Activity at Kilauea Volcano’s lava flow front remained "sluggish" Saturday, with more vigorous breakouts farther upslope, U.S. geologists reported.

A Civil Defense overflight Saturday morning found that while the flow front had not advanced, there was a small increase in activity along the flow edges compared with Friday morning.

The breakout along the north side of the existing flow had advanced by about 75 yards since Friday and was burning forest, according to the Hawaiian Volcano Observatory. That’s where the lava crosses a system of cracks about 3 miles upslope of the front.

The Puu Oo cone is fueling the so-called June 27th flow that is headed toward Pahoa and Highway 130.

The eruption in Kilauea’s middle East Rift Zone started with a fissure eruption on Jan. 3, 1983, and continued with few interruptions at Puu Oo or from vents within a few kilometers.

A fissure eruption on the upper east flank of Puu Oo on Sept. 21, 2011, fed the so-called Peace Day flow that advanced southeast through the abandoned Royal Gardens subdivision to the ocean within Hawaii Volcanoes National Park in early December 2011. The flows stalled and re-entered the ocean starting on Nov. 24, 2012, until activity started to decline and the ocean entry stopped in Aug. 20, 2013; the flow was dead by early November.

The Kahaualea flow, which started at the northeast edge of Puu Oo in mid-January 2013, was dead by late April 2013, but a new flow dubbed Kahaualea 2 became active in the same area in early May 2013. The Kahaualea 2 flow died following the onset of a new breakout from the northeast flank of Puu Oo on June 27.

The June 27th flow, which continues to advance toward the northeast, poses no immediate threat to residential areas but could reach Pahoa within weeks, scientists estimate.