On Sep 22, 2021, at 16:22, Ken Cameron via groups.io <rocks@...> wrote:

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Hi All,

Two weeks ago yesterday, September 7, we were hit by a supercell thunderstorm, the least common and potentially most severe type of thunderstorm (Wikipedia description below). I was sitting outside watching the lighting and took the attached photo about 7pm with my iPhone.? I would have taken a better, wider angle, photo with my camera, but I really didn’t understand what I was seeing. Nevertheless, the photo shows three parts of the supercell. Shortly after that photo was taken, we had pea-size hail and three-quarters of an inch of precipitation that came down at the rate of 4”/hour. Apparently they had quarter-size hail in Bisbee that broke skylights.

The next day I notice that the tall grass around the house was beat down in spots. A few days later Teresa and Mark told me that they noticed that a couple of our roof tiles were displaced. ?The roofer was here for repairs today, and he reattached eight tiles. He said the damage was caused by a microburst, which is a strong downburst of wind that commonly accompanies supercells.

So, you might want to check your roofs.

Ken

From Wikipedia: “A supercell is a thunderstorm characterized by the presence of a mesocyclone: a deep, persistently rotating updraft. For this reason, these storms are sometimes referred to as rotating thunderstorms. Of the four classifications of thunderstorms (supercell, squall line, multi-cell, and single-cell), supercells are the overall least common and have the potential to be the most severe. Supercells are often isolated from other thunderstorms, and can dominate the local weather up to 32 kilometres (20 mi) away. They tend to last 2–4 hours.”

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