How Long Will Heat Wave Last? Predictions for Temps Across U.S.

Several U.S. states and cities are currently facing a wave of extreme heat and in some areas, temperatures are expected to stay high for the coming week.

On Wednesday, the National Weather Service Weather Prediction Center announced that across 28 states, spanning from California to New Hampshire, "Excessive Heat Warnings and Heat Advisories are in effect."

"High temperatures into the 90s and 100s will increase the risk of heat-related illnesses," the Weather Prediction Center said.

Just last week, a number of countries in Europe faced a similar heat wave. In response to the heat wave in Europe, the United Kingdom Royal Air Force was forced to suspend some flights with the U.K. Ministry of Defense announcing, "During this period of extreme temperature flight safety remains the RAF's top priority, so aircraft are using alternative airfields in line with a long-established plan. This means there is no impact on RAF operations."

Heat Wave
While several states and cities are currently facing a wave of heat, temperatures are expected to remain high in numerous areas for the coming week. Above, a child plays in the sculpture Changing Spaces of Jeppe Hein at Rockefeller Center on July 20 in New York. John Smith/VIEWpress/Getty

While speaking with The Gothamist, James Tomasini, a meteorologist with the National Weather Service, said that the high temperatures in New York could continue through next week.

"You can expect hot and humid conditions," Tomasini told The Gothamist.

According to the National Weather Service, a heat wave is defined as "a period of abnormally hot weather generally lasting more than two days."

"Heat waves can occur with or without high humidity. They have potential to cover a large area, exposing a high number of people to hazardous heat," the National Weather Service said.

In New Jersey, the National Weather Service predicted that temperatures could remain in the triple digits through Sunday.

"An extended period of dangerously hot and humid conditions will continue through Sunday with high temperatures in the mid to upper 90s each day. There will not be much relief from the heat overnight with minimum temperatures in the mid to upper 70s each night," the National Weather Service in Mount Holly said.

In other parts of the country, high temperatures are expected to continue for the coming weeks.

The National Weather Service Climate Prediction Center issued an update last week that warned of high temperatures in parts of the central U.S.

"Temperatures are favored to range from the mid-90s to the mid-100s with heat index values ranging from 100 – 110 degrees," the update said. "Greatest odds for the highest temperatures and impacts are for the central and Southern Great Plains and Mississippi Valley."

The update also noted that the high temperatures could persist through July 28, but could also continue till the end of the current month.

Jonathan Porter, a chief meteorologist for AccuWeather, told Newsweek that "In regards to the heat wave that the Northeast and the I-95 corridor is experiencing, the heat wave is going to likely last through the weekend and into Monday in most locations.

"The heat in the Northeast is likely to peak on Sunday with many major cities challenging record highs for the date. We are forecasting the hottest day in 10 years in some places, including Philadelphia. The heat wave is likely to break on Monday as thunderstorms move through the region."

Porter also said that in regard to the heat wave in the Southern Plains, "there does not appear to be much of a break in the heat on the horizon or any significant opportunity for drought-busting rain.

"One potential way we could start to see an increased chance for thunderstorms and needed rain would be from the tropics with a ridge parked to the north, steering flow out of the east could eventually bring some tropical moisture into Texas at some point, though there are no such features on the horizon at this time.

"In general, though, it looks like the dry and hot weather will continue, as AccuWeather meteorologists have been accurately forecasting for months in advance."

On Thursday, the Climate Prediction Center issued a forecast for temperatures in August. The forecast showed that areas in Texas, Louisiana, Arkansas and Oklahoma are expected to have above-average temperatures for August. Other states such as New York, Connecticut, Kentucky, West Virginia, Indiana and Illinois are also expected to have above normal temperatures, but the likelihood is lower than the other states mentioned.

Update 7/22/2022, 9:03 a.m. ET: This story was updated with comment from Jonathan Porter of AccuWeather.