Heat Dome Grips Central US, Putting Millions at Risk

WASHINGTON- A powerful heat dome is expected to intensify across much of the central United States through the weekend and into next week, exposing around 70 million people to dangerous temperatures and widespread heat advisories, according to US weather forecasters.

The prolonged spell of extreme heat will push daytime temperatures above 100 degrees Fahrenheit (37.8 degrees Celsius) across a broad swathe of the country, stretching from Dallas to North Dakota. Forecasters warned that high humidity and unusually warm overnight temperatures will prevent adequate cooling, increasing the risk of heat-related illnesses.

The National Weather Service said the heat is being driven by a heat dome, an atmospheric pattern that traps hot air over a region for an extended period. Meteorologists warned that the system is expected to remain largely stationary during the coming week, allowing dangerous conditions to persist across the central United States.

“It looks like it is going to be pretty much stationary in that position as we go through the week,” National Weather Service meteorologist Bob Oravec said.

The affected region extends from the desert Southwest and Gulf Coast through the Great Plains and into parts of the Midwest. Temperatures in many areas are forecast to run between 10 and 15 degrees Fahrenheit (5.6 to 8.3 degrees Celsius) above seasonal averages, with some locations around Denver expected to challenge daily temperature records.

Western Nebraska was placed under an extreme heat warning, with temperatures forecast to reach as high as 108 degrees Fahrenheit (42 degrees Celsius) over the weekend. The heat is also expected to spread into typically cooler parts of Montana and Wyoming, where temperatures are forecast to exceed 100 degrees Fahrenheit (37 degrees Celsius).

Officials warned that persistently warm nights will increase health risks because the human body has little opportunity to recover from daytime heat. Children, older adults and people with underlying medical conditions remain particularly vulnerable to heat exhaustion and heat stroke.

Authorities across affected states have urged residents to stay hydrated, limit outdoor activity during the hottest parts of the day and seek air-conditioned spaces or designated cooling centres where available.

Communities are also implementing measures to reduce the impact of the heat. Organisers of Sunday’s Brickyard 400 at the Indianapolis Motor Speedway planned to provide water refill stations and shaded cooling areas for spectators, while recreation centres in Denver were set to offer air-conditioned refuge from the extreme temperatures.

Forecasters said some relief could reach parts of the central United States toward next weekend, although they cautioned that any moderation in temperatures may prove temporary. By the middle of next week, the most severe heat is expected to shift toward Texas and parts of the Gulf Coast.

Not all parts of the country will experience the extreme conditions. The National Weather Service expects much of the Mid-Atlantic, the Northeast and large areas of the Pacific Northwest to avoid the most dangerous heat during the current weather pattern.

The latest heat wave follows several periods of extreme weather earlier this summer. Parts of the eastern United States experienced unusually high temperatures in early July that disrupted Independence Day celebrations, while another period of intense heat affected the Southwest and Great Plains later in the month.

Scientists continue to caution that while it is difficult to attribute individual weather events solely to climate change in real time, rising greenhouse gas concentrations are increasing the likelihood of more frequent and more intense heat waves.

Andy Pershing, chief programme officer at Climate Central, said current conditions are consistent with long-standing climate projections that anticipated hotter temperatures, higher humidity and warmer nights as global carbon dioxide levels continue to rise.