In the Southwest (Arizona, Nevada, Sonora), summer brings extreme dry heat, often exceeding 110°F. This is also the time of the North American Monsoon , which brings sudden, violet afternoon downpours to the desert.

If spring is a battle, summer is an occupation. By June, the sun is brutal across the continent. The Southwest, from Arizona to California’s Central Valley, bakes under a "high-pressure dome," with Death Valley often exceeding 120°F (49°C). Conversely, the Southeast—from Houston to Atlanta—suffers under a different tyranny: humidity. The "dew point" becomes a local obsession, as the air grows thick enough to drink, and afternoon thunderstorms erupt daily like clockwork.

When people think of North America, the image of a white Christmas or a sweltering Fourth of July often comes to mind. However, describing the seasons across an entire continent is a complex task. North America is a vast landmass stretching from the Arctic Circle to the tropics, meaning the "four seasons" model applies differently depending on where you stand.

North America’s seasons are heavily influenced by two geographic factors:

Above the tree line, the concept of four seasons blurs.