:Product: 20040128RSGA.txt :Issued: 2004 Jan 28 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 028 Issued at 2200Z on 28 Jan 2004 IA. Analysis of Solar Active Regions and Activity from 27/2100Z to 28/2100Z: Solar activity was very low. There were no flares in the past 24 hours. The solar disk was devoid of spots for most of the day, but towards the end of the period there was evidence for a new active region (or regions) rotating on the disk at latitudes S10-S15, near the location where old Region 536 would be expected. IB. Solar Activity Forecast: Solar activity is expected to be very low. There should be a slow rise in background levels as the new active region (or regions) rotate into view. IIA. Geophysical Activity Summary 27/2100Z to 28/2100Z: The geomagnetic field ranged from unsettled to minor storm levels. Solar wind velocity showed a gradual increase beginning around 0100 UTC, and this was accompanied by frequent fluctuations in the interplanetary Bz component in the range of about -7 nT to +7 nT. These signatures together with a consistent 'away' polarity in the solar phi angle all suggest that the activity was driven by favorably positioned positive polarity coronal hole. The greater than 2 MeV electron fluxes were at high levels during the past 24 hours. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be unsettled with occasional active periods for the next two days (29-30 January). An increase to unsettled to active is expected on the third day (31 January) as another coronal hole rotates into favorable position. III. Event Probabilities 29 Jan-31 Jan Class M 01/01/01 Class X 01/01/01 Proton 01/01/01 PCAF Green IV. Penticton 10.7 cm Flux Observed 28 Jan 089 Predicted 29 Jan-31 Jan 100/105/105 90 Day Mean 28 Jan 126 V. Geomagnetic A Indices Observed Afr/Ap 27 Jan 013/016 Estimated Afr/Ap 28 Jan 015/019 Predicted Afr/Ap 29 Jan-31 Jan 010/015-010/015-010/020 VI. Geomagnetic Activity Probabilities 29 Jan-31 Jan A. Middle Latitudes Active 25/25/25 Minor storm 15/15/15 Major-severe storm 05/05/05 B. High Latitudes Active 30/30/30 Minor storm 20/20/20 Major-severe storm 05/05/05