:Product: 0617RSGA.txt :Issued: 2011 Jun 17 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 168 Issued at 2200Z on 17 Jun 2011 IA. Analysis of Solar Active Regions and Activity from 16/2100Z to 17/2100Z: Solar activity decreased to very low levels. Region 1234 (S16W48) and Region 1236 (N17E33) each produced isolated B-class x-ray flares. A B7 x-ray flare occurred near the SE limb at 17/0646Z. Region 1234 showed a gradual increase in interior spots during the period and was classified as a Dsi group with a simple bipolar magnetic structure. Region 1236 showed a gradual decrease in magnetic complexity in its trailer portion and was classified as a Dho with a beta-gamma magnetic structure. No new regions were numbered. No Earth-directed coronal mass ejections (CME) were observed during the period. IB. Solar Activity Forecast: Solar activity is expected to be low through the period (18 - 20 June) with a chance for an isolated M-class flare. IIA. Geophysical Activity Summary 16/2100Z to 17/2100Z: Geomagnetic activity was at quiet to active levels. An active period was observed during 07/0000 - 0300Z. A geomagnetic sudden impulse (SI) was observed at Boulder at 17/0244Z (31 nT) and indicated the arrival of the partial-halo CME observed on 14 June. IIB. Geophysical Activity Forecast: Geomagnetic activity is expected to be at quiet to unsettled levels on day 1 (18 June). Activity is expected to decrease to quiet levels on day 2 (19 June). An increase to quiet to unsettled levels is expected on day 3 (20 June) as a coronal hole high-speed stream begins to disturb the field. III. Event Probabilities 18 Jun-20 Jun Class M 20/20/20 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 17 Jun 104 Predicted 18 Jun-20 Jun 105/105/105 90 Day Mean 17 Jun 104 V. Geomagnetic A Indices Observed Afr/Ap 16 Jun 003/004 Estimated Afr/Ap 17 Jun 013/013 Predicted Afr/Ap 18 Jun-20 Jun 007/008-005/005-008/008 VI. Geomagnetic Activity Probabilities 18 Jun-20 Jun A. Middle Latitudes Active 15/10/20 Minor storm 01/01/05 Major-severe storm 01/01/01 B. High Latitudes Active 20/15/25 Minor storm 01/01/10 Major-severe storm 01/01/01