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Fine ash emissions and increased tremor at Planchón-Peteroa, Chile–Argentina

Oct 6 2025 at 10:14:31 UTC

The Argentine Geological and Mining Service (SEGEMAR) reported increased surface activity at the Planchón-Peteroa volcanic complex starting at 01:00 LT (04:00 UTC) on October 3, 2025, including emissions of fine volcanic ash rising up to 250 m (820 feet) above the crater. The technical alert remains at Yellow, with continued binational monitoring by SEGEMAR and Chile’s National Geology and Mining Service (SERNAGEOMIN).
Source
Kronotsky volcano awakens after a century, sending ash up to 9 km (30 000 feet) a.s.l., Russia

Oct 4 2025 at 12:42:00 UTC

Kronotsky volcano in Kamchatka, Russia, erupted at 03:50 UTC (15:50 LT) on October 4, 2025, ending a century of dormancy. The Kamchatka Volcanic Eruption Response Team (KVERT) reported an explosive eruption with an ash column reaching 9.2 km (30 180 feet) above sea level. Aviation Color Code was raised to Red. KVERT warns that additional ash emissions rising up to 15 km (49 200 feet) remain possible.
Source

Worldwide Volcano News

Volcanoes Today, 11 Oct 2025: Santiaguito volcano, Fuego, Popocatépetl, Semeru, Ibu, Dukono, Reventador, Sangay
Oct 11 2025 at 9:00 am EDT

Ibu Volcano Volcanic Ash Advisory: GROUND REPORT OF ERUPTION AT 11/1200Z OBS VA DTG: 11/1210Z to 10000 ft (3000 m)
Oct 11 2025 at 8:45 am EDT

Satellite image of Ibu volcano on 11 Oct 2025

Dukono Volcano Volcanic Ash Advisory: VA TO FL070 LAST AT 11/0000Z MOV S EST VA DTG: 11/1140Z to 7000 ft (2100 m)
Oct 11 2025 at 8:00 am EDT

Reventador Volcano Volcanic Ash Advisory: VA EMS PSBL
Oct 11 2025 at 7:00 am EDT

Sangay Volcano Volcanic Ash Advisory: VA EMS OBS to 21000 ft (6400 m)
Oct 11 2025 at 6:45 am EDT

Semeru Volcano Volcanic Ash Advisory: ERUPTION LAST REP AT 11/0750Z EST VA DTG: 11/0940Z
Oct 11 2025 at 6:15 am EDT

Popocatépetl Volcano Volcanic Ash Advisory: DISCRETE VA EM. to 21000 ft (6400 m)
Oct 11 2025 at 5:00 am EDT

Fuego Volcano Volcanic Ash Advisory: OCNL VA EMS.
Oct 11 2025 at 4:00 am EDT

Santiaguito Volcano Volcanic Ash Advisory: MULT VA EMS. to 14000 ft (4300 m)
Oct 11 2025 at 3:45 am EDT

Dukono Volcano Volcanic Ash Advisory: VA TO FL070 OBS 10/2340Z MOV SSE OBS VA DTG: 10/2340Z to 7000 ft (2100 m)
Oct 10 2025 at 8:15 pm EDT

Reventador Volcano Volcanic Ash Advisory: NEW VA EMS to 16000 ft (4900 m)
Oct 10 2025 at 8:00 pm EDT

Semeru Volcano Volcanic Ash Advisory: ERUPTION LAST REP AT 10/1745Z EST VA DTG: 10/2130Z
Oct 10 2025 at 6:15 pm EDT

Satellite image of Semeru volcano on 10 Oct 2025

Volcanic activity worldwide 10 Oct 2025: Santiaguito volcano, Fuego, Popocatépetl, Semeru, Ibu, Lew...
Oct 10 2025 at 5:00 pm EDT

Map of today's active volcanoes
Suwanose-jima (Ryukyu Islands): (10 Oct) Volcanic Ash Advisory Center Tokyo (VAAC) issued the following report: VA AT 20251010/0445Z REPORTED OBS VA DTG:10/0450Z

Ibu (Halmahera, Indonesia): (10 Oct) Explosive activity continues. Volcanic Ash Advisory Center (VAAC) Darwin warned about a volcanic ash plume that rose up to estimated 6000 ft (1800 m) altitude or flight level 060 and is moving at 05 kts in SE direction.
The full report is as follows: VA TO FL060 REP 10/0746Z EST VA DTG:10/0810Z to 6000 ft (1800 m)

Lewotobi (Flores): Explosive activity continues. Volcanic Ash Advisory Center (VAAC) Darwin warned about a volcanic ash plume that rose up to estimated 8000 ft (2400 m) altitude or flight level 080 .
The full report is as follows: VA TO FL080 REP AT 10/0727Z EST VA DTG:10/1800Z to 8000 ft (2400 m)

Lewotolo (Lesser Sunda Islands): Explosive activity continues. Volcanic Ash Advisory Center (VAAC) Darwin warned about a volcanic ash plume that rose up to estimated 7000 ft (2100 m) altitude or flight level 070 and is moving at 15 kts in W direction.
The full report is as follows: VA TO FL070 REP AT 10/0929Z EST VA DTG:10/0930Z to 7000 ft (2100 m)

Semeru (East Java, Indonesia): Volcanic Ash Advisory Center Darwin (VAAC) issued the following report: ERUPTION LAST REP AT 10/0940Z EST VA DTG:10/0940Z

Popocatépetl (Central Mexico): Explosive activity continues. Volcanic Ash Advisory Center (VAAC) Washington warned about a volcanic ash plume that rose up to estimated 19000 ft (5800 m) altitude or flight level 190 .
The full report is as follows: NEW VA EMS to 19000 ft (5800 m)

Santiaguito (Guatemala): Explosive activity continues. Volcanic Ash Advisory Center (VAAC) Washington warned about a volcanic ash plume that rose up to estimated 14000 ft (4300 m) altitude or flight level 140 .
The full report is as follows: NEW VA EMS to 14000 ft (4300 m)

Fuego (Guatemala): Explosive activity continues. Volcanic Ash Advisory Center (VAAC) Washington warned about a volcanic ash plume that rose up to estimated 14000 ft (4300 m) altitude or flight level 140 .
The full report is as follows: ONGOING VA EMS to 14000 ft (4300 m)

Planchón-Peteroa (Central Chile and Argentina): (9 Oct) Volcanic Ash Advisory Center Buenos Aires (VAAC) issued the following report: WV AND PSBL LIGHT VA

Tinguiririca (Central Chile and Argentina): Volcanic Ash Advisory Center Buenos Aires (VAAC) issued the following report: VA REPORTED 10/0955
Volcano Activity Summary for 10 Oct 2025:

Fuego Volcano Volcanic Ash Advisory: ONGOING VA EMS to 14000 ft (4300 m)
Oct 10 2025 at 4:00 pm EDT

Santiaguito Volcano Volcanic Ash Advisory: NEW VA EMS to 14000 ft (4300 m)
Oct 10 2025 at 3:00 pm EDT

Satellite image of Santiaguito volcano on 10 Oct 2025

Popocatépetl Volcano Volcanic Ash Advisory: NEW VA EMS to 19000 ft (5800 m)
Oct 10 2025 at 2:45 pm EDT

Lewotobi Volcano Volcanic Ash Advisory: VA TO FL080 REP AT 10/0727Z EST VA DTG: 10/1800Z to 8000 ft (2400 m)
Oct 10 2025 at 2:45 pm EDT

