USGS Volcanoes: Notices released in the last day.

Lava continues to erupt slowly within the summit crater of Great Sitkin Volcano. A number of small local earthquakes were detected. Partly cloudy satellite imagery showed weakly elevated surface temperatures at known location of the active lava flow. Webcam views obscured by clouds.

The current lava eruption began in July 2021 and since then has filled most of the summit crater and advanced into valleys below. There have been no explosions at Great Sitkin Volcano since an event in May 2021. The volcano is monitored using local seismic and infrasound sensors, satellite data and webcams, and regional infrasound and lightning networks.

Shishaldin Volcano continues to experience unrest with numerous small earthquakes detected over the past day. Both satellite and webcam views were obscured by clouds.

Local seismic and infrasound sensors, web cameras, and a geodetic network are used to monitor Shishaldin Volcano. In addition to the local monitoring network, AVO uses nearby geophysical networks, regional infrasound and lighting data, and satellite images to detect eruptions. 

Activity Summary: 

Episode 41 of the ongoing Halemaʻumaʻu eruption began around 11:10 a.m. HST on January 24, 2026. Tephra fall has been reported in public viewing areas within Hawaiʻi Volcanoes National Park, Volcano Village, Mauna Loa Estates, and Ohia Estates. As of 12:10 p.m., both north and south vent fountains were over 500 m (1640 feet) tall.

Episode 41 followed several days of low-level activity, starting with weak spattering from north vent the night January 21–22, with the first overflows from north vent the night of January 22. This morning at 3:52 a.m. north vent started continuously overflowing. Low fountains increased in height to 10-15 feet (3-5 meters) and both the north vent effusion rate and overflow activity increased at about 4:47 a.m. HST. South vent also had overflows. The south vent had its first overflow at 4:11 a.m. HST this morning, the first of four short-lived overflows that remained close to the vent. Starting at 6:40 a.m., overflows became larger and longer-lived, sending flows out onto the floor of Halemaʻumaʻu crater.

The tiltmeter at UWD started recording deflation at about 10:15 a.m. this morning, and summit seismometers started recording increasing tremor around 11:10 a.m. The episode started at 11:10 a.m. with both vents fountaining. By 12:10. p.m., both north and south vent fountains were about 500 m (1640 feet) tall.

• All eruptive activity is confined to Halemaʻumaʻu crater within Hawaiʻi Volcanoes National Park, with tephra fall in nearby communities; commercial airports in Hawaii County (KOA and ITO) are unlikely to be affected by this activity.
• Near-surface winds are weakly from the south and may carry gas and solid material to the north. Upper-level winds are stronger and may carry lofted plume material to the east.
• Three Kīlauea summit livestream videos that show eruptive lava fountains are available here: V1cam, V2cam, V3cam.
• KPcam and MKcam provide views of the plume height for aviation purposes.

During previous episodes, fountains reached heights of more than 1,000 feet (300 meters) and the eruptive plume reached heights of up to 20,000 feet (6,000 meters) above ground level soon after sustained high fountaining began.

The tiltmeter at Uēkahuna (UWD) has recorded approximately 18 microradians of inflationary tilt between the end of episode 40 and the start of episode 41. As of 12:10 p.m., UWD has recorded about 5.7 microradians of deflationary tilt.

Most episodes of Halemaʻumaʻu lava fountaining since 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.

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.

Hazards: 

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 major 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 major hazard 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 that can be carried well over 10 miles (15 kilometers) from the vent. Other hot glassy volcanic fragments (tephra) including volcanic ash, pumice, scoria, and reticulite can fall on the ground within 1-3 miles (1-5 kilometers) of the eruptive vent(s), with the highest concentrations immediately downwind of the vent(s). Various volcanic fragments have fallen on Highway 11 west of Hawai'i Volcanoes National Park at times, depending on wind and eruption conditions. Strong winds may waft light particles, including Pele's hair, to greater distances downwind. Once 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 wind conditions. Residents and visitors should minimize exposure to Pele's hair and other glassy volcanic fragments, which can cause skin and eye irritation and can also contaminate catchment water supplies. 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.

Episode 41 of lava fountaining in Halemaʻumaʻu began at the summit of Kīlauea began at 11:10 a.m. HST on January 24. 

Ground-level sensors near the eruptive vents indicate that winds are light and blowing from the south southeast direction, which suggests that volcanic gas emissions and volcanic material may be distributed to the north northwest direction from Halemaʻumaʻu. Winds are forecast to be light and variable over the next several hours.

