Undated photo of Shiveluch volcano in Russia.
In case you haven't seen the report yet, Shiveluch in Kamchatka has gone, as they say, "non-linear". KVERT has raised the alert level at the volcano to "Red" with reports of many strong explosions and an ash plume of >32,800 feet / >10 km. This all suggests that the volcano might have experienced [WARNING SPECULATION] a massive dome collapse followed by rapid decompression of the magma under the dome - causing the plinian eruption that seems to be underway. The size of this eruption plume will definitely have some effect on air travel over the region from North America and Europe. More details as they arrive.
The full KVERT alert is as follows:
KVERT INFORMATION RELEASE 51-09 Thursday, September 10, 2009, 20:50 UTC (Friday, September 11, 09:50 KDT)
SHEVELUCH VOLCANO: 56°38'N, 161°19'E; Elevation 3,283 m, the dome elevation ~2,500 m CURRENT AVIATION COLOR CODE IS RED PREVIOUS AVIATION COLOR CODE WAS ORANGE
Strong explosive eruption of Sheveluch volcano with ash explosions >10 km (>32,800 ft) ASL probably continues. The activity of the volcano could affect international and low-flying aircraft.
According to seismic data, strong explosions of Sheveluch volcano occurred from ~14:19 to ~14:55 UTC on September 10. According to an interpretation of seismic signals, ash plumes rose up to >15,000 m (> 49,200 ft) ASL.
Next seismic signals detected a movement (during 8 minutes) of pyroclastic flows from the lava dome of the volcano at 15:57 UTC on September 10. Ash plumes from pyroclastic flows rose up to ~10,000 m (~32,800 ft)ASL (according to seismic signals).
No visual and satellite data about this events - the volcano obscures by clouds.