USGS Volcano Notice - DOI-USGS-HVO-2025-12-07T00:34:25+00:00

HVO/USGS Volcanic Activity Notice

Volcano: Kilauea (VNUM #332010)

Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE

Issued: Saturday, December 6, 2025, 9:08 PM HST
Source: Hawaiian Volcano Observatory
Notice Number: 2025/H537
Location: N 19 deg 25 min W 155 deg 17 min
Elevation: 4091 ft (1247 m)
Area: Hawaii

Volcanic Activity Summary:

Episode 38 of the ongoing Halemaʻumaʻu eruption ended abruptly at 8:52 p.m. HST on December 6 after 12.1 hours of continuous lava fountaining.

The south vent stopped erupting at approximately 8:52 p.m. HST, marking the end of the episode. The dual north vents stopped erupting much earlier at approximately 11:50 a.m. Lava fountains reached heights of up to 1,000-1,200 ft (300-370 m) during episode 38. Fountains were down to about 400 feet (120 meters) high just before the abrupt end of the eruption. Lava fountaining lasted for 12.1 hours and produced an estimated 16 million cubic yards (12 million cubic meters) of lava. The combined average eruption rate was over 250 cubic yards per second (190 cubic meters per second) from the lava fountains.

Sustained lava fountains began erupting from two vents located within the north cone at 8:45 a.m. HST on December 6 after just over 5 hours of precursory lava overflows. The south vent then began fountaining at 8:49 a.m. By 9:15 a.m. a rare triple fountain event was underway with the two north vents and the south vent all erupting together at heights of about 500 feet (150 meters). By 9:40 a.m. the south vent fountain grew to about twice as high as the north vent fountains. The highest peak or instantaneous effusion rate of 1,300 cubic yards per second (1,000 cubic meters per second) occurred just before 10 a.m. when the south vent exploded. The enlarged south vent produced an inclined fountain over 1,000 feet (300 meters) tall that sprayed the south wall of Halemaʻumaʻu crater. Hot pumice and molten spatter from this fountain destroyed the HVO "V3" streaming camera site.

Lava flows from this episode's fountains covered 50-60% of the floor of Halemaʻumaʻu crater. Lava flows near the vents and on the floor of Halemaʻumaʻu within the southern part of Kaluapele (Kīlauea caldera) may continue to exhibit slow movement or incandescence as they cool and solidify over the coming days.

Volcanic gas emissions have greatly decreased with the end of the eruption. Earlier today the gas plume reached over 20,000 feet (6000 meters) above sea level. Tephra including Pele's hair and fine ash carried in lower levels of the plume fell in the town of Pahala and other communities southwest of the vents. Satellite imagery showed the upper regions of the gas and ash cloud moved due east of the summit across lower Puna and well out to sea before turning south. Reticulite pieces up to the size of a baseball fell along Chain of Craters Road east of Kīlaueaʻs summit transported by the high eastern plume. The extremely high effusion rates early in the eruption provided the gas and heat that drove this enormous plume.

The Uēkahuna tiltmeter (UWD) recorded about 33.1 microradians of deflationary tilt during this episode. 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.

More information about the eruption can be found in earlier reports:

Status Report on Fountain Height and Loss of V3 camera (10:41 AM HST)
Volcano Activity Notice for Start of Eruption (8:48 AM HST)
Kīlauea Update for December 6 (8:25 AM HST)

Most episodes of Halemaʻumaʻu lava fountaining since the eruption started on December 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 December 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.

Recent Observations:
[Volcanic cloud height] Unknown
[Other volcanic cloud information] Sulfur dioxide emission rate is typically 1,200-1,500 tonnes/day between eruptive episodes
[Ballistics] N/A
[Lava flow/dome] N/A
[Lava flow] N/A

Hazard Analysis:
[General hazards] Pele's hair and tephra may affect areas downwind of eruptive vents
[Ash cloud] N/A
[Ashfall] N/A
[Lava flow/dome] N/A
[Pyroclastic flow] N/A
[Mud flow] N/A
[Volcanic gas] Usually 1,200-1,500 tonnes/day SO2 between eruptive episodes
[Lava flow] May continue to exhibit slow movement or incandescence as the cool and solidify over the coming days

Remarks:

Hazard Analysis: 

This episodic eruption is occurring within a closed area of Hawai'i Volcanoes National Park. High levels of volcanic gas—primarily water vapor (H₂O), carbon dioxide (CO₂), and sulfur dioxide (SO₂)—are one hazard of concern, as this hazard can have far-reaching effects downwind. As SO₂ is continuously released from the summit during an eruption, it will react in the atmosphere to create the visible haze known as vog (volcanic smog) downwind of Kīlauea. SO₂ and vog may cause respiratory and other problems at high concentrations. Further information on vog can be found at https://vog.ivhhn.org/

