OVSICORI-UNA reported that seismic and infrasound data indicated multiple events at Poás during 7-8 February.
On 8 February events were centered at vent A (Boca Roja) and produced plumes that rose no higher than 200 m and drifted SW.
A sulfur dioxide odor was reported in areas downwind including San Jose de Naranjo, Grecia (16 km SW), Poás, Sarchá, Naranjo, and Atenas (32 km SW).
Incandescence in the crater began to be visible at 0151 on 11 February.
Passive ash emissions rose 200 m and drifted SW.
Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA)