(1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA)
(2) Issued:(20100405/1859Z)
(3) Volcano:Redoubt (CAVW# 1103-03-)
(4) Current Color Code:YELLOW
(5) Previous Color Code:
(6) Source:Alaska Volcano Observatory
(7) Notice Number:2010/A2
(8) Volcano Location:N 60 deg 29 min W 152 deg 44 min
(9) Area:Cook Inlet-South Central Alaska
(10) Summit Elevation:10197 ft (3108 m)
(11) Volcanic Activity Summary:AVO is raising the Aviation Color Code to YELLOW and the Volcano Alert Level to ADVISORY at Redoubt volcano. This morning, at roughly 01:44 AKDT (0944 UTC) a series of small repetitive earthquakes began occurring in the vicinity of the volcano's summit. Activity is continuing this morning. See http://www.avo.alaska.edu/webicorders/Redoubt/RSO_EHZ_AV.php

These earthquakes may be precursory to renewed eruptive activity at the volcano and increased instability of the lava dome. Whether this will result in explosive activity or failure of the lava dome is unknown at this time. However, there is a heightened possibility of volcanic activity that would produce a volcanic ash cloud, pyroclastic avalanches, and lahars and flooding down the Drift River.

(12) Volcanic cloud height:Unknown
(13) Other volcanic cloud information:Unknown
(14) Remarks:Heavily ice-mantled Redoubt volcano is located on the western side of Cook Inlet, 170 km (106 mi) southwest of Anchorage and 82 km (51 mi) west of Kenai, within Lake Clark National Park. Redoubt is a stratovolcano which rises to 10,197 feet above sea level. Recent eruptions occurred in 1902, 1966-68, 1989-90, and 2009. The 1989-90 and 2009 eruptions produced mudflows, or lahars, that traveled down the Drift River and partially flooded the Drift River Oil Terminal facility. The ash plumes produced by the 1989-90 and 2009 eruptions significantly disrupted air traffic and resulted in minor or trace amounts of ash in the city of Anchorage and other communities in south-central and interior Alaska.
(15) Contacts:Chris Waythomas, Acting Scientist-in-Charge, USGS
cwaythomas@usgs.gov (907) 786-7497

Steve McNutt, Coordinating Scientist, UAF
steve@giseis.alaska.edu (907) 474-7131
(16) Next Notice:A new VONA will be issued if conditions change significantly or alert levels are modified. While a VONA is in effect, regularly scheduled updates are posted at http://www.avo.alaska.edu