:Product: 1222RSGA.txt :Issued: 2007 Dec 22 2203 UTC # Prepared jointly by the U.S. Dept. of Commerce, NOAA, # Space Weather Prediction Center and the U.S. Air Force. # Joint USAF/NOAA Report of Solar and Geophysical Activity SDF Number 356 Issued at 2200Z on 22 Dec 2007 IA. Analysis of Solar Active Regions and Activity from 21/2100Z to 22/2100Z: Solar activity was very low. The visible disk remains spotless. IB. Solar Activity Forecast: Solar activity is expected to be very low. IIA. Geophysical Activity Summary 21/2100Z to 22/2100Z: The geomagnetic field was quiet to unsettled. Observations at ACE showed solar wind velocities varied between 571-652 km/sec through the forecast period. The greater than 2 MeV electron flux at geosynchronous orbit remained at high levels. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet to unsettled for the next three days (23-25 December). Isolated active conditions are possible at high latitudes on 23 December. III. Event Probabilities 23 Dec-25 Dec Class M 01/01/01 Class X 01/01/01 Proton 01/01/01 PCAF Green IV. Penticton 10.7 cm Flux Observed 22 Dec 072 Predicted 23 Dec-25 Dec 070/070/070 90 Day Mean 22 Dec 071 V. Geomagnetic A Indices Observed Afr/Ap 21 Dec 009/011 Estimated Afr/Ap 22 Dec 007/010 Predicted Afr/Ap 23 Dec-25 Dec 006/008-005/005-005/005 VI. Geomagnetic Activity Probabilities 23 Dec-25 Dec A. Middle Latitudes Active 15/15/15 Minor storm 01/01/01 Major-severe storm 01/01/01 B. High Latitudes Active 20/15/15 Minor storm 05/05/05 Major-severe storm 01/01/01