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Smithsonian / USGS Weekly Volcanic Activity Report

Weekly Volcanic Activity Map

The Weekly Volcanic Activity Report is a cooperative project between the Smithsonian's Global Volcanism Program and the US Geological Survey's Volcano Hazards Program. Updated by 2300 UTC every Wednesday and averaging 16 reported volcanoes, this is not a comprehensive list of all eruptions this week, but rather a summary of activity that meet criteria discussed in the "Criteria and Disclaimers" section below.

Volcanic activity reported here is preliminary and subject to change. Carefully reviewed, detailed narratives over longer time periods are published as reports of the Bulletin of the Global Volcanism Network available through volcano profile pages.

Smithsonian / USGS Weekly Volcanic Activity Report for the week of 24 April-30 April 2013
Name Location Eruption Start Date Report Status
Antuco Central Chile New
Tungurahua Ecuador New
Aira Kyushu (Japan) 2017 Mar 25 Continuing
Batu Tara Komba Island Continuing
Chirpoi Kuril Islands (Russia) Continuing
Etna Sicily (Italy) 2022 Nov 27 Continuing
Fuego South-Central Guatemala 2002 Jan 4 Continuing
Gaua Banks Islands (Vanuatu) Continuing
Kilauea Hawaiian Islands (USA) Continuing
Kizimen Eastern Kamchatka (Russia) Continuing
Manam Northeast of New Guinea 2014 Jun 29 Continuing
Pacaya South-Central Guatemala Continuing
Paluweh N of Flores Island Continuing
Popocatepetl Mexico 2005 Jan 9 Continuing
Rabaul New Britain (Papua New Guinea) Continuing
Sangay Ecuador 2019 Mar 26 Continuing
Santa Maria Southwestern Guatemala 1922 Jun 22 Continuing
Sheveluch Central Kamchatka (Russia) 1999 Aug 15 Continuing
Soufriere Hills Montserrat Continuing
Tolbachik Central Kamchatka (Russia) Continuing
Whakaari/White Island North Island (New Zealand) Continuing
All times are local unless otherwise stated.
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.

