On Thursday, a major monsoon storm smashed over metro Phoenix, bringing gusts of up to 65 mph, a wall of dust sweeping from the southeast, and an inch or more of rain in some spots.
According to the National Weather Service, total rainfall at Phoenix Sky Harbor International Airport was 0.24 inches, with Scottsdale reporting the greatest totals of 1.5 to 2 inches.
SRP reported power interruptions to roughly 22,500 customers, while a severe downburst damaged and uprooted trees in Ahwatukee. Sky Harbor reported severe winds, with a top speed of 65 mph at 4:30 p.m.
According to weather service meteorologist Gabriel Lojero, the storm formed above Sky Harbor and traveled to the northeast, dumping heavy rain in downtown Scottsdale.
“It was a very typical monsoon pattern setup,” Lojero stated. “We had the moisture and instability that encouraged thunderstorm development. The outflow came from the southwest, which helped to stimulate activity.”
Monsoon storms arise when there is moisture in the air, causing an airflow change and atmospheric instability.
Depending on where you were, the storm had varying impacts. Some locations had severe rain and high gusts, while others stayed largely dry.
Despite Thursday’s showers, this year’s monsoon is forecast to be drier than usual. Sky Harbor has received 0.74 of an inch of rain this season.
If the Phoenix region receives no further rain for the remainder of the season, it will be the eighth-driest monsoon on record.
Lojero anticipates dry conditions and temperatures that are typical for this time of year throughout the coming week.
“We’re going to go into a dry spell coming into the next several days,” Lojero said. “A drier than normal air mass is going to spread across the region, so we’re expecting thunderstorm chances likely through most of next week to remain under 10%.”
Thunderstorms are expected to be concentrated in Gila County’s higher terrain. The introduction of dry air into Phoenix reduces atmospheric instability, which enables storms to occur.
The heat will subside slightly over the weekend, but triple-digit temperatures are expected to persist until next week. “We’re forecasting highs right around 102 to 106 this weekend, which is right around normal,” he added. “As we head into next week, temperatures will slightly go up, but it looks like it’s going to stay below 110 degrees.”