The National Weather Service says 35,000 lightning flashes illuminated the Arizona sky Monday.
NWS Phoenix was able to track those flashes across Gila, Maricopa and Pinal counties.
In addition to the flashes, NWS says there were over 4,000 lightning strikes reported in Monday's storm.
The storm seemed to sneak up on Valley residents. It began with blowing dust around 6 p.m., and by 8 p.m., trees and power lines were down all over the Valley.
According to APS, 80,000 customers were without power at the height of the storm. SRP said it had about 41,000 customers out of power at the height of the storm.
Traffic signals and trees in the roadway kept several Phoenix intersections closed well into the morning.
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