Dual lava fountains at Kīlauea cover 60-70% Halemaʻumaʻu crater floor during Episode 39

Episode 39 of the ongoing Halemaʻumaʻu eruption ended abruptly at 2:13 a.m. on Dec. 24, 2025 after 5.9 hours of continuous fountaining (the start time was revised from 8:10 p.m. to 8:20 p.m. on Dec. 23 based on tilt and tremor data).

Lava fountains from the south vent reached up to 1400 ft while north vent fountains were just under 1000 feet around 9:30 p.m. on Dec. 23, the Hawaiian Volcanoes Observatory reports.

The north vent stopped erupting at approximately 2 a.m. HST. The south vent stopped erupting at approximately 2:13 a.m., marking the end of the episode, according to the HVO.

Episode 39 produced an estimated 13 million cubic yards of lava. The combined average eruption rate was over 250 cubic yards per second from the dual fountains. Lava flows from the fountains covered about 60-70% of the floor of Halemaʻumaʻu crater, the HVO reports.

The end of the eruption was coincident with a rapid change from deflation to inflation at the summit and a decrease in seismic tremor intensity, according to HVO scientists.

Most episodes of Halemaʻumaʻu lava fountaining since the eruption started on Dec. 23, 2024, have continued for around a day or less and have been separated by pauses in eruptive activity lasting generally at least several days. 

• Timeline of eruptive episodes since Dec. 23, 2024: https://www.usgs.gov/volcanoes/kilauea/science/eruption-information 
• Three Kīlauea summit livestream videos are available here: https://www.youtube.com/@usgs/streams 

No changes have been detected in the East Rift Zone or Southwest Rift Zone. 

Kīlauea Volcano Alert Level/Aviation Color Code remain at WATCH/ORANGE. All current and recent activity is within Hawaiʻi Volcanoes National Park.

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Episode 39 of the ongoing Halemaʻumaʻu eruption began at 8:10 p.m. HST on Dec. 23, according to an update from the Hawaiian Volcano Observatory. Sustained lava fountains approximately 100 feet in height are currently erupting from both north and south vents, with increasing heights.

Past episodes have produced incandescent lava fountains over 1,000 feet high that produce eruptive plumes up to 20,000 feet above ground level.  According to the National Weather Service, winds are blowing from the northeast direction, which suggests that volcanic gas emissions and volcanic material may be distributed to the southwest. 

• All eruptive activity is confined to Halemaʻumaʻu crater within Hawaiʻi Volcanoes National Park; commercial airports in Hawai’i County (KOA and ITO) will not be affected by this activity.
• Three Kīlauea summit livestream videos that show eruptive lava fountains are available here: https://www.youtube.com/@usgs/streams
• KPcam and MKcam provide views of the plume height for aviation purposes

Episode 39 was preceded by overflows of degassed lava that began at approximately 6:41 p.m. from the south vent and continued to increase in intensity until 8:10 p.m., when sustained fountaining began, according to the HVO.

Most episodes of Halemaʻumaʻu lava fountaining since Dec. 23, 2024, have continued for around a day or less and have been separated by pauses in eruptive activity lasting generally at least several days. 

• Timeline of eruptive episodes since Dec. 23, 2024: https://www.usgs.gov/volcanoes/kilauea/science/eruption-information 

No changes have been detected in the East Rift Zone or Southwest Rift Zone. 

Kīlauea Volcano Alert Level/Aviation Color Code remain at WATCH/ORANGE. All current and recent activity is within Hawaiʻi Volcanoes National Park.