Volcanic activity worldwide 9 Oct 2025: Santiaguito volcano, Fuego, Karymsky, Klyuchevskoy, Merapi, ...
Oct 9 2025 at 5:00 pm EDT

Map of today's active volcanoes
Svartsengi (Reykjanes peninsula, SW Iceland): The Icelandic Meteorological Office (IMO) reported that by 23 September around 10 million cubic meters of magma had accumulated beneath Svartsengi since the last eruption within the Reykjanes volcanic system ended on 5 August. Data showed that magma was accumulating at around 4 km depth. The rate of magma accumulation was steady; model calculations based on deformation measurements indicated that by 27 September the volume may reach 11 million cubic meters, a volume that in some previous cases was followed by eruptions.
Since the likelihood of an eruption had increased, IMO raised the Volcanic Alert Level System (VAL) to 2 (on a scale of 0-3) on 25 September and concurrently a risk assessment map of the area was also updated.
... [read more]
...9 Oct:
The Icelandic Meteorological Office (IMO) reported that by 23 September around 10 million cubic meters of magma had accumulated beneath Svartsengi since the last eruption within the Reykjanes volcanic system ended on 5 August. Data showed that magma was accumulating at around 4 km depth. The rate of magma accumulation was steady; model calculations based on deformation measurements indicated that by 27 September the volume may reach 11 million cubic meters, a volume that in some previous cases was followed by eruptions.
Since the likelihood of an eruption had increased, IMO raised the Volcanic Alert Level System (VAL) to 2 (on a scale of 0-3) on 25 September and concurrently a risk assessment map of the area was also updated.
... [read more]
...8 Oct:
The Icelandic Meteorological Office (IMO) reported that by 23 September around 10 million cubic meters of magma had accumulated beneath Svartsengi since the last eruption within the Reykjanes volcanic system ended on 5 August. Data showed that magma was accumulating at around 4 km depth. The rate of magma accumulation was steady; model calculations based on deformation measurements indicated that by 27 September the volume may reach 11 million cubic meters, a volume that in some previous cases was followed by eruptions.
Since the likelihood of an eruption had increased, IMO raised the Volcanic Alert Level System (VAL) to 2 (on a scale of 0-3) on 25 September and concurrently a risk assessment map of the area was also updated.
... [read more]

Krasheninnikov (Kamchatka, Russia): The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that the eruption at Krasheninnikov continued during 18-25 September. A daily large thermal anomaly over the volcano was identified in satellite images. Explosions at Northern Cone produced ash plumes that rose 2.4 km a.s.l., or nearly 600 m above the summit, and drifted 260 km SE and E during 23-25 September.
A commercial satellite image on 25 September showed that lava flows had traveled 2.9 km NW, 2.8 km NE, and 3 km ENE. The upper half of the ENE flows were incandescent along with the main vent of Northern Cone. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).
... [read more]
...9 Oct:
The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that the eruption at Krasheninnikov continued during 18-25 September. A daily large thermal anomaly over the volcano was identified in satellite images. Explosions at Northern Cone produced ash plumes that rose 2.4 km a.s.l., or nearly 600 m above the summit, and drifted 260 km SE and E during 23-25 September.
A commercial satellite image on 25 September showed that lava flows had traveled 2.9 km NW, 2.8 km NE, and 3 km ENE. The upper half of the ENE flows were incandescent along with the main vent of Northern Cone. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).
... [read more]
...8 Oct:
The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that the eruption at Krasheninnikov continued during 18-25 September. A daily large thermal anomaly over the volcano was identified in satellite images. Explosions at Northern Cone produced ash plumes that rose 2.4 km a.s.l., or nearly 600 m above the summit, and drifted 260 km SE and E during 23-25 September.
A commercial satellite image on 25 September showed that lava flows had traveled 2.9 km NW, 2.8 km NE, and 3 km ENE. The upper half of the ENE flows were incandescent along with the main vent of Northern Cone. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).
... [read more]

Klyuchevskoy (Kamchatka): The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that wind was no longer resuspending ash previously deposited on the N flank of Klyuchevskoy. Only fumarolic emissions were observed. The Aviation Color Code was lowered to Green (the lowest level on a four-color scale) on 25 September.
Dates and times are provided in Coordinated Universal Time (UTC); specific events are indicated in local time where specified.
... [read more]
...9 Oct:
The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that wind was no longer resuspending ash previously deposited on the N flank of Klyuchevskoy. Only fumarolic emissions were observed. The Aviation Color Code was lowered to Green (the lowest level on a four-color scale) on 25 September.
Dates and times are provided in Coordinated Universal Time (UTC); specific events are indicated in local time where specified.
... [read more]
...8 Oct:
The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that wind was no longer resuspending ash previously deposited on the N flank of Klyuchevskoy. Only fumarolic emissions were observed. The Aviation Color Code was lowered to Green (the lowest level on a four-color scale) on 25 September.
Dates and times are provided in Coordinated Universal Time (UTC); specific events are indicated in local time where specified.
... [read more]

Karymsky (Kamchatka): The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that explosions at Karymsky were last observed in August. In September activity was at moderate levels characterized by steam-and-gas emissions and a weak thermal anomaly identified in satellite images; weather clouds sometimes obscured views. On 25 September the Aviation Color Code was lowered to Yellow (the second level on a four-color scale).
Dates and times are provided in Coordinated Universal Time (UTC); specific events are indicated in local time where specified.
... [read more]
...9 Oct:
The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that explosions at Karymsky were last observed in August. In September activity was at moderate levels characterized by steam-and-gas emissions and a weak thermal anomaly identified in satellite images; weather clouds sometimes obscured views. On 25 September the Aviation Color Code was lowered to Yellow (the second level on a four-color scale).
Dates and times are provided in Coordinated Universal Time (UTC); specific events are indicated in local time where specified.
... [read more]
...8 Oct:
The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that explosions at Karymsky were last observed in August. In September activity was at moderate levels characterized by steam-and-gas emissions and a weak thermal anomaly identified in satellite images; weather clouds sometimes obscured views. On 25 September the Aviation Color Code was lowered to Yellow (the second level on a four-color scale).
Dates and times are provided in Coordinated Universal Time (UTC); specific events are indicated in local time where specified.
... [read more]

Shiveluch (Kamchatka): The Kamchatkan Volcanic Eruption Response Team (KVERT) reported continuing eruptive activity at Sheveluch’s “300 years of RAS” dome on the SW flank of Old Sheveluch and at the Young Sheveluch dome during 18-25 September. Daily thermal anomalies over the domes were identified in satellite images. Ash plumes were identified in satellite and webcam images rising to 5 km a.s.l. and drifting more than 150 km SE and NW during 18-19 September.
Plumes of resuspended ash drifted 1,700 km E and SE during 23-25 September. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Dates are based on UTC; specific events are in local time where noted.
... [read more]
...9 Oct:
The Kamchatkan Volcanic Eruption Response Team (KVERT) reported continuing eruptive activity at Sheveluch’s “300 years of RAS” dome on the SW flank of Old Sheveluch and at the Young Sheveluch dome during 18-25 September. Daily thermal anomalies over the domes were identified in satellite images. Ash plumes were identified in satellite and webcam images rising to 5 km a.s.l. and drifting more than 150 km SE and NW during 18-19 September.
Plumes of resuspended ash drifted 1,700 km E and SE during 23-25 September. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Dates are based on UTC; specific events are in local time where noted.
... [read more]
...8 Oct:
The Kamchatkan Volcanic Eruption Response Team (KVERT) reported continuing eruptive activity at Sheveluch’s “300 years of RAS” dome on the SW flank of Old Sheveluch and at the Young Sheveluch dome during 18-25 September. Daily thermal anomalies over the domes were identified in satellite images. Ash plumes were identified in satellite and webcam images rising to 5 km a.s.l. and drifting more than 150 km SE and NW during 18-19 September.
Plumes of resuspended ash drifted 1,700 km E and SE during 23-25 September. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Dates are based on UTC; specific events are in local time where noted.
... [read more]

