Solar activity was high due to a long duration M6 x-ray event at 0955 UTC. The event was associated with activity behind the southwest limb in cotemporaneous solar image data. A faint CME could be seen in LASCO images associated with the flare with an approximate plane-of-sky speed of 500 km/s. The CME does not appear to have any earthward component. The remainder of today's solar activity consisted of occasional C-class flares. With the departure of Regions 39, 44, and 50, Region 57 is now the dominant sunspot group on the disk. Region 57 has shown growth over the past 24 hours and possesses some magnetic complexity. The group produced occasional subflare activity.

Solar activity is expected to be mostly moderate over the next three days. There is a very slight chance, however, that one of the regions behind west limb could produce another major flare or proton producing event. Of the regions on the disk, Region 57 shows the best potential for producing an M-class event.

The geomagnetic field ranged from quiet to minor storm levels. A period of moderately negative Bz in the solar wind occurred from about 2300-0300 UTC and led to active to minor storm conditions from 0000-0900 UTC. The source of the enhanced Bz is uncertain, but may be related to a solar sector boundary crossing from towards orientation to an away orientation which occurred during the past 24 hours.

The geomagnetic field is expected to be mostly unsettled for the next three days. There is a possibility, however, for some isolated active periods on the third and fourth days as a coronal hole will be rotating into favorable position at that time.

  觀測的       04 Aug 151
  預測的   05 Aug-07 Aug  150/145/145
  90天平均值        04 Aug 167

  觀測的 Afr/Ap 03 Aug  011/020
  估算值     Afr/Ap 04 Aug  015/015
  預測的    Afr/Ap 05 Aug-07 Aug  010/010-010/010-012/015