Mascoutah, IL Weather

Saint Clair County2:37 AM CDT38.49°N, 89.79°WElevation 430 ft

Current conditions

Mostly Clear
51°
Mostly Clear
Feels like 51°
High 76°·Low 46° tonight
WindSE 2 mph
Humidity86%
Dew point47°
Cloud cover20%
Sunrise7:18 AM
Sunset6:10 PM

Forecast for this hour (no station report in the last two hours)

Forecast

10-day
  • Friday Night

    Mostly clear, with a low around 46.

  • Saturday

    Mostly sunny, with a high near 76.

  • Saturday Night

    Partly cloudy, with a low around 48.

National Weather Service forecast updated 2 days ago.

  1. Now Mostly Clear 51°
  2. 3 AM Mostly Clear 49°
  3. 4 AM Mostly Clear 48°
  4. 5 AM Mostly Clear 47°
  5. 6 AM Sunny 46°
  6. 7 AM Sunny 46°
  7. 8 AM Sunny 50°
  8. 9 AM Sunny 55°
  9. 10 AM Sunny 60°
  10. 11 AM Sunny 65°
  11. 12 PM Mostly Sunny 70°
  12. 1 PM Mostly Sunny 73°
  13. 2 PM Mostly Sunny 76°
  14. 3 PM Mostly Sunny 76°
  15. 4 PM Mostly Sunny 76°
  16. 5 PM Mostly Sunny 74°
  17. 6 PM Partly Cloudy 70°
  18. 7 PM Partly Cloudy 66°
  19. 8 PM Partly Cloudy 63°
  20. 9 PM Partly Cloudy 59°
  21. 10 PM Partly Cloudy 57°
  22. 11 PM Partly Cloudy 56°
  23. Sun12 AM Partly Cloudy 55°
  24. 1 AM Mostly Cloudy 54°

10-day forecast

Details
  1. WedOct 21 Sunny Sunny46°75°
  2. ThuOct 22 Sunny Sunny47°77°
  3. FriOct 23 Sunny Sunny46°75°
  4. TodayOct 24 Mostly Sunny Mostly Sunny48°76°
  5. SunOct 25 Mostly Sunny Mostly Sunny49°78°
  6. MonOct 26 Partly Sunny Partly Sunny50°76°
  7. TueOct 27 Slight Chance Rain Showers Slight Chance Rain Showers15%45°68°
  8. WedOct 28 Partly cloudy Partly cloudy52°79°
  9. ThuOct 29 Rain Rain0.20 in50°75°
  10. FriOct 30 Sunny Sunny40°62°

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 Mascoutah

More weather news
  • Tracking a cool night, pleasant Tuesday

    TONIGHT: Mostly clear and cool with lows in the mid-40s. TOMORROW: Mostly sunny and mild with highs in the lower 70s. EXTENDED: We'll be cool again overnight as temperatures fall to the mid-40s. We'll see gradual…

    ABC17NEWS·4 days ago
  • St. Louis Weather Forecast Friday Through Thursday

    St. Louis is trading late-summer warmth for a blustery fall reset Friday: mostly cloudy skies, a high near 55, and northwest winds around 17 mph with gusts up to 33 mph. A few rain showers could move through after 3…

    Hoodline·5 days ago
  • First Alert Weather Day Today: Low Severe Storm Chance 2 - 7PM

    KMOV - Outlying Areas Could See Frost Saturday AM and Sunday AM Today: Expect lots of cloud cover today with temperatures nearing 80°. Isolated Severe Storms Remain Possible this Afternoon from 2PM- 7PM: This is a…

    firstalert4.com·8 days ago
  • Damaging Winds Possible in Illinois and Missouri Thursday

    Parts of Missouri and most of Illinois are likely to experience the type of thunderstorm you'd expect to see during the Spring months. Forecasters are warning of a possible damaging wind event that will likely leave…

    100.9 The Eagle·9 days ago
  • This week's record heat caps hottest Jan.-Sept. on record in US

    If it feels like summer never left, the numbers back you up. This week brought a fresh wave of record-breaking heat across the country, even as calendars flip toward Halloween. In a word: hot. According to U.S. National…

    Yahoo News·9 days ago
  • Will colorful fall foliage peak soon in the metro-east? When to leaf peep

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    Belleville News-Democrat·9 days ago
  • Daily high-temperature records broken or tied on October 13 across parts of the central U.S.

