:Product: 20011108RSGA.txt :Issued: 2001 Nov 08 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 312 Issued at 2200Z on 08 Nov 2001 IA. Analysis of Solar Active Regions and Activity from 07/2100Z to 08/2100Z: Activity remained at high levels. Region 9687 (S19W18) produced an impulsive M9/1n flare at 08/0704 UTC associated with a 460 SFU Tenflare and a Type II radio sweep (est. velocity 818 km/sec). It also produced an impulsive C8/Sn flare at 08/1904 UTC, possibly associated with Type II (est. velocity 928 km/sec) and Type IV radio sweeps. This region showed no significant changes prior to or following the major flare, but it remained moderate in size and magnetic complexity, mainly due to the presence of a small delta magnetic configuration within its interior spots. Region 9690 (S13E31) remained the most impressive sunspot group on the disk with an area exceeding 1000 millions of the visible disk. It produced occasional flares including three M-class, the largest of which was an M4/2f at 08/1535 UTC. This region continued to increase in spot count, area, and magnetic complexity with strong magnetic gradients and a magnetic delta configuration within its leader spots. Region 9684 (N06W82), which was responsible for the X1/3b flare on 04 November, began a relatively quiet west limb passage. The remaining regions were unimpressive in most respects. No new regions were assigned today. IB. Solar Activity Forecast: Activity is expected to be at moderate to high levels. M-class flares are expected. Regions 9690 and 9687 have the potential for major flare production. IIA. Geophysical Activity Summary 07/2100Z to 08/2100Z: Geomagnetic field activity was at quiet to unsettled levels. The greater than 10 MeV proton event at geosynchronous orbit continued. The greater than 10 MeV flux was 35 PFU and gradually decreasing at the close of the period. This event began at 04/1705 UTC and reached a maximum of 31,700 PFU at 06/0215 UTC. The polar cap absorption event that began on 04 November ended today. IIB. Geophysical Activity Forecast: Geomagnetic field activity is expected to be at quiet to unsettled levels during the first day increasing to quiet to active levels on the last two days. The greater than 10 MeV proton event is expected to end early on 09 November. There will be a slight chance for another proton flare during the period. III. Event Probabilities 09 Nov-11 Nov Class M 90/90/90 Class X 30/30/30 Proton 75/20/20 PCAF yellow IV. Penticton 10.7 cm Flux Observed 08 Nov 248 Predicted 09 Nov-11 Nov 245/250/250 90 Day Mean 08 Nov 210 V. Geomagnetic A Indices Observed Afr/Ap 07 Nov 011/015 Estimated Afr/Ap 08 Nov 006/008 Predicted Afr/Ap 09 Nov-11 Nov 008/010-015/015-015/015 VI. Geomagnetic Activity Probabilities 09 Nov-11 Nov A. Middle Latitudes Active 25/40/40 Minor storm 10/15/15 Major-severe storm 05/05/05 B. High Latitudes Active 25/40/40 Minor storm 10/15/15 Major-severe storm 05/05/05