:Product: 0419RSGA.txt :Issued: 2010 Apr 19 2201 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 109 Issued at 2200Z on 19 Apr 2010 IA. Analysis of Solar Active Regions and Activity from 18/2100Z to 19/2100Z: Solar activity was very low. No flares were observed during the last 24 hours. The visible disk remained spotless. A CME was noted on SOHO and STEREO imagery on the southwest limb at approximately 18/2300Z. The source of this activity is unknown, however, it may be related to a prominence located just behind the southwest limb. In addition, a second CME was observed at 19/1754Z on the SOHO C2 image. This activity is likely associated with a filament that lifted off the NW limb (approx. N40W85). IB. Solar Activity Forecast: Solar activity is expected to remain very low for the next three days (20-22 April). IIA. Geophysical Activity Summary 18/2100Z to 19/2100Z: The geomagnetic field was quiet during the last 24 hours. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to remain quiet for day one (20 April). Quiet to unsettled levels with isolated active periods are expected for days two and three (21-22 April). Activity is expected due to possible effects from a weak CME observed on 15 April and two coronal hole high speed streams rotating into a geoeffective position. III. Event Probabilities 20 Apr-22 Apr Class M 01/01/01 Class X 01/01/01 Proton 01/01/01 PCAF Green IV. Penticton 10.7 cm Flux Observed 19 Apr 075 Predicted 20 Apr-22 Apr 079/080/082 90 Day Mean 19 Apr 082 V. Geomagnetic A Indices Observed Afr/Ap 18 Apr 001/002 Estimated Afr/Ap 19 Apr 004/004 Predicted Afr/Ap 20 Apr-22 Apr 005/005-010/010-012/012 VI. Geomagnetic Activity Probabilities 20 Apr-22 Apr A. Middle Latitudes Active 05/15/25 Minor storm 01/05/10 Major-severe storm 01/01/05 B. High Latitudes Active 10/25/30 Minor storm 05/10/15 Major-severe storm 01/05/05