🌎 Weekly Earth Watch: Volcanoes, Earthquakes & Natural Hazards

Orbis Weather | Sunday, October 4, 2026

Earth remained highly active during the past week, with erupting volcanoes around the Pacific Ring of Fire, a new magma intrusion beneath Hawaiʻi’s Kīlauea, major flooding across parts of Asia, powerful Pacific hurricanes, landslides, and continued seismic activity around the globe.

Here are the major events Orbis Weather is tracking.

🌋 VOLCANO WATCH

🌋 Kīlauea, Hawaiʻi — Magma Intrusion Beneath Summit

Kīlauea remains one of the most closely watched volcanoes on Earth.

During September 24–30, intermittent spattering, lava overflows and incandescence continued within the summit caldera. Some lava fountains at the north vent rose roughly 5–10 meters (16–33 feet) above the growing cone.

Then something particularly interesting happened.

Beginning during the afternoon of September 30, approximately 40 earthquakes were detected beneath Halemaʻumaʻu and the southern caldera as instruments indicated a shallow magma intrusion beneath the summit.

As of October 3, USGS reported that the intrusion had not reactivated, although earthquakes continued beneath Halemaʻumaʻu. Strong glow and flames remained visible at the vents.

Kīlauea remains at:

⚠️ Volcano Alert Level: WATCH
✈️ Aviation Color Code: ORANGE

USGS says another episode of lava fountaining remains possible.

🌋 Anak Krakatau Reshapes Its Island — Indonesia

One of this week’s most fascinating geological developments came from Indonesia.

Recent eruptions at Anak Krakatau have physically changed the volcano’s coastline.

Indonesia’s geological authorities reported that lava deposits from the major September eruption expanded the island by approximately 32.8 hectares (81 acres).

Even more remarkably, satellite imagery revealed two small new land formations near the volcano.

Anak Krakatau sits in the Sunda Strait between Java and Sumatra and is the volcanic successor to the infamous Krakatau volcano whose catastrophic 1883 eruption generated devastating tsunamis.

The latest changes are another reminder that volcanic islands can literally reshape the planet in a matter of days.

🌋 Indonesia Remains a Volcanic Hot Zone

Several Indonesian volcanoes remained active.

Lewotolok

Ash plumes repeatedly rose roughly 400–700 meters (1,300–2,300 feet) above the summit during September 24–30.

An active lava flow on the southeastern flank extended approximately 500 meters (1,640 feet), while incandescent material was observed around the summit and upper slopes.

The volcano remained at Alert Level 2.

Merapi

Activity also continued at dangerous Mount Merapi on Java.

Lava avalanches generated by the active lava dome traveled as far as 2.5 kilometers (1.6 miles) down drainage channels on the volcano’s southwestern and southern flanks.

Merapi remained at Alert Level 3.

🌋 Reventador, Ecuador — Frequent Explosions

Ecuador’s Reventador volcano remained highly active.

Monitoring networks recorded approximately 74–97 explosions per day, while ash-and-gas plumes climbed as high as 1.3 kilometers (0.8 miles) above the crater.

Incandescent volcanic blocks were also observed rolling more than a kilometer down the slopes.

Authorities maintained the volcano at Orange Alert.

🌋 Stromboli, Italy

The “Lighthouse of the Mediterranean” continued its characteristic explosive activity.

Both northern and south-central crater areas produced repeated Strombolian explosions, ejecting lapilli, volcanic bombs and ash above the vents.

Explosion frequency was described as medium to high, although individual explosions were generally low intensity.

Stromboli remained at Yellow Alert.

🌎 EARTHQUAKE WATCH

Global earthquake activity continued along the world’s major tectonic boundaries.

One notable U.S. event occurred near Wauna, Washington, where USGS recorded a magnitude 4.15 earthquake on September 29. The event produced weak shaking and received a Green PAGER alert, indicating a low likelihood of significant casualties or economic losses.

The broader pattern remains familiar: earthquake activity continues to cluster around the Pacific Ring of Fire, including Alaska, the western Americas, Japan, Indonesia, Papua New Guinea and the southwest Pacific.

The previous week’s powerful M6.6 earthquake near New Caledonia also remains an important reminder of the considerable seismic energy regularly released along the southwest Pacific plate boundaries.

🌊 FLOOD & LANDSLIDE WATCH

🇹🇭 Thailand — Major Flood Disaster

Thailand experienced one of the week’s most serious natural disasters.

