:Product: 0921RSGA.txt :Issued: 2010 Sep 21 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 264 Issued at 2200Z on 21 Sep 2010 IA. Analysis of Solar Active Regions and Activity from 20/2100Z to 21/2100Z: Solar activity has been at low levels for the past 24 hours. New Region 1109 (N19E75) was numbered today as it rotated onto the visible disk. Region 1109 produced a few C-class events, the largest was a C1 flare at 21/0738Z. Region 1108 (S30E14) decreased in areal coverage and sunspot number but has retained its bi-polar magnetic classification. Region 1106 (S22W69) has continued to decay and now has an alpha magnetic classification. IB. Solar Activity Forecast: Solar activity is expected to be at low levels with a slight chance for M-class activity for the next three days (22-24 September). IIA. Geophysical Activity Summary 20/2100Z to 21/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at unsettled to active levels on days one and two (22-23 September) due to a recurrent coronal hole high-speed stream. Mostly unsettled levels are expected on day three (24 September). III. Event Probabilities 22 Sep-24 Sep Class M 10/10/10 Class X 01/01/01 Proton 01/01/01 PCAF Green IV. Penticton 10.7 cm Flux Observed 21 Sep 085 Predicted 22 Sep-24 Sep 088/088/088 90 Day Mean 21 Sep 079 V. Geomagnetic A Indices Observed Afr/Ap 20 Sep 003/004 Estimated Afr/Ap 21 Sep 006/008 Predicted Afr/Ap 22 Sep-24 Sep 015/018-015/018-012/012 VI. Geomagnetic Activity Probabilities 22 Sep-24 Sep A. Middle Latitudes Active 35/35/25 Minor storm 05/05/01 Major-severe storm 01/01/01 B. High Latitudes Active 35/35/25 Minor storm 10/10/01 Major-severe storm 01/01/01