NOAA SEC Report of Solar-Geophysical Activity 30 Apr 2001
:Product: Report of Solar-Geophysical Activity :Issued: 2001 Apr 30 2200 UT # 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 120 Issued at 2200Z on 30 Apr 2001 IA. Analysis of Solar Active Regions and Activity from 29/2100Z to 30/2100Z: Solar activity has been low. Region 9445 (N24E48) produced a C5/Sf flare at 30/0721Z, and numerous lesser C-class flares throughout the day. Region 9333 (N17W74) was also a source of C-class activity. Regions 9445 and 9441 (N07W04) both exhibited moderate growth in areal coverage, while Region 9433 has shown some signs of decay as it approaches the west limb. New Region 9447 (N12E15) was numbered today. IB. Solar Activity Forecast: Solar activity is expected to be moderate, with a chance for a major flare event remaining for Region 9433 in particular. IIA. Geophysical Activity Summary 29/2100Z to 30/2100Z: The geomagnetic field has been quiet to unsettled. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be predominantly quiet to unsettled, with an increasing chance of active to minor storm conditions evolving toward the end of the three day period, due to a favorably positioned coronal hole. Any major flare activity from Region 9433 during the period would also carry a fair chance for an associated proton event. III. Event Probabilities 01 May-03 May Class M 70/70/60 Class X 15/15/10 Proton 15/15/10 PCAF Green IV. Penticton 10.7 cm Flux Observed 30 Apr 188 Predicted 01 May-03 May 185/180/175 90 Day Mean 30 Apr 168 V. Geomagnetic A Indices Observed Afr/Ap 29 Apr 011/015 Estimated Afr/Ap 30 Apr 004/010 Predicted Afr/Ap 01 May-03 May 010/010-010/012-010/015 VI. Geomagnetic Activity Probabilities 01 May-03 May A. Middle Latitudes Active 15/15/15 Minor storm 05/05/05 Major-severe storm 01/01/01 B. High Latitudes Active 20/20/20 Minor storm 10/10/15 Major-severe storm 01/01/01
