:Product: 1216RSGA.txt :Issued: 2024 Dec 16 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 351 Issued at 2200Z on 16 Dec 2024 IA. Analysis of Solar Active Regions and Activity from 15/2100Z to 16/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C4 event observed at 16/0732Z. 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 (17 Dec, 18 Dec, 19 Dec). IIA. Geophysical Activity Summary 15/2100Z to 16/2100Z: The geomagnetic field has been at quiet to active levels for the past 24 hours. Solar wind speed reached a peak of 470 km/s at 15/2304Z. Total IMF reached 12 nT at 16/0002Z. The maximum southward component of Bz reached -7 nT at 16/0721Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 103 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on day one (17 Dec), quiet to unsettled levels on day two (18 Dec) and quiet levels on day three (19 Dec). III. Event probabilities 17 Dec-19 Dec Class M 40/30/30 Class X 05/05/05 Proton 05/05/05 PCAF green IV. Penticton 10.7 cm Flux Observed 16 Dec 167 Predicted 17 Dec-19 Dec 170/170/175 90 Day Mean 16 Dec 200 V. Geomagnetic A Indices Observed Afr/Ap 15 Dec 009/010 Estimated Afr/Ap 16 Dec 011/012 Predicted Afr/Ap 17 Dec-19 Dec 012/015-007/010-005/005 VI. Geomagnetic Activity Probabilities 17 Dec-19 Dec A. Middle Latitudes Active 35/20/10 Minor Storm 15/05/05 Major-severe storm 01/01/01 B. High Latitudes Active 10/15/15 Minor Storm 25/30/20 Major-severe storm 50/30/15