CHICAGO (WLS) — Extreme heat blanketed the Chicago area starting Wednesday, with heat index readings expected to be over 100.

As the sun went down Wednesday, people got a little bit of relief as they strolled along the river walk downtown, but the weather threat is not over yet.

The National Weather Service has issued a Heat Advisory, which went into effect for the Chicago area at 10 a.m. Wednesday and will remain in effect until 10 p.m. Thursday.

As people were out enjoying the summer weather, city and health officials want to make sure that people stayed safe as well.

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The high temperature for Wednesday was expected to be 95 degrees, with heat index values of 100 to 110 degrees.

“People don’t realize how thirsty they are and once you start feeling thirsty, you’re already dehydrated,” Dr. Oyinkansola Okubanjo with Advocate Health said.

Dr. Okubanjo said people need to be listening to their bodies with the temperature soaring to dangerous levels. Top of mind is the possibility of heat stroke.

“If you notice that that person is not making any sense, they are already in heat stroke because the biggest thing we see is what we call mental status changes, so they are mumbling, they are muttering,” Dr. Okubanjo said. “Sometimes they could even have seizures, that’s really bad. Stop and call 911.”

OEMC is working to keep people out and about safe in the heat with cooling centers across the city. Cooling centers open at 9 a.m. Wednesday and Thursday and close at 5 p.m. both days, except for the South Kedzie location, which is open until 8 p.m.

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People can also find relief from the heat in city libraries, police stations and park district buildings.

The best way to avoid heat related illness is to limit your time outdoors, stay out of the sun, and drinks lots of water and fluids to remain hydrated. People should also check on relatives and neighbors, especially if they are elderly.

As the city sizzled in the extreme heat, Michele Lewis was scooping up big business at her sno-ball stand. Arguably the most popular woman at 31st Street Beach Wednesday, Lewis said as the temperature rose, so did her profits.

“Business has been wonderful,” Lewis said. “I’m constantly having to run to get ice, been selling out so business is great during these days.”

Lewis said after snow cones, the second hottest item on her menu was bottled water. Staying hydrated and shaded, if outdoors, was key to enduring what felt like triple-degree heat.

The draw to water elsewhere in the city on Wednesday was also irresistible. Residents and tourists had a hard time keeping kids from getting wet downtown at the Crown Fountain and its water play area in between the glass blocks.

In Auburn Gresham, Saint Sabina Church was giving water away at Racine and 79th street.

Father Michael Pfleger wants folks to check on older neighbors as he recalled the heat wave of 1995, when hundreds of Chicagoans died.

“Check on each other, let them know we care,” Pfleger said. “We can bless you with some cold water to keep you hydrated, and let somebody know that we care, and tell them to care about somebody else.”

Water was just what Bobby Taylor needed. He had just finished mowing his sister’s lawn and he was done having to be outside.

“AC, that’s it, AC,” Taylor said. “I’m going to get out my clothes and jump in the shower and it’s over for me.”

Brenda Hayes is recovering from surgery and said the heat makes it harder for her.

“It’s taking a big toll on me,” Hayes said. “I am so hot it makes me so sick, all I can do is stay in the house.”

Emergency Room Dr. Michael Anderson at Advocate Healthcare urges Chicagoans to especially watch out for older residents.

“Elderly folks won’t notice one of the presenting issues can be confusion, and that interferes with decision making when we start to notice our home getting hotter,” Dr. Anderson said.

Some people could not avoid the heat on Daley Plaza Wednesday.

Vendors competed in the Taco Throw Down. No matter who won, they were all battling the heat and did their best to take care of themselves.

“Plenty of water, energy drinks,” food truck operator Victor Quiles said. “I don’t eat it. I eat… fruit, and water.”

Working inside a food truck, the temperatures quickly rise when they are busy making food.

“We learned this is not something to be played with, it is serious business out here,” said Veronica Linares, working at the LaCalaca Food Truck. “The weather can play a lot of tricks on you, you can get dehydrated, you can faint.”

The owners of La Calaca Food Truck said the temperature inside can 140 degrees.

“We all really focus on staying positive, checking each other out, if some one needs to step in making sure everyone is okay, and if they are not then we step in for them to step out for a little bit, and we all have our water bottles and we are ready to rock n’ roll,” Linares said.

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“Make sure I stock up on water,” said Daniella Williams, who was exercising on Lakefront Trail. “I’m usually am bad at that. So I’m like oh my gosh the other day I felt like I’m dying, but I just add electrolytes.”

Early Wednesday morning, runners and cyclists took to the lakefront trail to get in some exercise before conditions become unbearable.

“You definitely feel the heat and humidity already. I can feel it pooling up in my hat,” Patrick Burke-McCoy, exercising on the Lakefront Trail, said. “It’s definitely warmer this morning than in past mornings.”

Campers at the nearby Columbia Sailing School worked to keep cool on the water…as the sun beams down.

“We’re encouraging lots of hydration and sunscreen, frequent swim breaks before and after they go out on the water,” Mike McBrien with Columbia Sailing School said.

McBrien says they are limiting how much time these young sailors spend under the sun.

“Shorter sailing sessions, a little more swimming and then trying to keep the kids in the shade,” he said.

ComEd’s energy efficiency experts offered tips for those looking to escape rising temperatures while also keeping their monthly bills down, like closing shades and making sure air vents are not blocked.

“So that you get the airflow throughout your house that cools the space and makes it comfortable,” said Teri Lewand, Senior Manager of Energy Efficiency Portfolio ComEd. “The other thing you’re going to want to think about doing is setting your temperature up as much as you can that doesn’t create an uncomfortable house… Little changes, tweaks to how you operate your thermostat, really, can make a significant difference on your bill.”

ComEd said they also have programs offering incentives to bring down the cost of that energy bill, including installing heat pumps to better heat and cool homes. The utility company also has a relief fund for customers.

An AccuWeather Alert for the dangerous heat will continue on Thursday.

For those who can’t stay inside or their home is not sufficiently cooled, there areresources around Chicago to help.

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