:Product: 0912RSGA.txt :Issued: 2024 Sep 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 256 Issued at 2200Z on 12 Sep 2024 IA. Analysis of Solar Active Regions and Activity from 11/2100Z to 12/2100Z: 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 12/0943Z. There are currently 9 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 (13 Sep, 14 Sep, 15 Sep). IIA. Geophysical Activity Summary 11/2100Z to 12/2100Z: The geomagnetic field has been at quiet to severe storm levels for the past 24 hours. Solar wind speed reached a peak of 623 km/s at 12/1714Z. Total IMF reached 29 nT at 12/1305Z. The maximum southward component of Bz reached -26 nT at 12/1306Z. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to major storm levels on day one (13 Sep), unsettled to minor storm levels on day two (14 Sep) and quiet to active levels on day three (15 Sep). Protons have a slight chance of crossing threshold on days one, two, and three (13 Sep, 14 Sep, 15 Sep). III. Event probabilities 13 Sep-15 Sep Class M 60/60/60 Class X 15/15/15 Proton 15/15/15 PCAF green IV. Penticton 10.7 cm Flux Observed 12 Sep 201 Predicted 13 Sep-15 Sep 210/210/205 90 Day Mean 12 Sep 217 V. Geomagnetic A Indices Observed Afr/Ap 11 Sep 008/007 Estimated Afr/Ap 12 Sep 040/070 Predicted Afr/Ap 13 Sep-15 Sep 023/035-017/025-015/015 VI. Geomagnetic Activity Probabilities 13 Sep-15 Sep A. Middle Latitudes Active 30/35/30 Minor Storm 35/25/10 Major-severe storm 20/05/01 B. High Latitudes Active 05/10/15 Minor Storm 20/20/30 Major-severe storm 75/60/45