:Product: 1228RSGA.txt
:Issued: 2010 Dec 28 2200 UTC
# Prepared jointly by the U.S. Dept. of Commerce, NOAA,
# Space Weather Prediction Center and the U.S. Air Force.
#
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 362 Issued at 2200Z on 28 Dec 2010
IA.  Analysis of Solar Active Regions and Activity from  27/2100Z
to 28/2100Z:  Solar activity was very low. Region 1138 (N13W26)
developed a beta-gamma magnetic configuration during the period, but
the region remained quiet.
IB.  Solar Activity Forecast:  Solar activity is expected to be at
predominately very low levels for the next three days (29 - 31
December). A slight chance for C-class activity exists from Region
1138.
IIA.  Geophysical Activity Summary 27/2100Z to 28/2100Z:
The geomagnetic field ranged from quiet to minor storm levels during
the period. At approximately 28/0930Z, effects from the 23 December
CME impacted Earths magnetic field. Observations from the ACE
spacecraft indicated a sharp decrease in the Bz component of the IMF
(-13nT at 28/1401Z) while the Bt component reached a maximum value
of 14nT at 28/1315Z. The field responded with an isolated minor
storm period from 28/1200 - 1500Z at all latitudes. Thereafter,
storm conditions diminished to unsettled to active levels through
the end of the summary period.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be at quiet to unsettled levels for day one of the
forecast period (29 December) and mostly quiet for days two and
three (30 - 31 December).
III.  Event Probabilities 29 Dec-31 Dec
Class M    01/01/01
Class X    01/01/01
Proton     01/01/01
PCAF       Green
IV.  Penticton 10.7 cm Flux
Observed           28 Dec 081
Predicted   29 Dec-31 Dec  082/084/084
90 Day Mean        28 Dec 083
V.  Geomagnetic A Indices
Observed Afr/Ap 27 Dec  001/002
Estimated Afr/Ap 28 Dec  009/012
Predicted Afr/Ap 29 Dec-31 Dec  005/005-005/005-005/005
VI.  Geomagnetic Activity Probabilities 29 Dec-31 Dec
A.  Middle Latitudes
Active                05/05/05
Minor storm           01/01/01
Major-severe storm    01/01/01
B.  High Latitudes
Active                10/10/10
Minor storm           01/01/01
Major-severe storm    01/01/01