:Product: 0811RSGA.txt :Issued: 2023 Aug 11 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 223 Issued at 2200Z on 11 Aug 2023 IA. Analysis of Solar Active Regions and Activity from 10/2100Z to 11/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C8 event observed at 11/0656Z from Region 3395 (N13W31). There are currently 7 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 (12 Aug, 13 Aug, 14 Aug). IIA. Geophysical Activity Summary 10/2100Z to 11/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 541 km/s at 10/2221Z. Total IMF reached 7 nT at 11/1653Z. The maximum southward component of Bz reached -4 nT at 11/1535Z. Protons greater than 10 MeV at geosynchronous orbit reached a peak level of 3 pfu at 10/2110Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 1386 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on days one and two (12 Aug, 13 Aug) and quiet to unsettled levels on day three (14 Aug). Protons greater than 10 Mev have a slight chance of crossing threshold on day one (12 Aug). III. Event probabilities 12 Aug-14 Aug Class M 25/25/25 Class X 05/05/05 Proton 15/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 11 Aug 153 Predicted 12 Aug-14 Aug 150/145/140 90 Day Mean 11 Aug 166 V. Geomagnetic A Indices Observed Afr/Ap 10 Aug 008/008 Estimated Afr/Ap 11 Aug 006/005 Predicted Afr/Ap 12 Aug-14 Aug 006/005-005/005-007/008 VI. Geomagnetic Activity Probabilities 12 Aug-14 Aug A. Middle Latitudes Active 10/10/15 Minor Storm 01/01/01 Major-severe storm 01/01/01 B. High Latitudes Active 15/15/15 Minor Storm 15/15/20 Major-severe storm 10/10/15