Flash flooding hit Naples, Florida, Monday as more than 6.5 inches of rain fell in about 5 hours. It was the city's wettest day in over 29 years.

The rain created major traffic headaches. According to WINK News, flooding turned Interstate 75 and the heavily-traveled U.S. 41 into a nightmare. The Collier County Sheriff's Office said Hunter Boulevard was under 15 inches of water at one point.

Photos from social media shows cars stalled on highways and water reaching higher than tires. 

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The heaviest rain fell early. The National Weather Service said 3.94 inches were recorded at the Naples airport between 12:53 p.m. and 1:53 p.m. That one hour of rain alone made it the wettest August day on record in Naples, breaking the old record of 3.84 inches on Aug. 11, 1958.

The flash flood warning was canceled around 5:30, but more rain was possible through the evening. As of 9 p.m., Naples had received 6.71 inches of rain for the day, making it the city's wettest single day since July 23, 1985.