The heavy rains that swept into the Valley Thursday night added a good soaking to what is already one of the area’s wettest monsoons in recent years. With more than an inch of rain dropping in some places Thursday, the Valley has registered above-average rainfall for only the second time this decade.
Yet this doesn’t necessarily indicate it’s been an abnormally wet summer. This paradox gets to the heart of the monsoon, as seen Thursday when thunderstorms pounded Arizona- including the East Valley.
The downpour Thursday was the result of several storm systems from Yuma, Flagstaff, and Tucson converging over the Phoenix Metropolitan area, according to Jessica Nolte, a meteorologist with the National Weather Service in Phoenix. The rains were expected to continue until the early hours of the morning with a slight chance of storms on Friday, said Nolte.
Since June 15, Phoenix’s official gauge has recorded 3.35 inches of rain. In a typical monsoon season, which runs until Sept. 30, the total is 2.77 inches.
This is only the second year since 2000 the monsoon’s rain has come in above the climatological norm. In 2006, the total was 3.33 inches.
With weeks remaining in the season, more precipitation seems assured — but a weather expert warned against making a too-simple comparison against past dry monsoons.
“Trying to suggest all’s well everywhere is probably pushing it a little bit,” said Tony Haffer, meteorologist in charge of Phoenix’s National Weather Service office. “But it’s certainly an indicator” of a wet summer.
Heavy rain and wind Thursday forced an hour-long shutdown of flights at Sky Harbor International Airport, where winds reached speeds of 30-40 mph. The shutdown was lifted at 9:15 p.m.
The East Valley was hit with the heaviest downpours, according to the National Weather Service. Tempe registered 1.3 inches of rain at the Salt River and Priest Drive, and 1.1 inches at Arizona State University.
The heaviest rain reported in Mesa was 0.87 inches at Brown and Horne roads. In Chandler, 0.35 inches fell near Chandler Boulevard and McClintock Drive.
No major damage was reported as a result of the storms as of late Thursday, though flooding caused numerous street closures in Scottsdale.The heaviest rainfall in Scottsdale was at Highland Avenue and 68th Street with 1.26 inches.
This year, most of the monsoon’s activity has taken place in the East Valley, according to Haffer of the National Weather Service.
For official purposes, it is said to have rained here only if precipitation falls at a certain point: Phoenix Sky Harbor International Airport, where the weather service has its gauge. Otherwise, it doesn’t count, no matter if Scottsdale’s washes flood or a microburst blasts Mesa.
Storms this summer came close enough to the airport to register high rainfall totals.
For example, on July 13, torrential rain in central Tempe flooded highways and homes. About 4 miles to the northwest, the official gauge took in a daily record of 1.3 inches. And this past Tuesday night, a storm cell erupted over downtown Phoenix; the reading at the airport was 0.63 inches.
Those two storms produced almost 70 percent of this summer’s total precipitation, without counting totals from Thursday.“It’s difficult to say what that really means to the overall wetness of the monsoon,” Haffer said.
If a wet monsoon may not be all that wet, that might suggest a dry monsoon could’ve packed more rain than the numbers show. Then again, Haffer suggested even in the most parched of summers, the monsoon makes it rain somewhere.
“To be cynical about it,” Haffer said, “can you ever remember a summer when you didn’t see video of someone getting pulled out of a flooded wash?”