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December 1, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift northward to northeastward in the morning, and northeastward later in the day.
- Potential ash hazards to aviation: Under current eruptive conditions, small, short-lived explosions may produce ash clouds that exceed 30,000 feet in altitude. Ash from such events can travel 100 miles or more downwind.
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- Recent observations: There have been no significant changes in the pattern of activity during the past 24 hours. Yesterday a field crew made minor repairs to data acquisition and telemetry equipment at Coldwater Visitor Center. Stormy weather will likely preclude field operations for the remainder of this week.
- *** This line included in daily update but excluded for rest of month on this page.
December 2, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift east-northeastward.
- Recent observations: There have been no significant changes in the pattern of activity during the past 24 hours. Stormy weather continues to preclude field operations at the volcano.
December 3, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift southeastward.
- Recent observations: There have been no significant changes in the pattern of activity during the past 24 hours. Stormy weather continues to preclude field operations at the volcano.
December 4, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift to the southeast.
- Recent observations: There have been no significant changes in the pattern of activity during the past 24 hours. Stormy weather continues to preclude visual observations and field operations at the volcano.
December 5, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift southeastward.
- Recent observations: In a by now well-established pattern, tiny “drumbeat” earthquakes continue at a rate of one every one to two minutes and other monitoring data remain in typical ranges. Hopefully slightly improved weather conditions over the next few days will allow some visual observation of the volcano.
December 6, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- 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 southeastward, although low level winds later in the day could also carry ash in a northwestward direction.
- Recent observations: Clear conditions reveal the volcano emitting a moderate vapor plume this morning. The well-established pattern of tiny “drumbeat” earthquakes continues at a rate of one every one to two minutes and other monitoring data remain in typical ranges. Despite the continuing procession of earthquakes, the overall seismic energy release is very low compared to that of early phases of the eruption. Improving weather conditions over the next few days hopefully will allow some visual observations of the volcano.
December 7, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift northwestward at low altitudes and east-southeastward at higher altitudes early in the day changing to northwestward to northward later.
- Recent observations: Aerial observations yesterday revealed the source of the thin ash deposit that coats the crater’s south wall and, as seen from the Portland metropolitan area, extends down the outer south flank as a faint brownish-gray streak. Hot rock fall from the south side of the actively growing part of the new lava dome was the culprit. Fresh rock debris lies at the base of the dome and thick ash lies on adjacent newly fallen snow on the fractured glacier. Although no precise measurements are available, the active part of the dome is noticeably higher and broader than when last seen two weeks ago.
December 8, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift westward at low altitudes and west-southwestward to southwestward at higher altitudes.
- Recent observations: Field crews are taking advantage of today’s clear weather to work on telemetry linkages and to make visual observations. The active part of the lava dome has become visually bigger, but as yet we cannot quantify the change. At 10:40pm Wednesday a relatively large earthquake punctuated the on-going procession of small “drumbeat” earthquakes. Otherwise, patterns of seismicity and deformation remain unchanged.
December 9, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift westward at low altitudes and southwestward at higher altitudes.
- Recent observations: One of the sporadic, larger (magnitude 2.8) earthquakes that characterize the ongoing eruption occurred shortly before 9 a.m. today and evidently generated some rock fall. The rock fall sent up a small diffuse ash plume that was faintly visible from the Portland metropolitan area. Photographs of the growing lava dome from yesterday’s observation flight should be on our web site later today. All monitoring data remain within typical ranges of seismicity and ground deformation.
December 10, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift westward to west-northwestward at low elevations and broadly northwestward to southeastward at higher elevations.
- Recent observations: Clear conditions at the volcano this morning provide optimal viewing conditions. Lava continues to extrude and grow the dome. A rockfall off the dome at 6:32 this morning sent a small ash plume above rim level, which then rapidly dissipated. Further rockfalls could generate similar plumes later today, which may be visible from the metropolitan area. Seismicity continues its ongoing procession of tiny “drumbeat” earthquakes about every one to two minutes. Overall, the rate of seismic energy release remains relatively low, and other monitoring data are within the range of their typical recent values.
December 11, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift northward to north-northeastward early in the day and north-northeastward later.
