:Product: 1212RSGA.txt :Issued: 2025 Dec 12 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 346 Issued at 2200Z on 12 Dec 2025 IA. Analysis of Solar Active Regions and Activity from 11/2100Z to 12/2100Z: 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 on day one (13 Dec) and expected to be low with a chance for M-class flares on days two and three (14 Dec, 15 Dec). IIA. Geophysical Activity Summary 11/2100Z to 12/2100Z: The geomagnetic field has been at unsettled to minor storm levels for the past 24 hours. Solar wind speed reached a peak of 509 km/s at 12/0240Z. Total IMF reached 14 nT at 12/2052Z. The maximum southward component of Bz reached -14 nT at 12/2051Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 1078 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to minor storm levels on day one (13 Dec), quiet to active levels on day two (14 Dec) and quiet levels on day three (15 Dec). III. Event probabilities 13 Dec-15 Dec Class M 55/45/35 Class X 05/01/01 Proton 05/05/01 PCAF green IV. Penticton 10.7 cm Flux Observed 12 Dec 135 Predicted 13 Dec-15 Dec 130/120/120 90 Day Mean 12 Dec 151 V. Geomagnetic A Indices Observed Afr/Ap 11 Dec 017/026 Estimated Afr/Ap 12 Dec 020/023 Predicted Afr/Ap 13 Dec-15 Dec 015/019-011/012-007/008 VI. Geomagnetic Activity Probabilities 13 Dec-15 Dec A. Middle Latitudes Active 45/40/40 Minor Storm 25/20/20 Major-severe storm 05/05/05 B. High Latitudes Active 10/10/10 Minor Storm 25/25/25 Major-severe storm 65/60/60