United States Rancho Cucamonga, California
Long Range Weather Forecast

Helping You Avoid Bad Weather. 30 days and beyond.

Rancho Cucamonga, December 2025 Weather Forecast: A Day-by-Day Calendar View Rancho Cucamonga Weather Outlook: Detailed December 2025 Calendar Sun Mon Tue Wed Thu Fri Sat 1 68°F 41°F 20°C 5°C 17% Rancho Cucamonga weather forecast for Dec 1, 2025: 17% Rain Chance, Highs/Lows 68°F to ?68°F Rancho Cucamonga weather forecast for Dec 1, 2025: 17% Rain Chance, Highs/Lows 20°C to ?20°C 2 67°F 39°F 19°C 4°C 30% Rancho Cucamonga weather forecast for Dec 2, 2025: 30% Rain Chance, Highs/Lows 67°F to ?67°F Rancho Cucamonga weather forecast for Dec 2, 2025: 30% Rain Chance, Highs/Lows 19°C to ?19°C 3 66°F 38°F 19°C 3°C 07% Rancho Cucamonga weather forecast for Dec 3, 2025: 7% Rain Chance, Highs/Lows 66°F to ?66°F Rancho Cucamonga weather forecast for Dec 3, 2025: 7% Rain Chance, Highs/Lows 19°C to ?19°C 4 65°F 38°F 18°C 3°C 36% Rancho Cucamonga weather forecast for Dec 4, 2025: 36% Rain Chance, Highs/Lows 65°F to ?65°F Rancho Cucamonga weather forecast for Dec 4, 2025: 36% Rain Chance, Highs/Lows 18°C to ?18°C 5 65°F 38°F 18°C 3°C 48% Rancho Cucamonga weather forecast for Dec 5, 2025: 48% Rain Chance, Highs/Lows 65°F to ?65°F Rancho Cucamonga weather forecast for Dec 5, 2025: 48% Rain Chance, Highs/Lows 18°C to ?18°C 6 66°F 40°F 19°C 4°C 60% Rancho Cucamonga weather forecast for Dec 6, 2025: 60% Rain Chance, Highs/Lows 66°F to ?66°F Rancho Cucamonga weather forecast for Dec 6, 2025: 60% Rain Chance, Highs/Lows 19°C to ?19°C 7 66°F 39°F 19°C 4°C 42% Rancho Cucamonga weather forecast for Dec 7, 2025: 42% Rain Chance, Highs/Lows 66°F to ?66°F Rancho Cucamonga weather forecast for Dec 7, 2025: 42% Rain Chance, Highs/Lows 19°C to ?19°C 8 64°F 38°F 18°C 3°C 22% Rancho Cucamonga weather forecast for Dec 8, 2025: 22% Rain Chance, Highs/Lows 64°F to ?64°F Rancho Cucamonga weather forecast for Dec 8, 2025: 22% Rain Chance, Highs/Lows 18°C to ?18°C 9 63°F 38°F 17°C 3°C 26% Rancho Cucamonga weather forecast for Dec 9, 2025: 26% Rain Chance, Highs/Lows 63°F to ?63°F Rancho Cucamonga weather forecast for Dec 9, 2025: 26% Rain Chance, Highs/Lows 17°C to ?17°C 10 63°F 38°F 17°C 3°C 27% Rancho Cucamonga weather forecast for Dec 10, 2025: 27% Rain Chance, Highs/Lows 63°F to ?63°F Rancho Cucamonga weather forecast for Dec 10, 2025: 27% Rain Chance, Highs/Lows 17°C to ?17°C 11 64°F 38°F 18°C 3°C 35% Rancho Cucamonga weather forecast for Dec 11, 2025: 35% Rain Chance, Highs/Lows 64°F to ?64°F Rancho Cucamonga weather forecast for Dec 11, 2025: 35% Rain Chance, Highs/Lows 18°C to ?18°C 12 65°F 39°F 18°C 4°C 42% Rancho Cucamonga weather forecast for Dec 12, 2025: 42% Rain Chance, Highs/Lows 65°F to ?65°F Rancho Cucamonga weather forecast for Dec 12, 2025: 42% Rain Chance, Highs/Lows 18°C to ?18°C 13 65°F 38°F 18°C 3°C 59% Rancho Cucamonga weather forecast for Dec 13, 2025: 59% Rain Chance, Highs/Lows 65°F to ?65°F Rancho Cucamonga weather forecast for Dec 13, 2025: 59% Rain Chance, Highs/Lows 18°C to ?18°C 14 64°F 38°F 18°C 3°C 40% Rancho Cucamonga weather forecast for Dec 14, 2025: 40% Rain Chance, Highs/Lows 64°F to ?64°F Rancho Cucamonga weather forecast for Dec 14, 2025: 40% Rain Chance, Highs/Lows 18°C to ?18°C 15 64°F 38°F 18°C 3°C 26% Rancho Cucamonga weather forecast for Dec 15, 2025: 26% Rain Chance, Highs/Lows 64°F to ?64°F Rancho Cucamonga weather forecast for Dec 15, 2025: 26% Rain