The string of hot and humid days across the tri-state area is about to become an official heat wave.

Beating the heat will become especially difficult on Tuesday. Today’s expected high is 92 degrees, but the humidity will make it feel much warmer.

City Health officials are predicting an air quality index value of 100.

What does that mean? Ozone and air pollution levels will be much higher than normal, particularly this afternoon into the evening.

Exposure to extreme temperatures can lead to heat illness, especially among vulnerable populations like senior citizens and people with chronic medical conditions.

For the second straight day in New York City, cooling centers will be open in all five boroughs to help people avoid the high temperatures.

Ground-level ozone is formed when sunlight and heat interact with smog from vehicle exhausts and industrial and power plant emissions.

In the metro area, the advisory covers the city, Long Island and the Lower Hudson Valley.

CBS 2 HD Meteorologist John Elliott is calling for very sunny conditions on Tuesday, with a slight chance of showers and thunderstorms in the afternoon. It will be hot, with highs in the lower 90s. The problem however will be the low southwest winds, which will keep the hot air stagnant.

(Source: WCBSTV)