The website FiveThirtyEight wanted to know which American city has the most unpredictable weather. So, as it tends to do, it created a model, crunched a bunch of numbers and came up with an answer: Rapid City, South Dakota.

That’s based on temperatures, precipitation and severe weather. As for Phoenix, perhaps not surprisingly, it was deemed to have some of the most predictable weather in the country — in fact, only LA, San Diego and Honolulu were more predictable.

The data are from 2014, but we still wanted to get a Valley meteorologist’s perspective on them, so we called on Ken Waters — he’s warning coordination meteorologist at the National Weather Service in Phoenix.