Last major update issued on May 27, 2012 at 05:45 UTC.
The geomagnetic field was quiet to unsettled on May 26. Solar wind speed at SOHO ranged between 347 and 460 km/s.
Solar flux measured at 20h UTC on 2.8 GHz was 110.0 (decreasing 6.0 over the last solar rotation). The Potsdam WDC planetary A index was 4 (STAR Ap - based on the mean of three hour interval ap indices: 4.3). Three hour interval K indices: 31111000 (planetary), 21121211 (Boulder).
Region 11486 [N17W38] was quiet and stable.
Region 11488 [N11E02] was quiet and stable.
Region 11489 [S23E03] was quiet and stable.
Region 11490 [S12E32] added a few spots and has minor polarity intermixing.
Region 11491 [N23W42] was mostly quiet and stable.
Region 11492 [S14E60] produced a couple of minor C class events and has M class flare potential.
S1671 [S19W11] was quiet and stable.
S1682 [S22E62] was quiet and stable.
S1684 [N21E06] was quet and stable.
New region S1686 [S18E13] emerged with small spots.
New region S1687 [S28E18] emerged with tiny spots.
New region S1688 [N31W08] emerged with tiny spots in an old plage area.
New region S1689 [N17W65] emerged with a single spot.
New region S1690 [S07E47] emerged with reversed polarities.
New region S1691 [S26E40] emerged with a tiny spot.
The most significant event of the day occurred at 20:45 UTC in AR 11476 several days behind the west limb. This major event was associated with a full halo CME and a noticable increase in the above 10 MeV proton flux.
May 24-26: No obviously Earth directed CMEs were observed in LASCO or STEREO imagery.
The geomagnetic field is expected to be quiet to unsettled on May 27-28 due to possible weak effects from CH519 and quiet on May 28-29.