ALASKA VOLCANO OBSERVATORY STATUS REPORT
U.S. Geological Survey
Monday, December 26, 2016, 7:08 PM AKST (Tuesday, December 27, 2016, 04:08 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

Bogoslof volcano remains in a state of elevated unrest following this afternoon's explosive eruption, the fourth such event since this eruptive sequence began on December 20. Although explosive activity has subsided at present, based on the unpredictability of the situation the status of the volcano remains at Aviation Color Code RED and Alert Status WARNING.

Satellite images showed the plume from today's event rose to about 30,000 ft asl and was carried to the northeast by prevailing winds. Retrospective analysis of seismic, infrasound, and satellite data suggest that following the initial increase in seismicity around 14:05 AKST (23:05 UTC) today, explosive ash emission started at about 14:30 AKST (23:30 UTC) and lasted for approximately one hour. Windy conditions on Umnak Island appear to be obscuring Bogoslof's volcanic signal on seismic instruments there since about 15:20 AKST, limiting our seismic detection capabilities.

AVO has no ground-based volcano monitoring equipment on Bogoslof volcano. We continue to monitor satellite images, data from distant seismic and infrasound instruments, and information from the Worldwide Lightning Location Network for indications of significant activity.

Status of the ash cloud can be found at the Alaska Aviation Weather Unit website at http://aawu.arh.noaa.gov/

OTHER ALASKA VOLCANOES

Other Alaska volcanoes show no signs of significant unrest: http://www.avo.alaska.edu/activity/

AVO scientists conduct daily checks of earthquake activity at all seismically-monitored volcanoes, examine web camera and satellite images for evidence of airborne ash and elevated surface temperatures, and consult other monitoring data as needed.

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

FOR MORE INFORMATION ON ALASKA VOLCANOES: http://www.avo.alaska.edu

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

FOLLOW AVO ON FACEBOOK: https://facebook.com/alaska.avo

FOLLOW AVO ON TWITTER: https://twitter.com/alaska.avo

CONTACT INFORMATION:

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

Pavel Izbekov, Acting Coordinating Scientist, UAFGI
pavel@gi.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.

---