:Product: Weekly Highlights and Forecasts
:Issued: 2002 Aug 27 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
19 - 25 August 2002

Solar activity was at high levels on 20 – 22 August and again on 24
August.   Region 69 (S08, L=299, class/area Ekc/1990, on 19 August)
produced an X3/1f on 24 August with an associated 1200 sfu Tenflare,
Type II and Type IV radio sweeps, and a full halo CME.  Region 69
produced the majority of activity throughout the period including
numerous M-class and C-class flare with strong radio components. 
For flare times and magnitudes, please refer to the Energetic Events
or Optical Flare lists.  Region 69 was a large and magnetically
complex spot group early in the period.  It entered a gradual decay
phase on 20 August and rotated beyond the west limb on 24 August. 
Other regions of interest were Region 83 (S19, L=231, class/area
Fao/170 on 23 August) and Region 87 (S07, L156, class/area Dki/410
on 25 August).  Region 83 produced a number of M-class events and
developed a beta-gamma magnetic configuration.  At the close of the
period Region 87 was a moderately sized spot group with a beta-gamma
magnetic configuration.

Solar wind data were available from the NASA Advanced Composition
Explorer (ACE) spacecraft for most of the summary period.  At the
beginning of the period solar wind velocity was elevated to around
550 km/s due to residual CME shock activity on 18 August.  Solar
wind velocities continued a steady decline until approximately 1700
UTC on 20 August when a small transient shock was observed. 
Following the transient the IMF entered an 18-hour period of
negative Bz.  Solar wind velocities were variable on 22 August then
continued a steady decline to near 300 km/s at the close of the
summary period.

Two proton events were observed this period.  The first occurred on
22 August from an M5/2b flare from Region 69.  The 10 MeV proton
event began at 22/0440 UTC, reached a peak value of 36 pfu at
22/0940 UTC and ended at 23/0040 UTC.  A 100 MeV proton event began
at 22/0340 UTC, reached a peak value of 1.7 pfu at 22/0510 UTC and
ended at 22/0615 UTC.  The second proton event was due to the X3/1f
flare on 24 August.  The 10 MeV proton event began at 24/0140 UTC,
reached a peak value of 317 pfu at 24/0835 UTC and was still in
progress at the close of the summary period.  A 100 MeV also began
at 24/0130 UTC, reached a peak value of 29 pfu at 24/0210 UTC, and
ended at 24/1825 UTC.

The greater than 2 MeV electron flux at geo-synchronous orbit was at
normal to moderate levels throughout the summary period.

The geomagnetic field was at quiet to severe storming levels.  Active
to minor storming conditions were prevalent on 19 August due to CME
shocks that arrived on 18 August.  Active to severe storming
conditions on 20-21 August were the result of the 18 hour period of
negative Bz mentioned above.  Geomagnetic activity was mostly quiet
to unsettled for the remainder of the summary period (22-25 August).

Forecast of Solar and Geomagnetic Activity
28 August - 23 September 2002

Solar activity is expected to be at low to moderate levels for most
of the forecast period.  There is a chance of high activity, with
the return of old Region 69, on 07-22 September.

There is also a chance for greater than 10 MeV proton events in the
latter half of the forecast period with the return of Region 69.

The greater than 2 MeV electron flux at geo-synchronous orbit is
expected to be at normal to moderate levels during most of the
forecast period.  However, high flux levels are possible beginning
09 September due to a recurring coronal hole.

The geomagnetic field is expected to be at quiet to unsettled levels
for most of the period.  Active conditions are possible on 05-08
September due to a recurring coronal hole.


.