ALASKA VOLCANO OBSERVATORY WEEKLY UPDATE
U.S. Geological Survey
Friday, July 10, 2026, 12:27 PM AKDT (Friday, July 10, 2026, 20:27 UTC)
Slow eruption of lava continues within the summit crater. Typical slightly elevated surface temperatures were observed throughout the week when cloud cover was not obscuring the volcano. Clear high-resolution satellite views of the summit show minor steaming from the lava flow as well. Seismic activity remains low, with occasional small volcanic earthquakes and seismic signals from minor rockfalls observed. Web camera observations showed no evidence of activity.
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, geodetic, 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.
Earthquake activity continues near Mount Kupreanof volcano, with magnitudes under 2.5 this week. The two largest earthquakes had magnitudes of 1.92 and 2.46 and occurred on July 10. Deep low-frequency earthquakes, greater than 12 miles (20 km) below sea level, were also observed. Sulfur dioxide gas emissions were detected in satellite images on July 7 and 8.
AVO released an Information Statement on June 22 summarizing the ongoing volcanic unrest from a magmatic intrusion beneath the volcano, which is also now detected in satellite ground deformation data (satellite interferometric radar or InSAR). More details can be found in the Information Statement on the AVO website: https://avo.alaska.edu/news/view/kupreanof-information-statement-june-22-2026.
There is no real-time geophysical monitoring network at Mount Kupreanof. The closest functioning seismometer is approximately 17 miles (27 km) to the east of the volcano as part of the Mount Veniaminof network. Mount Kupreanof is also monitored by satellite data, regional infrasound and lightning networks, and visual observations from pilots and mariners passing by the volcano.
Mount Kupreanof is a heavily glaciated stratovolcano on the Alaska Peninsula with no known historical eruptions. Very little is known about its eruptive history. A single debris flow or block-and-ash flow deposit with a suspected Holocene age has been mapped in a valley south of the volcano. Eruptions will likely produce lahars and pyroclastic flows on the volcano's flanks and into the surrounding uninhabited valleys. Ash plumes could affect communities and airplanes downwind of the volcano. A vigorous fumarole field just west of the summit produces persistent steam plumes.
Seismic and infrasound activity remain elevated, with numerous small earthquakes, frequent infrasound signals from small explosions within the summit crater, and volcanic tremor recorded this week. Satellite data showed elevated sulfur dioxide emissions and webcams showed steaming on most days.
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.
Matt Haney, Scientist-in-Charge, USGS, mhaney@usgs.gov (907) 786-7497
Jess Larsen, Acting Coordinating Scientist, UAFGI, jflarsen@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, July 10, 2026, 10:53 AM PDT (Friday, July 10, 2026, 17:53 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: During the past week, small earthquakes were detected at Mount St. Helens and Mount Rainier. On the afternoon of July 7, there was a minor debris flow detected within the Tahoma Creek at Mount Rainier. This event was similar to last week’s debris flow on July 3, and smaller than flows in 2023 and 2025. All of these flows likely result from a glacial outburst of water originating from the South Tahoma Glacier. At Mount St. Helens, field crews conducted maintenance at several monitoring stations and sampled springs for analysis, while at Mount Hood a field crew began installation of a new monitoring site.
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, Acting 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
Friday, July 10, 2026, 9:01 AM HST (Friday, July 10, 2026, 19:01 UTC)
Overview:
The Kīlauea summit eruption within Halemaʻumaʻu crater is paused. Overnight webcam views showed strong glow at both the north and south eruptive vents, and rare spatter from the north vent. The summit continued to record inflationary tilt over the past day. Current forecast models suggest that lava fountaining episode 51 is likely to start between July 11 and 13.
No significant activity has been noted along Kīlauea’s East Rift Zone or Southwest Rift Zone.
A summary of lava fountaining episode 50 is posted below.
NOTE: Significant changes in activity between Daily Updates are posted here: https://www.usgs.gov/observatories/hvo/observatory-messages
Summit Observations:
Strong glow was continuously visible from both the north and south vents overnight, along with rare spatter from the north vent, indicating the magma column is relatively high in both vents.
Low-level seismic tremor continues during the current pause with occasional bursts, likely in association with gas piston cycles in the eruptive vents. Earthquake activity beneath Kaluapele (Kīlauea caldera) remains low.
