:Product: 0104RSGA.txt :Issued: 2025 Jan 04 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 4 Issued at 2200Z on 04 Jan 2025 IA. Analysis of Solar Active Regions and Activity from 03/2100Z to 04/2100Z: Solar activity has been at high levels for the past 24 hours. The largest solar event of the period was a X1 event observed at 04/1248Z from Region 3947 (N09E41). There are currently 13 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 (05 Jan, 06 Jan, 07 Jan). IIA. Geophysical Activity Summary 03/2100Z to 04/2100Z: The geomagnetic field has been at quiet to minor storm levels for the past 24 hours. Solar wind speed reached a peak of 716 km/s at 04/2026Z. Total IMF reached 18 nT at 04/1137Z. The maximum southward component of Bz reached -15 nT at 04/0559Z. Protons greater than 10 MeV at geosynchronous orbit reached a peak level of 2 pfu at 04/2110Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 156 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to minor storm levels on day one (05 Jan), quiet to active levels on day two (06 Jan) and quiet to unsettled levels on day three (07 Jan). Protons have a chance of crossing threshold on days one, two, and three (05 Jan, 06 Jan, 07 Jan). III. Event probabilities 05 Jan-07 Jan Class M 65/65/55 Class X 20/20/10 Proton 25/25/25 PCAF green IV. Penticton 10.7 cm Flux Observed 04 Jan 209 Predicted 05 Jan-07 Jan 200/195/195 90 Day Mean 04 Jan 203 V. Geomagnetic A Indices Observed Afr/Ap 03 Jan 007/006 Estimated Afr/Ap 04 Jan 022/031 Predicted Afr/Ap 05 Jan-07 Jan 018/025-010/012-007/008 VI. Geomagnetic Activity Probabilities 05 Jan-07 Jan A. Middle Latitudes Active 40/35/20 Minor Storm 25/15/05 Major-severe storm 05/01/01 B. High Latitudes Active 10/10/15 Minor Storm 25/25/30 Major-severe storm 60/50/25