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Agung Cuicocha Iliwerung Llaima Popocatepetl Sumbing
Ahyi Cumbal Inielika Lokon-Empung Purace Sundoro
Aira Dabbahu Ioto Lonquimay Puyehue-Cordon Caulle Suretamatai
Akan Davidof Irazu Lopevi Rabaul Suwanosejima
Alaid Dempo Iya Machin Raikoke Taal
Alu-Dalafilla Descabezado Grande Izu-Torishima Makushin Ranakah Tair, Jebel at
Ambae Dieng Volcanic Complex Jackson Segment Maly Semyachik Raoul Island Takawangha
Ambang Dukono Kaba Manam Rasshua Talang
Ambrym East Epi Kadovar Manda Hararo Raung Tambora
Anatahan Ebeko Kaitoku Seamount Marapi Redoubt Tanaga
Aniakchak Ebulobo Kama'ehuakanaloa Maroa Reventador Tandikat-Singgalang
Antillanca Volcanic Complex Edgecumbe Kambalny Martin Reykjanes Tangkoko-Duasudara
Antuco Egon Kanaga Masaya Rincon de la Vieja Tangkuban Parahu
Apoyeque Ekarma Kanlaon Maule, Laguna del Rinjani Tara, Batu
Arenal Eldey Karangetang Mauna Loa Ritter Island Ta'u
Asamayama Erebus Karkar Mayon Rotorua Taupo
Askja Erta Ale Karthala McDonald Islands Ruang Telica
Asosan Etna Karymsky Melebingoy Ruapehu Tenerife
Atka Volcanic Complex Etorofu-Yakeyama [Grozny Group] Kasatochi Melimoyu Ruby Tengger Caldera
Augustine Eyjafjallajokull Katla Merapi Ruiz, Nevado del Three Sisters
Avachinsky Fagradalsfjall Katmai Midagahara Sabancaya Tinakula
Awu Fernandina Kavachi Misti, El Sakar Tofua
Axial Seamount Fogo Kelimutu Miyakejima Salak Tokachidake
Azul, Cerro Fonualei Kelud Momotombo San Cristobal Tolbachik
Azumayama Fournaise, Piton de la Kerinci Monowai San Miguel Toliman
Bagana Fourpeaked Ketoi Montagu Island San Vicente Tongariro
Balbi Fuego Kharimkotan Moyorodake [Medvezhia] Sangay Trident
Bamus Fujisan Kick 'em Jenny Mutnovsky Sangeang Api Tungurahua
Banda Api Fukutoku-Oka-no-Ba Kie Besi Myojinsho Santa Ana Turrialba
Bardarbunga Galeras Kikai Nabro Santa Maria Ubinas
Barren Island Galunggung Kilauea Negra, Sierra Sao Jorge Ugashik-Peulik
Batur Gamalama Kirishimayama Negro, Cerro Sarigan Ukinrek Maars
Bezymianny Gamkonora Kita-Ioto Nightingale Island Sarychev Peak Ulawun
Bogoslof Gareloi Kizimen Nishinoshima Saunders Unnamed
Brava Gaua Klyuchevskoy Nisyros Savo Unnamed
Bristol Island Gorely Kolokol Group Novarupta Semeru Veniaminof
Bulusan Great Sitkin Koryaksky NW Rota-1 Semisopochnoi Villarrica
Calbuco Grimsvotn Krakatau Nyamulagira Seulawah Agam Vulcano
Callaqui Guagua Pichincha Krummel-Garbuna-Welcker Nyiragongo Sheveluch West Mata
Cameroon Guallatiri Krysuvik-Trolladyngja Ofu-Olosega Shishaldin Westdahl
Campi Flegrei del Mar di Sicilia Guntur Kuchinoerabujima Okataina Simbo Whakaari/White Island
Cayambe Hachijojima Kurikomayama Okmok Sinabung Witori
Chachadake [Tiatia] Hakoneyama Kusatsu-Shiranesan Ontakesan Sinarka Wolf
Chaiten Heard Kverkfjoll Oraefajokull Siple Wrangell
Chiginagak Hekla La Palma Osorno Sirung Yakedake
Chikurachki Helgrindur Lamington Pacaya Slamet Yasur
Chiles-Cerro Negro Hierro Lamongan Pagan Snaefellsjokull Yufu-Tsurumi
Chillan, Nevados de Hokkaido-Komagatake Langila Palena Volcanic Group Soputan Zaozan [Zaosan]
Chirinkotan Home Reef Lanin Paluweh Sorikmarapi Zavodovski
Chirpoi Hood Lascar Panarea Sotara Zhupanovsky
Ciremai Huaynaputina Late Papandayan Soufriere Hills Zubair Group
Cleveland Hudson, Cerro Lateiki Pavlof Soufriere St. Vincent
Colima Huila, Nevado del Lengai, Ol Doinyo Pelee South Sarigan Seamount
Colo Hunga Tonga-Hunga Ha'apai Leroboleng Peuet Sague Spurr
Concepcion Ibu Lewotobi Pinatubo St. Helens
Copahue Ijen Lewotolok Planchon-Peteroa Stromboli
Cotopaxi Iliamna Little Sitkin Poas Sulu Range
 News Feeds and Google Placemarks


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The RSS (Really Simple Syndication) feed is identical to the Weekly Volcanic Activity Report minus some features including the header information (latitude and longitude and summit elevation), the Geologic Summary, and a link to the volcano's page from the Global Volcanism Program. At the end of each report is a list of the sources used. Each volcano report includes a link from the volcano's name back to the more complete information in the Weekly Volcanic Activity Report on the Smithsonian website. This feature was first made available on 5 March 2008.



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A Google Earth network link for the Weekly Volcanic Activity Report can be loaded into the free Google Earth software, and in turn will load placemarks for volcanoes in the current weekly report. Placemark balloons include the volcano name, report date, report text, sources, and links back to the GVP volcano profile page and to the complete Weekly Report for that week. This feature was first made available on 1 April 2009.

 Criteria & Disclaimers

Criteria



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.

Disclaimers



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)

