:Product: 20031020RSGA.txt :Issued: 2003 Oct 20 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 293 Issued at 2200Z on 20 Oct 2003 IA. Analysis of Solar Active Regions and Activity from 19/2100Z to 20/2100Z: Solar activity has been low to moderate. Region 484 (N06E41) has increased again to 1500 millionths with over 56 sunspots and a strong Beta-Gamma-Delta magnetic configuration. It has produced several C-class flares and a long-duration M-class flare at 0722 UTC. Further analysis of a CME which occurred 18 October around 1830 UTC indicates that a faint portion was Earth-directed. IB. Solar Activity Forecast: Solar activity is expected to be low to moderate. There's a slight chance for another isolated X-class flare and an even lesser chance of proton activity from Region 484. IIA. Geophysical Activity Summary 19/2100Z to 20/2100Z: The geomagnetic field has been at low to minor storm levels. Another favorably positioned coronal hole is perpetuating the high speed solar wind stream, and is continuing to keep the geomagnetic field disturbed. The interplanetary magnetic field has settled to a low value of around 8 nT, which is keeping the overall disturbance at a maximum of minor storm levels. The greater than 2 MeV electron flux at geosynchronous orbit reached high levels today. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at active to minor storm levels for the next 24 hours, dropping to mostly low with a chance for isolated periods of minor storming during day two. On day three, the faintly Earth-directed CME from 18 October should impact the magnetic field, and is likely to increase activity to mostly active to minor storming, with a chance for an isolated period of major storming. III. Event Probabilities 21 Oct-23 Oct Class M 70/70/70 Class X 15/15/15 Proton 10/10/10 PCAF green IV. Penticton 10.7 cm Flux Observed 20 Oct 135 Predicted 21 Oct-23 Oct 130/130/130 90 Day Mean 20 Oct 115 V. Geomagnetic A Indices Observed Afr/Ap 19 Oct 022/032 Estimated Afr/Ap 20 Oct 020/025 Predicted Afr/Ap 21 Oct-23 Oct 025/030-015/020-020/020 VI. Geomagnetic Activity Probabilities 21 Oct-23 Oct A. Middle Latitudes Active 35/35/35 Minor storm 30/30/30 Major-severe storm 20/10/20 B. High Latitudes Active 25/30/30 Minor storm 25/20/20 Major-severe storm 15/10/10