(1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA)
(2) Issued:	(20171213/1515Z)
(3) Volcano:	Cleveland (VNUM #311240)
(4) Current Color Code:	ORANGE
(5) Previous Color Code:	YELLOW
(6) Source:	Alaska Volcano Observatory
(7) Notice Number:
(8) Volcano Location:	N 52 deg 49 min W 169 deg 56 min
(9) Area:	Aleutians
(10) Summit Elevation:	5676 ft (1730 m)
(11) Volcanic Activity Summary:	An explosion was detected at Cleveland Volcano in seismic and infrasound data this morning 04:20 AKST (13:20 UTC). The explosion produced an eruption cloud that was observed in satellite data to an altitude of up to 20,000 ft asl and moving to the east. AVO is raising the color code for Cleveland to Aviation Color Code ORANGE and Alert Level WATCH.
(12) Volcanic cloud height:	Small cloud detected. NWS eruption SIGMET issued to 20,000 ft asl.
(13) Other volcanic cloud information:	Cloud moving to the east.
(14) Remarks:	The National Weather Service Alaska Aviation Weather Unit has issued an eruption SIGMET warning for aviation up to 20,000 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. Cleveland volcano is not monitored with a full real-time seismic network and this inhibits AVO's ability to detect unrest that may lead to future activity. We are able to detect explosive activity using infrasound and limited seismic instruments on the island.
(15) Contacts:	Michelle Coombs, Scientist-in-Charge, USGS mcoombs@usgs.gov (907) 786-7497 Jessica Larsen, Acting Coordinating Scientist, UAF jflarsen@alaska.edu (907) 322-4085
(16) Next Notice:

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AVO/USGS Volcanic Activity Notice

Volcano: Cleveland (VNUM #311240)

Current Volcano Alert Level: WATCH
Previous Volcano Alert Level: ADVISORY

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

Issued: Wednesday, December 13, 2017, 6:15 AM AKST
Source: Alaska Volcano Observatory
Notice Number:
Location: N 52 deg 49 min W 169 deg 56 min
Elevation: 5676 ft (1730 m)
Area: Aleutians

Volcanic Activity Summary: An explosion was detected at Cleveland Volcano in seismic and infrasound data this morning 04:20 AKST (13:20 UTC). The explosion produced an eruption cloud that was observed in satellite data to an altitude of up to 20,000 ft asl and moving to the east. AVO is raising the color code for Cleveland to Aviation Color Code ORANGE and Alert Level WATCH.

Recent Observations:
[Volcanic cloud height] Small cloud detected. NWS eruption SIGMET issued to 20,000 ft asl.
[Other volcanic cloud information] Cloud moving to the east.

Remarks: The National Weather Service Alaska Aviation Weather Unit has issued an eruption SIGMET warning for aviation up to 20,000 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.

Cleveland volcano is not monitored with a full real-time seismic network and this inhibits AVO's ability to detect unrest that may lead to future activity. We are able to detect explosive activity using infrasound and limited seismic instruments on the island.

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

Jessica Larsen, Acting Coordinating Scientist, UAF
jflarsen@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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