• All eruptive activity is confined to Halemaʻumaʻu crater within Hawaiʻi Volcanoes National Park
• Three Kīlauea summit livestream videos that show eruptive lava fountains are available here: https://youtube.com/@usgs/streams 
• KPcam and MKcam provide views of the plume height for aviation purposes
• Additional short updates as the episode progresses will be posted here: https://www.usgs.gov/observatories/hvo/observatory-messages 
• Timeline of eruptive episodes since December 23, 2024: https://www.usgs.gov/volcanoes/kilauea/science/eruption-information 

Most lava fountaining episodes since December 23, 2024, have continued for a day or less.

Activity Summary:

Precursory overflows began from the north vent at 3:52 a.m. HST and continued since then. The forecast based on inflationary tilt models for the onset of the next lava fountaining episode is most likely today, January 24, or possibly tommorrow, January 25, if inflation is interrupted. Micro-seismicity continues in the summit region, but is much less energetic than earlier this week. No significant activity has been noted along Kīlauea’s East Rift Zone or Southwest Rift Zone.

Significant changes in activity between Daily Updates are posted here: https://www.usgs.gov/observatories/hvo/observatory-messages

Summit Observations:                                                                                                                        

Webcam views of Halemaʻumaʻu showed consistent strong glow from both the north and south vents, with frequent spattering at flames from the north vent until early morning. Spattering increased in intensity and the north vent began overflowing at 3:52 a.m. HST. Low fountains increased in height to 10-15 feet (3-5 meters) and effusion rate from the north vent at about 4:47 a.m. HST and overflows increased in size. The north vent has remained continuously active since the onset of overflows. The south vent has overflowed eight times this morning (4:11, 5:18, 6:13, 6:28, 6:40, 6:57, 7:14, 7:22 a.m. HST). The first four were short-lived and remained close to the vent. The four latest overflows were larger lasting 10-15 minutes and sent flows out onto the floor of Halemaʻumaʻu crater. Constant low-level tremor continues this morning.

There was only one very short period of elevated micro-seismicity occurred over the past day at around 8:30 p.m. HST January 23, but it had no impact on tilt rate at UWD. Only eight earthquakes were large enough to be located over the past 24 hours (all magnitude 1 or less) beneath the summit. Earthquake locations continue to be spread fairly widely beneath the summit region, as the seismicity is related to migrating magmatic pressure within the summit region. Currently, seismic events donʻt appear to be having a direct impact on the eruption. For more information see prior Daily Updates and this Information Statement for more details: https://volcanoes.usgs.gov/hans-public/notice/DOI-USGS-HVO-2026-01-23T03:39:44+00:00.

Since the end of episode 40, the UWD tiltmeter has recorded 18.5 microradians of inflationary tilt, with net 1.6 microradians of inflation over the past 24 hours. The one small period of micro-seismicity had no impact on the tilt at UWD.

The sulfur dioxide (SO₂) emission rate from the summit was last measured on January 14 at 1,550 tonnes per day, which is within the typical range of 1,000 to 5,000 tonnes of SO₂ per day observed during previous eruptive pauses. This is considerably lower than rates observed during lava fountaining episodes. Current winds at the summit are light and variable with plumes rising nearly vertically. The NWS predicts light winds from the east and southeast today, suggesting that plumes might move to the west and northwest if episode 41 begins today.

Rift Zone Observations:

Rates of seismicity and ground deformation remain very low in the East Rift Zone and Southwest Rift Zone. SO₂ emissions from the East Rift Zone remain below the detection limit.

Analysis:

The rapid rebound of inflationary tilt, glow and spatter from the vents, and presence of low-level volcanic tremor after episode 40 indicate that another lava fountaining episode is likely. Everything currently points to resumption of fountaining episodes rather than a change in vent location. The continued repressurization of the Halemaʻumaʻu magma reservoir, continuous lava flows from the north vent all indicate episode 41 fountaining will take place in the next day. While seismic swarms continue, their intensity is reduced as well as their impact on reinflation of the summit. Models and activity indicate the onset of episode 41 lava fountaining is most likely to occur today January 24 with a slight possibility of tomorrow, January 25, if inflation is interupted by a significant seismic swarm or other event. 

Kīlauea has been erupting episodically since December 23, 2024, primarily from two vents (north and south) in Halema‘uma‘u. Eruptive episodes, which generally last for less than 12 hours, are separated by pauses that can be as long as over two weeks.

