Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 17 August 2017
Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 229 Issued at 2200Z on 17 Aug 2017
IA. Analysis of Solar Active Regions and Activity from 16/2100Z to 17/2100Z: 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 and a slight chance for an M-class flare on days one and two (18 Aug, 19 Aug) and expected to be very low with a chance for a C-class flares on day three (20 Aug).
IIA. Geophysical Activity Summary 16/2100Z to 17/2100Z: The geomagnetic field has been at quiet to minor storm levels for the past 24 hours. Solar wind speed reached a peak of 594 km/s at 17/1851Z. Total IMF reached 13 nT at 17/0733Z. The maximum southward component of Bz reached -12 nT at 17/0820Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 330 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at unsettled to minor storm levels on day one (18 Aug), quiet to active levels on day two (19 Aug) and unsettled to active levels on day three (20 Aug).
III. Event probabilities 18 Aug-20 Aug
Class M 10/10/05
Class X 01/01/01
Proton 01/01/01
PCAF green
IV. Penticton 10.7 cm Flux
Observed 17 Aug 077
Predicted 18 Aug-20 Aug 078/077/076
90 Day Mean 17 Aug 076
V. Geomagnetic A Indices
Observed Afr/Ap 16 Aug 005/006
Estimated Afr/Ap 17 Aug 023/033
Predicted Afr/Ap 18 Aug-20 Aug 019/024-015/018-012/016
VI. Geomagnetic Activity Probabilities 18 Aug-20 Aug
A. Middle Latitudes
Active 35/30/30
Minor Storm 25/15/15
Major-severe storm 05/01/01
B. High Latitudes
Active 10/10/10
Minor Storm 20/25/25
Major-severe storm 65/50/50