:Product: 20010731RSGA.txt :Issued: 2001 Jul 31 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 212 Issued at 2200Z on 31 Jul 2001 IA. Analysis of Solar Active Regions and Activity from 30/2100Z to 31/2100Z: Solar activity remained low. Isolated B- and C-class subflares occurred. Region 9561 (S12E49) was the most active of the visible regions, but showed no significant changes during the period. A couple large filaments erupted from the south-central portion of the disk early in the period. New Region 9563 (N24E57) was numbered. IB. Solar Activity Forecast: Solar activity is expected to remain at low levels. IIA. Geophysical Activity Summary 30/2100Z to 31/2100Z: Geomagnetic field activity was at unsettled to active levels due to coronal hole effects. IIB. Geophysical Activity Forecast: Geomagnetic field activity is expected to be at quiet to active levels on the first day decreasing to quiet to unsettled levels for the remainder of the period. III. Event Probabilities 01 Aug-03 Aug Class M 20/20/20 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 31 Jul 117 Predicted 01 Aug-03 Aug 120/120/125 90 Day Mean 31 Jul 150 V. Geomagnetic A Indices Observed Afr/Ap 30 Jul 008/009 Estimated Afr/Ap 31 Jul 018/023 Predicted Afr/Ap 01 Aug-03 Aug 012/015-008/010-008/010 VI. Geomagnetic Activity Probabilities 01 Aug-03 Aug A. Middle Latitudes Active 30/20/20 Minor storm 15/10/10 Major-severe storm 05/01/01 B. High Latitudes Active 35/25/25 Minor storm 20/15/15 Major-severe storm 05/01/01