A geomagnetic storm is currently in progress due to ongoing negative polarity coronal hole high speed stream (CH HSS) influence. The G1 Watch is in effect for the next three days.
Geomagnetic K-index of 5 (G1 - Minor geomagnetic storm) threshold was first reached at 20:50 UTC on December 9, 2016.
Total IMF strength and solar wind speed are expected to remain elevated through the remainder of December 9 under the continuing, early influences of the CH HSS. Total field strength is anticipated to weaken on December 10.
Solar wind speeds are likely to remain over 500 km/s as CH HSS influence continues. Elevated solar wind speeds are expected to continue into December 11, but are anticipated to begin weakening as CH HSS effects start waning.
As a result, mostly unsettled to active conditions are expected, with isolated G1 - Minor storming periods until December 11 when conditions are expected to decrease to quiet and unsettled levels, with isolated active periods.
Meanwhile, solar activity is at very low levels and is expected to remain like that over the next three days. There is a slight chance, although decreasing, for C-class flares on December 9 and 10 due to the continued decay and inactivity trend of Region 2615.
Featured image: Aurora forecast, model run 21:50 UTC, observation time 21:40 UTC, December 9, 2016. Credit: SWPC/NOAA