Joint USAF/NOAA Report of Solar and Geophysical Activity 24 Oct 2002
Joint USAF/NOAA Report of Solar and Geophysical Activity SDF Number 297 Issued at 2200Z on 24 Oct 2002 IA. Analysis of Solar Active Regions and Activity from 23/2100Z to 24/2100Z: Solar activity was low. Region 162 (N26W04) produced the largest of the few flares occurring today, an impulsive C7/1n at 1810UTC. Modest discrete frequency bursts and a type IV sweep accompanied the flare. The flare site was just west of the large leader spot, far from the seemingly more complicated central portion of this elongated group. The serpentine plage field spans the full extent of the region. Two new regions were assigned, Region 168 (N24W66) and 169 (S19E75). IB. Solar Activity Forecast: Solar activity is expected to be low to moderate. IIA. Geophysical Activity Summary 23/2100Z to 24/2100Z: The geomagnetic field was at unsettled to major storm levels during the past 24 hours. The disturbance was fueled by high speed solar wind (approx. 700 km/s), emanating from a large coronal hole in the western solar hemisphere. The speed began to increase substantially around 0800UTC. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at active to minor storm levels for the next 24 hours, as the high speed solar wind continues to buffet the magnetosphere. Conditions are then expected return to more normal levels during the last 48 hours, as the solar wind calms. III. Event Probabilities 25 Oct-27 Oct Class M 50/50/50 Class X 05/05/05 Proton 05/05/05 PCAF yellow IV. Penticton 10.7 cm Flux Observed 24 Oct 160 Predicted 25 Oct-27 Oct 160/155/155 90 Day Mean 24 Oct 179 V. Geomagnetic A Indices Observed Afr/Ap 23 Oct 006/010 Estimated Afr/Ap 24 Oct 030/040 Predicted Afr/Ap 25 Oct-27 Oct 020/025-015/020-010/015 VI. Geomagnetic Activity Probabilities 25 Oct-27 Oct A. Middle Latitudes Active 50/40/25 Minor storm 20/15/15 Major-severe storm 05/05/05 B. High Latitudes Active 60/50/30 Minor storm 25/20/15 Major-severe storm 05/05/05
