USGS MAUNA LOA AFTERNOON UPDATE FOR DAY 6

2:45 AM · Dec 4, 2022

USGS (4:32pm) - The Northeast Rift Zone eruption of Mauna Loa continues, with little change since this morning. One active fissure, fissure 3, is feeding a lava flow downslope. Fissure 3 is generating a lava flow traveling to the north toward the Daniel K. Inouye Highway (Saddle Road) that has reached relatively flatter ground and slowed down significantly over the past several days, as expected. As of 1 p.m. today, December 3, the flow front was about 2.4 mi (3.9 km) from the Daniel K. Inouye Highway (Saddle Road). During the past 24 hours, the lava flow advanced at an average rate of about 40 feet per hour (13 meters per hour). Though the advance rate has slowed over the past 24 hours, the lava flow remains active. Advance rates may be highly variable over the coming days and weeks. On the flat ground between Mauna Loa and Mauna Kea, lava flows advance more slowly, spread out, and inflate. Individual lobes may advance quickly, and then stall. Additional breakouts may occur if lava channels get blocked upslope. There are many variables at play and both the direction and timing of flow advances are expected to change over periods of hours to days, making it difficult to estimate when or if the flow will impact Daniel K. Inouye Highway. Volcanic gas plumes are lofting high and vertically into the atmosphere before being blown to the west at high altitude, generating vog in areas downwind. Vog information can be found at https://vog.ivhhn.org/. Pele's hair (strands of volcanic glass) fragments are being wafted great distances and have been reported as far the Mauna Kea Visitor Information Station. Sulfur dioxide (SO2) emission rates of approximately 180,000 tonnes per day (t/d) were measured on December 1, 2022. Tremor (a signal associated with subsurface fluid movement) continues in the location of the currently active fissures. This indicates that magma is still being supplied to the fissure, and activity is likely to continue as long as we see this signal. 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.