Hourly Weather | Today Thursday, February 26, 2026
Costa Mesa, California
2 AM
Cloudy Night
55°
Feels Like 55°
0
Humidity: 95%
UV Index: 0
Wind: 4 mph
3 AM
Cloudy Night
55°
Feels Like 55°
0
Humidity: 95%
UV Index: 0
Wind: 4 mph
4 AM
Cloudy Night
54°
Feels Like 55°
0
Humidity: 96%
UV Index: 0
Wind: 4 mph
5 AM
Cloudy Night
54°
Feels Like 55°
0
Humidity: 95%
UV Index: 0
Wind: 4 mph
6 AM
Cloudy Night
52°
Feels Like 54°
0
Humidity: 100%
UV Index: 0
Wind: 4 mph
7 AM
Cloudy Weather
55°
Feels Like 55°
0
Humidity: 90%
UV Index: 1
Wind: 5 mph
8 AM
Cloudy Weather
57°
Feels Like 61°
0
Humidity: 85%
UV Index: 2
Wind: 5 mph
9 AM
Cloudy Weather
64°
Feels Like 70°
0
Humidity: 71%
UV Index: 3
Wind: 5 mph
10 AM
Cloudy Weather
68°
Feels Like 73°
0
Humidity: 64%
UV Index: 4
Wind: 4 mph
11 AM
Cloudy Weather
72°
Feels Like 77°
0
Humidity: 58%
UV Index: 4
Wind: 5 mph
12 PM
Cloudy Weather
73°
Feels Like 79°
0
Humidity: 52%
UV Index: 5
Wind: 6 mph
1 PM
Cloudy Weather
75°
Feels Like 81°
0
Humidity: 48%
UV Index: 4
Wind: 7 mph
2 PM
Cloudy Weather
79°
Feels Like 81°
0
Humidity: 46%
UV Index: 4
Wind: 7 mph
3 PM
Cloudy Weather
75°
Feels Like 77°
0
Humidity: 48%
UV Index: 3
Wind: 7 mph
4 PM
Cloudy Weather
73°
Feels Like 73°
0
Humidity: 53%
UV Index: 2
Wind: 7 mph
5 PM
Cloudy Weather
72°
Feels Like 70°
0
Humidity: 57%
UV Index: 1
Wind: 6 mph
6 PM
Cloudy Night
70°
Feels Like 66°
0
Humidity: 64%
UV Index: 0
Wind: 5 mph
7 PM
Cloudy Weather
66°
Feels Like 64°
0
Humidity: 70%
UV Index: 0
Wind: 4 mph
8 PM
Cloudy Weather
63°
Feels Like 63°
0
Humidity: 76%
UV Index: 0
Wind: 4 mph
9 PM
Cloudy Weather
61°
Feels Like 61°
0
Humidity: 82%
UV Index: 0
Wind: 4 mph
10 PM
Cloudy Weather
57°
Feels Like 57°
0
Humidity: 88%
UV Index: 0
Wind: 4 mph
11 PM
Cloudy Weather
57°
Feels Like 57°
0
Humidity: 90%
UV Index: 0
Wind: 4 mph

Hourly Air Quality Forecast - AQI (US EPA)

2 AM
32 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 5.1 µg/m³
  • PM10: 11.9 µg/m³
  • O3: 0.034 ppm
  • NO2: 0.8 ppb
  • SO2: 0.2 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

3 AM
31 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 5.35 µg/m³
  • PM10: 12.22 µg/m³
  • O3: 0.033 ppm
  • NO2: 0.9 ppb
  • SO2: 0.2 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 5.53 µg/m³
  • PM10: 12.43 µg/m³
  • O3: 0.033 ppm
  • NO2: 0.9 ppb
  • SO2: 0.2 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 5.74 µg/m³
  • PM10: 12.71 µg/m³
  • O3: 0.032 ppm
  • NO2: 1 ppb
  • SO2: 0.2 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 6.03 µg/m³
  • PM10: 13.11 µg/m³
  • O3: 0.031 ppm
  • NO2: 1.1 ppb
  • SO2: 0.2 ppb
  • CO: 0.13 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:

