(1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA)
(2) Issued:	(20170517/0700Z)
(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 seismic and infrasound activity from Bogoslof was detected from stations on nearby islands starting today, May 16, around 22:32 AKST (May 17 06:32 UTC) and is continuing. We have no satellite observations yet, but the infrasound signal suggests an explosive eruption has likely begun. No lightning has been detected. AVO is raising the Aviation Color Code for Bogoslof to ORANGE and the Volcano Alert Level to WATCH. We will provide more information as it becomes available including any information about a resulting ash cloud. 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:	not available
(13) Other volcanic cloud information:	winds are to the south
(14) Remarks:
(15) Contacts:	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
(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: Tuesday, May 16, 2017, 11:00 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 seismic and infrasound activity from Bogoslof was detected from stations on nearby islands starting today, May 16, around 22:32 AKST (May 17 06:32 UTC) and is continuing. We have no satellite observations yet, but the infrasound signal suggests an explosive eruption has likely begun. No lightning has been detected. AVO is raising the Aviation Color Code for Bogoslof to ORANGE and the Volcano Alert Level to WATCH.

We will provide more information as it becomes available including any information about a resulting ash cloud.

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] not available
[Other volcanic cloud information] winds are to the south
[Lava flow/dome] N/A
[Lava flow] N/A

Contacts: 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.

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