Shishaldin volcano (Aleutian Islands, Alaska): ongoing 13th paroxysm episode, ash-rich emissions to 40,000 ft, alert level to Red

Ash emissions started to rise in the evening today, phoenix clouds seen resulted from glowing avalanches (image: AVO)

The intense eruptive period sustains at the volcano.
The 13th lava-fountaining sequence (paroxysm) followed a usual several-hours lasting strong seismic tremor, a typical precursor of rapid magma flux towards the summit. At 17:20 local time today, it culminated in constant dense ash emissions spewing tephra up to 40,000 ft (12 km) elevation to the east of the volcano. The Alaska Volcano Observatory (AVO) reported that the ash column was accompanied by volcanic lightning, suggesting ash-rich fine emissions in the plume. So-called dirty thunderstorms form when ash that is to be erupted begins as electrostatically neutral rock fragments. Heat and motion of fragmented material within volcano edifice is among the first source of particle charging, then another fundamental phenomenon to being charged is friction. In order to create volcanic lightning, neutrally charged ash particles must come in contact with another object of differently charged qualities.

The local alert level for the volcano was raised to RED.

Source: Alaska Volcano Observatory volcano activity update 3 October 2023