Aira (Japan) | 2 July-8 July 2025 | Continuing ActivityCite this Report

The Japan Meteorological Agency (JMA) reported ongoing eruptive activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 30 June-7 July. Nightly crater incandescence was visible in webcam images. One small eruptive event was recorded on 30 June. On 2 July sulfur dioxide emissions were slightly high, averaging 1,500 tons per day. Eruptive events during 6-7 July produced ash plumes that rose as high as 3 km above the crater rim. Plumes were continuously emitted during 1346-2310 on 6 July and during 0224-0840 on 7 July. 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) | 2 July-8 July 2025 | Continuing ActivityCite this Report

The Japan Meteorological Agency (JMA) reported that the amplitude of volcanic tremors at Asosan began to increase at around 1150 on 4 July, signaling an increasing unrest. Sulfur dioxide gas emissions were low, averaging 300-600 tons per day. White plumes rose 300 m above the crater rim. At 1300 the Alert Level was raised to 2 (on a scale of 1-5) and the public was warned to stay at least 1 km away from Nakadake Crater.

Source: Japan Meteorological Agency (JMA)

Dukono (Indonesia) | 2 July-8 July 2025 | Continuing ActivityCite this Report

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity at Dukono continued during 2-8 July. Daily white-and-gray or gray-to-black gas-and-ash plumes rose 600-1,600 m above the summit and drifted NW and E. Faint booming and rumbling was heard by residents and at the observation post, 10-11 km N, during 4-5 July. Ashfall was reported in areas downwind including at the Mamuya Village Observation post and in Tobelo City (15 km ENE); more ash fell in areas of Tobelo City during 6-7 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)

Great Sitkin (United States) | 2 July-8 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 2-8 July. Lava-flow advancement was concentrated at the SW and SE margins based on a 3 July radar image. Small daily earthquakes were detected by the seismic network, including signals probably caused by small rockfalls from the steep flanks. Slightly elevated surface temperatures consistent with lava effusion were observed in clear satellite views during 1-2 and 4-5 July. Diffuse steaming from the known active portions of the lava flow was observed in satellite images during 7-8 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)

Home Reef (Tonga) | 2 July-8 July 2025 | Continuing ActivityCite this Report

The Tonga Geological Services reported that activity at Home Reef continued during 21 June-5 July. Discolored water around the island was visible in clear satellite images on 26 June and 1 July. The crater was about 210 m N-S and 120 m E-W. Fresh dark deposits surrounded the vent in the first image and lighter deposits around the same area were visible in the second image. The activity could not be accurately characterized due to the images being low resolution. No thermal anomalies nor ash emissions were detected in satellite data. The Aviation Color Code remained at Yellow (the second lowest level on a four-level scale, the Maritime Alert Level remained at Orange (the third level on a four-level scale) with advice to stay at least 2 nautical miles (3.7 km) from the island, and the Alert Level for residents of Vava’u and Ha’apai remained at Green (the first level on a four-level scale).

Source: Tonga Geological Services, Government of Tonga

Ibu (Indonesia) | 2 July-8 July 2025 | Continuing ActivityCite this Report

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that the eruption at Ibu continued during 2-8 July. Daily dense gray or white-to-gray ash plumes rose 300-700 m above the summit and drifted in multiple directions. Nighttime crater incandescence was visible in some webcam images. The Alert Level remained at 3 (the second highest level on a four-level scale) and the public was advised to stay 4 km away from the active crater and 5 km away from the N crater wall opening.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)

Kilauea (United States) | 2 July-8 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 2-8 July. Nighttime incandescence at the N vent was visible every night, with intermittent lava spattering and jetting at the same vent visible during 3-7 July. Rockfalls from spatter deposits on the crater wall exposed areas of incandescence. Two short overflows of lava at the N vent occurred at around 1830 on 7 July. Cycles of minor lava spattering, lava jetting, and gas flames were visible during 7-8 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 Hawaiian Volcano Observatory (HVO)

Marapi (Indonesia) | 2 July-8 July 2025 | Continuing ActivityCite this Report

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity at Marapi (on Sumatra) continued during 2-8 July. Daily white plumes rose as high as 150 m above the summit and drifted NE, E, and SE. An eruptive event was recorded at 1359 om 6 July though not visually observed. 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)

Merapi (Indonesia) | 2 July-8 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 27 June-3 July. Seismic levels were similar to the previous week. The SW lava dome produced eight lava avalanches that traveled as far as 2 km SW down the Bebeng drainage, five that traveled as far as 1.5 km SW down the Krasak drainage, and 56 that traveled as far as 2 km W down the Sat/Putih drainage. Small morphological changes to the SW lava dome resulted from continuing 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: Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG)

Poas (Costa Rica) | 2 July-8 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 2-8 July. Uplift ceased to be detected in the past few weeks and no significant deformation was detected during the current week. Strong incandescence at Boca A vent was observed and the level of the hyperacid lake over Boca C had stabilized. Minor ashfall was reported in areas downwind on 3 July. The 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).