Another hazard closer to the vent is fallout of Pele's hair and other volcanic fragments from lava fountains. Pele's hair is strands of volcanic glass often produced by lava fountaining activity and can be carried well over 10 miles (15 kilometers) from the vent. Other hot glassy volcanic fragments including Peleʻs hair, volcanic ash, pumice, scoria, and reticulite can fall on the ground within 1-2 miles (1-3 kilometers) of the eruptive vent(s) with the highest concentrations downwind of the vent(s). Pumice and other volcanic fragments have fallen on Highway 11 west of Hawaiʻi Volcanoes National Park depending on wind and eruption conditions. Strong winds may waft light particles, including Pele's hair, to greater distances downwind. Once they are on the ground, Pele's hair can sometimes cluster and tangle together, giving it the appearance of a tumbleweed. The extent of Pele's hair deposition is dependent on lava fountaining activity and current wind conditions. Residents and visitors should minimize exposure to Pele's hair and other glassy volcanic fragments, which can cause skin and eye irritation. More information about how Pele's hair, its hazards, and what to do is available here: https://www.usgs.gov/observatories/hvo/news/volcano-watch-recent-lava-fountains-highlight-peles-hair-hazards. A recently updated Frequently Asked Questions document that includes information about potential health effects of Pele's hair is available here: https://vog.ivhhn.org/sites/default/files/PelesHair_FAQs_v2.pdf

Hawaiian lava flows generally advance slowly downslope, and during this eruption flows have been confined to Halemaʻumaʻu crater and the southwest side of Kaluapele, Kīlauea's summit caldera.

Other significant hazards also remain around Kīlauea caldera from Halemaʻumaʻu crater wall instability, ground cracking, and rockfalls that can be enhanced by earthquakes within the area closed to the public. This underscores the extremely hazardous nature of Kīlauea's caldera rim surrounding Halemaʻumaʻu crater, an area that has been closed to the public since late 2007.

Contacts:

askHVO@usgs.gov

Next Notice:

HVO continues to closely monitor Kīlauea and will issue a VAN/VONA at the start of the next eruptive episode. If possible, HVO will also issue a Status Report beforehand at the onset of low-level precursory activity. Regularly scheduled daily updates for Kīlauea are posted on the HVO website at https://www.usgs.gov/volcanoes/kilauea/volcano-updates

More Information:

Hawaiʻi Volcanoes National Park visitor information: https://www.nps.gov/havo/index.htm
Kīlauea activity summary also available by phone: (808) 967-8862
Kīlauea webcam images: https://www.usgs.gov/volcanoes/kilauea/webcams
Kīlauea photos/video: https://www.usgs.gov/volcanoes/kilauea/photo-and-video-chronology
Kīlauea lava-flow maps: https://www.usgs.gov/volcanoes/kilauea/maps
Kīlauea FAQs: https://www.usgs.gov/volcanoes/kilauea/faqs

Subscribe to these messages: https://volcanoes.usgs.gov/vns2/
Summary of volcanic hazards from eruptions: https://www.usgs.gov/observatories/hvo/hazards
Recent earthquakes in Hawaiʻi (map and list): https://www.usgs.gov/observatories/hvo
Explanation of Volcano Alert Levels and Aviation Color Codes: https://www.usgs.gov/programs/VHP/volcanic-alert-levels-characterize-conditions-us-volcanoes

