:Product: 0817RSGA.txt :Issued: 2025 Aug 17 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 229 Issued at 2200Z on 17 Aug 2025 IA. Analysis of Solar Active Regions and Activity from 16/2100Z to 17/2100Z: Solar activity has been at low levels for the past 24 hours. There are currently 4 numbered sunspot regions on the disk. IB. Solar Activity Forecast: Solar activity is expected to be low with a slight chance for an M-class flare on days one, two, and three (18 Aug, 19 Aug, 20 Aug). IIA. Geophysical Activity Summary 16/2100Z to 17/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 505 km/s at 17/0549Z. Total IMF reached 6 nT at 17/2026Z. The maximum southward component of Bz reached -4 nT at 17/1137Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 8022 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on day one (18 Aug), unsettled to minor storm levels on day two (19 Aug) and unsettled to active levels on day three (20 Aug). III. Event probabilities 18 Aug-20 Aug Class M 15/15/15 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 17 Aug 117 Predicted 18 Aug-20 Aug 115/110/110 90 Day Mean 17 Aug 136 V. Geomagnetic A Indices Observed Afr/Ap 16 Aug 006/005 Estimated Afr/Ap 17 Aug 005/006 Predicted Afr/Ap 18 Aug-20 Aug 009/012-020/030-014/018 VI. Geomagnetic Activity Probabilities 18 Aug-20 Aug A. Middle Latitudes Active 35/45/35 Minor Storm 20/30/15 Major-severe storm 01/05/01 B. High Latitudes Active 10/05/10 Minor Storm 25/20/30 Major-severe storm 50/70/50