What The Hell Is A Groundhog?

Today is Groundhog day. Um, YAY?

Help me, how did this country start to believe that a groundhog (which by the way looks like a small ball of fur with eyes, and wicked teeth) could predict the weather for the next six weeks? I mean maybe tomorrow's weather, or even two weeks from now, but SIX weeks?! I'm sorry but it's not like we let cats predict earthquakes, or monkeys predict Hurricanes...So why do we let a groundhog...What in the hell IS a groundhog anyway, a giant rat?...Predict the next six weeks of weather?