:Product: 20041030RSGA.txt :Issued: 2004 Oct 30 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 304 Issued at 2200Z on 30 Oct 2004 IA. Analysis of Solar Active Regions and Activity from 29/2100Z to 30/2100Z: Solar activity was high. Region 691 (N14W25) grew quickly at the end of yesterday, and emerging flux near the leader spot fueled an instability that resulted in major flares. Chronologically, Region 691 produced: a C9/Sf with type II sweep at 0049UTC, an M3/Sf with type II at 0333UTC, an M4/Sf TENFLARE with types II and IV sweep at 0618UTC, an M3/1n with type II at 0928UTC, an X1/Sf (partially obscured by clouds) TENFLARE with types II and IV sweep at 1146UTC, and most recently an M5/Sn TENFLARE with type II sweep at 1633UTC. Numerous large (i.e., 9500 sfu at 245 MHz at 1413UTC) radio bursts occurred throughout the period. A paucity of LASCO observations made it difficult to discern if associated CMEs occurred, but there seems to be an indication that at least some CME activity did occur in conjunction with the latter flares. The region seems to still retain an amount of potency making additional significant activity likely. Elsewhere, Region 687 (N12W66) and Region 693 (S16E34) each had an occasional small C-class flare as both regions seemed to decay. New Region 695 (S16E68) was numbered. IB. Solar Activity Forecast: Solar activity is expected to be moderate to high. Region 691 is still capable of producing M and X class flares. IIA. Geophysical Activity Summary 29/2100Z to 30/2100Z: The geomagnetic field was quiet to mildly active. Alfven waves in the solar wind coupled with a slow increase in the radial speed caused intervals of active conditions. The greater than 10 MeV proton flux at geosynchronous orbit became enhanced around 0700UTC, in response to earlier activity in Region 691. The flux has hovered near 1 pfu for the past 16 hours. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be generally unsettled for the next 36 hours. Activity is expected to increase near midday on 01 November when effects of shocks and CMEs are due, bringing active to periodic major storming over the final 36 hours of the period. The greater than 10 MeV proton flux may exceed event level if Region 691 produces more M and X level activity. The region is in a well-connected location so this proton increase would be abrupt should it occur. III. Event Probabilities 31 Oct-02 Nov Class M 60/60/60 Class X 30/30/30 Proton 50/50/50 PCAF yellow IV. Penticton 10.7 cm Flux Observed 30 Oct 136 Predicted 31 Oct-02 Nov 135/135/130 90 Day Mean 30 Oct 106 V. Geomagnetic A Indices Observed Afr/Ap 29 Oct 006/007 Estimated Afr/Ap 30 Oct 012/015 Predicted Afr/Ap 31 Oct-02 Nov 010/010-015/025-020/030 VI. Geomagnetic Activity Probabilities 31 Oct-02 Nov A. Middle Latitudes Active 25/35/40 Minor storm 15/20/25 Major-severe storm 05/05/10 B. High Latitudes Active 30/40/45 Minor storm 15/25/35 Major-severe storm 05/05/10