The National Weather Service has issued a flood warning for south central Pima County in effect until 7:15 p.m.
Radar detected a cluster of thunderstorms near the U.S.-Mexico border that dropped between 2 and 3 inches of rain.
Though the Tucson metro area hasn't had a drop of rain, surrounding areas have had had scattered showers throughout the afternoon.
Rain has been reported in Marana and in areas west of Tucson including the Tohono O'odham Nation, according to the National Weather Service.
Tucson broke a heat record today, with a high of 107 degrees recorded at Tucson International Airport at 1:04 p.m. The previous high for this date was 106 degrees in 1987.
The temperature dropped down to 91 degrees a few hours later because of cloud cover from the storm.