:Product: 1219RSGA.txt :Issued: 2009 Dec 19 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 353 Issued at 2200Z on 19 Dec 2009 IA. Analysis of Solar Active Regions and Activity from 18/2100Z to 19/2100Z: Solar activity was low by virtue of a single C2.9/Sf at 10/0014Z from Region 1035 (N30W56). Since this event, only B-class x-ray activity, with some weak, low frequency radio emissions have been observed from this region. Over the past 24 hours, the region decayed, both in areal coverage and spot number, but retained its beta magnetic configuration. Two new regions were numbered this period. Region 1036 (S29W19) emerged on the disk as a 3-spot beta group, while Region 1037 (N18E54) rotated onto the disk as a 2-spot beta group. Both regions have been quiet and stable. IB. Solar Activity Forecast: Solar activity is expected to be low for the next three days. There is a slight chance for an isolated M-class event from Region 1035. IIA. Geophysical Activity Summary 18/2100Z to 19/2100Z: The geomagnetic field has been quiet. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet to unsettled with a chance for isolated active periods on day one (20 December). This activity is in response to the expected arrival of the CME observed on 16 December. Days two and three (21 - 22 December) will see mostly quiet conditions. III. Event Probabilities 20 Dec-22 Dec Class M 10/10/05 Class X 01/01/01 Proton 01/01/01 PCAF Green IV. Penticton 10.7 cm Flux Observed 19 Dec 082 Predicted 20 Dec-22 Dec 082/082/080 90 Day Mean 19 Dec 074 V. Geomagnetic A Indices Observed Afr/Ap 18 Dec 002/002 Estimated Afr/Ap 19 Dec 002/005 Predicted Afr/Ap 20 Dec-22 Dec 015/015-007/008-005/005 VI. Geomagnetic Activity Probabilities 20 Dec-22 Dec A. Middle Latitudes Active 45/15/05 Minor storm 15/05/01 Major-severe storm 05/01/01 B. High Latitudes Active 50/15/05 Minor storm 20/10/01 Major-severe storm 10/01/01