Ahyi (United States) | 23 July-29 July 2025 | Continuing ActivityCite this Report

At 1047 on 24 July both the Aviation Color Code and the Volcano Alert Level for Ahyi Seamount were lowered to Unassigned because signs of unrest had declined, and discolored seawater over the seamount was last observed on 28 May. The latest phase of activity began in August 2024 and was characterized by visible plumes of discolored seawater observed sporadically in satellite images.

Source: US Geological Survey

Aira (Japan) | 23 July-29 July 2025 | Continuing ActivityCite this Report

The Japan Meteorological Agency (JMA) reported ongoing eruptive activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 21-28 July. Occasional very small eruptive events occurred during 21-25 July. Crater incandescence was visible during 22-23 and 27 July. An explosion at 1243 on 27 July generated a small ash plume that rose 800 m above the crater rim and drifted NW. Another small ash plume from an explosion at 0716 on 28 July rose 500 m above the crater rim and drifted W. 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)

Asosan (Japan) | 23 July-29 July 2025 | Continuing ActivityCite this Report

The Japan Meteorological Agency (JMA) reported that unrest at Asosan had decreased. The amplitude of volcanic tremors had increased during 4-7 July but then returned to low levels afterward. During field surveys on 16 and 23 July scientists observed no changes compared to field surveys conducted before the increased tremor amplitude. Sulfur dioxide gas emissions were low in July, averaging 200-500 tons per day. At 1100 on 25 July the Alert Level was lowered to 1 (on a scale of 1-5).

Source: Japan Meteorological Agency (JMA)

Dukono (Indonesia) | 23 July-29 July 2025 | Continuing ActivityCite this Report

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity at Dukono continued during 23-29 July. White-and-gray gas-and-ash plumes rose 700-3,500 m above the summit and drifted in multiple directions on most days; weather conditions obscured views on 26 July. Ashfall was reported from Ruko (11 km NW) to Tobelo City (15 km ENE) on 24 July, and in Mamuya Village (8 km N) and surrounding areas on 26 and 28 July. 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)

Etna (Italy) | 23 July-29 July 2025 | Continuing ActivityCite this Report

The Sezione di Catania - Osservatorio Etneo (INGV) reported various gas emissions from Etna’s summit craters during 21-27 July. Sporadic ash emissions rose from SE Crater during the week. On 25 July notably intense gas emissions rose from a vent on the NE Crater floor on and gas emissions rose from several fumarolic vents along the SE Crater flanks and near the summit

Source: Sezione di Catania - Osservatorio Etneo (INGV)

Fuego (Guatemala) | 23 July-29 July 2025 | Continuing ActivityCite this Report

The Instituto Nacional de Sismología, Vulcanologia, Meteorologia e Hidrología (INSIVUMEH) reported that eruptive activity at Fuego continued during 22-29 July. Incandescence at the summit was occasionally observed in overnight webcam images. Pulses of gas and ash were visible during 22-23 and 26-27 July; the plumes drifted W and SE during 26-27 July. A lahar descended the Ceniza (SSW) drainages on 25 July. Avalanches of material that descended the Seca (W) drainage during 26-27 July.

Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)

Great Sitkin (United States) | 23 July-29 July 2025 | Continuing ActivityCite this Report

The Alaska Volcano Observatory (AVO) reported that slow lava effusion continued to feed a thick flow in Great Sitkin’s summit crater during 23-29 July. Lava flow advancement was concentrated at the SW lobe, which advanced 5 m during 20-23 July and continued to inflate. Small daily earthquakes were detected by the seismic network, including signals probably caused by small rockfalls from the steep flanks. Elevated surface temperatures consistent with lava effusion were observed in clear satellite views during 22-23 and 25-28 July. Minor steaming at the flow was visible in both webcam and satellite images during 28-29 July. 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)

Ibu (Indonesia) | 23 July-29 July 2025 | Continuing ActivityCite this Report

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that the eruption at Ibu continued during 23-29 July. Daily dense gray or white-to-gray ash plumes rose 200-800 m above the summit and drifted NW, NE, and SE. Crater incandescence was visible in 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)

Kanlaon (Philippines) | 23 July-29 July 2025 | Continuing ActivityCite this Report

