:Product: 0426RSGA.txt :Issued: 2021 Apr 26 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 116 Issued at 2200Z on 26 Apr 2021 IA. Analysis of Solar Active Regions and Activity from 25/2100Z to 26/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C1 event observed at 26/0230Z from Region 2816 (S22W79). There are currently 3 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 days one and two (27 Apr, 28 Apr) and expected to be very low with a chance for a C-class flares on day three (29 Apr). IIA. Geophysical Activity Summary 25/2100Z to 26/2100Z: The geomagnetic field has been at quiet to minor storm levels for the past 24 hours. Solar wind speed reached a peak of 525 km/s at 26/1829Z. Total IMF reached 7 nT at 26/0324Z. The maximum southward component of Bz reached -7 nT at 26/0219Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 351 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on day one (27 Apr) and quiet levels on days two and three (28 Apr, 29 Apr). III. Event probabilities 27 Apr-29 Apr Class M 10/10/05 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 26 Apr 080 Predicted 27 Apr-29 Apr 080/078/078 90 Day Mean 26 Apr 076 V. Geomagnetic A Indices Observed Afr/Ap 25 Apr 016/019 Estimated Afr/Ap 26 Apr 014/016 Predicted Afr/Ap 27 Apr-29 Apr 007/008-006/005-005/005 VI. Geomagnetic Activity Probabilities 27 Apr-29 Apr A. Middle Latitudes Active 15/10/10 Minor Storm 01/01/01 Major-severe storm 01/01/01 B. High Latitudes Active 15/15/15 Minor Storm 25/20/20 Major-severe storm 20/10/10