Solar activity increased to high levels. Region 44 (S22E03) produced two major flares early in the period: an M8/2n at 26/2112 UTC and an M5 at 26/2217 UTC, both associated with moderate to strong discrete radio bursts. The M8 flare was also associated with a full-halo CME. Both major flares occurred along the magnetic neutral line separating Regions 44 and 39 (S16E07). Some decay was observed in the leader spots of Region 44, but it remained large and magnetically complex with a magnetic delta configuration evident within its intermediate spots. Region 39 produced isolated C-class flares including a C9/Sf at 27/0212 UTC. It also remained large and complex, but changed little during the period. Strong magnetic delta configurations persisted within its leading and trailing spots. Region 45 (N06W25) was in a growth phase and displayed minor polarity mixing. New Region 51 (S17E65) was assigned.

Solar activity is expected to be at moderate to high levels. Isolated M-class flares are expected from Regions 39 and 44. There is also a fair chance for a major flare from either of these regions.

Geomagnetic field activity was at unsettled to active levels during most of the period. This activity may have been due to a weak high-speed solar wind stream. The greater than 10 MeV proton event that began at 22/0655 UTC ended at 27/0320 UTC. The maximum flux for this event was 28 pfu at 23/1025 UTC.

Geomagnetic field activity is expected to be at unsettled levels at the start of the period. Activity is expected to increase to active to major storm levels beginning late on 28 July as today's halo CME reaches Earth. This disturbance is expected to subside to mostly unsettled levels by 30 July. There is a chance for a greater than 10 MeV proton event during the period.

  觀測的       27 Jul 231
  預測的   28 Jul-30 Jul  230/225/220
  90天平均值        27 Jul 164

  觀測的 Afr/Ap 26 Jul  010/017
  估算值     Afr/Ap 27 Jul  013/017
  預測的    Afr/Ap 28 Jul-30 Jul  010/012-025/030-018/020