Hawaiian Volcano Update: Episode 38 & V3cam Destroyed, Kīlauea Summit Eruption - December 11, 2025
Following a 9.5-day pause, Kīlauea’s 38th episode of its ongoing summit eruption began on Saturday, December 6, at 8:45 AM with vigorous lava fountains lasting just over 12 hours. Precursory activity began 20 hours earlier with periodic overflows from the north vent, which became steady with continual action at 3:37 AM. A rare triple fountain was on display during the opening hour of the episode, from the south vent as well as two openings on the north vent, all reaching about 500 feet or 150 meters high. However, a massive surge of lava was evident on webcams bursting through the base of the south vent cone by 9:40 AM, after which the south vent fountain first grew in height up to 1200 feet or 370 meters, then became inclined as a result of some obstruction. The incredible amounts of lava still reached up to 1000 feet or 300 meters once inclined, but landed over 0.4 miles or 0.65 km away, destroying the USGS-HVO’s V3 live-stream camera as well as the S2 camera. By 11:50, the dual north vents stopped erupting, while the south vent endured for another 9 hours.
Satellite views show the thickest tephra accumulation to the southwest of the vent within the closed area of Hawaiʻi Volcanoes National Park, however the eruptive plume reached up to 20,000 feet or 6,000 meters above sea level, and blew to the east, dropping baseball-size pieces of reticulite east of the summit along the Chain of Craters Road. Since the end of episode 38, both vents continue their typical degassing, but Kona winds this week have increased their impact by blowing into residential communities to the northeast. Typical releases are 1,200 to 1,500 tonnes of SO2 per day, sometimes rising to 3,000 to 4,000 tonnes. Vog and tephra remain the most common hazards for island residents, and the usual precautions and preparations apply, especially for those with respiratory sensitivities – more information at https://vog.ivhhn.org/.
Episode 38 produced the second largest outpouring of lava over the year-long eruption, slightly less than episode 3, though that event took 8.5 days to accumulate that volume. Up to 60% of Halemaʻumaʻu crater floor was covered by lava flows, which did not quite reach the eastern edge of the crater. This was the result of the fourth highest rate of lava output behind episodes 34 through 36, when both vents erupted continually throughout the episode, while during 38 activity focused solely on the south vent.
Following the most recent event, monitoring signals have again returned to the typical magma recharge pattern, suggesting another episode is likely within the forecast window of December 20 to 30.” All eruptive activity has been confined to Kīlauea’s summit caldera within Hawaiʻi Volcanoes National Park, with no increased lava threat to people. There continue to be no significant changes on either of Kīlauea’s rift zones. As usual, we summarize the monitoring signals, imagery, and reports available courtesy of the USGS Hawaiian Volcano Observatory, annotating the presentation on screen as we go and discussing live viewer questions.