Chance, Highs/Lows 18°C to ?18°C 16 64°F 38°F 18°C 3°C 23% Rancho Cucamonga weather forecast for Dec 16, 2025: 23% Rain Chance, Highs/Lows 64°F to ?64°F Rancho Cucamonga weather forecast for Dec 16, 2025: 23% Rain Chance, Highs/Lows 18°C to ?18°C 17 63°F 38°F 17°C 3°C 40% Rancho Cucamonga weather forecast for Dec 17, 2025: 40% Rain Chance, Highs/Lows 63°F to ?63°F Rancho Cucamonga weather forecast for Dec 17, 2025: 40% Rain Chance, Highs/Lows 17°C to ?17°C 18 65°F 39°F 18°C 4°C 56% Rancho Cucamonga weather forecast for Dec 18, 2025: 56% Rain Chance, Highs/Lows 65°F to ?65°F Rancho Cucamonga weather forecast for Dec 18, 2025: 56% Rain Chance, Highs/Lows 18°C to ?18°C 19 63°F 39°F 17°C 4°C 29% Rancho Cucamonga weather forecast for Dec 19, 2025: 29% Rain Chance, Highs/Lows 63°F to ?63°F Rancho Cucamonga weather forecast for Dec 19, 2025: 29% Rain Chance, Highs/Lows 17°C to ?17°C 20 63°F 38°F 17°C 3°C 21% Rancho Cucamonga weather forecast for Dec 20, 2025: 21% Rain Chance, Highs/Lows 63°F to ?63°F Rancho Cucamonga weather forecast for Dec 20, 2025: 21% Rain Chance, Highs/Lows 17°C to ?17°C 21 63°F 37°F 17°C 3°C 40% Rancho Cucamonga weather forecast for Dec 21, 2025: 40% Rain Chance, Highs/Lows 63°F to ?63°F Rancho Cucamonga weather forecast for Dec 21, 2025: 40% Rain Chance, Highs/Lows 17°C to ?17°C 22 62°F 37°F 17°C 3°C 27% Rancho Cucamonga weather forecast for Dec 22, 2025: 27% Rain Chance, Highs/Lows 62°F to ?62°F Rancho Cucamonga weather forecast for Dec 22, 2025: 27% Rain Chance, Highs/Lows 17°C to ?17°C 23 63°F 38°F 17°C 3°C 52% Rancho Cucamonga weather forecast for Dec 23, 2025: 52% Rain Chance, Highs/Lows 63°F to ?63°F Rancho Cucamonga weather forecast for Dec 23, 2025: 52% Rain Chance, Highs/Lows 17°C to ?17°C 24 62°F 36°F 17°C 2°C 31% Rancho Cucamonga weather forecast for Dec 24, 2025: 31% Rain Chance, Highs/Lows 62°F to ?62°F Rancho Cucamonga weather forecast for Dec 24, 2025: 31% Rain Chance, Highs/Lows 17°C to ?17°C 25 62°F 35°F 17°C 2°C 25% Rancho Cucamonga weather forecast for Dec 25, 2025: 25% Rain Chance, Highs/Lows 62°F to ?62°F Rancho Cucamonga weather forecast for Dec 25, 2025: 25% Rain Chance, Highs/Lows 17°C to ?17°C 26 63°F 36°F 17°C 2°C 36% Rancho Cucamonga weather forecast for Dec 26, 2025: 36% Rain Chance, Highs/Lows 63°F to ?63°F Rancho Cucamonga weather forecast for Dec 26, 2025: 36% Rain Chance, Highs/Lows 17°C to ?17°C 27 66°F 36°F 19°C 2°C 30% Rancho Cucamonga weather forecast for Dec 27, 2025: 30% Rain Chance, Highs/Lows 66°F to ?66°F Rancho Cucamonga weather forecast for Dec 27, 2025: 30% Rain Chance, Highs/Lows 19°C to ?19°C 28 65°F 36°F 18°C 2°C 06% Rancho Cucamonga weather forecast for Dec 28, 2025: 6% Rain Chance, Highs/Lows 65°F to ?65°F Rancho Cucamonga weather forecast for Dec 28, 2025: 6% Rain Chance, Highs/Lows 18°C to ?18°C 29 63°F 36°F 17°C 2°C 31% Rancho Cucamonga weather forecast for Dec 29, 2025: 31% Rain Chance, Highs/Lows 63°F to ?63°F Rancho Cucamonga weather forecast for Dec 29, 2025: 31% Rain Chance, Highs/Lows 17°C to ?17°C 30 62°F 38°F 17°C 3°C 31% Rancho Cucamonga weather forecast for Dec 30, 2025: 31% Rain Chance, Highs/Lows 62°F to ?62°F Rancho Cucamonga weather forecast for Dec 30, 2025: 31% Rain Chance, Highs/Lows 17°C to ?17°C 31 60°F 38°F 16°C 3°C 54% Rancho Cucamonga weather forecast for Dec 31, 2025: 54% Rain Chance, Highs/Lows 60°F to ?60°F Rancho Cucamonga weather forecast for Dec 31, 2025: 54% Rain Chance, Highs/Lows 16°C to ?16°C

