NOAA SEC Report of Solar-Geophysical Activity 18 Dec 2001
:Product: Report of Solar-Geophysical Activity :Issued: 2001 Dec 18 2200 UT # Prepared jointly by the U.S. Dept. of Commerce, NOAA, #Space Environment Center and the U.S. Air Force. # Joint USAF/NOAA Report of Solar and Geophysical Activity SDF Number 352 Issued at 2200Z on 18 Dec 2001 IA. Analysis of Solar Active Regions and Activity from 17/2100Z to 18/2100Z: Solar activity was at low levels. Only isolated C-class events were observed during the period. Three regions have moderately complex beta-gamma magnetic classification: 9733 (N13W62), 9738 (S18W12), and 9742 (N10E37). Regions 9738 and 9742 are showing signs of increased activity and growth, while 9733 is steadily decaying. Region 9733 will rotate over the west limb on 21 December. One new region was numbered: 9745 (N18E60). IB. Solar Activity Forecast: Solar activity is expected to be at low to moderate levels. Regions 9738 and 9742 are expected to continue to grow in size and complexity and should produce increased levels of activity. Region 9733 continues to retain a slight chance of producing a major flare before it transits over the western limb. IIA. Geophysical Activity Summary 17/2100Z to 18/2100Z: The geomagnetic field was at quiet to unsettled conditions. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to continue to be at quiet to unsettled levels. III. Event Probabilities 19 Dec-21 Dec Class M 75/75/75 Class X 10/10/10 Proton 10/10/10 PCAF green IV. Penticton 10.7 cm Flux Observed 18 Dec 212 Predicted 19 Dec-21 Dec 200/200/195 90 Day Mean 18 Dec 219 V. Geomagnetic A Indices Observed Afr/Ap 17 Dec 009/015 Estimated Afr/Ap 18 Dec 008/008 Predicted Afr/Ap 19 Dec-21 Dec 008/008-008/008-008/008 VI. Geomagnetic Activity Probabilities 19 Dec-21 Dec A. Middle Latitudes Active 20/20/20 Minor storm 05/05/05 Major-severe storm 01/01/01 B. High Latitudes Active 25/25/25 Minor storm 10/10/10 Major-severe storm 01/01/01
