Hottest States, Arizona Leads (2026)

1. NOAA 1991 to 2020 monthly climate normals · 1991-2020
2. NOAA 1991 to 2020 hourly climate normals

How we got this. The Heat Score is The Honest Local’s own recipe. Each source ranks every place on its own from 0 to 100 and the score is the average, so a place has to do well on all of them to lead. We don't score heat on the thermometer alone. We blend the July average high from NOAA's climate normals with the July average heat index at the same weather station, which folds in humidity so it reads the way the heat actually feels. Each source ranks every place against every other place that has it, and the average of the two ranks is the score that decides the list. The number we show you stays the plain July high, the figure people already know. A city uses the station nearest to it. For a state we never hand you one city's reading and call it the state's. We take its five largest cities, weight them by population, and run every source across all five. Each row says which cities and stations went into it. It refreshes when NOAA reissues its climate normals, about once a decade (the current set covers 1991 to 2020). For Arizona, that means population-weighted across Phoenix, Tucson, Mesa, Gilbert and Chandler (2024 Census population estimates), never one city standing in for the whole state; July mean max is each city's own nearest NCEI station reading, 1991-2020 normal.

Rankings by The Honest Local from public data, one page per list, refreshed on each source’s own cycle. Places with no reading are left out rather than estimated. Every value on this page carries its source in the page’s structured data.

Photos Shutterstock/F · Shutterstock.