Joint USAF/NOAA Report of Solar and Geophysical Activity 7 January 2011

:Product: Report of Solar-Geophysical Activity
:Issued: 2011 Jan 07 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 007 Issued at 2200Z on 07 Jan 2011
IA. Analysis of Solar Active Regions and Activity from 06/2100Z
to 07/2100Z: Solar activity was at very low levels. Departing Region
1141 (N33, L=263) produced a B5 X-ray event at 07/1520Z as the
region rotated around the west limb. New Region 1143 (S22E16)
emerged on the disk as a D-type bi-polar group and exhibited steady
growth through the period. Region 1139 (S27W74) redeveloped spots
after a 6-day spotless plage interval. Region 1140 (N33W24)
redeveloped spots to the north of the large H spot and was
reclassified as a C-type bi-polar group. Region 1142 (S14W45)
decayed to a uni-polar group.
IB. Solar Activity Forecast: Solar activity is expected to remain
at predominately very low levels during the forecast period (08 – 10
January). A chance for isolated C-class activity exists all three
days.
IIA. Geophysical Activity Summary 06/2100Z to 07/2100Z:
Geomagnetic field activity ranged from quiet to active levels with a
minor storm interval observed between 06/2100 – 2400Z. The increase
in activity was due to the onset of a coronal hole high speed
stream. Solar wind velocities, as observed at the ACE satellite,
steadily increased throughout the period from about 450 km/s at
06/2100Z to a maximum of 627 km/s at 07/1545Z. Velocities remained
near 600 km/s through the end of the period. The Bz component of the
interplanetary magnetic field reached a maximum southward value of
-14nT at 06/2226Z and remained southward between -5 nT to -10 nT for
about 6 hours. For the remainder of the period, Bz fluctuated
between +/- 4 nT.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be at predominately quiet to unsettled levels all three
days of the forecast period (08 – 10 January). Isolated active to
minor storm periods are possible on 08 and 09 January. This activity
is due to continued effects of the coronal hole high speed stream.
III. Event Probabilities 08 Jan-10 Jan
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF Green
IV. Penticton 10.7 cm Flux
Observed 07 Jan 086
Predicted 08 Jan-10 Jan 086/086/084
90 Day Mean 07 Jan 084
V. Geomagnetic A Indices
Observed Afr/Ap 06 Jan 009/008
Estimated Afr/Ap 07 Jan 010/012
Predicted Afr/Ap 08 Jan-10 Jan 010/010-010/010-007/008
VI. Geomagnetic Activity Probabilities 08 Jan-10 Jan
A. Middle Latitudes
Active 20/20/15
Minor storm 10/10/05
Major-severe storm 01/01/01
B. High Latitudes
Active 30/30/25
Minor storm 15/15/10
Major-severe storm 01/01/01