Flat Lake Weather Forecast

    • 31
    • 42

    Mostly Sunny

    • 35
    • 70

    Mostly Sunny

    • 45
    • 72

    Mostly Sunny

    • 51
    • 78

    Chance Rain

    • 30
    • 63

    Rain Likely

    • 26
    • 43

    Slight Chance Snow

Today 19 Apr McHenry

Sunny. Highs in the mid 40s. Northwest Winds around 5 Mph, becoming southwest in the afternoon.

Tonight 19 Apr McHenry

Increasing Clouds. Not as cold. Lows in the lower 30s. South Winds 10 to 20 Mph.

Graph Plots Open in Graphs

  • Temperature Forecast NOAA

  • Temperature Real-Time

Flat Lake Temperature Statistics

April Temperature

Harvey Municipal Airport (22.4 miles)

  • Lowest 6 April, 2026

    15.8 °F

  • Average April

    35.2 °F

  • Highest 12 April, 2026

    71.6 °F

Climate (2021–Present)

Harvey Municipal Airport (22.4 miles)

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

  • Average Low 2021–2026

    30.3 °F

  • Average 2021–2026

    41.2 °F

  • Average High 2021–2026

    51.9 °F
Get WillyWeather+ to remove ads