This is an archived article and the information in the article may be outdated. Please look at the time stamp on the story to see when it was last updated.

NEW YORK — Another day of scorching, possibly record-breaking temperatures has prompted an air quality alert to be issued throughout the five boroughs, Long Island and Westchester, warning New Yorkers to avoid strenuous outdoor activity.

The New York State Department of Environmental Conservation issued the advisory, in effect from 9:58 p.m. Sunday through 10 p.m. Monday, according to the National Weather Service.

It warns of poor air quality throughout New York City, as well as Suffolk, Nassau, Westchester and Rockland counties.

Monday is expected to reach the low 90s in many areas, possibly breaking records.

It is the second day of what will likely be our second heat wave of the season.

A complete change in the jet stream will allow the heat to build in across the entire eastern half of the country. Temperatures will soar into the 90s from the Plains to the east coast.

Sunday reached low 90s, but Monday is expected to see an increase in humidity. This combination will make it the most uncomfortable spell of weather so far this year.

Active children and adults, and people with respiratory problems, such as asthma, are advised to avoid prolonged outdoor activities and those requiring heavy exertion, according to the NYC Office of Emergency Management.

The “very young” and those with pre-existing conditions, such as heart disease, are also at risk, the weather service warns.

People with adverse symptoms should contact their personal physicians, according to the weather service.

The higher-than-normal temperatures increase ozone in the atmosphere. The air quality index on Monday is predicted to be greater than a value of 100 for ozone, the Office of Emergency Management states. The index was created to correlate different pollutants to one scale.

New Yorkers can call a toll-free air quality hotline for more information at 1-800-535-1345.

PIX11’s Chris Brito and Ashley Soley-Cerro contributed to this report.