Three Coronal Mass Ejections (CMEs) produced on June 18, 19 and 21 have now all arrived at our planet and their combined effects caused G4-Strong geomagnetic storm on 22nd June 2015.
Two of the three CMEs were produced by Region 2371, one of the biggest regions of the current solar cycle, which is currently directly facing Earth. This region has ‘beta-gamma-delta’ magnetic configuration and is capable of producing more strong to major eruptions on Sun. Due to its location, CMEs this region could produce over the coming days would most likely be Earth-directed.
Full-halo CME produced by a long duration M3.0 solar flare which erupted at 17:35 UTC on June 18 hit our planet at 16:50 UTC on 21st June. It was a glancing blow followed by the arrival of partial-halo CME (produced by filament eruption in the SSE quadrant early June 19) at 05:45 UTC on 22nd June.
Direct hit by full-halo CME produced early 21st June was registered at 18:37 UTC.
Geomagnetic K-index of 8 (G4-Severe) threshold was reached at 18:52 UTC.
Area of impact is primarily poleward of 45 degrees Geomagnetic Latitude.Under G4-Severe conditions, widespread voltage control problems are possible and some protective systems may mistakenly trip out key assets from the power grid. Induced pipeline currents intensify.
See You Tube video of CME click here https://www.youtube.com/watch?v=X9dzD2BRIM8