Hourly Weather Forecast for Longmont, Colorado

Hourly Weather | Today › Thursday, February 26, 2026

Active Weather Warnings

Fire Weather Watch

Longmont, Colorado

6 AM

45°

Feels Like 37°

Humidity: 47%

UV Index: 0

Wind: 8 mph

7 AM

43°

Feels Like 34°

Humidity: 48%

UV Index: 1

Wind: 14 mph

8 AM

45°

Feels Like 37°

Humidity: 43%

UV Index: 1

Wind: 14 mph

9 AM

48°

Feels Like 45°

Humidity: 36%

UV Index: 2

Wind: 15 mph

10 AM

54°

Feels Like 48°

Humidity: 29%

UV Index: 3

Wind: 16 mph

11 AM

57°

Feels Like 55°

Humidity: 24%

UV Index: 4

Wind: 17 mph

12 PM

61°

Feels Like 57°

Humidity: 20%

UV Index: 4

Wind: 18 mph

1 PM

63°

Feels Like 61°

Humidity: 18%

UV Index: 4

Wind: 16 mph

2 PM

64°

Feels Like 63°

Humidity: 16%

UV Index: 3

Wind: 16 mph

3 PM

63°

Feels Like 61°

Humidity: 16%

UV Index: 2

Wind: 16 mph

4 PM

61°

Feels Like 57°

Humidity: 17%

UV Index: 1

Wind: 15 mph

5 PM

57°

Feels Like 54°

Humidity: 19%

UV Index: 1

Wind: 15 mph

6 PM

55°

Feels Like 50°

Humidity: 22%

UV Index: 0

Wind: 13 mph

7 PM

52°

Feels Like 46°

Humidity: 26%

UV Index: 0

Wind: 10 mph

8 PM

48°

Feels Like 45°

Humidity: 29%

UV Index: 0

Wind: 9 mph

9 PM

46°

Feels Like 41°

Humidity: 33%

UV Index: 0

Wind: 9 mph

10 PM

45°

Feels Like 37°

Humidity: 37%

UV Index: 0

Wind: 10 mph

11 PM

43°

Feels Like 36°

Humidity: 41%

UV Index: 0

Wind: 10 mph

Hourly Air Quality Forecast - AQI (US EPA)

6 AM

28 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 0.5 µg/m³
PM₁₀: 0.67 µg/m³
O₃: 0.030 ppm
NO₂: 0.2 ppb
SO₂: 0.1 ppb
CO: 0.08 ppm

Health Recommendations:

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

7 AM

28 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 0.5 µg/m³
PM₁₀: 0.56 µg/m³
O₃: 0.030 ppm
NO₂: 0.3 ppb
SO₂: 0.1 ppb
CO: 0.08 ppm

Health Recommendations:

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

8 AM

29 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 0.5 µg/m³
PM₁₀: 0.5 µg/m³
O₃: 0.031 ppm
NO₂: 0.3 ppb
SO₂: 0 ppb
CO: 0.08 ppm

Health Recommendations:

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

9 AM

30 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 0.5 µg/m³
PM₁₀: 0.5 µg/m³
O₃: 0.033 ppm
NO₂: 0.2 ppb
SO₂: 0 ppb
CO: 0.08 ppm

Health Recommendations:

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

10 AM

32 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 0.5 µg/m³
PM₁₀: 0.5 µg/m³
O₃: 0.034 ppm
NO₂: 0.2 ppb
SO₂: 0 ppb
CO: 0.08 ppm

Health Recommendations:

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

11 AM

33 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 0.5 µg/m³
PM₁₀: 0.5 µg/m³
O₃: 0.036 ppm
NO₂: 0.1 ppb
SO₂: 0 ppb
CO: 0.08 ppm

Health Recommendations:

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

12 PM

36 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 0.5 µg/m³
PM₁₀: 0.5 µg/m³
O₃: 0.039 ppm
NO₂: 0.1 ppb
SO₂: 0 ppb
CO: 0.08 ppm

Health Recommendations:

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

1 PM

38 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 0.5 µg/m³
PM₁₀: 0.5 µg/m³
O₃: 0.041 ppm
NO₂: 0.1 ppb
SO₂: 0 ppb
CO: 0.08 ppm

Health Recommendations:

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

2 PM

39 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 0.5 µg/m³
PM₁₀: 0.51 µg/m³
O₃: 0.042 ppm
NO₂: 0.1 ppb
SO₂: 0 ppb
CO: 0.08 ppm

Health Recommendations:

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

3 PM

40 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 0.5 µg/m³
PM₁₀: 0.5 µg/m³
O₃: 0.044 ppm
NO₂: 0.1 ppb
SO₂: 0 ppb
CO: 0.08 ppm

Health Recommendations:

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

4 PM

41 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 0.5 µg/m³
PM₁₀: 0.5 µg/m³
O₃: 0.044 ppm
NO₂: 0.1 ppb
SO₂: 0 ppb
CO: 0.08 ppm

Health Recommendations:

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

5 PM

41 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 0.5 µg/m³
PM₁₀: 0.51 µg/m³
O₃: 0.044 ppm
NO₂: 0.1 ppb
SO₂: 0 ppb
CO: 0.08 ppm

Health Recommendations:

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

6 PM

40 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 0.5 µg/m³
PM₁₀: 0.52 µg/m³
O₃: 0.043 ppm
NO₂: 0.3 ppb
SO₂: 0 ppb
CO: 0.08 ppm

Health Recommendations:

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

7 PM

39 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 0.51 µg/m³
PM₁₀: 0.55 µg/m³
O₃: 0.042 ppm
NO₂: 0.4 ppb
SO₂: 0 ppb
CO: 0.09 ppm

Health Recommendations:

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

8 PM

39 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 0.53 µg/m³
PM₁₀: 0.64 µg/m³
O₃: 0.042 ppm
NO₂: 0.5 ppb
SO₂: 0 ppb
CO: 0.09 ppm

Health Recommendations:

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

9 PM

38 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 0.56 µg/m³
PM₁₀: 0.71 µg/m³
O₃: 0.041 ppm
NO₂: 0.5 ppb
SO₂: 0 ppb
CO: 0.09 ppm

Health Recommendations:

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

10 PM

38 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 0.6 µg/m³
PM₁₀: 0.78 µg/m³
O₃: 0.041 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.

11 PM

38 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 0.63 µg/m³
PM₁₀: 0.84 µg/m³
O₃: 0.041 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.

Current Real-Time Air Quality Report

Weather Alerts and Warnings for Longmont

Minor Past Observed

Fire Weather Watch

The Fire Weather Watch has been cancelled.

Feb 26, 11:00 AM → Feb 26, 5:00 PM

The Fire Weather Watch has been cancelled and is no longer in effect.

+ Read More

A Fire Weather Watch means that critical fire weather conditions are forecast to occur. Listen for later forecasts and possible Red Flag Warnings.

Updated: Feb 26, 5:07 AM Source: NWS Alert