:Product: 0728RSGA.txt :Issued: 2013 Jul 28 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 Solar Geophysical Activity Report and Forecast SDF Number 209 Issued at 2200Z on 28 Jul 2013 IA. Analysis of Solar Active Regions and Activity from 27/2100Z to 28/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C3 event observed at 28/1221Z from Region 1800 (S08W74). There are currently 4 numbered sunspot regions on the disk. IB. Solar Activity Forecast: Solar activity is likely to be low with a slight chance for an M-class flare on day one (29 Jul) and expected to be very low with a chance for a C-class flares and a slight chance for an M-class flare on days two and three (30 Jul, 31 Jul). IIA. Geophysical Activity Summary 27/2100Z to 28/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed, as measured by the ACE spacecraft, reached a peak speed of 521 km/s at 28/1328Z. Total IMF reached 6 nT at 28/0621Z. The maximum southward component of Bz reached -5 nT at 27/2116Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 365 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on days one, two, and three (29 Jul, 30 Jul, 31 Jul). III. Event probabilities 29 Jul-31 Jul Class M 10/10/10 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 28 Jul 109 Predicted 29 Jul-31 Jul 110/120/120 90 Day Mean 28 Jul 120 V. Geomagnetic A Indices Observed Afr/Ap 27 Jul 010/010 Estimated Afr/Ap 28 Jul 007/007 Predicted Afr/Ap 29 Jul-31 Jul 005/005-004/005-004/005 VI. Geomagnetic Activity Probabilities 29 Jul-31 Jul A. Middle Latitudes Active 10/10/10 Minor Storm 01/01/01 Major-severe storm 01/01/01 B. High Latitudes Active 15/15/15 Minor Storm 20/20/20 Major-severe storm 10/10/10