:Product: 0818RSGA.txt
:Issued: 2012 Aug 18 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 231 Issued at 2200Z on 18 Aug 2012
IA.  Analysis of Solar Active Regions and Activity from  17/2100Z
to 18/2100Z:  Solar activity was high.  Region 1548 (N19E86) produced
an M5/Sf flare at 18/0102Z, accompanied by a Tenflare (150 pfu).  An
M1/Sn flare from the same region followed at 18/0323Z, also
accompanied by a Tenflare (120 pfu).  Finally, an M2/1N occurred at
18/1607Z.  Several coronal mass ejections (CMEs) were observed in
the past 24 hours, none appear to have a geoeffective component. 
SDO 304 imagery showed a filament eruption in the vicinity of Region
1543 (N23W74) around 17/16Z.  A CME was subsequently observed in
LASCO C2 coronagraph imagery at 17/1836Z, and in LASCO C3 imagery at
17/1918Z.  A second filament eruption and CME was observed near
Region 1543 between 17/22Z and 18/0034Z.  It was visible in STEREO-B
COR2 imagery at 18/0110Z and in LASCO C3 imagery at 18/0454Z.  This
CME was directed well north of the ecliptic.
IB.  Solar Activity Forecast:  Solar activity is expected to be low
with moderate activity likely for the next three days (19-21
August).
IIA.  Geophysical Activity Summary 17/2100Z to 18/2100Z:
The geomagnetic field was quiet to active.  Solar wind speed at the
ACE spacecraft ranged between about 350-420 km/s during the period. 
The Bz component of the interplanetary magnetic field ranged between
-8 and +12 nT.  Solar wind density at ACE increased sharply after
18/19Z.  The geomagnetic field reached active levels during the last
period (18-21Z) coincident with a change to the positive sector and
the arrival of the corotating active region.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be quiet to unsettled for the next three days (19-21
August) as a corotating interaction region and coronal hole high
speed stream become geoeffective.
III.  Event Probabilities 19 Aug-21 Aug
Class M    55/55/55
Class X    05/05/05
Proton     01/01/01
PCAF       Green
IV.  Penticton 10.7 cm Flux
Observed           18 Aug 097
Predicted   19 Aug-21 Aug  100/100/100
90 Day Mean        18 Aug 125
V.  Geomagnetic A Indices
Observed Afr/Ap 17 Aug  011/011
Estimated Afr/Ap 18 Aug  009/011
Predicted Afr/Ap 19 Aug-21 Aug  010/012-011/012-007/008
VI.  Geomagnetic Activity Probabilities 19 Aug-21 Aug
A.  Middle Latitudes
Active                20/20/10
Minor storm           05/05/05
Major-severe storm    01/01/01
B.  High Latitudes
Active                20/20/15
Minor storm           30/30/20
Major-severe storm    25/25/15