Joint USAF/NOAA Report of Solar and Geophysical Activity 12 September 2012

:Product: Report of Solar-Geophysical Activity
:Issued: 2012 Sep 12 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 256 Issued at 2200Z on 12 Sep 2012
IA. Analysis of Solar Active Regions and Activity from 11/2100Z
to 12/2100Z: Solar activity was at low levels. Region 1564 (S13W95)
was the most active sunspot group, producing several C-class flares
as it rotated off the west limb. The largest flare produced was a
long duration C4 at 11/2207Z. Two new B-type Cso regions were
numbered; Region 1570 (S13W34) emerged while 1571 (S12E57) rotated
onto the disk. There was no Earth directed CME activity during the
period.
IB. Solar Activity Forecast: Solar activity is expected to be low
with a slight chance for an isolated M-class flare on day 1 (13
September). M-class probability is expected to decrease for the
second and third days (14-15 September) as Region 1564 rotates
further beyond the limb.
IIA. Geophysical Activity Summary 11/2100Z to 12/2100Z:
Geomagnetic field activity was at mostly quiet levels. There was an
isolated period of major storming at high latitudes during
12/09-12Z. A solar sector boundary crossing was observed at the ACE
spacecraft at about 11/2200Z. The greater than 2 MeV electron flux
at geosynchronous orbit reached high levels during the period.
IIB. Geophysical Activity Forecast: Geomagnetic activity is
expected to be quiet with a slight chance for unsettled levels on
days 1 and 2 (13-14 September). An increase to quiet to unsettled
levels with a slight chance for an active period is expected on the
third day (15 September) due to a favorably positioned coronal hole.
III. Event Probabilities 13 Sep-15 Sep
Class M 10/05/05
Class X 01/01/01
Proton 01/01/01
PCAF Green
IV. Penticton 10.7 cm Flux
Observed 12 Sep 103
Predicted 13 Sep-15 Sep 100/095/095
90 Day Mean 12 Sep 123
V. Geomagnetic A Indices
Observed Afr/Ap 11 Sep 003/002
Estimated Afr/Ap 12 Sep 004/006
Predicted Afr/Ap 13 Sep-15 Sep 004/005-004/007-009/010
VI. Geomagnetic Activity Probabilities 13 Sep-15 Sep
A. Middle Latitudes
Active 05/05/10
Minor storm 01/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor storm 15/15/15
Major-severe storm 05/05/10