Hourly Weather Forecast for Rancho Cucamonga, California

Hourly Weather | Today › Wednesday, August 5, 2026

Active Weather Warnings

Heat Advisory

Rancho Cucamonga, California

3 AM

66°

Feels Like 66°

Humidity: 79%

UV Index: 0

Wind: 1 mph

4 AM

66°

Feels Like 64°

Humidity: 77%

UV Index: 0

Wind: 0 mph

5 AM

64°

Feels Like 66°

Humidity: 80%

UV Index: 0

Wind: 0 mph

6 AM

64°

Feels Like 66°

Humidity: 82%

UV Index: 0

Wind: 0 mph

7 AM

64°

Feels Like 68°

Humidity: 84%

UV Index: 1

Wind: 0 mph

8 AM

70°

Feels Like 73°

Humidity: 72%

UV Index: 2

Wind: 4 mph

9 AM

75°

Feels Like 81°

Humidity: 61%

UV Index: 3

Wind: 5 mph

10 AM

81°

Feels Like 84°

Humidity: 54%

UV Index: 5

Wind: 5 mph

11 AM

82°

Feels Like 91°

Humidity: 48%

UV Index: 7

Wind: 6 mph

12 PM

88°

Feels Like 93°

Humidity: 41%

UV Index: 10

Wind: 7 mph

1 PM

90°

Feels Like 97°

Humidity: 36%

UV Index: 11

Wind: 8 mph

2 PM

91°

Feels Like 97°

Humidity: 33%

UV Index: 10

Wind: 9 mph

3 PM

93°

Feels Like 97°

Humidity: 31%

UV Index: 7

Wind: 10 mph

4 PM

93°

Feels Like 93°

Humidity: 32%

UV Index: 5

Wind: 12 mph

5 PM

91°

Feels Like 91°

Humidity: 33%

UV Index: 3

Wind: 12 mph

6 PM

90°

Feels Like 88°

Humidity: 36%

UV Index: 2

Wind: 10 mph

7 PM

86°

Feels Like 84°

Humidity: 41%

UV Index: 1

Wind: 9 mph

8 PM

82°

Feels Like 81°

Humidity: 47%

UV Index: 0

Wind: 9 mph

9 PM

81°

Feels Like 79°

Humidity: 53%

UV Index: 0

Wind: 7 mph

10 PM

77°

Feels Like 75°

Humidity: 59%

UV Index: 0

Wind: 6 mph

11 PM

75°

Feels Like 73°

Humidity: 64%

UV Index: 0

Wind: 5 mph

Hourly Air Quality Forecast - AQI (US EPA)

3 AM

36 AQI

Good air quality Dominant pollutant: PM_2.5

Details

Pollutant Concentrations:

PM_2.5: 8.69 µg/m³
PM₁₀: 26.21 µg/m³
O₃: 0.037 ppm
NO₂: 0.8 ppb
SO₂: 0.5 ppb
CO: 0.07 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

4 AM

37 AQI

Good air quality Dominant pollutant: PM_2.5

Details

Pollutant Concentrations:

PM_2.5: 8.86 µg/m³
PM₁₀: 26.93 µg/m³
O₃: 0.037 ppm
NO₂: 0.8 ppb
SO₂: 0.5 ppb
CO: 0.07 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

5 AM

37 AQI

Good air quality Dominant pollutant: PM_2.5

Details

Pollutant Concentrations:

PM_2.5: 8.98 µg/m³
PM₁₀: 27.31 µg/m³
O₃: 0.036 ppm
NO₂: 0.8 ppb
SO₂: 0.5 ppb
CO: 0.07 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

6 AM

38 AQI

Good air quality Dominant pollutant: PM_2.5

Details

Pollutant Concentrations:

PM_2.5: 9.04 µg/m³
PM₁₀: 27.33 µg/m³
O₃: 0.036 ppm
NO₂: 0.9 ppb
SO₂: 0.5 ppb
CO: 0.07 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

7 AM

38 AQI

Good air quality Dominant pollutant: PM_2.5

Details

Pollutant Concentrations:

PM_2.5: 9.15 µg/m³
PM₁₀: 27.52 µg/m³
O₃: 0.036 ppm
NO₂: 1 ppb
SO₂: 0.6 ppb
CO: 0.07 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

8 AM

39 AQI

Good air quality Dominant pollutant: PM_2.5

Details

Pollutant Concentrations:

PM_2.5: 9.3 µg/m³
PM₁₀: 27.89 µg/m³
O₃: 0.036 ppm
NO₂: 1 ppb
SO₂: 0.5 ppb
CO: 0.07 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

9 AM

40 AQI

Good air quality Dominant pollutant: PM_2.5

Details

Pollutant Concentrations:

PM_2.5: 9.53 µg/m³
PM₁₀: 28.15 µg/m³
O₃: 0.036 ppm
NO₂: 0.9 ppb
SO₂: 0.5 ppb
CO: 0.07 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

10 AM

42 AQI

Good air quality Dominant pollutant: PM_2.5

Details

Pollutant Concentrations:

PM_2.5: 9.99 µg/m³
PM₁₀: 28.79 µg/m³
O₃: 0.038 ppm
NO₂: 0.8 ppb
SO₂: 0.5 ppb
CO: 0.07 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

