M4.5 Coronal Mass Ejection impact caused a G1 geomagnetic storm

Friday, 12 September 2014 05:08 UTC

The M4.5 CME has arrived right on time and the impact had clear glancing blow signatures with the IMF not responding all too much but a few stints of southward directed IMF still managed to get us up to minor G1 geomagnetic storming conditions. Auroral displays have already been reported near the US-Canadian border. The direction of the IMF is now mostly north but still hovering around the zero-line a bit. The solar wind speed and density remain elevated. Sky watchers around the US-Canadian border and Tasmania/south New Zealand should remain alert for aurora on the horizon.

The impact was detected by our automated CME alert system and those who follow us on Twitter or recieve our email alerts would have been alerted as soon as the CME arrived at the ACE satellite. Be sure to follow us on @_spaceweather_.

Weak #CME impact - Speed 433.4km/sec - IMF Bt (strength): 12.6nT. - Follow live on http://t.co/Gj5cI2OO1z pic.twitter.com/9SpfunFUD6

— SpaceWeatherLive (@_SpaceWeather_) 11 september 2014

X1.6 Coronal Mass Ejection
A Middle Latitude Auroral Activity Watch remains in place for today and tomorrow as the X1.6 Coronal Mass Ejection (CME) has yet to arrive. This CME was a full halo CME that was pretty much directly at Earth. It is scheduled to arrive today around 15:00 UTC with a plus/minus of 6 hours and solar wind speeds over 700km/s are possible. With the current geomagnetic instability in mind it is very much possible that X1 CME could push us up all the way to strong G3 geomagnetic storming tonight and perhaps also tomorrow which would mean good conditions for auroral displays on middle latitude locations. The low energy protons at ACE remain well above background level and a new sharp increase in the low energy protons could signal the arrival of the X1.6 CME. Be alert in the coming hours. Below you can find the real-time ACE EPAM plot that you will also find on our website:



Links worth reading: Help: Low, Middle and High Latitude and Help: How do we know if a CME is earth directed and when it's going to arrive?