A CME launched from sunspot AR2014 on March 23rd is expected to deliver a glancing blow to Earth's magnetic field on March 25th. NOAA forecasters estimate a 30%-40% chance of polar geomagnetic storms on March 25-26.
On March 23rd around 0330 UT, the magnetic canopy of sunspot AR2014 became unstable and erupted, producing a long-duration C-class solar flare. Although C-class flares are considered to be minor, this one lasted so long (several hours) that it unleashed the energy-equivalent of a much stronger flare.
Depending on where the impact of the CME blast will reach on Earth, it is common for that area to experience temporary radio black- outs and possible satellite disruptions. There is also some evidence that earthquakes can be triggered by the geomagnetic storms caused by the CME (Coronal Mass Ejection) wave when it hits the Earth's crust.