AVO/USGS Volcanic Activity Notice

Volcano: Iliamna (VNUM #313020)

Current Volcano Alert Level: ADVISORY
Previous Volcano Alert Level: NORMAL

Current Aviation Color Code: YELLOW
Previous Aviation Color Code: GREEN

Issued: Monday, June 5, 2023, 4:53 PM AKDT
Source: Alaska Volcano Observatory
Notice Number: 2023/A815
Location: N 60 deg 1 min W 153 deg 5 min
Elevation: 10016 ft (3053 m)
Area: Cook Inlet-South Central

Volcanic Activity Summary:

An increase in seismicity has been observed at Iliamna volcano beginning at about 12:00 pm AKDT June 5, 2023 (20:00 UTC). The rate of earthquakes initially occurred in 1 minute intervals and have been becoming more closely spaced. There is a possibility that the earthquakes may be related to magmatic movement or hydrothermal fluids beneath the volcano. However, similar activity has been observed before large mass movements or avalanches at Iliamna volcano, and AVO cannot rule out either possibility at this time.

Due to the seismicity at Iliamna being above background levels the Aviation Color Code and Volcano Alert level for Iliamna are being raised to YELLOW and ADVISORY.

Recent Observations:
[Volcanic cloud height] NA
[Other volcanic cloud information] Unknown


Iliamna volcano is located on the western side of lower Cook Inlet in the Lake Clark National Park. Iliamna is a snow-covered stratovolcano which rises 10,020 feet above sea level. Although steam plumes occur on its eastern flanks, there has been no historic volcanic activity at Iliamna. Iliamna is located 225 km (140 miles) southwest of Anchorage and 113 km (70 miles) southwest of Homer.


Aaron Wech, Acting Scientist-in-Charge, USGS (907) 786-7497

David Fee, Coordinating Scientist, UAFGI (907) 378-5460

Next Notice:

A new VAN will be issued if conditions change significantly or alert levels are modified. While a VAN is in effect, regularly scheduled updates are posted at

The Alaska Volcano Observatory is a cooperative program of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute, and the Alaska Division of Geological and Geophysical Surveys.

Hazard Notification System (HANS) for Volcanoes at