Philadelphia region likely to see its first heat wave of summer this week

The hottest weather of the year has reached the Philadelphia region, and it's here to stay for a few days.

While the southern U.S. has seen temperatures from 105 to 110 degrees earlier this week, that same system is bringing the Northeast a forecast in the mid 90s through at least Saturday, said National Weather Service meteorologist Ray Martin.

"It's basically a piece of that very hot air for the Southwest and South Central which is moving into our area today and lingering until Saturday," Martin said Thursday morning.

The summer sizzle could bring the region, including South Jersey, Delaware and Bucks County, its first official heat wave.

Humidity levels above 60% throughout the region will accentuate the heat, leading to significantly higher heat indices — which is what the temperature feels like to the human body — than the number you'll see on your thermometer.

The weather service's issued a heat advisory Thursday morning, in effect until Friday at 6 a.m. with a heat index making it feel like up to 104 degrees, and upped it to an excessive heat warning for Friday, alerting residents to "dangerously hot conditions with heat index values up to 108 expected."

Local officials are working to protect residents against the heat with cooling centers and other efforts.

Montgomery County issued a "Code Red" is in effect until Friday night due to the high heat indices. In Bucks County, officials issued an excessive heat warning in a Thursday morning providing six cooling locations, open 10 a.m. - 6 p.m. until Saturday, for elderly people and people experiencing homelessness. They include the senior centers in Bristol Borough, Bristol Township, Bensalem and Morrisville and the Warminster branch of the YMCA and Riegelsville Borough Hall.

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Chance of storms for Thursday and Saturday

The Philadelphia region could experience severe weather Thursday as a storm-producing disturbance passes through the area, Martin said, and the weather service forecasts Friday as also having a slight chance of thunderstorms at night.

Martin said atmospheric pressure changes make Saturday the most likely day for severe weather this week.

"On Saturday, a cold front will gradually sag through the area, so we'll see another widespread chance of heavy rain and thunderstorms," he said.

Regardless of the chance for severe weather, though, you can trust that the next few days will still be the hottest you've experienced this year.

"We're not expecting a wash-out any of these next few days, because it's not going to hit the low 90s if it's not sunny for at least a while," Martin said.

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What is a heat wave?

Qualifications for "heat waves" vary by region, but Martin said three days in a row of high temperatures in the 90s constitutes a heat wave for the Philadelphia area.

"We are expecting weather in the 90s, so it should be a legitimate heat wave by Saturday," Martin said. "Heat indices will be 100-plus, possibly up to 105, so we have heat advisories today, heat warnings tomorrow."

If high temperatures reach 90 degrees each day through Saturday, it will be the Philadelphia region's first official heat wave this year.

"It's been a bit warm this month not crazy warm, and we actually had a cool May and June going into it. So it's going to feel hot, mainly because we haven't been hot," Martin said.

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How to stay safe in the heat

According to the National Weather Service, heat poses as one of the most dangerous weather-related killers in the United States. While anyone can be vulnerable to heat, the weather service warns that young children and infants, older adults, people with chronic medical conditions and pregnant women all face an increased health risk with high temperatures.

The weather service advises people to never leave a child, disabled person or pet in the car, which can be dangerous even in winter. In 2022 alone, 33 children in the U.S. died in hot cars. It is also possible that children enter a hot car on their own, so the weather service recommends that families with toddlers lock their driveway car's doors to avoid a potential tragedy.

With high heat, it is important to check on people you know who may be vulnerable to the weather, especially if they don't have air conditioning.

According to Heat.gov, the signs of heat exhaustion are dizziness, heavy sweating, nausea, strong thirst and muscle weakness. In order to reduce the risk of a heat stroke, people suffering from these symptoms should move to a cooler area, loosen their clothing, sip cool water an seek medical attention if their symptoms don't improve.

Dealing with a heat stroke, however, is an emergency situation. A victim experiencing a heat stroke may be confused, dizzy, or even fall unconscious, and requires immediate emergency treatment in order to prevent death or permanent disability.

In order to prevent any heat-related injuries, Heat.gov advises people to stay cool, hydrated and informed.

This article originally appeared on Bucks County Courier Times: Forecasters expect heat wave in Philadelphia area this week