We are in for a repeat of record-breaking heat Wednesday. The high is expected to reach 100 degrees.
Tuesday's oppressive heat climbed to 102 at Philadephia International Airport, marking the third time in 44 years temps hit 102 or higher.
It was July 15, 1995 -- 15 years ago -- when the city last saw temps of 103-degrees.
"This is the fourth heat wave of the season, this is certainly the most extreme," NBC Philadelphia Chief Meteorologist Glenn "Hurricane" Schwartz said.
An excessive heat warning remains in effect until 8 p.m. Wednesday.
"It's the warm nights that help make things even worse the next day," Schwartz says.
Health officials blamed the death of a 92-year-old West Philadelphia woman on Tuesday's heat. The elderly woman was found inside her home by a neighbor who stopped by to check on her.
Authorities said only a single window was cracked on the second floor of the home. The woman's passing is the fifth heat-related death this summer season.
Four people died during the last heat wave just over a week ago, officials said.
The heat caused power and travel problems across the city Tuesday.
SEPTA was forced to slow its regional rail trains during the afternoon rush to prevent overheating the system. Delays reached 45 minutes or higher in the early evening.
An increased demand for cooling power taxed PECO's grid as the company recorded its third-highest usage peak in the utility's history, officials said.
PECO says the company's unofficial peak demand at 5 p.m. Tuesday was 8,832 megawatts -- only 100 megawatts short of the all-time record of 8932 megawatts set in August 2006.
However with the record demand, only a few minor outages were reported.
The Philadelphia Corporation for Aging has its heat hotline in operation until midnight Tuesday. It will reopen on Wednesday at 8:30 a.m.
Residents can call 215.765.9040 for recommended air-conditioned locations, tips on staying cool and how to spot signs of heat stress.
Outdoor pets like dogs are also very prone to heat related illnesses. Veterinarian Dr. Marc Rosenberg of the Voorhees Veterinary Center says it's important to remember that dogs don't sweat.
"You can imagine when it's hot and they can't perspire, it's very hard for them to regulate their temperature," he said.
In mere minutes, your pooch could be put in a dangerous situation. Dr. Rosenberg recommends that if you're bringing your canine outside in the heat to look out for excessive panting, wobbly walking and gagging.
If you have a light-nose or light-eared pup, Dr. Rosenberg says don't be afraid to apply a little sunscreen to prevent sunburn. It's also important to check walking surfaces like sidewalks as dog paws can easily be burned.
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