What is the climate at Phoenix, Arizona?

One way to get a sense of a location’s climate is by reviewing its latest 30-year climatological period. For the United States, the National Centers for Environmental Information (NCEI) gives the official U.S. climate normals for numerous cities and weather observation sites across the country. Climate normals are updated every 10 years with the latest 30-year period being 1991-2020. Because short-term weather can vary greatly from one year to the next, it is useful to review the longer-term climate record for understanding the typical weather one might expect for a location. In other words, the term climate can be thought of as the collection of recorded daily weather conditions averaged over a period of time.

The Phoenix area is classified as “desert climate/low latitude hot” or “BWh” on the Koppen-Geiger climate classification system. The world climate classification is fascinating and worth its own explainer! Back to Phoenix for now. The Phoenix climograph for average monthly temperature and precipitation show an overall arid climate with annual precipitation only around 7 inches. Also, note there are two rainy seasons. One being the summer monsoon and the other spread more or less uniformly over the winter and early spring months. Temperatures tend to be mild in the cooler seasons, but quickly become quite hot by the start of summer in June, while not cooling off until late in the autumn season. Monsoon rains into September can bring temporary relief at times, though!

The following are daily records for Phoenix highlighting notable daily weather extremes: Max temperature (122°F - June 26, 1990), min temperature (17°F – January 5, 1950), max precipitation (3.30 inches – September 8, 2014), and max snowfall (yes, snowfall!) (0.40 inches – February 2, 1939).

So, in summary Phoenix, Arizona, really can see a variety of interesting weather including extreme temperatures, extreme precipitation, and that rare snowfall. Not only that, but also weather hazards to be aware of living in Phoenix range from severe thunderstorm winds, flash flooding, hail, blowing dust, lighting, and even an occasional tornado, when atmospheric conditions are just right!

Data Source: National Centers for Environmental Information