ALASKA VOLCANO OBSERVATORY DAILY UPDATE
U.S. Geological Survey
Saturday, May 30, 2026, 12:00 PM AKDT (Saturday, May 30, 2026, 20:00 UTC)
Slow eruption of lava continues. Minor seismicity detected over the past day. Slightly elevated surface temperatures were observed in satellite data. Nothing was evident in web camera observations of the volcano.
The current eruption began in July 2021 and, 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.
To view monitoring data and other information about Great Sitkin Volcano: https://avo.alaska.edu/volcano/great-sitkin
Seismic activity was detected during the past day. Cloud cover prevented clear satellite views of the volcano. Sulfur dioxide emissions were detected in TROPOMI satellite data.
There is no real-time geophysical monitoring network at Mount Kupreanof. The closest functioning seismometers are 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, remote infrasound and lightning networks, and visual observations from pilots and mariners passing by the volcano.
To view monitoring data and other information about Mount Kupreanof: https://avo.alaska.edu/volcano/kupreanof
Minor seismic activity and infrasound were detected at the volcano. Sulfur dioxide emissions drifting to the northwest were evident in satellite imagery. Nothing was observed in cloudy satellite and web camera 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.
To view monitoring data and other information about Shishaldin Volcano: https://avo.alaska.edu/volcano/shishaldin
Matt Loewen, Acting Scientist-in-Charge, USGS mloewen@usgs.gov (907) 786-7036
David Fee, Coordinating Scientist, dfee1@alaska.edu UAFGI (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.
HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
U.S. Geological Survey
Sunday, May 31, 2026, 8:06 AM HST (Sunday, May 31, 2026, 18:06 UTC)
Overview:
There have been 29 precursory eruptions of sluggish lava from the south vent within Halemaʻumaʻu since they began at 5:41 p.m. HST on May 30. Spattering continues from the north vent, but no overflows at this time. The forecast for the onset of episode 48 fountaining is between today and tomorrow (May 31-June 1), with today more likely. There is potential for ashfall into surrounding communities from this episode; see below.
No significant activity has been noted along Kīlauea’s East Rift Zone or Southwest Rift Zone.
NOTE: The National Weather Service (NWS) has issued a Special Weather Statement regarding the potential for ash fall to the SW and NE of the summit of Kīlauea volcano. The statement can be found here: WWA Summary by Location for 19.69N 155.5W with HIZ027/HIC001/HIZ342 emphasis Special Weather Statem…
NOTE: Hawaii County Civil Defense Agency (HCCDA) has issued a message about the potential for ashfall alerting residents to prepare by closing windows and protecting catchment water supplies: https://evb.gg/n#lyhnndpyubk/0kFQoa2q
NOTE: Significant changes in activity between Daily Updates are posted here: https://www.usgs.gov/observatories/hvo/observatory-messages
Summit Observations:
Precursory overflows of degassed lava began from the south vent at 5:41 p.m. HST yesterday May 30. The overflows are generally small and stay within a few hundred meters of the vent. There have been 29 overflows so far that typically last 5-10 minutes and are spaced 15-30 minutes apart. Low dome fountains (5-10 ft or 1-3 m high) feed the passive overflows. The end of events is marked by vigorous drainback of lava and a drop in lava level within the vents. Spattering continued throughout the night building the small cone within the north vent. The vigor of spattering within the north vent greatly increased around 7:51 a.m. HST this morning (May 31) and lava appears to be coming out of the back wall vent and draining into the main vent. No precursory overflows have occurred from the north vent.
Seismic tremor continues but changed to well -efined gas pistoning with the first overflow. Low tremor characterizes the overflow followed by a sharp increase associated with drainback of lava. Earthquake activity beneath Kīlauea summit remains low with 6 earthquakes located around Halemaʻumaʻu in the last 24 hours. The largest was a magnitude 1.83 at 6:53 a.m. HST today (May 31) in the center of Halemaʻumaʻu.
