:Product: 20040519RSGA.txt :Issued: 2004 May 19 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 140 Issued at 2200Z on 19 May 2004 IA. Analysis of Solar Active Regions and Activity from 18/2100Z to 19/2100Z: Solar activity was low. Two small C-class flares occurred in an unnumbered region rotating onto the disk near SE10. Regions currently on the visible disk have been relatively quiet with only a few B-class flares observed. IB. Solar Activity Forecast: Solar activity is expected to be low. Sunspots associated with the new region at the southeast limb are expected to rotate into view within the next 24 hours. B and C-class flares are most likely to occur in this new region. IIA. Geophysical Activity Summary 18/2100Z to 19/2100Z: The geomagnetic field was mostly quiet to unsettled. An isolated active period occurred at some locations at 19/1500-1800 UTC. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet to unsettled. NOTE: The ACE spacecraft orbit will bring ACE nearly in line with the Sun from about May 30 to June 2, 2004. During that time solar radio noise is expected to interfere with spacecraft telemetry resulting in the loss of solar wind plasma, magnetic field, and particle data. III. Event Probabilities 20 May-22 May Class M 30/30/30 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 19 May 109 Predicted 20 May-22 May 110/110/100 90 Day Mean 19 May 105 V. Geomagnetic A Indices Observed Afr/Ap 18 May 004/004 Estimated Afr/Ap 19 May 008/010 Predicted Afr/Ap 20 May-22 May 008/015-008/010-008/015 VI. Geomagnetic Activity Probabilities 20 May-22 May A. Middle Latitudes Active 15/15/15 Minor storm 05/05/05 Major-severe storm 01/01/01 B. High Latitudes Active 30/30/30 Minor storm 10/10/10 Major-severe storm 05/05/05