🌵 Phoenix Weather

Life in the Valley of the Sun

Phoenix sprawls across the floor of the Sonoran Desert, ringed by mountains that trap heat and block storms, and it ranks among the hottest major cities on Earth. The defining number here isn't a single temperature but a tally: Phoenix averages well over 100 days a year above 100°F (38°C), and in the record-shattering summer of 2023 the city endured 31 consecutive days at or above 110°F (43°C). The all-time high stands at 122°F (50°C), set in June 1990 — hot enough that day to ground flights, because aircraft performance charts didn't go that high.

What "dry heat" actually means

You'll hear the phrase constantly, and there's truth to it: with humidity often below 15%, sweat evaporates instantly and 105°F (41°C) in Phoenix can feel more bearable than 95°F (35°C) in a humid Southern city. But "dry heat" is also dangerous precisely because it's deceptive — your body loses water faster than you notice, and dehydration sneaks up on people. UV levels are among the most extreme in the nation, and pavement can reach skin-burning temperatures. Locals adapt by living early: hiking, errands, and exercise happen at dawn, and the day's life shifts indoors by midafternoon.

Monsoon: the desert's second act

From roughly July through September, the wind shifts and pulls humid air up from the Gulf of California and Mexico, kicking off the North American Monsoon. Afternoons that began clear can erupt into violent thunderstorms, and the desert serves up its most spectacular weather: walls of dust called haboobs — some a mile high — that swallow the skyline in minutes, microbursts that flip planes and topple trees, and flash floods that turn dry washes into torrents. Arizona's "Stupid Motorist Law" exists specifically because drivers underestimate these floods.

Winter is the payoff

The reward for surviving summer arrives around November. From December through February, Phoenix is close to perfect: sunny days with highs in the upper 60s to low 70s°F (19–22°C), cool nights, and almost no rain. This is when snowbirds, spring-training baseball, and golf tourism flood the Valley. With roughly 300 sunny days a year and only about 8 inches (200 mm) of annual rainfall, Phoenix offers some of the most reliable winter weather in the country — the exact opposite of its summer reputation.