Solstice Geomagnetic Storm

Source - Space Weather News for Dec. 21, 2016: http://spaceweather.com

SOLSTICE GEOMAGNETIC STORM: Around the Arctic Circle, the longest night of the year has arrived with perfect timing. A high-speed stream of solar wind hit Earth's magnetic field on Dec. 21st (the northern winter solstice) filling the long hours of darkness with Northern Lights. At the time of this alert, a moderately strong G2-class geomagnetic storm is underway, and more storms are in the offing. Flowing from a huge hole in the sun's atmosphere, this solar wind stream is broad. Earth could take days to cross it.

Check Spaceweather.com for updates.