Solar activity was high. Region 486 (S17W09) has produced another major flare, an X10 flare at 29/2049Z. This very large flare was still in progress at the end of the period. Associated activity and the potential impact of this flare will be assessed during the next period. Region 486 also produced an M3 at 29/0511Z. This region with 2600 millionths of white light areal coverage is now the largest sunspot group of solar cycle 23. It maintains a strong and complex beta-gamma-delta configuration and is still growing. Region 488 (N08W18) is also a large, complex active region and now exceeds 1200 millionths in a beta-gamma-delta configuration. C-class activity and low M-class flares were observed in this region. The very large and active Region 484 (N01W81) is relatively quiet as it rotates around the west limb.

Solar activity is expected to continue at high levels. The very large and complex Region 486 will likely produce more major flare activity during its remaining 5-6 days on the visible disk. A major event is also possible from Region 488.

The geomagnetic field ranged from unsettled to severe storming. The powerful CME from the X17/4b flare on 28/1110Z, impacted the Earth's magnetic field at 29/0613Z. The transit time for this CME was around 19 hours, making it one of the fastest on record. The sudden impulse measured 140 nT on the Boulder magnetometer. Strong southward IMF Bz initiated severe (K9) storming at middle and high latitudes in the 29/0600 - 0900Z period. Mostly northward Bz occurred from 29/0900 - 1800Z; however, major to severe storming persisted. A sharp southward turn in the Bz occurred at around 1800Z ending the period with K8-9 severe storming. A strong Forbush decrease (over 20%) is in progress. The large proton event and GLE that followed the X17 flare is now in decline. The greater than 10 MeV proton event that began on 28/1215Z, peaked at 29/0615Z at 29,500 pfu, making it the second largest greater than 10 MeV proton event this cycle (second only to the 31,700 pfu proton event in November 2001). The greater than 100 MeV proton event began at 28/1145Z, and peaked at 29/0015Z at 186 pfu. This proton event remains in progress.

The geomagnetic field is expected to continue at severe storm levels through day one. The IMF Bz is now sustained southward at near -30 nT, resulting in severe storm levels. This condition is expected to persist through at least the first half of day one. A gradual decline to unsettled to minor storm levels is expected by day two. The potential geomagnetic impact from today's X10 flare will be assessed next period; predictions for days two and three will likely change considerably. The greater than 10 MeV proton event, currently in progress is expected to continue through day three. The greater than 100 MeV proton event will likely continue as high energy protons quickly stream in from the X10 flare that occurred late in the period.

  Observé       29 Oct 279
  Prévisionnel   30 Oct-01 Nov  275/265/260
  Moyenne des 90 derniers jours        29 Oct 126

  Observé Afr/Ap 28 Oct  015/020
  Estimé     Afr/Ap 29 Oct  120/150
  Prévisionnel    Afr/Ap 30 Oct-01 Nov  080/100-020/025-010/010