"On 19 May seismicity at Fuego increased and explosions were heard at 5-10 minute intervals. A 600-m-long lava flow descended the W flank, and a 1-km-long and 20-m-wide lava flow descended the E flank, reaching the base of the volcano. Explosions ejected incandescent tephra 400 m above the crater, and produced ash plumes that rose 5 km above the crater and drifted 30 km S and SW. Coordinadora Nacional para la Reducción de Desastres (CONRED) raised the Alert Level to Orange (the second highest level on a 4-color scale). Pyroclastic flows also descended the flanks, prompting authorities to restrict passage on part of a highway. Ash plumes from the pyroclastic flows rose 3 km above the crater. Ashfall was reported in Morelia (7 km SW), Panimaché I and II (9 km SW), Sangre de Cristo (8 km WSW), and Yepocapa (8 km WNW). Thirteen people from El Porvenir in Alotenango (8 km ENE) evacuated to local shelters. Visual observations and seismicity indicated that activity decreased later that day.
On 20 May a few explosions generated ash plumes that rose 500 m above the crater and drifted 8 km SW. The next day cloud cover prevented observations; however explosions, rumbling, and degassing sounds were reported. On 22 May explosions generated ash plumes that rose as high as 1 km and drifted 10 km S and SE. Rumbling was heard and shock waves were detected. The lava flows were inactive and only incandescence from block avalanches was observed." [less]

The eruption was both explosive and effusive. According to news, the eruption began at 2:45 a.m. with large explosions and lava fountains possibly up to 1 km high from the summit crater. Large incandescent bombs were ejected to considerable distances and showered the summit cone of the volcano. A 500 m long lava flow traveled down on the SW flank towards the Ceniza ravine. The eruption also produced an ash column reaching 5 km (16,000 ft altitude) and pyroclastic flows probably generated mostly by cascading lava blocks traveling down the steep cone's flank into Las Lajas, El Jute y Ceniza valleys.
Ash fall was reported from nearby villages mainly to the S and SW including Morelia, Panimaché I and II, Sangre Cristo and Yepocapa. [less]

Explosions produced shock waves detected within 8 km of the volcano. Avalanches descended the flanks. [less]

During the night lava fountains rose 100-150 m above the crater and formed avalanches that traveled towards the Río Cenizas drainage. Based on analysis of satellite imagery, the Washington VAAC reported that on 1 April an ash plume drifted 13 km WSW and a well-defined thermal anomaly was observed.
(Smithsonian / USGS Weekly Volcanic Activity Report) [less]

(USGS / weekly activity update) [less]

The lava flow in the direction of Taniluyá is between 150-200 m long, and incandescent blocks detach from the front, tumbling down into the forested area. [less]

The lava flow in the direction of Taniluyá is between 150-200 m long, and blocks detach from the front, tumbling down into the forested area. (source: INSIVUMEH)
[less]

The new lava flow on the southwest flank in the direction of the Taniluya ravine is still active and about 200 m long. Blocks that detach from its front form small block avalanches that reach the vegetation. [less]

Rock avalanches traveled SW into the Ceniza drainage and on the W, S, and SW flanks. At night on 13 and 16 January incandescence was visible from the crater.
(Source: Smithsonian / GVP weekly activity report) [less]