"The larger of the two coronal mass ejections (CME) will hit sometime between late Friday morning and mid-day. The first CME arrived Thursday night.
These storms may cause radio communications problems and GPS signal degradation as well as lead to some voltage irregularities in the power grids in the northern latitudes of the U.S.
But the problems "are expected to be manageable and not cause any major disruptions to power transmission," said Thomas Berger, director of the U.S. Space Weather Prediction Center. "
http://www.computerworld.com/article/2643093/strong-solar-storm-set-to-arrive-wont-fry-electronics.html