PHOENIX — It’s official: August 2020 is going down as the hottest month ever in Phoenix, beating the previous record which was just set in July.
Summer 2020 is also officially the hottest summer on record for Phoenix.
The average temperature for the month of August reached 99.1 degrees. Previously, the hottest month on record was July 2020 with an average temperature of 98.9 degrees.
The average high temperature in August also topped 110 degrees for the first time ever, putting our average summer high temperature at 108.5 degrees.
Meteorologically speaking, the summer season runs from the beginning of June to the end of August.
Phoenix has also experienced a record number of days at 110 degrees or higher this year. That count stands at 50 days, which completely shatters the previous record of 33 days set back in 2011. We could still add more to this record tally, too.
Thirteen of those days reached temperatures of 115 degrees or higher, which is nearly double the previous record of seven days back in 1974.
It’s not just the days that have been hotter this year -- overnight lows have also set records. There have been 28 days with lows in the 90s this year, shattering the previous record of 15 days back in 2013.
Phoenix isn't the only spot in our state that set records last month. August was also the hottest on record for Flagstaff, Prescott, Payson, Winslow, and Page.
Tucson also experienced a record hot August with an average temperature of 92 degrees. It was also a record hot summer in Tucson, with an average summer temperature of 90 degrees.
Outside of Arizona, several areas across the southwest experienced an unusually hot summer.
The record-setting summer heat can be attributed to several key factors, including climate change. Temperatures across the southwest and here in Arizona have been warming for several decades. Four out of the top five hottest years on record for Phoenix happened within the last decade. Globally speaking, the last five years have been the hottest years on record.
Our summer weather pattern also played a role with an unusually strong ridge of high pressure that was often parked right over Arizona, bringing several long stretches of dangerously hot conditions.
The position of this area of high pressure also kept our monsoon moisture south of Arizona, limiting our monsoon storms and extending our wildfire season.
Our heat island has also played a role in keeping our overnight low temperatures significantly warmer.