Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 25 September 2016

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 269 Issued at 2200Z on 25 Sep 2016

IA. Analysis of Solar Active Regions and Activity from 24/2100Z to 25/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C1 event observed at 25/1914Z from Region 2597 (S13W25). 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 days one, two, and three (26 Sep, 27 Sep, 28 Sep).

IIA. Geophysical Activity Summary 24/2100Z to 25/2100Z: The geomagnetic field has been at quiet to minor storm levels for the past 24 hours. Solar wind speed reached a peak of 425 km/s at 25/1755Z. Total IMF reached 11 nT at 25/0908Z. The maximum southward component of Bz reached -10 nT at 25/1021Z.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at unsettled to minor storm levels on day one (26 Sep), quiet to active levels on day two (27 Sep) and unsettled to major storm levels on day three (28 Sep).

III. Event probabilities 26 Sep-28 Sep
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 25 Sep 085
Predicted 26 Sep-28 Sep 085/085/085
90 Day Mean 25 Sep 086

V. Geomagnetic A Indices
Observed Afr/Ap 24 Sep 004/004
Estimated Afr/Ap 25 Sep 016/021
Predicted Afr/Ap 26 Sep-28 Sep 014/018-012/012-024/035

VI. Geomagnetic Activity Probabilities 26 Sep-28 Sep
A. Middle Latitudes
Active 25/20/25
Minor Storm 05/05/20
Major-severe storm 01/01/15
B. High Latitudes
Active 15/15/10
Minor Storm 20/20/20
Major-severe storm 20/25/50