|
|
September 1, 2006:
- 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. During such eruptions, changes in the level of activity can occur over days to months. The eruption could intensify suddenly or with little warning and produce explosions that cause hazardous conditions within several miles of the crater and farther downwind. Small lahars could suddenly descend the Toutle River if triggered by heavy rain or by interaction of hot rocks with snow and ice. These lahars pose a negligible hazard below the Sediment Retention Structure (SRS) but could pose a hazard along the river channel upstream.
- Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds rising above the crater rim today would drift westeastward in the morning and northwestward in the evening.
- 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.
***
- Recent observations: Lava dome extrusion continues at Mount St. Helens. No significant changes in seismicity, deformation, or rockfall activity have been detected in the past 24 hours. Hot, dry conditions and strong low-level east winds will result in dust and ash from the growing dome and crater walls being resuspended and blown to the west today. This phenomenon is not unusual for late summer.
- *** This line included in daily update but excluded for rest of month on this page.
September 2, 2006:
- 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 rising above the crater rim today would drift northwest.
- Recent observations: Crews were in the field on Friday to service instruments, but strong winds and dust made helicopter operations difficult.
September 3, 2006:
- 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 rising above the crater rim today would drift northward.
- Recent observations: Conditions are hazy at the volcano today, likely due to numerous forest fires around the state and continued hot, dry, windy conditions. A moderate-sized event associated with a rockfall occurred at about 1 a.m. PDT. Monitoring data show no significant changes at the volcano in the past 24 hours.
September 4, 2006:
- 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 rising above the crater rim today would drift north to northeastward.
- Recent observations: Conditions continue to be hazy at the volcano, likely due to numerous forest fires around the state and continued hot, dry, windy conditions. Monitoring data show no significant changes at the volcano in the past 24 hours.
September 5, 2006:
- 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 rising above the crater rim today would drift east to northeast.
- Recent observations: The volcano is visible today, although conditions are rather hazy owing to dust and smoke from forest fires in the Pacific Northwest.
September 6, 2006:
- 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 rising above the crater rim today would drift predominantly to the south.
- Recent observations: It is sunny at the volcano today. The eruption continues. A M3.2 earthquake occurred at 6:52 am this morning. Such events are expected to occur every few days. Monitoring data show no significant changes at the volcano in the past 24 hours.
September 7, 2006:
- 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 rising above the crater rim today would drift predominantly to the south.
- Recent observations: It is sunny again at the volcano today. Monitoring instruments indicate the eruption continues unabated, accompanied by small earthquakes and occasional larger events with magnitude around M3. Monitoring data show no significant changes at the volcano in the past 24 hours.
September 8, 2006:
- 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 rising above the crater rim today would drift to the north-northeast.
- Recent observations: It is mostly sunny at the volcano today. Monitoring instruments indicate the eruption continues accompanied by small earthquakes and occasional larger events with magnitude around M3. Monitoring data show no significant changes at the volcano in the past 24 hours.
September 9, 2006:
- 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 rising above the crater rim today would drift west to west-southwest
- Recent Observations: The clear early morning skies at Mount St. Helens have given way to cloud-covered conditions, which are expected to persist throughout the day. There have been no significant changes in eruption conditions over the last 24 hours. Two notable shallow earthquakes occurred yesterday amidst the regular drumbeat of low-level seismicity associated with continued dome extrusion (M-2.4 at 10:18hrs PST, M-1.8 at 18:43hrs PST). Such events are routinely associated with this eruption. -- [note of 09-11-06, should read 10:18hrs PDT and 18:43hrs PDT]
September 10, 2006:
- 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 rising above the crater rim today would drift West this morning and shift to North-West later in the day.
- Recent Observations: As reflected by ongoing low-level seismicity, the eruption of Mount St. Helens continues on this clear, sparkling Sunday morning. There have been five greater-than-Magnitude-2 shallow earthquakes in association with continued dome extrusion over the last 24 hours. (Today: M-2.1, 07:12PDT; M2.3, 02:24PDT; M-3.0,02:22PDT; Yesterday: M-2.2, 17:20PDT; M-3.1 12:03PDT).
September 11, 2006:
- 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 rising above the crater rim today would drift northeastward today.
