Active volcanoes, clearly explained.

Kīlauea is not erupting. Episode 54 ended on 25 August after nine hours of continuous north-vent lava fountaining. HVO's 27 August update says summit reinflation has stopped and variable deflation is continuing. Another lava-fountaining episode may occur in coming weeks if normal tilt patterns resume, but HVO says more data are needed before a forecast window can be modelled.

Fuego remains in its normal persistent eruptive pattern. INSIVUMEH's 23 August ash-dispersion update reported gas-and-ash columns reaching 4,300–4,700 m above sea level and dispersing about 50 km north; its seismic records did not indicate an increase in activity.

No eruption is underway. IMO's 18 August update reports slow, steady uplift and magma accumulation beneath Svartsengi, low seismicity, and an estimated 29.1 million m³ of magma accumulated since the July 2025 eruption. IMO says a future intrusion toward the Sundhnúkur crater row, potentially followed by an eruption, remains the most likely scenario and warning time could be short.

Campi Flegrei remains under Yellow — Attention status. INGV-OV published its latest weekly Campi Flegrei monitoring bulletin on 25 August; the system remains under close monitoring for bradyseism, seismicity, deformation and hydrothermal parameters.

INGV-OE issued an end-of-phenomenon notice on 26 August, stating that the previously reported eruptive phenomena had ended. The VONA issued that morning returned Etna to Aviation Colour Code GREEN; the Smithsonian/USGS weekly report, citing INGV and Italian Civil Protection, also records the change to GREEN on 26 August.

Ordinary Strombolian explosive activity continues at the summit crater areas. INGV-OE's latest multidisciplinary weekly bulletin for Stromboli was published on 25 August.

Popocatépetl remains at Yellow Phase 2. CENAPRED's 27 August report recorded four low-intensity exhalations accompanied by water vapour, volcanic gases and light ash, plus one volcano-tectonic earthquake of M1.6. The 12 km exclusion zone remains in force.

Sakurajima remains at Volcanic Alert Level 3, but recent activity has been relatively quiet. JMA reported only occasional very small eruptions at Minamidake during 21–24 August and no explosions during that period. Ground-deformation instruments began recording inflation of the edifice on 23 August, which was still continuing when JMA issued the 24 August update.

No eruption is underway. OVPF-IPGP's preliminary bulletin for 26 August keeps Piton de la Fournaise at Vigilance. No summit or deep volcano-tectonic earthquakes were recorded that day.

Yellowstone remains at background activity. YVO's 1 August monthly update reports 68 located earthquakes during July, with the largest M3.3, and only minor caldera uplift since the start of 2026.

Slow eruption of lava within Great Sitkin's summit crater continues. AVO's 27 August update reports minor earthquakes during the previous day; cloudy satellite and webcam views prevented useful visual observations. AVO says the current lava eruption began in July 2021.

Mount St. Helens remains at normal background activity. CVO's 21 August weekly update keeps all Cascade Range volcanoes in Washington and Oregon at NORMAL / GREEN; small earthquakes were detected at Mount St. Helens and Mount Rainier during that week, with all monitoring data consistent with background activity.

Mount Rainier remains at normal background activity. CVO's 21 August weekly update keeps all Cascade Range volcanoes in Washington and Oregon at NORMAL / GREEN; small earthquakes were detected at Mount Rainier and Mount St. Helens during that week, with all monitoring data consistent with background activity.

Mayon remains at Alert Level 2 (Decreased Unrest). PHIVOLCS' 28 August bulletin records one weak ash-explosion event lasting one minute, 15 volcanic earthquakes, a moderate plume reaching 500 m above the crater, and sulfur dioxide flux of 5,878 tonnes/day measured on 27 August. The 6 km Permanent Danger Zone remains off-limits.

Merapi remains at Level III (Siaga). Official PVMBG/BPPTKG reporting continues to describe active lava-dome growth and lava avalanches, with pyroclastic-density-current hazards concentrated in the established hazard sectors.

Kanlaon remains at Alert Level 2 (Increased Unrest). PHIVOLCS' 28 August bulletin records no volcanic earthquakes in the previous 24 hours, a moderate plume reaching 200 m above the crater, sulfur dioxide flux of 721 tonnes/day on 27 August, and continuing inflation of the edifice with short-term deflation. The 4 km Permanent Danger Zone remains prohibited.

Taal remains at Alert Level 1 (Low-level Unrest). PHIVOLCS' 28 August bulletin records 18 volcanic earthquakes, including one volcanic tremor lasting 504 minutes, weak plume emission, sulfur dioxide flux of 381 tonnes/day on 27 August, and short-term inflation of Taal Volcano Island.

Poás remains at OVSICORI-UNA activity Level 2 (Warning) in the latest detailed official Poás communication located for this review. That 30 April update described instability of the shallow system and said further eruptions involving ash, gas and ballistic material around the crater could occur.

Eruptive activity continued during 20–26 August. PVMBG reported white-and-gray ash plumes rising as high as 1.4 km above the summit. Alert Level remained II and the 4 km exclusion zone around Malupang Warirang Crater remained in force.

Eruptive activity continued during 20–26 August, with daily eruptive events and ash plumes rising about 300–1,000 m above the summit. PVMBG kept Ibu at Level II with the established exclusion distances around the active crater.

Eruptive activity continued during 20–26 August. PVMBG reported incandescent ejecta and active lava flows, including a 1.2 km flow on the south flank and about 500 m on the northeast flank; an ash plume on 24 August rose about 400 m above the summit. Alert Level remained II.

Semeru remained at Level III (Siaga) during the latest verified reporting period. PVMBG reported daily eruptive events during 20–26 August, with ash plumes rising about 400–1,100 m above the summit and occasional summit incandescence.

Shishaldin remains at ADVISORY / YELLOW. AVO's 27 August update reports continued minor seismic activity; no activity was observed through cloudy satellite and webcam views, while sulfur dioxide emissions were detected by satellite.

Ruapehu remains at Volcanic Alert Level 1 and Aviation Colour Code Green. GeoNet's latest bulletin says volcanic tremor decreased from moderate to weak, with minimal change in measured gas emissions or Te Wai ā-moe (Crater Lake) temperature.

IGN's July 2026 Canary Islands monitoring summary located 611 earthquakes in central Tenerife, mainly within the Las Cañadas del Teide complex. IGN continues 24/7 seismic and deformation monitoring; the July report does not declare an eruption.

San Miguel (Chaparrastique) remains under national monitoring. No recent MARN eruptive-escalation bulletin was located during this 28 August review, so this card does not infer a current increase or eruption.

The latest official Colima state civil-protection bulletin located for this review covers 21–27 July. It reported one low-intensity explosion, five small lahars and intermittent summit degassing, describing the volcano as being in a phase of passive degassing with some low-intensity explosions. A 6 km exclusion zone remained in force.

Aso remains at Volcanic Alert Level 3. JMA's latest detailed update located for this review, issued 24 August, says volcanic tremor remained generally low but magma accumulation at depth was still indicated by GNSS, and an eruption affecting an area within roughly 2 km of Nakadake First Crater remained possible.

Vesuvius remains at Green / base level in the official Italian alert system. INGV-OV continues routine monitoring; no official alert-level escalation was identified in the current material reviewed for this update.

Nevado del Ruiz remains at Yellow alert. SGC's latest weekly bulletin covers activity from 18–24 August and retains the Yellow alert status.