:Product: 20041110RSGA.txt :Issued: 2004 Nov 10 2220 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 315 Issued at 2200Z on 10 Nov 2004 IA. Analysis of Solar Active Regions and Activity from 09/2100Z to 10/2100Z: Solar activity continued at high levels this period. The very active Region 696 (N08W62) produced an X2/3b Tenflare with protons at 10/0213Z. Strong Type II and IV radio sweeps and moderate centimetric radio bursts also accompanied this flare. LASCO imagery showed a very fast asymetrical full halo CME with a plane-of-sky speed estimated at 2000 km/s. Region 696 continues to gradually decrease in area, but maintains a significant delta configuration. The rest of the visible disk was quiet and stable. IB. Solar Activity Forecast: Solar activity is expected to be moderate to high. Region 696, though in decay, maintains potential for major flare activity. This region will rotate around the west limb on 13 November and as a result, solar activity levels are expected to significantly decline. IIA. Geophysical Activity Summary 09/2100Z to 10/2100Z: The geomagnetic field ranged from active to severe storm levels. Yesterday's strong shock at 09/1852Z was followed by a short period of strong southward Bz to near 40 nT, before rotating northward for approximately five hours. At 10/0100Z, the solar wind exceeded 800 km/s and Bz rotated southward again, ranging from -15 to -25 nT for over nine hours. The geomagnetic field response was severe at all latitudes. The period ended at minor storm levels with solar wind speed declining to near 600 km/s. A new influx of high energy protons followed the X2 flare at 10/0213Z. A greater than 10 MeV peak flux of 424 pfu was observed at 10/1655Z. A greater than 100 Mev proton event also occurred in association with the X2 flare. It began on 10/0320Z, peaked at 2.1 pfu at 10/0340Z, and ended at 10/1250Z. The greater that 2 MeV electron flux was at high levels. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to range from unsettled to severe storm levels on 11 and 12 November. The two halo CMEs observed on 09 and 10 November are expected to impact the geomagnetic field on 11 November. Both of these fast CMEs had a strong westward component; however, their combined effects may produce major or even severe storm periods. On 12 November, field conditions are expected to return to mostly unsettled to minor storm levels, with occasional major storm periods at high latitudes. Unsettled to active conditions are expected on 13 November. The greater than 10 MeV proton event currently in progress is expected to end by 12 November. III. Event Probabilities 11 Nov-13 Nov Class M 70/65/60 Class X 20/15/10 Proton 99/25/15 PCAF in progress IV. Penticton 10.7 cm Flux Observed 10 Nov 105 Predicted 11 Nov-13 Nov 100/095/090 90 Day Mean 10 Nov 109 V. Geomagnetic A Indices Observed Afr/Ap 09 Nov 047/120 Estimated Afr/Ap 10 Nov 100/200 Predicted Afr/Ap 11 Nov-13 Nov 075/125-030/050-020/030 VI. Geomagnetic Activity Probabilities 11 Nov-13 Nov A. Middle Latitudes Active 25/40/30 Minor storm 50/25/20 Major-severe storm 25/15/10 B. High Latitudes Active 20/40/40 Minor storm 40/30/20 Major-severe storm 40/20/10