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September 1, 2007:
- Current Volcanic- Alert Level WATCH; 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 northeastward.
- 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: Another beautiful day at Mount St. Helens provides excellent viewing into the crater. Seismicity and deformation remain unchanged as lava continues to extrude onto the south crater floor. There have been no significant changes in the last 24 hours.
- *** This line included in daily update but excluded for rest of month on this page.
September 2, 2007:
- Current Volcanic- Alert Level WATCH; 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.
- Recent observations: Warm and clear conditions provide good viewing into the crater today. Seismicity and deformation are consistent with continued extrusion of lava onto the south crater floor. No significant changes have occurred in the last 24 hours.
September 3, 2007:
- Current Volcanic- Alert Level WATCH; 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 northeast.
- Recent observations: Warm and mostly clear conditions provide views into the Mount St. Helens crater this morning. Subtle but regular seismicity associated with continued lava-dome growth and sporadic ground-shaking due to occasional rock falls continues with extrusion of lava onto the south crater floor. No significant changes have occurred in the last 24 hours.
September 4, 2007:
- Current Volcanic- Alert Level WATCH; 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 northeast early in the day and south-southeast later in the day.
- Recent observations: The crater is partly obscured by low clouds this morning. Volcano activity continues with on-going seismicity, deformation, and rockfalls from the crater walls and growing dome. There have been no significant changes in conditions over the last 24 hours.
September 5, 2007:
- Current Volcanic- Alert Level WATCH; 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 south early in the day and south-southeast later in the day.
- Recent observations: The crater is partly obscured by low clouds this morning. Volcano activity continues with on-going seismicity, deformation, and rockfalls from the crater walls and growing dome. Last week, crews installed a new GPS spider on spine 4 of the new lava dome, decommissioned the Yellow Rock seismic station, which was threatened by rock and ice fall from the advancing west lobe of the Crater Glacier, and removed no-longer-serviceable equipment from a monitoring site on the 1980-86 lava dome. There have been no significant changes in conditions over the last 24 hours.
September 6, 2007:
- Current Volcanic- Alert Level WATCH; 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-southeastward.
- Recent observations: The crater is obscured by low clouds this morning. Volcano activity continues with on-going seismicity, deformation, and rockfalls from the crater walls and growing dome. There have been no significant changes in conditions over the last 24 hours.
September 7, 2007:
- Current Volcanic- Alert Level WATCH; 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 crater is partly obscured by low clouds this morning. Volcano activity continues with on-going seismicity, deformation, and rockfalls from the crater walls and growing dome. There have been no significant changes in conditions over the last 24 hours.
September 8, 2007:
- Current Volcanic- Alert Level WATCH; 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: Warm and clear conditions provide views into the Mount St. Helens crater this morning. Volcano activity continues with on-going seismicity, deformation, and rockfalls from the crater walls and growing dome. There have been no significant changes in conditions over the last 24 hours.
September 9, 2007:
- Current Volcanic- Alert Level WATCH; 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 south-southwest.
- Recent observations: Warm and clear conditions provide views into the Mount St. Helens crater this morning. Volcano activity continues with on-going seismicity, deformation, and rockfalls from the crater walls and growing dome. There have been no significant changes in conditions over the last 24 hours.
September 10, 2007:
- Current Volcanic- Alert Level WATCH; 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-southwest.
- Recent observations: Warm and clear conditions provide views into the Mount St. Helens crater this morning. Volcano activity continues with on-going seismicity, deformation, and rockfalls from the crater walls and growing dome. There have been no significant changes in conditions over the last 24 hours.
September 11, 2007:
- Current Volcanic- Alert Level WATCH; 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 East.
- Recent observations: It's a warm, sunny, late-summer day in the Pacific Northwest. Camera views show the mountain to be clear with a light dust and ash plume drifting over the east rim. Monitored parameters are essentially unchanged in the last 24 hours. Slow steady extrusion of the lava dome in the crater continues unabated.
September 12, 2007:
- Current Volcanic- Alert Level WATCH; 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 East.
- Recent observations: Although this morning brought low overcast to the Vancouver area, camera views show skies at Mt. St. Helens to be clear and sunny. A thin plume is rising from the growing lava dome and drifting with the prevailing winds to the East over the crater rim. No significant changes in the volcano's behavior have been noted overnight. Volcano activity continues with on-going seismicity, deformation, and rockfalls from the crater walls and growing dome.
September 13, 2007:
- Current Volcanic- Alert Level WATCH; 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 west.
- Recent observations: The sky is clear at the volcano, although fog persists in the valley. From the USFS camera at Johnston Ridge, dust plumes can be seen in the crater and drifting above the crater rim due to wind remobilizing old ash and other fine-grained material. This is a common occurrence when we have stretches of hot dry weather has we have had this past week. Low-level earthquake activity and rates of deformation continue to accompany the extrusion of the lava dome.
September 14, 2007:
- Current Volcanic- Alert Level WATCH; 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-southwest.
- Recent observations: Onshore flow of marine air across the region today has caused overcast skies in Vancouver and shrouded Mt. St. Helens in clouds. There have been no significant changes in monitored parameters overnight. Slow steady dome extrusion accompanied by occasional earthquakes and the possibility of small landslides from the growing dome is continuing.
September 15, 2007:
- Current Volcanic- Alert Level WATCH; 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: Mount St. Helens is socked in clouds this morning. Small earthquakes and occasional rockfalls accompany continued slow growth of the lava dome. There have been no significant changes in conditions over the last 24 hours.
September 16, 2007:
September 17, 2007:
- Current Volcanic- Alert Level WATCH; 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 views of the crater today, but small earthquakes and slow ground deformation indicate ongoing extrusion of the lava dome. There have been no significant changes in conditions over the last 24 hours.
