:Product: 1023RSGA.txt :Issued: 2010 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 296 Issued at 2200Z on 23 Oct 2010 IA. Analysis of Solar Active Regions and Activity from 22/2100Z to 23/2100Z: Solar activity was very low. Region 1117 (N22E28) grew in area and spots as well as increased in magnetic complexity. It produced a B4 x-ray flare at 23/2011Z. The characteristics of Region 1115 (S29W36) did not change much, though it produced a B3 x-ray flare at 26/1738Z. The leading edge of the CME from a disappearing filament on 21 October was visible on both STEREO A and B HI1 images. IB. Solar Activity Forecast: Solar activity is forecast to be predominately low with a chance for a C-class flare on days 1-3 (24-26 October). IIA. Geophysical Activity Summary 22/2100Z to 23/2100Z: The geomagnetic field was mostly unsettled to active with a period of minor to major storming at high latitudes between 23/1200-1500Z as the result of coronal hole effects. Solar wind speeds were near or above 650 km/s throughout most of the period. IIB. Geophysical Activity Forecast: The geomagnetic field is forecast to be unsettled to active with isolated periods of minor storming likely at all latitudes and a chance for major storming at high latitudes for days 1-2 (24-25 October). Conditions are forecast to be mostly unsettled to active with a chance for an isolated minor storm on day 3 (26 October) at all latitudes. The elevated activity is expected in part to a large, favorably positioned coronal hole as well as a possible glancing blow on 25 October from the aforementioned CME. III. Event Probabilities 24 Oct-26 Oct Class M 01/01/01 Class X 01/01/01 Proton 01/01/01 PCAF Green IV. Penticton 10.7 cm Flux Observed 23 Oct 084 Predicted 24 Oct-26 Oct 084/084/084 90 Day Mean 23 Oct 081 V. Geomagnetic A Indices Observed Afr/Ap 22 Oct 004/006 Estimated Afr/Ap 23 Oct 012/025 Predicted Afr/Ap 24 Oct-26 Oct 015/020-015/018-012/012 VI. Geomagnetic Activity Probabilities 24 Oct-26 Oct A. Middle Latitudes Active 30/30/50 Minor storm 50/50/30 Major-severe storm 20/20/10 B. High Latitudes Active 10/10/40 Minor storm 50/50/40 Major-severe storm 40/40/20