The Bottom LineMonday is Jersey heat wave day No. Although at this point, it is more of a “technical” heat wave as not everyone in the state will hit 90 degrees. Monday starts as New Jersey’s coolest morning in five days, since the heat wave began. TuesdayTuesday will be the grand finale of New Jersey’s six-day heat wave, going out with a whimper instead of a bang. (In case you are keeping score, this is the fifth heat wave of the year and tied for the longest of the year.