OVSICORI-UNA reported that low-to-moderate amplitude tremor was recorded at Turrialba during 17-23 May.
Small numbers of volcano-tectonic and long-period events were recorded during 18-19 May, and low-frequency and volcano-tectonic events were detected during 21-22 May.
Ash emission were observed during 17-23 May, rising as high as 1 km above the vent.
Ashfall was reported in El Tapojo and Juan Viñas (15 km SSE) during 17-18 May, and in Capellades (along with a strong sulfur odor) during 19-20 May.
Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA)