Those with certain health conditions like heart disease, asthma, kidney disease and obesity may be at higher risk of becoming ill, health officials say. The Centers for Disease Control and Prevention says elderly people and anyone spending an extensive amount of time working outside is also at risk.
To prevent that, the city's Health Department says New Yorkers should be trying to keep cool as much as possible. This includes staying hydrated, using air conditioning, taking a dip in the pool or at the beach and taking frequent breaks.
The National Weather Service issued a heat advisory for New York City starting Thursday at 11 a.m. and ending Friday at 9 p.m.
Click here for a list of cooling centers across the city.