Fontana Weather Forecast
- 55
- 78
Mostly Sunny
- 56
- 73
Mostly Sunny
- 57
- 74
Mostly Cloudy
- 58
- 70
Chance Rain Showers
- 56
- 67
Chance Rain Showers
- 55
- 65
Chance Rain Showers
Today 26 Oct San Bernardino and Riverside County Valleys-The Inland Empire
Mostly sunny. Highs 76 to 81. Light Winds becoming west to 10 Mph in the afternoon.
Tonight 26 Oct San Bernardino and Riverside County Valleys-The Inland Empire
Mostly clear. Lows 51 to 56. Areas of Winds west to 10 Mph in the evening becoming light.
Fontana Temperature Statistics
October Temperature
Ontario International Airport (8.1 miles)
Lowest 14 October, 2026
52.6 °FAverage October
76.9 °FHighest 5 October, 2026
104.6 °F
Climate (2021–2026)
Ontario International Airport (8.1 miles)
Average Low 2021–2026
55.9 °FAverage 2021–2026
67.3 °FAverage High 2021–2026
79.4 °F