:Product: 20040329RSGA.txt :Issued: 2004 Mar 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 089 Issued at 2200Z on 29 Mar 2004 IA. Analysis of Solar Active Regions and Activity from 28/2100Z to 29/2100Z: Solar activity was low. Region 582 (N14E18) produced several C-class flares today. The largest was a C5/Sf at 1551 UTC. The region dominates the solar disk in size and complexity and became more active during the past 24 hours. The region appears to be growing slowly. The only other region producing flares was 587 (S12E63) which managed to produce two B-class events. All the other regions on the disk were quiet and stable. A CME was observed by LASCO off the southwest limb around 0040 UTC, but the lack of corresponding disk signatures suggests that the source was on the back side. IB. Solar Activity Forecast: Solar activity is expected to be mostly low. There is a chance, however, for an isolated M-class flare from Region 582 during the next three days (30 March - 1 April). IIA. Geophysical Activity Summary 28/2100Z to 29/2100Z: The geomagnetic field was mostly quiet to unsettled, although there was one active period from 0300-0600 UTC. Solar wind data show a declining high speed stream with velocities slowly decreasing over the past 24 hours. The interplanetary magnetic field shows weak fluctuations in Bz, ranging from -3 nT to +3 nT. The greater than 2 MeV electron flux was high during the past 24 hours. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be unsettled with a slight chance for an active period during the next 24 hours (30 March). Conditions should decline to quiet to unsettled for the second and third days (31 March - 1 April) as the solar wind returns to nominal conditions. III. Event Probabilities 30 Mar-01 Apr Class M 35/35/35 Class X 05/05/05 Proton 05/05/05 PCAF green IV. Penticton 10.7 cm Flux Observed 29 Mar 129 Predicted 30 Mar-01 Apr 130/130/135 90 Day Mean 29 Mar 111 V. Geomagnetic A Indices Observed Afr/Ap 28 Mar 012/017 Estimated Afr/Ap 29 Mar 012/013 Predicted Afr/Ap 30 Mar-01 Apr 012/012-010/008-005/008 VI. Geomagnetic Activity Probabilities 30 Mar-01 Apr A. Middle Latitudes Active 30/25/20 Minor storm 20/15/10 Major-severe storm 05/05/05 B. High Latitudes Active 30/25/20 Minor storm 25/20/15 Major-severe storm 10/05/05