A Hailish Experience: What Just Happened Here?

Monday morning seemed like the perfect time to plant my new pyrus calleryana, or flowering pear tree. It wasn't. By the time I got home, its glossy leaves lay shredded on the ground, tiny victims of the hailstorm.  

As is often the case, the west side got the worst of it, with the largest hail stone, at 2 3/4 inches in diameter, landing near Lutheran Medical in Wheat Ridge. Skylights were destroyed, causing extensive flooding in homes, schools and businesses, cars were pummeled and rendered undriveable, and those who defied the "Mother's Day" rule about planting are now regretting their recklessness.

But what exactly is hail, why is it round, and why does it happen in the spring? 

A simple explanation can be found in Hail: Ice from the Sky, an article by Cynthia Light Brown for Ladybug Magazine, via DPL's Explora for Kids database. Basically, a hail stone begins as a tiny ice particle in a cloud and starts bouncing up and down during a windy thunderstorm, causing layers of ice to be added with every bounce. Finally, it becomes too heavy and plummets to earth, aiming itself at your car or tomato plant.  

The National Weather Service's Hail Awareness Page also has some fascinating facts:

  • A 2 3/4 inch hailstone is considered "baseball size."
  • The largest hailstone (nearly the size of a volleyball!) fell on July 23, 2010, in Vivian, SD, and had a diameter of 8 inches.
  • According to NOAA, the Kansas City hail storm on April 10, 2001, was the costliest hail storm in the U.S. and caused damages of an estimated $2 billion.

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Written by Lisa on May 10, 2017



Wow!  I would love to see those little pieces of ice bouncing through the clouds like yo-yos!!  That's so great - I had no idea!  

Concerned on May 11, 2017


Don't plant Callery Pear trees, they are an invasive species and they also smell abhorrent! (Some liken it to a particular male secretion)


Wow, Concerned, I did some research on the Cleveland Pear, and haven't seen such controversy since I Googled how to get rid of grape hyacinth.  Since I've already planted it, I'm hoping that this viewpoint from CSU will be somewhat accurate.  


Sure, some people might not like the scent of Callery Pears. However, the USDA does not list them as an invasive species in Colorado. Personally, I think they are beautiful trees.

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