A sweeping heat dome over the eastern United States pushed temperatures toward 40 °C and triggered widespread power outages. More than 150,000 households lost electricity, with New York alone reporting 27,000 outages. The surge forced utilities to cut voltage and urge consumers to conserve.

Wholesale spot prices leapt 240 % in New England and doubled in New York City, while the Midwest saw a 50 % rise. The spike reflects soaring demand for air‑conditioning amid a record‑high heatwave forecast through Independence Day.

Consolidated Edison slashed voltage by 8 % in parts of the Bronx and Manhattan, and Mayor Zohran Mamdani urged residents to set thermostats to 78 °F. Utilities also rolled out demand‑response programs, offering payments to customers who reduce usage during peak periods.

The crisis exposes a mismatch between growing electricity demand and the pace of new supply. Investors face higher operating costs, while consumers confront steeper bills amid already elevated fuel and food prices.