What to Know About the Rare Arizona Storm That Brought Hail and a Possible Tornado

A rare late-season storm swept through northern and central Arizona from Tuesday night into Thursday, dropping hail the size of golf balls, knocking down trees and prompting a tornado warning in one mountain community, according to ABC News and The Guardian. The National Weather Service said the heaviest threat for the Phoenix area now is rain and flash flooding.

Here are answers to the main questions about the storm.

What happened?

ABC News reported that severe thunderstorms moved across the state overnight Tuesday and into Wednesday, bringing damaging wind gusts and 2- to 3-inch (5- 7.6-centimeter) hail. The National Weather Service issued multiple warnings and urged people to seek shelter and stay away from windows. According to both outlets, the hail pummeled roofs, shattered windows and dented cars.

The Guardian reported that the storms continued early Thursday through central Arizona, with hail and wind damage possible, along with some flood watches and the chance of tornadoes.

Where was the damage worst?

The Guardian reported that a tornado warning was in effect Wednesday night as a storm passed over Heber-Overgaard in Navajo County, about 140 miles (225km) northeast of Phoenix. Residents posted photos and video of uprooted trees and crumpled structures. The county sheriff’s office said significant damage and minor injuries were reported. About 3,000 people live in the community.

Trees fell onto homes, and utility poles were knocked down in what The Guardian described as a possible tornado. Republican state Rep. Walt Blackman, whose district covers parts of the county, asked for a state of emergency declaration. He said in a statement that families were without power, property damage was significant and at least one injury had been reported.

The Overgaard Baptist church said on social media that the storm hit as members were finishing a prayer meeting. The church said it lost trees, signs, fences and a few windows, and that members were shaken but unhurt.

Elsewhere, strong winds toppled trees in Flagstaff and Mesa, some of which landed on walls and carports. A few dozen ponderosa pines more than 30 feet (9 meters) tall fell in the Coconino National Forest, northwest of Flagstaff, ABC News reported.

Why is this storm unusual?

Tornado watches were issued for multiple areas of the state, the first Arizona has seen since October 2010, ABC News reported. Ryan Bernhart, a National Weather Service meteorologist in Flagstaff, said warm, moist air moving north is fueling storms coming off the California coast, and that changing winds can make them spin, creating conditions for tornadoes.

Bernhart called the event “very unusual for this area at this time of the year.” He also noted that the downed pines were not small or weak trees, but strong ones that the wind had knocked over.

Why does it matter for people in Arizona?

The storm has already affected homes, vehicles and power service in parts of the state, according to the reports. Some families in Navajo County were left without electricity, and local officials have been assessing significant property damage. A state of emergency declaration, if approved, would be a formal step to help address that damage, though the sources do not say whether one has been granted.

For residents of the Phoenix area, the weather service says the focus is shifting. Mark O’Malley, a meteorologist at the National Weather Service office in Phoenix, said the greatest threat to the metro area is heavy rainfall and flash flooding Wednesday night and Thursday morning. The weather service had urged people to take shelter during the worst of the thunderstorms and to stay away from windows.

What happens next?

Storms capable of producing hail and wind damage were still moving through central Arizona early Thursday, with flood watches in place in some areas and the possibility of tornadoes, the weather service said. Residents in affected areas can expect continued updates and warnings from the National Weather Service as the system moves through the West. Blackman’s request for a state of emergency declaration is pending, according to his statement.

Around Prague, based on reporting by ABC News, The Guardian