Thunder snow is when cold air hits warm water , which produces huge thunder clouds.
It's thunder and lightning but instead of rain, its snow. It also looks and sounds different, visibility is poor, so your less likely to see the lightning flash.
But when night you can see the lightning as it reflects off the snowflakes, it is quiet because the snow muffles the sound.
Cold air rises into colder air which produce clouds. The clouds join which makes lightning and rain in clouds freeze which makes snow.
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