Activity at Okmok has dampened a bit though there is still a ash cloud up to 25K feet. Cleveland hasn’t been visible for a day or 2 but satellite imagry suggests there’s lava present on the surface.  For an update on the Chaiten eruption in Chile check out Dr. Erik Klemetti’s blog: Eruptions.

Taken from Ft Glenn on the east flank of Okmok Caldera. Courtesy of Lonnie Kennedy

AVO/USGS Volcanic Activity Notice

Volcano: Okmok

Current Volcano Alert Level: WARNING

Current Aviation Color Code: RED

Issued: Friday, July 25, 2008, 1:47 PM AKDT (20080725/2147Z)
Source: Alaska Volcano Observatory
Notice Number: 2008/A15
Location: N 53 deg 23 min W 168 deg 9 min
Elevation: 3520 ft (1073 m)
Area: Aleutians Alaska

Volcanic Activity Summary: The amplitude of seismic activity has increased in the past hour. Two pilots report ash to 40,000 feet. Satellite data confirm ash to at least 35,000. Based on these observations AVO is increasing the aviation color code at Okmok volcano to RED, and the alert level to WARNING.

Recent Observations:
[Monitoring report] Seismicity accelerated markedly about 12:30 pm today and remains at high levels.
[Other volcanic cloud information] Pilot reports and satellite data suggest ash cloud heights of 35,000 to 40,000 feet. Forecast winds would carry ash generally to the SE.

Hazard Analysis:
[Ash cloud] Pilot reports and satellite data suggest ash cloud heights of 35,000 to 40,000 feet. Forecast winds would carry ash generally to the SE.
[Ash fall] Minor ashfall may occur around the caldera, on the eastern portions of Umnak Island, and to the southeast of the island.
[Pyroclastic flow] The increased intensity of activity suggests that the likelihood of pyroclastic flow activity within the caldera has increased.
[Mud flow] Ongoing eruptions of ash are loading the upper slopes of Okmok Volcano with debris. Rainfall could mix with this ash fall to form mudflows and flooding especially on the eastern flank and eastern drainages from the Okmok caldera rim.

Remarks: Please see http://www.avo.alaska.edu/activity/Okmok.php for more information.

The nearest settlements are Nikolski, population about 35, roughly 45 miles west of the volcano, and a small number of people at the abandoned Fort Glenn military base 10 miles east of the volcano.

Contacts: John Power, Acting Scientist-in-Charge, USGS
jpower@usgs.gov, (907)786-7497

Steve McNutt, Coordinating Scientist, UAFGI
steve@giseis.alaska.edu (907)978-5458

Next Notice: A new VAN will be issued if conditions change significantly or alert levels are modified. While a VAN is in effect, regularly scheduled updates are posted at http://www.avo.alaska.edu

The Alaska Volcano Observatory is a cooperative program of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute, and the Alaska Division of Geological and Geophysical Surveys.

CLEVELAND VOLCANO
52°49′20″ N 169°56′42″ W, Summit Elevation 5676 ft (1730 m)
Current Aviation Color Code: ORANGE
Current Volcano Alert Level: WATCH

The eruption of Cleveland Volcano continues. Partly cloudy satellite data show a low level ash cloud at the height of the volcano’s summit since 5:48 ADT (13:48 UTC) today. A strong thermal anomaly near the summit persists, indicating active lava flow on the surface.

Please see http://www.avo.alaska.edu/activity/Cleveland.php for more information.

OKMOK VOLCANO
53°23′49″ N 168°9′58″ W, Summit Elevation 3520 ft (1073 m)
Current Aviation Color Code: ORANGE
Current Volcano Alert Level: WATCH

The eruption of Okmok Volcano continues. Nearly continuous, mid-level volcanic tremor has persisted since yesterday. Satellite data show an intermittent ash plume drifting away from Okmok toward the E/SE. Satellite thermal data suggest the presence of a low level thermal anomaly.

Stronger explosive activity could resume at any time with little or no warning.

Please see http://www.avo.alaska.edu/activity/Okmok.php for more information.

Please see http://www.avo.alaska.edu/color_codes.php for complete definitions of Aviation color codes and Volcano alert levels.

VOLCANO INFORMATION ON THE INTERNET: http://www.avo.alaska.edu
RECORDING ON THE STATUS OF ALASKA’S VOLCANOES (907) 786-7478

CONTACT INFORMATION:
John Power, Acting Scientist-in-Charge, USGS
jpower@usgs.gov, (907)786-7497

Steve McNutt, Coordinating Scientist, UAFGI
steve@giseis.alaska.edu (907)978-5458

The Alaska Volcano Observatory is a cooperative program of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute, and the Alaska Division of Geological and Geophysical Surveys.

