Lava from Kilauea Volcano is advancing toward homes "very slowly," about 150 yards overnight, Hawaii island civil defense officials said after a Friday morning overflight.

Gov. Neil Abercrombie, meanwhile, signed an emergency proclamation Friday in preparation for lava crossing Highway 130, which could isolate lower Puna communities from the rest of the island. The proclamation would allow officials to open abandoned roads as alternate routes. 

County officials said the surface lava flow continues in an east-northeast direction with little vegetation burning. Subsurface activity also continued, evidenced by steam plumes coming from underground cracks, they said late Friday morning.

While the surface lava flow does not pose an immediate threat to homes in the Kaohe Homesteads subdivision, Hawaiian Volcano Observatory scientists estimates the flow is 0.7 miles from the border of the subdivision and could reach the area within a week if it continues flowing in the underground crack system.

On Thursday, observatory scientists raised the eruption alert level from a watch to a warning and Hawaii County Mayor Billy Kenoi issued a state of an emergency.

No evacuation order has been issued, but Kenoi said residents should be ready to leave their homes if necessary.

Hawaiian Volcano Observatory Scientist-In-Charge Jim Kauahikaua said the surface flow’s advance could slow as the lava spreads out.

The Associated Press contributed to this report.

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