All times are local unless otherwise stated.

Kerinci | 27 April-3 May 2016 | New Activity / Unrest Cite this Report
Kerinci Central Sumatra	Based on a pilot observation, the Darwin VAAC reported that on 29 April an ash plume from Kerinci rose to an altitude of 6.1 km (20,000 ft) a.s.l. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Klyuchevskoy | 27 April-3 May 2016 | New Activity / Unrest Cite this Report
Klyuchevskoy Central Kamchatka (Russia)	KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 21-29 April. Satellite and video data showed a lava flow effusing on the SE flank, moving down the Apakhonchich drainage. Satellite images showed an intense thermal anomaly over the volcano, and an ash cloud that drifted about 500 km SW during 23-24 April. The Aviation Color Code was raised to Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Rincon de la Vieja | 27 April-3 May 2016 | New Activity / Unrest Cite this Report
Rincon de la Vieja Costa Rica	OVSICORI-UNA reported that a moderate hydrothermal explosion occurred at 1437 on 1 May in Rincón de la Vieja's crater lake. The seismic network recorded the explosion for 11 minutes. Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA)
Santa Maria | 27 April-3 May 2016 | New Activity / Unrest Cite this Report
Santa Maria Southwestern Guatemala	INSIVUMEH reported in a special notice posted on 2 May that strong explosive activity continued at Caliente cone, part of Santa María's Santiaguito lava-dome complex. Two pyroclastic flows, generated by strong explosions the previous day, traveled down E and W drainages. Collapses of the E and W edges of the crater generated a mushroom-shaped ash cloud that rose 7.6 km and drifted 40 km W and SW. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Whakaari/White Island | 27 April-3 May 2016 | New Activity / Unrest Cite this Report
Whakaari/White Island North Island (New Zealand)	GeoNet reported that an eruption at White Island at 2150 on 27 April was inferred by a combination of data that included the seismic network and a MetService rain radar image. The Volcanic Alert Level was raised from 1 to 3 (Minor Volcanic Eruption) and the Aviation Colour Code was raised from Green to Orange. Seismicity returned to normal levels shortly afterwards. During an overflight the next day volcanologists noted that ash deposits covered about 80% of the floor of Main Crater and continued up the N and S parts of the crater walls. Ash deposits were about 5 mm thick in areas 500 m away from the eruption site. Seismicity remained low and gas emission levels were similar to those measured prior to the event. The Volcanic Alert Level was lowered to 2. During an aerial inspection of the area on 29 April, volcanologists observed a new crater in the NE corner of the 1978/90 Crater Complex. Gas output was slightly elevated but within the range of measurements of long-term gas output. Analysis of the eruption deposits showed that no new lava was ejected, and was instead old strongly hydrothermally altered rock material. On 2 May the Aviation Colour Code was lowered to Yellow. Source: GeoNet

