Solar activity was at moderate levels. Region 9973 (S16E48) produced the largest flare of the period, an M1/Sf occurred at 30/1725 UTC. This region also produced several minor subflares, some of which were associated with Type III radio sweep activity. Also, it may have been responsible for several optically uncorrelated C-class flares. It underwent a very slight decay, but retained a gamma magnetic configuration within its trailer spots. Old Region 9957 produced the first M1 x-ray flare today at 30/0532 UTC. The associated partial halo CME seen on LASCO imagery does not appear as though it will be geoeffective. Region 9963 (N16W56) produced a lone C1/Sf flare during the period. This region underwent some decay today, although it retains a weak gamma magnetic classification in its lead cluster of spots. New Region 9976 (S10E01) was numbered today.

Solar activity is expected to be at moderate levels. Region 9973 has a slight chance of producing a major event.

The geomagnetic field was at quiet to unsettled levels. The Advanced Composition Explorer (ACE) satellite hinted that a weak shock passage occurred at approximately 30/0030 UTC, with unsettled conditions following. This was believed to be from the disappearing filament on 27 May.

The geomagnetic field is expected to be at quiet to unsettled levels. Isolated active conditions may be possible through day one of the forecast period.

  觀測的       30 May 180
  預測的   31 May-02 Jun  180/175/170
  90天平均值        30 May 182

  觀測的 Afr/Ap 29 May  006/012
  估算值     Afr/Ap 30 May  010/012
  預測的    Afr/Ap 31 May-02 Jun  008/010-005/010-005/008