USGS Volcanoes: Notices released in the last day.

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. 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.

Earthquake activity continues near Mount Kupreanof volcano, with magnitudes mostly under 2.0 this week. The two largest earthquakes had magnitudes of 2.0 and 2.3 and occured on June 27. Sulfur dioxide gas emissions were detected in satellite images on June 27 and 29. 

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. 

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 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.

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. Early on July 3, sensors recorded a minor debris flow in Tahoma Creek at Mount Rainier. Although the flow has not yet been confirmed by observers on the ground, we infer that it resulted from a glacial outburst originating from the South Tahoma Glacier, based on its similarity to signals from debris flows in 2023 and 2025. It is likely that the debris flow did not reach the Nisqually River. In addition, scientists were in the field this week conducting geologic investigations at Glacier Peak.

Overview:

The summit eruption of Kīlauea in Halemaʻumaʻu is paused. Overnight webcam views showed glow at both the north and south eruptive vents. Summit inflation returned last night, and it continues at this time. Current forecast models suggest that lava fountaining episode 51 will occur sometime between July 9 and 15. 

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:

Moderate to bright glow was continuously visible from the south vent overnight, while weak glow was intermittently visible from the north vent. Subsidence of a localized area on the western Halemaʻumaʻu crater floor, observed for several days following lava fountaining episode 50, appears to have slowed.

Strong tremor bursts continue every 5–15 minutes. Earthquake activity beneath Kaluapele (Kīlauea caldera) remains low. 

Summit inflation returned last night, with tilt recovery presently at 5.6 microradians on the Uēkahuna (UWD) tiltmeter and gradually climbing. Kīlauea summit deflation totaled 15.3 microradians on UWD during lava fountaining 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:

Tiltmeters began tracking summit reinflation immediately after the end of lava fountaining episode 50, but it transitioned to slow deflation on Tuesday, June 30 that lasted for three days. The summit began inflating again late yesterday evening, July 2, and it continues at this time. Vent glow has been continuous since the end of episode 50 and another lava fountaining episode is likely. The current forecast suggests that episode 51 will occur sometime between July 9 and 15, but further periods of slowed inflation or even deflation may delay the onset of the episode.

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

• Episode 50 of the ongoing Halemaʻumaʻu eruption at the summit of Kīlauea ended abruptly at 5:10 p.m. HST on June 27, 2026, after 7 hours of continuous lava fountaining from the north vent. The eruption is currently paused.

• 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:

• 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 lava fountains and eruptive activity can be found here: https://www.usgs.gov/observatories/hvo/observatory-messages
• Three Kīlauea summit livestream cameras 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 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/
• Lava flows: lava on the floor of Halemaʻumaʻu crater and the southwest side of Kaluapele, Kīlauea's summit caldera, remains hot and may slowly move in the days immediately following an eruptive episode.

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.