Alta Loma Weather Forecast

    • 46
    • 66

    Increasing Clouds

    • 46
    • 69

    Mostly Sunny

    • 48
    • 70

    Partly Sunny

    • 48
    • 69

    Partly Sunny

    • 48
    • 70

    Mostly Sunny

    • 50
    • 73

    Mostly Sunny

Today 25 Jan San Bernardino and Riverside County Valleys-The Inland Empire

Mostly sunny in the morning. Becoming partly cloudy. Highs 63 to 69. Areas of Winds north 15 to 25 Mph with Gusts to 45 Mph. Becoming 10 to 15 Mph with Gusts to 30 Mph in the afternoon.

Tonight 25 Jan San Bernardino and Riverside County Valleys-The Inland Empire

Partly cloudy. Lows around 40 in wind Sheltered Areas to 41 to 46 in warmer Locations. Areas of Winds east 10 to 20 Mph. Gusts to 30 Mph. Becoming 35 Mph overnight.

Graph Plots Open in Graphs

  • Temperature Forecast NOAA

  • Temperature Real-Time

Alta Loma Temperature Statistics

January Temperature

Ontario International Airport (4.3 miles)

  • Lowest 11 January, 2026

    39.7 °F

  • Average January

    59.7 °F

  • Highest 14 January, 2026

    84.7 °F

Climate (2021–Present)

Ontario International Airport (4.3 miles)

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

  • Average Low 2021–2026

    55.6 °F

  • Average 2021–2026

    66.6 °F

  • Average High 2021–2026

    78.9 °F
Get WillyWeather+ to remove ads