What was the temperature record broken in Phoenix on December 21?

Phoenix broke its December 21 daily heat record by reaching 81 degrees Fahrenheit.

Why is Arizona experiencing unusually high temperatures in December?

An anomalously strong high-pressure system over Arizona is causing the unseasonably warm weather.

When might cooler weather arrive in Arizona?

A shift to cooler readings and unsettled weather is potentially expected around Christmas.

Home / Weather / Phoenix Melts: December Record Shattered by Heat Wave

Phoenix Melts: December Record Shattered by Heat Wave

22 Dec

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Summary

Phoenix broke its December 21 daily heat record with an 81-degree high.
Unseasonably warm temperatures are affecting several Arizona cities.
A shift in weather with cooler temps and rain may arrive by Christmas.

Phoenix Melts: December Record Shattered by Heat Wave

Phoenix, Arizona, faced a significant departure from typical winter weather on Sunday, December 21, as the city's temperature soared to 81 degrees Fahrenheit, breaking the daily heat record. This event is part of an ongoing winter heat wave affecting numerous communities across Arizona, with nearby cities like Glendale and Yuma also experiencing unseasonably high readings.

The National Weather Service confirmed that the 81-degree temperature at Sky Harbor International Airport surpassed the previous record of 79 degrees, which was set in 2024. Earlier in December, Phoenix had already tied a daily record with an 81-degree reading on December 15, a mark that had stood since 1942. Meteorologists explain this persistent warmth is due to an anomalously strong high-pressure system.