Today | Weather | Monday, July 20, 2026

Weather in Somerville, Massachusetts

05:20 PM
Now
Cloudy Weather
82° F
Feels Like 84°
Precipitation 0 %
Wind 8 mph
UV Index (0 - 11+) 3
Humidity 34 %
Today
Cloudy Weather
Day 84°
Night 63°
Precipitation 0 %
Wind 7 mph
UV Index (0 - 11+) 10

Warning: High UV Index Today: 10

High risk of harm from unprotected sun exposure. Take precautions: wear a hat, sunglasses, and apply sunscreen regularly if you’ll be outdoors for extended periods.

Somerville Weather Forecast Updated

6 minutes ago
Last updated on

Air Quality in Somerville

NOW
48 AQI
Good air quality Dominant pollutant: O3

Pollutant Concentrations:

PM2.5 5.1 µg/m³
PM10 6.1 µg/m³
O3 0.052 ppm
NO2 0.6 ppb
SO2 0.3 ppb
CO 0.10 ppm
NH3 0.14 µg/m³
NO 0.19 µg/m³
PM2.5 – Fine particles <2.5μm
PM10 – Inhalable particles <10μm
O3 – Ozone
NO2 – Nitrogen dioxide
SO2 – Sulfur dioxide
CO – Carbon monoxide
NH3 – Ammonia
NO – Nitric oxide

Health Recommendations:

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

Show raw pollutant concentrations (µg/m³)
PM2.55.1 µg/m³
PM106.1 µg/m³
O3101.76 µg/m³
NO21.16 µg/m³
SO20.88 µg/m³
CO108.91 µg/m³
NH30.14 µg/m³
NO0.19 µg/m³