Hourly Weather | Today Wednesday, March 18, 2026
Norwalk, Connecticut
8 AM
Cloudy Weather
27°
Feels Like 19°
0
Humidity: 46%
UV Index: 1
Wind: 9 mph
9 AM
Cloudy Weather
28°
Feels Like 25°
0
Humidity: 43%
UV Index: 2
Wind: 9 mph
10 AM
Cloudy Weather
30°
Feels Like 27°
0
Humidity: 41%
UV Index: 3
Wind: 9 mph
11 AM
Cloudy Weather
32°
Feels Like 30°
0
Humidity: 38%
UV Index: 3
Wind: 9 mph
12 PM
Cloudy Weather
34°
Feels Like 36°
0
Humidity: 36%
UV Index: 4
Wind: 8 mph
1 PM
Cloudy Weather
36°
Feels Like 37°
0
Humidity: 34%
UV Index: 5
Wind: 8 mph
2 PM
Cloudy Weather
36°
Feels Like 37°
0
Humidity: 34%
UV Index: 4
Wind: 8 mph
3 PM
Cloudy Weather
37°
Feels Like 36°
0
Humidity: 34%
UV Index: 3
Wind: 8 mph
4 PM
Cloudy Weather
37°
Feels Like 34°
0
Humidity: 33%
UV Index: 2
Wind: 9 mph
5 PM
Cloudy Weather
36°
Feels Like 32°
0
Humidity: 35%
UV Index: 1
Wind: 9 mph
6 PM
Cloudy Weather
36°
Feels Like 30°
0
Humidity: 37%
UV Index: 1
Wind: 8 mph
7 PM
Cloudy Weather
34°
Feels Like 28°
0
Humidity: 42%
UV Index: 0
Wind: 7 mph
8 PM
Cloudy Night
32°
Feels Like 28°
0
Humidity: 47%
UV Index: 0
Wind: 7 mph
9 PM
Cloudy Night
30°
Feels Like 27°
0
Humidity: 53%
UV Index: 0
Wind: 6 mph
10 PM
Cloudy Night
28°
Feels Like 27°
0
Humidity: 58%
UV Index: 0
Wind: 6 mph
11 PM
Cloudy Night
28°
Feels Like 27°
0
Humidity: 59%
UV Index: 0
Wind: 6 mph

Hourly Air Quality Forecast - AQI (US EPA)

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

Pollutant Concentrations:

  • PM2.5: 2.2 µg/m³
  • PM10: 4.58 µg/m³
  • O3: 0.046 ppm
  • NO2: 4.5 ppb
  • SO2: 1.2 ppb
  • CO: 0.16 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.57 µg/m³
  • PM10: 3.59 µg/m³
  • O3: 0.048 ppm
  • NO2: 4.6 ppb
  • SO2: 1 ppb
  • CO: 0.15 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.36 µg/m³
  • PM10: 3.3 µg/m³
  • O3: 0.049 ppm
  • NO2: 4.8 ppb
  • SO2: 0.9 ppb
  • CO: 0.15 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.5 µg/m³
  • PM10: 3.51 µg/m³
  • O3: 0.049 ppm
  • NO2: 4.9 ppb
  • SO2: 0.9 ppb
  • CO: 0.16 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.87 µg/m³
  • PM10: 3.95 µg/m³
  • O3: 0.050 ppm
  • NO2: 4.8 ppb
  • SO2: 0.9 ppb
  • CO: 0.16 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: O3
Details

Pollutant Concentrations:

  • PM2.5: 2.58 µg/m³
  • PM10: 4.73 µg/m³
  • O3: 0.051 ppm
  • NO2: 4.7 ppb
  • SO2: 1 ppb
  • CO: 0.16 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 3.61 µg/m³
  • PM10: 5.86 µg/m³
  • O3: 0.052 ppm
  • NO2: 4.8 ppb
  • SO2: 1 ppb
  • CO: 0.16 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 4.6 µg/m³
  • PM10: 6.89 µg/m³
  • O3: 0.054 ppm
  • NO2: 4.8 ppb
  • SO2: 1.1 ppb
  • CO: 0.16 ppm

Health Recommendations:

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

4 PM
53 AQI
Moderate air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 4.95 µg/m³
  • PM10: 7.12 µg/m³
  • O3: 0.055 ppm
  • NO2: 4.6 ppb
  • SO2: 1 ppb
  • CO: 0.16 ppm

Health Recommendations:

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

5 PM
56 AQI
Moderate air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 4.84 µg/m³
  • PM10: 6.87 µg/m³
  • O3: 0.056 ppm
  • NO2: 4.4 ppb
  • SO2: 0.9 ppb
  • CO: 0.16 ppm

Health Recommendations:

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

6 PM
55 AQI
Moderate air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 4.68 µg/m³
  • PM10: 6.63 µg/m³
  • O3: 0.056 ppm
  • NO2: 4.6 ppb
  • SO2: 0.8 ppb
  • CO: 0.16 ppm

Health Recommendations:

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

7 PM
52 AQI
Moderate air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 4.59 µg/m³
  • PM10: 6.53 µg/m³
  • O3: 0.055 ppm
  • NO2: 4.8 ppb
  • SO2: 0.7 ppb
  • CO: 0.16 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 4.57 µg/m³
  • PM10: 6.55 µg/m³
  • O3: 0.054 ppm
  • NO2: 4.5 ppb
  • SO2: 0.7 ppb
  • CO: 0.16 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 4.72 µg/m³
  • PM10: 6.79 µg/m³
  • O3: 0.053 ppm
  • NO2: 4.2 ppb
  • SO2: 0.6 ppb
  • CO: 0.16 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 4.89 µg/m³
  • PM10: 7.09 µg/m³
  • O3: 0.052 ppm
  • NO2: 4.1 ppb
  • SO2: 0.6 ppb
  • CO: 0.17 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 5.04 µg/m³
  • PM10: 7.4 µg/m³
  • O3: 0.051 ppm
  • NO2: 4 ppb
  • SO2: 0.5 ppb
  • CO: 0.17 ppm

Health Recommendations:

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