CLEVELAND VOLCANO
52°49′20″ N 169°56′42″ W, Summit Elevation 5676 ft (1730 m)
Current Aviation Color Code: ORANGE
Current Volcano Alert Level: WATCH

Thick clouds have obscured satellite views of Cleveland for the last 10 hours. No plumes have been visible in satellite data since 16:00 AKDT yesterday (midnight UTC). Satellite data from early yesterday evening continue to show strong thermal anomalies near Cleveland’s summit. These data strongly suggest the presence of lava at Cleveland.

Please see http://www.avo.alaska.edu/activity/Cleveland.php for more information.

OKMOK VOLCANO
53°23′49″ N 168°9′58″ W, Summit Elevation 3520 ft (1073 m)
Current Aviation Color Code: ORANGE
Current Volcano Alert Level: WATCH

The eruption of Okmok Volcano continues. The character of seismicity has changed in the last 12 hours from episodic, high-amplitude pulses to nearly continuous, mid-level volcanic tremor. Recent satellite data continue to show older plumes drifting away from Okmok toward the E/SE. Weather clouds have prevented unobscured views of the volcano over the last 10 hours.

Stronger explosive activity could resume at any time with little or no warning.

Please see http://www.avo.alaska.edu/activity/Okmok.php for more information.

CLEVELAND VOLCANO
52°49′20″ N 169°56′42″ W, Summit Elevation 5676 ft (1730 m)
Current Aviation Color Code: ORANGE
Current Volcano Alert Level: WATCH

Recent satellite data show a >50 km steam plume, possibly containing some ash, drifting E/SE at between 10,000 and 20,000 feet above sea level. Satellite data also show a strong thermal anomaly at Cleveland, which may indicate a lava flow. However, AVO has as of yet received no eyewitness reports of lava at Cleveland.

Please see http://www.avo.alaska.edu/activity/Cleveland.php for more information.

Okmok eruption 20 July 08

OKMOK VOLCANO
53°23′49″ N 168°9′58″ W, Summit Elevation 3520 ft (1073 m)
Current Aviation Color Code: ORANGE
Current Volcano Alert Level: WATCH

The eruption of Okmok Volcano continues. Seismicity increased overnight from around midnight to 03:00 AKDT (08:00 – 11:00 UTC), but has declined somewhat since then. Currently, seismicity consists of episodic pulses occasionally grading into continuous volcanic tremor.

Recent satellite data show plumes of steam and/or ash drifting E/SE within 50 km of Okmok at between 20,000 and 30,000 feet above sea level.

Stronger explosive activity could resume at any time with little or no warning.

Please see http://www.avo.alaska.edu/activity/Okmok.php for more information.

CONTACT INFORMATION:
John Power, Acting Scientist-in-Charge, USGS
jpower@usgs.gov, (907)786-7497

Steve McNutt, Coordinating Scientist, UAFGI
steve@giseis.alaska.edu (907)978-5458

The Alaska Volcano Observatory is a cooperative program of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute, and the Alaska Division of Geological and Geophysical Surveys.

Cleveland Eruption 2006

Image provided by NASA Earth Observatory

Cleveland Volcano is also located in Aleutian Islands of Alaska and has been under watch status for sometime. Appearantly there was a small eruption today. More as it develops….

CLEVELAND VOLCANO
52°49′20″ N 169°56′42″ W, Summit Elevation 5676 ft (1730 m)
Current Aviation Color Code: ORANGE
Current Volcano Alert Level: WATCH

Reports from fishing boats indicate an eruption of Cleveland volcano occurred at approximately 12:00 AKDT (20:00 UTC). These reports also indicate that at sea level the ash may be moving to the northwest. Reports from pilots indicate a plume of ash and steam reaching roughly 15,000 – 17,000 feet above sea level in the vicinity of Cleveland and moving to the southeast. Pilots also report surface ash extending up to 50 miles southeast of the event.

Stronger explosive activity could resume at any time with little or no warning.

Please see http://www.avo.alaska.edu/activity/Cleveland.php for more information.

OKMOK VOLCANO
53°23′49″ N 168°9′58″ W, Summit Elevation 3520 ft (1073 m)
Current Aviation Color Code: ORANGE
Current Volcano Alert Level: WATCH

The eruption of Okmok Volcano continues. Seismicity remains episodic in character and well above background levels. Reports from pilots indicate a plume of ash and steam is reaching roughly 24,000 feet above sea level and moving to the southeast.

Stronger explosive activity could resume at any time with little or no warning.

Please see http://www.avo.alaska.edu/activity/Okmok.php for more information.

CONTACT INFORMATION:
John Power, Acting Scientist-in-Charge, USGS
jpower@usgs.gov, (907)786-7497

Steve McNutt, Coordinating Scientist, UAFGI
steve@giseis.alaska.edu (907)978-5458

The Alaska Volcano Observatory is a cooperative program of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute, and the Alaska Division of Geological and Geophysical Surveys.