:Product: 20041216RSGA.txt :Issued: 2004 Dec 16 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 351 Issued at 2200Z on 16 Dec 2004 IA. Analysis of Solar Active Regions and Activity from 15/2100Z to 16/2100Z: Solar activity was very low. Region 710 (S06W61) was responsible for a few B-class flares. A full halo CME observed on LASCO imagery late on 15 December was determined to be a farside event. IB. Solar Activity Forecast: Solar activity is expected to be very low to low. A new region rotating on the southeast limb may slightly increase activity levels. IIA. Geophysical Activity Summary 15/2100Z to 16/2100Z: The geomagnetic field was quiet to unsettled with isolated active levels late in the period. A gradual increase in solar wind speed began about 16/0500Z. Speed increased from near 350 km/s to 600 km/s by the end of the day. This is likely the onset of a recurrent high speed stream. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet to active with minor storm periods at high latitudes on 17 and 18 December. Expect quiet to unsettled levels with isolated active conditions on 19 December as the high speed coronal hole stream subsides. III. Event Probabilities 17 Dec-19 Dec Class M 05/05/05 Class X 01/01/01 Proton 01/01/01 PCAF Green IV. Penticton 10.7 cm Flux Observed 16 Dec 090 Predicted 17 Dec-19 Dec 090/090/090 90 Day Mean 16 Dec 104 V. Geomagnetic A Indices Observed Afr/Ap 15 Dec 003/006 Estimated Afr/Ap 16 Dec 008/010 Predicted Afr/Ap 17 Dec-19 Dec 012/020-008/015-006/008 VI. Geomagnetic Activity Probabilities 17 Dec-19 Dec A. Middle Latitudes Active 30/20/15 Minor storm 15/10/10 Major-severe storm 05/01/01 B. High Latitudes Active 35/25/25 Minor storm 20/15/10 Major-severe storm 10/05/05