:Product: Weekly Highlights and Forecasts
:Issued: 2011 Dec 06 1957 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC contact on the Web
# http://www.swpc.noaa.gov/weekly.html
#
# Weekly Highlights and Forecasts
#
Highlights of Solar and Geomagnetic Activity
28 November - 04 December 2011

Solar activity was low all week. On average, seven small and
magnetically simple spotted regions were present at any given time
during the period. Of these, Region 1363 (S22, Lo=108,
class/area=Eki/430 on 04 December) was the most productive, with
five C-class flares and 4 optical flares to its credit. It appeared
on the disk on 29 November as a small Hsx-alpha group and ended the
period as the largest and most magnetically complex (beta-gamma)
group on the disk. Despite its size and complexity, Region 1363 did
not produce the largest x-ray flare of the week. That honor belongs
to Region 1362 (N08, Lo=131, class/area=Eso/220 on 03 December)
which produced C4 04/1615Z. The second largest x-ray flare of the
period, a C3 from Region 1364 (N18, Lo=105, class/area=Hsx/60 on 30
November) occurred on 30/2028Z. At least one CME was observed each
day in coronagraph imagery, mostly attributed to filament eruptions.
None of the CMEs had any significant geoeffective component.

The greater than 10 MeV protons at 10 pfu exceeded threshold during
the period. The event began at 26/1125Z, reached a maximum flux of
80 pfu at 27/0125Z and ended at 28/0145Z. This event was associated
with a filament eruption observed early on 26 November.

The greater than 2 MeV electron flux at geosynchronous orbit was at
normal levels 28 November - 01 December and at moderate levels on 27
November and 02 - 03 December.

The geomagnetic field on 27 November was at quiet to unsettled
levels, with isolated high latitude active periods. The disturbed
conditions were caused by a CIR in advance of a weak CH HSS. Most of
28 November was quiet. A 45 nT Sudden Impulse at the Boulder
magnetometer at 28/2154Z signaled the arrival of a CME from 26
November. Unsettled to minor storm periods followed at all
latitudes. Quiet to unsettled levels, with isolated high latitude
active periods, returned by midday on 29 November and lasted until
early on 03 December. The exception was the latter half of 30
November when a solar sector boundary crossing and prolonged
southward IMF Bz triggered minor to major storm periods at high
latitudes. Active to minor storm conditions were also observed at
high latitudes between 03/0900-1500Z with the passage of a transient
feature. The field returned to quiet to unsettled levels for the
remainder.

Forecast of Solar and Geomagnetic Activity
07 December - 02 January 2012

Solar activity is expected to be at predominately low levels with a
chance for isolated M-class activity through the forecast period

No proton events are expected at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit is
expected to be at normal to moderate levels the entire forecast
period

The geomagnetic field is expected to be at mostly quiet to unsettled
levels through most of the forecast period. Coronal hole high speed
streams are expected to bring active conditions on 14 November and
again on 26-29 December.