Heat-trapping high pressure systems can sit over an area for a week or longer

Dangerous heat is expected across large swaths of the U.S. this week, according to the National Weather Service.

Millions of Americans across the eastern half of the US are facing a prolonged stretch of dangerous and potentially record-breaking heat as Americans get set to head outdoors to…

Sweltering conditions are expected to last through the weekend

These unbearably hot and humid summer months are typically made possible by phenomena known as “heat domes.”

Meteorologist Ryan Maue described it as a "mega heat dome" ...

Sweltering conditions are expected to last through the weekend

Heat-trapping high pressure systems can sit over an area for a week or longer