Solar activity was moderate. Region 9433 (N18W39) produced an M1/1f flare at 27/1915 UTC along with isolated C-class subflares. Region 9433 began to gradually decay following yesterday's M7/2b flare with decreased spot count and penumbral coverage. However, a magnetic delta configuration persisted in the trailer portion of the region, where most flare activity has occurred. Region 9441 (N08E38) produced isolated subflares as it gradually increased in spot count and penumbral coverage, though it remained a moderate-sized, simply-structured spot group. New Region 9443 (S10E21), a small simple bipole, was numbered.

Activity is expected to be at moderate to high levels. Region 9433 is expected to produce mostly low-level M-class flares. However, it may produce an isolated major flare during the period.

Geomagnetic field activity was at quiet to unsettled levels. The greater than 10 MeV electron flux became enhanced following yesterdays M7/2b flare, but did not reach event levels.

A geomagnetic disturbance is expected to commence during the latter half of 28 April and continue into 29 April following yesterday's M7/2b flare and associated full-halo CME . Active to major storm levels will be possible during this disturbance. Mostly unsettled levels are expected during 30 April. The greater than 10 MeV proton flux could increase to event levels on 28 April. Region 9433 may produce a proton flare during the period.

  觀測的       27 Apr 191
  預測的   28 Apr-30 Apr  185/180/175
  90天平均值        27 Apr 167

  觀測的 Afr/Ap 26 Apr  008/007
  估算值     Afr/Ap 27 Apr  005/008
  預測的    Afr/Ap 28 Apr-30 Apr  015/010-040/040-012/020