:Product: 20010525RSGA.txt :Issued: 2001 May 25 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 145 Issued at 2200Z on 25 May 2001 IA. Analysis of Solar Active Regions and Activity from 24/2100Z to 25/2100Z: Solar activity was low. The largest flare of the past day was a C5 at 25/1937 UTC which occurred in conjunction with optical flares in Regions 9463 (N08W23) and 9468 (N07E12). Both of these sunspot groups were responsible for other, smaller x-ray flares as well. Other disk regions were relatively quiet. IB. Solar Activity Forecast: Solar activity is expected to be low to moderate. Additional C-class flares are likely and an isolated M-class flare is possible. Regions 9463 and 9468 are the most probable sources of activity. IIA. Geophysical Activity Summary 24/2100Z to 25/2100Z: The geomagnetic field ranged from quiet to active levels. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet to unsettled. III. Event Probabilities 26 May-28 May Class M 30/30/30 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 25 May 162 Predicted 26 May-28 May 160/160/155 90 Day Mean 25 May 168 V. Geomagnetic A Indices Observed Afr/Ap 24 May 007/009 Estimated Afr/Ap 25 May 008/008 Predicted Afr/Ap 26 May-28 May 008/008-015/015-010/018 VI. Geomagnetic Activity Probabilities 26 May-28 May A. Middle Latitudes Active 10/15/15 Minor storm 01/05/05 Major-severe storm 01/01/01 B. High Latitudes Active 10/20/15 Minor storm 05/05/05 Major-severe storm 01/02/02