D-FW is getting blanketed with thunder sleet this morning. What is it?

The dull grayness of the sky over Dallas-Fort Worth stood in stark contrast to the white blanketing the ground as a winter storm brought below-freezing temperatures and thunder sleet to the region Tuesday morning.

How rare is thunder sleet, and does it consist of what its name suggests?

“Yeah, I suppose so,” said Hunter Reeves, a meteorologist with the National Weather Service in Fort Worth. Sleet is essentially small pellets of ice. When sleet mixes with conditions that would typically cause a thunderstorm — a tall, vertical system that produces thunder and lightening — those conditions can cause thunder sleet.

“Based on the data we’ve got, there’s a little bit of instability,” Reeves said. “Typically with showers they’re pretty low top. As far as the vertical extent, they don’t go too tall. But when you have instability they can grow vertically, and you can get lightning and thunder.”

The mix isn’t exactly a rare phenomenon in North Texas, Reeves explained. “It definitely happens with this kind of setup, with where we’re at and where we’re located.”

Sleet will be recorded in weather data as snow, Reeves said. The NWS didn’t immediately have data for sleet accumulation as of 9:30 Tuesday morning.

North Texas is under a winter storm warning through Thursday morning. The storm forced schools and businesses across the region to close Tuesday, created widespread driving hazards and canceled flights at local airports.