:Product: 0811RSGA.txt :Issued: 2012 Aug 11 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 224 Issued at 2200Z on 11 Aug 2012 IA. Analysis of Solar Active Regions and Activity from 10/2100Z to 11/2100Z: Solar activity was moderate. Region 1540 (S25W50) produced a long duration M1/2n flare at 11/1220Z. A faint CME was first observed in LASCO C2 imagery emerging from the southwest at 11/1325Z. Analysis is underway to determine the potential geoeffectiveness. Region 1542 (S31W33) produced a C2/1f flare at 11/1642Z. IB. Solar Activity Forecast: Solar activity is expected to be low with a slight chance for an M-class event for the next three days (12-14 August). IIA. Geophysical Activity Summary 10/2100Z to 11/2100Z: The geomagnetic field was quiet. The Bz component of the interplanetary magnetic field shifted southward to around -5nT beginning at 11/08Z and remained there through the period. Solar wind speed remained between 300-350 km/s. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels, with a chance for isolated active periods, for the next three days (12-14 August). The elevated activity is associated with the arrival of a recurrent coronal hole high speed stream. III. Event Probabilities 12 Aug-14 Aug Class M 15/15/10 Class X 01/01/01 Proton 01/01/01 PCAF Green IV. Penticton 10.7 cm Flux Observed 11 Aug 120 Predicted 12 Aug-14 Aug 120/120/115 90 Day Mean 11 Aug 127 V. Geomagnetic A Indices Observed Afr/Ap 10 Aug 004/004 Estimated Afr/Ap 11 Aug 004/005 Predicted Afr/Ap 12 Aug-14 Aug 010/010-008/008-007/008 VI. Geomagnetic Activity Probabilities 12 Aug-14 Aug A. Middle Latitudes Active 15/20/15 Minor storm 01/01/01 Major-severe storm 01/01/01 B. High Latitudes Active 20/20/20 Minor storm 30/30/30 Major-severe storm 25/25/15