(1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA)
(2) Issued:	(20170416/0320Z)
(3) Volcano:	Bogoslof (VNUM #311300)
(4) Current Color Code:	ORANGE
(5) Previous Color Code:	YELLOW
(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:	An increase in earthquake activity from Bogoslof was detected from stations on nearby islands starting April 15 around 15:01 AKST / 23:01 UTC. At this time there has been no evidence of renewed eruptive activity from infrasound, lightning, or satellite data. Similar sequences of earthquakes have preceded some of the explosive events during the ongoing unrest. Because this uptick in seismicity increases the likelihood of future explosive activity, AVO is raising the Aviation Color Code for Bogoslof to ORANGE and the Volcano Alert Level to WATCH. Bogolsof is not monitored by a real-time seismic network and this inhibits AVO's ability to detect unrest that may lead to an explosive eruption. Rapid detection of an ash-producing eruption may be possible using a combination of data from seismic and infrasound networks on neighboring islands and satellite and lightning detection data.
(12) Volcanic cloud height:	N/A
(13) Other volcanic cloud information:	N/A
(14) Remarks:	Given the lack of a local monitoring network and the unpredictability of the volcano, activity at Bogoslof could ramp up again at any time. Thus a Temporary Flight Restriction (TFR) remains in effect over the volcano for the time being. Please see http://tfr.faa.gov/tfr2/list.html for the status of the TFR.
(15) Contacts:	Dave Schneider, Acting Scientist-in-Charge, USGS djschneider@usgs.gov (907) 786-7497 Jeff Freymueller, Coordinating Scientist, UAFGI jfreymueller@alaska.edu (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: ADVISORY

Current Aviation Color Code: ORANGE
Previous Aviation Color Code: YELLOW

Issued: Saturday, April 15, 2017, 7:20 PM AKDT
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: An increase in earthquake activity from Bogoslof was detected from stations on nearby islands starting April 15 around 15:01 AKST / 23:01 UTC. At this time there has been no evidence of renewed eruptive activity from infrasound, lightning, or satellite data. Similar sequences of earthquakes have preceded some of the explosive events during the ongoing unrest. Because this uptick in seismicity increases the likelihood of future explosive activity, AVO is raising the Aviation Color Code for Bogoslof to ORANGE and the Volcano Alert Level to WATCH.

Bogolsof is not monitored by a real-time seismic network and this inhibits AVO's ability to detect unrest that may lead to an explosive eruption. Rapid detection of an ash-producing eruption may be possible using a combination of data from seismic and infrasound networks on neighboring islands and satellite and lightning detection data.

Recent Observations:
[Volcanic cloud height] N/A
[Other volcanic cloud information] N/A
[Lava flow/dome] N/A
[Lava flow] N/A

Remarks: Given the lack of a local monitoring network and the unpredictability of the volcano, activity at Bogoslof could ramp up again at any time. Thus a Temporary Flight Restriction (TFR) remains in effect over the volcano for the time being. Please see http://tfr.faa.gov/tfr2/list.html for the status of the TFR.

Contacts: Dave Schneider, Acting Scientist-in-Charge, USGS
djschneider@usgs.gov (907) 786-7497

Jeff Freymueller, Coordinating Scientist, UAFGI 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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