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Today Hourly 7 days 30 days Air Quality
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Hourly Weather | Today › Thursday, December 4, 2025
Active Weather Warnings
Fort Collins, Colorado
4 AM
Foggy Weather
12°
Feels Like 7°
0
Humidity: 97%
Wind: 6 mph
UV Index: 0
5 AM
Foggy Weather
12°
Feels Like 7°
0
Humidity: 99%
Wind: 6 mph
UV Index: 0
6 AM
Foggy Weather
10°
Feels Like 7°
0
Humidity: 97%
Wind: 6 mph
UV Index: 0
7 AM
Foggy Weather
12°
Feels Like 7°
0
Humidity: 90%
Wind: 6 mph
UV Index: 0
8 AM
Foggy Weather
14°
Feels Like 10°
0
Humidity: 80%
Wind: 5 mph
UV Index: 1
9 AM
Foggy Weather
16°
Feels Like 18°
0
Humidity: 90%
Wind: 5 mph
UV Index: 1
10 AM
Foggy Weather
19°
Feels Like 25°
0
Humidity: 89%
Wind: 5 mph
UV Index: 2
11 AM
Foggy Weather
25°
Feels Like 28°
0
Humidity: 81%
Wind: 5 mph
UV Index: 2
12 PM
Foggy Weather
28°
Feels Like 34°
0
Humidity: 72%
Wind: 5 mph
UV Index: 3
1 PM
Cloudy Weather
32°
Feels Like 36°
0
Humidity: 63%
Wind: 5 mph
UV Index: 2
2 PM
Cloudy Weather
36°
Feels Like 37°
0
Humidity: 56%
Wind: 6 mph
UV Index: 2
3 PM
Cloudy Weather
34°
Feels Like 34°
0
Humidity: 59%
Wind: 6 mph
UV Index: 1
4 PM
Cloudy Weather
30°
Feels Like 28°
0
Humidity: 64%
Wind: 6 mph
UV Index: 1
5 PM
Cloudy Night
28°
Feels Like 27°
0
Humidity: 68%
Wind: 6 mph
UV Index: 0
6 PM
Cloudy Night
27°
Feels Like 25°
0
Humidity: 72%
Wind: 6 mph
UV Index: 0
7 PM
Cloudy Weather
27°
Feels Like 23°
0
Humidity: 71%
Wind: 6 mph
UV Index: 0
8 PM
Cloudy Weather
25°
Feels Like 21°
0
Humidity: 70%
Wind: 6 mph
UV Index: 0
9 PM
Cloudy Weather
25°
Feels Like 21°
0
Humidity: 69%
Wind: 6 mph
UV Index: 0
10 PM
Cloudy Weather
25°
Feels Like 19°
0
Humidity: 69%
Wind: 6 mph
UV Index: 0
11 PM
Cloudy Weather
25°
Feels Like 19°
0
Humidity: 67%
Wind: 6 mph
UV Index: 0

Hourly Air Quality Forecast - AQI (US EPA)

4 AM
23 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 2.07 µg/m³
  • PM10: 2.16 µg/m³
  • O3: 0.025 ppm
  • NO2: 3 ppb
  • SO2: 0.1 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

5 AM
23 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 2.04 µg/m³
  • PM10: 2.11 µg/m³
  • O3: 0.024 ppm
  • NO2: 2.8 ppb
  • SO2: 0.1 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

6 AM
22 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.93 µg/m³
  • PM10: 2 µg/m³
  • O3: 0.024 ppm
  • NO2: 2.6 ppb
  • SO2: 0.1 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

7 AM
22 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.84 µg/m³
  • PM10: 1.95 µg/m³
  • O3: 0.024 ppm
  • NO2: 2.6 ppb
  • SO2: 0 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

8 AM
22 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.87 µg/m³
  • PM10: 2 µg/m³
  • O3: 0.024 ppm
  • NO2: 3 ppb
  • SO2: 0 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

9 AM
24 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.77 µg/m³
  • PM10: 1.88 µg/m³
  • O3: 0.026 ppm
  • NO2: 2.5 ppb
  • SO2: 0.1 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

10 AM
25 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.77 µg/m³
  • PM10: 1.88 µg/m³
  • O3: 0.027 ppm
  • NO2: 1.9 ppb
  • SO2: 0.1 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

11 AM
26 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.82 µg/m³
  • PM10: 1.92 µg/m³
  • O3: 0.028 ppm
  • NO2: 1.5 ppb
  • SO2: 0.1 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

12 PM
32 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.23 µg/m³
  • PM10: 1.28 µg/m³
  • O3: 0.034 ppm
  • NO2: 0.7 ppb
  • SO2: 0.1 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.24 µg/m³
  • PM10: 1.29 µg/m³
  • O3: 0.036 ppm
  • NO2: 0.5 ppb
  • SO2: 0.1 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

2 PM
34 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.23 µg/m³
  • PM10: 1.27 µg/m³
  • O3: 0.036 ppm
  • NO2: 0.4 ppb
  • SO2: 0.1 ppb
  • CO: 0.08 ppm

Health Recommendations:

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

3 PM
34 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.09 µg/m³
  • PM10: 1.14 µg/m³
  • O3: 0.037 ppm
  • NO2: 0.4 ppb
  • SO2: 0.1 ppb
  • CO: 0.08 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.97 µg/m³
  • PM10: 1.02 µg/m³
  • O3: 0.036 ppm
  • NO2: 0.7 ppb
  • SO2: 0.2 ppb
  • CO: 0.08 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.89 µg/m³
  • PM10: 0.95 µg/m³
  • O3: 0.036 ppm
  • NO2: 1 ppb
  • SO2: 0.2 ppb
  • CO: 0.08 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.87 µg/m³
  • PM10: 0.93 µg/m³
  • O3: 0.035 ppm
  • NO2: 1.2 ppb
  • SO2: 0.2 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.86 µg/m³
  • PM10: 0.94 µg/m³
  • O3: 0.034 ppm
  • NO2: 1.3 ppb
  • SO2: 0.2 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.86 µg/m³
  • PM10: 0.95 µg/m³
  • O3: 0.034 ppm
  • NO2: 1.3 ppb
  • SO2: 0.1 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.85 µg/m³
  • PM10: 0.95 µg/m³
  • O3: 0.034 ppm
  • NO2: 1.2 ppb
  • SO2: 0.1 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.86 µg/m³
  • PM10: 0.94 µg/m³
  • O3: 0.034 ppm
  • NO2: 1.1 ppb
  • SO2: 0.1 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.86 µg/m³
  • PM10: 0.91 µg/m³
  • O3: 0.035 ppm
  • NO2: 1 ppb
  • SO2: 0.1 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

Current Real-Time Air Quality Report

Weather Alerts and Warnings for Fort Collins

Moderate Expected Likely

Dense Fog Advisory

Dense Fog Advisory issued December 3 at 9:22PM MST until December 4 at 10:00AM MST by NWS Denver CO
Dec 3, 9:22 PM → Dec 4, 10:00 AM
WHAT: Visibility one quarter mile or less in dense fog.

WHERE: Eastern Larimer, Central Weld, and Morgan Counties,
including Fort Collins, Greeley, and Fort Morgan.

WHEN: Until 10 AM MST Thursday.

IMPACTS: Low visibility will make driving conditions hazardous.
+ Read More
If driving, slow down, use your headlights, and leave plenty of distance ahead of you.
Updated: Dec 4, 2:08 AM Source: NWS Alert