Report for Antuco
The Buenos Aires VAAC reported that only gas and steam rose from Antuco on 20 April; although a pilot reported ash emissions, ash was not identified in satellite imagery or by web camera during clear skies.
Source: Buenos Aires Volcanic Ash Advisory Center (VAAC)
Report for Tungurahua
IG reported that during 24-26 April activity at Tungurahua was low. On 27 April seismic activity increased; an ash plume rose 2 km above the crater and drifted NW, causing ashfall in Juive (7 km NNW). During the morning on 28 April steam-and-ash plumes rose 1-4 km and drifted at least 100 km SW and W. Later that day several explosions produced ash plumes that rose as high as 3.5 km and drifted W. Ashfall was reported in Baños (8 km N), Chacauco (NW), Bilbao (8 km W), Cusúa (8 km NW), Juive, Pondoa (8 km N), and Pillate (8 km W). At 1830 a steam-and-ash plume rose 5 km, and drifted SW and then W. Another explosion ejected incandescent blocks that fell on the flanks 400 m below the crater. During breaks in cloud cover on 29 April dark gray emissions were observed drifting ESE. Ashfall was reported in El Manzano (8 km SW), Cahuají (8 km SW), Puela (8 km SW), Penipe (15 km SW), and Riobamba (30 km S). An explosion caused structures to vibrate. On 30 April explosions produced ash plumes that rose 1.5-2 km and drifted WSW.
Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Report for Aira
JMA reported that during 22-25 April four explosions from Sakura-jima's Showa Crater ejected tephra at most 1.3 km from the crater. Crater incandescence was occasionally detected at night. Based on a pilot report, the Tokyo VAAC reported that ash plumes drifted NE and SE at altitudes of 2.7-3 km (9,000-10,000 ft) a.s.l. during 24-25 April. Explosions on 26 and during 28-29 April produced plumes that rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted SE and NE.
Sources: Tokyo Volcanic Ash Advisory Center (VAAC), Japan Meteorological Agency (JMA)
Report for Batu Tara
Based on analyses of satellite imagery and wind data, the Darwin Volcanic Ash Advisory Centre (VAAC) reported that during 24-30 April ash plumes from Batu Tara rose to altitudes of 1.5-2.1 km (5,000-7,000 ft) a.s.l. and drifted 35-110 km W, WNW, and NW.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Chirpoi
SVERT reported that a weak thermal anomaly over Snow, a volcano of Chirpoi, was detected in satellite images on 24 and 26 April.
Source: Sakhalin Volcanic Eruption Response Team (SVERT)
Report for Etna
Sezione di Catania - Osservatorio Etneo reported that the thirteenth lava-fountaining episode of 2013 began at Etna's New Southeast Crater (NSEC) on 27 April. Activity increased on 21 April and was characterized by Strombolian explosions and frequent ash emissions. Eruptive activity and the volcanic tremor amplitude gradually increased in the evening of 26 April. Just after sunset on 27 April lava fountains rose 300-500 m, and lava flows from the SE and NE flanks of the NSEC cone and from the saddle between the two Southeast Crater (SEC) cones traveled S and N.

