Hazardous Weather Conditions
Current conditions at
Marion - Williamson County Regional Airport (KMWA)
Lat: 37.77°NLon: 89.01°WElev: 486ft.
Fair
66°F
19°C
| Humidity | 100% |
| Wind Speed | Calm |
| Barometer | 30.08 in |
| Dewpoint | 66°F (19°C) |
| Visibility | 10.00 mi |
| Last update | 18 Aug 6:45 am CDT |
Extended Forecast for
Johnston City IL
Today
High: 89 °F
Patchy Fog
then SunnyTonight
Low: 69 °F
Increasing
CloudsWednesday
High: 88 °F
Chance
T-stormsWednesday Night
Low: 68 °F
Chance
T-storms then
Showers
LikelyThursday
High: 85 °F
Chance
ShowersThursday Night
Low: 66 °F
Partly Cloudy
Friday
High: 87 °F
Sunny
Friday Night
Low: 65 °F
Mostly Clear
Saturday
High: 89 °F
Sunny
Detailed Forecast
Today
Patchy fog before 8am. Otherwise, sunny, with a high near 89. Calm wind.
Tonight
Increasing clouds, with a low around 69. Light and variable wind.
Wednesday
A 50 percent chance of showers and thunderstorms, mainly after 5pm. Cloudy, then gradually becoming mostly sunny, with a high near 88. Light and variable wind becoming east southeast around 6 mph in the morning.
Wednesday Night
A chance of showers and thunderstorms between 7pm and 1am, then showers likely and possibly a thunderstorm after 1am. Mostly cloudy, with a low around 68. Light north northeast wind. Chance of precipitation is 70%.
Thursday
A 30 percent chance of showers and thunderstorms before 1pm. Partly sunny, with a high near 85. Calm wind becoming north northeast around 6 mph in the morning.
Thursday Night
Partly cloudy, with a low around 66. North northeast wind around 5 mph becoming calm in the evening.
Friday
Sunny, with a high near 87. Calm wind becoming north 5 to 7 mph in the afternoon.
Friday Night
Mostly clear, with a low around 65. Calm wind.
Saturday
Sunny, with a high near 89. Calm wind becoming northwest 5 to 9 mph in the afternoon.
Saturday Night
Mostly clear, with a low around 65. North northwest wind around 5 mph becoming calm in the evening.
Sunday
Sunny, with a high near 87. Calm wind becoming north 5 to 7 mph in the afternoon.
Sunday Night
Partly cloudy, with a low around 65. Northeast wind around 5 mph becoming calm in the evening.
Monday
Mostly sunny, with a high near 88. Calm wind becoming southeast 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
6:06 am CDT Aug 18, 2026
7am CDT Aug 18, 2026-6pm CDT Aug 24, 2026
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