(1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA)
(2) Issued:	(20170218/1439Z)
(3) Volcano:	Bogoslof (VNUM #311300)
(4) Current Color Code:	RED
(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:	An explosive eruption began at Bogoslof volcano at 04:26 AKST (13:26 UTC) as indicated in seismic and lightning data. Preliminary evidence from satellite suggests the cloud is at least as high as 25,000 ft asl. Seismic data suggest that the main ash emissions lasted for several minutes and seismicity is currently low again. AVO is evaluating all data sources and will update this report as more information becomes available.
(12) Volcanic cloud height:	At least 25,000 ft all
(13) Other volcanic cloud information:	winds are variable in the area
(14) Remarks:	The National Weather Service Alaska Aviation Weather Unit has issued an eruption SIGMET warning for aviation up to 25,000 ft above sea level. This may be revised as new information becomes available. Please see the NWS AAWU at http://www.weather.gov/aawu/sigmets for updated information on aviation warning messages.
(15) Contacts:	Michelle Coombs, Scientist-in-Charge, USGS mcoombs@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: WARNING

Current Aviation Color Code: RED

Issued: Saturday, February 18, 2017, 5:39 AM 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: An explosive eruption began at Bogoslof volcano at 04:26 AKST (13:26 UTC) as indicated in seismic and lightning data. Preliminary evidence from satellite suggests the cloud is at least as high as 25,000 ft asl. Seismic data suggest that the main ash emissions lasted for several minutes and seismicity is currently low again.

AVO is evaluating all data sources and will update this report as more information becomes available.

Recent Observations:
[Volcanic cloud height] At least 25,000 ft all
[Other volcanic cloud information] winds are variable in the area

Hazard Analysis:
[Ashfall] No ash fall currently expected on communities.

Remarks: The National Weather Service Alaska Aviation Weather Unit has issued an eruption SIGMET warning for aviation up to 25,000 ft above sea level. This may be revised as new information becomes available. Please see the NWS AAWU at http://www.weather.gov/aawu/sigmets for updated information on aviation warning messages.

Contacts: Michelle Coombs, Scientist-in-Charge, USGS
mcoombs@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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