:Product: 0328RSGA.txt :Issued: 2011 Mar 28 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 087 Issued at 2200Z on 28 Mar 2011 IA. Analysis of Solar Active Regions and Activity from 27/2100Z to 28/2100Z: Solar activity was at low levels. Region 1181 (S26E31) produced a C1/Sf flare at 27/2326Z while Region 1176 (S17W11) produced a C1 X-ray event at 28/1139Z. Region 1176 decayed in area and spot count, but maintained a complex beta-gamma magnetic configuration. Region 1183 (N15E54) indicated growth in area and spot count as it continued to rotate onto the disk. At 28/1405Z, a filament eruption was observed in STEREO-B EUVI 195 near N20, L=030. Associated with this eruption was a CME that lifted off the NE limb, first observed in LASCO C3 imagery at 28/1818Z. Due to the source of this CME, it is not Earth-directed. No new regions were numbered during the period. IB. Solar Activity Forecast: Solar activity is expected to be low all three days of the forecast period (29 - 31 March). A chance exists all three days for isolated M-class activity. IIA. Geophysical Activity Summary 27/2100Z to 28/2100Z: The geomagnetic field was quiet. ACE solar wind velocities remained low and steady, only varying between 340 km/s to 370 km/s. The Bz component of the IMF ranged between +/- 4 nT. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet for day one (29 March). By days two and three (30 - 31 March), quiet to unsettled conditions, with isolated active periods, are expected due to the arrival of a recurrent coronal hole high speed stream. III. Event Probabilities 29 Mar-31 Mar Class M 35/50/50 Class X 01/05/05 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 28 Mar 119 Predicted 29 Mar-31 Mar 120/130/135 90 Day Mean 28 Mar 097 V. Geomagnetic A Indices Observed Afr/Ap 27 Mar 002/002 Estimated Afr/Ap 28 Mar 002/002 Predicted Afr/Ap 29 Mar-31 Mar 005/005-010/010-010/010 VI. Geomagnetic Activity Probabilities 29 Mar-31 Mar A. Middle Latitudes Active 10/20/20 Minor storm 01/05/05 Major-severe storm 01/01/01 B. High Latitudes Active 15/25/25 Minor storm 01/10/10 Major-severe storm 01/01/01