Thundersnow – a thunderstorm that produces snow instead of rain – was reported Wednesday in several states, including portions of Maryland, West Virginia, Pennsylvania and Ohio from the sprawling winter storm that's lashing the eastern United States.
Convection — upward motion of air — helps produce thunderstorms. But it's fairly rare to have convection within a winter storm. Thunder and lightning are much more common in warm-season thunderstorms, according to meteorologist Jeff Haby.
When there's strong enough convection, along with plenty of moisture available, a winter storm can produce thundersnow.
During a winter storm, snowflakes and sleet pellets high in the clouds can collide, WUSA-TV said. Those collisions create the same static charges as in a summer thunderstorm. With enough static charge, lightning is created.
Thundersnow is typically associated with very heavy rates of snow, which can lead to reduced visibility. And while the snow sometimes muffles the thunder, the lightning can still be seen, said meteorologist Grant Gilmore of WFMY-TV in Greensboro, North Carolina.
One of the more well-known instances of thundersnow occurred in 2011 in Chicago, which involved Weather Channel meteorologist Jim Cantore. He's been on scene for several other "thundersnowstorms" since then.
Thundersnow is sometimes seen downstream of the Great Salt Lake and the Great Lakes during lake-effect snowstorms too, according to the National Severe Storms Laboratory.
Be careful out there: Thundersnow can be just as dangerous as a regular, rain-accompanied thunderstorm.
— Linda Nelson (@lnelson1466) February 20, 2019
This article originally appeared on USA TODAY: What is Thundersnow?: How a thunderstorm produces snow instead of rain