Sakurajima (Kyushu, Japan): The Japan Meteorological Agency (JMA) reported ongoing eruptive activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 22-29 September. Nightly crater incandescence was visible in webcam images. A very small eruptive event was recorded on 27 September.
The Alert Level remained at 3 (on a 5-level scale), and the public was warned to be cautious within 2 km of both the Minimadake and Showa craters.
... [read more]
...9 Oct:
The Japan Meteorological Agency (JMA) reported ongoing eruptive activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 22-29 September. Nightly crater incandescence was visible in webcam images. A very small eruptive event was recorded on 27 September.
The Alert Level remained at 3 (on a 5-level scale), and the public was warned to be cautious within 2 km of both the Minimadake and Showa craters.
... [read more]
...8 Oct:
The Japan Meteorological Agency (JMA) reported ongoing eruptive activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 22-29 September. Nightly crater incandescence was visible in webcam images. A very small eruptive event was recorded on 27 September.
The Alert Level remained at 3 (on a 5-level scale), and the public was warned to be cautious within 2 km of both the Minimadake and Showa craters.
... [read more]

Suwanose-jima (Ryukyu Islands): (9 Oct) Volcanic Ash Advisory Center Tokyo (VAAC) issued the following report: ACTIVITY CONT. VA AT 20251009/0600Z FL060 EXTD W OBS VA DTG:09/0600Z
...9 Oct:
The Japan Meteorological Agency (JMA) reported that eruptive activity at Suwanosejima's Ontake Crater continued during 22-29 September. Incandescence was observed nightly in webcam images. Eruptive events during 23-28 September generated ash plumes that rose 1-1.6 km above the crater rim and drifted mainly N, NW, and E.
Small amounts of ashfall were reported in Toshima Village (3.5 km SSW) on 27 September. Ash emissions were continuous from 2238 on 27 September to 0100 on 28 September. The Alert Level remained at 2 (the second level on a five-level scale) and the public was warned to be cautious within 1.5 km of the crater.
... [read more]
...9 Oct:
The Japan Meteorological Agency (JMA) reported that eruptive activity at Suwanosejima's Ontake Crater continued during 22-29 September. Incandescence was observed nightly in webcam images. Eruptive events during 23-28 September generated ash plumes that rose 1-1.6 km above the crater rim and drifted mainly N, NW, and E.
Small amounts of ashfall were reported in Toshima Village (3.5 km SSW) on 27 September. Ash emissions were continuous from 2238 on 27 September to 0100 on 28 September. The Alert Level remained at 2 (the second level on a five-level scale) and the public was warned to be cautious within 1.5 km of the crater.
... [read more]
...8 Oct:
The Japan Meteorological Agency (JMA) reported that eruptive activity at Suwanosejima's Ontake Crater continued during 22-29 September. Incandescence was observed nightly in webcam images. Eruptive events during 23-28 September generated ash plumes that rose 1-1.6 km above the crater rim and drifted mainly N, NW, and E.
Small amounts of ashfall were reported in Toshima Village (3.5 km SSW) on 27 September. Ash emissions were continuous from 2238 on 27 September to 0100 on 28 September. The Alert Level remained at 2 (the second level on a five-level scale) and the public was warned to be cautious within 1.5 km of the crater.
... [read more]

Ibu (Halmahera, Indonesia): Volcanic Ash Advisory Center Darwin (VAAC) issued the following report: VA LAST GND RPT TO FL060 AT 09/1026Z EST VA DTG:09/1330Z
...9 Oct:
The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that the eruption at Ibu continued during 24-30 September. Dense gray or white-and-gray ash plumes rose 300-700 m above the summit and drifted in multiple directions. Incandescence at the summit was visible in a few nighttime webcam images.
The Alert Level remained at 2 (the second lowest level on a four-level scale) and the public was advised to stay 2 km away from the active crater and 3.5 km away from the N crater wall opening.
... [read more]
...9 Oct:
The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that the eruption at Ibu continued during 24-30 September. Dense gray or white-and-gray ash plumes rose 300-700 m above the summit and drifted in multiple directions. Incandescence at the summit was visible in a few nighttime webcam images.
The Alert Level remained at 2 (the second lowest level on a four-level scale) and the public was advised to stay 2 km away from the active crater and 3.5 km away from the N crater wall opening.
... [read more]
...8 Oct:
The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that the eruption at Ibu continued during 24-30 September. Dense gray or white-and-gray ash plumes rose 300-700 m above the summit and drifted in multiple directions. Incandescence at the summit was visible in a few nighttime webcam images.
The Alert Level remained at 2 (the second lowest level on a four-level scale) and the public was advised to stay 2 km away from the active crater and 3.5 km away from the N crater wall opening.
... [read more]

Lewotobi (Flores): (9 Oct) Explosive activity continues. Volcanic Ash Advisory Center (VAAC) Darwin warned about a volcanic ash plume that rose up to estimated 12000 ft (3700 m) altitude or flight level 120 .
The full report is as follows: VA TO FL120 OBS AT 09/0620 MOV SW OBS VA DTG:09/0620Z to 12000 ft (3700 m)
...9 Oct:
The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that daily white-and-gray or gray ash plumes with variable densities rose as high as 2 km above the summit of Lewotobi Laki-laki and drifted N, NW, W, and SW during 23-29 September. According to a news article the Fransiskus Xaverius Seda Airport (60 km W) was closed on 26 September through early 27 September; volcanic ash caused six flights to be canceled. PVMBG noted that seismic activity during the week was dominated by low-frequency earthquakes, non-harmonic tremor, and signals indicating eruptive events and emissions.
The number of explosions fluctuated at moderate levels and the number of deep volcanic earthquakes declined. Tilt data indicated inflation at shallow depths and GNSS (Global Navigation Satellite System) data showed continuing deformation. At 1500 on 29 September the Alert Level was lowered to 3 (on a scale of 1-4) and the public was warned to stay 6 km away from the center of Laki-laki.
... [read more]
...9 Oct:
The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that daily white-and-gray or gray ash plumes with variable densities rose as high as 2 km above the summit of Lewotobi Laki-laki and drifted N, NW, W, and SW during 23-29 September. According to a news article the Fransiskus Xaverius Seda Airport (60 km W) was closed on 26 September through early 27 September; volcanic ash caused six flights to be canceled. PVMBG noted that seismic activity during the week was dominated by low-frequency earthquakes, non-harmonic tremor, and signals indicating eruptive events and emissions.
The number of explosions fluctuated at moderate levels and the number of deep volcanic earthquakes declined. Tilt data indicated inflation at shallow depths and GNSS (Global Navigation Satellite System) data showed continuing deformation. At 1500 on 29 September the Alert Level was lowered to 3 (on a scale of 1-4) and the public was warned to stay 6 km away from the center of Laki-laki.
... [read more]
...8 Oct:
The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that daily white-and-gray or gray ash plumes with variable densities rose as high as 2 km above the summit of Lewotobi Laki-laki and drifted N, NW, W, and SW during 23-29 September. According to a news article the Fransiskus Xaverius Seda Airport (60 km W) was closed on 26 September through early 27 September; volcanic ash caused six flights to be canceled. PVMBG noted that seismic activity during the week was dominated by low-frequency earthquakes, non-harmonic tremor, and signals indicating eruptive events and emissions.
The number of explosions fluctuated at moderate levels and the number of deep volcanic earthquakes declined. Tilt data indicated inflation at shallow depths and GNSS (Global Navigation Satellite System) data showed continuing deformation. At 1500 on 29 September the Alert Level was lowered to 3 (on a scale of 1-4) and the public was warned to stay 6 km away from the center of Laki-laki.
... [read more]