- Recent observations: Clear dry weather at Mount St. Helens is permitting excellent visibility into the crater area. Small rock falls from the crater walls will occasionally kick up dust to the level of the crater rim. The extrusion of new rock into the lava dome continues unabated. The overall level of seismicity remains low. USGS field crews will be working on the volcano today installing new monitoring instrumentation.
September 12, 2006:
- 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 rising above the crater rim today would drift to the northeast.
- Recent observations: Images from remote cameras show that the extrusion of the new lava dome continues unabated, despite relatively low seismicity levels. Views from the US Forest Service web camera at the Johnston Ridge Observatory are clear this morning and show a small steam plume emanating from the new lava dome, as well as dust coming from minor rockfalls on the crater walls and the growing lava dome. Occasional larger rockfalls may produce ash clouds large enough to be visible from the Portland area. USGS field crews yesterday installed a new temporary camera ~500 feet from the active spine to enable high-spatial-resolution time-lapse analysis of lava dome extrusion, and also installed most of the infrastructure for a new permanent seismic station to be located on the southwest flank of the volcano. Field plans today include airborne gas & infrared measurements as well as helicopter-supported hydrology work.
September 13, 2006:
- 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 rising above the crater rim today would drift eastsoutheastward.
- Recent observations: The extrusion of the new lava dome continues unabated, despite relatively low seismicity levels. Views from the US Forest Service web camera at the Johnston Ridge Observatory are clear this morning and show a dusty day in the crater owing to minor rockfalls from the crater walls and the growing lava dome. Occasional larger rockfalls may produce ash clouds large enough to be visible from the Portland area.
September 14, 2006:
- 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 rising above the crater rim today would drift eastsoutheastward in the morning and eastward by evening.
- Recent observations: The extrusion of the new lava dome continues unabated, despite relatively low seismicity levels. A M 3.2 earthquake occurred just under the crater yesterday afternoon at 12:56 PDT. Fall weather is returning to Mount St.Helens with forecast snow and rain showers over the next couple of days. Views of the crater are obscured by clouds this morning.
September 15, 2006:
- 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 would drift to the southeast today.
- Recent observations: Extrusion of the new lava dome continues, despite relatively low seismicity levels. Views from the US Forest Service web camera at the Johnston Ridge Observatory are partly obscured by clouds this morning, but glimpses through the clouds reveal a light dusting of snow on the flanks of Mount St. Helens. The forecast for today calls for more snow and rain showers today and continued cool and cloudy weather through the first part of next week.
September 16, 2006:
- 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 would drift to the southeast today.
- Recent observations: Extrusion of the new lava dome continues, despite relatively low seismicity levels. Mount St. Helens was visible intermittently this morning on the US Forest Service webcam. The volcano was showing off the season’s first snowfall and a gently rising steam plume could be seen. Since yesterday afternoon, 4 small earthquakes M1.4 to M 2.7 have occurred beneath the crater floor.
September 17, 2006:
- 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 would drift southeasterly early today, changing to northeasterly by this evening.
- Recent observations: Data from deformation-monitoring instruments located on the 1980-86 and 2004-2006 lava domes indicate that extrusion of the new lava dome continues, despite relatively low seismicity levels. Mount St. Helens is visible this morning on the US Forest Service webcam, although clouds in the crater hide the new lava dome from view. With the five-day forecast calling for continued cloudy and occasionally stormy weather, views of the volcano will likely be intermittent over the next several days.
September 18, 2006:
- 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 would drift to the northeast today.
- Recent observations: Mount St. Helens is mostly hidden by clouds and precipitation this morning. However, data from deformation-monitoring instruments located on the 1980-86 and 2004-2006 lava domes indicate that extrusion of the new lava dome continues, despite relatively low seismicity levels. With the forecast calling for continued cloudy and occasionally stormy weather, views of the volcano will likely be intermittent over the next several days.
September 19, 2006:
- 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 rising above the crater rim today would drift to the northeast today.
- Recent observations: Mount St. Helens is mostly hidden by clouds and precipitation this morning. However, data from deformation-monitoring instruments located on the 1980-86 and 2004-2006 lava domes indicate that extrusion of the new lava dome continues, despite relatively low seismicity levels. With the forecast calling for continued cloudy and occasionally stormy weather, views of the volcano will likely be intermittent over the next several days.
September 20, 2006:
- 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 rising above the crater rim today would drift to the southeast.
