:Product: 20010527RSGA.txt :Issued: 2001 May 27 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 147 Issued at 2200Z on 27 May 2001 IA. Analysis of Solar Active Regions and Activity from 26/2100Z to 27/2100Z: Solar activity was very low. All disk regions have been relatively inactive. Region 9463 (N08W51), the largest sunspot group presently on the disk, and Region 9468 (N06W16) have decayed since yesterday. New Regions 9476 (S22W68), 9477 (S16E20), and 9478 (N14E15) were numbered. IB. Solar Activity Forecast: Solar activity is expected to be low. IIA. Geophysical Activity Summary 26/2100Z to 27/2100Z: The geomagnetic field ranged from quiet to active levels. An SI was observed at the Boulder ground magnetometer at 27/1456 UTC following a shock observed in the solar wind at ACE at 27/1418 UTC. Timing of the structure seems consistent with the M1/1N/Type II event which occurred on 24 May. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet to unsettled with an occasional active period during the passage of the CME. Quiet to unsettled conditions are expected for the remainder of the forecast period. III. Event Probabilities 28 May-30 May Class M 20/20/20 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 27 May 147 Predicted 28 May-30 May 140/140/135 90 Day Mean 27 May 169 V. Geomagnetic A Indices Observed Afr/Ap 26 May 006/008 Estimated Afr/Ap 27 May 012/015 Predicted Afr/Ap 28 May-30 May 010/012-008/010-008/008 VI. Geomagnetic Activity Probabilities 28 May-30 May A. Middle Latitudes Active 15/15/15 Minor storm 05/05/05 Major-severe storm 01/01/01 B. High Latitudes Active 15/15/15 Minor storm 05/05/05 Major-severe storm 01/01/01