Lewotolo (Lesser Sunda Islands): The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that an eruption at Lewotolok was ongoing during 24-30 September. On most days white-and-gray ash plumes rose 100-600 m above the summit of the cone and drifted W and NW; only white plumes rising to 100 m above the summit were observed on 27 September. Several nighttime webcam images showed Strombolian ejections of incandescent material above the cone and onto the flanks.
The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit.
... [read more]
...9 Oct:
The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that an eruption at Lewotolok was ongoing during 24-30 September. On most days white-and-gray ash plumes rose 100-600 m above the summit of the cone and drifted W and NW; only white plumes rising to 100 m above the summit were observed on 27 September. Several nighttime webcam images showed Strombolian ejections of incandescent material above the cone and onto the flanks.
The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit.
... [read more]
...8 Oct:
The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that an eruption at Lewotolok was ongoing during 24-30 September. On most days white-and-gray ash plumes rose 100-600 m above the summit of the cone and drifted W and NW; only white plumes rising to 100 m above the summit were observed on 27 September. Several nighttime webcam images showed Strombolian ejections of incandescent material above the cone and onto the flanks.
The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit.
... [read more]

Merapi (Central Java, Indonesia): The Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG) reported that the eruption at Merapi (on Java) continued during 19-25 September. The SW lava dome produced 5 lava avalanches that traveled as far as 2 km SW down the Bebeng drainage, 37 that traveled as far as 2 km SW down the Krasak drainage, and 46 that traveled as far as 2 km W down the Sat/Putih drainage. Small morphological changes to the SW lava dome resulted from lava effusion and minor collapses.
The Alert Level remained at 3 (on a scale of 1-4), and the public was warned to stay 3-7 km away from the summit, based on location.
... [read more]
...9 Oct:
The Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG) reported that the eruption at Merapi (on Java) continued during 19-25 September. The SW lava dome produced 5 lava avalanches that traveled as far as 2 km SW down the Bebeng drainage, 37 that traveled as far as 2 km SW down the Krasak drainage, and 46 that traveled as far as 2 km W down the Sat/Putih drainage. Small morphological changes to the SW lava dome resulted from lava effusion and minor collapses.
The Alert Level remained at 3 (on a scale of 1-4), and the public was warned to stay 3-7 km away from the summit, based on location.
... [read more]
...8 Oct:
The Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG) reported that the eruption at Merapi (on Java) continued during 19-25 September. The SW lava dome produced 5 lava avalanches that traveled as far as 2 km SW down the Bebeng drainage, 37 that traveled as far as 2 km SW down the Krasak drainage, and 46 that traveled as far as 2 km W down the Sat/Putih drainage. Small morphological changes to the SW lava dome resulted from lava effusion and minor collapses.
The Alert Level remained at 3 (on a scale of 1-4), and the public was warned to stay 3-7 km away from the summit, based on location.
... [read more]

Semeru (East Java, Indonesia): Volcanic Ash Advisory Center Darwin (VAAC) issued the following report: VA LAST GND RPT TO FL140 AT 09/0228Z EST VA DTG:09/1540Z
...9 Oct:
The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that activity continued at Semeru during 24-30 September, with daily eruptive events recorded by the seismic network. Daily white-and-gray or gray ash plumes rose 400-900 m above the summit and drifted in multiple directions. The Alert Level remained at 2 (the second lowest level on a scale of 1-4).
The public was warned to stay at least 3 km away from the summit in all directions, 8 km from the summit to the SE, 500 m from the banks of the Kobokan drainage as far as 13 km from the summit, and to avoid other drainages including the Bang, Kembar, and Sat, due to lahar, avalanche, and pyroclastic flow hazards.
... [read more]
...9 Oct:
The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that activity continued at Semeru during 24-30 September, with daily eruptive events recorded by the seismic network. Daily white-and-gray or gray ash plumes rose 400-900 m above the summit and drifted in multiple directions. The Alert Level remained at 2 (the second lowest level on a scale of 1-4).
The public was warned to stay at least 3 km away from the summit in all directions, 8 km from the summit to the SE, 500 m from the banks of the Kobokan drainage as far as 13 km from the summit, and to avoid other drainages including the Bang, Kembar, and Sat, due to lahar, avalanche, and pyroclastic flow hazards.
... [read more]
...8 Oct:
The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that activity continued at Semeru during 24-30 September, with daily eruptive events recorded by the seismic network. Daily white-and-gray or gray ash plumes rose 400-900 m above the summit and drifted in multiple directions. The Alert Level remained at 2 (the second lowest level on a scale of 1-4).
The public was warned to stay at least 3 km away from the summit in all directions, 8 km from the summit to the SE, 500 m from the banks of the Kobokan drainage as far as 13 km from the summit, and to avoid other drainages including the Bang, Kembar, and Sat, due to lahar, avalanche, and pyroclastic flow hazards.
... [read more]

Marapi (Western Sumatra, Indonesia): Volcanic Ash Advisory Center Darwin (VAAC) issued the following report: VA GND RPT TO FL140 AT 09/1554Z EST VA DTG:09/1600Z
...9 Oct:
The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity at Marapi (on Sumatra) continued during 24-30 September. Eruptive events at 1959 on 24 September and at 2116 on 26 September were recorded but weather conditions prevented visual confirmation. An eruptive event at 1831 on 26 September produced a dense white-and-gray ash plume that rose 1 km above the summit and drifted E.
The Alert Level remained at 2 (on a scale of 1-4) and the public was warned to stay 3 km away from the active crater.
... [read more]
...9 Oct:
The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity at Marapi (on Sumatra) continued during 24-30 September. Eruptive events at 1959 on 24 September and at 2116 on 26 September were recorded but weather conditions prevented visual confirmation. An eruptive event at 1831 on 26 September produced a dense white-and-gray ash plume that rose 1 km above the summit and drifted E.
The Alert Level remained at 2 (on a scale of 1-4) and the public was warned to stay 3 km away from the active crater.
... [read more]
...8 Oct:
The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity at Marapi (on Sumatra) continued during 24-30 September. Eruptive events at 1959 on 24 September and at 2116 on 26 September were recorded but weather conditions prevented visual confirmation. An eruptive event at 1831 on 26 September produced a dense white-and-gray ash plume that rose 1 km above the summit and drifted E.
The Alert Level remained at 2 (on a scale of 1-4) and the public was warned to stay 3 km away from the active crater.
... [read more]