At 1830 on 29 July the Philippine Institute of Volcanology and Seismology (PHIVOLCS) lowered the Alert Level for Kanlaon to 2 on a scale of 0-5) noting declining activity after the 13 May eruption. Volcanic earthquakes recorded by the seismic network averaged eight events per day during 14 May-29 July, fewer than the average of 14 events per day during 3 June 2024-13 May 2025. Volcano-tectonic earthquakes continued to be detected and were located mostly 0-15 km below the surface along a NW-SE transect though the edifice. Despite the decline in average events per day, overall seismic energy represented by RSAM values had not significantly decreased. An ash plume was observed on 5 June, but afterwards only gas-and-steam plumes were seen rising from the summit crater. Sulfur dioxide emissions had decreased to an average of 1,857 tonnes per day during 14 May-29 July. A low rate of inflation had been detected by continuous Global Positioning System (GPS) and Electronic Distance Measurement (EDM) data since 2022, though deflation was detected during the last week of June and the first week of July. PHIVOLCS urged communities to remain evacuated from the 4-km-radius Permanent Danger Zone (PDZ).

Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS)

Karymsky (Russia) | 23 July-29 July 2025 | Continuing ActivityCite this Report

The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that moderate steam-and-gas activity continued at Karymsky during 18-24 July. A weak thermal anomaly over the volcano was identified in satellite images during 19-21 July; the volcano was quiet or weather conditions prevented views on the other days of the week. At 1100 on 25 July the Aviation Color Code was lowered to Yellow (the second 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)

Kilauea (United States) | 23 July-29 July 2025 | Continuing ActivityCite this Report

The Hawaiian Volcano Observatory (HVO) reported that the eruption within Kilauea’s Kaluapele summit caldera, characterized by episodic fountaining and intermittent spatter at two vents along the SW margin of Halema’uma’u Crater, continued at variable levels during 23-29 July. Intermittent incandescence at the N vent was visible during the first half of the week and absent starting overnight during 26-27 July. Incandescence at two areas higher up on the eruptive cone was intermittent and became less intense through the week. Seismic and gas data indicated that gas pistoning occurred as often as every 3-5 minutes; however, no lava or spatter was visible at the surface in association with the activity. 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)

Lewotolok (Indonesia) | 23 July-29 July 2025 | Continuing ActivityCite this Report

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that an eruption at Lewotolok was ongoing during 23-29 July. White-to-gray or gray ash plumes rose 200-500 m above the summit of the cone and drifted W, NW, and SE; weather conditions obscured views on 29 July. Clear nighttime webcam images showed incandescent material being ejected above the cone. 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)

Marapi (Indonesia) | 23 July-29 July 2025 | Continuing ActivityCite this Report

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity at Marapi (on Sumatra) continued during 23-29 July. An explosion at 0723 on 23 July produced a dense white-and-gray ash plume that rose around 1.6 km and drifted SE. According to a news report residents in the Ampek Angkek District (12 km NNW) heard a loud explosion and felt their houses shake. Eruptive events were recorded by the seismic network at 1730 on 25 July and at 1344 on 27 July, but weather clouds obscured visual confirmation. 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.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM), Antara News

Merapi (Indonesia) | 23 July-29 July 2025 | Continuing ActivityCite this Report

The Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG) reported that the eruption at Merapi (on Java) continued during 18-24 July. Earthquakes were more intense compared to the previous week. The SW lava dome produced 15 lava avalanches that traveled as far as 1.8 km SW down the Bebeng drainage, 24 that traveled as far as 2 km SW down the Krasak drainage, 70 that traveled as far as 2 km W down the Sat/Putih drainage, and one that descended the Boyong drainage on the S flank as far as 1.5 km. Small morphological changes to the SW lava dome resulted from minor collapses. The volume of the SW dome decreased by 66,700 cubic meters to an estimated 4,011,000 cubic meters, based on webcam images and a 17 July drone survey and webcam images. The temperature of the dome had increased by 2.8 degrees Celsius (degrees C) to 244.9 degrees C. The volume of the central dome increased by about 1,600 cubic meters to an estimated 2,368,900 cubic meters, though no morphological changes were observed. The temperature increased by 3.5 degrees C to 218.6 degrees C. 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: Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG)

