Mount Vernon, IL 62864 Weather

Jefferson County4:31 AM CDT38.32°N, 88.91°W

Current conditions

Clear
41°
Clear
Feels like 41°
High 75°·Low 43° tonight
WindCalm
Humidity100%
Dew point41°
Pressure30.27 inHg
Visibility10 mi
Cloud cover4%
UV index0 Low
Sunrise7:11 AM
Sunset6:11 PM

Observed at Mount Vernon Airport · 1 hr ago

Forecast

10-day

  • Overnight

    Clear, with a low around 43. Wind around 0 mph.

  • Wednesday

    Sunny. High near 75, with temperatures falling to around 73 in the afternoon. North northeast wind around 1 mph.

  • Wednesday Night

    Mostly clear. Low around 46, with temperatures rising to around 48 overnight. Wind around 0 mph.

National Weather Service forecast updated 2 hrs ago.

Hourly

Hourly forecast
  1. Now Clear 45°
  2. 5 AM Clear 44°
  3. 6 AM Sunny 43°
  4. 7 AM Sunny 43°
  5. 8 AM Sunny 45°
  6. 9 AM Sunny 51°
  7. 10 AM Sunny 60°
  8. 11 AM Sunny 64°
  9. 12 PM Sunny 69°
  10. 1 PM Sunny 72°
  11. 2 PM Sunny 73°
  12. 3 PM Sunny 74°
  13. 4 PM Sunny 75°
  14. 5 PM Sunny 73°
  15. 6 PM Mostly Clear 70°
  16. 7 PM Mostly Clear 65°
  17. 8 PM Mostly Clear 58°
  18. 9 PM Mostly Clear 55°
  19. 10 PM Mostly Clear 54°
  20. 11 PM Mostly Clear 53°
  21. Thu12 AM Clear 52°
  22. 1 AM Clear 51°
  23. 2 AM Clear 50°
  24. 3 AM Clear 49°

10-day forecast

Details
  1. TonightOct 20 Clear Clear43°
  2. TodayOct 21 Sunny Sunny46°75°
  3. ThuOct 22 Sunny Sunny45°77°
  4. FriOct 23 Sunny Sunny45°74°
  5. SatOct 24 Sunny Sunny48°75°
  6. SunOct 25 Mostly Sunny Mostly Sunny49°78°
  7. MonOct 26 Partly Sunny Partly Sunny49°76°
  8. TueOct 27 Slight Chance Rain Showers Slight Chance Rain Showers15%71°
  9. WedOct 28 Cloudy Cloudy44°60°
  10. ThuOct 29 Sunny Sunny38°59°

Days after the National Weather Service's seven are MET Norway's outlook, a computer model with no forecaster's review.

Radar

Full map
Open the National Weather Service radar (the map here needs JavaScript).

Weather news near Mount Vernon

More weather news
  • A few showers remaining, chilly weekend ahead

    Rain for some this evening, windy conditions tomorrow, and a cool weekend. (Heartland News) - Most of the shower storm activity has come to an end for the Heartland although a few stronger storms cannot be ruled out for…

    kfvs12.com·5 days ago
  • Another beautiful day ahead for Central Illinois

    DECATUR, Ill. (WAND) – If you’re looking for a reason to get outside, Tuesday is your day. A high-pressure system settling over the Midwest is bringing abundant sunshine and calm winds to Central Illinois, with…

    wandtv.com·23 hrs ago
  • Central Illinois Winter Weather Outlook

    The winter weather outlook for central and southeast Illinois has been released, and a detailed summary is available at this link. Some of the highlights: Current Conditions Latest Observations Daily Climate Maps…

    weather.gov·1 day ago
  • One of the year’s most pleasant weather stretches arrives in Central Illinois

    DECATUR, Ill. (WAND) – A beautiful stretch of sunshine and mild temperatures is settling into the region, and it’s the perfect time to get outside and enjoy it. High pressure is taking control of the Midwest, locking in…

    wandtv.com·2 days ago
  • A great week ahead for Central Illinois

    WAND DECATUR, Ill. (WAND) – A wonderful weekend across Central Illinois carries into the start of the workweek. Overnight lows dip back into the upper 30s tonight with a small risk for patchy frost, though coverage will…

    wandtv.com·2 days ago
  • Sunshine, chilly mornings and a big warm-up ahead for central Illinois

