:Product: 0428RSGA.txt :Issued: 2017 Apr 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 118 Issued at 2200Z on 28 Apr 2017 IA. Analysis of Solar Active Regions and Activity from 27/2100Z to 28/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 3 numbered sunspot regions on the disk. IB. Solar Activity Forecast: Solar activity is expected to be very low with a slight chance for a C-class flare on days one, two, and three (29 Apr, 30 Apr, 01 May). 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 reached a peak of 493 km/s at 27/2351Z. Total IMF reached 5 nT at 28/1949Z. The maximum southward component of Bz reached -5 nT at 28/2049Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 56297 pfu. NOTE: From 28/1727-1913 UTC, solar wind speed, temperature, and density registered incorrect readings. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on day one (29 Apr), quiet to unsettled levels on day two (30 Apr) and quiet to active levels on day three (01 May). III. Event probabilities 29 Apr-01 May Class M 01/01/01 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 28 Apr 078 Predicted 29 Apr-01 May 078/078/076 90 Day Mean 28 Apr 077 V. Geomagnetic A Indices Observed Afr/Ap 27 Apr 010/008 Estimated Afr/Ap 28 Apr 005/006 Predicted Afr/Ap 29 Apr-01 May 005/005-008/008-011/012 VI. Geomagnetic Activity Probabilities 29 Apr-01 May A. Middle Latitudes Active 05/10/25 Minor Storm 01/05/05 Major-severe storm 01/01/01 B. High Latitudes Active 15/15/15 Minor Storm 15/20/30 Major-severe storm 10/20/30