Has anyone heard of a thundersnow? Well it exists, a thunderstorm in the middle of a snow shower!
This freak phenomena is one that may happen once a winter in a single location, and can only happen in certain areas throughout the country. The science behind this is explained well by the Weather Channel, but I am also going to break it down for you.
Normal snow storms clouds only reach up to about 20,000 feet into the atmosphere, not allowing them to have enough power or space to produce lightning within the clouds. However, this is different for things such as lake effect snow (snow storms from storms being pushed off of the great lakes that contain warmer air) or larger systems that turn into snow storms as they move north. With the warmer air stirring up the clouds, it creates almost a firing turret for the lightning to develop and grow within. These turrets rise to about 5,000 feet above the regular cloud base and the warmer air allows for the molecules to charge.
The charging of the molecules within those turrets is caused by both snow and small hailstones called grauple interacting. This interaction builds the charge up and with enough time and charge there is the possibility of lightning. This process is much like when you have static electricity from rubbing against conductive surfaces and then touching another surface unleashes the charge.
So next time you think you heard thunder in the winter but want to count that out, just reconsider and check the weather to see if the conditions are right!