Hazardous Weather Conditions
Current conditions at
Marion - Williamson County Regional Airport (KMWA)
Lat: 37.77°NLon: 89.01°WElev: 486ft.
Fair
52°F
11°C
| Humidity | 50% |
| Wind Speed | NE 3 mph |
| Barometer | 30.46 in |
| Dewpoint | 34°F (1°C) |
| Visibility | 10.00 mi |
| Last update | 17 Oct 6:45 pm CDT |
Extended Forecast for
Johnston City IL
Frost Advisory October 18, 01:00am until October 18, 08:00am
Tonight
Low: 34 °F
Clear then
Areas FrostSunday
High: 69 °F
Frost then
SunnySunday Night
Low: 38 °F
Clear
Monday
High: 73 °F
Sunny
Monday Night
Low: 41 °F
Mostly Clear
Tuesday
High: 76 °F
Sunny
Tuesday Night
Low: 43 °F
Mostly Clear
Wednesday
High: 77 °F
Sunny
Wednesday Night
Low: 46 °F
Clear
Detailed Forecast
Tonight
Areas of frost after 5am. Otherwise, clear, with a low around 34. Calm wind.
Sunday
Widespread frost, mainly between 7am and 8am. Otherwise, sunny, with a high near 69. Calm wind becoming southeast around 5 mph in the afternoon.
Sunday Night
Clear, with a low around 38. Calm wind.
Monday
Sunny, with a high near 73. Calm wind.
Monday Night
Mostly clear, with a low around 41. Calm wind.
Tuesday
Sunny, with a high near 76. Light east northeast wind.
Tuesday Night
Mostly clear, with a low around 43. Calm wind.
Wednesday
Sunny, with a high near 77. Calm wind.
Wednesday Night
Clear, with a low around 46. Calm wind.
Thursday
Sunny, with a high near 78. Light north wind.
Thursday Night
Clear, with a low around 48. Calm wind.
Friday
Sunny, with a high near 78. Calm wind becoming east around 6 mph in the afternoon.
Friday Night
Mostly clear, with a low around 48. Calm wind.
Saturday
Sunny, with a high near 79. Calm wind becoming southeast around 6 mph in the afternoon.
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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
4:06 pm CDT Oct 17, 2026
7pm CDT Oct 17, 2026-6pm CDT Oct 24, 2026
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