How we know when and where lightning strikes

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The story of how lightning was first detected goes back to 1976 at the University of Arizona in Tucson.

While doing research for Kennedy Space Center for protecting rockets from lightning, a few professors got an idea on how they could create an instrument that would almost instantly record the angle and time of a lightning stroke and send it to a processor which would calculate the position in real time.

“This came directly out of a research lab into operations and into a commercial success,” said meteorologist Ron Holle with Vaisala.

Fast forward to 2016, and there are more than 100 Vaisala lightning detection sensors throughout the United States alone. The Vaisala lightning detection network covers the globe with hundreds more.

“When lightning is detected at one of these sensors, it sends the angle and the time to the control center here in Tucson and we take these angles and these times -- the circles are the times -- and calculate back to the position,” he said. “It takes about 15 seconds for the lightning position to be calculated from the time it occurs until it shows up on your screen.”

There are four sensors in Arizona. They are located in Rio Rico, Yuma, central Arizona and Window Rock.

“These are spaced, not so much that anything important is going there, but it’s spaced so the network is uniformly covering the country with equal distance between the sensors,” Holle said.

In August 2005 in Mesa, there was a bolt so powerful it was detected by sensors in Canada!

“Soil from the yard was thrown against the side of a house a block away from where it hit,” he said. “We looked it up, it was about 720 kiloamps which is just about as strong as it could possibly get.”

The destruction of 13 homes was proof of the power.

“Safety is a big issue in Arizona. We have specific drops on the data in a number of mines in Arizona because of explosives,” he said. Power companies and airlines are among others keeping their eyes on the data.

About 75 percent of Arizona’s electrical storms erupt in July and August. Most of those strike between noon and early evening.

“We’re in the top ten in the number of people killed -- in Arizona -- in the United States,” Holle said. “It isn’t typically raining very hard when we have lightning here and so the perception is that it’s not that dangerous.”

About 2.5 million strokes are detected in Arizona every year. Every single bolt is capable of killing.

“There is nothing you can do outside of a substantial building or a fully-enclosed metal-top vehicle that can make you safe,” he said. “It doesn’t matter what you’re carrying, what you’re wearing, how you stand, where you stand -- all those things are mostly myths.”

It’s why every second, every location and every lightning bolt matters.

Vaisala even goes beyond lightning detection. The company is the designer and creator of numerous weather instruments, including weather stations, weather balloons and dropsondes.