  Chance of precipitation is 30%.

    High: 91 °F

    Chance
    Showers then
    Slight Chance
    T-storms

  • Tonight

    Tonight: A chance of showers and thunderstorms before midnight, then showers likely and possibly a thunderstorm between midnight and 2am, then a chance of showers and thunderstorms after 2am.  Mostly cloudy, with a low around 70. Northwest wind around 5 mph becoming calm.  Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    Low: 70 °F

    Chance
    T-storms then
    Showers
    Likely

  • Friday

    Friday: A chance of showers and thunderstorms before 8am, then a slight chance of showers and thunderstorms after 3pm.  Partly sunny, with a high near 88. Calm wind becoming west around 5 mph.  Chance of precipitation is 30%.

    High: 88 °F

    Chance
    Showers then
    Slight Chance
    T-storms

  • Friday Night

    Friday Night: A 30 percent chance of showers and thunderstorms before 8pm.  Partly cloudy, with a low around 69. Calm wind.

    Low: 69 °F

    Chance
    T-storms then
    Partly Cloudy

  • Saturday

    Saturday: Mostly sunny and hot, with a high near 90. Calm wind becoming west around 5 mph.

    High: 90 °F

    Hot

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 67. West wind around 5 mph becoming calm.

    Low: 67 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 88. Calm wind becoming northwest around 5 mph in the afternoon.

    High: 88 °F

    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 63.

    Low: 63 °F

    Mostly Clear

  • Monday

    Monday: Sunny, with a high near 87.

    High: 87 °F

    Sunny

Detailed Forecast

Today
A chance of showers and thunderstorms before 4pm, then a slight chance of showers and thunderstorms after 5pm. Partly sunny and hot, with a high near 91. Heat index values as high as 98. West wind around 5 mph. Chance of precipitation is 30%.
Tonight
A chance of showers and thunderstorms before midnight, then showers likely and possibly a thunderstorm between midnight and 2am, then a chance of showers and thunderstorms after 2am. Mostly cloudy, with a low around 70. Northwest wind around 5 mph becoming calm. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Friday
A chance of showers and thunderstorms before 8am, then a slight chance of showers and thunderstorms after 3pm. Partly sunny, with a high near 88. Calm wind becoming west around 5 mph. Chance of precipitation is 30%.
Friday Night
A 30 percent chance of showers and thunderstorms before 8pm. Partly cloudy, with a low around 69. Calm wind.
Saturday
Mostly sunny and hot, with a high near 90. Calm wind becoming west around 5 mph.
Saturday Night
Mostly clear, with a low around 67. West wind around 5 mph becoming calm.
Sunday
Sunny, with a high near 88. Calm wind becoming northwest around 5 mph in the afternoon.
Sunday Night
Mostly clear, with a low around 63.
Monday
Sunny, with a high near 87.
Monday Night
Partly cloudy, with a low around 64.
Tuesday
Mostly sunny, with a high near 89.
Tuesday Night
Partly cloudy, with a low around 67.
Wednesday
A 30 percent chance of showers and thunderstorms. Mostly sunny and hot, with a high near 91.
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ABOUT THIS FORECAST

 
Point Forecast:
Knoxville TN
 35.98°N 83.97°W (Elev. 1096 ft)
7:06 am EDT Aug 20, 2026
7am EDT Aug 20, 2026-6pm EDT Aug 26, 2026
 
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Additional Resources

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