The self-protection recommendation announced yesterday for the population of El Paso, in the face of continuing unfavourable air quality with respect to PM10 concentrations, has been maintained. Residents should stay indoors as much as possible, particularly between 2pm-9pm local time, and wear an FFP2 mask if they must go outside. The active lava flows continue to advance slowly; the flow south of La Laguna Mountain is around 100 m from the coast, moving at 3-5 m per hour, and the northernmost flow is currently heading for the centre of La Laguna, although its path is less certain. Between the main cone and the ash vent that opened on the 16th October, a new vent opened in the afternoon, initially showing phreatomagmatic activity before transitioning into Stromolian activity. More findings from the chemical analysis of the lava have been published, showing the evolution from more differentiated to more primitive magma occurred contemporaneously with the hiatus of surface activity on the 27th September.

The eruption continues as in the previous days, with a Strombolian mechanism with a predominant effusive phase and a weaker explosive phase. More explosive activity continues to be concentrated in multiple vents within the main cone, and the effusive outlet is seen as a stepped lava channel that runs down the northern flank. The ash emission vent on the SE flank which reactivated on the 16th October continues intermittently. The active lava flow to the south of La Laguna Mountain, closest to the coast, has slowed to 2 m per hour and is currently 160 m from the coast. Elsewhere, advance of the flow front located just above La Laguna has largely stalled for the moment, although the flows continue to widen and thicken. Between 2pm-9pm local time, it was advised in El Paso that the population stay indoors due to unfavourable PM10 concentrations. This was due to the influence of the Saharan air mass, the ash from the volcano, and also the persistence of a low thermal inversion, which is expected to persist until the 22nd October. However, ash dispersion was more favourable than previous days with respect to the operation of La Palma airport.

The eruption continues to show a strombolian mechanism with mixed explosive and effusive phases, with the effusive phase remaining the stronger of the two currently. The main active lava flows are the two branches to the north of the original flows. The southern branch of this flow has surpassed La Laguna Mountain to the south and is currently approximately 200 m from the coast. In the event that this flow reaches the sea, PEVOLCA confirmed a confinement of the population in Todoque would be ordered, similar to when the first flows reached the sea. The northern branch of the active flow is located above La Laguna and continues to advance slowly. The unfavourable meteorological conditions for ash dispersion persist and are affecting the operation of La Palma airport and some airspace in between La Palma, La Gomera and Tenerife.

Although the effusive phase of the eruption continues to be more powerful currently than the more explosive strombolian phase, the active lava flow fronts are currently barely advancing. This is because of the existence of lava tubes, although the flows continue to widen and grow in height. Ashfall has been concentrated on the eastern side of the island to include the airport, and consequently airport operations have been affected and are expected to continue to be affected by the ash in the coming days. The lava flows currently cover 724 hectares, and at its widest the flow field is now 2,350 m wide. Regarding the 5 cm inflation seen at the Jedey LP03 station on the 14th October, that signal has now completely reversed, and the rest of the stations do not show significant deformation.

The eruption continues to show a mixed strombolian mechanism, with both explosive and effusive phases, although currently the effusive phase is the more predominant one. This has been observed downstream as an increase in fluidity of the active lava flows as a result of the greater supply rate of magma. During the night, the stream furthest north advanced at up to 250 m per hour, although it has slowed down to 20-30 m per hour. The area affected by lava is now 696 hectares, with the maximum width of the flow field 1,770 m. Regarding the inflation of 5 cm has been seen at the LP03 station between Jedey and Las Manchas yesterday, today it has shown a partial reversal, and no significant signals are seen in any of the other stations. During the afternoon, an old vent 300 m SE of the main cone reactivated although only with ash emission, and its activity decreased overnight.

New evacuations, on the night of the 13th and then on the morning of the 14th, have been ordered in La Laguna given the advance of the active lava flows to the north of the flow field. These have affected about 400 extra people, increasing the total number of evacuees from the eruption to around 6,400. The two branches of the northern-most lava flow are still active, with the wider southerly branch slowing down, but the more northern branch continues to advance towards La Laguna. Large blocks are observed being transported in the northern lava flow, which are remnants of small collapses of the cone. The eruption continues to show a strombolian mechanism with both explosive and effusive phases, producing pyroclastic deposits and lava flows.

The lava flows to the north of the flow field that prompted the evacuation La Laguna on the 12th continue to advance, but in an uneven fashion. The furthest north branch of these flows, which was the one of main concern, is losing power and is advancing only slowly. However, the southern of these flows is currently the most active stream, and advances at approximately 50 m per hour. The current affected area of the lava flows is 640 hectares, 28 more than the previous day, and the maximum width of the lava flow field is 1,770 m. However, it was also stressed by PEVOLCA that the eruption is currently affecting only 8% of the island including areas affected by significant ashfall, and that the area covered by lava flows is still <1% of the land area of the island. Regarding eruptive activity, Strombolian activity is still seen from multiple vents within the main cone, and a reactivation of a more effusive vent on the SE flank of the main cone has been confirmed. Pulses of phreatomagmatic activity can also be seen.

The confinement of several areas on the morning of the 11th due to the cement factory fire was lifted in the morning as the lava front has surpassed the sight and the air quality was assessed to be safe. However, further permanent evacuations of people were ordered in the morning by PEVOLCA, affecting 700-800 people in and around the settlement of La Laguna, due to the advancing lava flows to the north that affected the Callejón de la Gata industrial estate. There are two active lava flows, one that travels parallel and northwest of the original flow, and the second which prompted the new evacuation as moves very quickly. The original flows to the south, including the lava delta, remain inactive for now. Results from preliminary chemical and petrographic analyses of the lava flows and pyroclasts have been published for the first time, showing an evolution of the magma throughout the eruption from a more differentiated to a more primitive composition in the baseite-tephrite series. This is consistent with known historical eruptions on La Palma.

A confinement of several population centres in Los Llanos de Aridane and El Paso totalling 3,500 people was ordered in the morning, due to the release of toxic gases from a large fire in a cement factory in the Callejón de la Gata industrial park, ignited by the northern active lava flow. There are currently three active lava streams: the original one feeding the lava delta, one to the south of the lava delta on the delta from the 1949 eruption, and the stream to the north which consists of two branches. The stream to the north currently has the greatest supply of lava, and has one branch affecting the industrial park, whilst the other branch is covering new ground in the direction of Todoque Mountain. To the north of Todoque mountain, the original stream is 300 m away from the coast and could form a second lava delta in the coming days if the supply of lava continues.

The lava flows to the north of the lava flow field have been expanded as a result of the increased effusive activity caused by the rupture of the cone, including a lava flow that is covering new ground and is heading towards the part of Todoque not previously affected by the main lava flows. There are two branches of this flow, one to the south that has joined the previous flow, and one to the north which is travelling through the industrial estate and cement factory west of the town of La Laguna. At 2:30 pm local time, there was another partial collapse of the crater wall, releasing a large volume of lava as well as large blocks of the crater which were transported away by the lava flows. Currently, the lava exceeds 526 hectares, and the maximum width has also increased to 1,520 metres. The latest figures on destruction from Copernicus indicate 1,281 buildings affected, with 1,186 of those destroyed.