:Product: 1023RSGA.txt :Issued: 2012 Oct 23 2200 UTC # Prepared jointly by the U.S. Dept. of Commerce, NOAA, # Space Weather Prediction Center and the U.S. Air Force. # Joint USAF/NOAA Report of Solar and Geophysical Activity SDF Number 297 Issued at 2200Z on 23 Oct 2012 IA. Analysis of Solar Active Regions and Activity from 22/2100Z to 23/2100Z: Solar activity has been high. Region 1598 (S12E44) produced an X1 event with an associated Tenflare and Type-II radio sweep at 23/0317Z. There was no CME observed in association with this event. Region 1598 remains the most threatening region on the disk and appears to have a Delta magnetic configuration within its trailer spots. Region 1596 (N07E06) is also moderately sized and has some magnetic complexity, but did not produce any flares during the period. Region 1593 (N15W33) produced a long-duration C3 event at 23/0821Z with an associated CME seen on STEREO-A imagery. There is not enough data available to model the CME, but at this time it does not appear likely to be geoeffective. Newly numbered Region 1599 (S09E73) appears to have a simple alpha magnetic class. The other regions on the disk either remained stable or were decaying. IB. Solar Activity Forecast: Solar activity is expected to be moderate to high with occasional M-class events, and a slight chance for an isolated X-class event for the next three days (24 - 26 Oct) with Region 1598 the most likely source. IIA. Geophysical Activity Summary 22/2100Z to 23/2100Z: The geomagnetic field was quiet for the past 24 hours. Solar wind speed, as measured at the ACE spacecraft, remained steady throughout the period at approximately 370 km/s. The Bz component of the interplanetary magnetic field ranged from +/- 4 nT and the Phi angle changed to a positive sector at 22/2300Z. These signatures are consistent with a solar sector boundary crossing. The greater than 2 MeV electron flux at geosynchronous orbit was at high levels throughout the period. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet for the next three days (24 - 26 Oct). III. Event Probabilities 24 Oct-26 Oct Class M 75/75/75 Class X 20/20/20 Proton 05/10/15 PCAF green IV. Penticton 10.7 cm Flux Observed 23 Oct 142 Predicted 24 Oct-26 Oct 140/140/140 90 Day Mean 23 Oct 121 V. Geomagnetic A Indices Observed Afr/Ap 22 Oct 002/002 Estimated Afr/Ap 23 Oct 007/007 Predicted Afr/Ap 24 Oct-26 Oct 006/005-006/005-006/005 VI. Geomagnetic Activity Probabilities 24 Oct-26 Oct A. Middle Latitudes Active 05/05/05 Minor storm 01/01/01 Major-severe storm 01/01/01 B. High Latitudes Active 15/15/15 Minor storm 15/15/10 Major-severe storm 05/05/05