Heat wave to burn into next week; how hot will it be

You shouldn't stash the sunscreen just yet, as the record heat that broiled much of the country earlier this summer rolled through the Fourth of July holiday weekend and will continue well into next week.

Much of the Mid-Atlantic region is under a heat advisory issued by the National Weather Service that will last at least through Saturday, July 6, and parts of Delaware, New Jersey and Pennsylvania are lined up to have extended heat waves.

How hot will it be in Delaware?

The string of days in Wilmington, Delaware, with temperatures reaching 90 degrees or higher began on Thursday and will last through Tuesday, July 9, according the National Weather Service's 7-day outlook for Wilmington.

• Saturday, July 6: 94 degrees
• Sunday, July 7: 91 degrees
• Monday, July 8: 92 degrees
• Tuesday, July 9: 90 degrees

The weather service expects 90-degree streak to end on Wednesday, July 10, but it will still be very warm, with temperatures hovering around 89 degrees.

Will there be a heat wave in Philadelphia?

Philadelphia entered the first of its multi-day heat wave on Friday, as the National Weather Service anticipated temperatures to reach 94 degrees and produce a heat index value of 103 degrees.

• Saturday, July 6: 94 degrees
• Sunday, July 7: 92 degrees
• Monday, July 8: 93 degrees
• Tuesday, July 9: 91 ddegrees

Wednesday, July 10 will only be a tick cooler in Philadelphia, but with temperatures expected to reach 89 degrees, there's a chance Philly's hot streak will continue deeper into next week.

How hot will be in South Jersey?

Similarly, temperatures in South Jersey were expected to reach 94 degrees on Friday while producing a heat value index of 102 degrees.

• Saturday, July 6: 94 degrees
• Sunday, July 7: 91 degrees
• Monday, July 8: 93 degrees
• Tuesday, July 9: 92 degrees

Showers and possible thunderstorm will cool things off in South Jersey on Wednesday, July 10, but daytime highs are still expected to reach 89 degrees.

What is a heat wave?

The National Weather Service generally defines a heat wave as three or more consecutive days of temperatures reaching 90 degrees or higher.

The Environmental Protection Agency defines a heat wave as lasting for at least fourdays.

Damon C. Williams is a Philadelphia-based journalist reporting on trending topics across the Mid-Atlantic Region.