USGS Volcanoes: Notices released in the last day.

Lava continues to erupt slowly within the summit crater of Great Sitkin Volcano. One small earthquake was detected in the past day. No activity was observed in mostly cloudy webcam and satellite images over the past day.

The current eruption began in July 2021. Since then, lava flows have 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, webcams, and regional infrasound and lightning networks.

Unrest continues with elevated seismic and infrasound activity. Clouds obscured satellite and webcam views of the volcano over the past day.

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 lightning data, and satellite images to detect eruptions. 

Strong southeasterly winds in the vicinity of Mount St. Helens have picked up loose volcanic ash erupted during the 1980 eruptions of Mount St. Helens and are carrying it to the northwest. The National Weather Service has issued a CWA for the low-level event and suggests that the maximum cloud height is 12,000 ft (3,658 m) above sea level. The National Weather Service expects strong southeasterly wind conditions to continue for several hours. 

This phenomenon is not the result of recent volcanic activity and occurs during times of high winds and dry snow-free conditions in the Mount St. Helens region. No eruption is in progress and Mount St. Helens remains at Aviation Color Code Green and Volcano Alert Level Normal. Resuspended volcanic ash should be considered hazardous and could be damaging to aircraft and health. 

For more information on volcanic ash and human health, visit the following website: http://volcanoes.usgs.gov/ash/

Official warnings about these ash resuspension events are issued by the National Weather Service: https://www.weather.gov/sew/ & https://www.weather.gov/pqr & https://www.weather.gov/zse. 

Forecasts of airborne ash hazard to aircraft: https://www.weather.gov/aviation/awc. Volcanic Ash Advisories: https://www.weather.gov/vaac/

Forecasts of ashfall: http://www.weather.gov/afc

Summit Observations:

Overflows from the north vent resumed yesterday at 11:08 AM HST and continued intermittently throughout the day with 12 recorded by sundown, as well as one overflow from the south vent. Numerous instances of spatter from all three vents (north, south, and west) were also observed. Conditions overnight led to difficult viewing, nonetheless spatter was visible from all vents, as well as an additional overflow accompanied by gas jetting from the north vent at 4:46 AM. Glow and flames from the vents also continued consistently through the night.

Summit tremor continued throughout the day, with a return to irregular tremor bursts around 12:15 PM. In the past 24 hours, there were 20 shallow earthquakes located across the summit region of Kīlauea, predominantly in the south caldera region. 

Summit tiltmeters have shown minor changes in tilt, with an overall slight inflationary trend over the past day. 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 yesterday indicate that magma remains very near the surface in the established vent complex and continues to be able to generate smaller 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. For further details, see the recent official notices listed below. 

• October 7 Status Report summarizing recent intrusive activity and implications: https://volcanoes.usgs.gov/hans-public/notice/DOI-USGS-HVO-2026-10-08T01:00:28+00:00 
• October 7 Hawaiʻi Volcanoes National Park News Release announcing closures related to recent activity: https://www.nps.gov/havo/learn/news/20261007-nr-trail-closures.htm 
• October 1 Volcano Watch summarizing recent intrusive activity: https://www.usgs.gov/observatories/hvo/news/volcano-watch-intrusion-during-eruption-summit-kilauea 
• October 1 Status Report published during recent intrusive activity: https://volcanoes.usgs.gov/hans-public/notice/DOI-USGS-HVO-2026-10-01T08:14:21+00:00
• September 15 Status Report on changes in activity and implications for this eruption: https://volcanoes.usgs.gov/hans-public/notice/DOI-USGS-HVO-2026-09-15T03:18:09+00:00 
• NOTE: Significant changes in activity between Daily Updates are posted here: https://www.usgs.gov/observatories/hvo/observatory-messages

Hazards:

Eruptive activity since December 2024 has been occurring within a closed area of Hawai'i Volcanoes National Park. However, recent intrusions highlight that the location of eruptive activity could change. Intrusions can also be hazardous with potential to cause earthquakes, ground cracks, and small landslides. The primary hazards at Kīlauea due to eruptive activity and/or intrusions are:

• 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 pollution) 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, Pele’s hair and reticulite—are created by the lava fountains. A combination of fountaining dynamics and wind conditions determines where tephra fall may occur for any given eruption episode. 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, eye, and respiratory irritation. More information and guidance on tephra fall hazards is available at https://seagrant.soest.hawaii.edu/resource-and-guidance-for-volcanic-tephra-fall/ and https://vog.ivhhn.org/sites/default/files/PelesHair_FAQs_v2.pdf 
• Lava flows: Hawaiian lava flows generally advance slowly downslope but destroy everything in their paths. Lava flows that erupt within Halemaʻumaʻu remain confined to the crater, including those during the eruption that started in December 2024. However, intrusive activity could result in lava flows outside of Halemaʻumaʻu. Hazards associated with active or recent lava flows include hot and glassy (sharp) surfaces that can cause serious burns, abrasions, and lacerations upon contact with unprotected or exposed skin; uneven and rough terrain can lead to falls and other injuries; hot temperatures that can cause heat exhaustion or dehydration, or in heavy rain can produce steamy ground-fog that can be acidic, severely limiting visibility and sometimes causing difficulty breathing.
• Earthquakes and ground cracks: Shallow magma movement and eruptions can produce minor to severe ground fractures and subsidence features. These ground cracks can continue to widen and offset as magma migration continues, may have unstable overhanging edges, and should be avoided. Other significant hazards exist around Kīlauea caldera from Halemaʻumaʻu crater wall instability, ground cracking, and rockfalls that can be enhanced by earthquakes.

Additionally, close to the eruptive vents, the tephra material on the crater rim is prone to cracking, slumping, and small landslides that sometimes expose hot and molten material within. 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.

HVO is issuing a weekly Volcano Observatory Notice for Aviation (VONA) and associated Volcano Activity Notices (VAN) which are now required to be reissued weekly for volcanoes at ORANGE. (VONA repeat interval is daily for volcanoes at RED and every two weeks for volcanoes at YELLOW).

Strong glow and intermittent spattering have been observed from the north, west, and south vents since October 6. Occasional overflows have also occurred from the north vent with approximately 20 small to moderate overflows on October 12 and an additional 3 small overflows on October 14. Activity may either lead to episode 55 high fountains or, alternatively, to opening of a new vent or emplacement of an intrusion. Forecast windows for episode 55 fountaining can no longer be modeled due to changes in conditions. Episode 54 fountaining ended at 7:33 p.m. HST on Tuesday, August 25, 2026. HVO continues to closely monitor ongoing activity. Please see the Daily Update for Kīlauea for more details.

• All eruptive vents and lava flows are confined to Halemaʻumaʻu crater within Hawaiʻi Volcanoes National Park. Tephra fall from volcanic ash clouds is greatest within 3 miles (5 km) of the vents, lighter ash and Peleʻs Hair may stay suspended for large distances from the vents.
• 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 
• Additional short updates shared during the episode can be found here: https://www.usgs.gov/observatories/hvo/observatory-messages 

Plumes of discolored water were seen in the ocean above Ahyi on October 9 and 11 this past week. Discolored greenish water was visible drifting more than 7 km from the summit of Ahyi. These plumes are likely associated with degassing and hydrothermal activity at the summit of the underwater volcano. No notable activity was detected in distal geophysical monitoring data over the past week. 

Eruptive activity at Ahyi seamount may present a hazard to mariners in the water above and near the volcano. The summit has shallowed over the course of previous eruptions to 180 feet (55 m) below sea level, but the lack of local real-time data means we are unable to forecast or warn of impending eruptions. We will continue to monitor satellite and distal hydroacoustic data for additional evidence for, or escalation of, volcanic activity.

NORTHERN MARIANAS VOLCANOES
No signs of unrest were detected at any Northern Mariana Island volcanoes besides Ahyi Seamount during the past week. 

Monitoring of Northern Mariana Islands Volcanoes

Northern Mariana Island volcanoes are monitored using seismo-acoustic sensors on Saipan, and by examining satellite imagery. We also use distant seismic stations in Guam and Chichijima, Japan, and hydroacoustic data from Wake Island, when available.

This level of monitoring can detect significant volcanic activity in the CNMI but cannot provide advanced warning of eruptions.

Due to a lack of geophysical monitoring on any of the volcanic islands, the following volcanoes have alert levels of UNASSIGNED: Anatahan, Sarigan, Farallon de Pajaros, Supply Reef, Maug, Asuncion, Agrigan, Pagan, Almagan, and Guguan.