Torrential rainfall inundated Bangkok and large portions of the country after some areas received nearly a month’s worth of rain within only a few days.

By September 29, Reuters reported that flooding had affected 42 provinces and killed at least 23 people since September 16.

Bangkok recorded around 320 mm (12.6 inches) of rain in three days.

The flooding disrupted roads, businesses and air travel, while thousands of residents required evacuation or emergency assistance. Damage estimates had climbed into the hundreds of millions of dollars.

Additional heavy rainfall remains a concern heading into early October, with forecasters warning about renewed flash flooding, river flooding and mudslides.

🇮🇳 India & 🇳🇵 Nepal — Deadly Flooding

Extreme rainfall also struck parts of India and Nepal.

In India’s Uttar Pradesh, Reuters reported 56 deaths associated with severe rainfall and flooding.

Nepal reported at least 14 deaths with 11 people missing, while rising rivers created additional flash-flood concerns.

Mountainous terrain makes Nepal particularly vulnerable because intense rainfall can rapidly trigger landslides, debris flows and sudden river surges.

🇨🇷 Costa Rica — Hundreds of Homes Flooded

Central America also experienced significant rainfall.

More than 400 homes in Costa Rica were reported flooded after Tropical Wave 47 brought heavy rainfall across the country.

Already saturated soils increased concerns about additional flooding and landslides.

🌀 PACIFIC STORM WATCH

🇲🇽 Hurricane Polo Strikes Mexico

The eastern Pacific remained exceptionally active.

Hurricane Polo made landfall in Baja California Sur late September 28 before crossing the peninsula and making another landfall near Guaymas, Sonora, on September 29.

Earlier in its life, Polo underwent explosive intensification and briefly reached Category 5 strength before weakening considerably ahead of landfall.

Heavy rainfall created risks of flash flooding and mudslides across northern Mexico.

Moisture associated with Polo and other Pacific systems subsequently spread toward the southwestern United States.

🌺 Hurricane Nolo Soaks Hawaiʻi

Hawaiʻi narrowly avoided a direct hurricane strike, but Hurricane Nolo still produced substantial impacts.

Parts of Maui and the Island of Hawaiʻi received more than 12 inches (300 mm) of rain, resulting in flooded roads, fallen trees, landslides and power disruptions.

Nolo became the third hurricane of the season to pass close to Hawaiʻi, highlighting an unusually active central and eastern Pacific season.

By September 28, the northeastern Pacific had already produced 20 named storms and nine hurricanes, compared with an average of 13.5 named storms and 7.4 hurricanes by that point in the season.

🔥 WILDFIRE WATCH

Although floods and tropical cyclones dominated global disaster headlines this week, wildfire danger has not disappeared.

Dry vegetation remains capable of supporting rapidly spreading fires across drought-affected and seasonally dry regions of the western United States, Mediterranean Europe, South America and Australia.

Conditions can change quickly where strong winds overlap with very low humidity and dry fuels, so local evacuation notices and official fire-agency warnings remain the most important sources during an active incident.

⚠️ EARTH WATCH — WHAT WE’RE WATCHING NEXT

Heading into the week of October 5–11, several areas deserve particularly close attention:

🌋 Kīlauea, Hawaiʻi — renewed magma movement or another lava-fountaining episode.

🌋 Indonesia — Anak Krakatau, Merapi, Lewotolok and other active volcanoes remain under close observation.

🌊 Thailand and Southeast Asia — saturated ground means additional heavy rain could quickly produce renewed flash flooding and landslides.

🌀 Pacific tropics — the extraordinarily active 2026 Pacific hurricane season remains capable of generating additional significant storms.

🌎 Pacific Ring of Fire — continuing earthquake and volcanic activity from Alaska through Japan, Indonesia, Papua New Guinea and the southwest Pacific.

🌍 THE BIG PICTURE

This week’s Earth Watch demonstrates how several natural hazard systems can operate simultaneously.

Volcanoes are erupting. Tectonic plates continue to shift. Tropical cyclones are transporting enormous quantities of moisture. Floods and landslides are affecting millions of people.

None of these individual events means global geological activity is suddenly becoming abnormal. Earth is an active planet, and modern satellites, seismic networks and communications simply allow us to observe these processes with extraordinary detail.

For Orbis Weather, the goal is to bring those hazards together in one place — tracking the forces reshaping our planet right now.

🌎 Orbis Weather — Tracking Earth’s Weather & Natural Hazards