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

Dangerous Heat over the South-Central and Southwest U.S. Through Next Week

Dangerous heat persists across the Desert Southwest through this weekend and across the Southern Plains and Lower Mississippi Valley through at least the middle of next week. Numerous daily record high temperatures are expected through at least Tuesday for much of Texas and Oklahoma as well as portions of Louisiana, New Mexico, and Arizona. Read More >

Current conditions at

St. Louis Regional Airport (KALN)

Lat: 38.89°NLon: 90.03°WElev: 518ft.

Fair

81°F

27°C

Humidity 62%
Wind Speed S 7 mph
Barometer 30.10 in
Dewpoint 66°F (19°C)
Visibility 10.00 mi
Heat Index83°F (28°C)
Last update 21 Aug 11:50 am CDT
Extended Forecast for

Maryville IL

  • Today

    Today: Sunny, with a high near 86. Light west wind.

    High: 86 °F

    Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 70. Light and variable wind.

    Low: 70 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 86. North wind 6 to 10 mph.

    High: 86 °F

    Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 64. North wind 5 to 7 mph becoming calm in the evening.

    Low: 64 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 83. Calm wind becoming north 5 to 7 mph in the afternoon.

    High: 83 °F

    Sunny

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 62.

    Low: 62 °F

    Partly Cloudy

  • Monday

    Monday: Partly sunny, with a high near 82.

    High: 82 °F

    Partly Sunny

  • Monday Night

    Monday Night: A 30 percent chance of showers and thunderstorms, mainly before 1am. Partly cloudy, with a low around 65.

    Low: 65 °F

    Chance
    T-storms

  • Tuesday

    Tuesday: Mostly sunny, with a high near 85.

    High: 85 °F

    Mostly Sunny

Detailed Forecast

Today
Sunny, with a high near 86. Light west wind.
Tonight
Mostly clear, with a low around 70. Light and variable wind.
Saturday
Sunny, with a high near 86. North wind 6 to 10 mph.
Saturday Night
Mostly clear, with a low around 64. North wind 5 to 7 mph becoming calm in the evening.
Sunday
Sunny, with a high near 83. Calm wind becoming north 5 to 7 mph in the afternoon.
Sunday Night
Partly cloudy, with a low around 62.
Monday
Partly sunny, with a high near 82.
Monday Night
A 30 percent chance of showers and thunderstorms, mainly before 1am. Partly cloudy, with a low around 65.
Tuesday
Mostly sunny, with a high near 85.
Tuesday Night
A 20 percent chance of showers and thunderstorms after 1am. Partly cloudy, with a low around 68.
Wednesday
Partly sunny, with a high near 86.
Wednesday Night
A 20 percent chance of showers and thunderstorms. Partly cloudy, with a low around 66.
Thursday
Sunny, with a high near 86.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Maryville IL
 38.72°N 89.97°W (Elev. 558 ft)
Last Update:
11:51 am CDT Aug 21, 2026
Forecast Valid:
11am CDT Aug 21, 2026-6pm CDT Aug 27, 2026
 
Forecast Discussion
 
Get as KML Get as XML

Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation