Fast-flowing lava from a nearby erupting volcano threatens to force residents in a Hawaiian town to evacuate their homes in its path.

Authorities told locals the Big Island of Hawaii on Saturday to prepare for potential evacuations in the next three to five days depending on the speed and direction of the molten rock.

The lava already crept over a county road in the early hours of Sunday morning on the edge of Pahoa, the largest town in the rural region of Puna. The lava flow was roughly 35 yards wide and traveling northeast at about 10 yards per hour. The flow was only about six-tenths of a mile from the town's main street, Pahoa Village Road.

Despite this near proximity, the flow's erratic advancements make it difficult to predict when or if it will reach the village road, according to Hawaiian Volcano Observatory geologist Matt Patrick.

The Kilauea volcano has been continuously erupting since 1983. However, most of the lava expelled from these eruptions in the past has flowed south, engulfing the Royal Garden and Kalapana residential areas before reaching the ocean. Two years ago, the flow began drifting to the northeast, directly in the path to Pahoa.

Officials contacted nearly 50 homes through door-to-door visits, alerting them to the lava's latest movements.

"This is all something we've been preparing for and hoping wouldn't have to happen," the director of civil defense for Hawaii County, Darryl Oliveira, said.

He added that the county will issue a mandatory evacuation if the lava flow begins advancing at a rapid rate that would make it difficult for people to move out of its way in short notice.

The burning asphalt from covered roads was generating smoke, but Oliveira said it was not a health risk as the wind dispersed the fumes to less populated areas.

Hawaii Gov. Neil Abercrombie asked for a presidential disaster declaration Friday to allow local and federal emergency crews to help.