(1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA)
(2) Issued:	(20080729/0151Z)
(3) Volcano:	Okmok (VNUM #311290)
(4) Current Color Code:	RED
(5) Previous Color Code:	ORANGE
(6) Source:	Alaska Volcano Observatory
(7) Notice Number:	2008/A17
(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 indicate ash may have reached 35,000 ft in a plume heading E to SE from the volcano. The intensity and duration of seismicity from the eruption at Okmok has changed from continuous tremor to a pulsating signal over the past 7.0 hours. These pulses are strong enough to be easily identified on seismometers on Makushin Volcano on Unalaska Island. 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: WARNING
Previous Volcano Alert Level: WATCH

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

Issued: Monday, July 28, 2008, 5:51 PM AKDT
Source: Alaska Volcano Observatory
Notice Number: 2008/A17
Location: N 53 deg 23 min W 168 deg 9 min
Elevation: 3520 ft (1073 m)
Area: Aleutians

Volcanic Activity Summary: Satellite images indicate ash may have reached 35,000 ft in a plume heading E to SE from the volcano. The intensity and duration of seismicity from the eruption at Okmok has changed from continuous tremor to a pulsating signal over the past 7.0 hours. These pulses are strong enough to be easily identified on seismometers on Makushin Volcano on Unalaska Island.

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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