:Product: 20040121RSGA.txt :Issued: 2004 Jan 21 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 021 Issued at 2200Z on 21 Jan 2004 IA. Analysis of Solar Active Regions and Activity from 20/2100Z to 21/2100Z: Solar activity decreased to low levels today. Flare activity was sparse, although Region 543 (S16W21) produced a C2/Sf that occurred at 21/0036Z. A slight decay was seen in this region since yesterday. Region 540 (S14W35) lost the delta structure in the trailing position of spot cluster overnight. Region 542 (N10W16) underwent no significant changes. Region 544 (N08W04) decayed slightly in penumbral coverage during the period. All spotted regions retain their beta-gamma magnetic features. A 28 degree disappearing solar filament was observed on SXI and SOHO/EIT imagery near 21/1200Z. LASCO imagery is inconclusive at this time but initial C2 data indicates there is a resulting CME from this activity. No new regions were numbered today. IB. Solar Activity Forecast: Solar activity is expected to be at low to moderate levels. IIA. Geophysical Activity Summary 20/2100Z to 21/2100Z: The geomagnetic field was at quiet to unsettled levels. The greater than 2 MeV electron flux at geosynchronous orbit reached high levels today. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to range from quiet to minor storm levels. Isolated periods of major storm conditions are possible with the onset of the anticipated shock passage, due early on 22 Jan; resulting from the long duration C-flare that occurred late on 19 Jan. Unsettled to active levels are expected on 23 Jan. Predominantly quiet to unsettled conditions should return by 24 Jan. III. Event Probabilities 22 Jan-24 Jan Class M 25/25/25 Class X 05/05/05 Proton 05/05/05 PCAF green IV. Penticton 10.7 cm Flux Observed 21 Jan 130 Predicted 22 Jan-24 Jan 130/130/125 90 Day Mean 21 Jan 137 V. Geomagnetic A Indices Observed Afr/Ap 20 Jan 011/016 Estimated Afr/Ap 21 Jan 010/015 Predicted Afr/Ap 22 Jan-24 Jan 030/045-015/025-010/015 VI. Geomagnetic Activity Probabilities 22 Jan-24 Jan A. Middle Latitudes Active 45/30/15 Minor storm 25/15/05 Major-severe storm 15/05/01 B. High Latitudes Active 45/35/20 Minor storm 30/20/10 Major-severe storm 15/10/01