:Product: 20010331RSGA.txt :Issued: 2001 Mar 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 090 Issued at 2200Z on 31 Mar 2001 IA. Analysis of Solar Active Regions and Activity from 30/2100Z to 31/2100Z: Solar activity has been moderate with the only significant activity a Class M event in Region 9393 (N17 W43) at 31/1100 UT. Active Region 9393 remains as threatening as before. IB. Solar Activity Forecast: Solar activity is expected to remain moderate to high with continued expectation of another major flare in Region 9393. IIA. Geophysical Activity Summary 30/2100Z to 31/2100Z: The geomagnetic field has been at severe storm levels. A shock passed the ACE spacecraft at 31/0023 UT and subsequently reached Earth's magnetic field at 31/0051. The storm developed after that time and reached maximum intensity after 31/0900 UT. It has continued into the later hours of the UT days. Dynamic auroral displays were reported across the United States with especially dynamic displays reported in Arizona, west Texas and California. The solar proton event that began at 29/1000 UT was declared over at 01/0600 UT. IIB. Geophysical Activity Forecast: The geomagnetic storm in progress is expected to continue into tomorrow before declining to less disturbed levels III. Event Probabilities 01 Apr-03 Apr Class M 80/80/80 Class X 35/35/35 Proton 30/30/30 PCAF Green IV. Penticton 10.7 cm Flux Observed 31 Mar 246 Predicted 01 Apr-03 Apr 240/230/220 90 Day Mean 31 Mar 164 V. Geomagnetic A Indices Observed Afr/Ap 30 Mar 008/010 Estimated Afr/Ap 31 Mar 140/150 Predicted Afr/Ap 01 Apr-03 Apr 065/070-030/035-020/025 VI. Geomagnetic Activity Probabilities 01 Apr-03 Apr A. Middle Latitudes Active 20/50/40 Minor storm 25/10/05 Major-severe storm 35/15/05 B. High Latitudes Active 27/27/27 Minor storm 30/30/30 Major-severe storm 25/15/12