Solar wind summary (Last 24 hours)

17th October

The solar wind environment at the ACE spacecraft was nominal. Wind
speed remained in the low to mid 400 km/s range. Phi was negative, Bt
was at or below 7 nT and Bz never dipped below -6 nT.

16th October

Solar wind speed at the ACE spacecraft remained in the low to mid 400
km/s range. Phi was negative; Bz never dipped below -5 nT while Bt
never rose above 8 nT.

15th October

The solar wind environment remained disturbed for the first half of the
period in response to a glancing blow passage of a CME observed on 10
October, possible mixed with effects from a coronal hole high speed
solar wind stream. Bt reached 16 nT while Bz dipped as low as -12 nT
between 14/1200-15/0000 UTC, fluctuating between periods of northward
and southward orientation. After 00Z, Bt began to decrease and Bz
became predominantly positive. Solar wind speed was initially between
400-450 km/s and increased to a maximum of 580 km/s at 15/0040 UTC.
This increase was coincident with a modest rise in temperature and a
primarily negative Phi orientation.

14th October

Solar wind conditions at the ACE spacecraft suggested tine influence of
a modest coronal hole high speed stream which became geoeffective early
in the period yesterday. Solar wind speed increased from around 350
km/s to the low 400 km/s range. Temperature increased slightly as well.
The solar sector remained negative while Bt climbed to 12 nT by 14/0950
UTC and Bz dipped as low as -6 nT early in the period, but was
predominantly positive after 13/2143 UTC.

13th October

Solar wind conditions depicted nominal conditions throughout the period.
Solar wind varied between a low of near 300 km/s to a high of about 340
km/s. Total field (Bt) measurements varied between 3-9 nT while the Bz
component did not vary much beyond +5 to -2 nT. Phi measurements
indicated a negative (towards) solar sector orientation through about
13/0930 UTC when the phi angle rotated to a more positive (away) sector.

12th October

Solar wind conditions were fairly nominal during the period. Total field
(Bt) measurements ranged from an early high of 8 nT and gradually
decreased to a reading of about 4 nT late in the period. IMF Bz was
mostly positive while solar wind speeds were stable between 325-360
km/s. Phi measurements indicated a solar sector boundary (SSB) crossing
from a positive (away) sector to a negative (towards) sector at 11/1118
UTC and remained in a negative orientation through the summary period.

11th October

Solar wind conditions displayed a return to largely nominal conditions.
Slight agitation was observed due to night-time extended periods of
negative Bz. Bt gradually increased from around 6nT to end the period at
about 9nT. The Bz component was predominately negative between -5nT to
-7 nT. The Phi angle was in a predominately positive (away) sector.
Solar wind speeds averaged 350 km/s through the period.

10th October

Solar wind conditions displayed continued disturbed conditions following
a solar sector phi change from negative (towards) to positive (away)
early on 08 October. Bt remained slightly enhanced near 10 nT while the
Bz component was variable, reaching southward deviations at times to -7
nT. Solar wind speeds indicated a slight decrease from about 360 km/s to
near 330 km/s.

9th October

Solar wind conditions displayed continued agitation following a solar
sector change to a positive phi orientation change yesterday. Bt
remained slightly enhanced near 8nT. Bz displaced frequently over the
period to between -5nT and -8nT. Solar wind speeds remained steady near
350 km/s over the period.

8th October

Solar wind conditions were largely nominal for most of the period until
a solar sector change to a positive phi orientation change completed at
around 08/0600 UTC. Shortly after, Bt increased from an average between
4nT and 5nT to steady near 9nT. Bz displaced to -8nT, where it remains.
No SWEPAM signatures were noted. Solar wind speeds remained steady near
360 km/s over the period.