From sundown on the Winter solstice to sunrise on the 2nd of January you have 256 hours to create your game, art, tool, whatever around a theme of winter. 

For the Summer solstice I ran a small game Jam called GrowJam - the theme was gardening, growing, harvesting, farming and we had some great submissions that people really seemed to Enjoy so 6 months later here we are and its the Winter solstice so here is GrowJams sister jam. From longest night to the sun up on the first real day of the new year (because who wants a jam that ends 8am on a 1st of Jan, plus the 2nd made it last 256 hours) create anything you want around the idea of Winter, Frozen, Hibernation, Snow, Iceor even Longest Night itself.

This is an unranked jam so have some fun, be weird, be wonderful, be you.