A large sinkhole opened up amid heavy downpours in the San Bernardino Mountains Thursday night, prompting officials to close Highway 18 in both directions near Crestline.

The closure extends from upper Waterman to Mormon Rock just below Highway 138, Caltrans tweeted shortly after 10:30 p.m.

The sinkhole opened up when a rockslide left a southbound portion of the highway unsupported.

Officials ultimately decided to close traffic in both directions until further notice.

Images from the scene show the highway’s guard rail leaning over along the section of missing road.

Officials did manage to stop traffic before anyone was injured.

Highway 18 provides access for residents and visitors heading to Crestline, Lake Arrowhead, Running Springs and Big Bear.

Highways 330 and 138 can be used as alternate routes into the area.

The mountain communities are expected to receive up to 6 inches of rain before the stormy weather moves out on Sunday.

Authorities are warning that driving conditions in the mountains could become even worse as we head toward the holiday weekend.

Snow in the higher elevations left about 25 vehicles trapped on Highway 38 Thursday.

Snow levels could fall as low as 3,000 feet by Sunday, according to the National Weather Service.

Drivers are reminded that chains are required to travel in the mountains during winter conditions.