:Product: 20030123RSGA.txt :Issued: 2003 Jan 23 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 023 Issued at 2200Z on 23 Jan 2003 IA. Analysis of Solar Active Regions and Activity from 22/2100Z to 23/2100Z: Solar activity was at moderate levels. The largest event was an M2.5/1n flare at 23/1243 UTC from Region 266 (S22E13). Associated with this event was a Type II radio sweep measuring 578 km/s. A second M-class flare, an M1.0, from Region 266 occurred at 23/0448 UTC with an associated Type II radio sweep (476 km/s). In the last 24 hours, Region 266 has shown increased growth and complexity in the leader spots. The spot group is now 140 millionths in size with a beta-gamma magnetic configuration. Region 263 (S11W68) has also exhibited growth in area coverage. IB. Solar Activity Forecast: Solar activity is expected to be at low to moderate levels. Region 263, 266 and 267 have the potential to produce and isolated M-class event. IIA. Geophysical Activity Summary 22/2100Z to 23/2100Z: The geomagnetic field was at quiet to minor storm levels. The onset of coronal hole effects resulted in minor storm conditions early in the period. NASA/ACE instruments indicate an increase in solar wind speed with peak values near 700 km/s. The Bz component of the interplanetary magnetic field was slightly southward early in the period but has since been, on average, neutral. 2 MeV electron flux at geo-synchronous orbit exceeded event threshold today. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at unsettled to minor storm levels. Continued high speed stream effects have the potential for isolated minor storming on day one of the forecast period. Day two and day three are expected to be quiet to unsettled. III. Event Probabilities 24 Jan-26 Jan Class M 30/30/30 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 23 Jan 136 Predicted 24 Jan-26 Jan 135/130/125 90 Day Mean 23 Jan 160 V. Geomagnetic A Indices Observed Afr/Ap 22 Jan 014/017 Estimated Afr/Ap 23 Jan 017/022 Predicted Afr/Ap 24 Jan-26 Jan 020/020-015/015-015/020 VI. Geomagnetic Activity Probabilities 24 Jan-26 Jan A. Middle Latitudes Active 40/25/20 Minor storm 20/10/05 Major-severe storm 10/01/01 B. High Latitudes Active 50/40/30 Minor storm 30/20/15 Major-severe storm 20/10/05