September 18, 2007:
- Current Volcanic- Alert Level WATCH; 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 east.
- Recent observations: The crater is obscured by clouds and precipitation this morning. Monitoring instruments continue to record small earthquakes and steady ground deformation consistent with extrusion of the lava dome. There have been no significant changes in conditions over the last 24 hours.
September 19, 2007:
- Current Volcanic- Alert Level WATCH; 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 southwest.
- Recent observations: Views from remote cameras this morning feature a light dusting of snow that fell overnight at elevations above the crater floor. Wispy clouds are currently attached to the east and southwest sides of the crater rim, likely in part caused by condensation from melting of the freshly fallen snow. Seismicity continues to be at low but above-background levels, and is dominated by rockfalls from the growing new dome and noises generated by the rapidly moving Crater Glacier.
September 20, 2007:
- Current Volcanic- Alert Level WATCH; 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 south-southwest early, with a shift to the southeast later in the day.
- Recent observations: A higher cloud ceiling affords the opportunity for fieldwork at the mountain today. Crews will be mapping, deploying and maintaining seismic instrumentation, and collecting samples over the next two days, weather permitting. Monitoring instruments continue to record small earthquakes, rock falls and steady ground deformation consistent with on-going extrusion of the lava dome. There have been no significant changes in conditions over the last 24 hours.
September 21, 2007:
- Current Volcanic- Alert Level WATCH; 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 east-southeast.
- Recent observations: Clear weather this morning affords a spectacular view of the volcano, from which a small gas plume can be seen near the top of the new lava dome. Seismicity levels remain low and consistent with continued slow extrusion of new lava. Field crews yesterday had their work day cut short by inclement weather. Today crews are hoping to continue geologic mapping efforts, repair/move several pieces of monitoring equipment, retrieve rock samples from the new lava dome, and measure gas compositions in the plume.
September 22, 2007:
- Current Volcanic- Alert Level WATCH; 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 east.
- Recent observations: The crater is not visible from Johnston Ridge early this morning, though the weather may improve later in the day. Monitoring instruments continue to record small earthquakes, rock falls and steady ground deformation consistent with on-going extrusion of the lava dome. There have been no significant changes in conditions over the last 24 hours.
September 23, 2007:
- Current Volcanic- Alert Level WATCH; 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 south-southeast.
- Recent observations: Three years ago at 2 a.m. PDT seismometers at Mount St. Helens recorded the start of an earthquake swarm that heralded the reawakening of the volcano after an almost-18-year-long slumber. Today the eruption continues, with the total erupted volume exceeding that of the “old dome” formed by eruptions in 1980-86. Seismicity, deformation, and extrusion rates are all significantly lower than those encountered during the first months of the eruption in 2004, but seismicity remains above background levels and time-lapse images show that new lava continues to reach the surface. Clouds are currently hiding the 3-year-old eruption from view of cameras at the Johnston Ridge Observatory, but a partly-cloudy forecast gives reason for hope of improving viewing conditions as the day matures.
September 24, 2007:
- Current Volcanic- Alert Level WATCH; 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 south-southeast.
- Recent observations: A crystal-clear sky greets the morning at the volcano, enabling viewers of Johnston Ridge Observatory web cameras to see the principal steam/gas plume as it emanates from the top of the new lava dome and gently wafts over the south crater rim. Seismicity remains low but above background levels, consistent with ongoing extrusion of new lava.
September 25, 2007:
- Current Volcanic- Alert Level WATCH; 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 south to southeastward.
- Recent observations: The volcano is obscured by a low cloud cover today. Seismicity and deformation remain unchanged over the last 24 hours, and indicate that lava extrusion continues.
September 26, 2007:
- Current Volcanic- Alert Level WATCH; 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 to southeastward.
- Recent observations: The mountain is clear and beautiful this morning, with a small amount of steam and gas rising from the vent. Lava extrusion continues, and deformation and seismic signals indicate no substantial changes in the last 24 hours.
September 27, 2007:
- Current Volcanic- Alert Level WATCH; 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.
- Recent observations: Clear conditions this morning offer good views of the mountain and the growing lava dome. Occasional small earthquakes and dome growth continue. Yesterday, field crews conducted surveys of stream channels, worked on geological mapping, and did instrumentation maintenance in advance of the coming winter season.
September 28, 2007:
- Current Volcanic- Alert Level WATCH; 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 broadly east-northeastward early in the day, switching to a southeastwardly trajectory later in the day.
- Recent observations: Stormy weather envelopes the mountain this morning. A relatively large (probably M3+), shallow, near-surface earthquake at 11:19 am (PDT) yesterday generated a small dust plume (from rockfall) that rose above the rim. Such quakes, while now relatively rare, are not unusual for the type of ongoing dome-growth eruption occurring at the volcano.
September 29, 2007:
- Current Volcanic- Alert Level WATCH; 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: There is clear viewing into the crater this morning, with a fresh blanket of snow down to about the 4000 foot level. Lava extrusion continues, with occasional earthquakes and rockfall. No significant changes have occurred in the last 24 hours.
September 30, 2007:
- Current Volcanic- Alert Level WATCH; 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 to northeastward.
- Recent observations: Stormy weather with potentially heavy rains envelope the mountain today. Under these conditions, small, localized debris flows can be triggered, and sediment movement along the North Fork Toutle River can cause muddy plumes along the lower Toutle River. Seismicity at the volcano remains the same as in recent days, with small earthquakes indicative of rockfall, glacier motion, and ongoing intrusion of magma into the growing lava dome.
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