WSAZ - Blogs - Ask Josh

Ask Josh: Thunder Snow

Meteorologist Josh Fitzpatrick has all the details on a rare weather phenomenon known as thunder snow.

I just received a letter in the mail from one of my youngest viewers in the area.  Robbie, a second grader in Apple Grove, WV who asks: "Is it true that we can have lightning and thunder when it snows?  I have heard that it can but not very often."

Robbie, you're correct and thank you for your letter and for watching!

The answer is yes, it can lightning and thunder during a snowstorm.  We call it thunder snow and it's a rare weather phenomenon for this area.  I've only experienced it twice.  The first time I heard thunder snow was when I was ten years old in Gallia County, OH during the great blizzard of 1993.  It was that event that got me hooked on meteorology.  The second time I've ever heard it was during the blizzard of 1996. 

Here's how it happens...

Most regular thunderstorms are summer events in which warm, moist air in the lower atmosphere has very cold air over it.  In this unstable air mass, upward moving air, or updrafts of air create thunderstorms.

The turbulence crated by such a storm somehow establishes a separation of positive and negative electrical charges and when a lightning bolt tries to even out the difference, there is a clap of thunder.  Thunder is the sound generated when the lightning bolt heats the atmosphere near it very rapidly to a temperature higher than the sun's surface.  The fast expansion of the air creates a sonic boom and that boom sound is what we call thunder.

But the vertical division of temperatures and the high moisture at lower levels that typically lead to storms with thunder and lightning are rare in winter.  Only in the most powerful winter storms is there such an immense pool of very cold air above warmer, moister air at ground level.

A storm with thunder and lightning with snow is more likely to occur near the Northeast coast of the U.S. because the storm can form over the comparatively warm water of the ocean and move inland, meeting much colder conditions.

Lake effect snow from the Great Lakes commonly produce thunder snow as well.  I'll touch on lake effect snow in the near future.

If you have a weather related question that you'd like me to answer, put it in a comment.  Leave you're name and e-mail address, please and where you're from.

Thanks for reading!

Read More Blogs
powered by Disqus