:Product: Weekly Highlights and Forecasts
:Issued: 2000 Dec 12 2112 UT
Highlights of Solar and Geomagnetic Activity
04 - 10 December 2000

Solar activity ranged from very low to moderate levels. The period
began with activity at very low levels. Activity increased to low
levels on 05 December with isolated low-level C-class subflares. A
further increase to moderate levels occurred on 06 December by
virtue of an isolated M1/Sf flare at 06/2230 UTC from Region 9246
(S12, L = 248, class/area Eao/250 on 07 December). Region 9246 was
of moderate size and magnetic complexity, but gradually decaying at
the time of this flare. Solar activity dropped to low levels for the
rest of the period due to isolated to occasional C-class subflares.
The visible regions were either stable or declining at the close of
the summary period.

Data were available from the Advanced Composition Explorer (ACE)
spacecraft for most of the period. Solar wind conditions were
largely unremarkable through 06 December with the exception of a few
periods of sustained southward IMF Bz with deflections to minus 09
nT (GSM). A recurrent coronal hole wind stream began on 07 December
and continued through the rest of the period with velocities peaking
at 710 km/sec during 09 - 10 December.

There were no proton events detected at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit was at
normal to moderate levels.

The geomagnetic field was at mostly quiet to unsettled levels during
4 - 7 December with isolated active periods. The field was disturbed
during 8 - 9 December due to a  high speed stream associated with a
recurrent, negative polarity coronal hole. Unsettled to active
levels occurred during this period with brief minor to major storm
intervals detected at some high latitude stations. Activity subsided
to quiet to unsettled levels on the last day of the period.

Forecast of Solar and Geomagnetic Activity
13 December 2000 - 08 January 2001

Solar activity is expected to be at low to moderate levels. An
increasing trend is expected to begin 13 December with the return of
previously active longitudes. There will also be a chance for a
major flare during the first half of  the period.

Chances for a proton event are expected to increase during the first
half of the period 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 05 - 06 January. Otherwise,
normal to moderate fluxes are expected.

Active levels will be possible around 04 - 05 January 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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