St Charles Weather Forecast

    • 71
    • 87

    Increasing Clouds

    • 68
    • 83

    Rain Showers

    • 66
    • 83

    Partly Sunny

    • 67
    • 84

    Mostly Sunny

    • 65
    • 84

    Slight Chance Thunderstorms

    • 65
    • 83

    Partly Sunny

Today 18 Aug St. Charles

Sunny. Highs in the upper 80s. Southwest Winds around 5 Mph.

Tonight 18 Aug St. Charles

Mostly clear. Near steady temperature in the upper 60s. Light and variable Winds.

Graph Plots Open in Graphs

  • Temperature Forecast NOAA

  • Temperature Real-Time

St Charles Temperature Statistics

August Temperature

St. Louis Lambert International Airport (7.5 miles)

  • Lowest 3 August, 2026

    66.9 °F

  • Average August

    81.8 °F

  • Highest 11 August, 2026

    96.7 °F

Climate (2021–2026)

St. Louis Lambert International Airport (7.5 miles)

Take a look at our website widgetsAvailable free! Find Out More

  • Average Low 2021–2026

    50.7 °F

  • Average 2021–2026

    60.2 °F

  • Average High 2021–2026

    69.7 °F
Get WillyWeather+ to remove ads