ALASKA VOLCANO OBSERVATORY DAILY UPDATE
U.S. Geological Survey
Saturday, February 28, 2026, 9:46 AM AKST (Saturday, February 28, 2026, 18:46 UTC)
Lava continues to erupt slowly within the summit crater of Great Sitkin Volcano. Seismic activity continues at a very low level. Satellite and webcam images were cloudy.
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, webcams, and regional infrasound and lightning networks.
To view monitoring data and other information about Great Sitkin: https://avo.alaska.edu/volcano/great-sitkin
Unrest continues at Shishaldin Volcano. Seismic and infrasound activity remains elevated, with numerous small earthquakes and frequent infrasound detections being observed. A weak gas plume was seen in satellite and webcam images. Sulfur dioxide emission and slightly elevated surface temperatures were also seen in satellite views.
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.
To view monitoring data and other information about Shishaldin: https://avo.alaska.edu/volcano/shishaldin
Matt Haney, Scientist-in-Charge, USGS mhaney@usgs.gov (907) 786-7497
David Fee, Coordinating Scientist, UAFGI dfee1@alaska.edu (907) 378-5460
Contact AVO: https://avo.alaska.edu/contact
The Alaska Volcano Observatory is a cooperative program of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute, and the Alaska Division of Geological and Geophysical Surveys.
ALASKA VOLCANO OBSERVATORY WEEKLY UPDATE
U.S. Geological Survey
Friday, February 27, 2026, 11:55 AM AKST (Friday, February 27, 2026, 20:55 UTC)
Lava continues to slowly erupt within the summit crater at Great Sitkin Volcano. Cloudy conditions obscured satellite and webcam views of the volcano throughout the week. Seismic activity remains low, with the detection of occasional small volcanic earthquakes and seismic signals from small rockfalls within the crater.
The current lava eruption began in July 2021 and has filled most of the summit crater and advanced into the 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 web cameras, and regional infrasound and lightning networks.
Great Sitkin Volcano is a basaltic andesite volcano that occupies most of the northern half of Great Sitkin Island, a member of the Andreanof Islands group in the central Aleutian Islands. It is located 26 miles (42 km) east of the community of Adak. The volcano is a composite structure consisting of an older dissected volcano and a younger parasitic cone with a ~1 mile (1.6 km)-diameter summit crater. A steep-sided lava dome, emplaced in the crater during an eruption in 1974, has been mostly buried by the ongoing eruption. The 1974 eruption produced at least one ash cloud that likely exceeded an altitude of 25,000 ft (7.6 km) above sea level. A poorly documented eruption also occurred in 1945, producing a lava dome that was partially destroyed in the 1974 eruption. Within the past 280 years a large explosive eruption produced pyroclastic flows that partially filled the Glacier Creek valley on the southwest flank.
Signs of volcanic unrest at Shishaldin Volcano continue. Seismic and infrasound activity remains elevated, with numerous small earthquakes, frequent infrasound detections, and periods of volcanic tremor being observed throughout the week. Minor steaming was also consistently observed in daytime webcam views, and sulfur dioxide emissions were seen in satellite data most days. Barely elevated surface temperatures, probably related to the gas plume, were also seen occasionally at the volcano's summit in satellite views.
Shishaldin Volcano is monitored by local seismic and infrasound sensors, web cameras, and a telemetered geodetic network. In addition to the local monitoring network, the Alaska Volcano Observatory uses nearby geophysical networks, regional infrasound and lightning data, and satellite data to monitor the volcano.
Shishaldin Volcano, located near the center of Unimak Island in the eastern Aleutian Islands, is a conical stratovolcano with a base diameter of approximately 10 miles (16 km). It is one of the most active volcanoes in the Aleutian volcanic arc, with at least 54 episodes of unrest, including over 28 confirmed eruptions since 1824. Most eruptions are relatively small, although activity during the 1999 and 2023 eruptions generated ash columns that reached up to 46,000 ft (16 km) above sea level.
A small explosion occurred Sunday evening (February 22) at Semisopochnoi volcano and was detected by seismic and infrasound sensors on Semisopochnoi Island. Weather conditions were cloudy at the time, and no eruption cloud or deposits were detected subsequently in satellite or webcam data. Seismicity quickly returned to background levels, and no additional activity has been detected. This unheralded event posed little hazard, as it was localized to Mount Young, which last erupted in 2023. The north cone of Mount Young—the likely source of the explosion—hosts a crater lake and has vigorous fumaroles that produce a small gas plume. The Aviation Color Code and Volcano Alert Level at the volcano were not changed following this event and remain at GREEN and NORMAL.
