:Product: 0812RSGA.txt :Issued: 2012 Aug 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 225 Issued at 2200Z on 12 Aug 2012 IA. Analysis of Solar Active Regions and Activity from 11/2100Z to 12/2100Z: Solar activity was very low. Region 1542 (S13W04) produced a B8/Sf at 12/1344Z, and several other Sf optical flares throughout the period. Region 1543 (N20E07) remained the largest region on the disk. Both Regions 1542 and 1543 ended the period with beta-gamma magnetic configurations. IB. Solar Activity Forecast: Solar activity is expected to be low with a slight chance for an M-class event. IIA. Geophysical Activity Summary 11/2100Z to 12/2100Z: The geomagnetic field was quiet. A solar sector boundary change, from positive to negative occurred at approximately 12/1330Z. Wind speed at the ACE spacecraft rose from approximatly 300 km/s at the beginning of the period to end near 400 km/s. The Bz component of the interplanetary magnetic field was slightly negative from 11/21Z to 12/06Z, then ranged from +/- 5nT for the remainder of the period. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet to unsettled, with a slight chance for an active period, for days 1 and 2 (13-14 August) before becoming mostly quiet on day 3 (15 August). The increased activity on the first two days is expected from the influence of a weak high speed stream. III. Event Probabilities 13 Aug-15 Aug Class M 15/10/05 Class X 01/01/01 Proton 01/01/01 PCAF Green IV. Penticton 10.7 cm Flux Observed 12 Aug 112 Predicted 13 Aug-15 Aug 115/110/100 90 Day Mean 12 Aug 127 V. Geomagnetic A Indices Observed Afr/Ap 11 Aug 005/004 Estimated Afr/Ap 12 Aug 006/007 Predicted Afr/Ap 13 Aug-15 Aug 008/008-009/008-006/005 VI. Geomagnetic Activity Probabilities 13 Aug-15 Aug A. Middle Latitudes Active 10/10/05 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 15/10/05