Heatwave history: Record-breaking heat could hit the Northeast on Friday

Heat, humidity builds across DC area Thursday

The break from the heat and humidity is coming to an end across the D.C. region as temperatures climb back into the 90s on Thursday and are expected to get even hotter on Friday and over the weekend.

WASHINGTON - The Northeast got some reprieve from the sweltering heat this week, but it's about to come to an end with another possible heatwave.

Those 80-degree, low-humidity days are about to spike into the high 90s, which could challenge some heat records across the region.

By the numbers:

Heat advisories have been issued throughout the Northeast, where humidity will make Friday's temperature feel like more than 100 degrees.

Record-breaking heat

In the Philadelphia area, a high of 98 degrees is expected as the heat index soars to 108 for a few hours. That temperature would topple the 1996 record high of 97 degrees!

New York City could also hit 98 degrees tomorrow, and break the 97-degree record set in 1957. However, thanks to humidity, New Yorkers will face feel-like temperatures of 103 degrees.

Temperatures in Washington D.C. are expected to reach the upper 90s, with heat index values peaking near 109 degrees. 

To break the area's heat record, which was set in 1930 and tied in 2016, temperatures would have to hit 100 degrees!

Hottest days this summer

July may be ending with a bang, but it certainly isn't the first time dangerous heat has threatened the region. It could be the fifth heat wave this summer in Philadelphia alone!

Here are some of the hottest days our region has experienced so far this summer:

In New York City, June 24 marked the hottest day in the city since 2012. Temperatures reached a whopping 102 degrees!

June 24 was also the hottest day in Philadelphia and Washington D.C. this summer. 

In Philadelphia, the 101-degree day was the first time the city had hit 100 degrees since 2012. Washington D.C. came close to seeing its first 100-degree day of the year with temperatures reaching 99 degrees.

Big picture view:

FOX Weather says that more than 129 million people across more than 20 states are under life-threatening heat alerts from the South to the East Coast as a large ridge of high pressure builds over the central U.S. this week, commonly referred to as a heat dome.

The system acts like a lid on the atmosphere, trapping heat and leading to prolonged periods of hot, dry weather.