:Product: 20010124RSGA.txt :Issued: 2001 Jan 24 2200 UTC # 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 024 Issued at 2200Z on 24 Jan 2001 IA. Analysis of Solar Active Regions and Activity from 23/2100Z to 24/2100Z: Solar activity has been moderate during the past 24 hours. An increase in flare production and x-ray background began yesterday around 1800Z, leading to frequent C-class flares and one M-class flare during the past 24 hours. Today's largest event was an M1/2f at 1447Z from Region 9311 (N06W76). Most of the new activity was from Region 9311 although Region 9313 (S07W12) and Region 9321 (S06E31) also contributed to some of the activity. Regions 9313 and 9321 appear to be growing slowly. IB. Solar Activity Forecast: Solar activity is expected to be moderate tomorrow, with a fair-to-good chance for another M-class event from Region 9311. A decrease in activity and background levels is anticipated on the second and third days, however, with the departure of Region 9311 from the solar disk. IIA. Geophysical Activity Summary 23/2100Z to 24/2100Z: The geomagnetic field was mostly unsettled to active during the past 24 hours. There was a minor storm period at high latitudes from 1200-1500Z. Solar wind signatures showed characteristics of swept up flow, and perhaps a portion of transient flow, but there was no indication of passing through the main part of the driver. Greater than 10 MeV protons remained enhanced but were beginning to decline near day's end. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be unsettled to slightly active during the next 12-24 hours. A decrease to mostly unsettled is expected for the second and third days. III. Event Probabilities 25 Jan-27 Jan Class M 60/40/20 Class X 10/05/05 Proton 15/10/05 PCAF green IV. Penticton 10.7 cm Flux Observed 24 Jan Predicted 25 Jan-27 Jan 175/170/165 90 Day Mean 24 Jan 174 V. Geomagnetic A Indices Observed Afr/Ap 23 Jan 007/011 Estimated Afr/Ap 24 Jan 018/020 Predicted Afr/Ap 25 Jan-27 Jan 015/015-012/012-010/012 VI. Geomagnetic Activity Probabilities 25 Jan-27 Jan A. Middle Latitudes Active 30/25/20 Minor storm 20/15/10 Major-severe storm 05/05/05 B. High Latitudes Active 30/25/20 Minor storm 20/15/10 Major-severe storm 10/05/05