Alaid | 27 April-3 May 2016 | Continuing ActivityCite this Report
Alaid Kuril Islands (Russia)	KVERT reported that moderate activity at Alaid continued during 22-29 April. Satellite images showed an intense daily thermal anomaly over the volcano, and an ash plume that drifted 260 km SE on 21 and 23 April. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Bagana | 27 April-3 May 2016 | Continuing ActivityCite this Report
Bagana Bougainville (Papua New Guinea)	Based on analyses of satellite imagery and model data, the Darwin VAAC reported that during 27 April-3 May ash plumes from Bagana rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 45-100 km SW, W, and NW. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Cleveland | 27 April-3 May 2016 | Continuing ActivityCite this Report
Cleveland Chuginadak Island (USA)	On 29 April, AVO reported that no activity had been detected at Cleveland following the 16 April explosion; seismicity had returned to low levels within an hour of the event and no infrasound (pressure sensor) signals had been detected. Recent satellite images indicated that the August 2015 lava dome was gone and had been replaced with a small cinder cone within the summit crater. The Level of Concern Color Code was lowered to Yellow and the Volcano Alert Level was lowered to Advisory. Source: US Geological Survey Alaska Volcano Observatory (AVO)
Colima | 27 April-3 May 2016 | Continuing ActivityCite this Report
Colima Mexico	The Washington VAAC reported that a three-minute-long ash emission was recorded on 28 April by Colima's webcam. On 1 May ash puffs observed with the webcam and satellite images rose to an altitude of 4.6 km (15,000 ft) a.s.l. and drifted E. Based on information from Colima Towers and the Mexico City MWO, and webcam and satellite views, ash plumes rose to an altitude of 5.2 km (17,000 ft) a.s.l. and drifted NE during 2-3 May. Source: Washington Volcanic Ash Advisory Center (VAAC)
Karymsky | 27 April-3 May 2016 | Continuing ActivityCite this Report
Karymsky Eastern Kamchatka (Russia)	On 28 April KVERT reported that satellite images over Karymsky showed either cloud cover or quiet conditions at the volcano during March-April. Moderate gas-and-steam emissions continued. The Aviation Color Code was lowered to Yellow. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Kilauea | 27 April-3 May 2016 | Continuing ActivityCite this Report
Kilauea Hawaiian Islands (USA)	HVO reported that seismicity beneath Kilauea's summit, upper East Rift Zone, and Southwest Rift Zone was at background levels during 27 April-3 May. The lava lake continued to circulate and eject spatter in the Overlook vent. Webcams recorded outgassing from multiple spatter cones on the Pu'u 'O'o Crater floor. A small lava flow from the E vent flowed onto the crater floor during 28 April-1 May. The June 27th NE-trending lava flow continued to be active within 5.7 km NE of Pu'u 'O'o Crater. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Masaya | 27 April-3 May 2016 | Continuing ActivityCite this Report
Masaya Nicaragua	INETER reported that during 27 April-3 May gas emissions at Masaya's Santiago crater were at low-to-moderate levels. Seismic tremor decreased though continued to fluctuate between low to moderate levels. The lava lake continued to strongly circulate. Source: Instituto Nicaragüense de Estudios Territoriales (INETER)
Nevado del Ruiz | 27 April-3 May 2016 | Continuing ActivityCite this Report
Nevado del Ruiz Colombia	Based on a SGC notice, the Washington VAAC reported that on 2 May an ash emission from Nevado del Ruiz rose to an altitude of 7 km (23,000 ft) a.s.l. and drifted NW. Source: Washington Volcanic Ash Advisory Center (VAAC)
Sangay | 27 April-3 May 2016 | Continuing ActivityCite this Report
Sangay Ecuador	Based on satellite images and notices from the Guayaquil MWO, the Washington VAAC reported that during 27 April-3 May ash plumes from Sangay rose to altitudes of 5.8-7 km (19,000-23,000 ft) a.s.l. and drifted as far as 120 km WNW, W, and S. A thermal anomaly was identified in satellite images during 29-30 April and on 2 May. Source: Washington Volcanic Ash Advisory Center (VAAC)
Sheveluch | 27 April-3 May 2016 | Continuing ActivityCite this Report
Sheveluch Central Kamchatka (Russia)	KVERT reported that during 21-29 April lava-dome extrusion onto Sheveluch’s N flank was accompanied by strong fumarolic activity, dome incandescence, ash explosions, and hot avalanches. Satellite images showed an intense daily thermal anomaly over the dome. The Aviation Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Sinabung | 27 April-3 May 2016 | Continuing ActivityCite this Report
Sinabung Northwestern Sumatra	Based on satellite images and information from PVMBG, the Darwin VAAC reported that during 28-30 April and 4 May ash plumes from Sinabung rose to altitudes of 3.6-4.2 km (12,000-14,000 ft) a.s.l. and drifted W and WSW. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Tengger Caldera | 27 April-3 May 2016 | Continuing ActivityCite this Report
Tengger Caldera Eastern Java	Based on satellite images and wind data, the Darwin VAAC reported that during 27-28 April ash plumes from Tengger Caldera's Bromo cone rose to altitudes of 3-3.6 km (10,000-12,000 ft) a.s.l. and drifted NW, W, SW, and SE. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Turrialba | 27 April-3 May 2016 | Continuing ActivityCite this Report
Turrialba Costa Rica	OVSICORI-UNA reported that at about 0530 on 28 April seismicity at Turrialba increased, though gas-and-steam emissions continued at normal levels. At 0300 on 30 April passive ash emissions began and rose over 500 m above West Crater. Continuous variable amplitude tremor and frequent small explosions were recorded during 30 April-1 May. At 0630 on 1 May residents in Santa Cruz de Turrialba (8 km SSE) reported hearing sounds from the volcano resembling a turbine. At the same time the seismic network recorded an increase in the amplitude of tremor, associated with an increase in gas and tephra emissions. Minor amounts of ash fell in La Central (4 km SW) and La Pastora. On 2 May frequent small explosions and sustained seismic tremor with significantly variable amplitude were recorded. Ash-and-gas emissions rose 500 m above the crater and drifted W, though periodically plumes with higher volumes of ash rose just over 1 km. Based on a news report, there were more than 200 explosions recorded during 29 April-2 May; an explosion at around 0600 on 2 May produced an ash plume that rose 2 km high. Seismic amplitude began decreasing during 0300-0700 on 3 May. Frequent explosions continued to produce ash plumes that rose as high as 1 km and drifted mainly N. Most tephra-fall occurred around West and Central craters. Sources: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA), Tico Times

Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 20,019 individual reports over 1,216 weeks (average of 16 per week) on 332 different volcanoes.

Use the dropdowns to choose the year and week for archived Weekly Reports.

 News Feeds and Google Placemarks

 Criteria & Disclaimers

The Weekly Volcanic Activity Report does not necessarily include all volcanic activity that occurred on Earth during the week. More than a dozen volcanoes globally have displayed more-or-less continuous eruptive activity for decades or longer, and such routine activity is typically not reported here. Moreover, Earth's sea-floor volcanism is seldom reported even though in theory it represents the single most prolific source of erupted material. The Weekly Volcanic Activity Report summarizes volcanic activity that meets one or more of the following criteria:

- A volcano observatory raises or lowers the alert level at the volcano.
- A volcanic ash advisory has been released by a volcanic ash advisory center (VAAC) stating that an ash cloud has been produced from the volcano.
- A verifiable news report of new activity or a change in activity at the volcano has been issued.
- Observers have reported a significant change in volcanic activity. Such activity can include, but is not restricted to, pyroclastic flows, lahars, lava flows, dome collapse, or increased unrest.

Volcanoes are included in the "New Activity/Unrest" section of the Weekly Volcanic Activity Report if the activity occurs after at least 3 months of quiescence. Once a volcano is included in the "New Activity/Unrest" section, updates will remain in that section unless the activity continues for more than 1 month without escalating, after which time updates will be listed in the "Continuing Activity" section. Volcanoes are also included in the "New Activity/Unrest" section if the volcano is undergoing a period of relatively high unrest, or increasing unrest. This is commonly equal to Alert Level Orange on a scale of Green, Yellow, Orange, Red, where Red is the highest alert. Or alert level 3 on a scale of 1-4 or 1-5.

It is important to note that volcanic activity meeting one or more of these criteria may occur during the week, but may not be included in the Weekly Volcanic Activity Report because we did not receive a report.

1. The Weekly Volcanic Activity Report is intended to provide timely information about global volcanism on a weekly basis. Consequently, the report is generated rapidly by summarizing volcanic reports from various sources, with little time for fact checking. The accuracy of the Weekly Volcanic Activity Report is dependent upon the quality of the volcanic activity reports we receive. Reports published in the Bulletin of the Global Volcanism Network are cover longer time periods and are more carefully reviewed, although all of the volcanoes discussed in the Weekly Volcanic Activity Report are not necessarily reported in the Bulletin. Because of our emphasis on rapid reporting on the web we have avoided diacritical marks. Reports are updated on the Weekly Volcanic Activity Report web page as they are received, therefore information may be included regarding events that occurred before the current report period.

2. Rapidly developing events lead to coverage that is often fragmentary. Volcanoes, their eruptions, and their plumes and associated atmospheric effects are complex phenomena that may require months to years of data analysis in order to create a comprehensive summary and interpretation of events.

3. Preliminary accounts sometimes contain exaggerations and "false alarms," and accordingly, this report may include some events ultimately found to be erroneous or misleading.

4. Many news agencies do not archive the articles they post on the Internet, and therefore the links to some sources may not be active. To obtain information about the cited articles that are no longer available on the Internet contact the source.

5. USGS Disclaimer Statement for this Website:

Information presented on this website is considered public information and may be distributed or copied. Use of appropriate byline/photo/image credit is requested. We strongly recommend that USGS data be acquired directly from a USGS server and not through other sources that may change the data in some way. While USGS makes every effort to provide accurate and complete information, various data such as names, telephone numbers, etc. may change prior to updating. USGS welcomes suggestions on how to improve our home page and correct errors. USGS provides no warranty, expressed or implied, as to the accuracy, reliability or completeness of furnished data.

