Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 362 Issued at 2200Z on 27 Dec 2012
IA. Analysis of Solar Active Regions and Activity from 26/2100Z to
27/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C1 event observed at
27/0224Z from Region 1635 (N13W45). There are currently 5 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast: Solar activity is likely to be low with a
slight Chance for an M-class flare on days one, two, and three (28 Dec,
29 Dec, 30 Dec).
IIA. Geophysical Activity Summary 26/2100Z to 27/2100Z: 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 326 km/s at
27/0200Z. Total IMF reached 5.1 nT at 26/2206Z. The maximum southward
component of Bz reached -4.0 nT at 26/2227Z.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to unsettled levels for days one and two (28 Dec, 29 Dec)
due to effects from a weak coronal hole high speed stream. Quiet levels
are expected on day 3 (30 Dec).
III. Event probabilities 28 Dec-30 Dec
Class M 10/10/10
Class X 01/01/01
IV. Penticton 10.7 cm Flux
Observed 27 Dec 107
Predicted 28 Dec-30 Dec 110/110/110
90 Day Mean 27 Dec 118
V. Geomagnetic A Indices
Observed Afr/Ap 26 Dec 002/001
Estimated Afr/Ap 27 Dec 001/002
Predicted Afr/Ap 28 Dec-30 Dec 007/008-007/008-006/005
VI. Geomagnetic Activity Probabilities 28 Dec-30 Dec
A. Middle Latitudes
Minor Storm 01/01/01
Major-severe storm 01/01/01
B. High Latitudes
Minor Storm 20/15/10
Major-severe storm 10/05/05