DOWNTOWN — Chicago will be dangerously hot this weekend as a heat wave sweeps over the city.

It could feel as warm as 115 degrees at points, and the National Weather Service has issued an Excessive Heat Warning that starts noon Thursday and lasts until 7 p.m. Saturday. The warning notes “dangerously hot temperatures” are coming and the heat and humidity “will combine to create a dangerous situation in which heat illnesses are likely.”

While Thursday morning was expected to see some rain, the National Weather Service said the city would get warmer and more humid throughout the day with temperatures hitting up to 91 degrees near the lake. It will feel more like 101 degrees near the lake and could feel as warm as 110 degrees further west.

Friday and Saturday are likely to be the hottest days, though: They’re expected to be sunny and hit up to 100 degrees, though Friday could actually feel as hot as 115 degrees, according to the National Weather Service.

Today: Showers and storms will swing through the region this morning and into the early-afternoon. This will delay heating today as a result. The highest heat indices will be across our southwest with readings in the 105-110 degree range. #ILwx #INwx pic.twitter.com/BPPOLCB8Fb — NWS Chicago (@NWSChicago) July 18, 2019

RELATED: Hot Weather Is Finally Here, But Doctors Want You To Stay Safe During These 90-Degree Days

Sunday is expected to be much cooler and cloudier with a high of 79 degrees and a chance for thunderstorms.

Hoping to help, My Block, My Hood, My City is offering free fans and cold water to elderly people in the city who are in need during the heat wave. Those interested can fill out a form online to have the items dropped off at their home.

The National Weather Service warned people to drink fluids, stay in air-conditioned rooms, avoid and the sun and to check up on family and neighbors. The agency also said people should not leave children or pets in cars.

Those who have to work or spend time outside should take extra precautions, according to the National Weather Service. The agency advised Chicagoans to watch out for symptoms of heat exhaustion and heat stroke, to wear lightweight and loose-fitting clothing, to take breaks in shaded and cool areas and to reschedule “strenuous activities” so they occur during the early morning or night.

RELATED: South Side Cooling Centers Open As Heat Index Hits The 100s This Week

Earlier this summer, Dr. Jenny Lu, a physician with Cook County Health, said the most important thing people can do during the upcoming warm weather is to drink liquids throughout the day, not just when they feel thirsty. Those who are drinking caffeine and alcohol, which can make you dehydrated, should try to balance those fluids with water or other liquids.

People who have to be outside should also wear light, loose-fitting clothing, put on hats and avoid dark-colored clothes, Lu said. When outside, it can also help to wear sunscreen — don’t forget to get the back of your neck, ears and the top of your head if bald — and to take regular breaks to cool off.

If you are outside, watch out for signs of dehydration or overheating: headaches, dizziness, weakness, muscle cramps and really moist or cool skin. Those are all signs of heat exhaustion, Lu said, and if you feel them you should go somewhere to cool off “immediately.”

Symptoms of heat stroke, a life-threatening condition, also include being weak and confused, Lu said.

Cooling centers are open on the South Side and will have extended hours Thursday and Friday. Chicagoans can call 311 for information about the nearest cooling center or look online for a full list.

The heat will be the main story for the area into the weekend. The hottest days will be Friday and Saturday, with heat indices up to 115 degrees. Heat advisories and excessive heat warnings are in effect. pic.twitter.com/2CTLa6en0U — NWS Chicago (@NWSChicago) July 18, 2019

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