:Product: 0914RSGA.txt :Issued: 2017 Sep 14 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 257 Issued at 2200Z on 14 Sep 2017 IA. Analysis of Solar Active Regions and Activity from 13/2100Z to 14/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 1 numbered sunspot regions on the disk. IB. Solar Activity Forecast: Solar activity is expected to be very low with a slight chance for a C-class flare on day one (15 Sep) and expected to be very low on days two and three (16 Sep, 17 Sep). IIA. Geophysical Activity Summary 13/2100Z to 14/2100Z: The geomagnetic field has been at quiet to major storm levels for the past 24 hours. Solar wind speed reached a peak of 677 km/s at 14/1915Z. Total IMF reached 22 nT at 14/1425Z. The maximum southward component of Bz reached -19 nT at 14/1418Z. Protons greater than 10 MeV at geosynchronous orbit reached a peak level of 77 pfu at 14/0120Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 957 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at unsettled to major storm levels on day one (15 Sep), unsettled to active levels on day two (16 Sep) and quiet to active levels on day three (17 Sep). Protons greater than 10 Mev have a chance of crossing threshold on day one (15 Sep) and have a slight chance of crossing threshold on day two (16 Sep). III. Event probabilities 15 Sep-17 Sep Class M 01/01/01 Class X 01/01/01 Proton 35/10/01 PCAF green IV. Penticton 10.7 cm Flux Observed 14 Sep 074 Predicted 15 Sep-17 Sep 074/074/074 90 Day Mean 14 Sep 081 V. Geomagnetic A Indices Observed Afr/Ap 13 Sep 013/015 Estimated Afr/Ap 14 Sep 016/027 Predicted Afr/Ap 15 Sep-17 Sep 022/026-018/020-012/012 VI. Geomagnetic Activity Probabilities 15 Sep-17 Sep A. Middle Latitudes Active 30/30/30 Minor Storm 40/15/10 Major-severe storm 10/01/01 B. High Latitudes Active 05/10/15 Minor Storm 20/25/25 Major-severe storm 70/50/40