:Product: 0906RSGA.txt :Issued: 2017 Sep 06 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 249 Issued at 2200Z on 06 Sep 2017 IA. Analysis of Solar Active Regions and Activity from 05/2100Z to 06/2100Z: Solar activity has been at high levels for the past 24 hours. The largest solar event of the period was a X9 event observed at 06/1202Z from Region 2673 (S09W45). There are currently 4 numbered sunspot regions on the disk. IB. Solar Activity Forecast: Solar activity is expected to be moderate with a chance for X-class flares on days one, two, and three (07 Sep, 08 Sep, 09 Sep). IIA. Geophysical Activity Summary 05/2100Z to 06/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 494 km/s at 06/0259Z. Total IMF reached 5 nT at 06/0136Z. The maximum southward component of Bz reached -2 nT at 06/1325Z. Protons greater than 10 MeV at geosynchronous orbit reached a peak level of 155 pfu at 05/2100Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 7224 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at unsettled to severe storm levels on day one (07 Sep) and active to severe storm levels on days two and three (08 Sep, 09 Sep). Protons are expected to cross threshold on day one (07 Sep), have a chance of crossing threshold on day two (08 Sep) and have a slight chance of crossing threshold on day three (09 Sep). III. Event probabilities 07 Sep-09 Sep Class M 75/75/75 Class X 50/50/50 Proton 85/25/15 PCAF red IV. Penticton 10.7 cm Flux Observed 06 Sep 133 Predicted 07 Sep-09 Sep 135/135/135 90 Day Mean 06 Sep 080 V. Geomagnetic A Indices Observed Afr/Ap 05 Sep 011/011 Estimated Afr/Ap 06 Sep 019/037 Predicted Afr/Ap 07 Sep-09 Sep 032/045-035/052-031/045 VI. Geomagnetic Activity Probabilities 07 Sep-09 Sep A. Middle Latitudes Active 15/15/15 Minor Storm 35/35/35 Major-severe storm 50/50/50 B. High Latitudes Active 15/10/10 Minor Storm 35/20/25 Major-severe storm 45/55/60