A polar bear at Memphis Zoo joyfully rolls in fresh snow – not a common occurrence in Tennessee. ⁣ ⁣ The US has been blanketed by a monster winter storm that killed at least 18 people, grounding thousands of flights and leaving tens of millions digging out in bitter cold.⁣ ⁣ #PolarBear​ #WinterStorm​ #USWeather​ #Snowstorm​