According to spaceweather.com it was a CME arrival:
WEAK IMPACT: A coronal mass ejection (CME) struck Earth's magnetosphere at 0850 UT on Oct. 25th, but the impact did not trigger substantial geomagnetic activity. Soon after the CME swept past our planet, the interplanetary magnetic field near Earth tilted north -- a condition that often suppresses auroras.
The cloud that (ineffectually) buffeted Earth's magnetosphere today left the Sun on Oct. 22nd when twisted magnetic fields above sunspot 9672 erupted -- sparking two solar flares (categories M7 and X1) and hurling a pair of CMEs toward Earth. The expanding clouds likely merged en route and arrived today as a single shock wave.

And there was another X Flare:
An X1-class solar flare erupted today at 1500 UT from the vicinity of sunspot 9672. The blast triggered a strong (R3-class) radio blackout across the Americas and western Europe.

Canie

• SpaceWeather.com