The celebrated groundhog known as Punxsutawney Phil emerged from his Pennsylvania burrow and saw his shadow, meaning another six weeks of winter, according to folklore.
Thousands of people gathered at dawn in Punxsutawney, a small town northeast of Pittsburgh, to celebrate Groundhog Day and watch Phil make his way out of his tree stump to offer his annual weather forecast.
However, scientists have cast doubt on the reliability of America's most celebrated rodent forecaster.
Pennsylvania's tradition of using a large rodent to predict the seasons dates back to the Pennsylvania Dutch belief that if a groundhog left its burrow and saw its shadow, it would scurry back inside and winter would go on for six more weeks.
However, professional forecasters warned ahead of Phil's forecast that his prediction is likely to be way off the mark.
The US National Oceanic and Atmospheric Administration has concluded that only 35% of Phil's forecasts have proved to be accurate, placing him at a lowly 17th compared to other rodent forecasters.
Staten Island Chuck, a New York-based groundhog, tops the rankings with an impressive 85% accuracy rate on his forecasts.
Phil and his predecessors, also called Phil, have been forecasting since 1887.