(1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA)
(2) Issued:	(20251207/0708Z)
(3) Volcano:	Kilauea (VNUM #332010)
(4) Current Color Code:	ORANGE
(5) Previous Color Code:	ORANGE
(6) Source:	Hawaiian Volcano Observatory
(7) Notice Number:	2025/H537
(8) Volcano Location:	N 19 deg 25 min W 155 deg 17 min
(9) Area:	Hawaii
(10) Summit Elevation:	4091 ft (1247 m)
(11) Volcanic Activity Summary:	Episode 38 of the ongoing Halemaʻumaʻu eruption ended abruptly at 8:52 p.m. HST on December 6 after 12.1 hours of continuous lava fountaining. The south vent stopped erupting at approximately 8:52 p.m. HST, marking the end of the episode. The dual north vents stopped erupting much earlier at approximately 11:50 a.m. Lava fountains reached heights of up to 1,000-1,200 ft (300-370 m) during episode 38. Fountains were down to about 400 feet (120 meters) high just before the abrupt end of the eruption. Lava fountaining lasted for 12.1 hours and produced an estimated 16 million cubic yards (12 million cubic meters) of lava. The combined average eruption rate was over 250 cubic yards per second (190 cubic meters per second) from the lava fountains. Sustained lava fountains began erupting from two vents located within the north cone at 8:45 a.m. HST on December 6 after just over 5 hours of precursory lava overflows. The south vent then began fountaining at 8:49 a.m. By 9:15 a.m. a rare triple fountain event was underway with the two north vents and the south vent all erupting together at heights of about 500 feet (150 meters). By 9:40 a.m. the south vent fountain grew to about twice as high as the north vent fountains. The highest peak or instantaneous effusion rate of 1,300 cubic yards per second (1,000 cubic meters per second) occurred just before 10 a.m. when the south vent exploded. The enlarged south vent produced an inclined fountain over 1,000 feet (300 meters) tall that sprayed the south wall of Halemaʻumaʻu crater. Hot pumice and molten spatter from this fountain destroyed the HVO "V3" streaming camera site. Lava flows from this episode's fountains covered 50-60% of the floor of Halemaʻumaʻu crater. Lava flows near the vents and on the floor of Halemaʻumaʻu within the southern part of Kaluapele (Kīlauea caldera) may continue to exhibit slow movement or incandescence as they cool and solidify over the coming days. Volcanic gas emissions have greatly decreased with the end of the eruption. Earlier today the gas plume reached over 20,000 feet (6000 meters) above sea level. Tephra including Pele's hair and fine ash carried in lower levels of the plume fell in the town of Pahala and other communities southwest of the vents. Satellite imagery showed the upper regions of the gas and ash cloud moved due east of the summit across lower Puna and well out to sea before turning south. Reticulite pieces up to the size of a baseball fell along Chain of Craters Road east of Kīlaueaʻs summit transported by the high eastern plume. The extremely high effusion rates early in the eruption provided the gas and heat that drove this enormous plume. The Uēkahuna tiltmeter (UWD) recorded about 33.1 microradians of deflationary tilt during this episode. 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. More information about the eruption can be found in earlier reports: Status Report on Fountain Height and Loss of V3 camera (10:41 AM HST) Volcano Activity Notice for Start of Eruption (8:48 AM HST) Kīlauea Update for December 6 (8:25 AM HST) Most episodes of Halemaʻumaʻu lava fountaining since the eruption started on December 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 December 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.
(12) Volcanic cloud height:	Unknown
(13) Other volcanic cloud information:	Sulfur dioxide emission rate is typically 1,200-1,500 tonnes/day between eruptive episodes
(14) Remarks:	Hazard Analysis:  This episodic eruption is occurring within a closed area of Hawai'i Volcanoes National Park. High levels of volcanic gas—primarily water vapor (H₂O), carbon dioxide (CO₂), and sulfur dioxide (SO₂)—are one hazard of concern, as this hazard can have far-reaching effects downwind. As SO₂ is continuously released from the summit during an eruption, it will react in the atmosphere to create the visible haze known as vog (volcanic smog) downwind of Kīlauea. SO₂ and vog may cause respiratory and other problems at high concentrations. Further information on vog can be found at https://vog.ivhhn.org/ Another hazard closer to the vent is fallout of Pele's hair and other volcanic fragments from lava fountains. Pele's hair is strands of volcanic glass often produced by lava fountaining activity and can be carried well over 10 miles (15 kilometers) from the vent. Other hot glassy volcanic fragments including Peleʻs hair, volcanic ash, pumice, scoria, and reticulite can fall on the ground within 1-2 miles (1-3 kilometers) of the eruptive vent(s) with the highest concentrations downwind of the vent(s). Pumice and other volcanic fragments have fallen on Highway 11 west of Hawaiʻi Volcanoes National Park depending on wind and eruption conditions. Strong winds may waft light particles, including Pele's hair, to greater distances downwind. Once they are on the ground, Pele's hair can sometimes cluster and tangle together, giving it the appearance of a tumbleweed. The extent of Pele's hair deposition is dependent on lava fountaining activity and current wind conditions. Residents and visitors should minimize exposure to Pele's hair and other glassy volcanic fragments, which can cause skin and eye irritation. More information about how Pele's hair, its hazards, and what to do is available here: https://www.usgs.gov/observatories/hvo/news/volcano-watch-recent-lava-fountains-highlight-peles-hair-hazards. A recently updated Frequently Asked Questions document that includes information about potential health effects of Pele's hair is available here: https://vog.ivhhn.org/sites/default/files/PelesHair_FAQs_v2.pdf Hawaiian lava flows generally advance slowly downslope, and during this eruption flows have been confined to Halemaʻumaʻu crater and the southwest side of Kaluapele, Kīlauea's summit caldera. Other significant hazards also remain around Kīlauea caldera from Halemaʻumaʻu crater wall instability, ground cracking, and rockfalls that can be enhanced by earthquakes within the area closed to the public. This underscores the extremely hazardous nature of Kīlauea's caldera rim surrounding Halemaʻumaʻu crater, an area that has been closed to the public since late 2007.
(15) Contacts:	askHVO@usgs.gov
(16) Next Notice:	HVO continues to closely monitor Kīlauea and will issue a VAN/VONA at the start of the next eruptive episode. If possible, HVO will also issue a Status Report beforehand at the onset of low-level precursory activity. Regularly scheduled daily updates for Kīlauea are posted on the HVO website at https://www.usgs.gov/volcanoes/kilauea/volcano-updates More Information: Hawaiʻi Volcanoes National Park visitor information: https://www.nps.gov/havo/index.htm Kīlauea activity summary also available by phone: (808) 967-8862 Kīlauea webcam images: https://www.usgs.gov/volcanoes/kilauea/webcams Kīlauea photos/video: https://www.usgs.gov/volcanoes/kilauea/photo-and-video-chronology Kīlauea lava-flow maps: https://www.usgs.gov/volcanoes/kilauea/maps Kīlauea FAQs: https://www.usgs.gov/volcanoes/kilauea/faqs