Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 7 September 2017
Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 250 Issued at 2200Z on 07 Sep 2017
IA. Analysis of Solar Active Regions and Activity from 06/2100Z to 07/2100Z: Solar activity has been at high levels for the past 24 hours. The largest solar event of the period was a X1 event observed at 07/1436Z from Region 2673 (S09W58). There are currently 5 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 (08 Sep, 09 Sep, 10 Sep).
IIA. Geophysical Activity Summary 06/2100Z to 07/2100Z: The geomagnetic field has been at quiet to active levels for the past 24 hours. Solar wind speed reached a peak of 666 km/s at 07/1156Z. Total IMF reached 16 nT at 07/0015Z. The maximum southward component of Bz reached -10 nT at 07/0600Z. Protons greater than 10 MeV at geosynchronous orbit reached a peak level of 352 pfu at 07/0410Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 5443 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at active to severe storm levels on days one and two (08 Sep, 09 Sep) and active to minor storm levels on day three (10 Sep). Protons are expected to cross threshold on days one and two (08 Sep, 09 Sep) and are expected to cross threshold on day three (10 Sep).
III. Event probabilities 08 Sep-10 Sep
Class M 75/75/75
Class X 50/50/50
Proton 99/99/95
PCAF red
IV. Penticton 10.7 cm Flux
Observed 07 Sep 129
Predicted 08 Sep-10 Sep 125/125/120
90 Day Mean 07 Sep 080
V. Geomagnetic A Indices
Observed Afr/Ap 06 Sep 018/010
Estimated Afr/Ap 07 Sep 021/032
Predicted Afr/Ap 08 Sep-10 Sep 035/065-031/050-021/030
VI. Geomagnetic Activity Probabilities 08 Sep-10 Sep
A. Middle Latitudes
Active 15/15/40
Minor Storm 35/35/20
Major-severe storm 50/50/05
B. High Latitudes
Active 10/10/15
Minor Storm 20/25/25
Major-severe storm 55/60/45
