Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 041 Issued at 2200Z on 10 Feb 2012
IA. Analysis of Solar Active Regions and Activity from 09/2100Z
to 10/2100Z: Solar activity was low due to C-class x-ray events from
Region 1415 (N08W84). Region 1416 (S17E10) continues to evolve
developing a beta-gamma magnetic configuration. New Region 1417
(N18E59) rotated onto the disk as a B-type group. As asymmetric,
full-halo CME was observed lifting off the NE limb, first seen in
SOHO LASCO C2 imagery at 09/2117Z. The source region for this event
appears to be located to the southwest of Region 1417. A second CME
was observed in STEREO-A and B COR2 imagery, first seen on the Ahead
spacecraft at 10/1154Z. The source of this CME appears to be a 23
degree long filament eruption, centered near S31E29. Analysis is
ongoing on the geoeffective potential of these CMEs.
IB. Solar Activity Forecast: Solar activity is expected to be low
with a slight chance for M-class activity for the next three days
(11 - 13 February) due to the return of old Region 1402 (N26,
L=218).
IIA. Geophysical Activity Summary 09/2100Z to 10/2100Z:
The geomagnetic field was at quiet to unsettled levels. ACE satellite
solar wind velocities were steady through the period at about 450
km/s. The Bz component of the interplanetary magnetic field was
mostly north at about 5 nT with brief southward excursions to -4 nT.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be mostly quiet on day one (11 February) through midday
on day two (12 February). By midday on day two, and through day
three (13 February), field activity is expected to increase to quiet
to unsettled levels with high latitude active intervals. This
increase in activity is due to a recurrent coronal high speed stream
that is expected to rotate into a geoeffective position.
III. Event Probabilities 11 Feb-13 Feb
Class M 05/10/10
Class X 01/01/01
Proton 01/01/01
PCAF green
IV. Penticton 10.7 cm Flux
Observed 10 Feb 111
Predicted 11 Feb-13 Feb 115/120/120
90 Day Mean 10 Feb 135
V. Geomagnetic A Indices
Observed Afr/Ap 09 Feb 004/006
Estimated Afr/Ap 10 Feb 004/005
Predicted Afr/Ap 11 Feb-13 Feb 004/005-006/008-007/008
VI. Geomagnetic Activity Probabilities 11 Feb-13 Feb
A. Middle Latitudes
Active 05/30/30
Minor storm 01/10/10
Major-severe storm 01/01/01
B. High Latitudes
Active 10/40/40
Minor storm 05/20/20
Major-severe storm 01/01/01
