NOAA SEC Report of Solar-Geophysical Activity 25 Dec 2001
:Product: Report of Solar-Geophysical Activity :Issued: 2001 Dec 25 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 359 Issued at 2200Z on 25 Dec 2001 IA. Analysis of Solar Active Regions and Activity from 24/2100Z to 25/2100Z: Solar activity was moderate. Region 9754 (S09E38) was the most active area producing two M1 flares this past day. This sunspot group is a growing E-type region developing increased magnetic complexity. Region 9742 (N12W57) remains the largest sunspot group on the disk with area in excess of 1000 millionths. However this region does not appear to have significant magnetic complexity and has not produced major activity. New Region 9755 (S05E64) rotated onto the disk. IB. Solar Activity Forecast: Solar activity is expected to be moderate. M-class flares are possible in Regions 9742, 9748, and 9754. IIA. Geophysical Activity Summary 24/2100Z to 25/2100Z: The geomagnetic field was quiet to unsettled. The high-speed coronal hole stream apparent yesterday has passed and solar wind parameters have returned to nominal values. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet to unsettled. III. Event Probabilities 26 Dec-28 Dec Class M 75/75/75 Class X 10/10/10 Proton 10/10/10 PCAF green IV. Penticton 10.7 cm Flux Observed 25 Dec 259 Predicted 26 Dec-28 Dec 260/260/255 90 Day Mean 25 Dec 217 V. Geomagnetic A Indices Observed Afr/Ap 24 Dec 013/019 Estimated Afr/Ap 25 Dec 010/010 Predicted Afr/Ap 26 Dec-28 Dec 010/010-008/010-008/008 VI. Geomagnetic Activity Probabilities 26 Dec-28 Dec A. Middle Latitudes Active 10/10/10 Minor storm 05/05/05 Major-severe storm 01/01/01 B. High Latitudes Active 20/20/20 Minor storm 10/10/10 Major-severe storm 05/05/05