Weather Forecast Legend

WeatherTAB helps you plan activities on days with the least risk of rain.
Low risk of rain/snow.
Transition Day – Start or End of a Risky Period
Medium risk of rain/snow.
High risk of rain/snow.
%
Forecast risk of rain/snow.
Rancho Cucamonga Weather Forecast for Dec 2025 - Risk of Rain Graph ) Rancho Cucamonga Weather Forecast for Dec 2025 - Risk of Rain Graph 90 80 70 60 50 40 30 20 10 Dec 1: Precipitation Risk Forecast - 17% risk of rain/snow. /n1 M Dec 2: Precipitation Risk Forecast - 30% risk of rain/snow. /n2 T Dec 3: Precipitation Risk Forecast - 07% risk of rain/snow. /n3 W Dec 4: Precipitation Risk Forecast - 36% risk of rain/snow. /n4 Th Dec 5: Precipitation Risk Forecast - 48% risk of rain/snow. /n5 F Dec 6: Precipitation Risk Forecast - 60% risk of rain/snow. /n6 S Dec 7: Precipitation Risk Forecast - 42% risk of rain/snow. /n7 Sn Dec 8: Precipitation Risk Forecast - 22% risk of rain/snow. /n8 M Dec 9: Precipitation Risk Forecast - 26% risk of rain/snow. /n9 T Dec 10: Precipitation Risk Forecast - 27% risk of rain/snow. /n10 W Dec 11: Precipitation Risk Forecast - 35% risk of rain/snow. /n11 Th Dec 12: Precipitation Risk Forecast - 42% risk of rain/snow. /n12 F Dec 13: Precipitation Risk Forecast - 59% risk of rain/snow. /n13 S Dec 14: Precipitation Risk Forecast - 40% risk of rain/snow. /n14 Sn Dec 15: Precipitation Risk Forecast - 26% risk of rain/snow. /n15 M Dec 16: Precipitation Risk Forecast - 23% risk of rain/snow. /n16 T Dec 17: Precipitation Risk Forecast - 40% risk of rain/snow. /n17 W Dec 18: Precipitation Risk Forecast - 56% risk of rain/snow. /n18 Th Dec 19: Precipitation Risk Forecast - 29% risk of rain/snow. /n19 F Dec 20: Precipitation Risk Forecast - 21% risk of rain/snow. /n20 S Dec 21: Precipitation Risk Forecast - 40% risk of rain/snow. /n21 Sn Dec 22: Precipitation Risk Forecast - 27% risk of rain/snow. /n22 M Dec 23: Precipitation Risk Forecast - 52% risk of rain/snow. /n23 T Dec 24: Precipitation Risk Forecast - 31% risk of rain/snow. /n24 W Dec 25: Precipitation Risk Forecast - 25% risk of rain/snow. /n25 Th Dec 26: Precipitation Risk Forecast - 36% risk of rain/snow. /n26 F Dec 27: Precipitation Risk Forecast - 30% risk of rain/snow. /n27 S Dec 28: Precipitation Risk Forecast - 06% risk of rain/snow. /n28 Sn Dec 29: Precipitation Risk Forecast - 31% risk of rain/snow. /n29 M Dec 30: Precipitation Risk Forecast - 31% risk of rain/snow. /n30 T Dec 31: Precipitation Risk Forecast - 54% risk of rain/snow. /n31 W

