Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 24 August 2017

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 236 Issued at 2200Z on 24 Aug 2017

IA.  Analysis of Solar Active Regions and Activity from 23/2100Z to 24/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C3 event observed at 24/0037Z from Region 2671 (N11W56). 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 days one, two, and three (25 Aug, 26 Aug, 27 Aug).

IIA.  Geophysical Activity Summary 23/2100Z to 24/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 469 km/s at 23/2153Z. Total IMF reached 5 nT at 24/1018Z. The maximum southward component of Bz reached -5 nT at 24/1008Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 3701 pfu.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on day one (25 Aug) and quiet levels on days two and three (26 Aug, 27 Aug).

III.  Event probabilities 25 Aug-27 Aug
Class M    15/15/15
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           24 Aug 079
Predicted   25 Aug-27 Aug 079/080/078
90 Day Mean        24 Aug 076

V.  Geomagnetic A Indices
Observed Afr/Ap 23 Aug  017/029
Estimated Afr/Ap 24 Aug  012/013
Predicted Afr/Ap 25 Aug-27 Aug  007/008-005/005-006/005

VI.  Geomagnetic Activity Probabilities 25 Aug-27 Aug
A.  Middle Latitudes
Active                15/10/10
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    15/15/15