The March 2021 North American blizzard was a record-breaking blizzard in the Rocky Mountains and a significant snowstorm in the Upper Midwest that occurred in mid-March of 2021. It brought Cheyenne, Wyoming their largest two-day snowfall on record, and Denver, Colorado their second-largest March snowfall on record. The storm originated from an extratropical cyclone in the northern Pacific Ocean in early March, arriving on the west coast of the United States by March 10. The storm moved into the Rocky Mountains on Saturday, March 13, dumping up to 2–3 feet (24–36 in) of snow in some areas. It was unofficially given the name Winter Storm Xylia.