USGS Volcanoes: Notices released in the last day.

Slow eruption of lava within the summit crater continues. Minor earthquakes were detected over the past day, likely associated with rockfall on the growing dome. No activity was observed in cloudy satellite and webcam images over the past day.  

The current eruption began in July 2021. 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.

Low-level earthquake activity continued over the past day. No activity was observed in cloudy satellite and webcam images. 

A new temporary monitoring station was installed recently near Mount Kupreanof and is providing seismic data, infrasound data, gas measurements, and web camera images on an intermittent basis. This is by design to conserve battery power, but the frequency of data acquisition can be increased if activity warrants. The closest functioning seismometers that provide continuous data are approximately 10 miles (16 km) to the northeast 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.

Unrest continues with minor seismic and infrasound activity detected during the past day. No activity was observed in cloudy satellite and webcam images. Sulfur dioxide emissions were observed in satellite data.

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. 

Overview:

The summit eruption of Kīlauea in Halemaʻumaʻu is paused following 9.6 hours of lava fountaining during episode 53 on August 12-13, 2026. Inflationary tilt measured by tiltmeters around the summit of Kīlauea resumed after episode 53 ended, accompanied by continued glow from both vents, suggesting that another episode is likely. More data are needed to determine the forecast. 

No significant activity has been noted along Kīlauea’s East Rift Zone or Southwest Rift Zone.

A summary of episode 53 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 and occasional flames were visible overnight from the north vent in Halema’uma’u. Intermittent glow was also visible from the new west vent, but the south vent remained dark. Shifting incandescent spots were visible overnight from lava flows that erupted onto the floor of Halema'uma'u crater and the slopes of the active vents. Slow movements from cooling lava flows and gravity induced slumps on the vents are expected to continue in the coming days and nights. Strong trade winds are pushing the degassing plume to the southwest over the Kaʻū Desert this morning.

Low-frequency seismic pulsing began with the cessation of episode 53 and continues this morning, which is typical during the onset of pauses between eruptive episodes. Six shallow earthquakes have been recorded in the summit area in the past 24 hours. The largest was a magnitude-2.1 at 6:43 p.m. yesterday, near the south rim of Halemaʻumaʻu. 

Deflationary tilt measured at a summit tiltmeter at Uēkahuna (UWD) totaled 14.0 microradians during episode 53. Inflation resumed immediately upon cessation of fountains, and the UWD tiltmeter has since recovered 2.2 microradians of inflationary tilt.  

During inter-episode pauses, the sulfur dioxide (SO₂) emission rate from the summit typically varies between 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:

The abrupt switch from summit deflation to inflation at the end of episode 53 along with glow from the vents indicates that episode 54 fountaining is likely. More inflationary tilt data are needed to determine the forecast window.

Kīlauea has been erupting episodically since December 23, 2024, from two vents (north and south) in Halema‘uma‘u. A collapse pit in the slope behind the south vent formed a new west vent during episode 53. Lava fountaining episodes, which generally last for less than 12 hours, are separated by pauses of two or more 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 53:

A detailed account of episode 53 is given in the HVO Status Report issued on August 13: https://volcanoes.usgs.gov/hans-public/notice/DOI-USGS-HVO-2026-08-13T11:52:10+00:00

• Episode 53 of the ongoing Halemaʻumaʻu eruption began around 3:45 p.m. HST on August 12 and ended abruptly at 1:23 a.m. HST on August 13, 2026.
• The maximum lava fountain height was approximately 500 feet (150 meters) above ground level from the north vent. The south vent never fountained during this episode but did produce overflows prior to the fountaining episode. A new west vent produced precursory overflows and emitted intermittent flames through most of the eruption. 
• The maximum plume height was approximately 18,000 (5,500 meters) above mean sea level. 

• Tephra fall was restricted mostly to the closed area of Hawaiʻi Volcanoes National Park, southwest of the active Halemaʻumaʻu vents.  

   

Resources:

NOTE: HVO’s monitoring network is mostly recovered from recent power- and storm-related outages. Several summit stations will remain offline as we continue working to repair instruments and re-establish connections in our monitoring network.

