USGS Volcano Notice - DOI-USGS-HVO-2025-06-28T00:57:23+00:00

Activity Summary:

Around 7:27 a.m. this morning, June 28, low-level precursory activity for summit eruption episode 27 began with lava overflows from the north vent, which continue intermittently at this time. Recent lava fountaining episodes during the ongoing eruption within Halemaʻumaʻu have been preceded by similar precursory activity that lasted from a few hours to a few days. Based on continued summit inflation, sustained lava fountaining is likely to begin on June 29 or 30 (tomorrow or Monday), but could begin sooner if precursory activity escalates. This window is subject to change due to variations in the inflation rate and other factors, and it will be refined as more data become available.

Episode 26 ended on June 20. Fountaining episodes have occurred approximately once per week since the start of the eruption on December 23, 2024. All eruptive activity remains within Hawaiʻi Volcanoes National Park, and no significant activity has been noted along Kīlauea’s East Rift Zone or Southwest Rift Zone. Current hazards include ongoing volcanic gas emissions, as well as windblown volcanic glass (Pele’s hair) and tephra deposited during past episodes in the Kīlauea summit region of Hawaiʻi Volcanoes National Park and nearby communities.

Summit Observations:

Lava spattering and jetting was intermittently visible in the north vent throughout last night. A lava pond within the north vent first appeared in webcam views around 5:00 a.m. this morning, with cycles of rising and falling eventually resulting in the first overflows around 7:27 a.m.

Episode 26 began at approximately 1:40 a.m. on June 20 and ended at 10:25 a.m. on June 20. Lava fountains from the north vent reached heights of up to about 1,250 feet (380 meters) during episode 26, a new fountain height record for this eruption. 

The tiltmeter near Uēkahuna (UWD) has recorded 15.5 microradians of inflationary tilt since the end of episode 26, after recording 18.5 microradians of deflationary tilt during episode 26. Seismic tremor continues at slightly elevated levels beneath Halemaʻumaʻu crater.

Vigorous degassing also continues from both the north and south vents. The average Sulfur dioxide (SO₂) emission rate between fountaining episodes is typically around 1,200 tonnes/day.

Strands of volcanic glass known as Pele’s hair are present throughout the summit area of Hawaiʻi Volcanoes National Park and surrounding communities and can be remobilized by wind.

• 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 
• Three Kīlauea summit livestream videos are available here: Kīlauea Volcano, Hawaii (West Halemaʻumaʻu crater) v1cam, Kīlauea Volcano, Hawaii (East Halemaʻumaʻu crater) v2cam, and Kīlauea volcano, Hawaii (South Halemaʻumaʻu crater) v3 cam
• Summit eruption webcams: https://www.usgs.gov/volcanoes/kilauea/summit-webcams 

The KW webcam was restored June 24, along with the laser rangefinder instrument that measures the surface of the lava lake. KW cam images are once again available online at https://www.usgs.gov/media/webcams/kwcam-halemaumau-and-down-dropped-caldera-floor-west-rim-summit-caldera-looking. On June 27, the F1 thermal webcam and B1 webcam were also restored, with their respective images available at https://www.usgs.gov/volcanoes/kilauea/f1cam-halemaumau-thermal-image-west-rim-summit-caldera-looking-southeast and https://www.usgs.gov/volcanoes/kilauea/b1cam-kilauea-caldera-down-dropped-block-and-halemaumau.

Rift Zone Observations:

Rates of seismicity and ground deformation remain very low in the East Rift Zone and Southwest Rift Zone, with no significant earthquake activity in the past 24 hours. Sulfur dioxide (SO₂) emissions from the East Rift Zone remain below the detection limit.

Analysis: 

The updated forecast window for the start of episode 27 lava fountaining is between June 29 and 30 (tomorrow or Monday) based on the current rate of summit inflation, but high fountains could begin sooner if precursory activity escalates. This window is subject to change due to variations in the summit inflation rate and other factors, and it will be refined as more data become available. In the lead-up to previous fountaining episodes, low-level precursory activity—like the currently observed overflows from the north vent, as well as lava spattering—lasted for hours to days before rapidly escalating into sustained high fountaining over minutes to tens of minutes.

The current eruption has been characterized by episodic lava fountaining not seen in any eruptions since the 1983–86 episodic fountains at the beginning of the Puʻuʻōʻō eruption. Lava fountains and flows have erupted from two vents within Halema'um'a'u crater that we refer to as the north vent and south vent. Each of the previous fountaining episodes lasted from a few hours to over a week and was accompanied by strong deflation of the summit region. Pauses between the fountaining episodes have been marked by an immediate change from deflation to inflation as the magma chamber recharges and repressurizes. Fountaining episodes have occurred approximately once per week since the start of the eruption. 

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.

Hazards: 

This episodic eruption is occurring within a closed area of Hawaiʻi Volcanoes National Park. High levels of volcanic gas—primarily water vapor (H₂O), carbon dioxide (CO₂), and sulfur dioxide (SO₂)—are the primary 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/

Additional hazards include Pele's hair and other volcanic fragments from lava fountains. Pele's hair is strands of volcanic glass often produced by lava fountaining activity. Volcanic fragments can fall on the ground within a few hundred yards (meters) of the eruptive vent(s), or downwind of the vent(s). Strong winds may waft light particles, including Pele's hair, to greater distances downwind. Once they are 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 current wind conditions. Residents and visitors should minimize exposure to Pele's hair and other volcanic fragments, which can cause skin and eye irritation. More information about how Pele's hair forms, 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.

For discussion of Kīlauea hazards, please see: https://www.usgs.gov/observatories/hawaiian-volcano-observatory/hazards.