8 US Volcanoes Under Monitoring by USGS as Elevated Alert Levels Hint Possible Eruption

Of the more than 160 volcanoes the USGS continues to monitor across the US, eight are showing signs of heightened activity that could trigger an eruption.

Shishaldin Volcano, Alaska: WATCH/ORANGE

As intermittent tremors along with low-frequency earthquakes over the last week have evolved into more regular and persistent in the previous day, satellite data over the last 24 hours has detected strongly raised surface temperatures near the peak of Shishaldin Volcano.

AVO warns that while these observations deviate from Shishaldin's usual background activity, they do not necessarily portend the impending eruption.

These findings imply that the Shishaldin top crater most likely contains lava. In response, the Alaska Volcano Observatory AVO increased the Alert Level to WATCH and the Aviation Color Code to ORANGE.

Shishaldin Volcano, a sizable stratovolcano, is situated on Unimak Island in the series of Aleutian Islands in Alaska. With a height of 6,500 feet, it is the highest mountain peak in the Aleutians.

Great Sitkin Volcano, Alaska: WATCH/ORANGE

Sitting in the central Aleutian Islands, the Great Sitkin Volcano is a basaltic andesite volcano that takes up the majority of Great Sitkin Island's northern half. AVO reports that the volcano is still erupting lava slowly, creating a substantial lava flow inside its summit crater.

Since July 2021, the Great Sitkin Volcano has been steadily releasing lava without any occurrences of explosive events.

wAVO has a volcano Alert Level of WATCH because of the ongoing eruption, and the aviation color code is currently ORANGE.

Semisopochnoi, Alaska: ADVISORY/YELLOW

With its location barely 9.7 miles to the west of the 180th Meridian in Alaska, Semisopochnoi occupies the easternmost land location in both the United States and North America.

The AVO reports that Semisopochnoi experienced little seismic activity the previous day. Employed geophysical or remote sensing data showed no signs of explosive activity. Over the past 24 hours, little action was seen in the partly cloudy satellite along with web camera pictures. The USGS does note that tiny explosions and related ash emissions may persist and be challenging to detect, particularly when the volcano is hidden by a layer of dense cloud cover.

The volcano is on ADVISORY and YELLOW, according to the latest AVO update.

Mount Takawangha and Tanaga, Alaska: ADVISORY/YELLOW

An Alaskan stratovolcano named Mount Takawangha, along with the nearby volcano Mount Tanaga, is situated on Tanaga Island. The most recent update report from AVO stated that seismicity had been minimal at Tanaga Island throughout the previous day. Cloudy satellite photos along with web camera images showed little activity. Takawangha is now at an ADVISORY volcano alert level and a YELLOW aviation color code level.

Trident Volcano, Alaska: ADVISORY/YELLOW

On the Alaska Peninsula, inside Katmai National Park, is the Trident Volcano. In a report on Trident published today, AVO noted that the seismic activity in the area of the volcano has been high over the last day.

Satellite and web camera footage taken during the previous day's partly overcast weather did not reveal any movement. On August 24, 2022, the seismic upheaval started and continued until the present. Trident, according to AVO, is also on an ADVISORY volcano alert level and an aviation color code level of YELLOW.

Aniakchak Volcano: ADVISORY/YELLOW

The National Park Service is responsible for maintaining the Aniakchak National Monument and Preserve, which includes the Aniakchak Volcano. AVO reported that Aniakchak volcano experienced modest seismicity throughout the previous day in their most recent volcano update.

Cloudy satellite photos along with web camera pictures from the most recent day revealed little activity. If a future eruption were to take place, it is anticipated that it would be preceded by increased shallow seismicity, other signals of disturbance, such as gas releases, elevated temperatures at the surface, and additional surface deformation.

Kilauea Volcano, Hawaii: ADVISORY/YELLOW

The Kilauea volcano on Hawaii's Big Island is not erupting, and since the last eruption ceased on June 19, 2023, no active lava has been seen. Over the previous week, no notable changes have been seen at the highest point or in either rift zone. While tilt deformation has been steady and seismicity has been at background levels during the previous week, the volcano has continued to release some volcanic gasses, although just in small amounts.

According to USGS, the volcano's current Volcano Alert Level is ADVISORY, and its current Aviation Color Code is YELLOW.

Visitors to Hawaii Volcano National Park or the Kilauea Volcano are urged to proceed with extreme caution at all times by both HVO and USGS, Weatherboy reports.