:Product: 0824RSGA.txt :Issued: 2011 Aug 24 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 236 Issued at 2200Z on 24 Aug 2011 IA. Analysis of Solar Active Regions and Activity from 23/2100Z to 24/2100Z: Solar activity was low. The largest event in the last 24 hours was a C1/Sf event that originated from Region 1271 (N17W42) at 24/1633Z. This region has shown separation and penumbral decay in its intermediate spots. A back-sided, partial halo CME was observed at 24/0027Z. All other numbered regions on the disk showed various amounts of decay. IB. Solar Activity Forecast: Solar activity is expected to be very low to low with a slight chance for an M-class event from Region 1271 for the next three days (25-27 August). IIA. Geophysical Activity Summary 23/2100Z to 24/2100Z: The geomagnetic field was quiet to unsettled. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet for the next two days (25-26 August). Activity is expected to increase to quiet to unsettled on day three (27 August) due to a recurring coronal hole. III. Event Probabilities 25 Aug-27 Aug Class M 10/10/10 Class X 01/01/01 Proton 01/01/01 PCAF Green IV. Penticton 10.7 cm Flux Observed 24 Aug 104 Predicted 25 Aug-27 Aug 110/110/115 90 Day Mean 24 Aug 097 V. Geomagnetic A Indices Observed Afr/Ap 23 Aug 008/009 Estimated Afr/Ap 24 Aug 006/007 Predicted Afr/Ap 25 Aug-27 Aug 005/005-005/005-007/010 VI. Geomagnetic Activity Probabilities 25 Aug-27 Aug A. Middle Latitudes Active 15/15/20 Minor storm 01/01/05 Major-severe storm 01/01/01 B. High Latitudes Active 15/15/30 Minor storm 01/01/10 Major-severe storm 01/01/01