:Product: 0727RSGA.txt :Issued: 2011 Jul 27 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 208 Issued at 2200Z on 27 Jul 2011 IA. Analysis of Solar Active Regions and Activity from 26/2100Z to 27/2100Z: Solar activity was moderate. Region 1260 (N18E30) produced a M1/1n flare at 1607Z as well as numerous C-class flares during the past 24 hours. This region showed some magnetic complexity (magnetic class beta-gamma) and changed steadily throughout the day. Region 1261 (N15E60) is the largest group on the disk (250 millionths) but is a simple magnetic beta group and only produced one subflare during the day. New Region 1262 (N16W38) was assigned and is a small D-type group with a weak delta configuration in the trailing portion of the group. Despite its magnetic complexity 1262 did not produce any flares. The eruption of a filament from the northeast quadrant was observed at about 0620Z and was associated with a faint, slow coronal mass ejection off the northeast limb as observed by the LASCO C2 coronagraph beginning at 0642Z. IB. Solar Activity Forecast: Solar activity is expected to be predominantly low but there is a chance for additional isolated M-class flares from Region 1260. IIA. Geophysical Activity Summary 26/2100Z to 27/2100Z: The geomagnetic field was quiet. The greater than 2 MeV electron flux at geosynchronous orbit reached high levels during the period. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet for the next three days (28-30 July). Recent analysis from Stereo-B and solar imagery suggest that the previously anticipated high speed stream from a coronal hole is most likely to start affecting Earth on 31 July. III. Event Probabilities 28 Jul-30 Jul Class M 40/40/40 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 27 Jul 099 Predicted 28 Jul-30 Jul 100/100/105 90 Day Mean 27 Jul 095 V. Geomagnetic A Indices Observed Afr/Ap 26 Jul 005/005 Estimated Afr/Ap 27 Jul 005/005 Predicted Afr/Ap 28 Jul-30 Jul 005/005-005/005-005/005 VI. Geomagnetic Activity Probabilities 28 Jul-30 Jul A. Middle Latitudes Active 05/05/05 Minor storm 01/01/01 Major-severe storm 01/01/01 B. High Latitudes Active 05/05/05 Minor storm 01/01/01 Major-severe storm 01/01/01