ALASKA VOLCANO OBSERVATORY DAILY UPDATE
U.S. Geological Survey
Monday, February 25, 2019, 2:32 PM AKST (Monday, February 25, 2019, 23:32 UTC)

CLEVELAND VOLCANO (VNUM #311240)
52°49'20" N 169°56'42" W, Summit Elevation 5676 ft (1730 m)
Current Volcano Alert Level: ADVISORY
Current Aviation Color Code: YELLOW

No activity observed or detected today in mostly cloudy satellite images and regional geophysical data. The Aviation Color Code was reduced to YELLOW and the Volcano Alert Level to ADVISORY earlier today. Satellite data from late last week show that the lava dome that was erupted in the summit crater in mid-January 2019 has continued to subside, indicative that eruptive activity had ceased. There has been no explosive activity detected in regional seismic or infrasound data since early January 2019.

Cleveland remains restless. Additional episodes of lava effusion and explosions are likely and will occur without advance warning. Explosions from Cleveland are normally short duration and only present a hazard to aviation in the immediate vicinity of the volcano. Larger explosions that present a more widespread hazard to aviation are possible, but are less likely and occur less frequently.

Local seismic and infrasound data at Cleveland have been unavailable since January 26, 2019. This restricts AVO's ability to rapidly detect an explosive eruption. AVO is able to monitor the volcano for signs of eruptive activity with satellite, lightning, and regional seismic and infrasound data.

VENIAMINOF VOLCANO (VNUM #312070)
56°11'52" N 159°23'35" W, Summit Elevation 8225 ft (2507 m)
Current Volcano Alert Level: ADVISORY
Current Aviation Color Code: YELLOW

No activity observed in mostly cloudy satellite and web camera images over the past day. The level of seismicity remains low.

It remains possible for eruptive activity consisting of lava effusion, ash emissions or both to resume at any time without significant precursory seismic events.

Veniaminof volcano is monitored with a local real-time seismic network, which will typically allow AVO to detect changes in unrest that may lead to a more significant explosive eruption. AVO combines seismic, infrasound, lightning, and satellite data for rapid detection of such events.

GREAT SITKIN VOLCANO (VNUM #311120)
52°4'35" N 176°6'39" W, Summit Elevation 5709 ft (1740 m)
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN

The Aviation Color Code reduced to GREEN and the Volcano Alert Level to NORMAL earlier today. Seismic activity has been at very low levels for the past several weeks and is now within the range of normal background variability. No signs of activity observed in satellite data or detected on regional geophysical networks.

Great Sitkin volcano is monitored with a local real-time seismic network, which will typically allow AVO to detect changes in unrest that may lead to an explosive eruption. Rapid detection of an ash-producing eruption would be accomplished using a combination of seismic, infrasound, lightning, and satellite data.

OTHER ALASKA VOLCANOES

Information on all Alaska volcanoes is available at : http://www.avo.alaska.edu.

For definitions of Aviation Color Codes and Volcano Alert Levels, see: http://www.avo.alaska.edu/color_codes.php

SUBSCRIBE TO VOLCANO ALERT MESSAGES by email: http://volcanoes.usgs.gov/vns/

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CONTACT INFORMATION:

Michelle Coombs, Scientist-in-Charge, USGS
mcoombs@usgs.gov (907) 786-7497

Pavel Izbekov, Acting Coordinating Scientist, UAFGI
peizbekov@alaska.edu (907) 322-4085

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.

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