Northern Lights Now – The expected G1/G2 storming from the coronal hole pointed towards Earth on Sept 11 arrived late on Sept 13. It induced a period of fast solar wind, strong Bt and G2 storming. The timing was good for our aurora hunting followers in Northern Europe who had clear skies.
At the onset of the storm, Bz was strongly (-15 to -18 nT) south for over half an hour at the beginning of the storm, which set up Earth’s magnetosphere to be highly activated. This means that any additional strong wind, high density, or prolonged negative Bz can quickly jump the KP back into G1/G2 range.
Here are a couple Tweets share with NLN from tonight’s storming
From the Nidderdale in northern Yorks by @HudsonWeather
— Paul Taylor (@paultaylor85) September 14, 2017
From Christopher Suarez in Iceland
— Christophe Suarez (@suarezphoto) September 15, 2017
It is still possible that there could be additional storming. Keep your eyes on the Solar Wind Data. If there is a prolonged people (more than 45 mins or so) of negative Bz, there could be another round of storming.
Note: The current storm is likely the last for a while. There are now active regions that pose M or X class flare threats on the Sun and the next Coronal hole isn’t expected to reach Earth until late September. Make hay while the Sun shines!