A dangerous heat wave disrupts Fourth of July celebrations across the central and eastern United States, with many public events cancelled or postponed for safety reasons and power systems under strain. In Washington, D.C., the Great American State Fair on the National Mall temporarily closes as temperatures reach about 38°C, and the National Park Service’s Independence Day Parade is cancelled due to safety concerns. The Weather Service forecasts heat index values could reach as high as 115°F.
The extreme temperatures spread from the Midwest earlier in the week as a “heat dome” traps hot air and increases humidity. The heat strains electricity infrastructure: PJM, the power grid operator serving much of the Mid-Atlantic, South and Washington, D.C., orders customers in emergency conservation programs to reduce demand amid generator outages and overloaded transmission lines. In New York, Con Edison reports about 17,000 customers without power and urges additional conservation.
National weather authorities report over 185 million people are under heat alerts, with peak heat indexes approaching 46°C in parts of the country. Several cities cancel or adjust events, including parades in Philadelphia and Haddon Township, New Jersey, and a concert and fireworks in Watertown, New York, while Boston delays entry to a riverside fireworks event.
