A spokeswoman said: "We've already seen this week people being ignorant to the extreme dangers and going on to the beach.
Hazardous materials
"We are especially worried this weekend with warm temperatures and warm weather.
"But our message is clear - stay away.
"We have got crews near the site on exercises so if anything happens we are ready to help."
The county council also believes potentially hazardous materials could have been exposed at the site which backs on to part of a disused landfill site.
Old fridges and broken bottles have been landing on the beach because of the earth movement.
The council says that more slips on the cliff near Lyme Regis are possible.
The area is part of 95 miles (153 km) of Dorset and east Devon known as the Jurassic Coast, with rocks recording 185 million years of the earth's history.
It was England's first natural Unesco (United Nations Educational, Scientific and Cultural Organisation) World Heritage Site.