:Product: 20011023RSGA.txt :Issued: 2001 Oct 23 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 296 Issued at 2200Z on 23 Oct 2001 IA. Analysis of Solar Active Regions and Activity from 22/2100Z to 23/2100Z: Solar activity was at high levels. The largest flare for the period was from Region 9672 (N18E00), which produced an M6/1b flare at 23/0223 UTC and an M1/Sn flare at 23/0023 UTC. The magnetic beta-gamma-delta configuration appears to have grown stronger since the latest M-class flare occurrence from this region. Multiple C-class flares were observed during the period. Region 9676 (N14E30) produced a C7/1f at 23/0803 UTC and Region 9678 (N07E48) produced several minor C-class flares early in period. Three new regions were numbered today, Region 9678, Region 9679 (S10E58), and Region 9680 (N22E61). IB. Solar Activity Forecast: Solar activity is expected to remain at moderate to high levels. Region 9672 continues to show a strong delta magnetic configuration. IIA. Geophysical Activity Summary 22/2100Z to 23/2100Z: The geomagnetic field was at quiet to active levels with an isolated period (23/0300 to 0600 UTC) of minor storm conditions at USAF planetary. The greater than 10 MeV proton flux event at geosynchronous orbit exceeded threshold at 22/1910 UTC, and reached a maximum of 24 pfu at 22/2130 UTC. The event ended at 23/0115 UTC. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to major storm levels. The M6/2n and the X1/2b flares from Region 9672 (that occurred during the last forecast period) have both produced CME activity on LASCO/EIT imagery. Analysis indicates that both shock arrivals may occur between the early and middle period of day one resulting in storm conditions to occur on day one and two of the forecast period. III. Event Probabilities 24 Oct-26 Oct Class M 80/80/70 Class X 40/40/25 Proton 30/30/25 PCAF yellow IV. Penticton 10.7 cm Flux Observed 23 Oct 226 Predicted 24 Oct-26 Oct 225/220/220 90 Day Mean 23 Oct 193 V. Geomagnetic A Indices Observed Afr/Ap 22 Oct 033/066 Estimated Afr/Ap 23 Oct 015/017 Predicted Afr/Ap 24 Oct-26 Oct 030/040-025/040-012/012 VI. Geomagnetic Activity Probabilities 24 Oct-26 Oct A. Middle Latitudes Active 30/40/30 Minor storm 40/30/10 Major-severe storm 15/10/01 B. High Latitudes Active 30/50/40 Minor storm 50/40/15 Major-severe storm 20/05/01