:Product: 0428RSGA.txt :Issued: 2026 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 2026 IA. Analysis of Solar Active Regions and Activity from 27/2100Z to 28/2100Z: Solar activity has been at moderate levels for the past 24 hours. There are currently 7 numbered sunspot regions on the disk. IB. Solar Activity Forecast: Solar activity is likely to be moderate with a slight chance for an X-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 452 km/s at 27/2128Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 388 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on days one and two (29 Apr, 30 Apr) and quiet to unsettled levels on day three (01 May). Protons have a slight chance of crossing threshold on days one, two, and three (29 Apr, 30 Apr, 01 May). III. Event probabilities 29 Apr-01 May Class M 70/70/70 Class X 20/20/20 Proton 15/15/15 PCAF green IV. Penticton 10.7 cm Flux Observed 28 Apr 149 Predicted 29 Apr-01 May 148/148/145 90 Day Mean 28 Apr 129 V. Geomagnetic A Indices Observed Afr/Ap 27 Apr 006/007 Estimated Afr/Ap 28 Apr 004/004 Predicted Afr/Ap 29 Apr-01 May 009/012-014/014-010/010 VI. Geomagnetic Activity Probabilities 29 Apr-01 May A. Middle Latitudes Active 25/30/15 Minor Storm 10/15/05 Major-severe storm 01/01/01 B. High Latitudes Active 20/15/15 Minor Storm 30/20/20 Major-severe storm 35/25/20