:Product: 20041204RSGA.txt :Issued: 2004 Dec 04 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 339 Issued at 2200Z on 04 Dec 2004 IA. Analysis of Solar Active Regions and Activity from 03/2100Z to 04/2100Z: Solar activity was very low. Only small B-class flares occurred in the past 24 hours. Both Regions 707 (S13W64) and 708 (N09W26) are slowly decaying. IB. Solar Activity Forecast: Solar activity is expected to be very low to low. Small flares could occur in Regions 707 and 708. An isolated M-class flare is possible in 708 but will become less likely as the region decays. IIA. Geophysical Activity Summary 03/2100Z to 04/2100Z: The geomagnetic field was quiet. The solar wind observed by ACE RTSW over the past 24 hours has been characterized by weak IMF and unusually low density and speed. The greater than 2 MeV electron flux at geosynchronous orbit was high. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to remain quiet until the arrival of the CME associated with the M1 flare on 03 Dec. Arrival is still expected before mid-day on 05 Dec. Geomagnetic storm conditions are possible on 05 Dec as a result of the CME and the influence of an anticipated high-speed coronal hole stream in the same time period. III. Event Probabilities 05 Dec-07 Dec Class M 20/15/10 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 04 Dec 097 Predicted 05 Dec-07 Dec 095/090/090 90 Day Mean 04 Dec 108 V. Geomagnetic A Indices Observed Afr/Ap 03 Dec 001/003 Estimated Afr/Ap 04 Dec 005/005 Predicted Afr/Ap 05 Dec-07 Dec 035/040-015/020-012/015 VI. Geomagnetic Activity Probabilities 05 Dec-07 Dec A. Middle Latitudes Active 60/30/20 Minor storm 20/10/05 Major-severe storm 10/05/01 B. High Latitudes Active 25/50/25 Minor storm 50/20/10 Major-severe storm 25/10/01