:Product: 1213RSGA.txt :Issued: 2011 Dec 13 2200 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 347 Issued at 2200Z on 13 Dec 2011 IA. Analysis of Solar Active Regions and Activity from 12/2100Z to 13/2100Z: Solar activity was low. There were three, low-level C-class flares during the past 24 hours, all from Region 1367 (S18W89). Region 1367 showed signs of new flux emerging as it was rotating around the west limb. Region 1374 (S18E01) continues to be the largest group on the disk (140 millionths) and shows a very small delta configuration in the leader spot region, but was quiet and stable. Two erupting prominences which led to coronal mass ejections were observed: the first just entered the LASCO/C2 field of view at 12/1848Z, slightly west of the north pole and the second entered LASCO/C2 field of view at 13/0200Z off the southwest limb. Neither of these CMEs are expected to be geoeffective. IB. Solar Activity Forecast: Solar activity is expected to be low. IIA. Geophysical Activity Summary 12/2100Z to 13/2100Z: The geomagnetic field was mostly quiet. There was an interval of unsettled levels from 0900-1500Z at high latitudes. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet for day one (14 December). Quiet levels with a chance for some unsettled periods are expected for day two (15 December) due to a possible brief, glancing blow from an erupting prominence/CME that was observed on 11 December. Quiet levels are expected to prevail for the third day (16 December). III. Event Probabilities 14 Dec-16 Dec Class M 05/05/05 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 13 Dec 133 Predicted 14 Dec-16 Dec 133/132/130 90 Day Mean 13 Dec 146 V. Geomagnetic A Indices Observed Afr/Ap 12 Dec 004/004 Estimated Afr/Ap 13 Dec 003/004 Predicted Afr/Ap 14 Dec-16 Dec 005/005-007/008-005/005 VI. Geomagnetic Activity Probabilities 14 Dec-16 Dec A. Middle Latitudes Active 05/10/05 Minor storm 01/01/01 Major-severe storm 01/01/01 B. High Latitudes Active 15/15/15 Minor storm 10/15/10 Major-severe storm 05/10/05