  • PM2.5: 6.34 µg/m³
  • PM10: 13.54 µg/m³
  • O3: 0.030 ppm
  • NO2: 1.2 ppb
  • SO2: 0.2 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

8 AM
28 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 6.76 µg/m³
  • PM10: 14.02 µg/m³
  • O3: 0.030 ppm
  • NO2: 1.4 ppb
  • SO2: 0.2 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

9 AM
31 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 7.36 µg/m³
  • PM10: 14.53 µg/m³
  • O3: 0.030 ppm
  • NO2: 1.4 ppb
  • SO2: 0.2 ppb
  • CO: 0.14 ppm

Health Recommendations:

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

10 AM
34 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 8.26 µg/m³
  • PM10: 15.34 µg/m³
  • O3: 0.032 ppm
  • NO2: 1.4 ppb
  • SO2: 0.2 ppb
  • CO: 0.14 ppm

Health Recommendations:

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

11 AM
39 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 9.29 µg/m³
  • PM10: 16.39 µg/m³
  • O3: 0.034 ppm
  • NO2: 1.3 ppb
  • SO2: 0.2 ppb
  • CO: 0.15 ppm

Health Recommendations:

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

12 PM
43 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 10.29 µg/m³
  • PM10: 17.55 µg/m³
  • O3: 0.038 ppm
  • NO2: 1 ppb
  • SO2: 0.2 ppb
  • CO: 0.14 ppm

Health Recommendations:

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

1 PM
47 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 11.29 µg/m³
  • PM10: 18.82 µg/m³
  • O3: 0.041 ppm
  • NO2: 0.7 ppb
  • SO2: 0.1 ppb
  • CO: 0.14 ppm

Health Recommendations:

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

2 PM
50 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 12.02 µg/m³
  • PM10: 19.89 µg/m³
  • O3: 0.043 ppm
  • NO2: 0.4 ppb
  • SO2: 0.1 ppb
  • CO: 0.14 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 12.38 µg/m³
  • PM10: 20.51 µg/m³
  • O3: 0.045 ppm
  • NO2: 0.3 ppb
  • SO2: 0.1 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 12.45 µg/m³
  • PM10: 20.78 µg/m³
  • O3: 0.045 ppm
  • NO2: 0.4 ppb
  • SO2: 0.1 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 12.41 µg/m³
  • PM10: 20.81 µg/m³
  • O3: 0.045 ppm
  • NO2: 0.5 ppb
  • SO2: 0.1 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

6 PM
50 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 12.23 µg/m³
  • PM10: 20.71 µg/m³
  • O3: 0.044 ppm
  • NO2: 0.6 ppb
  • SO2: 0.1 ppb
  • CO: 0.13 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: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 12.05 µg/m³
  • PM10: 20.65 µg/m³
  • O3: 0.043 ppm
  • NO2: 0.5 ppb
  • SO2: 0.1 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

8 PM
50 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 12.03 µg/m³
  • PM10: 20.73 µg/m³
  • O3: 0.042 ppm
  • NO2: 0.4 ppb
  • SO2: 0.1 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

9 PM
50 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 12.15 µg/m³
  • PM10: 20.93 µg/m³
  • O3: 0.041 ppm
  • NO2: 0.4 ppb
  • SO2: 0.1 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 12.34 µg/m³
  • PM10: 21.22 µg/m³
  • O3: 0.040 ppm
  • NO2: 0.5 ppb
  • SO2: 0.1 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 12.51 µg/m³
  • PM10: 21.48 µg/m³
  • O3: 0.039 ppm
  • NO2: 0.6 ppb
  • SO2: 0.1 ppb
  • CO: 0.13 ppm

Health Recommendations:

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