[jongaltsr]

Comments welcome....

[outofsalt]

The peak of the magnetic storm was 6/16 when one CME caught up to and combined with a slower moving CME. The storm's effects lasted a couple of days. On the link above you can look to the archived pages over the last few days. Here is an entry from the 17th.
“GEOMAGNETIC STORM ALERT: A geomagnetic storm is in progress in the wake of a double CME impact on June 16th. The hit, which strongly compressed Earth's magnetic field, lit up both poles with bright auroras. Stephen Voss sends this photo from Southland, New Zealand:”
JMHO as to a possible explanation.