Today | Weather | Thursday, July 16, 2026

Active Weather Warnings

Air Quality Alert

Weather in Cambridge, Massachusetts

03:48 AM

Now

66° F

Feels Like 64°

Precipitation 0 %

Wind 7 mph

Humidity 67 %

Today

Day 90°

Night 64°

Precipitation 3 %

Wind 16 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.

Cambridge Weather Forecast Updated

22 minutes ago

Last updated on July 16, 2026 at 3:25 AM

Weather Forecast History

Last Year's Weather on This Day (July 16, 2025)

Day

90°

Night

75°

Wind

7 mph

UV Index

Precipitation

25 %

Air Quality in Cambridge

NOW

120 AQI

Unhealthy air quality for sensitive groups Dominant pollutant: PM_2.5

Pollutant Concentrations:

PM_2.5 43.53 µg/m³

PM₁₀ 44.17 µg/m³

O₃ 0.033 ppm

NO₂ 2.4 ppb

SO₂ 0.3 ppb

CO 0.53 ppm

NH₃ 3.53 µg/m³

NO 0 µg/m³

PM_2.5 – 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:

Members of sensitive groups may experience health effects. The general public is not likely to be affected.

Show raw pollutant concentrations (µg/m³)

PM_2.5 – 43.53 µg/m³

PM₁₀ – 44.17 µg/m³

O₃ – 63.91 µg/m³

NO₂ – 4.5 µg/m³

SO₂ – 0.67 µg/m³

CO – 602.86 µg/m³

NH₃ – 3.53 µg/m³

NO – 0 µg/m³

View Hourly Air Quality Forecast

Weather Alerts and Warnings for Cambridge

Air Quality Alert

Air Quality Alert issued July 15 at 4:34PM EDT by NWS Boston/Norton MA

Jul 15, 4:34 PM → Jul 16, 12:00 PM

The Massachusetts Department of Environmental Protection has issued
an Air Quality Alert for Fine Particulates, until midnight EDT
Thursday night.

An Air Quality Alert day means that Fine Particulates concentrations
within the region may approach or exceed levels that are Unhealthy
for Sensitive Groups.

Air is unhealthy for sensitive children and adults, such as those
with asthma, lung or heart disease, and older adults. Sensitive
children and adults should limit prolonged outdoor activity.

For additional information, please visit the Massachusetts
Department of Environmental Protection website at:
https://mass.gov/dep/massair/forecast

Updated: Jul 16, 3:25 AM Source: NWS Alert