thundersnow

Yesterday afternoon it was snowing AND thundering.  I learned this phenomenon is called thundersnow:

Thundersnow, also known as a winter thunderstorm or a thunder snowstorm, is a relatively rare kind of thunderstorm with snow falling as the primary precipitation instead of rain. It typically falls in regions of strong upward motion within the cold sector of an extratropical cyclone, where the precipitation consists of ice pellets rather than snow. Thermodynamically, it is not different from any other type of thunderstorms but the top of the cumulonimbus are usually quite low.

God of Thundersnow