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.
“You get the bang and the rumble but instead of it being dominated by rain and hail, it’s all snow that’s coming out of the system,” said Bureau of Meteorology forecaster Mick Logan.
When there’s strong enough convection, along with plenty of moisture available, a winter storm can produce thundersnow.
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.
— Canberra Times (@canberratimes) July 12, 2015
One of the more well-known instances of thundersnow occurred in 2011 in Chicago, which involved Weather Channel meteorologist Jim Cantore:
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.