(1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA)
(2) Issued:	(20080730/1934Z)
(3) Volcano:	Okmok (VNUM #311290)
(4) Current Color Code:	ORANGE
(5) Previous Color Code:	RED
(6) Source:	Alaska Volcano Observatory
(7) Notice Number:	2008/A18
(8) Volcano Location:	N 53 deg 23 min W 168 deg 9 min
(9) Area:	Aleutians
(10) Summit Elevation:	3520 ft (1073 m)
(11) Volcanic Activity Summary:	Satellite images and recent pilot reports indicate the ash plume at Okmok has decreased to altitudes between 15,000 and 20,000 ft and is moving west from the volcano. Seismicity continues to alternate between periods of continuous and pulsating tremor. The pulses continue to be identified on seismometers on Makushin Volcano on Unalaska Island. Based on these observations AVO is lowering the aviation color code at Okmok volcano to ORANGE and the Alert Code to WATCH. Stronger explosive activity could resume at any time with little or no warning.
(12) Volcanic cloud height:
(13) Other volcanic cloud information:
(14) Remarks:	Please see http://www.avo.alaska.edu/activity/Okmok.php for more information.
(15) Contacts:	John Power, Acting Scientist-in-Charge, USGS jpower@usgs.gov, (907)786-7497 Steve McNutt, Coordinating Scientist, UAFGI steve@giseis.alaska.edu (907)978-5458
(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: Okmok (VNUM #311290)

Current Volcano Alert Level: WATCH
Previous Volcano Alert Level: WARNING

Current Aviation Color Code: ORANGE
Previous Aviation Color Code: RED

Issued: Wednesday, July 30, 2008, 11:34 AM AKDT
Source: Alaska Volcano Observatory
Notice Number: 2008/A18
Location: N 53 deg 23 min W 168 deg 9 min
Elevation: 3520 ft (1073 m)
Area: Aleutians

Volcanic Activity Summary: Satellite images and recent pilot reports indicate the ash plume at Okmok has decreased to altitudes between 15,000 and 20,000 ft and is moving west from the volcano. Seismicity continues to alternate between periods of continuous and pulsating tremor. The pulses continue to be identified on seismometers on Makushin Volcano on Unalaska Island. Based on these observations AVO is lowering the aviation color code at Okmok volcano to ORANGE and the Alert Code to WATCH.

Stronger explosive activity could resume at any time with little or no warning.


Remarks: Please see http://www.avo.alaska.edu/activity/Okmok.php for more information.

Contacts: John Power, Acting Scientist-in-Charge, USGS
jpower@usgs.gov, (907)786-7497

Steve McNutt, Coordinating Scientist, UAFGI
steve@giseis.alaska.edu (907)978-5458

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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