Sezione di Catania - Osservatorio Etneo reported that the thirteenth lava-fountaining episode of 2013 began at Etna's New Southeast Crater (NSEC) on 27 April. Activity increased on 21 April and was characterized by Strombolian explosions and frequent ash emissions. Eruptive activity and the volcanic tremor amplitude gradually increased in the evening of 26 April. Just after sunset on 27 April lava fountains rose 300-500 m, and lava flows from the SE and NE flanks of the NSEC cone and from the saddle between the two Southeast Crater (SEC) cones traveled S and N.
Source: Sezione di Catania - Osservatorio Etneo (INGV)
Report for Fuego
INSIVUMEH reported that during 23-26 April explosions from Fuego generated ash plumes that rose 250-600 m above the crater and drifted at most 10 km W, SW, S, and SE. Incandescent material was ejected 100-200 m above the crater. In a special bulletin on 25 April INSIVUMEH noted that the energy of the explosions had increased, producing rumblings and shock waves that vibrated structures in Panimaché, Morelia, and Sangre de Cristo, as far as 10 km S and SW. A 300-m-long lava flow was active on the S flank in the Trinidad drainage. On 26 April a lava flow in the Taniluya drainage (SW) traveled as far as 400 m. On 28 April activity again increased and 700-m-long lava flows were active in the Taniluya and Ceniza drainages. Incandescent block avalanches reached vegetated areas. Cloud cover prevented observations of the crater. On 29 April explosions generated ash plumes that rose 550 m above the crater and drifted 10 km SSW. Lava flows remained active.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Gaua
The Wellington VAAC reported that on 29 April a plume from Gaua was observed from an aircraft. Satellite imagery did not indicate ash.
Source: Wellington Volcanic Ash Advisory Center (VAAC)
Report for Kilauea
During 24-30 April HVO reported that the circulating lava lake periodically rose and fell in the deep pit within Kilauea's Halema'uma'u Crater. The plume from the vent continued to deposit variable amounts of ash, spatter, and Pele's hair onto nearby areas.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Report for Kizimen
KVERT reported that during 19-26 April moderate seismic activity continued at Kizimen. Video and satellite data showed that lava continued to extrude from the summit, producing incandescence, strong gas-and-steam activity, and hot avalanches on the W and E flanks. Cloud-free satellite images detected a thermal anomaly over the volcano. The Aviation Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Manam
RVO reported that on 23 April dense white vapor plumes occasionally rose from Manam's Southern Crater. During 25-28 April ash clouds rose from the new sub-terminal vent E of Southern Crater inside southeast valley. The ash clouds rose 600 m and drifted NW. Loud booming noises were heard each day; however, between 0700 and 1900 on 27 April the noises became frequent, louder, and explosive in nature, and were heard at Bogia, 25-30 km SSW of Manam on the N coast of the mainland. Strong explosions vibrated structures on the island.
Source: Rabaul Volcano Observatory (RVO)
Report for Pacaya
INSIVUMEH reported that on 23 April fumarolic plumes from Pacaya's MacKenney cone rose 100 m and drifted N. On 24 April tephra was ejected 25 m high by weak explosions. Incandescence from the crater was observed through the night, and explosions were detected the next day. Incandescence and explosions were again detected on 29 April.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Paluweh
Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 29-30 April ash plumes from Paluweh rose to altitudes of 2.1-3 km (7,000-10,000 ft) a.s.l. and drifted 35-110 km NW and W.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Popocatepetl
CENAPRED reported that during 24-27 April seismicity at Popocatépetl indicated continuing gas-and-steam emissions that sometimes contained ash. Incandescence from the crater was often observed at night. Gas-and-steam plumes rose 1 km and drifted NE and ESE. On 24 April an explosion generated a steam-and-ash plume that rose 1.2 km above the crater and drifted W; incandescent tephra ejected from the crater landed 500 m away on the N flank. On 25 April a dense steam-and-gas plume rose 1.5 km and drifted W. The next day an explosion generated a gas-and-ash plume that rose 2 km. Atmospheric clouds made observations difficult. On 28 April gas-and-ash plumes rose 1.2 km and drifted NE, and on 29 April gas-and-ash plumes rose 1 km; cloud cover continued to impede observations. On 30 April an explosion generated an ash plume that rose 300 m and drifted E. Ejected incandescent tephra landed 800 m away on the NE flank. Gas-and-vapor plumes rose 500 m. The Alert Level remained at Yellow, Phase Two.
Source: Centro Nacional de Prevencion de Desastres (CENAPRED)
Report for Rabaul
RVO reported that during 24-28 April white vapor plumes sometimes containing ash rose at most 200 m from Rabaul caldera's Tavurvur cone and drifted SE. Roaring and rumbling noises also continued but the intensity was low.
Source: Rabaul Volcano Observatory (RVO)
Report for Sangay
Based on analyses of satellite imagery and a SIGMET aviation notice, the Washington VAAC reported that on 26 April two brief ash emissions from Sangay drifted SW and dissipated within 20 km. A thermal anomaly was visible in infrared satellite images.
Source: Washington Volcanic Ash Advisory Center (VAAC)
Report for Santa Maria
INSIVUMEH reported that on 23 April two explosions were accompanied by white plumes that rose 800 m above Santa María's Santiaguito lava-dome complex and drifted SW. The next day explosions produced ash plumes that rose 600 m and drifted SSW. Avalanches were generated by active lava flows on the SW flank. Explosions were heard on 25 April but cloud cover prevented visual confirmation. On 28 April a small explosion generated a white plume that rose 500 m and drifted NE. Explosions on 29 April produced ash plumes that rose 800 m and drifted SE, causing ashfall in San Jose, La Quina, and areas near Calahuache.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Sheveluch
Based on visual observations and analyses of satellite data, KVERT reported that during 19-26 April a viscous lava flow effused on the NW flank of Shiveluch's lava dome, accompanied by hot avalanches, incandescence, and fumarolic activity. Satellite imagery showed a daily thermal anomaly on the lava dome. The Aviation Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Soufriere Hills
MVO reported that during 19-26 April activity at the Soufrière Hills lava dome was at a low level. There had been no good views of the lava dome for over a month, but reports from helicopter pilots suggested that the most of the large slab that was on the E side of the lava dome was gone, likely removed during the pyroclastic flow on 28 March. The Hazard Level remained at 2 (on a scale of 1-5).
Source: Montserrat Volcano Observatory (MVO)
Report for Tolbachik
KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a lava plateau on the SW side of Tolbachik, continued to produce very fluid lava flows during 19-26 April that traveled to the W, S, and E sides of the plateau. Cinder cones continued to grow along the S fissure. Gas-and-ash plumes rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted in multiple directions. A large thermal anomaly on the N part of Tolbachinsky Dol was visible daily in satellite imagery. The Aviation Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Whakaari/White Island
On 29 April GeoNet Data Centre reported that activity at White Island remained at a persistently low level, characterized by tremor and degassing. No mud or ash eruptions had been observed since early April. A volcanologist visited the island the previous week and observed that increased rainfall had caused the two lakes to merge together into one larger lake. The temperature of the lake was 62 degrees Celsius and the lava-dome temperature was 200 degrees. The lower level of activity prompted GeoNet to reduce the Aviation Colour Code to Green (indicating no active eruption). The Volcano Alert Level remained at 1 (on a scale of 0-5).
Source: GeoNet