This is a flare, not a CME (yet). The Carrington Event of 1859 is estimated to have been a flare of around class X50. Yes, fifty. In 2003, we had an X45, damaged a few sats and caused a one-hour power outage in Sweden. Flares may be related to the launching of CME's, which are what causes the real effects on Earth. The Carrington Event lasted for days, which made it a global event, unlike a nuclear-induced EMP, which is almost instantaneous and pretty localized.
So when we get an X40+ flare and then a CME, I'll worry. Good thing is that we know approximately when a CME will arrive, and we usually have a day or two to prepare.