Abnormally warm weather in Montana has begun to rouse grizzly bears from hibernation, a bit earlier than normal.

"We have had our first confirmed sighting of a Grizzly bear for the season," said Yellowstone National Park Spokesman Al Nash. "On Monday we had somebody spot a grizzly bear in the central part of the park and that bear was eating on a bison carcass."

Nash says this is occurring weeks earlier than normal.

"This is a bit early, I've looked back at the past four or five years and usually we see bear emergence in early March. We've had many mild days and some record-breaking high temperatures in the park and that has contributed to bears beginning to leave the den a bit earlier than normal."

Those interested in seeing a grizzly will have an opportunity to do so for free this weekend. Park fees have been waived at all national Parks in honor of Presidents Day.