(BIVN) – Low-level lava activity has returned to the summit of Kīlauea, as the ongoing summit eruption continues within Hawaiʻi Volcanoes National Park.
Overnight, the south vent within Halemaʻumaʻu produced numerous lava flows. The activity continued into Friday morning and appears to be ongoing.
The summit area remains highly pressurized. Data from the USGS Hawaiian Volcano Observatory website shows continued inflation. Changes in eruptive activity or location within the summit region are possible, scientists say.
UPDATE – (1 p.m.) – From the USGS HVO update on Friday:
Summit Observations:
Multiple overflows from the south vent were observed through the night starting at 10:16 PM HST. There were 15 overflows that lasted less than 5 minutes and were small, advancing less than 100 feet (30 m) from the vent. Then at 5:10 a.m. HST, a high-volume overflow coated the entire area within 300 feet (100 m) of the vent with pahoehoe in 10 minutes. This was followed by the current south vent overflows which began and 5:56 a.m. HST and continue at this time. A small dome fountain within the vent has been feeding multiple channels of pahoehoe that cover the near vent area and extend near a half a mile (about a kilometer) from the vent. The volume of lava and the size of the dome fountain appear to wax and wane over time, but continues to feed vigorous overflow channels. Spatter from all three vents (north, south, and west) was also observed overnight, as well consistent glow and occasional flames.
Irregular tremor bursts gave way to more continuous tremor around 6 a.m. HST, about the same time the south vent became continuously active and drainback events stopped. Twenty-one earthquakes were recorded over the past day, mostly in the southern and eastern regions of the summit region of Kīlauea.
Summit tiltmeters have shown minor changes in tilt, with an overall slight inflationary trend since Wednesday. GPS stations on opposite sides of Halemaʻumaʻu (CRIM and UWEV) show a small increase in length since the end of September suggesting longer-term inflation of the summit magma reservoir.
During inter-episode pauses, the sulfur dioxide (SO2) emission rate from the summit typically varies between 1,000 and 5,000 tonnes per day. Plumes of volcanic gas are visible from the vents in day-time webcam views. Winds are currently forecast from the north-northeast through today.
Rift Zone Observations:
Rates of seismicity and ground deformation remain low in the East Rift Zone and Southwest Rift Zone. SO2 emissions from the East Rift Zone remain below the detection limit. No significant ground deformation was recorded in either rift zone.
Analysis:
Kīlauea had been erupting episodically between December 23, 2024, and August 25, 2026, from two vents (north and south) in Halema‘uma‘u at the summit. Lava fountaining episodes generally lasted for less than 12 hours and were separated by pauses of two or more weeks. Irregular patterns of ground deformation at Kīlauea summit since the most recent lava fountaining episode, number 54 on August 25, 2026, prevent forecast modeling for when the next fountaining episode can occur. Ground deformation patterns indicate the magma chamber beneath Halemaʻumaʻu is pressurized beyond the level typically seen before recent fountaining events. This pattern was disrupted by the dike intrusion on September 30-October 1 and since then summit tilt has increased slowly with interspersed periods of decreased or flat tilt. The vigorous overflows from the south vent this morning indicate that magma remains very near the surface in the established vent complex and continues to be able to generate smaller dome fountains. It is possible that another fountaining episode from the north-south vent complex could occur; however, intrusive activity underneath Kaluapele is also possible, or magma could exploit existing weak crack systems in the summit region to erupt passively (with little or no seismicity or deformation).
HVO continues to closely monitor Kīlauea and is in contact with Hawai‘i Volcanoes National Park and the Hawai‘i County Civil Defense Agency about eruptive hazards. Kīlauea volcano alert level and aviation color code remain at WATCH/ORANGE and conditions could change rapidly.
