:Product: 1118RSGA.txt :Issued: 2011 Nov 18 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 322 Issued at 2200Z on 18 Nov 2011 IA. Analysis of Solar Active Regions and Activity from 17/2100Z to 18/2100Z: Solar activity was low. Region 1354 (S15E56) showed gradual intermediate spot growth and produced a C2/Sf flare at 18/1723Z, as well as occasional optical subflares. Region 1346 (S17W17) showed minor spot growth during the period and produced a C1/Sf flare at 18/1643Z. New Region 1355 (N14E73) rotated into view and produced a single optical subflare. Multiple CMEs were evident in SOHO/LASCO and STEREO images, but none were deemed to be Earth-directed. IB. Solar Activity Forecast: Solar activity is expected to be low through the period (19 - 21 November) with a chance for an M-class flare. IIA. Geophysical Activity Summary 17/2100Z to 18/2100Z: The geomagnetic field was quiet. IIB. Geophysical Activity Forecast: Geomagnetic field activity is expected to be at quiet to unsettled levels on day 1 (19 November) due to a possible glancing blow from a CME observed on 14 November. Activity is expected to decrease to quiet levels for the remainder of the period (20 - 21 November). III. Event Probabilities 19 Nov-21 Nov Class M 30/30/30 Class X 01/01/01 Proton 01/01/01 PCAF Green IV. Penticton 10.7 cm Flux Observed 18 Nov 144 Predicted 19 Nov-21 Nov 145/145/145 90 Day Mean 18 Nov 137 V. Geomagnetic A Indices Observed Afr/Ap 17 Nov 002/003 Estimated Afr/Ap 18 Nov 002/005 Predicted Afr/Ap 19 Nov-21 Nov 007/008-005/005-005/005 VI. Geomagnetic Activity Probabilities 19 Nov-21 Nov A. Middle Latitudes Active 15/10/10 Minor storm 05/01/01 Major-severe storm 01/01/01 B. High Latitudes Active 20/10/10 Minor storm 10/01/01 Major-severe storm 01/01/01