Philadelphians could be in store for record high temperatures Monday as the region braces for its second heat wave of the summer.

The National Weather Service says to expect a high temperature in the mid 90s in Philadelphia. That could be put the current record for the date of 95 degrees, set in 2015, in jeopardy.

The high Sunday reached 94 degrees in Philadelphia, the hottest day of the year so far.

And the heat is likely to stick around for at least another day, setting the stage for a three-day heat wave: Forecasters say to expect to another day in the mid-90s on Tuesday. That could threaten the record for June 13, which now stands at 95 degrees, set in 1956.

An air quality alert is in place for the area Monday due to high ozone levels. Officials say air pollution levels are unhealthy for sensitive groups like older people, those with lung disease or asthma, and children.

The region's first heat wave of 2017 was May 17 to 19.

A break from the heat is expected later in the week, with a high temperature in the low-to-mid 80s on Wednesday and highs in the 70s for Thursday and Friday, according to the weather service.

Read more about the steamy weather: