Joint USAF/NOAA Report of Solar and Geophysical Activity 16 September 2012

:Product: Report of Solar-Geophysical Activity
:Issued: 2012 Sep 16 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 260 Issued at 2200Z on 16 Sep 2012
IA. Analysis of Solar Active Regions and Activity from 15/2100Z
to 16/2100Z: Solar activity was very low. New Region 1573 (N17E62 –
Axx/alpha) produced occasional B-class flares as it rotated into
view. Region 1566 (N23W89 – Hrx/alpha) produced a B-class flare as
it approached the west limb. Region 1569 (S12W13 – Cso/beta) showed
gradual spot and penumbral decay in its intermediate and trailer
portions. New Region 1574 (S25W15 – Bxo/beta), a small
reverse-polarity group, was also numbered. No Earth-directed CME activity
occurred during the period.
IB. Solar Activity Forecast: Solar activity is expected to be very
low through the period (17 – 19 September) with a chance for a
C-class flare.
IIA. Geophysical Activity Summary 15/2100Z to 16/2100Z:
Geomagnetic field activity was at quiet to unsettled levels. An
increase to unsettled levels occurred late in the period associated
with the onset of a solar sector boundary crossing (SSBC).
Intermittent periods of weakly-southward IMF Bz along with minor
increases in solar wind speeds and IMF Bt were associated with the
SSBC.
IIB. Geophysical Activity Forecast: Geomagnetic field activity is
expected to remain at quiet to unsettled levels on day 1 (17
September) due to minor changes in the solar wind. A decrease to
quiet levels is expected on day 2 (18 September). Activity is
expected to increase to quiet to unsettled levels on day 3 (19
September), with a slight chance for active levels, as a coronal
hole high-speed stream begins to disturb the field.
III. Event Probabilities 17 Sep-19 Sep
Class M 10/10/10
Class X 01/01/01
Proton 01/01/01
PCAF green
IV. Penticton 10.7 cm Flux
Observed 16 Sep 097
Predicted 17 Sep-19 Sep 095/095/100
90 Day Mean 16 Sep 122
V. Geomagnetic A Indices
Observed Afr/Ap 15 Sep 005/006
Estimated Afr/Ap 16 Sep 006/008
Predicted Afr/Ap 17 Sep-19 Sep 007/010-006/005-007/008
VI. Geomagnetic Activity Probabilities 17 Sep-19 Sep
A. Middle Latitudes
Active 10/10/10
Minor storm 01/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 20/15/15
Minor storm 20/15/25
Major-severe storm 10/05/15