• A daily rainfall record was set at the Phoenix airport.
  • Roadways were covered with water.
  • Stranded drivers had to be helped from their cars.

Seasonal monsoon rains dumped on parched parts of Arizona Friday, bringing flooding and prompting water rescues.

Flash flood warnings were issued in several areas as dry riverbeds filled with water and streets were covered.

A daily rainfall record was set at Phoenix Sky Harbor International Airport, where 0.44 inches had fallen by early afternoon, according to the National Weather Service.

Video posted to social media showed water running through streets in the Phoenix area.

People also had to be helped from stranded cars.

The National Weather Service in Tucson said the Santa Cruz and Rillito rivers, often a dry riverbed, filled with water, impacting roads, walkways and wildfire burn scar areas.

Drivers were advised to pay close attention to road conditions.

“After heavy rain, rivers can rage for hours, or even days,” the NWS said in a tweet.

Heavy rainfall and localized flash flooding caused the closure of several recreation areas including the Central and Northern Santa Catalina Mountains, Sabino Canyon and Pusch Ridge Wilderness.

There were several reports of intense lightning from storms on Thursday night. Earlier in the week, four people were struck by lightning at the Grand Canyon. Two were hospitalized.

The storms knocked down trees and power lines in some areas. About 17,000 homes and businesses were without power Friday afternoon, according to poweroutage.us, mostly in the Prescott area about 100 miles north of Phoenix.

Arizona’s monsoon season runs from June through September. By the middle of the monsoon, flash flooding becomes increasingly common as the dry washes are often flooded out and wet soils enhance runoff in new thunderstorms.

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The weather is expected to remain a threat through the weekend.

“Widespread showers and thunderstorms will erupt each afternoon this weekend with the help of a low pressure system moving through the Four Corners region,” weather.com meteorologist Jonathan Belles said Friday. “Flash flooding will continue to be a concern, especially in metro areas and in and around burn scars.”

The Weather Company’s primary journalistic mission is to report on breaking weather news, the environment and the importance of science to our lives. This story does not necessarily represent the position of our parent company, IBM.