The link to the complete text of the change in status doesn’t seem to work on the AVO site, so here it is:
2009-12-28 09:53:11 – VAN/VONA
AVO is raising the Aviation Color Code to YELLOW and the Volcano Alert Level to ADVISORY at Redoubt volcano. At roughly 16:00 AKDT yesterday Dec. 27 (0100 Dec. 28 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.