Extreme weather sets the stage for the season. It’s the time of snowy delights and endless night, but also for blizzards and howling wind. Love it or hate it, winter arrives every year, and not for the reasons you might think.

We investigate the intricate patterns of snowflakes, and grow some in the lab; uncover the best type of snow for snowballs; introduce the world’s largest snowman; meet the Winter Olympians who stay in tip-top shape even when temperatures are hot enough to melt snow; and the hibernating squirrels who may provide a key to the future of human organ transplantation.

Winter. If you can’t escape it, wrap yourself in some fascinating facts.