Kīlauea summit inflation continues very slowly this morning, after flattening out with the onset of the first overflow. Since the end of lava fountaining episode 47 on May 15, the Uēkahuna tiltmeter (UWD) has tracked about 17 microradians of inflationary tilt (a small tilt offset was due to the M6 earthquake on the west side of the island on Friday evening). This instrument recorded 15.6 microradians of deflationary tilt during episode 47.
With the eruption now paused, 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. Measurements on Friday, May 22, indicated emission rates of about 2,000 tonnes per day. Surface winds are out of the northeast at the summit this morning with higher level winds forecast out of the west southwest. See the NWS Special Weather Service message linked at the top of this message.
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:
The rapid return of inflationary tilt and glow from both Halemaʻumaʻu eruptive vents indicates that another lava fountaining episode is likely. Lava spattering and overflows from one or both of the eruptive vents are expected to precede the next lava fountaining episode. Forecast models based on summit tilt are no longer valid. Seismic velocity models indicate that episode 48 fountains are most likely between this afternoon and Monday (May 31-June 1). The forecast window may change as more data are incorporated into the models or additional events occur.
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
Recap of episode 47:
Episode 47 ended abruptly at 12:27 a.m. HST on May 15 after 9 hours of continuous lava fountaining from the north vent. The eruptive plume sent light tephra into public areas of Hawai'i Volcanoes National Park and surrounding communities to the northeast. UWD tiltmeter recorded 15.6 microradians of deflation during the episode.
A full summary of episode 47 can be found in a Status Report here: https://volcanoes.usgs.gov/hans-public/notice/DOI-USGS-HVO-2026-05-15T10:42:06+00:00
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
Precursory low-level activity for episode 48 of the ongoing Halemaʻumaʻu eruption at the summit of Kīlauea began around 5:41 p.m. HST on May 30 with lava overflows from the south vent. Accordingly, HVO is raising the Alert Level for Kīlauea from ADVISORY to WATCH and the Aviation Color Code from YELLOW to ORANGE. Alert level and aviation color code definitions: https://www.usgs.gov/programs/VHP/alert-level-system. This low-level precursory activity can continue for hours to days before the lava fountaining episode beings. The forecast for episode 48 of lava fountaining to start is between May 30 and June 1. Another VAN will be published when lava fountaining episode 48 begins.
Most lava fountaining episodes since December 23, 2024, have continued for a day or less.
Hazard Analysis:
Volcanic Gas: water vapor (H2O), carbon dioxide (CO2), and sulfur dioxide (SO2) are continuously released during an eruption. SO2 reacts in the atmosphere to create the visible haze known as vog (volcanic air pollution) downwind, which may cause respiratory and other problems. 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: 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 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.
HVO continues to closely monitor Kīlauea and will issue additional notices as needed based on activity. Regularly scheduled daily updates for Kīlauea are posted on the HVO website at https://www.usgs.gov/volcanoes/kilauea/volcano-updates
More Information:
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
WMPA01 PHVO 310349
VONA
DTG: 20260531/0349Z
VOLCANO: KILAUEA 332010
PSN: N1925 W15517
AREA: HAWAII
SOURCE ELEV: 4091FT AMSL
NOTICE NR: 2026/32
CURRENT COLOUR CODE: ORANGE
PREVIOUS COLOUR CODE: YELLOW
SVO: HAWAIIAN VOLCANO OBSERVATORY
ACT STS: ERUPTION ONGOING
ONSET: NIL
DUR: NIL
VA CLD HGT: UNKNOWN
HGT SOURCE: WEBCAM
MOV: NO VA CLD PRODUCED
CTC: HVO DUTY SCIENTIST: 808-785-3144
RMK: LOW-LEVEL ERUPTION OF LAVA BEGAN AT THE SUMMIT OF KILAUEA AT 5:41 PM ON MAY 30 2026.
LOW-LEVEL ACTIVITY CAN PERSIST FOR HOURS TO DAYS BEFORE THE LAVA FOUNTAIN EPISODE
BEGINS. LAVA FOUNTAIN EPISODE 48 IS FORECAST TO START BETWEEN MAY 30-JUNE 1.
NXT NOTICE: A NEW VONA WILL BE ISSUED IF COND CHANGE SIGNIFICANTLY OR IF THE COLOR CODE CHANGES
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