Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 4 September 2017
Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 247 Issued at 2200Z on 04 Sep 2017
IA. Analysis of Solar Active Regions and Activity from 03/2100Z to 04/2100Z: Solar activity has been at high levels for the past 24 hours. The largest solar event of the period was a M5 event observed at 04/2033Z. 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 (05 Sep, 06 Sep, 07 Sep).
IIA. Geophysical Activity Summary 03/2100Z to 04/2100Z: The geomagnetic field has been at quiet to active levels for the past 24 hours. Solar wind speed reached a peak of 524 km/s at 04/2007Z. Total IMF reached 9 nT at 04/2019Z. The maximum southward component of Bz reached -6 nT at 04/1649Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 15826 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on day one (05 Sep) and quiet levels on days two and three (06 Sep, 07 Sep). Protons have a slight chance of crossing threshold on days one, two, and three (05 Sep, 06 Sep, 07 Sep).
III. Event probabilities 05 Sep-07 Sep
Class M 71/71/71
Class X 25/25/25
Proton 10/10/10
PCAF green
IV. Penticton 10.7 cm Flux
Observed 04 Sep 183
Predicted 05 Sep-07 Sep 140/140/130
90 Day Mean 04 Sep 079
V. Geomagnetic A Indices
Observed Afr/Ap 03 Sep 010/008
Estimated Afr/Ap 04 Sep 010/013
Predicted Afr/Ap 05 Sep-07 Sep 009/010-005/005-005/005
VI. Geomagnetic Activity Probabilities 05 Sep-07 Sep
A. Middle Latitudes
Active 20/15/15
Minor Storm 05/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 20/15/15
Major-severe storm 20/05/10