:Product: 20010904RSGA.txt :Issued: 2001 Sep 04 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 247 Issued at 2200Z on 04 Sep 2001 IA. Analysis of Solar Active Regions and Activity from 03/2100Z to 04/2100Z: Solar activity was moderate. A gradual rise in X-rays began at around 04/1000Z and continued through the end of this period. Since 04/1500Z, the X-ray baseline ranged from C4 - C8 with occasional fluctuations to the M1 level. Development within regions near the SE limb, the SW limb and within Region 9601 (N13W22) are the likely sources of the enhanced X-rays. Region 9606 (S17E45) produced an impulsive M1/1n at 04/2017Z. Region 9601, at almost 800 millionths of white light area is moderately complex and the largest region on the visible disk. Several plage fluctuations were observed in this region, but only minor C-class flareS were observed. The two M-class flares observed yesterday at 03/1545Z and 03/1841Z were likely associated with CMEs off the SE limb. New region 9607 (S16E68) was numbered today. IB. Solar Activity Forecast: Solar activity is expected to be at moderate to high levels. New regions near the SE limb and developing regions near the SW limb have potential for isolated M-class flares. Region 9601 also has potential for M-class flares. IIA. Geophysical Activity Summary 03/2100Z to 04/2100Z: The geomagnetic field was mostly at unsettled to active levels. A high speed coronal hole stream and possibly some weak CME effects are producing the disturbed conditions. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to return to quiet to unsettled conditions by the end of day one and persist through days two and three. III. Event Probabilities 05 Sep-07 Sep Class M 70/70/70 Class X 15/15/15 Proton 15/15/15 PCAF yellow IV. Penticton 10.7 cm Flux Observed 04 Sep 218 Predicted 05 Sep-07 Sep 210/210/205 90 Day Mean 04 Sep 158 V. Geomagnetic A Indices Observed Afr/Ap 03 Sep 012/017 Estimated Afr/Ap 04 Sep 015/018 Predicted Afr/Ap 05 Sep-07 Sep 010/012-010/010-010/010 VI. Geomagnetic Activity Probabilities 05 Sep-07 Sep A. Middle Latitudes Active 30/20/20 Minor storm 10/05/05 Major-severe storm 01/01/01 B. High Latitudes Active 40/25/25 Minor storm 15/05/05 Major-severe storm 05/01/01