Semisopochnoi is monitored by a local seismic and infrasound network, local web cameras, regional lightning and infrasound sensors, and satellite data.
Semisopochnoi volcano occupies the largest, young volcanic island in the western Aleutians. The volcano is dominated by a 5-mile (8 km) diameter caldera that contains a small lake and several post-caldera cones and craters. The age of the caldera is not known with certainty but is likely early Holocene. Prior to 2018, the previous known historical eruption of Semisopochnoi volcano occurred in 1987, probably from Sugarloaf Peak on the south coast of the island, but details are lacking. Another prominent, young post-caldera landform is Mount Young, a three-peaked cone cluster in the southwest part of the caldera. Mount Young has been intermittently active since 2018. The island is uninhabited and part of the Alaska Maritime National Wildlife Refuge. It is located 40 miles (65 km) northeast of Amchitka Island and 130 miles (200 km) west of Adak.
Matt Haney, Scientist-in-Charge, USGS mhaney@usgs.gov (907) 786-7497
David Fee, Coordinating Scientist, UAFGI dfee1@alaska.edu (907) 378-5460
Contact AVO: https://avo.alaska.edu/contact
The Alaska Volcano Observatory is a cooperative program of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute, and the Alaska Division of Geological and Geophysical Surveys.
CASCADES VOLCANO OBSERVATORY WEEKLY UPDATE
U.S. Geological Survey
Friday, February 27, 2026, 12:59 PM PST (Friday, February 27, 2026, 20:59 UTC)
Activity Update: All volcanoes in the Cascade Range of Oregon and Washington are at normal background activity levels. These include Mount Baker, Glacier Peak, Mount Rainier, Mount St. Helens, and Mount Adams in Washington State and Mount Hood, Mount Jefferson, Three Sisters, Newberry, and Crater Lake in Oregon.
Past Week Observations: Small earthquakes were detected at Mount Rainier, Mount St. Helens, and the Three Sisters region during the past week. Field crews repaired a monitoring station at Mount St. Helens. All monitoring data are consistent with background activity levels in the Cascade Range.
The U.S. Geological Survey Cascades Volcano Observatory and the University of Washington Pacific Northwest Seismic Network continue to monitor Washington and Oregon volcanoes closely and will issue additional notifications as warranted.
Website Resources
For images, graphics, and general information on Cascade Range volcanoes: https://www.usgs.gov/observatories/cvo
For seismic information on Oregon and Washington volcanoes: http://www.pnsn.org/volcanoes
For information on USGS volcano alert levels and notifications: https://www.usgs.gov/programs/VHP/volcano-notifications-deliver-situational-information
Seth Moran, Scientist-in-Charge, Cascades Volcano Observatory, smoran@usgs.gov
General inquiries: askCVO@usgs.gov
Media inquiries: volcanomedia@usgs.gov
HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
U.S. Geological Survey
Saturday, February 28, 2026, 9:01 AM HST (Saturday, February 28, 2026, 19:01 UTC)
Activity Summary:
The Halemaʻumaʻu eruption of Kīlauea is paused. Episode 42 ended February 15 at 11:38 p.m. HST. Preliminary models suggest the likely forecast window for the onset of episode 43 lava fountaining is March 8-15.
No significant activity has been noted along Kīlauea’s East Rift Zone or Southwest Rift Zone.
A recap of episode 42 can be found in this Status Report.
Significant changes in activity between Daily Updates are posted here: https://www.usgs.gov/observatories/hvo/observatory-messages
Summit Observations:
No glow could be seen from the vents last night. This morning, both vents remain quiet and emitting steady gas plumes. Low seismic tremor continues at the summit, punctuated by bursts every 5-10 minutes. There were 8 small earthquakes located across the summit region in the past 24 hours with the largest being magnitude 1.6.
Summit tiltmeters began recording inflation yesterday around noon, and this trend continued throughout the night. The UWD tiltmeter has recorded recovery of nearly 19.3 microradians of inflationary tilt since the end of episode 42, with about 1.7 microradians of net deflation over the past 24 hours.
