By Suzanne Monaghan

PHILADELPHIA (CBS) — Wednesday is the first day of summer and the first day of what’s expected to be three days of temperatures above 90-degrees.

Preparation is key when it comes to coping with the heat. Sharon Congleton is an RN consultant with Philadelphia Corporation for Aging. She says have water on hand, plan to stay indoors and, if you don’t have air conditioning, arrange to go somewhere that does.

“If Philadelphia experiences a heat warning situation, senior centers throughout the city go on extended hours in order to provide cooling places for our older adults,” Congleton explained.

READ: Excessive Heat Warning Issued For June 20 – 22

The quick rise in temperature can be especially hazardous, according to Congleton.

“The body is almost sent into a shock mode, because temperatures have been very comfortable and then the way that the temperatures are supposed to climb is going to be a real shock to all of our systems.”

She says if you don’t have air conditioning, keep your windows open.

“Worst thing they could do (is close the windows) because that’s going to make the area they are occupying just like an oven, because there is no circulating air.”

People who experience heat stroke often don’t realize it’s happening. That’s part of why Congleton says it’s crucial to check on the elderly.

“They can become very confused, almost to the point of becoming giddy, combative so they don’t realize that they’ve had a change in their mental status because of being dehydrated and or being exposed to high temperatures for a long period of time.”

Jim Garrow with the Philadelphia Department of Public Health says they are preparing to activate their Heatline and are setting up cooling centers.

“We also have inspectors that will go out and conduct inspections at some of the group homes or the personal care boarding home to make sure they are complying with regulations about cooling during heat events.”

He says the elderly should have the number for the Heatline handy.

“Elderly folks can call into (the Heatline) and ask for help about where they can go to cool off or tips that they can undertake to make sure they stay cool in the heat.

That number is 215-765-9040 and is activated when there is a heat warning.

Top Content On CBSPhilly