INFO FROM SIDC - RWC BELGIUM 2015 Mar 18 12:32:30
Solar flaring activity was moderate over the period with the largest flare an M1 flare from NOAA active region 2297 peaking at 23:31UT. The second largest flare of the period, a C9.3 flare peaking at 7:51UT was produced by a newly emerged region in the western hemisphere near N10W54, numbered NOAA 2302. Several additional C flares were produced by both regions. The region turning onto the visible disc on the eastern hemisphere was numbered NOAA 2303. Region 2297 continues to be the most complex region on disc although it decayed slightly. M flaring from this region remains likely.
The newly emerged region 2302 evolved significantly and adds to the M-flaring probability. A slight chance for an X flare also remains in addition to the likely M flaring activity. The M flare from region 2297 was associated with a type II radio burst and a coronal dimming. The corresponding CME appeared to be rather narrow and directed westward and is not expected to have any influence to Earth. A filament eruption occurred near disc centre (S10W05) between 9:54 and 10:09 UT. No Earth directed CMEs were recorded in coronagraph images. Solar wind conditions were dominated by the March 15 CME impact. After the passage of the shock front early yesterday solar wind speed continued to increase reaching a peak of over 650 km/s around 10:45 UT March 17 and afterwards declining to current values of around 560 km/s.
Total magnetic field reached a peak of over 35 nT around 13:35 UT afterwards declining to current values of around 11 nT. The Bz component was pronounced negative during the CME passage with values mostly hovering in the -15 to -20 nT range and with peaks down to -27 nT. Bz is currently roughly neutral. Temperature rose while density dropped during the event. Some rotation in phi angle was observed during the CME passage.
Severe geomagnetic storm conditions were recorded at planetary level (NOAA Kp reaching 8) with also locally strong geomagnetic storm conditions (K Dourbes 7). Currently geomagnetic conditions have settled down to between unsettled and minor storm conditions. Solar wind conditions are expected to show the further decline of the CME influence, although solar wind conditions could remain elevated for an extended period due to the possible influence of a negative coronal hole high speed stream. Geomagnetic conditions are expected to be at unsettled to active or even minor storm levels.