Magnetic Storm (source: link)

A magnetic storm is a disturbance in the Earth's magnetic field caused by coronal mass ejections (CMEs) or solar flares from the Sun. It usually begins between 24 and 36 hours after the solar event, when a shock wave of solar wind reaches the Earth's ionosphere. The storm then typically lasts 24 to 48 hours, though some may last as long as days. The effects of such a storm include disruption of communications and navigation systems, intense auroras, damage to satellites, and during the most extreme storms, induced currents in power lines and pipelines that result in power outages and corrosion.

Serious magnetic storms occur once every decade or so, with the most severe occurring once every century. They occur when energetic particles from a solar storm collide with the ionosphere and magnetosphere, creating a cascade of energetic particles and disturbing the atmosphere's magnetic and electric currents. There have been two severe magnetic storms in the last two centuries, including a storm on 28 August - 2 September 1859, which is the largest on record, and another on 13 March 1989.