The Sun produced several C-class flares and one isolated M-class flare. The C-class flares mainly originated from NOAA AR 2149.
A partial halo CME was visible in SOHO/LASCO C2 imagery with first measurement on August 24 at 12:36 UT. The CME was also visible in Stereo B/COR2 images from 13:24 UT onwards. The CME is associated with a M6 flare peaking at 12:17 UT and a type II radio burst (shock speed estimated at 593
km/s by the San Vito station). NOAA AR 2151 is identified to be source region.
The CME is propagating in the eastern direction from the Sun-Earth line with a projected line-of-sight speed of 473 km/s (CACTus estimate). Due to the position of the source region, the CME is not expected to have an Earth-directed component.
Two filament eruptions occurred; one centered at S30E35 on August 24 at 13:29 UT and one centered at N15W15 lifting off on August 25 at 7:09 UT. No associated CMEs were identified so far. Flaring activity is expected to continue with C-class flares and potentially an M-class flare.
Solar wind speed has decreased till 260 km/s currently. The amplitude of the interplanetary magnetic field ranged from 0 to 6 nT, with a varying Bz component. The phi angle was mostly negative (toward), but changed to positive (away) at 11:00 UT. Geomagnetic conditions were quiet to unsettled and are expected to remain so until the combined arrival of the August 22 CME’s. This may potentially result in active geomagnetic conditions from the afternoon of August 26 onwards.
SIDC