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Holliston (Massachusetts) (US)

Air Quality Trend (last 7 days)

Good (0-50)
Moderate (51-100)
Unhealthy for Sensitive Groups (101-150)
Unhealthy (151-200)
Very Unhealthy (201-300)
Hazardous (300+)

Weather - 48h MET Norway

Cloudy
8°C
Cloudy
Humidity
66.6%
Wind
8 m/s
Pressure
1009.4 hPa
Direction
196°
Sunrise
05:00
Sunset
17:00
24h Forecast:
Temp.
0° / 11°
Precip.
31.7mm
Max wind
8.4 m/s

Hourly Forecast

22.03
Now
Weather
8
22.03
17:00
Weather
11°
1
8
22.03
18:00
Weather
10°
1.8
6
22.03
19:00
Weather
0.7
5
22.03
20:00
Weather
10°
0.9
22.03
21:00
Weather
1.1
22.03
22:00
Weather
22.03
23:00
Weather
23.03
00:00
Weather
23.03
01:00
Weather
23.03
02:00
Weather
23.03
03:00
Weather
0.8
23.03
04:00
Weather
1.2
23.03
05:00
Weather
1.3
23.03
06:00
Weather
1.4
23.03
07:00
Weather
2.5
23.03
08:00
Weather
2.1
23.03
09:00
Weather
2.5
23.03
10:00
Weather
3.9
23.03
11:00
Weather
5.1
23.03
12:00
Weather
3.6
23.03
13:00
Weather
1.2
23.03
14:00
Weather
0.5
23.03
15:00
Weather
0.1
5

Temperature

11°C
0°C
16:00
8°C
17:00
11°C
18:00
10°C
19:00
9°C
20:00
10°C
21:00
9°C
22:00
9°C
23:00
9°C
00:00
8°C
01:00
8°C
02:00
7°C
03:00
7°C
04:00
7°C
05:00
5°C
06:00
4°C
07:00
3°C
08:00
2°C
09:00
2°C
10:00
1°C
11:00
1°C
12:00
1°C
13:00
0°C
14:00
0°C
15:00
0°C
16:00 03:00 15:00

Precipitation

5.1mm
0mm
17:00
1mm
18:00
1.8mm
19:00
0.7mm
20:00
0.9mm
21:00
1.1mm
03:00
0.8mm
04:00
1.2mm
05:00
1.3mm
06:00
1.4mm
07:00
2.5mm
08:00
2.1mm
09:00
2.5mm
10:00
3.9mm
11:00
5.1mm
12:00
3.6mm
13:00
1.2mm
14:00
0.5mm
15:00
0.1mm
16:00 03:00 15:00

Wind

8.4m/s
0m/s
16:00
8.4 m/s
17:00
8 m/s
18:00
5.5 m/s
19:00
5.1 m/s
20:00
4.3 m/s
21:00
3.1 m/s
22:00
3.1 m/s
23:00
3.3 m/s
00:00
2.2 m/s
01:00
2.3 m/s
02:00
1.7 m/s
03:00
3.7 m/s
04:00
4.4 m/s
05:00
4.4 m/s
06:00
4.6 m/s
07:00
4.8 m/s
08:00
4.7 m/s
09:00
4.8 m/s
10:00
5 m/s
11:00
4.7 m/s
12:00
4.4 m/s
13:00
5 m/s
14:00
5 m/s
15:00
5.4 m/s
16:00 03:00 15:00

Radiation

No sensor within 100 km.

We display the worst measurements from all stations in the area. This approach provides a more cautious assessment of air quality, accounting for local pollution sources.

AQI
48.7 km
28
9.3%

Measurement time: 2026-03-22 15:55

Calculated from PM2.5/PM10

O3
48.7 km
106.25 µg/m3
66.4%

Measurement time: 2026-03-22 15:55

source: OpenWeatherMap

PM2.5
48.7 km
6.8 µg/m3
8.1%

Measurement time: 2026-03-22 15:55

source: OpenWeatherMap

PM10
48.7 km
10.77 µg/m3
7.7%

Measurement time: 2026-03-22 15:55

source: OpenWeatherMap

CO
48.7 km
0.18786 mg/m3
1.3%

Measurement time: 2026-03-22 15:55

source: OpenWeatherMap

NO2
48.7 km
1.27 µg/m3
0.6%

Measurement time: 2026-03-22 15:55

source: OpenWeatherMap

SO2
48.7 km
0.59 µg/m3
0.2%

Measurement time: 2026-03-22 15:55

source: OpenWeatherMap

About Air Quality in Holliston

Air quality in Holliston is monitored in real-time by sensors and measurement stations. On this page you'll find current data on major air pollutants including particulate matter PM2.5 and PM10, nitrogen dioxide (NO2), ozone (O3), and radiation levels.

Common Pollutants in Holliston

  • PM2.5 - fine particulate matter up to 2.5 micrometers, particularly harmful to health
  • PM10 - particulate matter up to 10 micrometers from traffic and industry
  • NO2 - nitrogen dioxide mainly emitted by vehicles
  • O3 - tropospheric ozone formed in photochemical reactions

When is Air Quality Best in Holliston?

Generally, the best air quality occurs:

  • Early morning (5:00-7:00 AM) before rush hour traffic
  • After rainfall which cleanses the atmosphere
  • During strong winds that disperse pollutants
  • In summer months when heating systems are less used

Tips for Runners in Holliston

If you're planning outdoor activities in Holliston, always check the current AQI value. When AQI exceeds 100, consider moving your workout indoors or shortening the distance. People with respiratory issues, children, and seniors should be especially cautious during elevated pollution levels. Choose routes away from busy streets and industrial areas.