Tucson’s high temperature is expected to hit 100 on Wednesday for the first time in 2020.
Though the first triple-digit day in Tucson usually happens in May, having 100-degree weather as early as April is not unheard of, said Jim Meyer, a meteorologist with the National Weather Service.
“We’ve had some cool months over the winter, but April is turning out to be above-average temperatures,” Meyer said. “So it is probably going to end up being one of the warmer Aprils we’ve seen.”
The average recorded first 100-degree day is May 25.
In the last 10 years, the first 100-degree day has mostly been in May, according to Star archives.
The earliest 100-degree day in the last 10 years and the last time Tucson got triple-digit temperatures in April was in 2012, on April 22.
“It looks like May is going to have plenty of 100-degree days in it,” Meyer said. “It looks like the pattern is on the warm side.”
Still, it’s hard to predict whether an earlier first 100-degree day will lead to a hotter-than-average summer, Meyer said.
“It’s almost like nature tries to make up for it and balance things out,” Meyer said. “If you start out early with your 100-degree days you do have a better chance of having more above-average number of 100-degree days, but I don’t know, a lot of times it just seems like somewhere along the lines it just balances back out again.”
Last year’s first triple-digit temperature came later than usual for Tucson, on June 9, and May 2019 was unseasonably cool and the second-wettest on record.
But after that first 100-degree day last year, the temperature hit or surpassed 100 degrees every day for the rest of that month, he said.
Phoenix had its first 100-degree day Sunday.
It’s more common for Phoenix to have triple-digit temperatures in late April, Meyer said.
The monsoon is on track to start in late June or early July, which is when monsoons usually start each year, Meyer said.
“We typically have hot Mays and Junes and that’s still expected to have a bunch more 100-degree days in there,” he said. “And then we’ll start to taper off as the moisture moves in from the south in probably early July.”
Meyer said people should be extra cautious if they plan to grill or make a campfire because it is peak fire season in Arizona.
“Even with less activity due to all the social-distancing stuff, we’re still keeping a close eye out for wildfire problems,” Meyer said.
