Message #19809

[martinastro]

Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels all three days of the forecast period (06 - 08 January). Isolated active to minor storm periods are possible beginning on 08 January. The forecasted increase in activity levels is due to a recurrent coronal hole high speed stream that is expected to rotate into a geoeffective position by 06 January.

Minor update added at 20:45 UTC: A high speed stream from CH431 is in progress. Solar wind density reached very high levels at ACE and peaked around 20h UTC. The interplanetary magnetic field has swung strongly southwards. Minor and even major geomagnetic storming is possible for the remainder of the day and early on January 7. The disturbance appears to be much stronger than anticipated.