PHOENIX -- Wind speeds were as high as 90 mph when a microburst hit Ahwatukee during a monsoon storm Monday, the National Weather Service said.
While NWS did not have an exact measurement, it estimated the wind speed by the size of trees that were uprooted and the damage that was caused. Some trees that were knocked over were more than one foot in diameter.
The wind was so severe in the Ahwatukee area of southeast Phoenix that it knocked down the scoreboard at Desert Vista High School's football field.
The Doppler Radar clocked wind speeds as high as 60 mph.
KTAR's Bruce St. James said a semitruck was blown over on Interstate 10 and there was nearly zero visibility on I-10 near Pecos Road and that some freeway signs were down.
The microburst happened just before 5 p.m. as severe weather was rolling into the Phoenix suburb. It affected an area about three miles in diameter.