(1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA)
(2) Issued:	(20161222/0818Z)
(3) Volcano:	Bogoslof (VNUM #311300)
(4) Current Color Code:	ORANGE
(5) Previous Color Code:	RED
(6) Source:	Alaska Volcano Observatory
(7) Notice Number:
(8) Volcano Location:	N 53 deg 55 min W 168 deg 2 min
(9) Area:	Aleutians
(10) Summit Elevation:	492 ft (150 m)
(11) Volcanic Activity Summary:	The explosive eruption that started at about 01:10 UTC 12/22 (16:10 AKST today) was short-lived and produced an ash cloud as high as 35,000 ft asl that drifted northward. Seismic data recorded on neighboring island networks indicates that the eruption lasted about 30 minutes after which seismicity rapidly declined and remains low. No activity has been observed in recent satellite images or infrasound data. On the basis of this information, the Aviation Color Code is lowered to ORANGE and the Alert Level to WATCH. AVO has no ground-based volcano monitoring equipment on Bogoslof volcano. We will monitor satellite images and data from distant seismic and infrasound instruments for indications of significant explosive activity.
(12) Volcanic cloud height:	none detected
(13) Other volcanic cloud information:	Unknown
(14) Remarks:	Status of the ash cloud can be found at the Alaska Aviation Weather Unit website at http://aawu.arh.noaa.gov/
(15) Contacts:	Michelle Coombs, Scientist-in-Charge, USGS mcoombs@usgs.gov (907) 786-7497 Janet Schaefer, Acting Coordinating Scientist, DGGS janet.schaefer@alaska.gov (907) 322-4085
(16) Next Notice:

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AVO/USGS Volcanic Activity Notice

Volcano: Bogoslof (VNUM #311300)

Current Volcano Alert Level: WATCH
Previous Volcano Alert Level: WARNING

Current Aviation Color Code: ORANGE
Previous Aviation Color Code: RED

Issued: Wednesday, December 21, 2016, 11:18 PM AKST
Source: Alaska Volcano Observatory
Notice Number:
Location: N 53 deg 55 min W 168 deg 2 min
Elevation: 492 ft (150 m)
Area: Aleutians

Volcanic Activity Summary: The explosive eruption that started at about 01:10 UTC 12/22 (16:10 AKST today) was short-lived and produced an ash cloud as high as 35,000 ft asl that drifted northward. Seismic data recorded on neighboring island networks indicates that the eruption lasted about 30 minutes after which seismicity rapidly declined and remains low. No activity has been observed in recent satellite images or infrasound data. On the basis of this information, the Aviation Color Code is lowered to ORANGE and the Alert Level to WATCH.

AVO has no ground-based volcano monitoring equipment on Bogoslof volcano. We will monitor satellite images and data from distant seismic and infrasound instruments for indications of significant explosive activity.

Recent Observations:
[Volcanic cloud height] none detected
[Other volcanic cloud information] Unknown

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

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

Janet Schaefer, Acting Coordinating Scientist, DGGS
janet.schaefer@alaska.gov (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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