:Product: 0930RSGA.txt :Issued: 2021 Sep 30 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 273 Issued at 2200Z on 30 Sep 2021 IA. Analysis of Solar Active Regions and Activity from 29/2100Z to 30/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C2 event observed at 29/2156Z from Region 2877 (S16W40). There are currently 2 numbered sunspot regions on the disk. IB. Solar Activity Forecast: Solar activity is expected to be very low with a chance for a C-class flares and a slight chance for an M-class flare on days one, two, and three (01 Oct, 02 Oct, 03 Oct). IIA. Geophysical Activity Summary 29/2100Z to 30/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 504 km/s at 30/2050Z. Total IMF reached 14 nT at 30/1818Z. The maximum southward component of Bz reached -9 nT at 30/1811Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 616 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to minor storm levels on day one (01 Oct), quiet to active levels on day two (02 Oct) and quiet to unsettled levels on day three (03 Oct). III. Event probabilities 01 Oct-03 Oct Class M 10/10/10 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 30 Sep 095 Predicted 01 Oct-03 Oct 095/095/095 90 Day Mean 30 Sep 082 V. Geomagnetic A Indices Observed Afr/Ap 29 Sep 004/004 Estimated Afr/Ap 30 Sep 009/011 Predicted Afr/Ap 01 Oct-03 Oct 018/024-008/010-008/008 VI. Geomagnetic Activity Probabilities 01 Oct-03 Oct A. Middle Latitudes Active 45/40/25 Minor Storm 30/20/05 Major-severe storm 05/05/01 B. High Latitudes Active 05/10/15 Minor Storm 20/30/25 Major-severe storm 70/60/30