Hourly Weather | Today Monday, July 20, 2026
Active Weather Warnings
Centennial, Colorado
4 PM
Cloudy Weather
99°
Feels Like 100°
7
Humidity: 15%
UV Index: 5
Wind: 9 mph
5 PM
Cloudy Weather
97°
Feels Like 97°
7
Humidity: 16%
UV Index: 4
Wind: 9 mph
6 PM
Cloudy Weather
95°
Feels Like 93°
7
Humidity: 17%
UV Index: 2
Wind: 9 mph
7 PM
Cloudy Weather
93°
Feels Like 91°
7
Humidity: 19%
UV Index: 1
Wind: 9 mph
8 PM
Cloudy Weather
90°
Feels Like 88°
7
Humidity: 23%
UV Index: 0
Wind: 8 mph
9 PM
Cloudy Night
86°
Feels Like 82°
7
Humidity: 27%
UV Index: 0
Wind: 8 mph
10 PM
Cloudy Night
82°
Feels Like 81°
7
Humidity: 29%
UV Index: 0
Wind: 8 mph
11 PM
Cloudy Night
79°
Feels Like 75°
7
Humidity: 33%
UV Index: 0
Wind: 8 mph

Hourly Air Quality Forecast - AQI (US EPA)

4 PM
44 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.82 µg/m³
  • PM10: 2.29 µg/m³
  • O3: 0.048 ppm
  • NO2: 0.1 ppb
  • SO2: 0.1 ppb
  • CO: 0.06 ppm

Health Recommendations:

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

5 PM
44 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.71 µg/m³
  • PM10: 2.16 µg/m³
  • O3: 0.048 ppm
  • NO2: 0.1 ppb
  • SO2: 0.1 ppb
  • CO: 0.06 ppm

Health Recommendations:

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

6 PM
44 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.64 µg/m³
  • PM10: 2.11 µg/m³
  • O3: 0.048 ppm
  • NO2: 0.2 ppb
  • SO2: 0.1 ppb
  • CO: 0.06 ppm

Health Recommendations:

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

7 PM
43 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.66 µg/m³
  • PM10: 2.13 µg/m³
  • O3: 0.047 ppm
  • NO2: 0.3 ppb
  • SO2: 0.1 ppb
  • CO: 0.06 ppm

Health Recommendations:

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

8 PM
42 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.68 µg/m³
  • PM10: 2.17 µg/m³
  • O3: 0.045 ppm
  • NO2: 0.4 ppb
  • SO2: 0.1 ppb
  • CO: 0.06 ppm

Health Recommendations:

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

9 PM
40 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.72 µg/m³
  • PM10: 2.25 µg/m³
  • O3: 0.043 ppm
  • NO2: 0.5 ppb
  • SO2: 0.1 ppb
  • CO: 0.06 ppm

Health Recommendations:

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

10 PM
37 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.75 µg/m³
  • PM10: 2.29 µg/m³
  • O3: 0.040 ppm
  • NO2: 0.6 ppb
  • SO2: 0.1 ppb
  • CO: 0.07 ppm

Health Recommendations:

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

11 PM
33 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.78 µg/m³
  • PM10: 2.33 µg/m³
  • O3: 0.036 ppm
  • NO2: 0.9 ppb
  • SO2: 0.1 ppb
  • CO: 0.07 ppm

Health Recommendations:

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

Weather Alerts and Warnings for Centennial

Moderate Expected Likely

Heat Advisory

Heat Advisory issued July 20 at 3:24AM MDT until July 20 at 9:00PM MDT by NWS Denver CO
Jul 20, 3:24 AM Jul 20, 9:00 PM
WHAT: High Temperatures 99 to 103.

WHERE: Fort Collins, Boulder, Denver metro, and Greeley.

WHEN: Until 9 PM MDT this evening.

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. Take extra precautions when outside. Wear lightweight and loose fitting clothing. Try to limit strenuous activities to early morning or evening. To reduce risk during outdoor work, the Occupational Safety and Health Administration recommends scheduling frequent rest breaks in shaded or air conditioned environments. Anyone overcome by heat should be moved to a cool and shaded location. Heat stroke is an emergency! Call 9 1 1.
Updated: Jul 20, 2:01 PM Source: NWS Alert

Air Quality Alert

Air Quality Alert issued July 19 at 8:10PM MDT by NWS Denver CO
Jul 19, 8:10 PM Jul 20, 4:00 PM
The Colorado Department of Public Health and Environment has
issued the following...

WHAT...Ozone Action Day Alert.

WHERE...Douglas, Jefferson, Denver, western Arapahoe, western
Adams, Broomfield, Boulder, Larimer, and Weld Counties

WHEN...400 PM Sunday July 19 to 400 PM Monday July 20

IMPACTS...Ozone Action Day Alert is now in effect for the Front
Range Urban Corridor. Ozone levels are expected to reach the
Unhealthy for Sensitive Groups category on Sunday and Monday in
the northern Colorado Front Range. Elevated levels of ozone are
possible from the Denver Metro area northward, including Fort
Collins and Greeley. For Colorado air quality conditions,
forecasts, and advisories, visit:
https://www.colorado.gov/airquality/colorado_summary.aspx If
possible, please help us reduce ozone pollution by limiting
driving gas and diesel-powered vehicles until at least 4 p.m.
Monday, July 20, 2026. Colorado is also addressing ozone pollution
through state policies. For more information about health impacts
and how ozone pollution forms in Colorado, visit:
https://cdphe.colorado.gov/ozone- pollution-and-your-health

HEALTH INFORMATION...Increasing likelihood of respiratory symptoms
and breathing discomfort in active children and adults and people
with lung disease, such as asthma. Active children and adults, and
people with lung disease, such as asthma, should reduce prolonged
or heavy outdoor exertion.
Updated: Jul 20, 2:01 PM Source: NWS Alert