NYC under blackout threat amid heat wave

Energy provider Con Edison and Mayor Bill de Blasio have both sounded the alarm

New York City residents were being told to shut down appliances and scale back on air conditioning amid the threat of blackouts due to an ongoing heat wave in the Big Apple.

Energy provider Con Edison sounded the alarm on Wednesday by urging customers to conserve energy in order to "help keep service reliable," and followed up later with a tweet informing residents that they would be distributing dry ice to Brooklynites who had already lost power after four days of high temperatures and humidity. Roughly 1,700 people were impacted by the Brooklyn outages, FOX 5 reported.

Residents also received phone alerts calling for them to "immediately limit energy usage to prevent power outages as the intense heat continues," to "avoid the use of high-energy appliances such as washers, dryers, and microwaves" and to "limit unnecessary use of air conditioning."

Mayor Bill de Blasio then made a plea via Twitter, writing, "We need New Yorkers to take IMMEDIATE action: reduce your use of electricity in your home or your business for the rest of the day. We need to avoid energy disruptions during this heat emergency."

The mayor pointed to an alert from the National Weather Service in New York which stated that Wednesday saw record high (or tied) temperatures at LaGuardia Airport, in Newark, N.J. and Bridgeport, Conn.

Blackout threats for New York City are all too real for longtime residents. The city experienced a blackout in 2003 that shut down all of its 11,600 traffic signals and the entire subway system. New York was also sent reeling from a major blackout in 1977, that impacted nearly the entire city after lightning struck an electrical substation in Westchester County.