Dukono (Halmahera): The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity at Dukono continued during 24-30 September. White-and-gray gas-and-ash plumes rose as high as 700 m above the summit on most days and drifted E, NW, and W. White plumes rose as high as 200 m above the summit and drifted E and SW on 26 and 29 September.
The Alert Level remained at Level 2 (on a scale of 1-4) and the public was warned to stay 4 km away from the Malupang Warirang Crater.
... [read more]
...9 Oct:
The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity at Dukono continued during 24-30 September. White-and-gray gas-and-ash plumes rose as high as 700 m above the summit on most days and drifted E, NW, and W. White plumes rose as high as 200 m above the summit and drifted E and SW on 26 and 29 September.
The Alert Level remained at Level 2 (on a scale of 1-4) and the public was warned to stay 4 km away from the Malupang Warirang Crater.
... [read more]
...8 Oct:
The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity at Dukono continued during 24-30 September. White-and-gray gas-and-ash plumes rose as high as 700 m above the summit on most days and drifted E, NW, and W. White plumes rose as high as 200 m above the summit and drifted E and SW on 26 and 29 September.
The Alert Level remained at Level 2 (on a scale of 1-4) and the public was warned to stay 4 km away from the Malupang Warirang Crater.
... [read more]

Ambrym (Vanuatu): The Vanuatu Meteorology and Geohazards Department (VMGD) reported ongoing unrest at Ambrym during September. A weak thermal anomaly was detected in satellite images on 4 and 12 September. Seismic data confirmed ongoing unrest.
The Alert Level remained at 2 (on a scale of 0-5). VMGD warned the public to stay outside of Permanent Danger Zone A, defined as a 1-km radius around Benbow Crater and a 2-km radius around Marum Crater, and to stay 500 m away from the ground cracks created by the December 2018 eruption.
... [read more]
...9 Oct:
The Vanuatu Meteorology and Geohazards Department (VMGD) reported ongoing unrest at Ambrym during September. A weak thermal anomaly was detected in satellite images on 4 and 12 September. Seismic data confirmed ongoing unrest.
The Alert Level remained at 2 (on a scale of 0-5). VMGD warned the public to stay outside of Permanent Danger Zone A, defined as a 1-km radius around Benbow Crater and a 2-km radius around Marum Crater, and to stay 500 m away from the ground cracks created by the December 2018 eruption.
... [read more]
...8 Oct:
The Vanuatu Meteorology and Geohazards Department (VMGD) reported ongoing unrest at Ambrym during September. A weak thermal anomaly was detected in satellite images on 4 and 12 September. Seismic data confirmed ongoing unrest.
The Alert Level remained at 2 (on a scale of 0-5). VMGD warned the public to stay outside of Permanent Danger Zone A, defined as a 1-km radius around Benbow Crater and a 2-km radius around Marum Crater, and to stay 500 m away from the ground cracks created by the December 2018 eruption.
... [read more]

Lopevi (Vanuatu): The Vanuatu Meteorology and Geohazards Department (VMGD) reported that seismic data confirmed continuing unrest at Lopevi during September. Low-level thermal anomalies were identified in satellite images during 12-13 and 17 September. Small fumarolic steam plumes were continuously emitted from the summit crater on 22 September based on webcam images.
The Alert Level remained at 2 (on a scale of 0-4).
... [read more]
...9 Oct:
The Vanuatu Meteorology and Geohazards Department (VMGD) reported that seismic data confirmed continuing unrest at Lopevi during September. Low-level thermal anomalies were identified in satellite images during 12-13 and 17 September. Small fumarolic steam plumes were continuously emitted from the summit crater on 22 September based on webcam images.
The Alert Level remained at 2 (on a scale of 0-4).
... [read more]
...8 Oct:
The Vanuatu Meteorology and Geohazards Department (VMGD) reported that seismic data confirmed continuing unrest at Lopevi during September. Low-level thermal anomalies were identified in satellite images during 12-13 and 17 September. Small fumarolic steam plumes were continuously emitted from the summit crater on 22 September based on webcam images.
The Alert Level remained at 2 (on a scale of 0-4).
... [read more]

Yasur (Tanna Island, Vanuatu): The Vanuatu Meteorology and Geohazards Department (VMGD) reported that activity at Yasur continued at a level of “major unrest,” as defined by the Alert Level 2 status (on a scale of 0-5) during September. Sulfur dioxide gas emissions were identified in satellite images during 2-17 and 19-21 September, and low-level thermal anomalies were identified during 6-7, 9-12, 16-17, and 19 September. Field photos and webcam images indicated that explosions continued periodically, producing emissions of gas, steam, and/or ash during 3, 9-10, 12, 14, 16-19, 21, and 23-25 September.
Seismic data confirmed continuing volcanic activity with explosions that were occasionally strong. The report warned that ejected material from explosions could fall in and around the crater. The public was reminded to not enter the restricted area within 600 m around the boundaries of the Permanent Exclusion Zone, defined by Danger Zone A on the hazard map.
... [read more]
...9 Oct:
The Vanuatu Meteorology and Geohazards Department (VMGD) reported that activity at Yasur continued at a level of “major unrest,” as defined by the Alert Level 2 status (on a scale of 0-5) during September. Sulfur dioxide gas emissions were identified in satellite images during 2-17 and 19-21 September, and low-level thermal anomalies were identified during 6-7, 9-12, 16-17, and 19 September. Field photos and webcam images indicated that explosions continued periodically, producing emissions of gas, steam, and/or ash during 3, 9-10, 12, 14, 16-19, 21, and 23-25 September.
Seismic data confirmed continuing volcanic activity with explosions that were occasionally strong. The report warned that ejected material from explosions could fall in and around the crater. The public was reminded to not enter the restricted area within 600 m around the boundaries of the Permanent Exclusion Zone, defined by Danger Zone A on the hazard map.
... [read more]
...8 Oct:
The Vanuatu Meteorology and Geohazards Department (VMGD) reported that activity at Yasur continued at a level of “major unrest,” as defined by the Alert Level 2 status (on a scale of 0-5) during September. Sulfur dioxide gas emissions were identified in satellite images during 2-17 and 19-21 September, and low-level thermal anomalies were identified during 6-7, 9-12, 16-17, and 19 September. Field photos and webcam images indicated that explosions continued periodically, producing emissions of gas, steam, and/or ash during 3, 9-10, 12, 14, 16-19, 21, and 23-25 September.
Seismic data confirmed continuing volcanic activity with explosions that were occasionally strong. The report warned that ejected material from explosions could fall in and

Ibu volcano (Indonesia) - Smithsonian / USGS Weekly Volcanic Activity Report for 24 September-30 September 2025 (Continuing Activity)
Oct 9 2025 at 6:00 am EDT

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that the eruption at Ibu continued during 24-30 September. Dense gray or white-and-gray ash plumes rose 300-700 m above the summit and drifted in multiple directions. Incandescence at the summit was visible in a few nighttime webcam images.
The Alert Level remained at 2 (the second lowest level on a four-level scale) and the public was advised to stay 2 km away from the active crater and 3.5 km away from the N crater wall opening.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
---
From: Global Volcanism Program, 2025. Report on Ibu (Indonesia). In: Mayberry, G (ed.), Weekly Volcanic Activity Report 1 October-7 October 2025. Smithsonian Institution and US Geological Survey.

