Hourly Weather | Today Monday, October 27, 2025
Portland, Maine
3 AM
Night
41°
Feels Like 36°
6
Humidity: 83%
Wind: 8 mph
UV Index: 0
4 AM
Cloudy Night
39°
Feels Like 36°
6
Humidity: 84%
Wind: 8 mph
UV Index: 0
5 AM
Cloudy Night
39°
Feels Like 36°
6
Humidity: 85%
Wind: 8 mph
UV Index: 0
6 AM
Cloudy Night
39°
Feels Like 34°
6
Humidity: 85%
Wind: 7 mph
UV Index: 0
7 AM
Cloudy Night
39°
Feels Like 34°
4
Humidity: 87%
Wind: 7 mph
UV Index: 0
8 AM
Cloudy Weather
41°
Feels Like 36°
6
Humidity: 83%
Wind: 8 mph
UV Index: 0
9 AM
Cloudy Weather
43°
Feels Like 39°
6
Humidity: 77%
Wind: 8 mph
UV Index: 1
10 AM
Cloudy Weather
46°
Feels Like 43°
6
Humidity: 71%
Wind: 9 mph
UV Index: 2
11 AM
Cloudy Weather
48°
Feels Like 45°
6
Humidity: 66%
Wind: 11 mph
UV Index: 2
12 PM
Cloudy Weather
50°
Feels Like 46°
6
Humidity: 63%
Wind: 11 mph
UV Index: 3
1 PM
Cloudy Weather
50°
Feels Like 48°
4
Humidity: 61%
Wind: 12 mph
UV Index: 3
2 PM
Cloudy Weather
52°
Feels Like 48°
1
Humidity: 57%
Wind: 12 mph
UV Index: 3
3 PM
Cloudy Weather
50°
Feels Like 48°
1
Humidity: 59%
Wind: 12 mph
UV Index: 2
4 PM
Cloudy Weather
50°
Feels Like 46°
1
Humidity: 60%
Wind: 12 mph
UV Index: 2
5 PM
Cloudy Weather
50°
Feels Like 45°
1
Humidity: 62%
Wind: 12 mph
UV Index: 1
6 PM
Cloudy Night
48°
Feels Like 41°
1
Humidity: 67%
Wind: 11 mph
UV Index: 0
7 PM
Cloudy Night
46°
Feels Like 41°
1
Humidity: 71%
Wind: 9 mph
UV Index: 0
8 PM
Cloudy Night
46°
Feels Like 41°
0
Humidity: 73%
Wind: 9 mph
UV Index: 0
9 PM
Cloudy Night
46°
Feels Like 39°
0
Humidity: 75%
Wind: 9 mph
UV Index: 0
10 PM
Night
45°
Feels Like 39°
0
Humidity: 76%
Wind: 9 mph
UV Index: 0
11 PM
Night
45°
Feels Like 39°
0
Humidity: 77%
Wind: 8 mph
UV Index: 0

Hourly Air Quality Forecast - AQI (US EPA)

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

Pollutant Concentrations:

  • PM2.5: 0.82 µg/m³
  • PM10: 1.61 µg/m³
  • O3: 0.021 ppm
  • NO2: 4.1 ppb
  • SO2: 0.2 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.82 µg/m³
  • PM10: 1.62 µg/m³
  • O3: 0.021 ppm
  • NO2: 3.8 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
19 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 0.84 µg/m³
  • PM10: 1.65 µg/m³
  • O3: 0.021 ppm
  • NO2: 3.6 ppb
  • SO2: 0.3 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.85 µg/m³
  • PM10: 1.68 µg/m³
  • O3: 0.021 ppm
  • NO2: 3.4 ppb
  • SO2: 0.3 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.88 µg/m³
  • PM10: 1.75 µg/m³
  • O3: 0.021 ppm
  • NO2: 3.5 ppb
  • SO2: 0.3 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.99 µg/m³
  • PM10: 2.03 µg/m³
  • O3: 0.020 ppm
  • NO2: 4.2 ppb
  • SO2: 0.3 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.13 µg/m³
  • PM10: 2.35 µg/m³
  • O3: 0.019 ppm
  • NO2: 4.8 ppb
  • SO2: 0.3 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.16 µg/m³
  • PM10: 2.42 µg/m³
  • O3: 0.019 ppm
  • NO2: 4.5 ppb
  • SO2: 0.4 ppb
  • CO: 0.14 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.99 µg/m³
  • PM10: 2.1 µg/m³
  • O3: 0.021 ppm
  • NO2: 3.8 ppb
  • SO2: 0.4 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.51 µg/m³
  • PM10: 0.82 µg/m³
  • O3: 0.028 ppm
  • NO2: 1.9 ppb
  • SO2: 0.3 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.5 µg/m³
  • PM10: 0.63 µg/m³
  • O3: 0.028 ppm
  • NO2: 1.5 ppb
  • SO2: 0.3 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.5 µg/m³
  • PM10: 0.6 µg/m³
  • O3: 0.028 ppm
  • NO2: 1.6 ppb
  • SO2: 0.2 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.5 µg/m³
  • PM10: 0.61 µg/m³
  • O3: 0.028 ppm
  • NO2: 1.8 ppb
  • SO2: 0.3 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.5 µg/m³
  • PM10: 0.73 µg/m³
  • O3: 0.027 ppm
  • NO2: 2.3 ppb
  • SO2: 0.3 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.5 µg/m³
  • PM10: 0.87 µg/m³
  • O3: 0.025 ppm
  • NO2: 3 ppb
  • SO2: 0.4 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.54 µg/m³
  • PM10: 1.09 µg/m³
  • O3: 0.023 ppm
  • NO2: 4.4 ppb
  • SO2: 0.4 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.7 µg/m³
  • PM10: 1.46 µg/m³
  • O3: 0.020 ppm
  • NO2: 6.1 ppb
  • SO2: 0.4 ppb
  • CO: 0.14 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.88 µg/m³
  • PM10: 1.88 µg/m³
  • O3: 0.017 ppm
  • NO2: 7.3 ppb
  • SO2: 0.3 ppb
  • CO: 0.15 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1 µg/m³
  • PM10: 2.18 µg/m³
  • O3: 0.016 ppm
  • NO2: 7.4 ppb
  • SO2: 0.3 ppb
  • CO: 0.15 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1 µg/m³
  • PM10: 2.19 µg/m³
  • O3: 0.016 ppm
  • NO2: 6.6 ppb
  • SO2: 0.3 ppb
  • CO: 0.15 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.94 µg/m³
  • PM10: 2.03 µg/m³
  • O3: 0.017 ppm
  • NO2: 5.7 ppb
  • SO2: 0.3 ppb
  • CO: 0.14 ppm

Health Recommendations:

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