:Product: Weekly Highlights and Forecasts
:Issued: 2003 Sep 09 2212 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Environment Center
# Product description and SEC contact on the Web
# http://www.sec.noaa.gov/weekly.html
#
#                Weekly Highlights and Forecasts
#
Highlights of Solar and Geomagnetic Activity
01 - 07 September 2003

Solar activity ranged from very low to low levels.   Activity was
very low on 01 – 03 September and again on 06 September while low
levels were observed on 04, 05, and 07 September.  The largest flare
of the period was a C5/Sf flare and filament eruption on 07
September at 1407 UTC from Region 450 (S16, L=301, class/area
Fso/120 on 03 September).  LASCO imagery indicates the CME
associated with this flare was off to the southwest. All of the
sunspot regions on the visible disk during the summary period were
relatively small and magnetically simple.  The only region to reach
a white light area of 200 millionths was region 453 (S23, L=323,
class/area Dso/200 on 06 September).

Solar wind data were available from the NASA Advanced Composition
Explorer (ACE) spacecraft for most of the summary period.  On 01
September, a co-rotating interaction region (CIR) was observed with
solar wind speeds increasing to 550 km/s.  The coronal hole high
speed flow that followed increased wind speeds to 700 km/s by 04
September.  Late on 04 September, wind speeds began a gradual
decline and by 06 September were down to 575 km/s.  By 07 September,
wind speeds were back down to 400 km/s.  The Bz component of the
interplanetary magnetic field reached –10 nT during the CIR but
remained above –5 nT during the majority of the coronal hole high
speed flow.

There were no greater than 10 MeV proton events at geosynchronous
orbit during the period.

The greater than 2 MeV electron flux at geosynchronous orbit reached
high levels on 02 September and again on 05 – 07 September.

Geomagnetic activity ranged from quiet to active levels.  On 01
September, the co-rotating interaction region produced quiet to
active conditions.  The coronal hole high speed flow that followed
produced mostly unsettled to active conditions on 02 – 05 September.
The period ended with quiet to unsettled activity on 06 – 07
September.

Forecast of Solar and Geomagnetic Activity
10 September - 06 October 2003

Solar activity is expected to range from very low to low levels
during the period.

No greater than 10 MeV proton events at geosynchronous orbit are
expected during the period.

The greater than 2 MeV electron flux at geosynchronous orbit is
expected to reach high levels on 10 – 11 September, 20 – 23
September and again on 02 – 05 October.

The geomagnetic field is expected to range from quiet to major storm
levels during the period.  Minor storm levels are possible on 10
September due to effects from the CME on 7 September.  A large
coronal hole high speed flow is expected to return on 17 – 20
September with major storm levels possible.  Another coronal hole is
due to return on 01 – 03 October and is expected to produce mostly
active conditions with isolated minor storm levels possible.