What is a heat dome? A meteorologist explains the weather phenomenon baking the northeast quarter of the US

A heat dome sent temperatures soaring as summer 2024 was about to begin. Orange is moderate heat risk for June 18, red is major, and purple is extreme. NOAA by William Gallus, Iowa State University Heat domes, like the one sending temperatures soaring from the Midwest to New England in June 2024, occur when a persistent region of high pressure traps heat over an area. A heat dome can linger for days to weeks, leaving the people, crops and animals below to suffer through stagnant, hot air that can feel like an oven. Typically, heat domes are tied to the behavior of the jet stream, a band of fast winds high in the atmosphere that generally runs west to east. Normally, the jet stream has a wavelike pattern, meandering north and then south and then north again. When these meanders in the jet stream become bigger, they move slower and can become stationary. That’s when heat domes can occur. Heat domes involve high-pressure areas that trap and heat up the air below. NOAA When the jet stream swings far to the north, air piles up and sinks. The air warms as it sinks, and the sinking air also keeps skies...