:Product: Weekly Highlights and Forecasts
:Issued: 2000 Dec 05 2112 UT
Highlights of Solar and Geomagnetic Activity
27 November - 03 December 2000

Solar activity was at low to moderate levels. Activity was at low
levels during 27 - 29 November due to C-class flares from a few
regions of moderate size and complexity. Flare producing regions of
note included Region 9236 (N20, L = 352, class/area Eko/630 on 27
November), which was responsible for last week's major flare
activity, and Region 9246 (S12, L = 248, class/area Eai/220 on 30
November). Region 9236 was large and magnetically complex, but
slowly decayed before making an uneventful west limb passage on 30
November. Region 9246 was moderate in size and magnetic complexity
and in a development phase until 01 December, then stabilized. It
produced a C9/Sf flare at 29/0629 UTC with an associated Type II
radio sweep. Activity rose to moderate levels on 30 November as
Region 9246 produced an M1/Sf flare at 30/2038 UTC. It may have also
been responsible for an optically uncorrelated M1 X-ray flare at
30/0925 UTC. Activity was low during the rest of the period due to
isolated C-class X-ray flares, most of which were optically
uncorrelated.

Data were available from the Advanced Composition Explorer (ACE)
spacecraft for most of the period. CMEs associated with last week's
major flare activity passed the spacecraft during the first two days
of the period with increased velocities (peaks to 670 km/sec) and
densities along with variable IMF Bz and solar sector. Maximum
southerly deflections during this period reached minus 15 nT (GSM).
A period of prolonged southward IMF Bz occurred during 03 December
with deflections to minus 10 nT. Positive polarity (away) sector
conditions began on 01 December.

The greater than 10 MeV proton event that began at 24/1520 UTC ended
at 29/0200 UTC. The greater than 100 MeV proton flux was enhanced at
the beginning of the period, then declined to background levels by
28 November.

The greater than 2 MeV electron flux at geosynchronous orbit was at
normal to moderate levels during 27 - 28 November, then decreased to
normal levels for the balance of the period.

The geomagnetic field was disturbed during 27 - 29 November due to
CME passages associated with major flares from Region 9236. Active
to severe storm levels were detected during the disturbance.
Activity decreased to mostly quiet levels during 30 November - 02
December. Unsettled to briefly active levels occurred on 03 December
due to prolonged periods of southward IMF Bz.

Forecast of Solar and Geomagnetic Activity
06 December 2000 - 01 January 2001

Solar activity is expected to be at mostly low levels through 12
December. Low to moderate activity is expected during the rest of
the period due to the return of previously active longitudes.

Chances for a proton event are expected to increase beginning around
13 December due to the return of previously active longitudes.

The greater than 2 MeV electron flux at geosynchronous orbit may
reach moderate to high levels during 10 - 11 December. Otherwise,
normal to moderate fluxes are expected.

Active levels will be possible around 09 December due to coronal hole
effects. Quiet to unsettled levels are expected during the rest of
the period, barring an Earth-directed CME.

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