CHANCE OF MAGNETIC STORMS: NOAA forecasters say there is a 55% chance of G1-class geomagnetic storms today as Earth moves through the wake of a passing CME. Boosting the odds of geomagnetic activity is an incoming stream of solar wind. Estimated time of arrival: Feb. 16-17. Arctic sky watchers should remain alert for auroras. Free: Aurora Alerts 

CME IMPACT SPARKS POLAR AURORAS: Yesterday, a CME struck Earth's magnetic field. "Right from the minute it got dark, our skies were alive with dancing aurora," reports tour guide Marianne Bergli of Tromsø, Norway. This is one of dozens of pictures she took between sunset and 3:30 the next morning:

"What an amaz​i​n​g​ night,' she says. "The CME arrived as predicted by Spaceweather.com, and something tells me there​ i​s much more to come."

Indeed, there is more. A stream of high-speed solar wind flowing from a wide hole in the sun's atmosphere is following close on the heels of the CME. It could produce a new round of geomagnetic activity and polar auroras when it arrives on Feb. 16th or 17th. Free: Aurora Alerts 

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