Poas (Costa Rica) | 23 July-29 July 2025 | Continuing ActivityCite this Report

The Observatorio Vulcanológico y Sismológico de Costa Rica-Universidad Nacional (OVSICORI-UNA) reported continuing gas-and-steam emissions with occasional minor amounts of ash at Poás during 23-29 July. Strong incandescence at Boca A vent was observed and the level of the hyperacid lake over Boca C remained at stable levels. Dense gas-and-steam emissions continued to be emitted from both Boca A and Boca C vents. On 24 July the Comisión Nacional de Emergencias (CNE) conducted an overflight of the crater using a drone with an infrared camera and measured a maximum temperature of 819 degrees Celsius over Boca A and 74-87 degrees Celsius at the lake over Boca C. They observed highly altered pinkish-yellow rocks at the rim of Boca A and down in the crater. Sulfur dioxide emissions measured by satellite averaged 37 tons per day (t/d) during 20-24 July and 520 t/d on 26 July. A moderate eruption that began at 0244 on 27 July lasted for three minutes, producing ash emissions and ejecting incandescent blocks 1 km above the crater floor. The Comisión Nacional de Emergencias (CNE) lowered the Alert Level to Green for Parque Nacional Volcán Poás and district of Toro Amarillo in the Canton of Sarchí (including the Desagüe, Agrio, Anonos, and Gorrión river basins) on 2 July due to decreasing activity and then lifted the Green Alert for the park and surrounding areas on 23 July. The volcanic Alert Level remained at 2 (the second lowest level on a four-level scale) and the Aviation Color Code remained at Yellow (the second lowest color on a four-color scale).

Sources: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA), Comisión Nacional de Prevención de Riesgos y Atención de Emergencias (CNE)

Santa Maria (Guatemala) | 23 July-29 July 2025 | Continuing ActivityCite this Report

The Instituto Nacional de Sismología, Vulcanología, Meteorología e Hidrología (INSIVUMEH) reported high levels of ongoing eruptive activity at Santa Maria’s Santiaguito dome complex during 22-29 July with continuing lava extrusion at Caliente dome. Daily explosions, 1-5 per hour when reported, generated gas-and-ash plumes that rose as high as 1 km above the dome and drifted as far as 20 km W and SW. Effusion of blocky lava and collapses of previous deposits produced block avalanches that descended multiple flanks; the collapsed material sometimes produced pyroclastic flows that reached the base of the volcano. Incandescence was visible at Caliente dome mostly during dark hours. On 25 July a minor lahar descended the Cabello de Ángel river, a tributary of the Nimá I, on the E flank, carrying tree trunks, branches, and volcanic blocks up to 3 m in diameter. The lahar was hot and has a sulfur odor. Minor ashfall was reported in communities to the S and SW during 25-26 July.

Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)

Semeru (Indonesia) | 23 July-29 July 2025 | Continuing ActivityCite this Report

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that activity continued at Semeru during 23-29 July, often with multiple daily eruptive events recorded by the seismic network. Dense white-and-gray or gray ash plumes rose 500-1,000 m above the summit and drifted in multiple directions; weather clouds occasionally obscured views, particularly during 25 and 28-29 July. Incandescence at the summit was visible in a few webcam images; incandescent material traveling down the flank was visible at 2049 on 26 July in a webcam image. 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)

Sheveluch (Russia) | 23 July-29 July 2025 | Continuing ActivityCite this Report

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 17-24 July. Thermal anomalies over the domes were identified in satellite images all week. According to the Kamchatka Volcanological Station (Volkstat) minor ash plumes were visible on 22 July; no dome growth was observed. Explosions on 23 July produced ash plumes that rose as high as 3 km (10,000 ft) a.s.l. and drifted 70 km E. 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.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Kamchatka Volcanological Station

Suwanosejima (Japan) | 23 July-29 July 2025 | Continuing ActivityCite this Report

The Japan Meteorological Agency (JMA) reported that eruptive activity at Suwanosejima's Ontake Crater continued during 21-28 July. Incandescence was observed nightly in webcam images. An explosion at 0452 on 21 July generated an ash plume that rose 900 m above the crater rim and drifted W. Another explosion was recorded at 1209 on 24 July, though conditions prevented visual confirmation. 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)