Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 26 August 2017

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 238 Issued at 2200Z on 26 Aug 2017

IA.  Analysis of Solar Active Regions and Activity from 25/2100Z to 26/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 2 numbered sunspot regions on the disk.

IB.  Solar Activity Forecast: Solar activity is likely to be low with a slight chance for an M-class flare on day one (27 Aug) and expected to be very low with a chance for a C-class flares and a slight chance for an M-class flare on days two and three (28 Aug, 29 Aug).

IIA.  Geophysical Activity Summary 25/2100Z to 26/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 432 km/s at 26/2058Z. Total IMF reached 6 nT at 26/2052Z. The maximum southward component of Bz reached -3 nT at 26/1621Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 10279 pfu.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on day one (27 Aug) and quiet to unsettled levels on days two and three (28 Aug, 29 Aug).

III.  Event probabilities 27 Aug-29 Aug
Class M    15/10/10
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           26 Aug 078
Predicted   27 Aug-29 Aug 075/075/075
90 Day Mean        26 Aug 076

V.  Geomagnetic A Indices
Observed Afr/Ap 25 Aug  007/004
Estimated Afr/Ap 26 Aug  005/005
Predicted Afr/Ap 27 Aug-29 Aug  005/005-007/008-007/008

VI.  Geomagnetic Activity Probabilities 27 Aug-29 Aug
A.  Middle Latitudes
Active                10/10/10
Minor Storm           01/01/05
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           15/15/15
Major-severe storm    15/15/15