17 December

Solar wind parameters, measured at ACE, reflected the continued decline
of effects from a waning coronal hole high speed stream (CH HSS). Solar
wind speed began the period near 440 km/s with occasional speeds as high
as 458 km/s. They then steadily decreased to end the period just under
380 km/s. The total field strength values ranged from 2 nT to 4 nT while
the Bz component fluctuated between +3 nT to -4 nT. The phi angle has
remained in a negative (away) orientation for the past 24 hours.

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