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

Rainier (United States) | 2 July-8 July 2025 | Continuing ActivityCite this Report

The Cascades Volcano Observatory (CVO) reported that a small seismic swarm at Rainier began at 0129 on 8 July. By the 0926 the seismic network recorded hundreds of earthquakes at rates up to several per minute. The earthquakes were located at depths of 2-6 km below the summit; the largest earthquake, a M 1.7, was detected at 0452. No earthquakes were felt, no deformation was detected, and no anomalous signals were detected at infrasound monitoring stations. CVO noted that seismicity is typically about 9 earthquakes per month, plus swarms once or twice per year, but with much smaller numbers of events per swarm. The last large swarm at Rainier had over 1,000 earthquakes over three days in 2009 (120 located), had an earthquake with a maximum magnitude of 2.3. Past swarms have been attributed to circulation of fluids interacting with preexisting faults. 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 color on a four-color scale).

Source: US Geological Survey Cascades Volcano Observatory (CVO)

Raung (Indonesia) | 2 July-8 July 2025 | Continuing ActivityCite this Report

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity at Raung continued during 2-8 July. Gray or white-and-gray ash plumes rose 400-1,000 m above the crater rim and drifted S and SW during 2, 4-5, and 7 July. Incandescence at the summit was sometimes visible in webcam images. The Alert Level remained at 2 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)

Reventador (Ecuador) | 2 July-8 July 2025 | Continuing ActivityCite this Report

The Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN) reported that eruptive activity continued at Reventador during 1-8 July. Seismicity included 70-112 daily explosions, long-period earthquakes, harmonic tremor, and tremor associated with emissions. Multiple daily ash-and-gas plumes rose 400-700 m above the crater rim and drifted mainly NW, W, and SW. Webcams recorded multiple nightly instances of incandescent material descending the flanks as far as 1.1 km below the crater rim. Secretaría de Gestión de Riesgos (SGR) maintained the Alert Level at Orange (the second highest level on a four-color scale).

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN), Secretaría de Gestión de Riesgos (SGR)

Sangay (Ecuador) | 2 July-8 July 2025 | Continuing ActivityCite this Report

The Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN) reported that the eruption continued at Sangay during 1-8 July. The seismic network recorded 48-94 explosions each day. Ash-and-gas plumes were observed in webcam and/or satellite images rising as high as 1.2 km above the summit and drifting mainly, NW, W, and SW, though weather clouds sometimes obscured views; plumes were not observed during 3-4 July. The surveillance camera network recorded several instances of incandescent material descending the flanks as far as 1 km during 5-7 July. Secretaría de Gestión de Riesgos (SGR) maintained the Alert Level at Yellow (the second highest level on a four-color scale).

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN), Secretaría de Gestión de Riesgos (SGR)

Semeru (Indonesia) | 2 July-8 July 2025 | Continuing ActivityCite this Report

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that activity continued at Semeru during 2-8 July, often with multiple daily eruptive events recorded by the seismic network. Emissions were not visually observed most of the week. Dense white-and-gray ash plumes rose 400-1,000 m above the summit and drifted NE, N, W, and SW during 2 and 6-7 July. 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)

Suwanosejima (Japan) | 2 July-8 July 2025 | Continuing ActivityCite this Report

The Japan Meteorological Agency (JMA) reported that eruptive activity at Suwanosejima's Ontake Crater continued during 30 June-7 July. Incandescence was observed nightly in webcam images. Six explosions were recorded during the week, at 0806 on 30 July, at 0752 and 1608 on 1 July, at 0206 on 2 July, and at 1327 and 2038 on 6 July. The explosions produced ash plumes that rose as high as 2 km above the crater rim and drifted W, SE, and E; some of the plumes were not visible. Ashfall was reported by the Suwanosejima Branch of the Toshima Village Office (3.5 km SSW) on 30 June and 6 July. Eruptive events during 30 June and 6-7 July generated ash plumes that rose as high as 2 km above the crater rim and drifted W, SE, and E. 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)

Taal (Philippines) | 2 July-8 July 2025 | Continuing ActivityCite this Report

The Philippine Institute of Volcanology and Seismology (PHIVOLCS) reported increased seismicity at Taal. No volcanic earthquakes were recorded by the seismic network during 1-4 July, but two low-frequency volcanic earthquakes were detected on 5 July. A distinct increase in volcanic tremor began at 0337 on 6 July and continued at elevated levels through the day. Low levels of sulfur dioxide had been emitted in June with daily averages of 478 tonnes per day (t/d) on 2 July and 377 t/d on 4 July. Daily gas-and-steam emissions rose as high as 1.8 km above the crater rim and drifted mainly NE, though emissions became noticeably absent around the same time as increased seismicity. PHIVOLCS warned that the increased seismicity and lack of emissions may indicated a blockage and increased pressurization, potentially leading to a phreatic event. The Alert Level remained at 1 (on a scale of 0-5); PHIVOLCS reminded the public that the entire Taal Volcano Island (TVI) was a Permanent Danger Zone (PDZ) and recommended that the Main Crater and areas along the Daang Kastila fissure should remain prohibited. Pilots were warned to avoid flying over TVI.

Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS)

Yellowstone (United States) | 2 July-8 July 2025 | Continuing ActivityCite this Report

The Yellowstone Volcano Observatory (YVO) reported that a small hydrothermal eruption occurred at Black Diamond Pool, in Yellowstone’s Biscuit Basin thermal area, at 2018 on 3 July based on webcam images. 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 color on a four-color scale).

Source: Yellowstone Volcano Observatory (YVO)