ALASKA VOLCANO OBSERVATORY DAILY UPDATE
U.S. Geological Survey
Saturday, August 3, 2019, 11:42 AM AKDT (Saturday, August 3, 2019, 19:42 UTC)

SHISHALDIN VOLCANO (VNUM #311360)
54°45'19" N 163°58'16" W, Summit Elevation 9373 ft (2857 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE

Weak seismic tremor continues. Clouds have obscured the volcano for most of the past 24 hours, but occasional satellite views show elevated surface temperatures from the summit.

Shishaldin is monitored by local seismic and infrasound sensors, satellite data, a web camera, a telemetered geodetic network, and distant infrasound and lightning networks.

SEMISOPOCHNOI VOLCANO (VNUM #311060)
51°55'44" N 179°35'52" E, Summit Elevation 2625 ft (800 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE

Seismicity remains elevated with occasional discrete low-frequency earthquakes. No activity was observed in cloudy satellite images. It remains possible that activity could increase rapidly and with little warning.

Semisopochnoi is monitored with an on-island seismic network and remotely by satellite and lightning sensors. Furthermore, an infrasound array on Adak Island may detect explosive emissions from Semisopochnoi with a 13 minute delay if atmospheric conditions permit.

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

Seismic unrest continues with occasional low-frequency earthquakes. Elevated surface temperatures were observed in partly cloudy satellite data.

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.

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 was observed in cloudy satellite images over the last 24 hours. No activity was detected in regional seismic or infrasound data.

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.

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

David Fee, Coordinating Scientist, UAFGI
dfee1@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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