Hourly Weather | Today Wednesday, February 4, 2026
Active Weather Warnings
Rancho Cucamonga, California
5 PM
Sunny Weather
79°
Feels Like 73°
0
Humidity: 15%
UV Index: 0
Wind: 18 mph
6 PM
Night
75°
Feels Like 72°
0
Humidity: 17%
UV Index: 0
Wind: 18 mph
7 PM
Cloudy Night
73°
Feels Like 70°
0
Humidity: 20%
UV Index: 0
Wind: 12 mph
8 PM
Cloudy Night
70°
Feels Like 66°
0
Humidity: 22%
UV Index: 0
Wind: 9 mph
9 PM
Cloudy Night
68°
Feels Like 64°
0
Humidity: 25%
UV Index: 0
Wind: 8 mph
10 PM
Cloudy Night
64°
Feels Like 63°
0
Humidity: 27%
UV Index: 0
Wind: 8 mph
11 PM
Cloudy Night
63°
Feels Like 61°
0
Humidity: 30%
UV Index: 0
Wind: 7 mph

Hourly Air Quality Forecast - AQI (US EPA)

5 PM
89 AQI
Moderate air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 30.33 µg/m³
  • PM10: 43 µg/m³
  • O3: 0.060 ppm
  • NO2: 27.7 ppb
  • SO2: 2.7 ppb
  • CO: 0.41 ppm

Health Recommendations:

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

6 PM
83 AQI
Moderate air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 27.54 µg/m³
  • PM10: 39.49 µg/m³
  • O3: 0.055 ppm
  • NO2: 25.4 ppb
  • SO2: 2.7 ppb
  • CO: 0.39 ppm

Health Recommendations:

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

7 PM
78 AQI
Moderate air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 25.19 µg/m³
  • PM10: 36.3 µg/m³
  • O3: 0.051 ppm
  • NO2: 19 ppb
  • SO2: 2.6 ppb
  • CO: 0.37 ppm

Health Recommendations:

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

8 PM
76 AQI
Moderate air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 24.12 µg/m³
  • PM10: 34.64 µg/m³
  • O3: 0.047 ppm
  • NO2: 15.8 ppb
  • SO2: 2.4 ppb
  • CO: 0.37 ppm

Health Recommendations:

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

9 PM
76 AQI
Moderate air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 24.32 µg/m³
  • PM10: 34.61 µg/m³
  • O3: 0.041 ppm
  • NO2: 16.3 ppb
  • SO2: 2.2 ppb
  • CO: 0.39 ppm

Health Recommendations:

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

10 PM
78 AQI
Moderate air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 25.16 µg/m³
  • PM10: 35.63 µg/m³
  • O3: 0.033 ppm
  • NO2: 19.8 ppb
  • SO2: 1.8 ppb
  • CO: 0.43 ppm

Health Recommendations:

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

11 PM
75 AQI
Moderate air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 23.74 µg/m³
  • PM10: 34.31 µg/m³
  • O3: 0.024 ppm
  • NO2: 23.1 ppb
  • SO2: 1.3 ppb
  • CO: 0.45 ppm

Health Recommendations:

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

Weather Alerts and Warnings for Rancho Cucamonga

Moderate Expected Likely

Wind Advisory

Wind Advisory issued February 4 at 12:24PM PST until February 5 at 12:00PM PST by NWS San Diego CA
Feb 4, 12:24 PM Feb 5, 12:00 PM
WHAT: Northeast winds 20 to 30 mph with gusts up to 45 mph
expected. Isolated gusts to 55 mph.

WHERE: Orange County Inland Areas, Riverside County Mountains,
San Bernardino County Mountains, San Bernardino and Riverside
County Valleys-The Inland Empire, San Diego County Mountains, San
Diego County Valleys, San Gorgonio Pass near Banning, and Santa
Ana Mountains and Foothills.

WHEN: Until noon PST Thursday.

IMPACTS: Gusty winds will blow around unsecured objects. Tree
limbs could be blown down and a few power outages may result.
+ Read More
Winds this strong can make driving difficult, especially for high profile vehicles. Use extra caution.
Updated: Feb 4, 3:27 PM Source: NWS Alert

Air Quality Alert

Air Quality Alert issued February 3 at 4:51PM PST by NWS San Diego CA
Feb 3, 4:51 PM Feb 4, 11:00 PM
WHAT: The South Coast AQMD has issued an air quality alert due to
harmful levels of particle pollution from windblown dust. Visit
https://www.aqmd.gov/alertinfo to check current and forecasted air
quality levels.

WHERE: In parts of the Inland Empire, Orange County, and South
Coastal LA County. Levels of particle pollution can vary by time
and location depending on emissions and local weather conditions.

WHEN: Until 11 PM Wednesday.

IMPACTS: Particle pollution can get deep into the lungs and cause
serious health problems such as asthma attacks, heart and lung
disease symptoms, and increased risk of lung infections. Everyone
can be affected, but sensitive groups such as people with lung or
heart disease, older adults, people who are pregnant, children, and
those who spend a lot of time outdoors are at greater risk.
+ Read More
To protect your health, check air quality levels and act as needed: * When Air Quality Index (AQI) levels are "Unhealthy for Sensitive Groups" (orange), sensitive groups as specified above should limit extended or intense outdoor activity. * When AQI is "Unhealthy" (red), everyone may experience health impacts. Sensitive groups should avoid extended time outdoors. * When AQI is "Very Unhealthy" (purple), sensitive groups should avoid all outdoor physical activity. Everyone else should avoid extended or intense outdoor activity. * When AQI is "Hazardous" (maroon), everyone should avoid all outdoor physical activity. * ADDITIONAL DETAILS... To help keep indoor air clean when air quality is poor: * Keep windows and doors closed * Run your air conditioner and/or an air purifier * Do not use whole house fans or swamp coolers that bring in outside air if you have other methods to stay cool * Avoid other sources of pollution such as fireplaces, candles, incense, grilling, and gasoline-powered lawn and garden equipment To help minimize outdoor particle pollution levels: * Carpool, telecommute, reduce trips, or take public transportation * Slow down if driving on dirt roads * Stabilize loose soils
Updated: Feb 4, 3:27 PM Source: NWS Alert