How do people in Canada and the US predict the arrival of spring? A rodent called groundhog helps to do just that and there is even a day commemorating this called Groundhog Day. An interesting ritual happens on February 2 where people assemble to observe the groundhog. On this day, if the rodent comes out from its burrow and does not see its shadow because it is cloudy, it is said winter will soon end. If on the other hand, it is sunny and the groundhog sees its shadow, the small creature will supposedly retreat into its burrow, and winter will continue for six more weeks.