The Weekly Volcanic Activity Report: June 25–July 1, 2025
New activity/unrest was reported for two volcanoes from June 25 to July 1, 2025. During the same period, ongoing activity was reported for 20 volcanoes.
Madre Fire explodes to over 14 000 ha (35 500 acres) in one day, becoming California’s largest wildfire of 2025
The Madre Fire in California’s San Luis Obispo County ignited around 13:00 LT on July 2, 2025, and burned through 14 370 ha (35 531 acres) by early July 3. Evacuation orders and warnings have been issued for multiple zones as strong winds and high temperatures continue to fuel rapid fire growth. This is the largest wildfire in California in 2025 to date.
Horse Fire grows to 160 ha (400 acres) west of Lakehead, California after intense lightning storm
A lightning-sparked Horse Fire, located west of Lakehead, California, has burned about 160 ha (400 acres) near Schell Mountain, south of Clear Creek Campground, as of July 3, 2025. Fire crews have made progress on containment, and the fire has not crossed Rattlesnake Creek.
Explosive eruption at Shinmoedake blankets parts of Miyazaki and Kagoshima prefectures with ash, Japan
A strong explosive eruption occurred at Shinmoedake volcano, part of the Kirishima volcanic complex on Kyushu Island, Japan, at approximately 15:37 JST (06:37 UTC) on July 3, 2025, sending an ash plume up to 6.7 km (22 000 feet) above sea level (a.s.l.). The Japan Meteorological Agency (JMA) had raised the volcanic alert to Level 3 on June 27, following increased volcanic unrest.
4 hospitalized and nearly 1 500 evacuated as a major wildfire burns through Ierapetra in Crete, Greece
At least 4 people have been hospitalized and nearly 1 500 people have been evacuated as firefighters continued to engage a major wildfire on the Greek island of Crete on Thursday, July 3, 2025.
Early-summer heatwave claims 8 lives across Europe
At least eight people have died across Spain, France, and Italy as an early-summer heatwave swept across Europe in late June and early July 2025, breaking temperature records and prompting red alerts and emergency responses.
Record marine heatwave pushes Mediterranean Sea surface temperatures to 30°C (86°F) off Spain
Sea surface temperatures in the western Mediterranean Sea reached up to 30 °C (86 °F) in early July 2025, with anomalies of 5–6 °C (9–10.8 °F) above average under strong to severe marine heatwave conditions.
Argentina closes border crossing as record-breaking polar wave sweeps across Chile
Chile recorded some of its coldest temperatures in history on June 30, as a polar wave brought subzero conditions from the Altiplano to Patagonia. The extreme cold led to closure of a key border crossing between Chile and Argentina starting on July 1 due to ice and snow accumulations.
Mühlendorf museum destroyed, 100 evacuated after multiple mudslides hit Gschnitztal valley, Tyrol, Austria
Severe thunderstorms triggered at least six mudslides in Gschnitz, Tyrol, Austria at around 18:00 local time (LT) on June 30, 2025, prompting the evacuation of over 100 people and causing extensive infrastructural damage. Follow-up landslides and evacuations continued through July 2, while local and military crews carry out major cleanup operations.
Warragamba Dam risks overflow as bomb cyclone batters New South Wales, Australia
Warragamba Dam in New South Wales (NSW) is neared full capacity on Wednesday, July 2, 2025, and is expected to overflow overnight, as a bomb cyclone delivers intense rain and destructive winds across Australia’s east coast, triggering severe flooding.