Great Sitkin volcano (United States) - Smithsonian / USGS Weekly Volcanic Activity Report for 24 September-30 September 2025 (Continuing Activity)
Oct 9 2025 at 6:00 am EDT

The Alaska Volcano Observatory (AVO) reported that slow lava effusion continued to feed a thick flow in Great Sitkin’s summit crater during 24-29 September. Satellite data indicated that the SE part of the flow slightly inflated. Advancement was detected around the SW, S, and SE margins of the flow; the fastest moving part of the flow advanced at a rate of about 5 m per day.
Small daily earthquakes were detected by the seismic network daily along with rockfall signals. Weather clouds often obscured satellite and webcam views, though elevated surface temperatures were identified in 29 September satellite views. The Volcano Alert Level remained at Watch (the third level on a four-level scale) and the Aviation Color Code remained at Orange (the third color on a four-color scale).

Source: US Geological Survey Alaska Volcano Observatory (AVO)
---
From: Global Volcanism Program, 2025. Report on Great Sitkin (United States). In: Mayberry, G (ed.), Weekly Volcanic Activity Report 1 October-7 October 2025. Smithsonian Institution and US Geological Survey.

Katmai volcano (United States) - Smithsonian / USGS Weekly Volcanic Activity Report for 24 September-30 September 2025 (Continuing Activity)
Oct 9 2025 at 6:00 am EDT

The Alaska Volcano Observatory (AVO) reported that on 27 September strong winds in the vicinity of Katmai and the Valley of Ten Thousand Smokes dispersed unconsolidated ash up to 1.8 km (6,000 ft) a.s.l. to the SE. The ash was originally deposited during the Novarupta-Katmai eruption in 1912.
The Volcano Alert Level remained at Normal (the lowest level on a four-level scale) and the Aviation Color Code remained at Green (the lowest level on a four-color scale).

Source: US Geological Survey Alaska Volcano Observatory (AVO)
---
From: Global Volcanism Program, 2025. Report on Katmai (United States). In: Mayberry, G (ed.), Weekly Volcanic Activity Report 1 October-7 October 2025. Smithsonian Institution and US Geological Survey.

Gaua volcano (Vanuatu) - Smithsonian / USGS Weekly Volcanic Activity Report for 24 September-30 September 2025 (Continuing Activity)
Oct 9 2025 at 6:00 am EDT

The Vanuatu Meteorology and Geohazards (VMGD) reported that unrest continued at Gaua during September. Sulfur dioxide emissions were identified in satellite images during 7, 9-10, and 20 September and steam and/or gas emissions were visible in satellite images rising from the vent during 7, 9, 11, and 17-18 September. A very low thermal anomaly was detected on 14 September.
The Alert Level remained at 2 (on a scale of 0-5) and the public was warned to stay away from the main cone.

Source: Vanuatu Meteorology and Geohazards Department (VMGD)
---
From: Global Volcanism Program, 2025. Report on Gaua (Vanuatu). In: Mayberry, G (ed.), Weekly Volcanic Activity Report 1 October-7 October 2025. Smithsonian Institution and US Geological Survey.

Karymsky volcano (Russia) - Smithsonian / USGS Weekly Volcanic Activity Report for 24 September-30 September 2025 (Continuing Activity)
Oct 9 2025 at 6:00 am EDT

The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that explosions at Karymsky were last observed in August. In September activity was at moderate levels characterized by steam-and-gas emissions and a weak thermal anomaly identified in satellite images; weather clouds sometimes obscured views. On 25 September the Aviation Color Code was lowered to Yellow (the second level on a four-color scale).
Dates and times are provided in Coordinated Universal Time (UTC); specific events are indicated in local time where specified.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
---
From: Global Volcanism Program, 2025. Report on Karymsky (Russia). In: Mayberry, G (ed.), Weekly Volcanic Activity Report 1 October-7 October 2025. Smithsonian Institution and US Geological Survey.

Ambrym volcano (Vanuatu) - Smithsonian / USGS Weekly Volcanic Activity Report for 24 September-30 September 2025 (Continuing Activity)
Oct 9 2025 at 6:00 am EDT

The Vanuatu Meteorology and Geohazards Department (VMGD) reported ongoing unrest at Ambrym during September. A weak thermal anomaly was detected in satellite images on 4 and 12 September. Seismic data confirmed ongoing unrest.
The Alert Level remained at 2 (on a scale of 0-5). VMGD warned the public to stay outside of Permanent Danger Zone A, defined as a 1-km radius around Benbow Crater and a 2-km radius around Marum Crater, and to stay 500 m away from the ground cracks created by the December 2018 eruption.

Source: Vanuatu Meteorology and Geohazards Department (VMGD)
---
From: Global Volcanism Program, 2025. Report on Ambrym (Vanuatu). In: Mayberry, G (ed.), Weekly Volcanic Activity Report 1 October-7 October 2025. Smithsonian Institution and US Geological Survey.

Aira volcano (Japan) - Smithsonian / USGS Weekly Volcanic Activity Report for 24 September-30 September 2025 (Continuing Activity)
Oct 9 2025 at 6:00 am EDT

The Japan Meteorological Agency (JMA) reported ongoing eruptive activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 22-29 September. Nightly crater incandescence was visible in webcam images. A very small eruptive event was recorded on 27 September.
The Alert Level remained at 3 (on a 5-level scale), and the public was warned to be cautious within 2 km of both the Minimadake and Showa craters.

Source: Japan Meteorological Agency (JMA)
---
From: Global Volcanism Program, 2025. Report on Aira (Japan). In: Mayberry, G (ed.), Weekly Volcanic Activity Report 1 October-7 October 2025. Smithsonian Institution and US Geological Survey.

Kilauea volcano (United States) - Smithsonian / USGS Weekly Volcanic Activity Report for 24 September-30 September 2025 (Continuing Activity)
Oct 9 2025 at 6:00 am EDT

The Hawaiian Volcano Observatory (HVO) reported that the eruption within Kilauea’s Kaluapele summit caldera, characterized by episodic fountaining, incandescence, and intermittent spatter from craters along the SW margin of Halema’uma’u Crater, continued at variable levels during 23-29 September. Incandescence at both the N and S vents was visible overnight during the week and gas plumes continued to be emitted from them. Scientists did not see lava in the vents during an overflight on 24 September.
Weak spattering and occasional flames at the N vent were visible during 27-28 September. Persistent glow from N vent overnight during 28-29 September was punctuated by nine gas-piston cycles of lava overflowing the cone and draining back into the cone. They were recorded at 2147 on 28 September and at 0215, at 0426, at 0512, at 0618, at 0632, at 0700, at 0740, and at 0814 on 29 September, and each lasted 5-10 minutes.
There was intermittent but strong incandescence at the S vent. The Volcano Alert Level remained at Watch (the third level on a four-level scale) and the Aviation Color Code remained at Orange (the third color on a four-color scale).

Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
---
From: Global Volcanism Program, 2025. Report on Kilauea (United States). In: Mayberry, G (ed.), Weekly Volcanic Activity Report 1 October-7 October 2025. Smithsonian Institution and US Geological Survey.

Ambae volcano (Vanuatu) - Smithsonian / USGS Weekly Volcanic Activity Report for 24 September-30 September 2025 (Continuing Activity)
Oct 9 2025 at 6:00 am EDT

The Vanuatu Meteorology and Geohazards Department (VMGD) reported ongoing unrest at Ambae during the month of September based on seismic and satellite data, webcam images, and field observations. Sulfur dioxide emissions were identified in satellite images during 1-10, 12-14, and 16-21 September. A very low-level thermal anomaly was also detected in satellite images during 11 and 20-22 September.
Steam and/or gas emissions were visible in satellite and webcam observations on 12 September. The Alert Level remained at 2 (on a scale of 0-5), and the public was warned to stay outside of Danger Zone A, defined as a 2-km radius around the active vents in Lake Voui, and to stay away from drainages during heavy rains.