Sulfur dioxide (SO2) emission rates from the summit have been averaging 1000-1500 t/d, typical of these eruptive pauses. This morning, due to weak southerly winds, gas is rising slowly from the vents and blanketing the caldera and surrounding areas.
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 initial rapid rebound of tilt and glow from both vents indicate that another fountaining episode is likely. The overall inflationary trend continues to be interrupted by periods of no inflation or slight deflation recorded across all four summit tiltmeters that may impact the onset of episode 43 fountaining. Periods of weak deflation or no inflation have not been common in the early stages of repose between fountaining episodes. These changes in tilt rate are not predictable and create uncertainty in modeling the onset of episode 43 fountaining. Models suggest the forecast window for the start of episode 43 fountaining is likely between March 8 and March 15. Additional data are needed to more accurately determine the forecast window.
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 episode 41:
A recap of episode 42 can be found in this Status Report.
Resources:
The following links provide more information about the current eruption that began on December 23, 2024:
Hazards:
This episodic eruption is occurring within a closed area of Hawai'i Volcanoes National Park.
Other significant hazards exist around Kīlauea caldera from Halemaʻumaʻu crater wall instability, ground cracking, and rockfalls that can be enhanced by earthquakes. 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. 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.
More Information:
The Hawaiian Volcano Observatory is one of five volcano observatories within the U.S. Geological Survey and is responsible for monitoring volcanoes and earthquakes in Hawaiʻi and American Samoa.
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
HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
U.S. Geological Survey
Friday, February 27, 2026, 9:03 AM HST (Friday, February 27, 2026, 19:03 UTC)
Activity Summary:
The Halemaʻumaʻu eruption of Kīlauea is paused. Episode 42 ended February 15 at 11:38 p.m. HST. Preliminary models suggest the likely forecast window for the onset of episode 43 lava fountaining is March 6-16.
No significant activity has been noted along Kīlauea’s East Rift Zone or Southwest Rift Zone.
A recap of episode 42 can be found in this Status Report.
Significant changes in activity between Daily Updates are posted here: https://www.usgs.gov/observatories/hvo/observatory-messages
Summit Observations:
Little-to-no glow could be seen from the vents last night. This morning, both vents remain quiet and emitting steady gas plumes. Low seismic tremor continues at the summit, punctuated by more energetic bursts every 5-10 minutes. These bursts have been associated with brief increases in gas emission and increases in glow from the vents at night. There were two earthquakes less than M1.0 located in the summit region in the past 24 hours.
Summit tiltmeters began recording mild deflation early yesterday morning, and this trend continue throughout the day. The UWD tiltmeter has recorded recovery of nearly 17.6 microradians of inflationary tilt since the end of episode 42, with about 0.2 microradians of net deflation over the past 24 hours.
Sulfur dioxide (SO2) emission rates from the summit have been averaging 1000-1500 t/d, typical of these eruptive pauses. This morning, due to weak southerly winds, gas is rising slowly from the vents and blanketing the caldera and surrounding areas.
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 initial rapid rebound of tilt and glow from both vents indicate that another fountaining episode is likely. The overall inflationary trend has been interrupted by periods of no inflation or slight deflation recorded across all four summit tiltmeters that may impact the onset of episode 43 fountaining. Periods of weak deflation or no inflation have not been common in the early stages of repose between fountaining episodes. These changes in tilt rate are not predictable and create uncertainty in modeling the onset of episode 43 fountaining. Preliminary models suggest the forecast window for the start of episode 43 fountaining is likely between March 6 and March 16. Additional data are needed to more accurately determine the forecast window.
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 episode 41:
A recap of episode 42 can be found in this Status Report.
Resources:
The following links provide more information about the current eruption that began on December 23, 2024:
Hazards:
This episodic eruption is occurring within a closed area of Hawai'i Volcanoes National Park.
Other significant hazards exist around Kīlauea caldera from Halemaʻumaʻu crater wall instability, ground cracking, and rockfalls that can be enhanced by earthquakes. 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. 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.
More Information:
The Hawaiian Volcano Observatory is one of five volcano observatories within the U.S. Geological Survey and is responsible for monitoring volcanoes and earthquakes in Hawaiʻi and American Samoa.
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