The latest heat wave went out with a bang Sunday afternoon as thunderstorms throughout the region signaled the arrival of a cold front.

The storms brought high winds and drenching rain. Police throughout the region reported downed trees and wires. Accuweather.com reported an 18-degree temperature drop between 3:08 and 4:06 p.m. as dark clouds blanketed Philadelphia and torrents of rain fell.

The storm moved through most areas in about 30 minutes.

The highest wind gust recorded in the city was 46 miles per hour. The worst of the weather was focused on a swath between Lancaster and Allentown, where winds gusted between 60 and 70 m.p.h. and quarter- to golfball-size hail fell, said Justin Povick, a meteorologist with Accuweather.com.

Across the region, fallen trees and branches slowed traffic and took down power lines. Lightning damaged pole-top electrical equipment.

About 45,000 Peco Energy Co. customers lost power, with Bucks and Chester Counties hardest hit. Spokesman Ben Armstrong said he expected power to be restored to most by Monday as crews worked overnight.

In New Jersey, the storm affected 17,000 PSEG customers, including about 4,000 in Burlington and Camden Counties.

Also, 40,000 Atlantic City Electric customers were without power as of 6 p.m. The storm rolled through South Jersey just as crews were reconnecting the last few hundred customers who had lost power Saturday due to heat stress on equipment, spokeswoman Bridget Shelton said.

But the storms ushered in more comfortable weather.

The National Weather Service had extended its excessive-heat warning for the Philadelphia area until 6 p.m. as Sunday's high hit 93 and humidity of 45 percent made that feel like 100.

Monday's high will be around 90, but, because of lower humidity, it might feel like a mere 88 or 89, Povick said.

On Monday night, the low will likely drop below 70 for the first time since July 4.

Two more heat deaths were confirmed in Philadelphia on Sunday, said Jeff Moran, a spokesman for the city Department of Health. That brings the total to 14 for the summer.

Both victims were found by relatives Saturday. The Medical Examiner's Office determined the deaths were heat-related.

One victim was a 90-year-old woman with a history of diabetes and high blood pressure. She had a fan on but kept the windows closed. Moran said only that her zip code was 19147, which is near Society Hill and Queen Village.

The other victim was a 56-year-old man with a history of obesity. He was taken to a hospital and treated for hyperthermia but could not be revived. He lived in the zip code area 19111, in the Northeast.

Delaware County cited heat as a factor in the deaths of two residents last week.

The Delaware County Medical Examiner's Office said hyperthermia contributed to the deaths of 81-year-old Arthur Perry of Havertown and 61-year-old Frank William of Chester.

Officials said Perry was pronounced dead Tuesday, although they did not know exactly when he died, and William was pronounced dead Thursday.

The county said it planned to keep a senior center in Upper Darby open Sunday so the elderly have a cool place to go.

Contact staff writer Stacey Burling at 215-854-4944 or sburling@phillynews.com.
Inquirer staff writer Chelsea Conaboy contributed to this article, which also contains information from the Associated Press.