Geomagnetic storms have picked up, says NASA's Alex Young, and a new solar flare occurred about 7:30 p.m. PST on Thursday.
The flare, Young says on his site, produced some temporary radio blackouts, and there could be more activity from the sunspot group where the flare originated.
At the current kp index level, according to the National Oceanic and Atmospheric Administration, high-frequency radio -- and thus some airline routes -- as well as power systems could be affected.
Solar storms this strong also could wreak havoc with satellite navigation and spacecraft components.
Meanwhile, those in northern climes were expecting some terrific auroras in Friday's early morning hours. Auroras were possible as far south in the U.S. as Illinois and Oregon, NOAA said.