- Recent observations: Small rock falls continue from the growing lava dome. Larger ones may produce ash plumes that are visible above the crater rim. Patterns of earthquakes and ground deformation remain unchanged from recent trends.
December 12, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- 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 early today would drift broadly west to northeast at low levels, northeast at high levels and east to southeast later in the day.
- Recent observations: Small rock falls continue from the growing lava dome. Larger ones may produce ash plumes that are visible above the crater rim. Patterns of earthquakes and ground deformation remain unchanged from recent trends.
December 13, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that any ash clouds that rise above the crater rim early today would drift south-southeastward.
- Recent observations: Small rock falls continue from the growing lava dome. Larger ones may produce ash plumes that are visible above the crater rim. Patterns of earthquakes and ground deformation remain unchanged from recent trends. The volume of the dome measured on October 24, 2005, was 70 million cubic meters—about 90% of the volume of the 1980-to-1986 dome.
December 14, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that ash clouds that rise up to about 15,000 feet above the crater rim (about 23,000 feet above sea level) today would drift southwestward to northwestward; higher-altitude ash clouds would drift east-southeastward.
- Recent observations: Small rock falls continue from the growing lava dome. Larger ones may produce ash plumes that are visible above the crater rim. Patterns of earthquakes and ground deformation remain unchanged from recent trends. The volume of the dome measured on October 24, 2005, was 70 million cubic meters—about 90% of the volume of the 1980-to-1986 dome.
December 15, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that ash clouds that rise up to about 15,000 feet above the crater rim (about 23,000 feet above sea level) today would drift northwestward, but higher-altitude ash clouds would drift southeastward.
- Recent observations: Small rock falls continue from the growing lava dome. Larger ones may produce ash plumes that are visible above the crater rim. Patterns of earthquakes and ground deformation remain unchanged from recent trends. Repeat images from fixed cameras within the crater and at the crater rim show that the seventh lava spine continues to push upward and southwestward from a source just south of the 1980-to-1986 dome.
December 16, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that ash clouds that rise up to about 15,000 feet above the crater rim (about 23,000 feet above sea level) today would drift westward to southward, but higher-altitude ash clouds would drift southwestward, shifting by late afternoon, south-southeastward.
- Recent observations: Small rock falls continue from the growing lava dome. Larger ones may produce ash plumes that are visible above the crater rim. Patterns of earthquakes and ground deformation remain unchanged from recent trends. Field parties yesterday dredged rock samples from the actively growing spine, repaired the telemetry system, and retrieved a damaged seismic station from the old dome, which had tipped over owing to ice accumulation on its antenna.
December 17, 2005:
December 18, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that ash clouds that rise up to about 15,000 feet above the crater rim (about 23,000 feet above sea level) today would drift to the northwest. Higher-altitude ash clouds would also drift to the northwest early in the day, shifting to the north to northeast later in the day.
- Recent observations: Small rock falls continue from the growing lava dome. Larger ones may produce ash plumes that are visible above the crater rim. Patterns of earthquakes and ground deformation remain unchanged from recent trends.
December 19, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that ash clouds that rise above the crater rim today would drift northeastward to east-northeastward.
- Recent observations: Small rock falls continue from the growing lava dome. Larger ones may produce ash plumes that are visible above the crater rim. Patterns of earthquakes and ground deformation remain unchanged from recent trends. Weather conditions this week will likely prevent any field work.
December 20, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that ash clouds that rise above the crater rim today would drift northeastward to east-northeastward.
- Recent observations: Small rock falls continue from the growing lava dome. Larger ones may produce ash plumes that are visible above the crater rim. Patterns of earthquakes and ground deformation remain unchanged from recent trends. Weather conditions this week will likely prevent any field work.
December 21, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that ash clouds that rise above the crater rim today would drift northeastward to east-northeastward.
- Recent observations: Small rock falls continue from the growing lava dome. Larger ones may produce ash plumes that are visible above the crater rim. Patterns of earthquakes and ground deformation remain unchanged from recent trends. Weather conditions this week will likely prevent any field work and has prevented visual observations since December 18.
December 22, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that ash clouds that rise above the crater rim today would drift northeastward.
