Nationally, heat-related mortality has risen by nearly 17 percent per year since 2016. As a result, New York City now issues heat alerts and opens cooling centers when the heat index is forecast to reach 95 degrees Fahrenheit or higher for at least two consecutive days or a heat index of 100 degrees Fahrenheit or higher for any length of time.

Nationally, heat-related mortality has risen by nearly 17 % per year since 2016. As a result, New York City now issues heat alerts and opens cooling centers when the heat index is forecast to reach 95 degrees Fahrenheit or higher for at least two consecutive days or a heat index of 100 degrees Fahrenheit or higher for any length of time.