Kīlauea summit has recorded inflationary tilt over the past two days, but deflationary trends have interrupted the overall inflationary pattern following episode 50. Tilt recovery since the episode presently stands at about 14.1 microradians on the Uēkahuna (UWD) tiltmeter, an increase of 2 microradians since yesterday morning. Summit deflation totaled 15.3 microradians on UWD during episode 50.
The sulfur dioxide (SO2) emission rate from the summit is likely now varying within a typical range of 1,000 to 5,000 tonnes per day.
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.
Analysis:
Summit reinflation continues but was interrupted by two shifts to deflationary tilt, which pushed back the forecast window for episode 51. Vent glow has been continuous since the end of episode 50. Strong glow from both vents, and rare spattering in the north vent overnight, indicates that magma is near the surface. The current forecast suggests that episode 51 will occur sometime between July 11 and 13 if there are no additional deflationary events.
Kīlauea has been erupting episodically since December 23, 2024, from two vents (north and south) in Halema‘uma‘u. Lava fountaining episodes, which generally last for less than 12 hours, are separated by pauses that can be longer than three 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
Summary of episode 50:
A detailed account of episode 50 is given in the HVO Status Report issued on June 27: https://volcanoes.usgs.gov/hans-public/notice/DOI-USGS-HVO-2026-06-28T04:29:55+00:00
Tephra fall was restricted mostly to the closed area of Hawaiʻi Volcanoes National Park to the southwest of the active Halemaʻumaʻu vents. A light fall of Peleʻs hair was reported from the town of Pāhala in Kaʻū.
Resources:
NOTE: HVO’s monitoring network is mostly recovered from recent power- and storm-related outages. Several summit stations, including the SDH tiltmeter, will remain offline until we are able to re-establish access across the deep tephra field southwest of the caldera.
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 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.
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 INFORMATION STATEMENT
U.S. Geological Survey
Thursday, July 9, 2026, 9:30 PM HST (Friday, July 10, 2026, 07:30 UTC)
HAWAIIAN VOLCANO OBSERVATORY INFORMATION STATEMENT
On Thursday, July 9, 8:17 p.m. HST, a magnitude-4.5 earthquake occurred 34 mi (54 km) west-southwest of Captain Cook on the Island of Hawaiʻi at a depth of 24 mi (39 km) below sea level. The earthquake had no apparent impact on either Mauna Loa or Kīlauea volcanoes.
The depth and location of this earthquake indicate it is another lithospheric flexure earthquake related to bending of the ocean crust and upper brittle mantle (the lithosphere) by the weight of the islands. No impact to the ongoing eruption of Kīlauea volcano is expected.
The USGS Hawaiian Volcano Observatory continues to monitor Hawaiian volcanoes for any changes.
EARTHQUAKE DESCRIPTION
EARTHQUAKE INTENSITY AND AFFECTED AREA
EARTHQUAKE MAPS AND ADDITIONAL 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
NORTHERN MARIANA ISLANDS WEEKLY UPDATE
U.S. Geological Survey
Friday, July 10, 2026, 9:19 AM ChST (Thursday, July 9, 2026, 23:19 UTC)
Report prepared by the U.S. Geological Survey.
NORTHERN MARIANAS VOLCANOES
No signs of significant unrest were detected at any Northern Mariana Island volcanoes during the past week. There were signs in satellite data of weak underwater plumes at Ahyi Seamount, typical of ongoing activity in the area over recent months. Geophysical data streams were temporarily interrupted due to Typhoon Bavi, but have since been restored to pre Bavi levels.
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.
For definitions of Aviation Color Codes and Volcano Alert Levels: https://www.usgs.gov/programs/VHP/volcanic-alert-levels-characterize-conditions-us-volcanoes
SUBSCRIBE TO VOLCANO ALERT MESSAGES by email: http://volcanoes.usgs.gov/vns/
CNMI Homeland Security and Emergency Management
https://opd.gov.mp/library/agency/homeland-security-and-emergency-management.html
USGS Northern Mariana Duty Scientist (907) 786-7497
http://volcano.wr.usgs.gov/cnmistatus.php
Satellite information, Washington VAAC
http://www.ssd.noaa.gov/VAAC/washington.html