"We need New Yorkers to take IMMEDIATE action," de Blasio tweeted Wednesday afternoon. "We need to avoid energy disruptions during this heat emergency. The extreme heat will hopefully break early tomorrow morning."
Con Edison has requested that customers conserve energy as well, reducing the use of non-essential electronic devices and appliances like clothes washers, dryers, dishwashers, and unneeded lighting as they make necessary electrical repairs.
There are still over 3,500 customers across the five boroughs who are without power, with a majority located in Brooklyn and Queens.
Dozens of local businesses were forced to close due to the outage, while residents sat outside their apartments to escape the sweltering heat
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A blistering heat wave has seen an "excessive heat" warning issued for the city, with temperatures expected to reach their highest point so far this year.
Cooling centers have been opened all across the city to help residents. To find the cooling center nearest to you, call 3-1-1 or visit NYC.gov/beattheheat.