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.

Please see the Hawaiʻi Volcanoes National Park website for visitor information: https://www.nps.gov/havo/index.htm

Recap of Last Episode:

Episode 40 was preceded by precursory overflows that began from the south vent on January 8. Over the following days, dome fountains would form in the south vent, feeding overflows that occurred at rates of several per hour, while the north vent produced lava flows less frequently though spattering was often visible within the vent. On the morning of January 12, the north vent appeared to have a constricted opening, generated an arcuate spatter fountain that grew in vigor dramatically at 8:13 a.m. Strong deflation and an increase in tremor marked the start of episode 40 at 8:22 a.m. HST, when north vent fountains reached about 100 feet (30 meters) high. North vent fountain heights peaked at 800 feet (250 meters) high just before 10 a.m. With weak winds, the eruptive plume during episode 40 rose vertically to over 13,000 feet (4000 meters) above ground level before moving to southeast at higher altitudes. Most tephra from episode 40 lava fountains fell west of Halema'uma'u but also occasionally to the northwest and southwest as seen on V1 and V3 cams, with reticulite as large as 2 inches (5 cm) falling at the Uēkahuna Overlook in Hawaiʻi Volcanoes National Park briefly just after 10 a.m. Large whirlwinds or "puahiohio" also occurred during episode 40 and were visible in the livestreams. Episode 40 lava fountaining from the north vent stopped at approximately 7:04 p.m. HST on January 12 after 9.7 hours of sustained fountaining. While the south vent remained open and visibly degassing throughout episode 40, with occasional spatter visible, it did not produce a fountain during this episode. The highest peak or instantaneous effusion rate of 460 cubic yards (350 cubic meters) per second occurred around noon on January 12. Episode 40 ended with an average effusion rate of 250 cubic yards per second (190 cubic meters per second). An estimated 7.1 million cubic yards (5.5 million cubic meters) of lava erupted and covered about 50–60% of Halemaʻumaʻu crater floor. The Uēkahuna tiltmeter (UWD) recorded about 17 microradians of deflationary tilt during episode 40.

The following links provide more information about the current eruption that began on December 23, 2024:

• Eruption resources, including the most recent map and a timeline of eruption episodes since December 23, 2024: https://www.usgs.gov/volcanoes/kilauea/science/eruption-information
• Short messages tracking the evolution of the fountains and eruptive activity can be found here: https://www.usgs.gov/observatories/hvo/observatory-messages 
• Three Kīlauea summit livestream videos that show eruptive lava fountains are available here: https://www.youtube.com/@usgs/streams
• Summit eruption webcams: https://www.usgs.gov/volcanoes/kilauea/summit-webcams
• Volcano Watch article on gas pistons: https://www.usgs.gov/observatories/hvo/news/volcano-watch-so-what-earth-or-least-kilauea-a-gas-piston

Hazards:

This episodic eruption is occurring within a closed area of Hawai'i Volcanoes National Park.

• Volcanic Gas: high levels of volcanic gas—primarily water vapor (H₂O), carbon dioxide (CO₂), and sulfur dioxide (SO₂)—are continually released during an eruption. Emissions can remain locally hazardous in the areas immediately downwind of the vents, even when the vents are not actively erupting. SO₂ reacts in the atmosphere to create vog (volcanic air polution) downwind. SO₂ and vog may cause respiratory and other problems at high concentrations. Further information on vog can be found at https://vog.ivhhn.org/
• Tephra: small glassy volcanic fragments—volcanic ash, pumice, scoria, and reticulite—are created by the lava fountains. Larger particles fall near the vents while light particles may be wafted greater distances. These particles may be remobilized during windy conditions following recent eruptive episodes. Residents and visitors should minimize exposure to these fragments, which can cause skin and eye irritation. More information is available here: https://vog.ivhhn.org/sites/default/files/PelesHair_FAQs_v2.pdf. Close to the vents, the tephra material on the crater rim is prone to cracking, slumping, and small landslides that sometimes expose hot and molten material within. 
• Lava flows: on the floor of Halemaʻumaʻu crater and the southwest side of Kaluapele, Kīlauea's summit caldera, remain hot and may slowly move in the days immediately following an eruptive episode. 

Other significant hazards also remain around Kīlauea caldera from Halemaʻumaʻu crater wall instability, ground cracking, and rockfalls that can be enhanced by earthquakes. 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.