Hourly Weather | Today › Friday, October 9, 2026
Waltham, Massachusetts
3 PM
Cloudy Weather
66°
Feels Like 66°
47
Humidity: 41%
UV Index: 2
Wind: 15 mph
4 PM
Sunny Weather
68°
Feels Like 66°
35
Humidity: 37%
UV Index: 2
Wind: 13 mph
5 PM
Sunny Weather
66°
Feels Like 64°
19
Humidity: 39%
UV Index: 1
Wind: 12 mph
6 PM
Sunny Weather
63°
Feels Like 61°
19
Humidity: 43%
UV Index: 1
Wind: 10 mph
7 PM
Night
61°
Feels Like 57°
13
Humidity: 48%
UV Index: 0
Wind: 8 mph
8 PM
Cloudy Night
57°
Feels Like 55°
0
Humidity: 55%
UV Index: 0
Wind: 7 mph
9 PM
Cloudy Night
55°
Feels Like 52°
0
Humidity: 59%
UV Index: 0
Wind: 7 mph
10 PM
Cloudy Night
54°
Feels Like 52°
0
Humidity: 62%
UV Index: 0
Wind: 8 mph
11 PM
Cloudy Night
54°
Feels Like 50°
0
Humidity: 64%
UV Index: 0
Wind: 8 mph

Hourly Air Quality Forecast - AQI (US EPA)

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

Pollutant Concentrations:

  • PM2.5: 3.42 µg/m³
  • PM10: 4.49 µg/m³
  • O3: 0.052 ppm
  • NO2: 1 ppb
  • SO2: 0.5 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 3.67 µg/m³
  • PM10: 4.74 µg/m³
  • O3: 0.053 ppm
  • NO2: 1 ppb
  • SO2: 0.5 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 3.64 µg/m³
  • PM10: 4.71 µg/m³
  • O3: 0.052 ppm
  • NO2: 1.3 ppb
  • SO2: 0.5 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 3.43 µg/m³
  • PM10: 4.5 µg/m³
  • O3: 0.048 ppm
  • NO2: 2.4 ppb
  • SO2: 0.5 ppb
  • CO: 0.13 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:

  • PM2.5: 3.05 µg/m³
  • PM10: 4.12 µg/m³
  • O3: 0.042 ppm
  • NO2: 4 ppb
  • SO2: 0.5 ppb
  • CO: 0.14 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 2.51 µg/m³
  • PM10: 3.57 µg/m³
  • O3: 0.037 ppm
  • NO2: 5 ppb
  • SO2: 0.4 ppb
  • CO: 0.15 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: 1.96 µg/m³
  • PM10: 2.98 µg/m³
  • O3: 0.033 ppm
  • NO2: 5.2 ppb
  • SO2: 0.4 ppb
  • CO: 0.15 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.59 µg/m³
  • PM10: 2.55 µg/m³
  • O3: 0.031 ppm
  • NO2: 4.9 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
29 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.37 µg/m³
  • PM10: 2.25 µg/m³
  • O3: 0.031 ppm
  • NO2: 4.3 ppb
  • SO2: 0.3 ppb
  • CO: 0.15 ppm

Health Recommendations:

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