(1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA)
(2) Issued:	(20180916/1756Z)
(3) Volcano:	Semisopochnoi (VNUM #311060)
(4) Current Color Code:	YELLOW
(5) Previous Color Code:	UNASSIGNED
(6) Source:	Alaska Volcano Observatory
(7) Notice Number:
(8) Volcano Location:	N 51 deg 55 min E 179 deg 35 min
(9) Area:	Aleutians
(10) Summit Elevation:	2625 ft (800 m)
(11) Volcanic Activity Summary:	An increase in seismicity beginning 16:31 UTC (08:31 AKDT) on has prompted AVO to raise the Aviation Color Code and Volcano Alert Level to YELLOW/ADVISORY. There is no clear indication from satellite imagery or regional infrasound data that Semisopochnoi is erupting at this time. AVO will continue to monitor Semisopochnoi seismic data and evaluate satellite images.
(12) Volcanic cloud height:	Unknown
(13) Other volcanic cloud information:	Unknown
(14) Remarks:
(15) Contacts:	Chris Waythomas, Acting Scientist-in-Charge, USGS cwaythomas@usgs.gov (907) 786-7497 David Fee, Coordinating Scientist, UAFGI dfee1@alaska.edu (907) 322-4085
(16) Next Notice:	A new VAN will be issued if conditions change significantly or alert levels are modified. While a VAN is in effect, regularly scheduled updates are posted at http://www.avo.alaska.edu

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AVO/USGS Volcanic Activity Notice

Volcano: Semisopochnoi (VNUM #311060)

Current Volcano Alert Level: ADVISORY
Previous Volcano Alert Level: UNASSIGNED

Current Aviation Color Code: YELLOW
Previous Aviation Color Code: UNASSIGNED

Issued: Sunday, September 16, 2018, 9:56 AM AKDT
Source: Alaska Volcano Observatory
Notice Number:
Location: N 51 deg 55 min E 179 deg 35 min
Elevation: 2625 ft (800 m)
Area: Aleutians

Volcanic Activity Summary: An increase in seismicity beginning 16:31 UTC (08:31 AKDT) on has prompted AVO to raise the Aviation Color Code and Volcano Alert Level to YELLOW/ADVISORY.

There is no clear indication from satellite imagery or regional infrasound data that Semisopochnoi is erupting at this time. AVO will continue to monitor Semisopochnoi seismic data and evaluate satellite images.

Recent Observations:
[Volcanic cloud height] Unknown
[Other volcanic cloud information] Unknown

Contacts: Chris Waythomas, Acting Scientist-in-Charge, USGS
cwaythomas@usgs.gov (907) 786-7497

David Fee, Coordinating Scientist, UAFGI
dfee1@alaska.edu (907) 322-4085

Next Notice: A new VAN will be issued if conditions change significantly or alert levels are modified. While a VAN is in effect, regularly scheduled updates are posted at
http://www.avo.alaska.edu

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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