Much of the US East Coast is expected to witness temperatures top 32 degrees Celsius until Wednesday, reports Xinhua news agency.
According to the local emergency management department, people have been are advised to stay in cool places as much as possible and drink plenty of water even if they do not feel thirsty.
Speaking of the heatwave, New York City Mayor Bill de Blasio said: "Please do not treat it as business as usual. Don't go outside any more than you have to, stay hydrated, check on your neighbours, family members."
Local residents could get a spray cap installed at a nearby hydrant by the local firefighters for free so as to get a sprinkle of water, according to the Department of Environmental Protection in New York City.
New York City's Department of Social Services issued a red alert on Tuesday requiring enhanced outreach efforts to help people access cooling centres.
The National Weather Service New York issued a heat advisory on Sunday for northeast New Jersey, New York City, the Lower Hudson Valley and parts of Connecticut and further expanded its heat advisories eastward to include southwest Suffolk County on Tuesday.
Meanwhile, record-breaking heatwaves are scorching the US West Coast, drawing rising concerns on climate change around the globe.