We Love NYC: The Homecoming Concert kicked off on Saturday afternoon with a pre-recorded video featuring stars like Stephen Colbert. However, the concert ended early because of the approaching Hurricane Henri.
"Due to approaching severe weather, all those attending the event are to calmly move to the nearest exits and proceed to areas outside of the park. This is NOT an emergency", the New York City Police Department (NYPD) said on Twitter.
New York City Mayor Bill de Blasio said that people's safety was a priority.
"While it's disappointing that tonight's concert had to end early, the safety of everyone in attendance had to come first. To everyone who came out tonight: thank you. Thank you for showing the world that New York City is coming back stronger than ever before", de Blasio said on Twitter.
Earlier, the mayor declared a state of emergency in New York City. A tropical storm warning is also in effect citywide.
New York Governor Andrew Cuomo declared a state of emergency earlier on 21 August as Hurricane Henri threatens to make landfall in Long Island on 22 August. The storm is expected to affect coastal areas, as well as inland locations.