Air quality alert issued in Massachusetts today with record-breaking heat expected

The Massachusetts Department of Environmental Protection has issued an air quality alert today for Boston and other parts of the state with record-high temperatures in the weather forecast.

The alert is in effect from 11 a.m. until 11 p.m. on Tuesday for northeast Massachusetts, the Boston metro area and parts of southeast Massachusetts.

Why is air quality bad today?

"Due to elevated levels of ozone, air quality in these areas are expected to be unhealthy for sensitive groups," the department said. 

At the ground level, ozone is a harmful pollutant that is the main ingredient in smog, according to the Environmental Protection Agency. It's most likely to reach unhealthy levels on hot, sunny days like Tuesday.

Sensitive groups include people with heart or lung disease, asthma, older adults, children, teenagers and people who are active outside, the department said.  

"MassDEP advises people in sensitive groups to reduce prolonged or heavy outdoor exertion, take more breaks, do less intense activities, follow asthma action plans, and keep quick relief medicine handy," the department said. "Watch for symptoms such as coughing or shortness of breath."

Tuesday Boston weather forecast

Tuesday is expected to be the hottest day of the recent warm weather stretch in Boston, as temperatures could soar to about 95 degrees. The record high temperature in Boston for the day is 90 degrees, set in 2017.

Wednesday will be almost as hot, with the temperature expected to reach about 92 in the city. Things will cool down after a cold front pushes through Wednesday afternoon and evening, possibly bringing scattered downpours and thunderstorms to the region.