Source: Vanuatu Meteorology and Geohazards Department (VMGD)
---
From: Global Volcanism Program, 2025. Report on Ambae (Vanuatu). In: Mayberry, G (ed.), Weekly Volcanic Activity Report 1 October-7 October 2025. Smithsonian Institution and US Geological Survey.

Dukono volcano (Indonesia) - Smithsonian / USGS Weekly Volcanic Activity Report for 24 September-30 September 2025 (Continuing Activity)
Oct 9 2025 at 6:00 am EDT

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity at Dukono continued during 24-30 September. White-and-gray gas-and-ash plumes rose as high as 700 m above the summit on most days and drifted E, NW, and W. White plumes rose as high as 200 m above the summit and drifted E and SW on 26 and 29 September.
The Alert Level remained at Level 2 (on a scale of 1-4) and the public was warned to stay 4 km away from the Malupang Warirang Crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
---
From: Global Volcanism Program, 2025. Report on Dukono (Indonesia). In: Mayberry, G (ed.), Weekly Volcanic Activity Report 1 October-7 October 2025. Smithsonian Institution and US Geological Survey.

Fuego volcano (Guatemala) - Smithsonian / USGS Weekly Volcanic Activity Report for 24 September-30 September 2025 (Continuing Activity)
Oct 9 2025 at 6:00 am EDT

The Instituto Nacional de Sismología, Vulcanologia, Meteorologia e Hidrología (INSIVUMEH) reported that eruptive activity at Fuego continued during 23-30 September. Daily Strombolian explosions were recorded by the seismic network at rates of 5-10 per hour. The explosions generated daily gas-and-ash plumes that rose as high as 1.1 km above the summit and drifted as far as 40 km NW, W, and SW.
Occasional rumbling sounds, shock waves, and/or sound associated with gas emissions were reported; the shock waves rattled buildings and structures in communities on the SW and W flanks during 23-24 September. Explosions ejected incandescent material 100-200 m above the summit during 27-30 September, sometimes showering the upper flanks with incandescent material. Daily block avalanches descended the flanks, including the Las Lajas (SE), Seca (W), Taniluya (SSW), Trinidad (SSW), Santa Teresa (W), and Ceniza (SSW) drainages, occasionally reaching vegetated areas.
Ashfall was reported in areas downwind including Finca Palo Verde (10 km WSW), Yepocapa (12 km SW), Sangre de Cristo (8 km W), El Porvenir (11 km SW), Quisaché (8 km NW), and Soledad (11 km N) during 23-24 September, in Yepocapa during 24-25 September, in areas on the SW flank during 25-26 September, and in Panimache (8 km SW), Sangre de Cristo, Finca Palo Verde, and Yepocapa during 28-29 September.

Heavy rain generated lahars in multiple drainages during 22-23, 25, and 28 September. Special reports issued at 1655, at 1707, at 1736, and 1813 on 22 September noted that lahars descended the El Jute (ESE), Las Lajas, Ceniza, Zarco, Mazate, Seca, and Mineral (W) drainages. The lahars that descended the El Jute and Las Lajas drainages were hot and had a sulfur odor.
On 23 September lahars descended the Santa Teresa, El Jute, Ceniza, and possibly the Las Lajas based on reports from 1410, 1440, and 1500. Reports issued at 1530 and 1601 on 25 September noted that lahars traveled down the Seca, Mineral, Ceniza, Zarco, and Mazate drainages. Lahars descended the Ceniza, Zarco, and Mazate drainages the next day based on a report from 1940 on 28 September.
All of the lahars were characterized as a mixture of water and sediment that carried tree branches, trunks, and blocks as large as 3 m in diameter.

Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
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From: Global Volcanism Program, 2025. Report on Fuego (Guatemala). In: Mayberry, G (ed.), Weekly Volcanic Activity Report 1 October-7 October 2025. Smithsonian Institution and US Geological Survey.

Suwanosejima volcano (Japan) - Smithsonian / USGS Weekly Volcanic Activity Report for 24 September-30 September 2025 (Continuing Activity)
Oct 9 2025 at 6:00 am EDT

The Japan Meteorological Agency (JMA) reported that eruptive activity at Suwanosejima's Ontake Crater continued during 22-29 September. Incandescence was observed nightly in webcam images. Eruptive events during 23-28 September generated ash plumes that rose 1-1.6 km above the crater rim and drifted mainly N, NW, and E.
Small amounts of ashfall were reported in Toshima Village (3.5 km SSW) on 27 September. Ash emissions were continuous from 2238 on 27 September to 0100 on 28 September. The Alert Level remained at 2 (the second level on a five-level scale) and the public was warned to be cautious within 1.5 km of the crater.

Source: Japan Meteorological Agency (JMA)
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From: Global Volcanism Program, 2025. Report on Suwanosejima (Japan). In: Mayberry, G (ed.), Weekly Volcanic Activity Report 1 October-7 October 2025. Smithsonian Institution and US Geological Survey.

Merapi volcano (Indonesia) - Smithsonian / USGS Weekly Volcanic Activity Report for 24 September-30 September 2025 (Continuing Activity)
Oct 9 2025 at 6:00 am EDT

The Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG) reported that the eruption at Merapi (on Java) continued during 19-25 September. The SW lava dome produced 5 lava avalanches that traveled as far as 2 km SW down the Bebeng drainage, 37 that traveled as far as 2 km SW down the Krasak drainage, and 46 that traveled as far as 2 km W down the Sat/Putih drainage. Small morphological changes to the SW lava dome resulted from lava effusion and minor collapses.
The Alert Level remained at 3 (on a scale of 1-4), and the public was warned to stay 3-7 km away from the summit, based on location.

Source: Antara News
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From: Global Volcanism Program, 2025. Report on Merapi (Indonesia). In: Mayberry, G (ed.), Weekly Volcanic Activity Report 1 October-7 October 2025. Smithsonian Institution and US Geological Survey.

Semeru volcano (Indonesia) - Smithsonian / USGS Weekly Volcanic Activity Report for 24 September-30 September 2025 (Continuing Activity)
Oct 9 2025 at 6:00 am EDT

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that activity continued at Semeru during 24-30 September, with daily eruptive events recorded by the seismic network. Daily white-and-gray or gray ash plumes rose 400-900 m above the summit and drifted in multiple directions. The Alert Level remained at 2 (the second lowest level on a scale of 1-4).
The public was warned to stay at least 3 km away from the summit in all directions, 8 km from the summit to the SE, 500 m from the banks of the Kobokan drainage as far as 13 km from the summit, and to avoid other drainages including the Bang, Kembar, and Sat, due to lahar, avalanche, and pyroclastic flow hazards.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
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From: Global Volcanism Program, 2025. Report on Semeru (Indonesia). In: Mayberry, G (ed.), Weekly Volcanic Activity Report 1 October-7 October 2025. Smithsonian Institution and US Geological Survey.

