Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 21 December 2012

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 356 Issued at 2200Z on 21 Dec 2012

IA. Analysis of Solar Active Regions and Activity from 20/2100Z to
21/2100Z: Solar activity has been at very low levels for the past 24
hours. There are currently 3 numbered sunspot regions on the disk.
IB. Solar Activity Forecast: Solar activity is likely to be low on days
one, two, and three (22 Dec, 23 Dec, 24 Dec).

IIA. Geophysical Activity Summary 20/2100Z to 21/2100Z: The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed,
as measured by the ACE spacecraft, reached a peak speed of 522 km/s at
20/2328Z. Total IMF reached 5.1 nT at 20/2150Z. The maximum southward
component of Bz reached -3.3 nT at 20/2218Z. Electrons greater than 2
MeV at geosynchronous orbit reached a peak level of 147 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet levels for day one (22 Dec) and at quiet to unsettled
levels for days two and three (23 Dec, 24 Dec).

III. Event probabilities 22 Dec-24 Dec
Class M 05/05/05
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 21 Dec 115
Predicted 22 Dec-24 Dec 115/115/115
90 Day Mean 21 Dec 120

V. Geomagnetic A Indices
Observed Afr/Ap 20 Dec 007/008
Estimated Afr/Ap 21 Dec 005/005
Predicted Afr/Ap 22 Dec-24 Dec 006/005-006/008-006/008

VI. Geomagnetic Activity Probabilities 22 Dec-24 Dec
A. Middle Latitudes
Active 05/10/10
Minor Storm 01/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 10/20/20
Major-severe storm 05/10/10