:Product: 20040408RSGA.txt :Issued: 2004 Apr 08 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 099 Issued at 2200Z on 08 Apr 2004 IA. Analysis of Solar Active Regions and Activity from 07/2100Z to 08/2100Z: Solar activity was low. Region 588 (S16W13) produced a C7/Sf flare at 08/1019Z. This event had an associated tenflare (190 sfu) and a full halo CME on LASCO imagery. No significant changes were observed in Region 588, which maintains a reverse polarity beta magnetic configuration. Coronal mass ejections were also observed to originate from behind the northwest limb. The first of these CMEs occurred at 08/0148Z and had an associated Type II radio sweep (709 km/s). A long duration x-ray enhancement accompanied the second CME at around 08/1900Z. No other significant changes or activity were observed. IB. Solar Activity Forecast: Solar activity is expected to continue at low levels. Region 588 is expected to produce occasional C-class activity. IIA. Geophysical Activity Summary 07/2100Z to 08/2100Z: The geomagnetic field was mostly quiet to active with isolated minor storm periods during local nighttime hours. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to range from quiet to minor storming. There has been no obvious transient passage at ACE yet from the full halo CME observed on LASCO imagery on 6 April. Occasional minor storm periods are expected in the next 24 hours from this CME. Another full halo CME was observed today and is expected to produce active to minor storm periods on 11 April. III. Event Probabilities 09 Apr-11 Apr Class M 15/15/10 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 08 Apr 094 Predicted 09 Apr-11 Apr 095/095/095 90 Day Mean 08 Apr 110 V. Geomagnetic A Indices Observed Afr/Ap 07 Apr 007/010 Estimated Afr/Ap 08 Apr 022/030 Predicted Afr/Ap 09 Apr-11 Apr 020/030-015/020-020/030 VI. Geomagnetic Activity Probabilities 09 Apr-11 Apr A. Middle Latitudes Active 40/30/40 Minor storm 30/20/30 Major-severe storm 15/10/15 B. High Latitudes Active 45/40/45 Minor storm 35/30/35 Major-severe storm 20/15/20