Joint USAF/NOAA Solar Geophysical Activity Report and Forecast SDF Number 271 Issued at 2200Z on 28 Sep 2017
IA. Analysis of Solar Active Regions and Activity from 27/2100Z to 28/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 3 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 on days one, two, and three (29 Sep, 30 Sep, 01 Oct).
IIA. Geophysical Activity Summary 27/2100Z to 28/2100Z: The geomagnetic field has been at active to severe storm levels for the past 24 hours. Solar wind speed reached a peak of 752 km/s at 28/0846Z. Total IMF reached 13 nT at 28/0108Z. The maximum southward component of Bz reached -11 nT at 27/2128Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 3706 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at unsettled to minor storm levels on day one (29 Sep) and quiet to active levels on days two and three (30 Sep, 01 Oct).
III. Event probabilities 29 Sep-01 Oct Class M 01/01/01 Class X 01/01/01 Proton 01/01/01 PCAF green
IV. Penticton 10.7 cm Flux Observed 28 Sep 091 Predicted 29 Sep-01 Oct 091/091/091 90 Day Mean 28 Sep 082
V. Geomagnetic A Indices Observed Afr/Ap 27 Sep 024/037 Estimated Afr/Ap 28 Sep 043/061 Predicted Afr/Ap 29 Sep-01 Oct 021/028-014/018-011/014
VI. Geomagnetic Activity Probabilities 29 Sep-01 Oct A. Middle Latitudes Active 35/30/30 Minor Storm 30/15/15 Major-severe storm 05/01/01 B. High Latitudes Active 10/10/15 Minor Storm 20/30/25 Major-severe storm 60/50/50