Rain Risk Graph: Monthly Overview. Bar heights indicate rain risk percentages. Yellow bars mark low-risk days, while black and grey bars signal higher risks. Grey-yellow bars act as buffers, advising to keep at least one day clear from the riskier grey and black days, guiding safer outdoor planning. Note: This graph suggests potential risk, not guaranteed rainfall; expect most rain, if any, on days marked in grey and black.

Rancho Cucamonga, Dec 2025: Daily High Temperature Forecast Rancho Cucamonga High Temperature Trends for December 2025 65 14 64 14 63 14 62 14 61 14 60 14 59 14 58 14 57 14 Rancho Cucamonga, Dec 1: High Temp of 68°F /nRancho Cucamonga, Dec 1: High Temp of ?°C /n1 M Rancho Cucamonga, Dec 2: High Temp of 67°F /nRancho Cucamonga, Dec 2: High Temp of ?°C /n2 T Rancho Cucamonga, Dec 3: High Temp of 66°F /nRancho Cucamonga, Dec 3: High Temp of ?°C /n3 W Rancho Cucamonga, Dec 4: High Temp of 65°F /nRancho Cucamonga, Dec 4: High Temp of ?°C /n4 Th Rancho Cucamonga, Dec 5: High Temp of 65°F /nRancho Cucamonga, Dec 5: High Temp of ?°C /n5 F Rancho Cucamonga, Dec 6: High Temp of 66°F /nRancho Cucamonga, Dec 6: High Temp of ?°C /n6 S Rancho Cucamonga, Dec 7: High Temp of 66°F /nRancho Cucamonga, Dec 7: High Temp of ?°C /n7 Sn Rancho Cucamonga, Dec 8: High Temp of 64°F /nRancho Cucamonga, Dec 8: High Temp of ?°C /n8 M Rancho Cucamonga, Dec 9: High Temp of 63°F /nRancho Cucamonga, Dec 9: High Temp of ?°C /n9 T Rancho Cucamonga, Dec 10: High Temp of 63°F /nRancho Cucamonga, Dec 10: High Temp of ?°C /n10 W Rancho Cucamonga, Dec 11: High Temp of 64°F /nRancho Cucamonga, Dec 11: High Temp of ?°C /n11 Th Rancho Cucamonga, Dec 12: High Temp of 65°F /nRancho Cucamonga, Dec 12: High Temp of ?°C /n12 F Rancho Cucamonga, Dec 13: High Temp of 65°F /nRancho Cucamonga, Dec 13: High Temp of ?°C /n13 S Rancho Cucamonga, Dec 14: High Temp of 64°F /nRancho Cucamonga, Dec 14: High Temp of ?°C /n14 Sn Rancho Cucamonga, Dec 15: High Temp of 64°F /nRancho Cucamonga, Dec 15: High Temp of ?°C /n15 M Rancho Cucamonga, Dec 16: High Temp of 64°F /nRancho Cucamonga, Dec 16: High Temp of ?°C /n16 T Rancho Cucamonga, Dec 17: High Temp of 63°F /nRancho Cucamonga, Dec 17: High Temp of ?°C /n17 W Rancho Cucamonga, Dec 18: High Temp of 65°F /nRancho Cucamonga, Dec 18: High Temp of ?°C /n18 Th Rancho Cucamonga, Dec 19: High Temp of 63°F /nRancho Cucamonga, Dec 19: High Temp of ?°C /n19 F Rancho Cucamonga, Dec 20: High Temp of 63°F /nRancho Cucamonga, Dec 20: High Temp of ?°C /n20 S Rancho Cucamonga, Dec 21: High Temp of 63°F /nRancho Cucamonga, Dec 21: High Temp of ?°C /n21 Sn Rancho Cucamonga, Dec 22: High Temp of 62°F /nRancho Cucamonga, Dec 22: High Temp of ?°C /n22 M Rancho Cucamonga, Dec 23: High Temp of 63°F /nRancho Cucamonga, Dec 23: High Temp of ?°C /n23 T Rancho Cucamonga, Dec 24: High Temp of 62°F /nRancho Cucamonga, Dec 24: High Temp of ?°C /n24 W Rancho Cucamonga, Dec 25: High Temp of 62°F /nRancho Cucamonga, Dec 25: High Temp of ?°C /n25 Th Rancho Cucamonga, Dec 26: High Temp of 63°F /nRancho Cucamonga, Dec 26: High Temp of ?°C /n26 F Rancho Cucamonga, Dec 27: High Temp of 66°F /nRancho Cucamonga, Dec 27: High Temp of ?°C /n27 S Rancho Cucamonga, Dec 28: High Temp of 65°F /nRancho Cucamonga, Dec 28: High Temp of ?°C /n28 Sn Rancho Cucamonga, Dec 29: High Temp of 63°F /nRancho Cucamonga, Dec 29: High Temp of ?°C /n29 M Rancho Cucamonga, Dec 30: High Temp of 62°F /nRancho Cucamonga, Dec 30: High Temp of ?°C /n30 T Rancho Cucamonga, Dec 31: High Temp of 60°F /nRancho Cucamonga, Dec 31: High Temp of ?°C /n31 W

