The sun rises over the midtown Manhattan skyline, Chrysler Building, and Empire State Building on July 2, 2026, the day New York City was issued a heatwave warning. Viewed from Jersey City, New Jersey.
Gary Hershawn | Corbis News | Getty Images
A prolonged period of dangerous heat is expected to continue through the Fourth of July weekend in the central and eastern United States, putting enormous pressure on power markets and transportation systems.
High temperatures are expected to reach 105 degrees Fahrenheit (40.5 degrees Celsius), potentially setting daily, monthly and all-time highs, according to the National Weather Service.
This situation can pose an increased risk of heat-related illness, especially for vulnerable populations and those unable to provide adequate cooling, the NWS said.
The heat wave threatens to overwhelm the U.S. power grid and may force some people to cancel, postpone or change their plans for the busiest week of the year.
How the heat wave is straining the power grid
Wholesale spot electricity prices rose more than 243% in New England and more than 101% in New York City on Thursday, according to U.S. Energy Information Administration data. Electricity prices also rose nearly 55% in the Midwest and 45.6% in the Mid-Atlantic region.
The rise in electricity prices comes as demand for air conditioning soars, and the NWS warns that very high humidity will make heatwaves feel even hotter.
New York City Mayor Zoran Mamdani on Thursday called on residents to reduce the strain on the state’s energy grid, asking them to set air conditioners to 78 degrees Fahrenheit, turn off electronic devices when not in use and wait until early morning or late at night to run appliances like dishwashers and washing machines.
Mamdani also urged New Yorkers to stay indoors to avoid the worst of the heat and answered questions about Taylor Swift and Travis Kelce’s widely reported wedding planned at Madison Square Garden.
“My advice to all New Yorkers is to stay inside and stay cool. If you happen to be getting married at Madison Square Garden, stay inside and stay cool. I think this is a good example to set for the entire city,” Mamdani told reporters.
The heatwave comes as scientists warn that climate change is worsening the frequency and intensity of extreme weather events. The combustion of fossil fuels such as coal, oil, and gas is a major cause of the climate crisis.
Expect travel delays during the fourth week of July
Rail authorities have warned that delays are likely over the weekend.
Amtrak announced earlier this week that trains will have to operate at reduced speeds from 11 a.m. to 7 p.m. through July 4 and delays are possible due to extreme temperatures expected in the Northeast, Southeast and Midwest.
New Jersey Transit trains bound for New York were also expected to be delayed or canceled due to heat damage to equipment.
Commuters board the No. 4 train at Union Square Station in high temperatures on Thursday, July 2, 2026, in New York, USA. Power prices from New York to Virginia are soaring as sweltering heat threatens to overwhelm the U.S. power grid and disrupt travel for the Fourth of July holiday.
Bloomberg | Bloomberg | Getty Images
delta airlinesMeanwhile, the airline issued a service notice earlier this week saying it was waiving change fees for travel through New York’s LaGuardia Airport due to the extreme heat.
The Illinois Department of Transportation warned drivers to be on the lookout for damaged pavement, saying extreme heat can cause pavement surfaces to buckle.
