Solar activity was moderate. Region 540 (S14E02) produced an M1/1n flare at 18/0017Z. Moderate to strong radio bursts accompanied this flare including a 190 sfu Tenflare and a large 23,000 sfu burst on 245 MHz. A Type II radio sweep was also observed with a shock speed of near 1000 km/s. This beta-gamma spot group has not changed much over the past 48 hours, although some new growth was noted in the trailer spots. Region 537 (N04W83) was quite active this period as it approached the west limb. It produced occasional C-class activity including a C3 flare and CME at 18/2003Z. Remaining regions were stable.

Solar activity is expected to be low to moderate. Moderately complex Region 540 has potential for isolated M-class flares. Further C-class activity is expected from Region 537 on the west limb.

The geomagnetic field was quiet to active. A coronal hole high speed stream continues with solar wind speed ranging from 520 to 620 km/s. The IMF Bz was predominantly northward; however, periods of southward Bz occurred inciting the occasional active periods. The greater than 2 MeV electron flux at geosynchronous orbit reached high levels again today.

The geomagnetic field is expected to range from quiet to minor storming over the next three days. The high speed solar wind stream in progress now is expected to persist through 19 January and produce occasional active periods. The M5 flare that occurred on 17 January did produce a CME, but LASCO imagery shows that most of the ejecta is southward directed. Some weak impacts are expected on 20 January from this CME, but the disturbance should be limited to occasional active periods with isolated high latitude minor storming. Quiet to unsettled levels are expected on 21 January with isolated active periods possible.

  觀測的       18 Jan 120
  預測的   19 Jan-21 Jan  120/115/115
  90天平均值        18 Jan 138

  觀測的 Afr/Ap 17 Jan  009/014
  估算值     Afr/Ap 18 Jan  012/016
  預測的    Afr/Ap 19 Jan-21 Jan  010/012-015/025-012/015