:Product: 20020110RSGA.txt :Issued: 2002 Jan 10 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 010 Issued at 2200Z on 10 Jan 2002 IA. Analysis of Solar Active Regions and Activity from 09/2100Z to 10/2100Z: Solar activity was low. Region 9773 (N14W17) belied its ominous appearance in white light and h-alpha by producing just C-class events in the past 24 hours. A C7/Sf at 1018 UTC was the largest event, although the x-ray background from GOES was enhanced throughout the day. The region measures more than 500 millionths in white light, and retains a significant degree of magnetic complexity. Elsewhere, Region 9778 (S17E45) grew in most parameters and produced occasional subflares. IB. Solar Activity Forecast: Solar activity is expected to be moderate. Region 9773 is capable of M class activity. IIA. Geophysical Activity Summary 09/2100Z to 10/2100Z: The geomagnetic field varied from quiet to minor storm levels. A high speed solar wind stream began to impact the magnetosphere early in the period, with solar wind speeds increasing from 350 km/s to more than 600 km/s. In addition, there have been intervals where the interplanetary magnetic field has been near 20 nT southward, further fueling the disturbance. An enhancement in the greater than 10 MeV protons at GOES began around 0700 UTC. The flux attained event level (10 pfu at greater than 10 MeV) at 2045 UTC. This increase may be associated with east limb activity that occurred late on January 8. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at active to minor storm levels. The current disturbance should persist for the next 24-48 hours. The greater than 10 MeV proton event is likely to slowly decay. III. Event Probabilities 11 Jan-13 Jan Class M 75/75/75 Class X 25/25/25 Proton 75/50/25 PCAF yellow IV. Penticton 10.7 cm Flux Observed 10 Jan 225 Predicted 11 Jan-13 Jan 230/235/240 90 Day Mean 10 Jan 223 V. Geomagnetic A Indices Observed Afr/Ap 09 Jan 002/003 Estimated Afr/Ap 10 Jan 015/023 Predicted Afr/Ap 11 Jan-13 Jan 020/030-015/020-015/015 VI. Geomagnetic Activity Probabilities 11 Jan-13 Jan A. Middle Latitudes Active 50/50/50 Minor storm 30/30/30 Major-severe storm 10/10/10 B. High Latitudes Active 30/40/40 Minor storm 50/40/40 Major-severe storm 10/10/05