Solar activity was at low levels. Low-level C-class events were observed from Region 1401 (N16W53) and Region 1402 (N29W48). Region 1401 indicated slight decay while Region 1402 showed some growth in the trailer spots.

Solar activity is expected to be low during the period (25 - 27 January) with M-class activity likely from Regions 1401 and 1402.

The geomagnetic field was at quiet to active levels with isolated minor to major storm periods. At 24/1431Z, an interplanetary shock passage was recorded at the ACE satellite with a corresponding sudden impulse of 22 nT observed at the Boulder magnetometer at 24/1504Z. At the time of the IP shock passage, Bt reached a maximum of 37 nT at 24/1439Z while the Bz component of the interplanetary magnetic field hit a maximum northward extent of 27 nT at 24/1436Z and a maximum southward extent of -16 nT at 24/1807Z. Wind velocity, as measured at the SOHO spacecraft, were observed at shock passage near 750 km/s with post shock passage speeds near 650 km/s. The greater than 100 MeV proton flux event that began at 23/0445Z, reached a maximum of 2 pfu at 23/0750Z and ended at 23/2050Z. The greater than 10 MeV proton flux event that began at 23/0530Z, reached a new maximum of 6310 pfu at 24/1530Z and was still in progress at the time of this writing.

The geomagnetic field is expected to be at unsettled to minor storm levels, with isolated major storm intervals, on day one (25 January) as effects from the arrival of the 23 January CME persist. By day two (26 January), the field is expected to be at mostly quiet levels as CME effects wane. Quiet to unsettled levels, with isolated active periods, are expected on day three (27 January) due to a recurrent coronal hole high speed stream rotating into a geoeffective position. The greater than 10 MeV proton flux event is expected to remain above threshold through 26 January, falling to background levels by 27 January.

  Observé       24 Jan 136
  Prévisionnel   25 Jan-27 Jan  140/140/135
  Moyenne des 90 derniers jours        24 Jan 143

  Observé Afr/Ap 23 Jan  007/011
  Estimé     Afr/Ap 24 Jan  022/030
  Prévisionnel    Afr/Ap 25 Jan-27 Jan  018/020-005/005-007/008