During 30 June-14 July, INSIVUMEH frequently reported a white fumarolic plume rising from Fuego’s summit extending up to 4,000 m (13,123 ft) a.s.l.. Weak-to-moderate explosions generated ash plumes to similar heights during 30 June and 1, 4, 6, 7, and 9-13 July. Rumbling and jetting sounds often accompanied these explosions, often with durations of 1-5 minutes. Pulses of incandescence reached 50-100 m above the rim on 30 June, and 6, 7, and 12 July. Remobilized ash reduced visibility on 4, 9, and 10 July. Surges of lava and incandescent avalanches traveled from the summit down the flanks on 1 July (~150 m into the Trinidad drainage), 6 July (100 m into Taniluya and 200 m into the Ceniza), 11 July (~100 m into Taniluya), 12 July (Santa Teresa, Taniluya, Ceniza, Trinidad, Las Lajas, and Honda), and 13 July (~400 m into the Ceniza).

Geological Summary. Volcán Fuego, one of Central America's most active volcanoes, is also one of three large stratovolcanoes overlooking Guatemala's former capital, Antigua. The scarp of an older edifice, Meseta, lies between Fuego and Acatenango to the north. Construction of Meseta dates back to about 230,000 years and continued until the late Pleistocene or early Holocene. Collapse of Meseta may have produced the massive Escuintla debris-avalanche deposit, which extends about 50 km onto the Pacific coastal plain. Growth of the modern Fuego volcano followed, continuing the southward migration of volcanism that began at the mostly andesitic Acatenango. Eruptions at Fuego have become more mafic with time, and most historical activity has produced basaltic rocks. Frequent vigorous historical eruptions have been recorded since the onset of the Spanish era in 1524, and have produced major ashfalls, along with occasional pyroclastic flows and lava flows.

Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)