High Temperature Graph: Tracks daily forecasted highs. Vertical bars on each day highlight forecast variability, emphasizing trend analysis over precise predictions.

Rancho Cucamonga, Dec 2025: Daily Average Temperature Forecast Rancho Cucamonga Average Temperature Trends for December 2025 53 7 52 7 51 7 50 7 49 7 48 7 47 7 46 7 45 7 Rancho Cucamonga, Dec 1: Forecasted Average Temp of 54°F /nRancho Cucamonga, Dec 1: Forecasted Average Temp of 12°C /n1 M Rancho Cucamonga, Dec 2: Forecasted Average Temp of 53°F /nRancho Cucamonga, Dec 2: Forecasted Average Temp of 11°C /n2 T Rancho Cucamonga, Dec 3: Forecasted Average Temp of 52°F /nRancho Cucamonga, Dec 3: Forecasted Average Temp of 11°C /n3 W Rancho Cucamonga, Dec 4: Forecasted Average Temp of 51°F /nRancho Cucamonga, Dec 4: Forecasted Average Temp of 10°C /n4 Th Rancho Cucamonga, Dec 5: Forecasted Average Temp of 51°F /nRancho Cucamonga, Dec 5: Forecasted Average Temp of 10°C /n5 F Rancho Cucamonga, Dec 6: Forecasted Average Temp of 53°F /nRancho Cucamonga, Dec 6: Forecasted Average Temp of 11°C /n6 S Rancho Cucamonga, Dec 7: Forecasted Average Temp of 52°F /nRancho Cucamonga, Dec 7: Forecasted Average Temp of 11°C /n7 Sn Rancho Cucamonga, Dec 8: Forecasted Average Temp of 51°F /nRancho Cucamonga, Dec 8: Forecasted Average Temp of 10°C /n8 M Rancho Cucamonga, Dec 9: Forecasted Average Temp of 50°F /nRancho Cucamonga, Dec 9: Forecasted Average Temp of 10°C /n9 T Rancho Cucamonga, Dec 10: Forecasted Average Temp of 50°F /nRancho Cucamonga, Dec 10: Forecasted Average Temp of 10°C /n10 W Rancho Cucamonga, Dec 11: Forecasted Average Temp of 51°F /nRancho Cucamonga, Dec 11: Forecasted Average Temp of 10°C /n11 Th Rancho Cucamonga, Dec 12: Forecasted Average Temp of 52°F /nRancho Cucamonga, Dec 12: Forecasted Average Temp of 11°C /n12 F Rancho Cucamonga, Dec 13: Forecasted Average Temp of 51°F /nRancho Cucamonga, Dec 13: Forecasted Average Temp of 10°C /n13 S Rancho Cucamonga, Dec 14: Forecasted Average Temp of 51°F /nRancho Cucamonga, Dec 14: Forecasted Average Temp of 10°C /n14 Sn Rancho Cucamonga, Dec 15: Forecasted Average Temp of 51°F /nRancho Cucamonga, Dec 15: Forecasted Average Temp of 10°C /n15 M Rancho Cucamonga, Dec 16: Forecasted Average Temp of 51°F /nRancho Cucamonga, Dec 16: Forecasted Average Temp of 10°C /n16 T Rancho Cucamonga, Dec 17: Forecasted Average Temp of 50°F /nRancho Cucamonga, Dec 17: Forecasted Average Temp of 10°C /n17 W Rancho Cucamonga, Dec 18: Forecasted Average Temp of 52°F /nRancho Cucamonga, Dec 18: Forecasted Average Temp of 11°C /n18 Th Rancho Cucamonga, Dec 19: Forecasted Average Temp of 51°F /nRancho Cucamonga, Dec 19: Forecasted Average Temp of 10°C /n19 F Rancho Cucamonga, Dec 20: Forecasted Average Temp of 50°F /nRancho Cucamonga, Dec 20: Forecasted Average Temp of 10°C /n20 S Rancho Cucamonga, Dec 21: Forecasted Average Temp of 50°F /nRancho Cucamonga, Dec 21: Forecasted Average Temp of 10°C /n21 Sn Rancho Cucamonga, Dec 22: Forecasted Average Temp of 49°F /nRancho Cucamonga, Dec 22: Forecasted Average Temp of 10°C /n22 M Rancho Cucamonga, Dec 23: Forecasted Average Temp of 50°F /nRancho Cucamonga, Dec 23: Forecasted Average Temp of 10°C /n23 T Rancho Cucamonga, Dec 24: Forecasted Average Temp of 49°F /nRancho Cucamonga, Dec 24: Forecasted Average Temp of 9°C /n24 W Rancho Cucamonga, Dec 25: Forecasted Average Temp of 48°F /nRancho Cucamonga, Dec 25: Forecasted Average Temp of 9°C /n25 Th Rancho Cucamonga, Dec 26: Forecasted Average Temp of 49°F /nRancho Cucamonga, Dec 26: Forecasted Average Temp of 9°C /n26 F Rancho Cucamonga, Dec 27: Forecasted Average Temp of 51°F /nRancho Cucamonga, Dec 27: Forecasted Average Temp of 10°C /n27 S Rancho Cucamonga, Dec 28: Forecasted Average Temp of 50°F /nRancho Cucamonga, Dec 28: Forecasted Average Temp of 10°C /n28 Sn Rancho Cucamonga, Dec 29: Forecasted Average Temp of 49°F /nRancho Cucamonga, Dec 29: Forecasted Average Temp of 9°C /n29 M Rancho Cucamonga, Dec 30: Forecasted Average Temp of 50°F /nRancho Cucamonga, Dec 30: Forecasted Average Temp of 10°C /n30 T Rancho Cucamonga, Dec 31: Forecasted Average Temp of 49°F /nRancho Cucamonga, Dec 31: Forecasted Average Temp of 9°C /n31 W

Average Temperature Graph: Illustrates daily average temperatures. Each point's vertical bar underscores the forecast's potential fluctuation, encouraging trend recognition throughout the month.

Rancho Cucamonga, Dec 2025: Daily Low Temperature Forecast Rancho Cucamonga Low Temperature Trends for December 2025 40 0 39 0 38 0 37 0 36 0 35 0 34 0 33 0 32 0 Rancho Cucamonga, December 1: Low Temp of 41°F /nRancho Cucamonga, December 1: Low Temp of 5°C /n1 M Rancho Cucamonga, December 2: Low Temp of 39°F /nRancho Cucamonga, December 2: Low Temp of 4°C /n2 T Rancho Cucamonga, December 3: Low Temp of 38°F /nRancho Cucamonga, December 3: Low Temp of 3°C /n3 W Rancho Cucamonga, December 4: Low Temp of 38°F /nRancho Cucamonga, December 4: Low Temp of 3°C /n4 Th Rancho Cucamonga, December 5: Low Temp of 38°F /nRancho Cucamonga, December 5: Low Temp of 3°C /n5 F Rancho Cucamonga, December 6: Low Temp of 40°F /nRancho Cucamonga, December 6: Low Temp of 4°C /n6 S Rancho Cucamonga, December 7: Low Temp of 39°F /nRancho Cucamonga, December 7: Low Temp of 4°C /n7 Sn Rancho Cucamonga, December 8: Low Temp of 38°F /nRancho Cucamonga, December 8: Low Temp of 3°C /n8 M Rancho Cucamonga, December 9: Low Temp of 38°F /nRancho Cucamonga, December 9: Low Temp of 3°C /n9 T Rancho Cucamonga, December 10: Low Temp of 38°F /nRancho Cucamonga, December 10: Low Temp of 3°C /n10 W Rancho Cucamonga, December 11: Low Temp of 38°F /nRancho Cucamonga, December 11: Low Temp of 3°C /n11 Th Rancho Cucamonga, December 12: Low Temp of 39°F /nRancho Cucamonga, December 12: Low Temp of 4°C /n12 F Rancho Cucamonga, December 13: Low Temp of 38°F /nRancho Cucamonga, December 13: Low Temp of 3°C /n13 S Rancho Cucamonga, December 14: Low Temp of 38°F /nRancho Cucamonga, December 14: Low Temp of 3°C /n14 Sn Rancho Cucamonga, December 15: Low Temp of 38°F /nRancho Cucamonga, December 15: Low Temp of 3°C /n15 M Rancho Cucamonga, December 16: Low Temp of 38°F /nRancho Cucamonga, December 16: Low Temp of 3°C /n16 T Rancho Cucamonga, December 17: Low Temp of 38°F /nRancho Cucamonga, December 17: Low Temp of 3°C /n17 W Rancho Cucamonga, December 18: Low Temp of 39°F /nRancho Cucamonga, December 18: Low Temp of 4°C /n18 Th Rancho Cucamonga, December 19: Low Temp of 39°F /nRancho Cucamonga, December 19: Low Temp of 4°C /n19 F Rancho Cucamonga, December 20: Low Temp of 38°F /nRancho Cucamonga, December 20: Low Temp of 3°C /n20 S Rancho Cucamonga, December 21: Low Temp of 37°F /nRancho Cucamonga, December 21: Low Temp of 3°C /n21 Sn Rancho Cucamonga, December 22: Low Temp of 37°F /nRancho Cucamonga, December 22: Low Temp of 3°C /n22 M Rancho Cucamonga, December 23: Low Temp of 38°F /nRancho Cucamonga, December 23: Low Temp of 3°C /n23 T Rancho Cucamonga, December 24: Low Temp of 36°F /nRancho Cucamonga, December 24: Low Temp of 2°C /n24 W Rancho Cucamonga, December 25: Low Temp of 35°F /nRancho Cucamonga, December 25: Low Temp of 2°C /n25 Th Rancho Cucamonga, December 26: Low Temp of 36°F /nRancho Cucamonga, December 26: Low Temp of 2°C /n26 F Rancho Cucamonga, December 27: Low Temp of 36°F /nRancho Cucamonga, December 27: Low Temp of 2°C /n27 S Rancho Cucamonga, December 28: Low Temp of 36°F /nRancho Cucamonga, December 28: Low Temp of 2°C /n28 Sn Rancho Cucamonga, December 29: Low Temp of 36°F /nRancho Cucamonga, December 29: Low Temp of 2°C /n29 M Rancho Cucamonga, December 30: Low Temp of 38°F /nRancho Cucamonga, December 30: Low Temp of 3°C /n30 T Rancho Cucamonga, December 31: Low Temp of 38°F /nRancho Cucamonga, December 31: Low Temp of 3°C /n31 W

Low Temperature Graph: Displays daily forecasted lows. Vertical rectangles on each plot point indicate forecast uncertainty, aiding in identifying temperature trends rather than exact figures.

December 2025 Summary

Precipitation Forecast
Average Precipitation
Rain Frequency 2 to 4 days
Temperature Forecast
Temperature Forecast Cooler Than Normal
Avg High Temps
Avg Low Temps