PHILADELPHIA - Summer temperatures are making a return as heat and humidity rebound in the Delaware Valley.
Moisture from the ground as a result of Monday night rain is causing dense fog and low visibility in parts of the area Tuesday morning.
Areas north of Philadelphia are under a dense fog advisory until 9 a.m. FOX 29's Sue Serio says there's a 20 - 30% chance of a late afternoon thunderstorm moving through the Philadelphia area.
Looking ahead, Tuesday's temperatures are expected to reach 86 degrees before they rise back to the 90s Wednesday through Friday.