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Hazardous Weather Conditions

Current conditions at

Southern Illinois Airport (KMDH)

Lat: 37.78°NLon: 89.25°WElev: 400ft.

Freezing Fog

10°F

-12°C

Humidity 87%
Wind Speed N 14 mph
Barometer 30.06 in (1018.7 mb)
Dewpoint 7°F (-14°C)
Visibility 0.50 mi
Wind Chill-6°F (-21°C)
Last update 25 Jan 3:52 am CST
Extended Forecast for

Saint Johns IL

Cold Weather Advisory January 25, 03:56am until January 26, 12:00am
Extreme Cold Warning January 26, 12:00am until January 27, 10:00am
Winter Storm Warning January 25, 03:56am until January 25, 06:00pm
Click here for hazard details and duration
Cold Weather Advisory
Extreme Cold Warning
Winter Storm Warning
  •  
    Cold Weather Advisory January 25, 03:56am until January 26, 12:00am
    Winter Storm Warning January 25, 03:56am until January 25, 06:00pm

    NOW: Multiple hazards in effect

    Click HERE for Details

  • Overnight

    Low: 11 °F

    Heavy Snow

  • Sunday

    Sunday: Snow, mainly before 3pm. The snow could be heavy at times. High near 13. Wind chill values as low as -4. North northwest wind 11 to 15 mph, with gusts as high as 28 mph. Chance of precipitation is 100%. New snow accumulation of 3 to 7 inches possible.

    High: 13 °F

    Heavy Snow
    then Snow
    Likely

  • Sunday Night

    Sunday Night: Cloudy during the early evening, then gradual clearing, with a low around -5. Wind chill values as low as -17. Northwest wind 8 to 13 mph, with gusts as high as 25 mph.

    Low: -5 °F

    Gradual
    Clearing

  • Monday

    Monday: Sunny, with a high near 14. Wind chill values as low as -19. West northwest wind 5 to 9 mph becoming light and variable in the afternoon.

    High: 14 °F

    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 1. Light southwest wind becoming south southwest 6 to 11 mph in the evening. Winds could gust as high as 20 mph.

    Low: 1 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny, with a high near 30. Southwest wind 5 to 10 mph becoming northwest in the afternoon. Winds could gust as high as 18 mph.

    High: 30 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Partly cloudy, with a low around -3. Light north northwest wind.

    Low: -3 °F

    Partly Cloudy

  • Wednesday

    Wednesday: Mostly sunny, with a high near 22. Calm wind becoming west 5 to 7 mph in the morning.

    High: 22 °F

    Mostly Sunny

Detailed Forecast

Overnight
Snow. The snow could be heavy at times. Low around 11. Wind chill values as low as -4. North wind 10 to 13 mph, with gusts as high as 23 mph. Chance of precipitation is 100%. Total nighttime snow accumulation of 3 to 5 inches possible.
Sunday
Snow, mainly before 3pm. The snow could be heavy at times. High near 13. Wind chill values as low as -4. North northwest wind 11 to 15 mph, with gusts as high as 28 mph. Chance of precipitation is 100%. New snow accumulation of 3 to 7 inches possible.
Sunday Night
Cloudy during the early evening, then gradual clearing, with a low around -5. Wind chill values as low as -17. Northwest wind 8 to 13 mph, with gusts as high as 25 mph.
Monday
Sunny, with a high near 14. Wind chill values as low as -19. West northwest wind 5 to 9 mph becoming light and variable in the afternoon.
Monday Night
Mostly clear, with a low around 1. Light southwest wind becoming south southwest 6 to 11 mph in the evening. Winds could gust as high as 20 mph.
Tuesday
Sunny, with a high near 30. Southwest wind 5 to 10 mph becoming northwest in the afternoon. Winds could gust as high as 18 mph.
Tuesday Night
Partly cloudy, with a low around -3. Light north northwest wind.
Wednesday
Mostly sunny, with a high near 22. Calm wind becoming west 5 to 7 mph in the morning.
Wednesday Night
Partly cloudy, with a low around 0. North northwest wind 3 to 5 mph.
Thursday
Partly sunny, with a high near 20. North northwest wind around 6 mph.
Thursday Night
Mostly cloudy, with a low around 6. North northeast wind 3 to 5 mph.
Friday
Partly sunny, with a high near 22. North wind 5 to 7 mph.
Friday Night
Partly cloudy, with a low around 2. North northwest wind 3 to 5 mph.
Saturday
Mostly sunny, with a high near 20. Northwest wind 5 to 7 mph.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Saint Johns IL
 38.03°N 89.24°W
Last Update:
3:16 am CST Jan 25, 2026
Forecast Valid:
3am CST Jan 25, 2026-6pm CST Jan 31, 2026
 
Forecast Discussion
 
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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