    CENTRAL ILLINOIS (25News Now) - Fall is making an appearance across central Illinois this weekend, but don’t get too comfortable with the chilly temperatures. After a cold start on Sunday morning, sunshine will help…

    25newsnow.com·3 days ago
  • Overnight Frost Advisory for parts of Illinois, NW Indiana

    CBS News Colorado 10pm Saturday CBS News Detroit Weekend 11pm CBS News Los Angeles Weekend 9pm CBS News Philadelphia Weekend 11pm KDKA News Weekend 11pm CBS News Texas Weekend 10pm

    CBS News·3 days ago
  • Frost advisory back in effect for Central Illinois

    WAND DECATUR, Ill. (WAND) – Another cool day starts the weekend across Central Illinois with highs Saturday only reaching the upper 50s under plenty of sunny skies. Strong high pressure remains in control keeping skies…

    wandtv.com·3 days ago
  • Illinois Winter Weather: First Snow Before Thanksgiving, Nov. 26?

    Chicago, IL – Illinois residents wondering when the first measurable snowfall of the 2026 winter season might arrive could see dramatically different conditions depending on where they live. While Chicago typically…

    NewsBreak·4 days ago
  • Frosty Nights Ahead Before a Warm-Up Arrives in Central Illinois

    CENTRAL ILLINOIS (25News Now) - Central Illinois is in for a chilly weekend, with temperatures dropping into the 30s and frost possible overnight. But after a cool start to the weekend, a warming trend will bring…

    25newsnow.com·4 days ago

Sun & moon

Sunrise 7:11 AM
Sunset 6:11 PM
Daylight 10 h 59 min (−2 min 20 s tomorrow)
Waxing Gibbous · 76% lit
Moonrise 3:46 PM Moonset 2:18 AM
Full moon Oct 26 New moon Nov 9

Almanac

Monthly
Normal high / low66° / 43°
Record high88° (1963)
Record low22° (1952)
Wettest2.58 in (1984)
Yesterday72° / 36°
Month to date0.51 in (normal 2.13 in)

Mt Vernon 3 Ne, records since 1895. Normals 1991–2020. Data from NOAA's Regional Climate Centers (ACIS).

Nearby

Forecasters' discussion

From the National Weather Service office in PAH, issued 4 hrs ago

Key Messages

- Patchy fog, potentially dense will continue to be possible this morning near bodies of water.

- Temperatures will remain near to slightly above normal over the next seven days.

- A 15% chance of a sprinkle or isolated rain shower cannot be ruled out on Tuesday afternoon.

Discussion

Issued at 1216 AM CDT Wed Oct 21 2026

A ridge of high pressure will continue to provide abundant sunshine with ample dry weather conditions over the next seven days. The H5 ridge axis nudges more east on Saturday with heights peaking at 588 dm. This translates to daily light northeasterly winds shifting southerly on Saturday, only resulting in a subtle increase in WAA. Daily temperatures will remain near to slightly above normal in the mid to upper 70s, with lows ranging from the mid to upper 40s. Otherwise, patchy fog near bodies of water will remain possible this morning. The only other weather concern is a 15% chance of a sprinkle or isolated rain shower on Tuesday afternoon as a cold front washes out over the FA. While a 0% PoP is currently progged by the NBM, model ensembles support at least a slight mention.

Aviation

Issued at 505 PM CDT Tue Oct 20 2026

Shallow ground fog will again be possible early Wednesday morning, primarily near bodies of water. CGI is most likely terminal to be impacted. Otherwise VFR conditions with calm or very light NE winds and only a few high clouds (primarily in the west).

Pah Watches

IL...None. MO...None. IN...None. KY...None.

Forecasts, observations and alerts in the United States come from the National Weather Service (NOAA); radar from NOAA's Multi-Radar Multi-Sensor system; satellite imagery from NASA's Global Imagery Browse Services (GIBS) and NOAA's GOES satellites; the map from the U.S. Geological Survey's National Map; air quality from AirNow (EPA and its partners); hurricane information from the National Hurricane Center; climate normals and records from NOAA's Regional Climate Centers (ACIS). Forecasts outside the United States and the UV index: MET Norway (CC BY 4.0); observations outside the U.S.: airport reports via NOAA's Aviation Weather Center. Place names: GeoNames (CC BY 4.0). Data are copied on a schedule and may lag the sources; for warnings that affect your safety, follow your local National Weather Service office and emergency officials. Weather news is drawn from the 4Conservative index and reflects what the press published. Terms of use.