Solar activity has been high. Region 1598 (S12E44) produced an X1 event with an associated Tenflare and Type-II radio sweep at 23/0317Z. There was no CME observed in association with this event. Region 1598 remains the most threatening region on the disk and appears to have a Delta magnetic configuration within its trailer spots. Region 1596 (N07E06) is also moderately sized and has some magnetic complexity, but did not produce any flares during the period. Region 1593 (N15W33) produced a long-duration C3 event at 23/0821Z with an associated CME seen on STEREO-A imagery. There is not enough data available to model the CME, but at this time it does not appear likely to be geoeffective. Newly numbered Region 1599 (S09E73) appears to have a simple alpha magnetic class. The other regions on the disk either remained stable or were decaying.

Solar activity is expected to be moderate to high with occasional M-class events, and a slight chance for an isolated X-class event for the next three days (24 - 26 Oct) with Region 1598 the most likely source.

The geomagnetic field was quiet for the past 24 hours. Solar wind speed, as measured at the ACE spacecraft, remained steady throughout the period at approximately 370 km/s. The Bz component of the interplanetary magnetic field ranged from +/- 4 nT and the Phi angle changed to a positive sector at 22/2300Z. These signatures are consistent with a solar sector boundary crossing. The greater than 2 MeV electron flux at geosynchronous orbit was at high levels throughout the period.

The geomagnetic field is expected to be quiet for the next three days (24 - 26 Oct).

  觀測的       23 Oct 142
  預測的   24 Oct-26 Oct  140/140/140
  90天平均值        23 Oct 121

  觀測的 Afr/Ap 22 Oct  002/002
  估算值     Afr/Ap 23 Oct  007/007
  預測的    Afr/Ap 24 Oct-26 Oct  006/005-006/005-006/005