ALASKA VOLCANO OBSERVATORY DAILY UPDATE
U.S. Geological Survey
Tuesday, June 27, 2017, 12:55 PM AKDT (Tuesday, June 27, 2017, 20:55 UTC)

BOGOSLOF VOLCANO (VNUM #311300)
53°55'38" N 168°2'4" W, Summit Elevation 492 ft (150 m)
Current Volcano Alert Level: WARNING
Current Aviation Color Code: RED

Two explosive eruptions have occurred at Bogoslof volcano in the past 24 hours. The first occurred at 00:45 UTC on June 27 (16:45 AKDT on June 26), and the second occurred at 11:17 UTC, June 27 (03:17 AKDT). Both events were relatively short-duration, lasting only ~14 minutes each based on seismic data, and the two explosions produced volcanic clouds reaching altitudes of 25,000 and 30,000 ft asl, respectively, based on satellite data. The occurrence of a second significant explosion together with its higher altitude cloud, which also produced lightning detected by the World Wide Lightning Location Network (WWLLN), prompted AVO to raise the Aviation Color Code to RED and Volcano Alert Level to WARNING.

Seismicity is currently at background levels, but Bogoslof volcano remains at a heightened state of unrest and in an unpredictable condition. Recent eruptive episodes, including today’s, have produced multiple short-duration explosions with pauses of minutes to hours. Additional explosions producing high-altitude volcanic clouds could occur at any time. The Aviation Color Code remains RED and Volcano Alert Level WARNING. AVO will continue to monitor seismic and infrasound data from nearby islands, as well as lightning data from the World Wide Lightning Location Network for signs of renewed activity.

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

Nothing noteworthy was observed in cloudy satellite or web camera images today, and no unusual activity has been detected in seismic or infrasound data over the past 24 hours.

Cleveland volcano is monitored with a limited real-time seismic network, which inhibits AVO's ability to detect precursory unrest that may lead to an explosive eruption. Rapid detection of an ash-producing eruption may be possible using a combination of seismic, infrasound, lightning, and satellite data.

PAVLOF VOLCANO (VNUM #312030)
55°25'2" N 161°53'37" W, Summit Elevation 8261 ft (2518 m)
Current Volcano Alert Level: ADVISORY
Current Aviation Color Code: YELLOW

Nothing noteworthy was observed in partly cloudy satellite or web camera images today, and no unusual activity has been detected in seismic or infrasound data over the past 24 hours.

The level of unrest at Pavlof can change quickly and the progression to eruptive activity can occur with little or no warning. We continue to monitor Pavlof closely and will provide any new information about the status of the volcano when or if it becomes available.

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

Jeff Freymueller, Coordinating Scientist, UAF
jfreymueller@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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