:Product: 20001026RSGA.txt :Issued: 2000 Oct 26 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 300 Issued at 2200Z on 26 Oct 2000 IA. Analysis of Solar Active Regions and Activity from 25/2100Z to 26/2100Z: Solar activity remained low. Region 9209 (S24E59) produced a C8/1n flare at 1611 UTC, the largest event of the period. It also had other, smaller C-class flares. The other area of activity was the northwest limb, where a C6/sf erupted from a swath of spotless plage near N17W77. That flare occurred at 1137 UTC. One new region, 9210 (S30E74) rotated into view. IB. Solar Activity Forecast: Solar activity is expected to be low to moderate. Region 9209 may produce an isolated M-class event during the next three days. IIA. Geophysical Activity Summary 25/2100Z to 26/2100Z: The geomagnetic field was quiet to unsettled. A proton event at greater than 10 MeV began at 0040 UTC, reached a maximum of 15 pfu at 0340 UTC, and ended at 1000 UTC. This activity is related to the CME off the west limb near midday on the 25th. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to persist at quiet to unsettled for the next 36-48 hours. A mild disturbance from yesterday's halo CME is anticipated to begin late on the 28th. Active conditions are possible through the end of the period as the magnetosphere takes an oblique hit from the solar ejection. III. Event Probabilities 27 Oct-29 Oct Class M 40/40/40 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 26 Oct 171 Predicted 27 Oct-29 Oct 175/175/180 90 Day Mean 26 Oct 169 V. Geomagnetic A Indices Observed Afr/Ap 25 Oct 009/008 Estimated Afr/Ap 26 Oct 010/010 Predicted Afr/Ap 27 Oct-29 Oct 010/010-015/015-015/015 VI. Geomagnetic Activity Probabilities 27 Oct-29 Oct A. Middle Latitudes Active 20/30/30 Minor storm 05/10/10 Major-severe storm 01/05/05 B. High Latitudes Active 25/40/40 Minor storm 05/15/15 Major-severe storm 01/05/05