Mt. Fitzherbert

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift westward to southwestward.

Potential ash hazards to aviation: Under current eruptive conditions, any ash clouds produced are unlikely to exceed 15,000 feet in altitude. Ashfall from such events rarely reaches more than 20 miles downwind. If the lava dome continues to grow over the next several months, it will become able to produce larger ash clouds that reach higher altitudes and extend farther downwind.

Recent observations: Crews had a productive day in the field yesterday. Two GPS instruments were slung by helicopter onto the thickened and rapidly flowing eastern arm of the crater glacier for a week-long deployment. The perturbation of the glacier caused by ongoing lava-dome growth provides a unique natural laboratory for studying glacier mechanics. Data from the GPS instruments will provide critical flow-velocity measurements. A GPS and seismic station that had ridden on the lava dome for the past 8 days was retrieved, serviced, and redeployed to a spot just near the north end of the new lava dome. Thermal-imaging and observation flights were also conducted. This morning a diffuse ash plume is drifting over the west rim of the crater.