    Five daily high-temperature records were broken and one was tied at six sites across Kansas, Oklahoma, Missouri and Illinois on October 13, 2026. Temperatures at the sites reached 32.8–33.9°C (91–93°F), or 9.4–13.3°C…

    The Watchers·9 days ago
  • Tracking storms with heavy rain moving in late tonight

    TONIGHT: Warm with storms arriving late. Some storms may produce heavy rain and strong wind gusts. Lows in the upper 60s. TOMORROW: Rain and storms likely early, becoming more scattered by afternoon. Highs in the upper…

    ABC17NEWS·10 days ago
  • Illinois to get brief taste of fall weather this week

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    FarmWeekNow·10 days ago
  • A big cooldown will drop temperatures to their lowest levels in months

    A view of the Manhattan skyline illuminated at night, with autumn foliage in the foreground along the East River in New York City, on October 12. People visit Taughannock Falls State Park in Ithaca, New York, on October…

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Air quality

61
Moderate
Fine particles (PM2.5)

Acceptable. Unusually sensitive people should consider limiting prolonged outdoor exertion.

Forecast

  • SatModerate
  • SunModerate
  • MonModerate

St. Louis (Metro-east), IL reporting area · 1 hr ago. Data from AirNow (EPA and its state, local and tribal partners); preliminary and subject to change.

Sun & moon

Sunrise 7:18 AM
Sunset 6:10 PM
Daylight 10 h 52 min (−2 min 19 s tomorrow)
Waxing Gibbous · 96% lit
Moonrise 5:01 PM Moonset 5:34 AM
Full moon Oct 26 New moon Nov 9

Almanac

Monthly
Normal high / low69° / 44°
Month to date0.96 in (normal 2.18 in)

Belleville Siu Research, records since 1948. Normals 1991–2020. Data from NOAA's Regional Climate Centers (ACIS).

Nearby

Forecasters' discussion

From the National Weather Service office in LSX, issued 2 hrs ago

Key Messages

- High pressure remains in place allowing for our dry and warm weather continues well into next week.

Short Term

Issued at 148 PM CDT Fri Oct 23 2026

An upper-level ridge will remain positioned over the Mid-Mississippi River Valley through Sunday, stagnated by the configuration of the wave pattern into an Omega Block. This pattern will result in very little change in sensible weather from day to day with seasonably warm temperatures and dry conditions. The only change through the weekend will be the very slow departure of a surface high pressure center and upper-level clouds of varying thickness streaming overhead by Saturday through Sunday. The most pronounced nocturnal radiational cooling during the period will be across southeastern MO/southwestern IL and/or river valleys with low temperatures in the 40s F and patchy morning fog, mainly low temperatures in the 50s F elsewhere. High temperatures will continue to be in the 70s F, near 80 F on Sunday depending on the thickness of cloud cover.

Long Term

Issued at 148 PM CDT Fri Oct 23 2026

Global model guidance is coming into better agreement on the ejection of an upper-level trough into the Central/Northern Plains and Upper Midwest Monday through Tuesday as the Omega Block breaks down. With this track of the trough, it is increasingly likely that the associated cold front does not reach the CWA, favoring similar, seasonably warm temperatures continuing along with dry conditions.

It is not until late next week now, that there are any signs for our sensible weather to change with varying signals for an upper-level trough to propagate into the north-central CONUS. However, the track and amplitude of the trough is uncertain which will influence its ability to force an associated cold front east/southeastward. If the front reaches the CWA, it would be accompanied by an opportunity for rain and temperatures cooling closer to average late next week. If the front fails to reach the CWA, there would be no clear catalyst for seasonably warm temperatures and dry conditions to end. Ensemble model guidance cluster analysis depicts these scenarios all being valid possible outcomes at this point. Taking all scenarios into consideration, probabilities of measurable rainfall range from 20 to 50 percent Thursday, onward, along with NBM interquartile ranges increasing to between 10 and 20 F.

Aviation

Issued at 1220 AM CDT Sat Oct 24 2026

High pressure continues to bring calm winds and VFR conditions. There continues to be a daily threat of fog in the valleys each morning, but thus far some high level cirrus clouds are providing enough of a blanket tonight to make this less likely than previous nights. However, if these clouds disperse then locally greater cooling may lead to local instances of fog through 12 or 13Z. The greatest chances are at SUS or CPS.

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 4Search index and reflects what the press published. Terms of use.