Report of Solar-Geophysical Activity

Issued: 2012 Sep 13 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 257 Issued at 2200Z on 13 Sep 2012

IA.  Analysis of Solar Active Regions and Activity from  12/2100Z
to 13/2100Z:  Solar activity was low. Region 1564 (S11, L=072), which
rotated around the west limb yesterday, produced the largest event,
a long duration C2 event at 13/0508Z. Region 1569 (S13E27) increased
in magnetic complexity and is now considered a beta-gamma type
group. A filament eruption occurred near N22W20 at approximately
05/0640Z. The associated CME had an estimated speed of 536 km/s.
IB.  Solar Activity Forecast:  Solar activity is expected to be low
with a slight chance for M-class flares for the next three days
(14-16 September), mainly from Region 1569.
IIA.  Geophysical Activity Summary 12/2100Z to 13/2100Z:
The geomagnetic field was mostly quiet with an isolated unsettled
period observed from 13/0000-0300Z. Solar wind speeds increased from
approximately 290 km/s to 400 km/s due to the effects of a weak
coronal hole high speed stream (CH HSS).
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be quiet on day one (14 September). Quiet to unsettled
conditions are expected on day two (15 September) due to effects
from another CH HSS. Activity is expected to increase to unsettled
levels on day three (16 September) with a chance for active periods
due the arrival of the CME associated with today's filament
eruption.
III.  Event Probabilities 14 Sep-16 Sep
Class M    20/20/20
Class X    01/01/01
Proton     01/01/01
PCAF       Green
IV.  Penticton 10.7 cm Flux
Observed           13 Sep 099
Predicted   14 Sep-16 Sep  100/100/095
90 Day Mean        13 Sep 123
V.  Geomagnetic A Indices
Observed Afr/Ap 12 Sep  005/006
Estimated Afr/Ap 13 Sep  005/006
Predicted Afr/Ap 14 Sep-16 Sep  005/005-009/010-011/012
VI.  Geomagnetic Activity Probabilities 14 Sep-16 Sep
A.  Middle Latitudes
Active                05/10/30
Minor storm           01/01/10
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/20
Minor storm           15/15/30
Major-severe storm    10/10/30