Mauna Loa lava flows reach flat area, slows its approach to Saddle Road

Two active fissures; Flat land slows lava flows

The Northeast Rift Zone eruption of Mauna Loa continues, with two active fissures feeding lava flows downslope.

Fissure 3 remains the dominant source of the largest lava flow. The fissure 3 lava flows are traveling to the north toward the Daniel K. Inouye Highway (Saddle Road), but have reached relatively flatter ground and have slowed down significantly as expected, according to the lates Hawaiian Volcano Observatory update.

Advance of the largest flow slowed over the past 24 hours to a rate of 0.025 miles per hour (40 meters per hour). As of 7 a.m. HST Thursday, the flow front is about 3.4 miles from the Daniel K. Inouye Highway (Saddle Road). Advance rates may be highly variable over the coming days and weeks due to the way lava is emplaced on flat ground.

Fissure 4 is still active with lava flows moving toward the northeast at a rate of 0.04 miles per hour (60 meters per hour).  The northeast fissure 4 lava flow crossed the Mauna Loa Weather Observatory road overnight. A small lobe is moving to the east from fissure 4 at a slower rate than the main lobe. Volcanic gas plumes are lofting high and vertically into the atmosphere. Pele’s hair (strands of volcanic glass) is falling in the Humu‘ula Saddle area. 

Seismic monitoring detects tremor (high rates of earthquakes) in the location of the currently active fissures. “This indicates that magma is still being supplied, and activity is likely to continue as long as we see this signal,” according to the HVO.

There is no active lava within Moku’āweoweo caldera, and the Southwest Rift Zone is not erupting. “We do not expect any eruptive activity outside the Northeast Rift Zone. No property is at risk currently,” the HVO reports.

As flows reach flat land, lava will “spread out and inflate”

The Northeast Rift Zone eruption of Mauna Loa continues, with two active fissures feeding lava flows downslope, according to the latest update provided by the Hawaiian Volcano Observatory.

The fissure 3 lava flows are travelling to the north, still moving toward the Daniel K. Inouye Highway (Saddle Road). Fissure 3 remains the dominant source of the largest lava flow. Advance of the largest flow slowed between 7 a.m. and 12:30 p.m. HST Wednesday to a rate of 0.02 miles per hour (24 meters per hour). As of 12:30 HST p.m. Wednesday, the flow front remained about 3.6 miles (5.8 km) from the Daniel K. Inouye Highway (Saddle Road).  

“The flows are reaching a relatively flat area and are beginning to slow down; as this happens, the lava flow will spread out and inflate. Forecasts indicate it may take two days for lava flows to reach the Daniel K. Inouye Highway (Saddle Road),” according to the HVO.

Fissure 4 is still active with lava flows moving toward the northeast. A small lobe is moving to the east from fissure 4 at a slower rate than the main lobe. Volcanic gas plumes are lofting high and vertically into the atmosphere. Pele’s hair (strands of volcanic glass) is falling in the Humu‘ula Saddle area, according to the HVO.

Seismic monitoring detects tremor (high rates of earthquakes) in the location of the currently active fissures. “This indicates that magma is still being supplied, and activity is likely to continue as long as we see this signal,” the agency reports.

There is no active lava within Moku’āweoweo caldera, and the Southwest Rift Zone is not erupting. “We do not expect any eruptive activity outside the Northeast Rift Zone. No property is at risk currently,” according to the latest HVO report.