Phoenix, the heart of Arizona’s Sonoran Desert, is no stranger to scorching heat, but July stands out each year as the most unrelenting month when it comes to high temperatures. Historically, this is when Valley residents experience the most intense and prolonged heat waves, with average temperatures peaking at 93.5°F (34.2°C) from 1924 to 2024.
July 2023 set an unprecedented benchmark in Phoenix’s climatological history. With an average monthly temperature of 102.7°F (39.3°C), it became not just Phoenix’s hottest month on record, but also the hottest month ever recorded in any U.S. city. The relentless 31 consecutive days with highs exceeding 110°F (43.3°C) turned the city into a symbol of extreme summer weather.
July 2024 followed closely behind, ranking as the second hottest month in Phoenix history with an average of 101.1°F (38.4°C). That summer carved out its own legacy, as temperatures above 110°F were documented on 70 separate days, a record in itself.
August and June do bring intense heat, but they typically lag just slightly behind. August 2020, for instance, reached an average of 99.1°F (37.3°C), making it the hottest August on record. Meanwhile, June 2024 made headlines with a record-setting 97°F (36.1°C) average, beating the previous high from 2021.
Even though the Valley of the Sun is known for its long, dry, and sweltering summers, July consistently marks the peak of this seasonal furnace. With temperatures often exceeding 110°F, the urban heat island effect, limited rainfall, and persistent high-pressure ridges contribute to making mid-summer in Phoenix an extreme meteorological event each year.
As the National Weather Service continues to track rising averages and record-breaking stretches of heat, Phoenix residents are once again bracing for another blistering July in 2025.