Sheveluch volcano (Russia) - Smithsonian / USGS Weekly Volcanic Activity Report for 24 September-30 September 2025 (Continuing Activity)
Oct 9 2025 at 6:00 am EDT

The Kamchatkan Volcanic Eruption Response Team (KVERT) reported continuing eruptive activity at Sheveluch’s “300 years of RAS” dome on the SW flank of Old Sheveluch and at the Young Sheveluch dome during 18-25 September. Daily thermal anomalies over the domes were identified in satellite images. Ash plumes were identified in satellite and webcam images rising to 5 km a.s.l. and drifting more than 150 km SE and NW during 18-19 September.
Plumes of resuspended ash drifted 1,700 km E and SE during 23-25 September. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Dates are based on UTC; specific events are in local time where noted.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
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From: Global Volcanism Program, 2025. Report on Sheveluch (Russia). In: Mayberry, G (ed.), Weekly Volcanic Activity Report 1 October-7 October 2025. Smithsonian Institution and US Geological Survey.

Yasur volcano (Vanuatu) - Smithsonian / USGS Weekly Volcanic Activity Report for 24 September-30 September 2025 (Continuing Activity)
Oct 9 2025 at 6:00 am EDT

The Vanuatu Meteorology and Geohazards Department (VMGD) reported that activity at Yasur continued at a level of “major unrest,” as defined by the Alert Level 2 status (on a scale of 0-5) during September. Sulfur dioxide gas emissions were identified in satellite images during 2-17 and 19-21 September, and low-level thermal anomalies were identified during 6-7, 9-12, 16-17, and 19 September. Field photos and webcam images indicated that explosions continued periodically, producing emissions of gas, steam, and/or ash during 3, 9-10, 12, 14, 16-19, 21, and 23-25 September.
Seismic data confirmed continuing volcanic activity with explosions that were occasionally strong. The report warned that ejected material from explosions could fall in and around the crater. The public was reminded to not enter the restricted area within 600 m around the boundaries of the Permanent Exclusion Zone, defined by Danger Zone A on the hazard map.

Source: Vanuatu Meteorology and Geohazards Department (VMGD)
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From: Global Volcanism Program, 2025. Report on Yasur (Vanuatu). In: Mayberry, G (ed.), Weekly Volcanic Activity Report 1 October-7 October 2025. Smithsonian Institution and US Geological Survey.

Marapi volcano (Indonesia) - Smithsonian / USGS Weekly Volcanic Activity Report for 24 September-30 September 2025 (Continuing Activity)
Oct 9 2025 at 6:00 am EDT

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity at Marapi (on Sumatra) continued during 24-30 September. Eruptive events at 1959 on 24 September and at 2116 on 26 September were recorded but weather conditions prevented visual confirmation. An eruptive event at 1831 on 26 September produced a dense white-and-gray ash plume that rose 1 km above the summit and drifted E.
The Alert Level remained at 2 (on a scale of 1-4) and the public was warned to stay 3 km away from the active crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
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From: Global Volcanism Program, 2025. Report on Marapi (Indonesia). In: Mayberry, G (ed.), Weekly Volcanic Activity Report 1 October-7 October 2025. Smithsonian Institution and US Geological Survey.

Lopevi volcano (Vanuatu) - Smithsonian / USGS Weekly Volcanic Activity Report for 24 September-30 September 2025 (Continuing Activity)
Oct 9 2025 at 6:00 am EDT

The Vanuatu Meteorology and Geohazards Department (VMGD) reported that seismic data confirmed continuing unrest at Lopevi during September. Low-level thermal anomalies were identified in satellite images during 12-13 and 17 September. Small fumarolic steam plumes were continuously emitted from the summit crater on 22 September based on webcam images.
The Alert Level remained at 2 (on a scale of 0-4).

Source: Vanuatu Meteorology and Geohazards Department (VMGD)
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From: Global Volcanism Program, 2025. Report on Lopevi (Vanuatu). In: Mayberry, G (ed.), Weekly Volcanic Activity Report 1 October-7 October 2025. Smithsonian Institution and US Geological Survey.

Krasheninnikov volcano (Russia) - Smithsonian / USGS Weekly Volcanic Activity Report for 24 September-30 September 2025 (Continuing Activity)
Oct 9 2025 at 6:00 am EDT

The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that the eruption at Krasheninnikov continued during 18-25 September. A daily large thermal anomaly over the volcano was identified in satellite images. Explosions at Northern Cone produced ash plumes that rose 2.4 km a.s.l., or nearly 600 m above the summit, and drifted 260 km SE and E during 23-25 September.
A commercial satellite image on 25 September showed that lava flows had traveled 2.9 km NW, 2.8 km NE, and 3 km ENE. The upper half of the ENE flows were incandescent along with the main vent of Northern Cone. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).
Dates and times are provided in Coordinated Universal Time (UTC); specific events are indicated in local time where specified.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Copernicus
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From: Global Volcanism Program, 2025. Report on Krasheninnikov (Russia). In: Mayberry, G (ed.), Weekly Volcanic Activity Report 1 October-7 October 2025. Smithsonian Institution and US Geological Survey.

Lewotobi volcano (Indonesia) - Smithsonian / USGS Weekly Volcanic Activity Report for 24 September-30 September 2025 (Continuing Activity)
Oct 9 2025 at 6:00 am EDT

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that daily white-and-gray or gray ash plumes with variable densities rose as high as 2 km above the summit of Lewotobi Laki-laki and drifted N, NW, W, and SW during 23-29 September. According to a news article the Fransiskus Xaverius Seda Airport (60 km W) was closed on 26 September through early 27 September; volcanic ash caused six flights to be canceled. PVMBG noted that seismic activity during the week was dominated by low-frequency earthquakes, non-harmonic tremor, and signals indicating eruptive events and emissions.
The number of explosions fluctuated at moderate levels and the number of deep volcanic earthquakes declined. Tilt data indicated inflation at shallow depths and GNSS (Global Navigation Satellite System) data showed continuing deformation. At 1500 on 29 September the Alert Level was lowered to 3 (on a scale of 1-4) and the public was warned to stay 6 km away from the center of Laki-laki.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM), Antara News
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From: Global Volcanism Program, 2025. Report on Lewotobi (Indonesia). In: Mayberry, G (ed.), Weekly Volcanic Activity Report 1 October-7 October 2025. Smithsonian Institution and US Geological Survey.

Lewotolok volcano (Indonesia) - Smithsonian / USGS Weekly Volcanic Activity Report for 24 September-30 September 2025 (Continuing Activity)
Oct 9 2025 at 6:00 am EDT

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that an eruption at Lewotolok was ongoing during 24-30 September. On most days white-and-gray ash plumes rose 100-600 m above the summit of the cone and drifted W and NW; only white plumes rising to 100 m above the summit were observed on 27 September. Several nighttime webcam images showed Strombolian ejections of incandescent material above the cone and onto the flanks.
The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
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From: Global Volcanism Program, 2025. Report on Lewotolok (Indonesia). In: Mayberry, G (ed.), Weekly Volcanic Activity Report 1 October-7 October 2025. Smithsonian Institution and US Geological Survey.

Klyuchevskoy volcano (Russia) - Smithsonian / USGS Weekly Volcanic Activity Report for 24 September-30 September 2025 (Continuing Activity)
Oct 9 2025 at 6:00 am EDT

The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that wind was no longer resuspending ash previously deposited on the N flank of Klyuchevskoy. Only fumarolic emissions were observed. The Aviation Color Code was lowered to Green (the lowest level on a four-color scale) on 25 September.
Dates and times are provided in Coordinated Universal Time (UTC); specific events are indicated in local time where specified.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
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From: Global Volcanism Program, 2025. Report on Klyuchevskoy (Russia). In: Mayberry, G (ed.), Weekly Volcanic Activity Report 1 October-7 October 2025. Smithsonian Institution and US Geological Survey.