:Product: 20020221RSGA.txt :Issued: 2002 Feb 21 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 052 Issued at 2200Z on 21 Feb 2002 IA. Analysis of Solar Active Regions and Activity from 20/2100Z to 21/2100Z: Solar activity was moderate. Region 9825 (N13W90) continued to be the region of primary concern as it rotated around the NW limb. The three M-class flares this period all appear to have originated from this region. The largest was an M3 at 21/1226Z. A prominence erupted from this area at 21/0608Z, followed by a large filament eruption at around 21/1100Z. Region 9335 (S09W75) grew rather quickly this period and produced some small flares as it approaches the west limb. New Regions 9838 (N05W18), 9839 (S16E06), and 9840 (S12E72), were numbered today. IB. Solar Activity Forecast: Solar activity is expected to continue at moderate to high levels. We may continue to experience activity from behind the NW limb for the next day or so. Region 9835 has potential to produce M-class activity with a small chance for a major flare. IIA. Geophysical Activity Summary 20/2100Z to 21/2100Z: The geomagnetic field was quiet to unsettled. The greater than 10 MeV protons at geosynchronous orbit remain elevated following the small proton event that began and ended between 20/0730 - 0800Z. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to continue at quiet to unsettled levels through day one. Active conditions are expected on day two due to an expected CME passage associated with the M5/1n flare that occurred on 20/0612Z. Quiet to unsettled conditions are expected to return by day three. III. Event Probabilities 22 Feb-24 Feb Class M 70/65/60 Class X 10/10/05 Proton 10/10/05 PCAF yellow IV. Penticton 10.7 cm Flux Observed 21 Feb 201 Predicted 22 Feb-24 Feb 205/200/200 90 Day Mean 21 Feb 223 V. Geomagnetic A Indices Observed Afr/Ap 20 Feb 006/008 Estimated Afr/Ap 21 Feb 008/008 Predicted Afr/Ap 22 Feb-24 Feb 010/015-015/020-010/010 VI. Geomagnetic Activity Probabilities 22 Feb-24 Feb A. Middle Latitudes Active 20/40/20 Minor storm 10/30/15 Major-severe storm 05/15/10 B. High Latitudes Active 25/50/25 Minor storm 15/35/20 Major-severe storm 10/15/10