Hazardous Weather Conditions
Current conditions at
Marion - Williamson County Regional Airport (KMWA)
Lat: 37.77°NLon: 89.01°WElev: 486ft.
Partly Cloudy
72°F
22°C
| Humidity | 98% |
| Wind Speed | Calm |
| Barometer | 29.92 in |
| Dewpoint | 72°F (22°C) |
| Visibility | 10.00 mi |
| Last update | 20 Aug 2:15 am CDT |
Extended Forecast for
Herrin IL
Flood Watch until August 20, 07:00am
NOW until 7:00am Thu
Flood Watch
Overnight
Low: 71 °F
Chance
T-stormsThursday
High: 85 °F
Partly Sunny
Thursday Night
Low: 66 °F
Mostly Clear
Friday
High: 87 °F
Sunny
Friday Night
Low: 67 °F
Mostly Clear
Saturday
High: 87 °F
Mostly Sunny
then Slight
Chance
T-stormsSaturday Night
Low: 64 °F
Mostly Clear
Sunday
High: 84 °F
Sunny
Detailed Forecast
Overnight
A 50 percent chance of showers and thunderstorms, mainly before 5am. Mostly cloudy, with a steady temperature around 71. Calm wind.
Thursday
Partly sunny, with a high near 85. Calm wind becoming north around 6 mph in the afternoon.
Thursday Night
Mostly clear, with a low around 66. Calm wind.
Friday
Sunny, with a high near 87. Light north wind.
Friday Night
Mostly clear, with a low around 67. Calm wind.
Saturday
A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 87. Calm wind becoming northwest 5 to 8 mph in the morning.
Saturday Night
Mostly clear, with a low around 64. Light north wind.
Sunday
Sunny, with a high near 84. Calm wind becoming north northwest 5 to 7 mph in the afternoon.
Sunday Night
Partly cloudy, with a low around 62. Light and variable wind.
Monday
A slight chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 84. Calm wind becoming east southeast around 6 mph in the afternoon.
Monday Night
A slight chance of showers and thunderstorms. Partly cloudy, with a low around 63. Light east southeast wind.
Tuesday
A slight chance of showers. Mostly sunny, with a high near 87. South southeast wind 3 to 6 mph.
Tuesday Night
Partly cloudy, with a low around 66. Light southeast wind.
Wednesday
A slight chance of showers and thunderstorms. Mostly sunny, with a high near 89. Calm wind becoming northwest around 6 mph in the afternoon.
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Forecast AreaABOUT THIS FORECAST
Point Forecast:
Herrin IL
37.81°N 89.06°W
37.81°N 89.06°W
1:51 am CDT Aug 20, 2026
2am CDT Aug 20, 2026-6pm CDT Aug 26, 2026
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