INSIVUMEH reported that effusive activity at Fuego decreased as of 16 September; the lava flow that had descended the Ceniza drainage (SSW) was no longer active.
There were 6-16 explosions per hour recorded during 16-22 September, generating ash plumes as high as 1.1 km above the crater rim that generally drifted 7-20 km in multiple directions.
Shock waves rattled buildings within a 20-km radius.
Sometimes incandescent material ejected 100-300 m high caused avalanches of blocks in the Ceniza, Seca (W), Trinidad (S), Taniluyá (SW), Las Lajas, and Honda drainages; avalanches sometimes reached vegetated areas.
Ashfall was reported daily in several areas downwind including Morelia (9 km SW), Panimaché I and II (8 km SW), Finca Palo Verde, Santa Sofía (12 km SW), San Pedro Yepocapa (8 km NW), and Sangre de Cristo (8 km WSW).
During 18-19 September lahars descended the Ceniza, Las Lajas, and Honda drainages, carrying tree branches, trunks, and blocks as large as 1.5 m in diameter.
Additionally, lava flows traveled 200-350 m down the Seca and Ceniza drainages.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)