G2 (Moderate) Geomagnetic Storms Observed on 20 December
published: Sunday, December 20, 2015 22:55 UTC UTC
An enhanced solar wind environment and prolonged period of southward magnetic field, associated with the passage of a coronal mass ejection, has caused planetary G2 (Moderate) geomagnetic storms. G2 storm levels were first observed at 20/0519 UTC (0019 EDT) and G2 (Moderate) geomagnetic storm conditions are expected to persist until 1000 UTC (0500 EDT) on 20 December as this event continues.