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).
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.
A mud volcano at Jarawa Creek, Baratang Island, Andaman and Nicobar Islands, erupted at around 11:00 LT (05:30 UTC) on October 2, 2025, after lying dormant for two decades. The eruption released mud, gases, and water across more than 1 000 m2 (10 760 ft2), forming a mound about 3–4 m (10–13 feet) high.
New activity/unrest was reported for two volcanoes from September 24–30, 2025. During the same period, ongoing activity was reported for 22 volcanoes.
Episode 34 of the ongoing Kīlauea eruption ended at 07:03 HST (17:03 UTC) on October 1, 2025, after 6 hours of lava fountaining from two vents in Halemaʻumaʻu crater at the volcano’s summit, Hawaii. Lava fountains reached up to 400 m (1 300 feet), erupting about 9 million m³ of lava at a peak effusion rate of 500 yd³/s. The eruption filled much of the western crater floor before activity ceased.
The Japan Meteorological Agency (JMA) raised the Alert Level for Meakandake volcano in Hokkaido, Japan, from 1 to 2 at 06:20 UTC (15:20 JST) on September 15, 2025, after an increase in seismicity near Ponmachineshiri Crater. From September 16 to 23, eruptive activity continued with 27–50 daily volcanic earthquakes, minor ashfall, and white steam-and-gas plumes rising 200–800 m (656–2 625 feet) above the crater rim. Access within 500 m (1 640 feet) of the crater remains restricted, affecting parts of Kushiro City and Ashoro Town.
New activity/unrest was reported for 6 volcanoes from September 17 to 23, 2025. During the same period, ongoing activity was reported for 23 volcanoes.
A minor eruption was reported at Barren Island volcano in the Andaman Sea at around 10:15 LT (04:45 UTC) on September 20, 2025, two days after a shallow M4.2 earthquake in the region. The National Centre for Seismology suggested the quake may have disturbed the magma system, although no independent confirmation of the link is available.
A new eruptive episode started at Kīlauea’s Halemaʻumaʻu crater at 13:11 UTC (03:11 HST) on September 19, 2025, producing lava fountains over 150 m (500 feet) and a volcanic plume up to 3 000 m (10 000 feet) high. The eruption remains confined to the summit caldera within Hawaiʻi Volcanoes National Park.
Kīlauea summit, Hawaii, is showing strong gas pistoning and overflows ahead of the next eruptive episode, with Pele’s hair and volcanic gas already affecting the summit area and nearby communities. The Hawaiian Volcano Observatory (HVO) warns that episode 33 lava fountaining is expected to begin over the next 1 to 3 days.
