Many across Southeast Texas trying to get a glimpse of the winter weather Monday witnessed a rare weather phenomenon -- thunder sleet!

12News StormTracker Chief Meteorologist  was out checking weather conditions when he caught the thunder sleet on camera. 

And he wasn't alone. 

12News got reports across the Golden Triangle about the thunder sleet. 

So what is it?

Thunder sleet is similar to thundersnow -- it's caused by an increase in elevated convective energy. All of this energy is called instability and is a lifting mechanism to produce lightning and thunder.

This is the same thing that happens during those spring and summer thunderstorms. But what makes thunder sleet (and snow) rare is that warm layer forms during cold weather events to create the rare sights and sounds!