- Recent observations: Small rock falls continue from the growing lava dome. Larger ones may produce ash plumes that are visible above the crater rim. Patterns of earthquakes and ground deformation remain unchanged from recent trends. A small to moderate seismic event was recorded on crater stations at 05:57 this morning. Weather conditions this week will likely prevent any field work.
December 23, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that ash clouds that rise above the crater rim today would drift eastward to northeastward.
- Recent observations: Small rock falls continue from the growing lava dome. Larger ones may produce ash plumes that are visible above the crater rim. Patterns of earthquakes and ground deformation remain unchanged from recent trends. Poor weather conditions this week have prevented any field work. There have been no visual observations of the new dome growth since December 18.
December 24, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that ash clouds that rise above the crater rim today would drift to the northeast.
- Recent observations: Small rock falls continue from the growing lava dome. Larger ones may produce ash plumes that are visible above the crater rim. Patterns of earthquakes and ground deformation remain unchanged from recent trends. There have been no visual observations of the new dome growth since December 18.
December 25, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that ash clouds that rise above the crater rim today would drift to the northeast.
- Recent observations: Small rock falls continue from the growing lava dome. Larger ones may produce ash plumes that are visible above the crater rim. Patterns of earthquakes and ground deformation remain unchanged from recent trends. A small increase in RSAM levels occurred over night, but the increase is waning to levels consistent with levels recorded over the last week. There have been no visual observations of the new dome growth since December 18.
December 26, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that ash clouds that rise above the crater rim today would drift to the northeast.
- Recent observations: Patterns of earthquakes and ground deformation remain unchanged from recent trends. Yesterday evening, a magnitude 2.8 earthquake, one of the larger of typical events, occurred at shallow depth beneath the dome at 7:47:52 p.m. No visual observations of the new dome have been made since December 18 owing to inclement weather. We suspect that a reported red bag of gifts within the crater is really nothing more than hot rock glowing incandescently from cracks as the lava dome continues its inexorable growth.
December 27, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that ash clouds that rise above the crater rim today would drift to the northeast.
- Recent observations: The eruption continues by the slow extrusion of dacite lava within the crater of Mount St. Helens. Seismicity is marked by the repetitive small earthquakes, occuring every 2-3 minutes, that have come to characterize the past 15 months. Tiltmeters within 500 m of the new lava dome show minute ground deformation; whereas the volcano’s flanks are quiet. Currently, however, we’re missing two of our standard monitoring tools. A problem with satellite communications has interrupted the data from GPS receivers situated within the crater; and welcomed winter storms have kept us from visual observations of the volcano since December 18.
December 28, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that ash clouds that rise above the crater rim today would drift to the northeast.
- Recent observations: Patterns of earthquakes and ground deformation remain unchanged from recent trends. There have been no visual observations of the new dome growth since December 18. Inclement weather conditions this week will likely prevent any field work.
December 29, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that ash clouds that rise above the crater rim today would drift to the east early today and to the northeast later in the day.
- Recent observations: Overnight, there has been no significant change in the level of seismic activity. Patterns of earthquakes and ground deformation remain unchanged from recent trends. There have been no visual observations of the new dome growth since December 18. Inclement weather conditions this week will likely prevent any field work.
December 30, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that ash clouds that rise above the crater rim today would drift to the northeast.
- Recent observations: Overnight, there has been no significant change in the level of seismic activity. Earthquake and ground deformation patterns remain blisteringly unchanged from recent trends. There have been no visual observations of the new dome growth since December 18. Continuing inclement winter weather conditions this week will likely prevent any field work.
December 31, 2005:
- Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE:
- Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash.
- Wind forecasts show that ash clouds that rise above the crater rim today would drift to the northeast.
- Recent observations: The eruption continues by the slow extrusion of dacite lava within the crater of Mount St. Helens. Repetitive small earthquakes occur every 2-3 minutes in the shallow part of the vent. The seismicity remains the best instrumental indication that the eruption is ongoing, because robust winter storms have kept us from visual observations of the volcano since December 18. Two tiltmeters within 500 m of the vent show small ground deformation characteristic of the extrusive process. We wish each of you a Happy New Year, one that likely will be marked by the continued growth of the Mount St. Helens dome during the days and weeks ahead.
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