Solar wind summary

The solar wind field at the ACE spacecraft was relatively unchanged
until about 28/0400 UTC. Wind speed had lingered around 280 km/s and
Phi had been positive (away). Between 28/0400-0549 UTC, wind speed rose
to 363 km/s and Bz approached -6 nT. Bt reached about 7 nT. Phi
briefly shifted to a negative (toward) orientation before becoming
positive around 28/0900 UTC. After 28/0549 UTC, wind speed abruptly
returned to around 270 km/s where it has remained. The low energy
particle flux at ACE continued to rise, suggesting the impending arrival
of the expected transient. Additionally, the greater than 10 MeV
particle flux recorded by the ACe/SIS instrument began rising after the
X1 event mentioned earlier and had reached 3.8 pfu by 28/1030 UTC.

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