:Product: 0519RSGA.txt :Issued: 2025 May 19 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 139 Issued at 2200Z on 19 May 2025 IA. Analysis of Solar Active Regions and Activity from 18/2100Z to 19/2100Z: Solar activity has been at moderate levels for the past 24 hours. There are currently 5 numbered sunspot regions on the disk. IB. Solar Activity Forecast: Solar activity is expected to be low with a chance for M-class flares on days one, two, and three (20 May, 21 May, 22 May). IIA. Geophysical Activity Summary 18/2100Z to 19/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 686 km/s at 18/2158Z. Total IMF reached 6 nT at 19/2058Z. The maximum southward component of Bz reached -5 nT at 18/2117Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 1869 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on days one and two (20 May, 21 May) and quiet to unsettled levels on day three (22 May). III. Event probabilities 20 May-22 May Class M 35/35/35 Class X 05/05/05 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 19 May 117 Predicted 20 May-22 May 118/118/120 90 Day Mean 19 May 160 V. Geomagnetic A Indices Observed Afr/Ap 18 May 016/ 022 Estimated Afr/Ap 19 May 009/010 Predicted Afr/Ap 20 May-22 May 011/012-009/012-007/010 VI. Geomagnetic Activity Probabilities 20 May-22 May A. Middle Latitudes Active 30/30/15 Minor Storm 15/15/05 Major-severe storm 01/01/01 B. High Latitudes Active 15/15/15 Minor Storm 30/30/25 Major-severe storm 45/45/25