Wednesday, July 27, 2016

Lightning really does strike the same place twice

Like a giant lightning rod, the CN Tower in Toronto is struck 75 to 80 times each year. (blogTO Photo)
6:30 AM: Another warm and humid day is forecast for Montreal today, with a high of 28C (83F), along with scattered thunderstorms.

It is often said that lightning will not strike the same place twice. This is a rather important and life- threatening myth. Over the weekend, a picture of the Empire State Building in New York City being struck by lightning was circulating on social media. It got me thinking, how often does such a tall building get struck? The answer is 25 lightning strikes, on average, each year, up to as many as 100 times. The CN Tower in Toronto, being taller, is struck an incredible 75 to 80 times each year. A series of 52 grounding rods, running the length of the building and six metres below the surface, prevents the structure from being damaged. Each rod is 56cm thick. For the most part, the strikes are spread out over the thunderstorm season. However, on August 24, 2011, the CN Tower was struck 52 times in less than 90 minutes. So as you can very well see, lightning can and does strike the same location often.

This video-still of the Empire State Building being struck by lightning was taken by a tourist on July 23. (

Several weeks ago, I wrote about lightning safety so I won't go into that here. Simply put, there is no safe place outdoors. When thunder roars, go indoors. We are half-way through what has been a hot and humid summer across most of North America, with frequent thunderstorms. Lightning-strike data is rather difficult to come by in Canada, but the United States has already recorded 21 fatalities. Sadly, this puts them on a pace to achieving a much higher total than that of the last few years. Since 2008, the message had been getting out, with fatalities down from nearly 50 annually to under 30. Here in Canada, we average 10 fatalities a year, along with multiple injuries. The problem is a global concern. Just last month, within a few days, over 80 people were killed from lightning strikes during monsoon rains across India.

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