11 AM

45 AQI

Good air quality Dominant pollutant: PM_2.5

Details

Pollutant Concentrations:

PM_2.5: 10.79 µg/m³
PM₁₀: 29.95 µg/m³
O₃: 0.040 ppm
NO₂: 0.6 ppb
SO₂: 0.4 ppb
CO: 0.08 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

12 PM

48 AQI

Good air quality Dominant pollutant: PM_2.5

Details

Pollutant Concentrations:

PM_2.5: 11.49 µg/m³
PM₁₀: 30.99 µg/m³
O₃: 0.042 ppm
NO₂: 0.4 ppb
SO₂: 0.4 ppb
CO: 0.07 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

1 PM

49 AQI

Good air quality Dominant pollutant: PM_2.5

Details

Pollutant Concentrations:

PM_2.5: 11.75 µg/m³
PM₁₀: 31.5 µg/m³
O₃: 0.042 ppm
NO₂: 0.2 ppb
SO₂: 0.3 ppb
CO: 0.07 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

2 PM

49 AQI

Good air quality Dominant pollutant: PM_2.5

Details

Pollutant Concentrations:

PM_2.5: 11.8 µg/m³
PM₁₀: 31.75 µg/m³
O₃: 0.041 ppm
NO₂: 0.2 ppb
SO₂: 0.3 ppb
CO: 0.07 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

3 PM

49 AQI

Good air quality Dominant pollutant: PM_2.5

Details

Pollutant Concentrations:

PM_2.5: 11.81 µg/m³
PM₁₀: 31.9 µg/m³
O₃: 0.040 ppm
NO₂: 0.1 ppb
SO₂: 0.2 ppb
CO: 0.07 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

4 PM

49 AQI

Good air quality Dominant pollutant: PM_2.5

Details

Pollutant Concentrations:

PM_2.5: 11.87 µg/m³
PM₁₀: 31.92 µg/m³
O₃: 0.040 ppm
NO₂: 0.1 ppb
SO₂: 0.2 ppb
CO: 0.07 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

5 PM

50 AQI

Good air quality Dominant pollutant: PM_2.5

Details

Pollutant Concentrations:

PM_2.5: 11.98 µg/m³
PM₁₀: 31.75 µg/m³
O₃: 0.041 ppm
NO₂: 0.2 ppb
SO₂: 0.2 ppb
CO: 0.07 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

6 PM

50 AQI

Good air quality Dominant pollutant: PM_2.5

Details

Pollutant Concentrations:

PM_2.5: 12.02 µg/m³
PM₁₀: 30.94 µg/m³
O₃: 0.041 ppm
NO₂: 0.2 ppb
SO₂: 0.3 ppb
CO: 0.07 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

7 PM

50 AQI

Good air quality Dominant pollutant: PM_2.5

Details

Pollutant Concentrations:

PM_2.5: 12.19 µg/m³
PM₁₀: 30.61 µg/m³
O₃: 0.041 ppm
NO₂: 0.3 ppb
SO₂: 0.3 ppb
CO: 0.07 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

8 PM

51 AQI

Moderate air quality Dominant pollutant: PM_2.5

Details

Pollutant Concentrations:

PM_2.5: 12.43 µg/m³
PM₁₀: 30.61 µg/m³
O₃: 0.041 ppm
NO₂: 0.3 ppb
SO₂: 0.2 ppb
CO: 0.07 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

9 PM

51 AQI

Moderate air quality Dominant pollutant: PM_2.5

Details

Pollutant Concentrations:

PM_2.5: 12.6 µg/m³
PM₁₀: 30.6 µg/m³
O₃: 0.040 ppm
NO₂: 0.2 ppb
SO₂: 0.2 ppb
CO: 0.07 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

10 PM

52 AQI

Moderate air quality Dominant pollutant: PM_2.5

Details

Pollutant Concentrations:

PM_2.5: 12.9 µg/m³
PM₁₀: 31.03 µg/m³
O₃: 0.040 ppm
NO₂: 0.2 ppb
SO₂: 0.2 ppb
CO: 0.07 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

11 PM

53 AQI

Moderate air quality Dominant pollutant: PM_2.5

Details

Pollutant Concentrations:

PM_2.5: 13.39 µg/m³
PM₁₀: 32.11 µg/m³
O₃: 0.039 ppm
NO₂: 0.2 ppb
SO₂: 0.2 ppb
CO: 0.07 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

Current Real-Time Air Quality Report

Weather Alerts and Warnings for Rancho Cucamonga

Moderate Expected Likely

Heat Advisory

Heat Advisory issued August 4 at 9:35PM PDT until August 8 at 8:00PM PDT by NWS San Diego CA

Aug 4, 9:35 PM → Aug 8, 8:00 PM

WHAT: High temperatures in the upper 90s to 105 expected.

WHERE: San Bernardino and Riverside County Valleys-The Inland
Empire.

WHEN: Until 8 PM PDT Saturday.

IMPACTS: Hot temperatures may cause heat illnesses.

+ Read More

Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors.

Updated: Aug 5, 2:02 AM Source: NWS Alert

Hourly Air Quality Forecast - AQI (US EPA)

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Weather Alerts and Warnings for Rancho Cucamonga

Heat Advisory

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