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.

Activity Summary: 

• Episode 53 of the ongoing Halemaʻumaʻu eruption began around 3:45 p.m. HST August 12 and ended abruptly at 1:23 a.m. HST on August 13, 2026. 
• The maximum lava fountain height was approximately 500 feet (150 meters) above ground level from the north vent. The south vent never fountained during this episode. The new west vent (formerly the collapse pit) periodically emitted flames during the episode that were most visible after 7:00 p.m. HST.
• The maximum plume height was approximately 18,000 (5,500 meters) above mean sea level. 
• Tephra fall was restricted completely to the closed area of Hawaiʻi Volcanoes National Park to the southwest and west of the active Halemaʻumaʻu vents.   

Episode 53 Chronology: 

Lava fountain episode 53 in Halemaʻumaʻu at the summit of Kīlauea began around 3:45 p.m. HST August 12, 2026, and ended at 1:23 a.m. HST on August 13, 2026, after 9.6 hours of continuous fountaining from the north vent. The last four minutes were marked by gas jetting and flames from the north vent. The south vent never fountained during this episode but did overflow along with the new west vent (formerly the collapse pit) near the beginning of the episode. The new west vent (formerly the collapse pit) periodically emitted flames that were most visible after 7:00 p.m. HST. The instantaneous effusion rate peaked at about 300 cubic yards (230 cubic meters) per second at approximately 5:15 p.m. HST, with an average effusion rate of 180 cubic yards (135 cubic meters) per second for the entire fountaining episode. An estimated 6 million cubic yards (4.6 million cubic meters) of lava erupted and covered about 40-50% of the Halemaʻumaʻu crater floor. Seismicity followed the normal change in tremor patterns seen after most fountain episodes. The Uēkahuna tiltmeter (UWD) recorded about 14.0 microradians of deflationary tilt during episode 53. 

Fountain activity transitioned gradually from precursory lava flows from the north vent. Small glimpses of spatter were seen after 10:00 a.m. HST but spatter was not consistently visible until 11:04 a.m. HST. This was followed by a series of short-lived lava overflows that began at 11:20 a.m., 11:35 a.m., 11:45 a.m., and 12:23 p.m. HST, each lasting 1-4 minutes. A fifth sluggish flow began around 1:00 p.m. HST and became sustained, gradually growing for about 45 minutes.  At 1:45 p.m. HST, there was a dramatic increase in output correlated with a switch to deflationary tilt. A double dome fountain formed and began feeding a broad overflow that rapidly extended more than 2,000 feet (600 meters) from the vent. Large overflows from the south vent began at 3:26 p.m. and 3:38 p.m. HST and lasted approximately 5-6 minutes each. A small flow was also visible from the west vent (previously referred to as the new collapse feature) beginning at 3:31 p.m. HST.  This small flow lasted for 28 minutes and ended 14 minutes after the start of episode 53. Two more flows sourced from the south vent and the west vent began at 4:02 p.m. and 4:03 p.m. respectively. The flow from the south vent only lasted 3 minutes.  In contrast, the flow from the new west vent lasted 14 minutes and increased in intensity until it finally overflowed and drained into the south vent. There may have been other short periods of activity from the new west vent at 4:30 and 4:42 p.m. HST, but the view was obscured by the north vent fountains at that time.

The transition from precursory activity to the onset of episode 53 fountaining was marked by increasing height of the north vent dome fountain, greater eruptive volume, increased deflation and rapidly increasing tremor. The north vent lava fountain reached a peak height of approximately 500 feet (150 meters) around 5:00 p.m. HST and produced significant heat and ash, feeding a gas plume that reached a maximum height of about 18,000 feet (5,500 meters) above sea level based on webcam images and data reported by the National Weather Service (NWS).

