Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 28 September 2016

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 272 Issued at 2200Z on 28 Sep 2016

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 1 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 day one (29 Sep) and expected to be very low with a slight chance for a C-class flare on days two and three (30 Sep, 01 Oct).

IIA. Geophysical Activity Summary 27/2100Z to 28/2100Z: The geomagnetic field has been at unsettled to major storm levels for the past 24 hours. Solar wind speed reached a peak of 798 km/s at 28/1852Z. Total IMF reached 8 nT at 27/2342Z. The maximum southward component of Bz reached -6 nT at 28/1430Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 23935 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at active to major storm levels on day one (29 Sep), unsettled to major storm levels on day two (30 Sep) and unsettled to minor storm levels on day three (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 084
Predicted 29 Sep-01 Oct 085/083/078
90 Day Mean 28 Sep 086

V. Geomagnetic A Indices
Observed Afr/Ap 27 Sep 021/032
Estimated Afr/Ap 28 Sep 028/045
Predicted Afr/Ap 29 Sep-01 Oct 029/044-024/038-024/030

VI. Geomagnetic Activity Probabilities 29 Sep-01 Oct
A. Middle Latitudes
Active 40/40/35
Minor Storm 20/20/15
Major-severe storm 10/10/05
B. High Latitudes
Active 20/20/15
Minor Storm 25/25/20
Major-severe storm 35/35/30