Grounhog Day is a holiday celebrated in United States and Canada on February 2. In weather lore, if a groundhog, also known as a woodchuck, marmot, or ground squirrel, emerges from its burrow on this day and fails to see its shadow because the weather is cloudy, winter will soon end. If the groundhog sees its shadow, it will return into its burrow and winter will continue for 6 more weeks.Candlemas is sometimes the same day, and has similar beliefs about the coming weather.