Hottest Labor Day weekend ever (?) could set new records

The cooler temperatures of the last few days may be just a memory come Friday.

An excessive heat watch was upgraded to a warning on Wednesday by the National Weather Service for Friday morning through Monday night. Temperatures in the afternoon will range from 107 degrees to 115 degrees, with dangerously hot conditions possible throughout south central Arizona.

Forecasters said the Labor Day holiday weekend is shaping up to be the hottest ever on record for the region.

Forecasters warned of an increase of heat-related illnesses, including heat cramps, heat exhaustion, as well as heat stroke, which can be fatal.

The brutally hot temperatures this summer dropped Saturday and have been relatively lower in the days since. But the mercury will begin to climb Thursday (to about 106 degrees) and then to near or above 110 degrees through the weekend, according to the weather service.

It said record high temperatures for dates through the weekend are in jeopardy. Here are the record highs that are vulnerable: Sept. 4, 112 degrees in 2019; Sept. 5, 113 degrees in 1945; Sept. 6, 111 degrees in 2013 and Sept. 7, 111 degrees in 1979.

But the forecast seems likely to add at least a couple of days on to the record 50 days this calendar year with temperatures at or above 110 degrees. That record, which crushed the previous mark of 33 days set in 2011, was extended last Friday.

Friday, Saturday, Sunday and Monday will be sunny and hot with an east-southeast wind from 5 to 10 mph. There is little chance for precipitation through early next week.

The National Weather Service said Monday that August was officially the hottest month ever recorded in Phoenix with an average of 99.1 degrees, beating out the previous record of 98.9 degrees in July. Prior to Summer 2020, 98.3 degrees was the highest monthly average on record.

According to the weather service, the latest date that 110 degrees has been recorded in Phoenix was Sept. 19, in 2010.