KVERT reported that during 23-30 July seismic activity from Gorely was above background levels and volcanic tremor continued to be detected. A daily thermal anomaly on the volcano was seen in satellite imagery. Gas-and-steam activity was noted during 26-27 July. The Aviation Color Code level remained at Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

During 28 July-3 August HVO reported that activity at Kīlauea continued from the summit and the east rift zone. At the summit, the level of a lava-pool surface in the deep pit within the floor of Halemaʻumaʻu crater remained mostly stable; glow from the vent was also visible at night. A plume from the vent mainly drifted SW, dropping small amounts of ash downwind.

At the east rift zone, lava flows that broke out of the TEB lava-tube system advanced NE over coastal highway 137 towards Kalapana Gardens subdivision. Two lava lobes that had overtopped the Hakuma horst, SW of Kalapana Gardens, flowed into the ocean. The first flow initially entered the ocean on 25 July and continued to build a small delta that was about 500 m wide by 3 August. On 28 July, the second flow entered the ocean, about 545 m E of the first ocean-entry point. In addition to the activity near the ocean, scattered small active lobes of lava were seen about 1 km W of the highway 130/137 intersection.

Source: US Geological Survey Hawaiian Volcano Observatory (HVO)

INGEOMINAS reported that periodically during 26 July-3 August sulfur dioxide plumes from Nevado del Huila were observed by ground-based instruments as well as satellite imagery. During 28-30 July INGEOMINAS noted that ash emissions reported by the Washington VAAC corresponded with increased seismicity. On 28, 30, and 31 July and 1 August gray fumarolic plumes drifting W were seen through the web camera at Tafxnú as well as a new web camera installed at Maravillas (12 km SE of Pico Central). The Alert Level remained at III (Yellow; "changes in the behavior of volcanic activity").

Source: Servicio Geológico Colombiano (SGC)

RVO reported that GPS data measurements showed deflation of Rabaul caldera's Tavurvur cone after the eruption that took place during 23-25 July. Seismicity was very low, and diffuse white plumes were emitted during 26-30 July.

Source: Rabaul Volcano Observatory (RVO)

Based on information from JMA, the Tokyo VAAC reported an explosion on 29 July. Explosions during 31 July-1 August and 3 August produced plumes that rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted E and SW. On 2 July a pilot observed an ash plume that rose to an altitude of 3 km (10,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)

Based on analyses of satellite imagery, the Darwin VAAC reported that during 30-31 July an ash plume from Batu Tara drifted 65 km NW at an altitude of 1.5 km (5,000 ft) a.s.l.

Source: Darwin Volcanic Ash Advisory Centre (VAAC)

Based on analyses of satellite imagery and web camera footage, the Buenos Aires VAAC reported that a plume from Chaitén's lava-dome complex drifted 20 km ENE on 30 July. An 18-km-wide ash plume also drifted 45 km ESE.

Source: Buenos Aires Volcanic Ash Advisory Center (VAAC)

Based on analyses of satellite imagery, the Darwin VAAC reported that on 31 July an ash plume from Dukono rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted over 90 km W. A diffuse ash plume drifted 130 km NNE on 3 August at the same altitude.

Source: Darwin Volcanic Ash Advisory Centre (VAAC)

KVERT reported that during 23-24 and 28 July seismic activity from Karymsky was above background levels and suggested that possible ash plumes rose to an altitude of 2 km (6,700 ft) a.s.l. Seismic data were not available other days during 25-30 July due to technical problems. A daily thermal anomaly was detected in satellite imagery. Imagery also showed ash plumes that drifted 15 km SE on 26 July. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

KVERT reported that during 23-30 July seismic activity from Kliuchevskoi was above background levels and lava flowed down the SSE flank. Strombolian activity and gas-and-ash emissions were observed during 23-24 and 29 July. Cloud cover prevented observations the other days. Satellite imagery analysis showed a large daily thermal anomaly from the volcano and gas-and-ash plumes that drifted 145 km SW on 28 July. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

Observatory Vulcanológico and Sismológico de Manizales reported a seismic crisis at Cerro Machín on 24 July, characterized by volcano-tectonic earthquakes. One of the earthquakes was a M 2.6, located S of the main lava dome at a depth of 3.96 km. The next day a M 4.1 volcano-tectonic earthquake occurred 0.8 km S of the main dome at a depth of 3.88 km. On 29 July the number of volcano-tectonic events increased; the earthquakes were a maximum M 1.73 and between 3 and 4 km depth, S of the main dome. The Alert level remained at III (Yellow; "changes in the behavior of volcanic activity").

Source: Servicio Geológico Colombiano (SGC)

On 30 July INSIVUMEH reported that explosions from Pacaya's MacKenney cone were detected by the seismic network. Inclement weather prevented visual observations. During 2-3 August explosions produced ash plumes that rose 400-800 m above the crater and drifted S, causing fine ash to fall in areas 5 km away.

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

Based on a pilot observation, the Buenos Aires VAAC reported that on 28 July a gas plume from Planchón-Peteroa drifted E.

Source: Buenos Aires Volcanic Ash Advisory Center (VAAC)

KVERT reported that during 23-30 July seismic activity from Shiveluch was above background levels and a daily thermal anomaly was detected in satellite imagery. Possible ash plumes from hot avalanches and explosions on 28 and 29 July rose to altitudes of 4-6.5 km (13,100-21,300 ft) a.s.l. Gas-and-steam plumes were seen rising to an altitude of 4 km (13,100 ft) a.s.l. on 23 and 24 July. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

PHIVOLCS reported observations during the previous eight weeks after the Alert Level for Taal was raised to 2 (scale is 0-5, with 0 referring to No Alert status) on 8 June. Temperature measurements of the main crater lake did not increase further since 8 June, remaining between 330 and 340 degrees Celsius. The number of earthquakes recorded daily gradually declined to background levels beginning the second week of July. Hydrothermal activity in the N and NE sides of the main crater and Daang Kastila also decreased. Precise leveling measurements conducted during 13-21 July along the NE, SE, and SW flanks detected minimal inflation. On 2 August, PHIVOLCS lowered the Alert Level to 1.

Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS)

The IG reported that during 28 July-2 August steam emissions rose from Tungurahua's crater. On most days steam plumes with minor ash content rose 1-2 km above the crater and drifted NW or W. Minor ashfall was reported to the SW in the Choglontus area during 28-29 July.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)

RVO reported that white vapor plumes rose 300 m above Ulawun during 21-29 July. Light brownish ash clouds were observed on 23 and 24 July.

Source: Rabaul Volcano Observatory (RVO)