Joint USAF/NOAA Report of Solar and Geophysical Activity 28 December 2010

:Product: Report of Solar-Geophysical Activity
: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 Earth’s 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