La Palma volcano update: Sudden large explosion today sends ash to 5,000 m altitude

Around noon local time, a sudden large explosion occurred at the main crater of the cone, producing a steam and ash plume that quickly rose to estimated 5,000-6,000 meters altitude.
The event was likely a so-called vulcanian explosion, typically caused when a larger plug in the upper conduit has formed and is suddenly thrown out when gas pressure underneath overcomes a threshold (comparable to a cannon-shot mechanism).
Today's explosion likely might be due to the fact that the conduits have gradually been closing up / filling with debris in their upper parts as supply of rising material is less abundant. This fits with the model that the eruption has entered its final waning stage, but also creates highly dangerous conditions, because such explosions could (and likely will) repeat in the days to come.

Intensa columna de ceniza a las 12.00 hora canaria. Vídeo registrado desde el embalse Dos Pinos / Intense column of ash at 12.00 pm Canarian time. Video recorded from Dos Pinos dam pic.twitter.com/wsaoObxEGt

— INVOLCAN (@involcan) December 12, 2021

Apart from this, the eruption - now on its 85th day of activity being the longest in recorded history on La Palma Island - has continued at low levels similar as in the past days. There is now mainly steaming, with only occasional smaller explosions, at the main cone, while lava effusion continues at reduced rate. The arriving lava first goes into the tube system, and feeding flows in similar areas as during the past days overlapping older flows.
Seismic activity has been low, with only 24 quakes detected during 24 horus, the maximum being only a 3.2 event. Deformation and tremor remain basically unchanged at low values, although the explosion earlier resulted in a short-lived intense tremor peak.