It was rude awakening this morning after officials found a 3-foot wide boulder on Campus Drive.
Shortly after that, the University sent out alerts that access to part of Campus Drive and some parking would be closed on the east side of campus near the mountain.
“It's not very typical of what goes on here," said UM Interim Chief of Police Marty Ludemann.
The reason for the rock fall is the melting snow combined with rain that we've seen in the last week.
"We're just concerned that pieces like that could come down on cars that usually park along there, and we're just concerned with property damage to cars and injury to people,” said Ludemann.
We wondered whether Mount Sentinel could have a rock slide.
“The risk is low, but of course the risk is not zero," said geosciences associate professor Andrew Wilcox.
Wilcox says that the fall was expected, but it's not typical near the university. He talked with staff members and none of them can remember the last time this has happened.
He says you can really tell if a rock slide will happen with how steep the slope is, how moist it is and by the way the slope looks -- is it convergent or is it divergent?
"For this hill slope, it's divergent. It's a pretty good indicator that it's fairly stable,” said Wilcox.
But some students say they're still concerned.
"As a student I thought, well maybe we should carpool today with my roommates of course or have someone drop us off whose not attending the university," said University of Montana student Patrick Hutton.
"There's no concern in my mind," said University of Montana student Christopher Broback.
As geologists assess the situation, for now, it's a matter of being cautious around mountains like this.
The trail to the M and the parking next to Campus Drive are now open.