Pacific Summary Updated. 27 July 2025 - 11 August 2025
The period has unsurprisingly continued for a few days after the 27-28 July forecast was posted. The period actually began on 11 July with the onset of fast solar wind from a series of coronal holes, culminating in a massive Mag 7/8 quake period. The 27-28 July forecast captured the big Mag 6.9 series south of Macquarie Island, prompting a rare Mag 6 forecast for Fiordland. The forecast speculated that Kamchatka quakes might migrate to the Rat Islands but in the end they stayed in Kamchatka. The 28 July Sea of Okhotsk 4.3 400km deep quake was a potential precursor quake for Kamchatka to further unzip southwards from the Mag 7 series. The Kamchatka 8.8 was the final quake in the 14-30 July series which included Mag 7.4, 7.3, 8.8. The eruption of Kamchatka Peninsula volcano Kliuchevskoi in the same moment as the Mag 8.8 was dismissed as coincidental but the eruption of nearby Krasheninnikov on 3 August for the first time since 1550 left the experts stranded. A big eruption at Lewotobi was matched by smaller eruptions and/or tremor at many volcanos, including degassing, seismic swarms and increasing volcanic tremor at Ruapehu. The forecast rule that eruptions follow quakes was easily shown in this period. The same coronal hole that drove the action from the beginning of the period on 11 July has now rotated around with the Sun and about to link in behind a minor Kp6 filament period. A new forecast is being processed for 11 July. 27 July. 300km South of Macquarie Island 6.2 4.15am 28 July. Bardarbunga, Iceland 5.1 11.40am 29 July. Northwest of Sumatra 6.5 6.41am 300km South of Macquarie Island 6.9 10.10am 30 July. South of Fiji 5.8 5.46am 553km South of Fiji 6.6 5.53am 553km Kamchatka 8.8 11.24am Eruption Kliukchevskoi 11.24am approx. 3 August. Eruption Lewotobi, Kirishima, Sakurajima, Krasheninnikov, Kliuchevskoi. 5 August. Eruption Telica Forecast Summary. 30 July 12.00am This forecast only covered the final few days of a period beginning way back on 11 July and the arrival of fast solar wind from Coronal Hole 1306. No forecast was offered for the initial 16 days. Forecast uncertainties with the arrival of spaceweather on 15 July delayed a quake forecast, followed by a long period when the service was offline. The period turned into a twin Mag 7 and a Mag 6.9 quake period as conditions shifted away from volcanos in June and early July to quakes from mid July. Frustratingly a detailed forecast wasn't posted until 27 July and the period nearly ended. A Facebook post on 13 July gave some casual spaceweather and quake location clues. Macquarie Island has become a good forecast location success over the wider period. Macquarie Island quakes are much less frequent than Kermadecs quakes because quakes are always more frequent nearer the Equator, less frequent at the Poles. Regardless of lower quake frequency, Mag 8 has been recorded at Macquarie Island in the past and the period was the first since this service began in 2012 where Macquarie Island quakes were frequent enough to make a detailed quake migration pattern study. The period has probably ended on 29 July as 18 days of fast solar wind finally drops to background levels of 400km/second. A separate summary will be posted for the earlier 11-26 July period. The 27-28 July forecast period came from a weak filament eruption arriving at ACE satellite on cue. Magnetic flux density remained positive until 28 July 1200UTC when it suddenly switched to -5nTesla and Mag 6 followed about 6 hours later under mild Kp4 geomagnetic driving conditions. 27 July. 300km South of Macquarie Island 6.2 4.15am 28 July. Bardarbunga, Iceland 5.1 11.40am 29 July. Northwest of Sumatra 6.5 6.41am 300km South of Macquarie Island 6.9 10.10am Forecast. 27-28 July 2025. Magnitude 6 risk locations are Macquarie Island, NW Snares Islands, Offshore Fiordland, Northern Tonga, Bismarck Sea, New Ireland, Molucca Sea, Rat Islands. Possibility Mag 7. Rat Islands, Macquarie Island higher risk. Aotearoa Earthquake and Volcano Forecast Service © 2013 - 2025 |
