:Product: 20021012RSGA.txt :Issued: 2002 Oct 12 2200 UTC # Prepared jointly by the U.S. Dept. of Commerce, NOAA, # Space Environment Center and the U.S. Air Force. # Joint USAF/NOAA Report of Solar and Geophysical Activity SDF Number 285 Issued at 2200Z on 12 Oct 2002 IA. Analysis of Solar Active Regions and Activity from 11/2100Z to 12/2100Z: Solar activity was low. The largest event of the period was a C2.6 flare at 12/1922UTC, without a correlating optical report. Region 149 (N16E34) increased somewhat in size today. Region 139 (N08W59) remains the largest group on the visible disk, retaining mixed polarities within its penumbral area, but appears relatively stable and quiescent. Two new regions were numbered today, Regions 157 (N17E49) and 158 (S08E80). The latter appears as a large unipolar spot near the east limb, which may be the leader of a larger group rotating onto the visible disk. IB. Solar Activity Forecast: Solar activity is expected to be predominantly low, with a chance for isolated moderate activity. Regions 149 and 139 are both potential sources for isolated moderate flares during the period. Region 139 will rotate off the visible disk by the end of the period. IIA. Geophysical Activity Summary 11/2100Z to 12/2100Z: The geomagnetic field was mainly quiet to unsettled, with one active period observed during 12/0900-1200 UTC. Greater than 2 MeV electron flux at geosynchronous orbit briefly reached high levels and exceeded event threshold today. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be mainly quiet to unsettled for the next three days. III. Event Probabilities 13 Oct-15 Oct Class M 30/30/25 Class X 05/05/01 Proton 05/05/01 PCAF green IV. Penticton 10.7 cm Flux Observed 12 Oct 180 Predicted 13 Oct-15 Oct 185/180/175 90 Day Mean 12 Oct 182 V. Geomagnetic A Indices Observed Afr/Ap 11 Oct 005/008 Estimated Afr/Ap 12 Oct 008/008 Predicted Afr/Ap 13 Oct-15 Oct 007/008-007/008-007/008 VI. Geomagnetic Activity Probabilities 13 Oct-15 Oct A. Middle Latitudes Active 15/15/15 Minor storm 05/05/05 Major-severe storm 01/01/01 B. High Latitudes Active 20/20/20 Minor storm 05/05/05 Major-severe storm 01/01/01