Winds were out of the northeast below the inversion layer (about 10,000 feet or 3,000 meters above sea level) during fountaining, causing the plume to carry gas and fine ash/Peleʻs hair toward the southwest at lower levels. Higher level winds were more easterly and transported gas and fine tephra westward toward the summit of Mauna Loa. The plume track largely remained either within Hawaiʻi Volcanoes National Park or over unpopulated areas. Tephra larger than ash size (about 1/16 of an inch or 1 millimeter) was falling out of the plume within 0.5 - 1.2 miles (1-2 km) of the vents within the closed area of the National Park. 

By 6:40 p.m. HST on August 12, fountain heights decreased to about 350-400 feet (110-120 meters) above ground level, and plume heights decreased to 15,000 feet (4,500 meters) above sea level. Fountain heights remained mostly constant until about 9:00 p.m. HST when they began to slowly drop, reaching 330 feet (100 meters) just before 10:00 p.m. HST. The plume cloud heights also dropped to about 10,000 feet (3,000 meters) at the same time. By midnight, the fountain had dropped slightly to 300 feet (90 meters) high with little change in the altitude of the plume cloud.  The final fountains varied from about 100-200 feet (30-60 meters) high during the last half hour of the eruption, which ended abruptly at 1:23 a.m. HST on August 13.

The abrupt switch from summit deflation to inflation at the end of episode 53 indicates that another lava fountaining episode is likely. 

Published Notices about episode 53:  

Volcano Activity Notice at end of episode 53

Volcano Activity Notice for maximum episode 53 fountain heights. 

HVO short messages posted to the HVO website and social media as episode 53 progressed: HVO - Observatory Messages | U.S. Geological Survey 

Volcano Activity Notice when episode 53 began.

Volcano Activity Notice when precursory overflows prior to episode 53 began.

Kīlauea Daily Update for August 12, 2026.

Resources:

• Additional short messages during episodes: https://www.usgs.gov/observatories/hvo/observatory-messages   
• Timeline of eruptive episodes since December 23, 2024: https://www.usgs.gov/volcanoes/kilauea/science/eruption-information 
• Three Kīlauea summit livestream videos: https://www.youtube.com/@usgs/streams 
• Report tephra fall: https://hawaiiash.science/report_form 
• Hawaiʻi Volcanoes National Park Information https://www.nps.gov/havo/planyourvisit/conditions.htm
• County of Hawaii Hazard Impact Map: https://www.arcgis.com/apps/dashboards/5865229bcba74020992b372ef18b6f17

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 smog) 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 the links below:
  • https://seagrant.soest.hawaii.edu/resource-and-guidance-for-volcanic-tephra-fall/  
  • https://vog.ivhhn.org/sites/default/files/PelesHair_FAQs_v2.pdf
• 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.

Episode 53 of the ongoing Halemaʻumaʻu eruption ended abruptly at 1:23 a.m. HST on August 13 after 9.6 hours of continuous lava fountaining. Peak fountain heights reached approximately 500 ft (150 m) above ground level, and plume height reached over 18,000 ft (5500 m) above sea level. Additional details on this eruptive episode will be provided in the next official report.

• All eruptive vents and lava flows are confined to Halemaʻumaʻu crater within Hawaiʻi Volcanoes National Park. Tephra fall from volcanic ash clouds is greatest within 3 miles (5 km) of the vents, lighter ash and Pele's Hair may stay suspended for large distances from the vents.
• Timeline of eruptive episodes since December 23, 2024: https://www.usgs.gov/volcanoes/kilauea/science/eruption-information 
• Three Kīlauea summit livestream videos are available here: https://www.youtube.com/@usgs/streams 
• Additional short updates shared during the episode can be found here: https://www.usgs.gov/observatories/hvo/observatory-messages 

Episode 53 of lava fountaining in Halemaʻumaʻu at the summit of Kīlauea began at 3:45 p.m. HST on August 12 and continues as of this notice at 15:45 p.m. HST. 

Peak fountain heights have reached 500 ft (150 m) above ground level between 5:00 and 5:45 p.m. HST. The plume from this eruption is reaching over 18,000 feet above sea level. Ground-level sensors near the eruptive vents indicate that winds are blowing from the northeast carrying SO2 gas along with fine ash and Peleʻs hair to the southwest. Models, NWS data, and satellite images show the plume carrying gas and possibly fine ash and Peleʻs hair westward from the vent area.

• All eruptive vents and lava flows are confined to Halemaʻumaʻu crater within Hawaiʻi Volcanoes National Park. Tephra fall from volcanic ash clouds is greatest within 3 miles (5 km) of the vents, lighter ash and Pele's Hair may stay suspended for large distances from the vents.
• Help support science and community awareness by reporting tephra fall: https://hawaiiash.science/report_form 
• Three Kīlauea summit livestream videos that show eruptive lava fountains are available here: https://youtube.com/@usgs/streams 
• KPcam and MKcam provide views of the plume height for aviation purposes
• Additional short updates as the episode progresses will be posted here: https://www.usgs.gov/observatories/hvo/observatory-messages 
• Timeline of eruptive episodes since December 23, 2024: https://www.usgs.gov/volcanoes/kilauea/science/eruption-information 

Most lava fountaining episodes since December 23, 2024, have continued for a day or less.

Episode 53 of lava fountaining in Halemaʻumaʻu at the summit of Kīlauea began from the north vent at 3:45 p.m. HST on August 12, 2026. Fountaining is currently 80-100 ft (25-30 meters) high and expected to reach a maximum height in 1-2 hours. 

Fountain activity transitioned gradually from precursory lava flows from the north vent. Small glimpses of spatter were seen after 10:00 a.m. HST but spatter was not consistently visible until 11:04 a.m. HST. This was followed by a series of short-lived lava overflows that began at 11:20 a.m., 11:35 a.m., 11:45 a.m., and 12:23 p.m. HST, each lasting 1-4 minutes. A fifth sluggish flow began around 1:00 p.m. HST and became sustained, gradually growing for about 45 minutes.  At 1:45 p.m. HST, there was a dramatic increase in output correlated with a switch to deflationary tilt. A double dome fountain formed and began feeding a broad overflow that rapidly extended more than 2000 feet (600 meters) from the vent. Large overflows from the south vent began at 3:26 p.m. and 3:38 p.m. HST and lasted approximately 5-6 minute each. A small flow was also visible from the collapse crater behind the south vent beginning at 3:31 p.m. HST. 

Ground-level sensors near the eruptive vents indicate that winds are blowing from the northeast direction, which suggests that volcanic gas emissions and volcanic material may be distributed to the southwest direction from Halemaʻumaʻu. Winds above the inversion layer are more easterly and expected to carry tephra westward, if the fountains are high enough. The volcanic gas plume is currently 6,000 ft above ground level. 

• All eruptive vents and lava flows are confined to Halemaʻumaʻu crater within Hawaiʻi Volcanoes National Park. Tephra fall from volcanic ash clouds is greatest within 3 miles (5 km) of the vents, lighter ash and Pele's Hair may stay suspended for large distances from the vents.
• Support science and community awareness by reporting tephra fall: https://hawaiiash.science/report_form 
• Three Kīlauea summit livestream videos that show eruptive lava fountains are available here: https://youtube.com/@usgs/streams 
• KPcam and MKcam provide views of the plume height for aviation purposes
• Additional short updates as the episode progresses will be posted here: https://www.usgs.gov/observatories/hvo/observatory-messages 
• Timeline of eruptive episodes since December 23, 2024: https://www.usgs.gov/volcanoes/kilauea/science/eruption-information 

Most lava fountaining episodes since December 23, 2024, have continued for a day or less.

No activity was observed in occasional clear satellite images or distal geophysical monitoring data over the past week.

Eruptive activity at Ahyi Seamount may present a hazard to mariners in the water above and near the volcano. The summit has shallowed over the course of previous eruptions to 180 feet (55 m) below sea level, but the lack of local real-time data means we are unable to forecast or warn of impending eruptions. We will continue to monitor satellite and distal hydroacoustic data for additional evidence for, or escalation of, volcanic activity.

NORTHERN MARIANAS VOLCANOES
No signs of significant unrest were detected at any Northern Mariana Island volcanoes during the past week. 

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.