:Product: 20010429RSGA.txt :Issued: 2001 Apr 29 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 119 Issued at 2200Z on 29 Apr 2001 IA. Analysis of Solar Active Regions and Activity from 28/2100Z to 29/2100Z: Solar activity remained low. Region 9433 (N18W63) produced isolated C-class subflares as it continued to show gradual decay in its lead and intermediate spots. However, no significant changes occurred within its trailer spots, where a magnetic delta configuration persisted. Region 9441 (N07E11) continued a gradual growth phase, but remained simply structured. Region 9444 (S11E52) showed minor spot and penumbral development. Region 9445 (N24E61) also exhibited minor spot and penumbral development and produced isolated C-class subflares late in the period. New Region 9446 (S05W22) was numbered. IB. Solar Activity Forecast: Solar activity is expected to be at moderate to high levels. Region 9433 is expected to produce isolated low-level M-class flares during the period. It may also produce an isolated major flare before crossing the west limb on 02 May. IIA. Geophysical Activity Summary 28/2100Z to 29/2100Z: Geomagnetic field activity ranged from quiet to active levels. The geomagnetic field disturbance that began yesterday subsided to quiet to unsettled levels after 29/0600 UTC. IIB. Geophysical Activity Forecast: Geomagnetic field activity is expected to be at quiet to unsettled levels during the period. Region 9433 could produce a proton flare before crossing the west limb on 02 May. III. Event Probabilities 30 Apr-02 May Class M 70/70/70 Class X 20/20/20 Proton 20/20/20 PCAF Green IV. Penticton 10.7 cm Flux Observed 29 Apr 192 Predicted 30 Apr-02 May 190/185/180 90 Day Mean 29 Apr 168 V. Geomagnetic A Indices Observed Afr/Ap 28 Apr 034/028 Estimated Afr/Ap 29 Apr 015/015 Predicted Afr/Ap 30 Apr-02 May 010/010-010/010-010/012 VI. Geomagnetic Activity Probabilities 30 Apr-02 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 10/10/10 Major-severe storm 01/01/01