Temperatures will make a run at a record Saturday afternoon as this dangerous heat wave crests and bakes the region to a rarefied level of discomfort.

“It’s looking very well like we’ll get to 100,” said Lee Robertson, a meteorologist with the National Weather Service office in Mount Holly, which has posted an excessive heat warning for the entire region until 11 p.m. Sunday, a day when temperatures could again approach 100 degrees.

The sultry atmospheric soup could make it feel like 115 this weekend, though the mercury had already climbed to 81 degrees in Philly with a heat index of 88 by 6 a.m. Saturday, according to the NWS.

At the New Jersey Shore, the ocean could become quite crowded, but a land breeze isn’t going to offer much relief. You might try Miami or Phoenix, where the forecast heat indexes could be 20 to 25 degrees lower than here.

Yes, it’s July, but we’re not quite used to this. For a variety of reasons — it tends to be humid around here, so some of the sun’s energy is diverted to evaporating water vapor — triple-digit temperatures in Philadelphia are unusual.

The official reading at Philadelphia International Airport hasn’t hit 100 since July 2012. The record for a July 20 is 99, set in 1930.

The temperature could get no lower than 80 Saturday morning, was just a degree below the record-high minimum temperature for the date. The forecast low for Sunday 82, would set a record.

Health officials warn that people who don’t have air-conditioning, especially seniors who live alone, are especially vulnerable. Effects accumulate as hot weather continues, and lack of nighttime cooling exacerbates them. Plus, when houses don’t cool off at night, they reheat in a hurry after daybreak.

“Research shows that overnight cooling is necessary to recover from daytime temperatures,” said Paul Schramm, a heat-health scientist at the Centers for Disease Control and Prevention in Atlanta.

High pressure off the Atlantic Coast is importing steamy subtropical air; winds circulate clockwise around high centers, so areas to the west experience winds from the south and southwest. Heat warnings have been issued from North Carolina to New Hampshire, and from Ohio westward to Nebraska.

Red indicates areas of National Weather Service's heat warnings.
Red indicates areas of National Weather Service's heat warnings.

The warnings cover all of New Jersey and most of Eastern Pennsylvania.

A heat health emergency also remains in effect in the city, and residents are asked to check on elderly neighbors. (The Philadelphia Corp. for Aging’s Heatline can be reached at 215-765-9040 for information and assistance.)

In West Philadelphia, residents of a senior high-rise were evacuated Friday morning after a partial power shortage cut off air-conditioning at the 12-story Pavilion Apartment at 3901 Conshohocken Ave. No injuries were reported.

Nijaz Hasanagic, 80, stands outside the Pavilion Apartments in Wynnefield Heights where residents of the 12-story senior complex were evacuated after a partial power outage knocked out air conditioning.
TYGER WILLIAMS / Staff Photographer
Nijaz Hasanagic, 80, stands outside the Pavilion Apartments in Wynnefield Heights where residents of the 12-story senior complex were evacuated after a partial power outage knocked out air conditioning.

Not surprisingly, on Friday some Philadelphians were making escape plans. But others appeared comfortable with what lay ahead.

Simoni and Gregory Bonadies, both 53, were visiting the area for the first time, with plans to see the Philadelphia Museum of Art and its iconic Rocky steps. But the Central Florida couple are used to the heat.

“This is a walk in the park for us,” Gregory Bonadies said. “The sun’s not as intense here.”

“In Florida, we stay inside,” Simoni Bonadies said. “Here, you have a lot of walking outside, but we feel good.”

Visitors Tom and Sue Gorski, 72 and 71, are also used to the heat.

“We’re from Baltimore; we’re used to this stuff,” Sue Gorski said.

Luz Ramos, 39, and her 5-year-old twins, who perhaps had not heard about the land breeze, are going down the Shore to Saturday to escape their hot North Philly home.

“Today we are doing everything we have to do so we can spend the weekend at the beach,” Ramos said.

Those who spend their summers working outdoors — like muralists, musicians, and roofers — say taking measures like hydrating properly, shifting schedules, and wearing clothes made of natural and lightweight fabrics can help you stay comfortable in the heat.

Firefighter George Kronbar, left, of Northeast Philadelphia, and EMT Jermel Bowen, 34, of Mount Airy, Pa. cool off from the heat with cool wet towels after helping the elderly move out of an apartment building that partially lost power.
TYGER WILLIAMS / Staff Photographer
Firefighter George Kronbar, left, of Northeast Philadelphia, and EMT Jermel Bowen, 34, of Mount Airy, Pa. cool off from the heat with cool wet towels after helping the elderly move out of an apartment building that partially lost power.

In an ironic side note, while the region has been steaming for the past three days, we are not technically in a heat wave. The high at the airport hit 89 on Thursday, a degree short of the 90-plus needed for three consecutive days to qualify as a heat wave.

But not everyone is wishing the hot temperatures away.

South Philly native Blanca Rodriguez and her 10-year-old daughter, Diamante, love the heat — Rodriguez said the two like to enjoy it before winter comes, and plan to head to a neighborhood pool for the weekend.

“Summer’s not that long, especially here,” she said. “The triple digits actually make me happy."