Hazardous Weather Conditions
Current conditions at
Marion - Williamson County Regional Airport (KMWA)
Lat: 37.77°NLon: 89.01°WElev: 486ft.
Fair
80°F
27°C
| Humidity | 75% |
| Wind Speed | SW 6 mph |
| Barometer | 30.07 in |
| Dewpoint | 72°F (22°C) |
| Visibility | 10.00 mi |
| Heat Index | 84°F (29°C) |
| Last update | 16 Aug 12:35 am CDT |
Extended Forecast for
Johnston City IL
Extreme Heat Warning August 16, 12:53am until August 16, 08:00pm
NOW until 8:00pm Sun
Extreme Heat Warning
Overnight
Low: 79 °F
Mostly Clear
Sunday
High: 99 °F
Mostly Sunny
then Slight
Chance
T-stormsSunday Night
Low: 74 °F
Chance
T-storms then
Chance
ShowersMonday
High: 89 °F
Decreasing
CloudsMonday Night
Low: 67 °F
Mostly Clear
Tuesday
High: 92 °F
Sunny
Tuesday Night
Low: 71 °F
Mostly Clear
then Slight
Chance
T-stormsWednesday
High: 93 °F
Chance
Showers
Detailed Forecast
Overnight
Mostly clear, with a steady temperature around 79. South southwest wind 3 to 7 mph.
Sunday
A 10 percent chance of showers and thunderstorms after 5pm. Mostly sunny and hot, with a high near 99. Heat index values as high as 110. West wind 6 to 9 mph.
Sunday Night
A 30 percent chance of showers and thunderstorms, mainly after 1am. Mostly cloudy, with a low around 74. Light and variable wind.
Monday
Mostly cloudy, then gradually becoming sunny, with a high near 89. North northwest wind 3 to 8 mph.
Monday Night
Mostly clear, with a low around 67. North wind around 6 mph becoming calm in the evening.
Tuesday
Sunny, with a high near 92. Calm wind.
Tuesday Night
A 20 percent chance of showers and thunderstorms after 1am. Mostly clear, with a low around 71. Calm wind.
Wednesday
A chance of showers and thunderstorms, mainly before 1pm. Mostly sunny, with a high near 93. Calm wind becoming west southwest 5 to 8 mph in the morning.
Wednesday Night
Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 69. North northeast wind 3 to 7 mph.
Thursday
A chance of showers and thunderstorms, mainly before 1pm. Partly sunny, with a high near 86. Northeast wind 3 to 8 mph.
Thursday Night
A chance of showers and thunderstorms. Partly cloudy, with a low around 66. Northeast wind around 6 mph becoming calm in the evening.
Friday
A slight chance of showers and thunderstorms. Mostly sunny, with a high near 86. North northeast wind 3 to 7 mph.
Friday Night
Partly cloudy, with a low around 64. Light north northeast wind.
Saturday
Mostly sunny, with a high near 88. Calm wind becoming north northwest 5 to 8 mph in the morning.
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Forecast AreaABOUT THIS FORECAST
Point Forecast:
Johnston City IL
37.82°N 88.91°W
37.82°N 88.91°W
12:26 am CDT Aug 16, 2026
12am CDT Aug 16, 2026-6pm CDT Aug 22, 2026
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