The sun. Hold on to your hats! NOAA Space Weather Advisory said today:

"Extreme geomagnetic storms could cause problems with power systems, spacecraft operations and other high and low frequency systems like satellite navigation and communications," said Bill Murtagh, a space weather forecaster at the NOAA Space Environment Center. Aviation groups have reported moderate to severe impacts to operations over the past two days due to degraded communications."

"Although NOAA predicted a major storm, this storm was unusually strong," added Murtagh. "The coupling between the solar wind interplanetary magnetic field and Earth's magnetic field was very strong. In fact, we've only observed this intense level of coupling a handful of times over the past 10 years."

Lots of flooding, earthquakes, and disturbances today! I note patterns as the Chief Editor of the Earthchanges TV Breaking News sections. There has been a huge spike in unusual earth/weather activity in the last couple days.