Extreme heat has again enveloped the tri-state area, prompting the National Weather Service to issue heat advisories through Wednesday.  This week is shaping up to deliver the second heat wave of the summer in New York City,

Extreme heat and humidity return to NYC to start the week, and we could see our second heat wave of the season.

A heat advisory will be in effect for all of north Alabama until 9 p.m. Tuesday. The National Weather Service in Huntsville said the heat index could go as high as 109 across north Alabama both this afternoon and Tuesday.

The Philadelphia region is in the middle of another heat wave as temperatures will hit a high of 95 degrees on Monday.

With this week's heat wave likely leaving conditions feeling like it is more than 100 degrees on Tuesday, Massachusetts could see another big change to the forecast before the week ends.

Temperatures can feel like triple digits this week as a heat wave blankets the greater Philadelphia region. A heat advisory is in effect now through Wednesday, July 30.