Some of the documents on this server may contain live references (or pointers) to information created and maintained by other organizations. Please note that USGS does not control and cannot guarantee the relevance, timeliness, or accuracy of these outside materials.

For site security purposes and to ensure that this service remains available to all users, this government computer system employs software programs to monitor network traffic to identify unauthorized attempts to upload or change information, or otherwise cause damage. Unauthorized attempts to upload information or change information on this website are strictly prohibited and may be punishable under the Computer Fraud and Abuse Act of 1986 and the National Information Infrastructure Protection Act. Information may also be used for authorized law enforcement investigations. (Last modified September 21, 1999.)

U.S. Department of the Interior, U.S. Geological Survey, Reston, VA, USA
URL: https://volcano.si.edu/reports_weekly.cfm

 Acronyms and Abbreviations

a.s.l. - above sea level

AVO - Alaska Volcano Observatory

AVHRR - Advanced Very High Resolution Radiometer

CENAPRED - Centro Nacionale de Prevencion de Desastres (México)

CONRED - Coordinadora Nacional para la Reducción de Desastres

COSPEC - Correlation Spectrometer

CVGHM (formerly VSI) - Center of Volcanology and Geological Hazard Mitigation

CVO - Cascades Volcano Observatory (USGS)

GMS - Geostationary Meteorological Satellite

GOES - Geostationary Operational Environmental Satellite

GVO - Goma Volcano Observatory

GVP - Global Volcanism Program (Smithsonian Institution)

HVO - Hawaiian Volcano Observatory (USGS)

ICE - Instituto Costarricense de Electricidad (Costa Rica)

IG - Instituto Geofísico (Ecuador)

IGNS - Institute of Geological and Nuclear Sciences (New Zealand) - now GNS Science

INETER - Instituto Nicaragüense de Estudios Territoriales (Nicaragua)

INGEMMET - Instituto Geológical Minero y Metalúrgico (Peru)

INGEOMINAS - Instituto Colombiano de Geología y Minería (Colombia)

INGV-CT - Istituto Nazionale di Geofisica e Vulcanologia - Sezione di Catania (Italy)

INSIVUMEH - Instituto Nacional de Sismologia, Vulcanologia, Meteorologia e Hidrologia (Guatemala)

IRD - Institut de Recherche pour le Développement (France)

JMA - Japanese Meteorological Agency

KEMSD - Kamchatkan Experimental and Methodical Seismilogical Department

KVERT - Kamchatkan Volcanic Eruption Response Team

M - magnitude

METEOSAT - Meteorological Satellite

MEVO - Mount Erebus Volcano Observatory

MODIS - Moderate Resolution Imaging Spectroradiometer

MVO - Montserrat Volcano Observatory

MWO - Meteorological Watch Office

NEIC - National Earthquake Information Center

NIED - National Research Institute for Earth Science and Disaster Prevention (Japan)

NOAA - National Oceanic and Atmospheric Administration

NOTAM - Notice to Airmen

OVDAS - Observatorio Volcanologico de los Andes del Sur (Chile)

OFDA - Office of US Foreign Disaster Assistance

ONEMI - Oficina Nacional de Emergencia - Ministerio del Interior (Chile)

OVPDLF - Observatoire Volcanologique du Piton de la Fournaise (France)

OVSICORI-UNA - Observatorio Vulcanologico y Sismologico de Costa Rica, Universidad Nacional (Costa Rica)

PHIVOLCS - Philippine Institute of Volcanology and Seismology (Philippines)

RSAM - Real-time Seismic Amplitude Measurement

RVO - Rabaul Volcano Observatory

SERNAGEOMIN - Servicio Nacional de Geologia y Mineria (Chile)

SIGMET - Significant Meteorological Information

SNET - Servicio Nacional de Estudios Territoriales (El Salvador)

SVERT - Sakhalin Volcanic Eruption Response Team (Russia)

USAID - US Agency for International Development

USGS - United States Geological Survey

UTC - Coordinated Universal Time

VAAC - Volcanic Ash Advisory Center

VAFTAD - Volcanic Ash Forecast Transport And Dispersion

VDAP - Volcano Disaster Assistance Program (USGS)

VHP - Volcano Hazards Program (USGS)

VRC - Volcano Research Center (Japan)