Solar wind parameters were indicative of the arrival of an anticipated CME from 17 Feb. Total IMF strength was primarily 5-6 nT until the arrival of an interplanetary shock at the DSCOVR spacecraft at 20/0952 UTC. The IMF strength increased to 14 nT with shock arrival and eventually peaked at 16 nT. The IMF strength remained elevated from primarily 8-12 nT as the transient passage continued. The Bz component varied, and reached a maximum southward deviation of -7 nT, however, no prolonged periods of pronounced southward direction were observed. Solar wind speed abruptly increased from ~375 km/s to over 425 km/s with shock arrival and varied from mainly 425-475 km/s afterwards. The phi angle was predominantly in a positive sector. There is a 35% chance of solar activity, with a 30% chance of a minor event, a 5% chance of a moderate event, and a 1% chance of a strong event.
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