Solar activity has been moderate. Region 1283 (N17W55) produced two M-class flares. The first was an M2/1n at 09/0611Z with an associated Type II radio sweep (estimated velocity 717 km/sec) and a non-geoeffective CME. The second was an M1/1f at 09/1249Z. Region 1283 showed penumbral and trailer spot decay. Region 1289 (N22E37) developed a trailer spot with penumbra. New Region 1290 (S15E29) was numbered during the period.

Solar activity is expected to be moderate during the period (10 - 12 September) with a slight chance for another X-class flare from Region 1283.

Geomagnetic field activity began the period at quiet levels then increased to active to major storm levels after 09/1245Z. An isolated severe storm period was observed from 09/1500 - 1800Z. Two sudden impulses (SI) were observed at 09/1243Z and 09/1250Z (16nT and 28nT respectively, as measured by the Boulder USGS magnetometer). At 09/1150Z, ACE data indicated an interplanetary shock arrival preceding the Boulder SIs. Bt reached up to 25nT, Bz dropped to -23nT, density spiked up to 35p/cc, wind speeds peaked at 602km/s, and temperature increased. Activity was due to combined CMEs associated with 06 - 07 September major flare activity. The greater than 2 MeV electron flux at geosynchronous orbit reached high levels during the period.

The geomagnetic field is expected to be active on day 1 (10 September) due to continuing CME effects. Activity is expected to decrease on day 2 (11 September) to unsettled levels with a chance for active periods as CME effects subside, but a recurrent coronal hole high speed stream (CH HSS) will become geoeffective. Day 3 (12 September) unsettled activity is expected to continue under the effects of the CH HSS. There will be a slight chance for a greater than 10 MeV proton event at geosynchronous orbit during the period.

  Observed       09 Sep 112
  Predicted   10 Sep-12 Sep  110/110/110
  90 Day Mean        09 Sep 099

  Observed Afr/Ap 08 Sep  002/004
  Estimated     Afr/Ap 09 Sep  018/035
  Predicted    Afr/Ap 10 Sep-12 Sep  020/022-012/015-008/008