Sweltering temperatures expected across U.S. next week as heat dome descends on Midwest, Great Plains

Stifling heat is forecast to spread across much of the continental U.S. next week, with areas like the Great Plains and Midwest set to see temperatures climb 10 to 15 degrees above average, according to the National Weather Service.

The expected heat and high humidity come shortly after a record heat wave brought triple-digit temperatures to Oregon, Washington state and British Columbia at the end of June and caused hundreds of heat-related deaths.

Next week’s temperatures will be the result of a heat dome, a strong high-pressure system of air that descends from the atmosphere, compresses and heats up near land, exacerbating already sweltering summer temperatures.

Heat domes tend to inhibit cloud formation — leading to a hot, sunny sky with no cloud cover — and will likely grow more severe as the climate changes. 

The heat wave in June, also the result of a heat dome, was estimated to be a once-in-a-millennium event made virtually impossible without human-caused climate change, researchers found.

The temperatures and drought conditions have also triggered more intense wildfires that ignited earlier than usual this year. In recent days, more than 80 wildfires have burned in over a dozen states, mostly in the West, which is in an unprecedented drought.

The smoke from the Western fires was so severe that it created haze-filled skies and unhealthy air quality as far away as New York, New Jersey and Pennsylvania this week.

The Earth has already heated up more than 1 degree Celsius compared with preindustrial levels, according to the World Meteorological Organization. Last year was the hottest on record, and 2021 is virtually certain to be among the 10 hottest years ever recorded.

Research shows that more than one-third of global heat-related deaths during warm seasons are attributed to climate change. And heat kills more people than any other weather disaster in the U.S.