- Recent observations: Remote cameras show occasional clearing in the crater this morning, and new snow, raising hopes for seasonal maintenance and crater fieldwork later this week. Seismicity continues at or near levels of the last few days to weeks.
September 21, 2006:
- 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 rising above the crater rim today would drift southeastward.
- Recent observations: Clouds obscure the crater today, but favorable forecasts suggest that by tomorrow afternoon the weather should be clear. There have been no changes in eruptive activity in the past 24 hours, and seismicity remains relatively low. A M2.9 earthquake at 12:52 pm local time yesterday may have been accompanied by rockfall. Events of this type are common under the current style of eruptive activity, and similar events are likely to occur again. Field crews hope to exploit the improving weather in the next few days.
September 22, 2006:
- 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 rising above the crater rim today would drift southward.
- Recent observations: The volcano is clear today above the valley fog. There have been no changes in eruptive activity in the past 24 hours, and seismicity remains in a relatively low state. Field crews will take advantage of today's clear weather to install another tiltmeter, retrieve some temporarily deployed broadband seismometers, adjust orientations of field cameras, and do some general maintenance and winterizing of instrumentation sites.
September 23, 2006:
- 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 rising above the crater rim today would drift southwestward.
- Recent observations: On this second anniversary of the start of unrest that culminated in the current eruption the mountain is clear and relatively quiet. Despite relatively low seismicity, the mountain continues to extrude lava that builds the new dome--lava which began emerging from the ground in October 2004. Field crews will be out again today finishing a tiltmeter installation, retrieving more portable seismometers, winterizing instrumentation sites, and sampling and collecting rocks from both the older parts of the mountain and the new lava dome.
September 24, 2006:
- 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 rising above the crater rim today would drift westward.
- Recent observations: The mountain remains quiet with clear weather conditions and excellent visibility. Lava continues to extrude onto the crater floor with low seismicity, generating occasional rockfalls as talus sloughs off the flanks of the growing dome. Yesterday field crews finished all installations, retrieved some seismometers and winterized others, and everyone arrived back safely, though quite late.
September 25, 2006:
- 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 rising above the crater rim today will not disperse widely, but instead will drift lazily around the mountain with a slight preference for an eastward to southeastward trajectory.
- Recent observations: Clear conditions at the mountain afford excellent visibility. The eruption continues unabated despite the relatively quiescent state of seismicity. Images from our remotely deployed cameras show that the currently active lava spine continues to emerge and push previously extruded material in a south-southwestward direction. Field crews will be out again today mapping older parts of the volcano, servicing instrumentation sites, and retrieving data from a camera deployed to capture fine-scale movement of the lava dome.
September 26, 2006:
- 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 rising above the crater rim today would drift southeastward.
- Recent observations: The mountain remains relatively quiet with clear weather conditions and superb visibility. A few small earthquakes and continued rockfall accompany the extrusion of lava onto the crater floor. Yesterday field crews installed a new broadband seismic station and fixed existing tiltmeter installations.
September 27, 2006:
- 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 rising above the crater rim today would drift westward.
- Recent observations: The volcano remains peaceful today, as clear weather conditions continue. There are minor rockfalls off of the new dome as lava emerges slowly from the vent. Seismicity is low, as are rates of deformation. The new dome is now nearly as high as Shoestring notch on the southeast crater wall.
September 28, 2006:
- 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 rising above the crater rim today would drift westward at low elevations and northward at high elevations.
- Recent observations: Quiescent conditions continue, as the volcano continues to extrude lava slowly from the vent. Seismicity is low, as are rates of deformation both near and far from the crater.
September 29, 2006:
- 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 rising above the crater rim today would drift southward at low elevations and westward above 10 km elevation.
- Recent observations: The mountain remains incredibly quiet as lava oozes passively onto the south crater floor, the only indication of activity being an occasional tiny earthquake and periodic rockfall from the growing dome. The weather remains remarkably clear, giving curious observers perfect viewing conditions.
September 30, 2006:
- 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 rising above the crater rim today would drift eastward.
- Recent observations: Yet another quiet day on the mountain, with steady but low seismicity and occasional rockfalls being the only indicator that lava is still extruding onto the south crater floor. There are a few high clouds but viewing remains excellent. Mount St. Helens is showing us that composite volcanoes can have passive eruptions too.
|
|
