Map: Lake Fire explodes in Santa Barbara County mountains

Its western edge was within a mile of the former Michael Jackson Neverland Ranch, as well as several prominent wineries.

A wildfire burning in a rugged area of Santa Barbara County exploded to more than 12,000 acres in its first day.

The Lake Fire was reported around 4 p.m. Friday, July 5, near Zaca Lake, in the Los Padres National Forest. By about midnight, it had burned 4,673 acres, and at 1 p.m. Saturday it was at 12,227 acres (19 square miles), said the U.S. Forest Service’s fire management team.

It’s already California’s fifth-biggest fire of the season.

As of Saturday afternoon, no evacuations had been ordered in the sparsely populated area, but “prepare to go” warnings were issued for an area between Zaca Lake and Los Alamos.

Its western edge was within a mile of the former Michael Jackson Neverland Ranch, as well as several prominent wineries in the Foxen Canyon area.

The map above shows the approximate perimeter as a black line. For details of the evacuation warning and latest updates, see Santa Barbara County’s emergency map.

The fire’s cause is under investigation.

In 2007, the same area was burned by the Zaca Fire, which at that time was the second largest wildfire in California’s recorded history. It was started on July 4 by sparks from a grinding tool and wasn’t fully contained until Sept. 4; hot spots continued to burn until the last days of October. The final tally was 240,207 acres (375 square miles). Forty-three people were injured in the firefighting.